Rad Review Questions

The ejection of an electron from an atom, which produces charged-ion pairs or free radicalsionization

1 second = __ impulses of xrays 60

Amps (mA) describe the ____ of electrons flowing number

Voltage (kPv) describes the ____ of electrons flowing speed

The higher the voltage, the ____ the potential difference higher

Only ____ and ____ affect penetration (quality) kVp and filtration

In aluminum filtration the number of photons ____. decrease

As the beam spreads, the number of photons ____. decrease

More phtons = ____ density. more

Energy = ____. darkness

The more aluminum in the machine, the ____ the film. lighter

A short scale of contrast means mostly ____ (high visual contrast). black and whites

A long scale of contrast means ____ (low visual contrast). many shades of gray

What are the only 2 things contrast can be affected by? aluminum filtration and kVp

A short scale contrast results from ____ kVp and aluminum. less

A long scale contrast results from ____ kVp and aluminum. more

The more kVp or aluminum, the more steps or ____. shades of gray

These produce the sharpest images with the least magnification: ____ focal spot, ____ object-to-film distance, ____ target(sorce)-to-film distance, film and tooth ____, beam ____ to film small, short, large, parallel, perpendicular

Area of unsharpness penumbra

In taking 2 radiographs, if the object moves in the same direction as the tube head, the object is ____ (SLOB). lingual

In taking 2 radiographs, if the object moves in the opposite direction as the tube head, the object is ____ (SLOB). buccal

Inverse square law formula original energy/new energy = (new distance) squared/(original distance) squared

In any distance is doubled or halved, the original energy changes by a factor of __. 4

Anatomically, the sinus floor doesn't turn vertical until the ____.canine

Radiopaque or radiolucent? sinus floor opaque

Zygomatic arch aka ____ malar process

The mental foramen is inferior between what 2 teeth? mandibular premolars

Radiopaque or radiolucent? genial tubercles opaque

Backwards film placement (looks like a grid) aka: herringbone

A film exposed to light is going to be ____. black

An unexposed film is going to be ____. white

What error would be if teeth look like they've been cut in half? double exposure

Panoramic error: anterior teeth look blurred and thin (anorexic) too far anterior

Panoramic error: anterior teeth are blurred and wide (pudgy) too far posterior

Panoramic error: reverse curve of occlusion (frowning) chin too high

Panoramic error: exaggerated curve of occlusion (joker) chin too low

Panoramic error: imposing air space (space between apex of maxillary roots and hard palate) tongue not placed against palate

Panoramic error: imposing spinal shadow patient slumped forward

Silver halide crystals (Bromide crystals) on both sides of film film emulsion

What solution turns only exposed crystals to metallic silver developer

What solution removes undeveloped or unexposed crystals? fixer

What would happen if the fixer is exhausted or not replenished after time, problem is poor wash?discolored film

Film has ____ resolution than digital higher

Most common mechanism of damage in humans (aka free radicals in water) hydrolysis

Rapid turnover rate or mitosis rate of cells ____ damage, undifferentiated cells have ____ damage.increase, increased

Time between xray exposure and maximum damage observed latent period

What tissues have the highest sensitivity to radiation (including the highest) (5)? highest-reproductive

lymph, bone marrow, intestines, mucous membranes

What tissues have the lowest sensitivity to radiation (including the lowest) (5)? lowest-nerves

heart, optic lens, mature bone, mature cartilage

Adverse reactions of the body to radiation never return exactly to original state, therefore build up over lifetime cumulative effect

MPD non-occupational (fetus of auxiliary) 1/10

What 2 units of radiation exposure are on a docimeter report? Rem, Sievert (Sv.)

ALARA as low as reasonably achievable

Each alphabetical film group is two times ____ than the previous film group and needs ____ as much radiation exposure faster, half

Panoramic intensifying screens ____ the amount of radiation. reduce

What device reduces scatter and sizes beam? collimator

Beam size at the patient's face can be no larger than ____ inches. 2.75

What is the advantage of rectangular collimation? reduces the area of patient's skin surface exposed by 60-65%

How much aluminum filtration is needed for up to 70 kVp? 1.5 mm

How much aluminum filtration is needed for more than 70 kVp? 2.5 mm

T or F Walls do not require lead lining. True

The lead apron absorbs __% of scatter that would have reached the reproductive tissues. Lead equivalent to __ mm. 90%, 0.25 mm

In the electromagnetic family, the shorter the group's wavelength, the ____ the energy. stronger

What separates xrays from the rest of the electromagnetic family? xrays produce ionization

Movement of electrons (-) along a wire toward a (+) charge which changes direction 60 times per secondAC electricity

Number of xray photons given off in a period of time quantity of beam

Penetrating power/strength of the xray photonsquality of beam

Discovery of x-rays Roentgen in 1895 while experimenting with Cathode ray tube

Ionization The ejection of an electron from an atom. Produces charged-ion or free radicals.

AC electricity Movement of electrons (-) along a wire toward a (+) charge which changes directions 60 times per second. Many x-ray machines produce 60 bursts or impulses of radiation per second.

Conversion to impulses 1 second= 60 impulses of x-rays

1/4=15 impulses of x-rays

Amperes Amps (mA) describe the number of electrons flowing.

Voltage Volts (kVp) describes the potential differences between the (-) and (+) therefore, the speed or force of the moving electrons towards the (+) charge.

Quantity of the beam The number of x-ray photons given off in a period of time.

Quality of the beam Penetrating nature/power of the x-ray photons (involves wavelengths)

Milliamps (mA) The higher the mA, the higher the electrons= more x-rays. Number of photons increase (Quantity)

Exposure Time Number of photons increase (quantity)

Kilovolt peak (kVp) Number of photons increase. Shorter wavelengths (more penetration). (Quantity and quality)

Aluminum filtration Number of photons decrease. Removes long wavelength dangerous photons. The higher the filtration the lighter the film. Lowers quantity.

Greater than 70 kVp=2.5 mm

Less than or equal to 70 kVp= 1.5 mm

Distance Number of photons decrease as beam spreads. Lowers quantity.

Density More photons= more density (energy=blackness). Affected by mA, exposure time, kVp, decreased filtration, and decreased distance.

Short scale contrast Mostly blacks and whites (high visual contrast). Results from less kVp and aluminum filtration.

Long scale contrast Many shades of gray (low visual contrast). Results from more kVp and aluminum filtration.

Penumbra Area of unsharpness

Principles of shadowcasting These produce the sharpest images with the least magnification:

1. Small focal spot

2. Short object-to-film distance

3. Large target(source)-to-film distance (TFD) or (SFD)

4. Film and tooth parallel

5. Beam perpendicular to film

SLOB rule Same lingual, opposite buccal.

The lingual object moves in the same direction as the tube head.

The buccal object moves in the opposite direction as the tube head.

Inverse square law Original energy = (New distance)2

------------- --------------

new energy (Original distance)2

Film emulsion Silver halide (bromide) crystals on both sides of the film.

Developer (Elon and hydroquinone) turns only exposed crystals to metallic and silver.

Fixer (Sodium thiosulfate) removes undeveloped (including unexposed) crystals

Discolored film Exhausted fixer or poor replenishment, after time, problem is poor wash

Digital Radiography 1) Direct (CCD): chip in camera

Indirect (PSP Photo-stimuable-phosphor): plates run through scanner.

2) Digital requires less radiation than any film available

3) Film has higher resolution than digital

Hydrolysis Free radicals of water. The most common mechanism of damage in humans.

Biological sensitivity to radiation 1) Rapid turnover or mitosis rate of cells increases tissue damage

2) Undifferentiated cells have increase damage

3) Children more sensitive due to rapid mitosis

Latent period Time between x-ray exposure and maximum damage observed

Somatic vs. Genetic effects of radiation Genetic effects are only those that can be passes to future generations

High tissue sensitivity to radiation Reproductive tissue (#1)

Lymphoid tissue

Bone marrow

Intestines

Mucous membranes

Low sensitivity Nerve tissue (#1)

Skeletal muscle

Heart

Optic lens

Mature bone

Mature cartilage

Cumulative effect Adverse reactions of the body to x-radiation never return exactly to original state, therefore, accumulating to some degree over a lifetime.

Gonadal exposure for the average complete mouth series Equal to 3 days to one week of normal background whole radiation.

Exposure in air units Roentgen (old) or Coulomb/Kg (S.I. units)

Absorbed dose units Rad (old) or Gray [Gr.] (S.I. units)

Dose equivalent in man units Rem (old) or Sievert [Sv.] (S.I. units)

Maximum Permissible Dose Occupational 50mSv./year or 5000 mrem/year

4mSv./mo. or 400 mrem/mo.

1mSv./wk. or 100 mrem/wk

Maximum Permissible Dose Non-occupational 5mSv./year or 500 mrem/year

ALARA As low as reasonably achievable

Film speed Most effective method of protection. Each alphabetical film group is 2 times faste than the previous film group and needs half as much radiation exposure.

Intensifying screen Intensify energy with less exposure

Collimation Sizes beam and reduces scatter. Beam size at the patient's face can be no larger than 2.75 inches.

Rectangular collimation Reduces the area of patient's skin surface exposed by 60% to 65% over round.

Lead apron Absorbs 90% of scatter that would have reached the reproductive tissue. Lead equivalent of 0.25 mm

All of the forms of energy comprising the electromagnetic family behave similarly EXCEPT for which characteristic:

a. all cause ionization of tissues

b. all can produce "shadows"

c. all travel in straight lines

d. all travel at the speed of light A. all cause ionization of tissues

How many impulses equal a 1/4 second exposure time?

a. 6 impulses

b. 10 impulses

c. 15 impulses

d. 20 impulses C. 15 impulses

X-rays are generated when a stream of electrons traveling from one side of an x-ray tube is suddenly stopped by its impact on the:

a. filament cup

b. tungsten target of the anode

c. tungsten target of the cathode

d. the aluminum filter B. Tungsten target of the anode

As you go from a "D-speed" to an "E-speed" film, the exposure time should be approximately:

a. doubled

b. halved

c. cut to 1/4 of the original time

d. tripled B. Halved

The mA setting controls which FOUR items below?

a. thermionic emission

b. number of free electrons in the tube

c. number of protons ultimately produced

d. the density of the film

e. contrast of the film A,B,C,D

Thermionic emission

Number of free electrons in the tube

Number of protons ultimately produced

The density of the film

Which of the following reduces the percentage of low energy x-rays in the beam?

a. collimation

b. aluminum filtration

c. milliamperage B. Aluminium filtration

The mean penetrability of an x-ray beam is related to all in the list below EXCEPT:

a. kVp

b. filtration

c. wavelength

d. mA D. mA

If a radiology technician received a dose of 3 Sieverts standing 4 feet from the source of radiation during an exposure, how many Sieverts would he receive during the same exposure standing 2 feet away?

a. 1.5 Sieverts

b. 6 Sieverts

c. 12 Sieverts

d. 27 Sieverts C. 12 Sieverts

A bitewing film is exposed properly using an exposure setting of 1 second with the x-ray source 8 inches away from the patient. What time would be needed if the source was moved 16 inches away?

a. 1/2 second

b. 1/4 second

c. 2 seconds

d. 4 seconds D. 4 seconds

For optimal detection of incipient interproximal carious lesions (high contrast), which of the following machine settings if preferable?

a. 90 kVp, 10 mA

b. 85 kVp, 10 mA

c. 75 kVp, 5 mA

d. 65 kVp, 10 ma D. 65 kVp, 10 mA

Which of the following TWO factors control the QUALITY of the x-ray beam and thus, film contrast?

a. exposure time


c. kVp

d. distance B, C Aluminum filtration and kVp

If a machine operated with good radiographic results at a setting of 15 mA, 90 kVp, and 8 impulses, what exposure time should be used if the machine is changed to 10 mA and 90 kVp?

a. 120 impulses

b. 90 impulses

c. 24 impulses

d. 12 impulses D. 12 impulses

Increasing the kVp results in:

a. a long scale of contrast

b. a short scale of contrast

c. neither, it would have no effect A. A long scale of contrast

Image magnification results from decreased:

a. target size

b. target-film-distance

c. object-film-distance B. Target-film-distance

Occlusal radiographs are taken using which size film?

a. #1

b. #2

c. #3

d. #4 D. #4

Exposure time and mA control:

a. quality of the beam

b. x-ray photon wavelength

c. number of x-ray produced

d. cross section of the beam C. Number of x-rays produced

GBX II filters are needed for extraoral radiographs due to:

a. double emulsion

b. thicker emulsion

c. larger film surface area

d. film is more sensitive to visible light D. Film is more sensitive to visible light

The optimum operating temperature for dental automatic processors is:

a. 65 degrees F

b. 82 degrees F

c. 95 degrees F

d. 100 degrees F B. 82 degrees F

The primary purpose of sodium thiosulfate is to:

a. preserve the image

b. allow further blackening of the film

c. remove the silver bromide crystals that have been developed

d. remove the silver bromide crystals that have not been developed D. Remove the silver bromide crystals that have not been developed

Films not fixed for a long enough period of time will appear:

a. to have black line running through them

b. to be brittle

c. to have a brown tint

d. white C. To have a brown tint

For reducing scatter radiation, the radiation diameter at the patient's face should not exceed:

a. 2.75 inches

b. 3.0 inches

c. 3.5 inches

d. 3.75 inches A. 2.75 inches

The minimum total aluminum filtration on a dental x-ray machine capable of operating at 70 kVp and above is"

a. 2.0 mm Al

b. 2.5 mm Al

c. 2.75 mm Al

d. 3.0 mm Al B. 2.5 mm Al

Match all of these terms to their sensitivity to radiation damage:

a. sperm cells 1. Radio-sensitive

b. spinal tissues 2. Radio-insensitive

c. ovaries

d. mature bone Radio-sensitive: Sperm cells and ovaries

Radio-insensitive: Mature bone and spinal tissues

According to the NCRP, the maximum amount of radiation an occupationally exposed person may receive in one year is:

a. 5 Sv.

b. 1 mSv.

c. 4 mSv.

d. 0.05 Sv. D. 0.05 Sv.

According to the NCRP, the maximum amount of radiation an occupationally exposed person may receive in one week is:

a. 50 rem

b. 5 rem

c. 100 mrem

d. 10 mrem C. 100 mrem

If an operator can stand 6 feet or more away from the source of radiation scatter and out of the primary beam, no barrier wall is necessary.

a. True

b. False A. True

Rand the following PID's in order from least safety to most safety.

a. Long, round

b. Short, round

c. Long, rectangular, lead lined

d. Long, rectangular 1. B. Short, round

2. A. long, round

3. D. Long, rectangular

4. C. Long, rectangular, lead lined

If a person who works with radiation and wears a film badge or dosimeter and has radiographs taken on themselves as a patient, what should be done with the dosimeter during exposure?

a. Wear the badge during exposure to record how much dosage they received.

b. Wear the badge but keep it under the lead apron.

c. Leave the badge outside of the room. C. Leave the badge outside of the room

The U-shaped radiopacity seen in the maxillary posterior is the:

a. zygomatic cross section

b. coronoid process

c. tuberosity

d. condensing osteitis A. Zygomatic cross section

What is the proper thickness of the lead lining in radiographic lead aprons?

a. 0.1 mm equivalent

b. 0.25 mm equivalent

c. 1.0 mm equivalent

d. 2.5 mm equivalent B. 0.25 mm equivalent

Intensifying screens in panoramic cassettes are necessary to:

a. increase sharpness

b. decrease magnification

c. increase film detail

d. reduce patient exposure D. Reduce patient exposure

A film that has turned brown after the span of one year may have resulted from:

a. insufficient wash

b. extremely high developer temperature

c. fixing before developing

d. the radiograph has simply aged and turned with time and is normal A. Insufficient wash

What is the most radiolucent dental material seen on dental radiographs?

a. acrylic

b. gutta percha

c. amalgam

d. aluminum temporary crowns A. Acrylic

What is the earliest clinical sign of an over exposure to x-radiation?

a. loss of hair

b. breakage of chromosome bonds

c. mucosal sloughing

d. erythema D. Erythema

The greatest cause of human radiation effects in dental radiography involves which of the TWO terms below?

a. lysis of proteins

b. destruction of enzymes

c. free radicals of water

d. hydrolysis C Free radicals of water

D Hydrolysis

Cell sensitivity to radiation is most pronounced EXCEPT:

a. during mitosis

b. during periods of increased metabolism

c. during embryonic development

d. in mature bone D. In mature bone

Tissue damage increases with DECREASED:

a. exposure dose

b. body coverage

c. cell differentiation

d. mitotic rate C. Cell differentiation

What is the effect of excessive vertical angulation?

a. foreshortening

b. elongation

c. overlap A. Foreshortening

In the bisecting-the-angle technique, the central ray is directed perpendicular to:

a. the film

b. the long axis of the tooth

c. the imaginary line bisecting the film and tooth

d. the patient's Frankfort plane C. The imaginary line bisecting the film and tooth

A panoramic image with a 'jack-o-latern' or extreme smile results from:

a. chin too low

b. chin too high

c. patient placed too far anteriorly

d. patient places too far posteriorly A. Chin too low

Bisecting-the-angle technique can often lead to:

a. elongation

b. overlap

c. film fog

d. foreshortening D. Foreshortening

All can create film fog EXCEPT:

a. light leaks

b. proper refrigeration

c. chemistry which is too hot

d. faulty safelight B. Proper refrigeration

Select the TWO terms associated with an x-ray 'exposure'.

a. Coulombs/kg

b. Sievarts

c. Rems

d. Roentgens A. Couloumbs/Kg

D. Roentgens

Electrons within the x-ray tubehead emanate from the:

a. anode

b. cathode

c. aluminum filter

d. collimator B. Cathode

On a panoramic radiograph the condyles are projected off of the top of the film. This result occurs when:

a. the patient is positioned too far anteriorly

b. the patient's chin is tipped too high

c. the patient's head is tipped too low

d. the patient is positioned too par posteriorly B. The patient's chin is tipped too high

All of the following are types of electromagnetic radiation EXCEPT one. Which is the exception?

a. X-rays

b. Electrons

c. Radar waves

d. Microwaves A. X-rays

Choose the TWO items that influence the mean energy of an X-ray beam

a. Kilovoltage

b. Milliamperage

c. Amount of filtration

d. Rectangular collimation

e. Quantity of electrons in the tube current A. Kilovoltage

C. Amount of filtration

The filament functions function to:

a. release photons

b. release electrons

c. convert electrons into photons

d. convert photons into electrons

e. None of the above answers is correct B. Release electrons

The term ALARA stands for:

a. optimizing image quality

b. an algorithm for limiting patient exposure

c. reducing the costs of radiographic examination

d. reducing patient exposure to as low as is reasonably achievable

e. a legal requirement to optimize occupational exposure in dental radiology D. Reducing patient exposure to as low as is reasonable achievable

X-ray film is composed of:

a. fluorescent particles that react to x-radiation

b. sodium thiosulfate crystals suspended within a plastic base

c. a plastic base coated with silver halide crystals suspended in gelatin

d. silver halide crystals suspended in plastic and coated on a gelatin baseC. A plastic base coated with silver halide crystals suspended in gelatin

It is generally desirable that x-ray films be all of the following EXCEPT:

a. high speed

b. fine grain size

c. sensitive to visible light

d. coated with emulsion on both sides C. Sensitive to visible light

You are unsure of the location of an opaque mass superimposed over the root of a mandibular premolar. A second view of the same region, made with the tubehead oriented more from the mesial,

reveals that the object mesially with respect to the premolar root as compared to the first radiograph. The object is located:

a. buccal to the premolar root

b. lingual to the premolar root

c. in the same buccal-lingual orientation as the premolar root

d. There is insufficient information to answer the question. B. Lingual to the premolar root

The traditional unit for measuring x-ray exposure in air is termed:

a. rad

b. rem

c. gray

d. roentgen

e. coulombs/kg D. Roentgen

If after development, a radiograph is too light, it may be an indication that:

a. the exposure time was too long

b. the fixer solution needs changing

c. the developer solution was too hot

d. the film was not sufficiently washed

e. the developer solution needs changing E. The developer solution needs changing

If an unwrapped, nonprocessed x-ray film is exposed to normal light for one second and then processed, it:

a. will be completely clear

b. will be completely black

c. may still be used but will have a brown tint

d. may still be used but will show a decrease in density

e. may still be used but will now show an increase in density B. Will be completely black

Radiographs of the pregnant patient:

a. cause fetal injury

b. should never be made

c. should be made when there is a specific need

d. should only be made with certain precautions such as placing triple leaded aprons on the mother's lapC. Should be made when there is a specific need

A variation in the true size and shape of the object being radiographed is termed:

a. sharpness

b. distortion

c. resolution

d. magnification B. Distortion

The radiosensitivity of cells is dependent on:

a. mitotic activity

b. cell metabolism

c. degree of cell differentiation

d. all of the above answers are correct D. Mitotic activity, cell metabolism, degree of differentiation

Rectangular collimation is recommended because it:

a. increases film density

b. increases film contrast

c. decreases patient dose

d. deflects scatter radiation C. Decreases patient dose

Is is acceptable for the operator to hold the film in the patient's mouth if:

a. the patient is a child

b. the patient has a handicap

c. no film holder is available

d. the patient or parent grants permission

e. It is never acceptable for the operator to hold the film during exposure E. It is never acceptable for the operator to hold the film during exposure

Excessive vertical angulation causes:

a. elongation

b. overlapping

c. cone-cutting

d. foreshortening D. Foreshortening

All of the following are methods used to obtain the most geometrically accurate image EXCEPT:

a. the film should be parallel to the object

b. the target-to-film distance should be long

c. the object-to-film distance should be short

d. the central ray should be parallel to the object

e. the central ray should be perpendicular to the film D. The central ray should be parallel to the object

The size of the x-ray tube focal spot influences radiographic (choose the TWO correct answers):

a. density

b. contrast

c. resolution

d. magnification C. Resolution

D. Magnification (?)

The primary function of the developer is to:

a. remove exposed silver halide crystals

b. remove unexposed silver halide crystals

c. reduce solid grains to specks of silver halide

d. reduce crystals of silver halide to solid silver grains D. Reduce crystals of silver halide to solid silver grains

Which of the following could be done to correct a radiograph that is too dark after proper development.

a. increase milliamperage

b. decrease exposure time

c. place it back in the fixer

d. decrease development time

e. place it back in the developer B. Decrease exposure time

Occlusal radiographs are useful for all of the following EXCEPT:

a. for images of the TMJ

b. when the patient has trismus

c. when floor of the mouth sialoliths are present

d. for displaying large segments of the mandibular arch

e. when there is buccal-lingual expansion of the mandible A. For images of the TMJ

When taking extraoral radiographs, double intensifying screens and screen films are used to reduce:

a. density

b. contrast

c. exposure time

d. secondary radiation

e. target-to-skin distance C. Exposure time

Which of the following is least radiosensitive?

a. Red blood cells

b. Reproductive cells

c. Immature bone

d. White blood cells

e. Skeletal muscle cells E. Skeletal muscle cells

A long cone is used in paralleling or right-angle radiographic technique to:

a. reduce secondary radiation

b. avoid distortion of image shape

c. reduce magnification of the image

d. avoid superimposition of anatomic structures

e. facilitate correct vertical angulation of the cone C. Reduce magnification of the image

Increasing kilovoltage peak (kVp) will cause:

a. a decrease in density; the film appears darker

b. a decrease in density; the film appears lighter

c. an increase in density; the film appears darker

d. an increase in density; the film appears lighter

e. None of the above is correct, as kVp affects contrast D. An increase in density; the film appears lighter

Which one of the following factors would result in a dark radiograph?

a. The exposure time was too long

b. The developing solution was too cold

c. The developing time was not long enough

d. The films used were beyond the expiration date A. The exposure time was too long

Identify the cause of white spots on a processed radiograph.

a. Processing solutions are too warm

b. Fixer contacts film prior to processing

c. Developer contacts film prior to processing

d. Static electricity created with opening of film packet B. Fixer contacts film prior to processing

All of the following are characteristics of x-rays EXCEPT one. Which is the exception?

a. X-rays have a wavelength

b. X-rays can cause ionization

c. X-rays travel at the speed of sound

d. X-rays can produce an image on photographic film C. X-rays travel at the speed of sound

The length of the position-indicating device is changed from 16 inches to 8 inches. This change will result in the intensity of the x-ray beam to be:

a. half as intense

b. twice as intense

c. four times as intense

d. one-fourth as intenseC. Four times as intense

The imaginary line that passes from the top of the ear canal to the bottom of the eye is the:

a. occlusal plane

b. vertebral plane

c. Frankfort plane

d. midsagittal plane C. Frankfort plane

The lead foil sheet in a film packet acts to:

a. protect the film from saliva

b. protect the film from scatter radiation

c. protect the film from primary radiation

d. distinguish between the patient's right and left sides C. Protect the film from primary radiation

The latent period in radiation biology is the time between:

a. exposure and cell mitosis

b. subsequent doses of radiation

c. exposure of film and development

d. exposure to x-radiation and clinical symptoms

e. none of the above answers is correct D. Exposure to x-radiation and clinical symtoms

In manual film processing, the optimal time and temperature for the developer solution is:

a. 3 minutes at 55 degrees F

b. 5 minutes at 55 degrees F

c. 5 minutes at 68 degrees F

d. 10 minutes at 68 degrees F B. Five minutes at 55 degrees F

Identify the source of electrons used for the production of x-rays:

a. tungsten filament

b. molybdenum cup

c. tungsten target

d. copper stem A. Tungsten filament

The generation of x-radiation occurs:

a. in the copper stem

b. in the focusing cup

c. at the tungsten target

d. at the cathode C. At the tungsten target

Increasing the mA will cause:

a. an increase in density; the film appears darker

b. an increase in density; the film appears lighter

c. a decrease in density; the film appears darker

d. a decrease in density; the film appears lighter A. An increase in density; the film appears darker

Choose the answer that best describes long scale contrast:

a. also known as high contrast, seeing many blacks and whites

b. the type of contrast preferred for the diagnosis of interproximal caries

c. also known as low contrast, seeing many shades of gray

d. produced with low kVp settings C. Also known as low contrast, seeing many shades of gray

All of the following are indirect effects of radiation except:

a. direct alteration of molecules

b. production of free radicals

c. ionization

d. radiolysis A. Direct alteration of molecules

A free radical:

a. is an uncharged molecule

b. is reactive and unstable

c. combines with molecules to form toxins

d. all of the above D. is an uncharged molecule, is reactive and unstable, combines with molecules to form toxins

Which of the following most greatly reduces patient dose to radiation?

a. film speed

b. good operator technique

c. proper filtration

d. use of the lead apron A. Film speed

Increasing the time and mA settings on the exposure panel will:

a. increase the quality of radiation produced

b. increase the quality of radiation produced

c. decrease the quality of radiation produced

d. decrease the quantity of radiation produced B. Increase the quantity of radiation produced

Identify the most radiation-sensitive portion of the cell:

a. cell membrane

b. cytoplasm

c. nucleus

d. organelles C. Nucleus

Which of the following errors would contribute to a light film:

a. film was exposed to light

b. film was exposed backwards

c. film was contaminated with developer

d. all of the above B. Film was exposed backwards

The inverted "Y" represents the intersection of the nasal cavity and the:

a. canine fossa

b. maxillary sinus

c. zygomatic process

d. zygoma B. Maxillary sinus

You notice a horizontal radiopacity superior to the maxillary teeth on your patient's panoramic radiograph. This radiopaque structure is the:

a. tongue

b. palatoglossal air space

c. hard palate

d. coronoid process C. Hard palate

After manual processing a radiograph, you notice light, whiter spots on the film. This error is due to contamination with:

a. fixer solution

b. water

c. developer solution

d. a or b D. Fixer solution or water

A radiograph was exposed using too much vertical angulation. The resultant image will be:

a. foreshortening

b. elongated

c. overlapped

d. very dark A. Foreshortening

From the following, choose the cell that is most sensitive to radiation:

a. bone marrow

b. heart tissue

c. lung tissue

d. skeletal muscle A. Bone marrow

From the following, choose the cell that is lease sensitive to radiation:

a. reproductive tissues

b. intestines

c. nerve tissue

d. mucous membranes C. Nerve tissue

Dental radiographs machines using settings of 70 kVp or greater are required to operate with a minimum of:

a. 1.0 mm aluminum filtration

b. 1.5 mm aluminum filtration

c. 2.0 mm aluminum filtration

d. 2.5 mm aluminum filtration D. 2.5 mm aluminum filtration

Your patient's mandibular first molar has been treated by the endodontist. The pulp canal is filled with a slightly radiopaque material. Identify this restorative material:

a. silver points

b. gutta percha

c. composite

d. silicates B. Gutta percha

Which of the following is used to reduce the size and shape of the x-ray beam:

a. fast film

b. film-holding device

c. lead diaphragm

d. aluminum filtration C. Lead diaphragm

Which of the following reduces operator exposure to excess radiation:

a. fast film

b. distance

c. film-holding devices

d. proper filtrationw B. Distance

As you go from "D" speed film to "E" speed film, the exposure time should be approximately:

a. doubled

b. halved

c. remain the same

d. cut to one-fourth of the original time B. Halved


a. filament cup

b. tungsten target of the anode

c. tungsten target of the cathode

d. none of the above B. Tungsten target of the anode

Which of the following reduces the number of low energy x-rays (long wavelengths) in the beam:

a. collimation


c. milliamperage

d. kilovoltage B. Aluminum filtration

If a dental hygienist received a dose of 3 rads standing 6 feet from the source of radiation, how much radiation would they receive during the same exposure standing 3 feet away:

a. 1 rad

b. 3 rads

c. 9 rads

d. 12 rads D. 12 rads


a. target size

b. target-to-film distance

c. object-to-film distance

d. none of the above B. Target-to-film distance

A bite-wing radiograph is exposed properly using a time of 1.0 second and a PID of 8 inches. What time would be needed if the PID was changed to 16 inches:

a. 1/2 second

b. 1/4 second

c. 2 seconds

d. 4 seconds D. 4 seconds

Increasing the distance from the x-ray source gives increased protection because x-radiation:

a. weakens easily

b. is absorbed by air

c. loses speed with distance

d. loses intensity with distance D. Loses intensity with distance

The diameter of the useful beam at the end of the PID should not exceed:

a. 1.5 inches

b. 2.0 inches

c. 2.75 inches

d. 3.5 inches C. 2.75 inches

An early clinical sign of excessive exposure to radiation is:

a. jaundice

b. erythema

c. bleeding

d. hair loss B. Erythema

Radiographs left in fresh fixer solution for a long period of time:

a. become discolored

b. decrease in density

c. increase in density

d. display streaked images B. Decrease in density

A radiograph exposed to light will appear:

a. dark

b. clear

c. light

d. blurred A. Dark

When viewing a mandibular molar periapical radiograph, you could expect to see all of the following landmarks except:

a. mandibular foramen

b. external oblique ridge

c. submandibular fossa

d. internal oblique ridgeA. mandibular foramen

The purpose of the lead collimator is to:

a. reduce radiation exposure to the patient

b. absorb the long wave radiation

c. increase the amount of radiation needed to expose the film

d. all of the above A. Reduce radiation exposure to the patient

Identify the following restorative material that would appear the most radiopaque:

a. porcelain crown

b. stainless steel crown

c. amalgam restoration

d. gutta percha C. Amalgam restoration

Identify the chemical used to harden film emulsion:

a. sodium thiosulfate

b. hydroquinone

c. elon

d. ammonium a. Sodium thiosulfate

Your patient inadvertently moved during x-ray exposure. The resultant image would appear:

a. dark

b. blurred

c. elongated

d. all of the above B. Blurred

Which of the following are THREE functions of the cathode:

a. location of the focal spot

b. thermionic emission

c.converts bombarding electrons into photons

d. produces a cloud of electrons

e. absorbs excess hear

f. supplies the electrons necessary to generate x-rays B. thermionic emission

D. produces a cloud of electrons

F. supplies the electrons necessary to generate x-rays

A higher kVp setting will produce an image with which FOUR of the following characteristics:

a. low density

b. high density

c. low contrast

d. long-scale contrast

e. an image with many shades of gray B. High density

C. Low contrast

D. Long-scale contrast

E. An image with many shades of gray

Which of the following TWO characteristics decrease the magnification of an x-ray image:

a. increase the target-film distance

b. decrease the object-film distance

c. decrease the focal spot size

d. decrease patient movement

e. aim the central ray perpendicular to the long axis of the tooth and film A. Increase the target-film distance

B. Decrease the object-film distance

Place the following steps of automaric processing in the correct order:

1. water rinse

2. fixation

3. development

4. drying

a. 1, 2, 3, 4

b. 3, 1, 2, 4

c. 3, 2, 1, 4

d. 1, 3, 2, 4 C. Development, fixation, water rinse, drying

Underdeveloped film -film appears light

-inadequate development time or temperature

-depleted/contaminated developer solution

Overdeveloped film -film appears dark

-excess development time or temperature

-concentrated developer solution

Reticulation of emulsion -film appears cracked

-sudden temperature change between the developer solution and the water bath

Developer spots -dark spots on film

-developer solution contacts film before processing

Fixer spots -white spots on film

-fixer solution contacts film before processing

Overlapped films -white or black areas on film

-depends if happened in developer or fixer

Static electricity-thin, black branching lines

Fingernail artifact -black crescent-shaped marks

-emulsion damaged by fingernails

Fingerprint artifact -black fingerprint

-touching film

Scratched film -white lines on film

-film emulsion is removed

Light leak -exposed area appears black

Fogged film -film appears gray and lacks image detail and contrast

Anterior to focal trough Anterior teeth appear skinny and out of focus. "In is thin"

Posterior to focal trough Anterior teeth appear fat and out of focus. "Out is stout"

Incisive (nasopaltine) foramen Small, ovoid or round radiolucent area between roots of maxillary centrals

Median palatal suture Thin radiolucent line between maxillary central incisors

Canine (lateral) fossa Radiolucent area between maxillary canine and lateral incisors

Nasal cavity (fossa) Large radiolucent area above the maxillary incisors

Nasal septum Vertical radiopaque partition that divides the nasal cavity

Floor of the nasal cavity Dense radiopaque band of bone above the maxillary incisors

Anterior nasal spine V-shaped radiopaque area located at the intersection of the floor of the nasal cavity and the nasal septum.

Inferior nasal conchae Diffuse radiopaque projection within the nasal cavity

Maxillary sinus and floor of maxillary sinus Radiolucent area above the apices of the maxillary premolars and molars. Septa within the maxillary sinus: radiopaque lines

Inverted "Y" The intersection of the maxillary sinus and the nasal cavity

Maxillary tuberosity Radiopaque bulge distal to the 3rd molar region

Hamulus (hamular process) Radiopaque hook-like projection posterior to the maxillary tuberosity

Zygomatic process of maxilla J- or U-shaped radiopacity superior to maxillary 1st molar region

Zygoma (cheek, malar, zygomatic bone) Diffuse, radiopaque band extending posterior from the zygomatic process of maxillar

Genial tubercles Ring-shaped radiopacity below the mandibular incisors

Nutrient canals Vertical radiolucent lines

Mental ridge Thick radiopaque band that extends from premolar to incisor region

Mental fossa Radiolucent area above the mental ridge

Mental foramen Small ovoid or round radiolucency located in the apical premolar region

Mylohyoid ridge Dense, radiopaque band extending down and forward of molar region

Mandibular canal Radiolucent band surrounded by radiopaque border inferior in molar teeth

Internal oblique ridge Radiopaque band extending down and forward from the ramus

Eternal oblique ridge Radiopaque band extending down and forward from the ramus superior to internal oblique ridge

Submandibular fossa Radiolucent area in the molar region below the mylohyoid ridge

Coronoid process Triangular radiopacity superimposed or inferior to maxillary tuberosity

Mastoid process (of temporal bone) Radiopacity posterior and inferior to TMJ area

Styloid process Radiopaque spine anterior to mastoid process

External auditory meatus Opening in temporal bone superior and anterior to mastoid

Glenoid fossa (mandibular fossa) Radiopacity superior to mandibular condyle

Articular eminence (tubercle) Rounded radiopaque bone anterior to glenoid fossa

Infraorbital foramen Radiolucency inferior to the orbit

Orbit Radiolucent compartment with radiopaque borders superior to maxillary sinuses

Hard palate Horizontal radiopaque band superior to apices of maxillary teeth

Coronoid notch Radiopaque concavity distal to coronoid process

X-rays discovered by ____ in ____ while experimenting with Cathode ray Tube Roentgen in 1895

The shorter the group's wavelength, the ____the energy. Stronger

Difference: X-rays produce ______ ionization

The ejection of an electron from an atom Ionization

Ionization produces charged ion pairs or ____(another term for ion pairs) free radicals

Movement if electrons (-) along a wire toward a (+) charge which changes direction ____times per second. Many x-ray machines produce __ bursts or impulses of radiation per second. This electricity is called _____. 60, 60

AC electricity

1/2 second of radiation= how many impulses? 30

1 second= how many impulses 60 impulses

1/4 second= how many impulses 15 impulses

This term describes the number of electrons flowing. Counting electrons.

A.) Impulses

B.) Voltage

C.) AMPS AMPS (Amperes)

This term describes the "potential differences" between the (-) and (+) and therefore, the speed of force of the moving electrons toward the (+) charge. Voltage

Number of x-ray photons given off in a period of time. Quantity of the Beam

Describes the penetrating nature of the beam (involves wavelengths). Quality of the Beam

Only two affects penetration.

A.) Filtration

B.) Cathode

C.) mA

D.) kVp kVp and Filtration

____ is where electrons come from. Cathode

Which ones have no effect on the energy of the beam?

a.) mA

b.) Exposure Time

c.) kVp

d.) Aluminum filtration

e.) Distance a.) mA

b.) Exposure Time

e.) Distance

The number of photons increase or decrease with mA?

To produce quantity or quality or both? increase, quantity

Number of photons increase or decrease with exposure time?

Does exposure time affect quantity or quality or both? increase, quantity

The number of photons increase or decrease with kVp?

Does kVp affect quantity or quality or both? increase, Both quantity and quality

kVp: Shorter the wavelengths:

A.) More penetration

B.) Less penetration

C.) Does not make penetration A.) More penetration

Number of photons increase of decrease with Aluminum filtration?

Does aluminum filtration affect quantity or quality or both? decrease, Both quantity and quality

More Photons=More _____

Energy= more density

blackness

Aluminum lowers density. T or FTrue

A____ scale of contrast is mostly blacks and whites (High visual contrast) Short Scale

A___scale of contrast are many shades of gray (low visual contrast) Long Scale

A ___ scale of contrast results from more kVp and Aluminum. Long Scale

A ___scale of contrast results from less kVp and Aluminum Short Scale

This removes softer dangerous photons and hardens the beam. (Strong photons pass) Aluminum Filtration

Number of photons increase or decrease as beam spreads with Distance?

Does Distance affect quantity or quality? decrease, quantity

Density is affected by which of the following:

A.) mA

B.) exposure time

C.) kVp

D.) filtration

E.) Distance A, B, C, D, E

The film is more black as we increase mA.

True or False True

The film is more black as we decrease exposure time. True or False False. Increase exposure time and the film is more black.

The film density is decreased with distance and aluminum and they are both considered the short scale.

A.) Both sentences are true

B.) First Sentence is True, second is false

C.) Both are false

D.) First sentence is false, second is true. B. Distance is part of the short scale (More black)

Aluminum is part of the long scale (More grays)

What scale is used to see incipient caries? Short Scale

Area of sharpness means:

a.) small focal spot

b.) large target to film distance

c.) penumbra

d.) film and tooth parallel C.) Penumbra

All of the following produce the sharpest images with the least magnification except:

A.) Small Focal Spot

B.) Short object to film distance (OFD)

C.) Large target to film distance (TFD) or (SFD)

D.) Film and tooth parallel

E.) Large Focal Spot

F.) Beam perpendicular to film E. Large focal spot

What is the SLOB RULE?Same Lingual, opposite buccal

A hygienist is taking a second radiograph of a two-rooted tooth. On the second radiograph, the tube head was moved more distally, and one of the roots appears to have also moved more distally than the other root. Was the root that moved distally a buccal or a lingual root? Lingual

Inverse square law:

Original Energy/New energy=

(New Distance)2/( ?) (Original Distance)2

If the cone length is changed from 8 to 16, the original dose ______by factor of 4.

A.) Increases

B.) Decreases Decreases

(The answer is always 4xs more or less)

(Think of it like this: If the number goes from low to high like 8 to 16, the number decreases. It's the opposite of what you would think.)

If the cone length is changed from 16 to 8, the orginial dose _____ by factor of 4. increases.

If the cone length is changed from 12 to 6, the original dose _______ by factor of 4. increases

What opaque area is indicated:

A.) Pulp Chamber

B.) Periodontal Ligament Space

C.) Lamina Dura

D.) Canals C.) Lamina Dura

Review Pages #441-#447 in Board Review Book I SAID USE THE BOARD BOOK! LoL =) Are you awake?

A film comes out of the machine and it is all white. What most likely happened?

A.) Cone cut

B.) Backwards film placement

C.) Developer first

D.) Fixer first D.) Fixer first, unexposed. Fixer removes unexposed, undeveloped crystals. No energy took place.

A film comes out of the machine and it is all black. What most likely happened?

A.) Someone opened the film packet exposing the film to light

B.) Fixer first

C.) Cone cut A.) Exposed film

Pano Errors: When the anterior teeth are blurred and thin, what happened?

A.) Too Far posterior

B.) Too Far Anterior

C.) chin too high B.) Too far anterior

Pano Errors: When the anterior teeth are blurred and wide what happened?

A.) Too far posterior

B.) Too far anterior

C.) Nothing is wrong A.) too far posterior

Pano Errors: When there is a reverse curve of occlusion; condyles off side of image. (frown) This is the result of:

A.) Patients chin too high

B.) Patients chin too low

C.) The patient sneezed A.) Chin too high

Pano Errors: When the condyles are off the top of the image, this is a result of:

A.) Chin too high

B.) Chin too low

C.) Imposing air space B.) Chin too low

Pano Errors: When the tongue is not placed against the palate, what happens the pano?

A.) Becomes too dark

B.) Becomes too light

C.) Imposing air space

D.) Spinal Shadow C. Imposing air space

Pano Errors: When the patient slumped forward at an angle, what is the result:

A.)Imposing air space

B.) Imposing Spinal Shadow

C.) Imposing condyle space B.) Imposing spinal shadow

Digital radiographs have ___% less radiation than regular film. 80%

Discolored film is due to all except:

a.) exhausted developer

b.) exhausted fixer

c.) poor replenishment

d.) poor wash A.) exhausted developer. Exhausted fixer or poor replenishment after time, problem is poor wash is the cause.

Sodium thiosulfate is used in:

A.) Developer

B.) Fixer

C.) Wash

D.) Film Emulsion B.) Fixer

Elon & Hydroquinone is used in:

A.) Developer

B.) Fixer

C.) Wash

D.) Film Emulsion A.) Developer

Bromide is used in:

A.) Developer

B.) Fixer

C.) Film Emulsion

D.) Wash C.) Film Emulsion

This removes undeveloped, unexposed crystals.

A.) Developer

B.) Fixer

C.) Film Emulsion

D.) Wash B.) Fixer

This only turns exposed crystals to metallic silver.

A.) Developer

B.) Fixer

C.) Film Emulsion A.) Developer

What is another name for silver halide (Bromide) crystals on both sides of the film? Film Emulsion

Most common mechanism of damage in humans. Free radicals of water is called: Hydrolysis (Breaking down water molecules causes the most damage.)

Biological sensitivity to radiation:

Rapid turnover or __1___ rate of cells increases tissue damage. Undifferentiated cells have __2___damage

1.) Meiosis or Mitosis

2.) Increased or decreased Mitosis, increased

_____are more sensitive to radiation due to rapid cell mitosis associated with their growth.

A.) Adults

B.) Children

C.) Elderly Children

Time between x-ray exposure and maximum damage observed is called: Latent period

_____effects are only those that can be passed o future generations.

A.) Somatic

B.) Genetic B.) Genetic. (Anything else is somatic)

Adverse reactions of the body to x-radiation never return exactly to orginal state, therefore, accumulating to some degree over a lifetime is called: Cumulative effect

Gonadal exposure for the average complete mouth series is equal to ____days to ______ of normal background whole body radiation. 3 days to one week

What has the highest tissue sensitivity to radiation?

A.) Mucous Membranes

B.)Mature Cartilage

C.) Reproductive tissue

D.) Liver C.) Reproductive tissue

Name three tissues that have the highest sensitivity to radiation. Reproductive tissue, lymphoid tissue, bone marrow

Name three tissues that have medium sensitivity to radiation. Growing cartilage, growing bone, salivary glands

Name three tissue that have low sensitivity to radiation. Nerve tissue, skeletal muscle, heart

MPD stands for:Maximum Permissable Dose

Exposure in air: Roentgen converts to (in S.I. Units) _________ Coulomb/Kg

Absorbed Dose(tissue involved): Rad: ______(In S.I.Units) Gray (Gr.)

Dose Equivalent in man: Rem: _______ (in S.I. Units) Sievert (Sv)

True or False. There are no guidelines for x-rays. Based on individual findings. True

What is the ALARA principle? As Low As Reasonable Achievable

Film speed is the most effective method of protection. Each alphabetical film group is ___ times faster than the previous film group and needs half as much radiation exposure. 2 times faster. Ex: D-speed needs half as much exposure as C-speed and E-speed or E-plus needs half as much as D-Speed.

Panoramic intensifying screens reduce the amount of radiation (3-4 BWX) to the patient or the clinician?To the patient

This is a lead washer size beam and reduces scatter. Collimation

Beam size at the patient's face can be no larger than ____inches. _______ reduces patient's dose.2.75in, collimator

The rectangular collimation reduces the area of patient's skin surface exposed by __% to ___% over round 60-65%

With aluminum filtration: Must have at least ___mm of total aluminum filtration for up to and including 70kVp. Requires 2.5mm if machine can function above ___kVp. 1.5mm, 70kVp

Less volume of tissue is irradiated if ____ cone is used. long

Wall is mandatory if operator cannot stand at least ___ft from the scatter source(measured from the patient's head). 60ft.

Walls do not necessarily require lead lining. True or False TRUE

Lead apron absorbs ___% of the scatter that would have reached the reproductive tissues. Lead equivalent of ____mm 90%, .25mm

According to the MPD, the maximum amount of radiation a non occupational person may receive in one year is:

A.) 5 Sv/year

B.) 4 mSv/year

C.) 1mSv/year

D.) .005 Sv/yearD.) .005

According to the MPD, the maximum amount of radiation an non-occupational person may receive in one year is:

A.) .05 rem/year

B.) .005 rem/year

C.) .5 rem/year

D.) 5 rem/year C.) .5 rem/year

According to the MPD, the maximum amount of radiation an occupational person may receive in one year is:

A.) 5 rem/year

B.) 400 rem/year

C.) .5 rem/year

D.) .005 rem/year A.) 5 rem/year

According to the MPD, the maximum amount of radiation an occupational person may receive in one year is:

A.) .005 Sv

B.) .05 Sv

C.) 4 Sv

D.) 5 Sv B.) .05 Sv/year

All of the forms of energy comprising the electromagnetic family behave similarly except for which characteristic:

A.) all cause ionization of tissues

B.) all can produce "shadows"

C.) all travel in straight lines

D.) all travel at the speed of light A

How many impulses equal a 1/4 second exposure time?

a.) 6 impulses

b.) 10 impulses

c.) 15

d.) 50 C.) 15 impulses


a.) filament cup

b.) tungsten target of the anode

c.) tungsten target of the cathode

d.) the aluminum filter B

As you go from a D speed to an E speed film, the exposure time should be approximately:

a.) doubled

b.) halved

c.)cut to 1/4

d.) tripled B) halved

The mA setting controls which item(s) below:

a.) thermionic emission

b.) number of free electrons in the tube

c.) number of protons ultimately produced

d.) the density of the film

e.) contrast of the film A, b, c, d

Which of the following reduces the percentage of low energy x-rays in the beam?

a.) collimation

b.) aluminum filtration

c.) milliamperage B

The mean penetrability of an x-ray beam is related to all in the list below except:

a.) kVp

b.) filtration

c.) wavelength

d.) mA D

If radiology technician received a dose of 3 sieverts standing 4 feet from the source of radiation during an exposure, how many Sieverts would he receive during the same exposure standing 2ft away?

a.) 1.5 sieverts

b.) 6 sieverts

c.) 12 sieverts

d.) 27 sieverts C

A bitewing film is exposed properly using an exposure setting of 1 second with the x-ray source 8 inches from the patient. What time would be needed if the source was moved 16 inches away?

a.) 1/2 sec

b.)1/4 sec

c.) 2 secs

d.) 4 secs D

For optimal detection of incipient interproximal carious lesions (high contrast), which of the following machine settings is preferable?

a.) 90 kvp, 10 mA

b.) 85 kvp, 10 mA

c.) 75 kvp, 5 mA

d.) 65 kvp, 10 mA D

Which of the following factors control the quality of the x-ray beam and thus film contrast?

a.) exposure time

b.) aluminum filtration

c.) mA

d.) distance B

If a machine operated with good radiographic results at a setting of 15mA, 90kvp and 8 impulses, what exposure time should be used if the machine is changed to 10mA and 90 kvp?

a.) 120 impulses

b.) 90

c.)24

d.)12 D

Increasing the kvp results in:

a.) a long scale of contrast

b.) a short scale of contrast

c.) neither, it would have no effect A


a.) target size

b.) target film distance

c.) object film distance B

Occlusal radiographs are taken using which size film?

a.) #1

b.)2

c.)3

d.)4 D

Exposure time and mA control:

a.) quality of the beam

b.) photon wavelength

c.) number of x-rays produced

d.) cross section of the beam C

GBX II filters are needed for extraoral radiographs due to:

a.) double emulsion on film

b.) thicker emulsion

c.) larger film surface area

d.) film is more sensitive D

The optimum operating temperature for dental automatic processors is:

a.) 68 degrees F

b.) 82

c.) 95

d.)100 B.) 82

The primary purpose of sodium thiosulfate is to:

a.) preserve the image

b.) allow further blackening of the film

c.) remove the silver bromide crystals that have been developed

d.) remove the SBC that have not been developed D

Films not fixed for a long enough period of time will appear:

a.) to have black lines running through them

b.) to be brittle

c.) to have a brown tint

d.) white C

For reducing scatter radiation, the radiation beam at the patient's face should not exceed:

a.) 2.75 in

b.) 3.0

c.) 3.5

d.) 3.75 A

The minimum total aluminum filtration on a dental x-ray machine capable of operating at 70kVp and above is:

a.) 2.0 mm Al.

b.) 2.5 mm Al

c.) 2.75

d.) 3.00 B

Match cells to their sensitivity to radiation damage:

a.) Sperm cells 1.) radiosensitive

b.) spinal tissues 2.) radioinsensitive

c.) ovaries

d.) mature bone a.) 1

b.) 2

c.) 1

d.) 2

According to the NCRP, the maximum amount of radiation an occupationally exposed person may receive in one year is:

a.) 5 Sv

b.) 1mSv

c.) 4mSv

d.) .05 Sv. D

According to the NCRP, the maximum amount of radiation an occupationally exposed person may receive in one week is:

a.) 50 rem

b.) 5 rem

c.) 100 mrem

d.) 10 mrem C.

If an operator can stand 6 feet or more away from the ousrce of radiation scatter and out of the primary beam, no barrier wall is necessary.

A. True

B.) False A

Rank the following PIDs in order of safety provided from most safe to least safe.

a.) long, round

b.) short, round

c.) long, rectangular, led lined

d.) long, rectangular c,d,a,b

An ill defined radiolucency with a calcification at the apex of a vital root tip is:

a.) a traumatic bone cyst

b.) benign cemmental dysplasia (cementoma)

c.) osteogenic sarcoma

d.) condensing osteitis B

What is the proper thickness of the lead lining in radiographic lead aprons?

a.) .1 mm equivalent

b.) .25

c.) 1.0

d.) 2.5 B

Intensifying screens in panoramic cassettes are necessary to:

a.) increase sharpness

b.) decrease magnification

c.) increase film detail

d.) reduce patient exposure D

A film that has turned brown after the span of one year may have resulted from:

a.) insufficient wash

b.) extremely high developer temp

c.) fixing before developing

d.) the radiograph has simply aged and turned with time and is normal A

What is the most radiolucent dental material seen on dental radiographs?

a.) acrylic

b.) gutta percha

c.) amalgam

d.) aluminum temporary crowns A

What is the earliest clinical sign of an over exposure to x-radiation?

a.) loss of hair

b.) breakage of chromosome bonds

c.) mucosal sloughing

d.) erythema D

The greatest cause of human radiation effects in dental radiography involves:

a.) lysis of proteins

b.) destruction of enzymes

c.) free radicals of water

d.) mutations C

Cell sensitivity to radiation is most pronounced except:

a.) during mitosis

b.) during periods of increased metabolism

c.) during embryonic development

d.) in mature bone D

Tissue damage increases with decreased:

a.) exposure dose

b.) body coverage

c.) cell differentiation

d.) mitotic rate C

What is the effect of excessive vertical angulation?

a.) foreshortening

b.) elongation

c.) overlap A

In bisecting the angle technique, the central ray is directed perpendicular to:

a.) the film

b.) the long axis of the tooth

c.) an imaginary line bisecting the film and tooth

d.) the patient's Frankford Plane C

A panoramic image with a jack o lantern or extreme smile results from:

a.) chin too low

b.) chin too high

c.) patient placed too far anteriorly

d.) patient placed too far posteriorly A

Bisecting the angle can often lead to:

a.) elongation

b.)overlap

c.)film fog

d.) forshortening D

All can create film fog except:

a.) light leaks

b.) proper refrigeration

c.) chemistry

d.) faulty safelight B

Lisa deceided to change xray machines in her new operatory. The old machine had an 8" PID and was set at 26 exposure time and due to the knobs being broken she could not change it. If she decided to go to a

16" PID and a fully functioning xray machine, what would happen to the intensity if set at proper exposures?

a.) The intensity stays the same, but the exposure time would alter the density

b.) The intensity is directly proportional to a factor of 4 per every exposure time, thus meaning it is increased by 4.

c.) The exposure time is decreased by 4

d.) The intensity would be decreased by 4 D. Dont pay attention to the rest of the garbage. It is only asking about intensity and when the cone size is doubled, then the intensity is decreased by 4.

Which of the following has no antibody production associated with it?

a.) Type I

b.) II

c.)III

d.) IV

e.) none of the above, they all do D, Type IV or delayed hypersensitivity is the only reaction that does not have an associated antibody. Primary antibodies are

Type I=IgE

Type II= IgG or IgM

Type III= IgG

Identify which of the following is not a type of particulate radiation:

a.) alpha particles

b.)beta particles

c.) protons

d.) nucleons D

Identify the reduction in exposure time when changing from D speed film to E speed film:

a.) reduce exposure by 1/8

b.) reduce by 1/4

c.) reduce by 1/2

d.) reduce by 1/3 C

Angela is manually developing radiographs and does not notice a difference in solution temps. Identify the error that Angela would cause when a film is subjected to sudden temp changes (such as between developer and water bath)

a.) reticulation of emusion

b.) brown yellow stains

c.) fixer spots

d.) static electricity A

Fluorescent light and xrays produce the latent image on intraoral radiographs. The visible image on an extraoral film is the result of chemical processing of the exposed film.

a.) The first statement is True, the second is false

b.) The first statement is false, the second is true

c.) Both statements are True

d.) Both statements are False D

Model plaster or stone is sifted into the water before mixing in order to:

a.) retard setting time

b.) prevent entrapment of air

c.) dissipate heat

d.) avoid distortion of final product B

Approved fluoride components found in over the counter dentrifices include:

a.) sodium fluoride

b.) stannous fluoride

c.) sodium momofluorophosphate

d.) acidulated phosphate fluoride

1.) a,b,c

2.) a and d

3.) d only

4.) d only

5.) all the above1.) a,b,c

Acquired pellicle is initally derived from:

a.) saliva

b.) tooth structure

c.) bacterial products

d.) dietary components A

When a patient protrudes his tongue, deviation to the right side is noted. This suggests a disturbance in motor function of which of the following cranial nerves?

a.) V

b.) VII

c.) X

d.) XII D. Cranial Nerve 12 - Hypoglossal

Pinpoint pupils occurs in use of what drugs? morphine and related drugs, heroin, barbiturates

Dilated pupils occurs in what drugs? shock, heart failure, and other emergencies and in the use of hallucinogens and amphetamines, LSD, cocaine, or marijuana

Pick out the Suprahyoid muscles:

a.) Digastric

b.)Thyrohyoid

c.)Geniohyoid

d.) Stylohyoid

e.) Sternothyroid

f.) Omohyoid

g.) Mylohyoid a, c, d, g "Don't Get So Mad"

Pick out the Infrahyoid muscles:

a.) Thyrohyoid

b.)Mylohyoid

c.) Omohyoid

d.) Sternohyoid

e.) Sternothyroid a, c, d, e "TOSS"

Atom central nucleus and orbiting electrons

(proton +, neutron no charge, electrons -)

Nucleusmade up of protons and netrons

carry no charge

Electrons negative charge,

travel around nucleus in paths

shell closest to the nucleus has highest energy (k shell)

Molecule two or more atoms joined by chemical bond

Ion atom that gains or loses an electron and becomes electrically unbalanced

Process of Ionization converting an atom into ions

Ion pair when an electron is removed from an atom in the ionization process

Particulate radiation tiny particles of matter that possess mass and travel in straight lines and at high speeds

Electromagnetic radiation propagation of wavelike energy through space or matter

Properties of x-rays invisisble and weightless

travel in straight lines

travel in a wave like motion

travel at the speed of light (186mps)

ability to penetrate matter

can cause biological change

Tubehead aluminum disk (filters out non penetrating long wave)

lead collimator (restricts size of beam)

PID aims and shapes the beam

Cathode (-) left side negative

consist of tungsten wire filament

supplies the electrons necessay to generate xrays

Tungsten filament produces electrons when heated

(cathode side)

Molybdenum cup focuses electrons into a narrow beam and directs the beam towards the tungsten target

(cathode side)

Anode (+) right side

positive electrode

consist of wafer thin tungsten plate embedded in copper rod

converts electrons into xray photons

Tungsten targetserves as focal spot and converts electrons into photons

(anode side)

Copper stem funstions to dissipate heat away from the tungsten target

(anode side)

Kilovoltage regulates the penetrating power of the beam by controlling the speed of the electrons that travel between the cathode and the anode

higher kVp produces a beam with more energy or shorter wave lengths, higher settings increase intensity of the beam

Long wavelengths/low frequency useless, not strong and get absorbed

Short wavelengths/high frequency penetrate , more powerful

Wavelength determines the penetrating power of radiation

KvP terms quality

regulates penetrating power

wavelengths

controls speed

enegry

intensity/strength

KvP quality of beam penetrating ability

increase Kvp=more penetrating beam=increase in short wave

decrease KvP=decrease penetrating beam=decrease in short wave

KvP density increase KvP=higher density=dark film

decrease KvP=Low density=light film

KvP contrast (inversely related) low KvP=high contrast=black and white

high KvP=low contrast=shades of gray

KvP exposure time low KvP=high exposure time to maintain proper density/contrast

high KvP=low exposure time

high KvP=more penetrating beam=less exposure time

Milliamperage quanity, number, amount (does not effect contrast)

higher milliampere settings produce a beam with more energy, increasing the intensity of the beam

MA quanity increase MA=increase in the number of electrons present=increase in the number of xray photons

increase in MA=increase in production (regulates temp)

MA density increase MA=increase density=lighter image

MA exposure time (inversely related) aka milliampere seconds

increase MA=decrease exposure time

decrease MA=increase exposure time

Primary radiation penetrating xray beam that is produced at the target of the anode

Secondary radiation x-radiation created when the primary beam interacts with matter

Scatter radiation a form of secondary radiation

result of a xray that has been deflected from its path by interaction with matter

Mechanisms of injury Ionization- when xray strike patient tissue

Free radical formation-cell damage occurs through formation of free radicals/free radicals are formed when an xray photon ionizes water

Theories of radiation injury direct theory-cell damage results when ionizing radiation directly hits critical areas with the cell (frequently)

Indirect theory-xray photons are absorbed within the cell and cause the formation of toxins which damage the cell

Sequence of radiation injury Latent period (depending of time and total dose of radiation)

period of injury (a variety of cellular injuries may occur)

Radiation injury sequence, repair, and accumulation recovery period -depending on a number of factors, cells can repair the damage

cumulative effects- effects of radiation exposure are additive, unrepaired damage accumulates in tissues

Factors of Radiation injury total dose

dose rate

amount of tissue irradiated

cell sensitivity

age

Short tem effects associated with large doses of radiation in a short amount of time

Acute radiation syndrome (ARS) include nausea, vomitting, diarrhea, hair loss, hemorrhage

Long term effects small doses absorbed repeatedly over a long period of time

effects seen after years, decades, or generations (cancer, birth abnormalities, genectic defects)

Somatic cells effects all cells except the reproductive cells (ONLY ME)

Genecti cells effects reproductive cells (CHILDREN)

Biologic effects can be classified as either or

Radiosensitive cell that is sensitive to radiation

lymphoid tissue

bone marrow

testes

intestines

Radioresistant cell that is resistant (harder to effect)

salivary glands

kidney

liver

Critical organ an organ that if damaged diminishes the quality of a persons life

critical organs exposed during radiography skin

thyroid gland

lens of the eye

bone marrow

Units of measurement older

roentgen (r)

radiation absorbed dose (rad)

roentgen equivalent (in) man (rem)

SI (newer)

Coulombs.kilogram (c/kg)

gray (gy)

sivert (sv)

roentgen measures radiation by determining the amount of ionization that occurs in air (DOES NOT DESCRIBE THE AMOUNT OF RADIATION ABSORBED)

SI exposure stated in coulombs per kilogram

Dose measurement traditional unit is the rad

SI = gray

dose equivalent measurement 1gy=100rads

1SV=100 rems

added filtration an aluminum disk is placed between the collimator and the tubehead seal to filter out longer wavelengths. lower energy xrays from the xray beam

total filtration sum of inherit and added filtration

below 70kvp requires 1.5mm

above 70 kvo require 2.5mm

Collimation restricts the size and shape of the xray beam

reduces patient exposure

round or rectangular

PID extension of xray tubehead, used to direct the xray beam

may be conical, rectangular, or round

conical no longer exist

rectangular and round come in 8 or 16

the longer the least divergence the beam

the shorter the wavelength the more penetrating the x-rays

longer wavelength x rays are known as low energy or soft rays, most likely to be absorbed by the skin, low frequency rays

which us the most usuel beam, coming directly fromt eh target that is colimated and filtered primary x-ray bean

collimation removes long wavelenght x-rays

secondary rays are long wavelenght rays

on form of secondary rays that result when x-rays hit matter and scatter in different directions scatter rays

dense objects appear more radioopaque

dense ojbects absorb mroe x-rays or let x rays pass through them absorb

which radiation is more penetrating? characteristic radiation

if x-rays have less energy they will have a greater chance of being absorbed by the object result the object will apepar more radiopaque

x rays or photones are pdocued at the anode

characteristic radiation and ionization radiation causes electron to be ejected from its shell

the percent of energy released as heat at the tungsten target is 99%

cathode electrode is surrounded by the molybdenum focusing cup

affects the number of electrons being relased by controlling temperature of filament at the cathodemA

mA ranges from10-15

what is determined by film speed, exposure time, adn distance mA

what affects the density of x-ray film mA

overall darkeness or lighness of xray film densitiy

the more rays the more dense

what also effects film density exposure time, easier to change to alter density

how to fig out maS mas 1st x sec. 1st=ma 2nd x sec 2nd

controls the quality of radiation, speed of electrons travel fomr cathode to anode kVp

influence the penetration force or energy of x-rays kVp

setting range for kvp 65-110

setting determined by density of ojbect and contrast desired

the denser the ojbect the greater the kvp setting

more penetrating rays are needed to apss through denser objects kvp

what affects contrast kvp

is inverselty proportional to contrast kvp

as kVp increases the contrast decreases

which is high contrast 70kVp

shaes of gray contrast

many shades of gray low contrast

which setting is for periodontal evaluation increased kVp

which setting is for caries detection lowered kVp, higher ontrast

for every 15 percent increase in kVp the desntiy fo the radiograph will double

increasing kvp by 15 will allow reduction in exposure time by one half

which factores affect densith kvp, filtration, mA exposure time, and PID lenght

target-film distance increase distance, decrease density

factors that affect contrast on teh x-ray film increase kvp and increase filtration will decrease contrast

kvp affects the energy of photons produced in an xray machine, ma determines the nubmer of xrays produced both true

changing from 90 kvP to 75 kVp will

a. increase densitiy

b decrease desnity

c. increase contrast

d. decrease contrast c. increase contrast

x-ray penetration is influenced by which of the folloiwng?

a. amperage

b. voltage

c. filment temperature

d. wavelenght

e. b adn d above e b and d above

which of the following affect contrast?

a. distance

b. mA

c. kVp

d filtration

e. botha and b

f both c and d f. both c and d

what should be done when taking a second radiograph to inrease the contrast but keep the density the same as the original radiograph?

a. increase the kVp, decrease mA

b. decrease kVp, decrease exposure time

c. increase kVp, increase mA

d. decrease kVp, increase the exposure time d. decrease kVp, increase exposure time

using a small focal spot will produce a sharper image

focal spot will reduce penumbra (blur)

what decreases magnification increaseing the oject tube distance

what influence the exosure time changeign teh ojbect tube distance, target to fil distance

as distance is increased the expousre time is increased

if you increase the distance the xrays need to travel they will decrease in intesnity, so incrase exposure time to increase intensity

increase the ojbect tube distance

8-16" decrease intensity

increase epsoure time

decrease the object tube distance

16-8" increase intesnity

decrease exposure time

a radiographi sexposured uisng a 8" source fil distance, how is the intesnity affect if teh target fil distance is cnaged to 16" intensity will decrease, longer to travel, how many times you added the smaller PID legnth to itselt to total teh parger PID lenght, you added to itselt 2 times to get 16, therefore distance is 2, then squared is 4. so intensity decreased by 4 or 1/4

8" pid, expousre time 4 sec, if 2" pid is used what is the change in intesity? intesntiy increased, change in distance is 4 cuz 2 goes into 8 4 times, so 4 squred is 16, so the intesity increased to 16

a dental hygienist switches form 3" pid to 1" pid, what is the change in intesnity?

a. increased by 6

b. decreased by 6

c. increased by 9

d. decreased by 9 c. increased by 9

When exposure time or dose is given the following formula is used:

Exposure time (new)/Exposure time (old)=Distance (new)2/Distance (old)2 Sample Problem: A radiograph is exposed with a SFD of 8 inches with an exposure time of 1 second. What is the correct exposure time if the SFD is 16 inches? exp time(new)/1sec = 16" squared/ 8" scared, 16/8 to 2/1

exp time new/1 sec = 2 squared/ 1 squared

exp time/1sec= 4/1= 4 seconds

switch from 3" pid to 1"pid the expsure time for the 3" distance is 1 second what is the new exposure time? 1/9 seconds

a radiograph is exposured using TFD of 4" with an exposure time of 1 sec, the TFD is 8 " what is the correct exposure time? c. 4 seconds

shadow casting is decrased fil to ojbect distance, should be as close as possible to decrease magnification

tooth and fil should be parallel to decrease distortion

central ray should be perpendicular to film and tooth, decrease image distoration elgonation and foreshortening

produces less distored image than biseting angle technique

follow more of the principles of shadow casting paralelling

factors influencing image detal movment

filmfog

which of the following would cause film fog?

a. overexposure

b. udnerexposure

c. expsoure to light

d. excessive safelight d. excessive safelight

magnification can be reduced by

a. small focal spot

b. incrased fil to tube distance

c. decreased film to tube distance

d. increased fil to tooth distance b. increase film to tube distance

image detail is influenced by

a. patient movement

b. tube movement

c. film stabilization

d. both a and b above

e. all of the above e all of teh above

transfer of all energy to otuer orbiting electron thromsen scatter

transfer ofa ll energy to inner orbiting electro photoelectric

transfer of partial energy to out orbiting electron remaingin eneryg is scatter radiation compton scatter

most sensitive compoenent of the cells is the nnucleus

indirect effect of radtion on tissue is production of free radicals,

biologic effect depends on region exposed, rate of absorption

total amount absorbed

tissue repair is enhanced by reducing the dose

increasing the itme between doses

accumulated effect of radiation within tissues

radiation is not stored in tissues

mutation to future generation effect on DNA or nucleic acids genetic effect

injury to person exposed redness somatic effect

inuury from short term high doses acute effect

injury from long term doses chronic effect, cancer

time between expsoure and development of biological effect laten period

unit of radtiaon exposure rate or output of xray machin R

unit of absorbed dose at tissue rad 1 rad=.01 gray

relative biologic effect, compaire effects of various forms of radiaion in dentistyr Rem 1 rem - .01 sievert

younger immature cells, and high mitotic cells are more sensitive

mature cells and specialized cells are less sensitive

menmoic to remember order of radiosensitive tissues Ray likes yellow candy every recess day and most night

ray likes yellow candy every recess day and most nights reproductive

lymp

young bone marrow

circulatory

endocrine

respiratory

digestive

optic lens/ retina matrue cartilage

mature bone

nervous

what percent of radiation exposure is from background radiation? 80%

less than what percent is from man made radiation such as dental and medical? 20%

examples of background radiation increased altitudes

radionuclides in soil

cosmic radiation outer space

healing arts

nuclear energy

industrial products

tissues that are exposed most in denitsry thyroid

skin

bone marrow of mandible

eye

genetic tissues

most sensitive to radiation dna

direct effect of radiation on living tissues is compton effect, an indirect effect is the production of free radicals wihtin cells both true

mutations seen in future generations are known as

a. chronic effect

b. acute effect

c somatic effect

d. genetic effectd. genetic effect

which of the following cells ard tisseus are arranged from least sensitive to most sensitive to radiaton?

a. blood cells. young bone, salivary gland, nerve

b. muscle, lung, young bone, reproductive

c. lymph nodes, blood cells, lung nerver

d. nerve lung blood cells, young bone b. muslce lung, young bone, reproductive

amoutn of radiation the public and radiaton workers cna be exposed to in a calender yearmaximum permisible dose MPD, 5rem/yr .05sv

pregnant worker .5rem/year .005 sv

maximum amoutn of radiation an occupational worker can be exposed to based ont ehir current age5rem (N-18)

a patient comes to office for routine prophylaxis. they are taking pepcid, orthotyrcyclin, synthroid, and ibuprofen. what would you ask

a. do you ahve dry mouth,

b. do your msucles ache?

c. do you have a bleeding problem?

d. do you have breath odor? a. do you have dry mouth

operator protection film monitoring badge, stand 6 feet away behind lead barrier, neve hodl film for patietn, stand at right angle to beam or behind patient

patient protection lead apron w/ thyroid collor, fast film speed E speed

aluminum filter

collimator/lead diaphragm

long open ended rectangular PID

increase kVp

film holding device

proper technical and processing tecniques

ALARA principle as low as reasonbly achievable

x-rays most dangerous to fetus in first 2-6 weeks

Using E speed film rather than D speed allow operator to decrease exposure time by 1/2

A thyroid collar should not be used when exposing the following radiographs

a. bitewings

b. periapicals

c. panorex

d nonof teh above c panorex

the collimator is lead because it removes both long and short wavelenght x-rays

a. both statements and the reason are correct and related

b. both statemetn adn reason are correct but not related

c. the statment is correct, but the reason is not correct

d. the statement is not correct, but the reason is correct

e. neither the statement nore the reason is correct a. both the statement and the reason are correct and related

all of the following are true regarding operator protection against radiation except:

a. dental hygienist should stand at least 6 ft. from source of radtaion

b. detnal hygienist should stand behind a lead barrier

c. dental hygienist should only hold films for small children

d. dental hygienist should stand at righ angle to beam c. dental hygienist should only hold films for small children

periapical root to crown

pathology

bone loss

fractures

bitewing crowns of opposing arches

caries

level of alveolar bone

occlusalfractures

impacted teeth

cysts

sialolith

sizes 0

1

2

3

4 pedo

anterior

posterior

long bitewing

occlusal

extraoral xrays for TMJ view

water's projection sinus

cephalometic-ortho

growth paters

two view

lateral

and A/p projections

panorez impatctions

third molars

pathology

lateral jaw areas too large to be seen on periapical films fractures

pathology

which of the following is used to evaluate crestal bone loss?

a. panorex

b. periapical

c. bitewing

d. occlusal c. bitewing

all of the following are true regarding a panorex except

a. it is useful for caries detection

b. ghost images are seen

c. an intensifying screen is used

d. it lacks detail a. it is useful for carei detection

intensifying screens are used with extraoral radiographs becasue they enhance film detail

a. both statemetn adn reason are correct and related

b. both statement and reason are correct but not related

c. the statement is correct, the reason is not correct

d. the statement is not correct but the reason is correct

e. neither the statement nore th reason are correct c. the statement is correct but the reason is not correct

the larger the crystals the faster the speed

f film is the fastest

film composed of silver bromide crystals within emulsion

adhesive layer hodl emulsion on film

accumulation of silver ions with bromide ions is called the

a. visual image

b. latent image

c. developed image

d. preliminary image b. latent image

coverts silve crystals to black metalic silver, softens emulsion devloper

removes undeveloped and unexposed cyrstal, shrinks and hardens emulsion fixer

slob sme lingual opposite buccal

excessive vertical angulation foreshortening

insufficient vertical angulation elongation

incorrect horizontal angulation overlapping

herringbone patter visible and appear light a reversed film

double image, blurred patient movment.

double exposure, appears as superimposed on one antoher

overdeloped films or overxposed look dark

an underexposed or underdeveloped x-ray film will appear light

fixer is low black streak

The radiation dose to an individual is dependent on which of the following?

1. Type of tissue interaction(s)

2. Quantity of radiation

3. Biologic differences 1, 2, and 3

Place the following anatomic structures in order from anterior to posterior:

1. Trachea

2. Apex of heart

3. Esophagus Apex of heart, trachea, esophagus

The axiolateral, or horizontal beam, projection of the hip requires the cassette to be placed

1. in contact with the lateral surface of the body.

2. in a vertical position and exactly perpendicular to the long axis of the femoral neck.

3. with top edge slightly above the iliac crest. 1 and 3 only

What should be the radiographer's main objective regarding personal radiation safety? To keep personal exposure as far below the dose limit as possible

All the following can be associated with the elbow joint except

A. the capitulum.

B. the trochlea.

C. the tubercles.

D. the epicondyles. the capitulum.

The function of the 5-minute fluoroscopy timer is to alert the fluoroscopist that 5 minutes has elapsed.

Because of the anode heel effect, the intensity of the x-ray beam is greatest along the

A. path of the central ray.

B. anode end of the beam.

C. cathode end of the beam.

D. transverse axis of the IR. cathode end of the beam.

Which of the following quantities of filtration is most likely to be used in mammography?

A. 0.5 mm Mo

B. 1.5 mm Al

C. 1.5 mm Cu

D. 2.0 mm Cu A.

0.5 mm Mo

The moral principle that describes the radiographer's aspiration to do no harm or to allow no act that might cause harm to the patient is termed

A. beneficence.

B. nonmaleficence.

C. autonomy.

D. veracity. nonmaleficence.

here are many medicolegal terms with which the radiographer should be familiar. Beneficence refers to decisions and actions made to bring about good, ie, to benefit the patient. Nonmaleficence refers to the prevention of harm to the patient. Autonomy refers to the right of every individual to act with personal self-reliance. Veracity refers to telling the truth. (Adler and Carlton, 3rd ed, p 308)

The likelihood of adverse radiation effects to any radiographer whose dose is kept below the recommended guideline is

A. very probable.

B. possible.

C. very remote.

D. zero. C. very remote.

The lateral aspect of the obturator foramen is formed by the

A. ilium.

B. ischium.

C. pubis.

D. sacrum. ischium.

The lateral aspect of the foramen is comprised of the ischium and its rami, while its medial aspect is formed by the pubis and its rami. (Tortora, 11th ed, p 242)

The Bucky slot cover is in place to protect the

1. patient.

2. fluoroscopist.

3. technologist.

A. 1 only

B. 1 and 2 only

C. 2 and 3 only

D. 1, 2, and 3 C. 2 and 3 only

Which of the following will serve to increase the effective energy of the x-ray beam?

1. Increase in added filtration

2. Increase in kilovoltage

3. Increase in milliamperage C. 1 and 2 only

The esophagus commences at about the level of

A. C3.

B. C6.

C. T1.

D. T11. B. C6

The esophagus is a musculomembranous tube commencing at about the level of the cricoid cartilage, that is, C5-6. It is located posterior to the larynx and trachea and extends to about the level of T11, where it joins with the proximal stomach. (Bontrager and Lampignano, 6th ed., p. 447)

During a grand mal seizure, the patient should be

A. protected from injury.

B. placed in a semiupright position to prevent aspiration of vomitus.

C. allowed to thrash freely.

D. given a sedative to reduce jerky body movements and reduce the possibility of injury. A. protected from injury.

Which of the following imaging procedures do not require the use of ionizing radiation to produce an image?

1. Ultrasound

2. Computed axial tomography

3. MRI B. 1 and 3 only

To make the patient as comfortable as possible during a single-contrast barium enema (BE), the radiographer should

1. instruct the patient to relax the abdominal muscles to prevent intra-abdominal pressure.

2. instruct the patient to concentrate on breathing deeply to reduce colonic spasm.

3. prepare a warm barium suspension (98 to 105°F) to aid in retention.

A. 2 only

B. 1 and 2 only

C. 2 and 3 only

D. 1, 2, and 3 B. 1 and 2 only

When evaluating a PA axial projection of the skull with a 15° caudal angle, the radiographer should see

1. petrous pyramids in the lower third of the orbits.

2. equal distance from the lateral border of the skull to the lateral rim of the orbit bilaterally.

3. symmetrical petrous pyramids.

A. 1 and 2 only

B. 1 and 3 only

C. 2 and 3 only

D. 1, 2, and 3 D. 1, 2, and 3

A PA axial projection of the skull with a 15° caudad angle will show the petrous pyramids in the lower third of the orbits. If no angulation is used, the petrous pyramids will fill the orbits. Either PA projection should demonstrate symmetrical petrous pyramids and an equal distance from the lateral border of the skull to the lateral border of the orbit on both sides. This determines that there is no rotation of the skull. (Frank, Long, and Smith, vol. 2, 11th ed., p. 314)

An AP axial projection of the clavicle is often helpful in demonstrating a fracture that is not visualized using a perpendicular central ray. When examining the clavicle in the AP axial projection, how is the central ray directed?

A. Cephalad

B. Caudad

C.Medially

D. Laterally A. Cephalad

EXPLANATION: With the patient in the AP position, the central ray is directed cephalad 25° to 30°. This serves to project the clavicle away from the pulmonary apices and ribs, projecting most of the clavicle above the thorax. The reverse is true when the patient is examined in the PA position. (Bontrager and Lampignano, 6th ed., p. 202)

A backup timer for the AEC serves to

1. protect the patient from overexposure.

2. protect the x-ray tube from excessive heat.

3. increase or decrease master density.

A. 1 only

B. 1 and 2 only

C. 2 and 3 only

D. 1, 2, and 3 B. 1 and 2 only

Following the ingestion of a fatty meal, what hormone is secreted by the duodenal mucosa to stimulate contraction of the gallbladder?

A.

Insulin

B.

Cholecystokinin

C.

Adrenocorticotropic hormone

D.

Gastrin B.Cholecystokinin

EXPLANATION: About 30 minutes after the ingestion of fatty foods, cholecystokinin is released from the duodenal mucosa and absorbed into the bloodstream. As a result, the gallbladder is stimulated to contract, releasing bile into the intestine.

What is likely to occur if 25 rad is accidentally delivered to a recently fertilized ovum?

A. Skeletal anomalies

B. CNS anomalies

C. Spontaneous abortion

D. Childhood malignancy C. Spontaneous abortion

A film emerging from the automatic processor exhibits excessive density. This may be attributable to which of the following?

1. Developer temperature too high

2. Chemical fog

3. Underreplenishment B. 1 and 2 only

EXPLANATION: Excessive radiographic density may be a result of overdevelopment. Overdevelopment may be due to excessive developer temperature, resulting in chemical fog. Excessive density can also be a result of overreplenishment as a result of faulty microswitches or of feeding film into the processor "the long way" rather than "the wide way." (Fauber, p. 181; Shephard, pp. 151-153)

Which of the following groups of exposure factors would be most appropriate to control involuntary motion?

A. 400 mA, 0.03 second

B. 200 mA, 0.06 second

C. 600 mA, 0.02 second

D. 100 mA, 0.12 second C. 600 mA, 0.02 second

Incident It means falling upon or striking.

Photon It is the smallest quantity of electromagnetic radiation; an x-ray, gamma ray, or light.

Ionization The removal of an electron from an atom.

Scatter It involves a change in direction.

Dark Areas The __________ on a radiograph represent the area where the x-ray beam hit the film unaltered.

Physical Contact There is no _____________ between the photon and the atom.

Classical ScatterIt is also called unmodified scatter. It is when low-energy photon is absorbed by an outer shell electron and becomes excited. The photon is immediately released by the atom with same amount of energy as incident photon in order to return to ground state.

Thompson effect or Coherent scatter Classical scatter is also known as what?

Compton Effect It is a modified scatter in where moderate to high energy photon interacts with outer-shell electron. The photon is scattered with less energy, longer wavelength, and less penetration than the incident photon. It affects the contrast and detail of the image.

Recoil Electron The outer-shell electron is ejected is called compton or?

Fogging It is a form of noise that degrades the radiographic image.

Photoelectric Effect It is when moderate to high energy photon interact with inner-shell electrons and the incident photon is totally absorbed. It is about 4 - 6 times greater in bone than soft tissue, hence the large differential absorption; a major factor in radiographic contrast.

Photoelectron When the inner-shell electron is ejected, the ejected electron is called a?

Characteristic Photon It is dependent on the shell in which the electron is ionized.

Ionization What produces characteristic radiation?

Electron Binding Energy Photoelectric (PE) interactions are most probable when the _______________ is only slightly less than the energy of the incident photon.

25, 150 In the diagnostic range of ____ to ____ kVp, Photoelectric interaction predominates insofar as energy absorption from the beam is concerned.

Pair Production This interaction is beyond the realm or range of diagnostic x-ray. The high-energy photon interacts with nuclear electrostatic field.

1.02 Pair production occurs with photon energy of at least ____ mega electron volts (MeV).

1.) Negatron

2.) Positron In a pair production the incident photon disappears and reappears as two electrons. What are these two?

Negatron The negatively charged electron produced in pair production that eventually becomes an orbital electron.

Positron The positively charged electron resulting from pair production.

Annihilation Reaction It is the second stage of pair production. It exemplifies Einstein's law of conservation of matter and energy and is important in megavoltage radiation therapy.

2, .51 In an annihilation reaction, after the fraction of a second the positronium appears, it then disappears giving rise to ____ photons, each having an energy of ____ MeV.

Positronium Positron eventually combines with a free electron and forms a new particle called? It only exists for no more than 10^(-10) seconds.

Photodisintegration The process where high-energy photon interacts with the nucleus of an atom. Where the nucleus absorbs photon and emits a nucleon or other nuclear fragment.

10 Photodisintegration occurs with photon energy above ___ MeV?

a.) Compton Effect

b.) Photoelectric Effect

c.) Transmission of a Photon Of the ways an x-ray interact with tissue, only these are important in radiology. They are?

Differential Absorption A radiographic image results from the difference between x-rays absorbed photoelectrically and those transmitted. This is what you call a?

a.) Proper Techniques (kVp)

b.) Apparatus or Anti-Scatter Grids Methods to reduce noise in a radiograph?

Tomography What is the imaging modality that uses motion to bring into focus only the anatomic structure lying in a plane of interest, while structures on either side of that plane are blurred?

Superimposing Tomography avoids ______ structures as in conventional radiography.

Linear Tomography The simplest tomographic examination is?

Synchronous Movement The principle of tomography is based on the _____ of two of the three elements in a tomographic system: x-ray tube, object and image receptor.

Increased Patient Dose What is the principle disadvantage of tomography?

1,000 What is the average mrad for a nephrotomographic exposure?

Tomographic Amplitude (Arc or Angle) This is the total distance the tube travels.

Exposure Amplitude This is the total distance the tube travels during the exposure.

Blur What is the streaking or smearing that results in the loss of nearly all recorded detail of objects outside the focal plane?

Phantoms What do you call false images and are dangerous to the diagnostic process known as "blur edges"? They are produced by complex tomographic motions, circular, blur overlap, and displacement of blur margins.

Fulcrum The pivot point around which the motions of the tube and the image receptor are centered. It determines the focal plane and controls the section level.

Focal Plane It is the region within which the image exhibits satisfactory recorded detail and is controlled by the level of the fulcrum.

Section Thickness It is the width of the focal plane and is controlled by the exposure angle. It occurs in a plane parallel to the image receptor.

48 To avoid excessive shape distortion, the amplitude of the tube does not exceed how many degrees?

a.) Linear

b.) Curvilinear

c.) Elliptical

d.) Figure Eight

e.) Trispiral

f.) Hypocycloidal What are the types of tomographic movements?

Linear Motion It occurs when movement of the tube and image receptor are along a straight line.

Curvilinear Motion It improves on the linear motion by maintaining SID and OID and reducing magnification differences.

Elliptical Motion This eliminates some of the edge phantoms of circular motions.

Figure Eight Motion This movement eliminate most phantoms images, although their total tomographic amplitude is not as great as that of trispiral or hypocycloidal.

Trispiral and Hypcycloidal Motion This movement provides maximum tomographic amplitude, producing the thinnest possible section.

Linear or Unidirectional Tomogram This uses a basic x-ray table with the bucky tray and overhead tube connected by a metal connecting arm.

Panorex Unit The machine used for pantomography. Pantomography is used for curved body parts, most commonly the mandible, and for dental purposes.

Panoramic Tomography It is used to perform slit scan radiography of the curved surfaces of the face and head and uses only the perpendicular photons of the primary beam by using a lead mask to collimate the beam to a narrow slit.

Narrow-Angle Tomography/ZonographyThis is used when localization is necessary because the exact location of a structure is unknown or when a survey is being performed, for example, on a lesion of the lung or on a kidney.

Wide-Angle Tomography This is used when a lesion has been localized or a specific structure has been determined to require a more detailed examination and is useful in the examination of small bone structures, such as the inner ear.

Fluoroscope It consists of a specialized x-ray tube with an image receptor called the fluoroscopic screen. It was invented by Thomas Edison in 1896.

Fluoroscopy It is used mostly for studies that require observation of dynamic body functions such as swallowing by peristallic motion.

Fluoroscopic Input Screen It is similar to intensifying screens. It is composed of sodium-activated cesium iodide phosphors or crystals.

Phosphors It emits light photons after interacting with x-rays. They are coated onto the concave surface of the image intensification tube.

Thin Protective Coating It is applied to the input screen to prevent a chemical reaction with the photocathode.

Image-Intensifier Tube It is the complex electronic device that receives the image-forming x-ray beam and converts it into a visible-light image of high intensity.

Automatic Brightness Control This allows the operator to select an image brightness level that is subsequently maintained automatically by varying the kVp, mA, and pulse time.

Automatic Exposure Control Terminates the exposure when the proper radiographic density is obtained.

Photoemission This is the electron emission that follows light stimulation.

Thermionic Emission This is the electron emission that follows heat stimulation.

12 The tube-table distance shall be a minimum of ____ inches according to the National Committee on Radiation Protection and Measurement (NCRP).

Thin Transparent Adhesive Layer This bonds the input phosphor to the photocathode and prevents interaction of crystals of the input phosphor and the photocathode.

Cesium, Antimony A thin metal layer of the photocathode is usually composed of _____ and _____ compounds that respond to stimulation of input phosphor light by emission of electrons.

Output Phosphor The site where electrons interact and produce light. It is made of zinc cadmium sulfide crystals and a thin layer of aluminum is plated to it.

Flux Gain The ratio of the number of light photons at the output phosphor to the number of x-rays at the input phosphor. Increased illumination of the image is due to multiplication of light photons at the output phosphor.

Minification Gain The ratio of the square of the diameter of the input phosphor to the square of the diameter of the output phosphor. The compression of electrons from a large input screen to a smaller output screen.

Brightness Gain The ratio of the illumination intensity at the output phosphor to the radiation intensity incident on the input phosphor. It is the ability of the image intensifier to increase the illumination level of the image.

Candela Per Meter Squared The illumination intensity at the output phosphor is measured in?

MilliRoentgens Per Second The radiation intensity incident at the input phosphor is measured in?

Minification Gain, Flux Gain Brightness gain is equal to the product of?

Intensification Factor This applies to intensifying screens used in conventional radiography. It is a measure of the speed of the screen.

Multi-Field Intensifiers They provide greater flexibility in all fluoroscopic examinations.

Distortion The misrepresentation of object size and shape on a radiograph.

Elongation The anatomical part of interest appears bigger than normal.

Foreshortening The anatomical part of interest appears smaller than normal.

Noise or White Noise It is congruent with audio noise, such as static heard on frequencies between radio station. It has an inverse relationship to contrast.

Spatial Resolution The ability of imaging systems to accurately display objects in a two dimensional format. The grey scale represents a depth to the information in the image.

500, 8,000 Image intensifiers are capable of increasing image brightness ____ - ____ times.

Noise Random background information that is detected but does not contribute to image quality.

Frequency It is the raw data to which a Fourier transformation is applied to create the digital image.

Pixel The density and contrast of the digital image are controlled by varying the numerical values of each?

Dynamic Range It describes the concept of contrast as it is displayed on a soft copy monitor for digital images and is the number of gray shades that an imaging system can reproduce.

Spatial Resolution The ability of an imaging system to resolve and render on the image a small high-contrast object and quantifies the recorded detail of the digital image.

X, Y, and Z axis. Spatial resolution for digital images can be expressed in terms of three dimensions known as the?

Gray Scale Bit Depth It is a unit of measure of how many shades of gray can be displayed by each z-axis pixel in the x-y matrix.

Voxel In medical imaging, each pixel value corresponds to a three-dimensional volume of tissue known as a?

Post-Processing Refers to anything that can be done to a digital image after it is acquired by the imaging system. It is performed to optimize the appearance of theimage for the purpose of better detecting pathology and requires operator manipulation.

Window Leveling It is the ability of the computer to mathematically bring density differences into the visual range from extremely low and high-input doses that produce densities outside the range of vision.

Window Width It imaging is the ability of the computer to mathematically expand the visual density differences from similar input doses that would produce contrast far below the normal range of vision.

Quantum Noise Refers to a lack of sufficient incoming data for processing. In CR, term indicates an insufficient number of x-ray photons reaching the image receptor.

Automatic Rescaling It means images are produced with uniform density and contrast, regardless of the amount of exposure by eliminating signals outside collimation margins.

Automated Exposure Field Detection Part of the initial image processing sequence that eliminates signals outside collimation margins.

1.) Image Receptor Artifacts

2.) Object artifacts

3.) CR Reader Artifacts

4.) Printer errors What are some common types of artifacts?

Imaging Plate Artifacts These are the cracks that appear as areas of lucency on the image, adhesive tape residue and hair.

Backscatter These are created by x-ray photons transmitted through the back of the cassette and causes dark line artifacts.

Light Spots Usually caused by dust or other foreign material on the imaging plate. Results in a white grid-type pattern and white areas that correspond to the hinges.

Grid Orientation The grid lines are parallel to the plate reader's laser scan lines. Results in a moiré' pattern error.

Object Artifacts Can arise from the technologist's errors in patient positioning, x-ray beam collimation, and histogram selection.

Histogram Selection Radiographer must engage this appropriately before examination in order for the appropriate reconstruction algorithm to be applied to the final image.

Nonparallel or Asymmetric Collimation Margins It can cause exposure recognition errors, leading to histogram analysis errors because the signal outside the exposure field is included in the histogram.

Double Exposure Artifacts These occur when the technologist double exposes the CR plate, leading to both images being lost.

Laser Film Transport Artifacts It is caused by uneven transport of film material through the laser imaging system.

Dropout Artifacts Result of dust accumulation in the CR or laser imaging unit components (polygonal mirror, light gate, or other reflective surfaces).

CR Scanner MalfunctionIt is caused by memory problems, digitization problems, or communication errors and results in skipped scan lines, missing pixels, and distorted images.

Computed Radiography Cassette-based digital imaging is the digital acquisition modality that uses storage phosphor plates to produce projection images. It can be used in standard radiographic rooms just like film/screen.

Cassette It consists of a durable, lightweight plastic material. A light-proof container that protects an imaging plate from light and handling and is backed by a thin sheet of aluminum that absorbs x-rays.

Imaging Plate It is housed in a cassette. The material must have the ability to store and release the image information in a usable form.

Barium Fluorohalide Bromides and Iodides with Europium Activators The most common phosphor with characteristics favorable for CR is?

Computed Radiography Reader The cassette is fed into this that removes the imaging plate and scans it with a laser to release the stored electrons.

Light Collecting Optics Emitted light from the IP, is channeled into a funnel like fiber optic collection assembly and is directed at the photodetector, photomultiplier tube (PMT) photodiode (PD) or charge-coupled device (CCD).

Photodetector It receives light from the fiber optic collection assembly, and transmits a time-varying analog signal to a computer system.

1.) Protective Layer

2.) Phosphor or Active Layer

3.) Reflective Layer

4.) Conductive Layer

5.) Color Layer

6.) Support Layer

7.) Conductor Layer

8.) Light Shield Layer

9.) Backing Layer What are the layers of the imaging plate?

Protective Layer A very thin, tough, clear plastic that protects the phosphor layer.

Phosphor or Active Layer Holds the Photostimulable phosphor (PSP), which is the active component in the plate.

Reflective Layer It sends light in a forward direction when released in the cassette reader. This layer may be black to reduce the spread of stimulating light and the escape of emitted light.

Conductive Layer The material in this layer absorbs and reduces static electricity.

Color Layer It is located between the active and support layers of the IP that absorbs the stimulating light but reflects emitted light.

Support Layer A semi-rigid material that gives the imaging sheet some strength and a base on which to coat the other layers.

Conductor Layer It grounds the plate to eliminate electrostatic problems and absorb light to increase sharpness.

Light Shield Layer It prevents light from erasing data on the imaging plate or leaking through the backing, decreasing the spatial resolution.

Photostimulable Luminescence It is defined as light produced by a phosphor (active layer) when struck by light or x-ray photons. It occurs following x-ray exposure. However, it also occurs some time later when exposed to a different light source (laser beam).

Diameter The ___________ of the laser beam affects the spatial resolution of the CR system.

Raster Pattern Scanning of the IP by a laser occurs in a ____ as the plate is fed through the processor.

Post-processing It is performed to optimize the appearance of the image for purpose of better detecting pathology.

Image Flip and Image Inversion Reorients image presentation and makes white black and black white.

Sensitivity Various computed radiography images receptors is different for each manufacturer.

0.1, 100Exposure sensitivity of the imaging plate ranges from __ mR up to maximum of __ mR.

Exposure Indicator In order to evaluate the exposure for CR image, most manufacturers have an ______ that provides information on the average amount of radiation used for an image.

Fuji _____ uses a sensitive number (S number) that is related to the amount of amplification required by the PM tube to adjust the digital image.

Kodak ______ CR indicator system is called the exposure index, which is directly proportional to the radiation striking the IP.

Agfa _____ system uses a log median exposure (LgM), it compares the exposure level of an image to a baseline established for the department.

1.) Part selection

2.) Technical factors

3.) Equipment selection

4.) Grid selection

5.) Collimation What are the exposure selection factors?

Part Selection Selecting the proper body part and position is important for proper conversion to take place, If improper part and/or position selected, the computer will misinterpret the image.

Image Recognition It is accomplished through complex mathematical computer algorithms.

Kilovolt Peak Selection It must be chosen for penetration and the type and amount of contrast desired.

Millamperage Seconds Selection It is still critical in determining proper digital image receptor exposure.

Quantum Mottle or Quantum Noise This occurs when an insufficient light is produced and the image is grainy.

Digital Image Histograms They are a graphic representation of the exposure to the image receptor.

1.) Type

2.) Size The important factors should be considered when selecting the CR Imaging cassette.

1.) Standard

2.) High Resolution Manufacturers produce these types of imaging plates.

High Resolution Imaging Plates Most often used for extremities, mammography and other exams requiring increased detail and should be marked on the outside to indicate type of IR.

Pixel Size The ______ is an important factor in determining the resolution of the displayed image.

1.) Part size

2.) kVp desired

3.) Scatter cleanup desired

4.) Grid frequency Grid use in CR occurs more often due to the sensitivity of the IP to scatter. The grid selection will depend on what factors?

Moiré Effect/Pattern A wavy artifact pattern occurs when the grid lines and the scanning laser are parallel.

Grid Frequency It is the number of grid lines per centimeter or per inch.

80, 152 Typically grid frequency is between __ - __ lines/in.

103, 150 Some manufacturers recommend no fewer than ___ lines/in and strongly suggest grid frequencies greater than ___ lines/in.

Grid Ratio The relationship between the height of the lead strips and the space between the lead strips.

Higher The ______ the ratio, the more scatter radiation absorbed and the more critical the positioning.

Focus _________ grids consist of lead strips angled to coincide with the divergence of the x-ray beam and must be used within a specific distance using a precisely centered beam.

48 Parallel grids are less critical in beam centering but should not be used at distances less than ___ inches.

Smaller The ______ the cassette being used, the higher the sampling rate.

Collimation This reduces the area of the irradiation and the volume of tissue in which scatter can be created.

Shuttering It is the post-exposure image manipulation. This technique is not a replacement or proper pre-exposure collimation.

Black Background A ________ can be added around the original collimation edges, eliminating the distracting white or clear areas.

Transport system, Dryer system, Replenishment system, Circulation system, Temperature control system The automatic processing components are considered complex and utilize several subsystems to completely process a radiograph that include?

Developing Stage of processing which the latent image is converted a visible image. It is very short and highly critical to the film processing sequence.

Fixing Removes remaining silver halide from emulsion and hardens gelatin.

Washing Removes any excess chemicals from the previous processing steps.

5 Wash water should be maintained at __º F lower than developer temperature.

20 Washing typically occurs in ___ seconds.

26 Drying typically occurs in ___ seconds?

Transport System What is designed to move film through components of the processor?

Rollers, Transport rack subassembly, Drive Motor Subsystem Transport system consists of what principle subsystems?

Transport Rack Subassembly They are easily removable and provide for convenient maintenance and efficient cleaning of the processor and uses guide shoes to guide film around bends.

Turnaround Assembly Systems that consist of a master roller, planetary rollers, and guide shoes is called a? It is located at the bottom of the transport rack assembly.

Crossover Rack As film exits the top of the rack assembly, it is guided to the adjacent rack assembly through a?

Drive Motor Subsystem A chain, pulley, or gear assembly transfers power to the transport rack and drives the rollers.

Thermocouple or Thermistor Temperature is monitored at each stage by a ______ and is controlled thermostatically by a controlled heating element in each tank.

Replenishment System Replaces chemicals that are depleted in developer and fixer. It is accomplished by metering the proper quantities of chemicals into each tank to maintain volume and chemical activity.

Circulation System Designed to continuously pump the developer and fixer in order to maintain constant agitation within each tank and uses water that is circulated through the wash tank to remove all of the processing chemicals from the surface of the film before drying.

Negative Internal Air Pressure Dryer systems should be run at a _____ so that air is continually being sucked in and the fume-laden moist air vented externally.

Pi Lines Roller marks that occur at 3.1416 (represents one revolution of a roller) inch intervals due to dirt or chemical stain on rollers.

Dirty Rollers It causes emulsion pick-off and gelatin buildup result in sludge.

Curtain Effect Chemical fog that is caused by chemistry that is not squeezed out properly from film that runs up the edge of the film.

Wet-Pressure Sensitization Produced in the developer tank, pressure from irregular or dirty rollers produce small circular patterns of increased optical density (OD).

Kink Marks Characteristic artifacts can be caused by improper handling or storage either before or after processing. It can be caused by rough handling or abrupt bending.

Hyporetention It is caused by a long storage time and reveals a yellow-brown stain that slowly appears on the radiograph.

Exposure Artifacts Generally associated with the manner in which the radiographer conducts the examination.

Base Layer The layer farthest from the film and is 1 millimeter thick. It serves as a mechanical support for the active layer.

Reflective Layer It is the layer between the phosphor and the base that is made of a shiny substance such as magnesium oxide or titanium dioxide.

Calcium Tungstate It is an active substance of most phosphor screens before1980's and is embedded in a polymer matrix and slower of the two.

Rare Earth Composed of gadolinium, lanthanum, and yttrium and is newer and faster screens.

Protective Coating The layer of the radiographic screen closest to the radiographic film. It helps to eliminate the buildup of static electricity.

Luminescence It is the emission of light as a direct result of some outside excitation or stimulation.

Fluorescence It occurs when visible light is emitted only when the phosphor is stimulated.

Phosphorescence It occurs if the phosphor continues to emit light after stimulation.

Spatial Resolution The ability to accurately image an object by the use of intensifying-screens.

Film Screen Contact This is one of the most common screen resolution problems is caused by poor contact.

Image Noise It appears on a radiograph as a speckled background. It occurs most often when fast screens and high kVp techniques are used.

Quantum Mottle It is caused by an insufficient quantity of photons striking the intensifying screen.

Optical Density Degree of blackness present at any given point on the film. It has a numeric value and can be present in varying degrees from completely black to almost clear.

Clear Optical Density of 0.2 means that the film is almost?

Controlling Factors Should be used as the principle method of adjusting for insufficient or excessive density.

Milliamperage-seconds (mAs) It is used as the primary controller of image receptor exposure and film density. It is the primary controller of x-ray quantity.

kVp A change in __ alters the intensity of the beam when the mAs and other factors remain the same.

Focal Spot Size Calibrated by the manufacturer and there should be no difference between large and small sizes.

Source-to-Image Receptor Distance (SID) It alters intensity of the beam reaching the IR according to the inverse square law.

Anode Heel Effect Alters the intensity of radiation, and therefore the density, between the anode and cathode ends of the x-ray tube. The IR exposure is always greater at the cathode end.

Filtration Alters the beam intensity affecting the image receptor exposure and film density.

Beam Restriction The collimating or reducing of the primary beam field size reduces the total number of photons available thus reducing the amount of scatter radiation and therefore reducing the overall image receptor exposure and film density.

Anatomical PartThe patient is the prime attenuator of the beam, thus the ______ being examined has a great influence on the IR exposure and film density .

Grids Absorb scatter, which would otherwise add exposure to the IR and density to the film. A tool used to improve image contrast by reducing the level of scatter radiation.

Film Processing The condition of the ____ solutions can dramatically alter film density.

Radiation Fog This reduces the contrast of the radiographic image.

1.) Milliamperage-seconds (mAs)

2.) Kilovoltage Peak (kVp)

3.) Field Size Limitation

4.) Grids

5.) Intensifying Screen Speed

6.) Source-to-image-distance (SID)

7.) Object-to-image receptor distance (OID) What are the radiographic density factors?

Exposure Time Radiographic _____ is usually kept short as possible to minimize motion blur due to patient movement.

Penetration The ability to pass through an object and reach the x-ray film to expose it.

Double If kVp increased by 15% radiographic density will roughly _____.

Half If kVp decreased by 15% radiographic density will be roughly _____.

Field Size Limitation It affects the level of scatter radiation and is controlled by the radiographer.

Intensifying Screen Speed It is determined by the relative number of x-rays that interact with the phosphor, and how efficiently x-ray energy is converted into visible light that interacts with the film.

Diagnostic / Therapeutic Medical x-ray units are classified as?

a.) The energy of X-rays produced.

b.) The purpose for which those X-rays are intended. X-ray machines are usually identified according to?

a.) X-ray tube

b.) Operating console

c.) High voltage generators What are the three main components of x-ray imaging systems?

Fixed Equipment Any imaging system that is designed exclusively for "in department use".

25, 150 Diagnostic x-ray imaging systems usually operate at maximum voltages ranging from _____ to _____ kVp.

10, 1200 Diagnostic x-ray imaging systems usually operate at tube currents ranging from _____ to _____ mA.

a.) Radiographic imaging system

b.) Fluoroscopic imagining system

c.) Patient supporting examination tableA general purpose x-ray examination room contains?

Special Angiointerventional Procedures Rooms with a fluoroscope and two or more overhead radiographic tubes are used for?

a.) Dedicated chest unit

b.) Tomographic unit

c.) Mammographic unit

d.) Computerized tomography units

e.) Special studies suite (Angiographic Suite)

f.) Magnetic resonance imaging suite

g.) Panoramic dental and facial units

h.) Radiation therapy simulator units

i.) Urologic units Specialized diagnostic equipment includes?

Dedicated Chest Unit Automates radiography by combining an upright Bucky with an automatic film handling mechanism.

Dedicated Head Unit Specialized diagnostic equipment for cranial studies.

Tomographic Unit Specialized diagnostic equipment that has tubes that move in an arc during exposure.

Magnetic Resonance Imaging Suite A diagnostic equipment that has computerized sectional images using magnetism and radio frequencies.

Patient-Supporting Examination Table It may be flat or curved and must be uniform in thickness. Has to be transparent to x-rays as much as possible.

Radiation Area The ideal room design has to make it possible to reach the console without having to enter the ________?

High Voltage Generator It may be housed in equipment cabinet positioned against the wall and is always close to the x-ray tube. Some are placed in false ceilings, out of sight.

Digital Fluoroscopy It is conducted in much the same manner as conventional fluoroscopy but with the addition of a computer, multiple monitors, and a more complex operating console.

Pulse-Progressive Fluoroscopy Images from DF are obtained by pulsing the x-ray beam in a manner called ?

Thin Film Transistor (TFT) DF is achieved through the use of a _____ in contact with the image intensifier output anode screen. It is a pixelated unit with a photodiode connected to each pixel element.

Flat Panel Image Receptors (FPIRS) Thin Film Transistor (TFT) is also referred as?

Scintillator A ______ is a material that emits light when exposed to ionizing radiation.

Video Analog to Digital (ADC) A type of acquisition that receives output signal from the image-intensified digital receptor and accepts the continuously varying signal, the analog signal, and digitizes it.

Charged Coupled Device (CCD) It is a semiconducting device capable of storing a charge from light photons and striking a photosensitive surface and has the ability to store freed electrons, thus storing the image in a latent form. It's primary advantage is the extremely fast discharge time.

Direct Selenium A semiconductor with excellent photon detection and spatial resolution and uses a high voltage charge.

Flat Panel Image Display This is rapidly replacing the cathode ray tube used in conventional radiography and fluoroscopy (CRT).

a.) Easier to view and manipulate

b.) Provides better images

c.) Can be readily mounted in angiography and OR rooms What are the advantages of flat panel image display?

Output Signal It is the signal from the image-intensified digital image receptor is transmitted to an Analog-to-Digital Converter (ADC).

a.) Low Dose Rate

b.) Static Images

c.) Spot Images What are some techniques for reducing patient and operator exposure?

Video Camera Tube What is the most commonly used fluoroscopic viewing system?

Video Camera Charged-Coupled Device It is a semiconducting device that stores a charge from light photons striking a photosensitive surface and stores the image in a latent form.

Cathode Ray Tube (CRT)It has a fluorescent phosphor coating on the inside of the front screen and an electron gun with deflecting and focusing electromagnets.

Cine Film Systems What has a cinecamera positioned to intercept images produced by output screen of intensifying screen? It requires about 90% of the image intensity for proper exposure levels and uses both 16 and 35 mm formats.

Cinefluoroscopy Cine film systems is also referred to as?

Video Recorders It requires high resolution cameras, tape and monitor for the significant increase in resolution and works like a home video system.

Cassette-Loaded Spot Films This is positioned between the patient and the image intensifier. It requires a higher patient dose but produces high image quality.

Photospot Camera It is similar to a movie camera but exposes one frame at a time. This receives image from the output phosphor of the image-intensifier tube and therefore requires less patient exposure than cassette-loaded spot films.

70, 105 Photospot camera uses film sizes of ___ - ____ mm.

Quality Control A comprehensive set of activities designed to monitor and maintain systems or equipment that produce a product.

1.) Performed safely

2.) Appropriate for the patient

3.) Performed efficiently

4.)Producing high-quality images Quality Control is performed to ensure that radiologic procedures are?

1.) Acceptance testing

2.) Routine maintenance

3.) Error maintenance The major categories of QC testing include?

Acceptance Testing Performed on newly installed or majorly repaired equipment . It is used to determine whether the equipment is performing within the vendor's specifications and as promised.

Routine Maintenance Performed to ensure that the equipment is performing as expected.

Error Maintenance Corrective actions are performed for errors that occur in equipment performance.

American College of Radiology The organization that requires compliance with standards of practice to ensure quality in any imaging system. Provides recommendations on system tests that must be performed by service personnel (venders, manufacturers) and/or radiologic technologists, and radiation physicists.

Federal Quality Control Standards These are uniform for all manufacturers have yet to be implemented because CR and DR systems are relatively new.

1.) Technologist

2.) Service personnel

3.) Radiation or Medical Physicist Common computed radiography quality control activities, schedules, and responsibilities for?

1.) Cleanliness of cassettes/receptors

2.) Cassette integrity

3.) Ensure imaging plates have been completely erased

4.) Verify digital interfaces and network transmission

5.) Check laser printer functionality, cleanliness, paper, ink, and artifacts produced by dirt or fingerprintsWhat are the daily responsiblities of technologists?

1.) Verify monitor calibration (CRT only)

2.) Clean CRT screen, keyboard, and mouse

3.) Clean and inspect receptors

4.) Follow any manufacturer recommended QC tests

5.) Inspect CR reader What are the weekly responsiblities of technologists?

1.) Perform reject/repeat analysis survey

2.) QC out of standard images

3.) Inspect and clean all image plates (IPs) What are the monthly responsiblities of technologists?

1.) Testing to establish accuracy and reproducibility

2.) Phosphor accuracy testing

3.) Image processing parameters

4.) Tests the system for correct positioning and processing

5.) Screen erasure

6.) Spatial Frequency response testing What are the responsibilities of Service Personnel?

1.) Perform acceptance testing of new equipment

2.) Reviews departmental images

3.) Reestablish baseline values

4.) Check exposure indicator's accuracy with calibrated ion chamber

5.) Determines exposure trends

6.) Analyze repeat rates

7.) Reviews QC records

8.) Analyzes service history of routine maintenance and repairs What are the responsibilities of the Radiation or Medical Physicist?

Repeat Analysis Program It serves to catalog rejected images and determine the nature of the repeat so that repeat images can be minimized or eliminated in the future. It provides important data about equipment and accessory performance, departmental procedures, and the skill level of the technical staff.

4, 6 Department repeat rates should not exceed __ - __%.

Centralization The ___ of the location is the most convenient and important in the darkroom plan.

Unexposed Film Material Construction should provide suitable storage facilities for ______.

Light Tight DoorPersonnel access to the darkroom by means of a ____.

Pastel and Light Darkroom walls should be painted in ______ colors to increase the reflectance of the light emitted from the safelight.

1.) Lighting (Safelight)

2.) Overhead Lighting (White light)

3.) Entrance

4.) Pass boxes

5.) Ventilation

6.) Storage film bin

7.) Counter space and other work surfaces

8.) Processor

9.) Drains What are the components of a darkroom?

Sodium Vapor Orange-yellow light. It should be installed near the ceiling, facing up and must be installed indirectly to illuminate the working area.

GBX Filter Must be a 7-15 watt bulb and located at least 4 feet from the working area.

Overhead Lighting It is the standard white light that normally illuminates the interior rooms of hospitals and clinics.

Single Door It should be equipped with an electric lock on the door that will not open when the film bin is open.

Pass Boxes Operates on interlocking system; when opened on darkroom side will not allow exposure room side to open. Usually partitioned so that exposed films can be entered on one side and unexposed films on the other.

Storage Film Bin Store unexposed films of different sizes after film package has been opened and protect film from white light exposure.

Counter Space Should be grounded to reduce risk of static electricity.

Static Electricity______ creates sparks that emit white light which could create artifacts on the processed image.

Processor Its purpose is to mechanically develop exposed radiographs to manifest image. Usually film feed tray is contained within darkroom and output tray outside the darkroom.

Copper, Brass Floor drains must not be made of ___ or ___ because of the corrosive properties of the processing chemicals

Bremsstrahlung Radiation Process or Brems Radiation It is also known as braking radiation. The bombarding electron may be decelerated by being swept around a nucleus of a target atom, and the energy lost by the electron is radiated as an x-ray photon.

Very Strong Electrostatic Force What causes the electron to suddenly slow down?

VelocityThe higher the ______________ of the electron when it interacts with an atom, the greater the energy of the radiation that may be produced.

Strong Positive Nuclear Field The ___________ of the target atom (i.e., tungsten) attracts the negatively charged high speed projectile electron.

1.) Deviate from its original path.

2.) Slow down or decelerate.

3.) Loose some of its kinetic energy. When the negatively charged high speed projectile electron gets attracted because of a positive nuclear field it causes it to?

Characteristic Radiation This type of radiation interacts with inner shell electrons mostly from the K-shells and low energy photons. It composes about 20% of most x-rays being produced and highly penetrating in a diagnostic range.

1.) The speed of the electrons.

2.) How close the electron approaches the target nucleus. The amount of braking and deceleration is dependent upon?

Voltage By increasing the _____ applied to the anode, we can increase the speed of the electrons.

Atomic NumberThe ____________ of the target affects both the number(quantity) and the effective energy (quality) of x-rays.

Inner Shell Electrons Characteristic radiation interacts with the __________ and low energy photons.

Orbital Electron The transition of an __________ from an outer-shell is accompanied by the emission of an x-ray.

Automatic Exposure Control Devices It is adevice that measures the quantity of radiation reaching the image receptor and automatically terminates the exposure when the image receptor has received the required radiation intensity.

a.) Phototimer

b.) Ionization chamber What are the types of AECs?

Phototimer Device The x-ray beam passes through the patient, tabletop, and cassette before it strikes the device. They are calibrated by setting the capacitor-discharge point at a level that produces a satisfactory exposure (density) to the image receptor.

Fluorescent Screen It absorbs x-rays and produces light photons, which are then directed to photomultiplier tube.

Photomultiplier Tube It produces electrons from the light photons received from the fluorescent screen.

Capacitor It receives electrons from the photomultiplier tube and is charged until it reaches a preset value. When the capacitor reaches its preset value, it discharges, triggering an thyratron and opening the relay to terminate the exposure.

Thyratron It regulates the exposure automatically.

Ionization Chamber Device The x-ray beam passes through the patient and tabletop before striking the chamber. The chamber is positioned between the patient and the image receptor. It is made radiolucent so that it will not interfere with the radiographic image.

Backup Timer It is the time the electronic timer is set in case the AEC fails to terminate exposure.

150% Back up times cannot exceed the tube limit and should be set at _______ of the anticipated manual exposure mAs.

600, 2000 Regulations require that AEC's have _____ mAs and _____ mAs safety override.

600 If the AEC fails to terminate the exposure, the secondary safety circuit terminates at ____ mAs for exposures over 50 kVp.

2000 If the AEC fails to terminate the exposure, the secondary safety circuit terminates at ____ mAs for exposures below 50 kVp.

Positioning This must be absolutely accurate.

Density Controls What should not be used to compensate for patient part thickness or kVp changes?

Base Layer The layer farthest from the film and is 1 millimeter thick. It serves as a mechanical support for the active layer.

Reflective Layer It is the layer between the phosphor and the base that is made of a shiny substance such as magnesium oxide or titanium dioxide.

Calcium Tungstate It is an active substance of most phosphor screens before1980's and is embedded in a polymer matrix and slower of the two.

Rare Earth Composed of gadolinium, lanthanum, and yttrium and is newer and faster screens.

Protective Coating The layer of the radiographic screen closest to the radiographic film. It helps to eliminate the buildup of static electricity.

Luminescence It is the emission of light as a direct result of some outside excitation or stimulation.

Fluorescence It occurs when visible light is emitted only when the phosphor is stimulated.

Phosphorescence It occurs if the phosphor continues to emit light after stimulation.

Spatial Resolution The ability to accurately image an object by the use of intensifying-screens.

Film Screen Contact This is one of the most common screen resolution problems is caused by poor contact.

Image Noise It appears on a radiograph as a speckled background. It occurs most often when fast screens and high kVp techniques are used.

Quantum Mottle It is caused by an insufficient quantity of photons striking the intensifying screen.

Quality Control A comprehensive set of activities designed to monitor and maintain systems or equipment that produce a product.

1.) Performed safely

2.) Appropriate for the patient

3.) Performed efficiently

4.)Producing high-quality images Quality Control is performed to ensure that radiologic procedures are?

1.) Acceptance testing

2.) Routine maintenance

3.) Error maintenance The major categories of QC testing include?

Acceptance Testing Performed on newly installed or majorly repaired equipment . It is used to determine whether the equipment is performing within the vendor's specifications and as promised.

Routine Maintenance Performed to ensure that the equipment is performing as expected.

Error Maintenance Corrective actions are performed for errors that occur in equipment performance.

American College of Radiology The organization that requires compliance with standards of practice to ensure quality in any imaging system. Provides recommendations on system tests that must be performed by service personnel (venders, manufacturers) and/or radiologic technologists, and radiation physicists.

Federal Quality Control Standards These are uniform for all manufacturers have yet to be implemented because CR and DR systems are relatively new.

1.) Technologist

2.) Service personnel

3.) Radiation or Medical Physicist Common computed radiography quality control activities, schedules, and responsibilities for?

1.) Cleanliness of cassettes/receptors

2.) Cassette integrity

3.) Ensure imaging plates have been completely erased

4.) Verify digital interfaces and network transmission

5.) Check laser printer functionality, cleanliness, paper, ink, and artifacts produced by dirt or fingerprintsWhat are the daily responsiblities of technologists?

1.) Verify monitor calibration (CRT only)

2.) Clean CRT screen, keyboard, and mouse

3.) Clean and inspect receptors

4.) Follow any manufacturer recommended QC tests

5.) Inspect CR reader What are the weekly responsiblities of technologists?

1.) Perform reject/repeat analysis survey

2.) QC out of standard images

3.) Inspect and clean all image plates (IPs) What are the monthly responsiblities of technologists?

1.) Testing to establish accuracy and reproducibility

2.) Phosphor accuracy testing

3.) Image processing parameters

4.) Tests the system for correct positioning and processing

5.) Screen erasure

6.) Spatial Frequency response testing What are the responsibilities of Service Personnel?

1.) Perform acceptance testing of new equipment

2.) Reviews departmental images

3.) Reestablish baseline values

4.) Check exposure indicator's accuracy with calibrated ion chamber

5.) Determines exposure trends

6.) Analyze repeat rates

7.) Reviews QC records

8.) Analyzes service history of routine maintenance and repairs What are the responsibilities of the Radiation or Medical Physicist?

Repeat Analysis Program It serves to catalog rejected images and determine the nature of the repeat so that repeat images can be minimized or eliminated in the future. It provides important data about equipment and accessory performance, departmental procedures, and the skill level of the technical staff.

4, 6 Department repeat rates should not exceed __ - __%.

Digital Radiography It is hard-wired to the imaging processing system and is cassette-less. It directly converts incoming x-ray photons to an electrical digital signal. It is more efficient in time, space, and personnel than screen film radiography.

Flat Panel or Flat Field Detectors It describes both the indirect amorphous silicon and the direct amorphous selenium plates that are being used in digital radiography.

Detector and Reader They are a permanent part of a table or wall unit.

1.) Direct acquisition systems

Without scintillator

2.) Indirect acquisition systems

With scintillatorWhat are the types of Digital Radiography?

Direct Digital Radiography The X-ray photons are absorbed by the coating material and immediately converted into an electrical signal.

1.) Direct Conversion

2.) Direct Acquisition

3.) Direct Selenium Flat Panel Imaging Systems Direct Digital Radiography is also called?

Amorphous Selenium (a-Se) / TFT(thin-film transistor) It is a post-sensitive array made up of small (100-200 µm) pixels.

Indirect Digital Radiography It is also called Indirect Conversion, or Indirect Acquisition or Indirect Silicon Flat Panel Imaging Plate systems.

Amorphous Silicon (a-Si:H) TFT It cannot directly convert x-rays into an electric charge, but works a light detector to capture fluorescent light.

Cesium Iodide (CsI) TFT A scintillator for Amorphous Silicon converts x-rays into visible light.

Scintillators These convert x-rays to visible light.

Thin-Film Transistors (TFT's) It collects the electric charges produced by the silicon as an array or matrix of pixel-size detector elements.

Incandescent It is the white, glowing, or luminous with intense heat.

Thermionic Emission The emission of electrons from a heated surface.

Filament Current The low-voltage current supplied to the cathode filament heating it up to incandescence causing thermionic emission.

Thermions The electrically charged particles emitted by an incandescent substance.

a.) Force field of the nucleus. (Brems)

b.) An inner shell electron. (Characteristic) According to the basic principles of x-ray production the incident electrons either interact with?

a.) Source and focusing of electrons.

b.) High voltage to produce high speed electrons.

c.) Appropriate target material to stop high speed electrons.

d.) Vacuum What are the conditions required for the production of x-rays in a hot cathode tube?

Strong electric field or Potential difference generated. This causes the space charge electrons to rush from the cathode to the anode.

One-Half The speed of the electrons approaches _______ the speed of light.

Gas The removal of the air permits the electrons to flow from the cathode to the anode without encountering _______ atoms.

Glass Envelope Its primary function is to maintain the vacuum between the cathode and the anode.For the sole function of the removal of air.

Fixer and Wash Water The used _____ contain silver in some form, which is a toxic heavy metal and therefore subject to strict pollution guidelines by the EPA and many state regulations.

Silver Recovery System A ___ is required for most hospitals to remove silver from used processing solutions to meet the requirements of these laws

27 Resource Conservation and Recovery Act of 1987 requires a permit to dump more than __ gallons of waste per month in public sewers.

Metallic Replacement Operates by having the fixer drain into the top of a plastic bucket, filter through the steel wool or screen, and overflow through a tube connected to the bottom of the container. Works by using iron inside the canister to react chemically with the acid and silver ions in the fixer through ion exchange.

Electrolytic Silver Recovery Uses an electric current to reclaim silver by an anode and a cathode that attracts the (+) charged silver ions in fixer to the negative-charged stainless steel drum or disk-shaped cathode.

Terminal Electrolytic System Connected to the fixer overflow line from the processor replenishment system. Once this unit recovers the silver, the used fixer is flushed down the drain.

1.) More efficient than metallic replacement without problems of rusting or drain stopping

2.) Silver recovered is in the form of silver flake, which is 92%-98% pure, as opposed to sludge in a metallic replacement system, which is only 30%-50% pure

3.) System produces no new pollutants

4.) System is reusable because cathode can be cleaned and reused What are the advantages of Electrolytic Silver Recovery?

1.) Higher capital cost for the equipment

2.) Special electrical or plumbing connections may be required in the processing area

3.) Periodic monitoring and servicing are required

4.) Operating cost exists because of the electricity consumed during operation What are the disadvantages of Electrolytic Silver Recovery?

95 If the solution temperature exceeds __°F, the efficiency of the system decreases because of the increased kinetic energy of the silver ions.

Excessive Weight On electrolytic units, the ______ of silver on the cathode puts stress on the drive motor used for agitation, shortening its life span.

X-Ray Photons They deposit energy within the crystal lattice of the silver halide crystals.

Light Photons It comes from the intensifying screens that deposit visible light energy in the film's emulsion through photoelectric interaction with atoms of the silver halide crystal.

Cubic Lattice The "Active" ingredient of the radiographic emulsion is called a?

Photoelectric If x-ray is totally absorbed, its interaction is?

Compton If x-ray is partially absorbed, its interaction is?

Three At least __ silver atoms must be deposited for a visible clump of metallic silver to be formed by chemical development of the image.

Black Metallic Silver Primary purpose of radiographic processing is to deposit enough _____ at the sensitivity centers (latent image sites) to permit a permanent visible image to form.

Developing Stage Principle action is to change the silver ions of exposed crystals into metallic silver.

Developer The ____ provides electrons to the sensitivity center of the crystal to change the silver ions to silver.

1.) Immersion Time

2.) Solution Temperature

3.) Chemical Activity The action of the developer is controlled by the?

Fixing Stage This step is accomplished by using a clearing agent, usually ammonium thiosulfate, which bonds with unexposed silver halides and removes them from the emulsion.

Radiographic Contrast The difference between adjacent densities ranging between clear white through various shades of gray to black.

High Contrast When the differences between adjacent densities are great the image is described as?

1.) Few shades of gray

2.) Increased contrast

3.) Low kVp

4.) Short dynamic range/window width What are the characteristics of high contrast?

Low Contrast When the differences between adjacent densities are minimal the image is described as?

1.) Many shades of gray

2.) Decreased contrast

3.) High kVp

4.) Large dynamic range/window width What are the characteristics of low contrast?

Image Receptor Contrast It is inherent in the intensifying screen-film combination and influenced by the processing of the film.

Standardized Film Processing It is absolutely essential for consistent film contrast and good radiographic quality.

Contrast It is determined by the size, shape, and x-ray attenuating characteristics of the anatomy that is being examined and the energy of the x-ray beam (kVp).

1.) Patient Thickness

2.) Tissue Mass Density

3.) Effective Atomic Number

4.) Object Shape

5.) kVp What are the subject contrast factors?

Contrast Media Subject contrast can be enhanced by the use of?

DICOM A global information technology standard that allows network communication between modality and PACS. System of computer software standards that permit a wide range of digital imaging programs to understand one another.

Radiology Information System (RIS) Information system used in the Radiology department for ordering examinations and reporting results. Sends patient information to be connected to PACS, allowing patient data and images to be connected within the systems.

Hospital Information System A computerized database used to manage the administrative, financial and clinical aspects of a hospital.

Film Digitizer Works similarly to computer scanner by scanning hardcopy films or images and converting to digital format.

Display Workstations Any computer that a health care worker uses to review a digital image and is used inside and outside radiology.

Off-site Storage It is used to ensure data integrity if a catastrophic event were to occur that could destroy data.

Part Selection Selecting the proper body part and position is important for proper conversion to take place, If improper part and/or position selected, the computer will misinterpret the image.

High Resolution Imaging Plates Most often used for extremities, mammography and other exams requiring increased detail and should be marked on the outside to indicate type of IR.

1.) Part size

2.) kVp desired

3.) Scatter cleanup desired

4.) Grid frequency Grid use in CR occurs more often due to the sensitivity of the IP to scatter. The grid selection will depend on what factors?

Focus _________ grids consist of lead strips angled to coincide with the divergence of the x-ray beam and must be used within a specific distance using a precisely centered beam.

Angstrom It is the unit of measure for wavelength. Also a unit of length equal to 10^(-10), or one ten-billionth of a meter.

0.1 - 0.5 The wavelength of diagnostic X-rays is equal to _______ Angstrom?

Electromagnetic Spectrum It is a continuum of electromagnetic energy.

Frequency The number of complete oscillations per second of an electromagnetic wave.

Photon It is the smallest quantity of any type of electromagnetic radiation.

Quantum It is a small bundle of photon energy.

Wavelength It is the distance between any two successive similar points on a wave. It is the length of one cycle.

Electromagnetic Radiation These are the wavelike fluctuations of electric and magnetic fields set up in space by oscillating (vibrating) electrons.

Attenuate It is to lessen the amount, force, magnitude, or value, it is the reduction in radiation intensity as a result of beam absorption and scattering.

Density It is the degree of blackening of a radiograph resulting from radiation exposure and processing and one of the two photographic properties that comprise visibility of detail.

Clear The ______________ area of the radiograph represents low optical density.

Black The ______________ area represents high optical density.

Remnant Radiation It is the radiation that exits the anatomic part and exposes the radiographic screens placed in the protective radiographic cassette.

Exit Radiation Remnant radiation is also known as?

1.) White light

2.) Ultraviolet light

3.) Infrared

4.) Microwaves

5.) Radiowaves

6.) Other similar types of radiant energy X-ray beams consist of a group of rays that are related to?

1 - 50 The energy of X-ray photons ranges from __ keV to __ MeV and higher.

-9 , -12 The associated wavelength is approximately 10^__ to 10^___ m.

18 , 21 The frequency of X-ray photons varies from approximately 10^_____ to 10^_____ Hz.

Highly A property of X-ray is it being _____________ penetrating.

Neutral X-ray is considered to be electrically ____________.

Polyenergetic X-rays could be _____________ or heterogeneous.

StraightX-rays travel ordinarily in _____________ lines.

Heat X-rays liberate a minute amount of ____________ on passing through matter.

3 x 10^8 m/s or 186,000 miles/s X-rays travel only at the speed of light which is equal to?

Fluorescence X-rays cause _________ of certain crystals.

1.) Visible light

2.) Radiofrequency

3.) X-radiation What are the regions of importance to radiography?

c = fλ / c = vλ What is the formula for velocity?

Constant The velocity of all electromagnetic radiation is __________.

Speed of Light In the formula c = fλ, what does c stand for besides velocity?

Wavelength λ is the greek symbol for lambda. In the formula c=fλ, it represents what?

Planck's Constant The constant of proportionality is also known as?

4.15x10^15 eV-s The numerical value of Planck's Constant is equal to?

h Planck's Constant is represented by the symbol?

E = h x f The formula for the relationship of energy and frequency is?

Hz What is the unit of frequency?

I₁ = ( d₂)^2

------ ---------

I₂ ( d₁)^2 What is the formula representation of the Inverse Square Law?

Filament The part of the cathode that emits electrons resulting in a tube current.

Focusing Cup The metal shroud surrounding the filament. It is usually made of molybdenum or nickel.

Space Charge The electron cloud near the filament.

Target The region of the anode struck by electrons emitted by the filament.

Thoriated Tungsten Material The filament or cathode is usually made up of? It promotes higher promotes higher thermionic emission.

Dual Focus X-Ray Tube The smaller of the two is used when image detail is important. The larger filament would be used when high heat exposures are needed. What does this refer to?

Thermionic Emission The process that gives off electrons used in the production of X-rays. A low voltage high filament current is applied through the wires to heat the filament and is about 10 volts and 3 to 5 amperes.

Electrostatic Repulsion The electron beam formed by negatively-charged electrons from the cathode tends to spread out due to?

Negatively - Charged The focusing cup is ________________ to condense the electron beam to a small area in the anode hence reduce the spread of the electron stream striking the anode.

Copper It is a common reddish metallic element that is ductile and malleable and one of the best conductor of heat and electricity.

Stator It is a stationary coil windings located in the protective housing but outside the X-ray tube glass envelope. It is also a part of the electromagnetic induction motor.

Tungsten It is a metal element that is the principal component of the cathode and anode.

Effective Focal Spot (EFS) It is also known as the effective target area, the focal spot projected onto the patient and the image receptor.

Focal Spot (FS) It is also known as the actual focal spot. The region of anode target where electrons interact to produce X-rays and this is the surface from which X-rays are actually produced. It is seen from the cathode end.

Smaller The effective focal spot size is much ____________ than the actual focal spot size.

Anode Heel Effect It is the absorption of X-rays in the heel of the target, resulting in reduced X-ray intensity to the anode side of the central axis. It also states that the radiation intensity on the cathode side of X-ray field is higher than that of the anode side. This concept is useful in radiographing anatomic structures of different thicknesses or densities.

Actual Focal Spot Size The area on the anode target that is exposed to electrons from the tube current.

Line Focus Principle It is a design in the x-ray tube targets that allow a large area for heating while maintaining a small focal spot. By angling the target towards the film or the patient, the projected image is smaller and sharper than the actual image.

Heat It is the greatest limiting factor in x-ray production.

Induction Motor This allows the anode to rotate inside a glass envelope with no mechanical connection to the outside. It is driven by an electromagnetic induction motor.

Stator Assembly It is located outside the glass envelope and it consists a series of electromagnets or stator windings equally spaced around the neck of the tube.

Rotor Assembly It is located inside the glass envelope and is a shaft made of bars of copper and soft iron fabricated into one mass. It is the only part that rotates during the X-ray production process.

Anode Stem or Neck It is made of molybdenum because of its strength, high melting point and poor thermal conductivity helps insulate the induction motor from anode heat.

a.) It acts as an electrical conductor.

b.) Provides mechanical support for the target.

c.) It acts as a good thermal conductor. What are the purposes of anode components?

Stationary Anode An anode component in which the target consists of tungsten-alloy metal embedded in a copper anode.

Copper Anode It is known to be a better conductor of heat than tungsten because it carries the heat away from the target more rapidly thereby protecting it from overheating.

Rotating Anode It is a rotating disk or target in where the disc is a graphite disc with tungsten alloyed with rhenium focal track at its periphery.

a.) During exposure the anode rotates rapidly while being bombarded by the electron stream from the cathode filament.

b.) Ordinarily rated between 3000-3600 rpm for single phase units.

c.) More likely to be 3000 rpm due to rotor slippage.

d.) The higher the speed of rotation the better the heat storage capacity of the rotating anode. What are the functions of a rotating anode?

Fine Radiographic Definition Rotating anode tubes usually have two filament sizes to provide 1 and 2 mm focal spots. The smaller focal spot is used to obtain? This has made superb recorded detail in radiography possible.

Shorter Exposure Time Rotating anode tubes usually have two filament sizes to provide 1 and 2 mm focal spots. The larger focal spot can tolerate heavier loading in? It is to minimize motion in special radiographic procedures.

Focal Track In a rotating anode the X-ray beam and majority of the heat is concentrated and spread over a large area called the? It is located on the beveled face of the anode.

Molybdenum or Rhodium Targets Mammography uses what kind of targets? These targets have low atomic numbers and low K characteristic x-ray energy.

T.A. = L x W What is the formula for the target area of a stationary anode?

T.A. = L x 2πr What is the formula for the target area of a rotating anode?

a.) Provides a larger area for heat loading.

b.) Enables usage of smaller effective focal spot for better radiographic detail and a larger actual focal track area or spot. What are the advantages of x-ray line focus principle?

Three Phase Power It is the multiple voltage waveforms that are superimposed on one another, resulting in a waveform that maintains a nearly constant high voltage.

Three Phase, Six Pulse A three phase generator which has a ripple of 13-25%. The voltagenever drops below 75-87% and has 35% more average energy photons than single phase generators.

Three Phase, Twelve Pulse A three phase generator which has a ripple of 4-10%. The voltagenever drops below 90-96% and has 40% more average energy photons than single phase generators.

Motor Principle The result of the interaction of the magnetic fields when an electric current is sent along a conductor that is residing in a magnetic field.

Galvanometer This is a basic device for the measurement of current and voltage. It consists of a coil of fine copper wire suspended between the poles of a horseshoe magnet.

Ammeter This device measures the quantity of electricity flow per second. It is connected directly into the circuit, which is in series and reads the same no matter where it is placed in a series circuit.

Voltmeter This device measures in volts the differences of potential between any two points in a circuit and is always connected in parallel.

Ground A protective device that is grounded to protect the X-ray specialist and patient from electrical shock. Most electric sockets today are wired with three instead of two connections, the principal two are for the current carrying double wire and third contact is connected directly to earth.

Fuses An equipment protection that prevents prevent overloading in circuits. It is connected in series along the supply line and constructed with a metal tab that will melt when dangerously heated; thus breaking the circuit. It is not reusable it must be replaced when blown.

Circuit Breakers An equipment protection that is constructed to permit the breaking of the circuit before a dangerous temperature is reached. They simply pop open and can be reset once the cause of the problem has been located and removed from the circuit.

Ground Fault Circuit Interrupter A device that protects both the equipment and people using an equipment. It replaces ordinary wall outlet, protects against electrical shock caused by electricity passing through your body to ground. Inexpensive and should be tested monthly.

Choke Coil It is an electromagnetic device operating on the principle of self-induction; requires alternating current.

Rheostat This device permits a variable contact to slide along a series circuit of resistant coils. It functions in the same manner when used as voltage regulating device.

Potentiometer It is another known name of the Rheostat.

Autotransformer It is also known as a variable transformer. It is used in radiographic units to regulate the voltage available to the primary side of the high voltage transformer .

Autotransformer Law The law that talks about the relationship of the voltage output to voltage input in an autotransformer.

Vs/Vp = PT The formula for the number of tapped turns or primary turns.

Main Circuit This is the portion of the x-ray circuit that modifies the incoming power to produce x-rays. This circuit must boost the voltage to the range necessary to produce x-rays and to permit the radiographer to adjust the amperage, voltage, and length of exposure.

Primary Circuit ( Low Voltage Side)

Secondary Circuit (High Voltage Side) The two divisions of the main circuit in an x-ray circuit.

Kilovoltmeter It indicates the desired kV and placed across the output terminal of the autotransformer, and actually reads voltage, not kilovoltage. It indicates kVp on the scale because of the known turns ratio of the high voltage step-up transformer.

Line Voltage Monitor It is connected in parallel across portion of the primary side of the autotransformer. It detects fluctuations in line voltage due to variations in power distribution and power consumption.

Line Voltage Compensator It permits adjustment of the line voltage to the correct value. It varies the number of turns on the primary side of the autotransformer until the compensator meter needle indicates that the correct line voltage has been restored; only then will the correct kV be obtained.

Timer and X-Ray Exposure Switches These switches control the current to the primary coil of the transformer, serving to complete the x-ray exposure.

Secondary Circuit This includes the secondary coil of the high voltage transformer and all of the devices to which it is connected electrically.

Filament Circuit This modifies the incoming line power to produce the thermionic emission from the filament wire of the x-ray tube by a sequence of devices.

200 to 240 Electricity is usually supplied to buildings in the United States by 60Hz AC with a nominal rms of ___ to ___ volts.

Filament Control DeviceIt is also known as the mA selector.

Filament Stabilizer This corrects for the instantaneous fluctuations in line voltage that may be caused by momentary demand elsewhere on the line.

Filament Ammeter This measures filament current, hence the amount of heat developed in the filament.

Space Charge Compensator This automatically lowers filament current as kV is increased or vice versa maintaining the tube current at a nearly constant rate and enables the technologist to change kV without producing appreciable effect on mA.

kVp Selector

mA Selector

Exposure Time Selector

Rotor Switch

Exposure Switch Controls and meters located on the X-Ray Control Panel Console.

Timer Circuit This is separate from the other main circuits of the x-ray machine. It consists of mechanical or electronic devices whose action is to "make" and "break" the high voltage across the x-ray tube.

Synchronous Timer This uses a special type of electric motor known as the synchronous motor, which is a precision device designed to drive a shaft at precisely 60 revolutions per second. It cannot be used for serial exposures because they must be reset after each exposure, which requires too much time.

Electronic Timer This is the most sophisticated and most accurate of the x-ray timers. They allow a wide range of time intervals to be selected and are accurate to intervals as small as 1 millisecond and most radiographic equipment today contain it.

mAs Timer It is a special kind of electronic timer, which monitors the product of mA and time and terminates the exposure when the desired mAs is attained.

Main Switch This part of the primary circuit potentially protects the equipment and reduces fire hazard.

Phototimers It is often used to refer to all automatic exposure controls and uses a thyratron tube to regulate exposure automatically.

Photomultiplier Tube This has the ability to produce a current that charges a capacitor.

Ion Chamber The type of automatic exposure control employed by most manufacturers incorporate a flat, parallel plate ionization chamber between the patient and the film.

.05 Seconds The minimum reaction time of old phototimers.

.001 Seconds The minimum reaction time of modern ionization timers.

US Public Law 90-062 Which law mandates that generators must terminate the exposures at 600 mAs for exposures above 50 kVp and 2000 mAs for exposures below 50 kVp?

150% Backup times cannot exceed the tube limit and should be set at ______% of the anticipated manual exposure mAs.

Field / Pickup Selection These devices located near the x-ray film samples the radiation during exposure and produces an electrical signal proportional to the intensity of the radiation.

Density Control It sets either small, medium or large settings according patient's size.

Filament Transformer It is a step down transformer. The voltage supplied to this transformer is higher than the voltage supplied to the filament.

High Voltage Transformer A step up transformer that increases the primary voltage to provide the high voltage required to operate the x-ray tube, the step up ratio being between 500:1 or 1000:1. It is found in the secondary circuit.

X-Ray Tube This is the last component of the filament circuit.

Low Voltage Side All of the radiographer-operated controls are located on the _______________ of the circuit to protect the operator from high voltage shock hazards.

Automatic Exposure Controls What does AEC stand for?

Minimum Reaction Time All AEC have a _____________ which is determined by the length of time necessary for the AEC to respond to the radiation and for the generator to terminate the exposure.

Manual Backup Time All AEC equipped units permit a ____________ to be set in cases where AEC is improperly set.

Milliammeter Measures mA in the x-ray tube. Connected at the center of the secondary winding of the high voltage step up transformer to ensure safety. The secondary voltage is alternating at 60 Hz such that the center winding is always zero.

Tube Current It is is measured in milliamperes by the milliammeter placed on the high voltage circuit, while an ammeter placed on the low voltage circuit measures the filament current.

Light Photons It comes from the intensifying screens that deposit visible light energy in the film's emulsion through photoelectric interaction with atoms of the silver halide crystal.

Black Metallic Silver Primary purpose of radiographic processing is to deposit enough _____ at the sensitivity centers (latent image sites) to permit a permanent visible image to form.

Image Analysis Method The process of evaluating the quality of a particular radiograph to determine whether it is of sufficient radiographic quality.

Spatial Resolution The ability to image small objects that have high subject contrast, such as bone-soft tissue interface, a breast micro-calcification, or a calcified lung nodule.

Contrast Resolution Ability to distinguish anatomic structures having similar subject contrast.

Radiographic Noise It is the random fluctuation in the optical density of the image.

1.) Film graininess

2.) Structure mottle

3.) Quantum mottle

4.) Scatter radiation What are the four components of noise?

Film Graininess Refers to the distribution in size and space of the silver halide grains in the film emulsion. Inherent in the IR.

Structure Mottle Refers to the phosphor of the radiographic intensifying screen. Inherent in the IR.

Quantum Mottle Refers to the random nature by which x-rays interact with the IR and is under the control of the radiographer and is the principal contributor to radiographic noise.

Artifacts It is any irregularity on an image that is not caused by the proper shadowing of tissue by the primary beam. They are undesirable optical densities and must be prevented.

Speed It is not apparent on the radiographic image and influences resolution and noise.

1.) Fast image receptors have high noise and low spatial resolution and contrast resolution

2.) High spatial resolution and contrast resolution require low noise and slow image receptors

3.) Low noise accompanies slow image receptors with high spatial resolution and contrast resolutionWhat are the radiographic quality rules?

High Quality Radiograph They are required for accurate diagnosis.

1.) Film factors

2.) Geometric factors

3.) Subject factors To achieve high quality radiographs, interrelated categories of radiographic quality are required. They are?

Film Factors The relationship between the film and the intensity of the exposure of the film and the blackness after processing is known as "sensitometry" and is essential for maintaining adequate quality control.

1.) Magnification

2.) Distortion

3.) Focal-spot blur What are the principal geometric factors affect radiographic quality?

Subject Factors These factors involve the patient and the selection of radiographic technique that compensates for the patient's size, shape, and tissue composition.

1.) Subject contrast

2.) Patient thickness

3.) Tissue mass density

4.) Effective atomic number

5.) Object shape

6.) Kilovoltage peak (kVp) What are the kinds of subject factors?

Exposure Factors They are the tools that radiographers use to create high-quality radiographs.

1.) kVp

2.) Current (mA)

3.) Time (s)

4.) SID The prime exposure factors are?

Patient Factors One of the most difficult tasks for a radiographer involves evaluation of the patient size, shape and physical condition which greatly influences the radiographic technique.

Body Habitus The size and shape of a patient is called?

Sthenic Patient The strong, active, the average patient.

Hyposthenic Patient Patient that is thin but healthy appearing.

Hypersthenic Patient Patient that has a big frame, usually overweight.

Asthenic Patient Patient that is small, frail, sometimes emaciated and often elderly.

Body Thickness The thicker the _____ of the patient the more x-radiation is required to penetrate the patient and expose the IR.

CalipersRadiographers should always use _____ to measure body thickness or the part being examined.

Body Composition The anatomical part may have the same thickness but require a totally different radiographic technique depending on the tissues involved.

Pathology Some ______ is destructive, causing the tissue to be radiolucent and can constructively increase mass density causing the tissue to be radiopaque.

Image Quality Factors They are considered the "language" of radiography and provide a means for the radiographer to produce, review and evaluate radiographs. It refers to the characteristics of the radiographic image and includes optical density, contrast, image detail and distortion.

Radiographic Technique Charts They are tables that provide a means for determining the specific technical factors to be used for a given radiographic examination.

1.) Variable kVp charts

2.) Fixed kVp chart

3.) High voltage kVp chart

4.) Automatic exposure charts What are the types of technique charts?

Variable kVp Charts Uses fixed mA value and a kVp that varies according to the thickness of the anatomical part being examined.

Fixed kVp Charts Used most often and the kVp selected is the optimum required for penetration of the anatomical part.

High Voltage kVp ChartsUsed when the kVp selected is greater than 100 kVp.

Automatic Exposure Charts It is needed for selection of the peak kVp, optical density, collimation and radiation dose-image quality ratio.

Medical Physicist Before preparation of the radiographic technique chart begins, the imaging equipment must be calibrated by a ___?

2.5 mm Al What is the prescribed standard for total filtration?

Artifacts Any irregularity on an image that is not caused by the proper shadowing of tissue by the primary beam.

1.) Storage and handling artifacts

2.) Exposure artifacts

3.) Processing artifacts Three classifications of artifacts?

Roller Marks Guide shoe marks occur when the guide shoes are sprung or incorrectly positioned and are found on the leading or the trailing edges of the film parallel to the direction of film travel through the processor.

Dirty Rollers The rollers that can cause "emulsion pick-off" and or "gelatin buildup, which results in "sludge" deposits on the film.

Chemical Fog Usually results from incorrect or inadequate processing chemistry or processing technique.

Wet-Pressure Sensitization A common artifact that is produced in the developing tank. Irregular or dirty rollers cause pressure during development and produces small circular patterns of OD.

Image Fog Artifact caused by the temperature or the humidity being too high.

Pressure Marks What can occur if the film is stacked too high?

Light or Radiation Fog White-light leaks in the darkroom or within the film cassette causes streak-like artifacts of increased OD.

68 Films should be stored in room temperature of __ degree Fahrenheit.

30 - 60 Humidity in film storage rooms should be maintained at __ - __ %.

Hypo Retention A yellow-brown stain appears on the film after a long storage period indicating a problem with _____ from the fixer.

Static Artifacts Cause by a buildup of electrons in the emulsion and is most noticeable during winter or periods of extremely low humidity.

Crown Static Static artifact that resembles a crown.

Tree Static The tree or bush-like with fingerlike processes emanating outward from point of discharge.

Smudge Static It assumes characteristic of black smudges.

Electrostatic Cleaner Solution Clean intensifying screens regularly with commercial _____ recommended by the manufacturer.

Kink Marks It can be caused by incorrect or rough handling during loading and unloading film cassettes or storage either before or after processing.

Crescent / Crinkle Marks Kink marks are also known as?

Semi-Circular Appearance of kink marks is _____ in shape.

Exposure Artifacts Artifacts associated with how the radiographer conducts the examination.

1.) Incorrect screen-film match

2.) Poor screen-film contact

3.) Warped cassette

4.) Incorrect positioning of the grid

5.) Patient preparation Examples of exposure artifacts?

Screen-Film Match Radiographic film and intensifying screens are designed to complement each other and to produce the highest quality image with the lowest patient radiation exposure.

Screen-Film Contact Intensifying screens are designed to so that each sheet of film can be sandwiched tightly between them.

Warped Cassette What can cause a loss of contact between the film and intensifying screens causing a diverging of the light photons from the screens causing a loss of detail and contrast?

Correct Grid Positioning What is essential to prevent the undesirable absorption of primary radiation known as "grid cut-off"?

Patient Preparation What is essential for producing artifact-free images?

Automatic Processing Artifacts What artifacts are caused by the transport system of the processor, and are of the pressure-type that sensitize the emulsion and appear as higher optical density?

Guide Shoe Marks What can occur when the guide shoes are sprung or incorrectly positioned. The marks are found on the leading or the trailing edges of the film they are straight and run parallel in the direction of film travel through the processor?

Manual Processing What takes approximately one hour to prepare a completely dry and ready-to-read radiograph?

Support Structure

Protective Housing

Enclosure The external structure of the X-ray tube consists of what parts?

Ceiling System

Floor To Ceiling

C-Arm What are the three types of support system?

Ceiling Support System This is the most common type of support system used. It consists of two perpendicular sets of ceiling mounted rails which allow for both longitudinal and transverse travel. Its telescoping column attaches tube housing to rails. It allows variable SID and has a preferred detent position.

Floor To Ceiling SupportIt is a single column support system with rollers at each end; one attached to ceiling-mounted rail and the other to floor-mounted rail. The x-ray tube slides up and down the column as the column rotates. A variation of this type of support system has the column positioned on a single floor support system with one or two mounting rails.

C-Arm Support It is the most commonly used in angio-interventional systems.

It is ceiling mounted and very flexible. The image receptor is attached to the other end from the x-ray tube.

U-Arm and L-Arm What are the two variations of the C-Arm Support system?

Protective Housing The modern X-ray tubes must be mounted inside a ______________, provides mechanical support for the tube. It's function is to control leakage and scatter radiation and also serves to cushion the X-ray tube from rough handling by operators.

Cast Steel The protective housing is composed of?

Unwanted Photons The protective housing is capable of absorbing most of what?

Lead The protective housing is lined with this for additional absorption and only at the cathode end because of the direction of the photons being emitted from the anode.

Leakage Radiation Any photons that escape from the housing except at the port are called?

100 mR/hr at 1 meter The leakage radiation must not exceed ______________ as per federal standards.

Special Dielectric Oil A _________________ is used to fill the space between the glass envelope and the tube housing for high-voltage isolation and tube cooling. Under no circumstances should anyone be in contact with a tube housing during an exposure.

Glass Envelope It is commonly referred to as the tube and encloses the entire cathode and anode assembly except the stator. It is sealed tight to maintain a high vacuum to increase effciency of the tube's operation therefore producing more x-rays.

Pyrex Glass A glass envelope is made by sculpting different types of heat resistant _____________.

Off-Focus Radiation or Extra Focal Radiation It is composed of photons that were not produced at the focal spot. The focal spot can produce scattered electrons or photons.

Grounded Metal, Ceramic Envelope The x-ray tubes are available with a ______________ and __________________ to absorb off-focus radiation.

Ghosting Off-focus radiation causes _______________ of structures adjacent to the edge of the primary beam. It is not the same as scatter radiation from the patient.

25-30 Off-focus radiation may contribute as much as ______ percent of the total primary beam.

Window Segment It is the point where the primary X-ray beam exits the glass envelope.

Tomography What is the imaging modality that uses motion to bring into focus only the anatomic structure lying in a plane of interest, while structures on either side of that plane are blurred?

Superimposing Tomography avoids ______ structures as in conventional radiography.

Linear Tomography The simplest tomographic examination is?

Synchronous Movement The principle of tomography is based on the _____ of two of the three elements in a tomographic system: x-ray tube, object and image receptor.

Increased Patient Dose What is the principle disadvantage of tomography?

1,000 What is the average mrad for a nephrotomographic exposure?

Tomographic Amplitude (Arc or Angle) This is the total distance the tube travels.

Exposure Amplitude This is the total distance the tube travels during the exposure.

Blur What is the streaking or smearing that results in the loss of nearly all recorded detail of objects outside the focal plane?

Phantoms What do you call false images and are dangerous to the diagnostic process known as "blur edges"? They are produced by complex tomographic motions, circular, blur overlap, and displacement of blur margins.

Fulcrum The pivot point around which the motions of the tube and the image receptor are centered. It determines the focal plane and controls the section level.

Focal Plane It is the region within which the image exhibits satisfactory recorded detail and is controlled by the level of the fulcrum.

Section Thickness It is the width of the focal plane and is controlled by the exposure angle. It occurs in a plane parallel to the image receptor.

48 To avoid excessive shape distortion, the amplitude of the tube does not exceed how many degrees?

a.) Linear

b.) Curvilinear

c.) Elliptical

d.) Figure Eight

e.) Trispiral

f.) Hypocycloidal What are the types of tomographic movements?

Linear Motion It occurs when movement of the tube and image receptor are along a straight line.

Curvilinear Motion It improves on the linear motion by maintaining SID and OID and reducing magnification differences.

Elliptical Motion This eliminates some of the edge phantoms of circular motions.

Figure Eight Motion This movement eliminate most phantoms images, although their total tomographic amplitude is not as great as that of trispiral or hypocycloidal.

Trispiral and Hypcycloidal Motion This movement provides maximum tomographic amplitude, producing the thinnest possible section.

Linear or Unidirectional Tomogram This uses a basic x-ray table with the bucky tray and overhead tube connected by a metal connecting arm.

Panorex Unit The machine used for pantomography. Pantomography is used for curved body parts, most commonly the mandible, and for dental purposes.

Panoramic Tomography It is used to perform slit scan radiography of the curved surfaces of the face and head and uses only the perpendicular photons of the primary beam by using a lead mask to collimate the beam to a narrow slit.

Narrow-Angle Tomography/ZonographyThis is used when localization is necessary because the exact location of a structure is unknown or when a survey is being performed, for example, on a lesion of the lung or on a kidney.

Wide-Angle Tomography This is used when a lesion has been localized or a specific structure has been determined to require a more detailed examination and is useful in the examination of small bone structures, such as the inner ear.

Filtration It is the removal of low-energy x-rays from the useful beam with aluminum or other metal.

Half-Value Layer (HVL) It is the thickness of absorber or homogenous filter that will reduce an x-ray beam to half its original value or intensity.

Quality The penetrability or penetrating power of an x-ray beam.

Hard X-Rays X-rays with high penetrability are termed high-quality or?

Soft X-Rays X-rays with with low penetrability are of low quality and are called?

kVp What controls the scale of contrast on the finished radiograph?

Penetrability What is the ability of the x-ray to pass through structures and tissues?

Kilovoltage and Filtration What are the factors that affect the quality of x-ray?

Kilovoltage It is the primary control of x-ray beam quality and therefore beam penetrability.It also controls the scale of contrast on the finished radiograph.

High kVp What does the acronym HELL refer to?

H ?

E quals

L ow Contrast

L ong Scale

Low kVp What does the acronym LESH refer to?

L ?

E quals

S hort Scale

H igh Contrast

Filter It's function is to shape beam's energy spectrum and selectively attenuate low energy photons.

Aluminum

Copper

Gadolinium

Holmium What are the materials used as X-ray filter?

Aluminum It is efficient in removing low-energy x-rays, readily available, inexpensive and easily shaped into filters.

a.) Results in x-ray beam with higher energy.

b.) Greater penetrability.

c.) Higher beam quality.

d.) Increased in half-value layer. What are the advantages of having filters?

Inherent Filtration This is the filtration that is a result of the composition of the tube and housing.

a.) The thickness of the glass envelope of the tube.

b.) The dielectric oil coolant that surrounds the tube.

c.) The port or glass window of the housing. What are some sources of inherent filtration?

0.5mm-1.00mmGeneral purpose x-ray tubes use _________ aluminum equivalent (Al/Eq).

0.1mm Special purpose tubes, such as those used in mammography have very thin x-ray tube windows and is made of Beryllium, rather than glass and have inherent filtration of approximately ________ aluminum equivalent (Al/Eq).

Added Filtration This is the filtration that is placed between the protective tube housing and the external housing or collimator.

Compensating Filter These are the filters that are used to compensate for differences in subject radiopacity and used to even out widely differing tissue densities.

Wedge Filter A type of compensating filter that is used to radiograph body parts that varies considerably such as the foot.

Trough Filter / Bilateral Wedge Filter A type of compensating filter that is used mainly for chest radiography.

Bow-Tie-Shaped Filters A type of compensating filter that is used in some CT scanners to compensate for the shaped of the head or body.

Cone Filters They are concave or convex shaped, and find application in digital fluoroscopy, where image intensifier tube and receptor are round.

Step-Wedge Filter A filter that is used in some special procedures, where long sections of the anatomy are radiographed with two or three separate films and also used in rapid film changers for translumbar and femoral arteriography and venography.

Aperture Diaphragm A flat sheet of metal, usually lead with a hole cut in the center, and attached to the x-ray tube port. The simple design, low cost, and ease of use are the main advantages.

Cone It has an extension which flares or diverges with the upper diameter smaller than the bottom flared end.

Cylinder It does not flare. It has the same diameter at the bottom of the extension as it has at the top.

Collimators It is the most commonly employed beam restrictor in radiography.

Lead Shutters Collimators consists of sets of ____________ at right angles to one another that move in opposing pairs.

Field center Indicator This is the crosshair that which light projects field center on patient.

Change in mA or mAs It means a change in the amplitude or quantity (exposure rate) of the x-ray emission spectrum at all energies.

Change in kVp A ___________ affects both the amplitude and the position of the x-ray emission spectrum and affects both the quantity and quality of x-rays.

Target Material Increasing target atomic number enhances the efficiency of x-ray production and the energy of characteristic and Bremsstrahlung x-rays.

Radiographic Contrast It is the difference in optical density (OD) between adjacent anatomical structures or the variation in OD on a radiograph.

Gray Scale of Contrast This refers to the range of OD's from the whitest to the blackest part of the radiograph.

kVp

15% Rule

5% Rule

mAs

Intensifying Screens

Collimation

Anti-scatter Grids What are the factors influencing contrast?

15% Rule It is used to change scale of contrast from long to short or vice versa. To change the kVp by 15 % while changing the mAs by one half or double to produce the same OD.

5% RuleA smaller technique compensation for a change in contrast scale. An increase of 5% in kVp may be accompanied by a 30% reduction in mAs to produce the same OD.

Shoulder and Toe Contrast is low on the ____ and ___ regions.

Intensifying Screens This results in shorter scale of contrast compared with non-screen.

Collimation This removes some scatter radiation producing radiographs of shorter scale of contrast.

Radiographic Detail It is Also known as "recorded detail" or "spatial resolution".

Sharpness of Image Detail This refers to the structural lines or borders of tissues in the image and the amount of blur.

a.) Recorded detail

b.) Visibility of image detail: the ability to see detail on the radiograph and is best measured by contrast resolution. Radiographic detail is evaluated by the:

Focal spot (FS) size It is the major controller of image resolution and it controls penumbra. As it's size decreases, the penumbra decreases, thus increasing resolution. The same concept of increase of the SID.

Penumbra It is the imperfect, unsharp shadow surrounding the distinctly sharp area of a shadow called the umbra.

a.) Focal spot (FS) size

b.) Source Image Distance (SID)

c.) Object Image Distance (OID) What are the geometric factors controlling detail?

a.) Detail

b.) Light fog

c.) Radiation fog What are some factors that causes deterioration or obscuring of image?

Motion It fails to permit enough time for a well-defined image to form and affects recorded detail.

a.) Voluntary

b.) Involuntary

c.) Equipment What are the types of motion?

Voluntary It is the motion under the direct control of the patient.

Involuntary It is the motion not under the conscious control of the patient.

Equipment Motion Motion coming from reciprocating grids that can cause vibrations of the cassette, overhead tube suspension system can drift.

a.) Communication

b.) Exposure Time Reduction

c.) Immobilization What are some methods of reducing motion?

Image Distortion It is the misrepresentation of object size and shape on the radiograph. An untrue size or shape of an object.

Magnification It is the only type of size distortion with film/screen radiography since minification is impossible.

Radiographic Distances Size distortion is controlled by the?

Shape Distortion The misrepresentation by unequal magnification of the actual shape of the structure being examined.

Elongation The anatomical part appears bigger than normal due to poor alignment of the IR or the x-ray tube.

Foreshortening The anatomical part appears smaller than normal due to poor alignment of the anatomical part.

a.) Central ray

b.) The anatomical part

c.) Image receptor Misrepresentation can be minimized through proper alignment of the:

Fluoroscopic Capability of the C-Arm Designed to be very maneuverable, with C-arm attached to an L-shaped arm that can be raised and lowered or extended. Most commonly used in the ER or OR.

a.) Raise

b.) Lower

c.) Extend

d.) Rotate

e.) Tilt What are the movement types of the C-Arm?

Magnification Mode It refers to the ability to magnify the image when requested by surgeons. Surgeons normally need to view images from a distance.

Pulse Mode It is used to create a pulsating x-ray beam at timed increments to reduce exposure.

Snapshot or Digital Spot Mode This results in a higher quality computer-enhanced image as compared with a fluoro image.

Film Mode It is used for exposing standard cassettes placed in the optional holder on the image intensifier.

Auto-Manual Exposure Control This allows for manual exposure control by the operator or the use of Automatic Exposure Control (AEC).

Road Mapping Image display wherein a specific fluoro image is held on the screen in combination with continuous fluoro.

Foot Pedal Allows the operator t have hands-free operation of the unit. It has multiple pedals for controlling various functions such as Scout Fluoro, Image Save, Digital Process Fluoro, and Boost/Digital Spot.

Vertical PA Projection Central Ray (CR) A C-Arm movement that minimizes exposure to the neck and facial region. A 30°C-arm tilt will increase the dose by a factor of four.

Horizontal Projection CR A C-Arm movement in which the exposure region on the x-ray tube side of the patient is significantly greater than the region near the intensifier tower.

Vertical AP Projection CR A C-Arm movement that is not recommended because of significant increase in exposure, up to 100 times higher dose to the eyes but it provides surgeon more room for manipulation.

Operative Cholangiogram It is performed during surgery to demonstrate anatomy of the biliary ductal system, drainage into the duodenum, and any residual stones in the biliary ducts.

Laparascopic Cholecystectomy It is a less invasive approach for the removal of diseased gallbladders. The surgeon makes a small opening in the umbilicus and passes an endoscope into the abdominal cavity.

Retrograde Urography The nonfunctional examination of the urinary system with contrast medium is introduced directly retrograde into the pelvicalyceal system.

Hip Fractures Pinning It is used to verify the position and location of guide pins and internal fixator.

Laminectomy The procedure to alleviate pain caused by neural impingement. The C-arm is used to provide fluoroscopic guidance if orthopedic plates and/or screws are used during surgery.

a.) Time

b.) Distance

c.) Shielding What are the cardinal rules of radiation protection?

Audible 5-Minute Timer Federal law requires an ______________, which serves to remind the radiologist or operator of how much exposure time is being used.

Distance This it the most effective means of reducing occupational exposure.

0.25mm Pb/Eq Lead aprons must be at least?

Patient The primary source of exposure to the radiographer and the fluoroscopy operator is the ________.

Rectification It is the process by which alternating current is changed to pulsating direct current. It also permits electrons to flow easily in one direction while offering high resistance to movement in the other direction.

Cathode, Anode The x-ray tubes operates best when receiving direct current meaning it's coming from the ___________ to the __________.

Diode It is an electronic device that contains two electrodes.

Half-Wave Rectification This is the type of rectification that suppresses the opposing half of the incoming AC cycle, specifically the negative half cycle. It is also called the "one-pulse" rectification. The opposing half of the flow is ignored and not utilized. It can be accomplished by using one or two diodes. 60 pulses per 60Hz current.

Full-Wave Rectification This is the type of rectification that converts the opposing half of the AC cycle so that electrons are routed toward the cathode. This is also called "two-pulse" rectification since there are two voltage peaks per cycle. It is accomplished through an ingenious arrangement of four rectifiers in a

bridge circuit. If a single rectifier fails in a full-wave unit, it will act as a half-wave unit going from 120 pulses to 60 pulses per second. 120 pulses per 60Hz current.

Power Output Capability An advantage of a full-wave rectification is that it permits a significant increase in the _______________ of radiographic equipment which results in larger exposures.

Low Energy X-rays, Low kV Range The disadvantage of a full-wave rectification is it using the entire AC wave results in the production of a high percentage of ______________ or ______________.

Low Heat Loading Capacity The principal disadvantage of self-rectification is the _______________ of a X-ray tube.

Diode Rectification A type of rectification that uses solid state diode rectifiers. It is made of semiconductors.

Silicon It is the most commonly used semiconductor.

N-type and P-type Semiconductors are classified into what two types?

N-type Semiconductors These have loosely bound electrons that are relatively free to move about inside the material.

P-type Semiconductors These have electrons traps, spaces where electrons can be found. These positive traps, called holes, can also be viewed as being free to migrate through the material.

P-N Junction This is formed when the n-type and p-type material are combined in where electrons are allowed to flow only in one direction.

Forward Bias The process when the negative terminal of the AC source is connected to the N-end and the positive terminal to the P-end, electrons and holes flow toward each other, reducing the barrier voltage, allowing current to flow across the junction and the external circuit.

Reverse Bias The process when the positive terminal of the AC source is connected to the N-end and the negative terminal to the P-end, electrons and holes move away from each other, increasing the barrier voltage and preventing current across the junction.

Solid Sate Diode This electrical graphic symbol "---‣|---" denotes what?

The arrowhead in the symbol to indicate the direction of conventional electric current.

Radiographic Underexposure During a rectifier failure, when one rectifier fails in a single phase full wave rectified system, it operates as a two-diode rectifier. It produces a drop in the milliammeter reading to about one-half the normal value which then causes ___________________.

Filtration It is the removal of low-energy x-rays from the useful beam with aluminum or other metal.

Half-Value Layer (HVL) It is the thickness of absorber or homogenous filter that will reduce an x-ray beam to half its original value or intensity.

Quality The penetrability or penetrating power of an x-ray beam.

Hard X-Rays X-rays with high penetrability are termed high-quality or?

Soft X-Rays X-rays with with low penetrability are of low quality and are called?

kVp What controls the scale of contrast on the finished radiograph?

Penetrability What is the ability of the x-ray to pass through structures and tissues?

Kilovoltage and Filtration What are the factors that affect the quality of x-ray?

Kilovoltage It is the primary control of x-ray beam quality and therefore beam penetrability.It also controls the scale of contrast on the finished radiograph.

High kVp What does the acronym HELL refer to?

H ?

E quals

L ow Contrast

L ong Scale

Low kVp What does the acronym LESH refer to?

L ?

E quals

S hort Scale

H igh Contrast

Filter It's function is to shape beam's energy spectrum and selectively attenuate low energy photons.

Aluminum

Copper

Gadolinium

Holmium What are the materials used as X-ray filter?

Aluminum It is efficient in removing low-energy x-rays, readily available, inexpensive and easily shaped into filters.

a.) Results in x-ray beam with higher energy.

b.) Greater penetrability.

c.) Higher beam quality.

d.) Increased in half-value layer. What are the advantages of having filters?

Inherent Filtration This is the filtration that is a result of the composition of the tube and housing.

a.) The thickness of the glass envelope of the tube.

b.) The dielectric oil coolant that surrounds the tube.

c.) The port or glass window of the housing. What are some sources of inherent filtration?

0.5mm-1.00mmGeneral purpose x-ray tubes use _________ aluminum equivalent (Al/Eq).

0.1mm Special purpose tubes, such as those used in mammography have very thin x-ray tube windows and is made of Beryllium, rather than glass and have inherent filtration of approximately ________ aluminum equivalent (Al/Eq).

Added Filtration This is the filtration that is placed between the protective tube housing and the external housing or collimator.

Compensating Filter These are the filters that are used to compensate for differences in subject radiopacity and used to even out widely differing tissue densities.

Wedge Filter A type of compensating filter that is used to radiograph body parts that varies considerably such as the foot.

Trough Filter / Bilateral Wedge Filter A type of compensating filter that is used mainly for chest radiography.

Bow-Tie-Shaped Filters A type of compensating filter that is used in some CT scanners to compensate for the shaped of the head or body.

Cone Filters They are concave or convex shaped, and find application in digital fluoroscopy, where image intensifier tube and receptor are round.

Step-Wedge Filter A filter that is used in some special procedures, where long sections of the anatomy are radiographed with two or three separate films and also used in rapid film changers for translumbar and femoral arteriography and venography.

Aperture Diaphragm A flat sheet of metal, usually lead with a hole cut in the center, and attached to the x-ray tube port. The simple design, low cost, and ease of use are the main advantages.

Cone It has an extension which flares or diverges with the upper diameter smaller than the bottom flared end.

Cylinder It does not flare. It has the same diameter at the bottom of the extension as it has at the top.

Collimators It is the most commonly employed beam restrictor in radiography.

Lead Shutters Collimators consists of sets of ____________ at right angles to one another that move in opposing pairs.

Field center Indicator This is the crosshair that which light projects field center on patient.

Change in mA or mAs It means a change in the amplitude or quantity (exposure rate) of the x-ray emission spectrum at all energies.

Change in kVp A ___________ affects both the amplitude and the position of the x-ray emission spectrum and affects both the quantity and quality of x-rays.

Target Material Increasing target atomic number enhances the efficiency of x-ray production and the energy of characteristic and Bremsstrahlung x-rays.

Radiographic Contrast It is the difference in optical density (OD) between adjacent anatomical structures or the variation in OD on a radiograph.

Gray Scale of Contrast This refers to the range of OD's from the whitest to the blackest part of the radiograph.

kVp

15% Rule

5% Rule

mAs

Intensifying Screens

Collimation

Anti-scatter Grids What are the factors influencing contrast?

15% Rule It is used to change scale of contrast from long to short or vice versa. To change the kVp by 15 % while changing the mAs by one half or double to produce the same OD.

5% RuleA smaller technique compensation for a change in contrast scale. An increase of 5% in kVp may be accompanied by a 30% reduction in mAs to produce the same OD.

Shoulder and Toe Contrast is low on the ____ and ___ regions.

Intensifying Screens This results in shorter scale of contrast compared with non-screen.

Collimation This removes some scatter radiation producing radiographs of shorter scale of contrast.

Radiographic Detail It is Also known as "recorded detail" or "spatial resolution".

Sharpness of Image Detail This refers to the structural lines or borders of tissues in the image and the amount of blur.

a.) Recorded detail

b.) Visibility of image detail: the ability to see detail on the radiograph and is best measured by contrast resolution. Radiographic detail is evaluated by the:

Focal spot (FS) size It is the major controller of image resolution and it controls penumbra. As it's size decreases, the penumbra decreases, thus increasing resolution. The same concept of increase of the SID.

Penumbra It is the imperfect, unsharp shadow surrounding the distinctly sharp area of a shadow called the umbra.

a.) Focal spot (FS) size

b.) Source Image Distance (SID)

c.) Object Image Distance (OID) What are the geometric factors controlling detail?

a.) Detail

b.) Light fog

c.) Radiation fog What are some factors that causes deterioration or obscuring of image?

Motion It fails to permit enough time for a well-defined image to form and affects recorded detail.

a.) Voluntary

b.) Involuntary

c.) Equipment What are the types of motion?

Voluntary It is the motion under the direct control of the patient.

Involuntary It is the motion not under the conscious control of the patient.

Equipment Motion Motion coming from reciprocating grids that can cause vibrations of the cassette, overhead tube suspension system can drift.

a.) Communication

b.) Exposure Time Reduction

c.) Immobilization What are some methods of reducing motion?

Image Distortion It is the misrepresentation of object size and shape on the radiograph. An untrue size or shape of an object.

Magnification It is the only type of size distortion with film/screen radiography since minification is impossible.

Radiographic Distances Size distortion is controlled by the?

Shape Distortion The misrepresentation by unequal magnification of the actual shape of the structure being examined.

Elongation The anatomical part appears bigger than normal due to poor alignment of the IR or the x-ray tube.

Foreshortening The anatomical part appears smaller than normal due to poor alignment of the anatomical part.

a.) Central ray

b.) The anatomical part

c.) Image receptor Misrepresentation can be minimized through proper alignment of the:

Digital Fluoroscopy It is conducted in much the same manner as conventional fluoroscopy but with the addition of a computer, multiple monitors, and a more complex operating console.

Pulse-Progressive Fluoroscopy Images from DF are obtained by pulsing the x-ray beam in a manner called ?

Thin Film Transistor (TFT) DF is achieved through the use of a _____ in contact with the image intensifier output anode screen. It is a pixelated unit with a photodiode connected to each pixel element.

Flat Panel Image Receptors (FPIRS) Thin Film Transistor (TFT) is also referred as?

Scintillator A ______ is a material that emits light when exposed to ionizing radiation.

Video Analog to Digital (ADC) A type of acquisition that receives output signal from the image-intensified digital receptor and accepts the continuously varying signal, the analog signal, and digitizes it.

Charged Coupled Device (CCD) It is a semiconducting device capable of storing a charge from light photons and striking a photosensitive surface and has the ability to store freed electrons, thus storing the image in a latent form. It's primary advantage is the extremely fast discharge time.

Direct Selenium A semiconductor with excellent photon detection and spatial resolution and uses a high voltage charge.

Flat Panel Image Display This is rapidly replacing the cathode ray tube used in conventional radiography and fluoroscopy (CRT).

a.) Easier to view and manipulate

b.) Provides better images

c.) Can be readily mounted in angiography and OR rooms What are the advantages of flat panel image display?

Output Signal It is the signal from the image-intensified digital image receptor is transmitted to an Analog-to-Digital Converter (ADC).

a.) Low Dose Rate

b.) Static Images

c.) Spot Images What are some techniques for reducing patient and operator exposure?

Video Camera Tube What is the most commonly used fluoroscopic viewing system?

Video Camera Charged-Coupled Device It is a semiconducting device that stores a charge from light photons striking a photosensitive surface and stores the image in a latent form.

Cathode Ray Tube (CRT)It has a fluorescent phosphor coating on the inside of the front screen and an electron gun with deflecting and focusing electromagnets.

Cine Film Systems What has a cinecamera positioned to intercept images produced by output screen of intensifying screen? It requires about 90% of the image intensity for proper exposure levels and uses both 16 and 35 mm formats.

Cinefluoroscopy Cine film systems is also referred to as?

Video Recorders It requires high resolution cameras, tape and monitor for the significant increase in resolution and works like a home video system.

Cassette-Loaded Spot Films This is positioned between the patient and the image intensifier. It requires a higher patient dose but produces high image quality.

Photospot Camera It is similar to a movie camera but exposes one frame at a time. This receives image from the output phosphor of the image-intensifier tube and therefore requires less patient exposure than cassette-loaded spot films.

70, 105 Photospot camera uses film sizes of ___ - ____ mm.

Electrostatics The study of stationary or resting charges.

Ground A connection made to the earth. Potential is zero.

Electrification The process by which electrons are added or removed from a body.

Methods of Electrification a.) Friction

b.) Contact

c.) Induction

Friction Transfer of electrons from one object to another by rubbing. Simplest and most fundamental means of electrification.

Negatively Charged The object gaining electrons become?

Positively Charged The object losing electrons become?

Contact Occurs when two objects touch, permitting electrons to move from one to the other. A simple equalization of charges with both objects having similar charges after contact.

Induction A process of electrical fields acting on one another without contact. Every charged body is surrounded by a force field called an electric field.

Metallic Conductors Induction utilizes what?

Laws of Electrostatics a.) Repulsion - Attraction

b.) The Inverse Square Law

c.) Distribution

d.) Movement

e.) Concentration

Repulsion - Attraction Like charges repel, Unlike charges attract.

Inverse Square Law The force between two charges is directly proportional to the product of their magnitude, and inversely proportional to the square of the distance between them.

Distribution Charges reside on the external surfaces of conductors. The result of the repulsion-attraction law as electrons, all with negative charges attempt to repel each other as much as possible.

Movement Only negative charges move along solid conductors. The positive charges are actually charged atoms which do not drift in solid conductors.

Concentration The greatest concentration of charge is on the surface where the curvature is greatest.Electric charges tend to concentrate in the region of sharpest curvature.

Static DischargeWhen two oppositely charged objects are in close proximity, the electrons often jump the gap in the form of a stable discharge.

Light Photons and Audible Sound Static discharge releases excess energy in the form of?

Automatic Exposure Control Devices It is adevice that measures the quantity of radiation reaching the image receptor and automatically terminates the exposure when the image receptor has received the required radiation intensity.

a.) Phototimer

b.) Ionization chamber What are the types of AECs?

Phototimer Device The x-ray beam passes through the patient, tabletop, and cassette before it strikes the device. They are calibrated by setting the capacitor-discharge point at a level that produces a satisfactory exposure (density) to the image receptor.

Fluorescent Screen It absorbs x-rays and produces light photons, which are then directed to photomultiplier tube.

Photomultiplier Tube It produces electrons from the light photons received from the fluorescent screen.

Capacitor It receives electrons from the photomultiplier tube and is charged until it reaches a preset value. When the capacitor reaches its preset value, it discharges, triggering an thyratron and opening the relay to terminate the exposure.

Thyratron It regulates the exposure automatically.

Ionization Chamber Device The x-ray beam passes through the patient and tabletop before striking the chamber. The chamber is positioned between the patient and the image receptor. It is made radiolucent so that it will not interfere with the radiographic image.

Backup Timer It is the time the electronic timer is set in case the AEC fails to terminate exposure.

150% Back up times cannot exceed the tube limit and should be set at _______ of the anticipated manual exposure mAs.

600, 2000 Regulations require that AEC's have _____ mAs and _____ mAs safety override.

600 If the AEC fails to terminate the exposure, the secondary safety circuit terminates at ____ mAs for exposures over 50 kVp.

2000 If the AEC fails to terminate the exposure, the secondary safety circuit terminates at ____ mAs for exposures below 50 kVp.

Positioning This must be absolutely accurate.

Density Controls What should not be used to compensate for patient part thickness or kVp changes?

Arcing It is a sustained luminous discharge of electricity across a gap in a circuit or between electrodes.

Open Filament It is the condition wherein the filament wire becomes thinner and eventually breaks. The xcessive heating of the filament causes the filament to vaporize. Occurs due to prolonged periods of high mA operation.

A.) The vaporized tungsten from both filament and anode.

B.) Breaking of the filament itself.

C.) Holding the rotor switch prior to making exposures.

D.) Single excessive exposures exceeding tube limits.

E.) Long exposure times. What are the causes of tube failure?

Safe Exposure Times This indicates the maximum "safe" exposure time for any selected combination of kVp and mA for a single exposure and a relatively cool tube.

A.) The type of voltage rectification (half-wave or full-wave).

B.) It varies with single- or three-phase generators.

C.) The target angle.

D.) The speed of anode rotation.

E.) It varies with the focal spot size (filament size). What are the factors affecting tube capacity?

HU = kVp x mA x seconds In Heat Units Calculation, what is the formula for the Heat units (HU) for single-phase units?

Total Anode Heat Loading Chart It is also known as the X-ray tube rating chart. This Shows the maximum exposure factors allowable for a single exposure (mA, time and kVp).

a.) Small vs. large focal spot

b.) Single- vs. three-phase generators

c.) Standard vs. high speed anode rotation The total anode heat loading chart is designed specifically for?

Anode Cooling Chart This chart determines the length of time necessary for the anode to cool before subsequent exposures can be made. This graph shows the maximum number of HU the anode can store and it also shows the rate at which it will dissipate the heat.

Housing Heat Storage It is also known as housing cooling chart. It determines heat storage capacity of tube housing and also determines heat dissipation of the tube housing.

HU = 1.35 x kVp x mA x seconds What is the formula for the heat units for three-phase 6 -pulse units?

HU = 1.40 x kVp x mA x seconds What is the formula for the heat units for three-phase 12 -pulse units?

Safe Technique Any kVp and time combination that intersects below the mA curve is considered to be a?

Heat Dissipation Heat storage capacity of tube housing is considerably greater than the anode capacity. ______________ on the other hand for tube housing is less compared to the anode.

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