THE X-RAY UNIT

THE BASICS

WHAT FOUR COMPONENTS ARE IN TYPICAL RADIOGRAPHIC ROOM?

1. X-RAY TUBE

2. OPERATING CONSOLE

3. HIGH VOLTAGE GENERATOR

4. X-RAY TABLE

THE X-RAY TUBEChapter 7 in Bushong

• OVERHEAD

Ceiling suspension

Sets of rails-controls longitudinal/transverse positioning

Telescoping column for controlling vertical distance.

• FLOOR

Tube-support column mounted on floor

Same positioning options as overhead

Counter weight on back of telescoping column. Why?

OTHER COMPONENTS ON X-RAY TUBE

• Collimator light

• Collimator controls

• Transverse lock

• Horizontal lock

• Longitudinal lock

• Vertical lock

• Tube head lock

• Tape Measure

• C-arm

• Protective housing– Isotrophically– Window– Useful beam– Leakage

• Acceptable level of leakage is….?

CHAPTER 6

What is the typical voltage range?

What is the typical current range?

X-RAY TABLE

• Must be radiolucent

• Can be tilted

• Float

• Holds bucky

• Has weight limit of 300lbs(Carbon-fiber)

• Easily cleaned, hard to scratch and without crevices

X-RAY CONSOLE

• Allows the radiographer to control the x-ray tube current (mA) and the voltage (kVp) so that a useful image is produced.

• ? Controls the quantity

• ? Controls the quality

• What does a line voltage compensator do?

AN R/F ROOM

• Contains a radiographic unit

• Contains a fluoroscopic unit– located under radiographic table– used in studies where it is necessary to watch a

procedure on a monitor using x-rays.

HIGH VOLTAGE GENERATOR

Housed within the x-ray room

Mobile radiography

mAs AND THE IMAGE ON THE FILM Fauber pgs 60-65

• What is mAs?

• mAs = the mA X exposure time

• mAs is the quantity of x-rays

• mAs produces the overall blackening(DENSITY) on the film

kVp and the image produced on the film (pgs 67,80-84)

• What is kVp?

• Controls the quality or penetrating quality of the x-ray beam

• Produces the varying shades of gray on the film.

Anatomic part and contrast

• Range of densities

• Tissue composition

• Page 88, figure 4-19, 4-20-4-21

Intro to Digital ImagingFauber and Carter

• Pg 79-80- Fauber

• What are some areas to be aware of?

• Carter pgs 80-82

• Does KVP matter anymore?

• Does mAs matter anymore?

Radiographic Qualities

• Photographic

• Geometric

• Allow us to see image– Density and Contrast

• Produce a sharp image– Recorded detail and

distortion

Four radiographic qualities

• Density• Contrast

------------------------• Fauber Chapter 5

• Recorded detail

• Distortion

• Overall blackness• Difference between

adjacent densities-----------------------

• Sharpness of the lines of an image

• Misrepresentation of the true size or shape of image

Controlling and influencing factors

• What might control or influence the four radiographic qualities?

• Density• Contrast• Recorded detail• Distortion• Images 4-28,4-29, 4-30, 4,31 pg 104 Fauber• Images 5-11, 5-15, Figure 5-16, all images on pg

130-131 Fauber

Sharpness vs. Visibility

• Driving on a foggy night (visibility)

• Driving after having drops in your eyes (Sharpness)

Good images vs Bad images

• Over exposed

• Over penetrated

• Poor detail

• distortion

REVIEW MODULES 2 AND 3 RADIOGRAPHIC DENSITY AND CONTRAST COMPLETEMODULE 2: RADIOGRAPHIC DENSITY EXAMMODULE 3: RADIOGRAPHIC CONTRAST EXAM

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