Frederick W. Kremkau, Ph.D. Disclosuresaium.s3.amazonaws.com/uls/handouts/17POS.pdf10 Kremkau •...
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1 PRINCIPLES OF SONOGRAPHY Frederick W. Kremkau, Ph.D. Professor of Radiologic Sciences Wake Forest University School of Medicine Kremkau Disclosures Frederick W. Kremkau Relevant Financial Relationships: None Kremkau Learning Objectives After completing this presentation, the learner will be able to: 1. Explain the fundamental principle used in sonographic imaging 2. Describe the image formats used in sonography 3. Describe how echoes are generated 4. List the primary components of a sonographic transducer 5. List the primary components of a sonographic instrument 6. Describe the Doppler effect 7. List the ways in which Doppler information is presented Kremkau Lecture Outline Kremkau A. Imaging Principle B. Ultrasound C. Transducers D. Instruments E. Doppler Kremkau SONOGRAPHY sonos: [Latin] “sound” ΥραΦειν: [Greek] “to write” < Image: a representation Kremkau
Transcript of Frederick W. Kremkau, Ph.D. Disclosuresaium.s3.amazonaws.com/uls/handouts/17POS.pdf10 Kremkau •...
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PRINCIPLES OF SONOGRAPHY
Frederick W. Kremkau, Ph.D.Professor of Radiologic Sciences
Wake Forest University School of Medicine
Kremkau
DisclosuresFrederick W. Kremkau
Relevant Financial Relationships: None
Kremkau
Learning ObjectivesAfter completing this presentation, the learner will be able to:
1. Explain the fundamental principle used in sonographic imaging
2. Describe the image formats used in sonography
3. Describe how echoes are generated
4. List the primary components of a sonographic transducer
5. List the primary components of a sonographic instrument
6. Describe the Doppler effect
7. List the ways in which Doppler information is presented
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Lecture Outline
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A. Imaging PrincipleB. UltrasoundC. TransducersD. InstrumentsE. Doppler Principle
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SONOGRAPHYsonos: [Latin] “sound”ΥραΦειν: [Greek] “to write”
< Image: a representation
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1 scan line1 scan line 5 scan lines
48 scan lines 96 scan lines
192 scan lines
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sector
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• Ultrasound• Transducers• Instruments
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1 second
5 cycles per second
FREQUENCY
Number of per second.
Kremkau Kremkaucycle per second
HeinrichHertz 1890
4
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1 microsecond
5 million hertz
μεγας = large
ULTRASOUND
> 20 kHz
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My favorite frequency is 40,000 Hz.What’s yours?
30 kHz ispopular now.Have you heard it?
SPEED
LIMIT
1.54mm/µs
1.54mm/µs
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A t t e n u a t i o n
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3 MHz17 cm
5 MHz11 cm
7 MHz7 cm
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5
T
1 cm
[2 cm of travel]
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13 μs 1 cm
65 μs 5 cm
130 μs 10 cm
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Kremkau patient
piezoelectricceramicelements
dampingmaterial
matchinglayers
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3 mm
2 mm
3 mm
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Linear Array
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Convex Array
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Convex Array
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What’s going on in here?
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SIGNALPROCESSOR
IMAGEPROCESSOR
DISPLAYBEAM
FORMER
T
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SIGNALPROCESSOR
IMAGEPROCESSOR
DISPLAYBEAM
FORMER
T
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AMPLIFIER
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SIGNALPROCESSOR
IMAGEPROCESSOR
DISPLAYBEAM
FORMER
T
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amplitude detection
RF
amplitude
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SIGNALPROCESSOR
IMAGEPROCESSOR
DISPLAYBEAM
FORMER
T
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10 x 10pixels
8 x 8pixels= pictureelements
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640 x 476 = 304,640 pixels
99 x 78 = 7,722 pixels
SIGNALPROCESSOR
IMAGEPROCESSOR
DISPLAYBEAM
FORMER
T
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12 3 64 56 17 1810 50
768
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M
depth
t i m e
BEAMFORMER
T
SIGNALPROCESSOR
BEAMFORMER
T
SIGNALPROCESSOR
IMAGEPROCESSOR
BEAMFORMER
T
SIGNALPROCESSOR
IMAGEPROCESSOR
DISPLAYBEAM
FORMER
T
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Doppler Principles
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Audible Sounds
Color-Doppler Display
Spectral Display
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• Ultrasound• Transducer• Instrument• Anatomic Imaging• Motion and Flow Imaging
References1. Kremkau FW: Sonography principles and instruments, ed 9, Philadelphia, 2016, Elsevier/Saunders.2. Hedrick W: Technology for diagnostic sonography, St. Louis, 2013, Elsevier/Mosby.3. Gibbs V, Cole D, Sassano A: Ultrasound physics and technology, Edinburgh, 2009, Elsevier/Churchill.4. Hagen-Ansert S: Textbook of diagnostic sonography, ed 8, St. Louis, 2017, Elsevier/Mosby.5. Baun J: Ob/Gyn sonography, ed 2, Pasadena, 2016, Davies.
I love sonography!
PHRED'SPHUN
PHYSICS
