Ch. 4 Flashcards Preview

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Flashcards in Ch. 4 Deck (49):
1

The pulse delays have a ______ input from the pulser but _____ output(s) to the transducer element.
a. slow; faster
b. controlled; uncontrolled
c. single; multiple
d. single; double the

c. single; multiple

2

A two-dimensional image plane is usually divided like a checkerboard in a ______ or similar matrix.
a. 1540 x 7700
b. 256 x 525
c. 1024 x 786
d. 265 x 521

c. 1024 x 786

3

The primary beam is much narrower, improving lateral resolution with ____.
a. harmonic imaging
b. pixel interpolation
c. real-time imaging
d. spatial compounding

a. harmonic imaging

4

The display form that presents the depth in the vertical axis and amplitude of the echo in the horizontal axis is _____.
a. A (amplitude) mode
b. B (brightness) mode
c. C (color) mode
d. M (motion) mode

a. A (amplitude) mode

5

The pulse repetition frequency (PRF) in real time imaging typically ranges from _____.
a. 2 - 20 MHz
b. 4 - 15 MHz
c. 5 - 50 MHz
d. 2 - 15 MHz

b. 4 - 15 MHz

6

When the fundamental frequency is filtered out, which of the following occurs?
a. volume imaging
b. pixel interpolation
c. harmonic frequencies
d. spatial compounding

c. harmonic frequencies

7

Panoramic imaging expands the image ____.
a. quality, allowing for a much smoother image
b. by using a special panoramic transducer
c. resolution
d. beyond the normal limits of a transducers field of view

d. beyond the normal limit of a transducers field of view

8

A flat panel display presents image information in the form of ______.
a. vertical lines read out from left to right
b. horizontal lines read out from left to right
c. vertical lines read out from right to left
d. horizontal lines read out from right to left

b. horizontal lines read out from left to right

9

Analog-to-digital converters convert the _____ voltage representing echoes to ____ for digital signal processing and storage.
a. analog; numbers
b. analog; bits
c. digital; analog
d. ultrasound; numbers

a. analog; numbers

10

Gain is the ratio of _____.
a. amplifier input to output voltage power
b. ampltifier output to input electric power
c. voltage ratio squared or voltage ratio to the second power
d. transmission output to amplifier input

b. amplifier output to input electric power

11

Utilizing additional focal points causes the temporal resolution to _____.
a. double
b. improve
c. degrade
d. remain unchanged

c. degrade

12

The _____ is where the action originates.
a. signal processor
b. code excitation
c. beam former
d. transmit/receive (T/R) switch

c. beam former

13

Golay codes _____.
a. are coding schemes using "gaps" or missing pulses
b. use pairs of transmitted pulses with the second being a bipolar sequence
c. are coding schemes that stack up the individual pulses
d. reduce speckle, which improves contrast resolution

b. use pairs of transmitted pulses with the second being a bipolar sequence

14

When gain is too high, which of the following occurs?
A. Contrast resolution is improved
B. Weak echoes are not imaged
C. Temporal resolution is reduced
D. Differences in echo strength are lost

D. Differences in echo strength are lost

15

The _______ determines the brightness of the echoes on the display
A. Analog-to-digital converter
B. Digitizer
C. Digital-to-analog converter
D. Cathode ray tube

C. Digital-to-analog converter

16

The ________ determines how much amplification is accomplished in the amplifier
A. TGC control
B. Postprocessing control
C. Gain control
D. Persistence control

C. Gain control

17

In which of the following code excitation techniques do ensembles of pulses drive the transducer to generate a single scanline? Time game compensation make up for:
A. Absorption
B. Attenuation
C. Reverberation
D. Refraction

B. Attenuation

18

The number of voltage pulses sent to the transducer each second is called the __________.
a. Duty factor
B. Pulse duration
C. Pulse repetition.
D. Pulse repetition frequency

D. Pulse repetition frequency

19

Pixel interpolation, persistence, and panoramic imaging are examples of _________.
A. Preprocessing
B. Spatial compounding
C. Postprocessing
D. Signal processors

A. Preprocessing

20

The averaging of sequential frames together to provide a smoother image appearance is called ____.
a. persistence
b. multi-focus
c. pixel interpolation
d. spatial compunding

a. persistence

21

Which resolution depends on penetration depth, lines per frame, and the number of focuses?
a. axial
b. temporal
c. contrast
d. detail

b. temporal

22

An analog-to-digital converter is also called a _____.
a. summer
b. digitizer
c. compression
d. signal processor

b. digitizer

23

Retention of previous frames while new echo information is added in the same scanning plane is called _____.
a. harmonic imaging
b. panoramic imaging
c. pixel interpolation
d. spatial compounding

b. panoramic imaging

24

The frequency of the _____ determines the frequency of the resulting ultrasound pulse.
a. voltage pulse
b. bandwidth
c. beam former
d. operating frequency

a. voltage pulse

25

Storage of the last several frames acquired before freezing is called ____.
a. freeze
b. triplex
c. cine loop
d. picture archiving

c. cine loop

26

What is the maximum penetration depth with a frame rate of 32 frames per second and a line density of 100 lines per frame and using only one focus?
a. 24 mm
b. 12 cm
c. 24 cm
d. 20 cm

c. 24 cm

27

The _____ drive(s) the transducer forming the beam that sweeps through the tissue to be imaged.
a. coded excitation
b. beam profiler
c. channels
d. pulser

d. pulser

28

Filtering of the sound beam is used to eliminate _______.
a. side lobe artifacts
b. secondary frequencies
c. the fundamental frequency
d. frequencies outside of the bandwidth

d. frequencies outside of the bandwidth

29

Brightness mode is also called ____.
a. B-color
b. gray-scale
c. elastography
d. volume imaging

b. gray-scale

30

Averaging sequential frames improves ______.
a. frame rate
b. dynamic range
c. temporal resolution
d. penetration depth

b. dynamic range

31

Parallel processing is a process technique that increases:
a. detail resolution
b. frame rates
c. penetration depth
d. contrast resolution

b. frame rates

32

PACS stands for _____.
a. Picture Archiving for Computer System
b. Picture and Communication System
c. Picture Archiving and Communications System
d. Pictures Allocated for Communication Storage

c. Picture Archiving and Communications System

33

Increasing the frame rate improves _____.
a. axial resolution
b. detail resolution
c. penetration depth
d. temporal resolution

d. temporal resolution

34

Displays have dynamic ranges up to _____ dB.
a. 20
b. 50
c. 100
d. 30

d. 30

35

______ determines how echo data stored in memory appear on the display.
a. preprocessing
b. postprocessing
d. dynamic range
d. color

b. postprocessing

36

Which system control equalizes amplitudes by different reflector depths?
a. persistence
b. compression
c. overall gain
d. time gain compensation

d. time gain compensation

37

How many bits does it take to make a byte?
a. 4
b. 8
c. 10
d. 15

b. 8

38

The ability of a gray-scale display to distinguish between echoes of slightly different intensities is called _____ resolution.
a. contrast
b. axial
c. spatial
d. temporal

a. contrast

39

Volume imaging is accomplished by ______.
a. acquiring many parallel two-dimensional scans
b. scanning from different angles
c. spatial compounding
d. expanding beyond the normal limits of the transducer

a. acquiring many parallel two-dimensional scans

40

The ratio of the largest to the smallest amplitude that a system can handle is called ____.
a. compression
b. dynamic range
c. demodulation
d. signal processing

b. dynamic range

41

The _____ direct(s) the driving voltages from the pulser to the transducer during transmission and directs returning echo voltages to aplifiers during reception
a. transmit/receive (T/R) switch
b. channels
c. beam former
d. signal processor

a. transmit/receive (T/R) switch

42

Which of the following techniques is considered the imaging version of palpation?
a. elastography
b. volume imaging
c. pixel interpolation
d. panoramic imaging

a. elastography

43

Which of the following digitally filters, detects, and compresses echo data?
a. beam former
b. summer
c. signal processor
d. digitzier

c. signal processor

44

To avoid echo misplacement ______.
a. penetration depth is increased
b. multiple focal zones should be utilized
c. a matching layer is added to the transducer element
d. all echoes must be received before another pulse is emitted

d. all echoes must be received before another pulse is emitted

45

Contrast resolution depends on _____ of bits per pixel.
a. size
b. number
c. strength
d. configuration

b. number

46

Which three-dimensional display appears similar to a radiograph?
a. pulse inversion
b. surface rendering
c. transparent views
d. panoramic images

c. transparent views

47

The ____ is the number of sonographic images entered into memory per second.
a. cine loop
b. frame rate
c. image refresh rate
d. pulse repetition frequency

b. frame rate

48

Which system component produces the electrical voltages that drive the transducer?
a. pulser
b. summer
c. digitizer
d. piezoelectric element

a. pulser

49

Normally the number of channels does not exceed the number of ____.
a. cycles per second
b. elements in the transducer
c. ultrasound pulses
d. pulse delays

b. elements in the transducer