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DMS 101- Ultrasound Physics > Test 2 Reading > Flashcards

Test 2 Reading Flashcards

Chapter 8 and 9 Edelman, Chapter 2 Penny

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1
Q

what is the active element in the transducer?

A

PZT lead zirconate titanate

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2
Q

What component of the transducer is 1/2 the wavelength thick?

A

active component/ PZT- Lead zirconate titanate

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3
Q

What component of the transducer is 1/4 the wavelength thick?

A

matching layer

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4
Q

3 consequences of using backing material in transducer

A

1- decreased sensitivity - less able to convert low level sound reflections into meaningful electrical signal
2- wide bandwidth
3- low quality factor

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5
Q

quality factor equation

A

quality factor = main frequency/ bandwidth

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6
Q

quality factor and ……… is directly related.

A

dampening

short dampened pulse has a lower q-factor

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7
Q

the temperature at which PZT is polarized is called ……

A

curie temperature or curie point

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8
Q

You are given 5 substances: backing material, PZT, matching layer, gel, skin. All the impedance labels have fell off. Which impedance goes with each substance when the backing material is 1.9 Mrayls.
0.8 Mrayls
1.9 Mrayls
1.6 Mrayls
2.0 Mrayls
1.0 Mrayls

A

PZT- 2.0 Mrayls
matching layer- 1.6 Mrayls
gel- 1.0 Mrayls
skin- 0.8 Mrayls

active material impedance is similar to backing material.

decrease from PZT to skin.

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9
Q

pulse length is (directly or inversely) related to pulse duration

A

directly

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9
Q

q-factor is (directly or inversely) related to bandwidth

A

inversely

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9
Q

the sensitivity of transducers that create short duration pulses is likely to be (GREATER THAN, LESS THAN, OR EQUAL TO) that of transducers that create long pulses

A

less than

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10
Q

pulse duration is (directly or inversely) related to bandwidth

A

inversely

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11
Q

all of the following correctly describe an imaging transducer except:
A- high sensitivity
B- low Q
C- wide bandwidth
D- damped

A

A- imaging transducer has low sensitivity due to backing dampening

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12
Q

T or F
shorter duration events (such as dampened pulses) are more likely to be wide bandwidth

A

True.

short= wide bandwidth
long= narrow bandwidth

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13
Q

what occurs when a PZT crystal’s temperature is elevated above the Curie point?

A

depolarization

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14
Q

What is the frequency of sound from a continuous wave transducer when the transmitter creates a 6 MHz electrical signal

A

6 MHz because electrical frequency = acoustic frequency in continuous wave transducers

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15
Q

What characteristics of the active element determine the frequency of sound created by a pulsed wave transducer?

A

1- speed of sound in the PZT
faster sound=higher frequency
2- thickness of the PZT
thicker PZT= lower frequency due to longer wavelengths

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16
Q

TRUE OR FALSE

The acoustic impedance of the matching layer is approximately the same as the acoustic impedance of skin

A

False

the impedance of the matching layer is greater than the impedance of the skin

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17
Q

TRUE OR FALSE

imaging transducers are usually of high rather than low bandwidth

A

True

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18
Q

TRUE OR FALSE

a very high Q factor transducer is used more often in diagnostic imaging transducers than a low Q factor

A

False

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19
Q

TRUE OR FALSE

A pulse with a long pulse duration is likely to have a narrow bandwith

A

True

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20
Q

TRUE OR FALSE

the damping material in a transducer increases the sensitivity

A

False

damping reduces sensitivity

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21
Q

TRUE OR FALSE

the damping material in a transducer increases the pulse length

A

False

damping shortens pulse length

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22
Q

TRUE OR FALSE

the damping material in a transducer decreases the pulse duration

A

True

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23
Q

TRUE OR FALSE

The damping material in a transducer improves the system’s lateral resolution

A

false

damping does not affect lateral resolution

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24
Q

TRUE OR FALSE

the damping material in a transducer improves the system’s longitudinal resolution

A

True

damping improves longitudinal resolution

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25
Q

TRUE OR FALSE

The damping material in a transducer decreases the bandwidth

A

false

damping increases bandwidth

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26
Q

TRUE OR FALSE

the damping material in a transducer decreases the quality factor

A

True

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27
Q

TRUE OR FALSE

if the frequency of the electrical excitation voltage of a pulsed wave transducer is 6 MHz, then the operating frequency of the transducer is 6 MHz

A

False

with pulsed wave transducers the frequency of sound is not determined by the electrical signal

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28
Q

TRUE OR FALSE

if the pulse repetition frequency of a transducer is increased, then the frequency of sound produced by the transducer remains the same

A

true

frequency and pulse repetition frequency are not related

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29
Q

TRUE OR FALSE

the diameter of the active element of a transducer helps to determine the frequency of the sound that the transducer creates

A

False

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30
Q

TRUE OR FALSE

two piezoelectric crystals are made from the same material. the thicker crystal will make a pulsed transducer with a higher frequency

A

False

thicker active elements create sound with lower frequency, not higher

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31
Q

two piezoelectric crystals are made from the same material. the thicker crystal will make a continuous wave transducer with a lower frequency

A

false

continuous wave transducer, active element thickness does not determine the sound beams frequency

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32
Q

TRUE OR FALSE

the normal propagation speed in piezoelectric material is about 3-5 times greater than that in soft tissue

A

true

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33
Q

the impedance of a transducer active element is 1,900,000 Rayls and the impedance of the skin is 1,400,000 Rayls. What is an acceptable impedance for the matching layer?
A- 1,200,000 Rayls
B- 1,400,000 Rayls
C- 1,726,000 Rayls
D- 1,950,000 Rayls

A

C

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34
Q

which of the following crystals will produce sound with the lowest frequency?
A- thin and with a low speed
B- thin and with a high speed
C- Thick and with a low speed
D- Thick and with a high speed

A

C

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35
Q

Which type of transducer has a greater Q factor?
THERAPEUTIC OR IMAGING

A

therapeutic

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36
Q

which type of transducer has a greater bandwidth
CONTINUOUS WAVE OR IMAGING

A

imaging transducers

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37
Q

which type of transducer has more backing material
THERAPEUTIC OR IMAGING

A

imaging transducers

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38
Q

in an imaging transducer, what is the purpose of attaching the backing material to the PZT?
A- increase the bandwidth
B- decrease the Q-factor
C- improve image quality
D- decrease the transducers sensitivity

A

C

The purpose of the backing material in imaging transducers is to improve image quality

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39
Q

a pulsed wave transducer has a resonant frequency of 5 MHz. The lowest frequency in the pulse is 2 MHz and the highest is 8 MHz. What is the bandwidth?

A

6 MHz

bandwidth is the range of frequencies found in a pulse
8-2=6

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40
Q

a pulsed wave transducer has a resonant frequency of 5 MHz. The lowest frequency in the pulse is 2 MHz and the highest is 8 MHz. What is the main frequency?

A

5 MHz

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41
Q

a pulsed wave transducer has a resonant frequency of 5 MHz. The lowest frequency in the pulse is 2 MHz and the highest is 8 MHz. What is the Q-factor?

A

resonant frequency / by bandwidth

5 MHz/6 MHz

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42
Q

the location where the beam is the narrowest.

For a disc shaped crystal, the width of the sound beam at the focus is 1/2 the width of the beam as it leaves the transducer

A

focal point or focus

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43
Q

the region from the transducer to the focus point

A

near field or fresnel zone

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44
Q

the region that starts at the focus and extends deeper

A

far field, fraunhofer zone

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45
Q

region around the focus where the beam is relatively narrow. Reflection arising form this are create images that are more accurate than those from other depths

A

focal zone

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46
Q

the distance from the transducer to the focus point

A

focal depth, near zone length, focal length

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47
Q

The diameter of the active element is 12 mm, and the near zone length is 8cm. The focal zone is 4 cm long.

What is the best estimate of the diameter or width of the sound beam as it exits the transducer?

A

12mm

at its beginning, the sound beam diameter is the same as the diameter of the active element

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48
Q

The diameter of the active element is 12 mm, and the near zone length is 8cm. The focal zone is 4 cm long.

what is the diameter of the sound beam at a depth of 8cm?

A

6 mm

at the end of the near zone the beam diameter is one half the transducer diameter

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49
Q

The diameter of the active element is 12 mm, and the near zone length is 8cm. The focal zone is 4 cm long.

what is the diameter of the sound beam at a depth of 16cm?

A

12 mm

at a depth equal to 2 near zone lengths the beam diameter is the same as the diameter of the active element

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50
Q

The diameter of the active element is 12 mm, and the near zone length is 8cm. The focal zone is 4 cm long.

at what depth is the focus

A

8 cm

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51
Q

The diameter of the active element is 12 mm, and the near zone length is 8cm. The focal zone is 4 cm long.

what depth marks the beginning of the focal zone?

A

6cm

the focal zone is the region around the focus.

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52
Q

The diameter of the active element is 12 mm, and the near zone length is 8cm. The focal zone is 4 cm long.

what depth marks the end of the focal zone?

A

10cm

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53
Q

The diameter of the active element is 12 mm, and the near zone length is 8cm. The focal zone is 4 cm long.

at which of the following depths is the beam narrowing?

A

6cm

54
Q

What characteristics of a fixed focus transducer determine the focal depth?

A

1) transducer PZT diameter
2) frequency of the sound

55
Q

how does the transducer diameter affect the focal depth?

A

large diameter results in a deeper focus.

transducer diameter and focal depth are directly releted

56
Q

how does frequency affect focal depth

A

higher frequency sound results in a deeper focus

frequency and focal depth are directly related

57
Q

how does high frequency sound create a deeper focus?

A

very small diameter PZT, high frequency crystals

58
Q

focal depth (mm) equation

A

= diameter (mm)^2 x frequency (MHz) / 6

or

= diameter (mm)^2 / 4 x wavelength (mm)

59
Q

A pair of 6 MHz probes are identical except for the active element diameter. The active element diameters are 6 mm and 10 mm, respectively. The sound beam of which probe will have a shallower focus

A

6 mm

smaller diameter crystals produce beams with shallower foci

60
Q

a pair of 9 mm diameter probes are identical except for frequency, which is 3 MHz and 6 MHz, respectively. Which beam will have a shallower focus?

A

3 MHz

focal depth increases with increasing frequency.

61
Q

which of the following probes creates a beam with the deepest focus?
A- 4 mm diameter, 4 MHZ
B- 6 mm diameter, 8 MHZ
C- 6 mm diameter, 2 MHZ
D- 5 mm diameter, 8 MHZ

A

B

larger diameter and higher frequency have deeper focus

62
Q

Which of the following probes creates a beam with the shallowest focus?
A- small diameter, high frequency
B- large diameter, high frequency
C- small diameter, low frequency
D- large diameter, low frequency

A

C

small diameter and lower frequency = shallow focus

63
Q

T or F
active element diameter and near zone length are directly related

A

True

64
Q

T or F
Transducer frequency and near zone length are inversely related

A

False

65
Q

T or F
Wavelength and near zone length are inversely related

A

True

shorter wavelength = higher frequency which = longer near zone due to further focal point

66
Q

describes the gradual spread of the ultrasound beam in the far field

A

beam divergence

67
Q

How does transducer diameter affect beam divergence in the far field?

A

smaller diameter crystals produce beams that spread out or diverge more in the deep far zone

crystal diameter and beam divergence are inversely related

68
Q

how does frequency alter beam divergence in the far field?

A

lower frequency sound beams spread out or diverge more in the deep far (fraunhofer) zone.

frequency and beam divergence are inversely related

69
Q

A pair of 6 MHz probes are identical except for the active element diameters, which are 6 mm and 10 mm, respectively. Which beam will be more compact in the far field?

A

10 mm

less divergent beam. larger diameter crystals produce beams that diverge less in the far field

70
Q

a pair of 9 mm diameter probes are identical except for frequencies, which are 3 MHz and 6 MHz which sound beam will spread out more in the far field?

A

3 MHz

beams are more compact as frequency increases. 3 MHz beam diverge more

71
Q

which of the following probes creates a beam with the least divergence?
A- 4 mm diameter, 4 MHz
B- 6 mm diameter, 8 MHz
C- 6 mm diameter, 2 MHz
D- 5 mm diameter, 8 MHz

A

B

highest frequency and highest diameter means more compact beam/ less divergence

72
Q

Which of the following probes creates a beam with the most divergence?
A- small diameter, high frequency
B- large diameter, high frequency
C- small diameter, low frequency
D- large diameter, low frequency

A

C

73
Q

T or F
Transducer frequency and beam divergence are inversely related

A

True

high frequency less divergent

74
Q

T or F
active element diameter and beam divergence are inversely related

A

true

larger diameter less divergent

75
Q

the frequency of a transducer does not change. if the diameter of the new piezoelectric crystal increases, what happens to the near zone length?

A

increases

76
Q

the frequency of a transducer does not change. if the diameter of the new piezoelectric crystal increases, what happens to the beam diameter in the far zone?

A

decrease

smaller diameter has more divergence so it will have larger diameter in far zone

77
Q

the frequency of a transducer does not change. if the diameter of the new piezoelectric crystal increases, what happens to the wavelength?

A

no change

78
Q

the frequency of a transducer does not change. if the diameter of the new piezoelectric crystal increases, what happens to the beam diameter in the near zone?

A

increase

79
Q

at what location is the sound beam diameter three times greater than the transducer diameter?
A- at the end of the near zone
B- at the depth equal to four focal lengths
C- at the end of the far zone
D- at the triple diameter depth

A

B

the only region where the beam diameter exceeds the transducer diameter is at depths exceeding 2 focal lengths

80
Q

what is the shape of a sound beam created by a tiny piece of PZT?

A

V- shaped

81
Q

what describes why a sound beam created by a disc shaped crystal is hourglass shaped?

A

Huygens principle

82
Q

Which of the following locations is the deepest?
A- end of the Fresnel zone
B- end of the focal zone
C- end of the Fraunhofer zone
D- end of the near zone

A

C

83
Q

Primary determinants

Pulse length
Frequency

Axial or lateral resolution

A

Axial resolution

84
Q

Primary determinants

Beam width
Depth
Gain

Axial or lateral resolution

A

Lateral resolution

85
Q

the spatial pulse length of the transducer is 0.2mm. what is the smallest distance two reflectors can be apart in order to appear as two echoes on the screen?

A

0.1mm

axial resolution is (1/2)SPL or SPL/2

86
Q

Which of the following would be considered the narrowest part of a sound beam?
A) Far Zone
B) Near Zone
C) Fresnel Zone
D) Focal Zone

A

D) focal zone

87
Q

Which of the following is the part of the transducer that stops the ringing of the element?
A) matching layer
B) housing
C) damping material
D) insulator

A

C) damping material

88
Q

Along with image depth, which of the following also determines the frame rate?
A) axial resolution
B) damping
C) number of lines per frame
D) lateral resolution

A

C) number of lines per frame

89
Q

which type of resolution is an accurate representation of moving structures?
A) lateral resolution
B) azimuthal resolution
C) spatial resolution
D) temporal resolution

A

D) temporal resolution

temporal resolution, aka, frame rate, is the ability to display moving structures in real time

90
Q

If the depth is increased and the frame rate is unchanged, what else must have decreased?
A) the pulse repetition period
B) the number of lines per frame
C) the duty factor
D) the output power

A

B)

if depth is increased then frame rate would increase but question said it didn’t. therefore, something else decreased to cancel out frame rate. the number of lines per frame is decreased, that would increase the frame rate, causing no change to the frame rate.

91
Q

Which of the following transducers can be described as having the scan lines originate from a common point of origin?
A) sector array
B) vector array
C) curvilinear array
D) linear sequenced array

A

A) sector array

comes from a point at top

92
Q

Which of the following is not a true statement about a mechanical transducer?

A) it uses a motor to steer the beam
B) most transducers are no longer mechanical
C) may be focused with a lens or phased focused
D) there are no moving parts

A

D) there are no moving parts

93
Q

Along with crystal diameter (aperture), the divergence in the far field is also determined by which of the following?
A) Spatial pulse length
B) frequency
C) propagation speed
D) line density

A

B) Frequency

94
Q

which of the following would cause a decrease in temporal resolution?
A) increased line density
B) decreased sector size
C) single transmit zone
D) increased PRF

A

A) increased line density

an increase in line density would decrease temporal resolution. All other choices would improve temporal resolution(frame rate)

95
Q

Which of the following would cause an increase in frame rate?
A) multifocusing
B) increased line density
C) increased imaging depth
D) increased PRF

A

D) increased PRF

decreasing the imaging depth, which is the same as increasing the PRF, would increase the frame rate

96
Q

Which of the following is true of the diameter of the sound beam in the fresnel zone?
A) it increases with the distance from the transducer
B) it decreases with the distance from the transducer
C) it does not change with distance from the transducer
D) it is unpredictable

A

B) it decreases with the distance from the transducer

97
Q

Which resolution typically has the lowest number in clinical imaging?
A) longitudinal
B) lateral
C) transverse
D) azimuthal

A

A) Longitudinal

LARD-
Axial resolution is better than lateral resolution

98
Q

Which of the following would most likely increase the near zone length?
A) large crystal diameter, low frequency
B) small crystal diameter, low frequency
C) large crystal diameter, high frequency
D) small crystal diameter, high frequency

A

C) large crystal diameter, high frequency

99
Q

Which of the following would most likely decrease beam divergence in the far field?
A) large crystal diameter, low frequency
B) small crystal diameter, low frequency
C) large crystal diameter, high frequency
D) small crystal diameter, high frequency

A

C) large crystal, high frequency

100
Q

Imaging transducers typically have:

A) low quality factors, wide bandwidths
B) high quality factors, narrow bandwidths
C) low quality factors, narrow bandwidths
D) high quality factors, wide bandwidths

A

A) low quality factors, wide bandwidths

101
Q

Damping material produces all of the following except:
A) decreased sensitivity
B) increases SPL
C) Wide bandwidths
D) Low-quality factors

A

B) increases SPL

it decreases SPL by decreasing the number of cycles in a pulse

102
Q

Which of the following electrical patterns produces electronic focusing of the ultrasound beam?
A) Curved
B) sloped
C) spiral
D) circular

A

A) curved

curved firing pattern of the piezoelectric elements indicates focusing of the beam

103
Q

In an unfocused, single element transducer, the width of the focal point of the sound beam measures how much compared to the beam width at the face of the transducer?
A) one-fourth
B) one-third
C) one-half
D) equal

A

C) one half

104
Q

Which of the following facilitates the transmission of sound from the element into the patient’s skin?
A) damping material
B) matching layer
C) tungsten covering
D) focusing material

A

B) matching layer

105
Q

Which of the following describes the range of frequencies present within the beam?
A) Matching layer
B) bandwidth
C) array
D) wavefront

A

B) bandwidth

106
Q

Which type of interference results in a higher amplitude sound wave?
A) Constructive interference
B) Destructive interference
C) true interference
D) false interference

A

A) constructive interference

107
Q

which of the following will not affect temporal resolution?
A) Line density
B) image depth
C) spatial pulse length
D) number of focal zones

A

C) SPL

108
Q

which of the following best describes the components of the damping material?
A) epoxy resin loaded with tungsten
B) resin made with lead zirconate titanate
C) polyvinylidene flouride
D) tungsten impregnated with lead

A

A) epoxy resin loaded with tungsten

109
Q

Which of the following is not true of the linear sequenced array transducer?
A) rectangular shape image
B) firing is sequential
C) electronically focused
D) the elements are arranged in a ring

A

D) the elements are arranged in a ring

110
Q

Which of the following is not a true statement?
A) lateral resolution varies with depth
B) a larger aperture results in a shorter near zone length
C) a larger aperture produces less divergence in the far field
D) lateral resolution may also be referred to as azimuthal resolution

A

B) a larger aperture results in a shorter near zone length

111
Q

Which of the following is not true of damping?
A) damping decreases the number of cycles in a pulse
B) damping decreases SPL
C) damping worsens axial resolution
D) damping decreases the sensitivity of the transducer

A

C) damping worsens axial resolution

is improves axial resolution by shortening the pulse

112
Q

which of the following is not a synonym for axial resolution?
A) angular
B) range
C) depth
D) radial

A

A) angular

113
Q

Temporal resolution relates to which of the following?
A) lateral resolution
B) frame rate
C) range ambiguity
D) element diameter

A

B) frame rate

114
Q

Which of the following may also be referred to as the far zone?
A) frame zone
B) Fresnel zone
C) Fraunhofer zone
D) Frankincense zone

A

C) Fraunhofer zone

115
Q

What states that waves are the result of the interference of many wavelets produced at the face of the transducer?
A) Curie’s principle
B) Snell’s law
C) Bernoulli’s law
D) Huygen’s principle

A

D) Huygens principle

116
Q

Which of the following is the resolution in the third dimension of the beam?
A) Lateral resolution
B) elevational resolution
C) contrast resolution
D) longitudinal resolution

A

B) Elevational resolution

the slice thickness

117
Q

Which of the following is true concerning the frequency and the near zone length, assuming a single element, unfocused transducer?

A) the higher the frequency, the longer the near zone length
B) the lower the frequency, the longer the near zone length
C) frequency and near zone length are not related
D) increasing the frequency causes divergence in the near field

A

A) the higher the frequency, the longer the near zone length

118
Q

which of the following is defined as changing the timing of the shocking of the elements in order to shape and steer the beam?

A) angulation
B) focusing
C) phasing
D) bundling

A

C) Phasing

method to focus/steer the beam by applying electrical impulses to the piezoelectric elements with small time between shocks

119
Q

Which of the following is not a component of spatial resolution?

A) frame resolution
B) contrast resolution
C) axial resolution
D) elevational resolution

A

A) frame resolution

spatial resolution consist of axial, lateral, elevational, and contrast

120
Q

Which transducer has no range resolution?

A) continuous wave transducers
B) curved sequenced array transducers
C) linear sequenced array transducers
D) phased array transducers

A

A) continuous wave transducer

do not time how long it takes pulses to travel so they have no range resolution

121
Q

which of the following transducers is not used for imaging?

A) continuous wave transducers
B) curved sequenced array transducers
C) linear sequenced array transducers
D) phased array transducers

A

A) continuous wave transducer

122
Q

Which of the following transducers is also referred to as a sector or vector transducer?

A) linear sequential array
B) phased array
C) continuous wave transducer
D) curved sequential array transducer

A

B) phased array

123
Q

Which of the following shortens the length of the pulse by decreasing the number of cycles in the pulse?

A) matching material
B) piezoelectric element
C) backing material
D) PZT

A

C) backing material

124
Q

Which of the following produces a pie-shaped image?
A) linear sequenced array
B) phased array
C) curved sequenced array
D) convex transducer

A

B) phased array

125
Q

The portion of the transducer that comes in contact with the patient is the

A) backing material
B) matching layer
C) wire
D) damping material

A

B) matching layer

126
Q

What does heat sterilization do to an ultrasound transducer?

A) Gives it better axial resolution
B) improves the lateral resolution of the transducer
C) kills all the bacterial and viruses
D) kills pathogens and destroys the transducer

A

D) kills pathogens and destroys the transducer

127
Q

Which of the following is defined as the minimum distance two reflectors can be, parallel to the beam, and still appear on the screen as two dots?

A) range resolution
B) angular resolution
C) contrast resolution
D) transverse resolution

A

A) range resolution

LARD
Axial resolution

128
Q

Which of the following describes the result of destructive interference?

A) the resulting wave is much larger than the original wave
B) the resulting wave is a little larger than the original wave
C) the resulting wave is smaller than the original wave
D) Destructive interference does not occur with diagnostic imaging

A

C) the resulting wave is smaller than the original wave

129
Q

to produce a transducer with a high frequency one should

A) use a thinner piezoelectric element
B) use a thicker piezoelectric element
C) use more daming
D) use less damping

A

A) use a thinner piezoelectric element

130
Q

Which of the following is not a characteristic of an unfocused single element transducer?

A) at the face of the transducer, the beam diameter is equal to the element diameter
B) at a distance of one near zone length, the beam diameter is equal to one half of the diameter of the element
C) at the distance of two near zone lengths, the beam diameter again equals the element diameter
D) at the face of the transducer, the beam diameter is twice the size of the element thickness

A

D) at the face of the transducer, the beam diameter is twice the size of the element thickness

131
Q

Which of the following would be best utilized for imaging of deep structures in the abdomen?

A) endocavitary transducer
B) linear sequenced array transducer
C) curved sequenced array transducer
D) continuous wave transducer

A

C) curved sequence array transducer

132
Q

which of the following is not a method of creating 3D images?

A) broadband technology
B) 2D array technology
C) freehand technique
D) mechanical technique

A

A) broadband technology

it permits a varity of frequencies to be used as part of imaging, but not to create 3D images.

all other option can be used

133
Q

Which of the following best describes the frame rate?

A) The frame rate is equal to the pulse repetition frequency multiplied by the lines per frame
B) The frame rate is equal to the pulse repetition frequency divided by the lines per frame
C) The frame rate is equal to the pulse repetition period divided by the lines per frame
D) The frame rate is equal to the pulse repetition period multiplied by the lines per frame

A

B) The frame rate is equal to the pulse repetition frequency divided by the lines per frame

134
Q

which of the following is represented as time, or the ability to display structures in real time?

A) temporal resolution
B) axial resolution
C) longitudinal resolution
D) contrast resolution

A

A) temporal resolution

the higher the temporal resolution, or frame rate, the better the ability to represent structures in real time

135
Q

How are ultrasound transducers typically sterilized?

A) heating to curie temp
B) cold sterilization method
C) autoclaving
D) alcohol immersion

A

B) cold sterilization method

DMS 101- Ultrasound Physics (6 decks)

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