Problem questions URR Flashcards
1
Q
How will the thermal index change when increasing the overall gain to its maximum level?
a. increase
b. decrease
c. no change
d. it depends on the transmitted frequency used
A
c
2
Q
If you increase the sector angle for 45 to 90 degrees and no other console changes are made, what happens to the frame rate?
a. it doubles
b. unchanged
c. it is reduced to 1/2 the original frame rate
d. it is reduced to 1/4 the original frame rate
A
c
3
Q
Changing the depth on the image used for an m-mode tracing will change what characteristic of the display?
a. x-axis
b. y-axis
c. brightness
d. time
A
b
4
Q
When Harmonic imaging is turned on, it primarily improves ______ resolution.
a. lateral
b. contrast
c. temporal
d. axial
A
a
5
Q
Which of the following will maintain compliance with the ALARA principle?
a. reducing overall gain
b. reducing transducer frequency
c. reducing the number of images taken in standard protocol
d. minimizing the use of harmonic imaging
A
c
6
Q
In a resting patient the highest resistance in the arterial system is in the:
a. arterioles
b. venules
c. left ventricle
d. capillaries
A
a
7
Q
Axial resolution artifacts occur due to ______, while lateral resolution artifacts occur due to ______.
a. matching layer damage, element damage
b. short pulses, narrow beams
c. element damage, matching layer damage
d. long pulses, wide beams
A
d
8
Q
_______ used to form the sector shaped field of view for a phased array transducer.
a. an acoustic lens
b. electronic steering
c. electronic focusing
d. the curved arrangement of the elements
A
b
9
Q
As the element diameter decreases, the focal length ______
a. will increase
b. will remain unchanged unless the element thickness also changes
c. will decrease
d. will remain unchanged unless the frequency also changes
A
c
10
Q
The more bits per pixel, the ______ shades of grey on the image and ______ improves.
a. less, contrast resolution
b. more, slice thickness resolution
c. more, contrast resolution
d. more, spatial resolution
A
c
11
Q
Which of the following is correct regarding endocavity probes?
a. they most commonly incorporate a curved array of elements that are electronically steered to create an extended field of view
b. one of the main disadvantages of the tightly curved elements of the endocavity probe is decreased spatial resolution
c. endocavity probes offer improved lateral resolution at greater depths
d. they should be cleaned and soaked in a high level disinfectant at least once a day
A
a
12
Q
For an US system to produce a real time flicker free image the minimum frame rate required is:
a. 10 Hz
b. 15 Hz
c. 60 Hz
d. 30 Hz
A
b
13
Q
Decreasing the number of cycles in a pulse will:
a. increase the wavelength
b. improve the axial resolution of the system
c. increase the frequency of the wave
d. degrade the axial resolution of the system
A
b
14
Q
What is the method used to estimate the ankle blood pressure in a standing patient?
a. add 100 mmHg to the diastolic blood pressure
b. systolic blood pressure x2
c. ass 100 mmHg to the systolic blood pressure
d. diastolic blood pressure x2
A
c
15
Q
How is the detail resolution limit documented on phantom testing?
a. documenting the depth of the deepest pin that can be displayed
b. two separate pins are displayed as a single reflector on the image
c. documenting the width of the deepest pin displayed as a single reflector on the image
d. all 6 pins are displayed as a single reflector on the image
A
b
16
Q
What change in system controls can reduce the appearance of color displayed over vessel walls?
a. decreasing color PRF
b. decreasing color priority
c. increasing color threshold
d. increasing persistence
A
b
17
Q
The best obtainable angle of insonation for vascular evaluation that is most commonly used to provide Dopper shift information is _____ degrees.
a. 0
b. 45
c. 60
d. 90
A
c
18
Q
_______ compares each reflected echo to the same echo from a previous US pulse to determine if motion is present.
a. quadrature detector
b. registration accuracy
c. autocorrelation
d. temporal resolution
A
c
19
Q
Increasing the number of bits per pixel in an image memory will improve the:
A. detail resolution
b. contrast resolution
c. elevational resolution
d. temporal resolution
A
b
20
Q
In order to assess low velocity flow, which of the following operator adjustments should be made?
a. decrease wall filter settings and compression
b. increase scale setting
c. decrease compression
d. decrease the rejection and wall filter setting
A
d
21
Q
The sonographer may avoid aliasing by altering the:
a. transmit gain
b. image depth
c. increase the sample volume length
d. increasing the frequency
A
b
22
Q
Which of the following correctly describes how to avoid underestimation of a peak velocity measurement on a faint Doppler waveform?
a. increase the gain until the spectral window is filled in completely, then reduce slightly
b. increase the gain until all waveforms in the tracing are adequately displayed
c. increase the gain until speckle artifact is displayed across the screen, then reduce slightly
d. increase the gain until the waveform contour is smooth throughout the cardiac cycle
A
c
23
Q
A 5 MHz transducer has a PRF of 6 kHz and is being used to produce a wave with a 0.6 mm wavelength and 3mm spatial pulse length. What is the axial resolution of this system/
a. 2mm
b. 1.2mm
c. 1.5mm
d. 1mm
A
c
24
Q
______ is defined as the ratio of particle pressure to particle velocity at a given point within the US beam.
a. dynamic range
b. rarefaction
c. compression
d. impedance
A
d
25
When the color scale is increased, what other setting automatically increases along with it?
a. Doppler gain
b. wall filter
c. color threshold
d. persistence
b
26
_______ increases the strength of all of the reflected signals, regardless of reflector depth.
a. swept gain
b. TGC
c. transmit gain
d. overall gain
d
27
Which of the following requires a Doppler cursor angle of 60 degrees of less for accurate reporting of numerical values?
a. pulsatility index
b. resistive index
c. S/D ratio
d. peak systolic velocity
d
28
Mispositioned focal zones can lead to excessive ______
a. lobe artifact
b. volume averaging artifact
c. beam intensity
d. attenuation artifact
b
29
Which of the following bioeffects refers to the formation of microbubbles that burst and cause damage to tissues?
a. stable cavitation
b. mechanical index
c. transient cavitation
d. thermal energy
c
30
As the pulse repetition period decreases, ______.
a. the imaging depth increases
b. amplitude increases
c. the imaging depth decreases
d. the pulse repetition frequency decreases
c
31
Refractions occurs when a sound wave passes through an interface between two media at an oblique angle. If the propagation speed in medium 2 is greater than in medium 1, the transmitted angle of the pulse will _____.
a. increase
b. decrease
c. remain unchanged
d. change only if the interface is between air and tissue
a
32
Which of the following artifacts cause the appearance of false echoes beside the actual structure on the image?
a. refraction artifacts and mirror image artifacts
b. lobe artifacts and mirror image artifacts
c. speckle artifacts and twinkle artifacts
d. lobe artifacts and refraction artifacts
d
33
Which transducer component improves elevational resolution?
a. pulser
b. acoustic lens
c. damping layer
d. matching layer
b
34
Changing the color flow Doppler velocity scale alters the:
a. pulse repetition frequency
b. sample volume size
c. dopper shift
d. packet size
a
35
If a sound beam moves from air into soft tissue at an incident angle of 60 degrees, how will the angle of the transmitted wave change?
a. increase
b. unable to determine
c. decrease
d. remains constant
a
36
When a patient stands up, what is the hydrostatic pressure at the ankles?
a. 0 mmHg
b. 140 mmHg
c. 100 mmHg
d. 50 mmHg
c
37
While using the same type of ultrasound system, a 5MHz CW and 5 MHz PW transducer are used at the same time to evaluate blood flow in the same artery. Which transducer will produce a display of the spectral tracing first?
a. they will both produce the waveform at the same time
b. pulsed wave
c. continuous wave
d. depends on the depth of the artery
a
38
Greater than 90% of the US beam will be reflected at an interface between _____.
a. gas and tissue
b. fat and liver
c. peritoneum and muscle
d. muscle and fat
a
39
Increasing the transducer frequency will reduce the appearance of ______, while increasing the appearance of ______ on Doppler evaluation.
a. range ambiguity, aliasing
b. aliasing, blooming
c. aliasing, range ambiguity
d. clutter, ghosting
a
40
Which of the following describes a normal result for uniformity testing of the ultrasound system?
a. all images in a randomly selected exam demonstrate a constant thermal index
b. all images in a randomly selected exam demonstrate a constant mechanical index
c. images taken of the same structure with different probes of the same frequency demonstrate uniform echo amplitude between the compared images
d. TGC set to produce an image with equal echo amplitude across the screen and then when the TGC function is turned off, the echoes in the far field are reduced in amplitude
d
41
Which of the following will increase spectral broadening on the image?
a. increased sample volume size
b. increased PRF
c. increased wall filter
d. more laminar flow
a
42
Which of the following console controls can be used to increase the number of scan lines used in a color image?
a. rejection
b. overall gain
c. output power
d. persistence
d
43
The number of red blood cells in a Doppler sample is directly related to:
a. peak velocity of the flow
b. size of the spectral window
c. amount of stenosis present at the sample site
d. brightness of the waveform displayed
d
44
As the cross sectional area of a blood vessel increases, what happens to the velocity of the blood flow?
a. increases
b. remains constant
c. increases only if a stenosis is present
d. decreases
d
45
Increasing the number of pulses in a color packet will:
a. increase frame time
b. increase color priority
c. decrease color sensitivity
d. increase frame rate
a
46
Which of the following is an abnormality that would lead to an increase in the Reynolds number?
a. occlusion of an artery
b. tortuous vessel
c. thrombosis of a vein
d. stenosis of the vessel
d
47
The direction of the Doppler shift determines:
a. the color Doppler hue
b. the peak velocity of the flow
c. the average velocity of the flow
d. the color Doppler luminance
a
48
What system control can reduce the appearance of clutter on a color Doppler image?
a. decreasing color priority
b. decreasing color scale
c. increasing persistence
d. increasing color threshold
a
49
When evaluating a suspected arterial stenosis, a Doppler angle of ___ degrees will produce the most accurate flow velocity.
a. 0
b. 30
c. 60
d. 90
a
50
When the color scale is increased, what other setting automatically increases along with it?
a. color threshold
b. wall filter
c. Doppler gain
d. persistence
b
51
While scanning the carotid artery, you obtain a Doppler tracing and obtain the peak velocity. Before recording the image, you decrease the cursor angle from the last sample taken and record the new image. How will this change affect the peak velocity displayed from the new sample?
a. no change
b. decrease
c. no change unless stenosis is present
d. increase
b
52
Which of the following will increase the display of Color Doppler information on the image of a superficial mass?
a. decreased threshold
b. decreased sensitivity
c. increased probe frequency
d. increased rejection
c
53
Which of the following will lead to more color displayed in real time in the abdominal aorta?
a. decrease color threshold
b. increase frame rate
c. decrease color gain
d. increase sample size
B
54
Which of the following correctly describes a variance color map?
a. flow that demonstrates a Reynolds number greater than 2000 on color Doppler will most likely be displayed as a green color with the variance map
b. variance color maps are only used in cardiac imaging
c. the variance map replaces the blue color used in the velocity map and normal flow is displayed as a bright green color
d. variance and velocity maps are easily differentiated when evaluating normal and abnormal flow velocities
a
55
Which of the following will lead to more color displayed in real time in the abdominal aorta?
a. decrease color gain
b. increase sample size
c. decrease color threshold
d. increase persistence
d
56
Which of the following is a variable necessary to quantify the Doppler shift?
a. sine of the Doppler angle
b. transducer frequency
c. speed of sound in blood
d. all of the above are necessary for calculation of the Doppler shift
b
57
Which of the following is described as the time from pulse transmission to the time of the Doppler sample detecting the first shift?
a. spatial pulse length
b. pulse duration
c. pulse repetition period
d. packet size
c
58
Tissue Doppler imaging uses _____ settings than PW Doppler.
a. higher frequencies
b. higher filter
c. lower frequencies
d. lower filter
d
59
Which color Doppler control helps to find a balance between the accuracy of the color displayed and the temporal resolution of the image?
a. electronic steering
b. packet size
c. beam focusing
d. variance color map
b
60
How do you correct beam width artifact on a Doppler tracing?
a. decrease the PRF
b. increase the incident angle of the Doppler cursor
c. decrease the sweep speed
d. use a smaller sample size
d
61
You are evaluating an obese patient with a known abdominal aortic aneurysm. While using color Doppler to assess flow within the aortic aneurysm, minimal flow is detected in the anechoic lumen. You decrease the color scale and increase the color gain but there is no improvement. Which of the following adjustments will improve the color display on this exam?
a. increase color sample size
b. switch from a 4 MHz curved array to a 4 MHz linear array
c. increase the color threshold
d. decrease the color threshold
c
62
A Reynolds number greater than _____ indicates turbulent flow on ______ evaluation.
a. 500, PW Doppler
b. 2000, PW Doppler
c. 500, color Doppler
d. 2000, color Doppler
d
63
Which of the following parameters is displayed on the y-axis on a Doppler tracing?
a. time
b. speed
c. motion
d. frequency shift
d
64
How do you adjust your technique to reduce or eliminate cross talk on a Doppler tracing?
a. turn down the Doppler gain
b. use a smaller sample size
c. increase the PRF
d. use the same approach and incident angle but use a CW non-imaging probe
a
65
Which of the following correctly describes a limitation of the fast Fourier transformer?
a. requires a minimum of two samples per cycle to process and produce a Doppler tracing
b. cannot correctly process a frequency shift that is less than half the transducer frequency
c. cannot correctly process a frequency shift that is less than one half of the pulse repetition frequency
d. cannot process more than two samples per cycle
a
66
The magnitude of the Doppler shift in color Doppler determines:
a. the peak velocity of the flow displayed as color
b. the color luminance
c. the color hue
d. the color threshold
b
67
Which of the following are disadvantages of Power Doppler?
a. slow frame rates and flash artifact
b. twinkle artifact and limited color maps
c. aliasing and flash artifact
d. increased risk of bioeffects and aliasing
a
68
Applying transducer compression will:
a. reduce posterior shadowing seen with a malignant mass
b. improve the evaluation of peripheral vascularity of a mass
c. increase sound penetration
d. improve the evaluation of internal vascularity
c
69
Lobe artifacts:
a. always appear beside the actual structure on the image
b. only occur with linear arrays
c. always appear deeper on the image than the actual structure
d. only occur with sector arrays
a
70
Which of the following is/are responsible for a significant drop in pressure and damped pulsatility of arterial flow to allow for consistent oxygen and nutrient exchange?
a. capillaries
b. venules
c. arterioles
d. right atrium
c
71
Which of the following will reduce the appearance of lobe artifact on the image?
a. dynamic frequency tuning
b. edge enhancement
c. dynamic aperture
d. transmit focusing
c
72
What type of resolution is degraded in 2-D transducer arrays?
a. temporal
b. elevational
c. lateral
d. axial
a
73
Which system component converts the scan line data into image format for display?
a. signal processor
b. scan converter
c. image processor
d. beam former
c
74
Rayleigh scatter increases with:
a. decreasing depth
b. temperature elevation in tissue where US beam passes through
c. high velocity blood flow
d. increasing probe frequency
d
75
What beam formation technique is used to produce the sector field of view in a phased array transducer?
a. mechanical focusing
b. electronic steering
c. electronic focusing
d. mechanical steering
b
76
Which of the following is primarily responsible for the display of flow in Doppler imaging?
a. refraction
b. absorption
c. Rayleigh scattering
d. specular reflection
c
77
Which type of transducer has the smallest field of view in the near field?
a. vector
b. curvilinear
c. linear
d. sector
d
78
Which of the following should be increased when evaluating venous flow with color Doppler?
a. output power
b. PRF
c. wall filter
d. color priority
d
79
When frequency increases:
a. the wavelength increases because they are directly related
b. the wavelength decreases because they are indirectly related
c. the wavelength decreases because they are directly related
d. the wavelength increases because they are indirectly related
b
80
The rectus abdominis muscles are commonly associated with what type of artifact?
a. refraction
b. enhancement
c. comet tail
d. reverberation
a
81
What effect will increased hematocrit levels have on an arterial duplex exam?
a. hematocrit levels do not affect a Doppler evaluation
b. increased color flow display
c. decreased blood flow velocities
d. decreased blood viscosity
c
82
How can a Sonographer correct for blooming on a spectral Doppler display?
a. increase the color Doppler velocity scale
b. turn the Doppler gain down
c. decrease the color Doppler velocity scale
d. reduce the wall filter
b
83
Which of the following system functions allows the linear transducer to offer a trapezoidal field of view?
a. electronic focusing
b. apodization
c. electronic steering
d. mechanical focusing
c
84
If the output power setting is at 100% and this indicates 0dB, decreasing the power by:
a. 6dB will decrease the power output to 25% of the original power
b. 6 dB will increase the power output by a factor of 4
c. 6 dB will increase the power output by a factor of 2
d. 3dB will decrease the power output to 25% of the original power
a
85
Ultrasound can be potentially harmful to a fetus if the examination raises the temperature in the womb to a temperature greater than ____ Celcius.
a. 21
b. 41
c. 77
d. 1
b
86
Some US systems allow you to adjust the beam thickness or slice thickness. Decreasing the slice thickness will primarily improve ______ resolution.
a. axial
b. elevational
c. lateral
d. contrast
b
87
Which of the following will require the highest levels of time gain compensation?
a. 10 MHz far field
b. 5 MHz far field
c. 5 MHz near field
d. 10 MHz near field
a
88
Harmonic frequencies are generated:
a. from the edges of each piezoelectric element
b. as the reflected wave hits new tissue boundaries on the return path
c. as the sound wave travels through the medium
d. from constructive and destructive interference
c
89
Which of the following will improve the signal to noise ratio of the image?
a. increasing overall gain
b. decreasing output power
c. reducing rejection
d. use of ultrasound contrast
d
90
When a patient is supine, what is the hydrostatic pressure at the ankles?
a. 140 mmHg
b. 0 mmHg
c. 100 mmHg
d. 50 mmHg
b
91
The tissue phantom is scanned from the top. There are 6 pins separated by different millimeter intervals from each other from the top to bottom in the phantom. If you measure the minimum visible distance between the pins, what are you testing on your ultrasound system?
a. contrast resolution
b. lateral resolution
c. slice thickness resolution
d. axial resolution
d
92
No flow is detected while performing a color Doppler evaluation of a normal patent vein. What will improve the color display?
a. increasing angle of insonation
b. increase the PRF
c. decrease the color persistence
d. decrease the sample size
d
93
Range Equation: Distance to Reflector = __________
a. 1/2 propagation speed x time to reach reflector
b. propagation speed x 1/2(time to and from reflector)
c. propagation speed/time to reach reflector
b
94
Which of the following statements is true regarding equipment preparation for beginning an ultrasound exam?
a. adjust the height of the chair to allow your wrist to be fully extended while scanning
b. always place the cord around your neck or shoulder to avoid dragging the cord across open sores, wounds, or ulcers during the exam
c. a medical insurance ID number must be used to identify the patient on the ultrasound system
d. in order to reduce exam time, each image in the protocol should be recorded in 30 seconds or less
a
95
Which of the following describes a vector array transducer?
a. used for breast imaging and extremity vascular exams
b. has a sector shaped field of view with a flat top
c. uses mechanical steering
d. uses only mechanical focusing
b
96
Transmit Delay or Receive Focusing improves ______ resolution.
a. temporal
b. elevational
c. axial
d. lateral
d
97
Amplification of the received signal occurs in the:
a. image processor
b. signal processor
c. beam former
d. image former
c
98
Which of the following should be increased when evaluating venous flow on Doppler?
a. wall filter
b. output power
c. PRF
d. color priority
d
99
Which of the following beam intensity values is used to assess potential patient exposure?
a. SATP
b. SATA
c. SPTP
d. SPTA
d
100
Which of the following is an advantage of the new Capacitative Micromachined compared to traditional transducer arrays?
a. a wider bandwidth and improved detail resolution
b. a coupling gel is not needed for sound transmission
c. a narrower bandwidth and improved detail resolution
d. produces a lower intensity beam than traditional transducer of the same frequency
a
101
When the Sonographer decreases the imaging depth the:
a. frame rate will decrease
b. PRF will decrease
c. PRF will increase
d. elevational resolution will improve dc
c
102
_______ refers to the process of steering the scan lines in multiple views to evaluate tissues with several pulses with varied incident angles.
a. temporal compounding
b. frequency compounding
c. spatial compounding
d. coded excitation
c
103
What system component is responsible for 3D image acquisition and presentation?
a. beam former
b. transducer
c. signal processor
d. image processor
d
104
Increasing scan line density leads to improved _______ resolution.
a. temporal
b. spatial
c. slice thickness
d. lateral
b
105
As frequency increases, the amount of scatter ______
a. increases
b. does not change unless imaging depth changes
c. does not change unless pulse duration changes
d. decreases
a
106
Increasing the rejection or suppression setting can be used to:
a. amplify the signal of low level reflections
b. minimize the effects of attenuation
c. increase the contrast of the image to produce a more black and white image
d. reduce the appearance of shadowing artifact
c
107
What is the correct order for removal of PPE?
a. gloves, goggles, gown, mask
b. gown, goggles, gloves, mask
c. gloves, mask, goggles, gown
d. mask, gown, goggles, gloves
a
108
Increasing the spectral Doppler sample size will increase the _____
a. sweep speed
b. spectral broadening
c. Doppler shift
d. size of the spectral window
b
109
Which of the following will improve the signal to noise ratio of the image?
a. increasing overall gain
b. increasing output power
c. increasing transducer frequency
d. reducing rejection
b
110
If more cycles are added to a pulse, which of the following types of resolution is degraded?
a. contrast
b. spatial
c. lateral
d. axial
d
111
Which of the following transducers provides the best spatial resolution of the cardiac structures?
a. curved sequential array
b. phased sector array
c. vector array
d. transesophageal array
d
112
Steering the color Doppler sample box will cause changes in the:
a. transmitted frequency and PRF
b. temporal resolution and frame rate
c. frame rate and PRF
d. Doppler shift and angle of insonation
d
113
Which of the following will increase the amount of color displayed in a vessel located deep in the body?
a. decrease color gain
b. increase frame rate
c. decrease color threshold
d. increase wall filter
b
114
When evaluating a suspected arterial stenosis, a Doppler angle of _____ degrees will provide the most accurate flow velocity.
a. 0
b. 30
c. 60
d. 90
a
115
Vessel wall thickness and plaque morphology are best evaluated in 2D when the beam is at what incident angle to the vessel?
a. 0 degrees
b. 45 degrees
c. 60 degrees
d. 90 degrees
d
116
As you are scanning an obese adult patient, you notice a 2.4 Thermal index. What should be done next?
a. stop the exam and consult the radiologist regarding increased patient exposure
b. reduce the number of images obtained to significantly reduce exam time
c. take a break from scanning the patient for 30-60 seconds and then start again while monitoring the TI level
d. reduce the output power and increase the gain compensation
d
117
Abdominal Duplex exams are usually best performed with a frequency of _____ MHz and lower extremity Arterial Duplex exams are usually best performed with a frequency of ___ MHz.
a. 1-3 MHz, 5-7 MHz
b. 2-4 MHz, 8-10 MHz
c. 2-4 MHz, 5-7 MHz
d. 5-7 MHz, 8-10 MHz
c
118
Which of the following describes the difference between side lobes and grating lobes?
a. grating lobes are corrected by apodization and subdicing is used to correct side lobes
b. grating lobes are corrected by subdicing and apodization is used to correct side lobes
c. grating lobes are seen with arrays and side lobes are seen with single element probes
d. grating lobes are seen with curved arrays and side lobes are seen with linear arrays
c
119
Which of the following lists the correct equation for duty factor?
a. pulse duration/pulse repetition period
b. pulse repetition period x pulse duration/ pulse repetition frequency
c. pulse repetition period x pulse duration
d. pulse repetition period / pulse duration
a
120
Some US transducer arrays allow you to reduce the thickness of the beam as an additional type of focusing. What effect will this change have on the image?
a. improved contrast resolution
b. degraded temporal resolution
c. decreased beam attenuation
d. improved elevational resolution
d
121
In read magnification, image size and ______ increases. In write magnification, image size and ______ increases.
a. pixel size, number of pixels
b. number of pixels, pixel size
c. reflection amplitude, transmitted amplitude
d. frame rate, time of frame production
a
122
Which of the following controls will reduce the low level echoes demonstrated on the Doppler image?
a. increased compression
b. drop the baseline
c. increased wall filter settings
d. increase the Doppler gain
c
123
Which of the following is a system adjustment that is made when changing from a lower extremity venous exam on the same patient?
a. decrease doppler PRF
b. reduce the color priority
c. decrease the transducer frequency
d. reverse the color display baseline
a
124
Which of the following types of resolution varies with different depths on the image?
a. temporal resolution
b. axial resolution
c. contrast resolution
d. lateral resolution
d
125
What effect does steering the color box have on the frame rate?
a. none
b. steering to the left increases frame rate
c. steering to the right increases frame rate
d. steering to the right decreases frame rate
a
126
If the lines per frame increases and the depth remains the same, what other system parameter must change for sound wave production?
a. propagation speed of the sound produced
b. frequency
c. PRF
d. signal to noise ratio
c
127
The direction of the Doppler shift determines:
a. the color Doppler hue
b. the peak velocity of the flow
c. the average velocity of the flow
d. the color Doppler luminance
a
128
What is the difference between spatial compounding and persistence?
a. spatial compounding is only used for a 2D image, while persistence is only used in color Doppler imaging
b. spatial compounding degrades temporal resolution, while persistence improves temporal resolution
c. the imaging angle is varied between frames with spatial compounding, while persistence averages data obtained from frames obtained at the same angle
d. persistence is only used for a 2D image, while spatial compounding is only used in color Doppler imaging
c
129
Which of the following will not affect the signal to noise ratio on a 2D image?
a. harmonic imaging
b. spatial compounding
c. frequency compounding
d. temporal compounding
d
130
Which of the following is a primary factor in determining the frame rate of an ultrasound system?
a. transducer frequency
b. axial resolution
c. propagation speed in tissue
d. output power
c
131
Which of the following is an advantage of frequency compounding over spatial compounding?
a. frequency compounding reduces speckle and clutter artifacts, while spatial compounding only reduces posterior shadowing and enhancement
b. frequency compounding improves the signal to noise ratio, while spatial compounding increases reflection amplitude with no effect on the signal to noise ratio
c. frequency compounding does not affect beam intensity, while spatial compounding increases beam intensity and risk of bioeffects
d. frequency compounding does not affect temporal resolution, while spatial compounding degrades temporal resolution
d
132
_____ improves penetration and axial resolution.
a. coded excitation
b. dynamic frequency tuning
c. decreasing transducer frequency
d. spatial compounding
a
133
Which of the following will be negatively affected by spatial compounding?
a. signal to noise ratio
b. speckle reduction
c. spatial resolution
d. temporal resolution
d
134
Harmonic imaging leads to:
a. improved axial resolution but degraded lateral resolution
b. increased side lobe production
c. decreased image clutter
d. decreased signal to noise ratio
c
135
In B-mode imaging, the x-axis indicates ______ and the z-axis indicates ______
a. reflector brightness, time
b. reflector depth, reflector brightness
c. reflector depth, time
d. reflector brightness, reflector depth
b
136
Changing the sweep speed on a m-mode will change what characteristic of the display?
a. depth
b. y-axis
c. brightness
d. x-axis
d
137
Pulse inversion imaging improves ______ while degrading _____.
a. spatial resolution, contrast resolution
b. spatial resolution, temporal resolution
c. contrast resolution, spatial resolution
d. temporal resolution, contrast resolution
b
138
Increasing _____ will improve detail resolution the most on the lateral sides of the image.
a. overall gain
b. line density
c. beam width
d. image depth
b
139
If the output power setting is at 100% and this indicates 0dB, decreasing the power by:
a. 6dB will decrease the power output to 25% of the original power
b. 6dB will increase the power output by a factor of 4
c. 6dB will increase the power output by a factor of 2
d. 3dB will decrease the power output to 25% of the original power
a
140
Which of the following console controls will adjust the pulse duration?
a. output power
b. imaging depth
c. adding a focal zone
d. none of the above
d
141
As the pulse repetition period decreases, ______
a. the PRF decreases
b. the imaging depth decreases
c. amplitude increases
d. the imaging depth increases
b
142
Increasing _____ will increase the ability of the system to display fine details on the image.
a. compression
b. pulse repetition frequency
c. frequency
d. pixel density
d
143
Which of the following console controls will have NO effect on the dynamic range?
a. output power
b. suppression
c. compression
d. rejection
a
144
Which of the following will improve the signal to noise ratio of the image?
a. increasing transducer frequency
b. increasing output power
c. reducing rejection
d. increasing overall gain
b
145
A larger bandwidth leads to:
a. increased spatial pulse length
b. improved axial resolution
c. improved temporal resolution
d. degraded temporal resolution
b
146
Which of the following system adjustments can be used to help demonstrate the presence of posterior shadowing seen with gallstones?
a. decrease dynamic range
b. decrease transducer frequency
c. increasing compression setting
d. decrease the monitor contrast
a
147
Which of the following would cause artifactual debris within a simple cyst?
a. reduced gain settings
b. increased rejection settings
c. activation of spatial compounding
d. short distance from the transducer
d
148
