what is dynamic aperture?
A.aperture that varies with transmit frequency
B.aperture that decreases as a function of time
C.aperture that increases with increasing focal length
D.aperture that changes as a function o
...
what is dynamic aperture?
A.aperture that varies with transmit frequency
B.aperture that decreases as a function of time
C.aperture that increases with increasing focal length
D.aperture that changes as a function of frame rate - ANSWER C
to which acoustic variable is penetration depth inversely related?
A.frequency
B.wavelength
C.period
D.propagation speed - ANSWER A
which imaging mode requires a broadband transducer?
A.continuous wave doppler
B.Pulsed wave doppler
C.color flow imaging
D.harmonic imaging - ANSWER B
what is the doppler shift frequency?
A.recieved ultrasound frequency multiplied by the transmitted ultrasound frequency
B.difference between the transmitted ultrasound frequency and the received ultrasound frequency
C.sum of the transmitted and received ultrasound frequencies
D.ratio of the transmitted ultrasound frequency to the received ultrasound frequency - ANSWER B
what is the potential effect of increasing the pulse repetition frequency(PRF)?
A.Depth ambiguity
B.Decreased frame rate
C.Poor spatial resolution
D.Decreased penetration - ANSWER D
what is an advantage of using pulsed wave doppler compared to continuous wave doppler?
A.higher echo sensitivity
B.ability to select sample depth
C.decreased display of aliasing
D.improved temporal resolution - ANSWER B
what affects the beam width in the near field?
A.Pulse repetition frequency
B.Pulse duration
C.Frame rate
D.Transducer aperture - ANSWER D
what is the advantage of using pulsed-wave doppler versus continuous-wave doppler?
A.allows measurement of higher velocities
B.increases range ambiguity
C.reduces the potential for aliasing
D.provides depth specificity - ANSWER D
which parameter is target group C evaluating based on the image?
A.dead zone
B.dynamic range
C.axial resolution
D.Horizontal distance accuracy - ANSWER D
What parameter is target group A evaluating based on the image? - ANSWER
which ultrasound parameter directly affects an ultrasound beam's intensity?
A.TGC
B.operating frequency
C.Output power
D.Frame rate - ANSWER C
the center frequency of a transducer depends primarily upon which characteristics of the crystal?
A.width
B.length
C.spacing
D.thickness - ANSWER D
which factor limits image frame rate?
A.transducer operating frequency
B.Sample volume size
C.Speed of sound in tissue
D.Spatial pulse length - ANSWER C
when using a 5MHZ transducer, in which tissue is the ultrasound wavelength shortest?
A.fat
B.blood
C.bone
D.muscle - ANSWER A
which term describes the averaging together of scan lines from multiple angles to create one image?
A.harmonic imaging
B.realtime three dimensional imaging
C.elastography
D.spatial compounding - ANSWER D
which variable can cause an acoustic shadow artifact?
A.small acoustic impedance mismatch
B.refraction
C.perpendicular incidence
D.low attenuation - ANSWER A
what does coded excitation improve in addition to penetration?
A.lateral resolution
B.signal-to-noise ratio
C.frame rate
D.dynamic range - ANSWER B
how is lateral resolution determined for a pulsed-echo system using a tissue-mimicking test object?
A.by observing spaces between reflectors perpendicular to the beam
B.by observing spaces between reflectors along the beam path
C.by observing position of deepest visible reflector along the beam path
D.by observing position of deepest visible reflector perpendicular to the beam path - ANSWER A
which variable caused the color change from blue to red of the vessel in this image?
A.change in vessel direction
B.color scale set to low
C.turbulent flow
D.severe stenosis - ANSWER A
which artifact is indicated by the arrows in this image?
A.shadow produced by the diaphragm
B.acoustic enhancement
C.comet tail
D.mirror image - ANSWER C
which control improves the effects of attenuation?
A.dynamic range
B.pulse inversion
C.multiple focal zones
D.time gain compensation - ANSWER D?
which doppler angle to flow results in the greatest absolute doppler shift?
A.0 degrees
B.15 degrees
C.45 degrees
D.60 degrees - ANSWER A
what term describes blood flow changes in response to respiration?
A.phasic
B.parabolic
C.spontaneous
D.pulsatile - ANSWER A
an increase in which parameter will improve the accuracy of velocity measurements with autocorrelation?
A.color field of view
B.packet size
C.wall filtering
D.transmitted frequency - ANSWER B
which harmonic imaging, how does echo frequency relate to transmitted frequency?
A.half the transmitted frequency
B.equal to the transmitted frequency
C.twice the transmitted frequency
D.four times the transmitted frequency - ANSWER C
which statement is most accurate regarding surface rendering three-dimensional ultrasound imaging?
A.improves accuracy of volume measurement
B.minimizes effect of attenuation artifacts
C.spatial resolution improve when using high resolution mesh
D.feature-based reconstruction store full three-dimensional volume acquired - ANSWER B
A.adjust the sweep speed
B.adjust the baseline
C.increasing dynamic range
D.increasing the transmitted frequency - ANSWER B
which parameter is most likely to affect spatial resolution?
A.dynamic range
B.beam width
C.system sensitivity
D.depth of visualization - ANSWER D
which imaging modality can provide the most accurate measurement of tumor volume?
A.color doppler
B.B-mode
C.A-mode
D.M-mode - ANSWER B
according to ALARA (as low as reasonably achievable) guidelines, which parameter should be minimized?
A.transmit power
B.frequency
C.time gain compensation
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