Transducers
Which of the following will NOT improve Axial Resolution?
A. increased dampening
B. increased focusing
C. increased frequency
B. increased focusing
The ratio of the largest to the smallest signal that a system can handle is termed:
A: Apodization
B: Compression
C: Threshold
D: Dynamic range
E: Pulse repetition frequency
d. dynamic range
Which of the following should be regularly checked as a component of a quality control program?
A. System penetration
B. Image uniformity
C. Assurance of electric safety
D. Distance measurement accuracy
E. All of the above
E. All of the above
You have increased the transmit power while performing a pelvic ultrasound examination. This action increases which of the following?
A. Penetration
B. Acoustic power
C. Image brightness
D. Voltage applied to the transducer elements
E. All of the above
E. All of the above
What component is necessary for a real-time B-mode scanner but is not present in A-mode scanner?
A. Clock
B. Transmitter
C. Transducer
D. Scan converter
E. Receiver
D. Scan converter
What is an advantage of single crystal- or pure-wave crystal transducer?
A) wide bandwidth
B) lower frequencies at higher resolution
C) absence of aliasing with pulsed Doppler
D) higher frame rate
E) greater steering angles
A) wide bandwidth
What parameter describes the axial length of the sampling volume for a color pixel?
A: Color sample gate
B: Packet size
C: Pulse repetition frequency
D: Pulse repetition period
E: Line density
A: Color sample gate
What is meant by the "dead zone" in performance testing?
A. B-mode penetration distance
B. Level at which the ultrasound signal is the same strength as the electronic noise
C. Doppler signal obtained at 90°
D. Doppler penetration distance
E. Distance from the transducer to the first identifiable echo
E. Distance from the transducer to the first identifiable echo
The time that it takes for one pulse to occur is known as the:
A. Duty factor
B. Spatial pulse length
C. Wavelength
D. Pulse repetition frequency
E. Pulse duration
E. Pulse duration
You have decreased the scan line density. What technique will be employed to fill in the empt data between the scan lines?
A. Interpolation
B. Rejection
C. Compression
D. Autocorrelation
E. Demodulation
A. Interpolation
You are reviewing an ultrasound image that has a sector display format that narrows to a point at the transducer surface. What kind of transducer was most likely used to acquire this image?
A) linear array
B) phased array
C) curved array
D) annular array
E) mechanical sector
B) phased array
Parabolic flow is most likely to occur with:
A: Distal to a stenosis
B: In small veins
C: In laminar flow states
D: In disturbed flow states
E: When aliasing is present
C: In laminar flow states
String test objects are used to evaluate:
A. Contrast resolution
B. Axial resolution
C. Doppler accuracy
D. Elevational resolution
E. Lateral resolution
C. Doppler accuracy
In order to display a structure on your sonographic image the sound beam must be reflected at the interface. What is required for sound reflection at the interface of two structures?
A. Oblique incidence at the interface boundary
B. Temperature differences between the two media
C. A difference in the acoustic impedance of the media
D. Different media diameters
E. Different attenuation coefficients
C. A difference in the acoustic impedance of the media
Which of the following ultrasound examinations would require the highest frame rate?
A. Small parts
B. Abdominal
C. Pelvic
D. Vascular
E. Cardiac
E. Cardiac
When you increase the scan line density in the B- mode image, you improve:
A) temporal resolution
B) contrast resolution
C) slice thickness
D) axial resolution
E) lateral resolution
E) lateral resolution
If you make a mistake in the measurement of the Doppler angle, the error in velocity estimation will be greatest at which Doppler angle?
A: 0 degrees
B: 30 degrees
C: 45 degrees
D: 60 degrees
E: 70 degrees
E: 70 degrees
Which best describes the effect of damaged transducer elements in the B-mode image?
A. Dark vertical bands beginning at the top of the image
B. Bright image
C. Cold transducer
D. Decreased frame rate
E. Horizontal banding
A. Dark vertical bands beginning at the top of the image
The mass you are imaging has a diameter of 35mm. This value can also be expressed as:
A. 350 cm
B. 0.35 cm
C. 3.5 cm
D. 35 m
E. 3.5 m
C. 3.5 cm
A type of sonographic imaging that transmits two pulses of opposite phase in rapid succession so they can be cancelled out upon reception is termed:
A. Pulse inversion harmonics
B. Compound imaging
C. Speckle reduction imaging
D. Tomographic imaging
E. Panoramic imaging
A. Pulse inversion harmonics
What type of transducer could you choose to produce a beam that is symmetrical about the beam axis?
A) annular array
B) linear sequenced array
C) phased array
D) curved array
E) tightly curved array
A) annular array
Aliasing is a potential problem in PW Doppler because of:
A: The use of high pulse repetition frequencies
B: The Doppler signal is sampled rather than recorded continuously
C: Dynamic focusing
D: The motion of the interface perpendicular to ultrasound wave propagation
E: Perpendicular incidence
B: The Doppler signal is sampled rather than recorded continuously
In an ultrasound phantom, the targets typically used for measuring axial resolution are:
A. Multiple round fluid-filled structures
B. Multiple round hyperechoic simulated lesions
C. Multiple equidistant rods
D. Closely spaced targets of varying distances
E. Long fluid-filled tubes
D. Closely spaced targets of varying distances
While performing a sonographic exam, you encounter the following interfaces. Which will produce the weakest reflected signal?
A. Organ parenchyma/fluid
B. Organ parenchyma/air
C. Organ parenchyma/organ parenchyma
D. Organ parenchyma/bone
E. Organ parenchyma/ligament
C. Organ parenchyma/organ parenchyma
What is the advantage of using write-zoom instead of read-zoom magnification?
A. Write zoom always provides a higher frame rate than read zoom
B. Write zoom allows you to select a location in the image, whereas read zoom must be applied to only the center of the image
C. Write zoom reduces the display of electronic noise and side lobes because it is performed in the memory component of the instrument
D. Write zoom provides greater dynamic range than read zoom E. Write zoom provides better spatial resolution than read zoom
E. Write zoom provides better spatial resolution than read zoom