問題一覧
1
if the ultrasound image is too black and white, which of the following would add more levels of grey to the image
A) decrease rejection levels
2
B color can be helpful in evaluation of
C) subtle differences in tissues
3
Snell’s law describes what acoustic principle?
B) refraction
4
which of the following statements best describes the reason why there is an absence of color flow in the vessel on the image
C) the ultrasound beam is perpendicular to the motion of the blood so no flow is detected
5
which of the following has the greatest effect of resistance to blood flow?
A) Two consecutive areas of 60% stenosis in a single artery
6
____ resolution is the ability to resolve too closely space structures which lie perpendicular to the sound beam
C) lateral
7
which of the following statements is true regarding the sonographer assisting the radiologist with a biopsy procedure?
A) the sonographer‘s hands must be covered by sterile gloves when removing the biopsy device from the tray to hand the physician to start the procedure
8
In B-mode imaging the X axis indicates ____ and the z axis indicates
A) reflector depth, reflector brightness
9
activation of B-color is used to improve
A) contrast resolution
10
what is the difference between spatial compounding and persistence?
C) the imaging angle is varied between frames with spatial compounding while persistence averages data obtained from frames obtained at the same angle
11
which of the following is a primary factor in determining the frame rate of an ultrasound system?
A) propagation speed in tissue
12
The imaging depth is increased and temporal resolution is degraded. which of the following console adjustments can improve the temporal resolution
A) reduce the sector size
13
The Doppler shift is 0 when the angle between the incident beam and the flow direction is
B) 90°
14
____ refers to the number of pulses per scan line used for color Doppler imaging
A) ensemble length
15
The tissue phantom is scanned from the top. There are six pins separated by different millimeters 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?
B) axial resolution
16
which of the following is true regarding the curie point of a piezoelectric element
D) if the active PE crystal is heated to this temperature, the element will lose its piezoelectric properties
17
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?
D) decrease
18
in the diagram presents a tissue phantom the area listed as #6 is used to evaluate which of the following system parameters
D) depth penetration and the ability to detect a solid structure
19
which of the following is a correct statement describing the guidelines for wearing a mask?
D) wash your hands, tie the upper strings over your ears toward the top of your head and bottoms strings behind your neck
20
Glutaraldehyde is used to
C) disinfect the transducer after a patient exam
21
which of the following describes the best way to identify an unconscious patient
D) check the hospital wristband on the patient’s arm
22
what is the contrast resolution for a system with a 4 bit memory and 32 dB dynamic range
C) 2 dB/shade
23
which of the following describes how the u/s transducer should be clean after an exam on a patient that has an oozing incision in the area that was scanned
D) the face of the probe and the cord are thoroughly cleaned and a high-level disinfectant is used
24
which of the following producers would have the best axial resolution
B) 2 mm element thickness
25
which of the following correctly describes a normal Doppler wave form of an artery from the lower extremity
A) the triphasic wave form will have two components of anti-grade flow during the cardiac cycle
26
which of the following transducer frequencies can be used for imaging or therapeutic purposes
B) 3 MHz
27
which of the following patients would need a guardian to sign an informed consent form for an invasive procedure?
D) a patient with Alzheimer’s disease
28
What effect will increased hematocrit levels have on an arterial duplex exam
D) decreased blood flow velocities
29
which of the following console controls will have no effect on the dynamic range
C) output power
30
Which of the following will improve sliced thickness resolution
C) adding an external focusing lens
31
when scanning the thyroid you change from a 5 MHz probe to a 10 MHz probe which of the following statements is true
B) the spatial resolution will improve with the 10 MHz transducer
32
demodulation is only necessary when
A) A television monitor is used to display the image
33
which of the following techniques uses the highest intensity beam
B) PW Doppler
34
always transport the patients IV bag ____ and the urinary catheter bag ____
A) above the level of the heart, below the level of the bladder
35
dynamic focusing refers to
C) using the time of flight of pulses to improve resolution
36
Which of the following will increase the display of color Doppler information on the image of a superficial mass
C) increase probe frequency
37
which of the following describes the table placement for performing an ultrasound exam
C) table height should allow the sonographers arm to be slightly abducted with the wrist fully extended
38
Which of the following will require the highest level of time gain compensation
C) 10 MHz far field
39
what system control adjust the number of gray levels in the image to maintain the grayscale within the range of human vision
C) compression
40
which of the following is not a measurement of sound characteristics, but a calculation performed by the ultrasound system
D) blood flow velocity
41
which of the following will reduce the appearance of lobe artifact on the image?
D) dynamic aperture
42
how can a sonographer correct for blooming on spectral Doppler display
D) turn the Doppler gain down
43
which of the following can be used to eliminate aliasing on continuous Doppler tracing
D) none of the above
44
Which of the following Doppler instrument controls may be used to eliminate low frequency, high amplitude signals
B) wall filter
45
__ Is a reduction of strength of returning echoes caused by intervening highly attenuating structure
B) shadowing
46
which statement regarding high frequency transducers is correct
B) a multi hertz transducer operates at multiple frequencies and offers a broad bandwidth
47
if an ultrasound beam passes from soft tissue through a large fatty mass and then back into soft tissue, what will be displayed on the image?
D) echoes from tissues posterior to the mass would be displayed deeper on the image
48
which of the following statements best describes laminar flow
D) blood flow moves and layers with the highest velocity layer in the center of the vessel
49
When arterial stenosis present the pressure gradient and ___ will vary in order to maintain a constant ___
C) resistance, flow rate
50
When you change the PRF, this adjusts
B) number of pulses emitted per second
51
Which image demonstrates posterior enhancement
B
52
Where does the first caliper go when measuring the acceleration time on PW Doppleruse 3rd waveform
green
53
Preferred levels of axial and lateral resolution will demonstrate
B) low numerical values
54
The term ____ is described as the filling in of the spectrum window on a Doppler tracing that is caused by turbulence
B) spectral broadening
55
Capacitive Micromacgined ultrasonic transducers (CMUT)
B) use miniature elements that each contain a fixed component and flexible membrane
56
Some ultrasound systems allow you to adjust the beam thickness or sliced thickness decreasing the slice thickness will primarily improve ____ resolution
B) elevational
57
What shape is the image display for a sequential linear transducer
A) rectangle
58
When you change the angle of the Doppler cursor the ___ also changes
D) flow velocity displayed
59
If the output power setting is at 100% and this indicates 0 dB decreasing the power by:
C) 6 dB will decrease the power output by 25% of the original power
60
Which type of resolution improves the most with a short pulse duration
A) axial
61
what type of resolution is degraded in 2D transducer arrays
D) temporal