Evaluation and Selection of Representative Images Exam Flashcards
Which one of the following structures is most likely to demonstrate strong posterior shadowing?
a. Air
b. Cysts
c. Bone
d. Blood vessel
c. Bone
There is no problem with aliasing as long as the Doppler shifts are ____ half the PRF
a. less than
b. approximately equal to
c. greater than
d. all of the above
e. none of the above
a. less than
To what is the arrow in this image pointing?
a. an IUD
b. a catheter tip
c. a biopsy needle flair
d. the endometrium
a. an IUD
Which of the following decreases the likelihood of range-ambiguity artifact?
a. increasing pulser output
b. baseline shift
c. decreasing operating frequency
d. decreasing Doppler angle
e. decreasing PRF
e. decreasing PRF
Which of the following instruments can NOT produce aliasing?
a. duplex
b. pulsed-wave doppler
c. continous-wave doppler
d. color doppler
c. continous-wave doppler
Which of the following is the opposite of echogenic?
a. sonolucent
b. isoechoic
c. hypoechoic
d. hyperechoic
a. sonolucent
When Doppler gain is set too high, which artifact is likely to occur?
a. speckle
b. location mirror image
c. aliasing
d. spectrum mirror image
e. range ambiguity
d. spectrum mirror image
Referring to image below, what is the order of image parts when they are arranged according to increasing flow speed?
a. B, C, D
b. D, C, B
c. C, B, D
d. B, D, C
c. C, B, D
If red represents a positive Doppler shift and blue represents a negative one, what color is seen for normal flow toward the transducer? What color is seen for aliasing flow toward the transducer? What colors are seen for normal flow away and for aliasing flow away from the transducer?
a. red, red, blue, blue
b. red, blue, red, blue
c. blue, red, blue, red
d. red, blue, blue, red
d.red, blue, blue, red
Propagation speed error results in improper ____ positions of a reflector on the display
a. lateral
b. axial
b. axial
Propagation speed error artifact causes has which of the following results?
a. structure missing on the display
b. structure displayed with improper brightness
c. unreal structure displayed
d. structure improperly positioned and shaped
d. structure improperly positioned and shaped
The upper limit to the pulsed waved Doppler shift that can be properly detected by pulsed instruments is called:
a. speed error
b. aliasing
c. shadowing
d. Nyquist limit
d. Nyquist limit
The best example of a mirror image artifact is seen with the:
a. diaphragm and liver
b. uterus and fallopian tube
c. gallbladder and cystic duct
d. pancreas and duodenum
a. diaphragm and liver
To decrease internally generated electronic noise in the Doppler signal, the sonographer should decrease the:
a. doppler gain
b. imaging depth
c. transducer frequency
d. overall gain
a. doppler gain
Heterogenous describes this type of mass.
a. complex mass
b. normal thyroid
c. simple cyst
d. gallstone
a. complex mass
Echoes resulting from grating lobes may be imaged if they fall within a(n) ____ region.
a. hypoechoic
b. anechoic
c. echogenic
d. complex
b. anechoic
Which of the following can correct or eliminate aliasing?
a. decreased PRF
b. decreased doppler angle
c. increased operating frequency
d. baseline shifting
d. baseline shifting
Increasing PRF to avoid aliasing can cause the following:
a. baseline shift
b. location mirror image
c. range ambiguity
d. speckly
e. spectrum mirror image
c. range ambiguity
The artifact that shows structures that exist on one side of a strong reflector as
being present on the other side as well is known as:
a. refraction
b. speed error
c. mirror image
d. range ambiguity
c. mirror image
In image below the solid line show the doppler shift. The dashed line shows the ___ result of connecting samples of the shift. To avoid aliasing in this signal, at least ____ samples would be required.
a. correct, 10
b. correct, 5
c. aliased, 5
d. aliased, 10
d. aliased, 10
