ch21-22

20問 • 1年前

問題一覧

Where is the mirror image artifact located? A. sometimes shallower on the image that in the body B. always deeper on the image than in the body C. sometimes the same depth on the image as in the body D. never deeper on the image than in the body

While imaging a test object, an ultrasound system displays one image 1.8 cm deeper than another. Upon measuring the test object, it is found that it is actually 2.0 cm deeper. What conclusion can be drawn from this? A. speed of sound in the test object is the same as soft tissue B. speed in test object is less than that in soft tissue C. attenuation of sound in the test object is less than in soft tissue D. speed in soft tissue is less than that of the test object

If an ultrasound pulse travels through a large mass in the body at a speed of 1.2 mm/us, what happens to the position of all echoes produced from reflectors shallower than the mass? A. they are placed too shallow a location on the image B. they are placed in too deep a location on the image C. they are likely to be placed at the correct depth

What type of artifact causes a reflection to be placed at an incorrect depth? A. lateral incertitude B. shadowing C. range ambiguity D. indeterminate relaxation

With standard diagnostic imaging instrumentation, which has the higher numerical value? A. axial resolution B. lateral resolution C. elevational resolution

How does slice thickness artifact commonly express itself? A. fill in of cystic structures B. improper brightness of reflectors C. absence of reflectors D. strong linear echoes

With depth resolution, _______. A. too many reflections appear on the image B. reflections are placed too deep on the image C. too few reflections are on the image D. reflectors appear too shallow on the image

2 small cysts, positioned perpendicular to the main axis of a sound beam, are 2.4 mm apart. What determines whether they appear as 2 distinct images on the system's display? A. beam width B. pulse length C. PRF D. TGC

Which artifact is not related to the unexpected reflection of an acoustic wave? A. multipath B. comet tail C. reverberation D. lateral resolution

All artifacts are errors in imaging that do not represent the true anatomy of the image organ. Therefore, they are all undesirable and should be eliminated if possible. A. True B. False

false

What is the comet tail artifact's fundamental mechanism of formation? A. reflection B. rarefaction C. refraction D. attenuation

What is true of acoustic speckle? (& Multipath) A. its effects are mild, and it tends to slightly degrade images B. it is a rare artifact that does not occur in real-time imaging C. its effects are dramatic D. it is eliminated with apolarization

Propagation speed errors cause A. reverberation or ring down B. shadowing C. enhancement D. incorrect axial placement

False echoes are produced from A. rarefaction B. reverberation C. diffraction D. edge shadow

The improper location of an echo may result from A. shadowing B. diffraction C. propagation speed error D. enhancement

When the refractive index of water is slightly altered by a sound beam that causes compression and rarefaction of the water molecules the phenomenon becomes the bases for measuring the beam by the __________ technique A. isoamplitude B. relative echo C. Schlieren D. AIUM test

What standard is best used in a quality assurance program? A. subjective B. expert C. objective D. legislative

All of the following are characteristics of a tissue equivalent phantom except: A. speed of sound similar to that in soft tissue B. attenuation properties similar to that of soft tissue C. scattering characteristics similar to that of soft tissue D. density similar to that of soft tissue

Which of the following is different for a tissue equivalent phantom and an AIUM 100mm test object? A. propagation speed of sound B. wavelength of sound C. attenuation of sound D. frequency of sound

All of the following may be used to evaluate Doppler systems except: A. tissue equivalent phantom B. moving belt phantom C. vibrating string phantom D. Doppler phantom

ch 6 AP

ユーザ名非公開 · 20問 · 1年前

ch 6 AP