What artifact displays a series of closely spaced echoes distal to a strong reflector?

1. If the amplitude of a wave doubles, the intensity will:

 

a. double

b. quadruple

c. decrease by one half

d. decrease by one tenth

2. Structures that have lower amplitude echoes than adjacent tissues are termed:

a. anechoic

b. isoechoic

c. echogenic

d. hypoechoic

 

3.For refraction to occur, which of the following must take place?

a. perpendicular incidence and a change of velocity

b. perpendicular incidence and a change in impedance

c. oblique incidence and a change of propagation speed

d. oblique incidence and a change in the transmission angle

4. Power Doppler imaging displays flow:

a. rate

b. presence

c. direction

d. characteristics

5. The concentration of scan lines within the field of view directly relates to the:

a. frame rate

b. temporal resolution

c. pulse repetition period

d. pulse repetition frequency

6. A hydrophone is an instrument used to measure:

a. cavitation

b. thermal index

c. acoustic output

d. mechanical index

7. A rise in tissue temperature is significant when it exceeds:

a. 1° C

b. 2° C

c. 5° C

d. 9° C

8. For an unfocused transducer, two near-zone lengths are equal to the:

a. transducer diameter

b. distance to the focus

c. distance to the reflector

d. active element thickness

9. What artifact displays a series of closely spaced echoes distal to a strong reflector?

a. speckle

b. multipath

c. comet tail

d. shadowin

10. Angling the color Doppler box to the right or left changes the:

a. frame rate

b. flow velocity

c. Doppler shift

d. pulse repetition frequency

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