Which of the following is consistent with the ALARA principle?

1. Which of the following reduces occupational injuries?

 

a. chin is slightly raised

b. eyes are even with the middle of the monitor

c. chin is slightly tucked

d. eyes are even with the top of the monitor

2. Which of the following techniques are likely performed in a laboratory?

a. ex vivo

b. in vivo

c. in utero

d. in vitro

3. Which of the following most accurately defines radiation force?

a. measurement of acoustic output

b. ability to identify weak intensities

c. ability to place echoes in the proper position

d. force exerted on the sound beam on an absorber

4. The common intensity during the extent of a pulse defines:

a. duty factor

b. pulse average

c. spatial average

d. temporal average

5. Exposure of a fetus to ultrasound is dangerous above:

a. 10° C

b. 35° F

c. 39° C

d. 41° C

6. Epidemiology studies on the biological effects of diagnostic ultrasound have determined:

a. pulse ultrasound damages soft tissue

b. no significant biological effects

c. temperatures above 39° C are dangerous to the fetus

d. focal lesion can occur at SPTA intensities greater than 10 W/cm2

7. Pressure changes in soft tissue are most likely to result in:

a. cavitation

b. tissue lesions

c. blood flow stasis

d. fetal abnormalities

8. Microbubbles will expand and collapse when:

a. pressure is applied

b. the thermal index reaches 2.0

c. the temperature of bone increases by 1° C

d. the temperature of soft tissue increases by 2° C

9. Which of the following is consistent with the ALARA principle?

a. limited exposure time and high acoustic output

b. low acoustic output and limited exposure time

c. low acoustic output and high operating frequency

d. high operating frequency and limited exposure time

10. Use of ultrasound for entertainment is:

a. approved by the FDA

b. medically approved examination

c. discouraged by the medical community

d. an excellent bonding tool for mother and fetus

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