Ch 16-17

Question 1

1. The relationship between the largest and the smallest signal amplitudes processed by a component of an US system is called the ___ and has units of ____.
   a. decibels, watts
   b. intensity, W/cm squared
   c. dynamic range, dB
   d. proportionality, dB

Answer 1

C

Question 2

2. Why is it necessary for the receiver to perform compression on the electrical signals that it processes?
   a. dynamic range of the systems electronics is less than the dynamic range of the received sound reflection
   b. the displays dynamic range of the receiver is less than the dynamic range of the image processor

Answer 2

A

Question 3

3. T or F? typically, the sonographer can adjust the compression function of a receiver.
   a. True
   b. False

Answer 3

A

Question 4

4. All of the following are consistent with an image containing only black and white and no other shades of gray except:
   a. bistable
   b. high contrast
   c. wide dynamic range

Answer 4

C

Question 5

5. Which of the following terms is not associated with a wide dynamic range image?
   a. low contrast
   b. many shades gray
   c. bistable

Answer 5

C

Question 6

6. Which of the following is associated with pulse inversion imaging?
   a. improved temporal resolution
   b. improved spatial resolution
   c. elevated frame rates
   d. high frequency phase multipliers

Answer 6

B

Question 7

7. The major benefit of pulse inversion imaging is ___ , while the primary limitation is _______
   a. harmonic imaging, decreased lateral resolution
   b. improved spatial resolution, decreased temporal resolution
   c. harmonic imaging, decreased axial resolution
   d. improved contrast resolution, decreased spatial resolution

Answer 7

B

Question 8

8. What form of behavior creates harmonics?
   a. frequency multiplication
   b. frequency inversion
   c. non-linear
   d. phase proliferation

Answer 8

C

Question 9

9. True or False. Pulse inversion harmonics uses narrow bandwidth transducers.
   a. True
   b. False

Answer 9

B

Question 10

10. All of the following are requirements of contrast agents EXCEPT:
    a. positive risk-benefit relationship
    b. long persistence
    c. smaller than red blood cells
    d. reasonable cost and/or reimbursement
    e. strong reflector of sound

Answer 10

D

Question 11

11. If the second harmonic has a frequency of 4 MHz, what is the fundamental frequency?
    a. 8 Mhz
    b. 4 Mhz
    c. 2 Mhz
    d. cannot be determined by the information presented

Answer 11

C

Question 12

12. True or False. Harmonics are multiples of the transducer frequency.
    a. True
    b. False

Answer 12

A

Question 13

13. Which of the following is associated with pulse inversion imaging?
    a. reduced temporal resolution
    b. reduced spatial resolution
    c. reduced signal to noise ratio
    d. high frequency phase multipliers

Answer 13

A

Question 14

14. Where are harmonics created?
    a. in the receiver
    b. in the transducer
    c. in the tissues
    d. in the receive transducer and tissues

Answer 14

C

Question 15

15. True or False. Pulse inversion harmonics uses wide bandwidth transducers.
    a. True
    b. False

Answer 15

A

Question 16

16. Why do contrast agents reflect sound?
    a. because the speed of sound in the agent is high
    b. because the impedance of the agent is low
    c. because the speed of sound in the agent is different than that in soft tissue
    d. because the impedance of the agent is different than the impedance of soft tissue
    e. because the agent is a gas-filled bubble

Answer 16

D