Instrumentation

Question 1

Which of the following is not considered a component of an ultrasound system?

a. master synchronizer
b. pulser
c. receiver
d. image intensifier

Answer 1

d. image intensifier

Question 2

True or False?

The pulser of a mechanical transducer is typically more complex than the pulser of a phased array transducer.

Answer 2

False

Question 3

What is a typical pulser output voltage that excites a piezoelectric crystal?

a. 0.1 volts
b. 500 millivolts
c. 40 volts
d. 10 microvolts

Answer 3

c. 40 volts

Question 4

What is the typical voltage of the signal that is the input to the receiver of an ultrasound system?

a. 0.1 volts
b. 500 millivolts
c. 250 volts
d. 10 microvolts

Answer 4

d. 10 microvolts

Question 5

The output of an ultrasound pulser determines the ____ of the acoustic pulse.

a. imaging depth
b. intensity
c. duration
d. pulse repetition period

Answer 5

b. intensity

Question 6

Which one of the following does not belong in the group below?

a. receiver gain
b. energy output
c. pulser power
d. acoustic power
e. transmitter output
f. output gain

Answer 6

a. receiver gain

Question 7

True or False?

The sonographer can alter the pulser power.

Answer 7

True

Question 8

Which of the following actions will improve the signal-to-noise ratio?

a. increase dynamic range
b. increase receiver gain
c. increase output power
d. increase time-gain compensation

Answer 8

c. increase output power

Question 9

Which of these functions are performed by the receiver of an ultrasound system? (more than one answer may be correct).

a. amplification
b. threshold
c. compensation
d. demodulation

Answer 9

a. amplification

b. threshold

c. compensation

d. demodulation

Question 10

Which of the following tasks is not performed by the receiver an on ultrasound system? (more than one answer my be correct).

a. rectification
b. smoothing
c. compression
d. degaussing

Answer 10

d. degaussing

Question 11

True or False?

The sonographer can adjust the receiver gain.

Answer 11

True

Question 12

True or False?

The signal-to-noise ratio remains unchanged when a sonographer adjusts receiver gain.

Answer 12

True

Question 13

True or False?

The sonographer can make an image of uniform brightness by adjusting both output power and receiver gain.

Answer 13

False

Question 14

Which of the following is a typical value for the amplification of a signal by the receiver?

a. 50 to 100 watts
b. -50 to -100 dB
c. 50 to 100 dB
d. 5 to 25 W/cm^2

Answer 14

c. 50 to 100 dB

Question 15

What is the process of adjusting for path length related attenuation called?

a. compression
b. compensation
c. time-gain compensation
d. reconfirmation

Answer 15

b. compensation

Question 16

Which receiver function creates an image of comparable brightness from top to bottom?

a. receiver gain
b. output power
c. swept-gain compensation

Answer 16

c. swept-gain compensation

Question 17

Which transducer system is most likely to have the longest delay in its TGC curve?

a. a 5 MHz linear array
b. a 2.5 MHz annular array
c. a 7.5 MHz mechanical transducer
d. a 5 MHz annular array

Answer 17

b. a 2.5 MHz annular array

Question 18

All of the following are used to described compensation except:

a. swept gain
b. depth gain
c. time gain
d. amplitude gain

Answer 18

d. amplitude gain

Question 19

Which term best describes the region of minimum amplification on a standard TGC curve?

a. far field
b. focus only
c. area close to the transducer
d. focal zone

Answer 19

c. area close to the transducer

Question 20

What does the far gain of a depth gain compensation curve represent?

a. the median amplification related to compensation
b. the maximum amplification related to compensation
c. the minimum amplification related to compensation
d. the maximum attenuation related to compensation

Answer 20

b. the maximum amplification related to compensation

Question 21

At which imaging depth is the slope of the TGC curve most effective?

a. the region very close to the transducer
b. the far zone
c. the focal zone

Answer 21

c. the focal zone

Question 22

True or False?

The lower the frequency of the ultrasound beam, the shallower is the delay of the TGC curve.

Answer 22

False

Question 23

True or False?

Typically, the sonographer can adjust the compression function of a receiver.

Answer 23

True

Question 24

The process of demodulation incorporates which of the following tasks? (more than one answer may be correct).

a. smoothing
b. amplification
c. rectification
d. decompression

Answer 24

a. smoothing

c. rectification

Question 25

Which of the following best describes the demodulation process:

a. changing the gray scale of an image
b. changing the frequency of a signal
c. changing the form of a sound pulse
d. changing an electrical signal’s form

Answer 25

d. changing an electrical signal’s form

Question 26

True or False?

The primary purpose of demodulation is the preparation of the electrical signal for display on a television monitor.

Answer 26

True

Question 27

True or False?

Typically, the sonographer can control the demodulation process performed by a receiver.

Answer 27

False

Question 28

The process of eliminating low amplitude signals from further processing is called all of the following except ______.

a. reject
b. subordination
c. threshold
d. suppression

Answer 28

b. subordination

Question 29

True or False?

Typically, the sonographer can adjust the threshold level.

Answer 29

True