Chapter 10-11 quiz

Question 1

Which of the following transducers has the poorest axial resolution?

1. 7 MHz and 4 cycles/pulse
2. 6 MHz and 3 cycles/pulse
3. 7 MHz and 5 cycles/pulse
4. 6 MHz and 2 cycles/pulse

Answer 1

1.7 MHz and 5 cycles

Question 2

The ability to distinguish between two structures lying closely together front-to-back or parallel to the sound beam is called _________.

Answer 2

Axial resolution

Question 3

____ frequency transducers generally have the best range resolution.

Answer 3

High

Question 4

Axial resolution is measures in units of _______.

Answer 4

Distance (mm)

Question 5

The more cycles in a pulse, the ________ the numerical value of the range resolution is.

Answer 5

Greater

Question 6

If a new pulsed transducer has many cycles in its pulse, the image accuracy _______.

Answer 6

Degrades

Question 7

Two different transducers create sound pulses. One transducer is labeled 5 MHz and the other, 3 MHz. Which transducer is more likely to create a more accurate image with relation to axial resolution?

Answer 7

5 MHz

Question 8

Which of the following transducers has the best axial resolution?

1. 7 MHz and 4 cycles/pulse
2. 6 MHz and 3 cycles/pulse
3. 7 MHz and 5 cycles/pulse
4. 6 MHz and 2 cycles/pulse

Answer 8

2.6 MHz and 2 cycles/pulse

Question 9

Axial resolution describes the accuracy related to visualizing two structures that are _______ to a sound beam’s main axis.

Answer 9

Parallel

Question 10

T or F. The lower the numerical value of the longitudinal resolution, the worse the picture.

Answer 10

False

Question 11

You are purchasing a diagnostic ultrasound system. System X has axial resolution of 0.7 mm while system D’s is 0.4 mm. Based on this information, which system will produce the better quality picture?

Answer 11

System D

Question 12

Two ultrasound systems produce pulses. One pulse is 0.4 usec in duration and the other is 0.2 usec long. Which pulse is most likely to provide the best radical resolution?

Answer 12

0.2 usec system

Question 13

A sonographer is performing a study on a patient and desires superior depth resolution. Which of the following changes would create such a system?
Higher frequency
Shorter wavelength
Fewer cycles per pulse
Less ringing
All of the above

Answer 13

All of the above

Question 14

Which transducer has the worst axial resolution?
2 cycles/pulse, 4 MHz
4 cycles/pulse, 4 MHz
4 cycles/pulse, 2 MHz
2 cycles/pulse, 2 MHz

Answer 14

4 cycles/pulse, 2 MHz

Question 15

T or F. The shorter the pulse duration, the better the picture.

Answer 15

True

Question 16

T or F. One way that a sonographer can alter the axial resolution achieved during an exam is to adjust the maximum imaging depth.

Answer 16

False

Question 17

The lateral resolution of an ultrasound system is primarily determined by the _________.

Answer 17

Width of the sound pulse
or
Width of the sound beam

Question 18

T or F. When using standard ultrasonic imaging instrumentation, the lateral resolution has a higher numerical value than the axial resolution.

Answer 18

True

Question 19

Two ultrasound systems have near zone lengths of 8 cm. At the focus. system G’s lateral resolution is 3.0 mm, while system P’s is 5.0 mm. Which system will produce higher quality pictures at their foci?

Answer 19

System G

Question 20

Two ultrasound systems have near zone lengths of 8 cm. At the focus. system S’s lateral resolution is 3.0 mm, while system C’s is 5.0 mm. Which system is most likely to appropriately display two small body structures that lie, one in front of the other, at depths of 8.6 and 9.0 mm?

Answer 20

Cannot be determined

Question 21

What will lower the value of an ultrasound system’s lateral resolution?

Answer 21

Use an acoustic lens

Question 22

Two ultrasound systems have a near zone of 8 cm. At their foci, system Q’s lateral resolution is 3.0 mm and system H’s is 5.0 mm. Which system will correctly display two small structures at a depth of 8 cm? The objects are side by side and are 0.4 cm part?

Answer 22

System Q

Question 23

T or F. When using an instrument typical of today’s diagnostic imaging devices, a higher frequency transducer is likely to improve the axial resolution.

Answer 23

True

Question 24

The lateral resolution of an US system is 4mm. Two structures are separated by 3 mm and lie side by side in relation to the sound beam’s main axis. What will most likely appear on the display of the system?

Answer 24

One echo

Question 25

T or F. When using an instrument typical of today’s imaging devices, a higher frequency transducer is likely to mildly improve the system’s lateral resolution.

Answer 25

True

Question 26

The diameter of a disc-shaped, unfocused piezoelectric crystal is 1 cm. What is the best estimate for the minimum lateral resolution of the ultrasound system?

Answer 26

5 mm

Question 27

Which mode provides the foundation for real-time, gray scale anatomic imaging?

Answer 27

Brightness mode

Question 28

With B-mode, which axis is related to the strength of the reflection?

Answer 28

Z-axis

Question 29

Which imaging mode accurately displays reflector depth?

Answer 29

Amplitude mode

Question 30

What is the only display mode that provides information regarding reflector motion with respect to time?

Answer 30

Motion mode

Question 31

With M-mode, what does the Y-axis display?

Answer 31

Depth

Question 32

Which imaging modality places dots of dissimilar grayscale on the display?

Answer 32

Amplitude-mode

Question 33

With B-mode, on which axis of a CRT is the strength of the reflection input?

Answer 33

Z-axis

Question 34

To which of the following do the X-axis of a B-mode, the y axis of an M-mode and the x-axis of an A-mode all relate?

Answer 34

Time of flight

Question 35

Which imaging modality places time-of-flight information on the axis and echo-amplitude on the y-axis?

Answer 35

A-mode