Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Ultrasound Physics > Week 14 Real Time Imaging > Flashcards

Week 14 Real Time Imaging Flashcards

Chapter 13

1
Q

What is Frame rate?

A

The system’s ability to create numerous frames each second.
Number of frames per second.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is Frame Rate determined by?

A
  1. Sounds speed in a medium
  2. Depth
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the units of Frame rate?

A

Hz

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is temporal resolution?

A

Pertains to accuracy in time. The ability to precisely position moving structures from instant to instant.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is Temporal Resolution determined by?

A

Frame Rate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the unit for Temporal resolution?

A

Hertz or “per second”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How many lines of sound are needed to create 1 frame?

A

100

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How are frame rate and time for one frame related (T frame)?

A

Inverse and reciprocal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the formula for T frame?

A

Tframe x Frame rate = 1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

When an ultrasound system creates an image in 1/10 of a second, what is the frame rate?

A

10 Hz or 10 frames per second.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

When an ultrasound creates an image in 1/50th of a second, what is the frame rate?

A

50 Hz or 50 frames per second.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What 2 system settings affect frame rate?

A
  1. imaging depth
  2. number of pulses per frame
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What determines a high frame rate?

A

Displaying a high number of images per second.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What determines a low frame rate?

A

Displaying a low number of images per second.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How are temporal resolution and frame rate related?

A

Directly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What improves temporal resolution, High or Low frame rate?

A

High frame rate improves temporal resolution.

17
Q

How are imaging depth and frame rate related?

A

Inversely

18
Q

Does shallow imaging improve or degrade temporal resolution?

A

improves temporal resolution

19
Q

Does deeper imaging improve or degrade temporal resolution?

A

Degrades temporal resolution

20
Q

What is the formula for T frame?

A

T frame = # of pulses x PRP

21
Q

An ultrasound system creases each image with 100 distinct sound pulses. Each pulse travels to a maximum depth that requires a round trip time (PRP) of 1/1000 second. What is the time needed to make a single frame?

A

100 x 1/1000 = 1/10 second

The frame rate is 10 Hz

22
Q

Now, the sonographer decreases the depth of view by half. The PRP will be .5/1000. Since the image still requires 100 pulses, what is the T frame now?

A

100 x .0005 second
.05 or 1/20 second

Frame rate = 20 Hz.

23
Q

Shallow imaging

A
  1. Short go-return time
  2. Shorter T frame
  3. Higher frame rate
  4. superior temporal resolution
24
Q

Deeper imaging

A
  1. Long go-return time
  2. Longer T frame
  3. Lower frame rate
  4. Inferior temporal resolution
25
Q

What 3 factors determine number of pulses per frame?

A
  1. number of focal points
  2. Sector size
  3. line density
26
Q

A Multi focus transducer has what?

A
  1. Many pulses per scan line
  2. Longer T Frame
  3. Lower frame rate
  4. diminished temporal resolution
  5. improved lateral resolution
27
Q

A Single Focus transducer has what?

A
  1. One pulse per scan line
  2. Shorter T frame
  3. higher frame rate
  4. Better Temporal resolution
  5. Poorer lateral resolution
28
Q

Narrow sector size has:

A
  1. few pulses per frame
  2. shorter T frame
  3. Higher Frame Rate
  4. Superior Temporal resolution
29
Q

Wide sector size has:

A
  1. more pulses per frame
  2. longer T frame
  3. lower frame rate
  4. inferior temporal resolution
30
Q

Wide Line density has:

A
  1. widely spaced lines
  2. fewer pulses per frame
  3. Shorter T frame
  4. higher frame rate
  5. Higher temporal resolution
  6. Poor spatial resolution
31
Q

Hight Line Density has:

A
  1. tightly packed lines
  2. More pulses per frame
  3. Longer T frame
  4. Lower frame rate
  5. Low temporal resolution
  6. excellent spatial resolution
32
Q

What is the advantage of high line density?

A

The gaps between the lines are smaller therefore improving the accuracy of each individual image.

33
Q

What is line density?

A

The spacing between sound beams.

34
Q

Sector size requires what?

A

more pulses to create an image.

35
Q

Temporal resolution is better when:

A
  1. shallow imaging
  2. single focus
  3. narrow sector
  4. low line density
36
Q

Temporal resolution degrades with:

A
  1. deeper imaging
  2. multiple focal points
  3. wide sector
  4. high line density
37
Q

Lateral resolution improves with….?

A

Multi-focusing

38
Q

Spatial resolution improves with…?

A

Higher line density

39
Q
A

Ultrasound Physics (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions