# Dynamic Range Flashcards Preview

## Ultrasound Physics > Dynamic Range > Flashcards

Flashcards in Dynamic Range Deck (16)
1
Q

What does a high dynamic range ultrasound look like?

A
2
Q

What does a low dynamic range look like?

A
3
Q

If there was only 2 choices of gray, how would the image look like?

A

If only two, the image would have a lot of contrast, black or white.

4
Q

If there were more grays available, how would an image look like?

A

The image would show much more texture.

5
Q

What does the dynamic range of grays affect?

A

It affects the number of grays available to compare echoes.

6
Q

What is compression?

A

It is the technique that changes the dynamic range so that all parts of the equipment are on the same scale.

7
Q

How do you find the compression range?

A

uncompressed original range - compression= compression range (will be compressed, so it will be smaller)

8
Q

How do you find the original uncompressed range?

A

compressed range + compression= uncompressed range (the original is larger before it was compressed)

9
Q

If you start with DR 100 dB and compressed 60 dB, the compressed DR is?

A

40 dB→100-60=40

10
Q

If a compressed signal has a DR of 140 dB and the original signal was compressed by 30 dB, then the original DR was?

A

170 dB→140+30=170

11
Q

What does a wide dynamic range give?

A

It will give you many shades of gray in the image so that you can appreciate different tissue textures.

12
Q

What kind of contrast does a wide dynamic range give?

A

Low contrast because it shows a pleutra of grays.

13
Q

What does a narrow dynamic range give?

A

It will give you few shades of gray in the image so that you can basically only see black or white which leads you to see little or no texture.

14
Q

What kind of contrast does a narrow dynamic range show?

A

It shows a high contrast image. This means its only black and white, no grays.

15
Q

Give an example where low contrast is benefical?

A

It is helpful to see differences in plaque.

16
Q

Give an example where high contrast is beneficial.

A

May be helpful to do vein compressions so you can se the thin venous walls better.