Color Doppler Controls

Question 1

What are the two kinds of color doppler?

Answer 1

1. Velocity
2. Power (amplitude)

Question 2

Color is another way to display what information?

Answer 2

1. Frequency shift
2. Direction

Question 3

What does the color bar entail?

Answer 3

Flow direction and flow velocity.

Question 5

What does the color box entail?

Answer 5

Steer direction and sample volume size and placement.

Question 6

What does the number associated with the color bar mean?

Answer 6

It is the mean veocity assigned to color in m/sec.

Question 7

What is the color on top in a color bar assigned to?

Answer 7

Flow towards the beam.

Question 8

What color is the baseline?

Answer 8

Black.

Question 9

What is the color on the bottom of the color bar assigned to?

Answer 9

Flow away from the beam.

Question 10

Can the color bar be inverted?

Answer 10

Yes.

Question 11

How is colored formed?

Answer 11

It is formed with data fro multiple doppler beams running parallel to the color box edges.

Question 12

What must there be between the beam and flow direction?

Answer 12

An angle.

Question 13

How do you want to steer the steerbox?

Answer 13

Steer the box to the side where the vessel dives.

Question 14

In order to good a good transverse color image, how should you hold the probe?

Answer 14

Tip the pobe towards the head.

Question 15

What is the color scale initally set to for arteries?

Answer 15

.30

Question 16

What is the scale initally set to for veins?

Answer 16

.10

Question 17

What happens if the color scale is too high?

Answer 17

Lose low velocities along the wall/

Question 18

What happens if the scale is set too low?

Answer 18

Aliasing will occur.

Higher frequency shifts will wrap around and show up from the bottom.

Question 19

How should you turn on the color gain?

Answer 19

Turn the gain up until it shows outside the vessel, then turn down to show color wall to wall.

Question 20

When does aliasing occur?

Answer 20

1. Stenosis
2. Low angle
3. Scale low (PRF)
4. Tortuosity (high velocity on curves and lower angle on vertical areas)

Question 21

In long view, , how should you steer the color box in order to get the correct angle?

Answer 21

Steer the color box to the side of the vessel that dives down.

Question 22

In transverse, how shou;d you position the probe in order to get a correct angle?

Answer 22

Tilt twards the head.

Question 23

True of False:

Color doppler is another way to display frequency shifts and direction of flow besides PW spectral waves.

Answer 23

True

Question 24

What color controls are available on the duplex equipment to change the color box?

a. Box steer direction
b. Box size
c. Box placement on the screen

Answer 24

a. Box steer direction.

Question 25

The color on the top of the color bar is assigned to which type of flow? ## Footnote a. Turbulent flow b. Flow towards the doppler beam c. Normal flow d. Weak flow

Answer 25

b. Flow towards the doppler beam.

Question 26

What is the **number** at the top of the color bar? ## Footnote a. Peak velocity of the lood assigned to the very top color. b. Mean velocity of the blood assigned to the very top color. c. DIastolic velocity average shown by color doppler.

Answer 26

b. **Mean** velocity of the blood assigned to the very top color.

Question 27

True or False: The color on the bottom of the color bar will be assigned to flow running 90° to the color beam.

Answer 27

False.

Question 28

A curvy vessel may show red and blue colors at seperate areas of the vessel with black between them. This indicates\_\_\_\_\_ ## Footnote a. Flow towards the head and toward the feet at each section of the vessel. b. Flow towards the beam and away from the beam in each section of the vessel. c. High velocities demonstrating aliasing.

Answer 28

c. High velocities demonstrating aliasing.

Question 29

How do you get a color doppler angle in transverse view?

Answer 29

Point the probe towards the head.

Question 30

Name the two maneuvers done to achieve appropriate color gain?

Question 31

What do you look for in a color image of a vessel to see it as normal?

Answer 31

Color fill wall to wall with little to no aliasing.

Question 32

What is an appropriate color scale to use when you start looking in color at an **artery?** You can always adjust later. ## Footnote a. .10 b. .20 c. .30 d. 40

Answer 32

c. .30

Question 33

What will you miss if your color scale is set too high for the velocities? ## Footnote a. Low velocities b. High velocities

Answer 33

a. Low velocities.

Question 34

What will happen if you have your scale set two low for the velocities? ## Footnote a. You will miss low velocities b. Aliasing will occur. c. Color will bleed outside of the vessel.

Answer 34

b. Aliasing will occur.