Chapter 8 -Doppler Waveform Analysis

Question 1

Continuous wave Doppler uses how many piezo-electric crystals?

Answer 1

2

Question 2

With CW Doppler, you are able to both hear and see waveforms. True or False?

Think ABIs

Answer 2

yes.

Its when were doing ABIS, were able to both hear the waveform and also see it.

Question 3

Pertaining to Continuous wave Doppler, the qualitative data includes only the FFT and not the analog waveform.

REMEMBER: Analog is like ABis
FFT is showing the actual waveform.

True or False

Answer 3

False. Contains both

Question 4

Describe the characteristics of what a normal multiphasic/triphasic waveform would look like

Answer 4

Rapid systolic upstroke
sharp peak 
rapid mid systolic downstroke
late systolic flow reversel
forward diastolic.

Question 5

Describe the characteristics of what an ABNORMAL biphasic waveform looks like? What is different than normal?

This can also be considered normal

Answer 5

Rapid systolic upstroke and sharp peak is the same.

Slower downstroke of systolic flow

There is a late systolic flow reversal like seen in normal

NO FORWARD diastolic flow.

Question 6

Describe the abnormal characteristics of monophasic flow. When scanning, monophasic flow should indicate disease

Answer 6

Delayed systolic upstroke

rounded peak (not sharp peak like normal)

No flow reversal

Slowed mid systolic down-stroke

Question 7

In what instance, could you see a normal/near normal signal even when there is occlusions or stenosis?

Answer 7

If there is well collateralization

Question 8

If you see a waveform that has a more rounded appearance, what would you suspect?

looks almost like venous flow…

Answer 8

an occlusion with poor collateralization.

Question 9

How is the pulsatility index calculated? what are they measuring?

Answer 9

you’re basically measuring peak to peak. So peak of the systolic to peak of the diastolic. Usually the computer will calculate this for you.

Question 10

When calculating the PI (pulsatility index) what is considered normal and abnormal?

Answer 10

Normal is GREATER than for 4.0

Abnormal is LESS than 4.0 (60% stenosis proximal to sample)

Question 11

What is the acceleration time (AT) calculated for?

Answer 11

to see if there’s a delay in the systolic upstroke. If there is, this could indicate proximal obstruction.

Question 12

What is considered normal and abnormal in “Acceleration Time”

Answer 12

Normal is LESS THAN 133 milliseconds

Abnormal is MORE than 133 milliseconds (proximal obstruction)

Question 13

If you see an acceleration time of 180 milliseconds in common femoral artery, what should you suspect?

Answer 13

Proximal obstruction in the iliacs.. that is an abnormal AT.

Question 14

If there is an occlusion in blood flowing into the lower extremities is considered _______ disease.

For example an occlusion in the iliacs

inflow or outflow?

Answer 14

inflow

Question 15

An occlusion in an artery that the blood is flowing out of the extremity is considered ___ disease?

For example, an occlusion in the femoral/popliteal

Inflow or outflow?

Answer 15

outflow.

Question 16

Post-exercise-

If we see a waveform that appears to have a slower upstroke and a rounded peak and no reverse component than it did before exercise, what could that indicate?

Answer 16

that is abnormal, there is likely an obstruction.

Question 17

The subclavian, axillary and brachial arteries have more (high or low?) resistant flow patterns?

Answer 17

high resistant

q

Question 18

Waveforms at the wrist tend to be more variable. Which would we see more often?

high or low resistant?

Answer 18

Low resistant.