Unit 8: Normal Doppler Flashcards
What is the ICA/CCA ratio?
Highest PSV ICA divided by PSA mid CCA
You shopuld avoid using the doppler on a curve, but if you must…what should you do?
Set center of angle cursor parallel to walls.
How should you place the doppler around a calcific shadow?
Steer SV under calcified plaque from each end.
What should you listen to post shadow?
High velocities and post-stenotic turbulence.
Make a comparison of each end of the shadow; look for big changes proximal to distal.
What are the characteristics of an ICA doppler?
- Low resistance
- Diastolic flow above zero unless in bulb.
- End diastolix velocity higher than ECA
What are the characteristic of an ECA doppler?
- High resistance
- Diastolic flow near or below zero
- End diastolic velocity lower than ICA
What are the characteristic of an CCA doppler?
- Combination of ICA and ECA
- End diastolic velocity between ICA and ECA
What are the differences between an ECA and ICA waveform?
ECA waveform: Often shows a notch in the downslope/
ICA waveform: Constant forward flow above baseline.
How do you preform a temporal tap?
- Find STA pulse in front of ear.
- Tap STA in front of ear and check for taps in waveform.
- Check opposite vessel and compare affect of tapping on each.
Why is the temporal tap useful even though it is not 100% accurate?
It is helpful if you don’t see any ECA branches in color or ECA has a similar wave shape to ICA.
How is the CCA psv proximally?
May be higher
what are the differences in the ICA psv?
- Low in bulb then higher in mid ICA
- Highest in bulb near ECA, reverses in bulb area farthest from ECA
How is the ECA psv?
Typically higher than ICA
What are the characterisitcs of a vertebral waveform?
A normal vertebral waveform is like the ICA, low resistance.
How is the SCA velocities compared to the carotid arteries?
Normall triphasic with higher psv than carotid arteries.
