Chapter 5- LEA Duplex Imaging Flashcards
What are the two places within a stenosis to document for the stenosis profile ??
Pre-stenotic PSV to the highest intra-stenotic PSV.
If there is a 2:1 ratio increase between pre-stenotic PSV and intra-stenotic PSV, this indicates a >___% diameter reduction
50%
If there is a 4:1 ratio increase between pre-stenotic PSV and intra-stenotic PSV, this indicates a >___% diameter reduction
75%
What is the difference between inflow collaterals and outflow collaterals when it comes to arterial occlusions?
The inflow collaterals are located at point of vessel reconstitution ( or where the vessel opens distally). When we see an inflow collateral, we need to thinkPROXIMAL obstruction.
The outflow collaterals are at the point of occlusion
How dilated does an artery have to be to be considered an aneurysm?
> 1 1/2 times the diameter of adjacent artery.
What is the most common complication for a peripheral aneurysm?
Embolization
What is the aneurysm rule?
Patients with an aneurysm in one location is more often to have one elsewhere.
> 400 cm/sec increase in velocity intra-stenosis is considered a ___ diameter reduction.
75%
What kind of change in resistance would there be in an occluded artery?
Goes from high resistive to low resistive monophasic.
If we see a delayed systolic acceleration time, what should we suspect?
proximal stenosis
If we see an artery that goes from triphasic to biphasic or monophasic, what should we suspect?
Stenosis between the two locations you document. Say you took the CFA and it was triphasic and then you do the pop artery and its monophasic. There is likely something between the CFA and the pop
In regards to an occluded artery:
Outflow collaterals will be where?
at the point of the occlusion
In regards to an occluded artery.
Inflow collaterals will be where?
point of vessel reconstitution.
