Landa -

We use the basic UW criteria for 50-79%, PSV >125 cm/sec and EDV <140 cm/sec.
 To break this down further, >60% stenoses we use a combination of PSV >170
cm/sec, EDV >40 cm/sec, SVR >2.0, DVR >2.4. For >70% we use ICA/CCA SVR of
>4.0.

Hope this helps.

Jason T. Card, BS, RVT
Lake Washington Vascular Labs
Bellevue/Kirkland, WA