Norma, sounds like Klippel-Trenaunay Syndrome. The book states the a-v
fistulas are microscopic type communicators, may be hard to see. Hope this
helps. Carol Vandenberg, RN, RVT

Norma VandenBerghe wrote:

> I have a question about using duplex US to identify and localize
> congenital arterio-venous malformations.  I have had a few cases through
> the years, and have not really had much luck with tracking the little
> devils down.  I have been able to predict a couple of intracranial cases
> based on the differences between the flow signals in the two carotid
> arteries.  But in the extremities, as on the child I saw today with
> hugely distended veins and even small venous ulcerations on his left
> leg, they have remained elusive.  I looked at the entire arterial system
> for low resistance or turbulence;  I looked at the entire venous system
> for arterialized flow, pulsation, etc.  And found nothing.  No
> difference compared to the same site on the unaffected right leg.  I
> looked at iliacs and all the way down the leg.  I tried to just look for
> abnormal color flow.  I looked with velocity scale set high.  Set low.
> Gain up, down etc. Nothing.
>
> Have others had more success than I have?  I feel like I must be
> overlooking something.
> Thanks!   Norma V.