Hi and welcome!!
From what you describe, it does *sound* like a PWS but you need a physician to look at it. And, yes, you do need to point it out, even if it doesn't have anything to do with the AVM.... your physicians do need all available information.
You might write to dr. nelson (pws expert) or dr berenstein (avm expert) via our ask the expert:
http://birthmark.org/experts.php
either one of them, both probably, might have some insight!
Let us know what happens!!
Missy