Hi - I also have a venous malformation on the left side of my face. I had 3 surgeries in 2006, 2 laser and one sclerotherapy/tissue excision. I experienced some nerve damage to this area that still seems to be healing. Just in the past few months have I been able to lift up the left corner of my mouth to semi smile. I still don't have full feeling in my lip and face area where the tissue was excised. On the bright side, the surgery went well and they were able to remove a large part of the tissue. I do still feel that I am slowly regaining feeling, so I don't think the healing is over.
Back in 1990, I had sclerotherapy when Dr. Berenstein was doing it experimentally at NYU. They were using a different hardening agent at that time, but I experienced nerve damage at that time as well. It took me years to be able to lift up my left eyebrow. But it's pretty much fine now. So I don't think it's always a permanent thing.
I would suggest attending the conference in November where you can schedule a consultation for only 50 bucks (as opposed to 200 or 250). It's worth checking out Drs. Waner and Berenstein once again. I think they do amazing work. Feel free to email me for more info.