An adult case of recurrent arteriovenous malformation after "complete" surgical excision: a case report.

Background: Complete surgical excision of arteriovenous malformations (AVM) documented by postoperative angiography is considered a cure. However, recent reports have shown that AVMs in children may recur after negative postoperative angiograms, and some suggest that it may reflect the immaturity of their cerebrovasculature. This case report demonstrates that AVM in adults may also recur, despite postoperative angiograms confirming complete removal.

Methods: This 28-year-old man presented in 1994 with a focal motor seizure and was found to have an AVM in the right frontal lobe. He underwent surgical excision of the AVM; postoperative angiograms taken immediately after surgery and 15 days later showed no residual AVM. He remained free of symptoms after surgery and it was considered that a complete removal had been achieved. In 1998 he developed a subarachnoid hemorrhage, and subsequent angiograms revealed a small AVM in an adjacent location.

Conclusions: This is the oldest patient reported in the literature with a recurrence of AVM, despite postoperative angiograms confirming complete removal. Angiographically invisible immature vessels, which might have been left in the surgical field, might have formed a new malformation later. We still believe that such recurrence must be very rare after AVM surgery, but we now recommend follow-up angiography at yearly intervals to our patients.