Recurrence of Cerebral Arteriovenous Malformations Following Resection in Adults: Does Preoperative Embolization Increase the Risk?

BACKGROUND: Complete surgical resection of arteriovenous malformations (AVMs), documented by postoperative angiography, is generally felt to represent cure, obviating the need for long-term follow-up imaging. Although AVM recurrence has been reported in the pediatric population, this phenomenon has only rarely been documented in adults. Recurrence after treatment solely with embolization, however, has been reported more frequently. Thus, patients undergoing multimodal therapy with surgery following preoperative embolization may also be at higher risk for recurrence. OBJECTIVE: To determine if preoperative embolization contributes to recurrences of AVMs after complete surgical resection. METHODS: A retrospective study of patients undergoing AVM resection was performed. Those with complete surgical AVM resection, confirmed by negative early postoperative cerebral angiography and with available follow-up angiographic imaging >6 months postoperatively were included. RESULTS: Two hundred three patients underwent AVM resection between 1995 and 2012. Seventy-two patients met eligibility criteria. There were 3 recurrences (4%). Deep venous drainage and diffuse type of AVM nidus were significantly associated with recurrence. Although preoperative embolization did not reach statistical significance as an independent risk factor, radiographic data supported its role in every case, with the site of recurrence correlating with deep regions of nidus previously obliterated by embolization. CONCLUSION: AVM recurrences in the adult population may have a multifactorial origin. Although deep venous drainage and diffuse nidus are clearly risk factors, preoperative embolization may also be a contributing factor with the potential for recurrence of unresected but embolized portions of the AVM. Follow-up angiography at 1 to 3 years appears to be warranted.