Surgical Management of Adverse Radiation Effects After Gamma Knife Radiosurgery for Cerebral Arteriovenous Malformations: A Population-Based Cohort Study

Objective The goal of this study is to report our experience in the surgical treatment of cerebral arteriovenous malformations (cAVMs) related permanent symptomatic adverse radiation effects (PSAREs), to clarify an appropriate surgical management and to identify the risk factors related to their development. Methods We evaluated 549 patients treated with Gamma Knife radiosurgery (GKRS) for cAVMs with a follow-up of at least 8 years. Univariate and multivariate analyses were used to test different risk factors related to the development of PSARE. We retrospectively reviewed the records of these patients to analyze the clinical outcome. Results Fourteen patients (2.5%) developed PSARE and were submitted to surgery. Higher average treated volume represents a significant risk factors for the development of PSARE ( P P Conclusions The management of PSARE is controversial, especially for cAVMs treated with SRS. Surgical removal is rarely needed, but—if unavoidable—it can be a valuable option in experienced hands. A careful preoperative planning is always necessary to detect pathologic blood flow through the PSARE.