Awake surgery for arteriovenous malformations in eloquent areas does not increase intraoperative risks and allows for shorter-term recovery and improved status

Background: Arteriovenous malformations (AVMs) located in eloquent areas are associated with a significant risk of neurologic deterioration. Awake surgery applied to intracranial AVMs could better identify eloquent areas, but its feasibility and application are controversial and limited to small case series. Methods: We retrospectively reviewed a group of 59 brain AVMs located in eloquent areas surgically treated with asleep craniotomy and compared it with a combined group of patients treated with awake craniotomy. Patients were stratified into 2 groups: patients who underwent asleep surgery and patients who underwent awake surgery. With this study, we aimed to perform a complete analysis of surgical risks and outcomes for this subgroup of patients in order to provide a basis for a future prospective study. Results: We compared the asleep group of 25 patients and the awake group of 34 patients. No statistically significant differences were identified regarding the risk of postoperative complications, surgical radicality, presence of residual, and need for adjuvant treatment (P = 1.00). The improvement in Karnofsky Performance Status (KPS) was more rapid and effective during follow-up in patients treated with awake surgery compared with asleep surgery (KPS at day 30 >70%–80% versus 87.2%, P = 0.01 and at 1year KPS >70%–80% vs. 96.9%, P = 0.02). Conclusions: In contrast to what is commonly believed, applying awake surgery to this lesion does not involve increased intraoperative risks. Still, it seems to determine a significant improvement in the outcome of patients from postoperative day 30 onwards.