Microsurgical outcome of unruptured brain arteriovenous malformations: a single-center experience

Abstract Objective We aimed to describe our single-center experience in treating unruptured brain arteriovenous malformations (uBAVMs) with microsurgical treatment. Methods During a 7-year period, 282 patients with uBAVMs were surgically treated at our institution. Patient clinical features, post-surgical complications, AVM obliteration rate, seizure control and functional outcome were collected and analyzed. Seizure control was evaluated with the Engel Seizure Outcome Scale. Patient functional outcome was assessed with modified Rankin Scale (mRS) score. Results Overall, complete obliteration was achieved in 98.2%. Surgical mortality rate was 0% and overall mortality rate was 1.1%. Good functional outcome (mRS score 0-1) was achieved in 86.9% of all patients: in 92.5% of patients with Spetzler-Martin grade I and II uBAVMs, in 80.6% of those with Spetzler-Martin grade III uBAVMs and in 62.5% of those with Spetzler-Martin grade IV and V uBAVMs. Poor outcome was significantly associated with AVM size ≥6cm, deep venous drainage, eloquent location and poor seizure control (all p