OBJECTIVE: The purpose of this study was to provide knowledge about long-term outcome for patients with cerebral arteriovenous malformations (AVMs) undergoing surgery.METHODS: In the period 1970-1992, 208 out of 306 patients diagnosed with AVM underwent surgery. Outcome was assessed postoperatively and at long-term follow up(median 26.6 years) in 2011. Assessment was based on the Glasgow Outcome Scale(GOS), the Modified Rankin Scale(MRS), working ability, and the presence of intracranial hemorrhage (ICH), headache, epilepsy and focal neurological deficits during the follow-up period. RESULTS: At postoperative control, 25 patients (12.1%) had deteriorated according to the Glasgow Outcome Scale. Adverse outcome correlated significantly with increasing Spetzler-Martin grade and size of the AVM. At long-term follow-up 48 patients (23.3%) were dead and 19 (9.2%) were lost to follow-up. Of the remaining 139 patients, 10 (7.2%) had a disabling neurological deficit (MRS score of ≥ 3). Nofactors with statistical power to predict adverse outcome were identified. Ten patients experienced an intracranial hemorrhage and 31 developed de novo epilepsy during follow-up. A total of 104 patients reported neurological deficits, and 34% had beenforced to leave their jobs.CONCLUSION: Cerebral AVMs are associated with increased mortality andmorbidity. Among long-term survivors after surgical treatment 58.3% were able to return to work. Our findings show that only a small proportion of the respondents(7.2%) had disabling neurological deficits at long-term follow-up. However, many of the patients have focal neurological deficits although not disabling that may haveimpact on their daily-lives.