Postoperative seizure outcome in patients with cerebral arteriovenous malformations.

This study was intended to investigate the pre- and postoperative profile of seizures in the patients with cerebral arteriovenous malformations (AVMs). The patients consisted of 46 consecutive cases with supratentorial AVMs operated on from May 1987 to May 1993. Their postoperative mean follow-up duration was 60 months. The overall incidences of seizure were 50% preoperatively and 52% postoperatively, and the incidence of intractable seizure was 15% in both pre- and postoperative period. The presence of preoperative seizure and large AVM size were significant indicators of high risk of postoperative seizures (P < 0.05). About 70% of the patients with preoperative seizures showed seizures postoperatively, while those without preoperative seizures developed seizures postoperatively in 35%. Regarding postoperative intractable seizures, 57% of the group with preoperative intractable seizures remained intractable postoperatively. In conclusion, removal of AVMs did not change the overall incidence of seizures, and patients with large sized AVMs and preoperative seizure had a higher possibility of postoperative seizures.