Seizures are common symptoms of supratentorial arteriovenous malformations (AVMs). The potential risk factors for epilepsy in patients with AVMs are still controversial. The reported long-term outcome of seizures after surgical treatment of AVMs is variable and the data available are mainly from small retrospective case series.We identified all consecutive patients between 1990 and 2006 who underwent microsurgical resection of supratentorial AVMs at our institute. Pre-operative risk factors for seizures, intra-operative characteristics, long-term neurological disability, and seizure outcome (Engel's classification) were recorded and analyzed.During the study period, 110 patients underwent surgical resection of supratentorial AVM. Sixty of them (55 %) were symptomatic for seizures preoperatively. In our series, the absence of preoperative neurological deficits (p = 0.005), a large AVM size (p = 0.005), and no history of preoperative AVM hemorrhage (p < 0.001) were identified as risk factors for preoperative seizures. Following surgical resection, 77 % of patients with preoperative seizures had a modified Engel class I outcome. Among patients without a history of preoperative epilepsy, 56 % had new-onset seizures after surgical resection. None of the risk factors associated with preoperative seizures was associated with post-operative seizures. As there are no reliable factors predicting patients who may benefit from surgical treatment, epilepsy control should not be considered as the primary goal of AVMs surgery.
Keywords: AVM; Arteriovenous malformation; Epilepsy; Microsurgical resection; Neurosurgery.