Seizure outcome in children treated for arteriovenous malformations using gamma knife radiosurgery.

Seizures are the second most common presenting symptom of arteriovenous malformations (AVMs) in children. Although radiosurgery has been found to be a safe and effective alternative treatment, the outcome of seizure control in children after radiosurgery for AVMs is unknown. Between 1987 and 1994, 72 children under the age of 18 years were treated with gamma knife radiosurgery for AVMs at our institution. Fifteen patients (21%) had seizures as part of their clinical course. There were 11 boys and 4 girls with ages varying from 2 to 17 years (median 16 years). Seizures included: generalized tonic-clonic (n = 8); focal motor or sensory (n = 4); partial complex (n = 2), and a combination of generalized and partial complex (n = 1). Nine lesions were in cortical locations; six were subcortical. Spetzler-Martin grades included: II (n = 7); III (n = 4); IV (n = 2), and VI (n = 2). During follow-up after radiosurgical treatment, 11 of 13 patients (85%) were seizure free and off anticonvulsant therapy (mean follow-up 47 months). Two patients had a significant improvement in their seizures but continue on medication. Two of the 72 patients (3%) developed seizures after treatment and remain on medication. Seizure outcome was not associated with the location or complete obliteration of the lesion. We conclude that stereotactic radiosurgery, as a non-invasive alternative, is associated with a good outcome for the AVM as well as AVM-related seizures in children.