Clinical outcome of radiosurgery for cerebral arteriovenous malformations

Abstract
✓ The clinical outcomes are described for 247 consecutive cases of arteriovenous malformation (AVM) treated with the gamma knife between April, 1970, and December 31, 1983. Headache resolved in 65 (66.3%) of the 98 patients presenting with this symptom and improved in an additional nine (9.2%). Of 59 patients admitted with seizures, 11 (18.6%) became seizure-free without anticonvulsant medication and an additional 30 patients (50.8%) became seizure-free with anticonvulsant medication. Pre-existing neurological deficits improved or totally disappeared following radiosurgery in 56.7% of affected cases. This improvement presumably occurred within the frame of the natural history. The protective effect of the ionizing beams against hemorrhage in incompletely obliterated AVM's is analyzed. To assess the rate of rebleeding, probability estimates were calculated using both the person-year method and the Kaplan-Meier life table. With the person-year method the actual rebleed rate is not too different from the val...