Evolution of epileptic seizures associated with cerebral arteriovenous malformations after radiosurgery

The goal of this study is to evaluate the response of epileptic seizures as sociated with cerebral arteriovenous malformations following radiosurgery a nd determine tire factors associated with a positive outcome. The series included 210 patients (123 men, 87 women) with a mean age of 33. One hundred seventy three patients out of 210 were controlled after radiosu rgery. Seizures completely disappeared in 58% of cases and decreased in 18% . Antiepileptic-treatment was stopped in 44%. Sex and age upon seizure appe arance were not found as determining factors in patients whose seizures dis appeared after radiosurgery. Generalized seizures disappeared Sal lowing ra diosurgery in 90.7%, partial secondary generalized seizures in 53.5%, and p artial seizures in only 39.6%. Frontal or temporal malformations are associ ated with a better response after radiosurgery than sylvian or rolandic loc ation Seizure disappearance was maximal in case of isolated seizure prior t o the radiosurgery (84.4%), was reduced to 61.2% when seizures were limited To 2 to 20, and disappeared in 21.4% in severe seizures: Epilepsy present less than 3 years prior to radiosurgery disappeared in 71.9%; was reduced t o 45% when the delay was over 3 years. Seizures oblitera-peared in 64.4% wh en the malformation was obliterated, they were reduced to 46.9% when malfor mations persisted The persistence of severe seizures following radiosurgery was linked to persistence of the malformation. On the other hand early sei zures occurred in 3.3% during the first 48 hours following radiosurgery; th ey disappeared in 72.2% after that period. De novo seizures also occurred i n 1.7% and disappeared in all these cases. In conclusion, seizures associated with cerebral arteriovenous malformation s respond well to radiosurgery; the malformation obliteration evokes its as sociation with the seizure; the seizure disappearance in spite of persisten ce of the malformation evokes the positive effect of radiotherapy on epilep tic seizures.