Periinsular hemispherotomy in children with stroke-induced refractory epilepsy

Ischemic cerebral vascular accidents (CVAs) in children result in epilepsy in 25% of patients, which is refractory in 7% of cases. Repeated seizures worsen the global and cognitive prognosis of these patients. To evaluate the prognosis of epilepsy and cognitive development in children with refractory seizures following a CVA, the authors retrospectively studied the effectiveness of periinsular hemispherotomy in the treatment of these patients.

Between March 1995 and November 2007, 8 children who suffered from stroke-induced refractory epilepsy underwent a periinsular hemispherotomy. All patients' charts were reviewed in a retrospective manner. Age at the time of the CVA, imaging studies, cause of the ischemic event, onset of the first seizure, patient's handedness, the extent of the parenchymal damage, electroencephalography findings, type of epileptic seizures, number of seizures per day, number of antiepileptic medications, preoperative neuropsychological evaluation, and surgical outcome with regard to the patient's seizure activity were analyzed.

There were 7 boys and 1 girl in this study. The mean age at stroke was 23 months (range birth-5 years). The mean age at onset of epilepsy was 22 months (range 0-60 months). The mean age at the time of the hemispherotomy was 7 years (range 54-130 months). The average delay prior to the hemispherotomy was 5 years and 3 months (range 23-115 months). Prior to surgery, the average number of seizures per day was 35 (range 5-100). The average number of antiepileptic medications introduced before the hemispherotomy was 8 (range 6-12). Six patients required only 1 surgical intervention and 2 necessitated 2 separate operations:1 underwent a 2-staged hemispherotomy and the other underwent a prior callosotomy. There were no reported surgical complications in this series. Seven children are seizure free. However, the remaining child, after a 3.5-year disease-free interval, has recently started having seizures. No child demonstrated an improvement in neuropsychological evaluation.

The periinsular hemispherotomy must be considered an alternative in the therapeutic approach to stroke-induced pediatric refractory epilepsy. It is effective in controlling seizure activity. The authors believe the delay before hemispherotomy must be shortened in children with post-CVA refractory epilepsy.