EPILEPSY SURGERY IN CHILDREN WITH ELECTRICAL STATUS EPILEPTICUS IN SLEEP

OBJECTIVE: Pediatric epilepsy surgery candidates with unilateral congenital or early-acquired brain lesions may present with refractory seizures and generalized electroencephalographic features such as electrical status epilepticus in sleep (ESES). The purpose of our study was to review the clinical presentation, neuroimaging findings, and outcome in a series of children with unilateral brain lesions and ESES undergoing resective surgery for refractory epilepsy. METHODS: A total of 415 consecutive patients younger than 18 years of age undergoing video electroencephalographic evaluation and epilepsy surgery at Cleveland Clinic were reviewed for ESES, an underlying pathological lesion, and outcome after surgery. RESULTS: Eight patients were included. All patients presented with medically refractory epilepsy, hemiparesis, and developmental delay. The pathogenesis was perinatal infarction in 7 patients and malformation of cortical development in I patient. Preoperative electroencephalography demonstrated generalized interictal spikes, electroencephalographic seizures, and ESES in all cases. Age at the time of surgery ranged from 3 to 14 years. Six patients underwent hemispherectomy, and 2 patients underwent focal resection. Six patients became seizure-free after resection. Two patients with functional hemispherectomy continued to have rare seizures, but were much improved. These patients also had perinatal infarctions in the hemisphere contralateral to the resection, possibly indicating a less beneficial outcome. Postoperative electroencephalography demonstrated resolution of generalized interictal discharges and ESES in all. Formal pre- and postoperative neuropsychological testing showed overall improvement of age-equivalent scores. CONCLUSION: Children with unilateral brain lesions and seizures may become seizure-free after epilepsy surgery, even if the preoperative electroencephalogram shows generalized ESES. The lesion occurring early in life and the location of the lesion may play a role in the development of ESES. Cognitive impairment may be aggravated by the persistence of ESES. Preliminary developmental data in this small sample suggest that termination of seizures and possibly of ESES by epilepsy surgery may have developmental benefits.