We aimed to identify favorable prognostic factors in children undergoing hemispherectomy for intractable epilepsy.

Children with perinatal stroke, malformations of cortical development (MCD), and other cortical structural abnormalities are at increased risk of developing drug-resistant epilepsy. Hemispherectomy is an established surgical option in selected patients.

A retrospective review of our surgery registry was conducted on children <16 years, who underwent functional hemispherectomy (FH) for medically refractory epilepsy at our center between 2010–2024. Multiple clinical variables were reviewed, including etiology, seizure semiology, anti-seizure medication use, neuroimaging, vEEG findings, and Engel outcomes.

Fifteen patients underwent hemispherectomy for stroke (n=4), MCD (n=5), and other etiologies (n=6) (glioma, hemimegaloencephaly, traumatic brain injury, genetic, unknown) [Table 1]. Fourteen patients had pathology confined to a single hemisphere. Mean age of seizure onset was 1.3±0.9 years, epilepsy duration was 3.6±2 years and age at surgery was 5.1±2.3 years. Mean follow-up was 3–5 years. All underwent FH, while two required subsequent anatomic hemispherectomy due to incomplete disconnection.

Twelve patients achieved Engel I, while three had Engel II–IV. Engel I was seen in all MCD (5/5), three stroke (3/4), and four other etiology (4/6) cases. All five stroke patients had MCA stroke, and three achieved Engel I. Ten (of 15) patients had unilateral and five had bilateral/generalized EEG spikes. All three patients with Engel II–IV had bilateral/generalized spikes. Postoperative seizures occurred in five patients (2 from Engel II-IV) within the first week of surgery; three achieved Engel I. Three patients had post-op hydrocephalus (20%), requiring VP shunt. Two patients with MCD underwent consecutive anatomic hemispherectomy.

Functional hemispherectomy appears to provide a high cure rate from intractable seizures in children with unilateral lesions. Neither presence of bilateral epileptiform discharges associated with unilateral pathology nor postoperative seizure was a prognosticator in surgical outcome.