Subtotal hemispherotomy for intractable lesional hemispheric epilepsy without hemiparesis in children

Purpose We analyzed the surgical indications, outcomes, and prognostic factors of subtotal hemispherotomy for intractable lesional hemispheric epilepsy in children with almost normal motor function and summarized its surgical strategies. Methods We retrospectively analyzed 20 children who underwent subtotal hemispherotomy (hemispheric disconnection sparing sensorimotor cortex) between March 2015 and May 2021. The children were divided into seizure-free group and residual seizures group according to their surgical outcomes. The surgical outcome was based on International League Against Epilepsy (ILAE) classification (class 1–6). All presurgical evaluation data were collected and analyzed. Results Among the 20 children, the mean age at the time of seizure onset, mean age at the time of surgery, and mean follow-up time was 3.2 ± 2.8, 7.5 ± 4.4, and 3.5 ± 2.1 years, respectively. All children had hemispheric lesion on MRI. At the last follow-up evaluation, 75% (15/20) of children remained seizure-free. Univariate analyses revealed that the electrocorticogram finding of epileptiform discharges in the central cortex after disconnection were poor prognostic factors for seizure outcomes (P < 0.05). Disconnection of the central operculum and insula was a poor prognostic factor for motor function after surgery (P < 0.05). Conclusions For intractable lesional hemispheric epilepsy with no hemiparesis, subtotal hemispherotomy can be performed with favorable seizure outcome. Disconnection of the central operculum and insula may increase the possibility of motor function injury.