Seizure outcome of pediatric epilepsy surgery: Systematic review and meta-analyses

This systematic review and meta-analyses assessed seizure outcome following pediatric epilepsy surgery.

MEDLINE, EMBASE, and Cochrane were searched for pediatric epilepsy surgery original research from 1990 to 2017. The outcome was seizure freedom at 12 months or longer follow-up. Using random-effects models, the effect sizes for controlled studies, uncontrolled studies on surgery locations (temporal lobe [TL], extratemporal lobe [ETL], or hemispheric surgery), pathologies, nonlesional epilepsy, and incomplete resection were estimated. Meta-regression assessed the relationship between age at surgery, age at seizure onset, and seizure outcome. Random-effects network meta-analysis was conducted for surgery locations.

Two hundred fifty-eight studies were included. Surgery achieved higher seizure freedom than medical therapy (odds ratio [OR] = 6.49 [95% confidence interval [CI]: 2.87-14.70], p < 0.001). Seizure freedom declined over time after surgery, from 64.8% (95% CI: 51.2%-76.4%; p = 0.034) at 1 year, to 60.3% (95% CI: 52.9%-67.4%; p = 0.007) at 5 years, and to 39.7% (95% CI: 28.4%-52.2%, p = 0.106) at 10 years. Seizure freedom was (1) highest for hemispheric surgery, followed by TL and ETL surgery, and (2) highest for tumor and lower for malformations of cortical development. Seizure freedom was lower for nonlesional than lesional epilepsy (OR = 0.54 [95% CI: 0.34, 0.88], p = 0.013) and incomplete than complete resection (OR = 0.13 [95% CI: 0.08, 0.21], p < 0.001). Age at surgery and age at seizure onset were associated with seizure freedom for mixed pathologies and surgery locations and TL surgery.

Epilepsy surgery was more effective than medical therapy to control seizures. Understanding seizure outcomes of different surgery locations, pathologies, nonlesional epilepsy, and incomplete resection will assist with presurgical counseling.