Postoperative outcomes and predictors of functional sequelae following hemispheric surgery in Rasmussen's encephalitis: A retrospective cohort study from the global pediatric epilepsy surgery registry.

OBJECTIVE: Rasmussen's encephalitis (RE) is a rare and progressive, immune-mediated epileptic encephalopathy characterized by drug-resistant seizures and neurological decline. While hemispheric disconnection (HD) is the gold standard treatment for effective seizure control, this procedure carries significant risk of permanent neurological sequelae. Systematic evaluation of both seizure and functional outcomes is essential to guide surgical decision-making. METHODS: We conducted a retrospective cohort study using caregiver survey data from the Global Pediatric Epilepsy Surgery Registry. Children with RE who underwent HD and had complete postoperative data were included (n = 37). The primary outcome was to examine pre and postoperative functional status, including seizure freedom, motor and mobility changes, visual impairments, language difficulties, operative complications, and caregiver-reported quality of life (QoL) and regret. Multivariable analysis was run on candidate predictors (seizure onset, age at surgery, hemisphere of surgery, seizure frequency, number of surgeries, hydrocephalus). RESULTS: Mean age at seizure onset was under 6 years, with mean age at surgery 8.4 years and mean time to surgery 3.6 years. Postoperatively, 84.8% achieved seizure freedom, which correlated with QoL improvement (p = .008). Hemiparesis increased from 22% to 97%; 35.8% lost the ability to run, 6.1% to walk, 6.4% to stand, and 31.2% to roll unassisted. Visual deficits rose from 16% to 84.4%. Left-sided surgery predicted language deficits (p = .019), while older age at surgery was associated with increased loss of motor milestones (p = .016). Hydrocephalus occurred in 18.2%. Overall, 86% of caregivers reported QoL improvement; 54.8% wished surgery had been performed earlier, and 12.5% expressed regret. SIGNIFICANCE: HD in pediatric RE yields high rates of seizure freedom and caregiver-perceived QoL improvement but carries substantial risks of motor, language, and visual sequelae. These findings emphasize the importance of individualized, patient-centered counseling and support the need for prospective studies to refine prognostic models and inform surgical decision-making.