Neurosurgical management of childhood-onset epilepsy in periventricular nodular heterotopia: A systematic review of effectiveness and outcomes.
TL;DR
Minimally invasive ablation appears effective and safe, while neuromodulation offers palliation where curative treatment is not feasible, and Invasive EEG-guided approaches can achieve seizure freedom in around half of children with PVNH-related epilepsy, with outcomes strongly predicted by laterality.
Abstract
Epilepsy associated with periventricular nodular heterotopia (PVNH) frequently begins in childhood and often proves refractory to medication. Surgical management is challenging, as lesions are frequently deep-seated or bilateral, and seizure onset often involves networks extending beyond the heterotopic tissue itself, with the precise contribution of the nodules varying between patients. This systematic review synthesises all available evidence on neurosurgical and invasive interventions for childhood-onset PVNH-associated epilepsy, focusing on outcomes and prognostic factors. We conducted a PRISMA 2020-compliant systematic review searching PubMed/MEDLINE, Scopus, and Web of Science from inception to 13 December 2025. Eligible studies reported neurosurgical interventions in patients with MRI- or histopathology-confirmed PVNH whose epilepsy began before age 18, with outcomes reported using Engel or ILAE classification. Two reviewers independently screened and extracted data. Methodological quality was appraised using GRADE. Findings were synthesised narratively due to the inherent heterogeneity of the included studies. Thirty studies comprising 134 patients met our inclusion criteria. Excellent outcomes, defined as seizure freedom or auras only, were achieved in 50.7% (n = 68), with 76.9% (n = 103) experiencing meaningful benefit, defined as at least a 50% reduction in seizure frequency. Outcomes were better in unilateral than bilateral PVNH (75.9%vs 33.8%, p < 0.001) and with complete rather than incomplete nodule removal (72.9%vs 25.0%, p < 0.001). Permanent morbidity was 10.4% (n = 14), predominantly visual field deficits. Invasive EEG-guided approaches can achieve seizure freedom in around half of children with PVNH-related epilepsy, with outcomes strongly predicted by laterality. As with all subgroup comparisons in this review, reported p-values reflect effect size across pooled retrospective cohorts rather than formal hypothesis testing. Minimally invasive ablation appears effective and safe, while neuromodulation offers palliation where curative treatment is not feasible. Evidence remains limited by retrospective study designs and small sample sizes, and prospective multicentre data are needed.