Functional hemispherectomy for seizure control in encephalocraniocutaneous lipomatosis: illustrative case.

backgroundEncephalocraniocutaneous lipomatosis (ECCL) is a rare neurocutaneous syndrome composed of a spectrum of congenital cutaneous, ocular, and brain anomalies. Principal anomalies include nevus psiloliparus lesions of the scalp, ocular choristomas consisting of dermolipomas, and intracranial lipomas and arachnoid cysts. The hypothesized pathogenic basis in ECCL is a developmental mesenchymal defect involving neural crest cell derivatives. Management is typically focused on treating symptoms, directed at the organ system and supportive neurorehabilitation. Reports to date have only focused on pharmacotherapeutic treatment of drug-refractory epilepsy (DRE), a principal neurological phenotype. Surgical management of medication-refractory epilepsy, which can occur in up to 70% of ECCL subjects, has not been described to date. OBSERVATIONS: The authors present an illustrative case report of a 4-year-old girl with ECCL who developed DRE and underwent a functional hemispherectomy for seizure relief. The clinical course, diagnostic evaluation, and surgical treatment are described, with emphasis on surgical-pathological observations. LESSONS: To the authors' knowledge, surgical treatment for hemispheric onset DRE in the context of ECCL has not been reported. Systemic and clinical features on presentation are reviewed to highlight aberrant mesenchymal differentiation as the developmental basis for the syndrome. The authors also underscore the role of functional hemispherectomy in the treatment of DRE in the context of a genetic/developmental syndrome. https://thejns.org/doi/10.3171/CASE2578.