Introduction: Medically-refractory epilepsy complicates management of congenital hemispheric overgrowth, frequently requiring hemispherotomy. We describe two infants with hemispheric overgrowth and intractable epilepsy who underwent serial endovascular embolization as part of comprehensive epilepsy management. With this treatment, invasive surgery is delayed to allow somatic growth to reduce surgical morbidity. This approach has been reported, but results have not yet been replicated.

Methods: Patient 1 has left hemimegalencephaly due to an AKT3 mutation. Patient 2 has a large right parieto-occipital cortical malformation due to an NPRL3 mutation. Both patients had ongoing clinical seizures despite anti-seizure polypharmacy, including Sirolimus and Vigabatrin. Patient 1 underwent five embolization procedures by age six months. Patient 2 underwent two embolization procedures by age seven months. Considerations of preoperative, intraoperative, and postoperative continuous EEG as well as postoperative neuroimaging is provided.

Results: Intraoperative super-selective arterial embolizations and intended ischemic evolution were well tolerated. Patient 1’s seizures remain refractory, but clinical seizure stabilization following embolizations reduced requirement for IV medications and allowed discharge home. Further embolizations and likely hemispherotomy will occur in the coming months when somatic growth is optimal. In Patient 2, embolizations led to seizure stabilization and ultimate reduction in anti-seizure medications. Additional embolizations may be necessary. Both patients remain on anti-seizure polypharmacy.

Conclusion: Rarity of these conditions would require national or international networks to accumulate sufficient patient numbers to make statistically significant conclusions. However, endovascular embolization shows promise for palliative reduction of clinical seizure burden and reduced hospitalization while awaiting more traditional surgical intervention.

Disclosures: None.

Catherine Brown
Cincinnati Children's Hospital Medical Center
United States

Hansel Greiner
Cincinnati Children's Hospital Medical Center
United States

James Leach
Cincinnati Children's Hospital Medical Center
United States

Francesco Mangano
Cincinnati Children's Hospital Medical Center
United States

Jesse Skoch
Cincinnati Children's Hospital Medical Center
United States

Cameron Thomas
Cincinnati Children's Hospital Medical Center
United States

Kishore Vedala
Cincinnati Children's Hospital Medical Center
United States

Sudhakar Vadivelu
Cincinnati Children's Hospital Medical Center
United States