Abstract Details

Title Deep Brain Stimulation in Hemimegalencephaly with Medically Intractable Epilepsy: A Case Report

Topic Epilepsy/Clinical Neurophysiology (EEG)

Presentation(s) P5 - Poster Session 5 (11:45 AM-12:45 PM)

Poster/Presentation
Number 9-010

Background

Hemimegalencephaly is a rare congenital disorder with overgrowth of a partial or entire cerebral hemisphere. This is seen in approximately 0.2% of childhood epilepsy and often leads to refractory seizures. In medically intractable cases, a hemispherectomy is considered to remove the epileptogenic focus.

Objective

To highlight a unique case of medically intractable epilepsy secondary to hemimegalencephaly responsive to deep brain stimulation (DBS).

Design/Methods

Case report.

Results A 22-year-old right handed male presented with medically intractable focal epilepsy secondary to right hemimegalencephaly. He developed convulsive seizures with gustatory auras at 9 years old. He had a normal birth history, but delayed cognitive impairment. Initial MRI brain was read as normal, however his pediatric neurologist noted right hemimegalencephaly and he was trialed on anti-seizure medications (ASM). This included levetiracetam, oxcarbazepine, valproic acid, clobazam, and lacosamide with initial response; however, efficacy waned over time. He later had focal seizures with impaired awareness and generalized tonic-clonic seizures. He was admitted to the epilepsy monitoring unit and a focal epilepsy with right fronto-central focus was observed. Repeat MRI brain and PET scan in 2018 revealed a right hemimegalencephaly that on further review traced back to imaging from 2009. Genetic testing was unrevealing. Seizures remained medically intractable and a vagus nerve stimulation (VNS) device was implanted with failed seizure control. He subsequently underwent DBS with bilateral lead placements in the anterior nucleus of the thalamus (ANT). In combination with ASMs, he reported a 60-70% seizure reduction.

Conclusions

Hemimegalencephaly can occur in isolation or in association with syndromes such as tuberous sclerosis, Klippel-Trenaunay, or neurofibromatosis. While there is no cure, the goal is to reduce seizures with ASMs or hemispherectomy in refractive pediatric cases. Given the absence of motor deficits, hemispherectomy was not considered. This is a novel case of DBS being utilized in the management of hemimegalencephaly.

Authors/Disclosures
Delini Sivakumar, MD (Prisma Health) PRESENTER	Dr. Sivakumar has nothing to disclose.
Nada Ahmed, MD (Prisma Health)	Dr. Ahmed has nothing to disclose.
Andrea S. Hakimi, DO (Prisma Health-Upstate/USC-Greenville)	Dr. Hakimi has nothing to disclose.