Introduction: Dravet syndrome (DS), also known as severe myoclonic epilepsy of infancy, is a rare syndrome carrying a poor prognosis. DS results from mutations of the neuronal sodium ion channel gene SCN1A. DS presents at about 1 year of age with seizures that are often associated with fevers. As patients age, seizures occur without fevers and multiple seizure types develop. There are few reports and no guidelines regarding surgical treatment for DS. Here, we present our institution’s experience with surgical treatment of DS that is the largest published to date.

Methods: We conducted a retrospective review of all patients with genetically confirmed DS who underwent either vagal nerve stimulator (VNS) implantation or corpus callosotomy (CC)) from August 1999 to January 2014 at our institution. All inpatient and outpatient relevant documentation was reviewed. Demographic information, SCN1A mutation, operation performed, and preoperative and postoperative seizure frequency were recorded. Inclusion criteria required 1 year postoperative follow up.

Results: Eleven surgeries were performed on eight patients during the study period. Five VNS and three CC were performed in seven patients that met inclusion criteria. At least one year elapsed from presentation to our hospital and surgery for all patients. Average time to surgery was 4.3 years. The mean age of patients undergoing CC was 8.4 years compared to 6.0 years for those undergoing VNS implantation. Seizures were decreased in all patients after each procedure and CC was more effective than VNS for seizure control.

Conclusions: Both VNS and CC in patients with DS can be effective at reducing seizure frequency and improving quality of life. Patients with DS may benefit from earlier and more aggressive surgical intervention. Further studies will help determine the optimal time and type of surgical intervention.

Patient Care: Improve understanding of Dravet syndrome and lead to earlier diagnosis and better utilization of surgical treatments for this syndrome.

Learning Objectives: - Identify the cause and natural history of Dravet syndrome - Discuss surgical and non-surgical treatments for Dravet syndrome

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