Abstracts

Rationale: To describe the effects of deep brain stimulation in two adults with Dravet syndrome (DS) DS is a genetically determined severe epilepsy associated with cognitive decline and ataxia. Diagnosis in childhood has become easier after the isolation of the gene responsible for the majority of cases. Many patients previously diagnosed with vaccination encephalopathy have been demonstrated to have DS. Diagnosis during adulthood is still challenging. The many types of seizures seen in these patients are typically pharmacoresistant. Mortality during childhood is high, mainly due to status epilepticus or sudden unexpected death in epilepsy. Since the seizures are not amenable to resective surgery, deep brain stimulation (DBS) is a possible treatment in this group of patients. Methods: Two adults with genetically proven Dravet syndrome were treated with thalamic DBS targeted to the anterior nucleus of the thalamus and followed for 10 years. No changes in medications were done in the first year after DBS implantation. Subsequent changes in DBS parameters and medications were made in order to obtain better seizure control. Results: One patient with partial onset seizures received DBS at age 19 and showed a marked improvement in seizure control immediately after DBS insertion and stimulation. The other patient with generalized onset seizures received DBS at age 34 and did not show any immediate benefit. Gradual decline in seizure frequency was observed during the 10 year follow-up period. No side effects or changes in cognition were observed in either of the patients. Conclusions: This is the first report of (short and) long term results in Dravet patients treated with thalamic DBS. We speculate that the results of DBS for epilepsy in patients with Dravet syndrome may be related to age at initiation of DBS treatment and seizure type.