Abstracts

Rationale: Experimental and clinical studies have suggested that electrical deep brain stimulation (DBS) of subcortical structures is a promising therapy for patients with refractory epilepsy over the last decade. Bilateral stimulation of the anterior nuclei (AN) of the thalamus is useful for some patients with medically refractory partial seizure, while the efficacy of bilateral centromedian (CM) nucleus stimulation in generalized forms of epilepsy has been recently identified. We report on the outcome after thalamic AN and CM DBS in five patients with medically refractory seizures. Methods: Four patients with medically refractory partial and generalized seizures and one patient with continuous spike wave status (CSWS) during sleep were studied. All patients were either not candidates for resective surgery or refractory to the treatment of vagus nerve stimulation and/or resection surgery. All cases underwent bilateral AN and CM thalamic DBS. In order to optimize the DBS programming for seizure management, three patients were admitted to the Epilepsy Monitoring Unit (EMU) for quantification of seizures after DBS implantation and additional DBS programming based on their EEG recording results. Results: Post-operative MRI documented that all electrodes were correctly located. There was no morbidity or mortality. The average seizure frequency reduction in the four epilepsy patients was 63 percent (range 50 - 80%). EEG revealed that the spike-wave index was decreased from 90% to 50% in the patient with CSWS. Increased attention level was seen in all patients. Additionally, cognition and mood were stable or improved in all cases. Conclusions: These findings suggest that Bilateral stimulation of the AN and CM of the thalamus reduces seizures. DBS programming based on EEG recording results is useful for seizure management.