Abstracts

2 groups have demonstrated the safety of Centromedian thalamic stimulation in the treatment of intractable epilepsy. One study showed no significant benefit but the other group demonstrated significant reduction in seizure frequency with this treatment option. We present the experience at our Center with Centromedian Thalamic stimulation in patients with intractable epilepsy. This is a retrospective study of four patients (all Caucasians; age range 7 - 34 years; 2 male, 2 female) who were implanted with Centromedian Thalamic stimulator between August 2001 and November 2003. All of them had intractable epilepsy, had tried a minimum 4 anti-epileptic medications. They had obtained no benefit from vagal nerve stimulator implantation. One patient had partial seizures with secondary generalization. 3 patients had multiple seizure types with multifocal epileptiform discharges. All patients had undergone video-EEG monitoring. DBS Medtronic stimulator was implanted in the Centromedian nuclei by stereotactic method . Initial stimulation parameters were between 50 to 185 Hz, 4.0 to 6.2 volts, 90 ms pulse width, and the stimulation was on for 1 min and off for 4 mins in every 5 min cycles. Stimulation parameters were adjusted in the subsequent clinical visits to control the seizure frequency. Pre-implant baseline seizure frequencies were compared to the seizure frequencies observed on the last follow up clinical visit . Three patients tolerated the procedure well and did not have any cognitive or behavioral side effects during the follow-up period (4 - 31 months). One patient was taken off the stimulator after a period of 19 months due to infection. 3 out of 4 patients showed at least a 50% reduction in seizure frequency on their last clinical visit as compared to their baseline preoperative seizure frequency. After the removal of an infected stimulator the patient had worsening of seizures. Centromedian Thalamic stimulation is a potential therapeutic option available for the treatment of intractable epilepsy, when patients fail to respond to medications, resective surgery and VNS. It appears to be a safe and effective novel method of seizure control in patients with intractable epilepsy in our experience. Our sample size is small and to establish this as an approved form of epilepsy therapy a large randomized multi-center study is needed. Centromedian Thalamic Stimulation - Intractable Epilepsy - Surgery.