Abstracts

Rationale: Rationale; Deep brain stimulation (DBS) is used to treat a number of different illnesses and it has been used in epilepsy using different targets such as hippocampus, the centromedian nucleii of the thalamus, the cerebellum and the anterior nucleii of the thalamus (ANT) in order to treat both generalized and focal epilepsies.We have studied 18 patients treated with DBS for epilepsy from 2010 to 2015Methods: Method; In the study protocol 40 patients were originally planned to be included. 18 patients (11 women, 7 men) with refractory epilepsy were operated with bilateral electrodes to the ANT. The study has a prospective, randomized, double blinded, controlled design. The first six months after the operation was blinded with regard to stimulation on or off. At six months the code was broken and the patients that had not received active stimulation got their stimulator turned on. All patients were followed the first year after the operation according to the study protocol. Three months prior to the operation and during the study period, all medication was kept unchanged and the patients were asked to keep a thorough seizure diary. Both prior to the operation and one year after the operation all patients went through a thorough neuropsycological and psychiatric evaluation, and a minor evaluation at six months postoperatively. At every control in the study period LSSS (Liverpool seizure severity scale) and Qual-89 were filled outResults: Results; After one year of follow-up the results were as follows; Effect on seizure frequency; -one patient had become seizure free, -two patients had experienced a 25 to 30% reduction in seizure frequency -12 patients experienced no effect. - two patients got worse with active stimulation in the sense that they got back GTC and increased numbers of seizures The results from the last patient operated in March 2015 is not available Complications in relation the operation; - one patient experienced a temporary central paralysis to the left n.facialis Side effects of the stimulation; -one patient felt every sixth minute an incredible happiness and desire to express this happiness to other people lasting for a minute. This feeling was replaced with an empty, sad feeling that lasted the next five minutes. -one woman, when the stimulator was turned on, experienced fear and anxiety with a different set of thoughts that made her afraid that she would hurt her children -other side effects of the stimulation was; diplopia, vertigo, reduced memory, a prickling sensation in the head every time the DBS started. Three of the patients have their stimulators turned off due to intolerable side effects .Conclusions: Conclusion: Deep brain stimulation given to the ANT in this prospective, randomized, double blinded, controlled clinical trial was disappointing both regarding to lack of effect on seizure frequency and intolerable side effects. Because of that, the study was stopped.