Abstracts

Resective surgery of the epileptic focus yields very good results, nevertheless there are cases that escape this surgical possibility, i.e. patients with bilateral hippocampal foci or patients with epileptic focus located nearby eloquent areas for speech and memory (usually the left side). These latter patients cannot be operated on because it would mean having severe neurological impairment particularly related to short term memory. These patients are candidates for neuromodulating procedures. The present study evaluates the long term efficacy of ESH in the treatment of complex partial seizures in patients with intractable mesial temporal lobe epilepsy., Nine patients were studied. They had at least a 6 month basal period during which a careful seizure record was obtained. They all underwent bilateral hippocampal electrode implantation to establish focus was laterality and location. 3 patients had bilateral and 6 had unilateral foci. Diagnostic electrodes were explanted and definitive Medtronic electrodes were implanted directed to the hippocampal foci. Position was confirmed with MRI and afterwards the DBS system internalized. Patients signed the informed consent approved by the Hospital[apos]s Ethics Committee and started a double blind stimulation protocol. Patients attended every 3 months for seizure count and neuropsychological tests., Follow up went from at least 18 months to 5 years. Patients were divided in two groups: 5 had normal MRIs and 4 had hippocampal sclerosis. Patients with normal MRI had a seizure reduction of [gt]95%. Patients with hippocampal sclerosis had a seizure reduction of 30-50%. None of the patients showed deterioration of neuropsychological function, patients who had [gt]95% seizure reduction, showed improvement in the neurophsychological tests. No patient showed adverse effects. 1 patient had to be explanted after 2 years due to skin erosion in the trajectory of the system. 1 patient had skin erosion which was corrected with plastic surgery., ESH provides a non lesional method that improves seizure outcome without deterioration of memory in patients with unilateral or bilateral hippocampal epileptic focus.,