FUNCTIONAL NEUROSURGERY IN THE TREATMENT OF EPILEPSY IN THE NETHERLANDS - ASPECTS OF PRESURGICAL EVALUATION AND THE CONTRIBUTION OF SUBDURAL AND STEREOTAXICALLY IMPLANTED DEPTH ELECTRODES IN THE DUTCH WORKGROUP FOR FUNCTIONAL SURGERY

In the Netherlands all patients who are considered candidates for surg ical treatment of their epilepsy are referred to the Dutch Workgroup f or Functional Neurosurgery. Resective neurosurgery in partial epilepsy is a focus of special interest of national health authorities. Annual ly 15-20 patients can now be operated upon. Presurgical evaluation inc ludes a.o. 18/FDG PET. For depth-EEG recording a specially designed me thod of ''Combined Subdural and Depth-EEG Recording'' is used which ha s been described previously. 70 patients underwent depth-EEG recording with the combined method. In 4.2% of the patients there were transien t complications, in 1.4% there was a possibly permanent slight neurolo gical deficit caused by the method. Fiftysix patients were evaluated a t least one year after their surgical treatment (median follow-up 3 ye ars). In the frontal lobe group comprising 9 patients 56% were seizure -free, 76% benefited from the treatment. In the temporal lobe group wi th 47 patients 68% were seizure-free and 92% benefited. No patient det eriorated from the resection. Permanent morbidity was nil.