Abstracts

RATIONALE: The purpose of this paper is to define the general efficacy and morbidity of SEEG using modern methods of image and particularize risks related to specific lobes of the brain. METHODS: All patients admitted at MNI, who underwent either CT or MRI guided electrode implantation by one surgeon (A.O.), were reviewed. Procedure was considered efficient if the obtained information was satisfactory to make a decision for or against surgery. RESULTS: 217 patients underwent 224 implantations with 3022 electrodes. Complications related to specific regions: temporal lobe, 2 abscesses (0.54%); frontal lobe, 1 abscess and 3 hematomas (1.4%); occipital lobe, 1 hypointense lesion was found 1 month after implantation (2,6%). Hematomas occurred in frontal lobes with 4 or more implanted electrodes (P<0.025), cerebral atrophy was present in all these cases. General complications: 26 patients presented psychiatric symptoms during monitoring, 1 case of meningitis, 4 of scalp cellulites and 2 of hemiparesis during angiography in early 1980s, 1of them kept a mild hemiparesis and represents the only case of permanent sequela in the entire series. Data obtained during recordings supported indication for surgery in 178 patients (79.5%), excluded a surgical option in 37 patients (16.5%), and were not satisfactory in 9 cases (4.0%). Thus, overall efficacy was 96.0%. CONCLUSIONS: SEEG is an efficient procedure with low morbidity. Bilateral exploration of the temporal lobes has morbidity around 1 percent. Higher risk of hematomas is found in frontal lobes with 4 or more implanted electrodes. Cerebral atrophy also seems to increase risk of bleeding.