Abstracts

RATIONALE: The physiology of the mesial parietal cortex is not well studied in man. Parietal refractory epilepsies are rare and the surgical results described in the earlier series are very poor. This paper reports on the surgical results in patients with refractory epilepsy submitted to mesial parietal resections. METHODS: Nine refractory epileptic patients submitted to resection of the mesial parietal cortex (MPC)were studied. Four were submitted to a resection of the MPC alone (Group I) and in 5 there were additional cortical resections (Group II). All group I patients were submitted to left side resections. Four Group II patients were operated on the right and 1 on the left side. Mean age at surgery was 17 years (3-28); mean seizure frequency was 2x/week (1-10) and mean follow-up time was 22 months (3-48). RESULTS: Pathological examination showed cortical dysplasia (n=2), DNET (n=1) and neurocisticercosis (n=1) in Group I patients and gliosis (n=4) and oligodendroglioma (n=1) in group II patients. Three Group I and 4 Group II patients have been seizure-free since surgery. The other 2 patients are in Engel's class II (1 with cortical dysplasia and 1 with gliosis). Except for a Group II patient left with a permanent grade IV (V=normal) hemiparesis, there were no other surgical morbidity related to the resection of MPC. CONCLUSIONS: MPC resections may be highly effective in selected patients. The extention of the posterior quadrant resection needed to render the patients seizure-free is usually larger than the one needed in temporal lobe epilepsy. Special attention should be paid to the Trolard's venous complex. The grade IV hemiparesis in our Group II patient was due to postoperative trombosis of the vein of Trolard.