INTRACTABLE TEMPORAL-LOBE EPILEPSY - COMPARISON OF POSITRON EMISSION TOMOGRAPHY WITH QUALITATIVE AND QUANTITATIVE MR

PURPOSE: To compare the ability of qualitative fludeoxyglucose F 18 po sitron emission tomography (QPET), qualitative MR imaging (QMR), and q uantitative MR imaging with hippocampal formation volumetric assessmen t (HV MR) to lateralize the seizure focus in patients with temporal lo be epilepsy. METHODS: Sixteen consecutive patients undergoing presurgi cal examination for temporal lobe seizures had QPET, QMR, and HV MR, T he presence of temporal lobe epilepsy was confirmed by Engel class I o r II outcomes at 1-year postoperative follow-up examinations. A QPET, QMR, or HV MR study was considered to be lateralizing if it matched th e side of the seizure focus, nonlateralizing if it did not lateralize the seizure focus to either temporal lobe, or incorrectly lateralizing if it lateralized the seizure focus to the incorrect side. RESULTS: O f 16 patients with proved temporal lobe seizures, QPET was correctly l ateralizing in nine (56%), nonlateralizing in six (37.5%), and incorre ctly lateralizing in one (6%). QMR was correctly lateralizing in six ( 37.5%), nonlateralizing in six (37.5%), and incorrectly lateralizing i n four (25%). HV MR was correctly lateralizing in all 16 patients (100 %). Age at onset, seizure duration, and total number of seizures did n ot correlate with QPET, QMR, and HV MR lateralization. CONCLUSIONS: Ou r results show that each imaging technique yields useful information f or seizure lateralization in temporal lobe epilepsy and that HV MR yie lds considerably more information than QPET or QMR.