Clinical utility of flumazenil PET versus FDG PET and MRI in intractable epilepsy patients: Prospective study with a statistical parametric mapping method

38 Objectives This prospective study assessed the clinical utility of flumazenil PET (FMZ PET) compared with FDG PET and MRI in intractable epilepsy patients. Methods 23 intractable epilepsy patients (M:F=10:13, 30±7 year-old) and 18 normal control sujects (M:F=10:8) were included. FMZ PET, FDG PET and MRI were performed for epileptic focus localization. Confirmation of epileptic focus was based on inpatient video-electroencephalography (EEG). PET was analyzed using a statistical parametric mapping (SPM) method. MRI was analyzed by 2 experienced investigators. Performance of lobar localization of FMZ PET was compared with conventional FDG PET and MRI. Results Video-EEG monitoring confirmed 14 unilateral temporal lobe epilepsy (TLE), 9 neocortical epilepsy. With SPM analysis, 78.3% of FMZ abnormality and 73.9% of FDG abnormality was detected. FMZ PET showed higher detection rate (88.9%) for neocortical epilepsy subgroup compared with FDG PET (55.6%), while detection rate for TLE was slightly lower (71.4%) than FDG PET (85.7%). FDG PET plus MRI wihtout FMZ PET detected 20 of 23 epileptic foci (86.9%). By adding FMZ PET, the rest 3 epileptic foci were detected (100%). All of additionally detected patients were neocortical epilepsy. Conclusions Overall, FMZ PET showed competitive performance with FDG PET. However, higher detecting sensitivity for neocortical epilepsy compared with FDG PET improved detection rate of conventional FDG PET plus MRI protocol, thereby warrant application of FMZ PET to the pre-surgical evaluation of refractory epilepsy