Abstracts

To evaluate the utility of [123I]iomazenil(IMZ)-SPECT in finding seizure foci in childhood epilepsy, we applied IMZ-SPECT to the patients with intractable localization-related epilepsy who were in considering surgical treatment., In evaluation of IMZ-SPECT images, [apos]iSSP35[apos] and [apos]Focus Viewer[apos] (Nihon Medi-Physics Co., Ltd.)that were developed to asses the IMZ-SPECT data conveniently by using asymmetry index(AI) mapping, were utilized to compare the distribution of signal levels between right and left hemisphere. We studied 11 patients (frontal lobe epilepsy(FLE); 4, temporal lobe epilepsy(TLE); 2, malignant rolandic epilepsy; 4, parietal lobe epilepsy; 1), and the results were compared with those of ECD-SPECT, FDG-PET, EEG, MEG, and MRI. On MRI study, hippocampal sclerosis was observed in two with TLE, focal cortical dysplasia or polymicrogyria was observed in 1 with FLE and 2 with malignant rolandic epilepsy, and posttraumatic atrophic legion was noted in 1 with FLE., Abnormal signal area in AI map was detected in 6 out of 11 patients(54%) on the same region that was suspected as a seizure focus by other multi-modal imaging technique, EEG and seizure semiology. Two patients with TLE had clear abnormal signal on the temporal region, however, there was no recognizable signal abnormality in 4 patients with malignant rolandic epilepsy. MEG was done in 8 patients and localized dipole was estimated in 6 patients (75%). Especially, MEG clearly detected seizure foci in all patients with malignant rolandic epilepsy. FDG-PET was done in 9 patients, 6 (67%) of which showed localized legion with hypometabolism. Among them, 2 with TLE had clear legion with hypometabolism, while 3 of 4 with malignant rolandic epilepsy showed no abnormalities. Interictal ECD-SPECT was done in 6 patients, two (33%) of which showed localized hypoperfusion., Although this is a preliminary study with limited patient number, localizing power of IMZ-SPECT seemed to be next to FDG-PET. Seizure foci in malignant rolandic epilepsy were poorly detected by IMZ-SPECT and FDG-PET as compared to MEG. More patients are needed for drawing a conclusion on the efficacy of IMZ-SPECT.,