Presurgery Lateralization Of Epileptogenic Focus In Refractory Tle

Objective:To evaluate the values of SPECT brain perfusion imaging in the lateralization of the epileptic foci in unilateral temporal lobe epilepsy (TLE).Methods:we assessed 57 patients with pathologically proven unilateral TLE Their pathology, EEG, MRI, interictal SPECT and PET results were compared for accuracy in locating the epileptic foci. The images of SPECT were analyzed using region of interest (ROI) in temporal lobes and asymmetry index (AI) was calculated. Correlative analysis of AI and clinical factors was performed.Results:1. The sensitivity of interictal SPECT in the lateralization of the epileptogenic focus in unilateral temporal lobe epilepsy patients was 70.2%(40/57), which was similar to the sensitivity of MRI (73.7%) and EEG (78.9%).2. Interictal SPECT correctly lateralizied 5 of 7 patients incorrectly lateralizied by EEG, and lateralizied 6 of 9 patients incorrectly lateralizied by MRI. Interictal SPECT lateralizied 11 patients in 20 patients whose results of MRI and EEG were discordant.4. Among the 57 TLE patients, the sensitivity of interictal SPECT in lateralization of epileptogenic focus in tonic dystonic seizure groups, complex partial seizure, and complex partial seizure secondary tonic dystonic seizure was 100%,60%and 66.7%respectively. 5. Intetictal SPECT correctly identified the epileptogenic zone in 5 (45.4%) of 11 focal cortical dysplasia (FCD) patients, which was lower than other methods.6. In 29 patients with correct SPECT lateralization proved by pathological results, AI was correlated with seizure subtypes, and may guide the surgery about the selection of focal cortex burn with electric ambipolar.Conclusions:Interictal SPECT is helpful in localization and laterlization of epileptogenic zones in unilateral TLE patients, especially in patients with ambiguous MRI or EEG results.