Interictal brain SPECT in patients with medically refractory temporal lobe epilepsy

The objective of this study was to evaluate the utility of interictal brain SPECT in localizing the epileptogenic focus in a population of patients of Epilepsy Clinic of Hospital Universitario Clementino Fraga Filho (HUCFF/UFRJ), with medically refractory temporal lobe epilepsy (TLE) and normal computed tomography (CT) scans, studying the correlation between SPECT, electroencephalogram (EEG) and, in 11 cases, brain magnectic resonance imaging (MRI), and to compare the results to the other six literatura series. Twelve (52.2%) patients presented abnormal SPECT. Among these, five (41.6% of abnormal SPECTs) presented unilateral SPECT changes at the same side of EEG (hypoperfusion in four and hyperperfusion in one), three (25% of abnormal SPECTs) presented bilateral hypoperfusion and bilateral EEG changes too, and four (33.3%) presented unilateral hypoperfusion and bilateral EEG changes. The statistical analysis was based on fuzzy logic. The correlation index among SPECT X EEG, SPECT X MRI and SPECT X EEG X MRI were highly significant, with significance levels at 0.01, p < 0.0005 and trust interval at 99% in all correlations. The correlation studies between the series presented similar results.