Evaluation of lnterictal Tc-99m ECD SPECT in Adults With Medical Refractory Epilepsy

Abstract

Background. Accurate detection and localization of epileptic focus are very important, especially for presurgical evaluation. However, both magnetic resonance imaging (MRI) and electroencephalography (EEG) have limitations. Regional cerebral blood flow single photon emission computed tomography (SPECT) has proven to be a valuable method for detecting epileptic focus. The purpose of this study was to evaluate the clinical value of interictal Tc-99m ethyl cysteinate dimer (ECD) SPECT for detecting epileptic focus in adults with medical refractory epilepsy. Methods. We performed interictal Tc-99m ECD brain SPECT on54 adults (28 men and 26 women; age range: 21 to 45yr) with a history of medical refractory epilepsy. Twenty-six patients presented with generalized tonic clonic seizure (GTCS), 27 with complex partial seizure (CPS) and one with both conditions (GTCS + CPS). Eight of the 27 patients with CPS underwent epilepic surgery on the basis of the preoperative Tc-99m ECD brain SPECT results. Results. Interictai Tc-99m ECD brain SPECT showed areas of hypoperfusion in 18 of 26 patients with GTCS (69%), in 23 of 27 patients with CPS (85%) and in one patient with both GTCS and CPS. The condition of eight patients with CPS improved greatly after epileptic surgery. Conclusions. lnterictal Tc-99m ECD brain SPECT is a useful and accurate imaging modality for the detection and localization of epileptic focus in adults with medical refractory epilepsy.