~(18)F-FDG PET, EEG and MRI examinations in the localization of epileptic foci before operation: a comparative study

Objective To evaluate the diagnostic value of interparoxysmal examinations with 18F-FDG positron emission tomography (PET), electroencephalography (EEG) and magnetic resonance imaging (MRI) in the localization of epileptic foci before operation. Methods Preoperative 18F-FDG PET, EEG and MRI examinations were performed in 24 patients with refractory epilepsy, who also received electrocorticography (ECoG) during the operation. All the examination results including that of postoperative pathological examination of the excised tissues were compared to decide their diagnostic values. Results Interparoxysmal 18F-FDG PET imaging displayed the epileptic foci in 23 patients, and the rates of positive findings by EEG and MRI were 83.3% and 16.7% respectively. With PET examination, the localization of the epileptic foci was confirmed by ECoG at a rate up to 83.3%, while the rate was 41.7% with EEG. In cases that EEG and PET results were both positive, the rates reached 100%. Conclusions 18F-FDG PET imaging is sensitive and effective in epileptic foci detection and localization with much superiority over EEG and MRI, and it may assist in designing the surgical protocol for refractory epilepsy.