Clinical value of MRI, interictal 18F-FDG and 11C-FMZ PET/CT imaging in the diagnosis of hippocampal sclerosing refractory epilepsy

Objective To compare the lateralization accuracy and localization accuracy of MRI, interictal 18F-fluorodeoxyglucose(FDG) and 11C-flumazenil(FMZ) PET/CT imaging for refractory epilepsy(REP) in patients with hippocampal sclerosis(HS). Methods A total of 41 classical HS patients (25 males, 16 females; age: 15-61 years) with REP from General Hospital of Northern Theater Command of PLA between January 2017 and October 2018 were retrospectively analyzed. All patients underwent MRI, interictal 18F-FDG and 11C-FMZ PET/CT imaging, followed by the resection of epileptogenic foci. The pathological diagnosis was taken as the gold standard. Visual and semi-quantitative analyses were used to analyze the images. The lateralization accuracy and localization accuracy of the three imaging methods for epileptogenic foci were calculated and compared(χ2 test). Results The lateral accuracy and localization accuracy of MRI were 70.73%(29/41) and 60.98%(25/41), those of interictal 18F-FDG PET/CT imaging were 78.05%(32/41) and 70.73%(29/41), and those of interictal 11C-FMZ PET/CT imaging were 100%(41/41) and 100%(41/41), respectively. The interictal 11C-FMZ PET/CT imaging was the best among 3 imaging methods(χ2 values: 1.976-12.902, all P<0.01). Conclusions All 3 imaging methods have their advantages and limitations. The interictal 11C-FMZ PET/CT imaging has a high value in the localization of classical HSREP, which can significantly improve the diagnostic accuracy of classical HSREP and guide clinical operation. Key words: Epilepsy, temporal lobe; Sclerosis; Hippocampus; Positron-emission tomography; Tomography, X-ray computed; Flumazenil; Carbon radioisotopes; Deoxyglucose; Magnetic resonance imaging