Diagnostic accuracy for the epileptogenic zone detection in focal epilepsy could be higher in FDG-PET/MRI than in FDG-PET/CT

Objectives To examine the utility of FDG-PET/MRI in patients with epilepsy by comparing the diagnostic accuracy of PET/MRI and PET/CT in epileptogenic zone (EZ) detection. Methods This prospective study included 31 patients (17 males, 14 females) who underwent surgical resection for EZ. All patients were first scanned using FDG-PET/CT followed immediately with FDG-PET/MRI. Two series of PETplusstandalone MR images were interpreted independently by five board-certified radiologists. A 4-point visual score was used to assess image quality. Sensitivities and visual scores from both PETs and standalone MRI were compared using the McNemar test with Bonferroni correction and Dunn's multiple comparisons test. Results The EZs were confirmed histopathologically via resection as hippocampal sclerosis (n = 11, 35.5%), gliosis (n = 8, 25.8%), focal cortical dysplasia (n = 6, 19.4%), and brain tumours (n = 6, 19.4%) including cavernous haemangioma (n = 3), dysembryoplastic neuroepithelial tumour (n = 1), ganglioglioma (n = 1), and polymorphous low-grade neuroepithelial tumour of the young (n = 1). The sensitivity of FDG-PET/MRI was significantly higher than that of FDG-PET/CT and standalone MRI (FDG-PET/MRI vs. FDG-PET/CT vs. standalone MRI; 77.4-90.3% vs. 58.1-64.5% vs. 45.2-80.6%,p < 0.0001, respectively). The visual scores derived from FDG-PET/MRI were significantly higher than those of FDG-PET/CT, as well as standalone MRI (2.8 +/- 1.2 vs. 2.0 +/- 1.1 vs. 2.1 +/- 1.2,p < 0.0001, respectively). Compared to FDG-PET/CT, FDG-PET/MRI increased the visual score (51.9%, increased visual scores of 2 and 3). Conclusions The diagnostic accuracy for the EZ detection in focal epilepsy could be higher in FDG-PET/MRI than in FDG-PET/CT.

Automated summary

The study demonstrated that FDG-PET/MRI had higher sensitivity and visual scores compared to FDG-PET/CT and standalone MRI in patients with epilepsy, leading to improved diagnostic accuracy in detecting the epileptogenic zone (EZ). EZs were histopathologically confirmed through surgical resection, with common pathologies including hippocampal sclerosis, gliosis, focal cortical dysplasia, and brain tumors. FDG-PET/MRI showed significant improvement over FDG-PET/CT and standalone MRI, increasing visual scores and enhancing detection of EZs.