Regulation of Blood-Brain Barrier Permeability by APOE Gene Polymorphism and Its Impact on Cognitive Function Post-Radiotherapy in Nasopharyngeal Carcinoma: an MRI Study

"1. Resting-state fMRI:~ Use the Gradient Echo Echo Planar Imaging (GRE-EPI) sequence with the following parameters: repetition time (TR) = 2000 ms, echo time (TE) = 30 ms, flip angle (FA) = 90°, slice thickness = 3.0 mm, slice spacing = 0.8 mm, field of view (FOV) = 240 mm × 240 mm, matrix = 128 × 128, in-plane resolution = 64 × 64, 39 axial slices scanned, 240 dynamic scans.~2. DSI:~ Use diffusion-sensitive imaging (DSI) with 64 diffusion directions, b-values of 0 and 1000 s/mm², TR = 3000 ms, TE = 64 ms, number of excitations (NEX) = 1, matrix = 112 × 112, FOV = 224 mm × 224 mm, slice thickness = 2 mm, no spacing between slices, full brain coverage, and 75 slices scanned.~3. Three-dimensional brain structural MRI:~Sagittal data acquisition is performed with the following parameters: TR = 8.16 ms, TE = 3.18 ms, inversion time (TI) = 800 ms, flip angle (FA) = 8°, matrix = 256 × 256, FOV = 256 mm × 256 mm, voxel size = 1 mm × 1 mm × 1 mm, and 176 slices scanned."