Achieva intera 3 t

A 3.0 T MRI scanner (Achieva Intera 3 T; Philips Healthcare, Best, the Netherlands) was used for image acquisition. T1-weighted anatomical images were acquired using the following parameters: repetition time = 280; echo time = 14 ms; flip angle = 60°; field of view = 24 cm × 24 cm; matrix = 256 × 256; slice thickness = 4 mm. During resting-state scanning, 180 images were acquired with a single-shot, echo-planar pulse sequence (repetition time = 2,000 ms; echo time = 28 ms; slice thickness = 4 mm, no gap; matrix = 64 × 64; field of view = 24 cm × 24 cm; and flip angle = 80°). The participants were instructed to keep their eyes closed comfortably, to stay awake, not to think of anything, and not to sleep or doze off during resting-state scanning. After the scan, all participants were asked whether they had stayed awake with their eyes closed during the entire scanning time. Data from participants who reported difficulties in staying fully awake were discarded and not used for any further analysis.

MRI examinations were performed with a 3-T scanner (Achieva Intera 3T; Philips Healthcare, Quasar Dual, the Netherlands) with an eight-element head coil. Coronal thin-sectional T2-weighted images (for calculation of optic nerve CSA) were acquired with the following imaging parameters: 5701/90 msec (repetition time/echo time), 200 × 200 field of view, and 1.2-mm section thickness with no intersection gap.
A 3-dimensional magnetization-prepared rapid acquisition gradient echo (MPRAGE) structural image was acquired using a T1-weighted magnetization sequence (repetition time [TR], 8.70 ms; echo time [TE], 3.1 ms; 8° flip angle; field of view [FOV], 256 × 256 × 180 mm; and voxel size, 0.7 × 0.7 × 0.7 mm³).