Homogeneous birdcage head coil

MRI studies were performed in a Siemens 3.0 Tesla scanner using a homogeneous birdcage head coil. Subjects lay supine and were required to close their eyes, stay awake and avoid thinking specific thoughts while in the scanner. We used ear plugs and earphones to attenuate scanner noise and a head cushion to reduce head motion. High-resolution 3-dimensional T1WI scans were acquired using a spoiled gradient-echo sequence [repetition time (TR) = 1900 ms, echo time (TE) = 2.48 ms, flip angle (FA) = 90°, field of view (FOV) = 256 mm × 256 mm, acquisition matrix = 256 × 256, slices = 176, section thickness = 1.0 mm]. A gradient-echo-planar imaging sequence was set up to obtain functional images (TR = 2000 ms, TE = 25 ms, 36 slices, section thickness = 4.0 mm, FA = 90°, FOV = 240 mm × 240 mm, acquisition matrix = 64 × 64). Subsequent ASL perfusion MR was performed using a Siemens product pulsed-ASL (pASL) PICORE Q2T sequence (TR = 4000 ms, TE = 12 ms, 27 slices, thickness = 4 mm; FA = 90°; matrix = 64 × 64; FOV = 220 mm × 220 mm).

All subjects underwent the MRI scans at the Affiliated Zhongda Hospital of Southeast University. The subjects were scanned using a Siemens 3.0 Tesla scanner with a homogeneous birdcage head coil. Subjects lay supine with their head snugly fixed by a belt and foam pads to minimize head motion. The MRI acquisition sequences generated 240 volumes in 8 minutes and 176 slices in 4.3 minutes. All subjects were instructed to keep their eyes closed, relax, remain awake and to not think anything specific during scanning.

All subjects underwent the MRI scans at the Affiliated Nanjing Brain Hospital of Nanjing Medical University. The subjects were scanned using a Siemens 3.0 Tesla scanner with a homogeneous birdcage head coil. Subjects lay supine with the head snugly fixed by a belt and foam pads to minimize head motion. A gradient-recalled echo-planar imaging (GRE-EPI) pulse sequence was set up to acquire resting-state images. The acquisition parameters of RS-fMRI were as follows: repetition time = 2000 ms; echo time = 30 ms; flip angle = 90°; acquisition matrix = 64 × 64; field of view = 240 mm² × 240 mm²; thickness = 4.0 mm; gap = 0 mm; 31 axial slices and 3.75 mm² × 3.75 mm² in-plane resolution parallel to the anterior commissure-posterior commissure line. High-resolution T1-weighted axial images covering the whole brain were acquired utilizing a 3-dimensional inversion recovery prepared fast spoiled gradient echo (SPGR) sequence presented as follows: repetition time = 1900 ms; echo time = 2.48 ms; flip angle = 9°; acquisition matrix = 256 × 96; field of view = 250 mm × 200 mm; thickness = 1.0 mm; gap = 0 mm. Those above acquisition sequences generated 140 volumes in 7 min 6 s and 128 slices in 4.3 min, respectively. All subjects were guided to keep their eyes closed and to relax, to remain awake and not to think anything specific during scanning.