Dynamic Alterations of Tongue in Sleep Apnoea Hypopnea Syndrome During Sleep

MRI was performed with a 1.5 superconducting magnet (Gyroscan Intera type, Philips Co. Holland) in a posterior and anterior neck coil. The sequence used to perform the ultrafast MRI was a fast gradient- echo plus sequence. Technical parameters included: echo time, 12 msec; repetition time, 2.3 msec; flap angle, 250; matrix, 192 × 512; section thickness, 7 mm. The imaging time per slice for this sequence was 0.92 sec. A total of 120 consecutive images were obtained as a single section, with a total imaging time of 110.4 seconds. MRI scanning was carried out with the subject first asleep, then whilst awake after 20 minutes in quiet respiration. All images were inputted to the PACS workstation.