Post-mortem MRI was performed within 48 h of mortality. Fetal specimens were imaged with T2-weighted 3D sequences and FS-T2 weighted TSE sequences, using a Siemens
Skyra 3.0T system (Siemens Healthineers). A head and neck joint coil was used for the scanning of the thymus. For the T2-weighted 3D sequences, the repetition time was 13.95 msec, echo time was 5.2 msec, the matrix was 512x512, voxel size was 0.4x0.4x0.4 mm and the number of excitations was 2. For the FS-T2-weighted TSE sequences, the repetition time was 6,160 msec, echo time was 60 msec, the matrix was 640x446, the voxel size was 0.3x0.3x1.5 mm and the number of excitations was 4. The scanning time was approximately 20 min. The field of view and the distance factor were adjusted according to the circumference of the chest to produce a signal-to-noise ratio of <1.0.
Yuan L., Cao J., Wang Z., Zhang L., Wang X., Wu Y., Dong J., Xie H, & Lin X. (2020). Fetal thymus in the middle and late trimesters: Morphometry and development using post-mortem 3.0T MRI. Experimental and Therapeutic Medicine, 20(5), 43.