Appearances of decussation of superior cerebellar peduncle in DTT FACT with different reconstruct parameters / 中国医学影像技术

ABSTRACT

Objective To observe the appearances of decussation of superior cerebellar peduncle (SCP) on MR diffusion tensor imaging (DTI) with different parameters of scanning and reconstruction. Methods Twenty healthy volunteers were examined on Siemens 3.0T MR DTI (b=0, 1000 s/mm~2), post processing were made in Siemens Leonardo workstation using Siemens Standar 6 dirs software to reconstruct the white matter fibers with different fractional anisotropy (FA) threshold value (0.04-0.20), angle threshold value (20°-89°) and voxel size (1.2 mm×1.2 mm×3.0 mm-1.6 mm×1.6 mm×5.0 mm). Results Crossing fiber was presented each voxel group on diffusion tensor tractography (DTT). The types of crossing fiber in the small voxel were more than those of big voxel image obviously. Reduced along with the FA threshold value, the number of crossing fiber increased gradually. After the peak value (FA=0.08), the number of crossing fiber reduced along with the FA threshold value reduced gradually. Increased along with the angle threshold value, the number of crossing fiber increased gradually. The number of crossing fiber reduced along with the angle threshold value increased gradually after the peak value (the angle threshold value＝80°). There were 5 kinds of MR fiber tracking appearances at the level of decussation of SCP on DTT. The fiber crossed to the opposited red nucleus in anterior-posterior style, superior-inferior style and single main bundle fiber. Kissing fiber and missing fiber sign was shouw in all subjects, which mainly located in the center of the decussation. Conclusion DTT FACT can show the descussation of SCP in most health subjects with five typical appearance. The descussation of SCP has the obvious appearances, may be causing by individual difference. For the crossing fiber of SCP, voxel size 1.2 mm×1.2 mm×3.0 mm, FA 0.08 and the angle 80° are recommended.