ABSTRACT
OBJECTIVE: The provisional diagnosis of progressive supranuclear palsy (PSP) depends on a combination of typical clinical features and specific MRI findings, such as atrophy of the tegmentum in the midbrain. Atrophy of the superior cerebellar peduncle (SCP) distinguishes PSP from other types of parkinsonism. Histological factors affect the conventional fluid-attenuated inversion recovery (FLAIR) signals, such as the extent of neuronal loss and gliosis. METHODS: We investigated patients with PSP to verify the percentage of patients with various PSP phenotypes presenting a high signal intensity in the SCP. Three interviewers, who were not informed about the clinical data, visually inspected the presence or absence of a high signal intensity in the SCP on the FLAIR images. We measured the pixel value in the SCP of each patient. Clinical characteristics were evaluated using the Mann-Whitney test, followed by the χ² test. RESULTS: Ten of the 51 patients with PSP showed a high signal intensity in the SCP on FLAIR MRI. Higher pixel values were observed within the SCP of patients with a high signal intensity in the SCP than in patients without a high signal intensity (p < 0.001). The sensitivity and specificity of the high signal intensity in the SCP of patients with PSP was 19.6% and 100%, respectively. This finding was more frequently observed in patients with PSP with Richardson's syndrome (PSP-RS) (25.7%) than other phenotypes (6.2%). CONCLUSION: The high signal intensity in the SCP on FLAIR MRI might be an effective diagnostic tool for PSP-RS.
Subject(s)
Humans , Atrophy , Diagnosis , Gliosis , Magnetic Resonance Imaging , Mesencephalon , Neurodegenerative Diseases , Neurons , Parkinsonian Disorders , Phenotype , Sensitivity and Specificity , Supranuclear Palsy, ProgressiveABSTRACT
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.