Visualization of nigrosomes-1 in 3T MR susceptibility weighted imaging and its absence in diagnosing Parkinson's disease.

OBJECTIVE: To assess the imaging features of nigrosomes-1 in the substantia nigra through 3T MR susceptibility weighted imaging (SWI) and its disease-specific changes for the diagnosis of Parkinson's disease (PD). PATIENTS AND METHODS: A total of 116 subjects were included in this study and allocated into 3 groups: 54 patients diagnosed with PD were assigned to the PD group, 51 age- and sex-matched volunteers without PD served as the control N-PD group, and 11 clinically suspected PD patients were allocated to the undiagnosed (UD) group. All patients received 3.0T superconducting MRI scanning on xxx. The images were analyzed and compared to assess the ability of nigrosomes-1 signals to depict PD pathology. RESULTS: The signals of nigrosomes-1 were strong, droplet-like or oval in shape, and were found in 49 patients from the N-PD group (96.08%), on both sides of the SN (47 cases) and unilaterally (2 cases). In contrast, these signals were absent in all 54 cases from the PD group, and were undetected in 7 out of 11 cases in the UD group, 7 cases without the "drop" and 1 case with narrow strips of hyperintensity were clinically proven to PD, 2 cases with the typical hyperintensity were clinically proven to Parkinson's plus syndrome, 2 cases with slightly wider strip of hyperintensity were less sensitive to the drug levodopa. CONCLUSIONS: The absence of typical droplet-like or oval-shaped nigrosomes-1 signals in 3.0T MR SWI may prove useful in identifying PD and Parkinson's syndrome with high sensitivity and specificity.