Principal Component Analysis of Multimodal Neuromelanin MRI and Dopamine Transporter PET Data Provides a Specific Metric for the Nigral Dopaminergic Neuronal Density
Fig 1
The original PET and MRI metrics.
(a) The averaged radiotracer binding potential to dopamine transporter (BPND) and index for neuromelanin density (RNM) are superimposed on the template T1-weighted image in patients with Parkinson's disease (PD) and healthy controls (HC). The bottom row displays a merged image of BPND and RNM in RGB colour space so that overlapping high intensity regions are yellow. The BPND and RNM pixel intensity was averaged in the substantia nigra region of each subject and shown in (b) and (c), respectively. Overlapping data points are slightly offset horizontally so that all points are visible. The closed circles and error bars indicate the mean and standard deviation for each group. The "*" indicates significant differences between the PD and HC groups (P<0.05).