Table 2.

Spearman rank correlations between significant regions in the ROI analysis and clinical features or MR indices in the first cohort.

		vs Clinical Features					vs Other Indices
		DD	HY	UPDRS	UMSARS	LEDD	ICVF	FW	FAT	RDT	MVF
White matter
MCP	ICVF	0.1	−0.27	−0.33	−0.11	−0.1	–	−0.54**	–	−0.95**	0.42**
	FW	0.07	0.39	0.3	0.08	−0.06	−0.54**	–	–	0.58**	−0.40**
	RDT	−0.1	0.3	0.37	0.18	0.04	−0.95**	0.58**	–	–	−0.40**
	MVF	0.19	−0.37	−0.47*	−0.2	0.01	0.42**	−0.40**	–	−0.40**	–
ICP	ICVF	0.13	−0.15	−0.36	−0.12	−0.18	–	−0.26**	–	–	0.38**
	FW	−0.12	0.54*	0.38	−0.1	−0.08	−0.26**	–	–	–	−0.49**
	MVF	0.12	−0.4	−0.28	−0.05	−0.17	0.38**	−0.49**	–	–	–
PCT	MVF	0.25	−0.45	−0.52*	−0.27	−0.04	–	–	–	–	–
CST	FW	−0.03	0.33	0.29	0.01	−0.01	–	–	–	–	–
SNc
aSN	ICVF	−0.42	0.22	0.29	0.23	–0.094	–	0.20	0.46*	−0.51*	–
	FW	−0.042	0.0021	−0.30	−0.20	−0.038	0.20	–	−0.33	−0.067	–
	FAT	−0.086	0.39	0.48**	0.38	−0.23	0.46*	−0.33	–	−0.79**	–
	RDT	−0.055	−0.47*	−0.40	−0.36	0.37	−0.51*	−0.067	−0.79**	–	–
pSN	ICVF	0.054	0.39	0.053	0.066	−0.36	–	−0.057	0.65**	−0.83**	–
	FW	−0.051	0.25	−0.20	−0.18	−0.18	−0.057	–	−0.069	0.055	–
	FAT	0.13	0.61**	0.45*	0.36	−0.37	0.65**	−0.069	–	−0.91**	–
	RDT	−0.20	−0.52**	−0.30	−0.25	0.38	−0.83**	0.055	0.91**	–	–

CST corticospinal tract, DD disease duration, FW free water, HY Hoehn & Yahr stage, ICVF intracellular volume fraction, ICP inferior cerebellar peduncle, MCP middle cerebellar peduncle, UPDRS Movement Disorder Society-Unified Parkinson’s Disease Rating Scale part 3, MVF myelin volume fraction, PCT pontine crossing tract, RD_Tfree water-corrected radial diffusivity, SNc substantia nigra pars compacta, UMSARA Unified Multiple System Atrophy Rating Scale part 2.

*FDR corrected P < 0.05; **FDR corrected P < 0.01.