TABLE 3.

Mean Test–Retest Reliability of the Semiautomated Analyses With the Contrast Ratios From the Voxelwise Analysis and the Volumes From the Semiautomated Thresholding Segmentation

	GRE MT on	TSE MT on	TSE MT off
Threshold analysis
ICC Volume (95% CI)	0.77 (0.31–0.94)	0.71 (0.18–0.92)	0.67 (0.12–0.91)
DSC Volume (SD)	0.91 (0.03)	0.71 (0.07)	0.68 (0.13)
Voxelwise analysis
ICC CRV (95% CI)	0.72 (0.25–0.92)	0.52 (–0.05–0.84)	0.37 (–0.25–0.78)
ICC CRSN (95% CI)	0.90 (0.66–0.97)	0.79 (0.36–0.94)	0.66 (0.09–0.90)
Analysis without spatial smoothing
	GRE MT on	TSE MT on	TSE MT off
Threshold analysis
ICC Volume (95% CI)	0.78 (0.26–0.94)	0.64 (0.07–0.90)	0.65 (0.08–0.90)
DSC Volume (SD)	0.86 (0.03)	0.72 (0.08)	0.51 (0.18)
Voxelwise analysis
ICC CRV (95% CI)	0.63 (–0.00–0.87)	0.38 (–0.21–0.79)	0.26 (–0.34–0.71)
ICC CRSN (95% CI)	0.83 (–0.45–0.95)	0.61 (0.01–0.89)	0.64 (0.06–0.90)

ICC: intraclass correlation coefficient; ICC CR_v: average ICC of voxels in substantia nigra ROI for contrast ratio; ICC CR_sn: ICC for average contrast ratio in the substantia nigra ROI; DSC: Dice similarity coefficient; GRE: gradient recalled echo; MT: magnetization transfer pulse; TSE: turbo spin echo.