Table 2.

Rules used to set up the priors for the intensity model. Self refers to the modal intensity inside the structure that is to be segmented. The image intensities for the QSM volumes are not image-based because of the quantitative nature of the modality. No units are shown as the values have not been scaled to physical units and are treated as arbitrary units instead.

Structure	Modality	Type	Inside	Outside
Substantia nigra	T2⁎	Exponential (1 and 3 mm)	Self	Self × 1.33
Exponential (1 mm)	Self	Self × 0.67
QSM	Exponential (1 and 2 mm)	0.15	0.05
Subthalamic nucleus	T2⁎	Exponential (1 and 3 mm)	Self	Self × 1.2
Exponential (1 mm)	Self	Self × 0.5
QSM	Step	0.1	0.0
Exponential (1 and 3 mm)	0.1	0.0
Red nucleus	T2⁎	Exponential (1 and 3 mm)	Self	Self × 1.33
QSM	Exponential (1 and 3 mm)	0.1	0.0