TABLE 2.

Percent coefficient of variation cυ of tissue intensities in segmented GM and WM regions for twelve simulated MRI scenes before correction, and after correction by N3 and SBC methods.

			cυ(GM)			cυ(WM)
Date Set	Protocol	Inhomogeneity	Original	N3	SBC	Original	N3	SBC
D6 (normal)	T1	20%	11.0	9.9	9.9	6.7	5.1	5.1
		40%	13.5	10.0	9.9	9.2	5.2	5.2
	T2	20%	18.4	18.0	17.9	12.0	11.8	11.7
		40%	20.3	20.0	17.9	13.3	13.0	11.8
	PD	20%	6.3	4.6	4.5	5.5	4.7	4.7
		40%	9.7	4.6	4.5	7.5	4.6	4.6
D6 (lesions)	T1	20%	11.2	10.1	10.1	6.9	5.3	5.3
		40%	13.7	10.2	10.1	9.3	5.3	5.4
	T2	20%	10.9	10.0	9.8	8.7	8.3	8.1
		40%	13.7	10.1	9.8	10.6	8.2	8.2
	PD	20%	5.8	3.9	3.8	5.3	4.4	4.3
		40%	9.4	4.0	3.9	7.4	4.3	4.3