Table 1.

Comparison of measured and calculated Hounsfield look-up table points

	CT scanner 1			CT scanner 2
	HU	WEPL	ΔWEPL	HU	WEPL	ΔWEPL
fat	-73.9 ± 20.8	0.978	-0.1 %	-97.9 ± 45.6	0.978	-2.6 %
	-72.7 ± 21.2	0.978	-0.0 %	-109.3 ± 43.6	0.960	-1.9 %
	-73.9 ± 27.6	0.980	-0.3 %	-102.6 ± 44.4	0.972	-2.5 %
brain	45.0 ± 17.4	1.044	-0.0 %	47.4 ± 16.0	1.042	0.3 %
	40.9 ± 15.0	1.054	-1.1 %	38.7 ± 18.6	1.041	-0.0 %
	44.0 ± 16.4	1.040	0.4 %
kidney	53.1 ± 26.9	1.046	-0.0 %	49.0 ± 20.7	1.048	-0.2 %
	66.0 ± 15.8	1.041	2.1 %	54.0 ± 15.6	1.048	0.1 %
	57.5 ± 26.6	1.045	0.7 %
liver	83.3 ± 20.5	1.059	0.8 %	75.5 ± 20.1	1.063	0.3 %
	79.7 ± 19.0	1.059	0.7 %	74.4 ± 27.6	1.064	0.2 %
	81.3 ± 13.7	1.061	0.6 %	72.9 ± 21.3	1.064	0.2 %
leg	65.5 ± 18.8	1.053	1.0 %
	66.9 ± 23.6	1.072	-0.7 %
	65.4 ± 19.6	1.049	1.3 %
neck	66.0 ± 25.8	1.036	2.6 %
	50.0 ± 47.5	1.043	0.4 %
filet	73.3 ± 16.2	1.049	1.6 %
	63.6 ± 25.5	1.049	1.1 %
	69.5 ± 22.6	1.049	1.6 %

HLUT measurements with two different CT scanners for fat, brain, kidney, and liver and additional measurements for various muscle tissues with CT scanner 1. Different samples of the same tissue type were used for measurements with CT scanner 1 and 2. To compare with measured data, relative differences in water equivalence in comparison to predictions based on the current HLUT are presented, positive numbers would result in over-ranges and negative values in under-ranges.