Table 1.

The calculated Hounsfield units for bone

Diagnostic group	Bone tissue	Electron density [g/cm3]	Calculated HU (age)
HN	Skeleton-cranium (whole)	1.61 (adult)	971
Prostate	Skeleton-femur (whole)	1.33 (30 years)	349 (66.8 years*)
		1.22 (90 years)
Pelvic	Skeleton-femur (whole)	1.33 (30 years)	356 (64.7 years*)
		1.22 (90 years)
Vesica	Skeleton-femur (whole)	1.33 (30 years)	309 (78.8 years*)
		1.22 (90 years)

The bone HUs are calculated based on generic electron densities from ICRU Report 46 [16] and a parameterization of our CT calibration curve from ICRU Report 42 [17]. *The average age in the diagnostic group.