Comparison of Rhenium and Iodine as Contrast Agents in X-Ray Imaging

Table 4

Measurement of the incident air kerma and the mean energy of the X-ray beam.

Scan ID	X-ray tube potential (kVp)	Amount of additional filtration (mm of Cu)	Incident air kerma (Gy)	Mean energy (keV)
X17	50	0	14.9 + 0.1	28.5
X18	50	0.1	10.5	36.2
X19	50	0.3	11.2	39.6
X20	50	0.5	15.4	41.4
X21	50	1	4.2	43.9
X22	50	1.5	1.3	45.1
X23	81	0	49.3 + 0.2	43.1
X24	81	0.1	31.9 + 0.6	48.1
X25	81	0.3	15.4 + 0.1	53.4
X26	81	0.5	12.5	56.5
X27	81	1	9.3	61.0
X28	81	1.5	21.2 + 0.1	63.7
X29	121	0	114.9 + 0.2	53.9
X30	121	0.1	74.0 + 0.2	59.7
X31	121	0.3	46.0 + 0.1	65.9
X32	121	0.5	33.4 + 0.1	69.8
X33	121	1	19.7 + 0.1	76.1
X34	121	1.5	11.7 + 0.1	80.5

The incident air kerma is reported as the mean of three independent measurements. The standard deviation is zero in cases where it is not reported.