Table 2:

Results of ROI measurements

Group		80 kV	100 kV	120 kV	Study Group Complete	Control Group (120 kV)
n		18	24	10	53	45
ROI carotid	Mean	488.4 ± 93.3a	340.9 ± 73.8a	243 ± 83.2a	372.5 ± 122.1a	293.9 ± 58
	SD	12.7 ± 2.8a	12.1 ± 2.7a	7.9 ± 3.1	11.5 ± 3.3a	8.8 ± 1.8
	SNR	40.1 ± 12.3	29.9 ± 9.4	33.7 ± 13	34.1 ± 11.8	35.2 ± 11.7
	CNR	34.9 ± 11.5a	24.4 ± 8.9	25 ± 12.7	28.1 ± 11.5	28.3 ± 10.9
ROI muscle	Mean	61.4 ± 7.8	62.2 ± 11.2	61.4 ± 9.8	61.8 ± 9.7	58.9 ± 6.3
	SD	9.7 ± 2.7a	9.6 ± 2.8a	6.5 ± 2.4	9.1 ± 2.9a	6.7 ± 1.4
ROI air	Mean	−1000.2 ± 1.8a	−999.1 ± 2.2	−999.2 ± 1.3	−999.5 ± 2	−998.7 ± 2.2
	SD	6.2 ± 1.9a	6.5 ± 2.2a	4.1 ± 1.3	5.9 ± 2.1	4.6 ± 1

Note:—Values correspond to Hounsfield units.

^aP < .05.