Table 1 Quantitative analysis of image sets (conventional images and VME images 40–120 KeV) according to CNR

Conventional

6.63 ± 4.92

40 KeV

18.47 ± 12.98

< 0.001^*

50 KeV

13.55 ± 9.41

< 0.001^*

< 0.001^*

60 KeV

10.36 ± 7.18

< 0.001^*

< 0.001^*

70 KeV

8.24 ± 5.56

< 0.001^*

< 0.001^*

80 KeV

7.17 ± 5.18

0.004^*

< 0.001^*

90 KeV

6.31 ± 4.63

0.051

< 0.001^*

100 KeV

5.76 ± 4.33

< 0.001^*

< 0.001^*

110 KeV

5.14 ± 3.68

< 0.001^*

< 0.001^*

120 KeV

5.07 ± 3.97

< 0.001^*

< 0.001^*

^Frp

< 0.001^*