Fig. 2
From: Advanced abdominal imaging with dual energy CT is feasible without increasing radiation dose
Image noise and contrast-to-noise ratio. Left: The image noise (standard deviation (SD) of CT number) was recorded as the mean measurement of three ROIs placed in the subcutaneous fat of anterior, posterior and lateral abdominal wall (CT fat). Image noise was normalized to CTDIvol by \( SDn=SD\times \sqrt{CDTIvol} \). Right: Mean of CT attenuation of right and left psoas muscle (CTmuscle) was used to calculate the contrast-to-noise ratio (CNRD)