Effect of The Body Water and The Body Composition, Calculated by Bioelectrical Impedance Analysis, On Contrast-Enhanced Dynamic Computed Tomography Images of The Liver.

<jats:title>Abstract</jats:title> <jats:p>To improve its diagnosis on contrast-enhanced dynamic CT (CE-DCT) scans, contrast injection protocol must yield stable arterial contrast enhancement. To investigate how the body-water distribution and the body composition, calculated by bioelectrical impedance analysis (BIA), affect aortic and hepatic enhancement on CE-DCT scans. 236 patients with liver cirrhosis underwent CE-DCT before BIA. The CT number (in Hounsfield units, HU) of the abdominal aorta at the celiac artery level on unenhanced scans and during the hepatic arterial phase (HAP) scans was recorded. And, the mean CT number of the hepatic parenchyma of both hepatic lobes at the celiac artery level on unenhanced and portal venous phase (PVP) scans was recorded. We calculated changes in the iodine dose per contrast enhancement (mgI/HU) (IDCE) to evaluate the effect of the patient age and of various constituents of the body composition by performing BIA. The IDCE of the abdominal aorta during HAP was 121.5 ± 32.1 mgI/HU; it was 698.7 ± 211.1 mgI/HU in the hepatic parenchyma during the PVP. Among the parameters used in our BIA, the total body weight (TBW) was the most important factor affecting the IDCE of the liver abdominal aorta on CE-DCT scans acquired during the HAP (r = 0.83). The TBW and the skeletal muscle index most strongly affected the IDCE of the hepatic parenchyma on CE-DCT scans obtained during the PVP (r = 0.69). The TBW had the strongest effect on contrast enhancement. The skeletal muscle index exhibited the strongest correlation with hepatic parenchymal contrast enhancement during the PVP.</jats:p>