Contrast Medium Volume Optimization in Abdominal CT on Basis of Lean Body Weight

Abstract

Computed tomography (CT) in abdominal imaging has undergone great advances in recent years. The administration of iodinated contrast media (CM) has evolved along with the evolution of the CT equipment. The most common method for calculation of the CM volume in abdominal CT is based on total body weight (TBW), but in this way some patients get a lower dose and some other patients get a higher dose that the optimal dose they need. In the literature there are many formulas to calculate the CM volume to be administered in abdominal CT, but practice shows that the variability of enhancement is wide. The main objective of this study is to verify that the volume of intravenous CM in abdominal CT calculated on basis of lean body weight (LBW) allows good liver enhancement with small amplitude of variation around the mean, that is, with less variability in enhancement than CM volume calculated on basis of TBW. In conclusion the calculation of the volume of CM on basis of LBW translates into a low variability of liver enhancement–25.50 HU. In our results 96.05% of sample belongs to a good hepatic enhancement. If we stratify sample by groups of BMI, we also verify no significative differences between slims and fat patients when analysed mean hepatic enhancement.