Quantitative Color Mapping of the Arterial Enhancement Fraction in Patients With Diffuse Liver Disease

OBJECTIVE. The purpose of this study was to determine whether color mapping of the arterial enhancement fraction of the liver with multiphasic liver CT can depict the hemodynamic changes associated with diffuse liver disease. MATERIALS AND METHODS. A total of 142 patients (59 men, 83 women; mean age, 50 years) with diffuse liver disease and 25 patients acting as controls (11 men, 14 women; mean age, 54 years) were classified into three groups: controls (n = 25), patients with acute liver injury (no underlying chronic liver disease [n = 25], acute exacerbation of chronic liver disease [n = 17]), and patients with chronic hepatic injury (hepatitis [n = 25]; cirrhosis [n = 75], 25 each with Child-Pugh A, B, and C disease). The quantitative arterial enhancement fraction color map of the liver was generated from routine multiphasic CT images with prototype software. The mean arterial enhancement fractions of each group were compared by analysis of variance. The correlation between arterial enhancement fraction and Child-Pugh grade was evaluated with Spearman correlation. The area under the receiver operating characteristic curve for arterial enhancement fraction in the detection of acute liver injury and noncompensated chronic liver disease was calculated. RESULTS. The mean arterial enhancement fractions of the liver in each group were significantly different (p < 0.0001, analysis of variance): control, 28.5%; acute liver injury without underlying chronic liver disease, 51.1%; acute exacerbation of chronic liver disease, 42.0%; chronic hepatitis, 25.4%; Child-Pugh A disease, 23.7%; Child-Pugh B disease, 32.2%; Child-Pugh C disease, 43.4%. Arterial enhancement fraction correlated with Child-Pugh grade (Spearman rho = 0.553, p < 0.0001). The areas under the curve of arterial enhancement fraction in the detection of acute liver injury and noncompensated chronic liver disease were 0.96 and 0.78. CONCLUSION. With color mapping of the arterial enhancement fraction derived from multiphasic liver CT scans, it is possible to visualize the hemodynamic changes associated with the severity of cirrhosis and acute liver injury.