Enhancement of the liver on dynamic MDCT. Investigation among three groups consisting of noncirrhotic patients and cirrhotic patients with and without a large portosystemic shunt

The aim of this study was to determine any difference in hepatic enhancement values on dynamic multidetector row computed tomography (MDCT) among three groups: noncirrhotic patients and cirrhotic patients with and without a large portosystemic shunt. A group of 20 noncirrhotic patients (group A), 43 cirrhotic patients without a large shunt (group B), and 20 cirrhotic patients with a large shunt (group C) underwent dynamic MDCT of the liver using a standard concentration (300 mgI/ml) and volume (100 ml) of contrast material. The attenuation values of the liver were measured during arterial, portal, and late phases. The hepatic enhancement value during the portal phase was significantly higher in group A (56.2±13.7 HU) than in the other two groups (group B 39.8±11.9 HU, group C 41.3±8.3 HU) (P<0.01). No significant difference was present between group B and group C. The regression line of the scattergram, which shows the relation between the hepatic enhancement value during the portal phase and the iodine dose per the patients' body weight was more gently sloping in group C than in the other two groups. In cirrhotic patients without a large shunt, injection of a larger amount of total iodine is necessary to optimize hypovascular tumor visualization. However, in cirrhotic patients with a large shunt, further investigation is needed concerning the effectiveness of administering a larger amount of total iodine. (author)