Relationship Between Liver Function and Liver Signal Intensity in Hepatobiliary Phase of Gadolinium Ethoxybenzyl Diethylenetriamine Pentaacetic Acid-Enhanced Magnetic Resonance Imaging

Objective: To evaluate the effect of liver function on liver signal intensity in gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging in humans and to examine the biochemical factors related to signal intensity in the hepatobiliary phase. Methods: This study included 48 patients with suspected hepatocellular carcinoma or metachronous liver metastases from colorectal cancer. The patients were divided into 2 groups: the chronic liver dysfunction and the normal liver function. All the individuals of both groups had magnetic resonance imaging before injection and at 5, 10, 15, 20, 25, and 30 minutes after bolus administration of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid. The time point when the mean liver signal-to-noise ratio (SNR) reached a peak was determined for each group, and the mean liver SNR at the peak point was compared between the groups. In all the patients, stepwise multivariate analysis was used to evaluate the relationship between the liver SNR at the peak time point and the laboratory data, using the following biochemical factors: prothrombin time, total bilirubin level, cholinesterase level, albumin level, creatinine level, indocyanine green retention rate at 15 minutes, and Child-Pugh score. Results: The mean values of liver SNR increased gradually. The mean liver SNR reached peak at 30 minutes after contrast injection in both groups and was significantly lower in the chronic liver dysfunction group than in the normal liver function group. Indocyanine green retention rate at 15 minutes was the only significant contributor to the liver signal intensity at the peak time point (30 minutes). Conclusions: The degree of liver enhancement in the hepatobiliary phase may reflect liver cell function. The measurement of liver signal intensity in the hepatobiliary phase may be useful in predicting whole and regional hepatic functional reserves.