PURPOSE: To investigate the differences in signal changes in the globus pallidus and white matter, as seen on T1-weighted MR brain images, and to determine whether these differences can be used as an indicator of subclinical hepatic encephalopathy. MATERIALS AND METHODS: A total of 25 cases of liver cirrhosis were evaluated.and as a control group, 20 subjects were also studied. Using a 1.5T MRI scannet, brain MR images were btained, and the differences in signal intensity in both the globus pallidus and thalamus and in both white and gray matter were then quantified using the contrast to noise ratio(CNR). On the basis of the Child-Pugh classification, 25 patients with liver cirrhosis were divided into three groups, with eight in group A, eight in B, and nine in C. Using clinical criteria, hepatic encephalopathywas diagnosed in seven of the 25 patients. Thereafter, CNRs(CNR1 and CNR2) were conpared between the control and cirrhotic groups and between cirrhotic groups with or without hepatic encephalopathy. RESULTS: In the control group, mean values were 3.2 +/-5.9 for CNR1 and 8.4 +/-8.0 for CNR2. In the cirrhotic group, these values were 10.6 +/-9.0 for CNR1 and 9.8 +/-6.4 for CNR2. A statistically significant difference was noted between normal and cirrhotic groups only for CNR1(p < 0.05). CNR values in patients with liver cirrhosis were 8.5 +/-11.5 for CNR1 and 11.7 +/-8.7 for CNR2 in the Child A group, 10.4 +/-5.1 for CNR1 and 9.3 +/-3 . 2 for CNR2 in the B group, and 12.8 +/-9.7 for CNR1 and 8.7 +/-6.5 for CNR2 in the C group. There was no significant difference in mean CNRI values between patients with or without hepatic encephalopathy. CONCLUSION: Differences in signal intensities in the globus pallidus and white matter, as seen on T1-weighted MR brain images, cannot be used as an indicator of hepatic encephalopathy in patients with liver cirrhosis.