Quantitative evaluation of magnetic resonance imaging (MRI) abnormalities in subclinical hepatic encephalopathy

Cirrhotic patients often demonstrate high signal intensity on T1-weighted magnetic resonance (MRI) images in basal ganglia with accumulation of manganese being the predominant causing factor. In these patients, electrophysiological tests and especially electroencephalogram (EEG) are considered to be the most sensitive methods in detection of subclinical hepatic encephalopathy. The aim of this study is to correlate MRI findings with biochemical parameters and EEG alterations in cirrhotic patients without clinically overt encephalopathy.

Twenty-two cirrhotic patients (16 males and 6 females, mean age of 65.2 +/- 9.5 years), classified according to Child-Pugh score, were submitted to brain MRI, neurological assessment (including psychometric tests and EEG) and complete biochemical testing. None of them had any clinical signs of brain dysfunction. MRI findings were evaluated both qualitatively (normal, mild, moderate and severe) and quantitatively with the ROI method. EEG alterations were also classified as normal, mild, moderate and severe.

Statistical analysis revealed a significant linear association between EEG grading and MRI signal intensity (r2=0.248, p=0.035). Among clinical and biochemical parameters, overall Child-Pugh score and albumin levels were identified as significant predictors of the MRI signal intensity (p=0.006 and p=0.021 respectively).

Although further investigation must be performed to confirm the clinical impact of brain MRI in hepatic cirrhosis, our study strongly suggests that MRI alterations are good predictors of liver and brain dysfunction in cirrhotic patients.