Pattern approach to MR imaging in patients with end-stage hepatic failure: a proposal for a new disease entity “hepatic encephalopathy continuum”

Abstract

The purpose of this study was to evaluate the clinical features and the characteristics of MR images of patients with end-stage hepatic failure. We reviewed the MR findings and clinical features of 31 consecutive patients (20 men, 11 women=31, mean age 58.7 years) who had been diagnosed with clinical hepatic encephalopathy. Associations between the lesion locations on each MR sequence were analyzed using a binominal test. The clinical and MR findings were compared in relation to the etiology and clinical status. The most frequently involved site, seen as high signal intensity on T2-W images, was the corpus callosum (20 patients), followed by the dentate nucleus (16 patients) and the globus pallidus (13 patients). Significant associations were seen between the pallidus and the crus cerebri, between the crus cerebri and the red nucleus, between the crus cerebri and the dentate nucleus, and between the red nucleus and the dentate nucleus on the T2-W and DW images (P < 0.004). The crus cerebri, red nucleus, and dentate nucleus were involved concurrently with the corpus callosum more frequently in hepatic encephalopathy grades 3 and 4. Concurrent involvement of the globus pallidus-crus cerebri-red nucleus-dentate nucleus axis was the main MR pattern in end-stage hepatic encephalopathy, which connected with various areas of the brain. We hypothesize that these overlapping MR features could be regarded as an entity denoted as the "hepatic encephalopathy continuum".