Clinical and radiological impact of liver transplantation for brain in cirrhosis patients without hepatic encephalopathy

Objective To elucidate the effect of liver transplantation (LT) on brain dysfunctions in cirrhotic patients who had no clinical evidence of hepatic encephalopathy (HE), we performed a prospective study of voxel-based diffusion tensor imaging (DTI) and detailed cognitive examination. Methods We assessed 12 consecutive patients as transplant candidates by DTI, with neurological and cognitive examinations just before and at 6 months after LT. Results After LT, cirrhotic patients showed significant improvement in visual reproduction, digit symbol, digit span, Stroop test, and Trail-making test scores, suggesting recovery of frontal-temporal function. As for voxel-based DTI, increased mean diffusivity (MD) and reduced fractional anisotropy (FA) values were found before LT in the frontal and temporal lobes of cirrhotic patients. After LT, the unusual FA and MD values observed in the frontal and temporal lobes preoperatively were significantly reduced. Conclusion End-stage cirrhotic patients without clinical evidence of HE showed increased MD and decreased FA values in both frontal and temporal lobes. These parameters improved after LT, in line with cognitive function. MD and FA values might be of value as a biomarker in end-stage cirrhotic patients for investigating brain tissue dysfunctions and evaluating the efficacy of LT.