Quantitative MRI of liver grafts for assessment of macrovesicular steatosis ex vivo and long-term follow-up outcomes

Objective To indicate whether ex vivo magnetic resonance imaging (MRI)-proton density fat fraction (PDFF) could be advantageous for selection of liver grafts and to achieve information about pre-transplant indicators of the quality of liver grafts. Materials and methods MRI-PDFF was performed using a 3.0 T scanner. Totally, 35 liver grafts were pathologically confirmed and 19 liver grafts were used for liver transplantation. Surgeon established a grading system for cadaveric livers based on visual inspection of liver color. The grades ranged from normal (score 3) to mild/moderate (score 2) to severe (score 1). One region of interest (ROI) was selected in each of the liver I-VIII segments. The Pearson or Spearman correlation coefficient was used to analyze the correlation according to the distribution of data. MRI-PDFF and histological findings of grafts obtained before implantation ex vivo, together with the graft survival rate and incidence of early allograft dysfunction (EAD), were analyzed. The Kaplan–Meier method was used to calculate graft survival rates, and log-rank test was utilized to compare them. Results The average of nine-ROI PDFF in the cohort was 4.1 ± 4.4%. The macrovesicular steatosis group had higher MRI-PDFF value than the normal group, with statistical significance ( P