Ex vivo magnetic resonance imaging of pretransplant human donor liver. Clinical experience in 66 cases.

Magnetic resonance imaging (MRI) was performed on 66 cold-stored human donor livers. Spin echo images were obtained with a clinical whole body MRI system. Various parenchymal and vascular abnormalities were found. An unexpected finding was the abundant presence of intrahepatic air. Although the majority of parenchymal abnormalities that were found would not have precluded transplantation, the rationale of pretransplant MRI was to prevent the introduction of unidentified pathology into the recipient. Guided by the MR images, lesions in the isolated organ can be easily located for biopsy and resection. Unnecessary or inadequate therapeutic interventions after transplantation can thus be avoided. In addition, the visualization of the hepatic veins with their confluence appears to be useful in split-liver procedures.

The tissue hydration state in UW-preserved human donor livers. A clinical study of the relation between proton magnetic resonance relaxation times, donor condition, preservation procedure, and early graft function.

To determine the relation between tissue hydration state--as indicated by tissue proton magnetic resonance relaxation times--in UW-preserved human donor livers and viability parameters of the donor and early graft function, "ex vivo" magnetic resonance relaxometry was performed with a clinical MR imaging system. Relaxometric data were obtained from MR images in which signal intensities were directly proportional to T1 and T2. Forty-three subsequently transplanted livers and five discarded livers were studied. The donor serum concentrations of direct and total bilirubin had a positive correlation with T1 (P < 0.05 and P < 0.01, respectively). Sequential measurements in 7 livers demonstrated a firm time relation between the cold storage time and the length of the relaxation times. As cold storage time lengthened, T1 and T2 shortened. T1 of the donor liver showed a significant negative correlation with recipient ASAT and ALAT values on days 1, 2, and 3 after transplantation. T1 in the discarded group was significantly higher than T1 in the accepted group. T2 was not different in the two groups. It is concluded that in UW-preserved human donor livers, the tissue hydration state, as indicated by the tissue MR relaxation times, is largely independent of the clinical condition of the organ donor and the preservation procedure. An optimum tissue hydration state, in UW-preserved donors liver might have protective properties against parenchymal damage, although the clinical consequences appear to be of minor importance. The capacity of relaxometry as a discriminative instrument to accept or to discard donor livers is poor.