Congestion Area of the Right Lobe Graft in Living Donor Liver Transplantation: Quantitative Evaluation of Hemodynamics Using Computed Tomography Perfusion

Background. The hemodynamics of congestion areas in the right lobe graft after living donor liver transplantation (LDLT) remains unclear. The aim of this study was to elucidate the hemodynamics of congestion areas in the right lobe graft after LDLT using computed tomography (CT) perfusion imaging and the dual-input maximum slope method. Methods. Sixteen recipients underwent CT perfusion of the liver and portal phase abdominal to pelvic CT 1week after LDLT using a right lobe graft. The attenuation of segments V and VIII on the portal venous phase abdominal to the pelvic CT scan was classified into 3 categories: hyperattenuation, iso-attenuation, and hypoattenuation. Mean arterial blood flow (AF, mL/min/ 100 mL tissue), portal blood flow (PF, mL/min/100 mL tissue), and perfusion index (%) [PI = AF/(AF + PF) pound 100] were compared between the hyperattenuation group and iso-attenuation group. The independent t test was used for these statistical analyses. Results. On the portal phase abdominal scan, 15 segments, 16 segments, and 1 segment showed hyperattenuation, iso-attenuation, and hypoattenuation, respectively. The mean AF and PI of the hyperattenuation group (44.4 +/- 24.4, 30.2 +/- 13.5) were significantly higher than those of the iso-attenuation group (28.0 +/- 7.8, 19.9 +/- 6.2) (P < .05, P < .05). Conclusions. The congested liver segments showed high AF and high PI on CT perfusion imaging. This method enables the feasible quantification of the hemodynamics and the description of focal hemodynamic change in the graft after LDLT.