Significance of CT attenuation value in liver grafts following right lobe living-donor liver transplantation

In adult living-donor liver transplantation (LDLT), the assessment of the allograft functional reserve is important for adequate graft regeneration. From March 2002 to December 2003, 30 adult recipients underwent right lobe LDLT. Mean CT attenuation values (CT-AVs) in the graft were measured on unenhanced CT for 6 months after LDLT. The histological features of the graft parenchyma were evaluated with post-operative liver biopsy specimens. Mean CT-AVs after LDLT were decreased significantly from the pre-operative values, recovered to over 60 HU within 6 months. There was a positive linear correlation between the CT-AVs and the receptor index (LHL15) in technetium-99m-diethylenetriaminepenta-acetic acid-galactosyl-human serum albumin (Tc-99m-GSA) liver scintigraphy (r = 0.803, p = 0.005). The recipients were divided into two groups according to the CT-AV at one post-operative week (group H; >= 55HU, group L; < 55HU). The low CT-AVs, under 55 HU, in group L were prolonged for 3 months compared with those in group H (p < 0.05). The 1-year cumulative survival rate was 94.7% and 45.5% in groups H and L, respectively (p = 0.014). Histological findings revealed that the parenchymal damage was severe in the grafts with low CT-AVs. The CT-AVs in the grafts may be a useful parameter for assessing the allograft functional reserve.