Does apparent diffusion coefficient predict the degree of liver regeneration of donor and recipient after living donor liver transplantation?

Objective To elucidate the relationship between the ADCs of the liver graft and the remnant liver and the degree of liver regeneration in LDLT. Materials and methods 15 recipients and 15 corresponding donors underwent magnetic resonance imaging and computed tomography 1–2 weeks after living donor liver transplantation (LDLT). For diffusion-weighted imaging (DWI), a single-shot echo-planar sequence with b-factors of 0, 500, and 1000 s/mm² was scanned. ADCs of the liver parenchyma were calculated at b factors of 0 and 500 and 1000 (ADC 0–500–1000) or 0 and 500 (ADC 0–500) or 500 and 1000 (ADC 500–1000). The liver volume ratio at LDLT, the mean ADCs and the regeneration rate were compared between the graft and the remnant liver using paired-t tests. Results The mean liver volume ratio of the recipients (41.3 ± 9.8%) tended to be smaller than that of the donors (51.8 ± 13.8%). The mean ADC 0–500 of the remnant liver (1.72 ± 0.33) was significantly higher than that of the graft (1.43 ± 0.32). The regeneration rate of the graft (2.07 ± 0.41) was significantly higher than that of the remnant liver (1.53 ± 0.49). Conclusion ADC 0–500 can describe differences in blood perfusion between liver grafts and the remnant liver according to the degree of liver regeneration.