Factors influencing liver regeneration following living-donor liver transplantation of the right hepatic lobe.
BACKGROUND
As a result of the shortage of cadaveric livers for adults, many institutes perform living-donor liver transplantation (LDLT) using right-lobe grafts. It is important to learn whether regeneration of the graft is compromised by division of middle hepatic vein (MHV) tributaries. Accordingly, we studied the effect on graft regeneration of transection of the MHV tributaries and other factors, including graft versus body weight ratio (GRBW).


METHODS
Of 100 adult recipients having undergone right-lobe LDLT, 30 6-month survivors were studied. Liver regeneration was assessed by volumetry based on the computed tomography (CT). A regeneration index was defined as the ratio of the graft volume 6 months after LDLT to the preoperative value. The dominance of the MHV tributaries over the right hepatic vein in venous drainage of the anterior segment was evaluated by preoperative CT using a 5-point scale.


RESULTS
The regeneration index of the posterior segment was significantly greater than that of the anterior segment (Wilcoxon signed rank test, P=0.01). The relatively poor regeneration of the anterior segment compared with the whole graft was associated with preoperatively dominant MHV tributaries (Spearman rank correlation: R=-0.44, P=0.01). The only significant determinant of the whole-graft regeneration, however, was GRBW (stepwise regression: Y=-0.80X+0.2, R(2)=0.70, P<0.0001).


CONCLUSIONS
Despite deprivation of MHV tributaries, a graft will regenerate to meet the metabolic demand, and a smaller graft for the recipient is capable of regenerating to a greater extent.
Maetani
Yoji
Y
Department of Radiology, Kyoto University Graduate School of Medicine, Kyoto, Japan. mbo@kuhp.kyoto-u.ac.jp.
Itoh
Kyo
K
Egawa
Hiroto
H
Shibata
Toshiya
T
Ametani
Fumie
F
Kubo
Takeshi
T
Kiuchi
Tetsuya
T
Tanaka
Koichi
K
Konishi
Junji
J
D000293:Adolescent; D000328:Adult; D005260:Female; D006503:Hepatic Veins / Q000601:surgery; D006801:Humans; D008099:Liver / Q000000981:diagnostic imaging; D008115:Liver Regeneration / Q000502:physiology*; D016031:Liver Transplantation; D019520:Living Donors; D008297:Male; D008875:Middle Aged; D014057:Tomography, X-Ray Computed