Search

Objective: To investigate the value of Doppler ultrasound (US) in recipients of living donor liver transplantation (LDLT) using modified right-lobe grafts (mRLGs) with obstruction of the middle hepatic vein tributaries (MHVTs)-interposition vessel graft (IVG)., Methods: This study included 240 consecutive LDLT recipients in whom 564 MHVTs (>5 mm) were reconstructed using IVG. Regular follow-up Doppler US was performed to assess the patency of the MHVTs-IVG and, if there was an obstruction, to evaluate for the establishment of collateral drainage. MHVTs with obstruction were subdivided into those with and without intrahepatic veno-venous collaterals on Doppler US and were correlated with CT scans., Results: MHVTs-IVG obstruction was identified in 137 patients with 227 MHVTs on follow-up Doppler US (6.2  ±  4.7 months). 90 patients with 149 MHVTs in whom the time interval between Doppler US and contrast-enhanced dynamic CT scans was <1 week were classified into either collateral (68 patients with 121 MHVTs) or non-collateral (22 patients with 28 MHVTs) groups. The presence of intrahepatic veno-venous collaterals on Doppler US were significantly related to no remarkable hepatic venous congestion on CT by both per-patient and per-vein analyses (66 of 68 patients (97.1%) and 118 of 121 MHVTs (97.5%), p < 0.001 and p < 0.001, respectively)., Conclusion: On Doppler US follow-up of LDLT recipients using mRLGs, identification of intrahepatic veno-venous collaterals associated with obstruction of MHVTs-IVG suggests no remarkable hepatic venous congestion. Advances in knowledge: When an obstruction of a MHVTs-IVG is encountered on Doppler US follow-up of LDLT recipients using mRLGs, no further evaluation with CT is warranted if intrahepatic veno-venous collaterals are observed on Doppler US, as this finding suggests no remarkable hepatic congestion.

The efficiency of hepatocyte transplantation into the liver varies with the method of administration. This study investigated whether retrograde infusion via the hepatic vein provides a sufficient number of donor cells for the liver. Donor hepatocytes were isolated from dipeptidyl peptidase IV (DPPIV(+)) rats and transplanted into DPPIV(-) rat livers either by antegrade portal vein infusion or retrograde hepatic vein infusion. Hepatocyte engraftment ratios and localization were evaluated by histological DPPIV enzymatic staining at 1 week and 8 weeks after the transplantation. No significant differences in engraftment efficiency were observed at either 1 week or 8 weeks after transplantation by either route. However, the localization of the transplanted hepatocytes differed with the administration route. Portal vein infusion resulted in predominantly periportal engraftment, whereas hepatic vein infusion led to pericentral zone engraftment. Immunohistochemical analysis showed that the transplanted hepatocytes engrafted in the pericentral zone after retrograde infusion displayed intense CYP2E1 staining similar to the surrounding native hepatocytes. CYP2E1 staining was further enhanced by administration of isosafrole, an inducing agent for various cytochrome P450 enzymes, including CYP2E1. This study demonstrates a novel approach of transplanting hepatocytes into the liver through retrograde hepatic vein infusion as the means to target cell implantation to the pericentral zone.

Background: The aim of this study was to delineate an algorithm for donor and recipient criteria and middle hepatic vein (MHV) management in right-graft live-donor liver transplantation (LDLT) on the basis of computerized 3-dimensional computed tomographic image analysis., Methods: Data on 94 consecutive right-graft LDLTs were prospectively collected. Graft and remnant data for the first 23 cases were retrospectively evaluated by means of 3-dimensional computed tomographic reconstructions, and on the basis of that preliminary series, a graft selection algorithm using 3 parameters-hepatic vein dominance classification, graft and remnant graft volume/body weight ratios, and congestion volumes-was created. It was subsequently applied to the next 71 right-graft LDLTs., Results: Fifty-nine right grafts contained the MHV. Four of the 12 grafts with no MHVs required MHV reconstructions. In 18 cases, small liver grafts were used. The postoperative function of liver grafts and remnants with versus without MHVs was not statistically different., Conclusions: The proposed algorithm favored the inclusion of the MHV with the right grafts. It also allowed for the procurement of grafts that were potentially small for size without compromising donor or recipient safety., (Copyright 2010. Published by Elsevier Inc.)

The clinical importance of congestion of the remnant right lobe has not yet been fully elucidated in donors who donate their left lobe with the middle hepatic vein. The impact of congestion on clinical course and liver regeneration in 52 donor remnant livers were evaluated. The donors were divided into three groups according to the degree of the congestion: the mild [congestion ratio (CR) < 10%], moderate (CR ranged from 10% to 25%) and severe congestion groups (CR > 25%). The regeneration ratio of the graft at postoperative day 7 (7 POD) was 22.0 +/- 14.3% and inversely correlated with the CR in the remnant right lobe (P = 0.003). Aspartate aminotransferase and alanine aminotransferase at 7 POD were significantly higher in the severe CR group in comparison to the mild CR group (P = 0.003 and 0.019, respectively), but those of the three groups were comparable at 30 POD. The hospital stays were significantly longer in the severe CR group (P = 0.010). In conclusion, the congestion of the donors' remnant right liver can lead the transient liver dysfunction and poor regeneration. Therefore, the conversion of the graft from the left to right lobe might be appropriate according to the degree of the congestion.

Objective: To investigate the feasibility and the clinical efficacy of right lobe including middle hepatic vein in adult-to-adult living donor liver transplantation., Method: We retrospectively analyzed the clinical data of 30 adult-to-adult living donor liver transplantation using right lobe including middle hepatic vein performed in our hospital from Feb. 2007 to Nov. 2007., Results: The right lobes weighed 540-1058 g (median 708 g). The remnant liver volumes were over 30% of the total liver volume in all donors. No perioperative death was noted for among donors and recipients. Complications were recorded and cured in 4 donors (13.3%) and 7 recipients (23.3%). All the donors and the recipients were followed up for 2-8 months (median 5 months), during which no donor died and 1 recipient died from aspergillus infection 4 months after operation., Conclusion: Adult-to-adult living donor liver transplantation using right lobe graft including middle hepatic vein is a safe and effective technique.

Background: In living donor liver transplantation, variations in donor vascular anatomy, recipient portal vein thrombosis, short donor vessel length, and reconstitution of the anterior sector outflow in right lobe grafts often make complex and innovative vascular reconstructions necessary, which require the use of extension vascular conduits. Commonly used grafts are cryopreserved vessels from deceased donors, or obtained from the recipient or the live liver donor. Faced with paucity of deceased donor vessels, and to avoid the use of live donor veins in patients with malignancy or unusable intrahepatic veins, we have started using cryopreserved veins harvested from explanted livers of other recipients of the same blood group who had no transmissible infection or intrahepatic malignancy., Methods: All veins were carefully harvested by meticulously ligating tributaries tested for leaks, hydrostatically distended with heparin before cryopreservation in liquid nitrogen and thawed gradually before use., Results: Out of 6 patients, cryopreserved veins were used: to reconstruct the anterior sector outflow of the extended right lobe graft in 4 patients; to reconstruct an aberrant 2 vein of a left lateral segment graft in 1; and to extend a short right portal vein in the other patient. Intraoperative and serial Doppler studies revealed patent anastomoses with good flow velocity with a mean follow-up of 7 months (range, 4-12 months)., Conclusions: Cryopreserved veins from explanted diseased livers are an important and previously untapped source of extension grafts that have good medium-term patency rates.

Objective: We sought to assess the impact of localized venous congestion related to venous deprivation on liver function recovery and regeneration after hepatectomy, using the living donation model. Harvesting the middle hepatic vein (MHV) optimizes the venous drainage of right grafts but could lead to donor segment IV congestion., Methods: In a series of 44 donors, 25 underwent right liver harvesting without the MHV and 19 with the MHV. The venous drainage anatomy of segment IV was defined as type I if exclusive through the MHV and type II if shared through the left hepatic vein. We prospectively studied the occurrence, magnitude (global or partial), and regeneration impacts of segment IV congestion on computed tomography (CT) performed 1 week and 1 month after surgery., Results: Early postoperative CT showed that segment IV congestion was never observed in the group without MHV harvesting, and it was present in 16 (84%) of 19 donors with MHV harvesting. Segment IV congestion was global in 9 donors, including 7 with type I anatomy. Postoperative data comparing data of the 9 donors with global congestion (GC) with other donors showed that the prothrombin time was significantly (P < .05) lower on day 1 and 5 (53% vs 63% and 76% vs 86%, respectively), and segment IV regeneration rate was lower (3.6% vs 11%) in the former group. However, a higher regeneration rate of segments II and III in the GC group (11.8% vs 3.6%) resulted in a similar regeneration rate of the remnant liver 1 month after hepatectomy (59.4 +/- 12% vs 57.8 +/- 12.4%)., Conclusions: Postoperative localized venous congestion is highly related to venous anatomy and affects both early postoperative liver function and regeneration rate. Based on this living donor model, we suggest that venous anatomy evaluation of the future remnant liver parenchyma be performed systematically before extended resection of living small or diseased remnants.

Imaging and management of postliver transplantation complications require an understanding of the surgical anatomy of liver transplantation. There are several methods of liver transplantation. Furthermore, liver transplantation is a complex surgery with numerous variables in its 4 anastomoses: (1) arterial anastomosis, (2) venous inflow (portal venous) anastomosis, (3) venous outflow (hepatic vein, inferior vena cava, or both) anastomosis, and (4) biliary/biliary-enteric anastomosis. The aim of this chapter is to introduce the principles of liver transplant surgical anatomy based on anastomotic anatomy. With radiologists as the target readers, the chapter focuses on the inflow and outflow connections and does not detail intricate surgical techniques or intraoperative maneuvers, operative stages, or vascular shunting.

A right lateral sector graft (RLSG) was devised to overcome graft-size disparity in living donor liver transplantation (LDLT). When the RLSG has a middle hepatic vein (MHV) tributary, which drains a significant part of segment VI, the MHV tributary (V6) should be reconstructed to avoid congestion of the RLSG. In the donor operation, congestive area of segment VI was identified by 5 minutes of simultaneous clamping of V6 and the hepatic artery to the right lateral sector. An RLSG was harvested, preserving the V6 orifice. After plastic surgery of outflow veins including V6 using venous grafts, the RLSG was implanted into the recipient. In 19 patients who received RLSG in our institution, 2 RLSGs required V6 reconstruction. The postoperative courses of these two recipients and donors were uneventful. In conclusion, the present technique might be useful to avoid complications due to congestion and poor function of the relevant graft area and might help to expand the indications for RLSG.

Objective: To evaluate the safety of donors who have donated the middle hepatic vein in right lobe live donor liver transplantation (LDLT) and to determine whether such inclusion is necessary for optimum graft function., Summary Background Data: The necessity to include the middle hepatic vein in a right lobe graft in adult-to-adult LDLT is controversial. Inclusion of the middle hepatic vein in the graft provides uniform hepatic venous drainage but may lead to congestion of segment IV in the donor., Methods: From 1996 to 2002, 93 right-lobe LDLTs were performed. All right-lobe grafts except 1 contained the middle hepatic vein. In the donor operation, attention was paid to preserve the segment IV hepatic artery and to avoid prolonged rotation of the right lobe. The middle hepatic vein was transected proximal to a major segment IVb hepatic vein whereas possible to preserve the venous drainage in the liver remnant., Results: There was no donor death. Two donors had intraoperative complications (accidental left hepatic vein occlusion and portal vein thrombosis) and were well after immediate rectification. Twenty-four donors (26%) had postoperative complications, mostly minor wound infection. The postoperative international normalized ratio on day 1 was better in the donors with preservation of segment IVb hepatic vein than those without the preservation, but, in all donors, the liver function was largely normal by postoperative day 7. The first recipient had severe graft congestion as the middle hepatic vein was not reconstructed before reperfusion. In 7 other recipients, the middle hepatic vein was found occluded intraoperatively owing to technical errors. The postoperative hepatic and renal function of the recipients with an occluded or absent middle hepatic vein was worse than those with a patent middle hepatic vein. The hospital mortality rate was also higher in those with an occluded middle hepatic vein (3/9 vs. 5/84, P = 0.028)., Conclusions: Inclusion of the middle hepatic vein in right-lobe LDLT is safe and is essential for optimum graft function and patient survival.