Outcome of split liver transplantation vs living donor liver transplantation:A systematic review and meta-analysis

BACKGROUND The outcomes of liver transplantation(LT)from different grafts have been studied individually and in combination,but the reports were conflicting with some researchers finding no difference in both short-term and long-term outcomes between the deceased donor split LT(DD-SLT)and living donor LT(LDLT).AIM To compare the outcomes of DD-SLT and LDLT we performed this systematic review and meta-analysis.METHODS This systematic review was performed in compliance with the Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines.The following databases were searched for articles comparing outcomes of DD-SLT and LDLT:PubMed;Google Scholar;Embase;Cochrane Central Register of Controlled Trials;the Cochrane Database of Systematic Reviews;and Reference Citation Analysis(https://www.referencecitationanalysis.com/).The search terms used were:“liver transplantation;”“liver transplant;”“split liver transplant;”“living donor liver transplant;”“partial liver transplant;”“partial liver graft;”“ex vivo splitting;”and“in vivo splitting.”RESULTS Ten studies were included for the data synthesis and meta-analysis.There were a total of 4836 patients.The overall survival rate at 1 year,3 years and 5 years was superior in patients that received LDLT compared to DD-SLT.At 1 year,the hazard ratios was 1.44(95%confidence interval:1.16-1.78;P=0.001).The graft survival rate at 3 years and 5 years was superior in the LDLT group(3 year hazard ratio:1.28;95%confidence interval:1.01-1.63;P=0.04).CONCLUSION This meta-analysis showed that LDLT has better graft survival and overall survival when compared to DD-SLT.

Small for size syndrome difficult dilemma: Lessons from 10 years single centre experience in living donor liver transplantation

AIM To analyze the incidence, risk factors, prevention, treatment and outcome of small for size syndrome(SFSS) after living donor liver transplantation(LDLT). METHODS Through-out more than 10 years: During the period from April 2003 to the end of 2013, 174 adult-to-adults LDLT(A-ALDLT) had been performed at National Liver Institute, Menoufiya University, Shibin Elkoom, Egypt. We collected the data of those patients to do this cohort study that is a single-institution retrospective analysis of a prospectively collected database analyzing the incidence, risk factors, prevention, treatment and outcome of SFSS in a period started from the end of 2013 to the end of 2015. The median period of follow-up reached 40.50 m, range(0-144 m). RESULTS SFSS was diagnosed in 20(11.5%) of our recipients. While extra-small graft [small for size graft(SFSG)], portal hypertension, steatosis and left lobe graft were significant predictors of SFSS in univariate analysis(P = 0.00, 0.04, 0.03, and 0.00 respectively); graft size was the only independent predictor of SFSS on multivariate analysis(P = 0.03). On the other hand, there was lower incidence of SFSS in patients with SFSG who underwent splenectomy [4/10(40%) SFSS vs 3/7(42.9%) no SFSS] but without statistical significance, However, there was none significant lower incidence of the syndrome in patients with right lobe(RL) graft when drainage of the right anterior and/or posterior liver sectors by middle hepatic vein, V5, V8, and/or right inferior vein was done [4/10(28.6%) SFSS vs 52/152(34.2%) no SFSS]. The 6-mo, 1-, 3-, 5-, 7-and 10-year survival in patients with SFSS were 30%, 30%, 25%, 25%, 25% and 25% respectively, while, the 6-mo, 1-, 3-, 5-, 7-and 10-year survival in patients without SFSS were 70.1%, 65.6%, 61.7%, 61%, 59.7%, and 59.7% respectively, with statistical significant difference(P = 0.00). CONCLUSION SFSG is the independent and main factor for occurrence of SFSS after A-ALDLT leading to poor outcome. However, the management of this catastrophe depends upon its prevention(i.e., selecting graft with proper size, splenectomy to decrease portal venous inflow, and improving hepatic vein outflow by reconstructing large draining veins of the graft).

Clinical study on safety of adult-to-adult living donor liver transplantation in both donors and recipients

AIM： TO investigate the safety of adult-to-adult living donor liver transplantation （A-A LDLT） in both donors and recipients. METHODS： From January 2002 to July 2006, 50 cases of A-A LDLT were performed at West China Hospital, Sichuan University, consisting of 47 cases using right lobe graft without middle hepatic vein （HHV）, and 3 cases using dual grafts （one case using two left lobe, 2 using one right lobe and one left lobe）. The most common diagnoses were hepatitis B liver cirrosis, 30 （60%） cases; and hepatocellular carcinoma, 15 （30%） cases in adult recipients. Among them, 10 cases had the model of end-stage liver disease （HELD） with a score of more than 25. Donor screening consisted of reconstruction of the hepatic blood vessels and biliary system with 3-dimension computed tomography and volumetry of whole liver and right liver volume. Various improved surgical techniques were adopted in the procedures for both donors and recipients. RESULTS： Forty-nine right lobes and 3 left lobes （2 left lobe grafts for 1 recipient, 1 left lobe graft for 1 recipient who had received right lobe graft donated by relative living donor） were obtained from 52 living donors. The 49 right lobe grafts, without HHV, weighed 400 g-850 g （media 550 g）, and the ratio of graft volume to recipient standard liver volume （GV/SLV） ranged from 31.74% to 71.68% （mean 45.35%）. All donors＇ remnant liver volume was over 35% of the whole liver volume. There was no donor mortality. With a follow- up of 2-52 mo （media 9 too）, among 50 adult recipients, complications occurred in 13 （26%） cases and 4 （8%） died postoperatively within 3 mo. Their 1-year actual survival rate was 92%.CONCLUSION： When preoperative CT volumetry shows volume of remnant liver is more than 350, the ratio of right lobe graft to recipients standard liver volume exceeding 40%, A-A LDLT using right lobe graft without MHV should be a very safe procedure for both donors and recipients, otherwise dual grafts liver transplantation should be considered.

Analysis of infections in the first 3-month after living donor liver transplantation

AIM:To identify factors related to serious postoperative bacterial and fungal infections in the first 3 mo after living donor liver transplantation(LDLT).METHODS:In the present study,the data of 207 patients from 2004 to 2011 were reviewed.The pre-,intra-and post-operative factors were statistically analyzed.All transplantations were approved by the ethics committee of West China Hospital,Sichuan University.Patients with definitely preoperative infections and infections within 48 h after transplantation were excluded from current study.All potential risk factors were analyzed using univariate analyses.Factors significant at a P < 0.10 in the univariate analyses were involved in the multivariate analyses.The diagnostic accuracy of the identified risk factors was evaluated using receiver operating curve.RESULTS:The serious bacterial and fungal infection rates were 14.01% and 4.35% respectively.Enterococcus faecium was the predominant bacterial pathogen,whereas Candida albicans was the most common fungal pathogen.Lung was the most common infection site for both bacterial and fungal infections.Recipient age older than 45 years,preoperative hyponatremia,intensive care unit stay longer than 9 d,postoperative bile leak and severe hyperglycemia were independent risk factors for postoperative bacterial infection.Massive red blood cells transfusion and postoperative bacterial infection may be related to postoperative fungal infection.CONCLUSION:Predictive risk factors for bacterial and fungal infections were indentified in current study.Pre-,intra-and post-operative factors can cause postoperative bacterial and fungal infections after LDLT.

Management of the middle hepatic vein and its tributaries in right lobe living donor liver transplantation

BACKGROUND: Left liver graft from a small donor will not meet the metabolic demands of a larger adult recipient. To overcome the problem of graft size insufficiency, living donor liver transplantation (LDLT) using the right lobe has become a standard method for adult patients. As the drainage of the median sector (segments V, VIII and IV) is mainly by the middle hepatic vein (MHV), the issue of whether the MHV should or should not be taken with the graft or whether the MHV tributaries (V5, V8) should be reconstructed in the recipient remains to be settled. DATA SOURCES: An English-language literature search was conducted using MEDLINE (1985-2006) on right lobe living donor liver transplantation, middle hepatic vein, vein graft, hepatic venoplasty and other related subjects. RESULTS: Some institutions had proposed their policy for the management of the MHV and its tributaries. Dominancy of the hepatic vein, graft-to-recipient weight ratio, and remnant liver volume as well as the donor-to-recipient body weight ratio, the volume of the donor's right lobe to the recipient's standard liver volume and the size of MHV tributaries are the major elements for the criteria of inclusion of the MHV, while for the policy of MHV tributaries reconstruction, the proportion of congestive area and the diameter of the tributaries are the critical elements. Optimal vein grafts such as recipient's portal vein and hepatic venoplasty technique have been used to obviate hepatic congestion and venous drainage disturbance. CONCLUSIONS: Taking right liver grafts with the MHV trunk (extended right lobe grafts) or performing the MHV tributaries reconstruction in modified right lobe grafts, according to the criteria proposed by the institutions with rich experience, can solve the congestion problem of the right paramedian sector and help to improve the outcomes of the patients. The additional use of optimal vein grafts and hepatic venoplasty also can guarantee excellent venous drainage.

Challenge to ABO blood type barrier in living donor liver transplantation

ABO incompatible living donor liver transplantation has the potential to expand the donor pool for patients with end stage liver diseases on the expense of challenges to overcome immunological barriers across blood type.There is a profound impact of age on incidence and severity of antibody mediated rejection(AMR).Even children older than 1 year have chances of AMR;children aged 8 years or older have risks of hepatic necrosis similar to adult liver recipients.The mechanism of AMR is based on circulatory disturbances secondary to inflammation and injury of the vascular endothelium caused by an antibody-antigen-complement reaction.The strategy to overcome ABO blood type barrier is based on both pre-transplant desensitization and adequate treatment of this phenomenon.Nowadays,rituximab is the standard means of desensitization but unfortunately an insufficient aid to treat AMR.Because of low incidence(less than 5%in the rituximab era),in practice of AMR only some case reports about the treatment of clinical AMR are available in the literature.Initial experiences revealed that the proteasome inhibitor,bortezomib might be a promising treatment based on its capacity to deplete plasma cell agents.Although ABO blood type barrier has been counteracted in 95%of patients by applying“rituximab-desensitization”,many issues,such as prediction of high-risk patients of infection and AMR and secure treatment strategies for evoked AMR,remain to be resolved.

Graft-to-recipient weight ratio lower to 0.7% is safe without portal pressure modulation in right-lobe living donor liver transplantation with favorable conditions

BACKGROUND: The low graft-to-recipient weight ratio(GRWR) in adult-to-adult living donor liver transplantation(LDLT) is one of the major risk factors affecting graft survival. The goal of this study was to evaluate whether the lower limit of the GRWR can be safely reduced without portal pressure modulation in right-lobe LDLT. METHODS: From 2005 to 2011, 317 consecutive patients from a single institute underwent LDLT with right-lobe grafts without portal pressure modulation. Of these, 23 had a GRWR of less than 0.7%(group A), 27 had a GRWR of ≥0.7%, 【0.8%(group B), and 267 had a GRWR of more than and equal to 0.8%(group C). Medical records, including recipient, donor, operation factors, laboratory findings and complications were reviewed retrospectively. RESULTS: The baseline demographics showed low model for end-stage liver disease score(mean 16.3±8.9) and high percentage of hepatocellular carcinoma(231 patients, 72.9%). Three groups by GRWR demonstrated similar characteristics except recipient body mass index and donor gender. For smallforsize syndrome, there were 3(13.0%) in group A, 1(3.7%) in group B, and 2 patients(0.7%) in group C(P【0.001). Hepatic artery thrombosis was more frequently observed in group A than in groups B and C(8.7% vs 3.7% vs 1.9%, P=0.047). However, among the three groups, graft survival rates at 1 year(100% vs 96.3% vs 93.6%) and 3 years(91.7% vs 73.2% vs 88.1%) were not different(P=0.539). In laboratory measurements,there was no group difference in total bilirubin and albumin. However, prothrombin time was longer in group A within postoperative 1 week and platelet count was lower in groups A and B within postoperative 1 month. CONCLUSION: A GRWR lower to 0.7% is safe and does not need to modulate portal pressure in adult-to-adult LDLT using the right-lobe in favorable conditions including low model for end-stage liver disease score.

Hepatobiliary scintigraphy for detecting biliary strictures after living donor liver transplantation

AIM:To investigate the diagnostic accuracy of hepatobiliary scintigraphy(HBS) in detecting biliary strictures in living donor liver transplantation(LDLT) patients.METHODS:We retrospectively reviewed 104 adult LDLT recipients of the right hepatic lobe with duct-toduct anastomosis,who underwent HBS and cholangiography.The HBS results were categorized as normal,parenchymal dysfunction,biliary obstruction,or bile leakage without re-interpretation.The presence of biliary strictures was determined by percutaneous cholangiography or endoscopic retrograde cholangiopancreatography(ERCP).RESULTS:In 89 patients with biliary strictures,HBS showed biliary obstruction in 50 and no obstruction in 39,for a sensitivity of 56.2%.Of 15 patients with no biliary strictures,HBS showed no obstruction in 11,for a specificity of 73.3%.The positive predictive value(PPV) was 92.6%(50/54) and the negative predictive value(NPV) was 22%(11/50).We also analyzed the diagnostic accuracy of the change in bile duct size.The sensitivity,NPV,specificity,and PPV were 65.2%,27.9%,80% and 95%,respectively.CONCLUSION:The absence of biliary obstruction on HBS is not reliable.Thus,when post-LDLT biliary strictures are suspected,early ERCP may be considered.

Modified techniques for adult-to-adult living donor liver transplantation

BACKGROUND: Because of critical organ shortage, transplant professionals have utilized living donor liver transplantation (LDLT) in recent years. We summarized our experience in adult-to-adult LDLT with grafts of right liver lobe by a modified technique. METHODS: From January 2002 to August 2005, 24 adult patients underwent living donor liver transplantation with grafts of the right liver lobe at West China Hospital, Sichuan University, China. Twenty-two patients underwent modi-Bed procedures designed to improve the reconstruction of the right hepatic vein and the tributaries of the middle hepatic vein by interposing a great saphenous vein ( GSV) graft and the anastomosis of the hepatic arteries and bile ducts. RESULTS: No severe complications and death occurred in all donors. In the first 2 patients, (patients 1 and 2), operative procedure was not modified. One patient suffered from 'small-for-size syndrome' and the other died of sepsis with progressive deterioration of graft function. In the rest 22 patients (patients 3 to 24), however, the procedure of venous reconstruction was modified, and better results were obtained. Complications occurred in 7 recipients including acute rejection (2 patients), hepatic artery thrombosis (1), bile leakage (1), intestinal bleeding (1), left sub-phrenic abscess (1), and pulmonary infection (1). One patient with pulmonary infection died of multiple organ failure (MOF). The 22 patients underwent direct anastomosis of the right hepatic vein to the inferior vena cava (IVC), 9 direct anastomosis plus the reconstruction of the right inferior hepatic vein, and 10 direct anastomosis plus the reconstruction of the tributaries of the middle hepatic vein by in-terpos-ing a GSV graft to provide sufficient venous outflow. Trifurcation of the portal vein was met in 3 patients. Venoplasty or separate anastomosis was performed. The ratio of graft to recipient body weight ranged from 0.72% to 1.17%. Among these patients, 19 had the ratio <1.0% and 4 <0.8%, and the ratio of graft weight to recipient standard liver volume was between 31.86% and 62.48%. Among these patients, 10 had the ratio <50% and 2 <40%. No 'small-for-size syndrome' occurred in the 22 recipients who were subjected to modified procedures. CONCLUSIONS: With the modified surgical techniques for the reconstruction of the hepatic vein to obtain an adequate outflow and provide a sufficient functioning liver mass, living donor liver graft in adults using the right lobe can be safe to prevent the 'small-for-size syndrome'.

Outcome of patients undergoing right lobe living donor liver transplantation with small-for-size grafts

AIM: To investigate the outcome of living donor liver transplantation (LDLT) recipients transplanted with small-for-size grafts (SFSGs). METHODS: Between November 2001 and December 2010, 196 patients underwent LDLT with right lobe liver grafts at our center. Recipients were divided into 2 treatment groups: group A with an actuarial graft-to-recipient weight ratio (aGRWR) < 0.8% (n = 45) and group B with an aGRWR = 0.8% (n = 151). We evaluated serum liver function markers within 4 wk after transplantation. We also retrospectively evaluated the outcomes of these patients for potential effects related to the recipients, the donors and the transplantation procedures based upon a review of their medical records. RESULTS: Small-for-size syndrome (SFSS) developed in 7 of 45 patients (15.56%) in group A and 9 of 151 patients (5.96%) in group B (P = 0.080). The levels of alanine aminotransferase and aspartate aminotransferase in group A were higher than those in group B during early period after transplantation, albeit not sig-nificantly. The cumulative 1-, 3-and 5-year liver graft survival rates were 82.22%, 71.11% and 71.11% for group A and 81.46%, 76.82%, and 75.50% for group B patients, respectively (P = 0.623). However, univariate analysis of risk factors associated with graft survival in group A demonstrated that the occurrence of SFSS after LDLT was the only significant risk factor affecting graft survival (P < 0.001). Furthermore, multivariate analysis of our data did not identify any additional significant risk factors accounting for poor graft survival. CONCLUSION: Our study suggests that LDLT recipients with an aGRWR < 0.8% may have liver graft outcomes comparable to those who received larger size grafts. Further studies are required to ascertain the safety of using SFSGs. (c) 2014 Baishideng Publishing Group Co., Limited. All rights reserved.

Adult-to-adult right lobe living donor liver transplantation:Comparison of endoscopic retrograde cholangiography with standard T2-weighted magnetic resonance cholangiography for evaluation of donor biliary anatomy

AIM: To compare the value of endoscopic retrograde cholangiography (ERC) and standard T2-weighted magnetic resonance cholangiography (MRC) in the evaluation process as adult-to-adult right lobe living donor liver transplantation (LDLTx) demands a successful outcome, and exact knowledge of the biliary tree is implicated to avoid biliary complications, postoperatively.METHODS: After starting the LDLTx program, 18 liver transplant candidates were selected for LDLTx by a stepwise evaluation process. ERC and standard T2-weighted MRC were performed to evaluate the biliary system of the donor liver. The anatomical findings of ERC and MRC mapping were compared using the Ohkubo classification. RESULTS: ERC allowed mapping of the whole biliary system in 15/15 (100%) cases, including 14/15 (93.3%) with biliary variants while routine MRC was only accurate in 2/13 (15.4%) cases. MRC was limited in depicting the biliary system proximal of the hepatic bifurcation. Postoperative biliary complications occurred in 2 donors and 8 recipients. Biliary complications were associated with Ohkubo type C, E or G in 6/8 recipients, and 2/3 recipients with biliary leak received a graft with multiple (≥2) bile ducts. CONCLUSION: Pretransplant ERC is safe and superior over standard MRC for detection of biliary variations that occur with a high frequency. However, precise knowledge of biliary variants did not reduce the incidence of postoperative biliary complications.

Survival outcomes of right-lobe living donor liver transplantation for patients with high Model for End-stage Liver Disease scores

BACKGROUND: Controversy exists over whether living donor liver transplantation (LDLT) should be offered to patients with high Model for End-stage Liver Disease (MELD) scores. This study tried to determine whether a high MELD score would result in inferior outcomes of right-lobe LDLT. METHODS: Among 411 consecutive patients who received right-lobe LDLT at our center, 143 were included in this study. The patients were divided into two groups according to their MELD scores: a high-score group (MELD score ≥25; n=75) and a low-score group (MELD score 【25; n=68). Their demographic data and perioperative conditions were compared. Univariable and multivariable analyses were performed to identify risk factors affecting patient survival. RESULTS: In the high-score group, more patients required preoperative intensive care unit admission (49.3% vs 2.9%; P【0.001), mechanical ventilation (21.3% vs 0%; P【0.001), or hemodialysis (13.3% vs 0%; P=0.005); the waiting time before LDLT was shorter (4 vs 66 days; P【0.001); more blood was transfused during operation (7 vs 2 units; P【0.001); patients stayed longer in the intensive care unit (6 vs 3 days; P【0.001) and hospital (21 vs 15 days; P=0.015) after transplantation;more patients developed early postoperative complications (69.3% vs 50.0%; P=0.018); and values of postoperative peak blood parameters were higher. However, the two groups had comparable hospital mortality. Graft survival and patient overall survival at one year (94.7% vs 95.6%; 95.9% vs 96.9%), three years (91.9% vs 92.6%; 93.2% vs 95.3%), and five years (90.2% vs 90.2%; 93.2% vs 95.3%) were also similar between the groups. CONCLUSIONS: Although the high-score group had signifi-cantly more early postoperative complications, the two groups had comparable hospital mortality and similar satisfactory rates of graft survival and patient overall survival. Therefore, a high MELD score should not be a contraindication to right-lobe LDLT if donor risk and recipient benefit are taken into full account.

Effect of donor age on graft function and longterm survival of recipients undergoing living donor liver transplantation

BACKGROUND： Donor shortage is the biggest obstacle in organ transplantation. Living donor liver transplantation（LDLT） has been considered as a valuable approach to shortening waiting time. The objectives of this study were to investigate the feasibility of utilizing donors older than 50 years in LDLT and to evaluate the graft function and recipient survival.METHODS： All LDLT cases（n=159） were divided into the older（donor age ≥50 years, n=10） and younger（donor age 〈50 years,n=149） donor groups. Donor graft and recipient condition pre-,intra- and post-operation were compared between the two groups.In particular, graft functions and recipient survivals were analyzed.RESULTS： The median donor age was 58.5（52.5-60.0） years in the older donor group and 25.0（23.0-32.0） in the younger donor group. There was no significant difference in cold ischemic time, anhepatic phase and operation time between the older and younger donor groups（P〉0.05）. However, the volume of red blood cell transfused in operation was greater in the older donor group than in the younger donor group（1900 vs 1200 m L, P=0.023）. The 1-, 3- and 5-year graft survival rates were 90%, 80% and 80% for the older donor group, and 92%, 87% and 87% for the younger donor group, respectively（P=0.459）.The 1-, 3- and 5-year survival rates were 100%, 90% and 90% for recipients with older grafts, and 93%, 87% and 87% for those with younger grafts, respectively（P=0.811）.CONCLUSION： It is safe for a LDLT recipient to receive liver from donors older than 50 years, and there is no significant adverse effect on graft function and long-term patients’ survival.

Late-onset acute rejection after living donor liver transplantation

AIM： TO investigate the incidence and risk factors of late-onset acute rejection （LAR） and to clarify the effectiveness of our immunosuppressive regime consisting of life-long administration of tacrolimus and steroids. METHODS： Adult living donor liver transplantation recipients （n = 204） who survived more than 6 mo after living donor liver transplantation were enrolled. Immunosuppression was achieved using tacrolimus and methylprednisolone. When adverse effects of tacrolimus were detected, the patient was switched to cyclosporine. Six months after transplantation, tacrolimus or cyclosporine was carefully maintained at a therapeutic level. The methylprednisolone dosage was maintained at 0.05 mg/kg per day by oral administration. Acute rejections that occurred more than 6 mo after the operation were defined as late-onset. The median follow-up period was 34 too. RESULTS： LAR was observed in 15 cases （7%） and no chronic rejection was observed. The incidence of hyperlipidemia, chronic renal failure, new-onset post-transplantation diabetes, and deep fungal infection were 13%, 2%, 24%, and 17%, respectively. Conversion from tacrolimus to cyclosporine was required in 38 patients （19%）. Multivariate analysis revealed that a cyclosporine-based regimen was significantly associated with LAR.events happen at a low incidence, supporting the safety and efficacy of the present immunosuppression regimen for living donor liver transplantation.

Hepatic vein in living donor liver transplantation

Right lobe living donor liver transplantation(LDLT)is a major development in adult LDLT that has significantly increased the donor pool by providing larger graft size and by decreasing risk of small-for-size graft syndrome.However,right lobe anatomy is complex,not only from the inflow but also from the outflow perspective.Outflow reconstruction is one of the key requirements of a successful LDLT and venous drainage of the liver graft is just as important as hepatic inflow for the integrity of graft function.Outflow complications may cause acute graft failure which is not always easy to diagnose.The right lobe graft consists of two sections and three hepatic venous routes for drainage that require reconstruction.In order to obtain a congestion free graft,several types of vascular conduits and postoperative interventions are needed to assure an adequate venous allograft drainage.This review described the anatomy,functional basis and the evolution of outflow reconstruction in right lobe LDLT.

Management of the Middle Hepatic Vein in Right Lobe Living Donor Liver Transplantation: A Meta-analysis

Summary： Living donor liver transplantation （LDLT） is a curative treatment for end stage liver disease. It is advantageous due to the shortage of deceased donors. However, in LDLT, whether the middle he- patic vein （MHV） should be preserved in donors remains controversial. We conducted searches in Pub- reed, Embase, Cochrane Library, Web of Science, Ovid, and Google Scholar using the key words ＂living donor liver transplantation＂ and ＂middle hepatic vein＂. Due to ethical issues, there were no randomized control trails focusing on MHV in LDLT. The majority of reports were retrospective studies. We exam- ined the reference lists to identify related investigations. Google Scholar was then used to obtain full texts. Nine observational studies were analyzed. There were no significant differences in liver function （WMD, -5.51; P=0.12） and complications （RR, 0.98; P=0.89） in donors with or without MHV. How- ever, the liver function in recipients was greatly improved after LDLT with MHV （WMD, -78.32; P=0.01）. No definite conclusion was obtained in terms of the liver regeneration indices between LDLT with or without MHV. It was conclude that grafts with MHV in LDLT favor recipient outcomes and do not harm the living donor if a careful preoperative evaluation is oerformed.

Clostridium difficile-associated diarrhea after living donor liver transplantation

AIM： To assess the incidence and analyze the risk factors for Clostridium difficile-associated diarrhea （CDAD）after living donor liver transplantation （LDLT） in adult.METHODS： The micobiological data and medical records of 242 adult recipients that underwent LDLT at the Tokyo University Hospital were analyzed retrospectively. The independent risk factors for postoperative CDAD were identified.RESULTS： Postoperative CDAD occurred in 11 （5%）patients. Median onset of CDAD was postoperative d 19（range, 5-54）. In the multivariate analyses, male gender （odds ratio, 4.56） and serum creatinine （≥ 1.5 mg/dL,odds ratio, 16.0） independently predicted postoperative CDAD.CONCLUSION： CDAD should be considered in the differential diagnosis of patients with postoperative diarrhea after LDLT.

Living donor liver transplantation for high model for endstage liver disease score:What have we learned?

AIM: To assess the impact of model for end-stage liver disease(MELD) score on patient survival and morbidity post living donor liver transplantation(LDLT). METHODS: A retrospective study was performed on 80 adult patients who had LDLT from 2011-2013. Nine patients were excluded and 71 patients were divided into two groups; Group 1 included 38 patients with a MELD score < 20, and Group 2 included 33 patients with a MELD score > 20. Comparison between both groups was done regarding operative time, intra-operative blood requirement, intensive care unit(ICU) and hospital stay, infection, and patient survival.RESULTS: Eleven patients died(15.5%); 3/38(7.9%)patients in Group 1 and 8/33(24.2%) in Group 2 with significant difference(P = 0.02). Mean operative time, duration of hospital stay, and ICU stay were similar in both groups. Mean volume of blood transfusion and cell saver re-transfusion were 8 ± 4 units and 1668 ± 202 m L, respectively, in Group 1 in comparison to 10 ± 6 units and 1910 ± 679 m L, respectively, in Group 2 with no significant difference(P = 0.09 and 0.167, respectively). The rates of infection and systemic complications(renal, respiratory, cardiovascular and neurological complications) were similar in both groups. CONCLUSION: A MELD score > 20 may predict mortality after LDLT.

Sonographic evaluation of vessel grafts in living donor liver transplantation recipients of the right lobe

AIM： To evaluate the vessel grafts （VG） used to reconstruct the middle hepatic vein （MHV） tributaries with ultrasonography. METHODS： Twenty-four patients undergone living donor liver transplantation were enrolled in our study. MHV tributaries larger than 5 mm in diameter were reconstructed with interposition VG. Blood flow of the graft and interposition VG was checked by Doppler ultrasonography daily in the first 2 postoperative weeks and monthly followed up after discharge. The sensitivity of VG detected by ultrasonography was assessed using surgical records as references. Student＇s t test was used to compare the velocity of VG and occluded VG in chronic patents （〉 3 mo）. RESULTS： Thirty-one VG were used to reconstruct the MHV tributaries. Ultrasonography identified 96.7% （30/31） of large MHV tributaries and 90.3% （28/31） of VG. The diameter of VG was 5.6 ± 0.8 mm and the velocity of VG was 19.7 ± 8.1 cm/s. Two VG （2/31, 6.5%） were occluded on the first postoperative day in one patient who suffered from persistent ascites and had a prolonged recovery of liver function. Twenty-six VG （26/31, 83.9%） were patent 2 wk after operation. Six （6/31, 19.4%） VG were patent over 3 mo after operation. Intrahepatic venous collaterals were detected in 29.2% （7/24） patients. The velocity of VG and occluded VG was 30.1 ± 5.6 cm/s, 16.5 ± 5.8 cm/s, respectively, in chronic patents. The difference between two groups was statistically significant （P 〈 0.001）. CONCLUSION： Our results indicate that most VG are patent in the first postoperative week while only a small portion with a higher velocity remains patent after 3 mo. Intrahepatic venous collaterals can be observed in some patients after occlusion of VG.

Uses of a dedicated 3D reconstruction software with augmented and mixed reality in planning and performing advanced liver surgery and living donor liver transplantation(with videos)

The development of digital intelligent diagnostic and treatment technology has opened countless new opportunities for liver surgery from the era of digital anatomy to a new era of digital diagnostics,virtual surgery simulation and using the created scenarios in real-time surgery using mixed reality.In this article,we described our experience on developing a dedicated 3 dimensional visualization and reconstruction software for surgeons to be used in advanced liver surgery and living donor liver transplantation.Furthermore,we shared the recent developments in the field by explaining the outreach of the software from virtual reality to augmented reality and mixed reality.