Nam-Joon Yi

Laparoscopy-Assisted Donor Right Hepatectomy Using a Hand Port System Preserving the Middle Hepatic Vein Branches

BackgroundThis report reviews our experience with a modified right hepatectomy (MRH) using laparoscopic or laparoscopy-assisted techniques preserving the middle hepatic vein (MHV) branches in living donor liver transplantation.MethodsNine female donors (17–36xa0years) underwent a laparoscopic MRH under pneumoperitoneum (L-MRH; nxa0=xa02) or a laparoscopy-assisted MRH (LA-MRH; nxa0=xa07) with a hand port device. The donors for this minimally invasive surgery were volunteers with the willingness to undergo laparoscopic surgery and recipients who were not in urgent need of transplantation. Mobilization of the right liver was performed under pneumoperitoneum in all cases. Hilar dissection and parenchymal transection were performed under pneumoperitonuem (nxa0=xa02) or with a mini-laparotomy incision (nxa0=xa07) using an ultrasonic aspirator without the Pringle maneuver. The major MHV branches (>5xa0mm) were preserved using Hem-o-lock clips. The graft was extracted through the site of the hand port device or the mini-laparotomy. On the back table, the MHV branches were reconstructed with an artificial vascular graft.ResultsThere were no open conversions, and the graft was transplanted without any problem in every case. The operative time for the donors was 765xa0min and 898xa0min in the L-MRH patients, and it ranged from 310 to 575xa0min for the laparoscopy-assisted surgery. None of the donors required transfusion or reoperation; they were discharged on postoperative day 8–14 with normal liver function. A major complication occurred in one donor; fluid collection along the liver resection margin with fever was treated and resolved after percutaneous drainage.ConclusionsA right hepatectomy preserving the MHV or its branches by minimally invasive techniques including total laparoscopic surgery was technically feasible. However, further refinements of the procedure are required prior to wide clinical application.

Platelet Transfusion can be Related to Liver Regeneration After Living Donor Liver Transplantation

BackgroundAlthough liver regeneration is a fundamental aspect of living donor liver transplantation (LDLT), the factors that affect liver regeneration during the early post-transplantation period have not been thoroughly investigated. Recently it was suggested that platelets contribute to liver regeneration. The aim of the present study was to identify the major factors that affect liver graft regeneration during the early post-transplantation period.Materials and methodsEighty-seven right liver grafted, adult-to-adult LDLT patients were retrospectively analyzed. Liver regeneration was assessed by volumetry from computed tomographic (CT) scans obtained between the 9th and 11th postoperative days. The authors investigated relationships between clinical variables and liver graft regeneration rates, and they conducted multiple regression analysis on factors found to be significant by univariate analysis.ResultsMean graft weight at operation was 722.9xa0±xa0109.7xa0g, and mean graft volume assessed by follow-up CT was 1,042.2xa0±xa0155.6xa0ml, reflecting a mean liver graft regeneration of 45.9xa0±xa022.3%. The graft regeneration was found to correlate inversely with graft-to-recipient weight ratio (GRWR, rxa0=xa0−0.406, pxa0<xa00.001) and directly with portal flow velocity (cm/s; rxa0=xa00.307; pxa0=xa00.004) and splenic index (cm3; rxa0=xa00.282; pxa0=xa00.009). Moreover, the total amount (units) of platelets transfused was found to be significantly associated with graft regeneration (rxa0=xa00.293; pxa0=xa0−.006). Stepwise regression analysis showed that GRWR (βxa0=xa0−33.124; pxa0=xa00.001), total amount of platelets transfused (βxa0=xa00.771; pxa0=xa00.012), and splenic index (βxa0=xa0−0.010; pxa0=xa00.049) were independently associated with graft regeneration.ConclusionsThe results of the present study suggest that platelets play a significant role in human liver regeneration after LDLT.

Percutaneous Transsplenic Access to the Portal Vein for Management of Vascular Complication in Patients with Chronic Liver Disease

PurposeTo evaluate the safety and feasibility of percutaneous transsplenic access to the portal vein for management of vascular complication in patients with chronic liver diseases.MethodsBetween Sept 2009 and April 2011, percutaneous transsplenic access to the portal vein was attempted in nine patients with chronic liver disease. Splenic vein puncture was performed under ultrasonographic guidance with a Chiba needle, followed by introduction of a 4 to 9F sheath. Four patients with hematemesis or hematochezia underwent variceal embolization. Another two patients underwent portosystemic shunt embolization in order to improve portal venous blood flow. Portal vein recanalization was attempted in three patients with a transplanted liver. The percutaneous transsplenic access site was closed using coils and glue.ResultsPercutaneous transsplenic splenic vein catheterization was performed successfully in all patients. Gastric or jejunal varix embolization with glue and lipiodol mixture was performed successfully in four patients. In two patients with a massive portosystemic shunt, embolization of the shunting vessel with a vascular plug, microcoils, glue, and lipiodol mixture was achieved successfully. Portal vein recanalization was attempted in three patients with a transplanted liver; however, only one patient was treated successfully. Complete closure of the percutaneous transsplenic tract was achieved using coils and glue without bleeding complication in all patients.ConclusionPercutaneous transsplenic access to the portal vein can be an alternative route for portography and further endovascular management in patients for whom conventional approaches are difficult or impossible.

Current role of surgery in treatment of early stage hepatocellular carcinoma: resection versus liver transplantation.

Hepatocellular carcinoma (HCC) is the most common malignancy of the liver and is most commonly associated with hepatitis B infection in Korea. Although liver resection is regarded as a potentially curative treatment option, it is only feasible in less than 20% of patients. The reason for this is that HCC arises in cirrhotic livers and is often multicentric. Liver transplantation (LT) which could be used in the treatment both of the tumor and background liver seems to be a rational approach for early stage patients with decompensated liver cirrhosis. Current good selection criteria of LT for HCC are the Milan criteria: 1 HCC nodule ≤5 cm in diameter or 3 nodules ≤3 cm. By restricting LT to patients within the Milan criteria, the 4-year disease-free survival rate was more than 80%, which is comparable to that of a transplant candidate without HCC. However, there are serious limitations for the wider application of LT for HCC: (1) organ shortage, (2) risk to a live donor, (3) high cost, and (4) lifelong immunosuppression. For this reason, for a patient with early stage HCC and with Child A cirrhosis in whom partial hepatectomy is possible, the choice of primary treatment with curative intent is still under debate.

Thrombosis confined to the portal vein is not a contraindication for living donor liver transplantation

BackgroundThere is a lack of agreement regarding preexisting portal vein thrombosis (PVT) in patients undergoing living donor liver transplantation (LDLT). We report the results of a single-center study to determine the impact of PVT on outcomes of adult LDLT recipients.MethodsOf 133 cases of adult LDLT performed between January 2000 and December 2004, a thrombectomy was performed on 22 patients (16.5%) with PVT during the transplant procedure. One hundred eleven patients without PVT (group 1) were compared with those with a thrombosis confined to the portal vein (group 2; nxa0=xa015) and patients with the thrombosis beyond the portal vein (group 3; nxa0=xa07).ResultsThe sensitivities of Doppler ultrasound and CT in detecting PVT were 50 and 63.6%. A prior history of variceal bleeding (ORxa0=xa010.6, pxa0=xa00.002) and surgical shunt surgery (ORxa0=xa028.1, pxa0=xa00.044) were found to be an independent risk factors for PVT. The rate of postoperative PVT was significantly higher in patients with PVT than in those without (18.2 vs. 2.7%; pxa0=xa00.014). In particular, the rethrombosis rate in group 3 was 28.6%. The actuarial 3-year patient survival rate in PVT patients (73.6%) was similar to that of the non-PVT patients (85.3%; pxa0=xa00.351). However, the actuarial 3-year patient survival rate in group 3 was 38.1%, which was significantly lower than that in groups 1 and 2 (pxa0=xa00.006).ConclusionA thrombosis confined to the portal vein per se should not be considered a contraindication for LDLT.

Pediatric Liver Transplantation Outcomes in Korea

Pediatric liver transplantation is the standard of care for treatment of liver failure in children. The aim of this study was to identify the characteristics of pediatric liver transplantation in centers located in Korea and determine factors that influence outcomes. This retrospective study was performed using data from between 1988 and 2010 and included all recipients 18 yr old and younger who underwent pediatric liver transplantation in Korea during that period. Our data sources were hospital medical records and the outcome measure was overall patient survival. Univariate and multivariate statistical analyses were undertaken using the Cox proportional hazards model. Five hundred and thirty-four pediatric liver transplantations were performed in 502 children. Median age and average pediatric end-stage liver disease (PELD) score were 20 months and 18 point, respectively. Biliary atresia (57.7%, 308/534) was the most common cause of liver disease. Eighty-two (15.3%) were deceased donor liver transplantations and 454 (84.7%) were living donor liver transplantations. Retransplantation was performed in 32 cases (6%). Overall, 1-, 5-, and 10-yr patient survival rates were 87.8%, 82.2%, and 78.1%, respectively. In multivariate analysis, independent significant predictors of poor patient survival were chronic rejection and retransplantation. This study presents the epidemiologic data for nearly all pediatric liver transplantation in Korea and shows that the independent prognostic factors in patient survival are chronic rejection and retransplantation.

Quantification of hepatic macrosteatosis in living, related liver donors using T1-independent, T2*-corrected chemical shift MRI.

To evaluate the diagnostic implications of the iterative decomposition of water and fat using echo‐asymmetry and the least‐squares estimation (IDEAL) technique to detect hepatic steatosis (HS) in potential liver donors using histopathology as the reference standard.

Shear wave elastography in the evaluation of rejection or recurrent hepatitis after liver transplantation

AbstractObjectivesTo determine whether shear wave elastography (SWE) would be useful in evaluating the presence of rejection or recurrent hepatitis for post-liver transplantation (LT) follow-up.MethodsThis retrospective study was approved by our Institutional Review Board and informed consent was waived. Two hundred sixteen liver recipients and 37 liver donors received SWE and concurrent liver biopsy. Of the liver recipients, 142 patients underwent SWE > 4xa0weeks after the LT (group 1) and 74 patients underwent SWE ≤ 4xa0weeks after the LT (group 2). Liver stiffness (LS) was compared among groups of donor, no rejection, acute rejection and recurrent hepatitis.ResultsIn group 1, LS was higher in patients with rejection or hepatitis than in patients without rejection or indefinite rejection (12.29u2009±u20098.13xa0kPa vs. 6.33u2009±u20092.10xa0kPa, respectively, Pu2009<u20090.001). In group 2, there was no difference in LS between patients with rejection (nu2009=u20098) and those without rejection (nu2009=u200961; Pu2009>u20090.05). The liver recipients without rejection or hepatitis in both groups showed significantly higher LS than the liver donors (Pu2009<u20090.001).ConclusionsSWE may be used as a non-invasive complementary tool to detect rejection or recurrent hepatitis at follow-up > 4xa0weeks after the LT.Key Points• Shear wave ultrasound elastography may be useful at follow-up after liver transplantationn • Rejection or hepatitis can be predicted >4xa0weeks after liver transplantationn • Normal liver grafts are stiffer than normal liver.

Factors affecting the apparent clearance of tacrolimus in Korean adult liver transplant recipients.

Study Objective. To identify the factors affecting tacrolimus apparent total body clearance (Cl/F [F = bioavailability]) in adult liver transplant recipients.

The Right Small-for-Size Graft Results in Better Outcomes than the Left Small-for-Size Graft in Adult-to-Adult Living Donor Liver Transplantation

BackgroundThe recent outcome of adult-to-adult living donor liver transplantation (ALDLT) using small-for-size grafts (SFSGs; GRWR <0.8%) has been excellent after right grafts were exclusively used in large-volume ALDLT centers.MethodsWe compared the outcome of ALDLTs using 11 right SFSGs (group R) with that using 18 left SFSGs (group L) of our center. The dysfunction of graft was defined dysfunction as hyperbilirubinemia (>5xa0mg/dl), prolonged prothrombin time (>2 INR), or uncontrolled ascites (>1,000xa0ml/day) on 3 consecutive days in posttransplant 7xa0days, and the dysfunction score (DS; the sum of points given per each sign) of the graft was used to describe the SFSG dysfunction severity.ResultsThe pretransplant recipient status was similar between the groups, but the 1-year mortality rate was 0% in group R and 33.3% (nxa0=xa06) in group L (pxa0=xa00.038). The ICU stay was longer in group L (20xa0days) than in group R (11xa0days; pxa0=xa00.004). Hyperbilirubinemia in group R vs. L was noted in 54.5% vs. 50%, prolonged prothrombin time in 18.2% vs. 50%, and uncontrolled ascites in 54.5% vs. 100%. The DS was lower in group R than in group L (1.3 vs. 2; pxa0=xa00.007). The DS was zero in four right liver recipients. On multivariate analysis, the only factor affecting DS was the graft side.ConclusionThe clinical signs of SFSG dysfunction were less arduous and there was no 1-year mortality in cases in group R. Therefore, the right SFSG may be used for ALDLT in the future base on the transplant center’s experience.