The healing pattern of a 4 mm proximal infrabony defect was not significantly different from a 2 mm defect adjacent to dental implant in a canine mandible.

PURPOSE: The purpose of this study was to evaluate and compare the healing patterns of 2-mm and 4-mm proximal infrabony defects adjacent to dental implants in canine mandibles. METHODS: Four male beagles were used. Two groups were created: a 2-mm group (n=4) and a 4-mm group (n=4) depending on the horizontal dimension of proximal infrabony defects adjacent to implants. Bone healing patterns between the 2 groups were evaluated and compared at 8 and 16 weeks using radiographic, histological, histomorphometric, and fluorescent labelling analyses. RESULTS: According to microcomputed tomography, the median bone volume fraction, bone mineral density, and the percentage of radiographic distance from the defect bottom to the most coronal bone-to-implant contact (radio-mcBIC) were 32.9%, 0.6 g/cm3, and 73.7% (8 weeks) and 45.7%, 0.7 g/cm3, and 76.0% (16 weeks) in the 2-mm group and 57.7%, 0.8 g/cm3, and 75.7% (8 weeks) and 50.9%, 0.8 g/cm3, and 74.7% (16 weeks) in the 4-mm group, respectively. According to histomorphometry, the median bone area fraction, mcBIC and the percentage of BIC amounted to 36.7%, 3.4 mm, and 58.4% (8 weeks) and 49.2%, 3.4 mm, and 70.2% (16 weeks) in the 2-mm group and 50.0%, 3.0 mm, and 64.8% (8 weeks) and 55.7%, 3.0 mm, and 69.6% (16 weeks) in the 4-mm group, respectively. No statistically significant differences were found between the groups for any variables (P>0.05). CONCLUSIONS: The proximal defects that measured 2 mm and 4 mm showed similar healing patterns at 8 and 16 weeks, and the top of bone formation in the defects was substantially limited to a maximum of 1.6 mm below the implant shoulder in both groups.

Diagnostic and prognostic impact of fluorodeoxyglucose-positron emission tomography in diagnosing intraductal papillary neoplasms of the bile duct of the liver.

Purpose: Malignant intraductal papillary neoplasm of the bile duct of the liver (IPNB-L) cannot readily be diagnosed through preoperative CT or MRI, but fluorodeoxyglucose (FDG)-PET is a viable alternative. This study evaluated the diagnostic and prognostic impacts of FDG-PET in patients with IPNB-L. Methods: This was a retrospective single-center study of 101 IPNB-L patients who underwent hepatectomy between 2010 and 2019. Results: Mean age was 64.4 ± 8.3 years and 76 (75.2%) were male. Anatomical hepatic resection was performed in 99 (98.0%). Concurrent bile duct resection and pancreaticoduodenectomy were performed in 41 (40.6%) and 1 (1.0%), respectively. R0 and R1 resections were performed in 88 (87.1%) and 13 (12.9%), respectively. Low-grade intraepithelial neoplasia and high-grade neoplasia/invasive carcinoma were diagnosed in 19 (18.8%) and 82 (81.2%), respectively. Median FDG-PET maximal standardized uptake values (SUVmax) in low-grade neoplasia and high-grade neoplasia/carcinoma were 3.6 (range, 1.7-7.6) and 5.2 (range, 1.5-18.7) (P = 0.019), respectively. Receiver operating characteristic curve analysis of SUVmax showed area under the curve of 0.674, with sensitivity of 84.2% and specificity of 47.4% at SUVmax cutoff of 3.0. This cutoff had no significant influence on tumor recurrence (P = 0.832) or patient survival (P = 0.996) in patients with IPNB-L of high-grade neoplasia or invasive carcinoma. Conclusion: IPNB-L is a rare type of biliary neoplasm and encompasses a histological spectrum ranging from benign disease to invasive carcinoma. An FDG-PET SUVmax cutoff of 3.0 appears to effectively discern high-grade neoplasia/carcinoma from low-grade neoplasia, which will assist with the surgical strategy for these cases.

Fates of retained hepatic segment IV and its prognostic impact in adult split liver transplantation using an extended right liver graft.

PURPOSE: When splitting a liver for adult and pediatric graft recipients, the retained left medial section (S4) will undergo ischemic necrosis and the right trisection graft becomes an extended right liver (ERL) graft. We investigated the fates of the retained S4 and its prognostic impact in adult split liver transplantation (SLT) using an ERL graft. METHODS: This was a retrospective analysis of 25 adult SLT recipients who received split ERL grafts. RESULTS: The mean model for end-stage liver disease (MELD) score was 27.3 ± 10.9 and graft-recipient weight ratio (GRWR) was 1.98 ± 0.44. The mean donor age was 26.5 ± 7.7 years. The split ERL graft weight was 1,181.5 ± 252.8 g, which resulted in a mean GRWR of 1.98 ± 0.44. Computed tomography of the retained S4 parenchyma revealed small ischemic necrosis in 16 patients (64.0%) and large ischemic necrosis in the remaining 9 patients (36.0%). No S4-associated biliary complications were developed. The mean GRWR was 1.87 ± 0.43 in the 9 patients with large ischemic necrosis and 2.10 ± 0.44 in the 15 cases with small ischemic necrosis (P = 0.283). The retained S4 parenchyma showed gradual atrophy on follow-up imaging studies. The amount of S4 ischemic necrosis was not associated with graft (P = 0.592) or patient (P = 0.243) survival. A MELD score of >30 and pretransplant ventilator support were associated with inferior outcomes. CONCLUSION: The amount of S4 ischemic necrosis is not a prognostic factor in adult SLT recipients, probably due to a sufficiently large GRWR.

Salvage aorto-hepatic jump graft for hepatic artery thrombosis following living donor liver transplantation: a case report with 10-year follow-up.

Hepatic artery thrombosis (HAT) following living donor liver transplantation (LDLT) is a lethal complication. We present the case of a patient who underwent salvage redo hepatic artery reconstruction using an aorto-hepatic jump graft because of HAT following LDLT. A 64-year-old female patient diagnosed with hepatitis C virus-associated liver cirrhosis and hepatocellular carcinoma underwent salvage LDLT using a modified right liver graft. Partial graft infarct was identified at posttransplant day 4, and by day 9, it had spread. Celiac arteriography showed complete occlusion of the graft hepatic artery. We performed redo hepatic artery reconstruction using a fresh iliofemoral artery homograft 10 days after the LDLT operation because such a vessel homograft was available at our institutional tissue bank. The infrarenal aorta was dissected and an iliofemoral artery graft was anastomosed. Soon after hepatic artery revascularization, liver function progressively improved, and the infarct area at the liver graft was reduced. The patient has been doing well for 10 years without any vascular complications. In conclusion, our experience with this case suggests that salvage redo hepatic artery reconstruction using an aorto-hepatic jump graft is a feasible option to treat HAT following LDLT, as in deceased donor liver transplantation.

Over 500 Liver Transplants Including More Than 400 Living-Donor Liver Transplants in 2019 at Asan Medical Center.

BACKGROUND: More than 400 liver transplants were performed at Asan Medical Center (AMC) in 2011, and over 500 liver transplants including 420 living-donor liver transplants (LDLTs) were performed in 2019. Herein, we report the methodology of these procedures. METHODS: Since the first adult LDLTs at AMC using the left and right lobes were successfully performed, various innovative techniques and approaches have been developed: modified right lobe, dual graft, donor exchange for ABO incompatibility, expansion of indications and no-touch techniques for hepatocellular carcinoma, intraoperative cine-portogram and additional intervention for large collaterals, management of portal vein thrombosis (PVT) and stenosis, salvage LDLT after major hepatectomy, and timely LDLT for patients with acute-on-chronic liver failure. RESULTS: Four hundred twenty LDLTs in 403 adult and 17 pediatric patients and 85 deceased-donor liver transplants in 74 adult and 11 pediatric patients were performed. The number of deceased-donor liver transplants remained constant since 2011, but the number of LDLTs increased steadily. One hundred thirty patients (25.7%) required urgent liver transplantations and 24 patients with acute-on-chronic liver failure underwent LDLT. PVT including grade 1,2,3, and 4 was reported in 91 patients (18.0%), and Yerdel's grade 2, 3, and 4 PVT was reported in 47 patients (51.6%); all patients with PVT were successfully treated. Adult LDLTs for hepatocellular carcinoma and ABO incompatibility accounted for 52.6% and 24.3% of the cases, respectively. In-hospital mortality in 2019 was 2.97%. CONCLUSION: Continual efforts to overcome challenging problems in LDLT with various innovations and dedication of the team members during the perioperative period to improve patient outcomes were crucial in increasing the number of liver transplantations at Asan Medical Center.

Life-Threatening Portal Flow Steal Reappearing Under Increased Intrahepatic Vascular Resistance After Living Donor Liver Transplantation.

Maintenance of adequate portal inflow is crucial for graft regeneration in adult living donor liver transplantation (ALDLT) to allow the recipients to meet their early metabolic demands. A persistent large spontaneous portosystemic shunt can divert portal flow away from the liver graft, leading to impaired or delayed graft regeneration and subsequent graft failure. The importance of obliterating huge portosystemic shunt during liver transplantation is obvious for successful ALDLT. However, in partial liver graft with a relatively small graft-to-recipient weight ratio (GRWR) (compared with deceased donor whole graft liver transplantation), even the persisting small portosystemic shunt may result in repeated portal flow steal when a liver graft faces increased intrahepatic vascular resistance caused by rejection or graft congestion with hepatic venous outflow stenosis. We present 2 complicated cases of reappearing portal flow steal that were derived from the remaining small portosystemic shunt under the increased vascular resistance of the liver graft, even after interruption of a large portosystemic shunt during ALDLT. Because ALDLT is always a partial liver graft, even when GRWR is over 1%, it is much more vulnerable to hemodynamic changes in portal flow by rejection or graft congestion by hepatic venous outflow obstruction. Therefore, a comprehensive understanding of complex portosystemic shunt and complete reinterruption of reappearing portosystemic shunt, even though small and insignificant, during ALDLT is important for graft salvage procedures before irreversible liver graft damage.

Refined surgical techniques to improve the patency of cryopreserved iliac artery homografts for middle hepatic vein reconstruction during living donor liver transplantation.

PURPOSE: A cryopreserved iliac artery homograft (IAH) has not been considered suitable for middle hepatic vein (MHV) reconstruction during living donor liver transplantation (LDLT), primarily due to the low patency from its small diameter. We revised our surgical techniques for MHV reconstruction using an IAH to improve its patency. METHODS: This study analyzed the causes of early conduit occlusion and developed revised techniques to address this that had clinical application. RESULTS: The potential risk factors for early conduit occlusion were the small IAH size, small graft in the segment V vein (V5) and segment VIII vein (V8) opening, and small recipient MHV-left hepatic vein stump. These factors were reflected to our revised surgical methods which included endarterectomy of the atherosclerotic plaque, unification of the internal and external iliac artery branches for large V5, and branch-patch arterioplasty for large V8. IAH endarterectomy, branch unification technique, and branch-patch arterioplasty were applied to 8, 5, and 5 patients, respectively and resulted in 1-month occlusion rates of 37.5%, 20.0%, and 40.0%, respectively. The overall patency rates of the IAH-MHV conduits in our 18 patients were 66.7% at 1 month, 38.9% at 3 months, and 33.3% at 1 year. CONCLUSION: Our refined MHV reconstruction using an IAH improved short-term MHV conduit patency, but did not effectively prevent early conduit occlusion, particularly with a small- or medium-sized IAH. Individualized reconstruction designs during LDLT operation are needed when an IAH is used for a modified right liver graft.

Comparison of Periodontopathic Bacterial Profiles of Different Periodontal Disease Severity Using Multiplex Real-Time Polymerase Chain Reaction.

Periodontopathic bacteria are known to have a pivotal role in the pathogenesis of periodontitis. The aim of the study was to quantitatively compare bacterial profile of patients with different severity of periodontal disease using samples from mouthwash and the subgingival area. Further analysis was performed to evaluate the correlation between mouthwash and two subgingival sampling methods: paperpoint and gingival retraction cord; 114 subjects enrolled in the study, and were divided equally into three groups according to disease severity. Mouthwash and subgingival sampling were conducted, and the samples were quantitatively analyzed for 11 target periodontopathic bacteria using multiplex real-time PCR. There were statistically significant differences in bacterial counts and prevalence of several species between the study groups. Mouthwash sampling showed significant correlations with two different subgingival sampling methods in regard to the detection of several bacteria (e.g., ρ = 0.793 for Porphyromonas gingivalis in severe periodontitis), implying that mouthwash sampling can reflect subgingival microbiota. However, the correlation was more prominent as disease severity increased. Although bacteria in mouthwash have potential to become a biomarker, it may be more suitable for the diagnosis of severe periodontitis, rather than early diagnosis. Further research is required for the discovery of biomarkers for early diagnosis of periodontitis.

Prognosis of Split Liver Transplantation Compared with Whole Liver Transplantation in Adult Patients: Single-center Results under the Korean MELD Score-based Allocation Policy.

BACKGROUND: Split liver transplantation (SLT) has been occasionally performed in Korea. This study compared the incidence and prognosis of SLT with whole liver transplantation (WLT) in adult patients. METHODS: Between June 2016 and November 2019, 242 adult patients underwent a total of 256 deceased donor liver transplantation operations. SLT was performed in 7 patients (2.9%). RESULTS: The mean age of SLT donors was 29.7 ± 7.4 years, and the mean age of recipients was 55.7 ± 10.6 years, with the latter having a mean model for end-stage liver disease score of 34.6 ± 3.1. Mean split right liver graft weight was 1,228.6 ± 149.7 g and mean graft-recipient weight ratio was 1.97 ± 0.39. Of the seven SLT recipients, Korean Network for Organ Sharing (KONOS) status was one in status 1, one in status 2 and five in status 3. The graft (P = 0.72) and patient (P = 0.84) survival rates were comparable in the SLT and WLT groups. Following propensity score matching, graft (P = 0.61) and patient (P = 0.91) survival rates remained comparable in the two groups. Univariate analysis showed that pretransplant ventilator support and renal replacement therapy were significantly associated with patient survival, whereas KONOS status category and primary liver diseases were not. Multivariate analysis showed that pretransplant ventilator support was an independent risk factor for patient survival. CONCLUSION: Survival outcomes were similar in adult SLT and WLT recipients, probably due to selection of high-quality grafts and low-risk recipients. Prudent selection of donors and adult recipients for SLT may expand the liver graft pool for pediatric patients without affecting outcomes in adults undergoing SLT.

Validation of prognostic impact of ADV score for resection of hepatocellular carcinoma: analysis using Korea Liver Cancer Registry Database.

PURPOSE: We aimed to validate the prognostic predictive power of ADV score (α-FP-des-γ-carboxyprothrombin [DCP]-tumor volume [TV] score, calculated as α-FP [ng/mL] × DCP [mAU/mL] × TV [mL] and expressed in log10) for predicting patient survival after resection of hepatocellular carcinoma (HCC). METHODS: This study included 1,390 patients with HCC registered in the Korea Liver Cancer Registry. Patients underwent hepatic resection between 2008 and 2012 and were followed up until December 2016. They were divided into 4 groups according to the number of tumors and preoperative treatment. RESULTS: There was no significant correlation among α-FP, DCP, and TV values (r2 ≤ 0.04, P < 0.001). In group 1 with single treatment-naive tumor (n = 1,154), patient stratification with postoperative ADV 1log-interval and cutoffs of 5log, 7log, and 10log showed great prognostic contrast (P < 0.001). In group 2 with multiple treatment-naive tumors (n = 170), patient stratification with postoperative ADV 1log-interval and above-mentioned 3 cutoffs also showed great prognostic contrast (P < 0.001). In group 3 (n = 50) and group 4 (n = 16) with preoperative-treated tumors, patient stratification with postoperative ADV 1log-interval and above-mentioned 3 cutoffs showed noticeable prognostic contrast (P ≤ 0.031). Preoperative ADV score based on preoperative findings also showed great prognostic contrast in 1,106 patients preoperatively diagnosed as having single treatment-naive tumor (P < 0.001). Confining patients to tumor-node-metastasis stages I and II (n = 1,072) as well as Barcelona Clinic Liver Cancer stage 0 and A (n = 862), postoperative ADV cutoffs showed further prognostic stratification. CONCLUSION: This validation study strongly suggests that ADV score is an integrated surrogate marker for postresection prognosis in patients with HCC.

Living donor liver transplantation for unresectable colorectal liver metastasis: Report of a case with 13-year follow-up without recurrence.

The feasibility of liver transplantation (LT) for colorectal liver metastasis (CRLM) is still under investigation with only a limited number of LT cases in literature. CRLM is the most common type of liver metastasis, but it was considered as a contraindication to LT for a long time because of poor outcomes. We presented a case of living donor liver transplantation (LDLT) performed in a patient with liver cirrhosis and CRLM. The patient was a 49-year-old female with sigmoid colon cancer and synchronous multiple CRLM. She underwent anterior resection for sigmoid colon cancer and 7 sessions of chemotherapy for CRLM. She suffered from esophageal varix bleeding due to chemotherapy-associated liver cirrhosis. Because of liver cirrhosis and multiple CRLM, the patient underwent LDLT operation using a modified right lobe graft. Serum chorioembryonic antigen level was 220 ng/mL at LT. Explant liver pathology showed multiple metastatic adenocarcinomas of colonic origin, up to 4.7 cm in the greatest dimension. The patient did not receive any specific anti-tumor treatment after LT. She is doing well without any tumor recurrence to date for more than 13 years after the LDLT operation. The experience on our case and literature review suggest that CRLM is not always contraindicated for LT because some selected patients showed improved long-term survival outcomes.

Living donor liver transplantation for diffuse biliary papillomatosis with malignant change: A case report with 10-year follow-up.

Biliary papillomatosis is a rare disease of the biliary tract. In this study, we present a case of a male patient with biliary papillomatosis with malignant change who underwent living donor liver transplantation (LDLT). The 49-year-old man was admitted due to intrahepatic ductal mass, which was finally diagnosed as biliary papillomatosis. It was initially treated by photodynamic therapy, but LDLT was planned due to low efficacy of photodynamic therapy. LDLT was performed with a right liver graft from his son. The pathology report revealed intraductal papillary neoplasm with associated invasive carcinoma. He recovered uneventfully. Although the distal bile duct resection margin was free of tumor, the risk of tumor recurrence at the remnant intrahepatic bile duct still remained. Therefore, staged pylorus-preserving pancreatoduodenectomy was planned. However, after 3 months, he was readmitted due to retropancreatic abscess. It took 6 months to control the intractable retropancreatic abscess. Due to late development of retropancreatic abscess and its slow recovery, staged pancreatoduodenectomy was no longer considered. The patient recovered complete at 1 year posttransplant without any evidence of disease recurrence. After 5 years posttransplant, lung metastasis developed and pulmonary metastasectomy was performed three times. No further recurrence developed during the last 3 years to date, and the patient currently is alive, 10 years after the LDLT. Experience on our case and literature review suggest that patients with biliary papillomatosis with or without malignant transformation are selectively indicated for liver transplantation.

Management of intractable pancreatic leak from iatrogenic pancreatic duct injury following resection of choledochal cyst in an adult patient.

Iatrogenic pancreatic duct injury can occur during resection of the choledochal cyst (CC). We herein present a case of postoperative pancreatic fistula (POPF) developed after resection of the CC in an adult patient with variant anomalous union of pancreatobiliary duct. The 55-year-old female patient underwent surgery after the diagnosis of CC-associated gallbladder cancer. During surgery, the CC mass was accidentally pulled out, by which the intrapancreatic CC portion was torn out from the main pancreatic duct. Since the pancreatic duct stump was not identified due to its small size, repair was not possible. The excavated defect at the pancreas head was closed securely combined with insertion of multiple drains. Postoperative POPF and peripancreatic fluid collection developed and the patient had to be fasted for 4 weeks. She was first discharged at 6 weeks after surgery. At 10 weeks, she was readmitted due to progression of peripancreatic fluid collection, which was controlled by percutaneous drain insertion. At 6 months, she was readmitted again due to repeated progression of peripancreatic fluid collection, which were controlled by endoscopic transmural duodenocystostomy. It took 8 months to resolve the pancreatic duct injury-associated pancreatitis. The experience in this case suggests that iatrogenic pancreatic duct injury during resection of CC can induce catastrophic complications, thus special attention should be paid to prevent pancreatic duct injury.

Pretransplant Hepatic Malignancy Increases Risk of De Novo Malignancy after Liver Transplantation.

BACKGROUND: Hepatocellular carcinoma (HCC) recurrence and development of de novo malignancy (DNM) after liver transplantation (LT) are the major causes of late recipient death. METHODS: We analyzed the incidence of extrahepatic DNM following living donor LT according to the status of pretransplant hepatic malignancy. We selected 2,076 adult patients who underwent primary LDLT during 7 years from January 2010 to December 2016. RESULTS: The pretransplant hepatic malignancy group (n = 1,012) showed 45 cases (4.4%) of the following extrahepatic DNMs: posttransplant lymphoproliferative disease (PTLD) in 10; lung cancer in 10; stomach cancer in 6; colorectal cancer in 5; urinary bladder cancer in 3; and other cancers in 11. The pretransplant no hepatic malignancy group (n = 1,064) showed 25 cases (2.3%) of the following extrahepatic DNMs: colorectal cancer in 3; stomach cancer in 3; leukemia in 3; lung cancer in 3; PTLD in 2; prostate cancer in 2; and other cancers in 9. Incidences of extrahepatic DNM in the pretransplant hepatic malignancy and no hepatic malignancy groups were as follows: 1.1% and 0.5% at 1 year, 3.2% and 2.0% at 3 years, 4.6% and 2.5% at 5 years, and 5.4% and 2.8% at 8 years, respectively (P = 0.006). Their overall patient survival rates were as follows: 97.3% and 97.2% at 1 year, 91.6% and 95.9% at 3 years, 89.8% and 95.4% at 5 years, and 89.2% and 95.4% at 8 years, respectively (P < 0.001). Pretransplant hepatic malignancy was the only significant risk factor for posttransplant extrahepatic DNM. CONCLUSION: Our results suggest that patients who had pretransplant hepatic malignancy be followed up more strictly because they have a potential risk of primary hepatic malignancy recurrence as well as a higher risk of extrahepatic DNM than patients without pretransplant hepatic malignancy.

Is renal replacement therapy necessary in deceased donor liver transplantation candidates with hepatorenal syndrome?: a 2-year experience at a high-volume center.

PURPOSE: Hepatorenal syndrome (HRS) is a fatal complication in patients with end-stage liver disease awaiting liver transplantation (LT). HRS often develops in patients with high model for end-stage liver disease (MELD) score. This study investigated the outcomes of peritransplant management of HRS in a high-volume LT center in Korea for 2 years. METHODS: A total of 157 recipients that deceased donor liver transplantation (DDLT) from January 2017 to December 2018 were included. In-hospital mortality (IHM) was analyzed in relation to pre- and posttransplant application of renal replacement therapy (RRT). RESULTS: Primary diagnoses for DDLT were alcoholic liver disease (n = 61), HBV-associated liver cirrhosis (n = 48), retransplantation for chronic graft failure (n = 24), and others (n = 24). Mean MELD score was 34.6 ± 6.2 with 72 patients at Korean Network for Organ Sharing MELD status 2 (45.9%), 43 at status 3 (27.4%), 36 at status 4 (22.9%), and 6 at status 5 (3.8%). Pretransplant RRT was performed in 16 patients (10.2%) that did not show IHM. Posttransplant RRT was performed in 69 patients (44.0%), for whom IHM incidence was 15.9%. In 53 patients that had undergone de novo posttransplant RRT, IHM incidence increased to 20.8%. IHM in the 88 patients not requiring RRT was 2.3%. CONCLUSION: The majority of adult DDLT recipients in Korean MELD score-based allocation system have very high MELD scores, which is often associated with HRS. Pretransplant RRT appears to improve posttransplant survival outcomes. We thereby recommend that, if indicated, pretransplant RRT be performed while awaiting DDLT.

Prolonged hepatic inflow occlusion to reduce bleeding during recipient hepatectomy in living donor liver transplantation.

Background: Living donor liver transplantation (LDLT) causes bleeding in recipients during the careful preservation of most perihilar structures during this surgery. This case-control study aimed to analyze the effect of prolonged hepatic inflow occlusion (PHIO) when applied during recipient hepatectomy in LDLT. Methods: The study group comprised patients who underwent PHIO with Model for End-Stage Liver Disease (MELD) scores ranging from 26 to 35 (n=20). The following two control groups were selected according to their MELD scores: the low-MELD score group (MELD scores of 15-20, n=40) and the high-MELD score group (MELD scores of 26-35, n=40). Total dissection time for hepatic mobilization and dissection and blood loss during these procedures were compared between the two groups. Results: In the PHIO study group, mean total dissection time and mean PHIO duration were 226.3±59.4 and 68.2±19.1 minutes, respectively. Twelve patients underwent PHIO twice, and the other eight patients underwent PHIO once. The low-MELD score control group and the PHIO study group showed similar dissection duration (216.0±43.9 vs. 226.3±59.4 minutes, P=0.82) and similar blood loss volume during dissection (2,112.5±1,614.9 vs. 2,350.0±951.9 mL, P=0.17). The high-MELD score control group and the PHIO study group showed similar dissection duration (241.0±41.9 vs. 226.3±59.4 minutes, P=0.71), but the PHIO group showed a significantly lower blood loss during dissection than the high-MELD score group (2,350.0±951.9 vs. 2,815.0±1,813.9 mL, P=0.002). During and after PHIO, no adverse complication was observed, except for transient splanchnic congestion. Conclusions: Our findings suggest that PHIO is a simple effective method to reduce intraoperative bleeding during hepatic mobilization and dissection during LDLT operation requiring difficult dissection.

Changes in the indications for living donor liver transplantation: single-institution experience of 3,145 cases over 10 years.

Background: To understand the changing demands and recent trends in the indications for living donor liver transplantation (LDLT), the present study aimed to analyze the indications for LDLT performed in a high-volume transplantation center over 10 years. Methods: The liver transplantation database at our institution was searched to identify patients who underwent LDLT during a 10-year period from January 2008 to December 2017. The study subjects (n=3,145) were divided into two groups: adult patients (n=3,019, 92.7%) and pediatric patients (n=126, 3.9%). Results: In the adult recipients, the primary diagnoses were hepatitis B virus (HBV)-associated liver cirrhosis (n=1,898, 62.9%), alcoholic liver disease (n=482, 16.0%), hepatitis C virus-associated cirrhosis (n=203, 6.7%), acute liver failure (n=127, n=4.2%), and other diseases (n=157, 5.2%). The mean Model for End-Stage Liver Disease score was 15.6±8.8 (range, 6-40). The proportion of patients with HBV-associated liver disease gradually decreased, but the proportion of those with alcoholic liver disease increased. Hepatocellular carcinoma (HCC) was diagnosed in 1,467 patients (48.6%). The mean proportion of patients with HCC was 63.1% among those with HBV-associated liver disease. In pediatric recipients, the primary diagnoses were biliary atresia (n=51, 40.5%), liver failure of various causes (n=37, 29.4%), metabolic disease (n=22, 17.5%), hepatoblastoma (n=12, 9.5%), and infectious diseases (n=4, 3.2%). Conclusions: Our results showed that there were some significant changes in the indications of LDLT. We believe that our results may reflect the real changes in the indications of LDLT and they will be useful for predicting further changes in the future.

Hemashield Vascular Graft Is a Preferable Prosthetic Graft for Middle Hepatic Vein Reconstruction in Living Donor Liver Transplantation.

BACKGROUND Because of the supply shortage for homologous vein allografts, we previously used ringed Gore-Tex vascular grafts for middle hepatic vein (MHV) reconstruction in living donor liver transplantation. However, owing to the subsequent unavailability of ringed Gore-Tex grafts, we replaced them with Hemashield vascular grafts. This study aimed to compare the patency of Hemashield grafts with that of ringed Gore-Tex grafts. MATERIAL AND METHODS This was a retrospective double-arm study between the study group that used Hemashield grafts (n=63) and the historical control group that used ringed Gore-Tex grafts (n=126). RESULTS In the Gore-Tex and Hemashield groups, mean age was 53.1±6.2 and 54.3±10.4 years; model for end-stage liver disease score was 16.5±8.3 and 17.5±9.9; and graft-recipient weight ratio was 1.11±0.23 and 1.12±0.25, respectively. In the Gore-Tex graft group, V5 reconstruction was done in single (n=107, 84.9%), double (n=17, 13.5%), and none (n=2, 1.6%). V8 reconstruction was done in single (n=95, 75.4%), double (n=1, 0.8%), and none (n=30, 23.8%). In the Hemashield group, V5 reconstruction was done in single (n=43, 68.3%), double (n=19, 30.2%), and triple (n=1, 1.6%). V8 reconstruction was done in single (n=45, 71.4%), double (n=9, 14.3%), and none (n=9, 14.3%). One-year conduit patency rates in the Gore-Tex and Hemashield groups were 54.8% and 71.6%, respectively (p=0.048). CONCLUSIONS MHV reconstruction using Hemashield vascular grafts demonstrated higher short-term patency rates than those associated with ringed Gore-Tex vascular grafts. We suggest that the Hemashield vascular graft is one of the best prosthetic materials for MHV reconstruction.

Determination of Hepatitis B Immunoglobulin Infusion Interval Using Pharmacokinetic Half-life Simulation for Posttransplant Hepatitis B Prophylaxis.

BACKGROUND: Prophylaxis for hepatitis B virus (HBV) recurrence is essential after liver transplantation (LT) in HBV-associated recipients. This study established an individualized HBV prophylaxis protocol, through optimization of hepatitis B immunoglobulin (HBIG) administration, with application of simulative half-life (SHL). METHODS: This study involved five parts: Part 1 developed the SHL estimation method with 20 patients; Parts 2 and 3 assessed the SHL variability and developed a simulation model to apply SHL in 100 patients; Part 4 validated the simulation model in 114 patients, and Part 5 was a cross-sectional study on the current status of HBIG infusion intervals in 660 patients. RESULTS: In Part 1, infusion of 10,000 IU HBIG induced add-on rise hepatitis B surface antibody (anti-HBs) titer of 5,252.5 ± 873.7 IU/L, which was 4.4% lower than actual measurement. Mean SHL of 20.0 ± 3.7 days was 2.2% longer than actual measurement. In Part 2, the medians of the intra- and inter-individual coefficient of variation in SHL were 13.5% and 18.5%, respectively. Pretransplant HBV DNA load and posttransplant antiviral therapy did not affect SHL. In Part 3, a simulation model was developed to determine the interval of HBIG infusion, by using SHL. In Part 4, all 114 patients were successfully managed with regular HBIG infusion intervals of ≥ 8 weeks, and the interval was prolonged to ≥ 12 weeks in 89.4%, with a target trough anti-HBs titer ≥ 200 IU/L. In Part 5, 47.4% of our patients received HBIG excessively, at a target trough titer of 500 IU/L. CONCLUSION: SHL estimation using only clinically available parameters seems to be reliably accurate when compared with actual measurements. We believe that SHL estimation is helpful to establish a personalized HBV prophylaxis protocol for optimizing HBIG administration.

Pediatric living donor liver transplantation with homograft replacement of retrohepatic inferior vena cava for advanced hepatoblastoma.

Replacement of the retrohepatic inferior vena cava (IVC) after concurrent resection of IVC and hepatocellular carcinoma-containing liver is settled as a feasible living donor liver transplantation (LDLT) technique to cope with tumors around the IVC. This technique makes LDLT comparable to deceased-donor liver transplantation (DDLT). In the current Korean setting, the common substitute for IVC is a Dacron graft for adult recipients. In contrast, such a synthetic graft cannot be used for pediatric patients because of ongoing growth. We present one pediatric LDLT case with IVC homograft replacement for advanced hepatoblastoma. The patient was a 8 year-old boy suffering from large multiple hepatoblastomas. The tumors encroached the retrohepatic IVC. Thus there was high risk of residual tumor cells at the IVC, if it was preserved. Thus, we decided to replace IVC at the time of LDLT. After waiting for >1 month, we finally obtained cold-stored IVC homograft and LDLT was performed with the mother's left liver. A 4 cm-long IVC allograft was anastomosed at the back table. The left liver graft with IVC interposition was implanted along standard procedure similar to DDLT. The patient recovered uneventfully and is undergoing scheduled adjuvant chemotherapy. We have performed >20 cases of IVC replacement in adult recipients with hepatocellular carcinoma or Budd-Chiari syndrome, but all vessel substitutes were synthetic, because sizable IVC homograft is unavailable. In pediatric recipients, various vein homografts such as iliac vein, IVC and other large-sized veins, can be used depending on body size of recipient and availability of vessel grafts.