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Featured researches published by Katsuhiro Asonuma.


Transplantation | 1999

Impact of graft size mismatching on graft prognosis in liver transplantation from living donors

Tetsuya Kiuchi; Mureo Kasahara; Kenji Uryuhara; Yukihiro Inomata; Shinji Uemoto; Katsuhiro Asonuma; Hiroto Egawa; Shiro Fujita; Michihiro Hayashi; Koichi Tanaka

BACKGROUND Although living donor liver transplantation for small pediatric patients is increasingly accepted, its expansion to older/larger patients is still in question because of the lack of sufficient information on the impact of graft size mismatching. METHODS A total of 276 cases of living donor liver transplantation, excluding ABO-incompatible, auxiliary, or secondary transplants, were reviewed from graft size matching. Forty-three cases were highly urgent cases receiving intensive care preoperatively. Cases were categorized into five groups by graft-to-recipient weight ratio (GRWR): extra-small-for-size (XS; GRWR<0.8%, 17 elective and 4 urgent cases), small (S; 0.8< or =GRWR< 1.0%, 21 and 7), medium (M; 1.0< or =GRWR<3.0%, 119 and 19), large (L; 3.0< or =GRWR<5.0%, 67 and 10), and extra-large (XL; GRWR> or =5.0%, 9 and 3). RESULTS Smaller-for-size grafts were associated not only with larger and older recipients, but also with rather older donors. Posttransplant bilirubin clearance was delayed and aspartate aminotransferase corrected by relative graft size was higher in XS and S. Posttransplant hemorrhage and intestinal perforation were more frequent in XS and S, and vascular complications and acute rejection were more frequent in larger-for-size grafts. Consequently, graft survival in XS (cumulative 58% and actuarial 42% at 1 year) and S (76% and 74%) was significantly lower compared with that in M (93% and 92%) in elective cases. Graft survival in L (83% and 82%) and XL (75% and 71%) did not reach statistical significance. CONCLUSIONS The use of small-for-size grafts (less than 1% of recipient body weight) leads to lower graft survival, probably through enhanced parenchymal cell injury and reduced metabolic and synthetic capacity. Although large-for-size grafts are associated with some anatomical and immunological disadvantages, the negative impact is less pronounced.


Transplantation | 1999

Right lobe graft in living donor liver transplantation.

Yukihiro Inomata; Shinji Uemoto; Katsuhiro Asonuma; Hiroto Egawa; Tetsuya Kiuchi; Shiro Fujita; Michihiro Hayashi; Mayumi Kawashima; Koichi Tanaka

BACKGROUND For the sake of donor safety in living donor liver transplantation (LDLT), the left lobe is currently being used most often for the graft. However, size mismatch has been a major obstacle for an expansion of the indication for LDLT to larger-size recipients, because a left lobe graft is not safe enough for them. METHODS In 1998, LDLT using a right lobe graft was introduced and performed on 26 recipients to overcome the small-for-size problem. The right lobe, which does not include the middle hepatic vein of the donor, was used. Initially, indication for right lobe LDLT was basically defined as an estimated left lobe graft volume/recipient body weight ratio (GRWR) of <0.8%, which was later raised to <1.0%. RESULTS All the donors recovered from the operation without persistent complications. Two donors with transient bile leakage were successfully treated with a conservative approach. A right lobectomy resulted in more blood loss (337+/-175 ml), and a longer operative time (6.67+/-0.85 hr) than a lateral segmentectomy, but not a left lobectomy. Grafts with a GRWR >0.8% were implanted in all recipients, except for two, who received relatively smaller right lobes (GRWR of 0.68% and 0.66%). In one of these two, the right lobe from the donor was used as the orthotopic auxiliary graft. Postoperative transitory increases in total bilirubin and aspartate transaminoferase for right lobe donors were higher than those for the left lateral segmentectomy. Nineteen recipients (73.1%) were successfully treated with this procedure. The causes of death were not specific for right lobe LDLT, except for one patient with a graft that had multiple hepatic venous orifices. These multiple and separate anastomoses of the hepatic veins caused an outflow block as a result of a positional shift of the graft, which finally led to graft loss. CONCLUSION Our experience suggests that right lobe grafting is a safe and effective procedure, resulting in the expansion of the indication for LDLT to large-size recipients. How to deal with the possible variation in the anatomy of the right lobe graft should be given attention throughout the procedure.


Transplantation | 1998

Transmission of hepatitis B virus from hepatitis B core antibody- positive donors in living related liver transplants

Shinji Uemoto; Kohachiro Sugiyama; Hiroyuki Marusawa; Yukihiro Inomata; Katsuhiro Asonuma; Hiroto Egawa; Tetsuya Kiuchi; Yoshishige Miyake; Koichi Tanaka; Tsutomu Chiba

BACKGROUND In order to clarify the risk of hepatitis B virus (HBV) transmission from hepatitis B core antibody-positive (HBcAb(+)) donors and to evolve a new strategy to counter such a risk, we undertook a retrospective (1990-1995) and prospective (1995-1996) analysis of our experience with living related liver transplantation involving HBcAb(+) donors. METHODS Between June 15, 1990, and June 30, 1995, HBcAb(+) individuals were not excluded as donor candidates at our institutions. For 171 liver transplants, 16 donors were HBcAb(+). Between July 1, 1995, and June 30, 1996, HBcAb(+) individuals were generally excluded as donor candidates; however, three recipients were given liver grafts from HBcAb(+) donors because other donor candidates presented even higher risks. In the latter period, recipients with transplants from HBcAb(+) donors underwent prophylactic passive immunization with hyperimmune hepatitis B immunoglobulin (HBIG). The serum of 10 HBcAb(+) donors was examined by nested polymerase chain reaction for the presence of HBV-DNA, but it was not detected in any of them. However, the same examination of the liver tissue of five such donors yielded positive results in all cases. RESULTS In the first 5-year period, out of 16 recipients with HBcAb(+) donors, 15 became hepatitis B surface antigen-positive after transplant. The three recipients with HBcAb(+) donors during the second 1-year period, who were treated by prophylactic passive immunization with HBIG, remained hepatitis B surface antigen-negative and negative for serum HBV-DNA after transplant. CONCLUSIONS HBV exists in the liver of healthy HBcAb(+) individuals, but not in the blood. Therefore, HBV is thought to be transmitted to recipients by liver grafts from the HBcAb(+) donors at a significantly high rate. The prevention of viral activation and clinical disease development by means of passive immunization with HBIG seems promising, although the follow-up period in our study may be too short for any definitive conclusions.


World Journal of Surgery | 2001

Biliary Anastomotic Complications in 400 Living Related Liver Transplantations

Hiroto Egawa; Yukihiro Inomata; Shinji Uemoto; Katsuhiro Asonuma; Tetsuya Kiuchi; Shiro Fujita; Michihiro Hayashi; Maria A. Matamoros; Kyo Itou; Koichi Tanaka

Abstract. The purpose of this study was to evaluate the cause and outcome of biliary anastomotic complications occurring after living related liver transplantation (LRLT). A database of 391 patients undergoing 400 LRLT from June 1990 to August 1998 was reviewed. The overall incidence of biliary anastomotic complications was 18.2% (71 patients). There were 45 bile leaks, 35 anastomotic strictures, and the bile duct was ligated inadvertently in 3 cases. Univariative analysis revealed that the manner of stent usage, intrapulmonary shunting, and gender of recipients were significant risk factors for leakage. Anastomotic leaks, cytomegalovirus infection, hepatic artery complications, and gender of recipients were significant risk factors for stricture. In pediatric patients older than 2 years old, ABO blood type compatibility was another risk factor for leakage and stricture. Choice of stent usage and earlier transplantation for patients with intrapulmonary shunting should reduce the rate of biliary leaks, and prophylaxis of leaks for patients with intrapulmonary shunting, and minimizing hepatic artery complications should reduce the rate of biliary stricture after LRLT. Avoidance of ABO-incompatible donors or innovative immunosuppression in ABO-incompatible transplantation should be considered in children.


Surgery | 1997

Hepatic vein reconstruction in 152 living-related donor liver transplantation patients

Hiroto Egawa; Yukihiro Inomata; Shinji Uemoto; Katsuhiro Asonuma; Tetsuya Kiuchi; Hideaki Okajima; Yoshio Yamaoka; Koichi Tanaka

BACKGROUND Hepatic vein (HV) reconstruction is crucial in partial liver transplantation in which the inferior vena cava (IVC) is preserved. METHODS We reviewed the medical records of 152 living-related donor liver transplantations (LRDLTs) in 150 children (45 left lobe grafts, 106 lateral segment grafts, and 1 right lobe graft) monitored for 12 months or longer. RESULTS A standard technique was a wide end-to-side anastomosis between the donor HV and cuffs, consisting of the recipient middle and left HV and an incision to the IVC. In 15 of 22 partial grafts with two separated HVs the two vessels were reformed by back table surgery to have a common anastomotic orifice, and two separate anastomoses of the individual vessels were made for the remaining seven grafts. Four patients with an absence of infrahepatic IVCs and two with completely obstructed IVCs had end-to-end anastomoses with recipient IVCs. Four patients with stenotic IVCs had end-to-side anastomoses with new orifices on the IVCs. Two patients had acute HV obstruction caused by twisting of the HV that required laparotomy, and six had late-onset HV obstruction that required radiologic intervention. A tissue expander was placed prophylactically in the right subphrenic space in 10 patients to prevent the dislocation of the graft into the right subphrenic space. CONCLUSIONS It is important in HV reconstruction in partial liver transplantation to make wide orifices and to adapt each graft to its orthotopic place, taking into consideration graft shape, size of the abdominal cavity of the recipient, and anatomic variations in vessels.


Surgery | 1998

Biliary complications in pediatric living related liver transplantation

Hiroto Egawa; Shinji Uemoto; Yukihiro Inomata; A.M.James Shapiro; Katsuhiro Asonuma; Tetsuya Kiuchi; Hideaki Okajima; Kyo Itou; Koichi Tanaka

BACKGROUND The goal of this study was to evaluate cause and outcome of biliary complications occurring after pediatric living related liver transplantation (LRLT). METHODS A database of 205 pediatric patients (71 male and 134 female) undergoing 208 LRLT from June 1990 to April 1996 was reviewed. RESULTS The overall incidence of bile duct complications was 13.9% (29 patients). There were 19 bile leaks, 7 anastomotic strictures, 8 intrahepatic biliary complications, and the bile duct was ligated inadvertently in 2 cases. Logistic regression analysis revealed hepatic artery thrombosis, ABO incompatible transplantation, intrapulmonary shunting in recipients, mode of artery reconstruction, and cytomegalovirus infection were all significant risk factors for biliary complications. CONCLUSIONS Avoidance of ABO incompatible transplantation where possible, routine use of microvascular techniques for hepatic artery reconstruction to minimize the risk of artery thrombosis, earlier transplantation for patients with intrapulmonary shunt, and prophylaxis against cytomegalovirus infection should all reduce the rate of biliary complications after LRLT in pediatric recipients.


Transplantation | 1997

Hepatic artery thrombosis in living related liver transplantation

Etsuro Hatano; Hiroaki Terajima; Shin Ichi Yabe; Katsuhiro Asonuma; Hiroto Egawa; Tetsuya Kiuchi; Shinji Uemoto; Yukihiro Inomata; Koichi Tanaka; Yoshio Yamaoka

BACKGROUND Hepatic artery thrombosis (HAT) after orthotopic liver transplantation remains a significant cause of graft loss in pediatric patients. We previously reported that the microsurgical techniques for arterial anastomosis can reduce the incidence of HAT in living related liver transplantation (LRLT). The purpose of this study is to analyze the risk factors for HAT after LRLT. A total of 245 patients received 250 liver transplants. METHODS Eight arteries in eight patients, reconstructed with the use of loupe magnification (HAT; 1/8, 12.5%), were excluded from this study. We observed HAT in 4 patients of the 242 transplants (1.7%, HAT group). Seventeen factors were compared between the HAT and the control group (those without HAT). RESULTS HAT occurred in 3 of 33 grafts (9%) from ABO-incompatible donors, whereas it occurred in 1 of 209 grafts (0.5%) from identical or compatible donors (P=0.008). The corrected volume of fresh-frozen plasma intraoperatively transfused in the HAT group (46.9+/-30.3 ml/kg) was significantly (P=0.015) different from that in the control group (10.2+/-1.9 ml/mg). In all four patients with HAT, emergent revisions of the anastomosis were performed. Two patients with ABO-incompatible grafts died of hepatic failure and sepsis. CONCLUSIONS Although microsurgical techniques can minimize the surgical risk factors for HAT, overtransfusion of fresh-frozen plasma in high-risk patients (ABO incompatible) may be a critical factor in the development of HAT in LRLT.


Transplantation | 1999

Auxiliary partial orthotopic living donor liver transplantation as an aid for small-for-size grafts in larger recipients.

Yukihiro Inomata; Tetsuya Kiuchi; Il Deok Kim; Shinji Uemoto; Hiroto Egawa; Katsuhiro Asonuma; Shiro Fujita; Michihiro Hayashi; Koichi Tanaka

BACKGROUND In countries where living donors are the only source of liver grafts, restrictions on graft size are a serious obstacle for the expansion of indications for adult recipients. To overcome this problem, auxiliary partial orthotopic liver transplants (APOLT*) was performed on the basis of the concept that the residual native liver would support the graft function until the graft had grown enough to function by itself. METHODS APOLT as an aid for small-for-size (SFS) grafts was reviewed retrospectively to evaluate its feasibility. Between April 1995 and March 1998, 20 recipients underwent APOLT, which was indicated because of a SFS graft in 15 of them. The indication was based on the estimated graft/recipients body weight ratio (GRWR). If the ratio was <0.8%, APOLT was performed. The other 5 patients had a graft with a GRWR >0.8% and underwent APOLT on the basis of the residual native liver supporting the graft function temporarily, 4 for supplementation of the defective enzyme in metabolic liver diseases and one for leaving the potential of the regeneration of the native liver in fulminant hepatic failure. The recipients who underwent APOLT because of a SFS graft were categorized as the SFS group, and the others were the second group. RESULTS In the SFS group, the age of the recipients ranged from 13 to 48 (median 23). The original indications of this group were fulminant hepatic failure in 2 recipients, acute deterioration of chronic liver diseases in 3, Wilsons disease in 2, biliary atresia in 4, primary biliary cirrhosis in 3, and primary sclerosing cholangitis (PSC) in one. The actual GRWR ranged from 0.45 to 0.72 (median 0.55). The graft was implanted after resection of the left lateral segment of the native liver. Except in the first two patients, the portal vein to the residual native liver was completely transected so that all of the portal blood drained into the graft liver. This procedure was successful in 9 patients. The cause of death in the other 6 was mainly infection. The mortality rate among the recipients with signs of advanced liver failure, such as massive ascites or hepatic coma, was higher, even though APOLT was used to support the SFS graft. In the second group, in the other five recipients who underwent APOLT for other indications, one recipient with fulminant hepatic failure died of sepsis caused by the dehiscence of bilio-enteric anastomosis. CONCLUSIONS APOLT as an aid for a SFS graft is technically viable. This procedure can thus expand the indication of living donor liver transplants for adult recipients when the native liver retains some functional capability to support the grafted liver during the immediate postoperative period.


Neurology | 2012

Long-term survival after liver transplantation in patients with familial amyloid polyneuropathy

Taro Yamashita; Yukio Ando; Sadahisa Okamoto; Y. Misumi; Tomoo Hirahara; M. Ueda; K. Obayashi; Masanobu Nakamura; Hirofumi Jono; Makoto Shono; Katsuhiro Asonuma; Yukihiro Inomata; Makoto Uchino

Objective: Familial amyloid polyneuropathy (FAP), which is a fatal disorder inherited in an autosomal dominant fashion, is characterized by systemic accumulation of polymerized transthyretin (TTR) in the peripheral nerves and systemic organs. Liver transplantation has become an accepted treatment of this disorder because it stops the major production of amyloidogenic TTR. However, improved survival of transplant patients compared with that of nontransplant patients has not been sufficiently demonstrated. This study investigated whether transplantation improved the long-term outcome of patients by comparing the survival of patients who had transplantations with that of patients who had not had transplantations. Methods: Eighty consecutive patients with FAP Val30Met who visited Kumamoto University Hospital between January 1990 and December 2010 were studied. The transplant group consisted of 37 patients who had a partial hepatic graft via living donor transplantation in Japan or who underwent liver transplantation in Sweden, Australia, or the United States. The nontransplant group consisted of 43 patients with FAP. Survival was evaluated by using Kaplan-Meier analysis, and the difference in survival was examined via the log-rank test. Results: The transplant group had prolonged survival (p < 0.001) compared with the nontransplant group. The estimated probability of survival at 10 years was 56.1% for the nontransplant group vs 100% for the transplant group. Conclusion: Liver transplantation should be considered as an effective treatment in clinical management of patients with FAP Val30Met. Classification of evidence: This study provides Class III evidence that liver transplantation prolongs survival in patients with FAP Val30Met.


Liver Transplantation | 2005

Magnet compression anastomosis for bile duct stenosis after duct‐to‐duct biliary reconstruction in living donor liver transplantation

Hideaki Okajima; Atsushi Kotera; Takayuki Takeichi; Mikako Ueno; Taketoshi Ishiko; Masahiko Hirota; Katsuhiro Asonuma; Eijiro Yamauchi; Yukihiro Inomata

A 44-year-old woman who had undergone living donor liver transplantation for fulminant hepatic failure presented obstructive jaundice 1 year after transplantation. A right lobe from her husband had been used for the original graft. Intraoperative cholangiography of the donor showed the bile duct of posterior inferior segment (B6) branching from the bile duct of anterior segment (Fig. 1). The bile duct of the donor was transected in the very short segment of the common trunk of the posterior and anterior branches of the right lobe. The orifice of the bile duct of the graft was single, but the shape of it was like the nose of a pig. This single orifice was anastomosed to the stump of the recipient’s common hepatic duct. A biliary stent tube (4-Frenchsized) was inserted into only the bile duct of the posterior segment. Coldand warm-ischemia time was 42 and 45 minutes, respectively. She initially recovered uneventfully in the early period after liver transplantation. The external stent tube was removed 3 months after the transplantation. Laboratory data at 11 months after the transplantation showed slight elevation of transaminases (aspartate aminotransferase: 80 IU/L, alanine aminotransferase: 100 IU/L) and total bilirubin (1.4 mg/dL). One month later, ultrasonography showed the dilated intrahepatic duct. Endoscopic retrograde cholangiography and percutaneous transhepatic cholangiography disclosed the complete obstruction of the anterior branch (Fig. 2). The dilated duct was drained by the percutaneous transhepatic cholangiography drainage tube. Balloon dilatation was attempted though the percutaneous transhepatic cholangiography drainage tube, but it was

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