Koichi Suto

Yamagata University, Ямагата, Yamagata, Japan

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Publications (17)18.31 Total impact

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    ABSTRACT: Adult-onset type II citrullinemia (CTLN2) is a rare disorder of the urea cycle resulting in hyperammonemia, with a poor prognosis. Here we report a 48-year-old Japanese man who showed abnormal nocturnal behavior. Laboratory data indicated raised plasma concentrations of ammonia and citrulline, and a definitive diagnosis of CTLN2 was made by DNA analysis. Hyperammonemia was not improved by oral intake of branched-chain amino acids (BCAA), whereas venous infusion of BCAA was effective. Western blotting revealed heterozygotic expression of citrin protein in a liver biopsy specimen from the patient's brother. However, as symptomatic CTLN2 is very unusual in a heterozygotic carrier, we considered the brother suitable as a living-donor liver transplantation (LDLT) donor. The recipient's entire liver was removed, and replaced with the left liver graft. The plasma ammonia level remained low without infusion of BCAA after liver transplantation. From this case we conclude that venous infusion, rather than oral administration, of BCAA is useful for conservative treatment of CTLN2. However, liver transplantation is the only effective therapeutic option for CTLN2, and should be performed before irreversible encephalopathy occurs. Use of a graft from heterozygotic donors is permissible treatment for CTLN2.
    Hepato-gastroenterology 11/2008; 55(88):2211-6. · 0.93 Impact Factor
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    ABSTRACT: This study investigated the results of hepatectomy for multiple liver metastases and repeated hepatectomy for recurrent hepatic metastases. A proposed treatment strategy for liver metastases is discussed. Fifty-seven consecutive cases of liver metastases were studied. The metastases originated from colon cancer (24 cases), rectal cancer (11 cases), gastric cancer (14 cases), or gastrointestinal stromal tumors (two cases). The other cases included one each of gastric carcinoid, carcinoma of the papilla of Vater, cystic duct cancer, esophageal cancer, choriocarcinoma and breast cancer. The overall 5-year survival rate for the 57 cases was 45.4%; there was no significant difference between patients with colon cancer (56.3%), rectal cancer (45.5%), or gastric cancer (41.6%). The cumulative 5-year survival rates for synchronous and metachronous metastases were 38.3% and 50.8%, respectively (difference not statistically significant; NS). The survival rates for single and multiple metastases were 56.0% and 31.3% (NS), and those for monolobar and bilobar metastases were 48.5% and 40.9% (NS), respectively. Concerning the operative procedure, the survival rates for partial resection and hemi-hepatectomy were 49.5% and 26.9%, respectively (NS). The survival rates for surgical margins <4mm and >5mm were 45.9% and 45.4%, respectively (NS), and those for single and repeat hepatectomy were 40.5% and 58.2% (NS). Preoperative portal embolization was performed in seven cases because of multiple metastases or a tumor located in a deeper site in the liver. There was no hospital death among the 57 cases. These results show that hepatectomy may offer longer survival, even in patients with multiple or bilobar metastases. Neither the operative procedure nor the size of the surgical margin had any influence on survival after hepatectomy. The prognosis was improved not only for metastases from colorectal cancer, but also for gastric cancer. An increased survival benefit was obtained by repeat hepatectomy for recurrent hepatic metastases. Preoperative portal embolization extended the indication for hepatectomy and provided postoperative safety.
    Hepato-gastroenterology 09/2006; 53(71):757-63. · 0.93 Impact Factor
  • Wataru Kimura · Akira Fuse · Ichirou Hirai · Koichi Suto ·
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    ABSTRACT: Recently, the significance of preserving the spleen has received a lot of attention. Since our first trial and success of spleen-preserving distal pancreatectomy with conservation of the splenic artery and vein for chronic pancreatitis, this procedure has been more frequently performed and reported. In this study, we introduce the technique and indications for the procedure for intraductal papillary mucinous tumor of the pancreas. Nine patients underwent spleen-preserving distal pancreatectomy with conservation of the splenic artery and vein. We performed this procedure in two patients with intraductal papillary mucinous tumor. The splenic vein is identified behind the pancreas and within the thin connective tissue membrane. The connective tissue membrane is cut longitudinally above the splenic vein. An important technique is to remove the splenic vein from the pancreas from the body of the pancreas toward the spleen. There are many branches from the splenic vein on both sides, and these branches should be carefully ligated and cut. The pancreas is removed from the splenic artery from the spleen toward the head of the pancreas. This procedure is much easier than removing the pancreas from the vein. The postoperative course was uneventful in all nine cases, but one, in which pancreatic fistula continued for more than several weeks. The mean and standard deviation of the operative blood loss, the duration of the operation and the postoperative hospital stay in seven cases, excluding two cases, in which either Puestow's procedure or simultaneous subtotal esophagectomy was performed, were 413+/-385 mL, 298+/-55 min, and 39+/-15 days, respectively. Severe complications were not found in any of the nine cases. The two patients with intraductal papillary mucinous tumor have been followed as outpatients without any recurrence. Spleen-preserving distal pancreatectomy with conservation of the splenic artery and vein is easy and safe, and should be performed for some of the patients with intraductal papillary mucinous tumor of the pancreas.
    Hepato-gastroenterology 01/2004; 51(55):86-90. · 0.93 Impact Factor
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    ABSTRACT: Preservation of the spleen at distal pancreatectomy has recently attracted considerable attention. Since our first trial and success with spleen-preserving distal pancreatectomy with conservation of the splenic artery and vein for tumors of the pancreas and chronic pancreatitis, this procedure has been performed more frequently. Three patients with intraductal papillary-mucinous tumor underwent spleen-preserving distal pancreatectomy with conservation of the splenic artery and vein. In this procedure, the splenic vein is identified behind the pancreas and the connective tissue membrane is cut longitudinally above the splenic vein. An important point is to remove the splenic vein from the pancreas from the body of the pancreas toward the spleen. In one patient with intraductal papillary-mucinous tumor in the body of the pancreas who had undergone distal gastrectomy for duodenal ulcer 32 years previously, residual proximal gastrectomy could be avoided with this procedure. In this case, the histological diagnosis was a pseudocyst, and epithelial dysplasia was found in other pancreatic ductuli. In another case, epithelia were borderline between hyperplasia and adenoma. In both of these cases, the histological diagnosis was different from the preoperative diagnosis. Even with advances in imaging techniques, diagnosis of a cystic lesion of the pancreas is still very difficult. Ordinary distal pancreatectomy with splenectomy would have been oversurgery in these two cases, which could be avoided using our procedure. Severe complications were not found in any of the three cases and the postoperative course was uneventful. The patients have been followed as outpatients without any recurrence. Spleen-preserving distal pancreatectomy with conservation of the splenic artery and vein is easy and safe, and should be performed for some patients with intraductal papillary mucinous tumor of the pancreas.
    Hepato-gastroenterology 11/2003; 50(54):2242-5. · 0.93 Impact Factor
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    ABSTRACT: Preoperative portal embolization (PE) is used to stimulate liver hypertrophy in the nonembolized lobe. We studied liver volume and function with computed tomography and technetium-99m-galactosyl human serum albumin ((99m)Tc-GSA) scintigraphy before PE and at 1 or 2 weeks after PE. Right PE was performed in 30 patients. Morphologic and functional hypertrophy in the left lobe after PE was determined and related to the presence or absence of cholestasis, biliary drainage of the embolized lobe, and postoperative liver failure. The volume of the left lobe and (99m)Tc-GSA uptake increased rapidly for the first week after PE, but no significant increase was seen during the second week. Morphologic hypertrophy was less pronounced in patients with jaundice (P =.03). When PE was performed at a total bilirubin level above 2 mg/dL, the interval between PE and surgery was prolonged because of cholangitis and liver abscess formation. The net morphologic hypertrophy ratio was significantly higher in livers that had undergone left lobe drainage only (9.1% +/- 0.9%) compared with those in which there was drainage of the embolized lobes (5.7% +/- 0.9%; P =.03). The volume and (99m)Tc-GSA uptake of the left lobe in the second week after PE was significantly smaller in patients with postoperative liver failure (33.7% +/- 2.4% and 18.0% +/- 2.1%, respectively) than in patients without liver failure (46.2% +/- 1.4% and 38.4% +/- 2.3%; P =.003 and P =.01, respectively). In the nonembolized lobe, the functional increase in (99m)Tc-GSA uptake is more pronounced than suggested by the degree of morphologic hypertrophy. Whenever possible, biliary drainage should not be performed in the lobe undergoing hepatectomy. (99m)Tc-GSA SPECT scintigraphy is useful for the evaluation of postoperative liver failure.
    Surgery 06/2003; 133(5):495-506. DOI:10.1067/msy.2003.138 · 3.38 Impact Factor
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    ABSTRACT: Hilar bile duct cancer progresses slowly but easily invades the nearby portal vein or hepatic artery. Thus, in some cases, curative resection is impossible, so we need to determine the best non-surgical treatments for this tumor. We classified 98 patients with hilar bile duct cancer into 3 categories: a non-surgical group (34 cases), an exploratory laparotomy group (9 cases), and a surgical resection group (55 cases). Survival rates were examined in the light of clinical factors. In the non-surgical group, extensive vessel invasion was the most common reason for unresectability (13 cases), with broad biliary extension the second most common (11 cases). In the exploratory laparotomy group the most common reason for unresectability was severe vessel invasion (6 cases). Cumulative 1- and 2-year survival rates for patients with unresectable tumors without distant metastasis were 26.9% and 7.2%, respectively. One- and 2-year survival rates for patients with unresectable tumors and with total bilirubin of less than 2 mg/dL on discharge were 36.8% and 9.8%, respectively. The 1-year survival rate with placement of an expandable metallic stent was as high as 55.6%; without the stent it was 7.1% (P = 0.005). Radiation therapy gave a better prognosis than did no radiation (P = 0.01). Portal and arterial invasion were the principal reasons for unresectability. Use of an expandable metallic stent or radiation therapy, and a total bilirubin level of less than 2 mg/dL on discharge, were factors that enhanced survival in unresectable cases, but distant metastasis, dissemination, and poor general condition or liver function were negative factors for survival.
    Hepato-gastroenterology 05/2003; 50(51):614-20. · 0.93 Impact Factor
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    ABSTRACT: Although the progression of hilar bile duct cancer is slow, without adequate treatment the prognosis becomes poor. Margin-positive or negative resection has often been reported to correlate with the prognosis. Moreover, the value of combined vessel resection for hilar bile duct cancer is still obscure. Fifty-five out of 98 cases of hilar bile duct cancer were treated with surgery. The patients were classified as a microscopic margin-positive resection group with 12 cases and a microscopic margin-negative resection group with 43 cases. The agreement between preoperative diagnosis and pathological findings of resected specimens was examined, as were cumulative survival rates according to clinical and pathological factors. In diagnosis of portal invasion with computed tomography, the rate of coincidence, overestimate and underestimate were 69.8%, 13.2% and 17.0%, respectively. Corresponding rates in diagnosing arterial invasion were 58.5%, 15.1% and 26.4%, respectively, and for lymph node metastasis 54.7%, 9.4% and 35.8%, respectively. The 5-year survival rates for margin-positive and negative resection groups were 17.9% and 26.5%, respectively (NS). Patients surviving for more than 1 year in the margin-positive resection group tended to exhibit exposed cancer cells only at the bile duct, rarely showing lymph node metastases. Combined arterial resection had a poor prognosis and high, usually lethal, complication rates. Accurate preoperative diagnosis rates of vessel invasion and lymph node metastasis were 60-70% and 56%, respectively. The long-term survival was expected even in margin-positive resection cases without lymph node metastasis. Combined hepatic arterial resection showed no clinical advantage.
    Hepato-gastroenterology 05/2003; 50(51):629-35. · 0.93 Impact Factor
  • Ichiro Hirai · Wataru Kimura · Gen Murakami · Koichi Suto · Akira Fuse ·
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    ABSTRACT: The inferior vena cava ligament is a fibrous membrane located around the inferior vena cava. Few reports exist on the ligament's location, attachment to the liver, or the inferior vena cava. We obtained 16 specimens of human liver and inferior vena cava from cadavers. The inferior vena cava ligament was photographed and then dissected for histological examination. Relationships among the ligament, inferior vena cava, and liver were examined microscopically. The numbers and diameters of veins, arteries, and lymph vessels at least 1 mm in diameter were recorded. The cranial margin of the inferior vena cava ligament was ended in a blind loop. The cranial portion above the mid-portion of the Spiegel lobe was thicker than the caudal portion. The ligament was attached to the right and left hepatic veins. The mean length of the right side of the inferior vena cava ligament was 37.0 mm and the mean width 15.6 mm. The inferior vena cava ligament had a mean thickness of 0.8 mm (thin end) and 2.5 mm (thick end). Although the inferior vena cava ligament was usually tightly continuous with the liver capsule, microscopically the attachment between the ligament and the inferior vena cava was loose. The mean number and diameter of veins in the inferior vena cava ligament was 1.0 and 1.4 mm, respectively. The mean number and diameter of arteries was 0.2 and 2.4 mm, respectively. The mean number and diameter of lymphatic vessels was 2.8 and 1.7 mm, respectively. After dissection of the inferior vena cava ligament, major hepatic veins can be dissected extrahepatically. Because the ligament is wider caudally, the forceps should be inserted caudocranially during separation. Since both the number and diameters of lymphatic vessels in the ligament are large, the ligament should be ligated and cut.
    Hepato-gastroenterology 01/2003; 50(52):983-7. · 0.93 Impact Factor
  • Koichi Suto · Akira Fuse · Yukio Igarashi · Wataru Kimura ·
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    ABSTRACT: Hyperbilirubinemia occurs as a sign of hepatic failure after hepatectomy. The pathogenesis of this event has not been elucidated. In cases complicated with postoperative infection, hyperbilirubinemia is prolonged and the composition of bilirubin subfractions in bile changes markedly. A reduction in the proportion of bilirubin diglucuronide (BDG) is especially notable. This study was aimed at clarifying the relationship between infection and biliary bilirubin subfractions, with a view to shedding light on the mechanisms of change. Rats underwent either laparotomy or partial hepatectomy (Hx). Daily intraperitoneal injections of lipopolysaccharide (LPS) or natural saline were administered for 3 days following surgery. Total serum bilirubin levels and proportions of BDG and bilirubin in bile were measured until Day 5 after the operation. Hepatic levels of UDP-glucuronic acid (UDP-GA), UDP-glucose, NAD(+), and total adenine nucleotides (TAN) and activities of UDP-glucuronyltransferase (UDP-GT) and UDP-glucose dehydrogenase were measured on Day 4. In hepatectomized rats treated with LPS (Hx-LPS), total serum bilirubin levels were elevated, biliary bilirubin levels were decreased, and the proportion of biliary BDG was decreased on Day 4. Hepatic levels of UDP-GA, NAD(+), and TAN and activities of UDP-GT in Hx-LPS were reduced. In all groups tested, a significant linear correlation between BDG and UDP-GA and between UDP-GA and NAD(+) was found. The reduction of UDP-GA might be effected by reduced hepatic levels of NAD(+) in endotoxemia following hepatectomy. It is therefore suggested that alterations in biliary bilirubin subfractions might accurately reflect the energy state of the remnant liver following hepatectomy.
    Journal of Surgical Research 08/2002; 106(1):62-9. DOI:10.1006/jsre.2002.6437 · 1.94 Impact Factor
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    ABSTRACT: Perineural invasion is regarded as a factor associated with local recurrence of pancreatic cancer. To examine perineural invasion of pancreatic cancer pathologically and clinically. In 24 cases of surgically resected pancreatic cancer, correlations among the degree of perineural invasion, differentiation, interstitial connective tissue, lymph node metastasis, and survival rate were examined. Consecutive 5-microm serial sections (n = 1072) were made in six cases that showed characteristic mode of perineural invasion. Perineural invasion was observed in 17 cases (70.8%; ne0-7; ne1-6; ne2-9; and ne3-2 cases). Perineural invasion was absent in three of five cases of papillary carcinoma, but was observed in 12 of 14 cases of moderately differentiated carcinoma. The survival rate for ne0 was better than that of the other groups, with the 3-year survival rate being 57.1%. Perineural cancer glands had developed discontinuously in two cases. Perineural invasion is an important prognostic factor in pancreatic cancer, increasing as the cancer becomes undifferentiated. Even if there are no cancer cells at the margin of the pancreas at the time of surgery, the cancer cells may spread further to the noncancerous pancreas or retroperitoneum. Sufficient dissection of the neural plexus or intraoperative radiation may be required.
    Pancreas 02/2002; 24(1):15-25. DOI:10.1097/00006676-200201000-00003 · 2.96 Impact Factor
  • Koichi Suto · Wataru Kimura ·

    Nippon rinsho. Japanese journal of clinical medicine 02/2002; 60 Suppl 1:284-8.
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    ABSTRACT: Preoperative portal embolization (PE) is useful for the prevention of postoperative liver failure after extended hepatectomy. However, clinical evaluation of liver function in the hypertrophying lobe after PE has not been studied. Here we report functional changes in the hypertrophying lobe using a 80% portal-branch-ligation rabbit model. Liver function was evaluated by the expression of liver-specific genes detected by Northern blot analysis and plasma disappearance rate of indocyanine green (ICG). The weight of the unligated lobe after portal ligation increased about twofold on the 7th postoperative day (POD) and about threefold on the 14th POD. The mRNA levels of the liver-specific genes (albumin, aldolase B, and tyrosine aminotransferase) in the unligated lobe decreased to about 50% on the 1st POD and returned to the preoperative levels on the 7-14th POD. In contrast, the expression of histone H2B mRNA increased on the 3rd-7th POD. The plasma disappearance rate of ICG (K-ICG) in the rabbit that has only the unligated lobe did not significantly change during the first 7 days, but then improved and recovered to 80% of that in the rabbit that has whole liver on the 14th POD. These results indicate that liver function of the hypertrophying lobe after portal branch ligation does not increase during the first 7 days despite an increase in liver weight. This finding suggests that the compensatory hypertrophying liver is enlarging without functional augmentation in the early period after PE.
    Journal of Surgical Research 10/1999; 86(1):55-61. DOI:10.1006/jsre.1999.5687 · 1.94 Impact Factor
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    ABSTRACT: Results of surgical treatments for 57 patients who underwent resection for hepatic hilar bile duct cancer between 1984 and 1997 were studied. Bile duct resection was performed in eight patients, and combined resection of bile duct and liver was performed in 49 patients, of whom vascular reconstruction was added in 15 patients and pancreatoduodenectomy (PD) in six patients. All the operations of bile duct resection that were not combined with hepatectomy were non-curative. In the patients who underwent combined resection of the bile duct with liver, outcomes of the patients with well-differentiated adenocarcinoma were better than those with other lower-grade tumors. The factors related to the degree of tumor extension, such as serosal invasion, lymph node metastasis, lymphatic vessel invasion, perineural invasion, venous vessel invasion, and vascular involvement, were other factors which significantly influenced the survival. Curative resection yielded significantly better results than non-curative resection. Of all these variables, good tumor differentiation and vascular involvement were recognized as important prognostic factors by multivariate analysis. Most of the postoperative deaths were encountered in patients who underwent additional operations to hepatectomy, such as vascular reconstruction or PD. Improvement of surgical techniques and perioperative care has yielded better outcomes of vascular reconstruction. However, the application of hepatopancreatoduodenectomy should be limited due to poor outcomes of widespread bile duct cancer of which the histological grade is usually low. Whereas prognosis of bile duct cancer involving the hepatic hilus is mainly determined by the biologic characteristics of the tumor, surgeons should consider the fact that most patients die of local recurrence regardless of the biologic character of the tumor when curative resection is not performed.
    Journal of Hepato-Biliary-Pancreatic Surgery 02/1998; 5(4):429-36. DOI:10.1007/s005340050068 · 1.60 Impact Factor

  • Nihon Rinsho Geka Gakkai Zasshi (Journal of Japan Surgical Association) 01/1998; 59(11):2891-2894. DOI:10.3919/jjsa.59.2891

  • 01/1991; 52(12):2971-2976. DOI:10.3919/ringe1963.52.2971
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    ABSTRACT: 【背景】末期肝疾患に対する肝移植は、多くの肝疾患の根治的な治療として定着し、安定した長期成績をあげている。当科ではブタでの生体肝移植術を行ない、ヒトでの生体肝移植のシミュレーションを行なっており、その手術手技の要点と工夫について報告する。 【方法】1回の移植で15kg前後の畜産用ブタを2匹使用した。1頭はドナーとし、輸血用血液を採取した。もう1頭はレシピエントとした。麻酔は全身吸入麻酔を用いた。 【手術術式】ドナー手術 逆T字切開で開腹した。肝十二指腸間膜を切開し、総胆管、総肝動脈、左・中・右肝動脈、門脈本幹にテーピングした。肝鎌状間膜を切離し、肝静脈の下大静脈(IVC)流入部を露出した。総胆管切離後、門脈本幹はできるだけ長く距離を取った。肝動脈を切離し、肝下部下大静脈(IHVC)は腎静脈流入部直上で切離した。ブタでは横隔膜下の肝上部下大静脈(SHVC)が極めて短いため、大腿動脈から輸血用に脱血後、横隔膜ごと右心房近くからグラフトを摘出することがコツである。 バックテーブル手術 全肝グラフトを氷中で処置した。門脈よりヘパリン加冷ラクテートリンゲルで還流し、肝実質やIVCの小損傷を修復した。 レシピエント手術 正常肝のブタでは、門脈を遮断すると急激に全身状態が悪化する。よってヘパリン化親水性カテーテルを用い、脾静脈から上腸間膜静脈に挿入し、門脈血を左外頸静脈にバイパスし腸管のうっ血を防いだ。さらにIVC を切離するため、ヘパリン化親水性カテーテルをIVCに挿入し、右外頸静脈にバイパスした。この2 本のシャントが工夫した点である。 SHVC、IHVC吻合、門脈吻合を行なった。肝動脈吻合は顕微鏡下で施行した。胆道再建は胆管胆管端々吻合で行ない、細いステントチューブを留置している。 【結果】2本のアンスロンチューブによる門脈、IVC血のバイパスで、循環動態に大きな変動はなく、安全に生体肝移植術が施行できた。 【結論】本術式の特徴は、ドナー手術では、右心房からIVCを採取することで長いSHVCが得られ、グラフトとの吻合が容易である。レシピエントの無肝期に2本のヘパリン化親水性カテーテルで門脈、下大静脈血のバイパスを行なう。本モデルは実際のヒト生体肝移植術と同じ口径で肝静脈(IVC)、門脈、肝動脈、胆管の吻合を行なうことができ、実践に近いモデルと考えられた。 キーワード : 肝移植、ブタ、ヘパリン化カテーテル  Liver transplantation is curative treatment for various liver diseases in terminal stage. We report the surgical technique of the liver transplantation in pig model. Body weight of pigs used in this study was about 15 kg.Operation was performed under general anesthesia. Donor operation:After laparotomy,common bile duct,hepatic artery,and portal vein were taped and divided.The infra-hepatic vena cava was divided above the renal vein. Because the supra-hepatic vena cava (SHVC)of the pig is very short,the SHVC was divided near the right atrium. Back table operation:Graft was perfused via portal vein with cold saline added heparin sodium on crushed ice. Recipient operation:In the pig model,when portal flow is intercepted,general condition,such as blood pressure,becomes worse.Therefore,we used heparinized catheters to maintain both portal and vena cava blood flow.The anastomosis of the supra-and infra-hepatic vena cava,portal vein,hepatic artery,and bile duct were established. In conclusion,anastomosis of the SHVC became an easy procedure when long SHVC was dissected near the right atrium.Portal and vena cava bypass with heparinized catheters is a convenient option for safe liver transplantation. Key words : liver transplantation, pig, heparinized catheter
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    ABSTRACT:  A 74-year-old man presented with epigastralgia and was diagnosed as having cholelithiasis. Endoscopic retrograde cholangiopancreatography (ERCP) initially visualized the cystic duct with the Heister valve from the common bile duct, and then two intra-hepatic biliary ducts of segment 5 (B5) were visualized from the neck of the gallbladder. There was a contrast medium filling defect in B5, which was considered to be due to an incarcerated stone. Magnetic resonance cholangiopancreatography (MRCP) and three-dimensional computed tomography (CT) cholangiography showed similar findings, suggesting that the patient had a biliary anomaly of the cystohepatic duct in which two intrahepatic bile ducts (B5) flowed into the neck of the gallbladder and a stone incarcerated in the neck of the gallbladder. At surgery, during mobilization of the gallbladder, there was a thick string between the liver and the gallbladder, and this was considered to be the junction of B5 with the gallbladder. Therefore, the neck of the gallbladder was cut, and an incarcerated stone 10 mm in diameter was removed. Intraoperative cholangiography revealed that the cystohepatic ducts were preserved. The postoperative course was uneventful and there was no bile leakage or liver dysfunction. Although cystohepatic duct is a rare biliary anomaly, the surgeon should be alert for its possible presence during cholecystectomy. When cholecystectomy is scheduled, more than one preoperative examination by three-dimensional CT cholangiography, MRCP or ERCP should be performed, and the surgeon should be careful not to overlook any biliary anomaly. Keywords: cystohepatic duct, biliary duct anomaly, cholecystectomy, three-dimensional computed tomography, gallstone