S Okada

Kagawa University, Miki, Hyogo-ken, Japan

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Publications (11)11.06 Total impact

  • Nippon Shokakibyo Gakkai zasshi The Japanese journal of gastro-enterology 04/2000; 97(3):337-41.
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    ABSTRACT: Serum hyaluronate can be used as an index of hepatic sinusoidal endothelial cell function. This study was designed to evaluate its application as a predictor of liver failure after major hepatectomy. Thirty-six patients who underwent right liver lobectomy after percutaneous transhepatic right branch portal vein embolization were divided into two groups based on their postoperative clinical course (groups 1 and 2, with and without postoperative liver failure, n = 6 and n = 30, respectively). We serially measured serum hyaluronate levels using a sandwich binding protein assay system before and after hepatectomy and determined relations with progression of the underlying chronic liver disorder, portal venous pressure, and liver growth of the left lobe after portal embolization. Serum hyaluronate levels were significantly elevated, in line with the degree of severity of the underlying chronic liver disorder, and correlated well with the portal venous pressure and the hypertrophic ratio of the left lobe subsequent to portal embolization. Serum hyaluronate levels in group 1 were significantly higher than those in group 2 before surgery and increased steeply during the early period after hepatectomy. These results suggest that the serum hyaluronate reflects the hepatic functional reserve, and serial measurement of this parameter after hepatectomy can serve as a simple indicator for early detection of posthepatectomy liver failure.
    World Journal of Surgery 04/2000; 24(3):359-64. · 2.23 Impact Factor
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    ABSTRACT: Hepatoduodenal ligamentectomy (ligamentectomy) is the ultimate surgery for biliary tract carcinoma involving perioperative difficulties such as total hepatic ischemia during revascularization of the hepatic artery and the portal vein, patency of the reconstructed hepatic artery, and high incidence of related operative mortality. In the present study, modified ligamentectomies with extended right hepatic lobectomy, including resection of the caudate lobe, were performed on three patients with advanced biliary tract carcinoma in whom the left hepatic artery had been replaced and the original artery was preserved. In all patients, postoperative courses were uneventful: success of the resection was confirmed by histological examination. This procedure enabled en bloc resection of hepatoduodenal ligament with positive cancer invasion to take place. It was carried out safely without concern for the difficulties described above. In our view, ligamentectomy should be performed in all such cases.
    Journal of Hepato-Biliary-Pancreatic Surgery 02/1998; 5(3):297-302. · 1.60 Impact Factor
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    ABSTRACT: We report herein the case of a patient who had previously undergone a lateral segmentectomy for hepatocellular carcinoma (HCC) in whom recurrent HCC invading the trunk of the right and middle hepatic veins in a damaged liver was treated by reconstruction of both hepatic veins, using total vascular exclusion with extracorporeal bypass and hypothermic hepatic perfusion. Reconstruction was performed using a graft taken from the left external iliac vein and divided into two pieces. Hepatic ischemia lasted for 91 min during the procedure and the intrahepatic temperature, as monitored by inserting a needle-type thermometer, was decreased to 11 degrees C throughout the procedure. The peak levels of serum glutamic pyruvic transaminase, lactate dehydrogenase, and total bilirubin were 363 IU/l, 1198 IU/ml, and 2.8 mg/dl, respectively, on postoperative day (POD) 2. The patient's postoperative course was uneventful except for mild, temporary swelling of the left leg. Postoperative computed tomography and magnetic resonance imaging examinations disclosed no obstruction of either graft, and the patient was discharged on POD 40.
    Surgery Today 02/1998; 28(5):547-50. · 0.96 Impact Factor
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    ABSTRACT: With the aim of minimizing postoperative liver dysfunction and promoting increased resectability, we employed portal vein embolization (PVE). In this study, the effect of PVE on major hepatic resection for advanced-stage hepatocellular carcinoma (HCC) in injured livers was evaluated. PVE was performed prior to hepatectomy in 13 patients with stage III and IV HCCs. Following PVE, right trisegmentectomy was performed in 3 patients, extended right lobectomy in 3 and right lobectomy in 7. To evaluate the effect of PVE, the changes in liver functional capacity and estimated remnant liver volume (ERLV), determined by computed tomography, were examined before and after PVE. The operative morbility, mortality, and survival rates after hepatectomy were also assessed. By 2 weeks after PVE, ERLV had increased in all patients, by an average of 28%, and the mean resection rates had decreased from 70.0% to 62.2%. Postoperatively, the 30-day mortality rate was 15.3%, and the 1- and 2-year survival rates were 69% and 46%, respectively. The results of this study indicate that resectability can be increased, and major hepatectomy can be made safer by employing PVE preoperatively, in view of the fact that major hepatectomy was not considered feasible without PVE in these patients.
    Surgery Today 02/1997; 27(5):403-10. · 0.96 Impact Factor
  • Transplantation Proceedings 03/1996; 28(1):331-2. · 0.95 Impact Factor
  • Transplantation Proceedings 03/1996; 28(1):68-9. · 0.95 Impact Factor
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    ABSTRACT: To determine whether cytokines produced in the operative field during digestive surgery selectively spill over into the portal blood, the changes in interleukin-6 (IL-6) levels in portal and peripheral venous blood were assayed at several points in time from the commencement of surgery until 14 days later, in 11 patients. Similar changes in the IL-6 levels were observed in the portal and peripheral blood samples; however, the IL-6 levels in the portal blood reached a maximum 6-12h after the commencement of surgery, being earlier than in the peripheral venous blood. In fact, between 3 and 12h after the commencement of surgery, the IL-6 levels were higher in the portal blood by 33-81 pg/ml. By 24h or more after the commencement of surgery, the IL-6 levels did not differ significantly in the two types of blood samples. Moreover, the C-reactive protein levels 2 days after surgery were even more closely correlated to the maximum IL-6 levels in the portal blood than to those in the peripheral venous blood. These results suggest that IL-6 produced during intra-abdominal digestive surgery initially enters the portal blood, being trapped by IL-6 receptors in the liver, where it may regulate the synthesis of acute-phase proteins as a hepatocyte-stimulating factor.
    Surgery Today 02/1996; 26(11):890-4. · 0.96 Impact Factor
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    ABSTRACT: The early prognosis of the hepatectomized patients with hepatocellular carcinoma was determined preoperatively with a perceptron-type neural network. The neural network was trained with the preoperative data of 54 example cases with the early prognosis, successful or died of hepatic dysfunction, as teaching signals. After learning these examples, the neural network came to give a precise prediction to the example data except for one case. With the learned neural network, the outcomes of the hepatectomy of 11 patients (10 successful; 1 died) were predicted prospectively with 100% precision. The usefulness of the neural network for the prediction was determined.
    Computers in Biology and Medicine 02/1995; 25(1):49-59. · 1.48 Impact Factor
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    ABSTRACT: We report herein the case of a 20-year-old woman in whom an enormous aneurysmal portahepatic venous fistula was found. The portal aneurysm developed in the anterior inferior segment of the right hepatic lobe, and communicated with the right portal vein and the right hepatic vein. Due to the enormous size of the shunt, and because the patient's venous blood ammonia level increased by about twofold after eating, a right lobectomy of the liver was performed. A review of the available literature and a discussion of the most appropriate treatment follows the presentation of this case.
    Surgery Today 02/1995; 25(9):855-8. · 0.96 Impact Factor
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    ABSTRACT: In temporary, permanent or extra-anatomic bypass grafting to the side of the ascending aorta, a technique of prosthetic fabric wrapping of the ascending aorta associated with reinforcement of the anastomosis is devised as a simple and useful method for aortic surgery. With this technique, dislodgement of the vascular forceps can be prevented completely, and the ascending aortic wall may be protected from injuries owing to the vascular forceps.
    Kyobu geka. The Japanese journal of thoracic surgery 09/1989; 42(9):746-8.