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Dive into the research topics where Yasutsugu Bandai is active.

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Featured researches published by Yasutsugu Bandai.


British Journal of Surgery | 2010

Fluorescent cholangiography illuminating the biliary tree during laparoscopic cholecystectomy

Takeaki Ishizawa; Yasutsugu Bandai; Masayoshi Ijichi; Junichi Kaneko; Kiyoshi Hasegawa; Norihiro Kokudo

Although intraoperative cholangiography has been recommended for avoiding bile duct injury during laparoscopic cholecystectomy, radiographic cholangiography is time consuming and may itself cause injury to the bile duct. Recently, a novel fluorescent cholangiography technique using the intravenous injection of indocyanine green (ICG) has been developed.


Surgical Endoscopy and Other Interventional Techniques | 1993

Changes in splanchnic blood flow and cardiovascular effects following peritoneal insufflation of carbon dioxide

Yoichi Ishizaki; Yasutsugu Bandai; Kazuyuki Shimomura; Hideki Abe; Yumiko Ohtomo; Yasuo Idezuki

SummaryLaparoscopic surgery has rapidly become a popular and widely used technique. Although this procedure has been shown to be generally safe, cardiovascular derangement related to carbon dioxide pneumoperitoneum has been reported. There are few data available on the relationship between systemic and regional hemodynamics in cases of pneumoperitoneum. Changes in splanchnic blood flow and cardiovascular effects following a moderate increase of intraabdominal pressure (IAP) to 16 mmHg during a 3-h period were analyzed in six anesthetized dogs. After insufflation, cardiac output and blood flow in the superior mesenteric artery and portal vein decreased progressively and returned to the preinsufflation values following deflation. Hepatic arterial blood flow did not change significantly, perhaps due to compensatory mechanisms for maintenance of hepatic blood flow. Mechanical compression of the splanchnic capillary beds due to the elevated IAP may possibly reflect the increase in systemic vascular resistance causing the decrease in cardiac output. To prevent this impairment, intermittent decompression of gas during surgical laparoscopy is recommended.


Archives of Surgery | 2009

Fluorescent Cholangiography Using Indocyanine Green for Laparoscopic Cholecystectomy: An Initial Experience

Takeaki Ishizawa; Yasutsugu Bandai; Norihiro Kokudo

I ntraoperative cholangiography (IOC) is recommended to prevent bile duct injury during laparoscopic cholecystectomy. However, conventional radiographic IOC in a laparoscopic setting is timeconsuming, and insertion of a transcystic tube for contrastmaterial injection may in itself cause bile duct injury. Furthermore, conventional IOC exposes the patient and medical staff to radiation and usually requires a large fluoroscopy machine and additional human resources. Recently, we developed a novel fluorescent IOC technique using the intravenous injection of indocyanine green (ICG) to delineate the biliary tract during an open cholecystectomy. Herein, we report our initial experience applying fluorescent IOC to laparoscopic cholecystectomy using a newly devised laparoscopic fluorescent imaging system. Our fluorescent IOC technique is based on the principle that ICG is excreted into bile and that proteinbound ICG emits light with a peak wavelength of approximately 830 nm when illuminated with nearinfrared light. The prototypic fluorescent imaging system (Hamamatsu Photonics Co, Hamamatsu, Japan) is composed of a xenon light source, a small control unit, and a laparoscope (10 mm in diameter) with a chargecoupled device camera, which can filter out light with wavelengths below 810 nm. This imaging system has originally been used for sentinel node biopsies during gastrointestinal surgery.


Annals of Surgery | 1995

Segmental occlusion of the pancreatic duct with prolamine to prevent fistula formation after distal pancreatectomy.

Toshiro Konishi; Mamoru Hiraishi; Keiichi Kubota; Yasutsugu Bandai; Masatoshi Makuuchi; Yasuo Idezuki

ObjectiveThe authors used prolamine (Ethibloc, Ethicon GmBH, Norderstedt, Germany) for segmental obstruction of the pancreatic duct to prevent pancreatic fistula development after distal pancreatectomy combined with total gastrectomy for gastric malignancies. Summary Background DataSummary Background Data the initial clinical application of prolamine was pancreatic duct obstruction for patients with pancreatitis and undergoing pancreatic transplantation and pancreaticoduodenectomy for pancreatic cancer, there are no reports on prevention of pancreatic fistula formation after distal pancreatectomy. MethodsProlamine (0.2 mL) was injected into the distal segment of the main duct in the remaining pancreata of 51 patients. Small pancreatic ducts on the cut surface, from which prolamine extravasates, were closed by ligation, the main duct was ligated doubly, and the transected pancreatic margin was closed 15 minutes after phenylpropanolamine hydrochloride injection. ResultsResults patient developed a pancreatic fistula or the complication of arterial bleeding due to prolonged infection. ConclusionConclusion obstruction of the pancreatic duct with prolamine is useful for preventing pancreatic fistula development after distal pancreatectomy.


Gastroenterology | 1992

Direct evidence for the intact hepatocyte theory in patients with liver cirrhosis

Seiji Kawasaki; Hiroshi Imamura; Yasutsugu Bandai; Kensho Sanjo; Yasuo Idezuki

An attempt was made to compare various morphometric parameters, including total hepatocyte number, with the in vivo clearances of aminopyrine and antipyrine in 26 cirrhotic and 14 noncirrhotic patients to evaluate the intact hepatocyte theory. Morphometric analysis was performed with a newly developed method using a computer-aided color image analyzer. Aminopyrine clearance was significantly correlated with liver volume (r = 0.434; P less than 0.05), parenchymal cell volume (r = 0.574; P less than 0.001), and most strongly with total hepatocyte number (r = 0.614; P less than 0.001) in all patients. Significant correlations were also observed between these three parameters and antipyrine clearance (r = 0.367, P less than 0.05; r = 0.663, P less than 0.001; and r = 0.807, P less than 0.001, respectively). The mean aminopyrine clearance per individual hepatocyte showed no significant difference between cirrhotic and noncirrhotic patients (3.52 +/- 1.60 x 10(-10) mL/min vs. 3.65 +/- 1.50 x 10(-10) mL/min, respectively; P greater than 0.10). Similar results were obtained for antipyrine clearance per hepatocyte (7.35 +/- 2.27 x 10(-11) mL/min for cirrhotics vs. 6.16 +/- 1.07 x 10(-11) mL/min for noncirrhotics; P greater than 0.10). Thus, the intrinsic clearances of drugs per individual hepatocyte, as originally proposed in the intact cell hypothesis, were directly evaluated for the first time, lending strong support to the intact hepatocyte theory.


Asian Journal of Endoscopic Surgery | 2010

Indocyanine green‐fluorescent imaging of hepatocellular carcinoma during laparoscopic hepatectomy: An initial experience

Takeaki Ishizawa; Yasutsugu Bandai; Nobuhiro Harada; Arata Muraoka; Masayoshi Ijichi; K Kusaka; Masayuki Shibasaki; Norihiro Kokudo

Introduction: Laparoscopic hepatectomy has disadvantages in intraoperative diagnosis, because it offers limited visualization and palpability of the liver surface. Recently, we developed a novel fluorescent imaging technique using indocyanine green (ICG), which would enable identification of liver cancers during open hepatectomy. However, this technique has not yet been applied to laparoscopic hepatectomy.


Controlled Clinical Trials | 1996

A world wide web-based user interface for a data management system for use in multi-institutional clinical trials—Development and experimental operation of an automated patient registration and random allocation system

Takahiro Kiuchi; Yasuo Ohashi; Masaru Konishi; Yasutsugu Bandai; Tomoo Kosuge; Tadao Kakizoe

We have employed the Hypertext Transfer Protocol (HTTP) and Hypertext Markup Language (HTML) to develop an automated patient registration and random allocation system for use in a multi-institutional clinical trial. We made it available on-line to World Wide Web clients in each hospital through a user friendly graphical user interface. During experimental operation, the physicians found it satisfactory from the viewpoint of both ease of operation and response time. For the development of a graphical user interface in network-based information system for use in multi-institutional clinical trials, HTTP/HTML has several advantages over an ordinary client-server model. Therefore, we concluded that we would adopt HTP/HTML for the construction of user interfaces for physicians in each spital and for data managers in our coordinating center.


Medicine | 2015

Techniques of Fluorescence Cholangiography During Laparoscopic Cholecystectomy for Better Delineation of the Bile Duct Anatomy.

Yoshiharu Kono; Takeaki Ishizawa; Keigo Tani; Nobuhiro Harada; Junichi Kaneko; Akio Saiura; Yasutsugu Bandai; Norihiro Kokudo

Abstract To evaluate the clinical and technical factors affecting the ability of fluorescence cholangiography (FC) using indocyanine green (ICG) to delineate the bile duct anatomy during laparoscopic cholecystectomy (LC). Application of FC during LC began after laparoscopic fluorescence imaging systems became commercially available. In 108 patients undergoing LC, FC was performed by preoperative intravenous injection of ICG (2.5 mg) during dissection of Calots triangle, and clinical factors affecting the ability of FC to delineate the extrahepatic bile ducts were evaluated. Equipment-related factors associated with bile duct detectability were also assessed among 5 laparoscopic systems and 1 open fluorescence imaging system in ex vivo studies. FC delineated the confluence between the cystic duct and common hepatic duct (CyD–CHD) before and after dissection of Calots triangle in 80 patients (74%) and 99 patients (92%), respectively. The interval between ICG injection and FC before dissection of Calots triangle was significantly longer in the 80 patients in whom the CyD–CHD confluence was detected by fluorescence imaging before dissection (median, 90 min; range, 15–165 min) than in the remaining 28 patients in whom the confluence was undetectable (median, 47 min; range, 21–205 min; P < 0.01). The signal contrast on the fluorescence images of the bile duct samples was significantly different among the laparoscopic imaging systems and tended to decrease more steeply than those of the open imaging system as the target-laparoscope distance increased and porcine tissues covering the samples became thicker. FC is a simple navigation tool for obtaining a biliary roadmap to reach the “critical view of safety” during LC. Key factors for better bile duct identification by FC are administration of ICG as far in advance as possible before surgery, sufficient extension of connective tissues around the bile ducts, and placement of the tip of laparoscope close and vertically to Calots triangle.


Surgical Endoscopy and Other Interventional Techniques | 1994

Role of laparoscopic cholecystectomy in treating gallbladder polyps.

Keisuke Kubota; Yasutsugu Bandai; Y. Otomo; A. Ito; Masahiko Watanabe; H. Toyoda; Yasuo Idezuki

Since the application of laparoscopic cholecystectomy (Lap C) to gallbladder polyps has not yet been fully evaluated, we performed Lap C on 26 patients with gallbladder polyps. Pathological examinations showed adenocarcinoma in three patients, adenoma in two, and cholesterol polyp in 21. Preoperative diagnoses of the cases with adenocarcinoma were a cholesterol polyp in one patient and an adenoma in two. Adenocarcinoma was confirmed to reside in the mucosa without any invasion of lymphatic ducts or small vessels in the three patients. This procedure was considered to be sufficient for this grade of cancer, and, therefore, no additional operations were performed. At present, our policy is to resect by Lap C a gallbladder polyp having a maximum size larger than 10 mm and a tendency to grow or presenting with suspicion of adenoma. When cancer is suspected by preoperative examinations, however, traditional surgery may be recommended.


Ultrasound in Medicine and Biology | 1984

Ultrasonically guided cholangiography and bile drainage

Masatoshi Makuuchi; Susumu Yamazaki; Hiroshi Hasegawa; Yasutsugu Bandai; Toru Ito; Goro Watanabe

Ultrasonically guided percutaneous transhepatic cholangiography (UG-PTC), bile drainage (UG-PTBD) and gallbladder drainage procedure (UG-PTGBD), developed by us, were performed in 47, 183 and 36 patients, respectively. In 47 patients UG-PTC was successfully performed 51 times without complications. By UG-PTBD 220 intubations were carried out successfully and four attempts failed (1.8%). The main complication was that the catheter slipped out from the bile duct. It was experienced 27 times (12.3%) in 23 patients (12.4%) from two to 47 days after intubation. UG-PTGBD was successfully performed 36 times. Bleeding from the catheter was experienced in four patients. However, other complications such as cholascos were not experienced. Due to the development of ultrasonic diagnosis and the UG-PTBD procedure, the indications for percutaneous transhepatic cholangiography (PTC) are now limited. For differentiation of jaundice, ultrasonic examination takes over from PTC. For preparation of PTBD, thin needle cholangiography is no longer necessary because UG-PTBD is a single-step procedure without the need for cholangiography. Therefore, the indication for PTC is limited to patients with partial dilatation of intrahepatic bile ducts without jaundice, for example when only the left hepatic duct is dilated due to hepatolithiasis.

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Keiichi Kubota

Dokkyo Medical University

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