Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Tsukasa Takayashiki is active.

Publication


Featured researches published by Tsukasa Takayashiki.


Journal of Hepato-biliary-pancreatic Surgery | 2008

Usefulness of intraoperative fluorescence imaging to evaluate local anatomy in hepatobiliary surgery.

Noboru Mitsuhashi; Fumio Kimura; Hiroaki Shimizu; Mizuho Imamaki; Hiroyuki Yoshidome; Masayuki Ohtsuka; Atsushi Kato; Hideyuki Yoshitomi; Satoshi Nozawa; Katsunori Furukawa; Dan Takeuchi; Tsukasa Takayashiki; Kosuke Suda; Tatsuo Igarashi; Masaru Miyazaki

BACKGROUND/PURPOSE One of the major complications encountered in hepatobiliary surgery is the incidence of bile duct and blood vessel injuries. It is sometimes difficult during surgery to evaluate the local anatomy corresponding to hepatic arteries and bile ducts. We investigated the potential utility of an infrared camera system as a tool for evaluating local anatomy during hepatobiliary surgery. METHODS An infrared camera system was used to detect indocyanine green fluorescence in vitro. We also employed this system for the intraoperative fluorescence imaging of the arteries and biliary system in a pig. Further, we evaluated blood flow in the hepatic artery, portal vein, and liver parenchyma during a human liver transplant and we investigated local anatomy in patients undergoing cholecystectomy. RESULTS Fluorescence confirmed that indocyanine green was distributed in serum and bile. In the pig study, we confirmed the fluorescence of the biliary system for more than 1 h. In the liver transplant recipient, blood flow in the hepatic artery and portal vein was confirmed around the anastomosis. In most of the patients undergoing cholecystectomy, fluorescence was observed in the gallbladder, cystic and common bile ducts, and hepatic and cystic arteries. CONCLUSIONS Intraoperative fluorescence imaging in hepatobiliary surgery facilitates better understanding of the anatomy of arteries, the portal vein, and bile ducts.


The American Journal of Surgical Pathology | 2011

Similarities and differences between intraductal papillary tumors of the bile duct with and without macroscopically visible mucin secretion.

Masayuki Ohtsuka; Fumio Kimura; Hiroaki Shimizu; Hiroyuki Yoshidome; Atsushi Kato; Hideyuki Yoshitomi; Katsunori Furukawa; Dan Takeuchi; Tsukasa Takayashiki; Kosuke Suda; Shigetsugu Takano; Yoichiro Kondo; Masaru Miyazaki

Intraductal papillary neoplasms of the bile duct (IPNB) have been recently proposed as the biliary counterpart of intraductal papillary mucinous neoplasms of the pancreas (IPMN-P). However, in contrast to IPMN-P, IPNB include a considerable number of the tumors without macroscopically visible mucin secretion. Here we report the similarities and differences between IPNB with and without macroscopically visible mucin secretion (IPNB-M and IPNB-NM). Surgically resected 27 consecutive cases with IPNB were divided into IPNB-M (n=10) and IPNB-NM (n=17), and their clinicopathologic features were examined. Clinically, both tumors were similar. Pathologically, the most frequent histopathologic types were pancreatobiliary in IPNB-NM and intestinal in IPNB-M. Various degrees of cytoarchitectural atypia within the same tumor were exhibited in 8 IPNB-M, but only 3 in IPNB-NM. Although the tumor size was similar, 9 IPNB-NM were invasive carcinoma, whereas all but 1 IPNB-M with carcinoma were in situ or minimally invasive. Immunohistochemically, positive MUC2 expression was significantly more frequent in IPNB-M than in IPNB-NM, whereas MUC1 tended to be more frequently expressed in IPNB-NM compared with IPNB-M. Among IPNB-NM with positive MUC1 expression, 3 had negative MUC2 and MUC5AC expressions. These tumors showed a tubulopapillary growth with uniform degree of cytoarchitectural atypia. All IPNB-M were negative for p53, and the frequency of positive p53 protein in IPNB-NM was at the middle level of that in IPNB-M and nonpapillary cholangiocarcinoma. In conclusion, IPNB-M showed striking similarities to IPMN-P, but IPNB-NM contained heterogeneous disease groups.


Journal of Hepato-biliary-pancreatic Sciences | 2010

One hundred seven consecutive surgical resections for hilar cholangiocarcinoma of Bismuth types II, III, IV between 2001 and 2008.

Masaru Miyazaki; Fumio Kimura; Hiroaki Shimizu; Hiroyuki Yoshidome; Masayuki Otuka; Kato A; Hideyuki Yoshitomi; Katsunori Furukawa; Dan Takeuchi; Tsukasa Takayashiki; Suda K; Shigetugu Takano

Many authors at high-volume centers all over the world have reported improved outcomes of hilar cholangiocarcinoma by several aggressive surgical approaches such as extended hepatic resection, combined vascular resection, and hepatopancreaticoduodenectomy in recent years. There has been great progress in the surgical treatment of hilar cholangiocarcinoma with these previous efforts by aggressive hepatobiliary surgeons. In particular, surgical techniques, diagnostic modalities, and perioperative management have been remarkably improved as compared with before. Herein we report the surgical outcome for both hilar cholangiocarcinoma of Bismuth types II, III, and IV and intrahepatic cholangiocarcinoma involving the hepatic duct confluence during the recent 8-year period between 2001 and 2008 at our institution, the Department of General Surgery at Chiba University. From our recent experienced results, it can be concluded that the surgical strategy for hilar cholangiocarcinoma has been improved remarkably, and major surgical hepatectomy can be done with relative safety, and these aggressive surgical approaches, including combined vascular resection, may be warranted for the surgical treatment of hilar cholangiocarcinoma. However, the adoption of new innovative therapeutic approaches might be required for further improvement of surgical outcome of hilar cholangiocarcinoma.


Journal of Hepato-biliary-pancreatic Sciences | 2015

Clinical practice guidelines for the management of biliary tract cancers 2015: the 2nd English edition

Masaru Miyazaki; Hideyuki Yoshitomi; Shuichi Miyakawa; Katsuhiko Uesaka; Michiaki Unno; Itaru Endo; Takehiro Ota; Masayuki Ohtsuka; Hisafumi Kinoshita; Kazuaki Shimada; Hiroaki Shimizu; Masami Tabata; Kazuo Chijiiwa; Masato Nagino; Satoshi Hirano; Toshifumi Wakai; Keita Wada; Hiroyuki Iasayama; Takuji Okusaka; Toshio Tsuyuguchi; Naotaka Fujita; Junji Furuse; Kenji Yamao; Koji Murakami; Hideya Yamazaki; Hiroshi Kijima; Yasuni Nakanuma; Masahiro Yoshida; Tsukasa Takayashiki; Tadahiro Takada

The Japanese Society of Hepato‐Biliary‐Pancreatic Surgery launched the clinical practice guidelines for the management of biliary tract and ampullary carcinomas in 2008. Novel treatment modalities and handling of clinical issues have been proposed after the publication. New approaches for editing clinical guidelines, such as the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system, also have been introduced for better and clearer grading of recommendations.


Journal of Hepato-biliary-pancreatic Sciences | 2014

Recent advances and problems in the management of pancreaticobiliary maljunction: feedback from the guidelines committee

Terumi Kamisawa; Hisami Ando; Mitsuo Shimada; Yoshinori Hamada; Takao Itoi; Tsukasa Takayashiki; Masaru Miyazaki

Clinical practice guidelines on how to deal with pancreaticobiliary maljunction (PBM) were made in Japan in 2012, representing a world first. Using a narrow definition, congenital biliary dilatation involves only Todani type I (except type Ib) and type IV‐A, both of which are accompanied by PBM in almost all cases. Prospective ultrasonographic study revealed that the maximum diameter of the common bile duct increased with age. Pathophysiological conditions due to pancreatobiliary reflux occur in patients with high confluence of the pancreaticobiliary ducts, a common channel ≥6 mm long and occlusion of communication during contraction of the sphincter of Oddi. Since PBM can be diagnosed by magnetic resonance cholangiopancreatography, multi‐planar reconstruction multi‐detector row computed tomography and endoscopic ultrasonography, the current diagnostic criteria should be revised to take these diagnostic imaging modalities into consideration. According to a nationwide survey, biliary cancer occurred in 21.6% of adult patients with PBM with biliary dilatation and 42.2% of patients with PBM without biliary dilatation. In biliary cancer associated with PBM without biliary dilatation, 88.1% were gallbladder cancer. Treatment for PBM with biliary dilatation is prophylactic flow‐diversion surgery, but further investigations and surveillance studies are needed to clarify the appropriate surgical strategy for PBM without biliary dilatation.


Journal of Hepato-biliary-pancreatic Sciences | 2014

Preoperative diagnosis and surgical management for solid pseudopapillary neoplasm of the pancreas

Isamu Hosokawa; Hiroaki Shimizu; Masayuki Ohtsuka; Atsushi Kato; Hideyuki Yoshitomi; Katsunori Furukawa; Tsukasa Takayashiki; Takeshi Ishihara; Osamu Yokosuka; Masaru Miyazaki

Preoperative diagnosis of solid pseudopapillary neoplasm of the pancreas (SPN) remains difficult and optimal surgical management for SPN has yet to be fully defined.


Hepato-gastroenterology | 2011

Usefulness of preoperative partial splenic embolization in hepatocellular carcinoma and hypersplenic thrombocytopenia.

Hiroyuki Yoshidome; Fumio Kimura; Hiroaki Shimizu; Masayuki Ohtsuka; Kato A; Hideyuki Yoshitomi; Furukawa K; Dan Takeuchi; Tsukasa Takayashiki; Suda K; Shigetsugu Takano; Masaru Miyazaki

BACKGROUND/AIMS Patients with both hepatocellular carcinoma and hypersplenic thrombocytopenia are occasionally seen and this condition can severely complicate liver resection. This study evaluated the usefulness of preoperative partial splenic embolization (PSE) as an alternative to splenectomy (SP). METHODOLOGY Twenty-eight patients with hypersplenic thrombocytopenia underwent hepatectomy for hepatocellular carcinoma. Five patients underwent preoperative PSE and 23 patients underwent concomitant splenectomy. The blood cell counts, laboratory chemistry data, and operative morbidity, prognosis were all examined. RESULTS There were no severe PSE-related complications such as splenic abscess seen after PSE. The platelet counts in the PSE group significantly increased in comparison to those in the SP group before the operation. The frequency of blood transfusion and postoperative complications in the PSE group was significantly less than that in the SP group. The duration of surgery, blood loss, and performance of PSE were significant factors to predict postoperative complications. The overall survival after liver resection was not significantly different between patients in the PSE and SP group. CONCLUSIONS Preoperative PSE could be safely performed without severe adverse effects prior to liver resection and it was thus considered to be useful for increasing the number of platelets and reducing postoperative complications.


World Journal of Gastroenterology | 2015

Peripheral portal vein-oriented non-dilated bile duct puncture for percutaneous transhepatic biliary drainage

Hiroaki Shimizu; Atsushi Kato; Tsukasa Takayashiki; Satoshi Kuboki; Masayuki Ohtsuka; Hideyuki Yoshitomi; Katsunori Furukawa; Masaru Miyazaki

AIM To evaluate the efficacy of peripheral portal vein (PV)-oriented non-dilated bile duct (BD) puncture for percutaneous transhepatic biliary drainage (PTBD). METHODS Thirty-five patients with non-dilated BDs underwent PTBD for the management of various biliary disorders, including benign bilioenteric anastomotic stricture (n = 24), BD stricture (n = 5) associated with iatrogenic BD injury, and postoperative biliary leakage (n = 6). Under ultrasonographic guidance, percutaneous transhepatic puncture using a 21-G needle was performed along the running course of the peripheral targeted non-dilated BD (preferably B6 for right-sided approach, and B3 for left-sided approach) or along the accompanying PV when the BD was not well visualized. This technique could provide an appropriate insertion angle of less than 30° between the puncture needle and BD running course. The puncture needle was then advanced slightly beyond the accompanying PV. The needle tip was moved slightly backward while injecting a small amount of contrast agent to obtain the BD image, followed by insertion of a 0.018-inch guide wire (GW). A drainage catheter was then placed using a two-step GW method. RESULTS PTBD was successful in 33 (94.3%) of the 35 patients with non-dilated intrahepatic BDs. A right-sided approach was performed in 25 cases, while a left-sided approach was performed in 10 cases. In 31 patients, the first PTBD attempt proved successful. Four cases required a second attempt a few days later to place a drainage catheter. PTBD was successful in two cases, but the second attempt also failed in the other two cases, probably due to poor breath-holding ability. Although most patients (n = 26) had been experiencing cholangitis with fever (including septic condition in 8 cases) before PTBD, only 5 (14.3%) patients encountered PTBD procedure-related complications, such as transient hemobilia and cholangitis. No major complications such as bilioarterial fistula or portal thrombosis were observed. There was no mortality in our series. CONCLUSION Peripheral PV-oriented BD puncture for PTBD in patients with non-dilated BDs is a safe and effective procedure for BD stricture and postoperative bile leakage.


Journal of Hepato-biliary-pancreatic Sciences | 2014

Tips and tricks of surgical technique for pancreatic cancer: portal vein resection and reconstruction (with videos)

Hideyuki Yoshitomi; Atsushi Kato; Hiroaki Shimizu; Masayuki Ohtsuka; Katsunori Furukawa; Tsukasa Takayashiki; Satoshi Kuboki; Shigetsugu Takano; Daiki Okamura; Daisuke Suzuki; Nozomu Sakai; Shingo Kagawa; Masaru Miyazaki

Surgical resection is the only hope for cure in patients with pancreatic cancer. To improve the resectability and achieve better prognosis of this lethal disease, extended resection for pancreatic cancer has been applied. We have performed portal vein resection aggressively for pancreatic cancer with portal vein invasion. We also established a method of portal vein reconstruction using the left renal vein graft for tumors widely extended to the portal vein. Our data show similar survival between patients with portal vein obstruction and those without invasion. We also show that portal vein reconstruction using the left renal vein graft can be performed safely without severe liver damage. With video, we introduce our surgical technique for portal vein resection and reconstruction, especially focusing on the usage of the left renal vein graft, providing several tips for a safe and successful procedure.


Transplant International | 2014

Protective effects of simultaneous splenectomy on small‐for‐size liver graft injury in rat liver transplantation

Takuya Yoichi; Tsukasa Takayashiki; Hiroaki Shimizu; Hiroyuki Yoshidome; Masayuki Ohtsuka; Atsushi Kato; Hideyuki Yoshitomi; Katsunori Furukawa; Satoshi Kuboki; Daiki Okamura; Daisuke Suzuki; Masayuki Nakajima; Masaru Miyazaki

Splenectomy is an effective technique in living donor liver transplantation (LDLT) with small‐for‐size (SFS) liver grafts for overcoming SFS liver graft injury. However, the protective mechanism of splenectomy is still unclear. The aim of this study was to investigate how splenectomy could attenuate SFS graft injury through the measurement of biochemical factors, particularly the expression of endothelin (ET)‐1, which is a key molecule of microcirculatory disorders by mediating sinusoidal vasoconstriction. We performed rat orthotopic liver transplantation using SFS liver grafts with or without splenectomy. We investigated intragraft expression of ET‐1 mRNA and hepatic protein levels of ET‐1. In addition, portal pressure, hepatic injury and morphological changes, and survival rate were evaluated. In result, intragraft ET‐1 mRNA expression after SFS liver transplantation was significantly downregulated by splenectomy, and hepatic expression of ET‐1 in SFS grafts was rarely observed. Splenectomy inhibited the increase in portal pressure, ameliorated SFS liver graft injury and improved the graft survival rate after SFS liver transplantation. In conclusion, splenectomy improved the SFS liver injury and decreased the expression of ET‐1 by attenuating portal hypertension on SFS liver transplantation. Downregulation of intragraft ET‐1 expression plays important roles in the protective mechanism of splenectomy in SFS liver transplantation.

Collaboration


Dive into the Tsukasa Takayashiki's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Atsushi Kato

University of Louisville

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge