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Dive into the research topics where Yasuhiro Takase is active.

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Featured researches published by Yasuhiro Takase.


Digestive Surgery | 2001

Correlation between Endoscopic and Angiographic Findings in Patients with Esophageal and Isolated Gastric Varices

Fumio Chikamori; Nobutoshi Kuniyoshi; Susumu Shibuya; Yasuhiro Takase

Background/Aim: The correlation between angiographic vascular patterns and endoscopic findings in portal hypertension is not sufficiently known, and knowledge of the vascular anatomy may contribute to an improvement in endoscopic embolization and transjugular retrograde obliteration procedures. We propose a new vascular map that should prove useful for this purpose. Methods: Between April 1985 and December 1997 we performed percutaneous transhepatic portography in a selected group of 75 patients (16 women and 59 men), aged 43–71 years, from whom informed consent was obtained. All patients had been diagnosed endoscopically as having either esophageal or isolated gastric varices. According to the Child-Pugh classification, class A, B, and C cirrhosis was seen in 19, 40, and 16 patients, respectively. We created a vascular map of esophageal and isolated gastric varices, based on the opacification of the portal venous collaterals on percutaneous transhepatic portography. We compared the patients in both variceal groups in terms of portal venous pressure, main blood supply, and drainage routes. Results: We found that the portal collateral system was divided into two systems: the portoazygos venous system and the portophrenic venous system. The former contributed to the formation of esophageal and cardiac varices and the latter to the formation of isolated gastric varices located at the fundus or at both the cardia and fundus. The left gastric vein participated as blood supply in 70% of the isolated gastric varices and in 100% of the esophageal varices (p < 0.01). The posterior gastric vein participated as blood supply in 70% of the isolated gastric varices and in 24% of the esophageal varices (p < 0.01). We classified the main blood drainage routes of isolated gastric varices functionally into three types: gastrorenal shunt (85%), gastrophrenic shunt (10%), and gastropericardiac shunt (5%). The portal venous pressure in patients with esophageal varices was 358 ± 66 mm H2O, whereas in patients with isolated gastric varices it was 262 ± 44 mm H2O (p < 0.01). Conclusion: We suggest that this new vascular map will be useful in endoscopic embolization and transjugular retrograde obliteration procedures for esophageal and isolated gastric varices.


American Journal of Roentgenology | 2008

Gastric Varices with Gastrorenal Shunt: Combined Therapy Using Transjugular Retrograde Obliteration and Partial Splenic Embolization

Fumio Chikamori; Nobutoshi Kuniyoshi; Takahiko Kawashima; Yasuhiro Takase

OBJECTIVE This study was prospectively conducted to evaluate the effectiveness of the combination of transjugular retrograde obliteration and partial splenic embolization in the treatment of gastric varices with gastrorenal shunt. SUBJECTS AND METHODS Between November 2002 and December 2006, 14 patients with gastric varices and gastrorenal shunt were treated by combining transjugular retrograde obliteration and partial splenic embolization (group 1). These patients were compared with 19 patients with gastric varices and gastrorenal shunt treated by only transjugular retrograde obliteration (group 2) for the disappearance rate of gastric varices, the cumulative survival rate, and the occurrence rate of esophageal varices after transjugular retrograde obliteration. Partial splenic embolization was performed 7-14 days before transjugular retrograde obliteration. No significant differences were seen between the two groups in terms of demographic data, including age, sex, and Child-Pugh classification. RESULTS The disappearance rate of gastric varices after transjugular retrograde obliteration was 100% in both groups. The 3-year cumulative survival rate after transjugular retrograde obliteration was 92% in group 1 and 95% in group 2. The 3-year cumulative occurrence rate of esophageal varices after transjugular retrograde obliteration was 9% in group 1 and 45% in group 2, a significant difference (p < 0.05). CONCLUSION The findings of this study indicate that partial splenic embolization contributed to preventing portal congestion after transjugular retrograde obliteration. We conclude that the combination of transjugular retrograde obliteration and partial splenic embolization for gastric varices is more effective than transjugular retrograde obliteration only in the long-term prevention of esophageal varices after transjugular retrograde obliteration.


Digestive Surgery | 2000

Short-Term Hemodynamic Effects of Transjugular Retrograde Obliteration of Gastric Varices with Gastrorenal Shunt

Fumio Chikamori; Nobutoshi Kuniyoshi; Susumu Shibuya; Yasuhiro Takase

Objectives: The purpose of this study was to investigate the short-term effects on portal hemodynamics of transjugular retrograde obliteration (TJO) of gastric varices with gastrorenal shunt. Methods: Thirty patients with gastric varices and a gastrorenal shunt were included in this study. The patients ranged in age from 42 to 75 years (16 men and 14 women), and according to Child’s classification, class A, B and C cirrhosis was seen in 1, 13 and 16 patients, respectively. The portal blood flow was measured by an ultrasonic duplex Doppler system, and the wedged hepatic venous pressure was measured by hepatic venous catheterization, before and after TJO. Results: Complete obliteration of the gastrorenal shunt and gastric varices was revealed by retrograde inferior phrenic venography and computed tomography after TJO in all cases. The wedged hepatic venous pressure was significantly increased the day after TJO compared with that before therapy (257 ± 71 vs. 307 ± 73 mm H2O, p < 0.01). The portal venous flow was significantly increased 1 week after TJO compared with that before therapy (744 ± 190 vs. 946 ± 166 ml/min, p < 0.01). The serum albumin levels before and after TJO were 3.0 ± 0.4 and 3.1 ± 0.5 g/dl, respectively, and the total bilirubin levels were 1.5 ± 0.7 and 1.5 ± 0.8 mg/dl, respectively, neither of these parameters changing significantly. The plasma ammonia levels before and after TJO were 109 ± 62 and 67 ± 31 μg/dl, and the indocyanine green retention rates at 15 min were 31 ± 13 and 24 ± 13%, both showing a significant change (p < 0.01 and p < 0.05, respectively). Conclusions: We conclude that TJO increases portal blood flow which contributes to the decrease in plasma ammonia levels and the indocyanine green retention rate, although increasing the wedged hepatic venous pressure.


Digestive Surgery | 2000

Urgent Transjugular Retrograde Obliteration for Prophylaxis of Rebleeding from Gastric Varices in Patients with a Spontaneous Portosplenorenal Shunt

Fumio Chikamori; Nobutoshi Kuniyoshi; Susumu Shibuya; Yasuhiro Takase

Background: Bleeding isolated gastric varices with a spontaneous portosplenorenal shunt are difficult to control. The urgent use of transjugular retrograde obliteration (TJO) to prevent early rebleeding and to improve early mortality has not yet been demonstrated. We report our experience with this technique in patients with isolated gastric varices after treatment of acute bleeding. Methods: We reviewed our experience of 6 patients with isolated gastric varices with a spontaneous portosplenoral shunt treated with TJO after treatment of acute bleeding. We basically applied endoscopic glue embolization using cyanoacrylate monomer for treatment of acute bleeding. TJO was a method using an occlusive balloon catheter to control a spontaneous portosplenorenal shunt flow while injecting sclerosant retrograde into the gastric varices. Results: Treatment of acute bleeding was achieved immediately by endoscopic glue embolization, endoscopic variceal ligation, and ligating the varices with sutures following anterior gastrotomy in 4, 1 and 1 patients, respectively, and then TJO was performed. Permanent hemostasis and variceal eradication was achieved in these 6, and they all survived. They were alive for 6–66 months without gastric variceal recurrence. Conclusions: We conclude that urgent TJO is effective in the prophylaxis of early and late rebleeding from isolated gastric varices in patients with a spontaneous portosplenorenal shunt.


Surgery Today | 2002

Appendiceal stump abscess as an early complication of laparoscopic appendectomy: report of a case.

Fumio Chikamori; Nobutoshi Kuniyoshi; Susumu Shibuya; Yasuhiro Takase

Abstract.We report the case of an appendiceal stump abscess that was treated by relaparoscopy 4 days after a laparoscopic appendectomy (LA). Surgeons should be aware of the possibility of appendiceal stump abscess occurring as an early complication of LA. When performing LA, the appendiceal stump should be as short as possible, and the ligation of the root of the appendix should be only moderately tight, so as not to cause ischemic change of the stump, indicated by discoloration or edema. The insertion of a drain for monitoring exudate, as well as sonography, and relaparoscopy are helpful for diagnosing and treating this complication.


Digestive Surgery | 2000

Blood Supply Routes of Recurrent Esophageal Varices following Endoscopic Embolization

Fumio Chikamori; Sadao Nishio; Nobutoshi Kuniyoshi; Susumu Shibuya; Yasuhiro Takase

Background/Aim: The blood supply routes of recurrent esophageal varices following complete endoscopic embolization (EE) are not yet known. The purpose of this study is to identify these blood supply routes by comparing endoscopic varicography and percutaneous transhepatic portography (PTP). Methods: Eleven cases of recurrent esophageal varices following EE are included in this study. The blood supply routes of primary and recurrent varices were analyzed by comparing the varicography obtained at the initial and repeat EE with PTPs before and after the initial EE. Results: Endoscopic varicography at the time of initial EE could show the vessels of the left gastric vein (LGV) system, such as the cardiac branch of the LGV, and the cardiac venous plexus (CP) in 100% of cases, and the trunk of the LGV in 73% (8/11) of cases, whereas the posterior gastric vein was seen in only 18% (2/11) of cases. PTP performed 2 weeks after the initial EE confirmed that the routes visualized by endoscopic varicography could be obliterated in 10 of 11 cases. The blood supply routes of recurrent varices, demonstrated by varicography, were the vessels of the short gastric vein (SGV) system, such as the fundic branch of the SGV or the posterior gastric vein in 82% (9/11) of cases, and the partially reformed fine CP in 27% (3/11) of cases. Varicography revealed the remnant vessels of the LGV in only 1 case. Conclusions: The primary esophageal varices are supplied with blood mainly from the cardiac branch of the LGV through the CP. However, the blood supplies of recurrent varices following EE come from the fundic branch of the SGV or the posterior gastric vein. We conclude that three-dimensional obliteration of esophageal varices and their feeders, the LGV and SGV systems, is completed by initial and repeat EEs.


Digestive Surgery | 2000

Short-Term Portal Hemodynamic Effects of Endoscopic Embolization for Esophageal Varices

Fumio Chikamori; Nobutoshi Kuniyoshi; Susumu Shibuya; Yasuhiro Takase

Background/Aim: Endoscopic embolization (EE) is a specialized treatment that obliterates esophageal varices along with their associated blood supply. The purpose of this study was to investigate the short-term effects of EE for esophageal varices on portal hemodynamics and liver function. Methods: Thirty patients with esophageal varices were included in this study. The portal blood flow was measured by an ultrasonic duplex Doppler system before and after EE. EE was performed by freehand intravariceal injection of 5% ethanolamine oleate with iopamidol with the aid of a balloon attached to the tip of an endoscope under fluoroscopy. Results: For the blood supply system, endoscopic varicography at the time of EE was able to show the vessels of the cardiac branch of the left gastric vein in 93% of the cases, the cardiac venous plexus in 90%, the trunk of the left gastric vein in 27%, the lesser curvature branch of the left gastric vein in 10%, the fundic branch of the short gastric vein in 13%, and the posterior gastric vein in 13%. For the blood drainage system, endoscopic varicography was able to show the paraesophageal vein in 39% of the cases, the inferior phrenic vein in 17%, and the mediastinal vein in 13%. No clotting was detected after EE in the intra- and extraportal veins in any of the cases. The flow velocities in the main portal vein before and after EE were 14.2 ± 3.2 and 15.5 ± 3.5 cm/s, respectively, showing no significant change. The cross-sectional area of the portal vein before and after EE was 0.96 ± 0.21 and 1.04 ± 0.23 cm2, and the flow volume of the portal vein was 817 ± 288 and 930 ± 189 ml/min, both also showing no significant change. The blood laboratory parameters showed no significant change after EE. Conclusions: We conclude that neither portal blood flow nor liver function were damaged by EE, although both the varices and their associated blood supply were obliterated.


Surgery Today | 1985

Pathological studies on esophageal varices treated with injection sclerotherapy

Yasuhiro Takase; Masanori Kikuchi; Azusa Ozaki; Susumu Shibuya; Yoji Iwasaki

Injection sclerotherapy is one of the most effective treatments for esophageal varices. To investigate the fate of esophageal varices embolized with a sclerosant (ethanolamine oleate), we have examined at autopsy the esophageal wall of 14 patients with esophageal varices. When the sclerosant was injected into the varices, at first thrombi formed. After two weeks, granulation tissue appeared and the thrombi were gradually replaced. The granulation tissues were organized slowly after 3 months and in the organized granulation tissue, microscopic recanalization of vessels were seen in 8 out of 9 cases. There was no recurrence of the original varices andde novo varices occurred in one patient. These observations indicate that the varices embolized with ethanolamine oleate become organized in three months after the treatment, and accordingly the esophageal varices are cured. It became also clear that recurrence of the original varices did not occur after the organization.


Digestive Endoscopy | 2003

Huge submucosal hematoma of the stomach after accidental removal of the PErcutaneous endoscopic gastrostomy tube

Fumio Chikamori; Nobutoshi Kuniyoshi; Takahiko Kawashima; Yasuhiro Takase

We report a case of massive hemorrhage and aspiration pneumonia as complications of percutaneous endoscopic gastrostomy (PEG). Three months after insertion of a PEG tube, the patient accidentally pulled out the tube by himself. After the accident, the patient experienced hematemesis, which caused aspiration pneumonia. The button‐type tube was reinserted into the PEG fistula for hemostasis. The bleeding stopped temporarily; however, 21 days later, the patient relapsed into a condition of massive PEG site bleeding and hematemesis. He was transferred to our hospital, Kuniyoshi Hospital, to control the bleeding and aspiration pneumonia. Endoscopy revealed a sliding type of large hiatal hernia and a huge submucosal hematoma with an ulceration at the lower part of the gastric body. Emergency surgery including local gastrectomy, gastrostomy, jejunostomy and tracheostomy were helpful to treat these complications. Endoscopists should be aware how to treat these complications. One should not hesitate to perform open surgery when other treatments fail.


Digestive Endoscopy | 1995

Continuous Endoscopic Variceal Ligation with a Three‐shooter

Susumu Shibuya; Yasuhiro Takase; Fumio Chikamori; Akira Nakahara; Hisayuki Fukutomi

Endoscopic variceal ligation with an elastic O band has been performed in the treatment of esophageal varices. Generally, after ligating the varix during the treatment the endoscope is removed and the O band is changed each time until the desired result is achieved. However, it is thought that a shorter time to change the O band would make endoscopic variceal ligation more convenient. Therefore, we designed continuous endoscopic variceal ligation with three elastic O bands. To release three bands continuously, a self recoiling spring is attached at the endoscopic side between the inner and outer cylinders. After releasing one band by pulling the wire, the inner cylinder is returned to its original position by recoiling the spring and the next O band is automatically set up. Continuous endoscopic variceal ligation was performed for one case of esophageal varices due to hepatocellular carcinoma with liver cirrhosis. This technique enabled the ligation of three varices concomitantly, thus eliminating the necessity of repeated extraction and insertion of the endoscope every time the varix was ligated. The operation time was considerably shortened. The case reported did not develop any complications. Hence, it was thought that our technique of a three‐shooter is easier to perform and more convenient for the patient.

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