Network


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

Hotspot


Dive into the research topics where Masaru Kubokawa is active.

Publication


Featured researches published by Masaru Kubokawa.


World Journal of Gastroenterology | 2012

Improved techniques for double-balloon-enteroscopy-assisted endoscopic retrograde cholangiopancreatography

Takashi Osoegawa; Yasuaki Motomura; Kazuya Akahoshi; Naomi Higuchi; Yoshimasa Tanaka; Terumasa Hisano; S. Itaba; Junya Gibo; Mariko Yamada; Masaru Kubokawa; Yorinobu Sumida; Hirotada Akiho; Eikichi Ihara; Kazuhiko Nakamura

AIM To investigate the clinical outcome of double balloon enteroscopy (DBE)-assisted endoscopic retrograde cholangiopancreatography (DB-ERCP) in patients with altered gastrointestinal anatomy. METHODS Between September 2006 and April 2011, 47 procedures of DB-ERCP were performed in 28 patients with a Roux-en-Y total gastrectomy (n = 11), Billroth II gastrectomy (n = 15), or Roux-en-Y anastomosis with hepaticojejunostomy (n = 2). DB-ERCP was performed using a short-type DBE combined with several technical innovations such as using an endoscope attachment, marking by submucosal tattooing, selectively applying contrast medium, and CO₂ insufflations. RESULTS The papilla of Vater or hepaticojejunostomy site was reached in its entirety with a 96% success rate (45/47 procedures). There were no significant differences in the success rate of reaching the blind end with a DBE among Roux-en-Y total gastrectomy (96%), Billroth II reconstruction (94%), or pancreatoduodenectomy (100%), respectively (P = 0.91). The total successful rate of cannulation and contrast enhancement of the target bile duct in patients whom the blind end was reached with a DBE was 40/45 procedures (89%). Again, there were no significant differences in the success rate of cannulation and contrast enhancement of the target bile duct with a DBE among Roux-en-Y total gastrectomy (88 %), Billroth II reconstruction (89%), or pancreatoduodenectomy (100%), respectively (P = 0.67). Treatment was achieved in all 40 procedures (100%) in patients whom the contrast enhancement of the bile duct was successful. Common endoscopic treatments were endoscopic biliary drainage (24 procedures) and extraction of stones (14 procedures). Biliary drainage was done by placement of plastic stents. Stones extraction was done by lithotomy with the mechanical lithotripter followed by extraction with a basket or by the balloon pull-through method. Endoscopic sphincterotomy was performed in 14 procedures with a needle precutting knife using a guidewire. The mean total duration of the procedure was 93.6 ± 6.8 min and the mean time required to reach the papilla was 30.5 ± 3.7 min. The mean time required to reach the papilla tended to be shorter in Billroth II reconstruction (20.9 ± 5.8 min) than that in Roux-en-Y total gastrectomy (37.1 ± 4.9 min) but there was no significant difference (P = 0.09). A major complication occurred in one patient (3.5%); perforation of the long limb in a patient with Billroth II anastomosis. CONCLUSION Short-type DBE combined with several technical innovations enabled us to perform ERCP in most patients with altered gastrointestinal anatomy.


Gastrointestinal Endoscopy | 2008

Endoscopic submucosal dissection by using a grasping-type scissors forceps: a preliminary clinical study (with video).

Kazuya Akahoshi; Kuniomi Honda; Hidefumi Akahane; Haruo Akiba; Noriaki Matsui; Yasuaki Motomura; Masaru Kubokawa; Shingo Endo; Naomi Higuchi; Masafumi Oya

BACKGROUND Endoscopic submucosal dissection (ESD) with a knife is a technically demanding procedure associated with a high complication rate. The shortcoming of this method is the difficulty of fixing the knife to the target lesion. It can lead to an unexpected incision and result in major complications, such as perforation and bleeding. To reduce the risk of complications related to ESD, we developed a new grasping-type scissors forceps (GSF), which can grasp and incise the targeted tissue by using electrosurgical current. OBJECTIVE To evaluate the efficacy and safety of ESD by using GSF for the removal of gastric neoplasms in human beings. DESIGN Prospective, uncontrolled, single center. SETTING Department of Gastroenterology, Aso Iizuka Hospital, Iizuka, Japan. PATIENTS Four patients with early gastric neoplastic lesions. INTERVENTIONS After marking and injection of a solution into the submucosa, the lesion was separated from the surrounding normal mucosa by complete incision around the lesion by using the GSF. A piece of submucosal tissue was grasped and cut with the GSF by using electrosurgical current to achieve submucosal excision. MAIN OUTCOME MEASUREMENT Technical success and complications. RESULTS All lesions were treated easily and safely, without any unexpected incisions. No delayed hemorrhage and perforation occurred. An en bloc resection and a negative resection margin was obtained in all cases. LIMITATIONS The small number of patients and an uncontrolled study. CONCLUSIONS ESD with GSF appeared to be an easy, safe, and technically efficient method for resecting GI neoplasms.


Digestion | 2012

A new approach: endoscopic submucosal dissection using the Clutch Cutter® for early stage digestive tract tumors.

Kazuya Akahoshi; Hidefumi Akahane; Yasuaki Motomura; Masaru Kubokawa; Syouichi Itaba; Keishi Komori; Naotaka Nakama; Masafumi Oya; Kazuhiko Nakamura

Endoscopic submucosal dissection (ESD) is accepted as minimally invasive therapy for early stage digestive tract tumors. It has allowed the achievement of histologically curative en-bloc resection of early stage digestive tract tumors regardless of size, including the resection of previously non-resectable tumors. Although numerous electrosurgical knives have been developed for ESD, technical difficulties and high complication rates (bleeding and perforation) have limited their use worldwide. Furthermore, conventional ESD usually needs several devices for each session. We developed the Clutch Cutter® (CC), which can grasp and incise the targeted tissue using electrosurgical current, to resolve such ESD-related problems. The ESD procedure using the CC is as follows: after marking using the CC and the injection of a solution into the submucosa, the lesion is separated from the surrounding normal mucosa by complete incision around the lesion using the CC. A piece of submucosal tissue is grasped and cut with the CC using electrosurgical current to achieve submucosal exfoliation. Intraoperative bleeding is also treated by the CC. Reported clinical studies showed that ESD using the CC is a safe, simple, easy-to-learn, technically efficient (en-bloc resection rate 100%), and a single-device method for the dissection of early stage digestive tract tumors. This new approach is promising to become the worldwide method of choice for early stage digestive tract tumors because it is technically simple and safe to perform.


Digestive Endoscopy | 2011

ENDOSCOPIC SUBMUCOSAL DISSECTION USING A GRASPING-TYPE SCISSORS FORCEPS FOR EARLY GASTRIC CANCERS AND ADENOMAS

Kazuya Akahoshi; Kuniomi Honda; Yasuaki Motomura; Masaru Kubokawa; Risa Okamoto; Takashi Osoegawa; Naotaka Nakama; Yumi Kashiwabara; Naomi Higuchi; Yoshimasa Tanaka; Masafumi Oya; Kazuhiko Nakamura

Aim:  To reduce the risk of complications related to endoscopic submucosal dissection (ESD) using knives, we developed a new grasping‐type scissors forceps (GSF) that can grasp and incise the target tissue using electrosurgical current. The aim of the present study was to evaluate the efficacy and safety of ESD using GSF for the removal of early gastric cancers and adenomas.


Journal of Clinical Gastroenterology | 2000

The beneficial effect of mesalazine on esophageal ulcers in intestinal Behcet's disease

Toshiyo Sonta; Yuzuru Araki; Masaru Kubokawa; Yasuhisa Tamura; Toshiaki Ochiai; Naohiko Harada; Yoshiharu Chijiiwa; Hajime Nawata

Intestinal Behcets disease in a 19-year-old girl was diagnosed because of the history of recurrent oral aphthous ulcers and typical endoscopic findings of esophageal and ileal ulcers. Her symptoms (e.g., dysphagia and retrosternal pain) were gradually relieved by treatment with prednisolone and total parenteral nutrition. However, about one month later, oral and esophageal ulcers appeared again. Mesalazine was added. Oral and esophageal ulcers healed promptly, and have not relapsed for about one year. Although mesalazine appears to act locally in the small intestine and colon, the therapeutic effect of mesalazine in this case may be explained by the systemic antiinflammatory effect. This case suggests that mesalazine is an effective drug and is a good candidate in the treatment of intestinal Behcets disease, especially accompanied with esophageal involvement.


Gut and Liver | 2012

Predictive factors for colonic diverticular rebleeding: a retrospective analysis of the clinical and colonoscopic features of 111 patients.

Yoshimasa Tanaka; Yasuaki Motomura; Kazuya Akahoshi; Risa Iwao; Keishi Komori; Naotaka Nakama; Takashi Osoegawa; Soichi Itaba; Masaru Kubokawa; Terumasa Hisano; Eikichi Ihara; Kazuhiko Nakamura; Ryoichi Takayanagi

Background/Aims Colonic diverticular bleeding can stop spontaneously or be stopped by endoscopic hemostasis. We analyzed the clinical and colonoscopic features of patients with colonic diverticular bleeding to establish the predictive factors for rebleeding. Methods A total of 111 patients (median age, 72 years) with colonic diverticular bleeding in Aso Iizuka Hospital between April 2007 and July 2010 were enrolled. Age, sex, body mass index (BMI), comorbidity, medication, location of bleeding, colonoscopic findings and hemostatic methods were analyzed retrospectively from the hospital records. Results The most common sites of bleeding were the ascending (39.6%) and sigmoid (29.7%) colon. Overt rebleeding occurred in 30 patients (27.0%). Spontaneous hemostasis was seen in 81 patients (73.0%), and endoscopic hemostatic treatment was performed in 30 patients. The BMI in the patients with colonic diverticular rebleeding was significantly higher than in patients without rebleeding. Colonoscopic findings of actively bleeding or nonbleeding visible vessels in the responsible diverticula were more frequent in the group with rebleeding. Conclusions A higher BMI and colonoscopic findings of actively bleeding or nonbleeding visible vessels can be used as predictive factors for colonic diverticular rebleeding. Patients with such findings should be carefully followed up after hemostasis of the initial colonic diverticular bleeding.


Endoscopy | 2010

Endoscopic submucosal dissection of early colorectal tumors using a grasping-type scissors forceps: a preliminary clinical study.

Kazuya Akahoshi; Okamoto R; Akahane H; Yasuaki Motomura; Masaru Kubokawa; T. Osoegawa; N. Nakama; T. Chaen; Masafumi Oya; Kazuhiko Nakamura

To reduce the risk of complications related to endoscopic submucosal dissection (ESD), we developed a new grasping-type scissors forceps (GSF), which can grasp and incise the targeted tissue using an electrosurgical current. We prospectively evaluated the efficacy and safety of ESD using GSF for the removal of colorectal tumors in 10 consecutive patients. After the submucosa had been injected with a solution, the lesion was separated from the surrounding normal mucosa by complete incision around the lesion using the GSF. A piece of submucosal tissue was grasped and cut with the GSF using an electrosurgical current to achieve submucosal excision. All lesions were treated easily and safely with no unexpected incisions. No delayed hemorrhage or perforation occurred. En bloc resection was obtained in all cases. The tumor-free lateral/basal margins were obtained in eight out of 10 patients. ESD using GSF appears to be an easy, safe, and technically efficient method for resecting early colorectal tumors.


Journal of Clinical Gastroenterology | 2008

Prospective comparative study on the acceptability of unsedated transnasal endoscopy in younger versus older patients

Atsuhiko Murata; Kazuya Akahoshi; Yasuaki Motomura; Noriaki Matsui; Masaru Kubokawa; Mitsuhide Kimura; Jiro Ouchi; Kuniomi Honda; Shingo Endo; Kazuhiko Nakamura; Ryoichi Takayanagi

Goals The aim of this prospective study was to compare the acceptance and tolerance for unsedated transnasal esophagogastroduodenoscopy (EGD) between younger and older patients. Background Little information is available on comparisons of younger and older patients with regard to acceptance and tolerance of transnasal EGD. Study A total of 260 patients were referred for unsedated transnasal EGD and divided into 2 groups according to their age: less than 60 years of age (group A, n=160) and 60 years of age and older (group B, n=100). A questionnaire for tolerance was completed by each patient (a validated 0 to 10 scale where “0” represents no discomfort/well tolerated and “10” represents severe discomfort/poorly tolerated). Results In 94.4% of group A and 95.0% of group B, insertions were successfully completed (P>0.05). Between groups A and B, discomfort during nasal anesthesia (1.7±0.2 vs. 1.6±0.2) and overall tolerance during procedure (1.7±0.2 vs. 1.5±0.2) were similar (P>0.05). However, discomfort during insertion was significantly greater in group A than in group B (2.5±0.2 vs. 1.9±0.2, P=0.02). Of all, 97.4% of group A and 94.7% of group B were willing to undergo unsedated transnasal EGD in the future (P>0.05). Conclusions There was no significant difference in acceptability between younger and older patients for unsedated transnasal EGD. Otherwise, younger patients experienced significantly more discomfort during insertion than did older patients.


Journal of Gastroenterology and Hepatology | 2013

Preserved gastric motility in patients with early gastric cancer after endoscopic submucosal dissection

Naomi Higuchi; Kazuhiko Nakamura; Eikichi Ihara; Kazuya Akahoshi; Hirotada Akiho; Yorinobu Sumida; Yasuaki Motomura; Masaru Kubokawa; Tetsuhide Ito; Ryoichi Takayanagi

Endoscopic submucosal dissection (ESD) is now accepted as a minimally invasive treatment for early gastric cancer (EGC). To our knowledge, however, the functional effects of ESD have not been determined in patients with EGC. We therefore investigated whether gastric motility was affected by ESD.


Endoscopy | 2013

Endoscopic submucosal dissection using the "Clutch Cutter" for early esophageal squamous cell carcinoma.

Kazuya Akahoshi; Yousuke Minoda; Keishi Komori; Yasuaki Motomura; Masaru Kubokawa; Yoshihiro Otsuka; Syouhei Hamada; Shinichirou Fukuda; Risa Iwao; Junya Gibo; Masafumi Oya; Kazuhiko Nakamura

BACKGROUND AND STUDY AIMS To reduce the risk of complications related to the use of knives in endoscopic submucosal dissection (ESD), we developed the Clutch Cutter which can grasp and incise targeted tissue using electrosurgical current, similarly to a biopsy technique. The study aim was to evaluate the efficacy and safety of ESD using the Clutch Cutter for early esophageal squamous cell carcinoma. PATIENTS AND METHODS ESD using the Clutch Cutter was performed on 32 consecutive patients with early esophageal squamous cell carcinoma. Therapeutic efficacy and safety were assessed. RESULTS All lesions were treated easily and safely without unintended incision. En bloc resection was obtained in all patients. Histologically negative margins were obtained in 26/32 patients (81%). Endoscopic perforation due to the hood in one patient (3%), mediastinitis without endoscopic perforation in one patient (3%), and post-ESD stricture in 5 patients (16%) were observed. All were successfully managed conservatively. CONCLUSIONS ESD using the Clutch Cutter appears to be a safe, easy, and technically efficient method for resecting early esophageal squamous cell carcinomas.

Collaboration


Dive into the Masaru Kubokawa'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
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge