The Experts below are selected from a list of 2859 Experts worldwide ranked by ideXlab platform
Hironori Yamamoto - One of the best experts on this subject based on the ideXlab platform.
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endoscopic submucosal dissection using Sodium Hyaluronate for large superficial tumors in the colon
2004Co-Authors: Hironori Yamamoto, Yutaka Sekine, Keijiro Sunada, Tomohiko Miyata, Tomonori Yano, Hiroto Kita, Michiko Iwamoto, Nobuki Onishi, Akiko Kuno, Kenichi IdoAbstract:Endoscopic submucosal dissection is becoming popular for large superficial gastric cancer in Japan. However, it is considered difficult in the colon because the colonic wall is much thinner than the gastric wall. We use several devices to overcome this difficulty and have made it feasible in the colon as well. Submucosal injection of Sodium Hyaluronate is used to maintain sufficient thickening of the submucosal tissue and a small-caliber-tip or regular cylindrical transparent hood is used to open up the incised mucosa as a substitute for countertraction. In this method, not only the lateral margin, but the vertical margin of the resection can also be determined precisely because submucosal incision is carried out under direct visualization of the submucosal tissue.
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successful en bloc resection of large superficial tumors in the stomach and colon using Sodium Hyaluronate and small caliber tip transparent hood
2003Co-Authors: Hironori Yamamoto, Yutaka Sekine, Hiroshi Kawata, Keijiro Sunada, A Sasaki, Katsuyuki Nakazawa, Tomohiko Miyata, Tomonori Yano, K Satoh, Kenichi IdoAbstract:En-bloc resection is desirable for accurate histopathological assessment of tissue specimens obtained using endoscopic mucosal resection (EMR). A new EMR method using Sodium Hyaluronate and a small-caliber-tip transparent hood has been developed. This is a peeling-off method using a needle-knife for mucosal and submucosal incisions. Long-lasting submucosal thickening resulting from an injection of Sodium Hyaluronate, and good visualization of the submucosal tissue with the aid of a small-caliber-tip transparent hood, make the cutting procedures easy and safe. A large superficial gastric cancer and a large villous tumor of the sigmoid colon were endoscopically resected using this method. En-bloc endoscopic resection was successful in both patients. The gastric lesion was an well-differentiated intramucosal adenocarcinoma, completely resected in a specimen measuring 97 x 50 mm. The colonic lesion was an intramucosal well-differentiated adenocarcinoma in adenoma, completely resected in a specimen measuring 70 x 55 mm in diameter. No significant complications were noted in either patient. The new method of EMR using Sodium Hyaluronate and the small-caliber-tip transparent hood is a promising method for endoscopic en-bloc resection of large superficial neoplastic lesions, both in the stomach and the colon.
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success rate of curative endoscopic mucosal resection with circumferential mucosal incision assisted by submucosal injection of Sodium Hyaluronate
2002Co-Authors: Hironori Yamamoto, Hiroshi Kawata, Keijiro Sunada, Kiichi Satoh, Yoshinari Kaneko, Kentaro SuganoAbstract:Background: Circumferential mucosal incision around a lesion is effective for reliable endoscopic mucosal resection. However, mucosal incision with a needle knife is difficult, even with submucosal injection of normal saline solution. To make needle-knife incision easier and safer, Sodium Hyaluronate has been used rather than normal saline solution. The aim of this study was to evaluate the clinical outcome of endoscopic mucosal resection with circumferential mucosal incision assisted by submucosal injection of Sodium Hyaluronate. Methods: For 70 gastric lesions treated by submucosal injection of Sodium Hyaluronate, the size of the lesion and the resection specimen, the en bloc resection rate, complications, and local recurrence during follow-up were assessed. Results: The mean size of the lesions and resection specimens were, respectively, 19.9 mm and 30.0 mm. The en bloc resection rates were 89% (42/47) for lesions up to 20 mm in diameter and 48% (11/23) for those greater than 20 mm (1-20 mm vs. >20 mm, p = 0.0004). Three patients underwent surgery because of invasive cancer in the EMR specimen. During follow-up (median 14 months, range 3-38 months), 2 recurrent lesions were found. No major complication occurred. Conclusions: Submucosal injection of Sodium Hyaluronate is a reliable method with a high success rate for en bloc resection of lesions up to 20 mm in diameter. Mucosal incision with a needle knife can be performed safely with submucosal injection of Sodium Hyaluronate. (Gastrointest Endosc 2002;56:507-12.)
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successful en bloc resection of a large superficial gastric cancer by using Sodium Hyaluronate and electrocautery incision forceps
2001Co-Authors: Hironori Yamamoto, Yutaka Sekine, Toshihiko Higashizawa, Yoshinari Kaneko, K Kihira, Yoshinori Hosoya, Ken Saito, Kentaro SuganoAbstract:Background: The advisability of endoscopic mucosal resection (EMR) for treatment of large superficial gastric cancers has been challenged. For more reliable en bloc resection, a new method of EMR was developed that uses a viscous substance, Sodium Hyaluronate, and two newly designed devices. Methods: A large superficial gastric cancer was treated with this new EMR technique. Sodium Hyaluronate was injected into the submucosa and mucosal incisions were made with a needle-knife. The newly developed incision forceps and flat-ended transparent hood were used for submucosal incisions. Results: The large cancer was successfully resected endoscopically as a single piece of mucosa 6 cm in diameter without complication. Histopathologic evaluation of the specimen confirmed that the resection was curative. Conclusions: EMR with Sodium Hyaluronate along with two new devices may be a reliable method for en bloc resection of large superficial gastric lesions.
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a novel method of endoscopic mucosal resection using Sodium Hyaluronate
1999Co-Authors: Hironori Yamamoto, Tomizo Yube, Norio Isoda, Yutaka Sekine, Ken Kimura, Toshihiko Higashizawa, Yukihiro Sato, Nobuyuki KanaiAbstract:Abstract Background: Saline-assisted endoscopic mucosal resection is an established therapeutic method. However, it is sometimes difficult to maintain a desired level of tissue elevation after injection of saline. Therefore we decided to use a mucinous substance such as Sodium Hyaluronate instead of saline. Methods: Two resected porcine stomachs and five dogs were used for the study. The elevations, made by submucosal injections of Sodium Hyaluronate, were compared with those produced with normal saline. Sodium Hyaluronate–assisted mucosal resections were compared with the saline-assisted resections. Results: Mucosal elevations created by submucosal injections of Sodium Hyaluronate remained for a longer time with a clearer margin compared to those made by saline injection. Endoscopic mucosal resections were performed safely with the assistance of Sodium Hyaluronate. Conclusions: Use of Sodium Hyaluronate instead of saline for endoscopic mucosal resection could make the procedure easier and more reliable.
Kentaro Sugano - One of the best experts on this subject based on the ideXlab platform.
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success rate of curative endoscopic mucosal resection with circumferential mucosal incision assisted by submucosal injection of Sodium Hyaluronate
2002Co-Authors: Hironori Yamamoto, Hiroshi Kawata, Keijiro Sunada, Kiichi Satoh, Yoshinari Kaneko, Kentaro SuganoAbstract:Background: Circumferential mucosal incision around a lesion is effective for reliable endoscopic mucosal resection. However, mucosal incision with a needle knife is difficult, even with submucosal injection of normal saline solution. To make needle-knife incision easier and safer, Sodium Hyaluronate has been used rather than normal saline solution. The aim of this study was to evaluate the clinical outcome of endoscopic mucosal resection with circumferential mucosal incision assisted by submucosal injection of Sodium Hyaluronate. Methods: For 70 gastric lesions treated by submucosal injection of Sodium Hyaluronate, the size of the lesion and the resection specimen, the en bloc resection rate, complications, and local recurrence during follow-up were assessed. Results: The mean size of the lesions and resection specimens were, respectively, 19.9 mm and 30.0 mm. The en bloc resection rates were 89% (42/47) for lesions up to 20 mm in diameter and 48% (11/23) for those greater than 20 mm (1-20 mm vs. >20 mm, p = 0.0004). Three patients underwent surgery because of invasive cancer in the EMR specimen. During follow-up (median 14 months, range 3-38 months), 2 recurrent lesions were found. No major complication occurred. Conclusions: Submucosal injection of Sodium Hyaluronate is a reliable method with a high success rate for en bloc resection of lesions up to 20 mm in diameter. Mucosal incision with a needle knife can be performed safely with submucosal injection of Sodium Hyaluronate. (Gastrointest Endosc 2002;56:507-12.)
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successful en bloc resection of a large superficial gastric cancer by using Sodium Hyaluronate and electrocautery incision forceps
2001Co-Authors: Hironori Yamamoto, Yutaka Sekine, Toshihiko Higashizawa, Yoshinari Kaneko, K Kihira, Yoshinori Hosoya, Ken Saito, Kentaro SuganoAbstract:Background: The advisability of endoscopic mucosal resection (EMR) for treatment of large superficial gastric cancers has been challenged. For more reliable en bloc resection, a new method of EMR was developed that uses a viscous substance, Sodium Hyaluronate, and two newly designed devices. Methods: A large superficial gastric cancer was treated with this new EMR technique. Sodium Hyaluronate was injected into the submucosa and mucosal incisions were made with a needle-knife. The newly developed incision forceps and flat-ended transparent hood were used for submucosal incisions. Results: The large cancer was successfully resected endoscopically as a single piece of mucosa 6 cm in diameter without complication. Histopathologic evaluation of the specimen confirmed that the resection was curative. Conclusions: EMR with Sodium Hyaluronate along with two new devices may be a reliable method for en bloc resection of large superficial gastric lesions.
Yutaka Sekine - One of the best experts on this subject based on the ideXlab platform.
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endoscopic submucosal dissection using Sodium Hyaluronate for large superficial tumors in the colon
2004Co-Authors: Hironori Yamamoto, Yutaka Sekine, Keijiro Sunada, Tomohiko Miyata, Tomonori Yano, Hiroto Kita, Michiko Iwamoto, Nobuki Onishi, Akiko Kuno, Kenichi IdoAbstract:Endoscopic submucosal dissection is becoming popular for large superficial gastric cancer in Japan. However, it is considered difficult in the colon because the colonic wall is much thinner than the gastric wall. We use several devices to overcome this difficulty and have made it feasible in the colon as well. Submucosal injection of Sodium Hyaluronate is used to maintain sufficient thickening of the submucosal tissue and a small-caliber-tip or regular cylindrical transparent hood is used to open up the incised mucosa as a substitute for countertraction. In this method, not only the lateral margin, but the vertical margin of the resection can also be determined precisely because submucosal incision is carried out under direct visualization of the submucosal tissue.
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successful en bloc resection of large superficial tumors in the stomach and colon using Sodium Hyaluronate and small caliber tip transparent hood
2003Co-Authors: Hironori Yamamoto, Yutaka Sekine, Hiroshi Kawata, Keijiro Sunada, A Sasaki, Katsuyuki Nakazawa, Tomohiko Miyata, Tomonori Yano, K Satoh, Kenichi IdoAbstract:En-bloc resection is desirable for accurate histopathological assessment of tissue specimens obtained using endoscopic mucosal resection (EMR). A new EMR method using Sodium Hyaluronate and a small-caliber-tip transparent hood has been developed. This is a peeling-off method using a needle-knife for mucosal and submucosal incisions. Long-lasting submucosal thickening resulting from an injection of Sodium Hyaluronate, and good visualization of the submucosal tissue with the aid of a small-caliber-tip transparent hood, make the cutting procedures easy and safe. A large superficial gastric cancer and a large villous tumor of the sigmoid colon were endoscopically resected using this method. En-bloc endoscopic resection was successful in both patients. The gastric lesion was an well-differentiated intramucosal adenocarcinoma, completely resected in a specimen measuring 97 x 50 mm. The colonic lesion was an intramucosal well-differentiated adenocarcinoma in adenoma, completely resected in a specimen measuring 70 x 55 mm in diameter. No significant complications were noted in either patient. The new method of EMR using Sodium Hyaluronate and the small-caliber-tip transparent hood is a promising method for endoscopic en-bloc resection of large superficial neoplastic lesions, both in the stomach and the colon.
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successful en bloc resection of a large superficial gastric cancer by using Sodium Hyaluronate and electrocautery incision forceps
2001Co-Authors: Hironori Yamamoto, Yutaka Sekine, Toshihiko Higashizawa, Yoshinari Kaneko, K Kihira, Yoshinori Hosoya, Ken Saito, Kentaro SuganoAbstract:Background: The advisability of endoscopic mucosal resection (EMR) for treatment of large superficial gastric cancers has been challenged. For more reliable en bloc resection, a new method of EMR was developed that uses a viscous substance, Sodium Hyaluronate, and two newly designed devices. Methods: A large superficial gastric cancer was treated with this new EMR technique. Sodium Hyaluronate was injected into the submucosa and mucosal incisions were made with a needle-knife. The newly developed incision forceps and flat-ended transparent hood were used for submucosal incisions. Results: The large cancer was successfully resected endoscopically as a single piece of mucosa 6 cm in diameter without complication. Histopathologic evaluation of the specimen confirmed that the resection was curative. Conclusions: EMR with Sodium Hyaluronate along with two new devices may be a reliable method for en bloc resection of large superficial gastric lesions.
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a novel method of endoscopic mucosal resection using Sodium Hyaluronate
1999Co-Authors: Hironori Yamamoto, Tomizo Yube, Norio Isoda, Yutaka Sekine, Ken Kimura, Toshihiko Higashizawa, Yukihiro Sato, Nobuyuki KanaiAbstract:Abstract Background: Saline-assisted endoscopic mucosal resection is an established therapeutic method. However, it is sometimes difficult to maintain a desired level of tissue elevation after injection of saline. Therefore we decided to use a mucinous substance such as Sodium Hyaluronate instead of saline. Methods: Two resected porcine stomachs and five dogs were used for the study. The elevations, made by submucosal injections of Sodium Hyaluronate, were compared with those produced with normal saline. Sodium Hyaluronate–assisted mucosal resections were compared with the saline-assisted resections. Results: Mucosal elevations created by submucosal injections of Sodium Hyaluronate remained for a longer time with a clearer margin compared to those made by saline injection. Endoscopic mucosal resections were performed safely with the assistance of Sodium Hyaluronate. Conclusions: Use of Sodium Hyaluronate instead of saline for endoscopic mucosal resection could make the procedure easier and more reliable.
Michael Rubinstein - One of the best experts on this subject based on the ideXlab platform.
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elastic plastic transformation of polyelectrolyte complex hydrogels from chitosan and Sodium Hyaluronate
2018Co-Authors: Ran Shi, Tao Lin Sun, Feng Luo, Tasuku Nakajima, Takayuki Kurokawa, Yue Zhen Bin, Michael RubinsteinAbstract:Hydrogels formed by polyelectrolyte complexation (PEC) of oppositely charged biopolymers, free of any chemical additives, are promising biomaterials. In this work, the mechanical behavior of hydrogels consisting of positively charged chitosan and negatively charged Sodium Hyaluronate (HA) at balanced charge composition is investigated. These hydrogels exhibit strong tensile strain and strain rate dependence. They are elastic-like, independent of the strain rate at small strain, but exhibit plastic-like behavior above the yield point by showing a monotonous decrease of the stress. The cyclic tensile test demonstrates that these hydrogels exhibit small and quickly recoverable hysteresis in the elastic-like region but large and partially recoverable hysteresis above the yield point. The stress relaxation experiment shows a plateau in the reduced stress followed by an abrupt fracture, and the time to failure decreases exponentially with increasing applied step strain. Such elastic-to-plastic-like transformati...
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Elastic–Plastic Transformation of Polyelectrolyte Complex Hydrogels from Chitosan and Sodium Hyaluronate
2018Co-Authors: Ran Shi, Tao Lin Sun, Feng Luo, Tasuku Nakajima, Takayuki Kurokawa, Yue Zhen Bin, Michael Rubinstein, Jian Ping GongAbstract:Hydrogels formed by polyelectrolyte complexation (PEC) of oppositely charged biopolymers, free of any chemical additives, are promising biomaterials. In this work, the mechanical behavior of hydrogels consisting of positively charged chitosan and negatively charged Sodium Hyaluronate (HA) at balanced charge composition is investigated. These hydrogels exhibit strong tensile strain and strain rate dependence. They are elastic-like, independent of the strain rate at small strain, but exhibit plastic-like behavior above the yield point by showing a monotonous decrease of the stress. The cyclic tensile test demonstrates that these hydrogels exhibit small and quickly recoverable hysteresis in the elastic-like region but large and partially recoverable hysteresis above the yield point. The stress relaxation experiment shows a plateau in the reduced stress followed by an abrupt fracture, and the time to failure decreases exponentially with increasing applied step strain. Such elastic-to-plastic-like transformation of the biopolymer PEC gels is quite different from the behaviors of PEC hydrogels formed by oppositely charged vinyl-type synthetic polyelectrolytes due to the difference in flexibility, charge density, and ionic bond strength of these polymers
Michael Larsen - One of the best experts on this subject based on the ideXlab platform.
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long term results of extracapsular cataract extraction with posterior chamber lens implantation Sodium Hyaluronate 1 vs hydroxypropyl methylcellulose 2
2009Co-Authors: Allan Storrpaulsen, Michael LarsenAbstract:We investigated the frequency of surgical complications and the long-term outcome in terms of visual acuity, intraocular pressure and post-operative complications in 206 extracapsular cataract extraction procedures with posterior chamber lens implantation using either Sodium Hyaluronate 1% (Healon) or hydroxypropyl-methylcellulose 2% over a follow-up period of 12 months. We found no significant difference in the results of using either of the two viscoelastic agents.
