Biliary strictures or bile duct strictures are said to be an irregular tapering of the general bile duct, the tube that shifts bile i.e. a substance that aids in digestion from the liver to the small intestine.
Boston Scientific Corporation announced that it has been given 510(k) authorization from the U.S. Food and Drug Administration (FDA) to promote its WallFlex Biliary RX fully and partially covered stents for the palliative treatment of malignant bile duct strictures. The WallFlex Biliary RX uncovered stent was approved by the FDA in 2006.
All three models of the WallFlex Biliary RX Stenting System i.e. fully covered, partially covered and uncovered may now be acquired in both the United States and Europe.
Kenneth F. Binmoeller, M.D., Director of Interventional Endoscopy at California Pacific Medical Center, and an investigator for the WallFlex Biliary RX fully covered stent study, commented, “The WallFlex Biliary RX Stent System represents the next stage in self-expandable metal stent technology. The stent has greater flexibility to aid with placement in tortuous anatomies and new features such as flared ends that may reduce the risk of migration.”
The WallFlex Biliary RX Stent is designed to provide the advantages of prior-generation stents like the industry-leading WALLSTENT Endoprosthesis, while including latest features to accommodate a variety of anatomical and clinical necessities. Based on wide investigation and physician feedback, the WallFlex Biliary RX Stent apparently utilizes a platinum-cored Nitinol construction designed to carry three significant components: radial force, flexibility and radiopacity.
The Platinol Wire supposedly offers better flexibility i.e. about 30 percent more as compared to WALLSTENT Endoprosthesis, to apparently assist the stent conform in tortuous anatomies. The improved full-length radiopacity provided by the Platinol Wire and the reconstrainable delivery system are said to be designed to permit for more accurate stent position, while the radial force of the WallFlex Biliary RX Stent is believed to be designed to preserve patency and resist relocation.
TheWallFlex Biliary RX Stents also has a closed-cell construction apparently intended to defend against tissue ingrowth, looped ends designed to decrease the threat of tissue trauma, and flared ends to aid in decreasing the danger of stent migration. The proprietary, durable silastic polymer covering of the fully and partially covered stents is planned in such a way so as to diminish the possibility for tumor ingrowth. Moreover, the WallFlex Biliary RX Stent apparently includes an incorporated retrieval loop for removal during the preliminary stent placement process, which could be used in the occasion of incorrect placement.
Michael Phalen, President, Boston Scientific Endoscopy, mentioned, “Boston Scientific continues to fulfill our promise to deliver industry-leading, innovative technologies that enable physicians to best diagnose and treat digestive diseases, and enhance quality of life for patients. The WallFlex Biliary RX Stent leverages existing Boston Scientific technologies, while advancing performance with new features such as a unique Platinol Wire construction. We believe we are truly delivering the next generation of stents for the treatment of malignant bile duct strictures.”
The initial outcomes from Dr. Petersen’s study were accounted at United European Gastroenterology Week (UEGW) in 2008. The results illustrated that the fully covered WallFlex Biliary RX Stent apparently had technically successful placement, low rates of re-intervention and repeated biliary impediments, and negligible incidence of migration and complications.
With around 98 percent of patients gathering at the principal endpoint of clinical palliation of the biliary obstruction until completion of follow-up, study results claims that the fully covered WallFlex Biliary RX Stent may effectively palliate majority of the patients with malignant distal biliary obstructions.
In the UEGW, initial data on a 70-patient WallFlex Biliary RX partially covered stent study was also presented. This study was headed by Primary Investigator Guido Costamagna, M.D., Head of Digestive Endoscopy at Universita Cattolica del Sacro Cuore in Rome. Initial outcomes of the study show that the partially covered metal stent may palliate majority of the patients with malignant biliary obstructions.
Pancreatic cancer is thought to be the most common cause of malignant biliary obstructions. Around 250,000 new cases are detected worldwide every year. Nearly all patients have less than six months to survive post diagnosis. Other causes of malignant biliary obstructions comprise of bile duct, liver and gallbladder cancer.
Around 70 percent of patients suffering form malignant bile duct obstruction are poor contenders for surgery as the cancer has spread. With these cases, palliative treatment could enhance the patient’s quality of life by regulating the symptoms and complications of the disease.
The security and efficacy of the WallFlex Biliary RX Stenting System for use in the vascular system have apparently not been established.