title: The Stent Patency and Migration Rate of Different Shaped Plastic Stents in Bile Flow Phantom Model and In Vivo Animal Bile Duct Dilation Model.
abstract: In research and development of biliary plastic stents (PS), continuous efforts have been made to overcome short patency time and high rate of migration. The aim of this study was to evaluate the patency and migration rate of different PS shapes for a given period of time.
  
  
  
  Using an in vitro bile phantom model, we compared the patency among different shapes of PS (three straight PS, four double-pigtail PS, and a new screw-shaped PS). We performed an analysis of the degree of luminal narrowing by light microscopic examination. Using an in vivo swine model, we compared the patency and migration rate among the three different types of PS.
  
  
  
  Eight weeks after the bile exposure in the bile flow phantom model, 80 PS were retrieved and analyzed. The straight PS showed less biofilm formation and luminal narrowing than other types of PS (p < 0.05). Forty-nine PS were inserted into the dilated bile ducts of 10 swine models, and 39 PS were successfully retrieved 8 weeks later. The stent migration occurred less frequently in the double-pigtail PS and the screw-shaped PS than it did in the straight PS (11.1, 10, and 27.3%, respectively). However, there was no statistical difference in stent patency among the different shapes.
  
  
  
  Stent patency may not be significantly different depending on the shape of PS for 8 weeks. The screw-shaped PS showed similar patency and migration rate to the double-pigtail PS. These results may help guiding future PS development and clinical decisions.
authors.affiliation: Digestive Disease Center, CHA Bundang Medical Center, CHA University, Seongnam, Republic of Korea.
authors.forename: Chang-Il
authors.initials: CI
authors.lastname: Kwon
authors.affiliation: Department of Pathology, CHA Bundang Medical Center, CHA University, Seongnam, Republic of Korea.
authors.forename: Gwangil
authors.initials: G
authors.lastname: Kim
authors.affiliation: Digestive Disease Center, Department of Internal Medicine, Inha University Hospital, Inha University School of Medicine, 27 Inhang-ro, Jung-gu, Incheon, 400-711, Republic of Korea. inos@inha.ac.kr.
authors.forename: Seok
authors.initials: S
authors.lastname: Jeong
authors.affiliation: Digestive Disease Center, Department of Internal Medicine, Inha University Hospital, Inha University School of Medicine, 27 Inhang-ro, Jung-gu, Incheon, 400-711, Republic of Korea.
authors.forename: Don Haeng
authors.initials: DH
authors.lastname: Lee
authors.affiliation: Digestive Disease Center, CHA Bundang Medical Center, CHA University, Seongnam, Republic of Korea.
authors.forename: Kyoung Ah
authors.initials: KA
authors.lastname: Kim
authors.affiliation: Digestive Disease Center, CHA Bundang Medical Center, CHA University, Seongnam, Republic of Korea.
authors.forename: Kwang Hyun
authors.initials: KH
authors.lastname: Ko
authors.affiliation: Digestive Disease Center, CHA Bundang Medical Center, CHA University, Seongnam, Republic of Korea.
authors.forename: Joo Young
authors.initials: JY
authors.lastname: Cho
authors.affiliation: Digestive Disease Center, CHA Bundang Medical Center, CHA University, Seongnam, Republic of Korea.
authors.forename: Sung Pyo
authors.initials: SP
authors.lastname: Hong
mesh_terms: D000818:Animals; D001652:Bile Ducts / Q000601:surgery*; D004106:Dilatation / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D023421:Models, Animal; D019047:Phantoms, Imaging; D010969:Plastics; D015607:Stents; D013552:Swine
chemical_list: D010969:Plastics
keywords: Biliary stents; Plastic stents; Stent migration; Stent patency