title: Self-expandable chitosan stent: design and preparation.
abstract: Stents are largely used in surgical procedures to relieve pathological obstructions. The purpose of the present study was to design and prepare a biocompatible stent with a self-expandable mechanism. Thin films were prepared from deacetylated chitosan (4% w/v) dissolved in acetic acid solution (2% v/v). The chitosan films were tested by a calibrated tensiometer to measure the Young's module (E). The films were used to manufacture stents by pulling and winding them around a cylindrical rod in a helical fashion. Thirteen stents (diameter = 0.5 +/- 0.05 mm, length approximately 4 mm) were inserted into the vas deferens of wistar rats. Upon stent insertion, the vasal anastomosis was achieved with a laser-soldering technique. The animals were sacrificied 8 weeks later. The stress test showed that the chitosan film was elastic (maximum strain = 105% +/- 6%, E = 0.7655 +/- 0.0288 Mpa). The stents self-expanded by releasing their elastic energy. All the stents but one remained open inside the vasa despite high incidence of sperm granuloma. A biocompatible and self-expandable stent with a helical design is proposed.
authors.affiliation: Center for Pediatric Urology and Minimal Invasive Urologic Surgery, Department of Urology, New York-Presbyterian Hospital-Weill Medical College of Cornell University, NY 10021, USA. a_lauto@hotmail.com
authors.forename: A
authors.initials: A
authors.lastname: Lauto
authors.forename: M
authors.initials: M
authors.lastname: Ohebshalom
authors.forename: M
authors.initials: M
authors.lastname: Esposito
authors.forename: J
authors.initials: J
authors.lastname: Mingin
authors.forename: P S
authors.initials: PS
authors.lastname: Li
authors.forename: D
authors.initials: D
authors.lastname: Felsen
authors.forename: M
authors.initials: M
authors.lastname: Goldstein
authors.forename: D P
authors.initials: DP
authors.lastname: Poppas
mesh_terms: D000818:Animals; D001672:Biocompatible Materials; D002686:Chitin / Q000031:analogs & derivatives; D048271:Chitosan; D004548:Elasticity; D004867:Equipment Design; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D015607:Stents
chemical_list: D001672:Biocompatible Materials; D002686:Chitin; D048271:Chitosan