title: Different outcomes in urethral reconstruction using elastin and collagen patches and conduits in rabbits.
abstract: OBJECTIVE
  To study the feasibility of urethral reconstruction with two urethroplasty techniques using an elastin and collagen heterograft in rabbits.
  
  
  METHODS
  Fifty-two male rabbits were studied. Two types of injury, (1) a 1.5 x 0.6 cm2 semicircumferential defect; (2) a 1.5 cm segmental defect of the penile urethra, were created and repaired using size-matched elastin and collagen patches or tubed conduits. Urethral repair by primary closure for the type 1 injury and a tubularized autologous bladder mucosal graft for the type 2 injury served as controls. At 3 months, urethral diameter was measured with retrograde urethrography. The animals were then euthanized for histological examination.
  
  
  RESULTS
  The postoperative complication rate was significantly higher in the urethral reconstructions using tubed collagen (83%) and elastin (50%) grafts compared to the patch onlay grafts (p = 0.001 for collagen and p = 0.01 for elastin) and tubularized ABM (10%, p = 0.003 and 0.05, respectively). At the type 2 injury site, a dense circumferential fibrosis developed after all repairs. Only minimal ventral fibrosis presented in the type 1 injury repair. The intensity of chronic inflammation and fibrosis was greatest when collagen was used for the urethral repair. In the elastin urethral repairs the urethral diameter decreased significantly for the tubed repair compared to the patch onlay (p = 0.02).
  
  
  CONCLUSIONS
  Urethral injury repair using elastin and collagen biomaterials is feasible in the rabbit model. The results of onlay urethroplasty using the elastin and collagen patches are significantly superior to those using the elastin and collagen tubed conduits.
authors.affiliation: Oregon Medical Laser Center, Providence St. Vincent Medical Center, 9205 SW Barnes Road, Portland, Oregon 97225, USA. hua.xie@providence.org
authors.forename: Hua
authors.initials: H
authors.lastname: Xie
authors.forename: Carmen E
authors.initials: CE
authors.lastname: Campbell
authors.forename: Brian S
authors.initials: BS
authors.lastname: Shaffer
authors.forename: Kenton W
authors.initials: KW
authors.lastname: Gregory
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000008:administration & dosage* / Q000737:chemistry; D003094:Collagen / Q000008:administration & dosage* / Q000737:chemistry; D004549:Elastin / Q000008:administration & dosage* / Q000737:chemistry; D005355:Fibrosis; D008297:Male; D011183:Postoperative Complications / Q000473:pathology / Q000517:prevention & control*; D011817:Rabbits; D019651:Plastic Surgery Procedures; D014521:Urethra / Q000473:pathology / Q000601:surgery; D014522:Urethral Diseases / Q000473:pathology / Q000601:surgery*; D013520:Urologic Surgical Procedures
chemical_list: D001672:Biocompatible Materials; D003094:Collagen; D004549:Elastin