title: Physiologic properties of small intestine submucosa.
abstract: BACKGROUND
  Porcine small intestine submucosa (SiS) has been introduced as a bioprosthesis in herniorrhaphy. This study evaluates in vivo properties of SiS that would affect clinical use.
  
  
  METHODS
  Twelve pigs underwent implantation of SiS (perforated and nonperforated) on the peritoneal surface. Gross characteristics were evaluated and random samples harvested for histological study at 2 (n = 6) and 8 (n = 6) weeks. Collagen deposition was determined by polarized microscopy. Neovascularity (percent area blood vessels, %A(bv)) was determined by immunohistochemical staining with a polyclonal CD-31 antibody.
  
  
  RESULTS
  Perforated SiS had a higher density of capillary ingrowth compared with nonperforated at both 2 (5.6%A(bv) versus 1.4%A(bv), P < 0.05) and 8 weeks (6.0%A(bv) versus 1.6%A(bv), P < 0.05). Compared with 2 weeks, 8-week SiS had a larger proportion of incorporation (25% versus 83%, P < 0.05) and new collagen deposition (50% versus 94%, P < 0.05). Significant contraction was observed in SiS 8 weeks after implantation (preimplant area 98 cm2 versus post-implant area 50 cm2, P < 0.05).
  
  
  CONCLUSIONS
  SiS incorporated well 8 weeks after implantation, with deposition of new collagen. Perforated SiS demonstrated a more rapid and greater amount of neovascularity. The degree of contraction suggests that larger areas of SiS should be selected for herniorrhaphy than would be necessary if synthetic materials were used.
authors.affiliation: Division of General Surgery, Section of Surgical Sciences, Vanderbilt University School of Medicine, Nashville, Tennessee, USA. benjamin.poulose@vanderbilt.edu
authors.forename: Benjamin K
authors.initials: BK
authors.lastname: Poulose
authors.forename: Stefan
authors.initials: S
authors.lastname: Scholz
authors.forename: Derek E
authors.initials: DE
authors.lastname: Moore
authors.forename: Carl R
authors.initials: CR
authors.lastname: Schmidt
authors.forename: Eric L
authors.initials: EL
authors.lastname: Grogan
authors.forename: Oliver B
authors.initials: OB
authors.lastname: Lao
authors.forename: Lillian
authors.initials: L
authors.lastname: Nanney
authors.forename: Jeff
authors.initials: J
authors.lastname: Davidson
authors.forename: Michael D
authors.initials: MD
authors.lastname: Holzman
mesh_terms: D020341:Absorbable Implants; D000818:Animals; D002196:Capillaries / Q000502:physiology; D003094:Collagen / Q000378:metabolism; D005260:Female; D006085:Graft Survival; D007413:Intestinal Mucosa / Q000098:blood supply / Q000502:physiology* / Q000637:transplantation*; D007421:Intestine, Small / Q000098:blood supply / Q000502:physiology* / Q000637:transplantation*; D018919:Neovascularization, Physiologic; D013552:Swine; D023822:Tissue Engineering
chemical_list: D003094:Collagen