title: Vascular anatomy of the small intestine-a comparative anatomic study on humans and pigs.
abstract: BACKGROUND
  Porcine models are well established for studying intestinal anastomotic healing. In this study, we aimed to clarify the anatomic differences between human and porcine small intestines. Additionally, we investigated the influences of longitudinal and circular sutures on human small intestine perfusion.
  
  
  METHODS
  Intestines were obtained from human cadavers (n = 8; small intestine, n = 51) and from pigs (n = 10; small intestine, n = 60). Vascularization was visualized with mennige gelatin perfusion and high-resolution mammography. Endothelial cell density was analyzed with immunohistochemistry and factor VIII antibodies. We also investigated the influence of suture techniques (circular anastomoses, n = 19; longitudinal sutures, n = 15) on vascular perfusion.
  
  
  RESULTS
  Only human samples showed branching of mesenteric vessels. Compared to the pig, human vessels showed closer connections at the entrance to the bowel wall (p = 0.045) and higher numbers of intramural anastomoses (p < 0.001). Porcine main vessels formed in multifilament-like vessel bundles and displayed few intramural vessel anastomoses. Circular anastomoses induced a circular perfusion defect at the bowel wall; longitudinal anastomoses induced significantly smaller perfusion defects (p < 0.001). Both species showed higher vascular density in the jejunum than in the ileum (p < 0.001). Human samples showed similar vascular density within the jejunum (p = 0.583) and higher density in the ileum (p < 0.001) compared to pig samples.
  
  
  CONCLUSIONS
  The results showed significant differences between human and porcine intestines. The porcine model remains the standard for studies on anastomotic healing because it is currently the only viable model for studying anastomosis and wound healing. Nevertheless, scientific interpretations must consider the anatomic differences between humans and porcine intestines.
authors.affiliation: Department of Vascular Surgery, RWTH Aachen University Hospital, Pauwelsstr. 30, 52074, Aachen, Germany, kvontrotha@ukaachen.de.
authors.forename: Klaus-Thilo
authors.initials: KT
authors.lastname: von Trotha
authors.forename: Nick
authors.initials: N
authors.lastname: Butz
authors.forename: Jochen
authors.initials: J
authors.lastname: Grommes
authors.forename: Marcel
authors.initials: M
authors.lastname: Binnebösel
authors.forename: Natascha
authors.initials: N
authors.lastname: Charalambakis
authors.forename: Georg
authors.initials: G
authors.lastname: Mühlenbruch
authors.forename: Volker
authors.initials: V
authors.lastname: Schumpelick
authors.forename: Uwe
authors.initials: U
authors.lastname: Klinge
authors.forename: Ulf P
authors.initials: UP
authors.lastname: Neumann
authors.forename: Andreas
authors.initials: A
authors.lastname: Prescher
authors.forename: Carsten J
authors.initials: CJ
authors.lastname: Krones
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000714:Anastomosis, Surgical / Q000379:methods; D000792:Angiography / Q000379:methods; D000818:Animals; D001707:Biopsy, Needle; D002102:Cadaver; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007413:Intestinal Mucosa / Q000098:blood supply / Q000473:pathology; D007421:Intestine, Small / Q000033:anatomy & histology* / Q000098:blood supply* / Q000601:surgery; D008297:Male; D008638:Mesenteric Arteries / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D008642:Mesenteric Veins / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D008875:Middle Aged; D013152:Splanchnic Circulation / Q000502:physiology; D018709:Statistics, Nonparametric; D013536:Suture Techniques; D013552:Swine