title: A topographic anatomical study of the equine epiploic foramen and comparison with laparoscopic visualisation.
abstract: BACKGROUND
  There are no previous studies correlating the anatomy of the equine epiploic foramen and its defining structures with laparoscopic images.
  
  
  OBJECTIVE
  The purpose of this study was to describe the precise anatomy of the epiploic foramen and omental vestibule, to quantify the dimensions of the epiploic foramen and to relate these findings to laparoscopic images.
  
  
  METHODS
  Descriptive study of cadaver material and laparoscopic images.
  
  
  METHODS
  Thirty-two horses subjected to euthanasia for reasons unrelated to colic were studied. Two cadavers were used to make vascular casts of the coeliac artery and portal vein. In 30 cadavers the epiploic foramen and omental vestibule were cast with a polyurethane prepolymer immediately after euthanasia. The cast served as a landmark during dissection and the circumference of the epiploic foramen was measured from these casts. Histology was performed on structures defining the epiploic foramen in 2 horses. Laparoscopic images from 6 standing right flank procedures were reviewed.
  
  
  RESULTS
  The defining structures of the epiploic foramen and omental vestibule are the hepatoduodenal ligament, hepatogastric ligament and the gastropancreatic and hepatopancreatic folds. The hepatoduodenal ligament has a secondary fold which forms the ventral border of the epiploic foramen, consisting of a central connective tissue core of mainly elastin fibres. The hepatic artery for part of its course is incorporated in the hepatoduodenal ligament. All these structures are clearly visible laparoscopically. The mean circumference of the epiploic foramen is 11.6 ± 2.6 cm and its circumference is positively correlated with body weight but is unrelated to age or gender.
  
  
  CONCLUSIONS
  Several clinically relevant structures delineate the epiploic foramen. Its defining structure consists, in part, of elastin fibres. Anatomical and laparoscopic knowledge may assist surgeons in developing interventions to treat diseases involving the epiploic foramen.
authors.affiliation: Department of Surgery and Anaesthesiology of Domestic Animals, Faculty of Veterinary Medicine, Ghent University, Belgium.
authors.forename: T
authors.initials: T
authors.lastname: van Bergen
authors.forename: M
authors.initials: M
authors.lastname: Doom
authors.forename: W
authors.initials: W
authors.lastname: van den Broeck
authors.forename: P
authors.initials: P
authors.lastname: Wiemer
authors.forename: P D
authors.initials: PD
authors.lastname: Clegg
authors.forename: P
authors.initials: P
authors.lastname: Cornillie
authors.forename: A
authors.initials: A
authors.lastname: Martens
mesh_terms: D000818:Animals; D002102:Cadaver; D005260:Female; D006736:Horses / Q000033:anatomy & histology*; D010535:Laparoscopy / Q000662:veterinary; D008297:Male; D009919:Orchiectomy / Q000379:methods / Q000662:veterinary; D010052:Ovariectomy / Q000379:methods / Q000662:veterinary; D010529:Peritoneal Cavity / Q000033:anatomy & histology*
keywords: anatomy; colic; epiploic foramen; horse; laparoscopy