A topographic anatomical study of the equine epiploic foramen and comparison with laparoscopic visualisation.

This research study delves into the detailed anatomy of the equine epiploic foramen and its related structures, particularly as it pertains to observations from laparoscopic images, to help improve surgical interventions for diseases related to this anatomical feature.

Objective and Methods

• The primary objective of this study was to provide a comprehensive description of the anatomy of the equine epiploic foramen and omental vestibule. This included detailing their defining structures and quantifying the dimensions of the epiploic foramen, then comparing the results with laparoscopic images.
• The research was conducted through a descriptive study that employed cadaver material and laparoscopic images from the horses that were euthanised due to reasons unrelated to the research objective.
• A total of 32 horses were under observation, from which two cadavers were chosen for making vascular casts of the coeliac artery and portal vein.
• In 30 cadavers, the epiploic foramen and omental vestibule were casted using a polyurethane prepolymer, which acted as a landmark during dissection. The circumference of the epiploic foramen was measured from these casts.

Results

• Several key structures were identified and found to define the epiploic foramen and omental vestibule, including hepatoduodenal ligament, hepatogastric ligament, and gastropancreatic and hepatopancreatic folds.
• Part of the hepatic artery was discovered within the hepatoduodenal ligament, and all these structures were visibly clear through the laparoscopic procedure.
• There was also an identification of a secondary fold within the hepatoduodenal ligament, which became the ventral border of the epiploic foramen and is composed mainly of elastin fibres.
• The average circumference of the epiploic foramen was calculated to be 11.6 ± 2.6 cm. It was found to be positively correlated with the body weight of the horse, but showed no association with age or gender.

Conclusion

• The results corroborated that several clinically relevant structures delineate the epiploic foramen and comprise elastin fibres.
• The study concludes that comprehensive knowledge of the anatomy of the epiploic foramen, as well as the use of laparoscopic images, can be extremely valuable for surgeons in devising interventions to treat diseases related to the equine epiploic foramen.