Equine amniotic membrane transplantation for corneal ulceration and keratomalacia in three horses.

This research paper investigates the use of the inner lining of a horse womb, known as the amniotic membrane, as a treatment for severe inflammation and erosion of the cornea in horses. The researchers found that the amniotic membrane was successful in preserving the structure and some vision of the horse’s eye, and in improving its appearance.

Study Background and Methods

• The study is based on the properties of amniotic membrane, which is anti-angiogenic (prevents formation of new blood vessels), antifibrotic (prevents the formation of excess fibrous connective tissue) and antiprotease (inhibits proteins that break down other proteins).
• The researchers wanted to explore whether these properties could help in treating severe corneal inflammation and degradation (keratomalacia) and corneal ulceration in horses.
• Equine amniotic membrane was harvested from a thoroughbred mare undergoing an elective Cesarean section. The membrane was frozen and thawed as needed for the study.
• The research examined the medical records of horses with keratomalacia treated at the University of Florida, specifically looking at those which received an amniotic membrane transplant (AMT) as treatment without any additional grafting procedures.
• Details regarding the post-AMT clinical descriptions, additional treatments, outcome, and the causes of keratomalacia were documented.

Study Results

• A total of three horses, which were suffering from corneal ulceration and keratomalacia, received AMT between December 2002 and April 2003.
• All three horses had a strain of the bacterium Pseudomonas in their eyes, with two of the horses also carrying a fungal infection.
• The conditions of the horses’ ulcers worsened despite aggressive medical treatment, affecting between 50% to 76% of the corneal diameter.
• Over a period of 4 to 6 weeks the AMT was naturally shed by the horse’s body.
• At their final checkup, all three eyes that received AMT showed improvements – they were comfortable, not needing medication, and the horses were able to perceive light and respond variably to the threat of nearby objects.
• All horses returned to their previous work, suggesting the AMT procedure held no long-term health impacts.

Study Conclusion

• The research concluded that amniotic membrane can be successfully used to preserve the structure and a certain degree of vision in the horse’s eyes affected by severe keratomalacia and corneal ulceration.
• In addition, the use of amnion also led to a better cosmetic outcome, i.e., the eyes looked healthier post-treatment.
• However, this conclusion is drawn from a small sample size, emphasizing the need for further studies with more samples to corroborate these findings.