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Third eyelid cartilage eversion in an adult mare
Albert L D'Agostino1, Elizabeth A Giuliano1, Keiichi Kuroki2
1Department of Veterinary Medicine and Surgery, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, USA.
Veterinary Ophthalmology
|October 11, 2024
Summary
This study details the first reported case of third eyelid cartilage eversion in an adult horse. Surgical removal of the abnormal cartilage in this American Quarter Horse mare resulted in a full recovery.
Area of Science:
- Veterinary Ophthalmology
- Equine Surgery
Background:
- Third eyelid cartilage abnormalities are uncommon in horses.
- Acquired conditions affecting the nictitating membrane require thorough investigation.
Observation:
- A 22-year-old American Quarter Horse mare presented with a two-week history of left third eyelid abnormality.
- Ophthalmic examination confirmed third eyelid cartilage eversion of the nictitans.
Findings:
- Surgical excision of the everted cartilage was performed using electrocautery.
- Histopathology revealed normal cartilage with mucosal hyperplasia and submucosal vascularity, ruling out neoplasia or inflammation.
- The mare healed well post-surgery with restored normal third eyelid conformation.
Implications:
- This case represents the first documented instance of acquired, presumed spontaneous, third eyelid cartilage eversion in a horse.
- Highlights the importance of surgical intervention for correcting such abnormalities.
- Contributes to the understanding of equine ocular conditions.
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