The Horse's Perspective
An eyelash or a very small piece of debris gets in your eye or under your contact. Your eye begins to water uncontrollably and squint shut. Your eye becomes sensitive to touch and light, and it is very difficult to find and remove what is causing the issue.
Now imagine this same scenario with a horse, except they have no way to ease this discomfort. This is what a corneal ulcer feels like.
Eyes have a unique physiology and anatomy and they react quickly to any disturbance. Any damage to a horse's eye is considered an emergency.
What is a Corneal Ulcer?
The most common eye disturbance that horse owners will face is a corneal ulcer. An ulcer is a wound or lesion to the cornea which exposes the underlying layers. Most ulcers start out sterile, meaning there is no bacteria or fungus present. Sterile ulcers that are seen and treated promptly will typically heal within 7-14 days. However, if left alone, bacteria and debris can get into the ulcer ( just like a wound on the skin) and an infection can occur. Once this occurs, the cornea can abscess. If this infection can not be contained, it can lead to complete removal of the eye.
The green area in the eye is caused by a fluorescein stain that is used to diagnose and reveal ulcers.
What Causes a Corneal Ulcer?
- Trauma - a piece of grass/hay caught in the eye or a scratch caused by rubbing.
- Underlying issue such as immune mediated (allergies, uveitis) or metabolic issues (Cushings, insulin resistance).