Suspected eye injuries are always emergencies.
A horse with a squinting eye, or tears and discharge can be very serious. The difficult thing is that minor problems such as allergies or dust irritation can mimic the extremely serious conditions that may threaten your horse’s vision.
This case presented in a typical fashion: a horse with some squinting and a few clear tears coming down from the left eye. One indication of the severity though is the amount of eyelid closure – fully closed lids with that much force is always serious in my experience.
We still don’t know what’s going on yet though. One of the first steps is gaining proper examination of the eye structures. Nerve Blocks with anesthetic at specific areas around the eye lets us safely open the lids to do our exam. Staining with special fluorescein dye shows us the severe extent of the corneal ulcer in green. These ulcers are missing the top layer of the corneal covering. Trauma, foreign bodies (grass awns or burrs), and bacterial infections can all cause corneal ulcers.
It is EXTREMELY important to know if corneal ulcers are present anytime your horse has a sore eye. With proper treatment, ulcers can be cured with no long term effects. However, some eye medications will actually make the ulcer WORSE! Never use your friend’s leftover eye ointment they used on their horse because it might be the wrong choice.
Despite the large size, this ulcer repaired itself after a course of topical antibiotics and oral pain meds to keep the horse comfortable.