Corneal Ulcers in Horses



Treatment varies based on the severity of the corneal ulcer. In all cases, it is vital that the horse be removed from bright light. This means keeping the horse inside during the time of day when the sun is high and covering the eyes with blinders or shades to protect them from light.


Leaving corneal ulcers untreated can create a potential risk for loss of sight. Untreated ulcers may cause scar formation on the cornea, and if deep enough, may actually cause rupture of the eyeball, resulting in loss of that eye. This is a very painful process. For these reasons, immediate and effective treatment of even the smallest ulcer is highly important. Your veterinarian, once alerted to the possibility of an eye injury, will treat the injury with the serious attention that is required.


A secondary infection is one of the more common side effects of a corneal ulcer, and this is the main reason for immediate treatment. Based on the laboratory results from the corneal scrapings, an antibiotic or antifungal ointment or drops may be administered to help clear up the infection. Even without clinical signs of infection, your veterinarian will prescribe an antibacterial ophthalmic ointment to administer multiple times a day to aid in healing of the eye.


Sometimes, the ulcer is so large or deep that the horse will require medication several times a day. In this case, or a case where the horse is unwilling to allow you to put ointment in its eye at all, your veterinarian may choose to place a subpalpebral lavage system in the horse’s eye. This simple medical device is a small, thin, flexible tube that is sutured underneath the eyelid. The tube is then wound back behind the horse’s head and down its neck where there is port where the medication is administered. This prevents you from having to get close to the horse’s eye to deliver medication. After the ulcer has healed, the subpalpebral lavage system is easily removed by your veterinarian.


In very severe cases or cases where the ulcer is not healing, surgical treatment may be needed, with unhealthy tissue removed from the eye. In the most severe cases, a corneal transplant may be called for.


Living and Management


Enough time should be given to the horse to allow for full healing of the eye after a corneal ulcer. Care will need to be taken to ensure that further damage is not done to the eye, either the surrounding environment -- such as with dust, flies, etc. -- by contact with other horses or while being exercised. Some horses will become spooky on the side where they had the corneal ulcer. Take time to work with your horse so he regains confidence and overcomes this behavioral side effect.