Horses injure their eyes often enough that, even on a small farm, you’ll likely face one of these injuries sooner or later. How you handle the problem can make the difference between a successful outcome and loss of vision that ends or limits a horse’s career.
The short and quick answer is: call the veterinarian at the first sign of eye trouble. “If a horse has any sort of injury to or around the eye, I want to see him that day,” says Bruce Kuesis, DVM, an equine practitioner in Santa Barbara, Calif. Why? Eye injuries that seem minor may not be, and small problems can rapidly blossom into big ones when left untended.
What to Look For
Potential eye injuries are one good reason (but certainly not the only one) to check every horse thoroughly on a daily basis. Call the vet if you see obvious damage to an eye, or any of these signs:
• The horse blinks rapidly or won’t open the eye.
• The eye or lid is swollen.
• The eye is tearing heavily, or there is other discharge.
• The sclera (whites of the eye) or conjunctiva (membranes around it) are red and inflamed.
• A white film clouds any part of the cornea (the eye’s clear outer covering), or the cornea has a cloudy, bluish look.
• An eyelid is cut or torn. Whatever caused the wound may have damaged the eye as well.
These signs don’t always spell disaster. The eye may be red and tearing simply because it’s irritated by windblown dust, for example. But if the horse is in pain, he may not let you get a really good look at the eye—and even if you succeed, eye injuries can be difficult to assess without veterinary knowledge and equipment.
While you’re waiting for the vet, you can give some basic first aid. If the horse will allow it, gently rinse the eye with sterile saline solution to wash out dust and other foreign objects. Get someone to hold the horse; you’ll need to hold the lid open with the thumb and forefinger of one hand while you apply the saline with the other. You can use contact lens solution for this if you don’t have saline in your first-aid kit.
If the horse isn’t willing to let you rinse his eye, don’t push it. The veterinarian will be able to tranquilize the horse and flush the eye if necessary. Meanwhile, put a fly mask on the horse, to keep flies away from the injury, and let him chill out in a stall until the vet arrives. Bright light can worsen eye pain by causing pupils to contract, so a dark stall is best.
If you have some on hand, you may put the proper ointment in the eye to help, but check with the vet first. Using an ointment with a corticosteroid such as dexamethasone on a corneal cut can make matters worse. The vet will check for serious problems. Two common ones are corneal ulcers and uveitis, either of which can cost the horse his vision if overlooked.
Damage to the cornea is always cause for concern, says Dr. Kuesis. A blow, a foreign object, or just rubbing an irritated eye can scratch the surface. This type of injury, called a corneal ulcer, is painful and prone to infection. A serious ulcer may leave the cornea scarred. Left untreated, infection can cause the eye to rupture.
Tiny abrasions on the cornea are nearly impossible to see plainly, so the veterinarian will float a fluorescent dye over the surface of the eye to make them stand out. If the cornea is scratched, the vet will probably prescribe antibiotic eye ointment or drops to prevent infection and an oral nonsteroidal anti-inflammatory drug (NSAID), such as Banamine, phenybutazone, or aspirin. (Corticosteroids, which are powerful anti-inflammatories, aren’t used because they can interfere with corneal healing.) Atropine, another topical medication, can ease eye pain by preventing the pupils from contracting. The horse should stay out of bright light and wear his fly mask while the injury heals.
Treated promptly, minor scratches often heal within a matter of days. If bacteria or—worse—fungi take hold, you may be looking at weeks of treatment. Persistent infections may require medication every few hours, sometimes round-the-clock; and medicating a horse’s eye isn’t easy, especially if the horse is in pain. If the horse is difficult, Dr. Kuesis suggests, the vet may be able to put in a subpalpebral lavage system, in which thin tubing is run through the eyelid and sutured in place; medication can then be injected through the tubing into the eye. The system can also be used with a medication pump that constantly treats the eye.
Another option is to send the horse to a clinic for treatment. A clinic with a veterinary ophthalmologist can also perform surgery, such as corneal grafts. When other measures fail, removing the eye brings the horse relief from pain.
A blow—blunt trauma—may simply bruise the eyelid and cause swelling and redness around the eye. But it may also cause the eye itself to become inflamed, even if there’s no damage to the cornea. The vet can check for signs of deeper inflammation with an ophthalmoscope.
Uveitis is the medical term for inflammation within the eye. “It can be a medical emergency because delay creates more potential for long-term damage,” says Dr. Kuesis. The initial inflammation may set the stage for repeated episodes—recurrent uveitis, a condition known to many as moon blindness. (Other causes, including several diseases and infections, can also lead to this condition.) Inflammation can cause the iris to stick to the lens, leading to cataracts, or to the cornea, causing scarring. Fluid buildup within the eye can lead to glaucoma. Bleeding within the eye is also possible. Any of these effects can lead to reduced or lost vision.
Uveitis calls for quick and aggressive treatment with anti-inflammatory drugs. As long as there’s no scratch to heal, topical corticosteroids can be part of the program. The sooner the inflammation is brought under control, the lower the risk of complications.
You can’t prevent eye injuries entirely, but common-sense steps can cut risks for the horses at your stable.
• Patrol stalls and paddocks for anything that could injure eyes—protruding nails, sharp edges on troughs and other equipment. Be sure everything is hammered flat, rounded off, covered, or removed. A horse can cut an eye on the end of a bucket handle, where it loops through the rim; cover the sharp end with duct tape.
• Use fly masks and/or roll-on repellents to keep insects away from horses’ eyes. Flies cause irritation, the horse rubs, and before you know it he has a corneal ulcer.
• On trails, avoid routes with low branches and don’t “bushwhack” through heavy brush. Branches can do serious damage to an eye.
Remember that it’s smart to be an alarmist about eye injuries—the horse’s vision is at stake.