Write an article based on this "Distinguish between a healthy and diseased eye. Realize the importance of getting medical attention. Make your horse more comfortable. Monitor your horse's progress."
Both eyes should appear symmetrical when you look at the horse head on. Both eyelids should open to the same extent, the whites of the eye should be white, the pupils (dark central part within the eye) should both be the same size, and the eyes should be clean, clear and bright. Look for the following, which may indicate problems with the eyes:  Swelling of just one eye or eyelid A red eye or eye with angry blood vessels in what should be the white part of the eye One pupil that's larger than the other Jumps or lines in the surface of eye, which could indicate a scratch or ulcer Yellow or green discharge (Occasionally, when it's very dusty the eye may wash dust out of the eye in which case you will see a clear goopy discharge in the inner corner of the eye. This can be normal.) Squinting or avoiding sunlight An eye that looks red, cloudy or sunken An eye that the horse keeps closed An excessive amount of tear fluid, such that the eye is constantly watering The whites of the eyes are puffy and swollen The surface of the eye doesn't look clear and shiny but is dull or glazed with white If you notice anything unusual about your horse's eyes, call the vet. There are many potential causes of eye problems in horses, from allergy, trauma, and debris, as well as other diseases. These need to be professionally diagnosed and the correct treatment started, in order to preserve the horse's eyesight. Neglecting to act or ignoring the horse has a problem could endanger the horse's sight. Be aware that some conditions may require lifelong treatment, like Equine Recurrent Uveitis. The sooner you start caring for your horse's eye conditions, the better chances he has of recovering or living comfortably. Before the veterinarian arrives to examine your horse, take a moist, clean cloth to remove any discharge from around the eye. You should also shield the horse from direct sun. Put blinders or a fly mask on your horse to help protect the horse from direct sunlight. Alternately, you can move the horse inside. All of these things can make your horse more comfortable and reduce strain on troubled eyes. Some conditions such as recurrent equine uveitis are aggravated by sunlight and UV, so keeping the eyes protected is important. If the eye seems to worsen or doesn't improve within several days, it's best to have your vet come back out for an exam. Ulcers can sometimes increase in size, and even threaten the inner part of the eye if not treated aggressively from the beginning of treatment. Don't use ointments or medications without your veterinarian's approval. When it comes to treating your horse's eyes, the vet is the most knowledgeable person to quickly care for your horse.