One of the many wonders of breeding for specific characteristics is that dogs and other animals have been selected to match a breed standard or set of characteristics that makes that dog unique from other dog breeds. Unfortunately in some of the unique breeds that have developed there are health issues associated with the very characteristics that define the breed. Often these health issues developed before early breeders understood the impact of breeding for certain characteristics, or even the risk of breeding dogs that exhibited certain traits. Exposure keratopathy syndrome is one such example that is very prominent in some breeds due to the specific eye formation that defines the breed.

Exposure keratopathy syndrome occurs when there is a problem with the ability of the eyelids to close or close properly to keep the eyeball moist and free from debris and irritants. There are three major causes of the syndrome and they include exophthalmus, lagophthalmus, and macroblepharon.

In simple English exophthalmus means a protruding eyeball. This is often described in the breed standards as a "prominent eye". Breeds that are bred for a prominent eye include Pugs, Boston Terriers, Pekingese, Shih Tzu, and Lhasa Apso. Lagophthalmus often goes along with exophthalmus and occurs when the eyelids are too small to completely close over the eye. This is usually most easily seen when the dog is sleeping and the eye is visible between the lids. The brachychephalic or short muzzled breeds are most prone to these two conditions.

Macroblepharon occurs when the lower lid is very loose and large and is not tight against the eye. Even when these dogs blink the lower lid stays out from the eye, preventing a full moistening of the lower part of the eyeball. Some of the breeds that are more prone to this condition include the Basset Hound, Bloodhounds, Mastiffs, Cavalier King Charles Spaniels, St. Bernard, Newfoundland, and the American Cocker Spaniel. These are often the "sad eyed dogs" and often their eyes may appear red and irritated.

In all three types of exposure keratopathy syndrome the eyes will be red and irritated and may have a thick discharge or tearing. The dog may rub at his or her eyes and debris may be evident in the eye. If untreated corneal injury can occur that will, over time, lead to decreased vision and even blindness. Tear substitutes such as artificial teardrops can be used temporarily but the most effective and long term treatment to prevent further eye damage is surgery to increase the eyelid size and provide protection for the eye. In some cases, especially with macroblepharon, entropion, or a rolling inward of the lower lid, will also need to be corrected.

For dogs that have infections, the infection in the cornea will need to be treated prior to surgery so topical and oral antibiotics will be prescribed. Regular washing and cleaning of the area around the eye to remove any dirt or debris will be very important at this time. Early detection and treatment is the very best possible option and owners should have the dog's eyes checked if they appear red, irritated or the dog is pawing or rubbing his or her eyes on a regular basis.