Q: My husband is boarding a 10-year-old Tennessee Walking Horse mare for a friend. When she was loaded in the trailer, she bumped the outside of her eye and split the flesh straight out from the corner about a half inch. It did not damage her eyeball. She has bumped it a couple of more times since then and is extremely head shy due to the discomfort. The top eyelid is swollen. Should this have been sewn up by a veterinarian at the time it was done, and is there anything besides keeping it clean and applying antibiotic salve to help the healing? We had this same thing happen a few years ago, and the horse’s eye healed up fine without any scarring or problems of this sort.

—Dianee Hardy, via e-mail

A: Your questions are all good ones—they address specific facts about the eye that every horse owner should understand.

First, if a horse rams its head, which weighs around 60 pounds, into a hard object like a trailer, either the sinus cavities or the orbit can be fractured. The sinus cavities are each about the size of a pack of cards, and the bone that covers them is thinner than a cracker. The orbit is a ring-like socket of bone that frames the eyeball, and much of it is only as thick as your thumb. Fractures of either of these fragile structures can result in serious infections. They also can pinch the tissues around the eye, blocking the tear duct or altering the mobility of the globe. And even if the outside of the eye looks normal, really hard blows can cause bleeding inside the eye or disruption of the lens or retina. Such injuries can be blinding