b'AAEP FORUM BRETT ROBINSON, DVMTheHorse.com/AAEP-ForumCommon Equine Eye ConditionsE ye problems in horses are extremelytissues. Causes include allergies and in-common. Last year alone, our groupsect hypersensitivity, which can be treated practice performed 100 eye exams onwith anti-inflammatories, antihistamines, horses experiencing signs of eye diseaseand environmental modifications.or trauma. If you have ever dealt with anUveitis is an inflammatory condition equine eye problem, you know the impor- of the middle layer of the eye. Complica-tance of early recognition and appropriatetions associated with uveitis are the No. treatment. Here are some common condi- 1 cause of blindness in horses worldwide. tions and how your veterinarian mightUveitis is categorized as acute or chronic/manage them. recurrent. Vets base their initial diagnosis To begin an eye exam, your vet will re- on clinical signs of squinting, ocular dis-COURTESY DR. BRETT ROBINSONview your horses medical history. Then hecharge, corneal edema (swelling), blood or she will evaluate the horse for comfortor pus in the anterior (front) chamber, and eye symmetry, examine the structuresand miosis, among others. Uveitis is im-surrounding the eyeball, assess vision andmune-mediated and has multiple causes, reflexes, apply a fluorescein stain, andboth infectious (Leptospirosis, Strepto-examine the back of the inside of the eyecoccus, equine influenza, and equine using a magnifying lens with a specialHorses are vulnerable to eye trauma because ofherpesvirus, to name a few) and non-light source. Certain conditions involvethe size and location of their eyes. infectious (trauma or tumors). Certain measuring intraocular pressures andbreeds, such as Appaloosas, are at higher dilating the pupil. In all cases treatmentneed medication every few hours andrisk for uveitis. Sometimes a cause isnt goals are to preserve vision, decrease pain,close monitoring. If a corneal ulcer fails toapparent, and it must be treated symp-and prevent infection and recurrence.respond to medical therapies, is signifi- tomatically. Treatment consists of topical Horses are particularly vulnerable tocantly deep, or has a melting appear- medication to dilate the pupil, topical ocular trauma because their eyes are largeance, vets usually recommend surgery toanti-inflammatories (corticosteroids or and positioned on the sides of the head.remove the dead and infected tissue andnon-steroidal anti-inflammatories), topi-Corneal ulcers are one of the most com- place a conjunctival graft. If corneal ulcerscal immunomodulatories, and systemic mon eye conditions caused by trauma.are treated early and aggressively, theanti-inflammatories. Most horses with The cornea is a transparent membrane inprognosis for vision can be good.the acute form initially respond well to the front of the eye. Fluorescein stain dyeEyelid lacerations are also commonsymptomatic treatment, but long-term adheres to defects, making them moreresults of trauma. The classic case is anprognosis might be guarded because visible. Corneal pathology (disease oravulsion (tearing) that occurs when theof recurrence, and each episode causes damage) generally results in opacity, andhorse catches his eyelid on a hook- further eyedamage. various color changes can accompany thisshaped object (like the J on a bucketMedical therapies for eye disease can process. Other signs include squinting,handle). After examining for concurrentbe prolonged and fraught with complica-eyelid swelling, and discharge.eye damage, the veterinarian usuallytions. In cases that cannot be treated for Corneal ulcer treatment and prognosissedates the horse, administers local anes- financial or medical reasons, enucleation depend on the defects depth. For uncom- thesia, prepares the skin, and repairs the(removing the eye) can be curative. Study plicated (small and superficial) ulcerslaceration. Aftercare typically involves sys- results show that horses can return veterinarians might prescribe a topicaltemic anti-inflammatories and antibiotics.successfully to a variety of disciplines antibiotic to prevent infection and an oralIf treated promptly, prognosis is good. following enucleation, and owners report anti-inflammatory. If the pupil is smallAnother common eye issue is conjunc- satisfaction with the procedure and (a pain response called miosis), he or shetivitis. The conjunctiva is the mucousoutcome. might apply a topical medication such asmembrane covering the inside of theIf you suspect an issue with your atropine for dilation. For complicated (in- eyelids and white part of the eye. Clinicalhorses eye, remember that early detec-fected, deep, large-diameter) ulcers, hospi- signs of conjunctivitis include oculartion and veterinary attention will help tal referral is ideal, because the eye mightdischarge, redness, and swelling of theseensure the best possible outcome.hAmerican Association of Equine Practitioners, 4033 Iron Works Parkway, Lexington, KY40511859/233-0147www.aaep.org8May 2020The Horse|TheHorse.com'