A must-attend session for many of the practitioners at the American Association of Equine Practitioners’ annual convention is the Kester News Hour, which features a panel of expert practitioners who summarize recent research results from the areas of equine medicine, surgery, and reproduction. At the 2013 convention, held Dec. 7-11 in Nashville, Tenn., attendees welcomed Carol Clark, DVM, Dipl. ACVIM, of Peterson & Smith Equine Hospital, in Ocala, Fla., to the Kester panel for the first time, and listened as she offered concise equine medicine literature reviews.

Ophthamology

Clark began by describing research surrounding equine eye conditions, highlighting a paper in which researchers reviewed the clinical signs, diagnostic methods, and treatment options for equine subepithelial keratomycosis, a fungal infection of the eye. They found that one-quarter of these cases have a “punctuate” appearance (with little specks dotting the eye), Clark reported, while half the cases have a more diffuse appearance. The remaining one-quarter of cases present with both features. The team also found that the best way to diagnose these cases is by obtaining a cellular sample for culture and evaluating the structure of the cultured fungus to identify it, she said. Another helpful diagnostic tool is horses’ response to antifungal treatment—Clark said nearly all the cases resolved within four to five weeks of using this approach. She remarked, “It is yet unknown if this is the beginning of an ulcerative fungal infection or its own disease entity.”

Next, Clark shared a study in which researchers evaluated the use of topical anesthetics for numbing the horse’s eye for veterinary ophthalmic procedures. While proparicaine has always been the preferred ophthalmic anesthetic, the authors indicated that other topical choices are just as effective, such as lidocaine and bupivicaine. They determined that mepivicaine does not achieve complete anesthesia, Clark cautioned, but the other anesthetics’ effects were usually apparent within a minute, with a maximum effect observed within five minutes of topical treatment.

Clark also touched on a study in which scientists examined eosinophilic keratitis in mid-Atlantic states. Researchers found that this invasion of the equine cornea with a type of white blood cell tends to be a summer syndrome, with 92% of cases occurring between June and October. Almost half of the cases evaluated were recurrent, with horses having been infected in previous years. The typical healing time for eosinophilic keratitis cases is about 3.7 months, Clark said, and topical corticosteroid treatment did not decrease healing time. On the contrary, systemic corticosteroids (such as dexamethasone) shortened healing time by 2.2 months, and cetirizine (an antihistamine) lessened the chance of recurrence