No one knows how a 10-year-old Quarter Horse mare named Annie sustained a tiny puncture wound to her left eye, which resulted in the eye developing a corneal abscess. But, when Annie arrived at the clinic in early October her eye was so painful that she was unwilling to open it.
The possibility that Annie would lose her eye was very real, and developing a successful treatment plan took the collaboration of several doctors. Mid-Rivers has developed a network of colleagues and veterinary specialists across the United States that they confer with when confronted with unusual or difficult cases. Collaborating on cases helps the doctors at Mid-Rivers ensure their patients receive the best possible care.
After some discussion among the doctors at Mid-Rivers Equine Centre, they decided to consult with Dr. Dennis Brooks, who is the Ophthalmology Service Chief for the Department of Small Animal Clinical Sciences at the University of Florida – College of Veterinary Medicine. His research interests include corneal transplantation in horses and glaucoma in all animals. Dr. Brooks is also the author of Ophthalmology for the Equine Practitioner.
The doctors discussed several treatment options including: medical therapy, a conjunctival flap surgery, or a corneal transplant. Medical therapy is the least invasive of the treatment options, and ultimately was how Annie was treated. However, if medical therapy had not been successful, surgical intervention would have been necessary to save her eye. A conjunctival flap surgery involves cutting a small “flap” into the pink soft tissue (conjunctiva) surrounding the eye and then suturing the flap over the damaged area of the cornea. This establishes blood supply to the injured area and expedites healing. However, due to Annie’s corneal abscess this option may not have been the best choice, as her cornea was so diseased. If medical therapy had not been successful for Annie, the best surgical option for her would have likely been a corneal transplant. During this procedure the damaged cornea is removed and replaced with an intact cadaver cornea.
Medical therapy was initiated and a cocktail of medications were prescribed: voriconazole (to prevent the development of a fungal infection), ciprofloxacin (an antibiotic to address bacterial infection), atropine (to dilate the pupil and make Annie more comfortable), banamine (to decrease inflammation and pain) and lastly serum from Annie’s own blood to encourage healing (anti-enzymatic properties).
As you can imagine, a horse may not always be cooperative for eye medications that must be given multiple times a day, when their eye is painful. Therefore, in complex eye cases a subpalpebral lavage tube is utilized to deliver the eye medications. A subpalpebral lavage tube is inserted through the lower eye lid and the tubing is run up the horse’s face, forehead and pole and is then braided into the mane where an injection port allows easy delivery of the medications without handling the horse’s eye directly.
Annie began her eye treatments in October and spent nearly 28 days in the hospital. The frequency with which Annie needed to be medicated was intensive and her progress needed to be closely monitored at a hospital. Each week Annie’s eye showed improvement and once the treatments were only needed twice a day, Annie was sent home.
After arriving back home Dr. Herath made follow-up visits to the farm. These photos are from one of the follow-up calls that resulted in Annie’s tube being removed.
Luckily, medical therapy worked and a corneal transplant was not needed. Dr. Herath and her colleagues helped Annie retain her eyesight. There is some scaring from the healing process that you can see in one of the pictures. (The eye has been stained with a green dye to evaluate the cornea for ulceration or damage). The scar is the white area just to the right of the center of the eye. Dr. Herath stated “Over time the scar will become smaller. Although Annie’s vision will be impaired by the scar to some degree, she will still have vision and will get along just fine.”
Annie is a 2002 Quarter Horse mare out of Tom Heitman‚Äôs (her owner) World Champion barrel racer. Today Tom is busy raising a young family and doesn‚Äôt competitively barrel race so Annie has become the ‚Äúfamily‚Äù horse. He enjoys watching his young son light up when he gets to sit atop Annie – a job Annie is more than capable and willing to do.