Catastrophic Ocular Surface Failure in the Horse (AAEP 2010)

These are treated with topical antiviral medication. The entropion might cause increased tearing, eyelid squinting, conjunctivitis (inflammation of the conjunctiva that lines the inner eyelids), or corneal ulcers. At that point, treating and managing ERU becomes the priority. Blunt trauma, e.g., a pop in the eye with a polo ball, can create inflammation and propagate uveitis. Granulae iridica cysts are typically small enough to have little to no effect on horses’ vision, meaning affected animals are suitable for purchase. Only one patient had both an aqueous and vitreous tap. This time, however, the gauze should not be soaked in betadine.

Also, if the eye is blind and painful, he said it should be removed. Consider using a hood or flymask to help protect the SPL insertion site. Clinical signs include visual impairment in the dark with generally normal vision in daylight. Brooks also recommended examining the eyelids for potential abnormalities. “If no severe pathology is identified needing immediate attention, the eyelid swelling can be treated overnight with systemic nonsteroidal anti-inflammatory drugs (NSAIDs) therapy,” she said, noting that the exam should continue the next day. “The clinical diagnosis of ERU is based on the presence of characteristic clinical signs and a history of documented recurrent or persistent episodes of uveitis,” Gilger said. He reminded veterinarians in attendance that high-dose systemic NSAIDs (non-steroidal anti-inflammatory drugs given intravenously, intramuscularly, or orally) slow vascularization (blood supply) and, thus, can slow healing.

Blindness occurs in nearly all horses with glaucoma. Corneal blood vessel formation is rarely present in the early stages of corneal abscessation (see Figure 1 above), although stromal abscesses do not heal until blood vessels grow into them. It was this tenacious design that inspired the inventor of Velcro. As mentioned above, Pseudomonas species are normal bacteria found in soil and, in addition, several reports have demonstrated that Pseudomonas species are part of the normal flora of the eye. Most likely not, but it never hurts to rule it out. Christa Lesté-Lasserre is a freelance writer based in France. Horses have an amazing ability to compensate for vision loss, especially if one eye is primarily affected and the loss was gradual in development.

Currently, Erica competes in eventing with her OTTB, Dorado. Conjunctiva–The conjunctiva is important to the immune system of the eye. Czerwinski cautioned that while this procedure has a high short-term success rate, the long-term success rate is less favorable. Additionally, he noted, many ectropion cases are actually innocuous and no surgical or medical intervention is required. Besides, surveys are conducted to find out the ailments of horses needing maximum research (AAEP, 2004). Alexandra Beckstett, Managing Editor of The Horse and a native of Houston, Texas, is a lifelong horse owner who has shown successfully on the national hunter/jumper circuit and dabbled in hunter breeding. Bacteria living on the surface of the cornea are able to attach to the corneal cells once the epithelium has been damaged.

The study, “Ocular dimensions, corneal thickness, and corneal curvature in quarter horses with hereditary equine regional dermal asthenia,” was published in Veterinary Ophthalmology. Horses with the more severe form of MCOA are homozygous (having inherited the same allele from both parents) for the mutant gene. In their study, Cadoré and his colleagues investigated the eyes of Comtois horses and Rocky Mountain Horses carrying at least one copy of the allele and compared their results to horses of the same breeds without the PMEL17 gene. A shallow ulcer involves just disruption of epithelial cells, while a deep ulcer would involve additional significant loss of stroma. The session started with a discussion about diagnostic techniques for fungal keratitis (corneal inflammation) and also covered treatment modalities including antifungal medications, use of a subpalpebral lavage system for delivering medications to the eye, and when to change medications. Redness, swelling, pus, pupil constriction in the dark, cloudiness, squinting, and sensitivity to light are common symptoms. ACVO, Professor of Ophthalmology at University of Florida College of Veterinary Medicine, during the first AAEP Focus on Ophthalmology meeting, held in Raleigh, N.C., in October.

Made of a multitude of individual fibers, the lens is suspended in place by zonules (ligaments holding the lens in position) attached to the ciliary body. Occasionally veterinarians stumble across a drug side effect that’s more useful than detrimental. Dennis Brooks, DVM, PhD, Dipl. Unless your mare has had a bad breakup with the stallion next door, her watery eyes could indicate a serious problem. Q:I was wondering about corneal ulcers. A horse’s body temperature can indicate everything from an internal ailment (such as colic) to an infectious disease to hypothermia. The horse’s eye position in the skull allows for a large, nearly 360° field of vision–approximately 146° of monocular vision on either side and about 65° to 80° of binocular vision ahead of them.

Emerging EHV-9 infections are of special interest because there is a wide range of susceptible hosts, which includes mice and rats,13 hamsters,12 goats,35pigs,26 dogs and cats,37,38 and common marmosets.21 Recently, EHV-9 was used to induce encephalitis in hamsters by different routes of inoculation, including the oral (25%), peritoneal (25%), and ocular (75%) routes; however, the intravenous route failed to induce encephalitis and there were discrepancies in the distribution of EHV-9 antigen immunoreactive cells in the location and severity of the cerebral lesions.