Equine Eye Conditions
EYE EMERGENCIES
Eye disease or injuries are common equine problems which can affect horses or all ages and sizes. Many eye conditions are medical emergencies that require veterinary attention straight away as most are painful and many can affect vision in the short and long term. A complete and thorough examination is always required, involving specialized equipment, dark surroundings and a manageable horse.
CONJUNCTIVITIS
Conjunctivitis is essentially inflammation of the conjunctiva (pink membrane lining the eye). Generally both eyes are affected and symptoms you will see include discharge (clear to purulent) and reddening and swelling of the conjunctiva. In severe cases the eyelids may be stuck shut with large amounts of discharge running down the face. Conjunctivitis is most frequently caused by infection or environmental irritation (flies/ dust) but can also accompany other ocular diseases such corneal ulcers etc. Most cases will clear with topical ointment although occasionally additional further treatment such as flushing the tear ducts is required.
CORNEAL ULCERS
Any physical insult to the cornea will result in abrasion and corneal ulceration. Most commonly it is from external trauma or foreign bodies (e.g. grass seeds) however they can also arise from eyelid abnormalities (e.g. entropion on foals, ectopic cilia). Sudden onset is common and the eye is usually painful. Symptoms include squinting, excess tear production or discharge and changes in corneal opacity/colour. A fluorescein stain is required to highlight the ulcer so we can assess extent and severity and is used at all follow up appointments to track healing.
Corneal ulcers should be considered an emergency as ulcerations can quickly progress from superficial to deep causing permanent damage or loss of vision. Treatment varies according to severity and will generally include topical ointment and oral pain relief.
UVEITIS
Uveitis is inflammation of the anterior (front) chamber of the eye. It is a very painful condition that can arise from trauma, occur secondary to systemic illness or accompany corneal disease. Symptoms you will see include swollen eyelids, squinting and increased tear production. The eye itself often appears grossly red or blue depending on the degree of conjunctival and corneal involvement. Treatment involves a combination of topical ointments and anti-inflammatories.
TREATING YOUR HORSES EYE CONDITIONS
Treating your horse’s eye conditions can be a challenging and frustrating process if your horse is not amenable to treatment. Commonly treatments will involve some sort of topical medication that can be either ointment or drops and the time period may vary from several days to weeks. Most horses will allow you to medicate reasonably easily however some can be very difficult. In cases where frequent and intensive treatment is required or the horse is un-able to be medicated, a sub-palpebral lavage system may be used. This is an indwelling catheter placed through the eyelids allowing medication to be given without manipulating the eye. A general anesthetic is required for placement.
During treatment your horse should be kept away from bright lights/sunlight. This can be achieved through stabilization or by wearing a fly veil with a patch over the affected eye. Be extra careful around your horse during the injury period as if vision is impaired they may be nervous and spooky.
