There are many causes of sore eyes, one of which is a corneal ulcer.
The cornea is a transparent structure that acts like the “windscreen” of the eye; it is subject to damage from the outside world as well as damage from diseases inside the eye.
A corneal ulcer is due to damage to the outside layers of the cornea.
Corneal ulcers can be caused by many factors. The common causes include
• Physical trauma e.g. a scratch from another pet
• Chemical trauma e.g. shampoo in the eye
• A foreign body e.g. hair constantly rubbing the cornea, dirt, sand, grass seeds etc.
• Inadequate tear production
• Eyelid disorders that prevent distribution of tears across the cornea
• Infections e.g. In cats corneal ulcers are usually associated with the upper respiratory viral infection (herpes virus).
Signs of corneal ulceration include redness to the eye, an opaque (hazy) area on the cornea , squinting, a watery eye, varying degrees of pain ( deep ulcers are often not painful even though they are really serious and can result in a loss of the eye) and pus discharge.
Treatment varies with the cause and depth of the ulcer. It usually involves pain relief, oral and topical medications to help corneal healing and an e-collar to prevent further self-trauma. Any primary problems found (e.g. hair rubbing the eye, inadequate tear production) also need to be addressed.
Most eye ulcers are simple and heal quickly (within 1-2 weeks) those that are slower are considered serious and may need additional procedures (e.g. grid keratotomy). Slow healing ulcers are called “indolent” and are more common in certain breeds either due to their eye conformation (e.g. brachycephalic breeds) or due a dystrophy of the cornea (e.g. Boxers, Boston terriers). Deep ulcers may require surgery by a specialist to save the eye.
Frequent (3-7 days) veterinary re-examination of the eye should be performed until the corneal ulcer is healed. You must carefully observe healing- if you think the eye isn’t improving, is getting worse (more red/ blue, more painful, more discharge) then please get it re-examined sooner than the next planned recheck as corneal ulcers can progress very quickly!