It's easy for your dog to scratch his eye when running about in the undergrowth or roughhousing with the family cat. If your dog is squinting, pawing at his eye or showing any other sign of an injury, take him to your veterinarian as soon as possible. Even a slight scratch of the cornea -- the clear outer layer of the eyeball -- can develop into a corneal ulcer and lead to sight loss.
Scratches, also known as corneal erosions or abrasions, can happen when your dog is darting about in dense or thorny bushes. He can scratch an eye when rubbing his face on the carpet, scratching at a painful ear or from pawing at his eyes. Sometimes, a foreign body, such as a grass seed, is stuck under the eyelid and scrapes the eye. Your dog's eye also can be scratched by another animal. Cat scratches often happen when a new puppy meets the family cat. These injuries are likely to get infected as a cat's claws are loaded with bacteria.
Corneal damage is usually very painful. Your dog may squint or keep the scratched eye closed. You will probably catch him pawing at his eye or trying to alleviate the intense irritation by rubbing his face on the carpet. The affected eye may tear excessively and can become red and inflamed. If the eye becomes infected, there may be a yellowish-green discharge.
What To Do First
If you suspect your dog has scratched his eye, have him examined by your veterinarian straightaway. Don't try to clean the eye or remove a foreign body. Never treat it with any eye medications made for humans. Corticosteriods, found in many eye preparations, shouldn't be used on a corneal injury as there is a danger of the cornea rupturing. While waiting for your appointment, use an Elizabethan collar -- a cone-shaped collar designed to prevent self-trauma -- to stop your dog from pawing at his eye and causing further damage. Alternatively, wrap soft bandages around his front legs to cover his dewclaws.
Diagnosis and the Fluorescein Stain Test
Your veterinarian will examine the dog's eye, and, if needed, remove any foreign body. She will use a fluorescein stain test to evaluate the extent of any damage, as scratches on the clear cornea can be difficult to see. A drop of the stain is placed on the eye. The dye sticks to any damaged areas and shows up as bright green under a fluorescent light.
Treatment and Medication
Corneal scratches usually heal in about three to five days. Your veterinarian will prescribe ophthalmic antibiotic drops or ointment to prevent bacterial infections. To be effective, ointment must be placed in the eye four to six times a day. Your dog also will be given topical atropine for pain relief. Atropine dilates the pupil, so expect your dog to be more sensitive to light. It also has a bitter taste. He may drool if the atropine runs into his throat from the tear duct. He probably will need to wear an Elizabethan collar while the erosion is healing.
Follow-up and Home Monitoring
Your veterinarian will repeat the fluorescein stain test after a couple of days to check that the scratch is healing properly. She may need to do this every one to seven days, depending on the extent of the damage and how well it's healing. If your dog's eye becomes more painful, there's a discharge or you notice anything that doesn't look right, go back to your vet before his next appointment. It's important not to stop the treatment until the tests show the eye has healed.