Signs & Symptoms of Scratched Cornea in Dogs

It's easy for a dog to scratch his cornea. The thin tissue that covers the eye is susceptible to nicks or dings from external factors -- an encounter with a cat or sand, for example -- or internal disorders such as hypothyroidism or an ingrown eyelash. If the scratch develops into an ulcer, there is a loss of epithelium on the cornea. Since a scratched cornea can quickly develop into a deeper ulcer, early recognition and diagnosis of a scratched cornea are important. Always consult an experienced veterinarian regarding the health and treatment of your pet.

  1. Squinting or Blinking

    • Scratched corneas can be very painful for animals, just as they can be for humans. Initial symptoms of a scratched cornea are frequent blinking, squinting or keeping the eye shut outright in an attempt to ease the pain. Excessive tear production or discharge from the eye may lead to dark staining of the fur under the eye. A dog may attempt to pull his head in the direction opposite the affected eye area, as if he is trying to escape the pain.

    Visual Inspection

    • While dog eye ulcers are difficult to detect with the naked eye, a scratched cornea can often lead to visible cloudiness in the eye, either as a single white spot or as several small white spots. Alternatively, the cornea may have an opaque, gray-blue spot on it. Another indicator is pupil size: An eye that is in pain will typically have a very small pupil caused by spasms, according to veterinary ophthalmologist Dr. Bruce Silverman. Compare the suspected eye's pupil size with the size of the non-affected pupil. The white area of the dog's eye may be red, and the third eyelid -- that small portion of skin covering the inner part of the eye -- may be visible.

    Lethargy and Diminished Appetite

    • A dog in any kind of pain tends to be lethargic and stay in his bed, according to WebMD. If a corneal scratch is causing pain, the dog may sleep excessively and avoid activity. He may not want to go for his normal walk, and his appetite may be suppressed.

    Physical Evidence

    • There may be evidence of trauma to the dog's face, such as blood or cuts in the fur, which, when combined with other symptoms such as squinting, may lead you to believe that the dog has scratched his cornea from an encounter with a bush or thorn. Furthermore, the dog may paw at or rub the affected eye on the bed, carpet or sofa in an attempt to alleviate the pain.