The anatomy of the dog’s eye somewhat matches the eye in humans. The eye organ differs with dogs structurally having a third eyelid, located at the inner curve of the eye near the nose. The parts of the eye (cornea, pupil, anterior chamber, iris, ciliary body, lens, eye muscle, optic nerve, vitrous chamber, retina, and orbital fat) operate the same in the dog as in man.
Harvey, a rambunctious 3-year-old Chihuahua-terrier exhibits eyes that bulge slightly on his face as a normal feature of his anatomy. Our veterinarian assessed our pet’s eyes as part of a normal year examination. Protruding eyes appear as normal anatomy in other dog breeds as well (Such as Pugs, Brussels Griffon, Japanese Chin, Pekingese, Poodles, Shih Tzu, Toy Fox Terrier, and Whippet)
Dog owners may come across conditions related to bulging eyes that are not normal anatomy. A bulging eye may emerge with glaucoma, tumors and abscesses. An emergency problem may occur if one or both eyeballs become dislocated (the eye comes out of its socket).
Evaluating the eye condition associated with bulging or swollen eyes:
1) Glaucoma – Glaucoma in canines corresponds to the disease in man. Fluid normally exchanges between the chambers in the eye and the rest of the body, but in glaucoma, the fluid emerges faster than removal of the liquid. The intraocular pressure escalates and puts stress on the nerve in the eye with possible blindness. The veterinarian uses drugs like mannitol to remove fluid immediately and can perform surgery to decrease fluid production. Otherwise, daily eyedrops like Cosopt (contains two drugs timolol and dorzolamide) increase the flow of the fluid.
2) Tumors – Cancer in the space behind the eye generates a gradual bulge of the eye. Mutant cells produce fast growing cells called cancer. Cancer cells crowd out normal cells and replace the vital structure. Cancers found behind the eye require removal to prevent loss of vision or spread of the cancer.
3) Abscesses – A retrobulbar (behind the eye) abscess produces severe pain. The dog exhibits excessive tearing, squinting, distress on being touched or sensitivity to light. The animal may whine, cry or paw at the eye. Abscesses arise from infections that localize and produce a pocket of pus. Common organisms create abscesses from bacteria like staphylococcus and streptococcus that are common on skin. The dog requires treatment by a veterinarian to drain the abscess and treat the animal with antibiotics.
4) Hematomas – Hematomas or blood clots may develop behind the eyeball due to head injuries. Removing the clot by a veterinarian prevents damage to the eye tissue and the optic nerve.
5) Eyeball out of the socket – Dislocation of an eyeball can occur from dog bites or trauma to the head. An emergency exists if the eyeball dislocates as swelling can arise causing damage to the optic nerve with possible blindness. Rush the dog to the nearest veterinary hospital if this occurs. Covering the eye with a wet cloth prevents damage to the delicate eye tissue until treatment is available.
What can you do for your dog’s eye problem?
By having your canine companion complete a yearly health examination, you can determine if your dog possesses eye disease. Proper treatment improves the overall health of your pet.
Eldredge, D.M., Carlson, L.D., Carlson, D.G. & Giffin, J.M. Dog Owner’s Home Veterinary Handbook. Amazon.com
Dog Owner’s Guide. All About Canine Eyes. Canismajor.com
American Kennel Club. Breeds. Akc.org