Canine Eye Diseases

Distichiasis and glaucoma are two of the most common eye diseases in canines. Both of these diseases can be overlooked, leading to potentially serious consequences like blindness in the case of glaucoma. Pay attention to your dog's eye health and talk to your veterinarian if you recognize any of the symptoms.

  1. Diseases

    • Distichiasis is a disease of the eye that results from eye irritation caused by abnormal eyelash growth.

      Glaucoma is characterized as abnormally high pressure within the eye. There are two types of glaucoma: primary and secondary. If your dog has primary glaucoma, she most likely has a problem with the way the eye is draining aqueous fluid. Secondary glaucoma means the glaucoma is caused by some other disorder, typically unrelated to the draining fluid.

    Causes

    • The extra eyelashes that cause distichiasis come from what is called the Meibomian glands. When a dog has distichiasis, two or more hairs grow from these glands and irritate the eyeball and its surrounding tissues.

      Primary glaucoma appears in dogs when the way fluid drains from their eye becomes abnormal. This can be caused by too few drainage holes or ones that aren't working properly. Secondary glaucoma is caused by other factors, including tumors and trauma to the eye.

    Symptoms

    • Symptoms of distichiasis can range from minimal to severe depending on the length of time the eyelashes have been present and their texture. Symptoms of distichiasis include pain in the eye and eyelid, corneal ulcers and increased blinking. You may also see excessive tearing or your dog squinting or holding his eyes closed.

      With glaucoma, you may notice your dog's pupils do not contract as quickly as they should when exposed to light. The pupil may appear slightly larger and there may also be eye redness and irritation.

    Treatment

    • Treatment for distichiasis involves destroying the hair follicles that create the abnormal eyelashes, which keeps the hairs from returning. Cryotherapy is used to freeze the margins of the eye where the eyelashes grow. Surgery and electrolysis are also used to destroy the hair follicle and remove the hair. Simply plucking the eyelashes will not suffice as this does not destroy the follicle and distichiasis can appear again.

      Glaucoma in canines is treated with oral diuretics that help relieve some of the pressure in the eye. Glaucoma that does not respond to medications can only be treated with surgery, which involves implanting a drain to remove excess fluids. Medications are also injected into the eye to kill the cells that produce the fluid.

    At Risk Breeds

    • Dogs that have distichiasis should not be bred, to reduce the chance of passing it down through the blood line. Some breeds in particular appear to be more susceptible to distichiasis like the cocker spaniel, the English Bulldog, golden retriever and poodle. The miniature poodle, Yorkshire terrier, Lhaso Apso and pug are also at-risk breeds for distichiasis.

      Those at particularly high risk for glaucoma are the chow chow, samoyed, great dane and dalmatian. The shih tzu, poodle and Alaskan malamute are also considered high risk breeds for glaucoma.