What is glaucoma? Glaucoma in dogs results from increased fluid pressure within the eye, which damages the retina. The eye pressure inside an eye with advanced glaucoma causes it to bulge. Less than ten percent of dogs with primary glaucoma that receive medical treatment have vision at the end of the first year. By the time owners notice the problem, it is almost always too late to save the dogs vision. Dog glaucoma first appears in one eye and then spreads to the other eye. It is a common eye disease in dogs.
Canine glaucoma strikes one in every 200 dogs in the United States and is a leading cause of blindness in dogs.
There are three general causes of glaucoma in dogs:
Primary glaucoma accounts for most cases and appears when the dog is four to eight years of age. It is linked to specific breeds.
Secondary glaucoma is caused by another eye condition such as lens luxation, inflammation, injury, tumor, previous surgery or infection.
Congenital glaucoma is a birth defect that causes the eye to develop improperly in puppies. This is a rare condition.
Breeds that are at risk are:
Bouvier des Flandres
Miniature and Toy Poodles
Petit Basset Griffon Vendeen
Retrievers (Golden, flat coated)
Terriers (Sealyham, Smooth Fox, Standard Manchester, Welsh, Wire Fox)
Signs of Glaucoma include:
Glassiness to eye
Redness in the white part of the eye
Cloudiness of the eye
Weeping or excessive tearing
Sensitivity to light
Green or yellow eye discharge
Bluish cast to eye
Desire for excessive sleeping
Behavior indicating vision impairment such as bumping into things
Enlarged and bulging eyeball – occurs in late stage
Any of the above symptoms in one or both eyes can indicate glaucoma.
A dog with primary glaucoma will slowly go blind. Treatment will slow the disease, but treatment options will not cure it. Late diagnosis is one reason dogs with glaucoma lose their sight quickly.
In the normal eye, fluid is continually produced to keep the eyeball firm; any excess fluid is drained. A blockage to its outflow or an increase in the fluid dangerously raises the pressure in the eyeball. The pressure inside the eye with advanced glaucoma causes it to bulge.
The aqueous humor is a nourishing fluid that normally maintains appropriate pressure, which gives the eye its shape and firmness. The fluid produced behind the iris by filtering blood, flows through the pupil and then re-enters the bloodstream. A build up of fluid puts too much pressure on the eyeball. This damage eye tissue, which causes pain, headache and complete or partial blindness in dogs with glaucoma.
Eye removal is the only way to prevent pain, but most dog owners opt not to remove the eye for cosmetic reasons.
Medications such as epinephrine, pilocarpine and synthetic epinephrine-like drops reduce fluid production in the eye.
The treatment for glaucoma involves improving the flow of fluid from the eyeball, decreasing the fluid volume, and reducing the amount of fluid formed by using oral and intravenous medication.
Prevention includes diagnosing glaucoma before its signs are present. To make a diagnosis,measurement of intraocular pressure and inspection of the interior of the eyes is needed. This should be done during the dogs regular yearly examination. We should take the time to learn about glaucoma and the signs and symptoms of the disease so the dog can get early treatment.
If left untreated, chronic glaucoma may result in increased size of the eye and protrusion. It may be managed for a time with drops and medications.