In our first three blogs on pet eye health, we took a look at some of the most common conditions that affect the eye health of dogs and cats, such as conjunctivitis, corneal ulcers and cataracts. In this blog, we look at one of the few eye conditions that is a true veterinary emergency--glaucoma.
Glaucoma is characterized by high pressure inside of the eye. The high pressure occurs when, for various reasons, the drainage of the fluid inside the eye is prevented. In some cases (and these are the emergency cases), the pressure is so high that it jeopardizes the health of the eye. Glaucoma can result in permanent loss of vision through the progressive death of cells in the retina and optic nerve.
As is with cataracts, the cause of glaucoma can be primary or secondary.
- Primary causes of glaucoma are common in purebred dogs, because they tend to be breed related or hereditary. Primary glaucoma can occur in cats, but it is rare.
- Secondary glaucoma is caused by disease processes that lead to increased ocular pressure, such as lens luxation, uveitis, cancer and trauma. Secondary glaucoma often occurs in only one eye.
Symptoms of sudden onset (or acute) glaucoma are often easy to see. Because acute glaucoma is extremely painful, you may see signs of pain in your pet. Pawing at the eye, declining food and depression are common. You may notice that one of your pet’s eyes looks large, and it may have a blueish tint due to swelling of the cornea. The whites of the eye may be bloodshot and the affected eye may have a dilated pupil.
Acute glaucoma is an emergency and should be treated as soon as possible. The sooner the high pressure inside the eye can be relieved, the lesser the chance for vision loss in the eye.
Your veterinarian may be able to diagnose glaucoma if he or she has the right equipment. The pressure inside the eye can be measured easily and painlessly by using a special tool to tap on the cornea. If the pressure is consistently high over a number of readings, chances are good that glaucoma is the cause.
The goal of treatment for glaucoma is the quick reduction of pressure inside the eye, in the hopes that vision can be protected. Topical eye drops as well as oral medication are used to bring pressure down to a normal range and keep it there. Severe cases, however, may require surgery or even removal of the effected eye. If the glaucoma is not controllable, removal of the eye (a surgical procedure that Petplan pet insurance has paid claims for) is the best way to alleviate pain. Although it sounds severe, pets feel so much better after this salvage procedure.