Eye-rubbing may indicate glaucoma

Penny is a 10-year-old cocker spaniel who has had her share of ear problems.

Pat isn't sure whether Penny is having a problem now, but she is noticing a new behavior. Penny is rubbing the left side of her face on the carpet, and she's started to do it more frequently.

Pat thinks Penny is specifically rubbing her left eye. There is some redness around the eye and the eyeball. Pat first thought Penny may have gotten something on her face, but she no longer believes that to be the case.

Well, Pat, there is a problem. That's the easy part. Determining the underlying problem is the not-so-easy part.

I am going to assume that Penny is indeed rubbing her eye and not some other area close to it. So we can conclude there must be something irritating Penny's left eye or the lids around it.

There are many possibilities that can cause eye irritation. Penny may have damaged the corneal layer of the eye, causing significant discomfort. The cornea is a very specialized layer of clear cells that covers the colored portion of the eye, the iris. The pupil is behind the cornea. Damage to the cornea can come from contact with anything that can score or puncture the tissue. Foreign material in the eye is but one possibility.

Penny may have developed a conjunctivitis or inflammation of the conjunctiva. The conjunctiva is a very thin layer of tissue that covers the inside of the eyelids and eyeball itself. It can become inflamed from an allergic response or a bacterial infection or a combination of both. This list can go on, but there is one possible cause that is potentially very serious and could lead to blindness. Cocker spaniels are a high-incidence breed for this disease.

Penny may have glaucoma. Glaucoma occurs because of increased pressure within the eye. The eye is actually filled with a viscous fluid that supports its round structure. The fluid is maintained at a constant pressure through constant production within the eye and constant drainage out of the eye. If this system is disturbed, usually affecting the drainage, the pressure within the eye can increase; if left untreated, this increased pressure will destroy the retina at the back of the eye, causing blindness.

This process can be extremely painful and is considered an emergency.

In humans with acute glaucoma, the increase in pressure and corresponding discomfort can be communicated to the doctor and therapy immediately performed. Pets do not usually do this, at least early on, although Penny may have done so with her rubbing behavior.

Penny needs immediate veterinary attention. If she does have glaucoma and there is still sight present, we may be able to save her eye. If not, she will need to have treatment done to alleviate her pain. This might include removal of her nonfunctioning eye.