I often see the words “check eye- red and swollen” on my schedule. I never know what I am going to find when I walk into the exam room and see the pet that has that gleaming look in its eye, and a red and swollen appearance to boot! My first thought is always “Good job mom/dad for getting this checked ASAP”. A red eye can be an emergency. It can have many different underlying etiologies and can be very serious. Sometimes the cause is not too concerning but others can be vision-threatening. Unfortunately it is impossible to tell without evaluating the eye and doing some simple tests. Treatment can vary tremendously depending on the cause of the red eye.
One potential cause of red eye can be a simple allergic conjunctivitis which is (usually) not serious. But now let’s swing to the opposite end of the spectrum. It could also be an indication of a serious condition called glaucoma, where pressures inside of the eye rise so high that the pet could feel like it has a constant migraine headache. Ouch!! How can we tell what’s going on?
The first step is performing a thorough ophthalmic exam to evaluate eye shape and position, squinting, and discharge. Next we will examine the eyelids, conjunctiva, and the cornea. Then we look deep into the eyes. This is always fun as I wonder what secrets I may discover. Will I find out where the dog bones have been buried or why kitty REALLY scratched up the couch? They say the eyes are the windows to the soul. Well, we don’t really see those things, but we certainly can see if a cataract is developing or if the lens appears to be in the correct position. Finally, we examine the back of the eye, which is called the retina.
We often recommend tests to help us determine the cause of the red eye. A common test (and a very important one in my opinion) is called tonometry. We use a device to determine the pressure inside of the eye and, in turn, can diagnose glaucoma if the pressure is elevated. We may also recommend checking tear production and staining the eye for corneal lesions as both conditions can also cause a red and swollen eye! Our recommendations for treatment are based on our findings and can vary greatly depending on what we find.
Hopefully this article has helped our wonderful pet owners realize a few things. First, a red eye can have many different causes. A prompt ophthalmic exam is of utmost importance and is essential to obtaining a diagnosis. Second, we often require additional testing to help aid us in the diagnosis. Lastly, our treatment recommendations will be based on our findings. So it is vital to see the pet in order to allow us to make the best recommendations for your best friend.
Dr. Candace Auten
Formerly of Camp McDonald Animal Hosptial, Mount Prospect, IL