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Dog cataracts

May 1st, 2012, 11:06 PM
I have two small breed dogs. Both female. One is a Bichon and the other is a Maltipoo. Both dogs have developed what appears to be cataracts in one eye they both developed them within a couple of weeks of each other. The dogs are 4 and 5 years old respectively. I took them to our vet but her diagnosis was inconclusive. We tried the prescribed eye drops to little or no success. Lately I have noticed the the cateracts appear to contract and dialate with the pupils according to the brightness of the environment. Outside on a sunny day they are vurtually undetectabe and inside in dim light they are quite large. My question to any who may know is; is this indicitve of cateracts. I have never heard of a cataract contracting and dialating before. If not, does anyone know what other conditions may be associated with these symptoms. Any help is greatly appreciated. :sick:

May 2nd, 2012, 08:15 AM
Welcome to the board, dkelly62451.

When eyes react to bright light, the pupil contracts to block some of the light. When it's dimmer, the pupil gets larger to let in more light. The size of the pupil is controlled by the iris, which is the colored part of the eye.

Cataracts form in the lens or the lens capsule, both of which are located behind the iris. So when the iris is expanded (pupil is small) it hides the cataract. When the iris is pulled back (pupil is large) more of the cataract is visible. So what you're seeing is consistent with the presence of cataracts.

We also have a dog, Cole, with a unilateral cataract. He's had it since birth, though--it developed due to a malformed lens in that eye. His two eyes look noticeably different in dim light when the pupil is large and the eye catches lamplight. We found a veterinary ophthalmologist who has been a font of information. I highly recommend you see if there is one in your area--they might have further suggestions for treatment and will be able to tell if the cataracts are likely to progress. The initial evaluation only cost $103 and Cole's followup annual exams are only $50, so the specialist isn't that much more expensive than a regular office visit to our regular vet...

May 2nd, 2012, 11:51 AM
Thank you hazelrunpack,

This is very good info and I will follow up immediately, and thanks for the welcome.