Q: We have noticed that our 11-year-old Cavalier King Charles Spaniel’s vision seems to be getting increasingly worse. She has had something the vet calls KCS or dry eye for several years now and for which she gets daily ointment applied to the eyes to increase her tear production. Her eyes have also darkened but there has been no mention of cataracts or anything else that might compromise her vision. Are there any surgical procedures that might be considered to improve her vision? She seems perfectly content, but we do notice her bumping into a few things at times especially when she is out of familiar surroundings. Could the KCS be affecting her sight? Could something else be going on? Thanks.
A: Keratoconjunctivitis sicca or KCS is a condition most commonly found in brachycephalic or short-faced breeds of dogs, among which Cavaliers are often represented. Also known as dry eye, early detection is key to preventing secondary complications such as corneal ulcers and even loss of vision. In this condition, the normal tear glands have reduced or no tear production, which causes the dry eye to be irritated and infected wherein the dog rubs the eyes incessantly or squints, if not closing their eyes. Any dog with chronic eye irritation and conjunctivitis should be evaluated for tear production with something called a Schirmer Tear Test as well as possibly testing for glaucoma and looking for eyelid masses or other possible issues.
Dogs with KCS also often develop corneal pigmentation which appears as brown pigment on the cornea also affecting vision. This may be what your dog is experiencing. Sadly, there is not much that can be done, including surgery, to reverse this other than maintaining the status quo with proper moisture application to the eye with medication like you are using, most likely cyclosporine. This drug helps stimulate some tear production and adds moisture itself. If your veterinarian had also noted changes in the lens, cataracts can be effectively treated with surgery whereas lenticular sclerosis is not. Speak with your veterinarian about a possible referral to a board-certified veterinary ophthalmologist to make sure nothing else could be causing issues and for a more specialized assessment, which will give you more definitive answers.
Dr. John de Jong owns and operates the Boston Mobile Veterinary Clinic. He can be reached at 781-899-9994.
