When pets lose their vision

In the event that a pet loses his vision, there are many steps an owner can take to keep him familiar with his surroundings. Photo: File photo In the event that a pet loses his vision, there are many steps an owner can take to keep him familiar with his surroundings. Photo: File photo

There’s something magical about eyes. Sleek and precise, they seem built of different stuff than the rest of our physical selves—something more deeply connected to the root of who we are. This may be true in more than the poetic sense. Embryologically, the eyes sprout directly from the same clump of cells that go on to form the brain, as if the mind itself insists on peering out from the body that it has been made to inhabit.

Perhaps this is why eye contact feels so immediate and personal—two minds literally seeing one another—and why it can be so distressing when that contact breaks down. Many people are familiar with the signs of aging in their pets’ eyes. Is it cataracts? Does it affect vision? Is blindness next? It’s normal to fear what might happen if you simply can’t see each other anymore.

We are at a disadvantage trying to assess vision in our pets. For obvious reasons, we are unable to sit animals in front of an eye chart to get an accurate read of visual acuity. And, let’s be honest, we’re not going to fit them with prescription eyeglasses even if we could. Veterinarians can tell if a pet is completely blind or not, but we often rely on observations at home to sort out the spectrum between those extremes.

Many older pets develop a benign condition called nuclear sclerosis—a hardening of the lens deep within the eye. Owners first notice a milky look to the pupils, and often worry about cataracts. But this condition is a normal part of aging and rarely causes any serious loss of vision. Unfortunately, at a glance this condition looks very similar to cataracts—your veterinarian can differentiate between the two with the aid of an ophthalmoscope.

Unlike nuclear sclerosis, cataracts are not normal. They are a disease process that clouds up the lens, interfering directly with vision. They can happen on their own or in response to underlying diseases like diabetes. In some cases, cataracts can be removed surgically, although this requires a visit to a specialist (yes, there are animal ophthalmologists, and they are fantastic). In other cases, we may simply choose to monitor them for progression. Unfortunately, there is no medical management known to treat cataracts, no matter what miracle cures you might read about.

There are other disorders that can affect vision, of course. Glaucoma, an increase of pressure within the eye, could permanently blind affected patients within a day. A mysterious condition called SARDS (sudden acquired retinal degeneration syndrome) can cause dogs to go blind all at once for no apparent reason. And even routine eye infections might progress to severe corneal scarring if left untreated. When it comes to eye problems, it’s best to seek veterinary attention at the first sign of trouble, rather than risking serious complications by trying to wait it out.

Some pets are sadly bound to lose their vision regardless of what steps are taken. Although it’s hard at first, I’ve always been amazed by the capacity for animals to meet that challenge with astonishing grace and cheer. It falls to us to make sure their environment is consistent so they can learn the layout and navigate with confidence, and to block off hazards such as stairwells to prevent accidents. Distinct tactile surfaces like throw rugs and carpet runners can provide non-visual cues that help pets get their bearings.

It’s also up to us to communicate with our pets in new ways if eye contact is no longer an option. If you’re anything like me, you already spend a decent amount of time talking and singing to your pets (is that weird?), so it shouldn’t be hard to do that a little more. And never underestimate the power of touch. A guiding hand or a warm hug go a long way toward letting pets know they are safe and secure, even in the dark.

Dr. Mike Fietz is a small-animal veterinarian at Georgetown Veterinary Hospital. He received his veterinary degree from Cornell University in 2003 and has lived in Charlottesville since.