How does aging affect vision?

DEAR DOCTOR K:

What changes can I expect to my eyes and vision as I get older?

DEAR READER:

In most of us, nearly every part of our eyes shows changes caused by aging. As eyes age, eyelid muscles weaken and skin becomes thinner and looser. This can cause the upper lid to droop or the lower lid to sag.

Tear production also drops off, and the oily film that tears provide decreases. These changes can lead to a buildup of sticky mucus, or they can dry the cornea, causing irritation or an uncomfortable, gritty sensation.

Your sclera, the eye’s white outer surface, may yellow from fat deposits. Calcium deposits in the sclera can produce patches of grayish translucency, and the cornea can develop an opaque white ring around its edge.

The lens, which focuses light rays onto your retina, hardens and loses its elasticity over time. This causes presbyopia, or difficulty focusing on near objects. Aging can cause your lens to darken, grow opaque and thicken, causing nearsightedness. Your night vision may also worsen.

A clouding of the lens is called a cataract. It may go unnoticed until the cloudiness blocks your central line of sight and impairs vision.

Over time, fluid that nourishes your eyes may back up, leading to increased pressure inside the eye that damages the optic nerve. This is called glaucoma, and it can silently impair sight before symptoms develop.

Your retina sends your brain messages describing the objects you see. The aging retina thins and may grow less sensitive. The macula, a small part of the retina that provides sharp, central vision, is especially prone to deterioration. Age-related macular degeneration can steal a person’s central vision.

We have more information on age-related changes to vision in our Special Health Report, “The Aging Eye: Preventing and treating eye disease.” You can learn more about it here.

Regular eye exams are the cornerstone of visual health as you age. Don’t wait until your vision deteriorates to have an eye exam, as often only an exam can detect eye disease in its earliest stages.

While an eye exam is the best way to catch eye disease early, there also are other ways. I discovered one way about a year ago.

When doctors use an ophthalmoscope (the gadget with the light that shines inside your eye), we flip a little wheel that allows us to see deeper and deeper inside the eye. First we see the lens, and then look through the lens to the back of the eye.

I realized I was having more trouble seeing the back of my patients’ eyes, and figured it was because their lenses were getting cloudy. But why would all my patients be getting cataracts? Then I realized there was another possible explanation: I was the one who was getting a cataract.