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Age-related Changes in the Eye
Visual impairment is the most common sensory problem
of older adults. About 95% of individuals age 65 and older report wearing
glassing or needing glasses to improve their vision. However, the effectiveness
of glasses decreases with age. Among those over age 85, only 45% report
that their glasses corrected all their visual problems and 12% are legally
blind. Older adults should have vision checkups every two years if they
wear glasses, every five years if they don't. Those with a family history
of eye disorders, diabetes or a diagnosed vision disorder such as glaucoma
or cataracts should get more frequent checkups.
Beginning in your 30s there is a decrease in the ability of your eyes
to produce tears. Dry eyes can be made more comfortably by using "artificial
tears" solutions. As you age, the pupil decreases in size, by age
60 it is about 1/3 the size it was when you were 20. The pupil may respond
to darkness or bright lights by changing in size more slowly. The lens
of the eye becomes yellowed, more rigid, and slightly cloudy. The iris--colored
part of the eye- becomes more rigid over time. Some of the major normal
aging changes in the eye that affect vision include the following:
- Corneal Flattening
In the aging eye the corneal surface flattens, admitting less light
into the eyeball. This change reduces the transmitted light into the
elderly eye by one third.
- Lens Transparency
The transparency of the lens actually diminishes with aging which
weakens available light to receive colors with short wavelengths such
as blue and violet. When new lens fibers naturally multiply at the
edge of the lens, older fibers move to the center to create a dense
center of the lens. Over time, the lens accumulates yellow substances
which filter out the blue part of the color spectrum. Blue actually
appears more green. Warmer colors like reds and oranges, seem stronger
in comparison.
- Less Efficient Retina
The most sensitive part of the retina gradually functions less well
with age due to decreased blood supply and the cumulative effects
of radiation damage. The result is decreased spatial discrimination,
black and white contrast, and flicker sensitivity. You become less
able to tolerate glare and have more trouble adapting to darkness
or bright light.
- Reduced Lens Elasticity
Over time the lens of the becomes less elastic which diminishes the
focusing power of the eye and causes a decline in visual acuity. This
changes is usually first noticed around age 40 and is called presbyopia.
As presbyopia becomes more pronounced, people hold reading materials
further away from their eyes. Some get headaches or "tired eyes"
while reading or doing other close work. By age 55, most people require
glasses for reading at least part of the time. Those who already wear
glasses may need bifocals. Fortunately, only 5% become unable to read
and about 20% have enough visual impairment to prevent driving.

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