How does sunlight damage the eye

UV Light Contributes To Eye Disease



Does lingering in the summer sun increase your risk of developing chronic eye disease?

Yes. Studies have shown that permanent damage to the eyes can result from
prolonged sun exposure without adequate protection.

How does sunlight damage the eye?

Ultraviolet (UV) light is the component of sunlight most responsible for eye damage.
Excessive exposure to UV light, especially from light reflected off sand, snow, or
pavement, can produce a burn on the surface of the eye. Like a sunburn on the skin,
eye surface burns are painful but usually temporary.

According to Michael F. Marmor, MD, Professor of Ophthalmology at Stanford
University Medical Center, “Of greater concern than the acute damage caused by a
day in the sun is the cumulative damage of repeated UV exposure that may contribute to chronic eye disease.”

Long-term exposure of the eye to UV light affects not only its surface (cornea and
conjunctiva) but also its internal structures (lens and retina). UV exposure is a risk
factor in the development of pterygium, a fleshy growth that invades the corner of the
eye; cataracts, or clouding of the lens; and macular degeneration, or breakdown of
the macula.

Who is most at risk for eye damage by UV light?

A person’s lifestyle appears to be the most important factor in determining who will
be most affected. Those who spend considerable time in the sun or those who live at
high elevation or near the equator, where UV levels are increased, are at the greatest
risk.

Medical circumstances can also predispose a person to eye damage from UV.
Persons taking photosensitizing drugs, such as psoralens (used to treat psoriasis),
tetracycline, doxycycline, allopurinol, or phothiazine, can be more sensitive to light.

During cataract surgery, patients have the natural lens of their eye removed and
replaced with a synthetic lens. For this reason, cataract surgery patients can also be
especially vulnerable to the effect of sun on their eyes.

How can you protect your eyes from UV damage?

You can greatly reduce your eyes’ exposure by donning sunglasses and a
wide-brimmed hat. The American Academy of Ophthalmology recommends that
sunglasses screen out 99 to 100 percent of UV light (both UV-A and UV-B).
Sunglasses have the added benefit of shielding the eyelids from sun exposure. A
wide-brimmed hat prevents light from entering the eyes from above.