Sight to Behold
Drivers should be diligent about protecting their vision
By LaNeta Crighton
The sun is down, rush hour is over, and the only traffic on the road is the occasional stray car that pops over the horizon. For some reason, the lights seem extra bright tonight. You rub your eyes and blink, but it’s still hard to focus. You just passed your DOT vision screening, so there can’t be a problem with your eyes. Or can there?
Drivers are required to have vision correctable to 20/40 in both eyes, a field of vision of at least 70 degrees and the ability to recognize the green, amber and red colors of traffic signals. But drivers should think beyond getting a passing grade, and take note of minor vision changes or eye irritation.
The aging eye
If you think your eyesight is not what it once was, you’re probably right. Changes in the eye due to aging start in our 20s, but may not be noticeable until much later. The lens of the eye, which changes shape as we focus on objects at different distances, loses flexibility over time. As a result, peripheral vision decreases. Cataracts, which cause the normally clear lens to become cloudy, also develop as we get older.
“Like gray hair and wrinkles, everyone eventually gets cataracts,” says Stephen Wolchok, M.D., a Jacksonville, Fla., ophthalmologist.
Cataracts aren’t always severe enough to require surgery, but they can have a big effect on driving — particularly at night. Poor night vision is a common early symptom. A person developing cataracts usually sees halos around oncoming headlights. Other objects look dull or blurred. Ghosting or double vision sometimes occurs, and depth perception may be affected. During the day, eyes may be sensitive to sunlight or other bright light.
Treatment is offered based on an individual’s symptoms, not the size of the cataract.
“If cataracts are very disabling, and the patient is having difficulty driving, we sometimes do surgery on even very small cataracts,” says Dr. Wolchok.
Corrective lenses implanted during cataract surgery sometimes eliminate the need for glasses.
Shielding eyes from damaging ultraviolet (UV) rays can slow the development of cataracts, so it’s important to be prepared when you face the sun. Southern states have one to one-and-a-half times more UV rays than northern states, and no matter where you are, exposure is 10 times greater at noon than in the three hours before or after noon.
“Wearing sunglasses protects the eyes and slows the aging process,” says Charles McCormick, M.D., an ophthalmologist at The Indiana Eye Clinic in Indianapolis.
Sunglasses that are polarized and block both UVA and UVB rays offer the best protection, and will keep you from squinting.
But even sunglasses can’t screen out irritants like air conditioning, pollution, wind and cigarette smoke. All can lead to uncomfortable drying of the eyes. Dry eye syndrome can affect vision, and susceptibility increases with age. Dr. McCormick recommends using over-the-counter artificial tear solutions to moisturize and soothe eyes. If dryness continues or worsens, schedule an eye exam.
Eyes and health
Long-term diabetes can lead to retinopathy (damage to blood vessels in the retina). Even diabetic drivers whose blood sugar readings fall within DOT guidelines can experience vision problems related to the disease. Since symptoms may not appear until severe damage has occurred, routine eye exams are vital. Diabetic retinopathy is the top cause of blindness among working-age Americans. However, if it is discovered in its early stages steps can be taken to reduce damage and prevent blindness.
Other health conditions, such as high blood pressure, can also lead to vision problems. A good diet and regular exercise will lessen the risk of many health issues. Stay healthy and you have a better chance of staying focused.