FIVE REASONS NIGHT VISION GETS WORSE AS YOU AGE
Lens changes — As we age, the lens — the clear disk behind the iris — becomes more rigid, and for many also becomes less transparent. These factors reduce the amount of light reaching receptors in the retina at the back of the eye. Left untreated, cataracts can develop and may lead not only to worsening night vision, but to blindness.
Pupil changes — The pupil becomes smaller as we age because the iris, the muscles that control the size of the pupil by adjusting to changes in light become weaker. They also don’t react as quickly as they used to. Smaller pupils mean less light passing through to the retina.
Fewer rods — Rods in the retina detect differences in light and dark. Researchers have discovered that the number of rods significantly decreases as we age. With fewer rods, there are fewer signals transmitted to the optic nerve and brain, decreasing vision at night or in low-light situations. As many as a third of the rods are lost as we age.
Blockages in Bruch’s membrane — Bruch’s (pronounced like “brooks”) membrane sits between the retina and the blood vessels that feed the retina. Just as cholesterol builds up and block arteries, it also builds up in Bruch’s membrane. This prevents nutrients from passing through to the rods, resulting in significantly less light sensitivity.
Reduced dark adaptation — Although fewer rods contribute to a reduced ability to adapt to light changes, the pigment rhodospin eventually stops regenerating as we age. This pigment gives the rods their sensitivity to light. Even if there is little loss of rods, the amount of rhodospin eventually drops significantly. Without adequate rhodospin, the eye can’t make quick adjustments when lighting conditions change.
FOUR TREATMENT OPTIONS
Increase light — In and around the home, increase light sources. During the day, open blinds and curtains to allow in more natural light. Use brighter light bulbs as well, especially for lights used primarily at night. Also place night lights in key areas such as hallways or paths from the bedroom to the bathroom. If you go outside at night, include brighter lights in your yard.
Cataract surgery — For those suffering from poor night vision due to lens changes, cataract surgery might by the solution. Over 90% of patients undergoing cataract surgery have improvement in vision overall, but with significant improvement in night vision.
Diet — Vitamin A and lutein are key nutrients for eye health, particularly in relation to night vision. Eating a diet packed with vegetables and fruit while reducing fatty and high cholesterol foods will provide adequate amounts of nutrients necessary for good vision. These nutrients are also helpful for those with macular degeneration. Taking supplements is advised as high doses of vitamin A has several health risks, including increased risk of osteoporosis and fractures, both of which are already concerns for older adults.
Learn to live with night vision — Many older adults find that they must simply accept reduced night vision. This may mean giving up driving at night. Adjust activities and outings to occur during daylight or arrange other modes of transportation.
PARTING WORDS
If you are struggling with night vision or any other eye or vision problem, call the doctors at Silverstein Eye Centers today at 816-358-3600. We look forward to helping you maintain your eye health or to address any problems you may be experiencing.