As an ophthalmologist specializing in retinal disease, I see patients with various age-related eye diseases every day. It often surprises me how patients incorrectly assume that poor vision has to be just part of aging. Though there are several conditions that are more common as we get older, the large majority of people can maintain good vision into their eighties. I enjoy taking the opportunity to explain changes that are normal and those that can be indicative of a problem.
Lens changes are the most prevalent age-related eye development. Presbyopia, or limitation of our ability to focus at a normal reading distance, is due to hardening of the lens proteins. In many people, this becomes noticeable in our forties and is treatable with reading glasses. Cataracts begin to form in our fifties when lens protein changes cause a yellowish discoloration of the lens. Blurred vision or uncomfortable glare from bright lights can develop. Cataracts are usually mild at first, and for many years an updated glasses or contacts prescription may be the only required intervention. If cataracts progress to the point that quality of life is affected and glasses don't help, your eyecare provider can discuss cataract surgery to improve vision.
Structures in the front chamber of the eye are crucial to regulating the pressure of the fluid in the eye. Glaucoma develops when the pressure becomes elevated and damages the nerve that sends visual signals to the brain. Patients of African-American descent are at twice the risk for glaucoma. Eyecare providers routinely check the eye pressure to screen for this problem.
Behind the lens, a gel called the vitreous fills the back chamber of the eye. The vitreous takes on a watery, less viscous consistency over time and ultimately will separate from the retina in most people by age seventy. Separation of the vitreous can cause new visual symptoms such as floaters or flashing lights. These symptoms should prompt patients to contact their eye doctor urgently to seek evaluation for a retinal tear or the beginning of a retinal detachment.
Finally, the retina, the light-sensing nerve layer in the back of the eye, changes over time as well. Slower adaptation to a dark environment and a subtle decrease in retinal sensitivity are normal. Roughly half of patients over 75 will develop small deposits called drusen under the retina. The presence of drusen means an increased risk of developing macular degeneration. 30% of people over 70 develop at least some degree of macular degeneration, with 10% of those patients going on to noticeable vision loss by age 80. If findings of macular degeneration are noted on an eye exam, then patients are often referred to a specialist such as myself for mitigation of vision loss. Eating a healthy diet rich in leafy green vegetables and avoiding smoking minimize your risk of vision loss from macular degeneration.
Screening exams are important to identify potential vision problems as we age. The American Academy of Ophthalmology recommends that healthy patients age 65 or older get an eye exam every one to two years, or more frequently if needed. Patients with diabetes or other systemic medical conditions may need eye exams more frequently to monitor for problems.