Why do I need an eye exam?
Many physical changes come with aging, including changes in vision. This is why it is important to have a complete examination by an eye doctor at least every other year after age 40 and every year after age 65. People with certain risk factors (such as a family history of eye disease or diabetes) should have a comprehensive eye exam every year regardless of age.
Even if your vision seems good, you should still have regular eye examinations because some conditions are asymptomatic and affect the eyes very slowly. By the time you notice any changes in your vision, it may be too late to repair the damage. Fortunately, early treatment can stop most of the vision loss caused by the following conditions most commonly seen in seniors.
The eye is often compared to a camera. The front of the eye contains a lens that focuses images on the inside of the back of the eye. This area inside the eye is covered with special nerve cells. Some of these cells "react to light" while others "carry the picture" to the brain. When excessive pressure builds up in the eye, it damages the cells that carry the picture. This is called glaucoma.
Glaucoma is usually painless and causes no noticeable symptoms. Because there are many, many nerve cells in the back of the eye and they are damaged only a few at a time, it can take years before someone with glaucoma notices any changes in vision. An eye doctor can detect glaucoma much earlier, however.
Because vision loss due to glaucoma is permanent, early detection of the condition is extremely important. Although glaucoma cannot be cured, there are medications that can lower the pressure inside the eye and reduce the chance of further damage. By getting the right treatment early, vision loss from glaucoma can nearly always be prevented.
The nerve cells in the back of the eye (the retina) are very close together in the area where the eye focuses the images that we see. This part of the retina is called the macula. As people age, the macula tends to change in ways that cause a gradual loss of sharp vision. Sometimes, the macula actually begins to break down, and occasionally new blood vessels can grow where they do not belong.
This condition of abnormal macula breakdown and/or new blood vessel formation is called age-related macular degeneration. You might have this condition if you notice that:
- The ability to see fine details when one is looking directly at an object, no matter how close or far away it is, starts to decline
- Vision changes so that straight lines look wavy or broken
- Dark spots, lines, or shadows appear in your field of view
There is no cure for macular degeneration, but several possible treatments can slow vision loss and help a person keep useful vision for many years if they are started early enough.
Diabetic eye disease
As we age, our risk for developing diabetes increases. One of the major effects of diabetes is to make blood vessels "leaky."
The retina (the layer of nerve cells that lines the inside of the back of the eye) has a layer of blood vessels. When diabetes makes these blood vessels leak, fluid can build up in the retina. This can blur vision. Eventually, the blood vessels can break open and bleed, and new blood vessels will grow to take their place. All of this can cause permanent loss of vision.
The best way for someone with diabetes to prevent the loss of vision is to follow the doctor’s advice about control of blood sugar, blood pressure, diet, exercise and medication, and to schedule an eye examination at least once a year.
The eye contains a lens that focuses light so we can see. Sometimes this lens turns cloudy, and this is called a cataract. Most cataracts are a normal result of aging, although they can be caused by injury or other medical conditions. The only treatment is to surgically remove the clouded lens.
Cataract surgery is usually performed with local anesthesia. That is, the patient is awake but does not feel the procedure. The surgeon will make a small opening in the front of the eye so the cloudy lens can be removed and replaced by a new clear plastic lens.
Almost 2 million people per year in the United States have cataract surgery and receive an intraocular lens. It is the most frequently performed operation in the world, and also one of the most successful.