Cataracts
The most common cause of a cataract is aging.
Cataracts are the third most common reason for vision loss in the elderly. From ages 65–74, 18% of vision loss can be attributed to cataracts. For ages 75–84, cataract-related vision loss rises to 46%.
A cataract is a clouding of the normally clear lens of the eye. As one ages, the loss of lens transparency may be so mild that vision is only slightly affected, or so severe that no shapes or movements are seen, only light and dark shapes. When the lens gets cloudy enough to obstruct vision to any significant degree, surgery may benefit the patient.
Reducing the amount of ultraviolet light exposure by wearing a wide–brim hat and sunglasses may reduce risk for developing a cataract. Once a cataract interferes with vision, the only way to improve eyesight is to have the cataract surgically removed. Glasses or contact lenses may not be able to sharpen vision enough if a cataract is present. Surgical correction should be performed when lifestyle and ability to do daily tasks becomes difficult.
Cataract Symptoms
The typical symptom of cataract formation is a slow, progressive, and painless decrease in vision. Other changes include: blurring of vision; glare, particularly at night; frequent eyeglass prescription change; a decrease in color intensity; a yellowing of images (right: normal vision vs. vision with yellowing); and, in rare cases, double vision.
Treatment
One and a half million people have cataracts removed every year and 95% have a successful result. There are no medications, eye drops, exercises, or glasses that will cause cataracts to disappear or prevent them from forming.
The only treatment for a cataract is to remove the lens and replace it with a plastic intraocular lens. Unlike contact lenses, which must be removed, cleaned, and reinserted, the lens remains in the eye after surgery.
Dr. Higa performs a procedure known as phacoemulsification, or "phaco" for short. With this procedure, numbing eye drops are used to anesthetize the eye, and a small incision is made without the need for stitches. The lens is removed, and a new one is inserted. This surgery is performed on an outpatient basis. Ninety percent of procedures performed achieve at least an eyeglasses corrected vision of 20/40 or better.
Driving and Cataracts
When I drive I get nervous because I don't see so well. What's happening and should I be concerned?
To pass a driver's license test, the current minimum legal vision is 20/40 and more than 70 degrees of visual field or peripheral vision. Passable vision does not take into account the fact that reflexes slow as one gets older. The increased fraction of a second it takes to step on the brakes and maneuver an automobile may make a difference between avoiding an accident and being a part of one.
Elderly drivers should be fitted with a current glasses prescription to maximize vision correction. It is also important to be examined thoroughly and treated for cataract and retinal diseases, such as glaucoma and macular degeneration.