April 19, 2006
The most common cause of vision loss in the 60 and over age range is cataracts. A cataract is an area of lost transparency in the crystalline lens of the eye. It is not a disease. It is a natural process that happens to everyone —sometimes at 50, sometimes at "150." It becomes clinically significant when it begins to reduce the patient's vision.
What is a cataract and how does it form? To begin with, let's look at the crystalline lens. It is located directly behind the pupil (the black opening in the iris that allows light and images to enter the eye). The lens is made up of perfectly aligned strands of protein fibers. Without getting into physics, I'll just say that the perfect symmetry of these fibers is what makes it a transparent focusing tissue. Over time, a percentage of these protein molecules break down, disrupting the alignment of the strands; on a significant scale, this is what creates the cataract.
There are some factors that affect the growth rate of cataracts. Exposure to ultraviolet rays from direct sunlight has been shown to increase cataract growth. Cigarette smokers (about one pack plus per day) will on average develop cataracts at an earlier age than non-smokers. Good diet with healthy levels of vitamin C may help slow cataract development.
Cataracts are treated by removal. A generation ago, the entire lens was removed, and thick glasses were used to replace its strong focusing. Then, contact lens fitting was introduced to restore more natural vision . . . and appearance. The most important development for cataract patients was the lens implant. The cataract is removed, keeping its tough outer membrane intact. Then an artificial lens is placed within this membrane capsule. This technique yields the most natural result, and is physically the least traumatic to the eye. It has been refined and refined until it is usually a stitchless procedure. It is performed on an outpatient basis, where you're operated on in the morning and seeing in the afternoon. In addition, a revolutionary new multifocal implant is now available, giving effective reading and distance vision simultaneously. Please ask your doctor about this option.
When should cataracts be removed? One of my least favorite euphemisms that doctors frequently used was "ripe." This suggested that the doctor would "pick" it from the eye when he decided it was ready. These days, rarely will a cataract be so bad that he must remove it (although I indeed have seen a few cataracts that are absolutely opaque). In most instances, the patient and doctor are both involved. When the doctor can no longer improve the vision to a level that allows the patient to do what he or she wants or needs to do, then surgery should be performed.
These days, results are so good and recovery is so rapid that I tell patients that there's just no reason to put up with reduced quality of life caused by cataracts. In fact, if I had to have any medical problem with my eyes, I would undoubtedly wish it to be cataracts.