Cataracts are a condition in which a cloudy or milky substance covers the lens of the eye, blurring or blocking vision. They are very common in the United States, particularly in people over the age of 50; one recent study found that over 24 million people suffered from cataracts in 2010 alone. According to the American Academy of Ophthalmology, more than half of all Americans will develop cataracts by the age of 80. Furthermore, cataracts are a progressive condition and will only worsen over time without proper treatment.
The most common symptom of cataracts is a slow clouding of the eye that ultimately blurs or blocks vision. While they are rarely painful, they do cause a decrease in visual acuity, glares in the visual field, a dulling of colors, and changes in your prescription glasses needs.
If your doctor suspects that you may be suffering from cataracts, they will generally take a detailed medical history, including your family history and conduct one or more of the following more advanced tests: a visual acuity test, a slit-lamp examination, or a retinal exam. A visual acuity test uses a fixed chart with rows of increasingly more difficult-to-see letters that patients attempt to read with one eye. This test allows your physician to gauge the overall strength of your vision and determine how severely cataracts are affecting your ability to see clearly.
A slit-lamp examination is a physical examination of the eye that uses a slit–a small line of intense light–projected from a specialized microscope to illuminate the structures of your eye in tiny sections. This allows your physician to more thoroughly examine the eye and pick up on small changes or abnormalities that might be missed with a wider range of view. Finally, a retinal exam requires your physician to place drops in your eye, dilating the pupil so that they can get a clear view of the retina at the back of your eye. With this newly clear line of sight, they use an ophthalmoscope to examine the lens and retina for signs of cataract development.
If your physician finds signs of a cataract while conducting these tests, your most effective treatment option is to entirely replace the lens of the eye through cataract surgery. New advances and techniques in surgical technology have made cataract surgery a safe procedure with a very high success rate. It is performed on an outpatient basis, and more than 95 percent of surgeries ultimately improve vision.