If you currently have or have had a cataract, you are not alone. Cataracts are very common, affecting about 60 % of the population over the age of 60. Because cataracts gradually result in visual impairment, surgical removal is usually required with about 1.5 million cataract surgeries performed each year in the United States.
A cataract affects the lens of the eye causing it to become clouded. As a cataract develops, vision becomes more impaired due to the light that goes through the lens onto the retina being out of focus from the clouded lens. This causes vision to become distorted and blurry.
Most cataracts are due to aging, although on rare occasions they can be present at birth or develop in early childhood due to genetic factors. The exact cause of cataracts is not completely understood, but most are believed to be caused by protein structure changes in the lens, which slowly occurs over the years. Typically, both eyes are affected, although the rate of progression may be different in each eye. Cataracts can also form due to intraocular inflammation, severe trauma or eye surgery. Factors that can cause cataract formation in earlier years include smoking, certain medications, diabetes or excessive exposure to ultraviolet light.
Because cataracts develop gradually, most individuals will begin to notice changes in vision that cause difficulty with reading and driving. Vision may be blurry or cloudy and colors may become dull. Glare problems may increase and halos can appear around lights. Nearsightedness may occur and frequent eyeglass changes may be needed, which can help until the cataract progresses significantly. Night vision may become poor, double vision may occur or one eye may see multiple images.
Eye-care professionals can detect cataracts using several different diagnostic instruments. They can also diagnose how advanced the cataract has become and how much it has affected vision. Eye examinations will usually include testing for color vision, visual acuity, contrast sensitivity and glare sensitivity. The eye-care professional may perform a dilated eye exam to examine the optic nerve and retina as well as a tonometry test to measure the pressure within the eye. Because cataracts develop slowly, the need to have them surgically removed is usually determined by how impaired vision becomes. Cataract development is different with each individual and some cataracts never progress enough to impair vision or require surgery. Others can develop rapidly causing severe vision difficulties.
When a cataract progresses to the point that it affects vision so that it cannot be corrected with corrective lens, the eye care doctor will recommend cataract surgery. The procedure is usually performed in an outpatient facility. The most common procedure used today is phacoemulsification surgery. This involves making a small incision in the eye’s surface and inserting a tiny ultrasound probe into the eye to dissolve the clouded lens. Fragmented pieces are removed by suction through the probe. An artificial lens is then positioned into the eye where the cataract was removed.
Following cataract surgery, the eye-care professional will require a return visit within a few days. During recovery, several different eye drops will be prescribed to help prevent inflammation and infection. Most individuals experience an improvement in vision within a few days after surgery. Once vision becomes stabilized, patients will be fitted with corrective glasses.
Dunya Carter is a health writer from Sydney. She is a medical student interested in cataract surgery . In her free time she writes for several blogs on topics related to health.