By Aparna Mani, MD, PhD
MGH Medical Walk-In Unit
Much like with a camera, the lens of the human eye helps to bring the image you’re looking at into focus. The lens measures in length about half the diameter of a dime and is made of a gel-like protein called collagen. Through the work of thin muscle fibers, the lens changes its shape to bring objects into focus. With age, pigment can collect and cloud the crystal clear lens resulting in vision loss. This clouding of the lens, called a cataract, is the leading cause of blindness worldwide. Since the normal aging process is one of the main causes for cataracts, we are all at risk for developing cataracts. However, people with diabetes, those who use corticosteroids for an extended period of time (for instance as treatment for asthma or arthritis), who smoke, or have a family history of cataracts are at increased risk.
Though painless, the presence of a cataract may cause symptoms such as increased glare from lights, difficulty with night driving, difficulty reading, and reduced ability to appreciate colors. The severity of these symptoms can increase over time and begin to impact one’s lifestyle. Though your health care provider may be able to pick up the presence of a cataract during a routine visit using an ophthalmoscope, you will need a comprehensive exam and detailed vision testing by an ophthalmologist to fully assess a cataract. Recommendations on management and treatment is based on this assessment.
Currently, the only treatment for cataracts is surgery, normally done in an outpatient setting. Depending on the degree of the cataract and its impact on vision, the ophthalmologist may recommend observation and follow up vision testing for a period of time, or proceeding with surgery to treat the cataract. With surgery, the clouded lens is removed and replaced with an artificial one made of plastic or silicone to restore vision. Results are usually apparent right away within hours to a few days of post-operative healing.
Though there is no proven therapy to reduce or slow the progression of cataracts, some studies have suggested that eating a healthy diet rich in fruits, vegetables and vitamins such as lutein is associated with a lower risk of developing a cataract. In addition, since smoking is a risk factor for cataract development, quitting tobacco use may help prevent cataract formation.