Non-Age-Related Cataracts Are Treatable With Surgery

More than two-thirds of people over the age of 60 will have a vision problem due to cataracts, so we usually think of the disease as one related to aging. However, cataracts -- the clouding of the lens inside the eye -- can strike at any age. The clouding of the lens scatters the light rays and prevents a clear image from being formed.

The exact mechanism that causes cataracts is not well known. It is thought that the composition of the lens changes with time and contributes to the development of cataracts. Non-age-related cataracts might be caused by trauma to the eye, use of certain medications such as corticosteroids, exposure to radiation or ultraviolet light, or metabolic disturbances, such as diabetes. In addition, some people are born with cataracts.

Chronic use of steroids for such conditions as asthma, rheumatoid arthritis or following organ transplantation can cause cataracts. Prolonged use of topical steroid creams on the eyelids may lead to cataract formation. Both the strength and duration of the steroid medication influence the formation of the cataract. Individuals who receive radiation therapy for cancer treatment or have excessive exposure to ultraviolet light from the sun are also at risk. In addition, diabetics account for a large portion of patients with non-age-related cataracts. The cause of diabetic cataracts is thought to be due to metabolic changes in the lens which occur secondary to hyperglycemia.

There are different types and degrees of cataracts and one lens may have a combination of the different types. Cataracts involving the back part of the lens are termed "posterior subcapsular" and most often occur from chronic steroid use or exposure to radiation. Cortical cataracts occur in the outer layer of the lens, and nuclear cataracts, which occur in the center of the lens, are most common in cases of age-related cataracts.

Surgery and Prevention

Cataracts usually cause a gradual blurring of vision, over months to years. However, some cataracts can progress very quickly; trauma to the eye may cause a cataract to form within hours. Mild cataract formation may cause no symptoms initially. With time, blurry vision and glare are the two most common symptoms that occur.

A common "slit lamp" exam, preferably with dilation, is used to peer into the eye to detect cataracts. The only treatment is surgery, which is recommended when daily activities, such as reading or driving, become difficult. A small percentage of individuals may have their cataracts removed early to allow monitoring of diseases of the retina.

Surgery involves an incision on the eye. The lens is removed and replaced with a lens implant that can be corrected for nearsightedness or farsightedness. However, glasses or contact lenses may still be required as before the surgery. Surgery takes just 15 to 30 minutes and uses topical or local anesthetic. Typically there is no pain during or following surgery. A patch may be worn over the eye for several hours to a day. It will take several weeks for the eye to completely heal and for vision to stabilize. Some patients, however, experience good vision the day of surgery.

Prevention of cataracts includes the use of UV-coated sunglasses while outdoors. Individuals using high dosages of corticosteroids, or other medications which contribute to cataract formation, should consult with their physician for a possible lower dose or less frequent dosing of the medication.

MCW Health News presents up-to-date information on patient care and medical research by the physicians of the Medical College of Wisconsin.