Author(s): Joseph L Goldstein 
Cataracts are the major cause of reversible blindness throughout the world, affecting about 20 million people. Until 1970, cataracts were the leading cause of blindness in the United States. Today, in the United States and other industrialized countries, cataracts are no longer a significant cause of blindness. This achievement can be traced in large part to the development of a simple, small-incision cataract operation pioneered by Charles D. Kelman, this year's recipient of the Lasker Clinical Medical Research Award (Fig. 1). The outpatient procedure pioneered by Kelman, called phacoemulsification, has now become the most commonly performed elective surgical operation in the western world. In the United States alone, nearly 3 million Kelman-type cataract operations were performed last year .
Cataracts occur when the clear crystalline lens of the eye becomes clouded, resulting in partial or complete loss of vision. Although cataracts result from many conditions (such as trauma, genetic diseases and diabetes), the most frequent cause is the natural aging process. More than one-half of the population older than 65 years develops impaired vision caused by cataracts. There are no diets, drugs or eyedrops that will make a cataract disappear; the only treatment is surgical removal. Historically, cataract surgery is one of the oldest operations, second only to circumcision.
Before Kelman--inpatient cataract surgery
In 1970, before the era of Charles Kelman, the surgical removal of cataracts was a major ordeal, requiring a hospital stay of 10 days (if no complications occurred) and a convalescence of several months . Typically, the patient underwent general anesthesia, after which a large, semicircular (180[degrees]) incision was made in the cornea to allow the entire lens to be grasped with a forceps and pulled from the eye in one piece. Eight or more sutures closed the incision, and the patient was kept on absolute bed rest for 3-5 days with both eyes occluded with patches. To restrict movement of the head, sandbags were placed along both sides of the head, and both wrists were bound with restraints to the bed. This enforced immobilization often led to mental disorientation, prostatic obstruction, bedsores and pulmonary embolism. As many as 20% of patients developed vitreous hemorrhage, macular edema, eye infections and retinal detachment. After discharge from the hospital, the eyes and lids remained red, swollen and irritated for as long as 6 weeks. The surgically treated eye had to be patched for several months, and the aphakic patient had to wait for as long as 6 months to be fitted with thick spectacle glasses.
In the early 1950s, an important advance in cataract surgery occurred with the invention of the artificial intraocular lens by Harold Ridley, an ophthalmologist at St. Thomas and Moorefield Eye Hospital in London . Ridley's invention was conceptually quite radical and went against the long-standing dogma that a foreign...