Cataract is the leading cause of preventable blindness world wide. The human eye has two structures that act as lenses to focus light on to the retina. The first one is called cornea and is part of the outer structure of the eye and the second, called crystalline lens (or just lens), is located inside the eye. As we age, the crystalline lens changes its biochemical properties and physical structure leading to its opacification. This opacification of the natural crystalline lens is called cataract. Cataracts disturb image formation and distorts vision. Its treatment is fundamentally surgical and there are no effective clinical alternatives to solve this condition. This is a progressive disease and, therefore, as time goes, its effects becomes more and more important. However, at initial stages, this condition might not cause any visual disturbances. This way, surgery is recommended as soon as the person start to notice his/her visual performance to decrease.
Cataract surgery is one of the most successful surgery in the whole medicine. This can be confirmed by the high number of surgeries performed globally. Annually, there are approximately 5 million cataract surgeries being performed in the world. The technological apparatus required for this surgery grows every year to improve even more its safety and precision. Nevertheless, one cannot think that it is an easy or risk free surgery. Precise preoperative measurements of the eye, an adequate lens choice and a very skilled surgeon are necessary in order to achieve a successful outcome.
Today, the modern surgery consists in an approximately 2mm incision followed by the emulsification and aspiration of the crystalline lens and the implantation of an artificial lens. This latter lens is inserted folded through the original small incision and fixates in a structure called capsular bag. Local anesthesia is used and the procedure is completely pain free in the vast majority of patients.