What is an intraocular lens (IOL)?
An intraocular lens (IOL) is an implanted lens in the eye, usually replacing the existing crystalline lens because it has been clouded over by a cataract, or as a form of refractive surgery to change the eye’s optical power. It usually consists of a small plastic lens with plastic side struts, called haptics, to hold the lens in place within the capsular bag inside the eye. IOLs were traditionally made of an inflexible material (PMMA) though this largely been superseded by the use of flexible materials. Most IOLs fitted today are fixed monofocal lenses matched to distance vision. However, other types are available, such as multifocal IOLs which provide the patient with multiple-focused vision at far and reading distance, and adaptive IOLs which provide the patient with limited visual accommodation. Insertion of an intraocular lens for the treatment of cataracts is the most commonly performed eye surgical procedure. The procedure can be done under local anesthesia with the patient awake
Intraocular lenses are small prescription plastic lenses which are placed in the normal position of the natural human lens after removal of a cataract. This helps restore the normal focusing properties of the eye after cataract surgery. They have been successfully used in millions of people in the last 20 years. Prior to IOLs, patients having cataract surgery would be forced to wear thick glasses or contact lenses to restore their vision. Unlike contact lenses, IOLs are permanently placed in the eye. Patients can not feel or see their IOL after surgery and they normally never need to be removed or changed. Prior to cataract surgery, ultrasonic measurements are made of the size and curvature of the eye. These measurements are used to select the proper prescription of the IOL. Because an IOL is a prescription lens, most patients attain excellent vision and often reduced need for glasses after surgery, even if they required strong glasses for nearsightedness or farsightedness before their
