intraocular lens

eye surgery

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Last updated

July 21, 2026

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An intraocular lens (IOL) is an artificial lens used in eye surgery, most commonly to replace a natural lens that has become clouded by a cataract. The natural lens of the eye, a transparent, biconvex structure behind the iris, normally focuses light onto the retina. However, with age or certain conditions, this lens can become opaque, leading to vision problems.

Cataract surgery involves removing the clouded natural lens and implanting an IOL. These artificial lenses can be monofocal, designed for a specific distance, or multifocal, allowing for clearer vision at various distances and potentially reducing the need for glasses or contact lenses. This procedure significantly improves vision for individuals affected by cataracts.12

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cataract
Such implants, known as intraocular lenses, may be monofocal (set for near, far, or intermediate vision) or multifocal, which can be moved by the eye muscles to accommodate focused vision at different distances; the latter type of implant reduces the need for contact lenses or eyeglasses.
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Such implants, known as intraocular lenses, may be monofocal (set for near, far, or intermediate vision) or multifocal, which can be moved by the eye muscles to accommodate focused vision at different distances; the latter type of implant reduces the need for contact lenses or eyeglasses.
Read More