An intraocular lens (IOL) replaces the existing crystalline lens of the eye. It’s most commonly used in cataract surgery, but in recent years is also used in a refractive lens exchange procedure.
This flexible lens is made of plastic and has side struts to hold it in place. Using a minuscule incision, it is inserted by an ophthalmic surgeon via tube, then unfurls within the capsule of the lens.
These intraocular lenses have improved significantly over the past few years. There is now a wide range of lenses for an ophthalmologist to choose from, allowing for correction of pre-existing refractive errors such as long-sightedness, short-sightedness, and astigmatism. Multifocal and accommodating lenses allow for both near vision and distance vision at the same time. Toric IOLs will correct astigmatism.
The very latest artificial lenses, trifocal lenses, will give clear vision without glasses at near (reading), mid and distance.
If an IOL is used solely to correct a refractive error, there are several types of lenses that a surgeon would consider using. Phakic IOLs are used when the natural crystalline lens of the eye isn’t removed while aphakic IOLs completely replace the natural lens of the eye.
IOLs have allowed people who aren’t suited for laser vision correction (particularly those over the age of 50) to reduce their dependency on (or even completely eliminated the need for) glasses. Whether performed on a cataract or refractive lens exchange patient, once the human lens has been removed a cataract can no longer develop.