Intraocular lenses (IOL) are lens implanted in the eye used to treat cataracts or myopia. The most common type of IOL is the pseudophakic IOL. The pseudophakic IOL replaces the original crystalline lens and provides the light focusing function originally undertaken by the crystalline lens. The second type of IOL, more commonly known as a phakic intraocular lens (PIOL), is a lens which is placed over the existing natural lens and is used in refractive surgery to change the eye’s optical power as a treatment for myopia or nearsightedness.