Intraocular Lenses (IOL)

It is possible to implant a lens in the eye without removing the natural lens. A flexible lens is inserted through extremely small incisions in front of the natural lens to correct nearsightedness or farsightedness. Once in the eye, the lens expands to its full size, allowing the eye to remain relatively untraumatized, thus reducing astigmatism and recovery time.

A phakic intraocular lens (PIOL) is a lens implanted inside the eye for the correction of either extreme nearsightedness or extreme farsightedness. In effect, the lens becomes an internal contact lens rather than a contact lens on the surface of the eye. It is usually recommended for patients whose visual correction is outside the range that can safely be treated with LASIK.

Because of the slightly increased risk of more serious complications, the PIOL is reserved for high amounts of nearsightedness or farsightedness--above the current limits of LASIK. In places where this technology is available, surgeons are implanting the PIOL in patients with myopia greater that 12.00 to 15.00 diopters and hyperopia greater than 4.00 to 6.00 diopters.

Despite the excellent outcomes in most cases, complications associated with the implants are currently the biggest concern. Specifically, in the early studies a small percentage of patients developed cataracts shortly after implantation of the lens. There is also a small risk of endophthalmitis (infection within the eye) because the surgical incision actually enters the eye. This rare complication could lead to complete loss of vision. Endothelial cell loss with some lens designs is also a concern and is being studied rigorously.

There are two currently Food and Drug Administration (FDA) approved Phakic Intraocular Lenses that Ophthalmologists in the United States may use for suitable patients. These are the Verisyse Phakic Intraocular Lens and the Visian Implantable Collamer Lens.