During the past two years, several new lenses have been approved by the FDA for implantation after a cataract has been removed.  These lenses offer exciting options for patients considering cataract surgery, but they may not be the perfect solution for everyone. 

Crystalens Accommodative IOL by eyeonics
In late 2003, the Food and Drug Administration (FDA) approved the Crystalens IOL for use in the United States.  The Crystalens lens is attached to muscles within the eye that allow the lens to flex “to accommodate“ just like the natural lens did earlier in the patient"s life.  In clinical trials, 497 surgeries were performed with the following results:  

• Over 98% of patients who received crystalens implants in both eyes had uncorrected visual acuity of 20/30 or better at distance without glasses (vision of 20/40 or better is needed to pass your driver's license vision test) and could read the small print on a medicine bottle;
• 92% of patients had distance vision of 20/25 or better without glasses;
• 98.4% of patients could read, without glasses, print type the size of stock quotes in the newspaper or phone numbers in the white pages;
• 93.8% of patients indicated that they could perform most daily activities such as shopping or putting on makeup without glasses;
• 85% of patients did not wear eyeglasses to see at night.

ReSTOR multi-focal IOL by Alcon

As noted above, "accommodation" is the term used to describe the flexing of the lens within the eye to change focus between near and far objects, and only a patient's natural lens and the Crystalens are able to accommodate.  The ReSTOR lens, approved by the FDA in March 2005, utilizes an IOL design that incorporates different strengths of vision correction throughout the lens.  Because the ReSTOR lens is not attached to the muscles within the eye, cataract surgery with the ReSTOR lens is virtually identical to traditional cataract surgery in terms of technical difficulty.

This type of lens, featuring different corrections, is called a multi-focal lens.  Alcon has also marketed the ReSTOR as a pseudo-accommodating lens, suggesting that the lens mimics the focusing capability of the natural lens even though the ReSTOR lens does not flex.  The clinical trials monitoring 930 surgeries for the ReSTOR lens provided the following data:

• 84% of patients who received the ReSTOR implants in both eyes had uncorrected visual acuity of 20/25 or better at distance without glasses and could read the stock quotes in a newspaper;
• 80% of patients indicated that they did not use their glasses for any activities after surgery. 

ReZoom multifocal refractive lens by AMO

In late March 2005, the FDA also approved the ReZoom IOL for use in cataract surgery.  The ReZoom IOL distribute light over five optical zones to allow for near, intermediate and distance vision.  The ReZoom lens is also marketed as a pseudo-accommodating lens, but cataract surgery with the ReZoom is virtually identical to traditional cataract surgery.  To date, very little information has been released regarding the ReZoom clinical trials, but we do know that 92% of patients reported either never or only occasionally wearing glasses for distance, intermediate, and/or near vision tasks.

AMO has taken a more methodical approach than Alcon in preparing the ReZoom lens for the marketplace, so the lens may not yet be widely available.