Since our practice began offering presbyopia-correcting IOLs, we have implanted 450 of them. One in five of our cataract and refractive lens exchange patients chooses one of these new lenses. The AcrySof ReSTOR lens (Alcon Laboratories) accounts for 80% of our presbyopia-correcting implants, while the ReZoom (Advanced Medical Optics) and the crystalens (eyeonics) together represent 20%.
Determining visual needs
Offering presbyopia-correcting IOLs requires that physicians pay very close attention to patients' visual needs, i.e., what they want their surgery to allow them to do. First, patients fill out a questionnaire on which they list the activities they need or want to do most. The majority of our patients report that being able to see at near and distance is most important to them. They also indicate that if they can have good vision at those two distances, they could tolerate occasionally having to wear glasses for other activities. In this scenario, the ReSTOR lens is their best option.
We take a careful approach to mixing and matching lenses for several reasons. Mainly, we believe the apodized diffractive optic design of the ReSTOR lens gives patients the best chance of good functional vision without correction at near, intermediate, and distance-especially when they have bilateral implants. Given what we know about binocular summation (that bilateral vision is better than vision with one eye), I am not convinced that using two very different types of lenses in one patient is the best way to maximize the visual system.
Our results confirm this. Patients who have received the ReSTOR lenses have excellent near and distance vision, and their intermediate vision is better than I had anticipated. By tracking satisfaction among patients who received bilateral ReSTOR lenses and remain in our care after surgery, we have learned that 90% never wear glasses; 100% have better than 20/40 uncorrected distance vision; and 90% see J3 or better at near. In addition, patients who use computers do better with ReSTOR lenses than has been reported. Furthermore, patients are generally satisfied with their first ReSTOR implant, but are happiest once they receive their second one. We do find these patients may need a little more light for their intermediate distance viewing, but generally they function very well under normal lighting conditions.
Prior to initiating the trial waiting period before implanting a different lens in the second eye, we had used the mix-and-match strategy in six patients. One of those patients is unhappy with the results. Because she uses the computer frequently and also reads a lot, we implanted a ReSTOR lens in her non-dominant eye and a ReZoom lens in her dominant eye. She has requested that we remove the ReZoom lens, and we have advised her to take more time to try to adjust before we proceed.