Eyeworld

3 Supported by Abbott Medical Optics Inc., Alcon Laboratories Inc., and AcuFocus 3 Customization based on presbyopia stage and patient's visual goals is key in presbyopia correction T o provide the range of vision that today's pres- byopic patients expect, we need to match our surgical strategies and technology to their stage of pres- byopia and their visual goals and requirements. In addition to staging the progression of presbyopia and the status of the lens, in my practice we customize treatment to the patient's current refraction, with different choices for emmetropes, hyperopes, and myopes. For example, I would typical- ly treat a myopic early presbyope with laser vision correction, using a bit of defocus in the nondom- inant eye. Monovision is best suit- ed for patients who wear contact lenses for monovision. In patients without monovision experience, we may perform a contact lens trial before surgery. Presbyopic emmetropes are among the most difficult patients to satisfy. Anything we do to cor- rect presbyopia affects their excel- lent uncorrected distance vision. Some plano patients do well with refractive lens exchange with a multifocal IOL or accommodating IOL, which usually is implanted in the nondominant eye. Howev- with minimal impact on distance vision (Table 1). More research needs to be done to understand the ideal refractive targets with these new IOLs. We need to bear in mind that patients' expectations and visual requirements often depend on their occupations, pastimes, and personalities. During preoper- ative counseling, I listen carefully to patients' visual goals. Based on the exam and their requirements, I offer a definitive recommenda- tion rather than several choices, which may confuse patients. When troubleshooting residual error, our first step is to determine the cause. Some pa- tients may require ocular surface treatment, but others may need laser vision correction, astigmatic keratotomy, or limbal relaxing incisions. In more extreme cases, we may need to perform a refrac- tive lens exchange or implant a piggyback IOL. To determine whether we have helped our patients achieve their goals, we ask them to com- plete short surveys. By customizing treatments to meet presbyopic patients' visual goals and needs and assessing their satisfaction, we can achieve better outcomes and build our practices. Dr. Dell is medical director of Dell Laser Consultants in Austin, Texas. He can be contacted at steven@ dellmd.com. transition to an astigmatism-cor- recting IOL. The only IOL avail- able to treat both presbyopia and astigmatism is the Trulign IOL (Bausch + Lomb). I think extended range of vision sphere and toric IOLs, when they become available, will significantly change our practice pattern. During a multicenter study with 3-month follow-up, patients with bilaterally implanted ex- tended range of vision (EROV) IOLs (Tecnis Symfony, Abbott Medical Optics) had 20/20 or better mean uncorrected distance vision, 20/20 or better mean distance-corrected intermediate vision, and a 2-line improvement in distance-corrected near over control. There was not a signifi- cant difference in glare or halos compared with monofocal IOLs. A toric version of this lens is also available outside the U.S. Visual satisfaction The degree of tolerable postoper- ative refractive error depends on the technology we choose. We need to achieve spot-on refractive outcomes with multifocal IOLs. Even 0.5 D of astigmatism, hy- peropia, or myopia can affect the intended function of these lenses. EROV lenses may tolerate defocus better. Investigators have recently begun to test the effects of micro-monovision in patients implanted with EROV lenses and have found that a –0.75 D target can further improve near er, patients must be motivated to achieve spectacle independence at near. In hyperopes with early presbyopia, I rely on refractive lens exchange with an accommo- dating or multifocal IOL. If they need spectacles for distance, we perform bilateral refractive lens exchange. The lower add power mul- tifocal IOLs (e.g., +3.25, +2.75 D, or +2.50 D) have been a game changer, providing higher patient satisfaction and better visual qual- ity while allowing patients to read close up. At the later stages of presby- opia or if patients require cataract extraction, lens surgery would be preferred, and we would select the option that best meets the patient's visual goals. Possibilities include monovision, multifocal IOLs, accommodating IOLs, or a mix-and-match approach. Astigmatic considerations and new IOLs For cataract surgery or refrac- tive lens exchange in astigmatic patients, the choice of a toric or multifocal IOL depends on the degree of astigmatism and the patient's desire for presbyopia cor- rection. We can treat very small degrees of corneal astigmatism with arcuate corneal incisions, but when astigmatism is between 1.0 and 1.5 D, most surgeons by Steven Dell, MD Presbyopia stages and the role of refractive error Mean visual acuity (logMAR) Far Intermediate Near Uncorrected –0.048 0.028 0.207 Distance-corrected –0.112 –0.031 0.195 0.50 D monovision –0.049 –0.015 0.130 0.75 D monovision 0.011 –0.049 0.071 1.00 D monovision 0.049 –0.078 0.022 Table 1: Monovision of –0.75 D resulted in 0.12 logMAR reduction from distance-corrected VA at far, no significant difference at intermediate, and 0.12 logMAR improvement at near, Encore Study Steven Dell, MD

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