• Written By: Adam J. Gess, MD
    Cataract/Anterior Segment

    This prospective study found that the Crystalens AO accommodating IOL provided better intermediate vision and less photic phenomena but worse near visual acuity than the AcrySof IQ ReSTOR +3.0 multifocal IOL and the Tecnis multifocal IOL.

    The authors compared contrast sensitivity, visual acuity and halos in 78 subjects bilaterally implanted with the Crystalens AO, the AcrySof IQ ReSTOR +3.0 or the Tecnis Multifocal. Subjects were evaluated through four visits up to six months after surgery.

    Subjects with the Crystalens AO had statistically better uncorrected intermediate visual acuity and distance corrected visual acuity and fewer photic phenomena than those with the Tecnis Multifocal lens, and less optical scatter than either multifocal IOL. Those implanted with either multifocal IOL had better distance corrected near visual acuity and uncorrected near visual acuity than those with the Crystalens AO.

    The authors note that the method used for determining defocus curves in this study was not ideal for accommodating IOLs. Because the design of multifocal IOLs is based purely on optical principles, using lenses with targets set at fixed distances works well because the induced defocus is strictly optical. However, this method is not as suitable for accommodating IOLs because they require accommodative effort to work, which is optimized with binocular viewing along with convergence. In future studies, it would be better to measure defocus curves using real targets at real distances that correspond to the desired defocus, a technique that would work equally well with accommodating and multifocal IOLs.

    They conclude that this study confirms the established safety and effectiveness of all three IOLs. Each has features that may benefit any patient depending on the lighting, image contrast and fixation distance. Lens selection should be guided by their demonstrated attributes in conjunction with the patient's visual demands, expectations and ocular characteristics and the surrounding environmental conditions.