EyeWorld Asia-Pacific June 2014 Issue

43 EWAP CAtArACt/IOL Pseudophakic dysphotopsia June 2014 by rich Daly EyeWorld Contributing Writer Preparation, patient fit keys to multifocal success The unique advantages and limitations of multifocal IOLs require surgeons to focus on patient selection and screening to ensure their optimum use A mid continuing concerns that multifocal lenses are fraught with unwanted side effects, surgeons stress the importance of using careful patient screening and selection criteria to maximize the likelihood of patient satisfaction. Multifocal IOLs—a popular lens choice for motivated patients who would like to achieve spectacle independence—continue to face challenges in their postop outcomes, noted a literature review in the January issue of Current Opinion in Ophthalmology . The review concluded that existing research has not provided significant improvements in resolving the current problems of blurred vision and dysphotopsias. Given those challenges, surgeons’ efforts to increase the likelihood of positive clinical outcomes and minimize postop complications are increasingly critical. Preop screening detailed Among the evolving multifocal lens patient selection procedures used by Jay S. Pepose, MD, director, Pepose Vision Institute, and professor of clinical ophthalmology, Washington University School of Medicine, St. Louis, Mo., U.S., is a Humphrey topographer (Carl Zeiss Meditec, Jena, Germany) to analyze the corneal wavefront. If either the horizontal or vertical coma term at a 6 mm optical zone is over 0.3 microns, he avoids implanting a multifocal IOL. “This is because the cornea is sufficiently aberrated that the patient may be less likely to tolerate the reduced contrast inherent to multifocals,” Dr. Pepose said. Additionally, Dr. Pepose measures the patient’s angle kappa and avoids ReSTOR lenses (Alcon, Fort Worth, Texas, U.S.) if it is over 0.4 mm and avoids a Tecnis lens (Abbott Medical Optics, AMO, Santa Ana, Calif., U.S.) if it is over 0.5 mm—due to research that indicated multifocal patients’ complaints of glare and halos positively correlated with preop values of angle kappa. 1 Other preop screening steps include the use of macular OCT to rule out epiretinal membranes or other pathology that can reduce contrast and affect the performance of multifocal IOLs. Finally, Dr. Pepose screens using tear osmolarity and other dry eye tests to allow aggressive pretreatment of dry eye and continuing treatment in multifocal IOL recipients. Additional screening by James Davison, MD , Wolfe Eye Clinic, Waterloo, Iowa, U.S., avoids using multifocal lenses in patients with substantial amounts of meibomian gland disease, corneal ABM dystrophy, corneal endothelial dystrophy, glaucoma, or minimal to moderate macular degeneration. “Patients with minimal macular degeneration around 75 or 80 years old might be OK, but if they’re 55 years old and already have some moderate changes, a multifocal lens might not be best because they probably won’t do as well as they should 15 years down the line,” Dr. Davison said. Among the emerging realizations about multifocal technology is that older patients can derive good clinical results from its use, Dr. Davison said. Surgeons have found recipients in their 80s have had good visual results from multifocal lenses. The limitations of the lenses require a patient personality that does not demand perfection. “If people seem unreasonable, hard to deal with, their expectations are way too high, or they are worried about it working properly then they are probably not good risk takers for the technology,” Dr. Davison said. However, Dr. Davison does not limit the lenses based on professions. He has implanted multifocal IOLs with good clinical results in engineers, lawyers, and physicians. Despite the concerns of some surgeons that people in technical professions are too demanding to accept the limitations and possibility of side effect with multifocals, Dr. Davison has found these patients The apodized refractive-diffractive SN6AD1 (Alcon) features circular diffractive discontinuities on the anterior central optic. Source: James A. Davison, MD, FACS continued on page 44