MAR 2014

EyeWorld is the official news magazine of the American Society of Cataract & Refractive Surgery.

Issue link: https://digital.eyeworld.org/i/276058

Contents of this Issue


Page 72 of 210

E W CATARACT 70 March 2014 "This is because the cornea is sufficiently aberrated that the pa- tient may be less likely to tolerate t he reduced contrast inherent to multifocals," Dr. Pepose said. Additionally, Dr. Pepose meas- ures the patient's angle kappa and avoids ReSTOR lenses (Alcon, Fort Worth, Texas) if it is over 0.4 mm and avoids a Tecnis lens (Abbott Medical Optics, AMO, Santa Ana, Calif.) if it is over 0.5 mm—due to research that indicated multifocal patients' complaints of glare and halos positively correlated with p reop 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. A dditional screening by James Davison, MD, Wolfe Eye Clinic, Waterloo, Iowa, avoids using multi- focal lenses in patients with substan- tial 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. A mong the emerging realiza- tions 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 profes- sions. He has implanted multifocal IOLs with good clinical results in engineers, lawyers, and physicians. Despite the concerns of some sur- geons 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 have the capacity to understand and appreciate their performance expec- tations. Surgical pearls offered Among the surgical steps likely to improve clinical outcomes for multi- focal recipients, Dr. Davison said, is the use of femtosecond laser cataract surgery. Specifically, femtosecond systems can provide more pre- dictable and precise transverse arcuate keratotomy (TAK) to reduce astigmatism in more potential multifocal recipients. The ability of femtosecond lasers to treat up to 1.5 D of keratometric astigmatism essentially doubles the potential re- cipients of multifocal lenses, he said. Additionally, the femtosecond laser-provided capsulotomies have enabled improved performance for all types of lenses. However, there are no apparent benefits for helping t he lens find the best position within the capsular bag for centration. "You can't tell exactly where the lens is going to sit," Dr. Davison said. "All you can do is dial it in and put it where you think is the best orientation at the time of surgery." "The performance of multifocal I OLs is very susceptible to the effects of residual refractive error in either defocus or astigmatism," said Dr. Pepose. "It is very important to achieve a postoperative emmetropic outcome, which at times requires a laser vision enhancement." He avoids Tecnis multifocal IOLs in patients with larger pupils due to p revious research indicating worse intermediate vision among that group. 2 The Crystalens AO (Bausch + Lomb, Rochester, N.Y.) has superior intermediate vision, although the near point is less, he said. Diffractive IOLs with add powers less than 3.0 are now undergoing clinical trials and may allow surgeons to further customize the patient's intermediate vision. In the meantime, Dr. Pepose urged meticulous cortical cleanup and removal of all of the viscoelastic beneath the IOL. Additionally, he tries to decenter multifocal IOLs slightly nasally in the capsular bag in an effort to be more closely aligned to the visual axis. Other surgical interventions to improve the postop outcomes and reduce the occurrence of blurred vision or dysphotopsias include aggressively treating dry eye and any posterior capsular opacification. EW References 1. Prakash G, Prakash DR, Agarwal A, et al. Predictive factor and kappa angle analysis for visual satisfaction with multifocal IOL implantation. Eye. 2011;25:1187-1193. 2. Packer M, Chu RY, Waltz KL, et al. Evaluation of the aspheric Tecnis multifocal intraocular lens: One-year results from the first cohort of the Food and Drug Administration clinical trial. Am J Ophthalmol. 2010:149:577-584. Editors' note: Dr. Pepose has financial interests with Abbott Medical Optics, Bausch + Lomb, and Clarity Medical Systems (Pleasanton, Calif.). Dr. Davison had no financial interests related to this article. Contact information Pepose: jpepose@peposevision.com Davison: jdavison@wolfeclinic.com Preparation continued from page 69 64-75 Cataract_EW March 2014-DL2_Layout 1 3/6/14 3:10 PM Page 70

Articles in this issue

Links on this page

Archives of this issue

view archives of Eyeworld - MAR 2014