Eyeworld

EW FEATURE 48 Presbyopia treatment • August 2016 AT A GLANCE • Stage 1 of dysfunctional lens syn- drome (DLS) includes deterioration of patients' ability to read close up or when myopic patients need to take off their glasses to read. • Stage 2 of DLS typically occurs among patients in their 50s and 60s and is demonstrated by deterioration of their night vision. • Stage 3 occurs with the development of a visually significant cataract. by Rich Daly EyeWorld Contributing Writer to those tracks," Dr. Waring said. "If you talk about the first 2 tracks—the cornea- and the lens-based tracks— our practice does an all-digital lens- based exam using digital imaging of the internal crystalline lens, with functional analysis of the lens, such as optical scatter index with double pass wavefront (HD Analyzer). In ad- dition to densitometry, we perform qualitative analysis with Scheimp- flug imaging, which allows us to grade the DLS and decide whether the patient will be best served by a corneal-based procedure or a lens- based procedure." Criteria for exclusion Risk factors for the development of ectasia are usually the first compli- cations Dr. Waring looks for when considering corneal options, which also applies to corneal inlays. Another contraindication for a corneal-based treatment among stage 1 DLS patients is any sort of lens opacity that is not affecting their daily activities. Such patients would be better served by a refrac- tive lens-based procedure. Monovision is not a reliable op- tion for patients who require prisms to correct double vision, as well as those with clinically significant ocular pathology in the dominant eye that disallows them from having uncorrected visual acuity of 20/20 or better. In stage 3 patients still have presbyopia but the degraded lens optics leave lens replacement as the only option. Dr. Durrie even explains DLS to younger patients who want to know whether LASIK is permanent. Un- derstanding the stages of DLS helps clarify that LASIK does not wear off but that their vision will be affected by their lens changes. "We want them to know that there are 2 lenses in the eye," Dr. Durrie said. "When they're young, we fix the cornea and when they're older, we fix the lens. It's worked out well and we've been doing this for quite a few years." The age component is another key to use of DLS to drive treatment decisions, said George Waring IV, MD, associate professor of oph- thalmology, director of refractive surgery, Storm Eye Institute, Medical University of South Carolina, and medical director, Magill Vision Cen- ter, Charleston, South Carolina. Patients younger than 50 years old are placed in the corneal refrac- tive track, while those older than 50 who are not complaining of cataract symptoms are put in a refractive lens track. Patients older than 65 years and complaining of symptoms consistent with cataract are put on a cataract track. "From that point on we are doing different evaluations specific Patients in their 40s are usually in stage 1 of DLS, which they expe- rience as the deterioration of their ability to read close up. They need to push everything farther away, they start buying reading glasses, or myopic patients start taking off their glasses to read. "When we describe it by how it's affecting them, the patients understand it and they know that is stage 1 of DLS," Dr. Durrie said. Stage 2 of DLS typically occurs in patients in their 50s and 60s and is demonstrated by a deterioration of their night vision and the need for more light to read. At this point, ophthalmologists begin to see some haziness in the junction between the nucleus and the cortex of the lens, and the lens starts turning yellow. "We may call this nuclear sclerosis on the scientific side but to patients we talk about stage 2 of dysfunctional lens syndrome," Dr. Durrie said. Stage 3 occurs with the devel- opment of a visually significant cataract. Understanding options After explaining the DLS stages to educate patients on ways their refractive vision is going to change over their lifetime, surgeons use it to inform their decision tree. In stage 1, the treatments are LASIK or PRK monovision, or blended vision, which is a lower level monovision; corneal inlays; and refractive lens exchange for patients who are hy- peropic above a couple of diopters. Inlays fall out as an option in stage 2 because of the loss of optical quality, which diagnostics can demonstrate to the ophthalmologist and the patient. Diagnostic tools, like the HD Analyzer (Visiometrics, Terrassa, Spain), can identify major ocular scatter—how much light is lost when the lens goes through stage 2 changes. "There are still some gray areas; we're still able to do LASIK monovi- sion in the 50s and 60s, but we talk to patients about the fact that even- tually they are going to go to stage 3 or late stage 2 and need to have a lens procedure," Dr. Durrie said. "So a lot of our patients will choose to have lens procedures in their 50s or 60s because it avoids cataract and gets to the root of the problem for presbyopia." Surgeons have found that discussion of dysfunctional lens syndrome is easy to understand and provides a helpful guide for the growing number of treatment options W hat do clinical terms like presbyopia, nucle- ar sclerosis, and lens accommodation mean to patients? Unfor- tunately, even carefully explained clinical terms can leave patients confused about the status of their re- fractive vision and what that means for their treatment options. Some surgeons are turning to a newer approach that explains patients' refractive vision as falling into 1 of 3 progressive stages of dysfunctional lens syndrome (DLS). That approach can help patients understand why their vision is changing with age and how vari- ous treatment options can provide refractive improvements. How it works The first step to determine what stage of DLS a patient's vision falls into is completion of a comprehen- sive exam, said Daniel Durrie, MD, professor of ophthalmology, Univer- sity of Kansas Medical Center, and founder of Durrie Vision, Overland Park, Kansas. "If they are older than 43, then they already know something is changing and we start talking to them about what is going on in the lens," Dr. Durrie said. Tips for effective patient presbyopia discussions In the 2015 ASCRS Clinical Survey, ASCRS members were asked, "What do you think will be your primary surgical presbyopia correction solution(s) in the next 3 years?" The results show that 52% of respondents plan to use a multifocal IOL as their primary surgical solution for presbyopia patients ages 45–54.

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