EyeWorld is the official news magazine of the American Society of Cataract & Refractive Surgery.
Issue link: https://digital.eyeworld.org/i/78710
May 2012 Retina February 2011 EW SECONDARY FEATURE 45 Screen potential AMD patients before cataract surgery by Jena Passut EyeWorld Staff Writer A lthough there doesn't seem to be a correlation between cataract surgery and the advancement of age-related macular de- generation (AMD), two physicians who spoke to EyeWorld said clini- cians should continue to carefully examine those patients at risk for the posterior segment disease. "[Cataract surgeons] need to be very careful to risk-assess the pa- tients," said Timothy W. Olsen, M.D., chairman, ophthalmology department, Emory University School of Medicine, Atlanta. "The phenotype of macular de- generation gives the examining physician many clues as to the level of risk for progression," Dr. Olsen continued. "Cataract surgeons' obli- gation is that if they don't feel com- fortable risk-assessing the patient's macula, they need to send it to someone who can." This will give the patient a real- istic expectation about what the short-term and perhaps even 5-year prognosis is for macular degenera- tion, Dr. Olsen said. Several studies have been per- formed since the late 1970s to see whether cataract surgery increases a patient's risk for choroidal neovascu- larization, the primary symptom of neovascular AMD that predicts pro- gressive loss of vision. The results of most of the stud- ies have been inconclusive and hotly contested, especially when it comes to their methodologies. Steven H. Dewey, M.D., Colorado Springs Health Partners, Colo., said that the well-designed Age-Related Eye Disease Study (AREDS) persuasively showed in 2010 that cataract surgery seems to have no effect on the ultimate devel- opment of advanced forms of AMD. "AREDS looked specifically at patients with high-risk characteris- tics for developing macular degener- ation," Dr. Dewey said, adding that the study took the latest tools and techniques into consideration, including UV-blocking IOLs and small-incision phacoemulsification. Earlier studies, without these bonuses, showed mixed results. Blue-blocking IOLs also had no effect on whether a patient at risk for AMD saw the disease progress, Dr. Dewey said. There is one caveat, Dr. Dewey stressed. "Patients at high risk for visual loss are at high risk no matter what," he said. "Cataract surgery isn't going to change their outcome and doesn't improve their out- come." Dr. Olsen pointed out that epi- demiology studies, such as the Beaver Dam Eye Study, conducted in Beaver Dam, Wis., showed a pos- sible connection, but those studies are flawed. "The association of those is a very small number of cases that have AMD when you look at the total numbers," he said. "Cataract surgery techniques have advanced pretty dramatically since those early studies, too." Dr. Dewey suggested always screening at-risk patients for an occult membrane using fluorescein angiography (FA). "There can be nothing obvious on a clinical examination, and then you look back at the FA after cataract surgery and see that these patients had an occult membrane," he said. Cataract surgeons should be able to properly identify problems with the macula, Dr. Olsen added. "The most important thing is for physicians to recognize the pres- ence of AMD," he said. "If they have any concerns about the status of the macula, they need to address it specifically or refer to a retina spe- cialist." Dr. Olsen said that active macu- lar degeneration often may not be recognized or looked for prior to surgery, leading cataract surgeons to proceed. "That puts the cataract surgeon in a difficult position and sometimes the patient can lose confidence in the surgeon," he said. "I think it's important to assess the macula, and if it can't be assessed, then refer to someone who can." Multifocal IOLs for AMD patients? Dr. Dewey said premium IOLs can help patients achieve a better level of vision—toric or accommodative lenses can demonstrate improved contrast sensitivity. "You're still obligated to advise patients somewhere down the road that this lens may not be their lens of choice," he said. "The lenses themselves don't have an effect on progression," Dr. Olsen concurred. "I caution against placing multifocal lenses in eyes with macular degenerative changes, especially more advanced stages, be- cause the patients are usually not very happy with a multifocal lens, in my experience." Dr. Olsen said a lens implant should be fine, as long as the optic is monofocal. "I think some of the accom- modative or pseudoaccommodative designs that don't rely on a multifo- cal plane are certainly reasonable," he said. There is theoretical evidence that yellow-tinted lenses block short- wave light and slow the progression of AMD. "Most of the lenses block UV light, which helps a lot," he said. "In the visible spectrum, the downside to placing a yellow lens is that in low level or dim light or [when] driv- ing at night, it may diminish the more important shortwave light that people use to see in the dark. That's the concern." Some physicians argue that wearing yellow or blue-blocking sun- glasses will allow the patient to take them off, not interfering with the visible light spectrum at night. "That's a debatable topic," Dr. Olsen said. "My preference is for clear monofocal lenses, but I think yellow also is reasonable." Timing, communication are everything Especially important is keeping the lines of communication open with retina specialists, Dr. Dewey advised. "All physicians have to go to their own level of comfort," he said about deciding whether to co-man- age. "Because I have some very good colleagues in town, I let them tackle this specific condition, which they do very well. The biggest thing is [remembering that] sending a pa- tient for a pre-operative evaluation doesn't mean you're less of a physi- cian." Timing is key when it comes to patients with active disease who are receiving anti-VEGF therapy, Dr. Olsen said. "The cataract surgery itself doesn't influence my decision to give an injection," Dr. Olsen said. "The disease process is still ongoing, and they still need therapy for that. It's just a matter of timing." Dr. Olsen said if a patient is on a monthly injection schedule, he prefers that the patient has the cataract surgery in the third week after the last injection. "[The patient is] a week away from getting the next injection, and it gives the eye time to heal a bit," he said. EW References Chew EY, Sperduto RD, Milton RC, et al. Risk of advanced age-related macular degeneration after cataract surgery in the Age-Related Eye Disease Study: AREDS report 25. Ophthalmol- ogy. 2009;116(2):297-303. Tabandeh H, Chaudhry N, Boyer D, et al. Outcomes of cataract surgery in patients with neovascular age-related macular degenera- tion in the era of anti-vascular endothelial growth factor therapy. J Cataract Refract Surg. Vol. 38, April 2012. Editors' note: Drs. Dewey and Olsen have no financial interests related to this article. Contact information Dewey: 719-471-4139, deweys@prodigy.net Olsen: 404-778-4996, tolsen@emory.edu