EyeWorld India March 2012 Issue

47 March 2012 EW RETINA the severity of the DME before cataract surgery. “Maybe the density of the cataract does not allow a good enough treatment by laser before the procedure because there are those lens opacities in the way,” he said. If a patient does have a dense cataract and you suspect he may have DME, Dr. Mahmoud suggested doing a Potential Acuity Meter test, even though it’s not always the most reliable. You can also try an optical coherence tomography (OCT), but if it’s really bad the OCT might not measure it, Dr. Telander said. “The studies are conflicting, but if there is an effect on DME on contemporary, uncomplicated phaco, the effect is probably pretty small,” said Dr. Loewenstein. “The effect is more likely to be on OCT measurement of central macular thickness rather than visual acuity. Also it may be transient. There are some studies that show that the thickening is more likely to occur within 6 weeks after surgery, and then there’s no difference between patients with DME and without DME at 6 months.” Another study Dr. Mahmoud pointed to was in a 2009 Ophthalmology publication (2009 Jun;116(6):1151-7), which specifically looked at patients with DME at baseline, randomized into two groups. One group had phaco in conjunction with an Avastin (bevacizumab, Genentech, South San Francisco, Calif., USA) injection, and the second group had only phaco. “They found that at 3 months both groups improved significantly,” he said. “However, the group that had the Avastin injection had significantly better visual acuity at 3 months and a much decreased retinal thickness by OCT. How do we explain this? We can explain this by saying that having one of those injections at the time of cataract surgery or before cataract surgery can improve the short- and long-terms outcomes of patients with DME.” In addition, after cataract surgery, prognosis often depends on how inflammatory the surgery was, said Dr. Telander. “The more inflammatory it is, the more increased macular edema you have,” he said. “So if patients already had some DME, it will be worse, and if they didn’t have any they can still have it. If they already have DME you should anticipate that it’s going to get worse with any inflammation.” The trick with multifocal IOLs Dr. Mahmoud can’t say for certain that surgeons should not put a multifocal IOL in a diabetic patient after cataract surgery, but he does advise retina surgeons to be aware of the issues that could arise. “You need good visualization with a contact lens to be able to deliver a good focal laser for DME,” he explained. “This view will not be the same for the multifocal lenses. One of the options we have for focal lasers nowadays is the PASCAL laser. I think we have to be very careful and do specific studies that look at safety using those types of lasers with diabetic patients with macular edema if a patient has a multifocal lens in the eye because the refractions of the multifocal lenses may be different.” Dr. Mahmoud advised surgeons to use “regular, single-spot lasers” until adequate safety data on other lasers become available. “At each spot you’re trying to look through the center of the multifocal lens or any of the segments,” he explained. “Make Retinal - from page 45 associated with the surgery itself.” Dr. Hariprasad agreed that wet ARMD patients need to be well controlled before considering cataract surgery. He stressed the importance of teaming up with a retina specialist in cases where there is even a chance of wet ARMD, such as if there is a hazy view to the back of the eye or the OCT does not look normal. “If the patient has wet macular degeneration or any other vitreomacular pathology, you’ll be kicking yourself when the patient does not see well after cataract surgery,” Dr. Hariprasad said. These patients must be nicely stabilized on anti-VEGF therapy before they can safely undergo cataract surgery, he stressed. For patients with wet ARMD who have stabilized, he recommended doing cataract surgery in conjunction with the Avastin (bevacizumab, Genentech) or Lucentis injection. “In my opinion, 2 weeks after the Lucentis or Avastin injection is the perfect time to get the cataract out,” Dr. Hariprasad said. “I think that’s when we have the maximal effect of the injection and we still have some drug onboard.” In all vulnerable ARMD patients, Dr. Hariprasad also recommended prophylaxis for cystoid macular edema with a new generation non-steroidal, as well as a steroid before and after cataract surgery to optimize outcomes. Lens considerations When it comes to lens choice, Dr. Hariprasad thinks that because there may be an oxidative stress component to ARMD, a yellow IOL may be of some benefit to patients with the disease. “We need stronger evidence regarding this, but if given the choice, there are suggestions that the blue light-filtering IOL may be beneficial to patients with ARMD to help decrease oxidative stress to the macula,” Dr. Hariprasad said. On the other side of the coin, he would be cautious with multifocal IOLs. “I think that you may not recognize the full potential of these great IOLs in a patient with macular degeneration,” he said. Likewise, Dr. Mruthyunjaya is very wary of these in moderate to advanced ARMD patients, knowing the propensity of many to develop neovascular disease in the future with a drop in paracentral function. He worries that not only is this lens not designed to deal with an atypical central macular, but it may alter the patient’s ability to use low vision-assisted devices in the future. Overall, Dr. Hariprasad stressed the need for anterior segment and retinal specialists to communicate on this. “I would encourage all cataract surgeons to speak to their retina surgeon of choice and ask for their recommendations,” he said. EW Editors’ note: Dr. Hariprasad has financial interests with Alcon (Fort Worth, Texas, USA/Hünenberg, Switzerland), Allergan (Irvine, Calif., USA), Bayer (Leverkusen, Germany), Genetech, OD-OS (Teltow, Germany), and Opgos. Dr. Mruthyunjaya has no financial interests related to this article. Contact information Hariprasad: 773-331-5900, retina@uchicago.edu Mruthyunjaya: 919-672-4450, prithvi.m@duke.edu sure that spot is very focused on the retina, and deliver that spot safely.” One tip that could help with visualization is to position the patient’s head so that his nasal bridge is not in the way during subsequent laser treatments, allowing you to easily access the nasal side with a vitrectomy probe and any other instruments used. “Usually, if we’re doing a procedure that involves peeling, we would like the head to be as straight as possible so it would be easy to focus on the macula and safely peel the membrane and not tilt the head beforehand,” he explained. “This step is even more important if the patient has a multifocal lens. The head has to be straight up, because in this case, you have to focus through the center of the multifocal IOL to be able to safely peel.” EW Editors’ note: The doctors interviewed have no financial interests related to this article. Contact information Loewenstein: john_loewenstein@meei.harvard.edu Mahmoud: thmahmoud@yahoo.com Telander: david.telander@yahoo.com