EyeWorld Asia-Pacific September 2016 Issue

September 2016 EWAP NEWS & OPINION 71 continued on page 8 continued on page 72 calculations. For example, he found that if ultrasound speed settings are not adjusted for phakic IOL materials that are considered faster, like acrylic, the axial length is underestimated and IOL power is overestimated, thus creating a myopic error after cataract surgery. A slower material, such as silicone, without adjusted ultrasound speeds results in an overestimated axial length and underestimated IOL power, creating a hyperopic error. Phakic IOL material had a similar effect on optical biometry as well. Overall, Dr. Aramberri found the myopic lens error created by faster phakic IOL materials was negligible, but slower phakic IOL materials creating a hyperopic lens error is significant and should be corrected by adding a correcting factor. Special lecture highlighted AMD and cataract A cataract surgery symposium titled “Don’t Worry, Be Happy … Avoiding Unexpected Outcomes” featured a special lecture given by Adrian Koh, MD , Singapore. Dr. Koh, a retina specialist, spoke about how cataract surgery potentially impacts age-related macular degeneration (AMD) and vice versa. Cataracts, he said, often coexist with AMD—both are age- related conditions, with significant overlap in peak ages of occurrence. He reviewed the international classification for AMD—based on assessment of drusen characterized by size (>63 microns) and pigmentary abnormalities within two disc diameters of the fovea. He recommended that cataract surgeons review and familiarize themselves with this classification. The classification, he said, is useful because there is a direct correlation with risk for developing severe AMD. In his talk, Dr. Koh answered three common questions cataract surgeons have when encountering the conditions together. First, will cataract surgery improve vision in patients with AMD? Most patients, Dr. Koh said, report significant improvement not just in visual acuity but in quality of life scores—comparable to those without AMD. Patients with early to intermediate AMD are likely to achieve reasonable gains in visual acuity after cataract surgery. Meanwhile, though patients with late AMD might not enjoy the same gains, they may improve in terms of color discrimination, contrast, and peripheral vision. In addition, dense cataracts may obscure accurate assessment of the macula, especially in eyes with high risk of developing choroidal neovascularization (CNV). Will cataract surgery make AMD worse? Dr. Koh said that some surgeons might think so because inflammation has been implicated in the pathophysiology and progression of AMD, but the Age-Related Eye Disease Study (AREDS) found no difference in risk of developing advanced AMD between phakic and non-phakic eyes. He cited other studies that came to the same conclusion but also showed significantly better visual acuity and higher quality of life scores among AMD patients who undergo cataract surgery. Are there any precautions to be taken to optimize surgical outcomes? “There is no evidence that cataract surgery, if done properly, will aggravate AMD,” Dr. Koh said. “But this does not mean that we will not try our utmost to optimize outcomes.” Dr. Koh said surgeons should stabilize wet AMD before surgery. In terms of choice of IOL, he thinks it is reasonable to use yellow-tinted, blue-blocking IOLs despite lack of trial evidence. Meanwhile, it is best to avoid multifocal IOLs since they reduce contrast and affect the view of the macula. Dr. Koh further recommended aggressive control of inflammation in patients with active wet AMD, beginning NSAID administration preoperatively, followed by NSAIDs postoperatively, and close surveillance of high-risk patients. Phaco technologies and techniques The “Phaco Technologies and Techniques” symposium highlighted both techniques for removing cataracts and the technologies most relevant for this. The session also included a special lecture by Sanduk Ruit, MD , Kathmandu, Nepal, on “Logistics of Phaco for High Volume Community Cataract Surgery.” Viraj Vasavada, MD , Ahmedabad, India, presented on optimizing cataract surgery in post-refractive surgery eyes. Any refractive surgery has altered the corneal profile, she said, so there’s a change in asphericity and aberrations. This would affect IOL selection, and could pose potential postoperative issues. She also offered several pearls for IOL selection, including the need to counsel about both residual refractive error and the possibility of postoperative glares and halos. She also said to avoid multifocal IOLs in these patients. In his presentation, Johan Hutauruk, MD , Jakarta, Indonesia, shared seven habits in highly effective biometry. First, he said to avoid applanation and use the immersion. He also suggested