EyeWorld Asia-Pacific June 2018 issue

June 2018 EWAP FEATURE 19 Views from Asia-Pacific CHEE Soon Phaik, MD Senior Consultant, Professor Singapore National Eye Centre 11 Third Hospital Avenue, Singapore 168751 Tel. no. +6562277255 Fax no. +6562263395 chee.soon.phaik@singhealth.com.sg M y experience is mainly with the Symfony lens. Achromatic technology together with the steps on the EDOF IOL induce diffraction of light, creating an elongation of focus, resulting in an extended range of vision. With a light energy transmission of 91% higher than that of trifocal IOLs, it gives good contrast sensitivity, akin to that of monofocal IOLs. This IOL provides a spectrum of vision ranging from distance to about 47 cm. In order to provide some degree of near vision, mini-monovision is practiced. I target –0.25 D or less for the dominant eye and –0.5 D or more for the nondominant eye. When this EDOF IOL was first launched, it was thought to be free of dysphotopsias and tolerant to astigmatism. However, our Singapore National Eye Centre IOL audit data revealed that patients experience halos and glare, with the halos being more pronounced than the glare, even when distance corrected. When compared with the trifocal IOLs, these visual phenomena were on the lower end of the spectrum. Despite the mini-monovision, some patients still had difficulty in reading and required low-add spectacles. The issue is that one is unable to predict the poor readers prior to surgery. EDOF IOLs provide “ patients with very dense or white cataracts the option of receiving a presbyopia- correcting IOL. In addition, due to the excellent light transmission, it is more tolerant of very mild macular pathology... ” - Chee Soon Phaik, MD In the initial studies, eyes with up to –1.5 D cylinder were not given toric correction and still managed well. However, in my experience, correcting the astigmatism is critical in improving the visual outcome, and my threshold for a toric implant is not different than for a trifocal IOL. These IOLs are nonetheless more forgiving of mild spherical error due to the elongated focus. This technology thus provides patients with very dense or white cataracts the option of receiving a presbyopia-correcting IOL. In addition, due to the excellent light transmission, it is more tolerant of very mild macular pathology, such as the occasional drusen or mild epiretinal membrane and mild glaucomatous optic neuropathy. An unhealthy ocular surface despite treatment however is a contraindication as glare and halos are accentuated. Thus, for patients who wish for a presbyopia-correcting IOL, I prefer EDOF to trifocal IOLs in the presence of mild optic nerve or macular pathology, or eyes not measureable with the optical biometer and patients who are less tolerant to halos and glare. They are counseled regarding mini-monovision and the possibility of still needing reading glasses. Editors’ note: Dr. Chee receives travel support and speaks for Johnson & Johnson Vision. John S.M. CHANG, MD Hong Kong Sanatorium and Hospital 8/F Li Shu Pui Block, Phase II, 2 Village Road, Happy Valley, Hong Kong johnchang@hksh.com W e have two EDOF lenses available, the Symfony and Oculentis Comfort (Berlin, Germany) with +1.5 ADD. The more rings you have, the stronger the ADD, the more halo and glare. The EDOFs have the advantage of minimal halo and almost no glare or drop in contrast sensitivity. Driving and time spent in dark environment are important issues. In big cities where most people don’t drive or rarely go out at night, I start with the trifocal right away in the non-dominant eye. If they don’t have any problem, I use the same lens for the other eye. If they have some concerns, I would use the EDOF in the dominant eye. “ The more rings you have, the stronger the ADD, the more halo and glare. The EDOFs have the advantage of minimal halo and almost no glare or drop in contrast sensitivity. “ Driving and time spent in dark environments are important issues. ” - John S.M. Chang, MD If they drive, I use the Symfony or Oculentis Comfort (+1.5 ADD) in the dominant eye. If they are happy with their near (usually hyperopes), I use the same lens. If they want more near, I will use a trifocal lens. In Hong Kong, which is multicultural, it is important also to determine their reading and computer distance—Caucasians are taller and read a lot further away than Asians. The EDOF targeted for plano in the dominant eye and slight myopia –0.75 D in the non-dominant eye is often good enough for taller people. Asians are generally shorter and hold their reading material much closer. If good night vision is important, I often use the EDOF and aim for plano in the dominant eye, and aim for –1.5 D in the non-dominant eye. However, I have to make sure they can tolerate monovision in my preop assessment. For post-myopic LASIK patients, EDOF can tolerate anisometropia and astigmatism better than MFIOL, but there is not enough evidence whether it will work well or not. The early results are encouraging. Patients should be warned that they may have significant halo and glare. Editors’ note: Dr. Chang receives a lecture honorarium from Johnson & Johnson Vision. continued on page 20