EyeWorld Asia-Pacific December 2016 Issue

35 EWAP CATARACT/IOL December 2016 Dr. Bissen-Miyajima concluded that the 3-year results from this new material show good visual acuity, less PCO, and less glistening. Rupert Menapace, MD , Vienna, Austria, spoke about rotational stability, which he said is crucial when you use a lens platform for toric lenses. If you misalign a lens by 10 degrees, you lose one-third of the corrective power, he said. If you mis- align by 30 degrees, you lose all the corrective power, and greater than that there will be significant rotation of the axis, Dr. Menapace cautioned. Causes of toric IOL misalign- ment could be attributed to prima- ry malpositioning, Dr. Menapace said. This could be from erroneous calculation of the target axis, erro- neous or imprecise marking of the target axis, or imprecise alignment of the toric IOL with axis marks. Secondary rotation of the toric IOL in the capsular bag could also cause misalignment. In the literature, a lot of infor- mation on rotational stability shows methods regarding how physicians can assess the position of the lens and when they start controlling the “ Results indicated that eyes with the Vivinex TM showed a lower rate of PCO and lower density of the posterior capsule compared to the control group. Additionally, results showed that glistenings were reduced in the Vivinex TM eyes compared to the control group. ” – Hiroko Bissen-Miyajima, MD, PhD Suhas Haldipurkar, MD, Hiroko Bissen-Miyajima, MD, Soon Phaik Chee, MD, Rupert Menapace, MD, and Gerd Auffarth, MD, presented at a symposium sponsored by HOYA Surgical Optics at the 2016 Asia-Pacific Association of Cataract & Refractive Surgeons meeting. Source: HOYA cannot ignore the size of the pupil, he said, because a larger pupil will deteriorate the quality of vision. Additionally, total aberrations of the eye increase three-fold between the ages of 20 and 70. When implanted in the capsular bag, the IOL center is typically 0.36 mm from the visual axis, which makes the IOL slightly decentered on the visual axis, Dr. Haldipurkar said. This natural physiologic mis- alignment degrades the image quali- ty with traditional negative aspheric IOLs in spite of the excellent optics, he said. Dr. Haldipurkar then discussed the HOYA IOL with patented Aspheric Balanced Curve Design (ABC Design) and results from stud- ies comparing that IOL to others. This IOL performed “equally well” in eyes with angle alpha greater than 0.4 mm, he said. The IOL is also less affected by decentration, Dr. Haldipurkar added. The IOL provides unique control of high- er order aberrations to reduce the effect of decentration, he said, and it provides minimal distortion in the center, where it really matters. Sponsored by HOYA Surgical Optics rotation baseline, Dr. Menapace said. It’s necessary to have this informa- tion on rotational stability at the end of surgery while the patient is still on the table, he added. How- ever, published data on rotational stability are incomplete and ir- relevant, Dr. Menapace said. True rotational stability is actually worse than published, he said, and outliers with almost all “big players” on the market can occur. What counts is the positional change from the end of surgery to 1 month, not the devi- ation from the intended axis or from 1 hour, 1 day, or even later. “What counts [are] outliers and not mean values and standard deviations,” he said. It’s especially important to be- gin looking at this while the patient is still on the table because in many published studies, the first hour after surgery is disregarded, Dr. Menapace said, and this is when rotations are most frequent and pronounced. Looking at data at 4 to 6 months on rotational stability, the Vivinex TM lens was the only product investigated that did not exhibit a single case of an outlier rotating more than 5 degrees, Dr. Menapace said. Vivinex showed an excellent rotational stability with an average of 1.54 degrees and a range of up to 5 degrees collected on 103 eyes, which is better than other tested hydrophobic lenses. Dr. Menapace added that companies must provide relevant information, and he recom- mended that surgeons minimize the need for rotation by using brands with proven rotational stability. Inform patients about possible rota- tion and possible need for surgical correction, he said. Surgeons should also optimize surgical technique by avoiding dispersive OVDs, allowing haptics to completely unfold, and flattening the chamber and leaving the eye normotonic at the end of surgery. He stressed the importance of seeing all patients at 2 weeks postop to detect any outliers and to reposition the toric IOL between 2 to 4 weeks when needed. Finally, Suhas Haldipurkar, MD , Mumbai, India, spoke about spherical aberration. There is a quest for better quality for the patient, he said. If you look at aspheric and spherical lenses, Dr. Haldipurkar said that aspheric will give better quality, but the depth of focus is slightly less. At the same time, you “ t T of PCO and lower density of the