Eyeworld

57 EW REFRACTIVE November 2018 revealed that both phakic IOLs achieved a remarkable index of refraction, with an efficacy index of 0.90±0.26 and a mean safety index of 1.19±0.29. The efficacy index was not statistically different between the two lenses (P=.058), and refrac- tion was stable during the follow up. 3 "Our study showed that both of the phakic IOLs did an excellent job with a remarkable similarity. There was a small trend toward undercor- rection in the ICL, but we learned this was due to the abnormal surface to sulcus distance especially in moderate to advanced keratoconus. Therefore, we think that the indi- cations for toric PIOLs in irregular corneas include patients with stable astigmatism, patients with a low grade of irregular astigmatism, HOA <2.5 µm in the central 4 mm of the cornea, patients whose BSCVA is >20/40, cases with coma aberration lower than 1.5 µm, usually grade I and II (RETICS) maximum kerato- conus, and the same guidelines for post-keratoplasty. A careful endo- thelial evaluation is mandatory," he said. EW References 1. Vega-Estrada A, et al. Outcome analysis of intracorneal ring segments for the treatment of keratoconus based on visual, refractive, and aberrometric impairment. Am J Ophthalmol. 2013;155:575–584. 2. Alio JL, et al. Keratoconus-integrated characterization considering anterior corneal aberrations, internal astigmatism, and cor- neal biomechanics. J Cataract Refract Surg. 2011;37:552–68. 3. Alio JL, et al. Comparison of iris-claw and posterior chamber collagen copolymer phakic intraocular lenses in keratoconus. J Cataract Refract Surg. 2014;40:383–94. Editors' note: Dr. Alio has financial interests related to his comments. Contact information: Alio: jlalio@vissum.com keratoconus grade I and some with grade II). 1 He explained, however, that brain aberration compensation could differ significantly among patients. In another study, he and his coinvestigators tried to qualify vari- ables involved in the degradation of vision in 776 eyes of 507 keratoco- nus patients. They found that there could be acceptable levels of vision in highly aberrated corneas. Vision could be adequate for functional purposes in many patients and visu- al limitations could be explained by different alterations in these cor- neas, according to the retrospective case series. 2 "Based on our experience, we can say that to successfully treat regular astigmatism with toric PIOLs in an irregular cornea, only cases with stable astigmatism should be considered," he said. "We perform a thorough analysis of the central 4 mm of the topography and avoid corneas with high irregularity. Pa- tients whose BCVA is 20/40 or better can qualify for this operation. For keratoconus patients, usually grades I and II qualify. It is better to include cases with not very high coma aber- ration, not more than 1.5–2 µm, and to avoid patients who need RGPs to achieve good VA. All these factors need to be considered together in order to make the right decision," he explained. Patients who fit the bill for toric phakic IOL implantation have a number of choices. Two op- tions—the Artiflex toric IOL (Oph- tec, Groningen, the Netherlands) and the toric ICL (STAAR Surgical, Monrovia, California)—were part of a study carried out by Dr. Alio, who compared them as part of a retrospective, comparative study for visual outcomes, predictability, and stability in keratoconic eyes. The toric iris claw lens (Artiflex) was im- planted in 20 keratoconic eyes and the toric ICL, a collagen copolymer posterior chamber phakic IOL, in 28 keratoconic eyes. The study patients had stable keratoconus grade I and II (Amsler-Krumeich). The outcomes I N S T R U M E N T S | S I N G L E U S E | D R Y E Y E | B I O L O G I C S Look to Stephens for ophthalmic instruments. © 2018 Stephens Instruments. All rights reserved. For more than 40 years, Stephens Instruments has offered a full line of premium microsurgical ophthalmic instruments. With 1000+ instruments backed by a limited lifetime warranty, you can feel confident in the high quality and superior service from Stephens. Stephens – more than instruments. Stephens Instruments | 2500 Sandersville Rd | Lexington KY 40511 USA Toll Free ( USA ) 800.354.7848 | info@stephensinst.com | stephensinst.com ST5-7035 Utrata Capsulorhexis, 23 Ga Titanium Forceps S9-2060 Henderson Degree Guage S4-1715 SMILE Double Ended Dissector with Lenticule Manipulator

• Blank Page
• Blank Page (1)