Eyeworld

49 EW RESIDENTS February 2016 92% R E T EN T ION 92% * Parasol® TO ORDER: 866-906-8080 customersupport@beaver-visitec.com odysseymed.com or beaver-visitec.com We've taken the worry out of plug retention, so you can concentrate on patient retention. The Parasol® Punctal Occluder trumps the competition with an unprecented 92% retention rate. Use the Parasol® Punctal Occluder, designed for easy insertion and guaranteed to stay put. STAYS PUT Rely on something that BVI, BVI Logo and all other trademarks (unless noted otherwise) are property of a Beaver-Visitec International ("BVI") company © 2016 BVI * "Plugs Reduce Dry Eye Symptoms, Improve Vision", Craig McCabe, M.D., Review of Ophthalmology, 2009. when each method is used. A pro- spective, controlled trial using the proposed methods to select the toric IOL and measure the true residual astigmatism and visual acuity of each method would help eliminate potential confounding variables. Further, the paper does admit that a weakness of the study is that the to- ric IOL cylinder power at the corneal plane was calculated with the merid- ional analyses method based on the Holladay 1 formula and not directly, which could induce a confounding factor in the analysis. Despite these limitations, the study shows promising results for the authors' proposed method of using vector summation to incorpo- rate posterior corneal tomography into anterior corneal measurements in choosing toric IOL power and axis. They further validated the Baylor nomogram in improving re- sidual refractive outcomes. We look forward to larger, prospective studies to provide more robust information on the outcomes of these methods as well as the Barrett toric calculator, as we suspect that the inclusion of posterior corneal parameters will soon be routine in the ever-advanc- ing refinement of IOL selection. EW References 1. Agresta B, et al. Visual acuity improvements after implantation of toric intraocular lenses in cataract patients with astigmatism: a system- atic review. BMC Ophthalmol. 2012;12:41. 2. Entabi M, et al. Injectable 1-piece hydro- philic acrylic toric intraocular lens for cataract surgery: efficacy and stability. J Cataract Refract Surg. 2011;37:235–40. 3. Mingo-Botin D, et al. Comparison of toric intraocular lenses and peripheral corneal relaxing incisions to treat astigmatism during cataract surgery. J Cataract Refract Surg. 2010;36:1700–8. 4. Kim MH, et al. Long-term efficacy and rotational stability of AcrySof toric intraocular lens implantation in cataract surgery. Korean J Ophthalmol. 2010;24:207–12. 5. Koch DD, et al. Contribution of posterior cor- neal astigmatism to total corneal astigmatism. J Cataract Refract Surg. 2012;38:2080–7. 6. Koch DD, et al. Correcting astigmatism with toric intraocular lenses: effect of posterior corneal astigmatism. J Cataract Refract Surg. 2013;39:1803–9. 7. Holladay JT, et al. Calculating the surgi- cally induced refractive change following ocular surgery. J Cataract Refract Surg. 1992;18:429–443. 8. Holladay JT, et al. Analysis of aggregate sur- gically induced refractive change, prediction error, and intraocular astigmatism. J Cataract Refract Surg. 2001;27:61–79. Contact information Wayman: laura.l.wayman@Vanderbilt.Edu " Despite these limitations, the study shows promising results for the authors' proposed method of using vector summation to incorporate posterior corneal tomography into anterior corneal measurements in choosing toric IOL power and axis. "

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