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EW NEWS & OPINION 9 T he American Society of Cataract & Refractive Surgery and the American Society of Ophthalmic Administrators announced that the 2015 ASCRS•ASOA Sympo- sium & Congress will be held jointly with the Latin American Society of Cataract and Refractive Surgeons (LASCRS/ALACCSA-R). The joint meeting will be held April 17–21, 2015, in San Diego. "ASCRS is a truly international organization. As many as 40% of our membership come from countries February 2014 Corneal biomechanics: Patterned corneal CXL for astigmatism Ibrahim Seven, MS, Abhijit Sinha Roy, PhD, William J. Dupps Jr., MD, PhD Investigators set out to determine whether corneal astigmatism can be altered by selective corneal stromal stiffening. They also considered how this might be affected by treatment orientation as well as the pattern and material model com- plexity in computational models informed by the specific patient measurements. In the study, 3D corneal geometries from 10 patients with astigmatism ranging from 1.22 to 3.92 diopters were considered. When 4 potential treatment patterns were tried, investigators found that the linear bow tie pattern resulted in the greatest mean reduction of astigmatism, at 1.08 D. Corneal stiffness was assumed to be 2 times that of normal. Investigators determined that using a fiber- or depth-dependent model did not affect mean astigmatism significantly. Investigators concluded that with patterned collagen crosslinking, clinically significant reductions in astigmatism were possible. The effective stiffening pattern used, treatment orientation, and patient-specific geometry all affected the treatment magnitude. Corneal biomechanics: Biomechanical effects of small incision lenticule extraction and LASIK Abhijit Sinha Roy, PhD, William J. Dupps Jr., MD, PhD, Cynthia J. Roberts, PhD How might femtosecond lenticule extraction compare to traditional LASIK? Investigators considered how corneal stress fared with each of these techniques. With LASIK a traditional flap was created and excimer laser ablation performed. With the other technique, the femtosecond laser created a lenticule with a shape programmed to refractive correction. This was then removed through a small incision. Investigators found that there was similar stress distribution with the two techniques. They determined that with LASIK, flap stress was consistently reduced, but residual stromal bed stress increased compared to the geometry analog model. Investigators found that in the LASIK model an increase in flap thickness resulted in a greater increase in residual stromal bed stress than with the small incision lenticule approach. Investigators concluded that there was similar stress distribution between the two approaches. However, they deter- mined that there may be less biomechanical risk to the residual bed of some corneas with use of small incision lenticule extraction. With the lenticule extraction approach, deeper correction in the stroma may be possible, without an increase in ectasia risk. Corneal biomechanics: Accelerated and conventional CXL Minoru Tomita, MD, PhD, Mariko Mita, MD, PhD, Tukezban Huseynova, MD In this study, the aim was to see how accelerated corneal collage crosslinking compared to the conventional approach for eyes with keratoconus. Of the 48 eyes included here, 30 underwent accelerated crosslinking, and the remaining 18 were treated with the conventional approach. With the accelerated approach eyes were presoaked with riboflavin for 15 minutes. Then they were treated for 3 min- utes using ultraviolet-A light at 30 mW/cm. 2 Meanwhile with the conventional approach they were presoaked for 30 minutes with riboflavin and then had UVA light applied at 3 mW/cm 2 for another 30 minutes. Postoperatively, at 1-year follow up, investigators determined that there was no statistically significant difference between the two procedures in uncorrected or corrected distance visual acuity or in manifest refraction spherical equivalent. Postoperative readings from Pentacam Scheimpflug imaging, a dynamic Scheimpflug analyzer, or the Ocular Response Analyzer didn't find any statistically significant differences. Investiga- tors determined that there was a pronounced demarcation line seen in both groups postoperatively as well as similar morphologic changes. Investigators concluded that both procedures were safe and effective. However since acceler- ated crosslinking is such a fast procedure, they viewed this as more beneficial for both patients and surgeons. In the journal … June 2014 May 2013 June 2014 by Cindy Sebrell ASCRS•ASOA Director of Marketing and Communications Next ASCRS•ASOA meeting to be jointly held with LASCRS/ALACCSA-R ASCRS update continued on page 10 around the world, and about 50% of those who attend the ASCRS•ASOA Symposium & Congress are from countries other than the U.S.," said Richard A. Lewis, MD, ASCRS president. "I am pleased to announce that the 2015 ASCRS•ASOA Symposium & Congress in San Diego will be a joint meeting with the Latin American Society of Cataract and Refractive Surgeons," Dr. Lewis said. "This is an exciting and powerful partnership that will be sure to help advance our profession. William De La Peña, MD Richard A. Lewis, MD 2-10 O&C_EW June 2014-DL_Layout 1 6/3/14 12:09 PM Page 9

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