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astigmatism, and the cylinder induced by the cataract incision are all considered with intraoperative aberrometry," Dr. Donnenfeld said. Overall, Dr. Donnenfeld views astigmatism management as the number one limiting step for most ophthalmologists in achieving opti- m al refractive outcomes—which he thinks the femtosecond can help to overcome. "With new technology and new interest I believe that we can improve outcomes in a signifi- cant way to achieve emmetropia in patients undergoing cataract surgery," he concluded. EW Editors' note: Drs. Alpins and Stamatelatos have financial interests with the Assort.com web calculators and the Assort.com surgical manage- ment systems. Dr. Stamatelatos also has financial interests with ASSORT Surgical Management Systems (Victoria, Australia). Dr. Donnenfeld has financial interests with Abbott Medical Optics, Alcon, Bausch + Lomb (Rochester, N.Y.), and WaveTec. Dr. Holladay has financial interests with A cuFocus (Irvine, Calif.), Alcon, Abbott Medical Optics, Oculus, Visiometrics (Terrassa, Spain), WaveTec, and Carl Zeiss Meditec (Jena, Germany). Dr. Koch has financial interests with Alcon and Abbott Medical Optics. Contact information A lpins: alpins@newvisionclinics.com.au Donnenfeld: ericdonnenfeld@gmail.com Holladay: holladay@docholladay.com Koch: dkoch@bcm.tmc.edu Stamatelatos: george@newvisionclinics.com.au March 2014 xxx Partners In Vision is the leader in Optical Dispensary Development + Management for one very simple reason; Our reputation is on the line too. Tat's why we're known for superior customer service, atention to detail, responsive inventory management and patient education. How well are you protecting your brand? PartnersInVision.com Since 1999 WHAT'S YOUR REPUTATION WORTH? O P T I C A L D I S P E N S A R Y M A N A G E M E N T Nomogram: By the numbers E ven with new technology, improving outcomes often comes down to old-fashioned nomograms. Dr. Donnenfeld described his nomogram, which is one of the most commonly used, as one that he developed seven years ago for doing manual limbal relaxing incisions. He views the nomogram, which can be found at www.lricalculator.com, as a very simple one. While this can now be applied to femtosecond laser incisions, Dr. Donnenfeld pointed out that since these incisions are done closer to the visual axis than manual ones, they are more powerful. "We found that by simply taking the manual LRI calculator and reducing the nomogram by 33%, we achieve very good results with the lasers," Dr. Donnenfeld said. The nomogram also allows practitioners to compensate for the cataract incisions that they make at the same time. With LRIs, a common mistake for clinicians is that they make these at the site of the preoperative cylinder and don't consider the change in the cylinder resulting from the phacoemulsification incision. To compensate for this, Dr. Donnenfeld changes the axis by 15 to 20 degrees. With the nomogram he finds that he routinely attains about a 70% improvement in cylinder. "With the ability to titrate the incisions we have very few overcorrects, where we shift axes, so that has been a nice improvement in our results," Dr. Donnenfeld said. "These results, in my estimation, are about 20% better than those that are achieved with manual LRIs." Dr. Holladay commented that the nomogram he had developed for the Verion system combined the Donnenfeld modi7cations stated above as well as the Koch, Nichamin, and other LRI nomograms to include all of the factors that were not present in any one. These factors included steepness of the cornea, corneal diameter, thickness of the peripheral cornea, axis of astigmatism (WTR, ATR, or oblique), surgically induced astigmatism from the primary cataract incision and age, as well as magnitude of preoperative astigmatism. The femtosecond precision of the necessary arc length to 0.1 mm and registration of the laser with the preoperative measurements are also factors explaining the improvement, so it is not surprising the femtosecond AK results were competitive with toric IOLs and intraoperative aberrometry and superior to manual LRIs, he said. 108-125 Feature_EW March 2014-DL2_Layout 1 3/7/14 10:47 AM Page 115