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EW REFRACTIVE SURGERY 58 October 2015 possible to maximize results. "I think that the ORA should be strongly considered in refractive cataract surgery," she said. Also, it's important for surgeons to look at their outcomes and be open-minded about new technologies. "Addition- al research is going to continue to guide us," Dr. Hatch said. EW Editors' note: Dr. Hatch has no finan- cial interests related to this article. Contact information Hatch: Kathryn_Hatch@MEEI.HARVARD.EDU by Maxine Lipner EyeWorld Senior Contributing Writer tioners have to get used to such as making sure that the pressure is ap- propriate, that there are no bubbles, and that the lid speculum isn't in the way. "I do think that there is a bit of a learning curve with it," she said. "It's important for surgeons to use it on their vanilla cataracts first." Once they get used to it, they can begin using it on more complicat- ed cases involving toric lenses and post-refractive patients, as well as those with long axial lengths. Dr. Hatch hopes that practi- tioners come away with the message that they need to do everything terior contribution, she said, adding that not only can this help with choosing the power but it can also aid in aligning the implant. For this retrospective compara- tive trial, in 37 eyes IOL power and alignment were determined prior to surgery with automated keratom- etry, optical biometry, and the aid of an online calculator before these were later refined using intraoper- ative aberrometry, Dr. Hatch said. Meanwhile, the 27 eyes in the toric calculator group underwent each of these steps with the exception of the use of the intraoperative aberrometer. After surgery, investi- gators found that the mean residual refractive astigmatism for those in the intraoperative aberrometry group was just 0.46 D compared with 0.68 D for those in the other group. In addition, they determined that there was a 75% reduction in cylinder postoperatively for those in the aberrometry group versus 57% for those in which the toric calcula- tor was used. One surprising finding was how often investigators needed to change the lens power in the operating room based on aberrometry find- ings. "We changed the spherical power and the toric power anywhere from 30–35% of the time," she said. "I think this shows that our tradi- tional methods aren't always accu- rate and that it's very useful to have additional measuring techniques during surgery." Meeting expectations Dr. Hatch believes the outcomes here indicate that use of intraop- erative aberrometry can improve results. "It will hopefully reduce the amount of postoperative enhance- ment that we have to do," she said. In this the era of refractive cataract surgery, patients expect excellent refractive outcomes. "If [surgeons are] doing refractive cataract surgery, they should strongly consider using techniques that can maximize their results," she said. Still, she does find that the ORA has some potential drawbacks such as time and cost. In addition, there are special techniques that practi- How this affects toric cases P ractitioners today try to do everything they can to position lenses as accurately as possible. But can meticulous calcula- tions compete with intraoperative aberrometry? A study published in the April 2015 issue of the Journal of Refractive Surgery indicates that intraoperative aberrometry can lend an edge, according to Kathryn M. Hatch, MD, Massachusetts Eye and Ear, Waltham, Mass., and faculty ophthalmologist, Harvard Medical School, Boston. When investigators set out to determine the value of intraopera- tive aberrometry for implantation and positioning of toric lenses, they found that those undergoing toric lens placement aided by intraocular aberrometry were 2.4 times more likely to have less than 0.5 D of residual refractive astigmatism re- maining compared with those cases where standard toric online calcu- lations were used without aberrom- etry, she reported. Dr. Hatch main- tains that such accuracy is vital. "If we're off by a very small amount, we can start to lose significant effect of the toricity of the lens, so it's extremely important that we're on target with the axis and power of the toric lens implant," she said. Comparing approaches Investigators here wanted to consid- er how important an intraoperative aberrometry device such as the ORA (Alcon, Fort Worth, Texas) is and take a closer look at what role it plays with toric lenses, Dr. Hatch explained. Many of the ways to measure astigmatism in the office only look at the anterior cornea, she pointed out. "We have learned a lot from Doug Koch [MD], and others that posterior cornea contribution does contribute to overall astigma- tism," Dr. Hatch said. "The ORA can give us real-time information about the astigmatism in the eye after the cataract is removed and can give us better information about the power and axis of astigmatism." This isn't always the same based on the pos- The power of intraoperative aberrometry The ORA can give real-time information about astigmatism after the cataract is removed. After toric IOL rotation, ORA indicates that the lens is in position with no additional rotation necessary. Source: Kathryn M. Hatch, MD

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