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EW MEETING REPORTER 160 October 2016 Reporting from ASCRS YES ACT, September 24–25, Denver Reporting from ASCRS YES ACT Surgical management of astigmatism Surgical management of astigma- tism is one way to help achieve a refractive outcome more patients are expecting at the time of cataract surgery. "We are operating in an era where it's refractive cataract surgery; it's not just cataract surgery," said Leela Raju, MD, New York. "And patient expectations are high." Dr. Raju said estimates suggest that 40% of cataract patients have up to 1 D of astigmatism. Overall, the goal after refractive cataract surgery is less than 0.5 D of residual astigmatism. Managing astigmatism surgi- cally starts with determining its magnitude and axis preoperatively. Jonathan Rubenstein, MD, Chicago, said he thinks the best test for axis is using IOLMaster (Carl Zeiss Meditec, Jena, Germany) or LENSTAR (Haag-Streit, Koniz, Switzerland) and topography. The best test for magnitude, he said, is manual keratometry and IOLMaster and LENSTAR. Astigmatism measured only an- teriorly does not take into account the whole cornea, Dr. Raju pointed out in her presentation. To account for the role of posterior corneal astigmatism, Dr. Raju said using no- mograms and online calculators that adjust for the posterior cornea can make calculations more accurate. Surgeons on the panel had different benchmarks to determine whether to perform limbal relaxing incisions (LRIs) or implant a toric IOL. While LRIs can theoretically be used to correct up to 3 D of astigma- tism, some on the panel said they only perform LRIs on patients with up to 1.25 D to 1.75 D of astigma- tism. In addition, patients who are well suited for LRIs ideally have regular, with-the-rule astigmatism. LRIs can be made manually or with a femtosecond laser. Sumit "Sam" Garg, MD, Irvine, California, offered some pearls for femtosecond laser LRIs. One included avoiding going too peripherally, which can lead to tags that are more difficult to dissect. He also said that he often will not open LRIs on the table right away, waiting to open them depend- ing on the patient's outcome. But does the laser result in bet- ter outcomes compared to manual LRIs? Dr. Garg said based on the current data the jury is still out, but he thinks it probably results in sim- ilar outcomes, and the laser might have some benefits depending on the patient. For manual LRIs, Amy Lin, MD, Salt Lake City, said she avoids doing them in patients with kera- toconus, though she knows other surgeons have done so with success. She would consider manual LRIs in a case of irregular astigmatism if it is mild. For marking the patient, Dr. Lin said it's important to have the patient sitting up. She uses "low tech," manual marking at 3:00 and 9:00, but noted the free toriCAM app, which uses a smartphone cam- era, can be useful in marking the axis preoperatively as well. For patients with more astigma- tism, a toric IOL might be the better option for correction. Similar to LRIs, accurate mea- surements of the corneal astigma- tism are imperative. "What you're looking for is congruence," said Zachary Zavodni, MD, Salt Lake City. Understanding the current cal- culators and nomograms available can also help ensure good outcomes. Industry-sponsored calculators and the Holladay IOL Consultant (Holl- aday Consulting, Bellaire, Texas) are options, but they do not account for posterior corneal astigmatism. Dr. Zavodni said the Baylor nomogram can be applied to account for that. The Abulafia-Koch formula includes a keratometry adjustment, and the Barrett Toric Calculator includes pre- dicted effective lens position, spheri- cal power, and adjusted keratometry, Dr. Zavodni said. If there is a refractive surprise post-toric IOL, Dr. Garg said one should first look at the ocular surface and treat any issues there. If maxi- mizing ocular surface health doesn't improve the outcome, options to correct the error, depending on the

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