Eyeworld

EW CATARACT 34 December 2017 Cataract editor's corner of the world by Rich Daly EyeWorld Contributing Writer said. "So she wasn't looking for a multifocal lens; she was looking for good distance vision. She gave me a thousand reasons why she couldn't wear glasses anymore, and I started to think I was going to have a hard time meeting her expectations, but I like challenges." The patient's uncorrected vision was count fingers in the right eye and 20/200 in the left eye. The preoperative visual acuity of her right eye was 20/100 with a manifest refraction of –15.25 +1.50 axis 130. Her left eye was similarly myopic with a manifest refraction of –9.25 +1.50 axis 170, resulting in visual acuity of 20/80 –1. Slit lamp biomicroscopy re- vealed dense cataracts in both eyes, with 4+ nuclear sclerosis and 3+ cortical changes in the right eye and 3–4+ nuclear sclerosis with 2+ corti- cal changes in the left eye. "During the preop evaluation, we obtained the usual lens calcula- tions and corneal topography," Dr. Miller said. "We use a Pentacam [Oc- ulus, Arlington, Washington] to do corneal tomography, from which we derive corneal topography values." The patient had about 2.50 D of corneal cylinder in the 115-degree meridian in total corneal power, which included 3 D on the anterior surface. Dr. Miller planned surgery with a temporal corneal incision at 180 degrees, and the software he used calculated the best orientation for the toric lens implant. The AcrySof Toric Calculator (Alcon, Fort Worth, Texas) conclud- ed the total corneal cylinder values best fit the use of an SN6AT6 toric intraocular lens (Alcon) oriented at 112 degrees. Dr. Miller performed femtosec- ond laser-assisted cataract surgery on the right eye and used the ORA intraoperative wavefront aberrome- ter (Alcon) to confirm the spherical power of the lens at 12.0 D. "I don't use ORA much for cylinder orientation because I find it finicky with regard to how much it says to rotate a lens, and toric IOLs are difficult to rotate with balanced salt solution in the eye. For this patient, I implanted an SNTA6 12.0 D lens and oriented the lens at 112 degrees, which is where the software said to put it," Dr. Miller said. Complicated case: Fixing a small spherical error I n this month's "Cataract editor's corner of the world," we are lucky to have Kevin M. Miller, MD, highlight a chal- lenging cataract case that not only deals with a difficult refractive issue but also a difficult patient personality. Dr. Miller initially walks us through choosing a lens for a highly myopic patient with high corneal astigmatism and high expectations. After a relatively good out- come, the patient is not happy. She wants "perfect" vision, and sometimes perfect is the enemy of good. Dr. Miller shares potential scenarios for correcting a refractive surprise and his final treatment decision. Read on to see how this story ends. Rosa Braga-Mele, MD, Cataract editor Preop display for this patient Preop toric calculation Source: Kevin M. Miller, MD Cataract surgeon describes his approach in assessing and addressing a small post-cataract surgery spherocylinder equivalent refractive error A key question that can arise after cataract surgery is how to tune up a small spherocylinder refractive error. Kevin M. Miller, MD, pro- fessor of clinical ophthalmology, Kolokotrones chair in ophthalmol- ogy, and division chief for cataract and refractive surgery, Department of Ophthalmology, David Geffen School of Medicine, University of California, Los Angeles, described his approach in a case of postop refractive error of –1.50 +1.00 axis 175. The case involved a 73-year-old woman with cataracts in both eyes, who was myopic with astigmatism, and wore glasses and contact lenses. "She waited until she had bad cataracts to come in. She didn't want to wear glasses at all for distance vision and didn't mind if she had to wear glasses for reading," Dr. Miller Surgery was uneventful and at 2 weeks postop, his final assessment found an uncorrected visual acuity of 20/50 –1 vision in the eye. "Compared to preop it was better, but compared to where we wanted to be, it was not very good," Dr. Miller said. Challenge The lens was oriented at 108 degrees and only 4 degrees from the targeted 112 degrees. Despite that, the pa- tient had a modest manifest refrac- tion error of –1.50 +1.00 axis 175. "She was a little myopic, to the tune of about 1.00 D, and she

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