Eyeworld

EW FEATURE 33 by Michelle Dalton EyeWorld Contributing Writer Experts: PRK effective refractive surgery option for cataract surgeons If a surgeon lacks refractive training, many experts suggest using PRK over LASIK N ot every cataract surgeon has experience with surface laser vision correction procedures to correct residual refractive errors. Whether choosing PRK or LASIK, cataract surgeons can experi- ence varied learning curves. Experts weigh in on their recommendations and uses of both refractive proce- dures in these cases. ing PRK, said Uday Devgan, MD, in private practice in Los Angeles, and chief of ophthalmology, Olive View-UCLA Medical Center. "PRK is very accurate, very safe, and has a minimal learning curve," he said. "The results are excellent, particularly since these post-cataract surgery patients typically have very small residual refractions to treat, somewhere around 1 to 1.5 D—un- like doing primary PRK or LASIK in young non-cataract patients where you may be treating –6 D or –8 D." Both PRK and LASIK have short learning curves, Dr. Hoffman said, but agreed that LASIK may be more intimidating for the novice. "There are nuances to lifting the flap, and the potential complica- tions of epithelial ingrowth, diffuse lamellar keratitis, or folds can be July 2014 Keratorefractive enhancement of pseudophakes AT A GLANCE • Cataract surgeons can learn to perform refractive surgery for the correction of residual refractive errors with a minimal learning curve, experts say. • Experts interviewed suggested choosing PRK over LASIK for novice keratorefractive surgeons. • Wait until the initial cataract wound is secure (approximately 3 months) before performing LASIK enhancement surgery. This patient had a nicely performed cataract surgery with a well-centered multifocal IOL, but had residual myopia and astigmatism that limited visual quality. A small treatment with PRK enabled the patient to achieve a near plano outcome with excellent distance and near vision. Source: Uday Devgan, MD continued on page 34 Paying continued from page 31 to commit to fully optimizing patients' vision because they don't have the capability of doing either LASIK or PRK to fully enhance them," Dr. MacRae said. But a laser vision enhancement is not the only answer. Another vi- able, potentially less-intimidating option can be the use of mini-PRK, he said. With the mini-PRK tech- nique, less epithelium needs to be removed since the treatments and transition zones are relatively small, Dr. MacRae explained. "That gives the patient less pain, quicker visual recovery, and less likelihood of having problems with re-epithelialization," he said. "It's a perfect option for a cataract surgeon who wants to do a small enhancement." Dr. Schallhorn urges practition- ers to keep in mind that for residual astigmatism, an astigmatic kerato- tomy might be a good choice too. The lens could be rotated, ex- changed for a different power, or a piggyback lens can be put in, Dr. Schallhorn said. "It's not a jump right to laser vision correction," he said. Dr. Berdahl agreed that lack of access to laser vision correction is one factor hampering enhance- ments. He also thinks that some physicians are approaching pre- mium outcomes from the point of view that they ultimately want to "do no harm." "You can't do any harm by not doing anything," he said. "But you may not get the ball into the end zone either." Going forward, Dr. Berdahl thinks that use of intraoperative aberrometry and the latest genera- tion IOL calculations will help di- minish the need for enhancements. In addition, the lenses themselves may play a role. "Future technology like the Light Adjustable Lens [Calhoun Vision, Pasadena, Calif.] may make it so that we plan on building an enhancement in for everyone," he said. EW Editors' note: Dr. Schallhorn has financial interests with Abbott Medical Optics (Santa Ana, Calif.). Dr. Berdahl has financial interests with Alcon (Fort Worth, Texas) and Bausch + Lomb (Bridgewater, N.J.). Dr. MacRae has no financial interests related to his comments. Contact information Berdahl: johnberdahl@gmail.com MacRae: Scott_MacRae@URMC.Rochester.edu Schallhorn: scschallhorn@yahoo.com Overcoming learning curves It is fairly common for surgeons "who are not laser vision correction surgeons by trade" to do surface laser vision correction at TLC, said Karl G. Stonecipher, MD, director of refractive surgery at TLC, Greens- boro, N.C. "But as more surgeons begin using a docking process with cataract surgery, we're seeing more surgeons considering moving some of those patients based on their refractive error to LASIK." Dr. Stonecipher typically performs transepithelial PRK for residual myopia or residual myopic astigmatism, and LASIK for residual hyperopia, hyperopic astigmatism or mixed astigmatism on his own pa- tients, but added that he has started performing laser astigmatic incisions on either the IFS (Abbott Medical Optics, Santa Ana, Calif.) or the LenSx (Alcon, Fort Worth, Texas) for mixed astigmatism. For Richard S. Hoffman, MD, clinical associate professor of oph- thalmology, Casey Eye Institute, Oregon Health & Science University, and in private practice at Drs. Fine, Hoffman & Sims, Eugene, Ore., there is no question about which procedure that he prefers and recommends for novices. "PRK for residual myopia," he said, especially in premium patients, as they are already unhappy they did not have "perfect" vision and "want it fixed quickly." He does recommend waiting until the initial cataract wound is secure, about 3 months, before performing any LASIK enhancement surgery. "By about 2 weeks or so, the re- fraction will be stable, but the longer you can wait before resolving the residual errors, the better for the wound," he said. Additionally, heal- ing time is much shorter for LASIK than PRK, and these are already dissatisfied patients. Intentionally adding a longer healing time may not make sense in every case and LASIK may be a better choice, he said. Conversely, a general ophthal- mologist or cataract surgeon with- out refractive training or a great deal of refractive surgical experience might be better served by perform- 30-37 Feature_EW July 2014-dl_Layout 1 6/30/14 8:42 AM Page 33

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