OCT 2013

EyeWorld is the official news magazine of the American Society of Cataract & Refractive Surgery.

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October 2013 Combined glaucoma and February 2011 cataract surgery EW FEATURE 77 Triple procedure showing promise for glaucoma treatment by Michelle Dalton EyeWorld Contributing Writer Combining phaco with two different glaucoma procedures may help further lower IOP and decrease medication use C all it what you will—ICE (for iStent, cataract, and ECP) or PIE (for phacoemulsification, iStent, and ECP), or some other acronym—but a triple procedure involving phaco, iStent (Glaukos, Laguna Hills, Calif.), and endoscopic cyclophotocoagulation (ECP, Endo Optiks, Little Silver, N.J.) is producing good outcomes and has the potential to reduce medication use in mild to moderate glaucoma patients, experts say. Many glaucoma surgeons were already combining ECP and phaco, as the dual procedure reduces intraocular pressure (IOP) more than cataract surgery alone. Likewise, the iStent has been used in combination therapy for the same purposes. Combining the three just makes sense, said Nathan M. Radcliffe, MD, assistant professor of ophthalmology, Weill Cornell Medical College, New York, who does caution the combined procedure is not appropriate for those patients who need a trab. Both ECP and iStent lower IOP better than cataract surgery alone, said Hylton R. Mayer, MD, Eye Doctors of Washington (locations in Chevy Chase, Md., Vienna, Va., and Washington, D.C.). "ECP's impact on aqueous production and iStent's role in aqueous outflow present complimentary mechanisms to lower IOP," he said. "While phaco/ECP or phaco/iStent have been shown to be effective at lowering IOP beyond cataract surgery, the typical impact on IOP lowering is not as good as with more invasive surgeries that may have traditionally been combined with cataract surgery, such as phaco/trabeculectomy or phaco/tube. It is expected that this triple procedure will provide an even greater IOP lowering effect than either phaco/iStent or phaco/ECP alone. More importantly, the risk profile of both ECP and iStent are far superior to the traditional glaucoma surgeries, trabeculectomy and tubes." The data on the phaco/iStent or phaco/ECP alone procedures is 'good,' but I'd love to see 'great' with the ICE triple procedure," said Parag Parekh, MD, in private practice, Laurel Eye Clinic, Brookville, Pa. Because tubes and trab "are surgeries with such bad complication profiles and side effect profiles, if there was a less invasive way to get pressures down, we should be doing it. A substantial pressure drop would be such a victory for patients, doctors, everyone." One concern for Steven R. Sarkisian Jr., MD, glaucoma fellowship director, Dean McGee Eye Institute, and clinical associate professor, University of Oklahoma, Oklahoma City, is that when he performs phaco/ECP, he "hits [patients] pretty hard with steroids to minimize the inflammation. Because I'm worried about a steroid response with the iStent, I only use loteprednol." With the triple procedure, Dr. Sarkisian uses high doses of difluprednate for six weeks and has noted that he hasn't seen any patient with a steroid response to date. "Glaucoma progresses and chasing it is no fun," Dr. Radcliffe said. "This is a way to buy yourself some time, buy the patient a bit lower pressure for some time. Those are huge advantages." Patient characteristics Dr. Radcliffe recommends the triple procedure in patients with higher baseline pressures or more borderline pressures. "This is a heavier version of microinvasive glaucoma surgery (MIGS), but cataract surgery alone is acceptable if the patient is well controlled on drops," he said. Angle anatomy is likely the decisive factor in making a good or poor candidate, Dr. Parekh said. For patients with mild or moderate glaucoma and cataract, he'll try the triple procedure first. "If it works, we're heroes," he said. "We've saved the patient from a procedure with huge adverse events. But trabs and tubes are still options if ICE doesn't work; you've lost nothing." He said the "best" candidate would be someone with a significant cataract and ocular hypertension "or very mild glaucoma and controlled on one medication," he said. "Maybe we can get them low enough to be off meds completely." Some of his first ICE patients have seen more than 10 mm Hg drops in pressure, he said. Dr. Mayer eliminates candidates if any one arm of the surgery would be contraindicated. "For ECP, that would be a history of or high risk for inflammation or cystoid macular edema; for iStent, inability to visualize angle structures, either due to corneal opacities or angle abnormalities. In addition, traditional glaucoma surgeries may be more appropriate for patients with advanced glaucoma and field damage or for whom target IOPs are very low (under episcleral venous pressures)," he said. The triple procedure "takes the MIGS approach for people with mild glaucoma and shifts the paradigm to more serious glaucoma cases," Dr. Sarkisian said. "Theoretically, I should get even lower pressures with this procedure than with dual iStent implantations." He added doing just two of the three procedures would reduce pressures, but might not be sufficient enough to get the patient off medications entirely. (Although if the iStent is placed directly over the collector channel, it will produce a more substantial drop in IOP than if it's placed elsewhere, he said.) Learning curves As with any new procedure, learning curves are to be expected, but the triple procedure has an almost nonexistent one unless the surgeon has never performed an ECP or implanted the iStent. Everyone agreed, however, that the phaco portion of the surgery has to be done first, as it's the most invasive. Drs. Sarkisian and Parekh perform phaco first, then the ECP, then the iStent. Dr. Sarkisian uses DuoVisc (Alcon, Fort Worth, Texas) during cataract surgery, removes the viscoelastic after cataract surgery, fills up the sulcus with Healon GV (Abbott Medical Optics, Santa Ana, Calif.) before performing the ECP portion, and removes the Healon GV. He then uses Miochol (acetylcholine chloride, Novartis, Basel, Switzerland) to rapidly bring dilation down, finally using more Healon GV in the anterior chamber and on the corneal surface before inserting the iStent. Dr. Parekh performs the ECP as the second step "because you're already in position. The microscope is AT A GLANCE • Combining phacoemulsification, ECP, and iStent may produce lower pressures and reduce medication dependence. • Complete OVD removal is critical in the triple procedure. • Candidate choice is crucial— patients with mild to moderate glaucoma may be best suited for the procedure. in the right spot, the patient's head is in the correct position, and that makes it more efficient and easier," he said. "Furthermore, I think I'd feel a bit nervous manipulating the eye too much after the iStent is placed," which is why he prefers the ECP as the second step and not the last. Dr. Mayer thinks ECP is easier to perform but qualifies the iStent as less invasive (albeit more challenging), leaving the order of surgery up to the individual surgeon and his/her comfort level. Dr. Radcliffe said surgical details may sway a surgeon toward one order over the other, but he only removes the OVD after the ECP portion of the surgery, and doesn't really have a preference. He does, however, use the endoscope to place the iStent rather than a gonioscope. "Sometimes that works, sometimes I do have to go back and use a gonio," he said. "The issue with an endoscope is that it's a little tight, and a little more difficult to manipulate." To date, Dr. Radcliffe has performed about 30 of the combined procedures, and none of his patients has developed any complications. "It's fun to do—you're doing new things and looking at the eye in new ways. We need a formal analysis of the data, but so far I've been impressed," he said. "We're decreasing the patient's probability of needing future surgical interventions. I'm looking at these cataract patients and thinking these very safe procedures may be able to push off a trab another five years. I'm so hopeful for this approach, and I do think ultimately this is how we will be managing patients in the future." continued on page 78

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