EyeWorld India June 2017 Issue

June 2017 56 EWAP cornea used; in the PHACO study, TBUT was abnormal in about two- thirds of patients scheduled for cataract surgery, said William Trattler, MD , Center for Excellence in Eyecare, Miami. Dr. Trattler was a lead investigator in the PHACO study, which was presented at several meetings but not yet published. Topography and keratometry are two revealing tests when evaluating the ocular surface. “You can see the quality of the topography is related to the quality of tear film and the ocular surface,” Dr. Trattler said. Although corneal staining has an important role in dry eye assessment, Dr. Holland shared this pearl: “Many times, you see charts where it says that corneal staining is a sign of moderate dry eye. If they put in fluorescein as the only stain and don’t see staining, they think the patient doesn’t have dry eye. I argue that corneal staining is a sign of severe dry eye. By the time there are multiple epithelial erosions, that patient has long- standing dry eye, not moderate dry eye,” he said. Don’t use staining as your main defining test for dry eye, Dr. Holland cautioned. When staining, Dr. Holland uses lissamine green, which can stain abnormal conjunctiva, whereas fluorescein only stains absent epithelium. A thorough slit lamp exam should be a regular part of the dry eye assessment as well. Dr. Holland checks the eyelids for lagophthalmos, examines the conjunctiva, and analyzes the lid margins. When pushing on the Meibomian glands, what comes out should be free-flowing, not opaque, paste-like, or hard to express, he said. “All of these things are done with a quick slit lamp exam,” he said. “Schirmer I testing can provide value, if performed correctly. A one-minute Schirmer I measurement multiplied by three provides a reasonable estimate of the five-minute result, and is much less irritating to the patient,” said Dr. de Luise. Another test he recommends is the Zone Quick Test, in which a thread impregnated with phenol red is placed in the outer lower conjunctival sac for 15 seconds, and the amount of tear wetting is measured. Explaining to patients If you find dry eye in patients, they may be surprised to hear that their cataract surgery can’t proceed right away. “I wish all patients would have good keratometry and topography readings out of the gate, but it’s frustrating because they often have dry eye, making these tests inaccurate,” Dr. Trattler said. The first thing Dr. Yeu does at this point is spend some time asking patients about symptoms such as intermittent blurred vision. She points out that intermittent blurred vision is a sign of dry eye, not their cataracts. Creating awareness of the problem helps to establish common ground, so patients recognize the importance of dry eye treatment, Dr. Yeu said. Dr. Hovanesian emphasizes to patients that dry eye is a chronic issue that will require their help to manage. “I tell the patient, ‘You have two diseases. We can fix the cataract, but we can’t cure the other. Dry eye is a lifelong issue and it will affect your vision even after cataract surgery.’ I also tell patients, ‘I can’t treat your dry eye, you have to treat it.’ They understand that they bear responsibility for success,” he said. Explaining the role that patients have in dry eye treatment helps boost compliance. Although every practice is a little different, the surgeons interviewed for this article generally still schedule surgery in patients with dry eye, but they may slightly alter the surgery schedule. This allows patients to use their treatments and then come in for a reevaluation. “They’re coming in expecting to have cataract surgery scheduled, and it’s disappointing to leave without a date,” Dr. Yeu said. “I generally have a 2- to 4-week turnaround time for surgery. If it’s mild to moderate, I’ll push those dates out 6 to 8 weeks. If they’re really unstable, maybe with a history of Bell’s palsy, exposure keratopathy, or other extraneous issues, then I’ll give dates that are 2 or 3 months out but have them come back in at 2 to 3 weeks to repeat measurements.” If a patient has only mild dry eye disease, without any corneal staining, and is receiving a monofocal IOL, Dr. Yeu may still go ahead and schedule surgery with a normal timeframe. Counseling the patient on their diagnosis, and the potential implications of worse dry eye in the post-operative period should be discussed with the patient. Such patients should be offered dry eye therapies pre-operatively, to be used indefinitely in some cases. Treatment for preop OSD Treatment for dry eye and OSD in patients scheduled for cataract surgery will vary depending on the type found. Many dry eye patients will have a Meibomian gland dysfunction (MGD) component, which is especially common in an aging population, Dr. Holland said. In these patients, he favors omega-3 therapy and is aggressive about recommending thermal pulsation therapy with LipiFlow (TearScience, Morrisville, North Carolina). “It heats the lids, pulsates the glands, and evacuates the old meibum. Lipiflow is the most effective therapy to relieve the MG obstruction and restore MG function. I don’t think anything else jumpstarts therapy as much,” Dr. Holland said. Depending on the patient, Dr. Holland may add oral doxycycline or consider topical azithromycin as well as a lipid-based tear. For MGD, Dr. Hovanesian recommends the use of warm compresses and Avenova (NovaBay Pharmaceuticals, Emeryville, California) or OcuSoft scrubs (OCuSOFT, Richmond, Texas). Patients with inflammatory dry eye often will need a short course of ocular steroids. Generic steroids can contain preservatives that are harsh, so Dr. Hovanesian favors Lotemax gel (loteprednol etabonate ophthalmic gel 0.5%, Bausch + Lomb, Bridgewater, New Jersey). “It’s very gentle on the surface, and there’s a low risk of pressure spikes,” he said. For aqueous-deficient dry eye, lifitegrast (Xiidria, Shire, Lexington, Massachusetts) or Restasis (cyclosporine ophthalmic emulsion 0.05%, Allergan, Dublin) are often used. “In the context of cataract surgery, lifitegrast may be better because it has a faster onset of action,” Dr. Hovanesian said. Dr. de Luise has found that cyclosporine works best in his aqueous-deficient patients. Primer – from page 55