Eyeworld

EW CORNEA 60 February 2016 by Michelle Dalton EyeWorld Contributing Writer Dr. de Luise said. And because of that, the diagnostics currently avail- able "have not been fairly evaluated objectively to see which one truly is beneficial enough to the generalist to say that this should be your go-to test," Dr. Latkany said. "This disease entity is so com- plex that you never say never, but I highly doubt there will be one single test any time soon that will distin- guish between the types of dry eye." Expert opinions Ocular surface specialists may not need tests to diagnose dry eye, Dr. Latkany said—they just need to use the HOSE approach. "Get a good History while Observing the patient, and follow this with a detailed Slit lamp Exam," he said. The more clinicians take in- terest in seeing patients with dry eye complaints, the more they will be able to rely on the HOSE approach in diagnosing and managing dry eye patients. "Just by looking you can tell the patients who have allergies, or The latest dry eye diagnostics give clinicians more information about a patient's condition, but no one test alone can provide all the answers M ention dry eye disease to most ophthalmol- ogists, and you'll hear about the difficulty in diagnosis, treatment, and patient frustration. Even among experts, debate remains about how to best qualify and quantify the disorder, and whether or not the dis- ease is dry eye or a tear dysfunction. "There are many people who have plenty of tears, but they're unstable or they're not the right kind of tears. We're not at a point where we can identify all the dif- ferent types of tear disorders," said Stephen Pflugfelder, MD, professor of ophthalmology, Baylor College of Medicine, Houston. Typically, dry eye is loosely cate- gorized as either evaporative dry eye (EDE) or aqueous deficient dry eye (ADDE), but there are multiple other etiologies that produce dry eye-like symptoms, such as conjunctival chalasis or superior limbic kerato- conjunctivitis, Dr. Pflugfelder said. "Ophthalmologists are seeking quantitative testing for dry eyes," said Vincent P. de Luise, MD, assistant clinical professor of oph- thalmology, Yale University School of Medicine, New Haven, Conn. "People like knowing their num- bers, for example, blood pressure and glucose. That's how the world of systemic medicine functions. We are getting closer in ophthalmology with diagnostic testing, but we don't currently have a quantitative value accepted by all for dry eye." Dr. de Luise thinks that the disease will remain "largely a clinical diagnosis" made at the slit lamp, coupled with "astute clinical listen- ing" of the patient complaints, a feeling echoed by Robert Latkany, MD, director, Physician Eyecare of NY, New York, who thinks a clinical exam is more useful than any cur- rently marketed diagnostic tool. Dry eye "is a very heterogeneous group of distinct conditions that we lump into this term 'dry eye disease' or 'dysfunctional tear syndrome,'" Running around in circles continued on page 62 Device focus Exposure zone lissamine green staining of the conjunctiva in a patient with Sjogren's syndrome-associated dry eye Source: Stephen Pflugfelder, MD rosacea, or how effective their blink rate is and if it's often enough," Dr. Latkany said. But for the general ophthalmologist, "some of these tests could be of some value." He's particularly cautious about advocat- ing the use of any one test because he's not yet convinced of the accu- racy. "There's no 'pregnancy test' yet for dry eye," which would give a yes or no result, he said. "There has yet to be a multicenter unfunded study that evaluated these tests to confirm company findings. If you put 10 dry eye specialists in a room, they'd all have extremely different opinions on many points within dry eyes." Newer diagnostics In the past few years, several new di- agnostic tests have been introduced with the aim of clarifying whether or not there are indications of dry eye, but none can uniformly deter- mine if someone has EDE or ADDE. The Sjö test (Bausch + Lomb, Bridgewater, N.J.), for example, can help identify one of the many causes of dry eye, in this case, Sjögren's syndrome (SS). SS is typically diag- nosed when there are elevated levels of the disease specific serum auto- antibodies Ro and La; the Sjö test "combines traditional and novel, proprietary biomarkers to create an advanced diagnostic panel for the early detection of Sjögren's syn- drome." Other new-to-market diagnostic tests include the InflammaDry (Rapid Pathogen Screening, Sarasota, Fla.), the TearScan lactoferrin test (Advanced Tear Diagnostics, Birmingham, Ala.), TearLab's osmolarity test (San Diego), LipiView/LipiFlow (TearScience, Morrisville, N.C.), and lysozyme testing. These are in addi- tion to the bevy of tests clinicians already use, including tear break-up time, fluorescein staining, lissamine green staining, and Schirmer's test. "These newer tests offer a way of making the diagnosis a bit more mathematical or numerical, and

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