Eyeworld Daily News

EW SHOW DAILY 68 P atients come to the clinic for many different rea- sons, often with several issues at once; at least one of them will almost cer- tainly be some form of ocular surface disease (OSD), said Eric D. Donnenfeld, MD, New York, speak- ing at an EyeWorld CME Education symposium on advanced tear film testing that aimed to "revolutionize the way clinicians think" about di- agnosing and treating the condition. An audience survey at the start of the session revealed that 47% of attendees had "high confidence" in current testing and treatment proto- cols for OSD. Christopher E. Starr, MD, New York, however, begged to differ, challenging attendees with the statement that "accurately diag- nosing OSD is not as easy as we used to think." For one thing, said Dr. Starr, the various conditions affecting the ocu- lar surface, including the different kinds of dry eye, conjunctivitis, and related conditions such as blephari- tis, preservative toxicity and base- ment membrane dystrophy, tend to coexist and have considerable over- lap in signs and symptoms, blurring the issue significantly. For another, he said, the tech- niques clinicians traditionally rely on to diagnose OSD are "very largely subjective, highly variable, very often unreliable and not repro- ducible." In this regard, the positive predictive values (PPVs) of these tests—the proportion of positive results that are true positives—are revealing: Schirmer's test (in which 48% of attendees expressed "high confidence") has a low PPV at 31%, tear breakup time at 25%, corneal and conjunctival staining at 31%, and tear meniscus height at 33%— "all pretty low when it comes to pos- itive predictive value," said Dr. Starr. In contrast, measuring tear os- molarity—which has been around for a while but "largely outside the hands of the average practitioner"— has a PPV of 87%. Dr. Starr proposed that measur- ing tear osmolarity should be the gold standard for diagnosis, a posi- tion that he said is supported by the 2013 AAO Preferred Practice Pat- terns. In addition, the 2007 Dry Eye Workshop (DEWS) redefined dry eye to include hyperosmolarity as one of the key pathophysiologic features of the condition, and various studies demonstrate a linear relationship between osmolarity and dry eye severity. Assessing 'complex chemistry' The tear film is, as is now well- known, a "complex mixture of pro- teins, mucins, oils, and electrolytes," in which the lipid layer is as impor- tant as the aqueous component, said Edward J. Holland, MD, Cincin- nati. This complex chemistry, he said, can now be assessed to provide new information for managing OSD. A quick and easy starting point that the average practitioner tends to overlook is expressing meibomian gland secretion. While there are more specific and accurate ways of assessing meibomian gland func- tion, Dr. Holland said that it's a good place to start given that 86% of patients with classified dry eye dis- ease had some form of meibomian gland dysfunction. Other aspects of the tear film chemistry that can now be assessed include lactoferrin and matrix met- alloproteinase 9 (MMP-9)—the latter expressed by distressed epithelium, providing quick diagnostic evalua- tion. In addition to its chemistry, tear film structure can now also be assessed to provide valuable infor- mation for the diagnosis and man- agement of OSD, said Marguerite B. McDonald, MD, New York. The lipid layer, for instance, can now be assessed using white light interfer- ometry. Powerful new tools including the Keratograph 5M (Oculus, Arling- ton, Wash.) and ubiquitous ocular coherence tomography (OCT) machines can also be used to assess tear film structure. All these techniques and tech- nologies for assessing the tear film, said Dr. Donnenfeld summing up, can be used to make the manage- ment of OSD truly evidence-based, thus improving diagnosis and treat- ment. At the start of the session, an audience survey revealed that only 30% of attendees believed that diag- nostic tests for OSD should be per- formed at the initial point of care; at the end of the session, the percent- age had risen to 73%. EW Editors' note: This event was supported by unrestricted educational grants from Nicox (Valbonne, France), PRN (Plymouth Meeting, Pa.), TearLab (San Diego), and TearScience (Morrisville, N.C.). Saturday, April 20, 2013 EyeWorld Education Diagnosing OSD 'not easy' by Chiles Aedam R. Samaniego EyeWorld AP Senior Staff Writer or somewhat routinely, 18% only use both rarely. A significant portion of the symposium will discuss this issue with dosing and review the pros and cons of doing this in a majority of patients. Below are some other key pearls and discussion topics that will be covered by the expert panel. • Review the latest available anti-in- flammatory therapies; • Discuss means of how to decrease or eliminate inflammation for refractive cataract patients; • Learn why outcomes of multifocal IOLs will be compromised if in- flammation is present and how to prevent this; • Review the importance of using OCT for preop evaluation of refractive cataract patients; • Hear how to identify potential steroid responder patients prior to surgery and treat their inflamma- tion; • Understand the factors that influ- ence inflammation; • Hear panel recommendations for the most appropriate pre- and postop inflammation treatment regimen; • Review the treatment options for a diabetic patient with CME; • Learn how an anti-inflammatory's formulation can affect the efficacy of the drug; • Discuss how a drug's inactive in- gredients can impact drug trans- mission through the tissues; and • Review the similarities and differ- ences between the available brand-name and generic pharma- ceutical options. This CME symposium will take place in the Intercontinental Hotel, Grand Ballroom tonight, with a 5:00 p.m. registration and reception, and a 5:30 p.m. start time for the one- hour symposium. This program is supported by an unrestricted grant from Bausch + Lomb (Rochester, N.Y.). Onsite registration space is available. EW continued from page 67

• Cover