Eyeworld

and it is important for ophthalmolo- gists to diagnose and properly treat. I believe we need to do a better job of screening and diagnosing. Advanced tear film diagnostics can assist the cataract surgeon by aiding in quicker and more accurate diag- nosis of dry eye for improved accu- racy in IOL power calculation and surgical planning, as well as maxi- mizing postoperative acuity and satisfaction. As we move to this aging population, we're going to be overwhelmed with patients. I think we need to be more efficient in evaluating and treating dry eye. Dr. Holland is professor of clinical ophthalmol- ogy at the University of Cincinnati. He can be contacted at eholland@holprovision.com. T he understanding of dry eye disease has evolved with time, but it is still underdiagnosed. Studies on prevalence of dry eye indicate that it could range any- where from 7% to 48%, which also depends on how dry eye and ocular surface disease are defined. We do know that dry eye is increasing with age, and as patients live longer, we're going to have more patients with dry eye to treat. A decade ago, clinicians consid- ered the majority of dry eye to be aqueous tear deficiency, but the most common cause of dry eye is meibomian gland dysfunction (MGD) with evaporative dry eye. The second most common is the because it can affect the accuracy of measurements used for determining candidacy and for IOL selection and power. Potential consequences of its effects include excluding a patient from consideration for a multifocal IOL due to irregular astigmatism, selecting the wrong monofocal IOL, selecting the wrong IOL power, planning for toric IOLs or LRIs when not needed, positioning a toric IOL on the wrong axis, and performing unnecessary lens exchanges or enhancements. Dry eye is very common in both the refractive and cataract patient population and has a significant im- pact on a patient's vision, comfort, and quality of life. It can have signif- icant impact on surgical outcomes, by Edward J. Holland, MD The impact of ocular surface disease on refractive cataract surgery Edward J. Holland, MD, has received a retainer, ad hoc fees, or other consulting income from: Abbott Medical Optics, Alcon Laboratories Inc., Bausch & Lomb, SARCode BioScience, Senju Pharmaceuticals, TearScience, and WaveTec Vision Systems. He is a member of the speakers bureau of Abbott, Alcon, and Bausch & Lomb. Dr. Holland has received research funding from Alcon and WaveTec. The MMP-9 inflammatory marker is another in-office tear analysis, which tests for the presence of the matrix metalloproteinase MMP-9 by giving a positive or nega- tive test result in 10 minutes. This test indicates whether there is an inflammatory component to the dry eye disease and hence can guide which patients should be treated with anti-inflammatory therapies. Serum testing for biomarkers of Sjogren's syndrome can be helpful for these types of patients as well. Standard biomarkers have a speci- ficity of 40% to 60% and are not de- tected in early stages of the disease. A lot of diagnostic modali- ties enable you to evalu- ate dry eye disease on a more specific level. Some of the advanced diagnostic modalities include tear composition analysis, serum biomarker testing, tear film structure and other image analysis. Tests include osmolarity, the MMP-9 inflammatory marker, serum testing for biomarkers of Sjogren's syndrome, and lipid layer analysis. Tear film osmolarity has been embraced by a number of advocates with its potential for in-office tear analysis. A CLIA waiver is needed, but it is a small, portable, and user- friendly device that is easily placed in the examination lane or testing suite. The device takes a very small sample of tear (i.e., 50 nL) from the lateral tear meniscus without the need for any topical anesthetic. After 10 seconds, the device produces an osmolarity number for each eye that confirms the diagnosis and severity of dry eye disease. While it does not specify the type of dry eye disease (i.e., aqueous-deficient, evaporative, combination), it can be helpful in gauging patient response to dry eye treatment. by Terry Kim, MD Using diagnostics to drive treatment of dry eye disease Terry Kim, MD, has received a retainer, ad hoc fees, or other consulting income from: Alcon Laboratories Inc., Bausch & Lomb, Ivantis, Kala Pharmaceuticals, Ocular Systems Inc., Ocular Therapeutix, Omeros Corporation, PowerVision Inc., Shire, and TearScience. mixed pattern with evaporative and aqueous tear deficiency. Of the patients with a classified dry eye disease subtype, 86% demonstrated signs of MGD. This is the leading cause of dry eye throughout the world, and can be influenced by age, hormonal disturbance, and topical medication. Additionally, insuffi- cient lipids in MGD can create hyperosmolarity and tear film instability and can lead to evapora- tive dry eye and ocular surface inflammation. About 40% of MGD patients come into the office complaining of classic dry eye symptoms. Note that 16% of patients with MGD come in as surgical patients, and it's impor- tant to diagnose these patients and treat them. There are an estimated 55 mil- lion Americans with dry eye disease and an estimated 39 million with undiagnosed dry eye. This number is going up every year because of the aging population. There have been a number of advancements in cataract and refractive surgery, but these can be neutralized by dry eye disease and poor ocular surface quality. The tear film is the first refractive interface, and the anterior surface of the precorneal tear film has the greatest optical power of any ocular surface. Dry eye disease can have an im- pact on refractive cataract outcomes To claim CME credit, turn to back page. A large number of Americans suffer from dry eye. EW Ocular care Supplement July 2014-DL2_Layout 1 6/30/14 8:59 AM Page 52

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