Eyeworld

3 Supported by Alcon Laboratories Inc., Allergan Inc., Shire Pharmaceuticals, TearLab, and TearScience 4. Albietz JM, et al. Chronic dry eye and regression after laser in situ keratomile- usis for myopia. J Cataract Refract Surg. 2004;30:675–684. Dr. Schallhorn is professor of oph- thalmology, University of California, San Francisco; chief medical director, Optical Express, Glasgow, U.K.; and in private practice in San Diego. He can be contacted at scschallhorn@ yahoo.com. Cataract Patients' Ocular Surface (PHACO) Study. 2011 ASCRS•ASOA Symposium & Congress. 2. Epitropoulos AT, et al. Effect of tear osmolarity on repeatability of keratometry for cataract surgery planning. J Cataract Refract Surg. 2015;41:1672–1677. 3. Donnenfeld ED, et al. Measurement of refractive surgery induced dry eye using tear osmolarity testing. 2011 European Society of Cataract & Refractive Surgeons annual meeting. Examining impact In this monograph, noted experts will discuss the influence of OSD on cataract and refractive out- comes, the consequences of an unstable tear film, and strategies for diagnosing asymptomatic and symptomatic OSD. References 1. Trattler WB, et al. Cataract and dry eye: Prospective Health Assessment of differences in intraocular lens (IOL) power calculations. 2 Donnenfeld et al. reported that patients with tear hyperos- molarity that remained untreated before LASIK were more likely to have worse visual outcomes. 3 According to research by Albietz et al., patients with chronic dry eye who had LASIK were more likely to experience refractive regression. 4 continued from page 1 The negative staining is at least equally important as positive staining because it represents a mechanical cause of OSD, includ- ing anterior basement membrane dystrophy (ABMD) and nodular degeneration. These diseases not only skew keratometric values, but also lead to a very quick tear break-up time and exacerbate fluctuating vision (Figure 1). Symptomatic vs. asymptomatic Patients' symptoms may not correlate with staining. Young patients can have very mild stain- ing because they often produce reflex tears and compensate, but they may have disproportionately severe symptoms. In such cases, tear osmolarity and MMP-9 test- ing can help qualify the level of dry eye disease. Older patients can be asymp- tomatic for classic symptoms but have significant corneal staining. This may result from medications, chronic progressive dry eye, or different disease states. As we know, diabetes causes peripheral neuropathy, decreasing sensation. In my experience, older patients often display more of the classic symptoms when meibomian gland dysfunction represents a more significant com- ponent of their dry eye disease. Although vision fluctuation is the major complaint in older patients, those with MGD com- plain most often of redness and a burning sensation, particularly upon awakening. It is worse in the morning because over- night the lid margin remained along the ocular surface without blinking away inflammatory mediators. This is also different from the sharp pains of recurrent corneal erosion syndrome (RCES) that are part of the differential diagnosis of ocular discomfort that is worse in the morning, but I do see that posterior blepharitis patients have greater anterior basement membrane dystrophy and RCES. Therefore, older patients with a predominant MGD com- ponent to their mixed dry eye disease will have more symptoms. Surgical planning for advanced technologies If patients have corneal stain- ing and plan to have advanced technology IOL implantation or femtosecond laser-assisted cat- aract surgery, I prescribe topical steroids fairly early in the process and an anti-inflammatory, such as cyclosporine, particularly for long-term treatment of dry eye. I ask them to return in three to four weeks to repeat preoperative measurements. I also offer a pack- age with an additional discount on LipiFlow thermal pulsation because, in my experience, dry eye can worsen in about one in three patients after surgery. Conclusion Many patients with OSD have marginally compensated eyes. They may be able to tolerate it, with few symptoms, but surgery may exacerbate OSD and symp- toms. Therefore, we need to take a number of steps to identify OSD and manage it preoperatively, which will help us improve results and improve patient satisfaction. References 1. Trattler WB, et al. Cataract and dry eye: Prospective Health Assessment of Cataract Patients' Ocular Surface (PHACO) Study. 2011 ASCRS•ASOA Symposium & Congress. 2. Epitropoulos AT, et al. Effect of tear osmolarity on repeatability of keratometry for cataract surgery planning. J Cataract Refract Surg. 2015;41:1672–1677. 3. Sambursky R, et al. Prospective, multicenter, clinical evaluation of point- of-care matrix metalloproteinase-9 test for confirming dry eye disease. Cornea. 2014;33:812–818. Dr. Yeu is assistant professor, East- ern Virginia Medical School, and in private practice, Virginia Eye Con- sultants, Norfolk, Virginia. She can be contacted at eyeu@vec2020.com. Figure 1. Slit lamp image of central ABMD. The fluorescein dye demonstrates negative staining centrally over the ABMD.

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