My October column looked at issues that arise when individuals who have dry eye disease (DED) present for contact lens evaluation. The temptation may be to proceed, hoping that patients will “adapt” or “get better.” A more realistic and perhaps benevolent approach is to first evaluate a patient, diagnose and treat the primary underlying pathology, and then move on to placing lenses on the patient’s eyes.
Assessment should address the primary underlying cause, i.e., is there a deficiency of the lipid layer, the aqueous layer, or both? Relying on symptoms alone will likely lead to under diagnosis, especially for milder disease (Bron et al, 2014).
Khanal et al (2008) reported that tear osmolarity is the best single test for diagnosing dry eye. Other studies agree (Bron et al, 2014; Baudouin et al, 2013; García-Resúa et al, 2014). Careful evaluation of the lids—especially meibomian gland function and structure, meibum quality and quantity, lid telangiectasia, and orifice obstruction—is useful in differentiating the underlying pathology. Ocular surface staining with vital dyes, commonly used to evaluate for dry eye, actually measures the extent of ocular surface damage rather than dry eye severity (Khanal et al, 2008). Clinical surveys provide insight into the severity of symptoms; for example, the McMonnies Dry Eye Questionnaire is both sensitive (98%) and specific (97%) in identifying dry eye.
Once you establish a definitive cause or causes, the next step is patient education, which is always vital when managing any chronic, complex disease. Dry eye is, to a great extent, self treated. Patients must do much of the therapy at home, typically over a period of weeks or months; this requires education specific to those tasks.
Education can have a significant impact on outcomes. Rosdahl et al (2014) conducted a voluntary survey of ophthalmology patients regarding education preference; the preferred method of communication was one-on-one with the eyecare provider (55%), followed by recommended websites (38%), and printed materials (36%). Don’t consider anything too basic for patient instruction; Feng et al (2016) reported a two-fold increase in eye drop instillation after in-office training.
Any long-term condition that affects quality of life and requires ongoing therapy can be discouraging. Dry eye patients need to understand why contact lens wear has been delayed, the expected benefits of treatment, and the anticipated duration of the therapy. Knowing that there is a “light at the end of the tunnel” is encouraging to individuals who are delaying contact lens wear to optimize the ocular surface for eventual contact lens wear.
Compromised ocular surface health is a barrier to successful contact lens wear. In dissatisfied wearers, “dryness” represented 76% of all ocular symptoms reported, and “discomfort” accounted for 67% of all ocular symptoms reported (Richdale et al, 2007). Proactively treating DED prior to lens wear can avoid many of these issues. CLS
For references, please visit www.clspectrum.com/references and click on document #254.
Dr. Townsend practices in Canyon, TX, and is an adjunct professor at the University of Houston College of Optometry. He is treasurer of the Ocular Surface Society of Optometry and conducts research in ocular surface disease, lens care solutions, and medications. He is also a consultant or speaker for Alcon, Allergan, NovaBay, Shire, TearLab, and Science Based Health. Contact him at firstname.lastname@example.org.