discovering dry eye
Do Your Patients Have Contact Lens-Related Dry Eye? Ask Them
BY JASON J. NICHOLS, OD, MS, AND KELLY K. NICHOLS, OD, MPH, PHD
Symptom assessments and patient history are key to diagnosing dry eye, as many believe that dry eye syndrome is a symptom-based disease. Several recent prevalence studies have used a symptom-based diagnostic definition of dry eye syndrome. Ocular symptoms associated with dry eye syndrome include ocular fatigue, discomfort, redness, itching, dryness, irritation, crusting of lids, scratchiness, epiphora, discharge, blurry vision, pain, photophobia, blinking abnormalities and foreign body sensation.
Contact Lens-related Dye Eye
Recent studies have suggested that the two primary symptoms associated with contact lens-related dry eye are dryness and discomfort. Studies have shown that a major factor of clinician diagnosis of contact lens-related dry eye is patient self-perception of dry eye during contact lens wear. ("My eyes feel dry when I wear my contact lenses, Doc.") Other studies have indicated that contact lens-related dry eye symptoms may also have a diurnal cycle, with a greater frequency and/or intensity in the evening after a full day of lens wear.
Clinicians should utilize these symptom evaluations to better manage patients via different lens materials or designs. At least two contact lens companies have developed lens materials for contact lens-related dry eye patients, including Extreme H2O's hioxifilcon A (Hydrogel Vision Corp.) and Proclear's omafilcon A (CooperVision, formerly Biocompatibles) and they should be applauded for their efforts. Both of these materials are dehydration-resistant, and clinical studies of lens dehydration with both materials are promising. Additionally, studies have shown that CIBA Vision's Focus Night & Day lens is associated with less dryness than Vistakon's Acuvue lens for patients who discontinue overnight lens wear.
Assess Symptoms, Keep Patients
Dry eye symptoms during contact lens wear could lead to reduced wearing time or discontinuation of lens wear. One study found that after 5 years of lens wear, approximately 12 percent of contact lens patients permanently discontinued contact lens wear primarily due to discomfort and dryness. In that study, 49 percent of patients who discontinued lens wear were refitted at least once due to the discomfort, and all had reduced their lens wearing times prior to discontinuation. Still another survey showed that 18 to 30 percent of soft lens patients had dry eye symptoms, 12 to 21 percent were symptomatic enough to reduce their wearing time and 6 to 9 percent could not wear contact lenses due to dryness symptoms. In short, you must assess dryness and discomfort to maintain successful and happy contact lens patients.
The epidemiology of contact lens-related dry eye is still not well understood, although studies indicate that as many as 50 percent of the 35 million contact lens wearers in the United States have dry eye symptoms. If we expand the definition of contact lens-related dry eye to include a sign and symptom, then almost nine million lens wearers could suffer from contact lens-related dry eye.
With the number of contact lens wearers continuing to grow, it is likely that the prevalence of lens-related dry eye will increase, as no significant advances have been made to reduce the dry eye problem in lens wearers. Contact lens-related dry eye is arguably one of the biggest challenges facing the contact lens industry. However, the contact lens practitioner has the skills to more effectively manage these patients, if they just simply ask.
Dr. Jason Nichols is a senior research associate at the Ohio State University College of Optometry. Dr. Kelly Nichols is assistant professor of clinical optometry at The Ohio State University College of Optometry in the area of dry eye research.