Contact Lens Practice Pearls
‘Tis the Season for Dry Eye
BY GREGORY J. NIXON, OD, FAAO
Living in the Midwest, I often characterize the time from first bloom to first frost as ocular allergy season and the time from first frost to first bloom as dry eye season. During the winter we experience substantial changes in relative humidity that can adversely impact evaporative dry eye, lens hydration, and reflex tearing. These effects of the ambient environment can exacerbate symptoms of chronic dry eye, or they can be the additional factors that cause borderline dry eye patients to experience symptoms only during the winter. In addition to maximizing contact lens performance with standard dry eye treatment and proper lens and care system selection, there are other strategies that can help alleviate environmentally induced ocular discomfort until springtime rolls around again.
Recreate Your Environment
Seasonal changes in climate impact more than the humidity outdoors. Indoor humidity levels also decrease in winter months due to indoor heating systems circulating warmer and dryer air into our homes and workplaces. I have found a tremendous benefit in using room humidifiers to reestablish moisture in the air. Placing a humidifier in the main room or office in which a patient spends a significant amount of time at work can help to reduce tear evaporation, especially during long periods of reading or computer work. Moreover, the best benefit of humidifiers is often overnight use in a bedroom. Patients who have lagophthalmos can particularly benefit from the increased moisture while they sleep to prevent exposure keratitis. I also recommend that those patients instill an over-the-counter (OTC) lubricant gel or ointment at bedtime to maintain ocular surface integrity during sleep. Undoubtedly, it is best to avoid starting the day by applying a contact lens on an already compromised eye.
Another challenging winter environment is the car. The proximity of heat vents blowing dryer air can significantly impact contact lens wettability. Further, if there is already damage to epithelial cellular integrity, the flow of air to the compromised ocular surface can invoke reflex tearing. Both of these scenarios not only affect ocular comfort, but could impair vision and ultimately impact driver safety. Therefore, it is best to warm up your car before you leave so that the heat flow can be minimized while driving. Further, it is sometimes beneficial for contact lens wearers to wear their glasses while commuting. Spectacles can shield the eyes and help protect the ocular surface to maximize healthy contact lens wear at work.
Enhance Lens Wearing Comfort
As outlined in my May 2012 column, there are OTC agents that are safe and effective for use while wearing contact lenses. They can sustain lens hydration and lubricate the ocular surface to aid comfort. It is best to regularly instill these agents throughout the day to prevent symptoms before they happen.When daytime symptoms still develop, a brief 20-minute midday removal of lenses to independently lubricate them and the ocular surface can facilitate improved on-eye lens performance throughout the remainder of the day.
While dry eye and contact lens discomfort are often the most frequent patient-reported symptoms that we encounter, some patients suffer in silence. More insightful questioning may bring to light issues with decreased comfortable wear time or limited wear time. So, be sure to actively investigate dry eye symptoms and to educate patients on the challenges of a dry environment during the winter months. Advise them to employ some of the strategies mentioned above to support comfortable lens wear year round. CLS
Dr. Nixon is a professor of clinical optometry and director of extern programs at The Ohio University College of Optometry. He is also in a group private practice in Westerville, Ohio. He is on the Allergan Academic Advisory Board, the B+L Advisory Board, the Alcon Glaucoma Advisory Board, and the Alcon Speakers Bureau. You can reach him at firstname.lastname@example.org.