This article is more than 5 years old. Information may no longer be current.
Consider nighttime evaporative stress in all dry eye patients
Click Here to Manage Email Alerts
Research published over the last decade strongly reinforces the idea that dry eye specialists should be aggressively looking for – and subsequently managing – nocturnal evaporative stress in the dry eye and meibomian gland dysfunction patient populations.
The term nocturnal evaporative stress (NES) describes any situation where a patient suffers desiccating stress at night. Dry eye patients suffering from NES often complain that their symptoms feel worse in the morning.
Traditionally, we have advised patients to stay away from overhead fans, air vents and other physical sources that may disrupt the tear film. However, dry eye researchers and clinicians are becoming increasingly aware that NES has several dynamic, often overlapping, causes, such as incomplete eyelid seal, nocturnal lagophthalmos, sleep apnea, floppy eyelid syndrome and aqueous deficient dry eye (Korb, Blackie, Nau and Liu et al.). As we continue to refine our dry eye patient intake process, we should do a little more investigating to discover how the patient is faring at night. Lid seal is a good place to start.
Research on lid seal
Korb, Blackie and Nau recently studied and reported on the aggravating role of incomplete eyelid seal. Their research assessed patients’ lid seal efficacy and compared the severity of signs and reported symptoms. This study provides excellent insight into the prevalence of incomplete lid seal, as well as the role it plays in both NES and dry eye manifestation in general.
The study revealed that incomplete lid seal correlates neatly with the presence of moderate-to-severe dry eye signs and symptoms, that “moderate” incomplete lid seal was common in the general patient population, and that lid seal problems were extremely common in patients older than 50 years, with 50% of patients 61 to 80 years old showing signs of poor seal. This study reinforces the belief that every dry eye patient should be evaluated for incomplete lid seal, especially those with morning dry eye symptoms and those with identified MGD, which greatly exacerbates the problem.
Measuring lid seal
Lid seal performance was measured via the Korb-Blackie lid light test, which uses a transilluminator to measure light leakage through the conjunctival papillae. I use this test in my practice to quickly assess lid performance, as the test itself takes very little time and can be done in any exam room.
In a dark room, place a fully illuminated transilluminator gently against the closed relaxed upper eyelid at the superior junction of the tarsal plate. The amount of light escaping between the upper and lower lid margins indicates a lack of closure. I supplement this technique with sodium fluorescein corneal staining and lissamine green staining. If fluorescein staining is particularly strong in the inferior third of the cornea, the patient likely has an incomplete blink or other lid performance issue. Lissamine green staining on the conjunctiva is beneficial to identify early signs of dry eye.
Treatment options
Once I have identified a patient suffering from NES with poor lid seal performance, I talk them through treatment options based on their lifestyle and preferences. A common starting point is an OTC nighttime lubricant ointment, which is applied immediately before bedtime. It is worth noting that many patients dislike this option and find it inconvenient, as ointment can blur vision and be greasy, requiring additional work in the morning for removal.
Eyelid taping, wherein a seal is created by taping the upper eyelid to the skin under the eye, is another option. However, some patients are intolerant to adhesives, and others do not like their vision occluded at night nor in the morning upon wakening.
Given the challenges associated with ointments and taping, I recommend that my patients invest in a high-quality sleep mask to seal in moisture, improve eye lubrication and protect the eyes. A mask can also prevent air – such as leaking air from a CPAP mask – to reach the eye and create desiccating stress.
There are several options available on the market; Tranquileyes moisture goggles (Eye Eco) have worked well for my patients. (See accompanying list for additional options.) The goggles, which are made from medical grade silicone and plastic, shelter the eyes completely from environmental stressors. They also come with removable foam inserts, which can be soaked in hot water prior to sleep to create additional moisture within the seal. This has proved immensely valuable for my MGD patients, especially those who have begun restoring healthy meibomian function with supplemental management options.
Investigate NES
Investigating and managing NES has helped reduce symptom severity and improve comfort for a large swathe of my dry eye patient population, including some of my most challenging patients. For instance, I recently had a 58-year old female patient present with dry eye and Sjögren’s syndrome, which is often associated with chronic, difficult-to-treat, moderate-to-severe symptoms. By identifying poor lid performance and recommending several management options, including a prescription eyedrop, artificial tears with increased viscosity, oral omega fatty acids, warm compresses and a moisture-buffering mask, I was able to reduce her symptom severity and restore comfort relatively quickly.
Searching for poor lid performance, investigating broader aggravating factors for NES and taking a more involved approach to management that blocks stressors and preserves environmental moisture are all effective, easy ways to make positive quality-of-life differences in our dry eye and MGD patients.
Moving forward, making NES a core part of patient intake and diagnostic work-up should not just be a best practice, it should be a necessity. – by Melissa Barnett, OD, FAAO, FSLS, FBCLA
References:
Korb D, Blackie C. Invest Ophthalmol Vis Sci. 2013;54(942).
Korb D, Blackie C, Nau A. Invest Ophthalmol Vis Sci. 2017;58(2696).
Liu D T-S, et. al. Invest Ophthalmol Vis Sci. 2005;doi:10.1167/iovs.04-0913.
For more information:
Melissa Barnett, OD, FAAO, FSLS, FBCLA, is a principal optometrist at the University of California, Davis Eye Center at UC Davis Health. She can be reached at drbarnett@ucdavis.edu.
Disclosures: Barnett reports relationships with ABB Optical, Acculens, Alcon, Alden Optical, Allergan, Anthem, Bausch + Lomb, Bruder, Contamac, CooperVision, Eye Eco, Gas Permeable Lens Institute, INC, Johnson & Johnson Vision, Ocusoft, Paragon Biotech, Scleral Lens Education Society, ScienceBased Health, Shire, STAPLE program, Synergeyes and Visioneering Technologies.