ALTHOUGH IT is true that we should fit patients in the most comfortable and healthiest contact lenses available, switching patients to new contact lenses and contact lens solutions often is not the fix for potential contact lens dropouts.
Discomfort and dryness are the two most common reasons people stop wearing contact lenses, according to Eye & Contact Lens. We believe that the replacement contact lenses and solutions we suggest often are not effective at stopping these symptoms on their own. Specifically, the problem probably is not the lens or solution; more likely, the problem is the health of the ocular surface, and we need to address it.
MAKING MY POINT
Consider this: The average contact lens dropout rate is about 16%, according to an article in Review of Optometry. Patients drop out at all ages, but they are particularly likely to do so as they approach age 40, so that only about 30% of contact lens wearers are older than age 42, according to an article in Contact Lens Spectrum (a sister publication of Optometric Management.) Also, increasing with age is patients’ risk for dry eye disease (DED), which, in my, and others’ experiences, is often the underlying cause of contact lens intolerance, according to the same article.
Switching lens materials and solutions might buy contact lens wearers who have DED another few hours a day or a few years in their lenses, but, eventually, they will drop out as the disease continues to progress. In addition, these patients, who don’t know they have DED, may consider undergoing LASIK to achieve glasses-free vision, only to show up to discover from the LASIK surgery center, not you, their primary care eye doctor, that they have DED that prevents them from doing so.
WHAT WE CAN DO
If we test for DED in contact lens wearers of all ages, we can identify and treat it early and keep patients in contact lenses. This represents a major paradigm shift in our profession, from the idea that our contact lens wearers’ dryness and discomfort often is the result of using the wrong lenses or solutions, to the knowledge that these patients may have DED exacerbated by contact lens wear.
If we evaluate the health of the ocular surface in contact lens wearers of all ages during their annual evaluation, as we do in all non-contact lens-wearing patients, we can determine whether additional testing is warranted and, if so, identify and treat DED early and keep patients in contact lenses.
HOW TO DO IT
Consider purchasing objective point-of-care diagnostic tools, which can aid you in determining DED. These tools include:
- Fluorescein or lissamine green staining. Corneal or conjunctival erosions provide evidence the patient has DED.
- Meibomian gland expressor. The Korb Meibomian Gland Evaluator, from Johnson & Johnson Vision, enables you to evaluate the glands and their secretions. At my practice, we express the meibomian glands, evaluating both the number of functioning glands and the quality of the oils, which should be thin and clear but can become thick and whitish upon dysfunction.
- Meibography. This enables the assessment of the gland structure. LipiScan, from Johnson & Johnson Vision, and the Oculus Keratograph 5M offer meibography.
- Ocular surface interferometer. The LipiView II, from Johnson & Johnson Vision, provides a measurement of the tear film lipid layer’s thickness and reveals blink performance.
- Osmolarity testing. The TearLab Osmolarity System measures human tears’ osmolarity, or proportion of salt in the tears, to help you diagnose DED. Specifically, an osmolarity measurement greater than 300mOsml/L or a difference of 8mOsml/L between two eyes is indicative of DED, according to this test, which has an 87% predictive value for DED.
- MMP-9 inflammatory marker testing. The InflammaDry test, from Quidel, tells us whether MMP-9, an inflammatory marker, is present in the tears, indicating DED.
- Tear film scan software. The Oculus Keratograph (OCULUS Optikgerate GmbH) contains software that non-invasively measures tear quality and quantity.
- Lactoferrin/immunoglobulin E test. The TearScan MicroAssay System, from Advanced Tear Diagnostics, tests for lactoferrin, confirmatory for aqueous-deficient DED, and immunoglobulin E, confirmatory for an allergen.
Each diagnostic technology gives us a unique piece of the big picture. Together, these definable, quantifiable measures provide a basis for early diagnosis and treatment decisions, as well as ways to measure treatment success.
- Sjö diagnostic test. This test, from Bausch + Lomb, combines four traditional biomarkers with three novel, propriety biomarkers to detect Sjögren’s syndrome.
Early detection allows for fast initiation of treatment. By switching to a mindset of a possible underlying cause of contact lens intolerance vs. product changes, we can keep patients happy and in the lenses they prefer. OM