Many of the contact lens modalities available today have been engineered with the goal to improve comfort. For instance, lenses that are more hydrophilic in nature may be friendlier to the ocular environment and, in particular, to the ocular surface. Some platforms promise better breathability, thus increasing the chance for the eye to function as though it does not have a foreign body on it providing refractive correction. Newer care solutions and cleaning regimens—and even daily disposable modalities—are geared toward improving ocular comfort so as to provide the best possible environment for all-day wear.
However, I wonder whether some of these high-technology solutions are the right fix for the wrong problem in many cases.
In a lot of ways, the improvements in contact lens technology make rational sense. Roughly 20% of patients drop out of contact lens wear, with discomfort being the predominant reason why.1 Ocular dryness is often cited as a contributing factor in comfort and wear issues. It makes intuitive sense, then, to develop lenses that minimize the potential to contribute to dryness symptoms, which in turn contribute to discomfort and eventual dropout.
Such thinking, though, misses this point: no matter how you spin it, a contact lens is a foreign body on the eye. Regardless of how well a contact lens is manufactured—whether it is considered non-irritating or comfortable or more hydrophilic in nature—it is always a non-organic material placed into the ocular environment with the potential to perturb ocular surface physiology and homeostasis. The use of certain lens modalities is associated with an elevation of interleukin-6 and interleukin-8, which are key inflammatory mediators in dry eye.2
The bottom line is that if a patient is borderline in terms of ocular surface health before starting lens wear, he or she will most certainly “develop” dry eye as a result. So why are we focused on putting uncomfortable patients into high-technology lenses that merely kick the can down the road when we should perhaps be thinking about diagnosing and treating dry eye before fitting contact lenses?
A BRIEF SNAPSHOT OF CONTACT LENS PATIENTS
Patients being fitted for contact lenses essentially fall into three categories. First are patients who have undiagnosed and/or untreated dry eye. These are likely candidates for dropout if their condition is not properly addressed regardless of modality. Putting patients who have an unhealthy ocular surface into contact lenses is very much an exercise in futility because their condition will almost inevitably cause a discomfort issue.
The second category consists of patients who have borderline ocular surface health in which a contact lens is going to push them over the edge. Patients who have mild and very early dry eye likely fall into this category as well—they may have some early signs, but symptoms are not consequential enough to cause immediate discomfort even when exacerbated by contact lens wear. Chances are that they will return to the office at some point complaining of fluctuating vision or a lack of comfort with their lenses late in the day.
The third category consists of patients who have no signs or symptoms of ocular surface issues but are at risk for developing dry eye simply because they want to wear contact lenses.
The problem is that it is impossible to know which category a given patient falls into unless we look at the ocular surface and ask about potential symptoms. We also know that given the potential to induce up-regulation of relevant dry eye mediators with regular contact lens wear, it behooves us to diagnose and treat any issues before prescribing contact lenses. At the very least, assessing the ocular surface before a fitting gives us a baseline for comparison should an issue arise later.
ASSESSING THE OCULAR SURFACE BEFORE A FITTING
Not all patients who wear contact lenses will develop dry eye. Contact lenses are merely a risk factor; a host of environmental and individual characteristics may or may not be factors in the development of true dry eye disease. However, dry eye is a chronic and progressive entity, and if it is not discovered and treated, it will get worse over time. In contact lens patients, lens wear is simply another contributing factor that could exacerbate or trigger signs and symptoms of ocular surface disease.
Neither are advancements in contact lens technology something that we should discount. In fact, using daily disposables and more hydrophilic platforms are associated with a lower risk of dry eye. For the category of patients who have no ocular surface issues at baseline, these newer lenses might make it possible for them to wear contact lenses for a lifetime without any issues. On the other hand, for those who have undiagnosed dry eye or borderline ocular surface health, simply moving them to a “more comfortable” contact lens will not address the underlying issue.
But, again, we do not know where a patient stands unless we take the time to look at the ocular surface, assess its health, and direct interventions as needed. In our practice, we make it a priority to assess the ocular surface prior to a fitting. Start with questionnaires if time permits; at a minimum, either the technicians or practitioners should ask questions directed at unmasking any symptoms, such as “Do you ever experience fluctuations in vision?” Fluorescein staining evaluation should be a fairly routine part of the work-up, and if there is any doubt, consider assessing tear osmolarity or matrix metalloproteinase-9 levels to gather objective information about the tear film and the state of the ocular surface.
Most of our patients are receptive to and appreciate the extra steps that we take to assess the health of the ocular surface, even if it means delaying the fitting. This is akin to working with a surgical candidate to unmask dry eye prior to surgery. We have found that it is better to assume that there is an issue and to rule it out than to assume that the eye will support contact lens wear only to discover an issue after the fitting.
In terms of treatment, cyclosporine ophthalmic emulsion 0.05% and lifitegrast ophthalmic solution 5% are highly effective for treating dry eye. In most cases in our practice, we initiate therapy when dry eye signs or symptoms are discovered in a pre-fitting workup, and patients are then typically able to successfully wear contact lenses. Obviously, more serious dry eye manifestations will require an elevation of treatment, and concomitant issues, such as meibomian gland dysfunction or blepharitis, might require targeted interventions.
We also have patients in our practice who developed dry eye while wearing contact lenses. In a lot of cases, we have been able to successfully maintain or resume lens wear. But, we do not get there only by changing the wear modality; those success stories are a result of treating underlying dry eye so that they have a better chance of comfort with the new contact lens that we prescribe.
CONCLUSION
Newer contact lens platforms do help to mitigate the risk of dry eye/comfort issues, but they do not eliminate the risk completely. Therefore, it behooves us to recognize any ocular surface issues that might progress prior to a fitting, in large part because dry eye does not have to be a contraindication to contact lens wear. In fact, newer lens modalities make it much more likely that patients who have dry eye or other issues can successfully wear contact lenses. Practitioners just need to make sure that their patients are given the best chance for success. That means that we should be looking for and treating the issues affecting patients and not just switching modalities to prolong the inevitable. CLS
REFERENCES
- Nichols JJ, Willcox MDP, Bron AJ, et al. The TFOS International Workshop on Contact Lens Discomfort: executive summary. Invest Ophthalmol Vis Sci. 2013 Oct 18;54:TFOS7-TFOS13.
- Poyraz C, Irkec M, Mocan MC. Elevated tear interleukin-6 and interleukin-8 levels associated with silicone hydrogel and conventional hydrogel contact lens wear. Eye Contact Lens. 2012 May;38:146-149.