Contact lenses and dry eye: Cause or remedy?

August 30, 2016

Article

Contact lens wearers are dropping out for comfort and vision reasons. Contact lenses can be considered a significant cause of these symptoms if they contribute to an unstable tear film or trigger inflammatory reactions.

On any given day of your practice, you may meet with one or more of the three following contact lens patient examples.

When you do, consider what they have in common and how they differ. Is there a logical link among these clinical entities? If yes, what can we learn from their management?

While these questions are important, the one question that should be asked every time is: Are contact lenses a cause or a remedy for these patients?

Case 1

M.H. is a 24-year-old African-American male. He is a manual laborer who is exposed to dust and particles daily. He presents for contact lens discomfort, which has been lasting for several months but increasing in recent weeks.

He has been buying his contact lenses from an online contact lens retailer and is wearing biweekly disposable lenses on a monthly basis.

Case 2

S.Y. is a 34-year-old Caucasian female who works on a computer eight hours per week. She had been fitted with contact lenses four years ago. Everything had been going well except that in the last six months she reported recurrent episodes of contact lens intolerance.

Since the beginning, she had been wearing senofilcon A (Acuvue Oasys, Johnson & Johnson Vision Care) lenses and she had never cleaned them with anything other than a Polyquad-based lens care solution.

Case 3

S.P. is a 39-year-old Latino male who underwent LASIK surgery 10 years ago. He resumed contact lens wear one year ago to improve intermediate and near vision. At this visit, he is complaining of not being able to tolerate his contact lenses for more than four hours per day.

What’s the common link among these patients?

These patients are not wearing the same type of contact lenses, do not share the same care regimen, do not live in similar environments, and their age, gender, and ethnic background vary. However, they are all complaining about discomfort and/or ocular dryness. While the circumstances are different for each patient, contact lenses can be considered a cause or a remedy to fix their problems.

Defining and tracking contact lens discomfor

According to the Tear Film and Ocular Surface Society (TFOS) Workshop, contact lens discomfort (CLD) is characterized by “episodic or persistent adverse ocular sensations related to lens wear, either with or without visual disturbance, resulting from reduced compatibility between the contact lens and the ocular environment, which can lead to decreased wearing time and discontinuation of contact lens wear.”

This clinical entity affects over 50 percent of contact lens wearers and is considered the primary reason for dropping out of lens wear in patients under 45 years old.¹

It is crucial to track signs and symptoms of CLD before symptoms reach the threshold where the benefits to wear contact lenses decrease. When this happens, patients simply decide to drop out, not knowing that other options exist.

Simple key questions to ask during case history can help to track the process. When are you applying and removing your lenses?

When would you like to remove them?

How is your vision in the morning, during the day, while doing computer work, driving at night?

Usually the most powerful question to ask is the last: If you could improve one aspect related to your contact lens experience, which one would it be? This answer is very important and must be addressed by the practitioner.

The quest for CLD continues with the identification of clinical signs, especially those that could be related to subclinical chronic inflammation:

Telangiectasia of the lower lids

Posterior blepharitis

Conjunctival redness

Chemosis or staining

Engorgement of the blood vessels and loss of corneal transparency at the limbus

Lower-third corneal staining

Lid wiper epitheliopathy (lissamine green staining)

Conjunctival papillary reaction

A combination of signs and symptoms should raise a red flag and prompt the practitioner to address these challenges.

Many intolerant contact lens wearers are marginal dry eye patients. This means that, without contact lenses, they present with an unstable tear film, driving symptoms when exposed to a specific and challenging environment.

The same individuals, fitted with contact lenses, become rapidly symptomatic of eye dryness and lens intolerance. Contact lenses should then be perceived as a cause that contributes moving an episodic condition to a chronic stage.

Treat the ocular surface first

Most practitioners will try switching patients from chemical multi-purpose care solutions to a hydrogen peroxide system as a first step. This can help for a short period, but symptoms will recur in the long term. The next step will be to eliminate the use of any solution by refitting the patient into daily disposable lenses.

Again, a short-term victory will be celebrated, but in some cases symptoms will remain. A better pathway would be to take sufficient time to evaluate accurately the ocular surface, restore it, and then consider refitting the patient with ocular-friendly contact lens options.

Managing our example patients

Let’s go back to the three example patients. How can we best manage these patients?

Case 1

The real cause of the patient’s symptoms here is not contact lenses per se. In fact, the patient’s inherent risk factors and noncompliance are contributing to degrade contact lenses and to lower their clinical efficacy (Figure 1).

In such cases, it is very difficult to change many bad habits at the same time. A step-by-step approach with proper patient education, is the basis for a successful long-term rehabilitation. This patient is stretching lenses for up to a month of wear.

Logically, it is preferable to fit him in a monthly disposable instead of a biweekly one. Because it is preferable to fit lenses to a patient rather than trying to fit a patient in a lens modality, high-Dk monthly disposable lenses can work. Alternatively, refractive surgery can represent a valid alternative.

Case 2

This is a typical contact lens-associated infiltrative keratitis (CLAIK) case (Figure 2). This type of adverse event is not related to the contact lenses but rather an interaction between the lenses and the care regimen. It has been characterized by wax and wane symptoms of lens intolerance, low conjunctival hyperemia, the presence of multiple non-infectious infiltrates associated with limited corneal staining and no haze around the infiltrates.

Related: Fitting ortho-k contact lenses

This reaction is an inflammatory response to trapped debris and toxins under the lenses. Mostly associated to the combination of senofilcon A lenses and Polyquad-preserved contact lens solution,2 it can also be seen with several other lens-solutions combinations. During lens wear, if the lens is not moving and tear mixing is not sufficient, bacterial toxins remain trapped and trigger an immune response clinically seen as the infiltrative keratitis. This keratitis will resolve in a few days with lubrication of the ocular surface only or even before if steroids are used.

As with other immune responses, recurrence is common, especially if the same lenses and the same solutions are resumed. It is mandatory to refit the patient with a lens that is moving. It is even better to consider daily disposable lenses to eliminate the use of solutions to limit the deposition on the lens surface and its contamination by pathogens.

Case 3

A fair number of post-refractive surgery patients are showing eye dryness symptoms because of a chronic alteration of the feedback loop, originating from the sensory nerves of the cornea.3 This chronic aqueous-deficient eye dryness impacts visual acuity, comfort, and ocular health. Soft contact lenses dehydrate due to evaporation, which contributes to increased symptoms.4

Aqueous-deficient dry eye should be treated aggressively by increasing lubrication, prescribing topical cyclosporine A (Restasis, Allergan) to enhance tear production, and finding contact lenses able to restore visual acuity.

Scleral contact lenses maintain a hydrated environment over the cornea and the conjunctiva, they do not dehydrate, and they are very effective to protect the eye from allergen exposure. Consequently, in this case, scleral contact lenses can be considered a remedy.

Take a closer look at your patients

Contact lens wearers are dropping out of this modality for reasons related mainly to comfort and associated dryness. Contact lenses can be considered a significant cause of these symptoms if they contribute to an unstable tear film or if they challenge the immune system to the point of triggering inflammatory reactions.

On the other hand, contact lenses, including scleral lenses, can help to restore ocular surface condition by regenerating a friendly and moist environment for the cornea and the conjunctiva.

Practitioners should proactively track potential contact lens dropout. Once found, these patients should be considered as marginal dry eye patients or very sensitive to the presence of deposits, pathogens, chemicals, or other elements able to trigger immune reaction.

It is important to reinforce the fact that any concern with the ocular surface should be treated before considering contact lens wear or as a first step to improve the contact lens wearing experience.

References

1. Nichols JJ, Willcox MD, Bron AJ, et al. The TFOS International Workshop on Contact Lens Discomfort: executive summary. Invest Ophthalmol Vis Sci. 2013 Oct 18;54(11): TFOS7-TFOS13.
2. Sacco AJ. Contact Lens-Associated Infiltrative Keratitis and Multipurpose Solutions. CL Spectrum. 2011 Apr. Available at: http://www.clspectrum.com/articleviewer.aspx?articleID=105455. Accessed 8/29/16.
3. Shtein RM. Post-LASIK dry eye. Expert Rev Ophthalmol. 2011 Oct; 6(5): 575–582.
4. Fonn D, Situ P, Simpson T. Hydrogel lens dehydration and subjective comfort and dryness ratings in symptomatic and asymptomatic contact lens wearers. Optom Vis Sci. 1999 Oct;76(10):700-4.