Happy New Year!

I hope everyone had a great holiday season and I want to wish everyone a healthy and prosperous 2012.

The dry eye newsletter will continue through 2012 and I'd like to thank EyeSupply USA for their continued sponsorship. Please take a moment to check out their product line.

Rehydrate Lenses
Last month we discussed dry eye in our contact lens patients. I ended that column recommending the use of artificial tears and contact lens rewetting drops. Also, advise your contact lens-wearing patients to frequently rehydrate their lenses. Here's an added thought: have your symptomatic patients remove their lenses about halfway through the day and place them in a storage case filled with fresh saline for a half hour while they rewet their eyes using non-preserved artificial tears. While it may be difficult to get your patients to try this approach, this regimen often allows lens wearers with more severe dry eye to extend their wearing time.¹

Is it the solution?
Consider that dryness symptoms may not stem solely from tear evaporation, especially if rewetting agents don't provide relief. Contact lens care products may be a cause of contact lens related intolerance and dry eye related symptoms. Some biguanide preserved solutions have been associated with increased corneal staining, decreased contact lens wearing time and cessation of contact lens wear.^2-4 Alternatively, you may want to consider changing the patient's lens care regimen to a hydrogen peroxide care system. Hydrogen peroxide systems ensure that the contact lens goes into the eye without any harsh preservatives that may disrupt the tear film. Or, consider eliminating the solution interaction altogether by switching the patient to a daily disposable lens. A fresh lens daily will not coat, become damaged or uptake harsh chemical preservatives.

Consider therapeutic intervention
The use of 0.5% cyclosporine A (Restasis, Allergan) in contact lens patients before lens application and after lens removal can also significantly increase comfortable wearing time.⁵ A study by Hom showed a significant reduction in contact lens intolerance with the use of Restasis when the emulsion was used before and after lens wear.⁶

Omega-3 fatty acids beneficially interact with the fatty acid metabolism of the meibomian glands, enhancing their glandular secretions.⁷ Omega-3 supplementation meets the clinical needs of many patients with dry eye syndrome in general, and ought to be considered in your contact lens patients who have dry eye symptoms. The two most common sources of omega-3 fatty acids are fish oil and flaxseed oil. Several vitamin products are available, including Fortifeye Complete Plus and Fortifeye Dry Eye Therapy from EyeSupply USA.

Time for a material change?
Consider changing the type of contact lens your patient is wearing to a silicone hydrogel lens. The high oxygen transmissibility of the silicone hydrogel contact lenses results in greater biocompatibility with the human eye in terms of less hypoxic changes in the cornea over time, reduced limbal redness, less sensitivity to low tear volumes plus greater overall comfort. The silicone hydrogels are low water content, high permeability materials for which evaporation and dehydration appear to be significantly less of a problem than with conventional hydrogels. The combination of low water content and high Dk/t may result in improved comfort for patients who had previously experienced dryness in thin, high-water content conventional hydrogel lenses. The high oxygen transmissibility of the silicone hydrogel lenses leads to better corneal health.⁸ Silicone hydrogel materials do not require the hydration that conventional hydrogels require on the eye, so marginal to moderate dry eye patients really appreciate the improved comfort with these lenses.

End-of-day dryness is one hallmark symptom of contact lens-related dry eye. There is noticeably improved end-of-day comfort and patients report increased wearing time with silicone hydrogel contact lenses. One study from 2004 showed significant improvement in contact lens wearing time in patients refit in silicone hydrogel contact lenses. The percent of the study contact lens patients who were able to wear their lenses for more than 12 hours per day went from 25% in conventional hydrogels to almost 65% in silicone hydrogel lenses. Patients who routinely worked on computers were also able to increase their wear time by almost two hours daily.⁹ Dryness symptoms decrease in both frequency and severity when hydrogel lens patients are refit into silicone hydrogels, even with extended wear.¹⁰

There are many causes of contact lens-related dryness. Manage any ocular surface and lid disease and monitor the stability of the tear film. Educate your patients on contact lens care and hygiene. Consider fitting patients in silicone hydrogel lenses with an appropriate lens care system to keep them comfortably wearing lenses. When patients are totally comfortable with their lens wear they tend to be more loyal to the practice, and loyal patients lead to a successful and profitable practice.

REFERENCES
1. Boland MR, et al. Troubleshooting dry eye. Rev Optometrist. 2002; 139:11.
2. Lievens CW, Hakim N, Chinn A. The effect of multipurpose solutions on the ocular surface. Eye Contact Lens. 2006; 32: 8-11.
3. Lebow KA, Schachet JL. Evaluation of corneal staining and patient preference with use of three multi-purpose solutions and two brands of soft contact lenses. Eye Contact Lens. 2003; 29: 213-220.
4. Jones L, MacDougall N, Sorbara LG. Asymptomatic Corneal Staining with the use of Balafilcon Silicone-hydrogel Contact Lenses Disinfected with Polyaminopropyl Biguanide preserved Care Regimen. Optom Vis Sci. 2002; 79: 753-761.
5. Nichols KK, Nichols JJ. The Latest Research and Treatment Options for Lens-Related Dry Eye. Contact Lens Spectrum. September 2006.
6. Hom MM. Use of cyclosporine 0.05% ophthalmic emulsion for contact lens-intolerant patients. Eye Contact Lens. 2006; 32: 109-111.
7. Miljanovic B, Trivedi KA, Dana MR, et al. Relation between dietary n-3 and n-6 fatty acids and clinically diagnosed dry eye syndrome in women. Am J Clin Nutr. 2005; 82(4): 887-893.
8. Caffery B. Silicone Hydrogels: A Clinical Look at Daily Wear with Silicone Hydrogels Lenses. Siliconehydrogels.org. http://www.siliconehydrogels.org/editorials/TMPolyjo5rkl.htm
9. Sickenberger W. Are silicone hydrogels suitable for dry eye conditions in a daily wear modality? Siliconehydrogels.org. Feb. 2004. http://www.siliconehydrogels.org/in_the_practice/inthe_practice_wolfgang_sickenberger.asp
10. Schafer J. Choosing Lens Materials to Solve Dryness Complaints. Contact Lens Spectrum. March 2006.