Rx Perspective
Enhancing Dry Eye Therapy
Patient education and involvement are crucial to success.
COORDINATED BY PAUL N. SCHACKNOW, M.D., PH.D.
THIS MONTH'S COLUMN WRITTEN BY CLIFFORD SALINGER, M.D.
Dry eye syndrome has a significant impact on our patients' daily lives. This is becoming more obvious as the frequency of their complaints increases. Not a day goes by in our practices when we're not asked about burning or stinging, a sandy or gritty feeling, or vision fluctuation, with or without light sensitivity, frequently encountered after 20 or 30 minutes of concentrated visual tasks.
It's clear that these patients no longer want to be "aware" of their eyes; they want to return to the ocular comfort they used to take for granted.
Furthermore, the effects of dry eyes on overall ocular health are underappreciated. Therefore, we should be actively treating these patients.
Our improved understanding of the tear film (that it's multilayered, and the layers interact and have their own origins and biochemistries) and the neurologic innervation controlling tear production and flow have resulted in better therapies for improving the ocular surface environment. So, moderate threats to tear film and ocular surface homeostasis are now more amenable to treatment.
GETTING PATIENTS INVOLVED
However, we can't maximize the efficacy of our current treatments unless our patients are actively involved in their dry eye care. The key to getting patients involved in their care is education. A team approach, involving you and your staff members, is essential in assuring your patients' long-term compliance with any regimen of dry eye therapy.
In our practice, we're able to get approximately 75% of our patients committed to and involved in their care. Of those patients, 70% to 80% see significant improvement in their symptoms, and we see similar improvement in their ocular surface signs with 6 to 8 weeks of treatment. Patients who don't become actively involved in their care continue to experience discomfort. When working with patients, we emphasize:
Paying attention to environment. Patients can control many environmental factors they encounter every day, which would make a significant difference in their comfort level. For example, air currents blow at them continuously throughout the day, causing evaporation of the tear film, but they can often choose where they sit relative to air conditioners and fans, run them at lower speeds, or direct the air currents away from their eyes. We remind them that this is a factor at night, too. They're already producing a lower volume of tears at night, and surface exposure may occur during rapid-eye- movement sleep.
Because computer screen height is a significant factor in the amount of ocular surface exposure and evaporation, we recommend that our patients raise themselves or lower the screen height so that they're looking downward slightly, resulting in less space between the eyelids.
Hot compresses/lid hygiene. Environmental exposures can be more easily tolerated if we improve the quality and consistency of our patients' tear film. The outer lipid layer, which is deficient in meibomian gland dysfunction, is critical to tear film stability and control of the evaporative component.
We emphasize the importance of hot compresses, which heat and melt inspissated material deep in the gland. The heating and melting begin only after 5 minutes of application, so we recommend 15-minute applications (hoping for 10 to 12 minutes) two to three times a day for at least 6 to 8 weeks, and then once a day for maintenance therapy. Many patients find that using a microwavable gel pack, wrapped in a moist washcloth for safety and better heat penetration, is more convenient.
Lid hygiene also helps to remove debris along the lid margin, which blocks the orifices. Massaging the lids further helps to move the meibomian material and increase blood flow to the area along with its inherent benefits. Patients can be instructed to use cotton swabs moistened with tap water. Eyelid scrub pads are available over the counter for patients who prefer not to use cotton swabs near the eye.
We don't recommend Johnson's Baby Shampoo! It can further disrupt a tear film that already can't dilute all the "soaps" in it, as evidenced by the bubbles we sometimes see in the tear lake.
Antibiotic ointment. We do recommend application of antibiotic ointment at bedtime to decrease the population of Staphylococcal organisms along the lid margin, which change the way the oils are "esterified," further disrupting their flow. Doxycycline or Minocycline can be given for more serious conditions or in cases of Rosacea.
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ILLUSTRATION: NICK ROTONDO |
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CURRENT AND FUTURE MODALITIES
Improved ocular surface protection by creating a better quality tear film may also allow the conjunctiva to better repair itself and increase the population of mucin-producing goblet cells, further improving tear-film sufficiency. Mucin improves the ocular surface tension, the reverse of what wax does for our cars, allowing for better coverage or spreadability of the tear film over the epithelial cell surface. Topically applied products that contain Vitamin A appear to possibly enhance this process.
Other growth factors important in ocular surface health are under neurologic and/or hormonal control and are only recently becoming understood. Therapies are being researched to control the production and release of these factors and better help our patients. Some promising areas of research include the use of testosterone analogs for the enhancement and preservation of lacrimal gland function. In addition, epidermal growth factors are being looked at for their ability to aid in the regeneration of ocular surface tissue.
Acute or chronic inflammatory conditions also upset tear film homeostasis. We can control many of these conditions with steroids, tailoring potency and frequency to the severity of the presentation. With the currently available wider array of "designer" steroids, we're better able to choose the appropriate therapy.
I often use steroids on a short-term or occasional basis in acute or chronic conditions where the inflammatory component is contributory. This returns the tear film and ocular surface environment to a more normal condition. Be prepared, however, to explain to patients why you won't always prescribe the "magic drop" they used at the beginning of their treatment program.
When dry eye is related to aqueous deficiency, I'm more likely to treat with tear substitutes or punctual occlusion than by trying to affect aqueous production. Newer tear substitutes attempt to more closely resemble the chemical and pH balance of the natural tear film, with gentler or no preservatives. They allow for more frequent use with little or no toxic side effects.
Punctual occlusion increases the volume of the aqueous component on a more steady-state basis, and new plug designs that are better tolerated and remain in position at the punctal orifice give us the luxury of easier reversibility. Be aware, however, that the increased tear film stasis might increase symptoms and signs of ocular allergic conditions.
Autoimmune conditions, including Sjogren's syndrome, by virtue of their effect on the lacrimal gland, lead to reduced aqueous production and flow. Therapies currently under investigation, notably cyclosporine, are believed to be beneficial in these conditions. They seem to slow cell death within the tear gland when immune-mediated and possibly decrease the rate of pre-programmed (apoptotic) cellular mortality.
WE CAN MAKE A DIFFERENCE NOW
Eventually we'll have more sophisticated weapons in our battle against the severe and chronic dry eye conditions that lead to visual compromise, which in turn will assist us in less severe cases. In the meantime, we can make the best use of current therapies by educating our patients more fully and convincing them to become active participants in their care.
Dr. Salinger is a fellowship-trained cornea and external disease specialist. He is Medical Director of the VIP Laser "Eye" Center in Palm Beach Gardens, Fla. He also teaches internationally with ORBIS International.