point
TOPIC: Managing Lens-Related Dry Eye
Consider Treating Lens-Related Dry Eye With Pharmaceuticals
By S. Barry Eiden, OD, FAAO
More than 35 million people in the United States and more than 125 million worldwide currently are wearing contact lenses (Nichols, 2011). Unfortunately almost as many people drop out of lens wear annually as there are new wearers (Nichols, 2011). The most common complaint and reason for contact lens dropout continues to be comfort problems due to lens-associated dryness symptoms (Richdale et al, 2007).
Our understanding of dry eye disease has exponentially increased over the past number of years. Our ability to differentially diagnose various forms of dry eye has also allowed us to more specifically and effectively manage this common eye disease. The fact that some dry eye patients express symptoms only when wearing contact lenses has resulted in the diagnostic sub-category known as “contact lens-associated dry eye” (CLADE). Our patients' desire to remain in contact lenses should motivate us to explore any and all options available to manage this problem.
Current Approaches Fall Short
When asked about the management approaches most commonly utilized by practitioners to address CLADE, pharmaceutical agents fall very low on the chart (Nichols, 2010). Modifying contact lens material, care systems, and the use of lubrication agents are by far the most commonly used treatment strategies. Based upon the realities of our current contact lens-wearing population as it relates to CLADE, it seems quite obvious that we are not doing a very good job in addressing it. A change in our treatment approach is in order.
We now have a clear understanding of dry eye as a “multi-factorial disease of the tears and ocular surface that results in discomfort, visual disturbances, and tear film instability with potential damage to the ocular surface that is accompanied by tear film hyper-osmolarity and inflammation of the ocular surface” (Lemp et al, 2007). We also have come to understand the relationship of conditions such as blepharitis and meibomian gland dysfunction (MGD) in dry eye disease (Lemp and Nichols, 2009). In my opinion, our ability to treat CLADE can be dramatically improved by the medical management of these basic physiological anomalies. The use of pharmaceutical agents as part of the armamentarium can significantly increase our treatment success rates.
Successfully Managing CLADE
There are two key phases in the successful management of CLADE. Phase one is the diagnostic phase. It is imperative to properly diagnose cause(s) of the dry eye. Detailed examination of the anterior segment along with dry eye diagnostic techniques such as vital staining, tear meniscus height, tear breakup time, tear volume measurements, tear quality assessment, and tear film osmolarity measures are critical, as is a detailed dry eye history.
Phase two is the treatment phase. With our greater understanding of dry eye disease and the information obtained from phase one, we can tailor our treatment with greater success. Pharmaceutical agents that address blepharitis and MGD such as topical and oral macrolide antibiotics and topical steroid/antibiotic combination agents are highly effective. Short-term topical steroid therapy along with long-term nonsteroidal anti-inflammatory treatment (such as cyclosporine) have also shown great success. Future pharmaceutical agents are being developed that will further improve our ability to manage dry eye. Punctal occlusion procedures also have a place in CLADE therapy and have allowed many of our patients to continue to wear contact lenses successfully. CLS
For references, please visit www.clspectrum.com/references.asp and click on document #185.
Dr. Eiden, co-founder of Eye-Vis Eye and Vision Research Institute, is president of a private group practice in Illinois. He has a financial interest in Alternative Vision Solutions, LLC, is a consultant or advisor to Ciba Vision, CooperVision, SynergEyes, Alcon, and SpecialEyes, and has received research funds from Vistakon, CooperVision, and B+L.
counterpoint
Pharmaceuticals Aren't Always the Answer for Lens-Related Dry Eye
By Edward Williams, OD, FAAO
In my practice, dryness is the primary reason for contact lens failure. The decision to use prescription drug therapy is particularly complicated when asymptomatic patients desire contact lenses for cosmesis only and have no prior history of anterior segment disease. Let's look at a common clinical scenario and consider the pros and cons of prescription pharmaceutical intervention.
Pharmaceutical Considerations for a Common Patient
It's likely you've seen this type of patient: the surfaces and lashes of all four lid margins are smooth, clean, and uninflamed. His conjunctivas and corneas are flawless with no staining of the ocular surface by any dye. No meibum is expressible from the meibomian glands, and the tear breakup time (TBUT) is four seconds with lenses on the eye. You soon discover that this patient can't wear any type of lens comfortably with acceptable vision because he has nonobvious obstructive meibomian gland dysfunction (MGD) without apparent inflammation, the leading cause of evaporative dry eye (Blackie and Korb, 2010).
What are some currently available prescription treatment options for managing this case? Nonsteroidal immunomodulator drops are possible, but they may take three to six months to work with frequent side effects. As this patient is uninflamed unless he tries to wear contact lenses, there may be no clinical efficacy and there is little evidence to support their use.
Likewise for steroidal immunomodulator drops: although they might work rapidly and are relatively safe (Thomas and Melton, 2010), we have to consider the side effects in cosmetic lens wearers.
With nonobvious obstructive MGD, what we need is a “glandulomodulator,” a medication that stabilizes oil flow and production and reduces gland clogging. We could use the oral antibiotics that have beneficial side effects in improving meibomian gland function, but these also take time to work and may be associated with other unnecessary side effects. As our patient simply wants to wear cosmetic contact lenses, we may find this oral treatment a hard sell.
A better option might be the faster-acting topical antibiotic gel-forming drop that also acts as a glandulomodulator. There is evidence that this drug is associated with a decrease of meibomian gland plugging (Hague, 2010). Unfortunately, the same study also noted that a significant number of subjects had adverse events, albeit non-serious.
As always, any pharmaceutical treatment may be expensive; there are many questions as to how often patients need to use it, how long they will need to use it, whether they will use it as directed, and the associated side effects.
In the case of nonobvious obstructive MGD, efficacy is doubtful as well.
Is this patient doomed? What about non-pharmaceutical approaches? Nothing is strikingly successful. Punctal plugs sometimes help. Omega 3 supplementation may be beneficial. Over-the-counter moisture drops will improve in the future.
Many of us have unsuccessfully attempted to routinely express meibomian glands. There is interesting research in the area of gland expression involving a novel thermodynamic device (Korb, 2010). A 37-year-old dry-eyed patient had seen seven eye doctors in three years without relief. All of the meibomian glands in her lower right lid and all but one in her left were nonfunctional. After single 12-minute treatments per eye, this device restored function to eight meibomian glands per eye, doubling the TBUT from 5 to 10 seconds. This single treatment remained effective for the entire three-month follow-up period. Research in this direction may offer the patient that we've considered here the quick and effective therapy he needs, drug free. CLS
For references, please visit www.clspectrum.com/references.asp and click on document #185.
Dr. Williams is an optometrist in private practice in Denver, Colo.