discovering dry eye
Seven "Truths" About Dry Eye Disease
BY KELLY K. NICHOLS, OD, MS, MPH
Many issues exist about which the dry eye community doesn't agree. But can we find some truths regarding dry eye disease that we can all agree on? As you read this list, you'll notice that some of the items are a stretch, others are humorous and the remainder a foregone conclusion. I invite every reader to pen a few of his own. Read on!
Dry eye exists. We've all diagnosed a patient (or many) with dry eye. Conservative estimates show that on average, for all types of patients, approximately one in 10 patients will have at least reportable dry eye symptoms. In addition, dry eye disease has an ICD-9 code (375.15), so if we can bill for it, then it must exist.
Contact lens wearers can have "contact lens-related dry eye" and be largely asymptomatic when wearing no correction or spectacles. (Last month's column featured the lissamine green conjunctival staining patterns found in such patients.)
Artificial tears help. I'm sure most of you are saying, "Come on now!" but the literature demonstrates definite improvements in symptoms, staining and goblet cell density with consistent artificial tear use. The key words here are consistent use.
If you can get a patient to actually use artificial tears as you prescribe them, then the symptoms will improve. We all know, however, that patients who have severe dry eye swear by them and patients who have mild to moderate dry eye often discontinue use when the sample you gave them runs out.
We now have medical management available. In case you've been out of the country since last April and missed the press, Restasis (cyclosporine ophthalmic emulsion 0.05%, Allergan) has arrived. In my experience and in the experience of my colleagues, Restasis has had a positive impact on many dry eye patients. Don't forget to consider this drug when dealing with dry eye cases.
Hormones have an impact on the ocular surface. Evidence has shown that androgens play a role at the level of the meibomian gland secretion, and that circulating hormones influence the regulation of the ocular surface- lacrimal gland feedback loop. Experts debate the effect of using hormone replacement therapy on dry eye, and women often change hormone replacement use during the menopause process, which complicates the issue.
Clinical tests for dry eye have been shown to be unreliable and largely don't correlate with dry eye symptoms, but you should perform them anyway to document the disease.
On the positive side, the tests tend to work better for more advanced cases of dry eye. Also, you may use some subtle markers of inflammatory dry eye disease, such as mild changes in conjunctival or lid margin redness, to later document improvement with treatment. Specific drawings of the location and type of corneal or conjunctival staining may also help. (All of you inventors out there should start thinking of new and innovative dry eye tests.)
Patients will tell you how their eyes feel (if you ask).
Truths are Truths
As I mentioned, this is my list, but it includes truths that I'm sure many of you can attest to. And because we can't change them, we may as well embrace them.
Dr. Nichols is assistant professor of clinical optometry at The Ohio State University College of Optometry in the area of dry eye research.