Science is Catching Up
to Dry Eye
FROM THE CHIEF MEDICAL EDITOR,
Paul S. Koch, M.D.
About 15 years ago I set up a small dry eye clinic in my practice. I knew that patients with dry eye suffered out of proportion to our understanding of the disease, and I sensed we were on the verge of a solution. Unfortunately our tools were
limited. We had surface dyes and a culture plate on which we placed small paper discs saturated with tears. The inhibition effect of lysozyme on bacteria growth measured by the culture was felt to be an indirect measurement of tear secretion. After 6 months we closed up shop, mostly because it didn't make a difference. Everyone ended up using artificial tears no matter what we measured.
Jump forward to the present and the new concept in a dry eye clinic, as described in this month's cover story by Drs. Coffman and DeCanio (page 40). The tools have matured to actual chemical assay. The tear film can be analyzed for lactoferrin and for IgE. We are able now, for the first time, to say to patients with itchy, scratchy eyes: "Let's send a sample of your tears to the laboratory and see what we find." Our patients love that. After all, that's what their "real" doctors do.
Knowing the lactoferrin and IgE levels helps us decide whether the symptoms are caused by diminished tear secretion, overactive tear evaporation, or allergy. We can then focus our attention on targeted treatment.
For example, in our clinic we've measured improved lactoferrin levels following treatment with punctal occlusion and also following several weeks of nutritional supplementation. Prior to tear film analysis we were able to treat patients only by history and anecdote -- this seemed to work; this didn't. Now we have a way to scientifically measure and monitor a particularly vexing disease that has thwarted definition and cure.
Drs. Coffman and DeCanio have taken this information and are running with it. Perhaps we all should.
Ophthamology Management, Issue: November 2002