The power of numbers
In my view, point-of-care testing for dry eye disease has many advantages above and beyond helping us diagnose the problem. One enormous benefit is standardisation.
Tests are consistent, objective and not affected by the differences in perceptions among multiple physicians. A colleague and I may differ in our evaluation of the corneal epithelium or the appearance of the meibomian glands, but our tear osmolarity or MMP-9 test results will be identical.
Concrete numbers and images also help us explain dry eye disease to patients. They can clearly see that their number is not in the normal range for a given test, or see the atrophied meibomian glands we have identified. This evidence is a relief for patients who have suffered with dry eye and received little help.
For asymptomatic patients, objective tests offer proof that they have a problem. This is especially important for patients who are planning laser vision surgery. We explain that surgery reduces tear film production, so it is essential that we take the time to treat dry eye disease before surgery to avoid symptoms later. Based on the evidence, patients are very amenable to treatment.
Another advantage is that dry eye patients love to see their numbers go down. Once we have our baseline tests in our practice, patients begin treatment, possibly including pulsed light therapy (E-Eye, ESW Vision); prescription medications; artificial tears; warm compresses and other measures.
They see the numbers changing because of therapy, which has much more of an impact than simply hearing “I see the tear film is better than last month”. Some of these patients routinely get numbers for their diabetes or glaucoma, so they already have that mindset.
People like to know that their therapies, including the sometimes monotonous or inconvenient steps they take every day at home, are driving down their numbers. This makes point-of-care testing a powerful, effective tool to get patients on board and encourage them to maintain compliance with therapy. And compliance is essential for this chronic, progressive disease where symptoms improve only once the diagnostic numbers are regularised.