BLOG: Measuring dry eye symptoms — SANDE doesn’t measure up
The most important measurement in treating dry eye is patient symptoms. Remember? You have to know what’s bugging them so you know what to fix. It’s helpful to know how much it’s bugging them so you know how well you are doing with your treatment. Whenever I lecture on dry eye or consult with a practice on starting up a dry eye service (shameless plug: I’m available!), I always ask the folks I’m addressing to tell me what kinds of complaints they hear from dry eye patients. My audience always misses the No. 1 and No. 2 complaints. No. 1 is — wait for it — "my eyes are dry." Duh. No. 2 as we learned from the PROOF study is some variation on "my vision is blurry."
It’s important to be on the lookout for as many symptom tip-offs as possible, either in the patient history or on your dry eye questionnaire. For sure, you need to at least ask about dryness and blurry vision. In July’s Ophthalmology, Amparo and colleagues propose the use of the SANDE test as an alternative to the OSDI. They are especially enthusiastic about how quick and intuitive the SANDE test was. For those of you not familiar, SANDE asks only how often your eyes feel dry or irritated and how severe are your symptoms.
Here’s the problem: The investigators recruited a cohort of patients with a dry eye diagnosis already made, some on the basis of blurred vision. In other words, because you don’t ask about blurred vision, you can’t use the test you are evaluating to identify test subjects who can evaluate your test. That’s a problem. If your dry eye patient suffers mainly from blurred vision, or perhaps eye fatigue, how is SANDE a valid measurement of symptoms, let alone a vehicle to raise the possibility of dry eye as a potential diagnosis in the first place?
I do like the quickness and simplicity, and I really like the visual analog scale (note to OSDI and SPEED users — this would be a cool version of either on an interactive website). Still, the information gathered is too superficial. Even rudimentary dry eye care requires not only a view below the surface, but one that will tell me if I’m seeing a mermaid or a monkfish in addition to telling me how big it is.
Amparo F, et al. Ophthalmology. 2015;doi:10.1016/j.ophtha.2015.02.037.