FIGURE 1.

Overlap of symptoms in dysfunctional tear syndrome (DTS) subtypes. There is a substantial overlap in the patient-reported symptoms of the types of DTS. Patients with subtypes of aqueous deficiency, blepharitis/meibomian gland dysfunction (MGD) – evaporative and nonevaporative – goblet cell deficiency/mucin deficiency, and exposure-related forms of DTS, including exposure keratopathy, may report symptoms of ocular discomfort, dryness, burning/stinging, grittiness or a foreign body sensation, photophobia, and blurred/fluctuating vision. Clinical evaluation with a battery of assessments and diagnostic techniques are needed for a differential diagnosis.