Evaluation of tearing in oculoplastics assisted by tear osmolarity measurement

To determine the tear osmolarity in patients with tearing secondary to dry eye and other pathologies, and to determine the prevalence of dry eye disease among patients with tearing in an oculoplastics setting.

108 eyes of 54 patients with a chief complaint of tearing were prospectively recruited. Subjects were excluded if they used eye drops or contact lenses within 2 hours of assessment, had a history of refractive surgery, an active ocular allergy, or evidence of a systemic disease which affects tear production. A full medical and ocular history was taken with a complete eye exam pertinent to dry eye. Tear osmolarity was measured using the TearLab device. A clinical diagnosis of dry eye was made based on findings, without reference to tear osmolarity.

Among 86 eyes symptomatic for tearing, 32 eyes had dry eye disease (37%). Patients with dry eye had a significantly higher median tear osmolarity compared to that in patients with other diagnoses (308 mOsm/L vs. 294 mOsm/L, p < 0.0001). At a cut-off of 308 mOsm/L, tear osmolarity resulted in a sensitivity of 50% and a specificity of 88% for the diagnosis of dry eye.

A significant proportion of patients with tearing in an oculoplastics practice had dry eye disease. The high specificity of tear osmolarity may render it a useful tool to rule in dry eye disease and may assist the oculoplastic surgeon in more accurately determining the cause of tearing.