Clinical Significance of Tear Film Osmolarity for Non-Sjögren Dry Eye Diagnosis

ABSTRACT

PURPOSE: To evaluate the diagnostic value of tear film osmolarity for non-Sjogren dry eye syndrome through measuring the correlation between tear osmolarity and several conventional dry eye parameters. METHODS: In this observational cross-sectional study, 274 patients (274 eyes) with non-Sjogren dry eye syndrome were examined using tear film osmolarity and the following conventional dry eye parameters Schirmer's test, tear film break-up time, ocular surface disease index (OSDI), and corneal staining score. The correlations between tear film osmolarity and each conventional dry eye parameter were assessed using Spearman's correlation coefficients. RESULTS: The mean tear film osmolarity of the study population was 296.34 ± 21.08 mOsm/L. The tear film osmolarity was significantly negatively correlated with the Schirmer's test value (r = -0.431, p < 0.001) and tear break-up time (r = -0.131, p = 0.031), while it was significantly positively correlated with the OSDI scores (r = 0.191, p = 0.001) and corneal staining scores (r = 0.150, p = 0.013). CONCLUSIONS: Tear film instability was significantly correlated with other conventional dry eye parameters. However, additional studies are required to determine its feasibility as a stand-alone diagnostic tool.