Characteristics of Tear Film in Sjögren's Syndrome Patients as Measured by a Novel Tear Film Imager: A Pilot Study.

Objectives: To investigate tear film characteristics in patients with Sjögren's syndrome (SS) and dry eye disease (DED) using the Tear Film Imager (TFI), focusing on comparisons to a matched control group and correlations between TFI parameters and clinical characteristics. Methods: This pilot cross-sectional study enrolled 15 patients with confirmed SS and DED and compared them to 15 age-matched healthy controls. Both groups underwent tear film imaging with the TFI. SS participants also completed clinical evaluations including the Ocular Surface Disease Index (OSDI), Schirmer's test, tear osmolarity, and tear breakup time (TBUT). TFI parameters included muco-aqueous layer thickness (MALT), muco-aqueous layer thinning rate (MALTR), lipid layer thickness (LLT), lipid map uniformity (LMU), lipid breakup time (LBUT), and interblink interval (IBI). Results: The study included 15 participants with SS (mean age 53.4 ± 15.1 years; 86.7% female) and 15 controls (mean age 52.3 ± 15.5 years; 73.3% female). SS participants exhibited significantly higher LMU (136.6 nm2 vs. 62.7 nm2; p = 0.034). Other parameters did not differ significantly. 60% of SS participants qualified for lipid-related DED versus 20% of controls. Schirmer's test scores positively correlated with MALT (ρ = 0.61, p < 0.05), while shorter IBIs correlated with greater symptom severity on the OSDI (ρ = -0.75, p < 0.05) amongst the SS group. Conclusions: Lipid layer heterogeneity, as measured by LMU, appears to be a key feature of SS-associated DED. Future studies should validate these findings and investigate lipid-targeted therapies.