Infrared Imaging of Meibomian Glands and Evaluation of the Lipid Layer in Sjogren's Syndrome Patients and Nondry Eye Controls

Abstract

Purpose.: The purpose of this study was to evaluate meibomian gland dropout and lipid layer thickness (LLT) in patients with and without Sjögren's syndrome dry eye (SS). Methods.: We recruited 11 participants with SS (males/females [M/F], 1:10; mean age = 56.0 ± 9.1 years) and 10 control subjects without dry eye (M/F, 3:7; mean age = 58.5 ± 4.7 years). All participants completed the Ocular Surface Disease Index (OSDI) questionnaire. The LLT was assessed using the Tearscope Plus based on the appearance of the lipid layer. Noninvasive tear break-up time (NITBUT) also was measured. The lower and upper lids were everted, and the meibomian glands were imaged using the infrared camera of the Keratograph 4. A meibomian gland dropout score due to gland loss was obtained. Statistical analysis was conducted using the Mann-Whitney U test and correlations were determined using Spearman rank correlations. Results.: Of the SS participants, 100% reported ocular and oral dryness symptoms in the AECC questionnaire. The SS group recorded a higher OSDI score (median = 48.00, interquartile range [IQR] 23.0–56.2 vs. 2.1, IQR 0.0–2.6; P < 0.001), reduced LLT (median [IQR] = 15.0 [15.0–15.0] vs. 60.0 [45.0–100.0] nm; P = 0.001), and lower NITBUT (median [IQR] = 3.7 [2.5–4.2] vs. 9.5 [6.4–17.6] sec; P < 0.001) compared to the controls. Digital meibomian gland dropout score (% dropout) was significantly higher for the SS group (16.0% [IQR 12.1–40.0%] vs. 6.7% [IQR 1.5–12.7%]; P = 0.01). Subjective meibomian gland dropout score (0–6 score) was significantly higher for the SS group (median [IQR] = 1.5 [1.0–4.0] vs. 1.0 [0.0–1.25]; P = 0.03). Conclusions.: Patients with SS showed higher meibomian gland dropout scores and reduced LLT and NITBUT, which likely contribute to the severe dry eye symptoms reported by SS subjects.