Conjunctival Microvascular Characteristics as New Ocular Surface Inflammatory Indicators in Mild Dry Eye

To explore the ability of conjunctival microvasculature in differentiating ocular surface inflammation (OSI) in mild dry eye (DE), and to guide adjunctive anti-inflammatory treatment in mild DE.
83 mild DE patients and 26 healthy controls were enrolled in a cross-sectional study. Mild DE patients were classified into those with OSI and those without based on Z-score level of tear cytokines. Differences in microvasculature and clinical manifestations were analyzed, alongside correlations with tear cytokines. A logistic regression model was developed for detecting OSI based on microvascular parameters. A secondary analysis of a RCT involved 35 mild DE patients with OSI to compare microvascular and clinical outcomes between treatment groups (adjunctive 0.05% Cyclosporine A vs. artificial tears alone).
Elevated blood flow velocity (BFV: 0.37 ± 0.04 mm/s) and wall shear rate (WSR: 170.98 ± 26.96 s−1) were found in mild DE with OSI than those without (BFV: 0.32 ± 0.03 mm/s, WSR: 145.90 ± 18.46 s−1, p < 0.01), while no significant differences were found in clinical manifestations. BFV and WSR were correlated with IL-6 (rBFV = 0.43, rWSR = 0.39, p < 0.05). The AUC - ROC for the mild DE-related OSI detection model based on BFV and WSR was 0.858. In mild DE with OSI treated with 0.05% Cyclosporine A, BFV, WSR, IL-6, clinical manifestations improved significantly at 12 weeks (p < 0.05).
Elevated BFV and WSR can facilitate early detection of mild DE-related OSI before changes in symptoms and signs, allowing timely anti-inflammatory intervention.