OXIDATIVE REACTIONS IN THE TEAR FLUID OF PATIENTS SUFFERING FROM DRY EYES

Purpose: To evaluate whether products of oxidative and inflammatory re actions are detectable in the lear fluid of patients suffering from dr y eyes. Methods: The tear fluid of 217 patients (397 eyes) was sampled . Criteria for grouping of the patients were (I) basic secretion test (''sicca 1'': BST = 0-5 mm, n = 78 eyes; ''sicca 2'': BST = 6-10 mm, n = 109 eyes) and (2) subjective symptoms (normal BST, burning, foreign body sensations, tearing, dryness of the eyes: n = 78 eyes). One grou p of healthy patients (normal EST, n = 132 eyes) served as controls. L ipid peroxide levels and myeloperoxidase activity, as parameters for o xidative tissue damage and inflammatory activity, were determined in t he tear fluid. Those patients whose consent could be obtained were sub jected to the rose bengal test (sicca 1: 56 eyes; sicca 2: 97 eyes; su bjective symptoms: 44 eyes; controls: 49 eyes). The correlation betwee n BST and rose bengal test results was calculated. Results: Lipid pero xides were significantly (P < 0.05) higher in the groups sicca 1 and s ubjective symptoms than in healthy controls, as was the inflammatory a ctivity in groups sicca 1, sicca 2 and subjective symptoms. Additional ly, the inflammatory activity in the group sicca 1 was significantly ( P < 0.05) higher than in the groups sicca 2 and subjective symptoms. N o evidence of a significant correlation between BST and rose bengal te st results was observed. Conclusions: Both oxidative tissue damage and polymer phonuclear leukocytes indicating an oxidative potential occur in the tear film of patients suffering from dry eyes. These reactions lead to severe damage of the involved tissue. Free radicals and infla mmation may be involved in the pathogenesis or in the self-propagation of the disease.