RESUMEN
<p><b>BACKGROUND</b>Long-term use of benzalkonium chloride (BAC)-preserved drugs is often associated with ocular surface toxicity. Ocular surface symptoms had a substantial impact on the glaucoma patients' quality of life and compliance. This study aimed to investigate the effects of sodium hyaluronate (SH) on ocular surface toxicity induced by BAC-preserved anti-glaucoma medications treatment.</p><p><b>METHODS</b>Fifty-eight patients (101 eyes), who received topical BAC-preserved anti-glaucoma medications treatment and met the severe dry eye criteria, were included in the analysis. All patients were maintained the original topical anti-glaucoma treatment. In the SH-treated group (56 eyes), unpreserved 0.3% SH eye drops were administered with 3 times daily for 90 days. In the control group (55 eyes), phosphate-buffered saline were administered with 3 times daily for 90 days. Ocular Surface Disease Index (OSDI) questionnaire, break-up time (BUT) test, corneal fluorescein staining, corneal and conjunctival rose Bengal staining, Schirmer test, and conjunctiva impression cytology were performed sequentially on days 0 and 91.</p><p><b>RESULTS</b>Compared with the control group, SH-treated group showed decrease in OSDI scores (Kruskal-Wallis test: H = 38.668, P < 0.001), fluorescein and rose Bengal scores (Wilcoxon signed-ranks test: z = -3.843, P < 0.001, and z = -3.508, P < 0.001, respectively), increase in tear film BUT (t-test: t = -10.994, P < 0.001) and aqueous tear production (t-test: t = -10.328, P < 0.001) on day 91. The goblet cell density was increased (t-test: t = -9.981, P < 0.001), and the morphology of the conjunctival epithelium were also improved after SH treatment.</p><p><b>CONCLUSIONS</b>SH significantly improved both symptoms and signs of ocular surface damage in patients with BAC-preserved anti-glaucoma medications treatment. SH could be proposed as a new attempt to reduce ocular surface toxicity, and alleviate symptoms of ocular surface damage in BAC-preserved anti-glaucoma medications treatment.</p>