Effects of osmoprotection on symptoms, ocular surface damage, and tear film modifications caused by glaucoma therapy

Purpose. To determine the effects of 2 artificial tear formulas on the ocular surface in patients with glaucoma using topical preserved beta-blockers (BB) or prostaglandins (PG).Methods. This was a prospective, comparative, randomized, double-blind study with a crossover design. Twenty patients with dry eye were divided into 2 groups based on glaucoma treatment: BB (10 subjects) or PG (10 subjects). Each group was administered a 4-week course of unpreserved isotonic (300 mOsm/L) solution containing 0.2% sodium hyaluronate (SH) or a preserved isotonic (295-305 mOsm/L) solution containing 0.5% carboxymethylcellulose and 0.9% glycerin as compatible solute (CMCs) administered QID. After a 2-week washout period, the course of treatment was reversed. The primary efficacy criteria consisted of assessing symptoms according to the Ocular Surface Disease Index^© (OSDI); the secondary efficacy criteria consisted of evaluating tear film confocal microscopy, central corneal thickness (CCT), and lissamine corneal and conjunctival staining (Oxford Grading System Score [OGSS]). Results. Within each group, only CMCs induced a significant improvement in OSDI and OGSS compared to baseline values: OSDI -20.5, p