Ocular surface alterations and topical antiglaucomatous therapy: a review

Ocular Surface Disease (OSD) is prevalent among medically treated patients with glaucoma. This is basically related to three key-points: OSD and glaucoma are both prevalent in elderly and are common comorbidities in the same patient; the role of the active ingredient of the medical antiglaucomatous therapy; the role of the preservative agent of this medical therapy. Considering the actual state of literature we can state that the active glaucoma agent have a role in OSD, but the main cause seems to be the preservative agent, in particular referring to benzalkonium chloride, BAK. In the clinical evaluation of dry eye patients there is no actually established gold standard. Since the ocular surface injury not only causes dry eye, red eye, eye itching, photophobia and other discomforts, but also increases the risk of failure of glaucoma surgery in patients, it becomes fundamental a complete and good clinical evaluation of OSD (considering Schirmer's test, tear breakup time, corneal and conjunctival staining) together with a good evaluation of patients' quality of life (with validated questionnaires). Development of complex preparations, preservative-free and/or novel preservative preparations for glaucoma therapy could provide a promising approach in the prevention of ocular surface injuries.