Aim or Purpose: The primary objective of this study is to describe the effects of application of topical timolol or latanoprost on the conjunctiva with the use of tear break-up test, Schirmer test and impression cytology; the secondary objective of this study is to evaluate the impact of dry eye symptoms on the quality of life among glaucoma patients.
Design: Prospective case series study.
Methods: All patients were asked to answer the ocular surface disease index (OSDI) questionnaire. Dry eye work-up consisted of tear break-up test, staining tests with fluorescein and Lissamine green, Schirmer test with anesthesia, and conjunctival impression cytology. Conjunctival samples were then examined, evaluated and their changes documented by a single ocular pathologist.
Results: A total of eighteen participants, including twenty eight eyes, fifteen in the timolol group and thirteen in the latanoprost group, were included in this study. Baseline characteristics were comparable between the two groups. There is a trend of decrease in tear break-up time with increasing duration of use of medication in the subgroup analysis for both the timolol and latanoprost groups. The latanoprost group showed a significant decrease in the Schirmer test but the timolol group did not. The conjunctival changes scores for the latanoprost group showed a significant increase with increasing duration of use of medication but the timolol group did not.
Conclusion: Increased duration of use of latanoprost showed significant goblet cell loss, as indicated by increased conjunctival changes score, and also a decreased Schirmer test result. Prolonged use of latanoprost showed significant increase in dry eye symptoms and severity as indicated by increased OSDI score. Long-term use of timolol showed no significant changes in OSDI score, TBUT score, Schirmer test result and conjunctival changes score.