Adverse effects of topical antiglaucoma drugs on the ocular surface
Purpose: This study was designed to determine the effect of long-term antiglaucoma topical medication on the ocular surface; measuring basal Schirmer's and tear break-up time tests using conjunctival impression cytology. Methods: The ocular surfaces of 30 control subjects (group 1), 24 primary open-angle glaucoma patients treated with 0.5% betaxolol hydrochloride (group 2), 27 primary open-angle glaucoma patients treated with 0.5% timolol maleate (group 3) and 26 primary open-angle glaucoma patients treated with 0.5% betaxolol and 1% dipivefrin hydrochloride (group 4) were evaluated. Basal Schirmer's and tear break-up time tests were measured and ocular surface changes were determined by impression cytology. Impression cytology specimens of each group were graded and scored in the range 0-3 according to Nelson's method. Results: Patients in groups 2, 3 and 4 showed statistically significant fewer normal basal Schirmer's tests (wettability) and tear break-up time tests (P < 0.01). Also, the conjunctival impression cytology scores were significantly higher in groups 2, 3 and 4 than in group 1 (P < 0.01). Conclusions: The conclusion was that it is possible that conjunctival surface and tear film function change after the long-term use of antiglaucoma medication.