Effects of Topical Antiglaucoma Application on Conjunctival Impression Cytology Specimens

Purpose: To evaluate the changes in conjunctival impression cytology specimens from patients receiving various topical antiglaucoma medications. Design: Cross-sectional comparative study. Methods: Impression cytology specimens were obtained from the eyes taking no topical medication (n = 20) and from the eyes taking various antiglaucoma medications (timolol n = 34; latanoprost n = 40; dorzolamide n = 32; timolol + latanoprost n = 30; timolol + dorzolamide n = 34). Specimens were graded on a scale of zero to three according to Nelson's method. Results: Cytology scores were significantly higher in the medication group than the control group. Mean cytology scores of the control, timolol, latanoprost, dorzolamide, timolol + latanoprost, and timolol + dorzolamide group were 0.20, 1.62, 2.00, 1.75, 2.13, and 2.44, respectively. Among the medication groups, cytology scores were significantly lower in the monotherapy group than the fixed-combination therapy group. Conclusions: Various topical antiglaucoma medications induce a significant degree of squamous metaplasia. Conjunctival surface could be altered after the long-term use of antiglaucoma medication.