Ocular Surface Changes in Primary Open Angle Glaucoma with Long Term Topical Anti Glaucoma Medication

BackgroundTopical life long anti glaucoma medication forms the mainstay of treatment of primary open angle glaucoma. Their long term usage can cause changes in conjunctival epithelium.MethodsHundred cases of primary open angle glaucoma were divided into four groups of 25 patients each. Each group was put on Timolol, Pilocarpine, Brimonidine and Latanoprost respectively. Ocular surface changes were monitored using Schirmer's test, tear film break up time (BUT) and conjunctival impression cytology.ResultAltered Schirmer's test value was seen in 40% of patients and reduced tear film BUT values in 26%, at the end of one year. These changes were more in patients treated with timolol. Changes in conjunctival cytology such as decrease in goblet cell density, squamous metaplasia and presence of inflammatory cells were seen in significant number of patients at the end of one year treatment. There was direct relation of duration of treatment to various ocular surface changes.ConclusionOcular surface changes are seen in significant number of patients of primary open angle glaucoma at the end of one year follow up with topical anti glaucoma therapy. Conjunctival impression cytology is a non invasive technique to monitor these changes.