Participants were randomised to receive benzalkonium chloride-containing latanoprost (Xalatan) or preservative-free bimatoprost (Lumigan). Through this study, the investigators would like to analyze the impact of different antiglaucoma medications on ocular surface disease in glaucoma patients.

The purpose of our study is to assess the effect of antiglaucoma medication on ocular surface disease in glaucoma patients before and after treatment with different antiglaucoma medication. All included patients are newly diagnosed with glaucoma and received no previous antiglaucoma treatment. Medical records will be collected prospectively from Sep. 15th 2019 to Aug. 31st 2022. The symptoms and signs of ocular surface disease in each individual will be assessed with questionnaire and clinical exams, including the basal Schirmer's test, non-invasive tear film breakup time, meibography, and in vivo confocal microscopy before and at 1, 3, 6 months after treatment.

Inclusion Criteria:

• Patients are not diagnosed with glaucoma and don't receive any ocular hypotensive eye drops at our clinic.
• Patients accept the rules for follow-up visits for at least six months.

Exclusion Criteria:

• Patients are with a history of ocular trauma.
• Patients are with contact lens use.
• Patients are diagnosed with secondary glaucoma.
• Patients have significant diseases affecting the meibomian gland and ocular surface.
• Patients have poor IOP control that required additional ocular hypotensive eye drops.

Patients were considered eligible for enrolment if they were newly diagnosed with glaucoma and started to receive ocular hypotensive eye drops at our clinic.