Corneal thickness measurement is important for assessing intraocular pressure in patients with glaucoma. This study investigated the changes in corneal epithelial thickness (CET) induced by antiglaucoma medications and explored the factors affecting CET measurement. CET was measured over a 9.0 mm diameter area by using Fourier domain optical coherence tomography in 125 patients with primary open-angle glaucoma and 125 age-matched controls without glaucoma. The influence of sex, age, benzalkonium chloride (BAK)-containing instillations, disease severity, and types and numbers of medications was analyzed using simple and multiple regression analyses. CET over 25 sectors was smaller in the glaucoma group than in the control group (mean difference of 4.2 µm in the central 2.0 mm zone; 52.8 ± 3.6 vs. 48.5 ± 3.9, p < 0.001). Simple regression analysis revealed age, use of β-blockers, prostaglandin, carbonic anhydrase inhibitors, total number of medications, and number of daily BAK-containing instillations were associated with a thinner epithelium. Multiple regression analysis revealed β-blockers, prostaglandin, and number of BAK-containing instillations were significant factors. Use of β-blockers and number of BAK-containing instillations were also associated with a thinner epithelium in the monotherapy subgroup analysis. CET was significantly smaller in patients with glaucoma receiving topical medications and was affected by the use of β-blockers, prostaglandin, and BAK.

Purpose: This study investigates the intraocular pressures and dry eye signs before and after botulinum toxin (botox) injections for patients with essential blepharospasm.Methods: From November 2021 to July 2022, a prospective study examined 78 eyes of 39 patients diagnosed with essential blepharospasm. Before injection and 1 and 3 months after injection, intraocular pressures (IOPs) were measured using a Goldmann applanation tonometer. The noninvasive breakup time (NIBUT), lipid layer thickness (LLT), tear meniscus height (TMH), and meibomian gland clearance were assessed with the aid of the IDRA platform (SBM Sistemi, Turin, Italy).Results: The average IOPs were 14.33 ± 3.47 (7-21), 13.45 ± 3.54 (9-21), and 13.28 ± 2.98 (7-20) mmHg before, and 1 and 3 months after, botox injection respectively (<i>p</i> = 0.002 , <i>p</i> = 0.004). Twenty-four eyes of 12 patients with dry eye symptoms evidenced a significant difference in the NIBUT 1 month after Botox injection, but no significant difference in any of the LLT, TMH, or meibomian gland areal loss percentage (<i>p</i> = 0.007, 0.201, 0.586, and 0.435 respectively). After 3 months, no dry eye parameter change, including the NIBUT, was significant (<i>p</i> = 0.202, 0.542, 0.240, and 0.721 respectively).Conclusions: Botulinum toxin A injection temporarily relieved dry eye symptoms and reduced the IOP in patients with essential blepharospasm.