Effects of prostaglandin analog therapy on the ocular surface of glaucoma patients

Abstract

Purpose: To quantify changes in tear break-up time (TBUT), corneal staining and ocular surface disease index (OSDI) in glaucoma patients after switching therapy from latanoprost with 0.02% benzalkonium chloride (BAK) to travoprost with sofZia ™ . Methods: Prospective consecutive case series evaluating patients before and 8 weeks after switching from latanoprost with BAK to travoprost with sofZia ™ in patients with baseline TBUT less than 6 seconds.Results: Forty eyes of 20 consecutive patients using latanoprost with BAK were switched to travoprost with sofZia ™ . Mean TBUT prior to starting travoprost was 2.02 ± 0.71 seconds and increased to 6.34 ± 1.31 seconds 8 weeks after the switch (p Ͻ 0.001). Mean inferior corneal staining scores decreased from 2.40 ± 0.87 to 1.38 ± 0.59 (p Ͻ 0.001). Mean OSDI scores decreased from 26.31 ± 8.25 to 16.56 ± 6.19 (p Ͻ 0.001). Discussion: This report focuses on the status of the ocular surface, as documented by TBUT, corneal staining and OSDI, in patients switched from latanoprost with BAK to travoprost without BAK. The switch resulted in a statistically signifi cant increase in TBUT and decreases in corneal staining and OSDI in patients with low baseline TBUT values. Conclusion: BAK, a common preservative for glaucoma drops, may increase OSD by disrupting the tear fi lm and increasing conjunctival infl ammation. In this study, a change from a BAK-preserved prostaglandin analog (PGA) to a non-BAK-preserved PGA resulted in a measurable improvement of TBUT, corneal staining and OSDI. Further studies are needed to better understand the impact of BAK-preserved medications on the ocular surface.

The Cellular Basis for Biocide-Induced Fluorescein Hyperfluorescence in Mammalian Cell Culture

“…Corneal staining can be readily observed at the ocular surface after exposure to toxic agents. For example, Horsley and Kahook reported reduced corneal staining when patients were switched from glaucoma eye drops containing benzalkonium chloride (a common preservative in ocular medications) to a similar drug not containing this agent [1] . Topical anesthetic drops are also associated with corneal staining [2] .…”

Efficacy and safety of benzalkonium chloride-free fixed-dose combination of latanoprost and timolol in patients with open-angle glaucoma or ocular hypertension

“…BAK is an antimicrobial preservative commonly used in topical ophthalmic preparations that acts by disrupting microbial cell membranes and promoting cell death. 2 , 25 The use of BAK in ophthalmic solutions, however, has demonstrated a number of disadvantages in both in vitro and in vivo models, including dose-dependent and time-dependent toxicity to the corneal epithelium, the conjunctival epithelium, the stroma, and tear film constituents. 25 – 41 BAK may reduce epithelial cell integrity, impair healing, induce cytokine secretion, cause elevated production of conjunctival inflammatory cells, and reduce goblet cell numbers.…”

“… 2 , 25 The use of BAK in ophthalmic solutions, however, has demonstrated a number of disadvantages in both in vitro and in vivo models, including dose-dependent and time-dependent toxicity to the corneal epithelium, the conjunctival epithelium, the stroma, and tear film constituents. 25 – 41 BAK may reduce epithelial cell integrity, impair healing, induce cytokine secretion, cause elevated production of conjunctival inflammatory cells, and reduce goblet cell numbers. Further, BAK may impair tear function and reduce tear film integrity through its effects on the integrity of the meibomian layer and disruption of the lipid film continuous multilayer structure, thus decreasing tear film break-up time.…”

“… 42 These toxic side effects are important in the management of glaucoma because of cumulative BAK exposure associated with long-term use. 25 Patients may experience symptoms typical of ocular surface disease, such as dryness, burning or stinging, itching, irritation, tearing, photophobia, foreign body sensation, grittiness, redness, fatigue, varying visual acuity, blurred vision, and hyperemia. These symptoms can have a substantial impact on a patient’s quality of life and potentially lead to reduced adherence with treatment regimens.…”

In VitroEffects of Preservative-free and Preserved Prostaglandin Analogs on Primary Cultured Human Conjunctival Fibroblast Cells

“…New PG formulations without BAC or with alternative preservatives are currently in development. Several studies have revealed that alternative preservatives to BAC, for example sofZia (Alcon, Fort Worth, TX, USA), Purite (a stabilized oxychloro complex), and Polyquad, produce fewer corneal changes and less conjunctival inf lammation than BAC [ 1 - 3 , 14 , 15 ]. Preservative-free PGs are currently commercially available, and their low toxicity to the corneal and conjunctival surfaces has been confirmed [ 4 ].…”