The Prevalence of Ocular Surface Disease in Glaucoma Patients

Abstract

Introduction: Glaucoma is the third cause of blindness in developed countries after age-related macular degeneration (AMD) and diabetic retinopathy. The aim of this study was to determine the prevalence of ocular surface disease in patients treated for glaucoma or ocular hypertonia. Patients and methods: We conducted a one-year observational study including glaucoma patients older than 15 years, diagnosed and treated for more than six months. The impact of anti-glaucoma treatment on the ocular surface was assessed by a questionnaire derived from the Ocular Surface Disease Index (OSDI). Results: Antiglaucoma treatment caused an alteration of the ocular surface in 59% of patients. 61.7% of patients had a mean epithelial thickness below normal. Discussion: Several observational studies have shown a high prevalence of ocular surface disease in glaucoma patients. The prevalence of surface involvement in our study is close to most studies in the literature. The strong correlation between the number of eye drops prescribed and the severity of ocular surface involvement has been proven. This correlation is attributed to the preservative benzalkonium chloride (BAK). Among the cellular alterations, we noted a decrease in mucus cells with a decrease and instability of the thickness of the tear film, which was more important in patients under BAK preserved eye drops than in those without BAK. Conclusion: Our study allowed us to determine the frequency of ocular surface damage in patients treated long-term with hypotonizing eye drops. The mechanisms of this damage are multiple. Preservatives seem to play a central role in the genesis of these reactions.