Characteristics of tear meniscus, punctum, and cornea epithelium using an anterior segment optical coherence tomography in glaucoma

PurposeTo investigate the differences in punctal dimensions, tear meniscus height (TMH), and cornea epithelium among medically controlled glaucoma patients using anterior segment optical coherence tomography (AS-OCT) and evaluate the parameters that affect the results.MethodsThis cross-sectional, observational study included 80 subjects with primary open-angle glaucoma and 80 normal subjects without glaucoma and ocular symptoms. AS-OCT was used to measure TMH, outer punctal diameter (OPD), punctal depth (PD), and central corneal epithelial thickness (CCET). Correlations for the effect of topical anti-glaucoma medications on OPD, PD, TMH, and CCET were analyzed. The impact of prostaglandin analogs (PGAs) and Beta-blockers on the parameters were evaluated.ResultsNo significant differences were found in age and sex between the groups (<i>p</i> = 0.333 and <i>p</i> = 0.635, respectively). Glaucoma patients exhibited significantly narrower OPD (<i>p</i> < 0.001), TMH (<i>p</i> < 0.001), and CCET (<i>p</i> = 0.006). Subjects on longer-duration therapy showed a statistically significant reduction in TMH and CCET (<i>p</i> < 0.001 and <i>p</i> = 0.022). While the PD value was significantly lower in those using anti-glaucoma medications containing Beta-blockers (<i>p</i> = 0.002), the TMH value was significantly lower in those containing PGAs (<i>p</i> = <i>0.037</i>).ConclusionsTopical anti-glaucoma medications affect the OPD, TMH, and CCET in glaucoma patients compared with normal subjects. Topical anti-glaucoma medications usage duration has negative effects on TMH and CCET. Beta-blockers are more effective on the punctum, while PGAs are more effective on the TMH. These findings highlight the utility of AS-OCT in assessing asymptomatic glaucoma patients and its effects on the ocular surface.