Evaluating Lacrimal Punctum Size as a Clinical Indicator of Dry Eye Disease Severity in a Real-World Lebanese Cohort

Background/Objectives: To investigate the relationship between lacrimal punctum size and the severity of dry eye disease (DED) in a clinically refractory, real-world patient cohort from a tertiary ophthalmology center in Lebanon. Methods: A retrospective observational study was conducted at Advanced Eye Care Center, Beirut, Lebanon (2016–2024). A total of 312 eyes from 156 patients with moderate-to-severe DED unresponsive to topical artificial tears, loteprednol etabonate, and cyclosporine (0.05% ophthalmic emulsion) were included. All eyes subsequently underwent lower lacrimal punctum plug insertion as part of clinical management. Lacrimal punctal diameter was estimated by the largest silicone plug (0.5 mm, 0.6 mm, or 0.7 mm) inserted nonforcefully into the lower punctum under slit-lamp visualization. Tear film stability was assessed by Tear Break-Up Time (TBUT). Group differences were analyzed using the Kruskal–Wallis H test with post hoc Mann–Whitney U tests (Bonferroni correction), and Spearman’s rank correlation was calculated to quantify the monotonic association. Results: Eyes were distributed across punctal diameter categories as follows: 0.5 mm (n = 15, 4.8%), 0.6 mm (n = 204, 65.4%), and 0.7 mm (n = 93, 29.8%). Median TBUT values were 5.55 s [IQR 5.51–5.77], 5.06 s [IQR 4.80–5.37], and 4.51 s [IQR 4.23–4.71] for the 0.5 mm, 0.6 mm, and 0.7 mm groups, respectively. Kruskal–Wallis analysis confirmed significant inter-group differences (H = 140.1, p < 0.001). All post hoc pairwise comparisons remained significant after Bonferroni correction (p < 0.001). Spearman’s rank correlation demonstrated a significant negative association between lacrimal punctal diameter and TBUT (ρ = −0.70, p < 0.000001). All analyses were conducted at the eye level and do not account for within-patient correlation (bilateral design, 156 patients); p-values should be interpreted accordingly. Conclusions: In this treatment-refractory cohort, larger lacrimal punctal diameter was significantly associated with greater tear film instability. These findings suggest that lacrimal punctal diameter estimation during therapeutic plug insertion may serve as a practical, cost-free adjunct to standard DED evaluation. Prospective multimodal studies are needed to validate punctal diameter as an independent clinical indicator of DED severity.