Botulinum Toxin Injection Versus Conjunctivodacryocystorhinostomy for Epiphora Secondary to Proximal Lacrimal Obstruction: A Systematic Review and Meta-Analysis

To systematically evaluate the efficacy and safety of lacrimal gland botulinum toxin (BTX) injection and conjunctivodacryocystorhinostomy (CDCR) in proximal lacrimal system obstruction. PubMed, Web of Science, Scopus, and Cochrane CENTRAL were systematically searched through December 2025 for studies evaluating BTX injection or CDCR. Data on study characteristics, patient demographics, follow-up, efficacy outcomes including Munk score and Schirmer test, and adverse events were extracted. Pooled outcomes were estimated using random-effects models, with subgroup analyses and meta-regression performed to explore between-study heterogeneity. Twenty-one studies were included. These included four studies addressing BTX, sixteen addressing CDCR, and one study comparing between both BTX and CDCR. BTX was associated with significant improvement in epiphora symptoms (Munk score standardized mean difference [SMD], 1.64; 95% confidence interval [CI], 1.19–2.10) and reduced tear production (Schirmer test SMD: 0.74; 95% CI: 0.34–1.15), with no detected heterogeneity for either outcome (I2 = 0%). The pooled BTX success rate was 84% (95% CI: 76%–90%; I2 = 14.6%). Primary CDCR had a pooled success rate of 79% (95% CI: 62%–92%; I2 = 92.6%); whereas revision CDCR has a pooled success of 56%. Exploratory indirect subgroup comparison showed no statistically significant difference between BTX and primary CDCR estimates (p = .483). BTX-related adverse events were generally transient, whereas CDCR complications were mainly mechanical and device-related. Lacrimal gland BTX injection was associated with substantial symptomatic improvement, reduced tear production, and relatively consistent outcomes across studies. Primary CDCR also demonstrated favorable success rates but with considerable between study-heterogeneity and device-related morbidity. Current evidence does not establish equivalence or superiority between the two approaches. Modern retentive tubes may reduce malposition risk compared with classic designs.