RESUMO
PURPOSE: The objective of this study was to analyze the impact of different factors on the success rate of probing for congenital nasolacrimal duct obstruction (CNLDO). METHODS: A retrospective analysis was conducted on 239 eyes of 202 patients who underwent probing for CNLDO between 2014 and 2019. Patients were divided into three age groups (12-24 months, 25-36 months, and over 36 months) and two groups based on the type of membranous obstruction (MO) and incomplete complex obstruction (ICO), with complete complex obstruction (CCO) cases being excluded. The study involved administering general anesthesia (GA) to all participants during the probing procedure. The patients were then monitored at scheduled intervals for up to 6 months after the surgery. Success was defined as an improvement in symptoms and signs, and logistic regression and Fisher's exact test were used for statistical analysis. RESULTS: The mean age of the patients was 25.48 ± 13.38 months, and the total success rate was 86.61%. The success rate for MO was 92.8%, 95.87%, and 97% in age groups 1, 2, and 3, respectively. The success rate for ICO was 91.17%, 80%, and 23.52% in age groups 1, 2, and 3, respectively. The success rate for MO was significantly higher than ICO in all age groups. The success rate for ICO was significantly lower in age group 3 (p = 0.009). CONCLUSION: The study found that probing performed within the first 36 months had high success rates regardless of age and type of obstruction. However, the success rate significantly decreased in patients undergoing probing for ICO at 36 months or later.