We aimed to evaluate the safety and efficacy of office-based probing with dacryoendoscopy under local anesthesia for congenital nasolacrimal duct obstruction (CNLDO). This single-institution study retrospectively reviewed data on 72 eyes of 64 consecutive children (38 boys, 43 eyes; 26 girls, 29 eyes), aged between 6 and 17 (mean age: 10.0 ± 2.7) months with suspected CNLDO, from July 2016 to February 2022. These patients underwent probing with dacryoendoscopy under local anesthesia. CNLDO was diagnosed clinically based on the presence of epiphora and sticky eyes due to mucous discharge commencing within the first 3 months of life, increased tear meniscus height, and fluorescein dye disappearance test results. A total of 63 of the 72 eyes had narrowly defined CNLDO, and 9 eyes had other types of obstructions. The intervention success rate was 100% (63/63 eyes) for patients with typical CNLDO and 97.2% (70/72 eyes) for the entire study cohort. Moreover, CNLDO was classified into five types based on the features of the distal end of the nasolacrimal duct. Probing with dacryoendoscopy is safe and yields a high success rate in pediatric patients with CNLDO. This is the first study to assess the safety and efficacy of probing with dacryoendoscopy under local anesthesia in pediatric patients with CNLDO.

BACKGROUND: To report the success rates of office probing for congenital nasolacrimal duct obstruction (NLDO) among children of different age groups in Taiwan.
METHODS: In this single-center, retrospective study, 564 eyes of 477 patients under the age of 5 years diagnosed with congenital NLDO were treated in a stepwise manner between 2001 and 2013. For infants aged < 6 months, treatment with massage and observation was suggested, followed by deferred probing under topical anesthesia if symptoms persisted. However, in cases of severe infection, immediate probing was suggested. In children aged > 6 months, office probing was usually highly recommended. Those with probing failures received either a second probing or silicone intubation. Treatment success was defined as anatomic patency by immediate irrigation after probing and absence of epiphora or mucous discharge at the follow-up visit.
RESULTS: Primary probing was successful in 457 of 564 eyes (success rate: 81%). The success rate of primary probing was negatively correlated with increasing age: 90.1% (163/181), 79.6% (164/206), 76.8% (73/95), 73.5% (36/49), 75% (18/24), and 33% (3/9) for the age groups of 0 to <6 months, 6 to <12 months, 12 to <18 months, 18 to <24 months, 24 to <36 months, and 36-60 months, respectively (p < 0.001, Fisher\'s exact test). The second probing was successful in 52 of 81 eyes. In total, probing was successful in 509 of 564 eyes (success rate: 90.2%).
CONCLUSIONS: Office probing is safe and effective for treating congenital NLDO. The success rate of primary probing decreases significantly with age.

OBJECTIVE: To characterize the outcomes of initial and repeated office-based probing as a primary treatment for congenital nasolacrimal duct obstruction (CNLDO) in children.
METHODS: The medical records of patients who underwent nasolacrimal duct office-based probing for CNLDO between March 2004 and January 2008 were reviewed retrospectively. Nasolacrimal duct probing was performed on 244 eyes from 229 consecutive patients with CNLDO. Patients who were refractory to the first probing underwent a second probing 4 to 8 weeks later.
RESULTS: Based on exclusion criteria, 244 eyes from 229 patients (117 males and 112 females), aged 6 to 71 months (mean, 12.4 ± 8.36) were included. The success rate of the initial probing was 80% (196 of 244) for all patients, 82% (111 of 136) in the 6 to 12 month age group, 79% (64 of 81) in the 13 to 18 months age group, and 78% (21 of 27) among individuals older than 19 months (p = 0.868, Pearson chi-square test). The success rate of the second probing was 61% (25 of 41) for all patients, 74% (17 of 23) in the 6 to 12 months age group, 58% (7 of 12) in the 13 to 18 months age group, and 17% (1 of 6) among individuals older than 19 months (p = 0.043, Fisher\'s exact test).
CONCLUSIONS: While the success rate of initial nasolacrimal duct probing is not affected by age, the rate of success rate with a second probing was significantly lower in patients older than 19 months. Based on the results, authors recommend further surgical interventions, such as silicone tube intubation or balloon dacryocystoplasty, instead of repeated office probing for patients older than 19 months, if an initial office probing has failed.