BACKGROUND: Although nasolacrimal duct probing is the standard treatment for congenital nasolacrimal duct obstruction (CNLDO) among children, the optimal timing of this procedure has been a topic of debate. The aim of the study was to analyze the clinical efficacy of nasolacrimal duct probing among patients with CNLDO symptoms at various ages.
METHODS: An 8-year retrospective study involved 2434 patients (3009 eyes), who underwent nasolacrimal duct probing conducted under topical anesthesia in the operating theatre. The study group consisted of 1148 girls (47.2%) and 1286 boys (52.8%) from 2 weeks to 41 months (average age was 8 ± 5.6 months). The participants were divided into nine age groups: 0-2 months, 3-6 months, 7-9 months, 10-12 months, 13-15 months, 16-18 months, 19-21 months, 22-24 months and over 24 months.
RESULTS: Bilateral obstruction was present among 575 (23.6%) children and was associated with a higher percentage of unsuccessful procedures compared to patients with unilateral obstruction (16.9% vs 10.2%, p < 0.001 Chi-square test). The success rate of the initial probing was 87.2% for all children and it was shown that it decreased with age. In the above age groups, it was 87.9%; 91.4%; 89.6%; 86%; 76.3%; 71.3%; 70.3%; 70.2%; 65.4%, respectively.
CONCLUSIONS: Probing is a safe and effective procedure. However, age at the time of the initial intervention and bilateral surgery constitute significant risk factors for failed probing. Probing between 7 and 9 months appears to be reasonable treatment strategy for children without recurrent infections. Early surgical intervention may be considered for patients with additional signs.

BACKGROUND: Pediatric nasolacrimal duct obstruction (PNDO) requires therapeutic intervention after conservative procedures failed. As resilient treatment guidelines for the treatment are missing, the aim of this study was to evaluate the advantages of two different intervention techniques in children with PNDO.
METHODS: Between January, 2006 and June, 2014, 233 children (0-208 months) were treated either with conventional probing by ophthalmologists only (Group I) or with endonasal endoscopic interdisciplinary approach (Group II). The clinical outcome was analyzed.
RESULTS: The overall success rate of Group I was 93.4% compared to 98.4% of Group II (P<0.05). 50% of all interventions (n=62) of Group II required further surgical procedures in addition to probing/irrigation, particularly with regard to children <6 and >24 months.
CONCLUSIONS: Endoscopic control in treatment of PNDO allows exact identification of the stenosis and appropriate surgical intervention with an improved clinical outcome. Endonasal endoscopic surgical techniques should be the standard PNDO treatment.

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.