To determine the success rate of probing for the treatment of congenital nasolacrimal duct obstruction and to identify the clinical factors affecting the success rates.

The records of probing procedures from January 2005 to January 2015 were reviewed. The present study included 200 eyes of 174 patients with congenital nasolacrimal duct obstruction. Successful probing was defined as complete resolution of epiphora 3 months after treatment. Success rates were compared between the 2 groups in terms of sex, age, laterality, and previous probing.

A total of 200 eyes of 174 children (109 eyes of 94 males and 91 eyes of 80 females; mean age, 7.51 ± 3.39 months) had undergone the probing procedure. The overall success rates of primary probing were 81.5%, with an 80.7% success rate in males (88 eyes of 109 eyes) and 82.5% in females (75 eyes of 91 eyes). Success rates were 83.5% for the 91 eyes in children aged 0 to 6 months, 80.0% for the 90 eyes in children 6 to 12 months, and 78.9% for the 19 eyes in children over 12 months. No statistical significances were found among age groups. The probability of treatment success was lower in bilateral disease ( p < 0.05; 86.4-67.3%). Twenty-four of 37 eyes with unsuccessful primary probing underwent secondary probing, resulting in a 70.8% success rate. Silicone tube insertion was performed in 4 eyes repeatedly, however, the procedures were unsuccessful. The overall success rate was 90%.

The success rates among various age groups were not statistically significant. The probability of treatment success was lower in bilateral cases. Probing is an effective first-line treatment in children diagnosed with nasolacrimal duct obstruction. Close observation and appropriate treatment should be considered in patients with bilateral disease.