The Effect of Modified Probing (Lee's Swing Method) on Congenital Nasolacrimal Duct Obstruction

ABSTRACT

PURPOSE: To compare modified probing (swing method) to conventional probing for treating congenital nasolacrimal duct obstruction (CNLDO). METHODS: From March 1997 to February 2004, we compared the result between two groups of CNLDO patients one which underwent conventional probing (Group A 126 eyes of 126 patients) and the other which underwent modified probing (Group B 98 eyes of 98 patients) with the swing method. RESULTS: In the comparison between the two groups, there were no statistical differences in genders and ages. When we selected patients according to the age group, we found no differences in the primary success rate between Groups A and B (p=0.088 for the patients of aged six to twelve months old, p=0.051 for the patients aged 13 to 18 months old). Compared by the number of probings, patients with no history of probing in each group showed no significant difference in the success rate (p=0.301). On the other hand, the patients in Group B who experienced probing more than once showed a significantly higher success rate than those in Group A (p=0.033). CONCLUSIONS: We recommend the swing method as a primary treatment for CNLDO in preference to conventional probing because the swing method shows a higher success rate for patients older than 13 months and also for those with a history of previous probing.