A comparison of the success rates of endoscopic-assisted probing in the treatment of membranous congenital nasolacrimal duct obstruction between younger and older children and its correlation with the thickness of the membrane at the Valve of Hasner

Congenital nasolacrimal duct obstruction (CNLDO) remains the most common cause of epiphora in infants. This retrospective study compares the success rate of nasal endoscopic-assisted probing between younger (3 years and below) and older (above 3 years) children with membranous CNLDO and its correlation with the thickness of the membrane at the valve of Hasner. Case records of a total of 38 eyes in 34 children with membranous CNLDO who underwent endoscopic nasolacrimal duct probing and irrigation under general anesthesia were analyzed. The cases were divided into two groups, Group Y (20 cases of children 3 years and below) and Group O (18 cases of children above 3 years). The success of the procedure was defined as complete remission of symptoms and a clinical examination of eye to rule out the presence for discharge or watering after three months of the procedure. Overall, 35 cases (92.1%) were successfully treated with a success rate of 95% in Group Y and 88.9% in Group O. The mid-P exact test p value for the success rate between the two cohorts was not statistically significant (p = 0.59). The thick membrane was observed in 50% cases in Group Y and 33.33% cases in Group O (p = 0.34). There is no age related decline in the overall success rate for nasal endoscopic-assisted probing and irrigation in cases of membranous CNLDO. The thickness of the membrane may be a factor for failed blind probing, but it has no correlation with the success rate if probing is done under endoscopic guidance.