Aims: To find the cure rate of late (second year of age) and very late (3-5 years of age) initial probing for congenital nasolacrimal duct obstruction (CNLDO) and to identify the factors contributing to the failure rate of the probing in older children. Methods: In a prospective interventional case series study, 169 eyes of 125 consecutive patients (1-5 years old) with CNLDO underwent probing under general anaesthesia. Cure was defined as absence of tearing and discharge in the affected eye. Results: 138 eyes of 101 patients aged 13-60 months (mean 23.4 (SD 10.2)) were included. Of 15 eyes (10.8%) with complex CNLDO, 80% presented after 24 months of age (p<0.0001). The cure rate was 89% in patients 13-24 months of age and 72% after the age of 24 months (p = 0.01). It was 90.2% in the membranous and 33.3% in the complex CNLDO in both late and very late probing (p<0.0001). There was a high correlation (r = 0.97) and no significant difference between the cure rate at 1 week and final follow up. Conclusion: Accumulation of the complex CNLDO is the main risk factor for failure of probing in the older children. The outcome of the nasolacrimal duct probing at 1 week follow up is highly indicative of the final outcome. C ongenital nasolacrimal duct obstruction (CNLDO) is a common problem in the early years of life.1 Standard management in the first few months of life includes hydrostatic massage of the lacrimal sac and topical antibiotics. Where the condition persists beyond several months, early office probing 2 or hospital based probing around the age of 1 year 3 yields good result. Some authors reported that increasing age significantly decreased the success rate of probing beyond the age of 1 year.4-6 Therefore, some clinicians prefer to perform silicone intubation as the initial surgical procedure for older children (typically older than 18 months) with CNLDO.7 Some investigators, however, claimed that increasing age has no significant effect on the success rate of the probing in older children. [8][9][10][11] There are two hypotheses for the lower cure rate of probing in the older children with CNLDO. Whether this is because of prolonged inflammation and fibrosis in the lacrimal drainage system with increasing age 5 12 or the result of accumulation of complex obstruction with time as less severe obstruction clears spontaneously, 6 7 10 is not clear. There are few reports that specifically addressed the problem of complex CNLDO and its impact on probing of the older children. 13The aim of this study was to find the cure rate of the initial probing for CNLDO in children between 13 and 24 months (late) and 25 and 60 months (very late) of age and to assess the factors affecting the cure rate of late and very late initial probing for CNLDO. SUBJECTS AND METHODSIn a prospective non-comparative interventional case series, 169 eyes of 125 consecutive patients between the age of 1 and 5 years with CNLDO were probed in two university based hospitals from November 1999 to December 2001. Twenty four patients were excluded bec...

Ext-DCR is an effective and highly successful procedure for the treatment of NLDO regardless of the etiology.