Prevalence of buried probe in complex congenital nasolacrimal duct obstruction and evaluation of its success rate post 'probing and irrigation': a single-centre retrospective study.

Introduction: The aim of this study was to determine the prevalence of buried probe variant of complex congenital nasolacrimal duct obstruction (CNLDO) and to evaluate the outcome of probing and irrigation in such cases. Institutional review board approval was taken.

Material & Methods: A total of 309 eyes (258 patients) were diagnosed with CNLDO during the study period of January 2014-March 2017. A retrospective file review of 25 lacrimal systems of 20 patients diagnosed as buried probe variant of complex CNLDO was carried out during the study period.

Result: Buried probe variant of complex CNLDO was found to be 8% of the total CNLDO cases during the study period. Mean age at presentation was 1.7 years (range 8-48 months). Discharge and matting of eyelashes were the presenting symptoms in 22 out of 25 (88%) cases, whereas the only epiphora was the presenting symptom in three (12%) cases. Regurgitation of mucopurulent discharge on pressure over lacrimal sac area was positive in 16 out of 25 (64%) eyes. Associated lacrimal and nasal pathologies were seen in six out of 25 cases (24%). Success rate in buried probe variant cases of CNLDO in our study at 3-month follow-up was 88% (22 of 25 cases).

Conclusion: A high period prevalence of 8% out of all CNLDO cases in our study suggests that the buried probe should be considered in selective cases of CNLDO and earlier unsuccessful probing.