Khatib L, et al. - This trial encompassed the inspection of the Masterka stent as a primary treatment in complex forms of nasolacrimal duct obstruction (NLDO), with the inclusion of bony ductal stenosis and proximal and serial membranous obstruction. This stent could be beneficial in a younger subset of patients with more complex forms of congenital NLDO. There existed a lower success rate among children >2 years of age and complex forms of NLDO, and particularly among those with bony stenosis.