Study of Surgical Procedures for Treatment of Persistent Nasolacrimal Duct Obstruction in Children < 4 Years Old

Balloon catheter nasolacrimal duct dilation consists of punctal dilation of at least one punctum and the passage into the nose of a semi-flexible wire probe with an inflatable balloon on the tip.

Nasolacrimal duct intubation consists of punctal dilation of at least one punctum with the passage of a flexible lacrimal probe into the nose and the placement of a temporary stent in the nasolacrimal duct.

Simple nasolacrimal duct probing consists of punctal dilation of at least one punctum and the passage of a probe into the nose.