Nasolacrimal duct probe

Also known as: Blocked tear duct probe, Lacrimal probe
Tears normally drain from the eye through small tubes called tear ducts that stretch from the eye into the nose. A blocked tear duct occurs when the duct that normally allows tears to drain from the eyes is obstructed or fails to open properly. If a tear duct remains blocked, the tear duct sac fills with fluid and may become swollen and inflamed, and sometimes infected.

Blocked tear ducts occur in about 6 out of 100 newborns. A blocked tear duct that is present at birth is called congenital nasolacrimal duct obstruction.

Probing is a procedure that is sometimes used to clear or open a blocked tear duct. The doctor inserts a surgical probe into the opening (punctum) of the tear duct to clear the blockage. Afterward, he or she may insert into the duct a tiny tube with water running through it. The water contains a fluorescein dye. If the doctor sees that dye has moved into the nasal cavity, he or she will know that probing worked. Often after probing, antibiotic eyedrops are used four times a day for one week.