Definition of Blocked tear duct:

A blocked tear duct is a partial or complete blockage in the pathway that carries tears away from the surface of the eye into the nose.

Causes, incidence, and risk factors:

Tears are constantly being made to help protect the surface of your eye. They drain into a tear duct through a very small opening in the corner of your eye, near your nose. This opening is called the nasolacrimal duct. If this duct is blocked, the tears will build up and overflow onto the cheek, even when you are not crying.

In children, the duct may not be completely developed at birth. It may be closed or covered by a thin film, causing a partial blockage.

In adults, the duct can be damaged by infection, injury, or a tumor.