Home > Encyclopedia of Medicine > Lacrimal Duct Obstruction

Definition

A lacrimal duct obstruction is blockage of the tear duct, the thin channel that normally drains tears from the surface of the eye.

Description

The lacrimal glands, located above each eyeball, produce tears. The tears flow over the eye, then drain through the nasolacrimal ducts. A tiny hole at the inner edge of each eyelid marks the opening of the ducts, which lead to the lacrimal sacs located on the side of the nose. The tears pass from the sacs into the nasolacrimal ducts and then into the nose.

When a tear duct becomes obstructed, tears may spill over the eyelids and run down the face. Stagnant tears within the system can become infected, leading to recurrent red eyes and infections. Excessive tearing can also produce secondary skin changes on the lower eyelids.

Causes and symptoms

An obstructed lacrimal tear duct can result in inflammation and infection of the lacrimal sac....