The tear drainage system has two parts. The first part consists of
two different types of glands that produce
tears. These tear glands are found:
- In the lining of the eyelids. These glands
(accessory lacrimal glands) start making tears at birth and constantly produce
small amounts of tears that wash the surface of the eyes and prevent
drying.
- In the bones that hold and protect the eyes (the orbits).
These glands (main lacrimal glands) produce larger amounts of tears when a
person cries or when something irritates the eyes, such as smoke. Usually, main
lacrimal glands start making tears at birth but may not produce tears until
several weeks later.
The second part of the system drains tears from the eyes into the
nose.
- When your eye blinks, the lids push the tears
across the eye into the drains (puncta) at the inner corner.
- The
drains empty into channels (canaliculi) that connect the eye with the nose. The
channels drain into tear sacs (lacrimal sacs) that lie beside the
nose.
- The sacs narrow into tear ducts (lacrimal ducts) that drain
through the nasal bone into the nostrils.
See an illustration of the
tear duct drainage system 
.
