Nasolacrimal duct

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Nasolacrimal duct
The lacrimal apparatus. Right side.
Outline of bones of face, showing position of air sinuses.
Latin d. nasolacrimalis
Gray's subject #227 1029
MeSH Nasolacrimal+Duct
Dorlands/Elsevier d_29/12314970

The nasolacrimal duct (sometimes called tear ducts) carries tears from the lacrimal sac into the nasal cavity. Excess tears flow through nasolacrimal duct which opens in the nose. This is the reason the nose starts to run when a person is crying, or why you can sometimes taste eye drops.

Like the lacrimal sac, the duct is lined by stratified columnar epithelium containing mucus-secreting goblet cells, and is surrounded by connective tissue.

Obstruction of the nasolacrimal duct leads to the excess overflow of tears called epiphora. Persons with dry eye conditions can be fitted with punctal plugs that seal the ducts to limit the amount of fluid drainage and retain moisture.

The canal containing the nasolacrimal duct is called the nasolacrimal canal.

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