Lacrimal sac

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Lacrimal sac
Sobo 1909 764.png
The lacrimal apparatusis shown through dissection on the left side.
Sobo 1909 765.png
The lacrimal sac has been opened showing internal organization as well as the naso-lacrymal duct.
Latin saccus lacrimalis
Gray's p.1028
Artery angular artery
Anatomical terminology

The lacrimal sac or lachrymal sac[1] is the upper dilated end of the nasolacrimal duct, and is lodged in a deep groove formed by the lacrimal bone and frontal process of the maxilla. It connects the lacrimal canaliculi, which drain tears from the eye's surface, and the nasolacrimal duct, which conveys this fluid into the nasal cavity.

Structure[edit]

It is oval in form and measures from 12 to 15 mm. in length; its upper end is closed and rounded; its lower is continued into the nasolacrimal duct.

Its superficial surface is covered by a fibrous expansion derived from the medial palpebral ligament, and its deep surface is crossed by the lacrimal part of the Orbicularis oculi, which is attached to the crest on the lacrimal bone.

Histology[edit]

Like the nasolacrimal duct, the sac is lined by stratified columnar epithelium with mucus-secreting goblet cells, with surrounding connective tissue. The Lacrimal Sac also drains the eye of any debris, bacteria, dirt, etc.

Function[edit]

This is mainly for high amounts of tears, in which the lacrimal sac pumps inward and outward driven by the orbicularis muscle during blinking.

Clinical significance[edit]

The lacrimal sac can be pictured by dacrocystography, which is injecting radiocontrast into it and performing X-ray imaging of it.

Additional images[edit]

See also[edit]

References[edit]

This article incorporates text from a public domain edition of Gray's Anatomy.

  1. ^ Dr. Johannes Sobotta (1909). Sobotta's Atlas and Textbook of Human Anatomy. Philadelphia.