Neha Patil

Lacrimal sac

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Artery  angular artery
Dorlands /Elsevier  s_01/12717293
FMA  20289
Latin  saccus lacrimalis
TA  A15.2.07.068
Lacrimal sac

The lacrimal sac or lachrymal sac 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.

Contents

Structure

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

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 debris and microbes.

Function

It serves as a reservoir for overflow of tears, in which the lacrimal sac pumps inward and outward driven by the orbicularis muscle during blinking.

Imaging

The lacrimal sac can be imaged by dacrocystography, in which radiocontrast is injected, followed by X-ray imaging.

References

Lacrimal sac Wikipedia


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