Lacrimal canaliculi

Lacrimal canaliculi

Infobox Anatomy
Latin = canaliculus lacrimalis
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Caption = The lacrimal apparatus. Right side.

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DorlandsPre = c_04
DorlandsSuf = 12208445

The lacrimal canaliculi, also known as the lacrimal canals or lacrimal ducts, are the small channels in each eyelid that commence at minute orifices, termed puncta lacrimalia, on the summits of the papillæ lacrimales, seen on the margins of the lids at the lateral extremity of the lacus lacrimalis.

* The "superior duct", the smaller and shorter of the two, at first ascends, and then bends at an acute angle, and passes medialward and downward to the lacrimal sac.

* The "inferior duct" at first descends, and then runs almost horizontally to the lacrimal sac.

At the angles they are dilated into ampullæ. Microscopically, they are lined by nonkeratinizing stratified squamous epithelium surrounded by fibrous tissue.

Outside the latter is a layer of striped muscle, continuous with the lacrimal part of the Orbicularis oculi; at the base of each lacrimal papilla the muscular fibers are circularly arranged and form a kind of sphincter.

Clinical significance

Canaliculitis is an inflammation of the canaliculus. [ [ Handbook of Ocular Disease Management - Molluscum Contagiosum ] ]

ee also

*Lacrimal apparatus


External links


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