Lacrimal sac

Lacrimal sac
Lacrimal sac
Gray896.png
The lacrimal apparatus. Right side. (Lacrimal sac visible at upper right.)
Gray894.png
The tarsi and their ligaments. Right eye; front view. (Lacrimal sac visible at middle right.)
Latin saccus lacrimalis
Gray's subject #227 1028
Artery angular artery

The lacrimal 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.

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

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.

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.

Additional images

  • Medial wall of left orbit.

  • Left orbicularis oculi, seen from behind.

See also

This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained within it may be outdated.

v · d · eHead and neck anatomy – accessory visual structures (TA 15.2.7, TH H3.11.08.6, GA 10.1021)
Eyelid

Tarsus (Meibomian pelicle) • Medial palpebral ligament • Epicanthic fold • Meibomian gland • Ciliary glands • Eyelash

Palpebral fissure • Canthus

Gland of Zeis
Lacrimal apparatus
Lacrimal lake • Lacrimal gland • Lacrimal canaliculi • Lacrimal punctum • Lacrimal papilla • Nasolacrimal duct • Lacrimal sac • Lacrimal caruncle • Krause's glands
Other

Periorbita • Orbital septum • Tenon's capsule • Suspensory ligament of eyeball

Eyebrow

Conjunctiva (Plica semilunaris)

Extraocular muscles (Trochlea of superior oblique)

M: EYE

anat(g/a/p)/phys/devp/prot

noco/cong/tumr, epon

proc, drug(S1A/1E/1F/1L)



Wikimedia Foundation. 2010.

Игры ⚽ Поможем написать курсовую

Look at other dictionaries:

  • lacrimal sac — sak n the dilated oval upper end of the nasolacrimal duct that is situated in a groove formed by the lacrimal bone and the frontal process of the maxilla, is closed at its upper end, and receives the lacrimal ducts * * * saccus lacrimalis …   Medical dictionary

  • lacrimal sac — noun either of the two dilated ends of the lacrimal ducts at the nasal ends of the eyes that fill with tears secreted by the lacrimal glands • Syn: ↑tear sac, ↑dacryocyst • Hypernyms: ↑vesicle, ↑cyst • Part Holonyms: ↑lacrimal apparatus …   Useful english dictionary

  • lacrimal sac — Anat. the dilated upper portion of the nasolacrimal duct that receives tears from the lacrimal ducts. [1770 80] * * * …   Universalium

  • lacrimal sac — noun The upper dilated end of the tear duct Syn: nasolacrimal sac …   Wiktionary

  • lacrimal apparatus — n the bodily parts which function in the production of tears including the lacrimal glands, lacrimal ducts, lacrimal sacs, nasolacrimal ducts, and lacrimal puncta * * * the structures that produce and drain away fluid from the eye. The lacrimal… …   Medical dictionary

  • lacrimal canaliculus — n LACRIMAL DUCT (1) * * * canaliculus lacrimalis [TA] the short passage in an eyelid, beginning at the punctum, that leads from the lacrimal lake to the lacrimal sac; called also lacrimal duct …   Medical dictionary

  • lacrimal duct — n 1) a short canal leading from a minute orifice on a small elevation at the medial angle of each eyelid to the lacrimal sac called also lacrimal canal, lacrimal canaliculus 2) any of several small ducts that carry tears from the lacrimal gland… …   Medical dictionary

  • sac — 1. A pouch or bursa. SYN: saccus [TA]. SEE ALSO: sacculus. 2. An encysted abscess at the root of a tooth. 3. The capsule of a tumor, or envelope of a cyst. [L. saccus, a …   Medical dictionary

  • Lacrimal canaliculi — Infobox Anatomy Name = PAGENAME Latin = canaliculus lacrimalis GraySubject = 227 GrayPage = 1028 Caption = The lacrimal apparatus. Right side. Caption2 = System = MeshName = MeshNumber = DorlandsPre = c 04 DorlandsSuf = 12208445 The lacrimal… …   Wikipedia

  • Lacrimal bone — Bone: Lacrimal bone Lacrimal bone visible near center …   Wikipedia

Share the article and excerpts

Direct link
… Do a right-click on the link above
and select “Copy Link”