lacrimal apparatus


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Related to lacrimal apparatus: Lacus lacrimalis

apparatus

 [ap″ah-rat´tus] (pl. appara´tus, apparatuses)
an arrangement of a number of parts acting together to perform a special function.
Golgi apparatus see golgi apparatus.
juxtaglomerular apparatus a collective term for the juxtaglomerular cells in a nephron.
lacrimal apparatus see lacrimal apparatus.
Wangensteen's apparatus a nasal suction apparatus connected with a duodenal tube for aspirating gas and fluid from stomach and intestine.

lacrimal

 [lak´rĭ-mal]
pertaining to tears.
lacrimal apparatus a group of organs concerned with the production and drainage of tears; it is a protective device that helps keep the eye moist and free of dust and other irritating particles. The lacrimal gland, which secretes tears, lies over the upper, outer corner of the eye; its excretory ducts branch downward toward the eyeball. A constant stream of tears washes down over the front of the eye and is drained off through two small openings located in the inner corner of the eye. Through these openings the tears pass into the lacrimal canaliculus, then through the lacrimal sac into the nasolacrimal duct and finally into the nasal cavity.
The lacrimal apparatus. From Jarvis, 1996.

lac·ri·mal ap·pa·ra·tus

[TA]
the structures that, with the conjunctival sac, produce and provide drainage for lacrimal fluid (tears), consisting of the lacrimal gland, the lacrimal lake, the lacrimal canaliculi, the lacrimal sac, and the nasolacrimal duct.
Synonym(s): apparatus lacrimalis [TA]

lac·ri·mal ap·pa·ra·tus

(lak'ri-măl ap'ă-rat'ŭs) [TA]
Consisting of the lacrimal gland, the lacrimal lake, the lacrimal canaliculi, the lacrimal sac, and the nasolacrimal duct.

lacrimal apparatus

Enlarge picture
LACRIMAL APPARATUS: Anterior view
Structures concerned with the secretion and conduction of tears. It includes the lacrimal gland and its secretory ducts, lacrimal canaliculi, lacrimal sac, and nasolacrimal duct, which empties into the nasal cavity. See: illustration

Patency of the lacrimal duct may be tested by placing a dilute solution of sugar in the conjunctival sac; if the duct is patent, the individual will report the sensation of sweetness in the mouth; if not, the sugar will not be perceived.

lacrimal apparatus

The system involved in the production and conduction of tears. It consists of the lacrimal gland and accessory lacrimal glands (glands of Krause and Wolfring); the eyelid margins; and the two puncta lacrimae. Each punctum is a small round or oval aperture situated on a slight elevation at the inner end of the upper and lower lid margin (lacrimal papilla) and forms the entrance to the canaliculi. Each canaliculus consists of a vertical portion of about

lacrimal apparatus

The system involved in the production and conduction of tears. It consists of the lacrimal gland and accessory lacrimal glands (glands of Krause and Wolfring); the eyelid margins; and the two puncta lacrimae. Each punctum is a small round or oval aperture situated on a slight elevation at the inner end of the upper and lower lid margin (lacrimal papilla) and forms the entrance to the canaliculi. Each canaliculus consists of a vertical portion of about 2 mm long and then bends inward for some 8 mm, the upper one being slightly shorter. The canaliculi pierce the lacrimal fascia (i.e. the periorbita covering the lacrimal sac or tear sac) and unite (forming the common canaliculus) to enter a small diverticulum of the sac called the sinus of Maier. The lacrimal sac is closed above and open below where it is continuous with the nasolacrimal duct which extends over some 1.5 cm in length to Hasner's valve (or Bianchi's valve or plica lacrimalis) (folds of mucous membrane) at the inferior meatus of the nose. The inferior opening of the duct is called the ostium lacrimale (Fig. L1). See dacryocystitis; epiphora; lacrimal fistula; fossa for the lacrimal sac; Sjögren's syndrome; tear duct; dye dilution test; Jones II test; valve of Krause.
Fig. L1 Lacrimal apparatusenlarge picture
Fig. L1 Lacrimal apparatus

lac·ri·mal ap·pa·ra·tus

(lak'ri-măl ap'ă-rat'ŭs) [TA]
Consisting of the lacrimal gland, the lacrimal lake, the lacrimal canaliculi, the lacrimal sac, and the nasolacrimal duct.
References in periodicals archive ?
Out of 514 patients, congenital lacrimal apparatus abnormalities were seen in 103(20%) children, with all but 2 having congenital nasolacrimal duct obstruction.
The present study on children with congenital eye anomalies showed that 98% of the congenital lacrimal apparatus abnormalities comprised of congenital nasolacrimal duct obstruction.
There appear to be only 2 previously reported cases of exogenous foreign bodies in the lacrimal apparatus. (2,3) Our patient had been experiencing epiphora, which had been attributed to a blockage within the nasolacrimal sac.
(12.) Khurana AK, Indu Khurana; Anatomy of lacrimal apparatus. Text Book of Anatomy and Physiology of eye:second Edition, pp 372- 378.
We excluded studies that included participants who had previous surgical procedures to the lacrimal apparatus.
A thorough ocular examination with particular reference to the lacrimal apparatus was done in all patients.
The lacrimal apparatus starts from the lacrimal gland and ends at the nasolacrimal duct.