lacrimal apparatus

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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]

lacrimal apparatus

a network of structures of the eye that secrete tears and drain them from the surface of the eyeball. These parts include the lacrimal glands, lacrimal ducts, lacrimal canals, lacrimal sacs, and nasolacrimal ducts.
enlarge picture
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.

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.

lacrimal apparatus

(lak´rəməl),
n a network of structures of the eye that secrete tears and drain them from the surface of the eyeball. The parts include the lacrimal glands, the lacrimal ducts, the lacrimal sacs, and the nasolacrimal ducts.

apparatus

1. an arrangement of a number of parts acting together to perform a special function.
2. certain organ systems such as respiratory or digestive apparatus.

apparatus digestorius
see digestive system.
fetlock joint suspensory apparatus
see suspensory ligament.
forelimb stay apparatus
an apparatus of ligaments and tendons which prevents the forelimb from buckling while the horse is standing for long periods of time; includes mechanisms to prevent flexion of the shoulder and elbow joints, and to prevent overextension or flexion of the carpal joint.
hindlimb stay apparatus
an apparatus of ligaments and tendons which prevents the hindlimb from buckling while the horse is standing for long periods of time; includes mechanisms to lock the stifle and hock joints including the presence of a 'reciprocal apparatus', which ensures that the two joints perform in unison.
lacrimal apparatus
the structures associated with the production, flow and drainage of tears; it includes the lacrimal and accessory glands and their excretory ducts, the lacrimal canals, the lacrimal sac and the nasolacrimal duct.
reciprocal apparatus
consists of two tendinous cords in the hindlimb of the horse, the peroneus tertius and the superficial flexor, which connect the distal end of the femur to the hock, one on the cranial face of the tibia, the other on the caudal face; they ensure that the two joints always move in unison.
Wangensteen's apparatus
a nasal suction apparatus connected with a duodenal tube for aspirating gas and fluid from the stomach and intestine.

lacrimal

pertaining to tears.

lacrimal apparatus
a group of organs concerned with the production and drainage of tears; it is a nutritive and protective device that helps keep the eye moist and free of dust and other irritating particles. Includes lacrimal gland, accessory lacrimal glands, third eyelid glands and the nasolacrimal duct.
Enlarge picture
Nasolacrimal apparatus in the dog.By permission from McCurnin D, Poffenbarger EM, Small Animal Physical Diagnosis and Clinical Procedures, Saunders, 1991
lacrimal canaliculus
the lacrimal duct within the eyelid.
lacrimal caruncle
the rounded, often pigmented swelling at the medial canthus of the eye.
lacrimal cyst
congenital displacement of lacrimal tissue results in subconjunctival cysts.
lacrimal drainage system
the structures concerned with tear collection; includes lacrimal lake, puncta, canaliculi, sac and nasolacrimal duct.
lacrimal duct
there are two of these minute ducts draining tears from the conjunctiva, via the lacrimal puncta, into the lacrimal sac. Called also lacrimal canaliculus.
lacrimal duct irrigator
a 20 gauge, blunt-pointed, straight or curved cannula with a needle attachment so that it can be attached directly to a syringe nozzle.
lacrimal fossa
fossa in the medial wall of the orbital rim which houses the lacrimal sac.
lacrimal gland
contained in a pad of fat in the dorsolateral part of the orbital cavity and drains into the conjunctival sac via many excretory ducts. The secretion is largely watery tears, but in the pig is mucus. May develop adenitis.
lacrimal gland anomalies
failure of patency of the duct, supernumerary opening of the duct and ductal ectasia recorded.
lacrimal gland atrophy
part of the syndrome of keratoconjunctivitis sicca.
imperforate lacrimal puncta
see imperforate punctum.
lacrimal lake
the recess between the lids at the nasal commissure of the eye where the tears collect.
lacrimal pump
contraction of the orbiculari oculi muscle creates pressure on the lacrimal sac which causes tears to drain from the lacrimal lake.
lacrimal punctum
there is one on each eyelid close to the medial canthus. Each drains tears from the conjunctival sac into the lacrimal duct in the same eyelid. The tears then pass to the lacrimal sac and into the nasolacrimal duct. See also punctum.
lacrimal reflex
tear production caused by irritation of the cornea and conjunctiva.
lacrimal sac
the distended proximal end of the nasolacrimal duct into which the lacrimal ducts empty.
lacrimal sinus
an excavation of the lacrimal bone which communicates with the maxillary sinus in some species.
lacrimal system
see lacrimal apparatus (above).