Haversian Canal: From 1 Different Sources
one of the small canals (diameter about 50 ?m) that ramify throughout compact *bone. See also Haversian system. [C. Havers (1650–1702), English anatomist]
See GASTROINTESTINAL TRACT.... alimentary canal
The passage that extends from the neck of the womb (UTERUS), known as the CERVIX UTERI, to the opening of the VAGINA. The baby passes along this passage during childbirth.... birth canal
Canaliculus means a small channel, and is applied to (a) the minute passage leading from the lacrimal pore on each eyelid to the lacrimal sac on the side of the nose; (b) any one of the minute canals in bone.... canaliculus
The ?ne canals in BONE which carry the blood vessels, lymphatics and nerves necessary for the maintenance and repair of bone.... haversian canals
A structure in the inner ear that plays a role in balance. There are 3 semicircular canals in each ear, at right angles to each other, and connected via a chamber called the vestibule. The fluid-filled canals contain small hairs that detect movement and acceleration, and transmit information to the brain via the vestibular nerve.... semicircular canal
the terminal portion of the large intestine, which is surrounded by the muscles of defecation (anal sphincters). The canal ends on the surface at the anal orifice (see anus).... anal canal
(auditory meatus) the canal leading from the pinna to the eardrum.... auditory canal
n. a tubular channel or passage; e.g. the *alimentary canal and the auditory canal of the ear.... canal
n. inflammation of a canaliculus, especially a lacrimal canaliculus (see lacrimal apparatus).... canaliculitis
n. a particle derived from *otoliths in the *utricle of the inner ear, displaced from its normal site and located within the canal portion of one of the semicircular canals. Canaliths are implicated in *benign paroxysmal positional vertigo.... canalith
one of the cylindrical units of which compact *bone is made. A Haversian canal forms a central tube, around which are alternate layers of bone matrix (lamellae) and lacunae containing bone cells. The lacunae are linked by minute channels (canaliculi).... haversian system
a channel within the vitreous humour of the *eye. It extends from the centre of the optic disc, where it communicates with the lymph spaces of the optic nerve, to the posterior wall of the lens.... hyaloid canal
a bony canal in the *mandible on each side. It carries the inferior *dental nerve and vessels and for part of its length its outline is visible on a radiograph.... inferior dental canal
either of a pair of openings that connect the abdominal cavity with the scrotum in the male fetus. The inguinal canals provide a route for the descent of the testes into the scrotum, after which they normally become obliterated.... inguinal canal
see apicectomy.... retrograde root canal treatment
a channel in the eye, at the junction of the cornea and the sclera, through which the aqueous humour drains. [F. Schlemm (1795–1858), German anatomist]... schlemm’s canal
three tubes that form part of the membranous *labyrinth of the ear. They are concerned with balance and each canal registers movement in a different plane. At the base of each canal is a small swelling (an ampulla), which contains a *crista. When the head moves the fluid (endolymph) in the canals presses on the cristae, which register the movement and send nerve impulses to the brain.... semicircular canals
(SCDS) a rare condition characterized by sound- or pressure-induced vertigo (see Tullio phenomenon), hearing loss, *autophony, and a sense of fullness in the affected ear. It is associated with absence of the bone that normally lies over the superior *semicircular canal. Diagnosis involves computerized tomography and *vestibular evoked myogenic potential testing. Treatment involves surgery to repair the bony defect.... superior canal dehiscence syndrome
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