Alimentary canal Health Dictionary

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

A long canal, the digestive tract, from the mouth to the anus, through which food passes in the process of digestion and absorption. ... alimentary tract

A dental procedure performed to save a tooth in which the pulp (see pulp, dental) has died or become untreatably diseased, usually as the result of extensive dental caries.

The pulp is removed through a hole drilled in the crown. An antibiotic paste and a temporary filling are packed in. A few days later, the filling is removed and the canals are checked for infection. When no infection is detected the cavity is filled and the roots are sealed with cement. If the cavity is not filled completely, periodontitis may occur.

Treated teeth may turn grey but their appearance can be restored by bonding (see bonding, dental), fitting an artificial crown (see crown, dental), or by bleaching (see bleaching, dental).... root-canal treatment

The ?ne canals in BONE which carry the blood vessels, lymphatics and nerves necessary for the maintenance and repair of bone.... haversian canals

Surgery to relieve pressure on the spinal cord or a nerve root emerging from it (see microdiscectomy). Pressure may have various causes, including a disc prolapse, a tumour or abscess of the spinal cord, or a tumour, abscess or fracture of the vertebrae. Any of these conditions can cause weakness or paralysis of the limbs and loss of bladder control.

To treat major disc prolapses and tumours, a laminectomy (removal of the bony arches of 1 or more vertebrae) to expose the affected part of the cord or nerve roots may be performed. Recovery after treatment depends on the severity and duration of the pressure, the success of the surgery in relieving the pressure, and whether any damage is sustained by the nerves during the operation.... decompression, spinal canal

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 small canals (diameter about 50 ?m) that ramify throughout compact *bone. See also Haversian system. [C. Havers (1650–1702), English anatomist]... haversian canal

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