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Related to anal canal: hemorrhoids, appendix, Ischioanal fossa
a relatively narrow tubular passage or channel.
adductor canal Hunter's canal.
Alcock's canal a tunnel formed by a splitting of the obturator fascia, which encloses the pudendal vessels and nerve.
alimentary canal see alimentary canal.
anal canal the terminal portion of the alimentary canal, from the rectum to the anus.
atrioventricular canal the common canal connecting the primordial atrium and ventricle; it sometimes persists as a congenital anomaly.
birth canal the canal through which the fetus passes in birth.
carotid canal one in the pars petrosa of the temporal bone, transmitting the internal carotid artery to the cranial cavity.
cervical canal the part of the uterine cavity lying within the cervix.
condylar canal an occasional opening in the condylar fossa for transmission of the transverse sinus; called also posterior condyloid foramen.
canal of Corti a space between the outer and inner rods of Corti.
femoral canal the cone-shaped medial part of the femoral sheath lateral to the base of Gimbernat's ligament.
haversian canal any of the anastomosing channels of the haversian system in compact bone, containing blood and lymph vessels, and nerves.
Hunter's canal a fascial tunnel in the middle third of the medial part of the thigh, containing the femoral vessels and saphenous nerve. Called also adductor canal.
hypoglossal canal an opening in the occipital bone, transmitting the hypoglossal nerve and a branch of the posterior meningeal artery; called also anterior condyloid foramen.
infraorbital canal a small canal running obliquely through the floor of the orbit, transmitting the infraorbital vessels and nerve.
inguinal canal the oblique passage in the lower anterior abdominal wall on either side, through which passes the round ligament of the uterus in the female, and the spermatic cord in the male.
optic canal a passage for the optic nerve and ophthalmic artery at the apex of the orbit; called also optic foramen.
pulp canal root canal.
root canal that part of the pulp cavity extending from the pulp chamber to the apical foramen. Called also pulp canal.
sacral canal the continuation of the spinal canal through the sacrum.
Schlemm's canal venous sinus of sclera.
semicircular c's see semicircular canals.
spinal canal (vertebral canal) the canal formed by the series of vertebral foramina together, enclosing the spinal cord and meninges.
Volkmann's c's canals communicating with the haversian canals, for passage of blood vessels through bone.
terminal portion of the alimentary canal; about 4 cm long, beginning at the anorectal junction, where the rectal ampulla abruptly narrows as the alimentary canal pierces the pelvic diaphragm (levator ani), and ending at the anal verge, when the anoderm that lines the lower anal canal changes to hairy perianal skin; surrounded by the internal and external anal sphincters.
Synonym(s): canalis analis [TA]
the final portion of the digestive tract, about 4 cm long, between the rectum and the anus.
a·nal ca·nal(ā'năl kă-nal') [TA]
The terminal portion of the alimentary canal; it extends from the pelvic diaphragm to the anal orifice.
Synonym(s): canalis analis [TA] .
Synonym(s): canalis analis [TA] .
The 4 cm long terminal section of the large intestine, beginning where the rectum passes downward and forward through the pelvic diaphragm and ending in the anus. The entire length of the anal canal is surrounded by sphincter muscles, and the canal remains closed except during defecation and passage of flatus.See: illustration
See also: canal
anal canalThe 5 cm-long terminal portion of the intestine that lies immediately below the RECTUM. The anal canal contains two muscular rings (SPHINCTERS) that can close it tightly and seven or more longitudinal pads of MUCOUS MEMBRANE that contain veins and press together to act as an additional sealing mechanism.
relating to the anus.
acute, purulent infections in the area of the anus, usually caused by gram-negative organisms. In dogs, these most often arise from the anal sacs.
anal atresia, atresia ani
congenital absence or stenosis of the anus manifested by an absence of feces and a gradual development of abdominal distention. Fistulae may develop between the rectum and urogenital tract. The anomalous development can occur in several forms and may be accompanied by similar atresia at higher levels of the intestine. There is usually normal development of sphincters. A dimple is usually evident at the point at which surgical intervention is required.
the short, terminal, retroperitoneal segment of the intestinal tract between the rectum and anus.
a congenital constriction combined with vulvar constriction occurs in Jersey cattle.
occurs in cattle and excision effected for esthetic reasons.
see perianal fistula.
see anal fold.
see perianal fistula.
the dorsal part of the cloacal membrane in the embryo; when it eventually breaks down the dorsal passage becomes the rectoanal passage.
see rectovaginal fistula.
the protrusion of a small amount of mucosa through the anus.
the pursing of the anal orifice when the perineum is stimulated; indicative of an animal with intact sacral segments of the spinal cord.
see anal sacs.
inflammation of the anal sacs.
the internal anal sphincter is formed from smooth muscle of the anal canal while the external anal sphincter, which is larger and of greater importance in fecal continence, consists of striated muscle.
anal sphincter hypertrophy
occurs in aged dogs and may give rise to difficult and painful defecation.
scar formation after perianal fistulae, trauma, severe anal sac disease, or treatment for neoplasia may result in a reduced lumen and particularly a loss of the capacity to dilate with passage of feces. Straining, passage of ribbon-like feces and constipation result.
inflammation and ulceration of the perianal skin which may be associated with anal sac disease. Seen most commonly in German shepherd dogs.
a relatively narrow tubular passage or channel.
see lateral canal (below).
in the body of the basisphenoid bone, transmits the maxillary artery.
the digestive tube from mouth to anus. See also alimentary canal.
the terminal portion of the alimentary canal, from the rectum to the anus.
the common canal connecting the primitive atrium and ventricle; it sometimes persists as a congenital anomaly.
the canal through which the fetus passes in birth.
one in the pars petrosa of the temporal bone, transmitting the internal carotid artery to the cranial cavity.
on the palmar surface of the equine carpus where the carpal groove is converted into a canal by the flexor retinaculum which stretches from the accessory carpal bone to the medial side of the carpus. It houses the flexor tendons.
central brain canal
lumen of the neural tube of the embryo within the brain.
the part of the uterine cavity lying within the cervix.
in the occipital bone; transmits a vein.
canal of Corti
a space between the outer and inner rods of Corti.
external ear canal
the canal from the external auditory meatus to the eardrum.
osseous tube in the temporal bone that transmits the facial nerve.
in the groin on the medial aspect of the thigh; contains the femoral artery and vein.
c's of Gartner
in the ventral wall of the vagina; they are remnants of the mesonephric ducts and very variable in their occurrence. Called also ductus epoophori longitudinales.
see haversian canal.
c's of Hering
openings between the bile canaliculi and the cholangioles, the terminal ducts of the biliary duct system. Called also cholangiole.
central canal of the vitreous humor running from the lens to the optic disk.
an opening in the occipital bone, transmitting the hypoglossal nerve and a branch of the posterior meningeal artery; called also anterior condyloid foramen.
a canal running obliquely from the front of the orbit to the side of the muzzle, transmitting the infraorbital vessels and nerve. In the horse it passes through the maxillary sinus.
the oblique passage in the caudal abdominal wall on either side, through which passes the round ligament of the uterus in some females such as the bitch and the spermatic cord in the males.
small and large intestines.
the nasolacrimal canal.
a small canal in the root of a tooth which emerges on the side, rather than the apex. Called also accessory canal.
a passageway within the mandible for conduction of the inferior alveolar vessels and nerve; the inferior alveolar nerve enters the mandibular canal through the mandibular foramen and exits at the mental foramen supplying nerves to the lower cheek teeth in passing.
1. vertebral canal.
2. the cavity, containing marrow, in the diaphysis of a long bone; called also marrow or medullary cavity.
formed by the metatarsal fascia on the plantar aspect of the chief metatarsal bone of the horse; transmits the tendons of the digital flexor muscles.
in the cochlea of the internal ear; it transmits blood vessels and nerves to the cochlea.
in the maxilla it transmits the nasolacrimal duct.
large vascular canals through the cortex of bones. See also haversian canal.
the direct passage through the omasum from the reticulum to the abomasum.
a passage for the optic nerve through the cranium into the orbit.
formed by the maxilla and the palatine bone; transmits the palatine artery and nerve.
in the basisphenoid bone; contains the pterygoid nerve.
see root canal.
the part of the vertebral canal through the sacrum.
the venous sinus of the sclera, a circular canal at the junction of the sclera and cornea that receives the aqueous humour. Called also scleral venous sinus.
the canals (anterior, lateral and posterior) of the bony labyrinth of the ear. See also semicircular canals.
spinal canal, vertebral canal
the canal formed by the series of vertebral foramina together, enclosing the spinal cord and meninges.
in the frontal bone; transmits the frontal vein, passing through the zygomatic process to the orbital cavity.
formed by the plantar annular ligament of the tarsus which roofs over the tarsal groove; transmits the deep digital flexor tendon and plantar vessels.
the foramen at the junction of the coracoid, clavicle and scapula which transmits the tendon of a flight muscle, the supracoracoideus, in the avian skeleton.
canals communicating with the haversian canals, for passage of blood vessels through bone from the periosteum.