- accessory c. a channel leading from the root pulp laterally through the dentin to the periodontal tissue; may be found anywhere in the tooth root, but is more common in the apical third of the root. SYN: lateral c..
- adductor c. [TA] the space in middle third of the thigh between the vastus medialis and adductor muscles, converted into a c. by the overlying sartorius muscle. It gives passage to the femoral vessels and saphenous nerve, ending at the adductor hiatus. SYN: canalis adductorius [TA], Hunter c., subsartorial c..
- alimentary c. SYN: digestive tract.
- alveolar canals of maxilla [TA] canals in the body of the maxilla that transmit nerves and vessels from the alveolar foramina to the maxillary teeth. SYN: canales alveolares corporis maxillae [TA], alveolodental canals, dental canals.
- anal c. [TA] terminal portion of the alimentary c.; about 4 cm in length, beginning at the anorectal junction, where the rectal ampulla rather abruptly narrows as the alimentary c. pierces the pelvic diaphragm (levator ani), and ending at the anal verge, when the anoderm that lines the lower anal c. changes to hairy perianal skin; surrounded by the internal and external anal sphincters. SYN: canalis analis [TA].
- archenteric c. invagination of the blastopore into the notochordal process to form a cavity. See neurenteric c.. SYN: notochordal c..
- arterial c. SYN: ductus arteriosus.
- atrioventricular c. the c. in the embryonic heart leading from the common sinuatrial chamber to the ventricle.
- basipharyngeal c. SYN: vomerovaginal c..
- Bichat c. SYN: quadrigeminal cistern.
- Böttcher c. SYN: utriculosaccular duct.
- Breschet canals SYN: diploic canals.
- carotid c. [TA] a passage through the petrous part of the temporal bone from its inferior surface upward, medially, and forward to the apex where it opens posterior and superior to the site of the foramen lacerum. It transmits the internal carotid artery and plexuses of veins and autonomic nerves. SYN: canalis caroticus [TA].
- central c. [TA] SYN: canalis centralis medullae spinalis [TA], syringocele (1), tubus medullaris. SYN: central c. of spinal cord.
- central c. of spinal cord [TA] the ependyma-lined lumen (cavity) of the neural tube, the cerebral part of which remains patent to form the ventricles of the brain, while the spinal part in the adult often is reduced to a solid strand of modified ependyma. SYN: central c. [TA].
- cervical c. [TA] a fusiform c. extending from the isthmus of the uterus to the opening of the uterus into the vagina. SYN: canalis cervicis uteri [TA].
- cervicoaxillary c. superior opening to the axilla, bounded by clavicle anteriorly, scapula posteriorly and first rib medically. Axillary vessels and brachial plexus are transmitted.
- condylar c. [TA] the inconstant opening through the occipital bone posterior to the condyle on each side that transmits the occipital emissary vein. SYN: canalis condylaris [TA], condyloid c., posterior condyloid foramen.
- Cotunnius c. SYN: vestibular aqueduct.
- craniopharyngeal c. SYN: pituitary diverticulum.
- deferent c. SYN: ductus deferens.
- dentinal canals SYN: canaliculi dentales, under canaliculus.
- diploic canals [TA] channels in the diploë that accommodate the diploic veins. SYN: canales diploici [TA], Breschet canals.
- Dorello c. a bony c. sometimes found at the tip of the temporal bone enclosing the abducens nerve and inferior petrosal sinus as these two structures enter the cavernous sinus.
- endodermal c. SYN: primitive gut.
- endometrial c. [TA]
- facial c. [TA] the bony passage in the temporal bone through which the facial nerve passes; the facial c. commences at the internal auditory meatus with the horizontal part which passes at first anteriorly (medial crus of facial c.) then turns posteriorly at the geniculum of the facial c. to pass medial to the tympanic cavity (lateral crus of facial c.); finally, it turns downward (descending part of facial c.) to reach the stylomastoid foramen. SYN: canalis nervi facialis [TA], aqueductus fallopii, fallopian aqueduct, fallopian c..
- femoral c. [TA] the medial compartment of the femoral sheath, which is often occupied by the intermediate deep inguinal lymph node (of Cloquet), and provides both passage for lymphatics passing from lower limb to trunk and facilitates expansion of the adjacent femoral vein, as when it enlarges during a Valsalva maneuver. SYN: canalis femoralis [TA].
- galactophorous canals SYN: lactiferous ducts, under duct.
- Gartner c. SYN: longitudinal duct of epoöphoron.
- gastric c. [TA] furrow formed temporarily between longitudinal rugae of the gastric mucosa along the lesser curvature during swallowing; observed radiographically and endoscopically, it is formed because of the firm attachment of the gastric mucosa to the muscular layer, which is devoid of an oblique layer at this site; said to form a passageway favored by saliva and small quantities of masticated food and other fluids as they flow from cardia to gastroduodenal junction. SYN: canalis gastricus [TA], magenstrasse.
- greater palatine c. [TA] the canalis formed between the maxilla and palatine bones; it transmits the descending palatine artery and the greater palatine nerve. SYN: canalis palatinus major [TA], pterygopalatine c..
- gubernacular c. a small c. located between the permanent tooth germ and the apex of the deciduous tooth, containing remnants of dental lamina and connective tissue.
- c. of Guyon passageway through the transverse carpal ligament by which the ulnar nerve and artery enter the palm; it is closely related to the pisiform and the hook of the hamate.
- Guyon c. the superficial c. between the flexor retinaculum of the hand and flexor carpi ulnaris through which pass the ulnar nerve and vasculature between forearm and hand.
- gynecophoric c. a ventral groove running the length of male schistosome flukes, into which the threadlike female worm fits.
- haversian canals vascular canals that run longitudinally in the center of haversian systems of compact osseous tissue. SYN: Leeuwenhoek canals.
- Hensen c. SYN: ductus reuniens.
- c. of Hering SYN: cholangiole.
- Hirschfeld canals SYN: interdental canals.
- c. of Hovius an anastomotic circle between the anterior twigs of the venae vorticosae in the eyes of some animals, but not in normal human eyes.
- hyaloid c. [TA] a minute c. running through the vitreous from the optic disk to the lens, containing in fetal life a prolongation of the central artery of the retina, the hyaloid artery. See vitreous, hyaloid artery. SYN: canalis hyaloideus [TA], central c. of the vitreous, Cloquet c., Stilling c..
- hypoglossal c. [TA] the c. through which the hypoglossal nerve emerges from the skull. SYN: canalis hypoglossalis [TA], anterior condyloid c. of occipital bone, anterior condyloid foramen.
- incisive canals [TA] several bony canals leading from the floor of the nasal cavity into the incisive fossa on the palatal surface of the maxilla; they convey the nasopalatine nerves and branches of the greater palatine arteries that anastomose with the septal branch of the sphenopalatine artery. SYN: canales incisivi [TA], incisor canals.
- infraorbital c. [TA] a c. running beneath the orbital margin of the maxilla from the infraorbital groove, in the floor of the orbit, to the infraorbital foramen; it transmits the infraorbital artery and nerve. SYN: canalis infraorbitalis [TA].
- inguinal c. [TA] the obliquely directed passage through the musculoaponeurotic layers of the lower abdominal wall that transmits the spermatic cord in the male and the round ligament in the female from the pelvic cavity to the scrotum or labia majora, respectively. SYN: canalis inguinalis [TA], abdominal c., Velpeau c..
- interdental canals canals that extend vertically through alveolar bone between roots of mandibular and maxillary incisor and maxillary bicuspid teeth. SYN: Hirschfeld canals.
- interfacial canals intercellular spaces occurring in relation to intercellular attachments by desmosomes in stratified squamous epithelium, generally resulting from shrinkage of an artifact of fixation.
- Kürsteiner canals a fetal complex of vesicular, canalicular, and glandlike structures derived from parathyroid, thymus, or thymic cord; they are rudimentary and functionless unless persistent postnatally, when they may occur as cystic structures in the vicinity of parathyroid III and thymus III. Kürsteiner described three types, type II canals being associated with thyroaplasia.
- Laurer c. a tube originating on the surface of the ootype of trematodes, directed dorsally to or near the surface; it may have originally served as a vagina or possibly as a reservoir of excess shell material.
- Leeuwenhoek canals SYN: haversian canals.
- lesser palatine canals [TA] canals located in the posterior part of the palatine bone. SYN: canales palatini minores [TA], canals for lesser palatine nerves.
- longitudinal canals of modiolus [TA] centrally placed channels that convey vessels and nerves to the apical turns of the cochlea. SYN: canales longitudinales modioli [TA], central canals of cochlea.
- Löwenberg c. SYN: cochlear duct.
- mandibular c. [TA] the c. within the mandible that transmits the inferior alveolar nerve and vessels. Its posterior opening is the mandibular foramen. SYN: canalis mandibulae [TA], inferior dental c..
- musculotubal c. [TA] a c. beginning at the anterior border of the petrous portion of the temporal bone near its junction with the squamous portion, and passing to the tympanic cavity; it is divided by the cochleariform process into two semicanals: one for the pharyngotympanic (auditory) tube, the other for the tensor tympani muscle. SYN: canalis musculotubarius [TA].
- nasolacrimal c. [TA] the bony c. formed by the maxilla, lacrimal bone, and inferior concha that transmits the nasolacrimal duct from the orbit to the inferior meatus of the nose. SYN: canalis nasolacrimalis [TA].
- neurenteric c. a transitory communication between the neural tube, notochordal c., and gut endoderm in vertebrate embryos.
- notochordal c. SYN: archenteric c..
- c. of Nuck processus vaginalis of peritoneum.
- nutrient c. [TA] a c. in the shaft of a long bone or in other locations in irregular bones through which the nutrient artery enters a bone. SYN: canalis nutricius [TA].
- obturator c. [TA] the opening in the superior part of the obturator membrane through which the obturator nerve and vessels pass from the pelvic cavity into the thigh. SYN: canalis obturatorius [TA].
- optic c. [TA] the short c. through the lesser wing of the sphenoid bone at the apex of the orbit that gives passage to the optic nerve and the ophthalmic artery. SYN: canalis opticus [TA], foramen opticum, optic foramen.
- palatovaginal c. [TA] on the undersurface of the vaginal process of the sphenoid bone, a furrow that is converted into a c. by the sphenoidal process of the palatine bone; it transmits the pharyngeal branch of the maxillary artery and the pharyngeal nerve from the pterygopalatine ganglion. SYN: canalis palatovaginalis, pharyngeal c..
- parturient c. SYN: birth c..
- pericardioperitoneal c. the portion of the embryonic celom that joins the pericardial cavity to the peritoneal cavity, developing into the pleural cavities. SYN: pleural c..
- persistent atrioventricular c. a condition that is caused when the atrial and ventricular septa fail to meet, as in normal development, resulting in a low atrial and high ventricular septal defect or a common atrioventricular c.. SYN: endocardial cushion defect.
- pharyngeal c. SYN: palatovaginal c..
- c. for pharyngotympanic (auditory) tube [TA] the inferior division of the musculotubal c. that forms the bony part of the pharyngotympanic (auditory) tube. SYN: semicanalis tubae auditivae [TA], semicanal of auditory tube, semicanalis t′ubae audito′riae.
- pleural c. SYN: pericardioperitoneal c..
- pleuropericardial canals in the embryo, spaces or channels, one on each side, connecting the pericardial and pleural cavities.
- portal canals connective tissue spaces in the substance of the liver that are occupied by preterminal ramifications of the bile ducts, portal vein, and hepatic artery, as well as nerves and lymphatics.
- pterygoid c. [TA] an opening through the base of the medial pterygoid process of the sphenoid bone through which pass the artery, vein, and nerve of the pterygoid c.. SYN: canalis pterygoideus [TA], vidian c..
- pterygopalatine c. SYN: greater palatine c..
- pudendal c. [TA] the space within the obturator internus fascia lining the lateral wall of the ischioanal (ischiorectal) fossa that transmits the pudendal vessels and internal pudendal nerves. SYN: canalis pudendalis [TA], Alcock c..
- pyloric c. [TA] the aboral segment (about 2–3 cm long) of the stomach; it succeeds the antrum and ends at the gastroduodenal junction. SYN: canalis pyloricus [TA].
- root c. of tooth [TA] the chamber of the dental pulp lying within the root portion of a tooth. SYN: canalis radicis dentis [TA], marrow c., pulp c..
- canals of Scarpa separate canals for the nasopalatine nerves and vessels. These canals normally fuse to form the incisive c..
- semicircular canals of bony labyrinth [TA] the organ of balance; the three bony tubes in the labyrinth of the ear within which the membranous semicircular ducts are located; they lie in planes at right angles to each other and are known as anterior semicircular c., posterior semicircular c., and lateral semicircular c.. SYN: bony semicircular canals, canales semicircularis ossei.
- Sondermann c. a blind outpouching of Schlemm c., extending toward, but not communicating with, the anterior chamber of the eye.
- spiral c. of cochlea [TA] the winding tube of the bony labyrinth that makes two and a half turns about the modiolus of the cochlea; it is divided incompletely into two compartments by a winding shelf of bone, the bony spiral lamina. SYN: canalis spiralis cochleae [TA], cochlear c., Rosenthal c..
- spiral c. of modiolus [TA] the space in the modiolus in which the spiral ganglion of the cochlear nerve lies. SYN: canalis spiralis modioli [TA].
- subsartorial c. SYN: adductor c..
- Sucquet-Hoyer canals arteriovenular anastomoses controlling blood flow in the glomus bodies in the digits. SYN: Hoyer anastomoses, Hoyer canals, Sucquet anastomoses, Sucquet canals, Sucquet-Hoyer anastomoses.
- temporal c. a c. in the zygomatic bone transmitting the zygomaticofacial and zygomaticotemporal nerves and vessels.
- c. for tensor tympani muscle [TA] semicanal of the tensor muscle of the tympanum; the superior division of the musculotubal c. containing the tensor tympani muscle. SYN: semicanalis musculi tensoris tympani [TA], semicanal for tensor tympani muscle.
- Theile c. SYN: transverse pericardial sinus.
- tubotympanic c. tubotympanic recess.
- uniting c. SYN: ductus reuniens.
- uterovaginal c. a median tubular structure produced in the embryo from the fusion of the caudal parts of the paramesonephric ducts.
- van Horne c. SYN: thoracic duct.
- vertebral c. [TA] the c. that contains the spinal cord, spinal meninges, and related structures. It is formed by the vertebral foramina of successive vertebrae of the articulated vertebral column. SYN: canalis vertebralis [TA], spinal c., tubus vertebralis.
- vesicourethral c. the cranial portion of the primitive urogenital sinus from which develop the urinary bladder and part of the urethra.
- vestibular c. SYN: scala vestibuli.
- Volkmann canals vascular canals in compact bone that, unlike those of the haversian system, are not surrounded by concentric lamellae of bone; they run for the most part transversely, perforating the lamellae of the haversian system, and communicate with the canals of that system.
- vomerine c. SYN: vomerovaginal c..
- vomerobasilar c. SYN: vomerorostral c..
- vomerorostral c. [TA] a small c. between the superior border of the vomer and the rostrum of the sphenoidal bone. SYN: canalis vomerorostralis [TA], vomerobasilar c..
- vomerovaginal c. [TA] an opening between the vaginal process of the sphenoid and the ala of the vomer on either side. It conveys a branch of the sphenopalatine artery. SYN: canalis vomerovaginalis [TA], basipharyngeal c., vomerine c..
- Wirsung c. SYN: pancreatic duct.
* * *
ca·nal kə-'nal n a tubular anatomical passage or channel: DUCT see ALIMENTARY CANAL, HAVERSIAN CANAL, INGUINAL CANAL
* * *
n.
a tubular channel or passage; e.g. the alimentary canal and the auditory canal of the ear.
* * *
ca·nal (kə-nalґ) a relatively narrow tubular passage or channel; see also canalis.For descriptions of specific anatomic structures not found here, see under canalis.
Medical dictionary. 2011.