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The opening in the central tendon of the diaphragm through which the vena cava passes from the abdominal cavity into the thoracic cavity.
See also: foramen
pl. foramina [L.] a natural opening or passage, especially one into or through a bone.
a foramen which perforates the wing of the atlas in some species and transmits the vertebral artery; appears as a notch in dogs.
the opening at or near the apex of the root of a tooth and into the dental cavity.
auditory foramen (external)
the external acoustic meatus.
auditory foramen (internal)
the passage for the auditory (vestibulocochlear) and facial nerves in the pars petrosa of the temporal bone. Called also internal acoustic meatus.
caudal palatine foramen
the caudal opening into the greater palatine canal.
one of the three openings in the diaphragm; situated in the central tendinous part of the diaphragm; called also vena caval foramen, foramen venae cavae.
cecal foramen, foramen cecum
a blind opening between the frontal crest and the crista galli.
foramen cecum linguae
an occasional finding in humans; marks the boundary of the caudal and rostral contributions to the tongue, the site of the origin of the thyroid gland; called also cecum foramen.
condyloid foramen (anterior)
condyloid foramen (posterior)
an opening connecting the omental bursa with the rest of the abdominal cavity; situated on the visceral surface of the liver dorsal to the portal fissure. Called also foramen of Winslow.
e. foramen hernia strangulation
rare cause of acute intestinal obstruction in horses.
one of the openings of the incisive canals into the incisive fossa of the hard palate.
the facial opening of the infraorbital canal, a prominent feature of the lateral aspect of the face; provides a point of emergence for the infraorbital nerve.
a passage from the third to the lateral ventricle of the brain.
a passage for a spinal nerve and vessels formed by notches on the pedicles of adjacent vertebrae.
an opening formed by the jugular notches of the temporal and occipital bones.
the irregular gap between the basioccipital, petrous temporal and sphenoid wing bones, making up a large, membrane-covered foramen in horses, but reduced to a slit in other domestic mammals.
a large opening in the occipital bone, between the cranial cavity and spinal canal.
foramen magnum herniation
see transtentorial herniation.
in the medial surface of the mandible; inferior alveolar vessels and nerve enter here.
one of the foraminae ventral to the orbit; leads to the infraorbital canal.
foramina on the lateral aspect of the mandible from which the inferior alveolar nerve and blood vessels emerge to supply the chin.
an opening in the temporal bone behind the mastoid process.
foramen of Monro
the entrance for the nutrient artery of a bone.
the large opening between the pubic bone and the ischium.
the opening into the optic canal.
transmits ophthalmic branch of trigeminal, oculomotor, abducent and trochlear nerves. Called also orbital fissure.
the copy, in pigs and ruminants, of the orbital foramen in other species.
1. the septal opening in the fetal heart that provides a communication between the atria. The opening closes at birth; failure to close results in atrial septal defect.
2. an aperture in the great wing of the sphenoid for vessels and nerves.
palatine foramen (anterior)
greater and lesser foramina in the hard palate for conduction of palatine vessels.
apertures in avian bones which connect with air sacs making pneumatization of bone marrow cavities possible.
opening in the septum primum between the two atria of the embryonic heart; called also ostium primum.
the external opening of the temporal canal just caudal to the zygomatic arch; this foramen provides an exit for a large vein, the transverse sinus which drains the cranial cavity.
foramen rotundum, round foramen
a round opening in the great wing of the sphenoid for the exit of the maxillary branch of the trigeminal nerve from the cranial cavity; in ruminants it is combined with the orbital fissure.
see foramen rotundum (above).
sacral foramen (dorsal)
passage on the dorsal surface of the sacrum for the dorsal branches of the sacral nerves.
sacral foramen (ventral)
passage on the pelvic surface of the sacrum for the ventral branches of the sacral nerves.
an opening behind the upper medial incisor, for the nasopalatine nerve.
either of two foramina, the greater and the lesser sciatic foramina, formed by the sacrotuberal and sacrospinous ligaments in the sciatic notches of the hip bone.
the second of the two orifices to perforate the septum primum between the cardiac atria; forms through cell death. Called also ostium secundum.
a space between the orbital and sphenoidal processes of the palatine bone, opening into the nasal cavity and transmitting the sphenopalatine artery and the nasal nerves.
a hole in the great wing of the sphenoid for the middle meningeal artery.
the opening of the facial canal, adjacent to the ear from which the facial nerve emerges.
a fissure in the mediodistal part of the humerus in cats through which the median nerve and vessels pass.
passage in the frontal bone for the supraorbital vessels and nerve; often present as a notch bridged only by fibrous tissue.
minute openings in the walls of the heart through which the smallest cardiac veins (thebesian veins) empty into the cardiac chambers.
the passage in either transverse process of a cervical vertebra that, in the first six vertebrae, transmits the vertebral vessels.
the hole between the ends of the avian clavicle, coracoid and scapula that transmits the tendon of the supracoracoid muscle and serves as a fulcrum to lever the wing upwards.
vena cava foramen
an opening in the diaphragm for the caudal vena cava.
1. the large opening in a vertebra formed by its body and its neural arch.
2. transverse foramen.
foramen of Vesalius
an occasional opening medial to the foramen ovale of the sphenoid, for passage of a vein from the cavernous sinus.
foramen of Winslow