round foramen

fo·ra·men ro·tun·'dum

[TA]

an opening in the base of the greater wing of the sphenoid bone, transmitting the maxillary nerve.

Synonym(s): round foramen

round foramen

one of a pair of rounded apertures in the greater wings of the sphenoid bone.

foramen

pl. foramina [L.] a natural opening or passage, especially one into or through a bone.

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alar foramen

a foramen which perforates the wing of the atlas in some species and transmits the vertebral artery; appears as a notch in dogs.

apical foramen

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.

caval foramen

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)

hypoglossal canal.

condyloid foramen (posterior)

condylar canal.

epiploic foramen

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.

incisive foramen

one of the openings of the incisive canals into the incisive fossa of the hard palate.

infraorbital foramen

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.

interventricular foramen

a passage from the third to the lateral ventricle of the brain.

intervertebral foramen

a passage for a spinal nerve and vessels formed by notches on the pedicles of adjacent vertebrae.

jugular foramen

an opening formed by the jugular notches of the temporal and occipital bones.

foramen lacerum

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.

foramen magnum

a large opening in the occipital bone, between the cranial cavity and spinal canal.

foramen magnum herniation

see transtentorial herniation.

mandibular foramen

in the medial surface of the mandible; inferior alveolar vessels and nerve enter here.

maxillary foramen

one of the foraminae ventral to the orbit; leads to the infraorbital canal.

mental foramen

foramina on the lateral aspect of the mandible from which the inferior alveolar nerve and blood vessels emerge to supply the chin.

mastoid foramen

an opening in the temporal bone behind the mastoid process.

foramen of Monro

interventricular foramen.

nutrient foramen

the entrance for the nutrient artery of a bone.

obturator foramen

the large opening between the pubic bone and the ischium.

optic foramen

the opening into the optic canal.

orbital foramen

transmits ophthalmic branch of trigeminal, oculomotor, abducent and trochlear nerves. Called also orbital fissure.

orbitorotundum foramen

the copy, in pigs and ruminants, of the orbital foramen in other species.

foramen ovale

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.

pneumatic foramen

apertures in avian bones which connect with air sacs making pneumatization of bone marrow cavities possible.

foramen primum

opening in the septum primum between the two atria of the embryonic heart; called also ostium primum.

retroarticular foramen

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.

round foramen

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.

Scarpa's foramen

an opening behind the upper medial incisor, for the nasopalatine nerve.

sciatic foramen

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.

foramen secundum

the second of the two orifices to perforate the septum primum between the cardiac atria; forms through cell death. Called also ostium secundum.

sphenopalatine foramen

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.

spinous foramen

a hole in the great wing of the sphenoid for the middle meningeal artery.

stylomastoid foramen

the opening of the facial canal, adjacent to the ear from which the facial nerve emerges.

supracondylar foramen

a fissure in the mediodistal part of the humerus in cats through which the median nerve and vessels pass.

supraorbital foramen

passage in the frontal bone for the supraorbital vessels and nerve; often present as a notch bridged only by fibrous tissue.

thebesian foramen

minute openings in the walls of the heart through which the smallest cardiac veins (thebesian veins) empty into the cardiac chambers.

transverse foramen

the passage in either transverse process of a cervical vertebra that, in the first six vertebrae, transmits the vertebral vessels.

foramen triosseum

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.

vertebral foramen

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

epiploic foramen.