foramen magnum


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foramen magnum

n.
The large orifice in the base of the skull through which the spinal cord passes to the cranial cavity and becomes continuous with the medulla oblongata.

[New Latin forāmen magnum : Latin forāmen, opening + Latin magnus, large.]

foramen magnum

n
(Anatomy) the large opening at the base of the skull through which the spinal cord passes
[New Latin: large hole]

fora′men mag′num

(ˈmæg nəm)
n.
the large opening in the base of the skull through which the spinal cord merges with the brain.
[1880–85; < New Latin: literally, large hole]
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.foramen magnum - the large opening at the base of the cranium through which the spinal cord passesforamen magnum - the large opening at the base of the cranium through which the spinal cord passes
braincase, brainpan, cranium - the part of the skull that encloses the brain
foramen, hiatus - a natural opening or perforation through a bone or a membranous structure
References in periodicals archive ?
Generally, when a part of the cerebellum, which is known as cerebellar tonsils, is located under the foramen magnum, it is known as a Chiari malformation.Chiari malformation is categorised into four types: Type I Chiari malformation is asymptomatic.
The company also plans to augment the height Z-score data with assessments including proportionality, functionality, quality of life, sleep apnea, and foramen magnum dimension, as well as the advent of major illnesses and surgeries.
In patients with CM, due to the compression of the cerebellum at the posterior fossa and foramen magnum the symptoms related to cerebellar dysfunction such as dizziness, imbalance, and dysmetria can be observed.
d) Skull base length (LBsk): Distance between the midpoints of the dorsal margin of the foramen magnum to the level of the middle point of the rostral margin of the incisive bone.
Individuals living with achondroplasia may experience severe skeletal complications and comorbidities, including narrowing of the foramen magnum, sleep apnea and chronic ear infections.
In the analysis results, delayed enhancement was observed at the extraparenchymal subarachnoid space (foramen magnum, pontine cistern, Sylvian fissure) in patients with INPH.
This hypothesis is tested by measuring interval distances between relevant brain structures and fixed anatomically based planes of reference both at the tentorial hiatus and at the foramen magnum in both normal and IH patient populations.
The image ranges of each class were defined as follows: brain, slice from the anterior tip of the parietal bone to the foramen magnum; neck, slice from the foramen magnum to the pulmonary apex; chest, slice from the pulmonary apex to the diaphragm; abdomen, slice from the diaphragm to the top of an iliac crest; and pelvis, slice from the top of an iliac crest to the distal end of the ischium.
MRI of the cervical spine revealed spinal cord compression at the level of the foramen magnum secondary to a craniocervical junction anomaly with severe kyphosis of the upper cervical spine at the level of C3-C4 (Figure 1).
The lower part of the cerebellum, but not the brain stem, extends into the foramen magnum at the base of the skull [3].