tragocamelus; temporal fossa relatively slightly shorter; occipital less convex transversely over the foramen magnum
and less hollowed on either side of the median vertical line; occipital condyles much wider and projecting farther in rear of the occipital crest; foramen magnum
much larger; paraoccipital process less compressed laterally" (Pilgrim, 1939).
The foramen magnum
, Latin for "great opening", is an aperture in the occipital bone of the skull and the largest of the skull's foramina (Fig.
Posteroinferiorly, the lesion is infiltrating the foramen magnum
with associated obliteration of anterior thecal sac space and significant extradural compression of the cervicomedullary region of the brain stem, which is seen pushed to the left.
It ascents through foramina transversaria of all six cervical vertebrae and enters into cranial cavity through foramen magnum
to supply different part of the brain after the formation of a circle of Willis.
12) The artery is most prone to injury between the entrance to the transverse foramen of C6 and the foramen magnum
(V2 and V3 segments).
Titled "Another look at the foramen magnum
in bipedal mammals," (http://www.
No Anatomical landmarks definitions 1 Minimum frontal breadth Distance between the two frontotemporale (ft) 2 Biorbital breadth Distance between right and left ectoconchion (ec) 3 Bizygomatic diameter Distance between most lateral points on the zygomatic arches 4 Nasal breadth Maximum breadth of the nasal aperture 5 Orbital height Distance between the superior and inferior orbital margins 6 Foramen magnum
breadth Distance between the lateral margins of foramen magnum
at the points of greatest lateral curvature 7 Foramen magnum
length Distance from basion (ba) to opisthion (o) 8 Foramen ovale Distance between left and right of foramen ovale 9 Foramen spinosum Distance between left and right of foramen spinosum Table 4: Dimensional measurements of dry skull and CAD models.
Fifty nine of these were done for 4th ven-tricle/cerebellar sols, twelve for foramen magnum
SOLs, and six for chiari malformations.
sup], They mostly locate in the prepontine region, rarely in the intrasellar, suprasellar, pterional region, pineal, dorsum sellae, Meckel's cave, cerebellum, hypothalamus, tentorium cerebella, and foramen magnum
In this skull, median or third occipital condyle is seen along the anterior margin of foramen magnum
Lymphoplasmacyte-rich meningioma at the foramen magnum
1 There was a time when lots of scholars acknowledging the crowding theory which postulated that restricted growth of the posterior fossa causes compression of neural tissue, which is then squeezed through the foramen magnum
like toothpaste through a tube.