What is basioccipital hypoplasia?
Basiocciput hypoplasia results in shortening of the clivus and is always associated with basilar invagination. There is an increased prevalence of neural dysgenesis, such as the Chiari malformation or syringohydromyelia, reported to occur in 25%–35% of patients with basilar invagination.
What is the Basioccipital bone?
Medical Definition of basioccipital (Entry 1 of 2) : relating to or being a bone in the base of the cranium immediately in front of the foramen magnum that is represented in humans by the basilar process of the occipital bone.
What is hypoplastic clivus?
Basioccipital hypoplasia has been defined as hypoplasia of ≥1 of the 5 clival segments (sclerotomes) of the clivus (simplified from Fujita et al14). Basilar invagination is commonly defined as cranial displacement of >5 mm of the tip of the odontoid above to the Chamberlain line.
Where is clivus?
skull
A bone at the base of the skull, near the spine.
What is the pharyngeal tubercle?
On the lower surface of the basilar part of occipital bone, about 1 cm. in front of the foramen magnum, is the pharyngeal tubercle which gives attachment to the fibrous raphC) of the pharynx, also known as the pharyngeal raphe. This is the point of attachment for the superior pharyngeal constrictor muscle.
What part of sphenoid articulates with basioccipital?
The sphenoid bone body is in the midline with its posterior aspect (dorsum sellae) articulating inferiorly through a synchondrosis with the basioccipital bone forming the clivus. Lesser and greater wings extend on either side of the body.
Where is sphenoid?
An unpaired bone located in the cranium (or skull), the sphenoid bone, also known as the “wasp bone,” is located in the middle and toward the front of the skull, just in front of the occipital bone.
What is the purpose of clivus?
The clivus is an important landmark for checking for anatomical atlanto-occipital alignment; the clivus, when viewed on a lateral C-spine X-ray, forms a line which, if extended, is known as Wackenheim’s clivus line. Wackenheim’s clivus line should pass through the dens of the axis or be tangential to it.
What does the clivus do?
The clivus protects the brainstem and posterior cranial fossa. A thorough appreciation of the anatomy of these various areas allows for endoscopic endonasal approaches to the skull base 1). Penetration of the clivus is required for surgical access of the brainstem.
What passes through the hypoglossal canal?
Function. The hypoglossal canal transmits the hypoglossal nerve from its point of entry near the medulla oblongata to its exit from the base of the skull near the jugular foramen.