2. History
Herophilos
335–280 or 255 BC. Anatomist. Alexandria
Aristotle
384 – 322 BC. Greek philosopher and scientist born
in the Macedonian
------------------------------------------ then
Thomas Willis,1664, English Anatomist
Jean Pierre Flourens, 1800, French physiologist
----------------------------------------- then
1st half of 20th century
3. Posterior cranial fossa
• 1/8 of the intracranial space
• Regulating
1. Consciousness
2. Vital autonomic functions
3. Motor & Sensory reception
4. Controlling gait and balance
4.
5. • Through the tentorium incisura
Communicates with the supratentorial spaces
• Through the foramen magnum
Communicates with spinal cord
6. Intracranial surface of posterior fossa
is penetrated by
• Jugular foramen
Cr. Ns IX, X, and XI & IJV
• Internal acoustic meatus
Cr. N. VII, VIII, and the labyrinthine artery (an internal auditory
branch of the basilar artery).
& the vestibular ganglion « scarpa ganglion « october 1772
• Hypoglossal canal
Cr. N. XII
• Vestibular & cochlear aqueducts
• Several venous emissary foramina
7. .
• Site
Lies in posterior fossa on the occipital bone posteriorly &
close to the mastoid air cells anteriorly
Separated : occipital lobe by the tentorium &
the pons and midbrain by the 4th vent.
It is related to Dural sinus, especially sigmoid sinuses.
8. Surfaces
• The surface is named by the structure it
faces, to make the description more
applicable
• Surfaces :
Tentorium surface, faces tentorium
Suboccipital surface, between the sigmoid &
transverse sinuses
Petrosal surface, faces the post. Surface of petrous
bone & retracted to expose the cerebellopotine angle
42. Developmental anatomical
pathologies
• underdevelopment (hypoplasia) of the
cerebellar vermis is a characteristic of both
Dandy–Walker syndrome
• Herniation of cerebellar tissue, as seen in
some forms of Arnold–Chiari malformation