The posterior cranial fossa (dave's notes) Flashcards
What are the contents of the posterior cranial fossa?
the convexities of the cerebral hemispheres, the pons and the medulla oblongata
What pierces the dura mater from the posterior cranial fossa?
The 5th to 12th cranial nerves.
Describe the origin of the trigeminal nerve
Leaves the AL?? part of the pons in two roots, large sensory and small motor, heads to the trigeminal cave
Describe the origin of the abducent nerve
Leaves near the vertical midline at the junction between pons and pyramidal lobes, runs up, and evaginates the dura to run to the inferior petrosal sinus, then to the cavernous sinus.
Why is the abducent nerve a good indicator of ICP?
It has a long intracranial course so is vulnerable to raised ICP
Where do the facial and vestibulocochlear nerves leave the ??mid brain
From the pos/medulla junction passing laterally and upwards to the internal acoustic meatus.
What lies with the facial and vestibulocochlear nerves?
The labyrinthine artery
What is lateral to the petrous bone?
The internal acoustic meatus
What is found in the petrous bone?
The cochlear with the vestibule behind. The nerve lies above the vestibule.
What leaves from the side wall of the medulla oblongata? Via what route to these leave the cranium?
The GPN, vagus and accessory nerves. These pass laterally across the occipital bone to the jugular foramen.
Where does the hypoglossal nerve leave the brain?
Leaves the medulla via a series of rootless (between the pyramid and olive), to create two roots that enter the hypoglossal canal separately.
What arteries are found in the posterior cranial fossa?
The two vertebral and the basilar.
