Cranium Flashcards
The meninges surrounds the spinal cord and brain, but there is a difference between the meningeal coverings of the brain and spinal cord. What is that difference?
In the cranium, the dura mater is fused to the periosteum
___________ is a dural fold that separates the cerebral hemispheres.
Falx cerebri
___________ is a dural fold that separates the right and left cerebellar hemispheres.
Falx cerebelli
The ___________ separates the cerebellum from the occipital lobe of the cerebral cortex.
Tentorium cerebelli
*Dura mater proper (not fused)
NOTE: The tentorium cerebelli covers the posterior cranial fossa
The pituitary gland is surrounded by the _____________.
Diaphragm sella
- The diaphragm through which the pituatary stalk goes from the pituitary gland and attaches to the hypothalamus
What are the two parts of the pituitary gland and what are the embryonic origins of each?
Anterior pituitary: Develops as the diverticulum of the developing mouth (Rathke’s pouch)
Posterior Pituitary : Develops from the brain itself (extension of the hypothalamus)
Tumors can form from both parts of the pituitary. Which types of tumors can form from each?
Anterior pituitary: Craniopharyngioma (forms from embryonic tissue and common in children
Posterior pituitary: Pituitary ademoma (common in adults)
Pituitary adenoma begins as ______________
Bitemporal superior quadrantanopsia
* A loss of vision in a quarter section of the visual field
of both eyes.
Craniopharyngioma begins as ____________.
Bitemporal inferior quadrantanopsia
As the pituitary adenoma tumor grows through the diaphragm sella, it has no where to expand to except anteriorly. This expansion puts pressure on the ______________.
Optic chiasm
*The axons in the optic chiasm are collecting visual info about the periphery.
What are the results of pressure on the optic chiasm, caused by the growing pituitary adenoma?
- Bitemporal tunnel vision
- Loss of vision in upper lateral quandrants
NOTE: The central field of vision is in tact
What are symptoms of a craniopharyngioma?
- Bitemporal vision loss in the lower lateral quandrants of the visual field
- Headache
- Vomiting
- Difficulty sleeping
- Extreme thirst
Does the brain have nerve endings?
No.
*The dura mater that covers the brain has sensory nerve endings
Which nerve primarily supplies the dura mater?
The trigeminal nerve
Which nerve supplies the dura over the anterior fossa?
The opthalamic nerve (V1)
Which nerve supplies the tentorium cerebrelli?
The opthalamic nerve (V1)
*A small part is also supplies by the mandibular nerve (Which nerve supplies the anterior fossa (V3)
Which nerve supplies the dura over the greater wing of the sphenoid (in the middle cranial fossa)?
Maxillary nerve (V2)
Which nerve supplies the dura of the back part of the middle cranial fossa?
Mandibular nerve (V3)
What innervates the dura mater of the posterior cranial fossa?
Sensory branches of C2 and C3
Pain from the dura is usually described as __________
Headache
What role do inflammed blood vessels play in headache?
Inflammation of the blood vessels supplying the dura irritates and stimulates the sensory fibers of the nerves innervating the dura mater causing headache
What artery supplies the dura?
The middle meningeal artery
*Runs between the skill and the periosteum
The middle meningeal artery is a branch of the ____________ artery in the infratemporal fossa
Maxillary
The middle meningeal artery is surrounded by the _____________ nerve.
Auricular temporal nerve
*The splitting of the auricular temporal nerve by the middle meningeal artery helps indentification of the different branches