Meninges Flashcards
What are the functions of the meninges?
To stabilize, anchor, and cushion the brain.
The dura mater consists of two layers. What are they called?
The periosteal layer (attached to the skull) and the meningeal layer (attached to arachnoid).
Where are the meningeal arteries located?
Within the periosteal layer of the dura mater.
The meningeal layer of the dura mater has two projections. What are they called?
The falx cerebri (separates the two cerebral hemispheres) and the tentorium cerebelli (separates the cerebellum from the cerebral hemispheres).
True or false: The dura mater is pain sensitive.
True. The middle fossa is innervated by CN V and the posterior fossa is innervated by CN X.
What two spaces between meningeal layers are considered potential spaces?
The epidural (extradural) space (between the cranium and the periosteal layer of the dura) and the subdural space (between the meningeal layer of the dura and the arachnoid).
What is often the cause of an epidural hematoma?
Traumatic head injury, often involving a fracture to the temporal bone. The middle meningeal artery is most often the source of the bleed.
True or false: Epidural hematomas develop rapidly.
False. Their development is slow due to the difficulty in separating periosteal dura from the bone of the skull.
How would an epidural hematoma show up on a CT scan?
It would appear as a lens-shaped blood collection with a convex medial border. It would also respect the suture lines.
What is the cause of a subdural hematoma?
Severe head injury, leading to the rupture of a bridging vein; hence leading to a thin layer of blood in the subdural space.
How would a subdural hematoma show up on a CT scan?
It would appear as a crescent-shaped blood collection with a concave medial border. It would not respect the suture lines.
Where is the superior sagittal sinus located?
It runs in the fixed margin of the falx cerebri.
Where is the inferior sagittal sinus located?
It runs in the concave free margin of the falx cerebri.
Where is the straight sinus located?
It runs along the attachment of the falx cerebri to the tentorium cerebelli.
Where is the transverse sinus located?
Along the outer border of the tentorium cerebelli.
