Ch4 Meningeal Coverings Flashcards
3 layers of meningeas are : ___ ____ ___
Dura, Arachnoid, Pia
What is the function of Meningeas ?
provide protection and structural support:
keeps brain from collapsing and cushions against movements
Meningeas are attached to the skull and so makes the brain moves with the head (otherwise would slosh and spine around like ice in glass)
Dura matter is continuously attached except for two spaces : ____ (btw ___) and ___ (btw ___)
epidural space (btw dura and skull) and subdural space (btw dura and arachnoid)
What is Dural Septum ?
Dural Septum is where the dura folds into the brain fissures
There are two major dural septa: ___ (Where? ____ ) and _____ (Where? ___ )
flax cerebra (dura sheet in between hemisphere) and tentorium cerebelli (dura sheet between cerebellum and cerebellum)
tentorium cerebelli has two compartments: What and Where ?
supratentorium (cerebrum) and infratentoriem (cerebellum and brainstem)
____ is where the two layers of dura separated.
Dural Venous Sinuses
What are the three major sinuses and where ?
- superior sagittal sinus (attached to flax)
- transverse sinus (L & R) runs along cerebellum
- sigmoidal sinus (L & R) continous part of transverse going along cerebrum.
What are the two sensory endings in Dura matter ?
Dura has sensory endings : the trigeminal nerve and the vagus nerve (receved in posterior fossa)
What do call the connective tissue between dura and arachnoid?
arachiod trabeculae
______ = where the arachnoid space becomes wide, and where arachnoid bridges over small sulci and large surface irregularities
subarachnoid cisterns
Two popular cisterns are _____ and _____
cisterna magna (btw cerebellum and medulla) and ambient cistern (superior cistern)
The arachnoid have villi, the large ones are called ________
arachnoid granulations
what is the function of villi ? describe the one-way strategy in villis
villi are major sites for reabsorption of CSF into venous system..
one-way valves that let CSF out of arachnid into the sinuses and absorbed into the venous blood.
Space around blood vessels and brain is called __________
perivascular space or Volchow-Robin spaces.
What is the difference between meningeas in brain and spinal chord ?
- Dura : instead of 2 layers, spinal cord has one layer suspended in CSF on both sides (the outside of the spinal cord is dura)
- subarachnoid space around spinal cord just like around brain, where CSF circulates.
- Arachnoid attached to pia by connective tissue, but in spinal cord called denticulate ligaments (look like teeth) [lumbar cistern?]
_______ = Meningeal arteries bwtween skull and dura can get torn and cause a bleed
Epidural Hematoma
_____= Veins that enter the sinuses can also get torn.
subdural Hematoma
