L6 Meninges and Arteries Flashcards
what does the subarachnoid space follow
fissures not sulci
what is a cistern?
expansion of the subarachnoid space resulting from irregularity of the surface of the brain, which is lined by pia mater
what layers is the superior sagital sinus between?
2 layers of dura - periosteal and meningeal dura
arachnoid mater: vascular or avascular?
avascular
pia mater: vascular or avascular?
highly vascular
what is the falx cerebri
arched fold of dura mater that descends vertically in the longitudinal fissure between the cerebral hemispheres. - meningeal dural layer!
where do cerebral hemorrhages lie?
between arachnoid mater and pia mater
most dangerous hemorrhage in brain?
epidural
which brain hemorrhage is difficult to address surgically?
subarachnoid hemorrhage
what will pt with subarachnoid hemorrhage complain of?
terrible headache - blood is very irritating to meninges
what ruptures with a intracerebral hemorrhage?
intraparenchymal branches of the subarachnoid a. = lenticulostriate a. – branch of middle cerebral a. supplying internal capsule and BG
ventricles dilate!
what layer of meninges do spinal cords lack>
no periosteal dura!
what 2 arteries anastomose to form the circle of willis at the basal diencephalon? what do they supply?
vertebral a. and internal carotid a.
basilar, cerebellar and cerebral a.
where are all the brain vessels contained?
within subarachnoid space
what artery feeds the middle and anterior cerebral a.?
internal carotid a.
what branches do the middle cerebral a give off?
linticulaostriate a.
what does the anterior communicating a. connect?
the two anterior cerebral a.
where is a popular place for an aneurysm?
ant. communicating a. (very close to optic chasm)
where do posterior cerebral a. come from?
basilar a.
what does the middle cerebral a. supply?
lateral cerebral surface
what does the ant. cerebral a. supply?
anteromedial cerebral surface
what does the post. cerebral a. supply?
posteromedial cerebral surface
what a. supplies the anterior and posterior spinal a.?
spinal medullary arteries – segmental branches of vertebral a. and aorta
which is more vulnerable ant or post spinal a?
anterior
how much of my body weight is my brain?
2%
how much of CO is contributed to brain?
15%
how much oxygen does the brain consume?
20%
what is the flow of blood in brain?
750-1000 ml/min
what controls cerebral blood flow>
metabolic control - pH, pCO2, adenosine, glycolytic products, extracellular K+ neurogenic control - sympathetic - parasympathetic - trigeminal peripheral CO2 autoregulation
What happens if you mess with the vertebral a.?
You mess with medullary pyramid = motor = one side of the body will go weak
Say the middle cerebral a. Ruptures and kills the left side of the brain. Which side of the body will it affect?
The right side…
