Lecture 19 Flashcards
what is the jobs of the cranial meninges
- protect the brain
- form supporting framework for vasculature and venous sinuses
- enclose the cerebrospinal fluid filled subarachnoid space
where do the cranial meninges lie
lie immediately deep to the cranium
order of the meninge layers
dura mater
arachnoid mater
pia mater
what is the space between the arachnoid mater and pia mater
subarachnoid space
what is the subarachnoid space filled with
cerebrospinal fluid
how does the cranial dural mater differ than the spinal dura mater
it consists of a outer periosteal layer and an inner meningeal layer
what are the four dural infoldings
falx cerebri
tentorium cerebelli
falx cerebelli
diaphragma sellae
what does the falx cerebri separate
lies in the longitudinal cerebral fissure to seperate the cerebral hemispheres
what does the tentorium cerebelli separate
the occipital lobes of cerebrum from the cerebellum; divides the cranial cavity into supratentorial and infratentorial compartments
what is the purpose of the falx cerebelli
partially separates the cerebellar hemispheres as it lies inferior to tentorium cerebelli
location of the diaphragma sellae
horizontal shelf of meningeal dura mater - suspended between the clinoid processes, forming the roof of the sella turcica that covers the pituitary gland
bony landmarks for the falx cerebri
anteriorly = frontal crest of frontal bone and crista gali of ethmoid bone
Posteriorly = internal aspect of occipital protuberance
bony landmarks for the tentorium cerebelli
clinoid processes of sphenoid bone, pertrous part of temporal bone, parietal and occipital bones
what are arachnoid granulations
visible as outward bulges of the dura mater. transfer CSF to the venous system
what are dural venous sinuses
endothelial-lined spaces, located within the dura, between the periosteal and meningeal dural layers
how many dural sinuses are there
7
what dural sinus lies in the superior border of the falx cerebri
superior sagittal sinus
boney landmarks of the superior sagittal sinus
begins at the crista galli, ends near the internal occipital protuberance at the confluence of sinuses
what dural sinus lies in the inferior border of the falx cerebri
inferior sagittal sinus
where does the inferior sagittal sinus end
into the straight sinus
location of the straight sinus
runs along the line of attachment of the falx cerebri and the tentorium cerebelli
what does the straight sinus join
the confluence of sinuses
where does the occipital sinus lie
posterior border of falx cerebelli
where does the occipital sinus end
superiorly at the confluence of sinuses
where is the transverse sinus located
laterally from the confluence of sinuses in posterior margin of tentorium cerebelli; continuous with sigmoid sinus
location of the sigmoid sinus
continuation of the transverse sinus. after it passes through the jugular foramina it is then the internal jugular vein
where is the cavernous sinus located
bilaterally on sides of sella turcica on the body of the sphenoid bone
four parts of the internal carotid artery (superior to inferior)
cerebral part
cavernous part
petrous part
cervical part
where do the vertebral arteries arise from
in the neck from the subclavian arteries and ascend vertically in the neck passing through the transverse foramina of cervical vertebrae (C6-C1)
what do the vertebral arteries meet as
the basilar artery
what does the basilar artery provide
posterior cerebral
branches to brainstem
superior cerebellar
anterior inferior cerebellar
what are the posterior communicating arteries
small arteries that provide a link between the posterior cerebral arteries and internal carotid arteries
what does the internal carotid artery provide
middle cerebral
anterior cerebral
what do the anterior communicating arteries connect
connects both anterior cerebral arteries
