neuroanatomy - ventricles, meninges, and blood flow Flashcards
what are the layers of the scalp?
Skin
Connective tissue
Aponeurosis
Loose connective tissue
Periosteum
What layers are in the “scalp propre”
Skin, connective tissue, aponeurosis
what is function of aponeurosis on the skull
to prevent stretching of the scalp
what muscles does the skull aponeurosis contain?
frontalis and occipitalis
what is the function of the frontalis?
raising eyebrows
what is function of occipitalis?
retracting scalp
what is the combo of the frontalis and the occipitalis called?
occipitofrontalis
what layers are in the deep scalp?
Loose connective tissue amd periosteum
what is the function of the periosteum of the skull?
to be a metabolically supportive layers on the bones
what does the loose connective tissue contain?
emissary veins that provide pathway to cranial vault - dangerous because can lead to infections
what are meninges?
3 layers of tissue that protect and support the CNS
what are the layers of the meninges?
Dura Mater, Arachnoid Mater, Pia Mater (superficial –> deep)
where is the dura mater later
The dura mater layer is the most superficial layer of the meninges, it is thick and deep to the calvarium (skull cap)
what is the function of the dura mater?
The dura mater functions to enclose the dural venous sinuses
what is the function of the dural venous sinuses?
drain cranial vault
what folds does the dura mater form?
falx cerebri, tentorium cerebelli, and the falx cerebelli
what does the falx cerebri do?
splits left cerebral hemisphere from right cerebral hemisphere
what does the tentorium cerebelli do?
seperates cerebrum from the cerebellum?
what are the layers of the Dura Mater
periosteal layer (superficial to) maningeal layer
what does the falx cerebri attach to anteriorly?
the crista galli of the ethmoid bone
what is the function of the Dura Mater
form dural venous sinuses
what potential spaces does the Dura Mater give?
the epidural space (superficial to) subdural space
what does the perosteal layer of the dura mater go around?
edge of the skull
what doee the meningeal layer of the dura mater go around?
the spinal cord
where does the arachnoid mater sit?
deep to the dura mater and on the dura mater
what is the function of the arachnoid mater?
protect and anchor brain (also is involved in CSF metabolism)
where is the subarachnoid space?
btw the arachnoid and the pia
what is the function of the subarachnoid space?
to contain cerebral spinal fluid
what does CSF do?
help metabolically and physically support the brain
how does CSF metabolically support brain?
acting as an exchange medium
how does CSF physically support brain?
providing buoyancy and cushioning
what is the function of arachnoid granualation?
to drain CSF through the dura
what is function of the arachnoid tuberculae?
To support the arachnoid mater
where is the pia?
layer deep to the arachnoid tuberculae
what is the function of the pia
to closely cover cortical sulci and gyri providing protection and support
what space exists between the pia and the cortex
the subpial space - potential space
which spinal meninges cover the spinal nerve roots?
dura and arachnoid meninges
where to denticulate ligaments come from?
the pia meninge
how do denticulate ligaments lead to cord stability
they connect the pia to the dura
which spinal meninges cover the spinal nerve roots?
the dura and arachnoid meninges
what layers is the epidural space between?
the epidural space is above the dura mater - it is between the dura mater and the lining of the vertebral canal
what does the epidural space contain?
fat and venous plexuses
what layers is the subarachnoid space between?
the arachnoid mater and the pia mater
what does the subarachnoid space contain?
Cerebral spinal fluid
What layers is the subdural space between?
the dura mater and the arachnoid mater
what layers is the subpial space between?
it is beneath the pia mater
what do the subdural and subpial spaces have in common hat the subarachnoid and epidural spaces do not?
the subdural and subpial spaces are both potential spaces
what is the overall function of a ventricle?
ventricles are cavities within the brain responsible for deep cerebral spinal fluid flow
how many lateral ventricles do we have?
2
which portion of the brain are the lateral ventricles associated with?
telencephalon (front part of cerebrum)
what is the function of the atrium in the lateral ventricles?
to connect anterior horn with the atrium
what portion of the brain is the third ventricle associated with?
the diencephalon (thalamus and hypothalamus)
what is the interthalamic adhesion in the third ventricle?
band of tissue passing through a middle hole in the 3rd ventricle
what is the function of the cerebral aqueduct?
the cerebral aqueduct connects teh 3rd and 4th ventricle passing through midbrain and pons
what is the function of the fourth ventricle?
the foruth ventricle communicates with the subarachnoid space
what part of the brain is the fourth vetnricel associated with?
the myenlecephalon - more specifically the brain
foramina of Luschka is also known as
lateral apertures
foramina of megendie is also known as
median aperture
where does the central canal of the fourth ventricle go to?
the spinal cord
what does the fourth ventricle provide for the spinal cord?
metabolic support
what is CSF produced by
choroid plexus
what is the choroid plexus
collection of ependymal cells found on the walls of all 4 ventricles that produces CSF that flows into the ventricles
from the lateral ventricle, where does CSF flow into next?
interventricular foramen
from the inter-ventricular foramen where does CSF flow into next?
third ventricle
from the third ventricle where does CSF flow into next?
cerebral aqueduct
from the cerebral aqueduct where does CSF flow into next?
the fourth ventricle
where can the CSF flow to from the fourth ventricle
the subarachnoid space (foramina of Luschka or the Foramen of Magendie) OR the central canal
Where in the subarachnoid space would the CSF flow into?
cisterns in the subarachnoid space (small cavities in the subarachnoid space) THEN it would flow along outer cortices (layers) of the cerebrum and cerebellum
How does CSF leave the subarachnoid space?
through arachnoid granulations
Once CSF leaves the subarachnoid space - where does it end up next
ocne CSF goes through arachnoid granulations it will drain into dural venous sinuses
what do arachnoid granulations pierce through
dural venous sinuses
what drains through arachnoid granulations?
CSF
what is the overall flow of cerebral CSF?
choroid plexus, lateral ventricle, interventricular foramen, third ventricle, cerebral aqueduct, fourth ventricle, median/lateral apertures, subsarachnoid cisterns, bathing superficial brain, arachnoid granulations, dural venous sinuses
what is the overall flow of spinal CSF?
choroid plexus, lateral ventricle, interventricular formane, third ventricle, cerebral aqueduct, foruth ventricle, central canal
what are the 3 major branches off the Aorta?
brachiocephalic trunk, the left common carotid artery, and the left subclavian artery
what does the brachiocephalic trunk supply?
The right side
what does the left common carotid artery supply?
The brain
what does the left subclavian arteyr supply?
the left side
what does the brachiocephalic trunk bufurctae into?
right common carotid artery and the right subcalvian artery
what are the 4 major arteries that supply the brain?
the common carotid (which then becomes internal carotid) and the subcalvian (which then becomes vertebral artery)
what does the vertebral artery run through?
the vertebral foramina of cervicle vertebrae to the brain
what artery goes through the carotid canal of the occipital bone?
The internal carotid artery
what artery goes through the anterior portion of the foramen magnum
the vertebral artery
where does the basilar artery come from?
the left and right vertebral arteries
where does the basilar artery sit?
the basilar grove of the pons
what is the relation between the basilar artery and the pons?
the basilar artery gives off pontine arteries to supply the pons
What do the posterior cerebral arteries supply?
The posterior cerebral cortex according to their respective sides
what does the basilar artery bifurcate into?
The left and right posterior cerebral arteries
what is the circle of willis
anastomosis/connection of arteries providing major cerebral blood supply
anterirorly, what does the circle of willis contain
the anterior cerebral arteries connecting by the anterior communicating artery
posteriorly what des the circle of willis contain?
the basilar artery leading to the posterior cerebral arteries leading to the EITEHR their respective respective side of the cerebral cortex OR to the posterior communicating arteries
what does the internal carotid artery lead to?
either the anterior cerebral artery or the mdidle cerebral artery or the posterior communciiating artery
in the circle of willis, what is the internal carotid artery connetced to?
the middle cerebral artery, the anterior cerebral artery, and the posterior communicating artery
what do communication arteries provide?
connections btw arteries
what do the L and R vertebral arteries combine to make?
basilar artery
What is the purpose of the circle of willis?
the purpsoe of the cricle of willis is to maintain cerebral blood flow throughout the brain
what is the purpose of dural sinuses/
drain the inner structures of the cranial vault to the heart
where is the superiror mid-sagittal sinus?
int the falx cerebri
what is the drainage of the sinuses starting at superior saggital sinus
the superior saggital sinus drains into the confluence of sinuses which drains into the transverse sinuses which drains into the tentorium cerebelli where the transverse sinus becomes the sigmoid sinus as it exits. The sigmoid sinus then drains into the internal jugular vein
where does the transvese sinuses drain into
the transverse sinuses drain into the tentorium cerebelli where it becomes the sigmoid sinus
where does the sigmoid sinus drain into?
the internal jugular vein
what is the jugular bulb?
superior enlargement of the internal jugular vein
what is the function of the cavernous sinus?
drain the eye, part of the cerebral cortex, and pituitary gland
what pierces the cavernous sinus?
the internal carotid artery - this artery then exists the dura and contributes to the circle of willis
