Vesicles to Ventricles -CSF and Blood Supply Flashcards
Why is the brain so dependent upon a constant blood supply?
neurons lack glycogen
What forms the BBB?
astrocytes and endothelial cells
Where do the 2 main arterial blood supplies to the brain stem from?
the internal carotid and the vertebral arteries
The anterior circulation system arises from the ____ and supplies the _____.
internal carotid artery; anterior half of the brain and medial occipital lobe
The posterior circulation system arises from the _____ and supplies the ____.
vertebral arteries; brainstem, cerebellum, the medial occipital lobe, and the inferior temporal lobe
The _____ arises from the internal carotid artery and supplies the anterior half of the brain and medial occipital lobe.
anterior circulation system
The _____ arises from the vertebral arteries and supplies the brainstem, cerebellum, the medial occipital lobe, and the inferior temporal lobe.
posterior circulation system
What are the 2 major terminal branches of the internal carotid artery?
the anterior cerebral artery and the middle cerebral artery
What does the middle cerebral artery supply?
the frontal, parietal, and temporal lobes
What supplies the frontal, parietal, and temporal lobes?
the middle cerebral artery
What supplies the anterior two-thirds of the cerebral hemispheres and the orbital cortex?
the anterior cerebral artery
What does the anterior cerebral artery supply?
the anterior two-thirds of the cerebral hemispheres and the orbital cortex
At the level of the pons, the _____ fuse to form the basilar artery.
vertebral arteries
At the level of the pons, the vertebral arteries fuse to form the _____.
basilar artery
The posterior cerebral arteries supply the _____ and the _____.
medial face of the occipital lobe; inferior surface of the temporal lobe
The _____ supply the medial face of the occipital lobe and the inferior surface of the temporal lobe.
posterior cerebral arteries
The _____ give rise to the anterior and posterior spinal arteries.
vertebral arteries
The vertebral arteries give rise to the _____.
anterior and posterior spinal arteries
This artery branches off the vertebral artery, wraps around the medulla, and supplies most of the most caudal part of the cerebellum.
PICA
This artery branches off the basilar artery, wraps around the caudal pons, and supplies the more anterior portions of the inferior face of the cerebellum.
AICA
This artery branches off the basilar artery, wraps around the rostral pons, and enters the posterior fossa supply by the superior face of the cerebellum.
superior cerebellar artery (SCA)
What is the Circle of Willis?
the connection of the posterior and anterior circulations via a series of arteries
This is the connection of the posterior and anterior brain circulations via a series of arteries.
the Circle of Willis
What is the dura mater?
a leathery layer closely applied to the cranium; the deepest layer
What is the pia mater?
a single layer of cells covering the outside of the CNS; most superficial layer
This is a single layer of cells covering the outside of the CNS.
the pia mater
What is the arachnoid mater?
a loose, spongy layer btw the pia and dura
This is a loose, spongy layer btw the pia and dura.
the arachnoid mater
This is a leathery layer closely applied to the cranium; the deepest layer.
the dura mater
What are the ventricles?
fluid-filled spaces within the brain
These are the fluid-filled spaces within the brain.
the ventricles
What is the cerebral aqueduct?
the connection btw the third and fourth ventricles
This is the connection btw the third and fourth ventricles.
the cerebral aqueduct
What is the fourth ventricle connected to?
the cerebral aqueduct and the subarachnoid space (via three apertures)
What is ependymal?
a single layer of cells that lines the ventricles
This is a single layer of cells that lines the ventricles.
ependymal
The ventricles are filled with _____.
CSF
What produces CSF?
the choroid plexus
Where is most of the CSF found?
in the subarachnoid space
How much CSF is produced per day?
500mL (it’s replaced 4x/day)
CSF returns to the blood primarily via _____.
arachnoid granulations (villi)
Where are arachnoid granulations found?
lining the principle dural sinuses
What lines the principle dural sinuses?
arachnoid granulations (villi)
If there is a failure of reabsorption of CSF or if it cannot flow, ______ increases resulting in _____.
intracranial fluid pressure; hydrocephalus
If the flow of CSF is interrupted, a _____ results.
non-communicating hydrocephalus
If the CSF gets to subarachnoid space but isn’t reabsorbed properly, it is called ______.
communicating hydrocephalus
What is a communicating hydrocephalus?
when the CSF gets to subarachnoid space but isn’t reabsorbed properly
What is a non-communicating hydrocephalus?
when the flow of CSF is interrupted
What is a hydrocephalus?
a failure of reabsorption or flow of CSF
