CNS vasc Flashcards
Prior to terminating, however, each ICA gives off a .
posterior communicating artery
posterior communicating arteries project posteriorly to communicate with the
posterior cerebral artery (PCA).
two ant cerebral art are connected by an anastomosing branch called the
anterior communicating artery.
not part of circle of willis
middle cerebral artery
hip and down provided by
Anterior cerebral artery (ACA)
middle cerebral artery
supply rest of body other than LE
lenticulostriate arteries
given off by middle cerebral arteries as they course lateral
frequent site of stroke
lenticulostriate arteries
internal capsule and deep gray matter
lenticulostriate arteries
formed by tight junctions between the endothelial cells lining CNS capillaries
Blood Brain Barrier
limit the flow of substances from capillaries into the CNS
tight junctions of Blood brain barrier
hydrophilic substances such as amino acids and glucose and medications
cant cross bbb alone
need carrier
Lipid soluble molecules, such as ethanol, nicotine and caffeine
cross the BBB,
Intermediate meningeal layer
Arachnoid
Conforms to shape of brain …
does not dip into sulci
Delicate membrane
Arachnoid
Pia mater
Adheres to the brain, following all of its contours
Dura mater
External Periosteal Layer
Internal Meningeal Layer
Internal Meningeal Layer of dura mater
Dense fibrous connective tissue
External Periosteal Layer
Formed by the periosteum which adheres to the internal surface of skull
two largest dural reflections are
Falx cerebri
©Tentorium cerebelli
invaginates along the longitudinal fissure, between the two cerebral hemispheres
Falx cerebri
positioned between the occipital and temporal lobes - and- cerebellum
Tentorium cerebelli:
dural venous sinuses
Dural reflections
receive deoxygenated blood
conveys deoxygenated blood from cerebral veins to the internal jugular vein
dural venous sinus system
arrange
venous sinuses –> cerebral arteries capillaries –>internal jugular vein–> cerebral veins
cerebral arteries capillaries –> cerebral veins –> venous sinuses –> internal jugular vein
diff b/n Cerebral veins and dural venous sinuses
typical venous histology vs. dural spaces lined with endothelial cells
Potential space between cranium & periosteal layer of dura
Epidural space
Epidural hemorrhage/ hematoma
Most frequently occurs with trauma/skull fracture
Epidural hemorrhage/ hematoma
Laceration/ tearing of the meningeal artery and
Bleeding into the potential space between the cranium and periosteal layer of dura
the periosteal dura encloses the
meningeal vessels.
subdural space
Potential space between the dura and arachnoid
Subdural Hemorrhage/ Hematoma
secondary to rapid acceleration/deceleration which pulls the brain away from the skull
tears cerebral veins as they enter the dural sinus
Subdural Hemorrhage/ Hematoma
subarachnoid space
true space that contains blood vessels and CSF
Interventricular Foramen (Foramen of Monroe)
communicates Lateral Ventricles (2) Right Left
to 3rd ventricle
communication between 3rd and 4th ventricle
Cerebral Aqueduct (Aqueduct of Sylvius)
Subarachnoid Hemorrhage/ Hematoma
arterial hemorrhage
Subarachnoid Hemorrhage/ Hematoma
~70% are 2° aneurysm
Foramen of Magendie
Midline opening in the 4th ventricle
Foramen of Luschka
Paired openings in the 4th ventricle
CSF is made in the —— ——-, it circulates through the ——— and exits the —- ventricle
CSF is made in the choroid plexus, it circulates through the ventricles and exits the 4th ventricle
As CSF leaves the 4th ventricle, it enters the
subarachnoid space.
CSF travel to subarachnoid space into the dural venous sinuses
via arachnoid granulations
