13: Blood Supply In The Brain Flashcards
Vertebral A vs ICA % of blood to brain
Vertebrals: 20%
ICAs: 80%
What does the ICA bifurcate into?
ACA + MCA
Where are all the major vessels of the brain found?
Subarachnoid space
What is the space called surrounding the major vessels of the brain
Perivascular space (Virchow-Robin space)
Four arteries in the circle of Willis
ACA, PCA, ACoA, PCoA
Completeness of circle of Willis
Complete and symmetric in only 20% of people
Hypoplasticity of circle of Willis
PCoA, ACoA, and right vertebral A may be hypoplastic -> unaffected portion can hyperperfuse the affected circulation, can cause ischemia or cerebral edema
Watershed region of cerebrum
Border-zone regions supplied by major cerebral A’s
ACA location
Next to CN 1 and 2
Damage to Wernicke’s region
Pts talkative, but lack content or meaning in spoken and written language
Basilar A flow direction
Blood can flow anterior posterior depending on pressure differences
Terminal branches of the basilar A
PCA’s
Location of SCA
Just posterior to CN 3
Location of AICA
In the pontobulbar sulcus near CN 6, 7, and 8
Superficial middle cerebral V location
Lateral fissure
Internal cerebral V location
Next to parahippocampal gyrus
What do the thalamostriate and anterior septal veins drain?
Thalamostriate: corpus striatum
Anterior septal veins: septal area of limbic lobe
Basal vein of Rosenthal location
Next to cerebral peduncle
What do the middle deep cerebral and anterior cerebral veins drain?
Middle deep cerebral: insula
Anterior cerebral: frontal lobe
Great vein of Galen location
Next to posterior corpus callosum
Obstruction of great vein of Galen
Usually fatal
Venous varix of great vein of Galen
Dilation, can compress pineal body and posterior commissure
Thrombosis of the superior sagittal sinus
Causes cortical ischemia
Thrombosis of straight sinus
Causes ischemia of deep cerebrum, is usually fatal
