Spinal Arterial Circulation Flashcards
Exam 3
75% of spinal cord perfusion comes from which artery?
Anterior Spinal artery
Spinal arteries have this similar function of cerebral arteries that allows them to maintain consistent blood flow despite changing systemic blood pressure.
Autoregulation
What is the name of the radicular artery that provides 2/3 perfusion to the lower portion of the cord.
Great Radicular Artery (GRA)/ “Artery of Adamkiewicz”
Which side of the body is the GRA most likely to branch
Likely from the left side because that’s where the aorta is located
The posterior spinal arteries combine contribute ____% of cord tissue perfusion
25%
Loss of blood flow to which spinal artery would be the worst
Anterior spinal artery- 75% of perfusion
Where does the anterior spinal artery lie
Lies in the anterior median fissure
Which vertebrae is the GRA branching most common
T10
T9-12 (75% of population), can be as high as T5 or low as L5
How many posterior spinal arteries do we have
2
Which arteries can feed into the posterior spinal arteries?
Vertebral arteries, Cerebellar (anteriorinferior or posteriorinferior), Radicular/Posterior segmental medullary artery via intercostal arteries
What is another name for radicular artery
“medullary” or “segmental”
What is the downside to clamping the aorta during procedures
inhibiting blood flow to the spinal cord - higher radicular artery = safer
Where do radicular arteries feed from?
intercostal artery
What could occur if a clamped aorta is unclamped too fast?
Ischemia reperfusion injury- sudden restoration of blood flow to tissue. Vessels wide open causing massive increase of blood flow that tissues can’t handle. Too much oxygen can cause damage to cells.
Spinal arteries lie within which spinal meninges?
subarachnoid space
Where do coronal arteries lie?
Smallest branches that lie on outer surface of the spinal cord
How much does clamping the aorta typically change CSF pressure?
clamping increases CSF pressure by ~10mmHg
may place lumbar drain to drain CSF to control pressure
What is the pathway of blood flow from the aorta to spinal cord
aorta -> intercostal -> dorsal branch -> spinal branch -> radicular (posterior or anterior) -> anterior or posterior spinal artery
What are ways to reduce cord ischemia if clamped for long period of time?
anything to reduce inflammation, reduce metabolic rate
What is different about the spinal arterial circulation from the brain?
The spinal circulation doesn’t have a circle of willis; there isn’t a connection between the anterior and posterior spinal arteries
What is the main difference between the arterial and venous circulation of the spine?
There is an extra posterior vein midline in addition to the two lateral posterior spinal veins
What are the arteries coming off the abdominal aorta on each side?
renal arteries and mesenteric arteries
In the neck, there are usually __ feed arteries that feed into the anterior spinal artery
2
In the thorax, there are usually __ feed arteries that feed into the anterior spinal artery
2-3
In the lumbar, there are usually __ feed arteries that feed into the anterior spinal artery
1-2
Cerebral perfusion pressure =
MAP - ICP
Normal cerebral perfusion pressure
50-150 mmHg
normal ICP
10 mmHg
