Cerebrovascular System Flashcards Preview

Neuroscience for the Study of Communication Disorders > Cerebrovascular System > Flashcards

Flashcards in Cerebrovascular System Deck (21)
Loading flashcards...
1
Q

Importance of CVS

A

Blood supplies brain with nutrition (glucose & oxygen)
Removes carbon dioxide from nerve cells
Brain requires constant and uninterrupted flow

Blood flow interruption:
5-8 seconds = unconsciousness
20-25 seconds = stop electrical activity in area
4-6 minutes = irreversible brain damage

2
Q

Vascular Basics

A

Arteries carry oxygenated blood to tissues/organs; Veins return depleted blood to heart/lungs
Capillaries perform O2/Co2 gas exchange in lungs (alveolar sacs)

Blood = oxygen supply; dependent upon respiration and circulatory system

3
Q

Vascular Systems in Brain

A

2 major blood suppliers to brain – carotid (outer) and vertebral (inner) arteries

Carotid: begins with the common carotid; divides into external and internal carotid

Internal carotid forms 2 cortical arteries; close to Broca’s area

  • Anterior Cerebral (ACA)
  • Middle Cerebral (MCA)

Vertebral Basilar: begins with vertebral artery and merges to form the basilar artery; will join the Circle of Willis
-Basilar splits into the two Posterior Cerebral Arteries (PCA); supplies deep tissues and occipital lobe

4
Q

Circle of Willis

A

Wreath-shaped circle on ventral side of brain; Cranial nerves wrapped in all these blood vessels

Connects the carotid and the vertebral-basilar systems

Equalizes the blood flow to both sides of the brain; the safety net (compensatory circulation); can make up for blockage to areas above the circle

However, 80% of strokes occur in the circle of Willis; a lot of pressure pushed thru circle opposite a blockage

5
Q

Frontal Lobe Blood Supply

A

Lateral Surface: Middle Cerebral Artery (MCA)
Medial Surface: Anterior Cerebral Artery (ACA)
Inferior Surface: Middle and Anterior Cerebral Arteries

Important Areas: Broca’s Area, pre-motor cortex

6
Q

Parietal Lobe Blood Supply

A

Lateral Surface: Middle Cerebral Artery (MCA)
Medial Surface: Anterior Cerebral Artery (ACA)

Important Areas: Primary Motor Cortex, Primary Sensory cortex

7
Q

Temporal Lobe Blood Supply

A

Lateral Surface: Middle Cerebral Artery (MCA)
Medial Surface: MCA, PCA, posterior communicating & anterior choroidal
Inferior Surface: Posterior Cerebral Artery

Important Areas: Wernicke’s Area, primary auditory cortex

8
Q

Occipital Lobe Blood Supply

A

Lateral Surface: Posterior Cerebral Artery
Medial Surface: Posterior Cerebral Artery

Important Areas: Primary visual cortex

9
Q

Types of strokes:

A

Ischemic/Thrombosis – blood clot, stopped bloodflow

Transient Ischemic Attack – similar to ischemic, transient (moving); clot develops but does not completely occlude; holds for a period but then breaks away; often a precursor to a larger stroke

Aneurysm – deformity of vessel; congenital or blockage; pressure causes bulging, ballooning effect; weakens the stretched walls, could lead to rupture; if massive, could be fatal

Hemorrhage –bleeding; caused by aneurysm, trauma (blunt force, penetrating), tumor growth

10
Q

Stroke Warning Signs

A

Sudden numbness or weakness of face, arm, or leg, especially on one side of the body

Sudden confusion, trouble speaking or understanding

Sudden trouble seeing in one or both eyes

Sudden trouble walking, dizziness, loss of balance or coordination

Sudden severe headache with no known cause

11
Q

Spinal Cord Blood Supply

A

Anterior and posterior spinal arteries branch off the vertibral artery to supply the spinal cord

12
Q

Thalamus Blood Supply

A

posteromedial, posterolateral, and choroidal

13
Q

Hypothalamus Blood Supply

A

anteromedial and posteromedial

14
Q

Caudate Nucleus Blood Supply

A

anterolateral, medial striate, and lenticulostriate

15
Q

Putamen Blood Supply

A

lenticulostriate, medial striate, and anterior choroidal

16
Q

Globus Pallidus Blood Supply

A

anterior choroidal

17
Q

Subthalamus Blood Supply

A

posteromedial

18
Q

Substantia Nigra Blood Supply

A

posteromedial

19
Q

Blood-Brain Barrier

A

Structural property of the CNS vessels formed by closely packed endothelial cells that restrict the passage of most substances to the brain; further aided by end feet of astrocytes outside the capillary

Only lipid soluable substances can cross the BBB; the BBB is not developed in infants

Aneurysm, meningitis, severe infection, sickle cell disease, congenital malformation, tumors, penetrating wounds can degrade the BBB

20
Q

Arteriosclerosis

A

Narrowing of arterial lumen owing to accumulation of lipids, fatty substances, and cholesterol along walls of blood vessels; also called atherosclerosis

Lumen – the opening in a blood vessel thru which blood flows; lined with endothelium cells which are tightly packed and control what goes in/out; muscles contract/expand

Blood pressure rises in response to plaque build-up

21
Q

Artervenous malformations (AVM)

A

Congenital vascular disorder – clump of extra venous growth; blood still flows through; higher risk for aneurysm

Smaller malformations may be surgically repaired; larger ones may not