Part 2 Blood Supply to Brain

Brain supplied by:

1. …

2. …

3. both originate on ____ and ascend through ____

4. Brain receives approx __% of cardiac output

• Internal Carotid arteries

• Vertebral arteries (via Basilar)

• both originate on Subclavian artery ascend through cerv. vertebral foramina ( C6 through C1)

• Brain receives approximately 15% of cardiac output

▪ Anterior circulation to brain arrives via the ________

▪ Two ______ bifurcate into an _____ and _____ carotid artery

▪ Right common carotid arises from the _______. The trunk bifurcates into the right ___ and right ______

▪ Left common carotid arises directly from the _____

▪ Anterior circulation to brain arrives via the internal carotid arteries

▪ Two common carotids (CCA) bifurcate into an internal (ICA) and external (ECA) carotid a.

▪ Right common carotid arises from the brachio-cephalic trunk (artery). The trunk bifurcates into the right CCA and right subclavian a.

▪ Left common carotid arises directly from the Aortic arch

Cerebral Arterial Circle (circle of willis)

• (need to know these)******

A roughly pentagonal “circle” of vessels on ventral surface of brain at midbrain level

From anterior to posterior:

- Anterior communicating artery

- Anterior Cerebral arteries

-Middle cerebral arteries

-Internal Carotid arteries

-Posterior Communicating arteries

- Posterior Cerebral arteries

-Basilar artery

Middle cerebral artery (MCA)

• the most common infarction (tissue death due to occlusion) of the brain, most commonly affects by cerebrovascular accident (CVA)

Aphasia may result from ___ ____infartion

Left MCA (middle cerebral artery) infarction

• The left cerebral hemisphere is dominant for speech and
  language in more than 95% of right-handed individuals

Lenticulostriate branches of the middle cerebral artery

• supply the _____: groups of ____ that influence_____ as well as controlling movement through multiple pathways utilizing several ______

supply the Basal ganglia: groups of neurons that influence initiation of movement as well as controlling movement through multiple pathways utilizing
several neurotransmitters

Anterior Cerebral Artery (ACA)

• supplies region that controls _____of the _______

• The region receives _____input from the ______

• Initiation of _____ may also be affected

• ACA supplies the ______

  • Prefrontal cortex functions in __________

• supplies region that controls movement of the contralateral lower limb.

• The region receives sensory input from the contralateral lower limb.

• Initiation of speech may also be affected

• ACA supplies the prefrontal cortex

  • Prefrontal cortex functions in volition, motivation, and planning and organizing of complex behavior

PCA supplies inferior aspect of _______ and _________

PCA supplies inferior aspect of cerebral hemisphere and occipital lobe

• 5-10% of ischemic strokes involve PCA