Week 1: Lecture 4 - Blood supply to the brain Flashcards
What % of our oxygen is used by the brain?
20%
What are 4 possible causes of focal cerebral lesions?
- Vascular (most common)
- Tumour
- Abscess
- Hydrocephalous - excess CSF causes increased intracranial pressure
What is a TIA ?
transient ischaemic attack
-stroke that lasts less than 24 hrs
what is a stroke?
neurological deficit of vascular origin, lasting more than 24hrs
What is herniation?
occurs when brain tissue, blood and cerebrospinal fluid shifts from their normal position inside the skull
What are the two main pairs of arteries that surround the brain and what are they connected by?
- vertebral artery
- internal carotid artery
connected by the circle of willis at the base of brain
Which artery does the vertebral artery branch of?
subclavian
Which foramina do the vertebral arteries travel through to reach the base of the brainstem?
- ascend through the transverse foramen of the cervical vertebrae in the neck
- enter skull via foramen magnum
Vertebral arteries fuse at the base of the brainstem to form what artery?
basilar artery
Which artery is the internal carotid a branch of?
common carotid artery
How does the internal carotid artery enter the skull
via carotid canals
Before the vertebral artery ascends through the foramen magnum and fuses into the basilar artery, what branches does it give off?
- PICA (posterior inferior cerebellar artery)
- Anterior spinal artery
- posterior spinal arteries
- AICA (anterior inferior cerebellar artery)
What does the anterior spinal artery supply?
anterior aspect of spinal cord
What is the origin of the PICA?
is variable
-can be from the PICA or straight from vertebral
What are the numerous tiny branches of the basilar artery called? where are they located?
- pontine branches
- in the pon
What arteries branch off from the basilar artery?
- SCA - superior cerebella artery
- PCA - terminal branch of the basilar artery
What do the SCA and PCA supply?
SCA- superior cerebellum
PCA - posterior cerebellum
What does the AICA and PICA supply?
AICA - Anterior, inferior aspect of cerebellum
PICA - Posterior, inferior aspect of cerebellum
What are the 3 branches from the internal carotid?
- ACA (anterior cerebral)
- ICA (inferior cerebral)
- MCA (middle cerebral)