Brain protection and Blood supply to the brain Flashcards
What forms the circle of willis
The branches of the ICA and the vertebral arteries coming into the cranial cavity
Vertebral artier are a branch of what
The subclavian artery
What is the pathway of the vertebral artery to supply the brain
The vertebral artier pass through the transverse process of the cervical vertebra and enter the skull through the foramen magnum to supply the brain
What is the 4 branches of the internal carotid artery
Ophthalmic artery
Anterior cerebral artery
Middle cerebral artery
Posterior communicating artery
What connects the anterior cerebral artery
The anterior communicating artery
What do the vertebral arteries join together to form
The basilar artery
Where is the basil artery formed
On the ventral surface of the brain stem
When does the basilar artery end
At the level of the midbrain
What does the basilar artery divide to from
2 posterior cerebral arteries
What does the posterior cerebral arteries join with
the posterior communicating artery
What does the linkage of all the cerebral arteries create,
The circle of willis - a reservoir at the base of the brain
What is the clinical significance of the circle of willis
Always enough blood through resevioir to ensure different part of the brain gets blood supply, therefore brain won’t suffer as easily form ischaemia due to compensation of circle of willis
Where is a stroke likely to occur in the brain
Distal to the end of the circle of willis as arteries become end-arteries
What supplies the medial aspect of the cerebral hemisphere (excluding occipital lobe)
Anterior cerebral artery
What supplies the lateral aspect of the cerebral hemisphere
Middle cerebral artery
What supplies the inferior aspect of the cerebral hemisphere and occipital lobe
Posterior cerebral artery
What is the middle cerebral artery in direct contact with
The internal carotid arteyr
Where do venous sinuses lie
Between layers of dura matter - that cover the intermitter of the skull
The dura venous sinuses join together where
At the transverse sinus
Where does the transverse sinus drain into
The sigmoid sinus then the internal jugular vein
Where is the superior sagittal sinus found
In the upper boarder of the falx cerebri
Where is the inferior sagittal sinus found
Running below the lower boarder of the falx cerebra
What is the 4 folds of dura matter found in the cranial cavity
Falx cerebri
tentoreum cerebelli
Falx cerebelli
Diphragma sellae
What is found in the subdural space
Potential space which is transferred by blood vessels penetrating in to the CNS
What is features of pia matter
Vascularised and dips into the folds of the brain
What is the purpose of the blood brain barrier
Is a protective mechanism that helps maintain a stable environment for the brain and prevents harmful amino acids & ions present in the bloodstream and blood cells from entering the brain
What three features form the blood brain barrier
Tight endothelium junction
Thick basal lamia
Foot processes of astrocytes
Where is the blood brain barrier absent in the brain
In the cicrumventricular organs:
Part of the hypothalamus
Posterior pituitary
How does the blood brain barrier affect the delivery of drugs to the CNS
Drugs for the CNS have to either be lipid soluble or use suitable vectors
What makes up the menges of the brain
Dura matter
arachnoid matter
Pia matter
What dura fold surrounds the pituitary stalk
Diaphragma sellae
What dura fold separates the two cerebellar hemispheres
Falx cerebelli
What dura fold separates the right and left cerebral hemispheres
Falx cerebri
What does the dura fold of the tentorium cerebelli separate
occipital lobes and cerebellum
