Blood Supply of the Brain Flashcards
Which main Arteries provide the Blood Supply of the Brain?
1) Internal Carotid Artery 2) Vertebral Artery: -Comes from the Subclavian Artery - Becomes Basilar Artery thus we call it “VertebroBasilar system”.
Where are the Major Arteries found in the Brain?
The Major Arteries are found in the Sub-Arachnoid Space.
Explain the Path of the Vertebral Artery and how it ends up becoming the Basilar Artery.
- The Vertebral As will leave from the Subclavian and go up through the “Foramina of the Transverse process”.
2) Once it reaches the Foramen Magnum it penetrates the Dura Mater and Arachnoid Mater and moves medially.
3) At the PontoMedullary Junction they merge to form the Basilar A.
4) Then above the exit of the 3rd Cranial Nerve it splits into two Posterior Cerebral A which go behind the brain stem.
Name the Branches of the Vertebral Arteries.
1) Anterior Spinal A:
Two branches (one from each Vertebral Artery) go down the Anterior Median Fissure of the Spinal Cord.
2) Posterior Inferior Cerebellar A
3) Posterior Spinal A:
- Travels down Posterolateral sulcus.
Name the Branches of the Basilar Artery.
1) Anterior Inferior Cerebellar A
- Supplies Cerebellum, Medula and Pons.
2) Pontine Arteries
3) Labyrinthine A:
- Comes 85% from AICA and 15% from Basilar A. It goes foward then laterally and goes with the Facial Nerve and Vestibocochlear nerve through the Internal Acoustic Meatus to the Inner Ear.
4) Superior Cerebellar Artery
Name the parts of the Internal Carotid Artery and explain the Path of this Artery to the Brain.
There are three parts to the Internal Carotid.
1) Cervical Part:
- The ICA in this part is in the “Lateral Pharyngeal Space”.
2) Petrous Part:
- At the base of the Skull the ICA enters the “Carotid Canal.
- It then exits through the “Foramen Lacerum” and enters the Middle Cranial Fossa.
3) Cavernous Part
- In this part the ICA follows the Cavernous sinus, going to the Posterior Clinoid then to the Anterior Clinoid where it goes up piercing the Dura and Arachnoid matter.
- After it Bifuricates into the Anterior and Middle Cerebral A
Name the Branches of the ICA before Bifurication.
1) Opthalmic A:
- Travels to the Orbit via the Optic Canal.
2) Posterior Communicating A:
- Goes back and joins with the Posterior Cerebral A (PCA).
3) Anterior Choroidal A:
- Supplies the Choroid Plexus of the Lateral and Third Ventricle.
Describe the Path taken by the Anterior Cerebral A (ACA).
After the Bifurication of the ICA, the ACA travels forward then loops around the Genu of the Corpus Callosum.
Then travels in the Interhemisphere Fissure.
The ACAs are joint together by the Anterior Communicating A.
Draw the “Circle of Willis”
Name the Anastomosises between the ICA and VertebroBasilar Systems.
1) Posterior Communicating Branch:
2) Glomus Anastamosis:
- Between the Anterior Choroidal A (of the ICA) and the Posterior Lateral Choroid A (of PCA).
- Found in the Central part of the lateral ventricle.
Describe the Blood supply of the Internal Capsule.
1) branches of MCA
2) Heubners Recurrent A of ACA
3) Direct branches of ICA
4) Anterior Choroidal A
Describe the Blood supply of the Thalamus.
Mainly supplied by Branches from the PCA.
Describe the Blood supply of the Hypothalamus.
Anterior Part via ACA.
Posterior Part via PCA.
Describe the Blood supply of the Caudate Nucleus and Putamen.
1) Heubners Recurrent A of ACA
2) Anterior Choroidal A
3) Branches of MCA.
Describe the blood supply of the Medulla.
1) Anterior Spinal A
2) Posterior Spinal A
3) PICA
