brain circulation Flashcards
entry of internal carotid
carotid canal
where does the ICA passes
anteriorly and medially through the cavernous sinus of the sphenoid body
what are the terminal branches of ICA
Anterior cerebral a.
• anterior communicating artery • Middle cerebral a.
where does the vertebral a. pass through
Pass through the transverse foramina of the first 6 cervical vertebraePerforate dura and arachnoid to pass through the foramen magnum
where does the vertebral a. unit
Unite anterior to pons to form the basilar artery
which martial system isalso know as the posterior circulation of the brain
vertebrobasilar
which artery lies close to the base of the skull
basilar
basilar a. divided into
Divides into the (2) posterior cerebral arteries
the post. cerebral a. join with which artery
join the internal carotid artery (ICA) via the posterior communicating arteries
what does the ant cerebral a. supplie
Supplies most of the medial and superior surfaces of the
brain and frontal pole
what does the middle cerebral a. supplies
Supplies the lateral surface of the brain and temporal pole
what does the posterior cerebral a. supplies
Supplies the inferior surface of the brain and occipital pole
role of circle of Willis
Important anastomosis at the base of the brain
which veins is the principle vessel to receive blood from the venous sinus of dura matter
internal jugular vein
what those the vein in the brain supplies
Veins draining the brain are tributaries of the large venous sinuses in the dura mater
what happens if the jugular become occluded
the angular vein, pterygoid plexus and suboccipital veins offer collateral circulation
what is the dural venous sinus
Endothelium lined spaces between the periosteal and meningeal layers of the dura
where those the large veins from the surface of the brain empty
into dural venous sinuses where they drain all the blood into internal jugular vein
which veins liesin the superior border of the falx cerebri
sup sagittal sinus
location of sup sagittal sinus
Lies in the superior border of the falx cerebri
• Originates at the crista galli and ends near the internal
occipital protuberance at the junction of the confluence of sinuses
what empty into the confluence of sinuses
sup sagittal sinus, straight sinus, occipital sinus, transverse sinus
location of inf sagittal sinus
Runs in the inferior border of the falx Cerebri and terminates in the straight sinus
what formed the straight sinus
the joining of the Inferior Sagittal Sinus and the Great Cerebral Vein
location of straight sinus
Runs infero-posteriorly along the line of attachment of the falx Cerebri and the Tentorium Cerebelli
pathway of transverse sinus
Leaves the confluence of sinuses laterally along the occipital bones and the posteroinferior angles of the parietal bones
which veins becomebecome the sigmoid sinus as they approach the petrous portion of the temporal bones
transverse sinus
which one btw right of left transverse sinus is larger
right
which veinsFollows an S-shaped course in the posterior cranial fossa
sigmoid sinus
which veins form deepgrooves in the temporal and occipital bones
sigmoid sinus
pathway of sigmoid sinus
Continues inferiorly to the jugular foramen to become the internal jugular vein
location of sigmoid sinus
posterior cranial fossa
location of cavernous sinus
middle cranial fossa, on each side of sella turcica
which veins is located on each side of sella turcica
cavernous sinus
pathway of cavernous sinus
extends from the superior orbital fissure anteriorly to the apex of the petrous portion of the temporal bone posteriorly
cavernous sinus receive blood from and where does it drain it blood
- sup. Ophthalmic vein
- inf. Ophthalmic vein
- Middle cerebral vein
- Sphenoparietal sinus
Will drain to the superior and inferior petrosal sinus (postero-inferiorly) and to the pterygoid plexus
what is content in the cavernous sinus
- Internal carotid artery
* Carotid plexus of sympathetic nerves • Abducens nerve (CVI)
what is ensheted in lateral wall of cavernous sinus
- Occulomotor nv. ( III)
- Trochlear nv. (CIV)
- Trigeminal nv. (CV1 and sometimes CV2)
pathway of superior petrosal sinus
Run from the posterior ends of the veins of the cavernous sinus to the transverse sinus to then curve to form the sigmoid sinus
location of sup petrosal sinus
anterolateral portion of the tentorium cerebelli,Attaches to the petrous portion of the temporal bone
which veins attached to the petrous portion
sup petrosal sinus
pathway of inf petrosal sinus
Also begins at the posterior ends of the veins of the cavernous sinus inferiorly
• Runs between the petrous portion of the temporal bones and the basilar portion of the occipital bone
drainage of inf petrosal sinus
Drains the lateral cavernous sinus directly into the origin of the IJV
what does the basilar plexus connect
Connects inferior petrosal sinus to internal vertebral venous
network
what does the emissary veins connect
Connect dural venous sinuses with veins outside the cranium
what is the arachnoid granulation
Collection of arachnoid villi
• Prolongation of arachnoid that protrude through the meningeal layer of the dura into the dural venous sinuses
location of arachnoid granulation
found in areas of the sup sagittal and transverse sinus
what does the arachnoid granulation affect and function
- affect the transfer of CSF to the venous system
- Are structurally adapted to transport CSF from the subarachnoid space to the venous system
