Cerebrovascular Anatomy

Question 1

Brain supplied by

Answer 1

ICA’s and vertebrals

Question 2

Aortic arch

Answer 2

Brachiocephalic
Lt CCA
Lt Subclavian

Question 3

First brach of Aortic arch. Terminated at Rt CCA and Rt Subclavian at level of _______.

Answer 3

Brachiocephalic / Innominate Artery

Sternoclavicular joint

Question 4

Second branch of aortic arch. Terminates at ______.

Answer 4

Left CCA

Carotid bifurcation Lt ECA and Lt ICA

Question 5

3rd branch of aortic arch. Terminates at ________.

Answer 5

Left subclavian

Thoracic outlet

Question 6

Most common Arch variant

Answer 6

Sharing or close association between origin of brachiocephalic artery, with Lt CCA. Known as Bovine Arch.

Question 7

ICA

_____ resistant

Gives off _______ branch in the _______ bone.

First major branch is __________ artery.

Further off gives off ________

Terminates into _________ and __________

Answer 7

• Low resistant. No branches of ICA in neck region except with disease. Supples anterior brain, eyes, forehead, nose.
• Gives of caroticotympanic branch in the petrous bone.
• 1st major branch comes off = ophthalmic artery.
• Gives off posterior communicating arteries.
• Terminates into middle cerebral artery and the anterior cerebral artery.

Question 8

Ophthalmic artery

Originates at __________ _______

Answer 8

Carotid siphon (significant curve in ICA)

Question 9

ECA has _ branches

First branch? (Often seen in carotid US)

Answer 9

8 branches:

• Superior thyroid: 1st branch. (May also come off distal CCA.)
• Ascending pharyngeal
• Lingual
• Facial
• Occipital
• Posterior auricular
• Maxillary
• Superficial temporal

Question 10

ICA ve ECA

Answer 10

ICA usually larger, usually posterior. Low resistant waveform. Low pulsatility, high diastoli.

ECA has branches. High resistant waveform. Usually smaller and anterior. Temporal tap shows oscillations during diastoli when tapped. Pulsatile, low diastoli, large diacrotic notch.

Take distal CCA velocity 2cm below bulb for accurate ratio. Highest ICA / distal CCA

Question 11

Bulb may be seen in

Answer 11

Distal CCA or prox ICA

Question 12

• Posterior brain supplied by _______ arteries.
• Which arise from ________ arteries.
• And lie within ________ ________.
• At _________ level, Rt and Lt join together and form ______ artery.
• Enter skull through ______ ______.
• _____ usually larger.

Answer 12

• vertebral arteries
• arise from subclavian arteries
• lie within foramina transversarum.
• pontomedullary level, form basilar artery.
• entre skull through foramen magnum.
• left usually larger.

Question 13

Basilar arteries divide into ______. Supplies blood to posterior cranial cavities.

Answer 13

• posterior cerebral arteries

Question 14

Circle of Willis

Answer 14

Common source for aneurysms, not complete in everyone.

Anterior, middle, and posterior cerebral arteries. They are joined together by anterior and posterior communicating arteries.

Blood flows through communicating arteries only when served as collateral pathways. If there’s a hemodynamically significant stenosis at the extra cranial carotid circulation.

More than 50% of people have incomplete circle of Willis.

Question 15

Most common variation of circle of Willis

Answer 15

Absence or hypoplasia of 1 or both communicating arteries.