Extracranial Cerebrovascular

Question 1

What’s the typical pressure of the arterial system?

Answer 1

80-100mmHg

Question 2

How much blood does the ICA get from the CCA?

Answer 2

70-80%

Question 3

ICA brings blood to what portions of the brain?

Answer 3

Anterior and middle

Question 4

What brings blood to the posterior portion of the brain?

Answer 4

Vertebrals (join together to become the basilar a)

Question 5

8 branches of the ECA:

Answer 5

Superior thyroid
Asc pharyngeal
Lingual
Facial 
Occipital
Posterior auricular
Maxillary
Superficial temporal

Seven angry ladies fighting over PMS

Question 6

Vertebrals come off which vessel?

Answer 6

Subclavian

Question 7

What are TIA’s most often caused by?

Answer 7

An embolic event where a clot or other debris (plaque) gets lodged in the cerebral vessels causing a temporary interruption of blood flow
Common origins are *Heart and carotids

Question 8

Does a RIND or TIA last longer?

Answer 8

RIND >24hrs– but the symptoms also completely resolve

Question 9

Plaque is composed of lipids known as

Answer 9

Fatty streaks

Question 10

Ulcerative plaque

Answer 10

Complete loss of the vascular endothelium. Considered unstable and a risk of emboli

Question 11

What conditions cause the heart to be the most common origin of an emboli?

Answer 11

Atrial fib, LV dysfunction and paradoxical emboli

Question 12

On sonographic evaluation of the carotids, you see a hypoechoic structure by the bulb. It is hypervascular. What is it? What would be the patients symptoms?

Answer 12

Carotid bulb tumor – vascular because it receives it’s blood supply from the ECA.
Difficulty swallowing and a large pulsatile mass

Question 13

What’s the difference between atherosclerosis and FMD?

Answer 13

Athero affects prox segments of the arteries, FMD affects the middle & dst segments
FMD affects young women and the renal and carotid arteries

Question 14

FMD is best seen by what modality? What does it appear as

Answer 14

Angiography – string of beads

Question 15

What is neointimal hyperplasia caused by?

Answer 15

Surgical intervention – can result in a hemodynamically significant stenosis or occlusion and is the main reason for restenosis within the first 2yrs

Question 16

What causes a dissection

Answer 16

Trauma

Question 17

An aneurysm is a focal dilation of an artery that is ____% greater than the diameter of it’s normal segment

Answer 17

50

Question 18

Where is the stenosis if the left vertebral has a reversal of flow?

Answer 18

Lt SCA

Question 19

Where is the most common location for a Subclavian Steal? Why?

Answer 19

Lt due to the origin off the aortic arch

Question 20

What drop in pressure do we see with subclavian steal?

Answer 20

15-20mmHg in the ipsilateral arm

Question 21

Symptoms of SSS?

Answer 21

Often asymtpomatic – however can see symptoms of verterobasilar insufficiency and may worsen w arm exercise

Question 22

What is the most important risk factor for stroke ?

Answer 22

Hypertension

Question 23

Hemiparesis

Answer 23

Weakness/paralysis

Question 24

Hemiparesthesia

Answer 24

Numbness, tingling, or loss of feeling

Question 25

What typically causes amaurosis fugax?

Answer 25

Often from an emboli in the opthalamic artery from the ipsilateral ICA

Question 26

What is hemianopia? What typically causes it?

Answer 26

Blindness in 1/2 of one or both eyes, typically caused by an occlusion of the MCA

Question 27

If someone has a symptom of anterior circulation issues, which vessels would be of concern?

Answer 27

ICA, MCA and ACA

Question 28

If someone has a symptom of posterior circulation issues, which vessels would be of concern?

Answer 28

VA, basilars, and PCA... if these are affected they will cause symptoms that will affect the body as a whole. Nonlateralizing

Question 29

Ataxia

Answer 29

A group of disorders that affect coordination, balance and speech

Question 30

What is another somewhat reliable way to screen for a carotid stenosis, other than duplex imaging?

Answer 30

Listening for a carotid bruit

Question 31

Where is the most common place for an occlusion to occur? During carotid US

Answer 31

ICA

Question 32

While scanning the carotid bulb, you notice there is some heterogenous plaque with anechoic areas within. What is the concern?

Answer 32

This most often represents an intraplaque hemorrhage. When this is seen, it's important to identify that the surface is intact and if it has a smooth or irregular surface. Irregular surfaces indicate that plaque has ruptured or ulceration, and is considered unstable

Question 33

What is latent steal:

Answer 33

When a subclavian steal hasn't manifested fully and there is alternating flow directions in systole and diastole

Question 34

Majority of carotid artery disease occurs within _____ of the ICA

Answer 34

2cm (this means usually the pre stenotic zone is in the CCA)

Question 35

If you see a loss of diastolic flow in the ipsilateral ICA, where would the stenosis be?

Answer 35

Intracranial ICA or MCA

Question 36

If you see that both left and right CCA's have a diminished waveform, where is the source of problem?

Answer 36

Heart

Question 37

What can help confirm the presence of a Lt ICA occlusion?

Answer 37

Loss of diastolic flow in the Rt CCA

Question 38

The ECA has a velocity of 134cm/s, and a ratio of 3. What grade of stenosis?

Answer 38

N/A. The grading system cannot be used on vessels other than the ICA

Question 39

A patient gets a CEA and within two years it is restenosed. What is the issue?

Answer 39

Would not be plaque, likely would be neointimal hyperplasia

Question 40

What would one expect to see in a patient with a stent?

Answer 40

Increased velocities

Question 41

What's the first branch off the ICA?

Answer 41

Opthalamic (happens intracranially)

Question 42

The first branch of the thoracic aortic arch?

Answer 42

Innominate

Question 43

Which of the following lesions is most likely to cause a subclavian steal syndrome? (A) Innominate artery stenosis (B) Left proximal subclavian artery stenosis (C) Left distal subclavian artery stenosis (D) Both A and B

Answer 43

D-- Both an innominate artery and proximal left subclavian artery stenosis are likely to cause a subclavian steal syndrome because they would be proximal to the origin of the vertebral arteries. A stenosis in the distal left subclavian artery would be past the origin of the vertebral artery thus not resulting in a steal.

Question 44

A 75-year-old man is scheduled for a carotid duplex and presents with symptoms of complete loss of mobility in the left arm. In which vessel would you most likely find disease? (A) Left internal carotid artery (B) Left common carotid artery (C) Right internal carotid artery (D) Right vertebral artery

Answer 44

C-- Complete loss of mobility on one side of the body is a lateralizing symptom that is associated with ICA disease

Question 45

The pressure gradient across a stenotic segment as it increases from a 50% narrowing to a 90% narrowing (A) Decreases (B) Does not change (C) Is unaffected (D) Increases

Answer 45

(D) A pressure gradient refers to the difference between two pressures, in this case, the pressure proximal and distal to the stenosis. As a stenosis increases from a 50% narrowing to a 90% narrowing the distal pressure will decrease even more resulting in an increased difference between pressures.

Question 46

All of the following are lateralizing symptoms caused by a disturbance of blood flow to the contralateral hemisphere EXCEPT (A) Hemiparalysis (B) Amaurosis fugax (C) Hemiparesthesia (D) Aphasia

Answer 46

Amaurosis fugax is the only lateralizing symptom not caused by disturbance to blood flow on the contralateral side of the body. It is caused by emboli traveling through the ipsilateral ICA to the ophthalmic artery resulting in a temporary loss of vision.