Extra-cranial Duplex US Examination

Question 1

Transient Ischemic Attacks dont last longer than?

Answer 1

24 hours

Question 2

What are the four symptoms typically associated with carotid artery atherosclerosis?

Answer 2

1. TIA - mini stroke that doesn’t last longer than 24 hours
2. Reversible ischemic neurologic deficit (RIND) - symptoms are the same as a TIA but last between 24-72 hours
3. Amaurosis Fugax - temporary painless loss of vision in one or both eyes
4. Stroke

Question 3

What should your scale be set to in a carotid exam?

Answer 3

20-40 cm/s

Question 4

What artery are you “tapping” in the temporal tap to determine if you are imaging the ECA?

Answer 4

Superficial temporal artery

Question 5

What portion of what vessel is important in patients at risk for fibromuscular dysplasia?

Answer 5

Distal ICA

Question 6

What gland can be seen superficial to the distal ICA?

Answer 6

SMG

Question 7

What type of waveform is seen in the vertebral artery?

Answer 7

Low resistance as it supplies blood to the brain and eyes

Question 8

From the carotid artery, what transducer movement would be used to image the subclavian artery?

Answer 8

Inferior

Question 9

What type of waveform is seen in the subclavian artery?

Answer 9

High resistance as it supplies muscle and not the brain

Question 10

Arterial velocity measurements should be obtained using an angle of insonation of what range of degrees?

Answer 10

45-60 degrees

Question 11

Where in the carotid arteries does plaque generally form?

Answer 11

1. Carotid bifurcation in the distal CCA
2. Proximal ICA
3. Proximal ECA

Question 12

What abnormality is described as separation of the vessel layers?

Answer 12

Arterial dissection - creates a false lumen in which blood from the true lumen can flow

Question 13

What type of waveform shows a higher forward diastolic flow velocity?

Answer 13

Low resistance

Question 14

What type of waveform shows a lower diastolic flow velocity?

Answer 14

High resistance

Question 15

What percentage of blood from the CCA flows through the ICA?

Answer 15

70%

Question 16

Where are baroreceptors located in the carotid system?

Answer 16

Proximal ICA - helps control blood pressure

Question 17

What adjustment should be considered when imaging the vertebral arteries after the carotid?

Answer 17

Decrease the scale for slower flow

Question 18

What type of waveform is seen in the brachiocephalic artery?

Answer 18

High resistance flow - triphasic waveform

Question 19

In what arteries will may have severe stenosis in subclavian steal?

Answer 19

1. L subclavian
2. R brachiocephalic

Question 20

What kind of subclavian steal shows antegrade flow with a deep notch before systole?

Answer 20

Hesitant or latent - Stage 1

Question 21

What kind of subclavian steal has “to-and-fro” flow?

Answer 21

Bidirectional or alternating - Stage 2

Question 22

What kind of subclavian steal has fully retrograde flow?

Answer 22

Complete - Stage 3

Question 23

What type of colour doppler flow is seen that precedes a complete occlusion?

Answer 23

“String sign” or “trickle flow”

Question 24

Where are you most likely to see the “string sign” on colour doppler?

Answer 24

ICA

Question 25

A severe distal CCA obstruction with continued patency of the carotid bifurcation is often referred to what?

Answer 25

A choke lesion - flow may be reversed in the ECA to supply the ICA

Question 26

Doppler waveform with a ICA stenosis vs ICA occlusion? (hint: what may also be seen in the CCA)

Answer 26

ICA stenosis - CCA will also appear blunted and resistive ICA occlusion - CCA takes on features of patent ECA

Question 27

Where does stenosis of the vertebral artery generally occur?

Answer 27

Origin of the vessel from the subclavian artery

Question 28

What may be going on with the heart if the waveform appears dampened and has delayed acceleration if there is no stenosis?

Answer 28

Low cardiac output or poor EF

Question 29

In what cardiac consideration will you see with "pulsus bisferiens"? (when waveform has two prominent systolic peaks separated by a mid-systolic retraction)

Answer 29

Aortic valvular disease or hypertrophic cardiomyopathy

Question 30

What is the ratio used to classify disease of the ICA?

Answer 30

ICA (highest PSV from stenosis) /CCA (PSV in normal mid to distal segment)

Question 31

If there is significant stenosis in the origin of the CCA, what will the waveform be like in the distal CCA?

Answer 31

Dampened

Question 32

What would the velocity have to be in order to classify a CCA or ECA stenosis as a 50-99% stenosis?

Answer 32

200cm/s or greater

Question 33

How do we quantify a vertebral artery stenosis of 50% or greater?

Answer 33

V1 - maximum PSV in proximal vertebral artery / V2 - PSV from normal distal vertebral artery

Question 34

Symptoms of a TIA occur on what side of the body in relation to the affected carotid artery causing the symptoms?

Answer 34

Opposite side of the body from the TIA

Question 35

Symptoms of amaurosis fugax occurs on what side of the body in relation to the affected carotid artery?

Answer 35

The SAME side

Question 36

What transducer movement would you use to go from the CCA to the vertebral arteries?

Answer 36

Slide or angle the transducer posteriorly

Question 37

What transducer movement would you use to image the subclavian artery from the neck?

Answer 37

Angle inferiorly from the neck

Question 38

T or F? Direct intervention is not possible with a completely occluded ICA?

Answer 38

TRUE

Question 39

Doppler parameters are relatively inaccurate for subcategorizing stenoses of less than what percent in terms of diameter reduction?

Answer 39

50%

Question 40

T or F? ICA/CCA ratio is valid in the presence of any type of CCA disease?

Answer 40

FALSE: is not valid when disease is significant

Question 41

How do we identify a vertebral artery stenosis of 50% or greater?

Answer 41

1. Use V1 - pre-stenosis (max velocity) Use V2 - at stenosis (normal distal vertebral artery) Use V1/V2 ratio. Will be >2.2 if stenosis is present 2. A vertebral artery PSV of 150cm/s or greater

Question 42

What PSV in the vertebral artery is indicative of stenosis?

Answer 42

150cm/s or greater