Lesson 16 - Vertebral Pathology

Question 1

When imaging the vertebral artery it is imporant to include ________ in your image

Answer 1

Transverse Processes of the vertebrae

So people will believe it’s the vertebral artery

Question 2

Where is the doppler beam sent when imaging the Vertebral Artery?

Answer 2

Between the transverse processes

Question 3

Imaging techniques for a normal vertebral artery

Answer 3

• Anterior window
• line up on mid to distal CCA
• Angle lateral and look for shadow (angle & tip)
• Velocity - PSV (EDV optional)
• Waveform morphology
• Direction, ex: waveform is inverted above the baseline, going away from the TD, toward the head, correct for vertebral
• Sometimes straight steer of color and/or spectral works better btwn small disc space
• Some machines have alternate 20deg angle rather than 30
• Check direction with spectral – may be vertebral vein too
• Vertebral vein may be pulsatile

Question 4

Where is the obstruction when a Lt. Vertebral steal occurs?

Answer 4

Lt. Subclavian proximal to vertebral

• Reversed flow in ipsilateral vertebral
• Increased velocity in contralateral vertebral

Question 5

How does the disease progress in Lt. Vertebral Steal?

Answer 5

• Early systolic deceleration
• Partial steal (incomplete, transitional, to & fro)
• Complete steal

*More steal when arms are in use

Question 6

Describe the waveform changes with advancing vertebral and subclavian steal

Answer 6

NORMAL: continuous forward flow

EARLY STEAL: peak begins to invert during systole

PROGRESSION OF SUBCLAVIAN DISEASE: increasing systolic peak inversion until the peak reverses below the baseline. To and fro patterns are seen when the systolic peak falls below the baseline while the diastolic flow continues in the forward direction.

FINAL STAGES: entire waveform shows continuous flow reversal

Question 7

Describe the waveform of an early subclavian steal

Answer 7

• Continuous forward flow
• Systolic peak inversion

*mild steal = mild occlusion

Question 8

What is an early sign of subclavian stenosis?

Answer 8

Early systolic deceleration (ESD) after peak systole

Question 9

What is the “bunny rabbit”?

Answer 9

Early Systolic Deceleration (ESD)

• happens in the vertebral on the side of the occluded subclavian
• changing pressure patterns in left arm in the presence of proximal subclavian srtery stenosis affect the vertebral waveforms

Question 10

What exacerbates ESD?

Answer 10

progression of subclavian disease

Question 11

What is the stress study?

When is it done?

Answer 11

1. Stress pts effected arm to increase perfusion
2. when partial steal is detected

Question 12

How is a stress study performed?

Answer 12

1) Isometric exercise, doppler while doing it and you’ll see full reversal start (using arms may turn partial steal into severe) *look at diseased arm
2) Inflate cuff above systolic pressure for 2-3 minutes (causes vasodialtion)
3) Doppler upon release of cuff and you’ll see full reversal

*flow will be normal when cuff is inflated b/c no blood is getting to the arm - will reverse when cuff is released. **same side as subclavian. as it get’s worse, you lose the bunnies ear

Question 13

What is done during the isometric exercise of the stress study?

Answer 13

Pt clench fist for 3 seconds

Upon release of fist the flow will reverse

Question 14

What happens to the flow in the vertebral when the pt clenches and releases fist?

Answer 14

flow will reverse upon release of fist

Question 15

Retrograde flow in the vertebral artery throughout systole and diastole is a sign of _______________

Answer 15

Severe subclavian stenosis or occlusion

*flow towards the arm the entire time

*complete steal

Question 16

Rt. vertebral steal is a sign of occlusion in the ________

Answer 16

Innominate/Brachiocephalic

*typically brachiocephalic that is reversed so you may get reversal of vetebral and maybe even carotid

Question 17

How are the rt subclavian and rt CCA fed in the case of an Innominate stenosis?

Answer 17

reversal on right vertebral flow

Question 18

What is a cause for retrograde flow of the Rt. CCA?

Answer 18

Innominate/ Brachiocephalic stenosis

aka: Carotid steal

Question 19

Slow upstroke and low resistance waveform is a sign of _______________________

Answer 19

proximal stenosis

Question 20

20 mmHg difference between the R & L brachial pressures suggests ___________

Answer 20

subclavian stenosis

Question 21

What is often the first indicator of subclavian artery disease?

Answer 21

a change in the morphology of the vertebral artery waveform (bunny)

Question 22

What chages first with subclavian disease?

• pressue gradiant >20mmHg between R & L

OR

• change in morphology of the vertebral artery waveform

Answer 22

change in morphology of the vertebral artery waveform

Question 23

Describe the waveform of a normal subclavian artery

Answer 23

• rapid upstroke
• minor dicrotic notch
• continuous flow

Question 24

Describe an abnormal subclavian artery distal to stenosis

Answer 24

slow acceleration time, low velocity

Question 25

No flow = \_\_\_\_\_\_\_\_\_\_\_\_\_

Answer 25

proximal occlusion

Question 26

High resistance with normal acceleration time = \_\_\_\_\_\_\_\_\_\_\_\_\_\_

Answer 26

distal disease such as vertebral or basilar obstruction

Question 27

Compensatory flow for other disease can _______ veloctiy

Answer 27

increase, moderately high

Question 28

Very high velocity is a sign of \_\_\_\_\_\_\_\_

Answer 28

stenosis

Question 29

If there is no flow detected in the vertebral, first be sure \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_

Answer 29

beam is not blocked byt the vertebrae

Question 30

High resistance flow pattern of the vertebral is most likely due to \_\_\_\_\_\_\_\_\_\_\_\_

Answer 30

distal vertebral or basilar obsturction

Question 31

Describe the vertebral flow chart

Answer 31

\*Insert chart\*

Question 32

Use the \_\_\_\_\_\_\_\_\_\_\_window when imaging the vertebral

Answer 32

anterior

Question 33

what does a waveform look like in a stenosis?

Answer 33

turbulent, quick acceleration, spectral boradening.

Question 34

Which of the following instrument adjustments is often required when imaging the vertebral artery due to the depth of the vesse increase Doppler gain increase Doppler frequency increase Doppler beam steering increase Doppler scale

Answer 34

increase doppler gain

Question 35

Retrograde flow in the vertebral artery is associated with stenosis of the contralateral subclavian artery proximal to the vertebral branch contralateral subclavian artery distal to the vertebral branch ipsilateral subclavian artery proximal to the vertebral branch ipsilateral subclavian artery distal to the vertebral branch

Answer 35

ipsilateral subclavian artery proximal to the vertebral branch

Question 36

What does this vertebral waveform represent? to & fro pattern with antegrade flow in systole and retrograde flow in diastole to & fro pattern with retrograde flow in systole and antegrade flow in diastole retrograde flow in a full subclavian steal tardus parvus associated with proximal vertebral stenosis

Answer 36

to & fro pattern with retrograde flow in systole and antegrade flow in diastole

Question 37

What additional findings would you expect after identifying this waveform of the left vertebral? retrograde CCA flow on the left decreased brachial artery blood pressure on the right retrograde CCA flow on the right decreased brachial artery blood pressure on the left

Answer 37

decreased brachial artery bp on lt

Question 38

What does this distal subclavian waveform represent? normal subclavian flow to & fro pattern associated with subclavian steal syndrome to & fro pattern associated with vertebral stenosis tardus parvus associated with proximal subclavian stenosis

Answer 38

tardus parvus assoc w/ proximal subclavian stenosis