Unit 18: Peri-operative and carotid stent duplex

Question 1

What are a few carotid disease treatment options?

Answer 1

• Medication
• Stent
• Surgery

Question 2

What are a few examples of medication options?

Answer 2

• Anti-platelet drugs
• Anticoagulant
• Control risk factors

Question 3

What what the 4 areas you scan peri-treatment?

Answer 3

1. Pre-op
2. Intraop
3. Post-op
4. Stent

Question 4

What should you note in a pre-op carotid exam?

Answer 4

• Quality of image
• High or low bifurcation
• End of plaque visualized
• All data agree
• If calcifcation obscures tightest point of stenosis.

Question 5

What should you note in a Intraop carotid exam?

Answer 5

• If there is a precense of a thrombus
• If there is an increased velocity? (2x)
• If there are fronds presence

Question 6

What should you note in a post-op carotid exam WITHOUT no patch?

Answer 6

• Note shelf in CCA at proximal end of CEA in early images
• Expect flow disturbances past shelf-may become less pronounced over time. (remodeling)
• Suture lines best seen in AP view
• Flaps of tissue seen early that reattach over time
• Dramatic curvature at end of CEA with tight Doppler angles increasing velocities.

Question 7

What should you note in a post-op carotid exam WITH patch?

Answer 7

• Note the patch used to avoid decreased diameter with restenosis.
  
  • vein or prosthetic

Question 8

Where is a patch usually used?

Answer 8

Usually mid/distal CCA into ICA

Question 9

What is usually seen with a dacron or PTFE patch?

Answer 9

Air may cause shadowing within 48 hours.

Question 10

What kind of flow is seen in a patch area?

Answer 10

Flow disturbances.

Question 11

What type of velocities are seen in a widened areas?

Answer 11

Low velocities are seen well after surgery, may be high immediately post.

Question 12

How should you scan carotid stents?

Answer 12

Scan:

• Proximal to stent (inflow)
• 3 velocities within stent
• Distal to stent (outflow)

Question 13

Stents have a tendency to yield _____ velocities than native arteries.

Answer 13

Higher.

Question 14

What do you want to be sure to document when scanning a carotid stent?

Answer 14

Be sure to document B-mode to demonstrate intrastent plaque or intimal hyperplasia vs extrastent residual plaque.

Question 15

What is important to visualize in a carotid stent?

Answer 15

Important to visualize substances either inside or outside the stent walls.

Question 16

What is the typical cause for post-CEA disease/stenosis?

Answer 16

Intimal hyperplasia.

Question 17

Does no specific changes in velocity indicate a significant change?

Answer 17

Yes, it is known to be significant on its own.

Take each tool into account: velocity, ratio, image.