Week 5 - Lesson 2 (Part 1) Flashcards
Stenosis
The narrowing of the arterial lumen, causing a hemodynamically significant change in flow
What can a significant stenosis cause?
Collateralization
- if its progressive
Total occlusion
The complete blocking of flow within an arterial lumen
When does collateralization occur?
If occlusion is not a sudden occurrence as with an emboli lodging in a small lumen
Where does plaque commonly form?
At the common carotid bifurcation
- involves distal CCA, Prox ECA/bulb, Prox ICA
How can plaque be characterized? (5)
- Homogenous
- Soft
- Heterogenous
- Ulcerated
- Calcified
What needs to be evaluated with plaque? (6)
- Extent
- Location
- Surface contour
- Texture
- Assess degree of luminal stenosis
- Evaluate in both transverse and sagittal projections
What is the best way to evaluate and characterize plaque?
Gray scale US
What is considered abnormal intima thickness?
> 0.9mm
Homogenous plaque
Generally uniform echo pattern and smooth surface
- 80-85% of patients
What does calcified plaque produce?
Posterior acoustic shadowing
How does calcified plaque appear on US?
Very echogenic
Does calcified plaque occur in symptomatic or asymptomatic patients?
Asymptomatic
Heterogenous plaque (2)
- Complex echo pattern
- contains one or more sonolucent areas - Cauliflower calcification appearance
Ulcerated plaque (4)
- Focal depression or break in plaque surface
- Irregular border contour
- Emboli twinkle artifact
- Hard plaque in the proximal ICA
Fibromuscular Dysplasia
Abnormal growth of cells in vessel walls and causes areas of narrowing
Where does fibromuscular dysplasia occur?
In the distal portion of the ICA
Carotid pseudoaneurysm
Collection of blood that results from injuries
Where does carotid pseudoaneurysm occur?
Between the medial and extra layer of the tissue layers
Carotid/vertebral artery dissection
Intimal flap in the lumen of the vessel
Where does carotid/vertebral artery dissection occur?
Usually in the carotid artery
Takayasus
Inflammation of the vessel walls
- thick walls
Where is takayasus seen?
Chemo or addictions
Raynaud’s phenomenon
Condition where the blood flow reduces to the fingers and toes
What are 2 symptoms of Raynaud’s phenomenon?
- Discolouration
2. Painful
Where is carotid body tumour found?
At bifurcations
What is another term for carotid body tumour?
Paragangliomas
What does carotid body tumour cause?
Widening
Are carotid body tumour highly vascular?
Yes
Are carotid body tumour usually benign or malignant?
Benign
- 5-10% are malignant
Thoracic outlet syndrome
Compression of nerves, artery or veins that usually happen from the clavicle and the 1st rib
Endarterectomy
Surgical treatment for stenosis
- US pre and post this surgery
- incision in the artery and remove the intema or media layer
Carotid stenting
Go through the artery with a balloon and try to open it up and widen it
- treatment for narrowing
- artificial tube (stent)
