Carotid Stenosis

Preliminary Diagnosis: Carotid Stenosis

I. What imaging technique is first-line for this diagnosis?

• Ultrasound with Doppler interrogation and spectral waveform imaging

II. Describe the advantages and disadvantages of this technique for diagnosis of carotid stenosis.

Advantages

• Relatively inexpensive

• Does not use ionizing radiation

• Can compare both left and right carotid vasculature

• Useful for detecting low velocity flow at and distal to preocclusive stenoses

• Useful for estimating degree of stenosis with velocity parameters

Disadvantages

• May be difficult to examine vasculature in obese patients

III. What are the contraindications for the first-line imaging technique?

No significant contraindications

IV. What alternative imaging techniques are available?

• MRA

• Digital subtraction angiography (DSA)

V. Describe the advantages and disadvantages of the alternative techniques for diagnosis of carotid stenosis.

MRA

Advantages

• Does not expose the patient to ionizing radiation

Disadvantages

• Expensive

• Requires significant patient cooperation to minimize motion artifact

• May over or underestimate the degre of carotid stenosis due to flow turbulence

DSA

Advantages

• It is the gold standard for documentation of carotid stenosis/occlusion.

Disadavantages

• Expensive

• Exposure to ionizing radiation

• Invasive

• May underestimate the degree of stenosis

VI. What are the contraindications for the alternative imaging techniques?

MRA

Absolute contraindication is non-MR-compatible hadware.

DSA

Relative contraindication is exposure to ionizing radiation in pregnant patients.