Question

A 65-year-old male presented with history of TIA, transient right upper limb weakness, diagnosed to have bilateral carotid artery stenosis on colour doppler.
How would you assess the plaque morphology?

Hint:

In assessing plaque morphology, the key is to determine whether the plaque is stable or unstable, as unstable plaques are more prone to rupture and cause embolic events.

Answer 1

Step 1: Understanding plaque morphology.
Plaque morphology refers to the composition and structure of the plaques in the carotid arteries. The nature of the plaque (whether it is stable or unstable) can provide information on the risk of stroke or other complications. Stable plaques are more fibrous, while unstable plaques are more lipid-rich and prone to rupture.

Step 2: Assessment methods.
Plaque morphology can be evaluated through various imaging techniques, including:
1. Color Doppler ultrasound: Non-invasive and widely used to evaluate the degree of stenosis, as well as the characteristics of the plaque. Plaques that are echolucent (less reflective) may be lipid-rich, while echogenic plaques are often more fibrous and stable.
2. CT angiography: Provides a detailed view of the arterial walls and plaques, allowing for the assessment of plaque composition and the identification of any thrombus or ulceration.
3. MRI/MR angiography: High-resolution imaging that can assess plaque composition, distinguishing between fibrous and lipid-rich plaques. It is also useful for detecting intraplaque hemorrhage or ulceration.
4. Intravascular ultrasound (IVUS): Invasive but provides detailed imaging of the plaque structure, including the presence of calcifications, lipid core, and fibrous cap.

Step 3: Conclusion.
A combination of non-invasive imaging (such as Doppler ultrasound or MRI) and advanced methods (such as CT angiography or IVUS) can provide a comprehensive evaluation of the plaque morphology, which helps guide treatment decisions.