Relationship between carotid plaque surface morphology and perfusion: a 3D DCE-MRI study

Area of Science:

• Cardiovascular Imaging
• Medical Physics
• Radiology

Background:

• Carotid artery plaque morphology is a key determinant of stroke risk.
• Neovascularization within plaques is associated with plaque instability and rupture.
• Current imaging techniques may not adequately capture the relationship between plaque surface characteristics and neovascularization.

Purpose of the Study:

• To investigate the association between carotid plaque surface morphology and neovascularization.
• To evaluate the feasibility of using a single 4D contrast-enhanced MRI/MRA sequence for simultaneous assessment of plaque morphology and neovascularization.

Main Methods:

• A high temporal and spatial resolution 4D contrast-enhanced MRI/MRA sequence was employed.
• Twenty-one patients with symptomatic or ≥40% carotid stenosis were included.
• Plaque surface morphology and stenosis were assessed. Neovascularization was quantified using pharmacokinetic (PK) modeling, calculating K^trans and v_p in plaque and adventitia.

Main Results:

• Image acquisition was successful in 28 arteries with a mean stenosis of 44%.
• Ulcerated/irregular plaques showed significantly higher adventitial and plaque K^trans compared to smooth plaques (p < 0.05).
• Adventitial K^trans and v_p positively correlated with the degree of stenosis (r = 0.44, p = 0.02; r = 0.55, p = 0.01).

Conclusions:

• A single 4D CE-MRA/DCE-MRI sequence can effectively evaluate carotid plaque morphology and neovascularization.
• Significant relationships exist between carotid plaque surface morphology and neovascularization.
• These findings highlight the potential of advanced MRI techniques for assessing plaque vulnerability.