Background: Carotid plaque neovascularization (vasa vasorum [VV]) may be useful for detecting high-risk atherosclerotic plaques. Contrast-enhanced ultrasound (CEUS) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) are 2 commonly used techniques for imaging VV of the carotid plaque, yet the relationship between their measurements remains unknown.
Objectives: We aimed to blindly evaluate the correlation between CEUS and DCE-MRI in measuring carotid plaque VV.
Methods: We recruited subjects with asymptomatic carotid stenosis (≥50%). VV was graded by CEUS, based on richness of contrast signal, according to 3 different methods named CEUS_A, CEUS_B and CEUS_C on different point scales (the higher the values, the higher the estimated VV). A 3.0 T MRI scanner was used for VV quantification by DCE-MRI using gadolinium contrast kinetic modelling for computing the fractional plasma volume (vp) and transfer constant (Ktrans).
Results: The analysis included 30 patients. A significant correlation between CEUS and DCE-MRI findings was observed when CEUS_C was used for neovessel grading and DCE-MRI was used to determine adventitial (r = 0.460, p = 0.010) and plaque (r = 0.374, p = 0.042) Ktrans values. CEUS_B (r = 0.416, p = 0.022) and CEUS_C (r = 0.443, p = 0.014) grading showed a significant correlation with regard to the maximal Ktrans.
Conclusions: We found a positive but weak correlation and a moderate diagnostic agreement between neovessels as visually graded by CEUS and adventitial neovessels assessed by DCE-MRI Ktrans in carotid atherosclerosis. These findings may help in understanding how VV density, flow, and permeability influence in vivo measurements by CEUS and DCE-MRI as well as in selecting the most appropriate variables and imaging method in future research and potentially in clinical settings. Further confirmative studies are necessary to confirm our results.
Trial registration: ClinicalTrials.gov NCT02321410.
Keywords: Atherosclerosis; Carotid artery stenosis; Contrast enhanced ultrasound; Dynamic contrast-enhanced magnetic resonance imaging; Neovascularization.
© 2019 S. Karger AG, Basel.