A feasibility study of ultrasound B-mode and strain imaging for risk assessment of carotid atherosclerotic plaques validated by magnetic resonance imaging

Stroke is a leading cause of mortality worldwide. One of its main reasons is rupture of carotid atherosclerotic plaques. Conventional B-mode ultrasound images and Doppler/color flow measurements are mostly used to evaluate degree of carotid atherosclerotic stenosis. However, stenosis underestimates plaque vulnerability due to positive remodeling. In addition, studies have shown that traditional B-mode ultrasound has limited capability in characterizing vulnerability associated plaque compositional features, particularly intraplaque hemorrhage. In contrast, the correspondence between multi-contrast magnetic resonance imaging (MRI) features, including morphology and plaque compositions, and histology has been well established. In this study, the feasibility of B-mode image combined with strain image in composition characterization and risk assessment of carotid atherosclerotic plaques is investigated. Preliminarily in-vivo results on a small number of human subjects are initially validated by multi-contrast, high-resolution MRI, and it shows that combination of echogenicity and strain values might be feasible to evaluate the plaque vulnerability.