New quantification methods for carotid intra-plaque neovascularization using contrast-enhanced ultrasound.
PURPOSE To evaluate neovascularization within carotid atherosclerotic plaques with contrast-enhanced sonography. METHODS We used contrast-enhanced sonography to examine 63 patients with carotid atherosclerotic plaques. The features of neovascularization within the plaques were analyzed and correlated with plaque size and echogenicity. RESULTS There were 81 atherosclerotic plaques, 62 of which (43 soft and 19 mixed) enhanced after injection of a contrast agent. The enhancement occurred from the carotid wall to the center of the plaque with a short-line pattern in 36 plaques, whereas 26 plaques enhanced from both the carotid wall and the carotid lumen, with a sparse spot pattern. The arrival time of contrast was shorter (p < 0.001) and time to peak was longer (p < 0.001) in the plaques than in the carotid lumen. Time to peak was shorter, whereas enhanced intensity was greater in soft plaques than in mixed plaques (p < 0.01 and p < 0.05, respectively). Among the 19 unenhanced plaques, 6 were hard, 3 were calcified, 3 were soft, and 7 were mixed. The thickness of the unenhanced plaques was <2.4 mm. CONCLUSION Contrast-enhanced sonography allows the noninvasive, dynamic evaluation of neovascularization within carotid plaques, and the presence of neovascularization may correlate with plaque morphology.