Vulnerable carotid plaque imaging and histopathology without a dedicated MRI receiver coil

Abstract

Stroke is associated with vulnerable carotid artery plaques showing specific histopathologic features, namely a lipid-rich necrotic core, intraplaque hemorrhage, ulceration, and thin fibrous cap. While ultrasound and computed tomography (CT) can identify carotid plaques and determine the extent of stenosis, magnetic resonance imaging (MRI) provides further information regarding plaque composition and morphology. In this feasibility study, three patients with symptomatic, moderately stenosed plaques were imaged with CT angiography (CTA) and MRI (3T and 1.5T) without a dedicated receiver coil. The patients subsequently underwent carotid endarterectomy with en-bloc excision of the plaque. The CT and MR images were analyzed independently by three neuroradiologists to identify vulnerable plaque features. The images were correlated with the histopathology to confirm the findings. All three patients had one or more vulnerable plaque features on histopathology. MRI allowed for better characterization of these features when compared to CTA. The pre- and post-contrast T1-weighted (T1W) images were most helpful for identifying the lipid-rich necrotic core and thin fibrous cap, while the time of flight-magnetic resonance angiography (TOF-MRA) and contrast-enhanced (CE)-MRA were excellent for detecting plaque hemorrhage and ulceration, respectively. The 3T images showed superior spatial and contrast resolution compared to the 1.5T images for all sequences. By providing direct correlation between imaging and histopathology, this study demonstrates that 3T MRI without a dedicated surface coil is an excellent tool for assessing plaque vulnerability. In smaller hospitals or those with limited resources, it is reasonable to consider conventional MRI for patient risk stratification. Further studies are needed to determine how MRI and plaque vulnerability can be incorporated into routine clinical practice.

Inflammation and Endothelial Function Relevant Genetic Polymorphisms and Carotid Plaque in Chinese Population

“…Third, carotid plaque and plaque vulnerability were evaluated by ultrasound. Although ultrasound can identify carotid plaques and determine the extent of stenosis, high-resolution magnetic resonance imaging (HR-MRI) may provide more information regarding plaque composition and morphology 38 ) . Thus, it is necessary to assess carotid plaque using HR-MRI and confirm our current findings in future.…”

Hypothesis of “stroke-stop” formula: a tool for risk index determination in development of acute cerebrovascular disease in asymptomatic individuals with carotid stenosis

“…Clearly, additional markers are required to characterize more precisely the patients who would benefit the most from a surgery. Results of ACSRS study shows that specific baseline clinical characteristics and ultrasonic plaque features after image normalization can independently predict future ipsilateral cerebrovascular events [33][34][35].…”

“Stroke-Stop” Formula: A Tool for Risk Index Determination in Development of Acute Cerebrovascular Disease in Patients with Asymptomatic Internal Carotid Artery Stenosis

“…To provide more objective description, there were developed more detailed classi cations; however, an interobserver agreement was weak and there was observed a low correlation with the histopathological ndings [24,25].…”