Noninvasive Identification of the Unstable Carotid Plaque
Section snippets
INTRODUCTION
Carotid atherosclerotic plaque histology has identified several features associated with atheroembolic neurological events. Plaques with large lipid cores1 located close to the flow lumen,2 fibrous cap disruption,3 surface ulceration4 and intraplaque hemorrhage5 have been classified as type VI (complex) plaques.6 These histological features have been associated with atheroembolic events in patients with carotid stenosis (CS). Some of these features may also predispose the plaque to
Patients
After institutional review board approval, informed consent was obtained from all participants. Twenty healthy subjects underwent US scanning to determine pixel intensity of individual tissues. Forty-two patients with 45 CSs were determined to require CEA based on North American Symptomatic Carotid Endarterectomy Trial (NASCET, ≥50% stenosis, symptomatic)21, 22 or Asymptomatic Carotid Atherosclerosis Study (ACAS, ≥60% stenosis, asymptomatic)23 recommendations. The degree of stenosis was
Patient Population
There were 45 carotid plaques from 42 patients included in the study (34 males and 8 females). The mean age was 68 years (range 51–91). The degree of stenosis (based on preoperative US) ranged 70–99%. Eighteen plaques were obtained from symptomatic patients (stroke n = 6, transient ischemic attack n = 9, and amaurosis fugax n = 3), and 27 were from asymptomatic patients. The mean interval between symptoms and CEA in symptomatic patients was 12 weeks. The control group comprised 10 male and 10
DISCUSSION
Randomized controlled trials demonstrating the efficacy of CEA at preventing stroke have utilized the degree of internal carotid artery stenosis as the only criterion for selecting patients at high risk for stroke.21, 22, 23 However, these trials also noted that the majority of patients with high-grade stenoses remained stroke-free even when receiving medical therapy alone.24 It has therefore been proposed that factors in addition to the degree of stenosis may be responsible for determining
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Cited by (63)
The Unstable Carotid Plaque
2022, Anesthesiology ClinicsCitation Excerpt :A cutoff point of 8 mm2 has been suggested to have a good diagnostic value.38 Proximity of the necrotic plaque core to the lumen is associated with symptomatic presentation.39,40 Higher carotid intima-medial thickness is also associated with higher stroke risk.41
Presence of Calcium-Like Tissue Composition in Carotid Plaque is Indicative of Significant Coronary Artery Disease in High-Risk Patients
2019, Journal of the American Society of EchocardiographyEmergency Room Use of “Fast-Track” Ultrasound in Acute Stroke: An Observational Study
2019, Ultrasound in Medicine and BiologyDevelopment of a Carotid Vulnerable Plaque Phantom Model Evaluated by Pixel Distribution Analysis
2018, Ultrasound in Medicine and BiologyAsymptomatic carotid stenosis is associated with cognitive impairment
2017, Journal of Vascular SurgeryCitation Excerpt :The transducer was placed directly over the carotid artery segment containing the plaque to obtain a longitudinal image; it was then swept from the base of the neck to the angle of the mandible to identify and record the cross-sectional image where the tightest stenosis was visualized. The images were digitally recorded and analyzed offline with a computer-assisted image analysis program by independent observers blinded to clinical findings, using previously described approaches.24-26 The longitudinal sectional image that showed the largest amount of plaque was selected for each patient for analysis.
Imaging of high-risk carotid plaques: ultrasound
2017, Seminars in Vascular Surgery