Spotty Carotid Plaques Are Associated with Inflammation and the Occurrence of Cerebrovascular Symptoms (original) (raw)
Related papers
Annals of Vascular Surgery, 2020
Background: The aim of this study is to investigate the correlation of clinical and ultrasound parameters with characters of vulnerable atherosclerotic carotid plaque, as evaluated at preoperative magnetic resonance angiography (MRA), in patients submitted to carotid endarterectomy (CEA), in order to develop a clinical risk score for plaque vulnerability. Methods: Preoperative data of patients submitted to CEA for significant carotid stenosis from January 1, 2012 to December 31, 2016 were retrospectively collected. The available case series was randomly divided into 2 groups, including a training (60%) and a validation series (40%). Data of plaque vulnerability were assessed at preoperative MRA scans. Univariate analysis was used on the training series to correlate the preoperative covariates available to the features of plaque vulnerability. Therefore, a backward selection procedure was performed again on the training series and on the validation series to assess if the same variables were associated to data of plaque vulnerability, in order to obtain a prediction model for the risk of plaque vulnerability. Odds ratios (ORs) with 95% confidence intervals were reported. P values <0.05 were considered statistically significant. Results: The training case series consisted of 352 patients, while the validation case series of 248 patients. After univariate analysis and logistic regression, on the training and the validation series respectively, 6 variables were significantly associated to features of vulnerable plaque at preoperative MRA. These included male sex (OR 2.05), diabetes mellitus (OR 3.06), coronary artery disease (OR 1.95), neutrophil/lymphocyte ratio (OR 17.99), platelet counts (OR 1.03), and gray-scale median value (OR 0.84). A nomogram was then obtained from the final logistic model, in order to predict the probability of the presence of vulnerable carotid plaque, using a weighted points system. This risk score was then applied to the validation series. The validation data were found to have a C-index of 0.934.
Ultrasonographic Characterization of Carotid Plaques
Ultrasound in Medicine & Biology, 1998
The composition of atherosclerotic plaques in the carotid artery is assumed to be related to the development of neurological symptoms. The echo patterns produced by B-mode ultrasound may be of use in the assessment of the plaques' composition. It is suggested that fibrotic and ''stable'' plaques are more echogenic than lipid/hemorrhagic and echolucent or ''unstable'' plaques. B-mode ultrasound procedures were performed 1 day prior to surgery on 46 consecutive endarterectomies. Two observers assessed the plaques according to their echo pattern and echogenicity and sorted them into three categories: 1) predominantly echolucent, 2) heterogeneous, and 3) predominantly echogenic. The intraobserver agreement was moderate (kappa ؍ 0.44) and the interobserver agreement low (kappa ؍ 0.38). Furthermore, subjective categorization of plaque types resulted in type 1 plaques being as fibrotic as type 2 or 3 plaques. We conclude that B-mode ultrasound and subsequent subjective categorization of atherosclerotic plaques cannot adequately determine the volume of fibrosis or lipids within the plaque. © 1998 World Federation for Ultrasound in Medicine & Biology.
Ultrasonographic Risk Score of Carotid Plaques
European Journal of Vascular and Endovascular Surgery, 2002
Objective: to determine the relative significance of ultrasonographic parameters of carotid plaques to develop an Activity Index (AI) which could correlate with clinical findings. Method: two hundred and fifteen plaques in 141 patients underwent ultrasonography and computer-assisted structural analysis. In half the patients (group 1), plaques were classified as either homogeneous and heterogeneous and ultrasonographic appearances related symptomatic (SP) or asymptomatic (AP) station. The probability of SP for each ultrasound parameter was used to define an Activity Index (AI). The AI was then applied the second half of patients (Group 2) to assess the value of AI in determining symptomatic station. Results: the parameters with highest morbility were surface disruption, severe stenosis and low grey scale median and, additionally in heterogenous plaques heterogeneity and the presence of a juxta-luminal echolucent area. The power in group 2 of AI to identify symptomatic plaques was determined. Mean AI was for SP-75 (41±100) and for AP-43 (22±100); 78% of SP have AI 4 60 and 70% of AP have AI 5 50. The cut-off point between the two groups was 52. ROC curve analysis of the AI were obtained to determine its diagnostic accuracy. Conclusion: Activity Index is an objective parameter of plaque echostructure that positively correlates with symptoms. AI may contribute to better selection for treatment of patients with carotid artery disease.
American Journal of Neuroradiology, 2019
BACKGROUND AND PURPOSE: Various ultrasonographic features of carortid plaques have been associated with the occurence of stroke, highlighting the need for multi-parametric assessment of plaque's vulnerability. Our aim was to compare ultrasonographic multiparametric indices using color Doppler imaging and contrast-enhanced sonography between symptomatic and asymptomatic carotid plaques. MATERIALS AND METHODS: This was a cross-sectional observational study recruiting 54 patients (72.2% male; median age, 61 years) undergoing sonography and contrast-enhanced sonography. Patients were included if a moderately or severely stenotic internal carotid artery plaque was detected, with the plaque being considered symptomatic if it was ipsilateral to a stroke occuring within the last 6 months. A vulnerability index, previously described by Kanber et al, combined the degree of stenosis, gray-scale median, and a quantitative measure of surface irregularities (surface irregularity index) derived from color Doppler imaging and contrast-enhanced ultrasonography, resulting in 2 vulnerability indices, depending on the surface irregularity index used. Mann-Whitney U and t tests were used to compare variables between groups, and receiver operating characteristic curves were used to compare diagnostic accuracy. RESULTS: Sixty-two plaques were analyzed (50% symptomatic), with a mean degree of stenosis of 68.9%. Symptomatic plaques had a significantly higher degree of stenosis (mean, 74.7% versus 63.1%; P Ͻ .001), a lower gray-scale median (13 versus 38; P ϭ .001), and a higher Kanber vulnerability index based both on color Doppler imaging (median, 61.4 versus 16.5; P Ͻ .001) and contrast-enhanced ultrasonography (median, 88.6 versus 25.2; P Ͻ .001). The area under the curve for the detection of symptomatic plaques was 0.772 for the degree of stenosis alone, 0.783 for the vulnerability index-color Doppler imaging, and 0.802 for the vulnerability index-contrast-enhanced ultrasonography, though no statistical significance was achieved. CONCLUSIONS: Symptomatic plaques had a higher degree of stenosis, lower gray-scale median values, and higher values of the Kanber vulnerability index using both color Doppler imaging and contrast-enhanced ultrasonography for plaque surface delineation. ABBREVIATIONS: AUC ϭ area under the curve; CEUS ϭ contrast-enhanced ultrasonography; CDI ϭ color Doppler imaging; DOS ϭ degree of stenosis; GSM ϭ gray-scale median; IQR ϭ interquartile range; ROC ϭ receiver operating characteristic; SII ϭ surface irregularity index; US ϭ ultrasonography; VI ϭ vulnerability index C arotid atherosclerosis accounts for approximately 10%-15% of all strokes, with thromboembolism from a moderate or severe stenosis representing the underlying mechanism. The degree of internal carotid artery stenosis has long been used as the primary parameter considered for guiding treatment of patients with carotid disease. Nevertheless, it is now well-established that additional plaque features contribute to the vulnerability of the plaque, a term corresponding to the potential of the plaque for stroke or transient ischemic attack. Such features include the composition and surface morphology of the plaque and can be investigated using any imaging technique, from conventional ultrasonography (US) to noninvasive cross-sectional imaging modalities such as multidetector CT angiography. 1-5 Ultrasonography is valuable for the diagnosis of carotid disease and is the
Prediction of High-Risk Asymptomatic Carotid Plaques Based on Ultrasonic Image Features
IEEE Transactions on Information Technology in Biomedicine, 2012
Carotid plaques have been associated with ipsilateral neurological symptoms. High-resolution ultrasound can provide information not only on the degree of carotid artery stenosis but also on the characteristics of the arterial wall including the size and consistency of atherosclerotic plaques. The aim of this study is to determine whether the addition of ultrasonic plaque texture features to clinical features in patients with asymptomatic internal carotid artery stenosis (ACS) improves the ability to identify plaques that will produce stroke. 1121 patients with ACS have been scanned with ultrasound and followed for a mean of 4 years. It is shown that the combination of texture features based on secondorder statistics spatial gray level dependence matrices (SGLDM) and clinical factors improves stroke prediction (by correctly predicting 89 out of the 108 cases that were symptomatic). Here, the best classification results of 77 ± 1.8% were obtained from the use of the SGLDM texture features with support vector machine classifiers. The combination of morphological features with clinical features gave slightly worse classification results of 76 ± 2.6%. These findings need to be further validated in additional prospective studies. Index Terms-Assessment of stroke risk, plaque imaging, ultrasound image analysis. I. INTRODUCTION A therosclerosis of the internal carotid artery (ICA) is an important risk factor for stroke. Using the North American symptomatic carotid endarterectomy trial method [1] for the determination of stenosis the risk of stroke has been shown to range between 0.1-1.6% per year for asymptomatic individuals with ICA stenosis <75-80%. The risk rises to 2-3%
The objective characterisation of ultrasonic carotid plaque features
European Journal of Vascular and Endovascular Surgery, 1998
Objective: To determine the influence of ultrasonic carotid plaque morphology on the incidence of ipsilateral hemispheric symptoms (IHS). Design: Cross-sectional study. Materials: A consecutive series of 80 patients (96 plaques) with more than 50% ICA stenosis was studied. Methods: B mode ultrasonic images were captured and transferred to a computer on magneto-optic disk and standardised using linear scaling so that adventitia would have a grey scale median (GSM) value of 185-I95 and blood 0-5. The GSM and the percentage of echolucent pixels (PEP) in plaques were determined to measure echodensity. Homogeneity, entropy, and contrast were also determined to measure spatial distribution (heterogeneity) of grey shades in each plaque. Each measurement was correlated to presence or absence of IHS. Results: Twenty-~'ve plaques were associated with IHS and 71 plaques were asymptomatic. In symptomatic plaques the mean of GSM was 23 and the mean of PEP was 70%, compared to 38 and 55% respectively in asymptomatic plaques (p=O.02; Wilcoxon test). Sixty per cent of symptomatic plaques were associated with a homogeneity, entropy, and contrast values of >0.2, <2.95, <150 respectively as compared to 40% in asymptomatic plaques. Multiple regression analysis revealed that the GSM and the PEP were the most signi~cant variables (p =0.001) that are related to presence or absence of IHS. Conclusion: This study indicates that computer aided analysis of ultrasonic B mode features of carotid plaques could identify a potentially high-risk subgroup (patients with IHS). A GSM less than 40 or PEP greater than 50% is a good predictor of IHS related to carotid plaques. The fact that these measurements are operator independent and performed after image standardisation should encourage their use in multicentre clinical trials where different operators and equipment are used.
Cerebrovascular Diseases, 2011
Carotid thickening and plaque detected by B-mode imaging ultrasound are useful to improve the ischemic risk evaluation in asymptomatic subjects over and beyond the traditional cardiovascular risk factors. Some plaque’s echographic parameters help describing the vascular risk. We hypothesized that the stenosis degree, plaque surface irregularity, echolucency and texture, compounded in a Total Plaque Risk Score (TPRS), are predictors of the ischemic events in the San Daniele study, a general population-based study of 1,348 subjects followed for 12 years in average. In the 171 subjects with at least one plaque at baseline, high TPRS was the most powerful independent predictor of cerebrovascular events, which occurred in 115 subjects. Addition of plaque characteristics significantly increased the area under the ROC curve (0.90 vs. 0.88, p = 0.04) versus the Framingham risk score alone. The TPRS is a potential new tool to improve the stroke risk prediction.
European Journal of Vascular and Endovascular Surgery, 2011
Introduction: Indication to carotid revascularisation is commonly determined by percent of stenosis as well as neurological symptoms and clinical conditions. High plaque embolic potential is defined as 'vulnerability'; however, its characterisation is not universally used for carotid revascularisation. We investigated the role of contrast-enhanced ultrasonography (CEUS) to identify carotid vulnerable plaque. Methods: Patients undergoing carotid endarterectomy were preoperatively evaluated by cerebral computed tomography (CT) scan and CEUS. Contrast microbubbles detected within the plaque indicated neovascularisation and were quantified by decibel enhancement (dB-E). Plaques were histologically evaluated for five features: (microvessel density, fibrous cap thickness, extension of calcification, inflammatory infiltrate and lipid core) and blindly scored 1e5 to assess plaque vulnerability. Analysis of variance (ANOVA), Fisher's and Student's t-test were used to correlate patients' characteristics, histological features and dB-E. Results: In 22 patients, dB-E (range 2e7.8, mean 4.85 AE 1.9 SD) was significantly greater in symptomatic (7.40 AE 0.5) vs. asymptomatic (3.5 AE 1.4) patients (p Z 0.002). A higher dB-E was significantly associated with thinner fibrous cap (<200 mm, 5.96 AE 1.5 vs. 3 AE 1, p Z 0.01) and greater inflammatory infiltrate (3.2 AE 0.9 vs. 6.4 AE 1.2, p Z 0.03). Plaques with vulnerability score of 5 had significantly higher dB-E compared with those with vulnerability score of 1 (7.6 AE 0.2 vs. 2.5 AE 0.6, respectively, p Z 0.001). Preoperative ipsilateral embolic lesions at CT were correlated with higher dB-E (5.96 AE 1.5 vs. 3.0 AE 1.0, p Z 0.01). Conclusion: CEUS with dB-E is indicative of the extent of plaque neovascularisation. It can be used therefore as a marker for vulnerable plaque. ª
Journal for Vascular Ultrasound, 2012
Background and Purpose Although ultrasound (US) evaluation of the carotid artery for stenosis is the accepted method for identifying risk factors for cerebrovascular (CV) events, patients with specific plaque morphology may be at increased risk. Plaque characterization via US is a potentially useful adjunct to stenotic grading for identifying vulnerable carotid disease. The aim of this study was to systematically review published clinical trials via the use of US to identify vulnerable plaques among both symptomatic and asymptomatic plaques. Methods We used a systematic search using Medline, Embase, and the Cochrane library databases to find relevant studies published between 2001 and 2011. We reviewed randomized, controlled human clinical trials that validated the applicability, diagnostic accuracy, and diagnostic impact of US carotid plaque characterization. For studies reporting qualitative findings, we abstracted information about the study design and technique and the quality o...
Journal of Vascular Surgery, 2005
To identify features on B-mode ultrasonography (US) prevalent in symptomatic plaques and correlate these findings with histopathologic markers of plaque instability.Carotid endarterectomy (CEA) plaques from symptomatic and asymptomatic patients with critical stenoses (>70%) were qualitatively assessed using preoperative B-mode US for echolucency and calcific acoustic shadowing. US echolucency was quantitated ex vivo using computerized techniques for gray-scale median (GSM) analysis. Histopathologic correlates for US plaque echolucency (percentage of necrotic core area) and acoustic shadowing (percentage of calcification area) were determined.Fifty CEA plaques were collected from 48 patients (46 unilateral and two bilateral); 26 of these plaques were from symptomatic patients. Age, degree of stenosis, and atherosclerotic risk factors were similar for the symptomatic and asymptomatic patients. Using preoperative B-mode US, 58%, 35%, and 7% of symptomatic plaques and 18%, 41%, and 41% of asymptomatic plaques were found to be echolucent, echogenic, and calcific, respectively (P < .05). Using ex-vivo B-mode US and GSM analysis, symptomatic plaques were more echolucent (41 ± 19) than asymptomatic plaques (60 ± 13), P < .03. A strong inverse correlation was found between the percent plaque necrotic area core and GSM (R = −0.9, P < .001). Percentage of calcification area in plaques with acoustic shadowing was 66% and only 27% in those without acoustic shadowing (P < .05).Using B-mode US, symptomatic plaques are more echolucent and less calcified than asymptomatic plaques and are associated with a greater degree of histopathologic plaque necrosis. Such features are indicative of plaque instability and should be considered in the decision-making algorithm when selecting patients with high-grade asymptomatic carotid stenosis for intervention.