Measurement of subclinical atherosclerosis: beyond risk factor assessment

PURPOSE OF REVIEW: Assessment of subclinical atherosclerosis using the current available noninvasive imaging modalities holds promise for individual cardiovascular risk management and monitoring efficacy of therapeutic interventions (i.e. surrogate end-points). The present review addresses benefits and limitations of flow-mediated dilatation, intima-media thickness, electron-beam computed tomography and magnetic resonance coronary angiography. RECENT FINDINGS: Both carotid intima-media thickness and peripheral flow-mediated dilatation correlate inversely with cardiovascular risk factors and coronary artery disease. They have been shown to carry predictive value for future cardiovascular events, but clinical application of both intima-media thickness and flow-mediated dilatation demands further methodological maturation of these techniques. Intima thickening has been successfully targeted in numerous intervention trials, but determination of an explicit threshold value beyond which cardiovascular risk significantly increases will facilitate its utility as a routine clinical tool. Electron-beam computed tomography can accurately detect and quantify coronary artery calcification (an established marker of the total coronary plaque burden). However, lack of evidence of its additional predictive power for future coronary events warrants for further research. Finally, magnetic resonance coronary angiography appears to be a promising technique, integrating both functional and anatomical aspects of coronary artery disease. Properly designed studies are needed to determine its value in clinical practice. SUMMARY: Various noninvasive imaging techniques have recently emerged that may find applications in clinical research. However, before widespread clinical utilization, further technical refinement of all of the cited imaging modalities is mandatory. It will be a challenge over the coming few years to clarify whether improvements in surrogate end-points can directly be translated into improved outcomes.     

超声造影与B型超声对人颈动脉内膜-中层厚度及斑块的诊断价值分析

摘要 目的：探讨超声造影（CEUS）与B型超声在诊断人颈动脉内膜-中层厚度（CIMT）及斑块中的临床应用价值。方法：选取2018年10月至2022年12月内蒙古自治区人民医院健康体检者142例,均行颈动脉B型超声和CEUS成像检查。记录左右侧颈动脉各分段点CIMT近壁和远壁值,然后取平均值。采用半定量的方法进行评分,以确定在B型超声和CEUS成像过程中的CIMT可视化。比较B型超声和CEUS成像技术对斑块检出的差异。根据CIMT平均值进行进一步分组,分析CIMT与亚临床左心功能障碍之间的关系。结果：在B型超声成像上,左右侧颈动脉CIMT远壁的可视化评分均明显高于CIMT近壁,差异有统计学意义（P＜0.05）;在CEUS成像上,左右侧颈动脉CIMT远壁的可视化评分均高于CIMT近壁,差异有统计学意义（P＜0.05）。与B型超声成像模式对比,在CEUS成像模式中左右侧颈动脉CIMT远壁和近壁的可视化评分均得到显著提高,差异有统计学意义（P＜0.05）。142例健康体检者中,B型超声总共检测出271个斑块,CEUS总共检测出293个斑块,斑块检出率组间比较差异有统计学意义（P＜0.05）。随着CIMT平均值的逐渐增大,LVM逐渐减小,LVGLS逐渐增大,差异有统计学意义（P＜0.05）。CIMT平均值的大小与LVEDD、LVESD和LVEF差异无统计学意义（P＞0.05）。结论：CEUS改善了CIMT的可视化,并能更好地检测出颈动脉斑块（主要为低回声斑块）,对预测心血管疾病的发生有一定临床价值。     

Relationship between Framingham risk score and subclinical atherosclerosis in carotid plaques:an in vivo study using multi-contrast MRI

The assessment and management of early-stage atherosclerosis are important for the prevention of cardiovascular disease(CVD).In this study,we used multi-contrast magnetic resonance imaging(MRI) to investigate the carotid plaque feature in asymptomatic,at-risk subjects;we also evaluated the correlation between MRI findings and Framingham risk score(FRS).One hundred sixty-six asymptomatic individuals with risk factors for CVD underwent multi-contrast MRI.After the arterial morphology and plaque components were outlined,the differences in carotid plaque burden among the various risk categories were analyzed.The FRS analysis showed that high-risk individuals had thicker vessel wall and higher plaque lipid content than did low risk participants.A substantial proportion of advanced carotid plaques occurred in low and intermediate-risk groups.Multi-contrast MRI may provide incremental value to the FRS in managing asymptomatic at-risk population.     

Capacities of computed tomographic angiography in the diagnosis and estimation of the site, pattern, and degree of vascular bed lesion in nonspecific aortoarteritis

Nonspecific aortoarteritis (NAA) is a chronic inflammatory disease that affects the aorta and its branches. The clinical manifestations of this disease are of a great variety and depend on the site of a lesion and the stage of the disease. A wide range of highly informative noninvasive imaging techniques, such as duplex scanning (DS), magnetic resonance imaging (MRI), and computed tomography (CT) of the aorta and its branches, are used to make a more accurate diagnosis and to determine the site and extent of a vascular bed lesion. The given clinical example suggests that CT angiography of the aorta and its branches is a high-precision technique in determining the site of vascular bed lesion in patients with NAA and the pattern and extent of arterial involvement and that it may be used for both the diagnosis of the disease at its developmental stages and the monitoring of the vessels during pathogenetic therapy.     

Calcium scoring and contrast-enhanced CT angiography

Computed tomography (CT) technology has emerged as the most promising imaging modality for the noninvasive evaluation of the coronary circulation. Of the CT-based approaches, multidetector-row computed tomography (MDCT) and to a lesser extent electron beam computed tomography offer the potential of providing not only data on the spatial extent and burden of coronary calcium content, but also angiographic data, and plaque composition characteristics with the potential for prediction of susceptibility to future cardiovascular events. A number of studies have now confirmed that CT-based assessment of the presence and amount of coronary artery calcium provides incremental prognostic information over traditional risk factors in patients with coronary artery disease and can be employed to refine risk stratification in both asymptomatic and symptomatic subjects. With the advent of several recent advances in CT imaging, it is now possible to provide high resolution (sub-millimeter, isotropic voxels) images of the coronary arteries obtained rapidly with iodinated contrast injected peripherally. MDCT is currently the preferred modality for noninvasive contrast angiography of the coronary arteries by most groups, with a new generation of 64-slice scanners promising to further improve the results of this technique. MDCT-derived angiographic information in conjunction with coronary calcium scoring and plaque characterization has the potential of replacing invasive angiography, as it potentially could provide better global assessment of risk.     

A historical perspective towards a non-invasive treatment for patients with atherosclerosis

The history of atherosclerosis and cardiovascular disease dates back to ancient times. From the teachings of Galen to the response-to-injury hypothesis of Russel Ross, we have now arrived at the concept of the vulnerable plaque. Next to the development of new treatment options for patients with atherosclerosis, also novel diagnostic imaging techniques have been developed to visualise the arterial wall and to characterise plaque composition. In this article the historical context of atherosclerosis and the attempts towards a noninvasive therapy for patients with atherosclerotic diseases are described. (Neth Heart J 2009;17: 140–5.)     

Intelligence in Childhood and Atherosclerosis of the Carotid and Peripheral Arteries in Later Life: The Lothian Birth Cohort 1936

Objective

There is some evidence that people who score higher on tests of intelligence in childhood have lower carotid intima-media thickness and higher ankle brachial index in middle age. These findings need replicating in other, older populations. We investigated the prospective relationship between intelligence in childhood and atherosclerosis in the carotid and peripheral arteries at age 73 years.

Methods

Participants were 713 members of the Lothian Birth Cohort 1936 whose intelligence was assessed at age 11 years. At age 73 years, carotid intima-media thickness and degree of stenosis were measured using ultrasound imaging; ankle-brachial index was measured using Doppler ultrasound.

Results

There were no significant associations between intelligence at age 11 and measures of atherosclerosis at age 73. In age- and sex-adjusted analyses, for a standard deviation higher score in intelligence, intima-media thickness (x 10) was lower by 0.07 (-0.20, 0.06) mm and ankle brachial index (x 10) was lower by 0.09 (-0.24, 0.07); odds ratios for having carotid stenosis >25% or peripheral arterial disease were 0.98 (0.82, 1.16) and 1.05 (0.81, 1.36) respectively.

Conclusion

In this study of people aged 73 years, higher childhood intelligence was not associated with reduced risk of atherosclerosis in the carotid or peripheral arteries.     

Mechanical stresses in carotid plaques using MRI-based fluid-structure interaction models

Risk assessment in patients with carotid atherosclerosis relies on the degree of luminal stenosis. Incorporating morphological information on plaque composition obtained noninvasively through the use of magnetic resonance imaging (MRI) could include other variables besides the degree of stenosis into carotid plaque risk assessment. Knowledge of the morphologic composition of the plaque allows determination of mechanic stresses exerted on the protective fibrous cap, which may be of importance in the assessment of plaque vulnerability. Based on image processing of transverse MRI scans, longitudinal 2D fluid-structure interaction (FSI) simulations of carotid atherosclerotic plaques were performed facilitating in-vivo estimation of longitudinal internal fibrous cap stresses. The FSI simulation combined finite element analysis (FEA) with computational fluid dynamics (CFD) simulations of blood-flow variables. Preliminary results from two symptomatic patients revealed longitudinal stress levels (max. 254.1 and 143.2 kPa) approaching established criteria for plaque rupture at known predilection sites of plaque rupture. Determination of longitudinal fibrous cap stresses may prove useful in assessing plaque vulnerability and improve risk stratification in patients with carotid atherosclerosis.     

Quantification of atherosclerotic plaque activity and vascular inflammation using [18-F] fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT)

Conventional non-invasive imaging modalities of atherosclerosis such as coronary artery calcium (CAC) and carotid intimal medial thickness (C-IMT) provide information about the burden of disease. However, despite multiple validation studies of CAC, and C-IMT, these modalities do not accurately assess plaque characteristics, and the composition and inflammatory state of the plaque determine its stability and, therefore, the risk of clinical events. [(18)F]-2-fluoro-2-deoxy-D-glucose (FDG) imaging using positron-emission tomography (PET)/computed tomography (CT) has been extensively studied in oncologic metabolism. Studies using animal models and immunohistochemistry in humans show that FDG-PET/CT is exquisitely sensitive for detecting macrophage activity, an important source of cellular inflammation in vessel walls. More recently, we and others have shown that FDG-PET/CT enables highly precise, novel measurements of inflammatory activity of activity of atherosclerotic plaques in large and medium-sized arteries. FDG-PET/CT studies have many advantages over other imaging modalities: 1) high contrast resolution; 2) quantification of plaque volume and metabolic activity allowing for multi-modal atherosclerotic plaque quantification; 3) dynamic, real-time, in vivo imaging; 4) minimal operator dependence. Finally, vascular inflammation detected by FDG-PET/CT has been shown to predict cardiovascular (CV) events independent of traditional risk factors and is also highly associated with overall burden of atherosclerosis. Plaque activity by FDG-PET/CT is modulated by known beneficial CV interventions such as short term (12 week) statin therapy as well as longer term therapeutic lifestyle changes (16 months). The current methodology for quantification of FDG uptake in atherosclerotic plaque involves measurement of the standardized uptake value (SUV) of an artery of interest and of the venous blood pool in order to calculate a target to background ratio (TBR), which is calculated by dividing the arterial SUV by the venous blood pool SUV. This method has shown to represent a stable, reproducible phenotype over time, has a high sensitivity for detection of vascular inflammation, and also has high inter-and intra-reader reliability. Here we present our methodology for patient preparation, image acquisition, and quantification of atherosclerotic plaque activity and vascular inflammation using SUV, TBR, and a global parameter called the metabolic volumetric product (MVP). These approaches may be applied to assess vascular inflammation in various study samples of interest in a consistent fashion as we have shown in several prior publications.     

A Non-invasive Method for Determining Biomechanical Properties of the Internal Carotid Artery

ObjectivesMechanical properties of the carotid artery play an important role in the progression of arterial disease such as atherosclerosis. An early change in the mechanical properties of the arteries can be introduced as a novel risk factor for cardiovascular events. The aim of this study is to estimate, in vivo, the elastic biomechanical properties of the internal carotid wall (ICA), from the noninvasive determination of the local arterial wave speed (c).Material and methodsTo achieve this objective, c was determined from a mathematical and physical model developed in our previous work that uses the measurement of the instantaneous blood velocity at two sites by contrast magnetic resonance (PCMR), the study having been conducted on 20 healthy, young and old subjects. The determination of Young's modulus (E) requiring the measurement of the arterial radius (R) and the wall thickness (h), we first estimated the arterial compliance (C). Then from a segmentation of the PCMR image, we evaluated R and thus the elastance given by the product Eh. Finally, in front of the difficulty of measuring h, E was estimated from a statistical study on h.ResultsOur method is sensitive to a variation of the parietal elasticity as it is the case with the age. A statistical test showed that there is a very significant difference between younger and older subjects in terms of speed wave, elastance, compliance, and Young's modulus (p<0.001). Furthermore, these results, in agreement with the reference values reported in the literature, are very promising for detecting a pathological change in parietal elasticity, as is the case in atherosclerosis.ConclusionThus, the in vivo application of this technique shows its potential for clinical evaluation of arterial stiffness ICA as it is fully quantitative, non-invasive and can be performed in real time.     

Development of contrast agents targeted to macrophage scavenger receptors for MRI of vascular inflammation

Atherosclerosis is a leading cause of death in the U.S. Because there is a potential to prevent coronary and arterial disease through early diagnosis, there is a need for methods to image arteries in the subclinical stage as well as clinical stage using various noninvasive techniques, including magnetic resonance imaging (MRI). We describe a development of a novel MRI contrast agent targeted to plaques that will allow imaging of lesion formation. The contrast agent is directed to macrophages, one of the earliest components of developing plaques. Macrophages are labeled through the macrophage scavenger receptor A, a macrophage specific cell surface protein, using an MRI contrast agent derived from scavenger receptor ligands. We have synthesized and characterized these contrast agents with a range of relaxivities. In vitro studies show that the targeted contrast agent accumulates in macrophages, and solution studies indicate that micromolar concentrations are sufficient to produce contrast in an MR image. Cell toxicity and initial biodistribution studies indicate low toxicity, no detectable retention in normal blood vessels, and rapid clearance from blood. The promising performance of this contrast agent targeted toward vascular inflammation opens doors to tracking of other inflammatory diseases such as tumor immunotherapy and transplant acceptance using MRI.     

Secondary flow in the human common carotid artery imaged by MR angiography.

The blood flow in arteries affects both the biology of the vessels and the development of atherosclerosis. The flow is three-dimensional, unsteady, and difficult to measure or to model computationally. We have used phase-shift-based magnetic resonance angiography to image and measure the flow in the common carotid arteries of a healthy human subject. There was curvature of the vessels and thin-slice dynamic flow imaging showed evidence of the presence of secondary motions. Flexing the cervical spine straightened the vessels and reduced the asymmetry of the flow.     

Diagnosing moyamoya syndrome using ultrasound - a case report

Background

Moyamoya syndrome is a vasculopathy characterised by progressive occlusion of the cerebral arteries resulting in the development of abnormal collateral circulation. To diagnose this syndrome, imaging of the cerebral arteries is required including CT- or MR-angiography and conventional angiography. We present a case of moyamoya disease with typical findings detected in the sonography. The diagnosis was suspected after reviewing the initial ultrasound images of the cerebral arteries with evidence for obliterated intracranial arteries and the detection of an existing collateral circulation network.

Case presentation

A 62 years old male patient presented in the hospital’s emergency department with symptoms indicating a subacute cerebrovascular event. Immediate sonographic studies showed a right-sided pulsatile Doppler-signal in the common and internal carotid arteries, suggestive of distal stenoses. In addition, the transcranial examination indicated obliteration of both middle cerebral arteries. Numerous arterial vessels suggestive of leptomeningeal collateral arteries revealed a strong arterial leptomeningeal flow. At this stage of the diagnostic work-up, the collateral circulation network, characteristic of moyamoya disease, was indicated by sonography. Moyamoya syndrome was verified by conventional angiography. The aetiological work remained empty, so the diagnosis of moyamoya disease was established.

Conclusion

Our case report indicates that sonography can be a useful tool for detecting the vaculopathy in moyamoya syndrome. In case routine procedures, such as the CT- or MR-angiography, with evidence for obliterated intracerebral arteries, ultrasound studies might provide important information regarding an existing collateral network in the scope of a moyamoya syndrome.

     

Surrogate markers for atherosclerotic disease

PURPOSE OF REVIEW: Novel treatment modalities for cardiovascular prevention are emerging rapidly. Since it is virtually impossible to evaluate all these new compounds in long-term trials using clinical end points, there is an urgent need for validated surrogate markers of atherosclerosis to save both time and costs. Over the last decade, the use of imaging markers has been widely introduced into drug-development strategies. Here we will discuss the most commonly used techniques. RECENT FINDINGS: Whereas both testing of endothelial function, assessed as flow-mediated dilation, and assessment of carotid intima-media thickness have been shown to predict future cardiovascular events, predominantly intima-media thickness has been used successfully as a surrogate marker in intervention studies. More recently, standardization of intravascular ultrasound has also enabled reproducible assessment of coronary atheroma volume. Multidetector computed tomography and electron-beam computed tomography have proven useful in providing quantitative information on plaque burden and coronary calcium content, respectively. Although cardiovascular magnetic resonance (CMR) is improving continuously, additional technical improvements will be mandatory before this technique can be implemented in multicenter clinical studies. SUMMARY: The imaging modalities reviewed here all provide specific information on either functionality or morphology of the vasculature. The value of carotid intima-media thickness for cardiovascular risk prediction has been studied most extensively. Whereas assessment of plaque burden using intravascular ultrasound appears to be the most direct way to quantify coronary changes, its predictive value for future cardiovascular events remains to be established. Awaiting further technical improvements, CMR is expected to provide the most valuable information for the evaluation of atherosclerosis in the near future.     

Computer aided diagnosis of Coronary Artery Disease,Myocardial Infarction and carotid atherosclerosis using ultrasound images: A review

The diagnosis of Coronary Artery Disease (CAD), Myocardial Infarction (MI) and carotid atherosclerosis is of paramount importance, as these cardiovascular diseases may cause medical complications and large number of death. Ultrasound (US) is a widely used imaging modality, as it captures moving images and image features correlate well with results obtained from other imaging methods. Furthermore, US does not use ionizing radiation and it is economical when compared to other imaging modalities. However, reading US images takes time and the relationship between image and tissue composition is complex. Therefore, the diagnostic accuracy depends on both time taken to read the images and experience of the screening practitioner. Computer support tools can reduce the inter-operator variability with lower subject specific expertise, when appropriate processing methods are used. In the current review, we analysed automatic detection methods for the diagnosis of CAD, MI and carotid atherosclerosis based on thoracic and Intravascular Ultrasound (IVUS). We found that IVUS is more often used than thoracic US for CAD. But for MI and carotid atherosclerosis IVUS is still in the experimental stage. Furthermore, thoracic US is more often used than IVUS for computer aided diagnosis systems.     

2 型糖尿病下肢血管病变评估方法的研究进展

2型糖尿病的发病率逐年增高,下肢血管病变是其严重并发症之一,其临床特点主要有间歇性跋行、静息痛、缺血性坏疽等,严重者可发生肢端坏疽,一旦出现以上症状,治疗相当困难,甚至导致截肢。因此尽早发现并预防该并发症的发生,对于改善患者预后有着极重要的临床价值[1]。目前临床上对于2型糖尿病下肢血管病变的评估方法众多,包括间歇性跛行、静息痛等临床表现,足部动脉搏动检查,踝-肱血压指数,经皮氧分压检查,彩色多普勒超声检查,CT血管成像,MR血管成像,数字减影血管造影等。在现今超声及影像设备和技术飞速发展的大背景下,本文对以上方法的价值、局限性及其最新研究进展作一综述。     

Technology and research developments in carotid image registration

Brain stroke is the leading cause of death worldwide. Mortality, morbidity and economic effects of stroke are alarming. Carotid atherosclerosis is the most common cause of stroke. Early identification, monitoring and quantification of carotid plaque with the help of imaging modalities can help manage the stroke and evaluate the effectiveness of medical therapy. Carotid image registration has the potential to improve the monitoring, quantification and characterization of the disease. It helps to accurately correlate the findings of various imaging modalities for the diagnostic and therapeutic purposes. This paper aims to present the current state-of-the-art in carotid image registration techniques. For the monomodality registration, ultrasound and magnetic resonance imaging are the primary concerns. Multimodality registration will cover the combination of different modalities. The registration process and validation methods for carotid image registration are also discussed.     

Tissue Doppler imaging of carotid plaque wall motion: a pilot study

Background

Studies suggest the physical and mechanical properties of vessel walls and plaque may be of clinical value in the diagnosis and treatment of cardiovascular atherosclerotic disease. The purpose of this pilot study was to investigate the potential clinical application of ultrasound Tissue Doppler Imaging (TDI) of Arterial Wall Motion (AWM) and to quantify simple wall motion indices in normal and diseased carotid arteries.

Methods

224 normal and diseased carotid arteries (0–100% stenoses) were imaged in 126 patients (age 25–88 years, mean 68 ± 11). Longitudinal sections of the carotid bifurcation were imaged using a Philips HDI5000 scanner and L12-5 probe under optimized TDI settings. Temporal and spatial AWMs were analyzed to evaluate the vessel wall displacements and spatial gradients at peak systole averaged over 5 cardiac cycles.

Results

AWM data were successfully extracted in 91% of cases. Within the carotid bifurcation/plaque region, the maximum wall dilation at peak systole ranged from -100 to 750 microns, mean 335 ± 138 microns. Maximum wall dilation spatial gradients ranged 0–0.49, mean 0.14 ± 0.08. The AWM parameters showed a wide variation and had poor correlation with stenoses severity. Case studies illustrated a variety of pertinent qualitative and quantitative wall motion features related to the biophysics of arterial disease.

Conclusion

Our clinical experience, using a challenging but realistic imaging protocol, suggests the use of simple quantitative AWM measures may have limitations due to high variability. Despite this, pertinent features of AWM in normal and diseased arteries demonstrate the potential clinical benefit of the biomechanical information provided by TDI.     

Non-invasive methods for the determination of body and carcass composition in livestock: dual-energy X-ray absorptiometry,computed tomography,magnetic resonance imaging and ultrasound: invited review

The ability to accurately measure body or carcass composition is important for performance testing, grading and finally selection or payment of meat-producing animals. Advances especially in non-invasive techniques are mainly based on the development of electronic and computer-driven methods in order to provide objective phenotypic data. The preference for a specific technique depends on the target animal species or carcass, combined with technical and practical aspects such as accuracy, reliability, cost, portability, speed, ease of use, safety and for in vivo measurements the need for fixation or sedation. The techniques rely on specific device-driven signals, which interact with tissues in the body or carcass at the atomic or molecular level, resulting in secondary or attenuated signals detected by the instruments and analyzed quantitatively. The electromagnetic signal produced by the instrument may originate from mechanical energy such as sound waves (ultrasound – US), ‘photon’ radiation (X-ray-computed tomography – CT, dual-energy X-ray absorptiometry – DXA) or radio frequency waves (magnetic resonance imaging – MRI). The signals detected by the corresponding instruments are processed to measure, for example, tissue depths, areas, volumes or distributions of fat, muscle (water, protein) and partly bone or bone mineral. Among the above techniques, CT is the most accurate one followed by MRI and DXA, whereas US can be used for all sizes of farm animal species even under field conditions. CT, MRI and US can provide volume data, whereas only DXA delivers immediate whole-body composition results without (2D) image manipulation. A combination of simple US and more expensive CT, MRI or DXA might be applied for farm animal selection programs in a stepwise approach.     

Surface Roughness Detection of Arteries via Texture Analysis of Ultrasound Images for Early Diagnosis of Atherosclerosis

There is a strong research interest in identifying the surface roughness of the carotid arterial inner wall via texture analysis for early diagnosis of atherosclerosis. The purpose of this study is to assess the efficacy of texture analysis methods for identifying arterial roughness in the early stage of atherosclerosis. Ultrasound images of common carotid arteries of 15 normal mice fed a normal diet and 28 apoE^−/− mice fed a high-fat diet were recorded by a high-frequency ultrasound system (Vevo 2100, frequency: 40 MHz). Six different texture feature sets were extracted based on the following methods: first-order statistics, fractal dimension texture analysis, spatial gray level dependence matrix, gray level difference statistics, the neighborhood gray tone difference matrix, and the statistical feature matrix. Statistical analysis indicates that 11 of 19 texture features can be used to distinguish between normal and abnormal groups (p<0.05). When the 11 optimal features were used as inputs to a support vector machine classifier, we achieved over 89% accuracy, 87% sensitivity and 93% specificity. The accuracy, sensitivity and specificity for the k-nearest neighbor classifier were 73%, 75% and 70%, respectively. The results show that it is feasible to identify arterial surface roughness based on texture features extracted from ultrasound images of the carotid arterial wall. This method is shown to be useful for early detection and diagnosis of atherosclerosis.