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Objectives: In recent years, the use of computer-based techniques has been advocated to improve intima-media thickness (IMT) quantification and its reproducibility. The purpose of this study was to test the diagnostic performance of a new IMT automated algorithm, CARES 3.0, which is a patented class of IMT measurement systems called AtheroEdge (AtheroPoint, LLC, Roseville, CA)., Methods: From 2 different institutions, we analyzed the carotid arteries of 250 patients. The automated CARES 3.0 algorithm was tested versus 2 other automated algorithms, 1 semiautomated algorithm, and a reader reference to assess the IMT measurements. Bland-Altman analysis, regression analysis, and the Student t test were performed., Results: CARES 3.0 showed an IMT measurement bias ± SD of -0.022 ± 0.288 mm compared with the expert reader. The average IMT by CARES 3.0 was 0.852 ± 0.248 mm, and that of the reader was 0.872 ± 0.325 mm. In the Bland-Altman plots, the CARES 3.0 IMT measurements showed accurate values, with about 80% of the images having an IMT measurement bias ranging between -50% and +50%. These values were better than those of the previous CARES releases and the semiautomated algorithm. Regression analysis showed that, among all techniques, the best t value was between CARES 3.0 and the reader., Conclusions: We have developed an improved fully automated technique for carotid IMT measurement on longitudinal ultrasound images. This new version, called CARES 3.0, consists of a new heuristic for lumen-intima and media-adventitia detection, which showed high accuracy and reproducibility for IMT measurement.

In 30% of stroke victims, the cause of stroke has been found to be the stenosis caused by plaques in the carotid artery. Early detection of plaque and subsequent classification of the same into symptomatic and asymptomatic can help the clinicians to choose only those patients who are at a higher risk of stroke for risky surgeries and stenosis treatments. Therefore, in this work, we have proposed a non-invasive computer-aided diagnostic technique to classify the detected plaque into the two classes. Computed tomography (CT) images of the carotid artery images were used to extract Local Binary Pattern (LBP) features and wavelet energy features. Significant features were then used to train and test several supervised learning algorithm based classifiers. The Support Vector Machine (SVM) classifier with various kernel configurations was evaluated using LBP and wavelet features. The SVM classifier presented the highest accuracy of 88%, sensitivity of 90.2%, and specificity of 86.5% for radial basis function (RBF) kernel function. The CT images of the carotid artery provide unique 3D images of the artery and plaque that could be used for calculating percentage of stenosis. Our proposed technique enables automatic classification of plaque into asymptomatic and symptomatic with high accuracy, and hence, it can be used for deciding the course of treatment. We have also proposed a single-valued integrated index (Atheromatic Index) using the significant features which can provide a more objective and faster prediction of the class.

Purpose: The purpose of this paper was to compare manual and automated analysis for the quantification of carotid wall obtained with sonography by using the computed tomography as validation technique., Material and Methods: 21 consecutive patients underwent MDCTA and ultrasound analysis of carotid arteries (mean age 68 years; age range 59-81 years). The intima-media-thickness (IMT) of the 42 carotids was measured with novel and dedicated automated software analysis (called AtheroEdge™, Biomedical Technologies, Denver, CO, USA) and by four observers that manually calculated the IMT. The carotid artery wall thickness (CAWT) was also quantified in the CT datasets. Bland-Altman statistics was employed to measure the agreement between methods. A Student's t-test was used to test the differences between the IMT values of AtheroEdge™. The study obtained the IRB approval., Results: The correlation between automated AtheroEdge™ measurements and those of the human experts were equal to 95.5%, 73.5%, 88.9%, and 81.7%. The IMT coefficient of variation of the human experts was equal to 11.9%. By using a Student's t-test, the differences between the IMT values of AtheroEdge™ and those of the human experts were not found statistically significant (p value=0.02). On comparing AtheroEdge™ (using Ultrasound) with CAWT (using CT), the results suggested a very good concordance of 84.96%., Conclusions: Data of this preliminary study indicate that automated software AtheroEdge™ can analyze with precision the IMT of carotid arteries and that the concordance with CT is optimal., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

In the study of carotid arteries, modern techniques of imaging allow to analyze various alterations beyond simple luminal narrowing, including the morphology of atherosclerotic plaques, the arterial wall and the surrounding structures. By using CTA and MRI it is possible to obtain three-dimensional rendering of anatomic structures with excellent detail for treatment planning. This paper will detail the role of various imaging methods for the assessment of carotid artery pathology with emphasis on the detection, analysis and characterization of carotid atherosclerosis., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Background and Purpose: LA is a condition caused by chronic cerebral ischemia and it represents an independent risk for stroke. The purpose of this work was to determine whether CAWT studied by using MDCTA is correlated with LA and its severity., Materials and Methods: Ninety-eight patients ≥60 years of age were retrospectively studied by using multidetector row CT. Supra-aortic vessel analysis and brain CT were performed in the same procedure. In each patient, CAWT was measured with an internal digital caliper, and the presence and severity of LA were assessed. Correlation coefficients by using Spearman statistics and ROC curves were calculated. A P value < .05 was considered statistically significant., Results: Measurements of the distal common CAWT ranged from 0.5 to 1.53 mm. A correlation between LA and increased CAWT was observed (Pearson correlation, 0.33; P < .001). On the basis of a threshold of 0.9 mm, an important statistical association between increased CAWT and LA (P < .0001) was found. With the same threshold, ROC curve analysis indicated a sensitivity of 55% and a specificity of 75% for LA., Conclusions: The results of this study show a statistically significant correlation between increased CAWT and LA (and its severity).

Aim: To evaluate whether the presence of kinking and coiling of the carotid arteries is associated with symptoms and an increased degree of carotid artery stenosis., Materials and Methods: One hundred and fifty-three consecutive patients examined using multidetector-row computed tomography angiography (MDCTA) were studied retrospectively. The arterial phase was obtained by injecting 4-6ml/s of contrast material. A total of 306 carotid arteries were assessed for the presence of tortuosity. The degree of carotid artery stenosis was measured according to North American Symptomatic Carotid Endarterectomy Trial (NASCET) criteria. Logistic regression analysis was performed to determine whether an independent association existed between the presence of vessel tortuosity, symptoms, and the degree of carotid artery stenosis., Results: Kinking was detected on 37 occasions (12.1%) and coiling on 20 occasions (6.5%). Using Yates's corrected chi-square test, an association between kinking and symptoms (p=0.002) was observed, but not between coiling and symptoms (p=0.31). Logistic regression confirmed that the strongest association was present between stenosis degree and symptoms (p=0.001), but kinking (p=0.009) and age (p=0.001) were also significantly associated with symptoms. A Mann-Whitney test did not demonstrate correlation between coiling (p=0.16) or kinking (p=0.22) and increased degree of carotid artery stenosis., Conclusion: The results suggest that kinking may be associated with symptoms, whereas coiling does not appear to be associated with symptoms. The degree of carotid artery stenosis severity is not related to the presence of vessel tortuosity.

Introduction: Prospective studies have shown that an increased thickness of the carotid wall is a significant predictor of coronary and cerebrovascular complications. Our purpose was to assess the agreement between multi-detector row computed tomography (CT) angiography (MDCTA) and colour Doppler ultrasound (CD-US) in measuring carotid artery wall thickness (CAWT) and the intima-media thickness (IMT)., Methods: Altogether, 97 subjects (age range 64-84 years) were prospectively analysed using a four-detector row CT and a sonographic scanner. In total, 46 subjects had shown cerebral ischaemic symptoms. CAWT and IMT were measured in each patient using MDCTA and CD-US (by applying a digital calliper), respectively. Continuous data were described as the mean value +/- standard deviation and were compared using the Mann-Whitney U test. A p value <0.05 was considered significant. Bland-Altman statistics was employed to measure the agreement between MDCTA and CD-US., Results: CAWT ranged from 0.5 to 1.53 mm, with a mean value of 0.9072 mm. IMT ranged from 0.46 to 1.5 mm, with a mean value of 0.8839 mm. By analysing the Bland-Altman plot, we observed an excellent agreement between CD-US and MDCTA with a bias between methods of 0.023 +/- 0.0424 mm. A limit of agreement from -0.06 to 0.106 was recorded. Correlation coefficient r was 0.9855 (95% confidence interval 0.9808-0.989). Mann-Whitney U test indicated a p value of 0.377., Conclusions: Obtained results indicated a significant agreement between MDCTA and CD-US in the measurement of CAWT and IMT.

Aim: To evaluate the association between types of carotid plaque, the presence of prior ischaemic events detectable with CT, and patient's symptoms., Materials and Methods: Between January 2004 and May 2006, 112 patients were evaluated using multidetector row computed tomography angiography (MDCTA) of the carotid arteries and computed tomography (CT) of the brain. Carotid arteries were categorized by evaluating the degree of stenosis according to North American Symptomatic Carotid Endarterectomy Trial (NASCET) criteria, the type of plaque, and the presence of plaque ulceration. The brain was assessed via CT for the presence, type, and position of lesions. Chi-square tests, Student's t test, and simple logistic regression analysis were performed and the Cohen kappa test was applied for interobserver variability measurement., Results: The Chi-square test indicated a statistically significant association between the presence of fatty plaques (p=0.005) and CT-detectable lesions in the brain (p=0.004). Moreover, the number of patients with CT-detectable brain lesions was greater in patients with >70% stenosis than in those with <70% stenosis (p=0.007). Logistic regression confirmed the association between fatty plaque and symptoms (p=0.001), between >70% stenosis and symptoms (p=0.041), and an inverse association between calcified plaque and symptoms (p=0.009)., Conclusion: MDCTA allows adequate evaluation of the type of plaque. The results of the present study indicate that there is an association between cerebral lesions, symptoms, and fatty plaque in the carotid artery. The degree of stenosis also correlated with cerebral lesions and symptoms. According to the obtained data, the type of carotid plaque should be included among primary parameters in the classification of patients' risk class.

Purpose: Carotid artery plaque with a disrupted fibrous cap is characterized by a higher tendency to rupture, resulting in a higher rate of transitory ischemic attack and stroke. The purpose of our study was to evaluate whether there is a statistically significant correlation between the presence of fissured fibrous cap (FFC) (assessed by using multi-detector-row CT angiography (MDCTA)) and ipsilateral symptomaticity., Material and Methods: 147 patients (105 males, 42 females; mean age 63 years, range 37-84) with a stenosis of at least 50% or a plaque alteration at sonography were retrospectively studied, yielding a total of 294 carotid arteries, by using a multi-detector-row CT (MDCT) scanner. A search for detection of FFC and a correlation with previously registered data about patients' symptomaticity by using statistical assessment were performed. Each examination was assessed independently by two readers and interobserver agreement was calculated., Results: Among the 147 patients included in the study group, 15 were excluded because of inadequate quality images. In the 132 remaining patients, for a total of 264 carotids assessed, 30 FFCs were detected by using MDCTA and overall there were 36 symptomatic patients (12 ipsilateral symptomatic patients with FFC). A statistical correlation between the presence of FFC and symptomaticity (p = 0.0032) was found. The kappa value between readers was 0.781., Conclusions: MDCT may depict FFC and the results of our study suggest that FFC may be used as an indicator for prediction of potential cerebrovascular pathology. The interobserver agreement obtained was good., (Copyright 2009 S. Karger AG, Basel.)

The purpose of this study was to determine if carotid artery wall thickness (CAWT) studied by using multi-detector-row CT angiography (MDCTA) can be considered an effective parameter predictive of increased risk of stroke. A total of 217 patients were retrospectively studied by using MDCTA. In all patients CAWT was measured with an internal digital caliper. Continuous data were described as the mean value +/- standard deviation (SD), and they were compared with Student's t-test. Scatter plots to determine interobserver agreement were performed, and correlation coefficient was calculated with Pearson statistics. A P value <0.05 was considered to mean statistical significance. Measurements of the distal common CAWT ranged from 0.5 to 1.6 mm. In the patient group without stroke, average CAWT was 0.82 mm (0.22 SD), whereas in patient group with stroke it was 1.096 mm (0.21 SD). CAWT in patients without stroke showed statistical difference (P < 0.0001) when compared to patients with stroke. By using a threshold of 1 mm, an important statistical association between thick CAWT and stroke was found (P < 0.0001). In fact, patients with > or = 1 mm CAWT had stroke with an odds ratio of 8.16 when compared with patients with <1 mm CAWT. Resulting data suggested that an increased CAWT is an indicator for risk of stroke. This parameter should be considered in addition to other well-known risk factors such as diabetes, hypertension, smoking, and dyslipidemia.

Background and Purpose: Carotid plaque ulceration is an important risk factor for stroke, and its diagnosis may be very important to plan a correct therapeutic approach. We hypothesized that axial scans and various reconstruction methods could have different specificity and sensitivity in the study of plaque ulceration. The object of this study was to evaluate their role and diagnostic efficacy in patients with carotid plaque complicated by ulceration through the comparison with surgical results., Materials and Methods: From January 2004 to November 2005, 109 patients who underwent a carotid endarterectomy were analyzed using CT angiography for a total of 218 carotid arteries. We assessed every carotid for the presence of ulcerations. For each patient axial image, maximum intensity projection (MIP), multiplanar reconstruction (MPR), shaded surface display (SSD), and volume rendering (VR) reconstructions were obtained., Results: Multidetector row CT angiography (MDCT) found 32 ulcerations; surgical confirmation underlined an overall 93.9% sensitivity (95% confidence interval [CI] 0.858-1.021), and a 98.7% specificity (95% CI, 0.961-1.012). Axial scans and volume rendering images demonstrated the highest sensitivity (90.9% and 87.9%, respectively); SSD, on the contrary, showed the lowest sensitivity: 39.4% (95% CI sensitivity, 0.227-0.561)., Conclusion: Axial scans plus VR reconstruction techniques offer superior depiction of carotid plaque ulceration compared with MIP, MPR, and SSD.