scholarly journals Molecular Imaging of Carotid Plaque Vulnerability

2014 ◽  
Vol 39 (1) ◽  
pp. 5-12 ◽  
Author(s):  
Angelika Alonso ◽  
Dimitrios Artemis ◽  
Michael G. Hennerici
Keyword(s):  
Molecular Imaging ◽  
Carotid Endarterectomy ◽  
Contrast Enhancement ◽  
Phase Contrast ◽  
Late Phase ◽  
High Grade ◽  
Contrast Enhanced Ultrasound ◽  
Plaque Vulnerability ◽  
Carotid Plaques ◽  
Contrast Enhanced

Background: Carotid endarterectomy (CEA) has been shown to be beneficial in patients with high-grade symptomatic carotid artery stenosis. Patients with high-grade asymptomatic stenosis may only exceptionally benefit from CEA during periods of increased plaque vulnerability. Imaging modalities to characterize unstable, vulnerable plaques are strongly needed for better risk stratification in these patients. Summary: Contrast-enhanced ultrasound (CEUS) is a novel and noninvasive technique capable to identify several surrogate markers of vulnerable carotid plaques. The use of specific ultrasound microbubbles allows a reliable detection of microulcerations due to an optimized visualization of the plaque-lumen border. As microbubbles are strictly intravascular tracers, the detection of individual microbubbles within the plaque corresponds to intraplaque neovessels. The accuracy of CEUS in the visualization of newly formed microvessels has been confirmed in histological studies on carotid endarterectomy specimens. Together with the formation of adventitial vasa vasorum, intraplaque neovascularization is a strong predictor for symptomatic disease. The phenomenon of late phase contrast enhancement is based on the adherence of microbubble-containing monocytes on inflamed endothelium. Recent studies suggest that late phase contrast enhancement may reflect endothelial inflammation or activation within carotid plaques. The development of conjugated microbubbles that bind to specific ligands such as thrombotic material or neovessels has led to the term ‘molecular imaging'. CEUS with microbubbles targeted to P-selectin and VCAM-1, key molecules in leukocyte trafficking, was used to detect an inflammatory plaque phenotype, whereas microbubbles coupled to the VEGF-receptor may allow for a detection of neovascularization. Even though imaging with targeted microbubbles is yet in an experimental stage, this technique can visualize active plaque reorganization with increased vulnerability leading to generation of arterio-arterial embolism. Key Messages: The use of contrast-enhanced ultrasound can be recommended to assess atherosclerotic carotid lesions at risk for rupture. Prospective clinical studies are needed to validate the use of CEUS in patients with high risks of recurrent large artery strokes. In particular, this applies to the detection of intraplaque neovascularization, a well-established marker in preclinical and observational studies, while the clinical significance of late phase contrast enhancement still needs to be determined.

Tips and Tricks in Contrast-Enhanced Ultrasound (CEUS) for the Characterization and Detection of Liver Malignancies

2019 ◽  
Vol 40 (04) ◽  
pp. 404-424 ◽  
Author(s):  
Barbara Schellhaas ◽  
Deike Strobel
Keyword(s):  
Liver Cirrhosis ◽  
Contrast Enhancement ◽  
Late Phase ◽  
Therapeutic Monitoring ◽  
Arterial Phase ◽  
Focal Liver Lesions ◽  
Liver Lesions ◽  
Contrast Enhanced Ultrasound ◽  
Liver Malignancies ◽  
Contrast Enhanced

AbstractContrast-enhanced ultrasound (CEUS) has a high diagnostic accuracy in the assessment of focal liver lesions. Clinical context (presence of liver cirrhosis, history of other malignancy versus incidental finding) is crucial for the correct interpretation of CEUS findings. CEUS has to be preceded by structured anamnesis and clinical examination as well as accurate B-mode sonography. Metastases are the most common malignant liver lesions in a non-cirrhotic liver. According to their contrast enhancement in the arterial phase, metastases are categorized as hyper- and hypo-vascular metastases. A common feature of all metastatic lesions is washout of the contrast agent in the portal venous or late phase. In the context of liver cirrhosis, > 95 % of focal liver lesions are hepatocellular carcinomas (HCCs). HCCs typically show arterial phase hyperenhancement, followed by mild and gradual contrast washout occurring very late in the late phase. For intrahepatic cholangiocellular carcinoma (ICC), the pattern of contrast enhancement in the arterial phase can vary. However, all ICCs typically show early and pronounced washout. Other liver malignancies like lymphoma, angiosarcoma, epithelioid hemangioendothelioma and others are very rare. Except for the contrast washout seen in all liver malignancies, they do not display pathognomonic enhancement patterns upon CEUS. Thus, biopsy is indispensable for definite diagnosis of the tumor entity. Furthermore, CEUS is used for the detection of metastases and therapeutic monitoring after local ablative procedures. The examination procedure differs slightly depending on the specific indication (characterization, detection).

scholarly journals Late-Phase Contrast-Enhanced Ultrasound Reflects Biological Features of Instability in Human Carotid Atherosclerosis

Stroke ◽  
2011 ◽  
Vol 42 (12) ◽  
pp. 3634-3636 ◽  
Author(s):  
Joseph Shalhoub ◽  
Claudia Monaco ◽  
David R.J. Owen ◽  
Thomas Gauthier ◽  
Ankur Thapar ◽  
...  
Keyword(s):  
Phase Contrast ◽  
Carotid Atherosclerosis ◽  
Late Phase ◽  
Contrast Enhanced Ultrasound ◽  
Biological Features ◽  
Contrast Enhanced ◽  
Human Carotid

Positive correlation between neovascularization degree of carotid atherosclerosis determined by contrast-enhanced ultrasound and level of serum C-reactive protein

VASA ◽  
2015 ◽  
Vol 44 (3) ◽  
pp. 0187-0194 ◽  
Author(s):  
Xiaoni Chang ◽  
Jun Feng ◽  
Litao Ruan ◽  
Jing Shang ◽  
Yanqiu Yang ◽  
...  
Keyword(s):  
Contrast Enhancement ◽  
Rank Correlation ◽  
Artery Stenosis ◽  
Contrast Enhanced Ultrasound ◽  
C Reactive Protein ◽  
Protein Levels ◽  
Reactive Protein ◽  
Contrast Enhanced ◽  
Grade 3 ◽  
Axis View

Background: Neovascularization is one of the most important risk factors for unstable plaque. This study was designed to correlate plaque thickness, artery stenosis and levels of serum C-reactive protein with the degree of intraplaque enhancement determined by contrast-enhanced ultrasound. Patients and methods: Contrast-enhanced ultrasound was performed on 72 carotid atherosclerotic plaques in 48 patients. Contrast enhancement within the plaque was categorized as grade 1, 2 or 3. Maximum plaque thickness was measured in short-axis view. Carotid artery stenosis was categorized as mild, moderate or severe. Results: Plaque contrast enhancement was not associated with the degree of artery stenosis or with plaque thickness. Serum C-reactive protein levels were positively correlated with the number of new vessels in the plaque. C-reactive protein levels increased in the three groups(Grade 1: 3.72±1.79mg/L; Grade 2: 7.88±4.24 mg/L; Grade 3: 11.02±3.52 mg/L), with significant differences among them (F=10.14, P<0.01), and significant differences between each two groups (P<0.05). Spearman’s rank correlation analysis showed that serum C-reactive protein levels were positively correlated with the degree of carotid plaque enhancement (Rs =0.69, P<0.01). Conclusions: The combination of C-reactive protein levels and intraplaque neovascularization detected by contrast-enhanced ultrasound may allow more accurate evaluation of plaque stability.

scholarly journals Quantitative Analysis of the Time–Intensity Curve of Contrast-Enhanced Ultrasound of the Liver: Differentiation of Benign and Malignant Liver Lesions

Diagnostics ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1244
Author(s):  
Sonja Schwarz ◽  
Dirk-André Clevert ◽  
Michael Ingrisch ◽  
Thomas Geyer ◽  
Vincent Schwarze ◽  
...  
Keyword(s):  
Logistic Regression ◽  
Diagnostic Accuracy ◽  
Late Phase ◽  
Focal Liver Lesions ◽  
Liver Lesions ◽  
Contrast Enhanced Ultrasound ◽  
Contrast Enhanced ◽  
Malignant Lesions ◽  
Benign Liver ◽  
Benign Liver Lesions

Background: To evaluate the diagnostic accuracy of quantitative perfusion parameters in contrast-enhanced ultrasound to differentiate malignant from benign liver lesions. Methods: In this retrospective study 134 patients with a total of 139 focal liver lesions were included who underwent contrast enhanced ultrasound (CEUS) between 2008 and 2018. All examinations were performed by a single radiologist with more than 15 years of experience using a second-generation blood pool contrast agent. The standard of reference was histopathology (n = 60), MRI or CT (n = 75) or long-term CEUS follow up (n = 4). For post processing regions of interests were drawn both inside of target lesions and the liver background. Time–intensity curves were fitted to the CEUS DICOM dataset and the rise time (RT) of contrast enhancement until peak enhancement, and a late-phase ratio (LPR) of signal intensities within the lesion and the background tissue, were calculated and compared between malignant and benign liver lesion using Student’s t-test. Quantitative parameters were evaluated with respect to their diagnostic accuracy using receiver operator characteristic curves. Both features were then combined in a logistic regression model and the cumulated accuracy was assessed. Results: RT of benign lesions (14.8 ± 13.8 s, p = 0.005), and in a subgroup analysis, particular hemangiomas (23.4 ± 16.2 s, p < 0.001) differed significantly to malignant lesions (9.3 ± 3.8 s). The LPR was significantly different between benign (1.59 ± 1.59, p < 0.001) and malignant lesions (0.38 ± 0.23). Logistic regression analysis with RT and LPR combined showed a high diagnostic accuracy of quantitative CEUS parameters with areas under the curve of 0.923 (benign vs. malignant) and 0.929 (hemangioma vs. malignant. Conclusions: Quantified CEUS parameters are helpful to differentiate malignant from benign liver lesions, in particular in case of atypical hemangiomas.

scholarly journals Diagnostic Value of Contrast-Enhanced Ultrasound Evaluation of Malignant and Benign Solitary Thyroid Nodules

2016 ◽  
Vol 70 (1) ◽  
pp. 1-6 ◽  
Author(s):  
Pēteris Priedītis ◽  
Maija Radziņa ◽  
Ilze Štrumfa ◽  
Zenons Narbuts ◽  
Arturs Ozoliņs ◽  
...  
Keyword(s):  
Contrast Enhancement ◽  
Thyroid Nodules ◽  
Fine Needle Biopsy ◽  
Diagnostic Value ◽  
Contrast Enhanced Ultrasound ◽  
Clinical Value ◽  
Additional Tool ◽  
Ultrasound Evaluation ◽  
Contrast Enhanced ◽  
Benign Nodules

Abstract The aim of the study was to investigate the diagnostic value of contrast-enhanced ultrasound (CEUS) in differentiating benign and malignant thyroid nodules. Thirty-five patients with morphologically proved thyroid nodules (17 malignant; 18 benign), underwent CEUS examination. Five enhancement patterns were evaluated: vascularisation, homogeneity, presence of peripheral rim type enhancement, wash-out rate of the contrast medium, and enhancement using microvascular imaging application. Time-intensity curves (TIC) were analysed in post-processing and defined as three types: slow versus rapid and stable versus rapid biphasic wash-out. Diagnostic value of the listed CEUS parameters was calculated. The results showed medium strength correlation between morphology (benign versus malignant nodule) and type of TIC curve rs = 0.38 (p = 0.021), as well as between mode of contrast enhancement rs = 0.39 (p = 0.022) and wash-out pattern rs =0.39 (p = 0.024). The overall pooled sensitivity of selected diagnostic parameters was 82%, specificity 57%, and accuracy 70%. Malignant nodules were characterised by iso- or hypovascular contrast enhancement and slow wash-out, while benign nodules showed hypervascular enhancement with rapid wash-out TIC curve and rim-like pattern. The CEUS patterns significantly differed between malignant and benign thyroid nodules with high diagnostic accuracy. Thus, CEUS has important clinical value as an additional tool to ultrasound and fine needle biopsy.

scholarly journals Effectiveness of contrast-enhanced ultrasound for detecting the staging and grading of bladder cancer: a systematic review and meta-analysis

2020 ◽  
Author(s):  
Xinyue Ge ◽  
Zhong-Kai Lan ◽  
Jing Chen ◽  
Shang-Yong Zhu
Keyword(s):  
Bladder Cancer ◽  
Diagnostic Accuracy ◽  
Likelihood Ratio ◽  
Positive Likelihood Ratio ◽  
Cochrane Library ◽  
Forest Plot ◽  
Low Grade ◽  
High Grade ◽  
Contrast Enhanced Ultrasound ◽  
Contrast Enhanced

Aim: The study retrospectively analysed the accuracy of preoperative contrast-enhanced ultrasound (CEUS) in differenti-ating stage Ta-T1 or low-grade bladder cancer (BC) from stage T2 or high-grade bladder cancer. Material and methods: We systematically searched the literature indexed in PubMed, Embase, and the Cochrane Library for original diagnostic articles of bladder cancer. The diagnostic accuracy of CEUS was compared with cystoscopy and/or transurethral resection of bladder tumors (TURBT). The bivariate logistic regression model was used for data pooling, couple forest plot, diagnostic odds ratio (DOR) and summary receiver operating characteristic (SROC). Results: Five studies met the selection criteria; the overall number of reported bladder cancers patients were 436. The pooled-sensitivity (P-SEN), pooled-specificity (P-SPE), pooled-positive likelihood ratio (PLR+), pooled-negative likelihood ratio (PLR−), DOR, and area under the SROC curve were 94.0% (95%CI: 85%–98%), 90% (95%CI: 83%–95%), 9.5 (95%CI: 5.1–17.6), 0.06 (95%CI: 0.02–0.17), 147 (95%CI: 35–612) and 97% (95% CI: 95%–98%) respectively. Conclusion: CEUS reaches a high efficiency in discriminating Ta-T1 or low-grade bladder cancer from stage T2 or high-grade bladder cancer. It can be a promising method in patients to distinguish T staging and grading of bladder cancer because of its high sensitivity, specificity and diagnostic accuracy.

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