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Shrestha U, Esparza JP, Satapathy SK, Vanatta JM, Abramson ZR, Tipirneni-Sajja A. Hepatic steatosis modeling and MRI signal simulations for comparison of single- and dual-R2* models and estimation of fat fraction at 1.5T and 3T. Comput Biol Med 2024; 174:108448. [PMID: 38626508 DOI: 10.1016/j.compbiomed.2024.108448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Revised: 03/06/2024] [Accepted: 04/07/2024] [Indexed: 04/18/2024]
Abstract
BACKGROUND AND OBJECTIVE Magnetic resonance imaging (MRI) has emerged as a noninvasive clinical tool for assessment of hepatic steatosis. Multi-spectral fat-water MRI models, incorporating single or dual transverse relaxation decay rate(s) (R2*) have been proposed for accurate fat fraction (FF) estimation. However, it is still unclear whether single- or dual-R2* model accurately mimics in vivo signal decay for precise FF estimation and the impact of signal-to-noise ratio (SNR) on each model performance. Hence, this study aims to construct virtual steatosis models and synthesize MRI signals with different SNRs to systematically evaluate the accuracy of single- and dual-R2* models for FF and R2* estimations at 1.5T and 3.0T. METHODS Realistic hepatic steatosis models encompassing clinical FF range (0-60 %) were created using morphological features of fat droplets (FDs) extracted from human liver biopsy samples. MRI signals were synthesized using Monte Carlo simulations for noise-free (SNRideal) and varying SNR conditions (5-100). Fat-water phantoms were scanned with different SNRs to validate simulation results. Fat water toolbox was used to calculate R2* and FF for both single- and dual-R2* models. The model accuracies in R2* and FF estimates were analyzed using linear regression, bias plot and heatmap analysis. RESULTS The virtual steatosis model closely mimicked in vivo fat morphology and Monte Carlo simulation produced realistic MRI signals. For SNRideal and moderate-high SNRs, water R2* (R2*W) by dual-R2* and common R2* (R2*com) by single-R2* model showed an excellent agreement with slope close to unity (0.95-1.01) and R2 > 0.98 at both 1.5T and 3.0T. In simulations, the R2*com-FF and R2*W-FF relationships exhibited slopes similar to in vivo calibrations, confirming the accuracy of our virtual models. For SNRideal, fat R2* (R2*F) was similar to R2*W and dual-R2* model showed slightly higher accuracy in FF estimation. However, in the presence of noise, dual-R2* produced higher FF bias with decreasing SNR, while leading to only marginal improvement for high SNRs and in regions dominated by fat and water. In contrast, single-R2* model was robust and produced accurate FF estimations in simulations and phantom scans with clinical SNRs. CONCLUSION Our study demonstrates the feasibility of creating virtual steatosis models and generating MRI signals that mimic in vivo morphology and signal behavior. The single-R2* model consistently produced lower FF bias for clinical SNRs across entire FF range compared to dual-R2* model, hence signifying that single-R2* model is optimal for assessing hepatic steatosis.
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Affiliation(s)
- Utsav Shrestha
- Department of Biomedical Engineering, The University of Memphis, Memphis, TN, USA; Department of Diagnostic Imaging, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Juan P Esparza
- Department of Biomedical Engineering, The University of Memphis, Memphis, TN, USA
| | - Sanjaya K Satapathy
- Department of Medicine, Division of Hepatology, Donald and Barbara Zucker School of Medicine at Hofstra, Hempstead, NY, USA; Northwell Health Center for Liver Diseases & Transplantation, North Shore University Hospital, Manhasset, NY, USA
| | - Jason M Vanatta
- Department of Surgery, University of Tennessee Health and Science Center, Memphis, TN, USA
| | - Zachary R Abramson
- Department of Diagnostic Imaging, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Aaryani Tipirneni-Sajja
- Department of Biomedical Engineering, The University of Memphis, Memphis, TN, USA; Department of Diagnostic Imaging, St. Jude Children's Research Hospital, Memphis, TN, USA.
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Gemmete JJ. Vessel Wall Characterization Using Quantitative MR Imaging. Neuroimaging Clin N Am 2024; 34:281-292. [PMID: 38604712 DOI: 10.1016/j.nic.2024.02.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/13/2024]
Abstract
MR imaging's exceptional capabilities in vascular imaging stem from its ability to visualize and quantify vessel wall features, such as plaque burden, composition, and biomechanical properties. The application of advanced MR imaging techniques, including two-dimensional and three-dimensional black-blood MR imaging, T1 and T2 relaxometry, diffusion-weighted imaging, and dynamic contrast-enhanced MR imaging, wall shear stress, and arterial stiffness, empowers clinicians and researchers to explore the intricacies of vascular diseases. This array of techniques provides comprehensive insights into the development and progression of vascular pathologies, facilitating earlier diagnosis, targeted treatment, and improved patient outcomes in the management of vascular health.
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Affiliation(s)
- Joseph J Gemmete
- Department of Radiology, Michigan Medicine, 1500 East Medican Center Drive, UH B1D 328, Ann Arbor, MI 48109.
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3
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Taylor EN, Huang N, Lin S, Mortazavi F, Wedeen VJ, Siamwala JH, Gilbert RJ, Hamilton JA. Lipid and smooth muscle architectural pathology in the rabbit atherosclerotic vessel wall using Q-space cardiovascular magnetic resonance. J Cardiovasc Magn Reson 2022; 24:74. [PMID: 36544161 PMCID: PMC9773609 DOI: 10.1186/s12968-022-00897-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 10/19/2022] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Atherosclerosis is an arterial vessel wall disease characterized by slow, progressive lipid accumulation, smooth muscle disorganization, and inflammatory infiltration. Atherosclerosis often remains subclinical until extensive inflammatory injury promotes vulnerability of the atherosclerotic plaque to rupture with luminal thrombosis, which can cause the acute event of myocardial infarction or stroke. Current bioimaging techniques are unable to capture the pathognomonic distribution of cellular elements of the plaque and thus cannot accurately define its structural disorganization. METHODS We applied cardiovascular magnetic resonance spectroscopy (CMRS) and diffusion weighted CMR (DWI) with generalized Q-space imaging (GQI) analysis to architecturally define features of atheroma and correlated these to the microscopic distribution of vascular smooth muscle cells (SMC), immune cells, extracellular matrix (ECM) fibers, thrombus, and cholesteryl esters (CE). We compared rabbits with normal chow diet and cholesterol-fed rabbits with endothelial balloon injury, which accelerates atherosclerosis and produces advanced rupture-prone plaques, in a well-validated rabbit model of human atherosclerosis. RESULTS Our methods revealed new structural properties of advanced atherosclerosis incorporating SMC and lipid distributions. GQI with tractography portrayed the locations of these components across the atherosclerotic vessel wall and differentiated multi-level organization of normal, pro-inflammatory cellular phenotypes, or thrombus. Moreover, the locations of CE were differentiated from cellular constituents by their higher restrictive diffusion properties, which permitted chemical confirmation of CE by high field voxel-guided CMRS. CONCLUSIONS GQI with tractography is a new method for atherosclerosis imaging that defines a pathological architectural signature for the atheromatous plaque composed of distributed SMC, ECM, inflammatory cells, and thrombus and lipid. This provides a detailed transmural map of normal and inflamed vessel walls in the setting of atherosclerosis that has not been previously achieved using traditional CMR techniques. Although this is an ex-vivo study, detection of micro and mesoscale level vascular destabilization as enabled by GQI with tractography could increase the accuracy of diagnosis and assessment of treatment outcomes in individuals with atherosclerosis.
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Affiliation(s)
- Erik N Taylor
- Department of Physiology & Biophysics, Boston University School of Medicine, Boston, MA, USA
- Department of Radiology, UNM School of Medicine, The University of New Mexico, Albuquerque, NM, USA
| | - Nasi Huang
- Department of Physiology & Biophysics, Boston University School of Medicine, Boston, MA, USA
| | - Sunni Lin
- Department of Biomedical Engineering, Boston University, Boston, MA, USA
| | - Farzad Mortazavi
- Department of Anatomy & Neurobiology, Boston University School of Medicine, Boston, MA, USA
| | - Van J Wedeen
- AA Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Jamila H Siamwala
- Department of Molecular Pharmacology, Physiology, and Biotechnology, Warren Alpert Medical School of Brown University, Providence, RI, USA
| | - Richard J Gilbert
- Research Service, Providence VA Medical Center and Warren Alpert Medical School of Brown University, Providence, RI, USA
| | - James A Hamilton
- Department of Physiology & Biophysics, Boston University School of Medicine, Boston, MA, USA.
- Department of Biomedical Engineering, Boston University, Boston, MA, USA.
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Alex A, Ayyappan A, Valakada J, Narasimhaiah D, Pitchai S, Sylaja PN. Role of diffusion-weighted imaging in carotid plaque vulnerability assessment. THE EGYPTIAN JOURNAL OF RADIOLOGY AND NUCLEAR MEDICINE 2022. [DOI: 10.1186/s43055-022-00776-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Abstract
Background
MR plaque imaging is a valuable tool in characterizing carotid atherosclerotic plaque and identifying high-risk features. There are limited data on the role of the widely available single-shot diffusion-weighted imaging (DWI) in plaque characterization along with histological correlation. This study aimed to correlate the plaque characteristics identified by MR imaging in vivo at the level of maximum stenosis with histological plaque characteristics in the postoperative specimen.
Methods
Patients who underwent carotid endarterectomy in a tertiary care center during one and half years were prospectively recruited for non-contrast MR carotid plaque imaging (including single-shot EPI-DWI sequence) in a 3 Tesla MRI using a dedicated carotid coil. An experienced radiologist correlated DWI sequence findings with histopathology of postsurgical sections to confirm the high-risk features.
Results
Twenty-three patients (mean age 66.1 years ± SD 6.25) were evaluated, of which 65% were males and 96% were symptomatic. Apparent diffusion coefficient (ADC) values in location of plaques could differentiate histopathological unstable from stable plaques (0.83 × 10–3 mm2/s vs 1.7 × 10–3 mm2/s; p 0.001), with a sensitivity and specificity of 75% and 79%, respectively, at an ADC cutoff of 1.24 × 10–3 mm2/s. Plaques with and without lipid-rich necrotic core (0.86 × 10–3 mm2/s vs 1.44 × 10–3 mm2/s; p = 0.042) as well as intraplaque hemorrhage could be differentiated (0.751 × 10–3 mm2/s vs 1.352 × 10–3 mm2/s; p 0.037) using the apparent diffusion coefficients.
Conclusion
The widely available single-shot EPI-DWI in assessing plaque characteristics in carotid stenosis is promising and correlated with histopathological features. Diffusion-weighted imaging will be a helpful adjunct in patients when contrast administration is intolerable.
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Exploring arterial tissue microstructural organization using non-Gaussian diffusion magnetic resonance schemes. Sci Rep 2021; 11:22247. [PMID: 34782651 PMCID: PMC8593063 DOI: 10.1038/s41598-021-01476-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 10/13/2021] [Indexed: 12/02/2022] Open
Abstract
The purpose of this study was to characterize the alterations in microstructural organization of arterial tissue using higher-order diffusion magnetic resonance schemes. Three porcine carotid artery models namely; native, collagenase treated and decellularized, were used to estimate the contribution of collagen and smooth muscle cells (SMC) on diffusion signal attenuation using gaussian and non-gaussian schemes. The samples were imaged in a 7 T preclinical scanner. High spatial and angular resolution diffusion weighted images (DWIs) were acquired using two multi-shell (max b-value = 3000 s/mm2) acquisition protocols. The processed DWIs were fitted using monoexponential, stretched-exponential, kurtosis and bi-exponential schemes. Directionally variant and invariant microstructural parametric maps of the three artery models were obtained from the diffusion schemes. The parametric maps were used to assess the sensitivity of each diffusion scheme to collagen and SMC composition in arterial microstructural environment. The inter-model comparison showed significant differences across the considered models. The bi-exponential scheme based slow diffusion compartment (Ds) was highest in the absence of collagen, compared to native and decellularized microenvironments. In intra-model comparison, kurtosis along the radial direction was the highest. Overall, the results of this study demonstrate the efficacy of higher order dMRI schemes in mapping constituent specific alterations in arterial microstructure.
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Kim SE, Parker DL, Roberts JA, Treiman GS, Alexander M, Baradaran H, de Havenon A, McNally JS. Differentiation of symptomatic and asymptomatic carotid intraplaque hemorrhage using 3D high-resolution diffusion-weighted stack of stars imaging. NMR IN BIOMEDICINE 2021; 34:e4582. [PMID: 34296793 DOI: 10.1002/nbm.4582] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 06/14/2021] [Accepted: 06/15/2021] [Indexed: 06/13/2023]
Abstract
Ischemic events related to carotid disease are far more strongly associated with plaque instability than stenosis. 3D high-resolution diffusion-weighted (DW) imaging can provide quantitative diffusion measurements on carotid atherosclerosis and may improve detection of vulnerable intraplaque hemorrhage (IPH). The 3D DW-stack of stars (SOS) sequence was implemented with 3D SOS acquisition combined with DW preparation. After simulation of signals created from 3D DW-SOS, phantom studies were performed. Three healthy subjects and 20 patients with carotid disease were recruited. Apparent diffusion coefficient (ADC) values were statistically analyzed on three subgroups by using a two-group comparison Wilcoxon-Mann-Whitney U test with p values less than 0.05: symptomatic versus asymptomatic; IPH-positive versus IPH-negative; and IPH-positive symptomatic versus asymptomatic plaques to determine the relationship with plaque vulnerability. ADC values calculated by 3D DW-SOS provided values similar to those calculated from other techniques. Mean ADC of symptomatic plaque was significantly lower than asymptomatic plaque (0.68 ± 0.18 vs. 0.98 ± 0.16 x 10-3 mm2 /s, p < 0.001). ADC was also significantly lower in IPH-positive versus IPH-negative plaque (0.68 ± 0.13 vs. 1.04 ± 0.11 x 10-3 mm2 /s, p < 0.001). Additionally, ADC was significantly lower in symptomatic versus asymptomatic IPH-positive plaque (0.57 ± 0.09 vs. 0.75 ± 0.11 x 10-3 mm2 /s, p < 0.001). Our results provide strong evidence that ADC measurements from 3D DW-SOS correlate with the symptomatic status of extracranial internal carotid artery plaque. Further, ADC improved discrimination of symptomatic plaque in IPH. These data suggest that diffusion characteristics may improve detection of destabilized plaque leading to elevated stroke risk.
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Affiliation(s)
- Seong-Eun Kim
- Utah Center for Advanced Imaging Research, University of Utah, Salt Lake City, Utah, USA
- Department of Radiology and Imaging Sciences, University of Utah, Salt Lake City, Utah, USA
| | - Dennis L Parker
- Utah Center for Advanced Imaging Research, University of Utah, Salt Lake City, Utah, USA
- Department of Radiology and Imaging Sciences, University of Utah, Salt Lake City, Utah, USA
| | - John A Roberts
- Utah Center for Advanced Imaging Research, University of Utah, Salt Lake City, Utah, USA
- Department of Radiology and Imaging Sciences, University of Utah, Salt Lake City, Utah, USA
| | - Gerald S Treiman
- Department of Veterans Affairs, VASLCHCS, Salt Lake City, Utah, USA
| | - Matthew Alexander
- Utah Center for Advanced Imaging Research, University of Utah, Salt Lake City, Utah, USA
- Department of Radiology and Imaging Sciences, University of Utah, Salt Lake City, Utah, USA
| | - Hediyeh Baradaran
- Utah Center for Advanced Imaging Research, University of Utah, Salt Lake City, Utah, USA
- Department of Radiology and Imaging Sciences, University of Utah, Salt Lake City, Utah, USA
| | - Adam de Havenon
- Department of Neurology, University of Utah, Salt Lake City, Utah, USA
| | - J Scott McNally
- Utah Center for Advanced Imaging Research, University of Utah, Salt Lake City, Utah, USA
- Department of Radiology and Imaging Sciences, University of Utah, Salt Lake City, Utah, USA
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Yu YN, Liu MW, Villablanca JP, Li ML, Xu YY, Gao S, Feng F, Liebeskind DS, Scalzo F, Xu WH. Middle Cerebral Artery Plaque Hyperintensity on T2-Weighted Vessel Wall Imaging Is Associated with Ischemic Stroke. AJNR Am J Neuroradiol 2019; 40:1886-1892. [PMID: 31624115 DOI: 10.3174/ajnr.a6260] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2019] [Accepted: 08/27/2019] [Indexed: 01/09/2023]
Abstract
BACKGROUND AND PURPOSE Vessel wall imaging can identify intracranial atherosclerotic plaque and give clues about its components. We aimed to investigate whether the plaque hyperintensity in the middle cerebral artery on T2-weighted vessel wall imaging is associated with ischemic stroke. MATERIALS AND METHODS We retrospectively reviewed our institutional vessel wall MR imaging data base. Patients with an acute ischemic stroke within 7-day onset in the MCA territory were enrolled. Patients with stroke and stenotic MCA plaque (stenosis degree, ≥50%) were included for analysis. Ipsilateral MCA plaque was defined as symptomatic, and contralateral plaque, as asymptomatic. Plaque was manually delineated on T2-weighted vessel wall imaging. The plaque signal was normalized to the ipsilateral muscle signal. The thresholds and volume of normalized plaque signal were investigated using logistic regression and receiver operating characteristic analysis to determine the association between normalized plaque signal and stroke. RESULTS One hundred eight stenotic MCAs were analyzed (from 88 patients, 66 men; mean age, 58 ± 15 years), including 72 symptomatic and 36 asymptomatic MCA plaques. Symptomatic MCA plaque showed larger plaque hyperintensity volume compared with asymptomatic MCA plaque. The logistic regression model incorporating stenosis degree, remodeling ratio, and normalized plaque signal 1.3-1.4 (OR, 6.25; 95% CI, 1.90-20.57) had a higher area under curve in differentiating symptomatic/asymptomatic MCA plaque, compared with a model with only stenosis degree and remodeling ratio (area under curve, 0.884 versus 0.806; P =.008). CONCLUSIONS The MCA plaque hyperintensity on T2-weighted vessel wall imaging is independently associated with ischemic stroke and adds value to symptomatic MCA plaque classification. Measuring the normalized signal intensity may serve as a practical and integrative approach to the analysis of intracranial atherosclerotic plaque.
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Affiliation(s)
- Y-N Yu
- From the Departments of Neurology (Y.-N.Y., Y.-Y.X., S.G., W.-H.X.)
| | - M-W Liu
- Neurovascular Imaging Research Core and UCLA Stroke Center (M.-W.L., D.S.L., F.S.), Los Angeles, California
| | | | - M-L Li
- Radiology (M.-L.L., F.F.), Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Y-Y Xu
- From the Departments of Neurology (Y.-N.Y., Y.-Y.X., S.G., W.-H.X.)
| | - S Gao
- From the Departments of Neurology (Y.-N.Y., Y.-Y.X., S.G., W.-H.X.)
| | - F Feng
- Radiology (M.-L.L., F.F.), Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - D S Liebeskind
- Neurovascular Imaging Research Core and UCLA Stroke Center (M.-W.L., D.S.L., F.S.), Los Angeles, California
| | - F Scalzo
- Neurovascular Imaging Research Core and UCLA Stroke Center (M.-W.L., D.S.L., F.S.), Los Angeles, California
| | - W-H Xu
- From the Departments of Neurology (Y.-N.Y., Y.-Y.X., S.G., W.-H.X.)
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Early Embolization After Carotid Artery Stenting with Mesh-Covered Stent: Role of Diffusion-Weighted Magnetic Resonance Imaging as Pre-procedural Predictor and Discriminant Between Intra- and Post-procedural Events. Cardiovasc Intervent Radiol 2019; 42:812-819. [PMID: 30783778 DOI: 10.1007/s00270-019-02173-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2018] [Accepted: 01/30/2019] [Indexed: 10/27/2022]
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9
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Ota H, Tamura H, Itabashi R, Yazawa Y, Nakamura Y, Hisamatsu K, Takamatsu M, Endo H, Niizuma K, Enomoto Y, Nagasaka T, Kajita K, Watanabe M, Yoshimura S, Yuan C. Quantitative characterization of carotid plaque components using MR apparent diffusion coefficients and longitudinal relaxation rates at 3T: A comparison with histology. J Magn Reson Imaging 2018; 48:1657-1667. [DOI: 10.1002/jmri.26216] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 05/22/2018] [Indexed: 11/11/2022] Open
Affiliation(s)
- Hideki Ota
- Department of Diagnostic Radiology; Tohoku University Hospital; Miyagi Japan
| | - Hajime Tamura
- Division of Medical Physics; Tohoku University Graduate School of Medicine; Miyagi Japan
| | - Ryo Itabashi
- Department of Stroke Neurology; Kohnan Hospital; Miyagi Japan
| | - Yukako Yazawa
- Department of Stroke Neurology; Kohnan Hospital; Miyagi Japan
| | - Yasuhiro Nakamura
- Division of Pathology, Faculty of Medicine; Tohoku Medical and Pharmaceutical University, Miyagi, Japan; Miyagi Japan
| | - Kenji Hisamatsu
- Pathology Division; Gifu University Hospital; Gifu Japan
- Department of Tumor Pathology; Gifu University Graduate School of Medicine; Gifu Japan
| | - Manabu Takamatsu
- Department of Pathology; The Cancer Institute Hospital, Japanese Foundation for Cancer Research; Tokyo Japan
| | - Hidenori Endo
- Department of Neurosurgery; Tohoku University Graduate School of Medicine; Miyagi Japan
| | - Kuniyasu Niizuma
- Department of Neurosurgery; Tohoku University Graduate School of Medicine; Miyagi Japan
| | - Yukiko Enomoto
- Department of Neurosurgery; Gifu University Graduate School of Medicine; Gifu Japan
| | - Tatsuo Nagasaka
- Department of Radiological Technology; Tohoku University Hospital; Miyagi Japan
| | - Kimihiro Kajita
- Department of Radiology service; Gifu University Hospital; Gifu Japan
| | - Mika Watanabe
- Department of Pathology; Tohoku University Hospital; Miyagi Japan
| | | | - Chun Yuan
- Department of Radiology; University of Washington; Seattle Washington USA
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Taylor E, Huang N, Bodde J, Ellison A, Killiany R, Bachschmid MM, Hamilton J. MRI of atherosclerosis and fatty liver disease in cholesterol fed rabbits. J Transl Med 2018; 16:215. [PMID: 30068362 PMCID: PMC6071403 DOI: 10.1186/s12967-018-1587-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Accepted: 07/20/2018] [Indexed: 02/07/2023] Open
Abstract
Background The globally rising obesity epidemic is associated with a broad spectrum of diseases including atherosclerosis and non-alcoholic fatty liver (NAFL) disease. In the past, research focused on the vasculature or liver, but chronic systemic effects and inter-organ communication may promote the development of NAFL. Here, we investigated the impact of confined vascular endothelial injury, which produces highly inflamed aortic plaques that are susceptible to rupture, on the progression of NAFL in cholesterol fed rabbits. Methods Aortic atherosclerotic inflammation (plaque Gd-enhancement), plaque size (vessel wall area), and composition, were measured with in vivo magnetic resonance imaging (MRI) in rabbits fed normal chow or a 1% cholesterol-enriched atherogenic diet. Liver fat was quantified with magnetic resonance spectroscopy (MRS) over 3 months. Blood biomarkers were monitored in the animals, with follow-up by histology. Results Cholesterol-fed rabbits with and without injury developed hypercholesterolemia, NAFL, and atherosclerotic plaques in the aorta. Compared with rabbits fed cholesterol diet alone, rabbits with injury and cholesterol diets exhibited larger, and more highly inflamed plaques by MRI (P < 0.05) and aggravated liver steatosis by MRS (P < 0.05). Moreover, after sacrifice, damaged (ballooning) hepatocytes and extensive liver fibrosis were observed by histology. Elevated plasma gamma-glutamyl transferase (GGT; P = 0.014) and the ratio of liver enzymes aspartate and alanine aminotransferases (AST/ALT; P = 0.033) indicated the progression of steatosis to non-alcoholic steatohepatitis (NASH). Conclusions Localized regions of highly inflamed aortic atherosclerotic plaques in cholesterol-fed rabbits may contribute to progression of fatty liver disease to NASH with fibrosis. Electronic supplementary material The online version of this article (10.1186/s12967-018-1587-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Erik Taylor
- Department of Physiology and Biophysics, Boston University School of Medicine, 700 Albany Street, W302, Boston, MA, 02118-2526, USA
| | - Nasi Huang
- Department of Physiology and Biophysics, Boston University School of Medicine, 700 Albany Street, W302, Boston, MA, 02118-2526, USA
| | - Jacob Bodde
- Department of Physiology and Biophysics, Boston University School of Medicine, 700 Albany Street, W302, Boston, MA, 02118-2526, USA
| | - Andrew Ellison
- Anatomy and Neurobiology, Boston University School of Medicine, Boston, MA, USA
| | - Ronald Killiany
- Anatomy and Neurobiology, Boston University School of Medicine, Boston, MA, USA
| | - Markus Michael Bachschmid
- Vascular Biology Section, Whitaker Cardiovascular Institute, and Cardiovascular Proteomics Center, Boston University School of Medicine, Boston, MA, USA
| | - James Hamilton
- Department of Physiology and Biophysics, Boston University School of Medicine, 700 Albany Street, W302, Boston, MA, 02118-2526, USA.
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Shahid SS, Gaul RT, Kerskens C, Flamini V, Lally C. Quantifying the ultrastructure of carotid arteries using high-resolution micro-diffusion tensor imaging—comparison of intact versus open cut tissue. ACTA ACUST UNITED AC 2017; 62:8850-8868. [DOI: 10.1088/1361-6560/aa9159] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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12
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Coolen BF, Calcagno C, van Ooij P, Fayad ZA, Strijkers GJ, Nederveen AJ. Vessel wall characterization using quantitative MRI: what's in a number? MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2017; 31:201-222. [PMID: 28808823 PMCID: PMC5813061 DOI: 10.1007/s10334-017-0644-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Revised: 07/04/2017] [Accepted: 07/18/2017] [Indexed: 12/15/2022]
Abstract
The past decade has witnessed the rapid development of new MRI technology for vessel wall imaging. Today, with advances in MRI hardware and pulse sequences, quantitative MRI of the vessel wall represents a real alternative to conventional qualitative imaging, which is hindered by significant intra- and inter-observer variability. Quantitative MRI can measure several important morphological and functional characteristics of the vessel wall. This review provides a detailed introduction to novel quantitative MRI methods for measuring vessel wall dimensions, plaque composition and permeability, endothelial shear stress and wall stiffness. Together, these methods show the versatility of non-invasive quantitative MRI for probing vascular disease at several stages. These quantitative MRI biomarkers can play an important role in the context of both treatment response monitoring and risk prediction. Given the rapid developments in scan acceleration techniques and novel image reconstruction, we foresee the possibility of integrating the acquisition of multiple quantitative vessel wall parameters within a single scan session.
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Affiliation(s)
- Bram F Coolen
- Department of Biomedical Engineering and Physics, Academic Medical Center, PO BOX 22660, 1100 DD, Amsterdam, The Netherlands. .,Department of Radiology, Academic Medical Center, Amsterdam, The Netherlands.
| | - Claudia Calcagno
- Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA.,Department of Radiology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Pim van Ooij
- Department of Radiology, Academic Medical Center, Amsterdam, The Netherlands
| | - Zahi A Fayad
- Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA.,Department of Radiology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Gustav J Strijkers
- Department of Biomedical Engineering and Physics, Academic Medical Center, PO BOX 22660, 1100 DD, Amsterdam, The Netherlands
| | - Aart J Nederveen
- Department of Radiology, Academic Medical Center, Amsterdam, The Netherlands
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13
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Xia J, Yin A, Li Z, Liu X, Peng X, Xie N. Quantitative Analysis of Lipid-Rich Necrotic Core in Carotid Atherosclerotic Plaques by In Vivo Magnetic Resonance Imaging and Clinical Outcomes. Med Sci Monit 2017; 23:2745-2750. [PMID: 28584227 PMCID: PMC5470833 DOI: 10.12659/msm.901864] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Background The aim of this study was to explore the accuracy of in vivo magnetic resonance imaging (MRI) in the quantitative evaluation of lipid-rich necrotic core (LRNC) in carotid atherosclerotic plaques compared with histopathology, and to assess the association of LRNC size with cerebral ischemia symptoms. Material/Methods Thirty patients were enrolled and 19 patients (16 men and 3 women) were analyzed. All the patients were submitted to MRI on a Siemens Avanto (1.5-Tesla) device before carotid endarterectomy (CEA). The scanning protocol included three-dimensional time of flight (3D TOF), T1-weighted image (T1WI), T2-weighted image (T2WI), turbo spin-echo T2-weighted (T2-TSE), and contrast-enhanced T1-weighted image. MRI images were reviewed for quantitative measurements of LRNC areas. LRNC specimens were collected for histology. Percentages of LRNC area to total vessel area were assessed to determine the association of MRI with histological findings. Results There were 151 pairs of matched MRI and pathological sections. LRNC area percentages (LRNC area/vessel area) measured by MRI and histology were 20.6±9.0% and 18.7±9.5%, respectively (r=0.69, p<0.001). Twelve out of 19 patients had symptoms (S-group; 3 had recent stroke, 3 had a recent stroke and a history of transient ischemic attack (TIA), and 6 had TIA); the remaining 7 subjects showed no symptoms (NS-group). LRNC area percentages in the S- and NS-groups were 22.2±5.8% and 12.6±10.7%, respectively (p<0.05). Conclusions MRI can quantitatively measure LRNC in carotid atherosclerotic plaques, and may be useful in predicting the rupture risk of plaques. These findings provide a basis for imaging use in individualized treatment plan.
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Affiliation(s)
- Jun Xia
- Department of Radiology, Shenzhen No.2 People's Hospital (the First Affiliated Hospital of Shenzhen University), Shenzhen, Guangdong, China (mainland)
| | - Anyu Yin
- Department of Radiology, Shenzhen No.2 People's Hospital (the First Affiliated Hospital of Shenzhen University), Shenzhen, Guangdong, China (mainland)
| | - Zhenzhou Li
- Department of Ultrasound, Shenzhen No. 2 People's Hospital (the First Affiliated Hospital of Shenzhen University), Shenzhen, Guangdong, China (mainland)
| | - Xin Liu
- Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China (mainland)
| | - Xianghong Peng
- Core Laboratory, Shenzhen No. 2 People's Hospital (the First Affiliated Hospital of Shenzhen University), Shenzhen, Guangdong, China (mainland)
| | - Ni Xie
- Core Laboratory, Shenzhen No. 2 People's Hospital (the First Affiliated Hospital of Shenzhen University), Shenzhen, Guangdong, China (mainland)
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14
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Yao B, Yang L, Wang G, Shi H, Wang S, Li H, Chen W, Chan Q. Diffusion measurement of intraplaque hemorrhage and intramural hematoma using diffusion weighted MRI at 3T in cervical artery. Eur Radiol 2015; 26:3737-43. [PMID: 26670319 DOI: 10.1007/s00330-015-4149-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Revised: 11/26/2015] [Accepted: 11/30/2015] [Indexed: 01/01/2023]
Affiliation(s)
- Bin Yao
- The Second Affiliated Hospital of Nanchang University, Nanchang, 330006, Jiangxi, China
| | - Li Yang
- Department of Radiology, Shanghai Institute of Medical Imaging, Zhongshan Hospital, Fudan University, Shanghai, 200032, People's Republic of China
| | - Guangbin Wang
- Shandong Medical Imaging Research Institute, Shandong University, Jinan, 250021, Shandong, People's Republic of China.
| | - Honglu Shi
- Shandong Medical Imaging Research Institute, Shandong University, Jinan, 250021, Shandong, People's Republic of China
| | - Shanshan Wang
- Shandong Medical Imaging Research Institute, Shandong University, Jinan, 250021, Shandong, People's Republic of China
| | - Huihua Li
- Shandong Medical Imaging Research Institute, Shandong University, Jinan, 250021, Shandong, People's Republic of China
| | - Weibo Chen
- Philips Healthcare, Shanghai, People's Republic of China
| | - Queenie Chan
- Philips Healthcare, Shanghai, People's Republic of China
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15
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Meletta R, Borel N, Stolzmann P, Astolfo A, Klohs J, Stampanoni M, Rudin M, Schibli R, Krämer SD, Müller Herde A. Ex vivo differential phase contrast and magnetic resonance imaging for characterization of human carotid atherosclerotic plaques. Int J Cardiovasc Imaging 2015; 31:1425-34. [DOI: 10.1007/s10554-015-0706-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Accepted: 07/06/2015] [Indexed: 11/25/2022]
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16
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Hashimura N, Mutoh T, Matsuda K, Matsumoto K. Evaluation and management of plaque protrusion or thrombus following carotid artery stenting. Neurol Med Chir (Tokyo) 2015; 55:149-54. [PMID: 25746309 PMCID: PMC4533408 DOI: 10.2176/nmc.oa.2014-0105] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Carotid artery stenting (CAS) has become a common treatment for carotid artery stenosis. However, complications, such as an ischemic event, can occur with CAS during intra- and post-operative periods. Among these ischemic complications, plaque protrusion into the stent and thrombus on the stent have occurred after CAS. We retrospectively evaluated the temporal profile and treatment options for these complications in 32 consecutive cases who underwent CAS at our hospital between April 2009 and December 2011. The cases were evaluated pre-operatively for risk factors, as well as the plaque morphology and characteristics using computed tomographic angiography (CTA), ultrasound (US), and magnetic resonance imaging (MRI). Post-operatively, lesions were examined by CTA and/or US within 1 week of CAS. As a result, among the 32 cases, 8 experienced plaque protrusions or thrombus, which were treated with medication (anti-platelet and/or anti-coagulation reinforcement). In 7 of these 8 cases, the plaque protrusion or thrombus was stabilized with medication alone. However, the remaining case showed growth and migration of the plaque protrusion or thrombus when treated with medication alone, and therefore, required further endovascular treatment. We identified that a history of symptomatic cerebral infarction and plaques with ulceration were risk factors for plaque protrusion or thrombus formation after CAS, and pre dilatation can decrease the risk of these complications. Medication was effective in most cases of plaque protrusion or thrombus; however, further endovascular treatment was required when medication alone was unsuccessful.
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17
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Nogueira L, Brandão S, Nunes RG, Ferreira HA, Loureiro J, Ramos I. Breast DWI at 3 T: influence of the fat-suppression technique on image quality and diagnostic performance. Clin Radiol 2014; 70:286-94. [PMID: 25555315 DOI: 10.1016/j.crad.2014.11.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Revised: 11/12/2014] [Accepted: 11/19/2014] [Indexed: 10/24/2022]
Abstract
AIM To evaluate two fat-suppression techniques: short tau inversion recovery (STIR) and spectral adiabatic inversion recovery (SPAIR) regarding image quality and diagnostic performance in diffusion-weighted imaging (DWI) of breast lesions at 3 T. MATERIALS AND METHODS Ninety-two women (mean age 48 ± 12.1 years; range 21-78 years) underwent breast MRI. Two DWI pulse sequences, with b-values (50 and 1000 s/mm(2)) were performed with STIR and SPAIR. The signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), suppression homogeneity, and apparent diffusion coefficient (ADC) values were quantitatively assessed for each technique. Values were compared between techniques and lesion type. Receiver operating characteristics (ROC) analysis was used to evaluate lesion discrimination. RESULTS One hundred and fourteen lesions were analysed (40 benign and 74 malignant). SNR and CNR were significantly higher for DWI-SPAIR; fat-suppression uniformity was better for DWI-STIR (p < 1 × 10(-4)). ADC values for benign and malignant lesions and normal tissue were 1.92 × 10(-3), 1.18 × 10(-3), 1.86 × 10(-3) s/mm(2) for DWI-STIR and 1.80 × 10(-3), 1.11 × 10(-3), 1.79 × 10(-3) s/mm(2) for SPAIR, respectively. Comparison between fat-suppression techniques showed significant differences in mean ADC values for benign (p = 0.013) and malignant lesions (p = 0.001). DWI-STIR and -SPAIR ADC cut-offs were 1.42 × 10(-3) and 1.46 × 10(-3) s/mm(2), respectively. Diagnostic performance for DWI-STIR versus SPAIR was: accuracy (81.6 versus 83.3%), area under curve (87.7 versus 89.2%), sensitivity (79.7 versus 85.1%), and specificity (85 versus 80%). Positive predictive value was similar. CONCLUSION The fat-saturation technique used in the present study may influence image quality and ADC quantification. Nevertheless, STIR and SPAIR techniques showed similar diagnostic performances, and therefore, both are suitable for use in clinical practice.
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Affiliation(s)
- Luisa Nogueira
- Department of Radiology, School of Health Technology of Porto/Polytechnic Institute of Porto (ESTSP/IPP), Rua Valente Perfeito, 4400-330, Vila Nova de Gaia, Portugal; Department of Radiology, Hospital de São João/Faculty of Medicine of Porto University (FMUP), Alameda Prof. Hernâni Monteiro, 4200-319 Porto, Portugal.
| | - Sofia Brandão
- MRI Unit, Department of Radiology, Hospital de São João, Alameda Prof. Hernani Monteiro, 4200-319 Porto, Portugal
| | - Rita G Nunes
- Institute of Biophysics and Biomedical Engineering (IBEB), Faculty of Sciences, University of Lisbon, Campo Grande, 1749-016, Lisboa, Portugal
| | - Hugo Alexandre Ferreira
- Institute of Biophysics and Biomedical Engineering (IBEB), Faculty of Sciences, University of Lisbon, Campo Grande, 1749-016, Lisboa, Portugal
| | - Joana Loureiro
- MRI Unit, Department of Radiology, Hospital de São João, Alameda Prof. Hernani Monteiro, 4200-319 Porto, Portugal
| | - Isabel Ramos
- Department of Radiology, Hospital de São João/Faculty of Medicine of Porto University (FMUP), Alameda Prof. Hernâni Monteiro, 4200-319 Porto, Portugal
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18
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Xie Y, Yu W, Fan Z, Nguyen C, Bi X, An J, Zhang T, Zhang Z, Li D. High resolution 3D diffusion cardiovascular magnetic resonance of carotid vessel wall to detect lipid core without contrast media. J Cardiovasc Magn Reson 2014; 16:67. [PMID: 25238168 PMCID: PMC4165995 DOI: 10.1186/s12968-014-0067-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2014] [Accepted: 08/12/2014] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Without the need of contrast media, diffusion-weighted imaging (DWI) has shown great promise for accurate detection of lipid-rich necrotic core (LRNC), a well-known feature of vulnerable plaques. However, limited resolution and poor image quality in vivo with conventional single-shot diffusion-weighted echo planar imaging (SS-DWEPI) has hindered its clinical application. The aim of this work is to develop a diffusion-prepared turbo-spin-echo (DP-TSE) technique for carotid plaque characterization with 3D high resolution and improved image quality. METHODS Unlike SS-DWEPI where the diffusion encoding is integrated in the EPI framework, DP-TSE uses a diffusion encoding module separated from the TSE framework, allowing for segmented acquisition without the sensitivity to phase errors. The interleaved, motion-compensated sequence was designed to enable 3D black-blood DWI of carotid arteries with sub-millimeter resolution. The sequence was tested on 12 healthy subjects and compared with SS-DWEPI for image quality, vessel wall visibility, and vessel wall thickness measurements. A pilot study was performed on 6 patients with carotid plaques using this sequence and compared with conventional contrast-enhanced multi-contrast 2D TSE as the reference. RESULTS DP-TSE demonstrated advantages over SS-DWEPI for resolution and image quality. In the healthy subjects, vessel wall visibility was significantly higher with diffusion-prepared TSE (p < 0.001). Vessel wall thicknesses measured from diffusion-prepared TSE were on average 35% thinner than those from the EPI images due to less distortion and partial volume effect (p < 0.001). ADC measurements of healthy carotid vessel wall are 1.53 ± 0.23 × 10-3 mm2/s. In patients the mean ADC measurements in the LRNC area were significantly lower (0.60 ± 0.16 × 10-3 mm2/s) than those of the fibrous plaque tissue (1.27 ± 0.29 × 10-3 mm2/s, p < 0.01). CONCLUSIONS Diffusion-prepared CMR allows, for the first time, 3D DWI of the carotid arterial wall in vivo with high spatial resolution and improved image quality over SS-DWEPI. It can potentially detect LRNC without the use of contrast agents, allowing plaque characterization in patients with renal insufficiency.
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Affiliation(s)
- Yibin Xie
- />Biomedical Imaging Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA USA
- />Department of Bioengineering, University of California, Los Angeles, CA USA
| | - Wei Yu
- />Department of Radiology, Anzhen Hospital, Capital Medical University, Beijing, China
| | - Zhaoyang Fan
- />Biomedical Imaging Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA USA
| | - Christopher Nguyen
- />Biomedical Imaging Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA USA
- />Department of Bioengineering, University of California, Los Angeles, CA USA
| | - Xiaoming Bi
- />MR R&D, Siemens Healthcare, Los Angeles, CA USA
| | - Jing An
- />MR Collaborations NE Asia, Siemens Healthcare, Beijing, China
| | - Tianjing Zhang
- />MR Collaborations NE Asia, Siemens Healthcare, Beijing, China
| | - Zhaoqi Zhang
- />Department of Radiology, Anzhen Hospital, Capital Medical University, Beijing, China
| | - Debiao Li
- />Biomedical Imaging Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA USA
- />Department of Bioengineering, University of California, Los Angeles, CA USA
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Phinikaridou A, Andia ME, Shah AM, Botnar RM. Advances in molecular imaging of atherosclerosis and myocardial infarction: shedding new light on in vivo cardiovascular biology. Am J Physiol Heart Circ Physiol 2012; 303:H1397-410. [PMID: 23064836 DOI: 10.1152/ajpheart.00583.2012] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Molecular imaging of the cardiovascular system heavily relies on the development of new imaging probes and technologies to facilitate visualization of biological processes underlying or preceding disease. Molecular imaging is a highly active research discipline that has seen tremendous growth over the past decade. It has broadened our understanding of oncologic, neurologic, and cardiovascular diseases by providing new insights into the in vivo biology of disease progression and therapeutic interventions. As it allows for the longitudinal evaluation of biological processes, it is ideally suited for monitoring treatment response. In this review, we will concentrate on the major accomplishments and advances in the field of molecular imaging of atherosclerosis and myocardial infarction with a special focus on magnetic resonance imaging.
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Affiliation(s)
- Alkystis Phinikaridou
- Division of Imaging Science and Biomedical Engineering, King's College London, United Kingdom.
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20
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The immunologic injury composite with balloon injury leads to dyslipidemia: a robust rabbit model of human atherosclerosis and vulnerable plaque. J Biomed Biotechnol 2012; 2012:249129. [PMID: 22988422 PMCID: PMC3441062 DOI: 10.1155/2012/249129] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2012] [Revised: 07/25/2012] [Accepted: 07/30/2012] [Indexed: 11/25/2022] Open
Abstract
Atherosclerosis is a condition in which a lipid deposition, thrombus formation, immune cell infiltration, and a chronic inflammatory response, but its systemic study has been hampered by the lack of suitable animal models, especially in herbalism fields. We have tried to perform a perfect animal model that completely replicates the stages of human atherosclerosis. This is the first combined study about the immunologic injury and balloon injury based on the cholesterol diet. In this study, we developed a modified protocol of the white rabbit model that could represent a novel approach to studying human atherosclerosis and vulnerable plaque.
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21
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Leitão HS, Doblas S, d'Assignies G, Garteiser P, Daire JL, Paradis V, Geraldes CFGC, Vilgrain V, Van Beers BE. Fat deposition decreases diffusion parameters at MRI: a study in phantoms and patients with liver steatosis. Eur Radiol 2012; 23:461-7. [PMID: 22935901 DOI: 10.1007/s00330-012-2626-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2012] [Revised: 06/19/2012] [Accepted: 06/29/2012] [Indexed: 02/07/2023]
Abstract
PURPOSE Assess the effect of fat deposition on the MRI diffusion coefficients in lipid emulsion-based phantoms and patients with proven isolated liver steatosis. MATERIALS AND METHODS Diffusion-weighted MRI with 11 b values from 0-500 s/mm(2) was performed in phantoms (fat fractions 0-18 %) with and without fat suppression and in 19 patients with normal liver (n = 14) or isolated liver steatosis (n = 5) proven by histopathology. The apparent, pure and perfusion-related diffusion coefficients and the perfusion fraction were measured. Spearman correlation coefficient and Mann-Whitney U test were used for comparisons. RESULTS A strong correlation between the apparent and pure diffusion coefficients and fat fractions was seen in phantoms. The pure diffusion coefficient decreased significantly in patients with liver steatosis (0.96 ± 0.16 × 10(-3) mm(2)/s versus 1.18 ± 0.09 × 10(-3) mm(2)/s in normal liver, P = 0.005), whereas the decrease in apparent diffusion coefficient did not reach statistical significance (1.26 ± 0.25 × 10(-3) mm(2)/s versus 1.41 ± 0.14 × 10(-3) mm(2)/s in normal liver, P = 0.298). CONCLUSIONS Fat deposition decreases the apparent and pure diffusion coefficients in lipid emulsion-based phantoms and patients with isolated liver steatosis proven by histopathology.
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Affiliation(s)
- Helena S Leitão
- Center for Neuroscience and Cell Biology, PhD Program in Experimental Biology and Biomedicine, University of Coimbra, Coimbra, Portugal.
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22
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Yang E, Vargas JD, Bluemke DA. Understanding the genetics of coronary artery disease through the lens of noninvasive imaging. Expert Rev Cardiovasc Ther 2012; 10:27-36. [PMID: 22149524 PMCID: PMC3482161 DOI: 10.1586/erc.11.175] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Coronary artery disease is a common condition with a known heritable component that has spurred interest in genetic research for decades, resulting in a handful of candidate genes and an appreciation for the complexity of its genetic contributions. Recent advances in sequencing technologies have resulted in large-scale association studies, possibly adding to our current understanding of the genetics of coronary artery disease. Sifting through the statistical noise, however, requires the selection of effective phenotypic markers. New imaging technologies have improved our ability to detect subclinical atherosclerosis in a safe and reproducible manner in large numbers of patients. In this article, we propose that advances in imaging technology have generated improved phenotypic markers for genetic association studies of coronary artery disease.
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Affiliation(s)
| | - Jose D Vargas
- Radiology and Imaging Sciences, National Institutes of Health
| | - David A Bluemke
- Radiology and Imaging Sciences, National Institutes of Health, 10 Center Dr, Rm 10/1C355, Bethesda, MD, 20892
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23
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Degnan AJ, Gillard JH. Improving atherosclerosis risk assessment: looking beyond plaque accumulation to imaging of embolization and healing. FUTURE NEUROLOGY 2012. [DOI: 10.2217/fnl.11.60] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Cerebrovascular and cardiovascular diseases constitute the most substantial disease burden worldwide and are only increasing in importance. Understanding how individuals with atherosclerosis may be better assessed for risk of stroke and myocardial infarction will have immense importance in deciding on therapeutic options. Carotid atherosclerosis is frequently portrayed as an orderly progression from asymptomatic plaque formation that enlarges with aging and culminates in either stable, calcified plaque or vulnerable, ruptured and inflamed plaque. New evidence suggests that atherosclerosis is better described as an equilibrium between synthetic and degradative processes. Putatively, plaques heal and decrease in size through processes such as efferocytosis in individuals unlikely to experience symptoms, whereas individuals who experience symptoms lack reparative mechanisms. Present clinically employed imaging strategies overlook plaque healing mechanisms. Other approaches that examine the downstream effects of plaque, rather than static plaque measurement, such as ultrasound emboli signal detection may address the gap between plaque that is vulnerable in appearance and that which is actually likely to cause symptoms. To ascertain the clinical risk of atherosclerosis optimally, both sides of the equation must be examined instead of relying on a unidirectional accumulative approach to atherosclerosis.
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Affiliation(s)
| | - Jonathan H Gillard
- Department of Radiology, Addenbrooke’s Hospital, University of Cambridge, Box 218, Hills Road, Cambridge, UK
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24
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Qiao Y, Hallock KJ, Hamilton JA. Magnetization transfer magnetic resonance of human atherosclerotic plaques ex vivo detects areas of high protein density. J Cardiovasc Magn Reson 2011; 13:73. [PMID: 22107813 PMCID: PMC3278375 DOI: 10.1186/1532-429x-13-73] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2011] [Accepted: 11/22/2011] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Proteins are major plaque components, and their degradation is related to the plaque instability. We sought to assess the feasibility of magnetization transfer (MT) magnetic resonance (MR) for identifying fibrin and collagen in carotid atherosclerotic plaques ex vivo. METHODS Human carotid artery specimens (n = 34) were obtained after resection from patients undergoing endarterectomy. MR was completed within 12 hr after surgery on an 11.7T MR microscope prior to fixation. Two sets of T1W spoiled gradient echo images were acquired with and without the application of a saturation pulse set to 10 kHz off resonance. The magnetization transfer ratio (MTR) was calculated, and the degree of MT contrast was correlated with histology. RESULTS MT with appropriate calibration clearly detected regions with high protein density, which showed a higher MTR (thick fibers (collagen type I) (54 ± 8%)) compared to regions with a low amount of protein including lipid (46 ± 8%) (p = 0.05), thin fibers (collagen type III) (11 ± 6%) (p = 0.03), and calcification (6.8 ± 4%) (p = 0.02). Intraplaque hemorrhage (IPH) with different protein density demonstrated different MT effects. Old (rich in protein debris) and recent IPH (rich in fibrin) had a much higher MTR 69 ± 6% and 55 ± 9%, respectively, compared to fresh IPH (rich in intact red blood cells)(9 ± 3%). CONCLUSIONS MT MR enhances plaque tissue contrast and identifies the protein-rich regions of carotid artery specimens. The additional information from MTR of IPH may provide important insight into the role of IPH on plaque stability, evolution, and the risk for future ischemic events.
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Affiliation(s)
- Ye Qiao
- Department of Physiology and Biophysics, Boston University School of Medicine, 715 Albany Street (W302), Boston, MA 02118-2526, USA
| | - Kevin J Hallock
- Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, MA, USA
| | - James A Hamilton
- Department of Physiology and Biophysics, Boston University School of Medicine, 715 Albany Street (W302), Boston, MA 02118-2526, USA
- Department of Biomedical Engineering, Boston University, Boston, MA, USA
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25
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Kim SE, Treiman GS, Roberts JA, Jeong EK, Shi X, Hadley JR, Parker DL. In vivo and ex vivo measurements of the mean ADC values of lipid necrotic core and hemorrhage obtained from diffusion weighted imaging in human atherosclerotic plaques. J Magn Reson Imaging 2011; 34:1167-75. [DOI: 10.1002/jmri.22736] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2010] [Accepted: 07/15/2011] [Indexed: 11/10/2022] Open
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26
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Anderson SW, Soto JA, Milch HN, Ozonoff A, O'Brien M, Hamilton JA, Jara HJ. Effect of disease progression on liver apparent diffusion coefficient values in a murine model of NASH at 11.7 Tesla MRI. J Magn Reson Imaging 2011; 33:882-8. [PMID: 21448953 DOI: 10.1002/jmri.22481] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
PURPOSE To evaluate the apparent diffusion coefficient (ADC) values of liver in a murine model of non-alcoholic steatohepatitis using 11.7 Tesla (T) MRI. MATERIALS AND METHODS This animal study was IACUC approved. Seventeen male C57BL/6 mice were divided into control (n = 3) and experimental groups (n = 14) fed a methionine-deficient choline-deficient (MCD) diet to induce steatohepatitis. Livers underwent ex vivo diffusion-weighted MR imaging and ADC maps were calculated. A pathologist determined subjective scores of steatosis, classified from 0 to 3. Digital image analysis was used to determine percentage areas of steatosis. Graphs comparing ADC to subjective and digital image analysis (DIA) determinations of steatosis were plotted. RESULTS Subjective assessments of steatosis ranged up to values of 3 and DIA determined areas of steatosis to range up to approximately 16%. ADC values approximated 800 × 10(-6) mm(2) /s (range, 749-811 × 10(-6) mm(2) /s, mean 786 × 10(-6) mm(2) /s) in controls and 500 × 10(-6) mm(2) /s (range, 478-733 × 10(-6) mm(2) /s, mean 625 × 10(-6) mm(2) /s) in experimental mice. Moderate correlation between ADC and subjective scores of steatosis (R = -0.56) was observed. Strong correlation between ADC values and percentage areas of steatosis was between ADC values and percentage areas of steatosis was observed greater (R = -0.81) and very strong correlation was observed with the exclusion of a single outlying data point (R = -0.91). CONCLUSION Based on the comparison of ADC values and steatosis determinations by DIA, increasing degrees of steatosis are seen to result in decreased hepatic ADC values.
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Affiliation(s)
- Stephan W Anderson
- Boston University Medical Center, Department of Radiology, Boston, MA, USA.
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27
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Vancraeynest D, Pasquet A, Roelants V, Gerber BL, Vanoverschelde JLJ. Imaging the vulnerable plaque. J Am Coll Cardiol 2011; 57:1961-79. [PMID: 21565634 DOI: 10.1016/j.jacc.2011.02.018] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2011] [Revised: 02/09/2011] [Accepted: 02/15/2011] [Indexed: 12/27/2022]
Abstract
Cardiovascular diseases are still the primary causes of mortality in the United States and in Western Europe. Arterial thrombosis is triggered by a ruptured atherosclerotic plaque and precipitates an acute vascular event, which is responsible for the high mortality rate. These rupture-prone plaques are called "vulnerable plaques." During the past decades, much effort has been put toward accurately detecting the presence of vulnerable plaques with different imaging techniques. In this review, we provide an overview of the currently available invasive and noninvasive imaging modalities used to detect vulnerable plaques. We will discuss the upcoming challenges in translating these techniques into clinical practice and in assigning them their exact place in the decision-making process.
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Affiliation(s)
- David Vancraeynest
- Pôle de Recherche Cardiovasculaire, Institut de Recherche Expérimentale et Cliniques, Université Catholique de Louvain, Brussels, Belgium
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28
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High-resolution MRI of carotid plaque with a neurovascular coil and contrast-enhanced MR angiography: one-stop shopping for the comprehensive assessment of carotid atherosclerosis. AJR Am J Roentgenol 2011; 196:1164-71. [PMID: 21512087 DOI: 10.2214/ajr.10.4751] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE The objective of our study was to assess a protocol of study of carotid atherosclerosis coupling vascular wall imaging and luminal imaging in the same examination and to evaluate the accuracy of high-resolution MRI with a neurovascular coil in carotid plaque characterization. SUBJECTS AND METHODS Thirty-two consecutive patients with 34 carotid artery stenoses were prospectively enrolled. MRI was performed on a 1.5-T unit. Plaque assessment was performed starting with a diffusion-weighted sequence and followed by a fat-suppressed T1-weighted sequence; after contrast-enhanced MR angiography (CE-MRA), all patients were evaluated with a T1-weighted 3D high-resolution sequence. Carotid plaques were classified as type A, having a large lipid-necrotic core; type B, being a complex fibrotic-calcified plaque with soft content (mixed plaque); or type C, being a fibrotic-calcified plaque (hard). Additional features indicative of vulnerable plaque such as intraplaque hemorrhage (IPH), ulceration, and severe stenosis were registered. MR findings were compared with surgical specimens. RESULTS MRI correctly identified 11 of 13 type A, eight of 11 type B, and eight of 10 type C plaques (sensitivity, 84.6%, 72.7%, and 80%, respectively). In the identification of lipid-necrotic core plaque, MRI showed a sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 84.6%, 100%, 100%, and 91.3%, respectively (κ = 0.87). For reordering all plaques in two groups (i.e., soft vs nonsoft) in the identification of soft plaques, MRI had a sensitivity, specificity, PPV, and NPV of 83.3%, 80%, 90.9%, and 66.7%, respectively (κ = 0.59). IPH, ulcers, and severe stenosis were detected in eight of eight, 11 of 13, and 25 of 25 cases, respectively. CONCLUSION In patients with carotid atherosclerosis, ongoing CE-MRA with a neurovascular coil for the simultaneous detection of unstable plaques is feasible. Our MR protocol accurately identifies the major features of vulnerable plaque.
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Abstract
Vessel wall imaging of large vessels has the potential to identify culprit atherosclerotic plaques that lead to cardiovascular events. Comprehensive assessment of atherosclerotic plaque size, composition, and biological activity is possible with magnetic resonance imaging (MRI). Magnetic resonance imaging of the atherosclerotic plaque has demonstrated high accuracy and measurement reproducibility for plaque size. The accuracy of in vivo multicontrast MRI for identification of plaque composition has been validated against histological findings. Magnetic resonance imaging markers of plaque biological activity such as neovasculature and inflammation have been demonstrated. In contrast to other plaque imaging modalities, MRI can be used to study multiple vascular beds noninvasively over time. In this review, we compare the status of in vivo plaque imaging by MRI to competing imaging modalities. Recent MR technological improvements allow fast, accurate, and reproducible plaque imaging. An overview of current MRI techniques required for carotid plaque imaging including hardware, specialized pulse sequences, and processing algorithms are presented. In addition, the application of these techniques to coronary, aortic, and peripheral vascular beds is reviewed.
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Young VE, Patterson AJ, Sadat U, Bowden DJ, Graves MJ, Tang TY, Priest AN, Skepper JN, Kirkpatrick PJ, Gillard JH. Diffusion-weighted magnetic resonance imaging for the detection of lipid-rich necrotic core in carotid atheroma in vivo. Neuroradiology 2010; 52:929-36. [PMID: 20358366 DOI: 10.1007/s00234-010-0680-y] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2009] [Accepted: 03/05/2010] [Indexed: 12/31/2022]
Affiliation(s)
- Victoria Eleanor Young
- University Department of Radiology, Addenbrooke's Hospital, Box 218, Hills Road, Cambridge, CB2 0QQ, UK.
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Rybicki FJ, Mitsouras D, Owens CD, Whitmore A, Gerhard-Herman M, Wake N, Cai T, Zhou Q, Conte MS, Creager MA, Mulkern RV. Multi-contrast high spatial resolution black blood inner volume three-dimensional fast spin echo MR imaging in peripheral vein bypass grafts. Int J Cardiovasc Imaging 2010; 26:683-91. [PMID: 20333469 DOI: 10.1007/s10554-010-9621-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2010] [Accepted: 03/09/2010] [Indexed: 01/20/2023]
Abstract
The purpose of this study is to primarily evaluate the lumen area and secondarily evaluate wall area measurements of in vivo lower extremity peripheral vein bypass grafts patients using high spatial resolution, limited field of view, cardiac gated, black blood inner volume three-dimensional fast spin echo MRI. Fifteen LE-PVBG patients prospectively underwent ultrasound followed by T1-weighted and T2-weighted magnetic resonance (MR) imaging. Lumen and vessel wall areas were measured by direct planimetry. For graft lumen areas, T1- and T2-weighted measurements were compared with ultrasound. For vessel wall areas, differences between T1- and T2-weighted measurements were evaluated. There was no significant difference between ultrasound and MR lumen measurements, reflecting minimal MR blood suppression artifact. Graft wall area measured from T1-weighted images was significantly larger than that measured from T2-weighted images (P < 0.001). The mean of the ratio of T1- versus T2-weighted vessel wall areas was 1.59 (95% CI: 1.48-1.69). The larger wall area measured on T1-weighted images was due to a significantly larger outer vessel wall boundary. Very high spatial resolution LE-PVBG vessel wall MR imaging can be performed in vivo, enabling accurate measurements of lumen and vessel wall areas and discerning differences in those measures between different tissue contrast weightings. Vessel wall area differences suggest that LE-PVBG vessel wall tissues produce distinct signal characteristics under T1 and T2 MR contrast weightings.
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Affiliation(s)
- Frank J Rybicki
- Applied Imaging Science Laboratory, Department of Radiology, Brigham and Women's Hospital, Boston, MA, USA.
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Kim SE, Jeong EK, Shi XF, Morrell G, Treiman GS, Parker DL. Diffusion-weighted imaging of human carotid artery using 2D single-shot interleaved multislice inner volume diffusion-weighted echo planar imaging (2D ss-IMIV-DWEPI) at 3T: diffusion measurement in atherosclerotic plaque. J Magn Reson Imaging 2010; 30:1068-77. [PMID: 19856440 DOI: 10.1002/jmri.21944] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
PURPOSE To determine if 2D single-shot interleaved multislice inner volume diffusion-weighted echo planar imaging (ss-IMIV-DWEPI) can be used to obtain quantitative diffusion measurements that can assist in the identification of plaque components in the cervical carotid artery. MATERIALS AND METHODS The 2D ss-DWEPI sequence was combined with interleaved multislice inner volume region localization to obtain diffusion weighted images with 1 mm in-plane resolution and 2 mm slice thickness. Eleven subjects, six of whom have carotid plaque, were studied with this technique. The apparent diffusion coefficient (ADC) images were calculated using DW images with b = 10 s/mm(2) and b = 300 s/mm(2). RESULTS The mean ADC measurement in normal vessel wall of the 11 subjects was 1.28 +/- 0.09 x 10(-3) mm(2)/s. Six of the 11 subjects had carotid plaque and ADC measurements in plaque ranged from 0.29 to 0.87 x 10(-3) mm(2)/s. Of the 11 common carotid artery walls studied (33 images), at least partial visualization of the wall was obtained in all ADC images, more than 50% visualization in 82% (27/33 images), and full visualization in 18% (6/33 images). CONCLUSION 2D ss-IMIV-DWEPI can perform diffusion-weighted carotid magnetic resonance imaging (MRI) in vivo with reasonably high spatial resolution (1 x 1 x 2 mm(3)). ADC values of the carotid wall and plaque are consistent with similar values obtained from ex vivo endarterectomy specimens. The spread in ADC values obtained from plaque indicate that this technique could form a basis for plaque component identification in conjunction with other MRI/MRA techniques.
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Affiliation(s)
- Seong-Eun Kim
- Department of Radiology, Utah Center for Advanced Imaging Research, Salt Lake City, Utah 84108, USA.
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Mitsouras D, Owens CD, Conte MS, Ersoy H, Creager MA, Rybicki FJ, Mulkern RV. In vivo differentiation of two vessel wall layers in lower extremity peripheral vein bypass grafts: application of high-resolution inner-volume black blood 3D FSE. Magn Reson Med 2009; 62:607-15. [PMID: 19449380 DOI: 10.1002/mrm.22037] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Lower extremity peripheral vein bypass grafts (LE-PVBG) imaged with high-resolution black blood three-dimensional (3D) inner-volume (IV) fast spin echo (FSE) MRI at 1.5 Tesla possess a two-layer appearance in T1W images while only the inner layer appears visible in the corresponding T2W images. This study quantifies this difference in six patients imaged 6 months after implantation, and attributes the difference to the T(2) relaxation rates of vessel wall tissues measured ex vivo in two specimens with histologic correlation. The visual observation of two LE-PVBG vessel wall components imaged in vivo is confirmed to be significant (P < 0.0001), with a mean vessel wall area difference of 6.8 +/- 2.7 mm(2) between contrasts, and a ratio of T1W to T2W vessel wall area of 1.67 +/- 0.28. The difference is attributed to a significantly (P < 0.0001) shorter T(2) relaxation in the adventitia (T(2) = 52.6 +/- 3.5 ms) compared with the neointima/media (T(2) = 174.7 +/- 12.1 ms). Notably, adventitial tissue exhibits biexponential T(2) signal decay (P < 0.0001 vs monoexponential). Our results suggest that high-resolution black blood 3D IV-FSE can be useful for studying the biology of bypass graft wall maturation and pathophysiology in vivo, by enabling independent visualization of the relative remodeling of the neointima/media and adventitia.
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Affiliation(s)
- Dimitris Mitsouras
- Department of Radiology, Applied Imaging Science Laboratory, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA.
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Abstract
This review examines the state of the art in vessel wall imaging by magnetic resonance imaging (MRI) with an emphasis on the biomechanical assessment of atherosclerotic plaque. Three areas of advanced techniques are discussed. First, alternative contrast mechanisms, including susceptibility, magnetization transfer, diffusion, and perfusion, are presented as to how they facilitate accurate determination of plaque constituents underlying biomechanics. Second, imaging technologies including hardware and sequences, are reviewed as to how they provide the resolution and signal-to-noise ratio necessary for determining plaque structure. Finally, techniques for combining MRI data into an overall assessment of plaque biomechanical properties, including wall shear stress and internal plaque strain, are presented. The paper closes with a discussion of the extent to which these techniques have been applied to different arteries commonly targeted by vessel wall MRI.
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Affiliation(s)
- William S Kerwin
- Department of Radiology, University of Washington, Seattle, WA 98109, USA.
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Abstract
Atherothrombosis is a systemic disease of the arterial wall that affects the carotid, coronary, and peripheral vascular beds, and the aorta. This condition is associated with complications such as stroke, myocardial infarction, and peripheral vascular disease, which usually result from unstable atheromatous plaques. The study of atheromatous plaques can provide useful information about the natural history and progression of the disease, and aid in the selection of appropriate treatment. Plaque imaging can be crucial in achieving this goal. In this Review, we focus on the various noninvasive imaging techniques that are being used for morphological and functional assessment of carotid atheromatous plaques in the clinical setting.
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Qiao Y, Farber A, Semaan E, Hamilton JA. Images in cardiovascular medicine. Healing of an asymptomatic carotid plaque ulceration. Circulation 2008; 118:e147-8. [PMID: 18765382 DOI: 10.1161/circulationaha.108.764779] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Ye Qiao
- Department of Physiology and Biophysics, Boston University School of Medicine, 715 Albany St, W302, Boston, MA, USA
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High-resolution multicontrast-weighted MR imaging from human carotid endarterectomy specimens to assess carotid plaque components. Eur Radiol 2008; 18:2912-21. [DOI: 10.1007/s00330-008-1091-x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2007] [Revised: 05/13/2008] [Accepted: 05/24/2008] [Indexed: 01/19/2023]
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Abstract
OBJECTIVES The Computer-Aided System for CArdiovascular Disease Evaluation (CASCADE) has been developed for streamlined, automated analysis of carotid artery magnetic resonance imaging to measure atherosclerotic plaque burden and composition in vivo. The purpose of this investigation was to assess the performance of CASCADE compared with manual outlining. METHODS Magnetic resonance images were obtained from 26 subjects with 16% to 79% carotid artery stenosis by duplex ultrasound who were imaged twice in a 2-week period with a multiple-slice, multiple-contrast magnetic resonance imaging protocol as part of the Outcome of Rosuvastatin treatment on carotid artery atheroma: a magnetic resonance Imaging ObservatioN trial. Manual outlining was used to identify the boundaries of the lumen, wall, necrotic core (NC), and calcifications. After 6 months, the analysis was repeated using CASCADE. For each data set, the contours were used to compute the maximal normalized wall index (NWI; wall area divided by total vessel area), maximal wall thickness (WT), and the average NC and calcified (CA) areas per slice. Agreement between manual and automated reviews and the scan-scan measurement reproducibilities were evaluated. RESULTS Pearson correlation between manual and automated analyses was 0.94 for maximal NWI, 0.86 for maximal WT, 0.84 for NC, and 0.96 for CA. Intraclass correlation coefficients for manual and automated analyses were 0.90 and 0.97 for maximal NWI, 0.89 and 0.95 for maximal WT, 0.95 and 0.87 for NC, and 0.96 and 0.94 for CA, respectively. CONCLUSIONS Automated analysis tools are capable of providing accurate and reproducible measurements of carotid atherosclerotic burden and composition when compared with manually outlined results.
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