ISMRM 21st Annual Meeting & Exhibition 20-26 April 2013 Salt Lake City, Utah, USA

Vessel Wall Imaging
Friday 26 April 2013
Room 355 EF  10:30 - 12:30 Moderators: Zahi A. Fayad, M. Eline Kooi

10:30 0874.   Introduction
Zahi A. Fayad


10:42 0875.   MRI Screening for Lipid-Rich Necrotic Core in Multicenter Clinical Trials of Lipid-Lowering Therapy
Niranjan Balu1, Daniel S. Hippe1, Jie Sun1, Dongxiang Xu1, Thomas Hatsukami2, and Chun Yuan1
1Radiology, University of Washington, Seattle, Washington, United States, 2Surgery, University of Washington, Seattle, Washington, United States

The size of the lipid-rich necrotic core (LRNC) in atherosclerotic plaque is an early indicator of efficacy in lipid lowering therapy. Clinical trials using LRNC as the primary endpoint require highly specific screening for subjects with LRNC in order to be cost-effective. We describe the first multicenter MRI study using LRNC as the primary study endpoint with a tiered ultrasound-MRI screening. A probabilistic model derived using sensitivity and specificity of maximum wall thickness (maxWT) in detecting subjects with LRNC shows that total imaging costs can be reduced by 10% while increasing specificity by adding maxWT to the tiered ultrasound-MRI screening.

10:54 0876.   
Black-Blood Dynamic Contrast-Enhanced Coronary Artery Wall MRI: A Potential Tool for Kinetic-Modeling-Based Wall Inflammation Assessment
Zhaoyang Fan1, Jingsi Xie1, Yi He2, Yutaka Natsuaki3, Ning Jin4, Daniel S. Berman5, and Debiao Li5
1Cedars-Sinai Medical Center, Los Angeles, California, United States, 2Radiology, Beijing Anzhen Hospital, Capital Medical University, Beijing, China, 3Siemens Healthcare, Los Angeles, California, United States, 4Siemens Healthcare, Columbus, OH, United States, 5Cedars-Sinai Medical Center, Los Angeles, CA, United States

Dynamic gadolinium contrast-enhanced (DCE) vessel wall MRI has recently been used to characterize the extent of inflammation in carotid plaques. However, no studies have shown its feasibility in coronary artery wall, presumably due to the technical challenges in imaging such a constantly-moving and ultra-small structure and visually distinguishing the wall from the hyperintense lumen with conventional DCE techniques. The present work aimed to develop a black-blood navigator-gated ECG-triggered T1-weighted sequence for DCE MRI of coronary vessel wall. The sequence allows acquisition of high-spatial-resolution bright blood and black blood images in an interleaved fashion, regardless of time-varying T1 of blood.

11:06 0877.   
Validation of 3D Multi-Contrast Black Blood Sequences with Large Coverage for One-Stop Neurovascular Screening
Zechen Zhou1, Rui Li1, Xihai Zhao1, Le He1, and Chun Yuan1,2
1Department of Biomedical Engineering, Tsinghua University, Beijing, China, 2Department of Radiology, University of Washington (Seattle), Seattle, Washington, United States

Multi-contrast Black Blood (BB) MRI can effectively detect and measure the atherosclerotic plaque morphology and components. Currently wide used 2D T1W and T2W BB imaging sequences might give rise to missed or false diagnosis due to the limitations of the lesion detection range and partial volume effect. In this study, we suppose to apply the recently proposed 3D multi-contrast BB techniques including MERGE, VISTA and SNAP to cover the major intracranial and entire extracranial arteries and we found that the blood suppression effectiveness and image quality for diagnosis in this large-coverage situation can fully support for the one-stop neurovascular screening.

11:18 0878.   3D Dark Blood Cine Magnetic Resonance Imaging of the Carotid Arteries
Ioannis Koktzoglou1,2, Tina Desai2,3, and NavYash Gupta2,3
1Radiology, NorthShore University HealthSystem, Evanston, Illinois, United States, 2The University of Chicago Pritzker School of Medicine, Chicago, IL, United States, 3Vascular Surgery, NorthShore University HealthSystem, Skokie, IL, United States

A three-dimensional dark-blood cine magnetic resonance imaging pulse sequence capable of displaying the human arterial wall is described. The method is applied to the carotid arteries and demonstrates the ability to display the arterial wall and its motion with fine temporal resolution and submillimeter spatial resolution over the cardiac cycle.

11:30 0879.   Assessment of Carotid Atherosclerotic Disease Using 3D Fast Black Blood MR Imaging: Comparison with DSAnull
Huilin Zhao1, Jinnan Wang2,3, Xihai Zhao4, Xiaosheng Liu1, Ye Cao1, Jianrong Xu1, Daniel S. Hippe3, and Chun Yuan3
1Radiology, Renji hospital, Shanghai Jiao Tong Univesity School of Medicine, Shanghai, Shanghai, China, 2Philips Research North America, Seattle, WA, United States, 3Radiology, University of Washington, Seattle, WA, United States, 4Center for Biomedical Imaging Research,Tsinghua University School of Medicine, Beijing, Beijing, China

It has been shown that fast 3D black-blood (BB) MR sequence is capable of delineating both luminal and outer wall boundaries of bilateral carotid arteries. This study sought to determine the accuracy of this technique at quantifying carotid atherosclerotic disease compared to DSA in patients with at least 50% luminal stenosis. Our key findings are that very good agreement was found between 3D BB-MRI and DSA in assessing carotid luminal stenosis and ulceration. However, carotid stenotic lesion length measurements by 3D BB-MRI were significantly longer than that measured by DSA. These findings indicate that 3D BB-MRI has the potential to become an alternative imaging approach in evaluating the severity of carotid atherosclerotic disease.

11:42 0880.   3D Carotid Wall T1 Quantification Using Variable Flip Angle 3D Merge with Steady-State Recovery
Bram F. Coolen1, Dennis F.R. Heijtel1, Wouter V. Potters1, and Aart J. Nederveen1
1Department of Radiology, Academic Medical Center Amsterdam, Amsterdam, Netherlands

A novel method for 3D carotid artery T1 quantification is presented, based on combining 3D Merge black-blood imaging with a variable flip angle T1 analysis. The application of a dummy pulse train following read-out ensures steady-state conditions for the acquired data, which is needed for correct T1 estimation. Simulations, phantom and in vivo measurements were performed to assess the feasibility of the proposed method.

11:54 0881.   Time Resolved Coronary Vessel Wall MRI Using Phase-Sensitive DIR (TRAPD)
Khaled Z. Abd-Elmoniem1, Ahmed M. Gharib1, and Roderic I. Pettigrew2
1National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, MD, United States, 2National Institute of Biomedical Imaging and Bioengineering, NIH, Bethesda, MD, United States

Technical challenges still hinder coronary wall imaging for routine clinical utilization. The purpose of this study was to develop a time-resolved acquisition of phase-sensitive DIR (TRAPD) coronary vessel wall MRI that overcomes the loss of the orthogonality due to uncompensated residual motions

12:06 0882.   Motion, Resolution and Noise Thresholds for the Accurate Classification of Human Coronary Atherosclerotic Plaque by MRI
Paula Montesinos1,2, Himanshu Bhat3, Guangping Dai4, Manuel Desco1,2, Elfar Adalsteinsson5, Reza Nezafat6, and David E. Sosnovik5
1Departamento de Bioingeniería e Ingeniería Aeroespacial, Universidad Carlos III de Madrid, Madrid, Spain, 2Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain, 3Siemens Medical Solutions, Charlestown, MA, United States, 4Massachusetts General Hospital, Charlestown, MA, United States, 5Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, United States, 6Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States

The requirements for the accurate classification of human coronary atherosclerotic plaque by MRI in vivo remain unknown. We aimed here to reconstruct a high resolution ex vivo “ground truth” dataset of human coronary atherosclerotic plaques with varying degrees of spatial resolution, SNR and motion. Our results indicate that a spatial resolution of 0.5 mm, SNR > 10 and motion correction in all 3 directions are needed for in vivo MRI of coronary plaque. We further show that the acquisition of the central 10-15% of k-space during a motion-free breathold could reduce artifacts even further.

12:18 0883.   Theragnostic Imaging of Micelle-Mediated Rosiglitazone Delivery to Atherosclerotic Plaques
Brigit den Adel1,2, Sandra Bovens3, Ernst Suidgeest4, Gustav J. Strijkers5, Gerard Pasterkamp3, Robert E. Poelmann2, and Louise van der Weerd4,6
1Pathology, Amsterdam Medical Center, Amsterdam, Netherlands, 2Anatomy, Leiden University Medical Center, Leiden, Netherlands, 3Cardiology, University Medical Center Utrecht, Utrecht, Netherlands, 4Radiology, Leiden University Medical Center, Leiden, Netherlands, 5Biomedical Engineering, Eindhoven University of Technology, Eindhoven, Netherlands,6Human Genetics, Leiden University Medical Center, Leiden, Netherlands

This study shows the theragnostic imaging and treatment of atherosclerotis in ApoE-/- and ApoE-/-eNOS-/- mice. The application of non-invasive molecular imaging to monitor drug delivery and therapeutic responses. Rosiglitazone was incorporated in micelles to improve targeting to plaques and reduce the well-known side effects of this drug. Atherosclerotic lesions were reduced after micelle-mediated rosiglitazone therapy, while avoiding the negative side effects associated with conventional rosiglitazone treatment.