Coronary MRA & Vessel Wall Imaging (Coronary & Non-coronary)
Click on to view the abstract pdf. Click on to view the recorded presentation.
Tuesday 8 May 2012
Room 210-211  16:00 - 18:00 Moderators: Jeroen Hendrikse, M. Eline Kooi

16:00 0315.   
Combined coronary and late-enhanced viability imaging using 3.0T whole-heart coronary MRA for delineation of the etiology of left ventricular dysfunction
Qi Yang1, Kuncheng Li1, Xiangying Du1, Xiaoming Bi2, Yu Zhang3, Jing An3, and Debiao Li4
1Xuanwu Hospital, Beijing, China, 2Siemens Medical Solutions USA, 3Siemens Healthcare, MR Collaboration NE Asia, 4Cedars-Sinai Medical Center and UCLA

The major advantage of 3.0T whole-heart coronary MRA (CMRA) using a continuous gadolinium infusion is to combine lumenographic information and 3D myocardial viability in the same settings with patterns similar to those obtained by 2D-LGE (late Gd-enhanced) techinique. This suggests a potential of this technique to assist in recognizing the etiology of patients with left ventricular dysfunction (LVD) which is essential for the risk stratification and treatment selection.

16:12 0316.   Water/Fat resolved Whole-Heart Dixon Coronary MRA: An Initial Comparison
Peter Börnert1, Peter Koken1, Kay Nehrke1, Holger Eggers1, and Peter Ostendorf2
1Philips Research Laboratories, Hamburg, Germany, 2Centre of Preventive Medicine, Marienkrankenhaus, Hamburg, Germany

To improve coronary vessel visualization in whole heart CMRA, fat suppression is typically applied. However, recent studies showed that cardiac fat can also have diagnostic value. To address also the fat information two-point Dixon protocols have been proposed to replace fat-sat based protocols for CMRA with no scan time penalty. In this pilot study water / fat-separated Dixon protocols are compared to conventional whole heart CMRA imaging protocols used in clinical practice. It has been found in this patient study that two-point Dixon protocols can potentially replace conventional fat-sat-based protocols for CMRA.

16:24 0317.   
A Novel Slice-selective Implementation of the Adiabatic T2Prep Sequence Objectively Improves Coronary Artery Conspicuity
Sahar Soleimanifard1, Michael Schär1,2, Allison G. Hays1, Jerry L. Prince1, Robert G. Weiss1, and Matthias Stuber1,3
1Johns Hopkins University, Baltimore, MD, United States, 2Philips Healthcare, Cleveland, OH, United States, 3University of Lausanne, Lausanne, Switzerland

In non-contrast coronary MRA, the T2Prep sequence has been widely used for contrast enhancement between the coronary blood-pool and the myocardium. This non-selective sequence, however, results in a reduced steady-state magnetization of the inflowing blood, and consequently a penalty in SNR. We hypothesize that a slice-selective variant of this pre-pulse would leave the magnetization of blood outside the imaged volume unaffected, and thereby minimize SNR penalty for inflowing blood. In this work, we implemented a slice-selective T2Prep and assessed the SNR gain and vessel conspicuity quantitatively using an automatic framework for vessel centerline tracking and boundary segmentation.

16:36 0318.   
i-T2prep: Flow-independent 3D whole heart vessel wall imaging using an interleaved T2-preparation acquisition
Marcelo E Andia1, Markus Henningsson1, Tarique Hussain1, Alkystis Phinikaridou1, Gerald Greil1, and Rene M Botnar1
1Division of Imaging Sciences and Biomedical Engineering, Kings College London, London, London, United Kingdom

We present a novel technique for flow-independent vessel wall imaging based on the differences in T2-relaxation time of arterial blood and surrounding tissues using a T2prep prepulse. The technique is based on the acquisition and subtraction of two datasets, one obtained with and one without T2prep. The subtraction step allows nulling the signal of arterial blood while maintaining signal of muscle and vessel wall. In order to minimize the motion sensitivity we developed an interleaved acquisition for the T2prep and non-T2prep images, which allows obtaining coronary vessel wall images from a whole heart acquisition with minimal misregistration artefacts.

16:48 0319.   
3D Variable-Flip-Angle TSE with Prospective Self-Gating of Swallowing Motion: Initial Experience in Carotid Artery Wall MRI
Zhaoyang Fan1, Petter Dyverfeldt2, Xin Liu3, Sven Zuehlsdorff4, Vibhas Deshpande5, David Saloner2, and Debiao Li1
1Cedars-Sinai Medical Center and University of California, Los Angeles, CA, United States, 2Departments of Radiology and Biomedical Imaging, University of California, San Francisco, CA, United States, 3Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China, 4Siemens Cardiovascular R&D, Chicago, IL, United States, 5Siemens Healthcare, San Francisco, CA, United States

3D black-blood MRI is a promising technique for carotid artery wall assessment but is inherently susceptible to motion, such as swallowing. A self-gating (SG) method in combination with a 3D variable-flip-angle TSE sequence, SPACE, has been proposed for prospectively gating swallowing motion. This work aimed to test the utility of the SG-SPACE technique on healthy volunteers and patients. Results showed that the SG approach significantly mitigates the swallowing-induced artifacts, including blurred wall boundary and reduced wall-to-background contrast. Significant improvement in image quality and vessel wall delineation was obtained, indicating its potential to enhance the performance of 3D vessel wall MRI.

17:00 0320.   
3D Isotropic High Resolution T1 Insensitive Flow Suppression using Time Efficient Phase Sensitive Double Inversion Recovery permission withheld
Zechen Zhou1, Rui Li1, and Chun Yuan1,2
1Center for Biomedical Imaging Research, Tsinghua University, Beijing, China, 2Department of Radiology, University of Washington, Seattle, WA, United States

Currently, Quadruple Inversion Recovery (QIR) prepared TSE sequence is a common black blood method to image the pre- and post- contrast enhanced vessel wall which can detect the neovasculature and inflammation in atherosclerotic plaque. However, this QIR prepared TSE technique is limited by the acquisition efficiency and partial volume effect. In this work, we first explained the principle of Phase Sensitive Double Inversion Recovery (PSDIR) and then investigated a time efficient 3D isotropic high resolution PSDIR based T1 insensitive flow suppression vessel wall imaging technique. This technique can further improve the CNR between lumen and vessel wall and be potentially applied for dynamic contrast enhanced black and white blood vessel wall imaging.

17:12 0321.   Dual Imaging with Bright Blood Arterial Input Function and Black Blood Tissue Acquisition for Vessel Wall Imaging in Atherosclerosis: BB-SHILO (Black-Blood Simultaneous High-Low Temporal (Low-High Spatial) Resolution Imaging)
Philip M Robson1, Claudia Calcagno1, Sarayu Ramachandran1, Venkatesh Mani1, Melanie Kotys-Traughber2, and Zahi A Fayad1
1Translational and Molecular Imaging Institute, Mount Sinai School of Medicine, New York, NY, United States, 2Philips Healthcare, Cleveland, OH, United States

A new sequence interleaving bright-blood GRE full-image and dark-blood SE image-segment acquisitions is investigated for application to quantitative Dynamic Contrast Enhanced imaging of the carotid arteries in atherosclerosis. Bright-blood images are acquired with 1-sec temporal and low 0.5x4-mm spatial resolutions to capture the arterial input function, while the interleaved dark-blood images have lower temporal and 0.5x0.5-mm spatial resolution to image the thin vessel wall without blooming of the bright vessel lumen. This study in three subjects demonstrates the feasibility of simultaneously-acquired combined image contrasts. Contrast agent kinetic parameters measured in the vessel wall are consistent with those in the literature.

17:24 0322.   Fast Three-Dimensional Black-Blood MRI Based on Compressed Sensing
Bo Li1, Bin Chen2, Shuangxi Ji1, Li Dong3, Zhaoqi Zhang3, Wenchao Cai4, Xiaoying Wang4, Jue Zhang1,2, and Jing Fang1,2
1College of Engineering, Peking University, Beijing, China, 2Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China, 3Dept. of Radiology, An Zhen Hospital, Beijing, China, 4Dept. of Radiology, Peking University First Hospital, Beijing, China

High-resolution 3D-MERGE technique based black-blood imaging has been reported to quantitatively measure carotid atherosclerotic plaque morphology and tissue composition. However, it brings about relative long time consuming due to the use of motion-sensitized preparation. Nevertheless, compressed sensing (CS) can improve temporal resolution by reconstructing images from a dramatically small number of data without introducing severe image artifacts. Therefore we investigate the feasibility of the fast 3D-MERGE imaging using CS reconstruction. Moreover, compared to the fully k-space sampling approach, we verified whether or not the CS based 3D MERGE images could provide appropriate blood signal suppression and comparable details.

17:36 0323.   
Steady-State Motion-Induced Contrast Using DANTE Pulse Trains: A Novel Approach to Black Blood Imaging
Linqing Li1, Karla Miller1, Jamie Near1, and Peter Jezzard1
1FMRIB, Clinical Neurology Department, University of Oxford, Oxford, United Kingdom

During application of DANTE (a rapid series of low flip angle RF pulses interspersed with gradients)pulse trains, longitudinal magnetization of flowing spins is largely (or fully) attenuated. This is in contrast to static tissue, whose longitudinal magnetization is mostly preserved. DANTE may be well suited for mutilslice imaging acquisition. This work is to introduce this novel approach to fast black blood imaging. It was found that the overall improvement of the DANTE method over the existing methods is approximately factor of 2.

17:48 0324.   
Simultaneous PET/MR of Atherosclerotic Plaques in Peripheral Artery Disease: Preliminary Results
Isabel Dregely1, Stephan G Nekolla1, Carl Ganter2, Tobias Koppara3, Hua-Lei Zhang1, Sylvia Schachoff1, Anna Winter1, Marijana Dzijan-Horn3, Markus Schwaiger1, and Tareq Ibrahim3
1Department of Nuclear Medicine, Klinikum rechts der Isar der TU München, Munich, Bavaria, Germany, 2Department of Radiology, Klinikum rechts der Isar der TU München, Munich, Bavaria, Germany, 3Department of Cardiology and Angiology, Klinikum rechts der Isar der TU München, Munich, Bavaria, Germany

Non-invasive imaging techniques have the potential to identify high risk patients in atherosclerotic disease. In this study we demonstrate the feasibility of simultaneous PET/MR in peripheral artery disease (PAD) to improve characterization of atherosclerotic plaques.