Electronic poster


Thursday 13:30-15:30 Computer 34



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Thursday 13:30-15:30 Computer 34

13:30 3660. Monitoring Iron Chelation Effect in Hearts of Thalassaemia Patients with Improved Sensitivity Using Reduced Transverse Relaxation Rate (RR2)

Jerry S. Cheung1,2, Wing-Yan Au3, Shau-Yin Ha4, Jens H. Jensen5, Dan Kim5, Abby Y. Ding1,2, Iris Y. Zhou1,2, Hua Guo5, Truman R. Brown6, Winnie C.W. Chu7, Darshana D. Rasalkar7, Pek-Lan Khong8, Gary M. Brittenham9, Ed X. Wu1,2

1Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China; 2Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China; 3Department of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China; 4Department of Pediatrics and Adolescent Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China; 5Department of Radiology, New York University School of Medicine, New York, United States; 6Department of Radiology, Columbia University, New York, United States; 7Department of Diagnostic Radiology and Organ Imaging, The Chinese University of Hong Kong, Hong Kong SAR, China; 8Department of Diagnostic Radiology, The University of Hong Kong, Pokfulam, Hong Kong SAR, China; 9Department of Pediatrics, Columbia University, New York, United States

Accurate MRI characterization of myocardial iron is needed to improve the diagnosis and management of thalassaemia patients with transfusional iron overload. This study aimed to demonstrate that a new transverse relaxation index, the reduced R2 (RR2) that is estimated from non-monoexponential multi-echo CPMG signal decay and sensitive to ferritin iron, could detect the myocardial iron changes immediately following 1-week iron chelation suspension in thalassaemia patients at 3T.



14:00 3661. Quantitative T1 and T2 Measurements of Tissue Characteristics in Myocardial Infarction – Pilot Results at 3T

Stefan K. Piechnik1, Erica Dall'Armellina1, Vanessa M. Ferreira1, Lowri E. Cochlin2, Jürgen E. Schneider1, Stefan Neubauer1, Matthew D. Robson1

1Cardiovascular Medicine, OCMR, Oxford University , Oxford, Oxfordshire, United Kingdom; 2Dept of Physiology, Anatomy and Genetics, Oxford University, Oxford, Oxfordshire, United Kingdom

We present preliminary results of T1- and T2-mapping at 3T in sub-acute myocardial infarction to demonstrate the ability of quantitative CMR in delineating myocardial tissue changes following an ischemic event.



14:30 3662. Free-Breathing, Single Shot Fat-Water Separated Cardiac Imaging with Motion Corrected Averaging

Peter Kellman1, Diego Hernando2, Saurabh Shah3, Christophe Chefd'hotel4, Z-P Liang2, Andrew E. Arai1

1National Institutes of Health, Bethesda, MD, United States; 2University of Illinois, Urbana, IL, United States; 3Siemens Medical Solutions, Chicago, IL, United States; 4Siemens Corporate Research, Princeton, NJ, United States

A rapid fat/water separated imaging protocol has been developed for free-breathing cardiac applications for cases where patients have difficulty breath-holding or have significant arrhythmias. The method combines a 2 echo GRE acquisition and parallel imaging, and may be used with repeated measurements and motion corrected averaging to further improve image quality. The method has been applied to both pre-contrast and late enhancement imaging.



15:00 3663. Navigator Guided High-Resolution Single-Shot Black-Blood TSE Images Using ZOOM and Sensitivity Encoding (SENSE) on a 32 Channel RF System

Raja Muthupillai1, Amol Pednekar2, Claudio Arena1, Scott D. Flamm1, Benjamin Y. Cheong1

1Diagnostic and Interventional Radiology, St. Luke's Episcopal Hospital, Houston, TX, United States; 2Philips Healthcare

We demonstrate that by using a judicious combination of reduced FOV imaging (ZOOM), Sensitivity Encoding (SENSE), and half-scan, it is feasible to obtain diagnostic quality single-shot (SSH) dual-inversion recovery prepared black blood(BB) turbo spin echo(TSE) images with minimal image blurring during normal respiration. The results of the study, performed on 8 asymptomatic subjects, show that SSH T2-TSE images acquired using ZOOM+SENSE under navigator triggering, yield images with quality that is comparable to conventional multi-shot BB-TSE images acquired over a 14-16 heart beat breathhold.



Coronary Artery & Vessel Wall Imaging

Hall B Monday 14:00-16:00 Computer 35

14:00 3664. Retrospective Estimation of 3D Respiratory Motion Vectors in Coronary MRI

Alan Christopher O'Connor1, Mehdi Hedjazi Moghari1, Peng Hu1, Dana C. Peters1, Warren J. Manning1, Reza Nezafat1, Roger Ware Brockett2

1Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States; 2SEAS, Harvard University, Cambridge, MA, United States

Navigator correction methods were developed to increase the gating window size possible for free-breathing cardiac MRI and consequently reduce scan time. These methods typically rely on a generic scale-factor between measured diaphragm motion and heart motion. We present a novel scheme for estimating patient-, direction-, and coil-specific motion vectors directly from the scan data to correct for phase errors caused by respiratory motion of the heart.



14:30 3665. Quantitative Assessment of Right Coronary Artery MRI Using Quadrature RF Coils at 7 Tesla, Incorporating a Direct Comparison of Results to Those Acquired at 3 Tesla.

Saskia van Elderen1, Maarten Versluis1, Jos Westenberg1, Harsh Agarwal2, Nadine Smith1, Matthias Stuber3, Albert de Roos1, Andrew Webb1

1Radiology, Leiden University Medical Center, Leiden, Netherlands; 2Johns Hopkins University; 3Department of Radiology, Centre Hospitalier Universitaire Vaudois and University of Lausanne, Lausanne, Switzerland

Using a quadrature RF coil with dimensions optimized for reliable navigator gating, this study with ten volunteers shows that 7T right coronary angiograms can be acquired with improved vessel sharpness compared to those obtained at 3T using identical imaging parameters.



15:00 3666. The Influence of Sublingual Nitroglycerin on Contrast -Enhanced Whole-Heart Coronary Magnetic Resonance Angiography at 3.0-T

Bin Sun1, ZhiYong Chen2, LiXin Jin3, Qing Duan

1Radiology, FuJian Medical University Union Hospital, FuZhou, FuJian, China; 2Radiology, FuJian Medical University Union Hospital, China; 3Siemens Healthcare, MR Collaboration NE Asia, China

This article describes the influence of sublingual nitroglycerin spray on the lumen diameter, number of side branches visualized, average vessel length of 3.0-T contrast-enhanced whole-heart coronary magnetic resonance angiography. Twenty-four patients were prospectively included in this study: 12 were examined without sublingual nitroglycerin, and 12 were examined after the administration of sublingual nitroglycerin. Two blinded observers quantitatively assessed lumen diameter and length in the RCA, LAD and LCX. The number of acute marginal branches and septal branches was counted. The number of clinical side effects was evaluated. Sublingual nitroglycerin spray significantly dilates the coronary arteries and allows more side branches to be visualized at 3.0-T contrast-enhanced whole-heart CMRA without increasing resolution or increasing the number of side effects.



15:30 3667. 3T Coronary MRA Using 3D Multi-Interleaved Multi-Echo Acquisition and VARPRO Fat-Water Separation

Saurabh Shah1, Xiaoming Bi1, Diego Hernando2, Peter Weale1, Sven Zuehlsdorff1, Sonia Nielles-Vallespin3, Peter Kellman4

1Siemens Healthcare, Chicago, IL, United States; 2University of Illinois at Urbana-Champaign, Urbana, IL, United States; 3Royal Brompton And Harefield NHS Foundation Trust, London, United Kingdom; 4National Institutes of Health / NHLBI, Bethesda, MD, United States

A 3D free-breathing navigator-gated multi-interleaved multi-echo GRE sequence is implemented with VARPRO fat-water separation and utilized in targeted acquisition of coronary arteries at 3T. This approach achieves reliable fat-suppression across field-of-view and provides clear depiction of coronaries for enhanced visualization.



Tuesday 13:30-15:30 Computer 35

13:30 3668. Prospective Respiratory Navigator Gated RF Excitation in Whole-Heart Coronary MRA at 3T

Jing Yu1,2, Michael Schär, 23, Harsh Agarwal, 2,4, Matthias Stuber2,5

1Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States; 2Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, MD, United States; 3Philips Healthcare, Cleveland, OH, United States; 4Department of Electrical and Computer Engineering, John Hopkins University, Baltimore, MD, United States; 5Department of Radiology, University Hospital Center and University of Lausanne (CHUV), Lausanne, VD, Switzerland

One of the challenges in coronary MRA is insufficient SNR. To improve the blood-pool SNR in prospective respiratory navigator gated whole-heart coronary MRA, radiofrequency excitations of the gradient echo readout train are suspended in real-time, when the respiratory position is outside the predefined gating window. Phase encoding is adapted to deposit the increased signal in central k-space and to minimize signal variation of adjacent k-space profiles. Consistent with the numerical simulation, in vivo experiments demonstrated 35% improvement in blood-pool SNR, without compromising scan time or spatial resolution. The SNR advantage affords great potential towards better depiction of the coronary arteries.



14:00 3669. Coronary Sinus Flow Quantification at 3T and Cold Pressor Test for Non Invasive Evaluation of Coronary Endothelial Function

Pierre-Julien Moro1,2, Alexis Jacquier1, Frank Kober1, Jean-Louis Bonnet2, Patrick Cozzone1, Monique Bernard3

1Centre de Résonance Magnétique Biologique et Médicale, CNRS UMR 6612, Université de la Méditerranée, Faculté de Médecine, Marseille, France; 2Cardiology, CHU Timone, Marseille, France; 3Centre de Résonance Magnétique Biologique et Médicale, CNRS UMR 6612, Université de la Méditerranée , Faculté de Médecine, Marseille, France

The purpose of this study was to assess a non invasive measure of coronary endothelial function. Coronary sinus flow was measured in 14 volunteers at rest and during cold pressor test (CPT) using non breath-hold velocity encoded phase contrast cine MRI. Myocardial blood flow (MBF) significantly increased by 55 ± 38 % during CPT compared to the rest examination (p<0.0001); coronary blood flow was 0.66 ± 0.22 ml/min/g at baseline and 1.03 ± 0.41 ml/min/g after CPT. This non invasive measure may help to detect changes in endothelial function which occur early in a variety of cardiovascular diseases.



14:30 3670. Prospective Projection-Based Respiratory Whole-Heart Coronary MRI with Patient-Specific Tracking Factor

Mehdi Hedjazi Moghari1, Peng Hu1, Christian Stoeck2, Jouke Smink3, Dana C. Peters1, Beth Goddu1, Lois Goepfert1, Warren J. Manning1, Reza Nezafat1

1Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States; 2University and ETH, Biomedical Engineering, Zurich, Switzerland; 3Philips-Healthcare, Best, Netherland

The impact of correct subject-dependent slice tracking factor in whole-heart coronary imaging is studied in this paper. In preparation phase, two projection-based respiratory navigators are positioned at the diaphragm edge and center of heart to calculate the slice tracking factor. The projection-based navigator at the diaphragm with the estimated scale factor is employed for the whole-heart coronary image reconstruction. The constructed images outperform the ones acquired with the pencil beam navigator with the constant scale factor 0.6.



15:00 3671. Feasibility Study of Motion Pre-Analysis Method for Whole-Heart Magnetic Resonance Coronary Angiography (Wh Mrca) at Different Breathing Levels

Shigehide Kuhara1, Tomohisa Okada2, Ayako Ninomiya1, Toshikazu Kamae2, Shotaro Kanao2, Tetsuo Sato3, Kotaro Minato3, Kaori Togashi2

1MRI Systems Division, Toshiba Medical Systems, Otawara-Shi, Tochigi, Japan; 2Department of Diagnostic Radiology, Kyoto University Hospital, Kyoto, Japan; 3Nara Institute of Science and Technology, Nara, Japan

We have developed the Motion Pre-Analysis Method to determine the appropriate RMC coefficient before WH MRCA (Whole Heart Magnetic Resonance Coronary Angiography) examinations and investigated coefficients between motions of the diaphragm and the heart at different breathing levels by using an inflatable blood pressure cuff placed under an abdominal band. The results of this study suggest that the RMC coefficient may change for each person and abdominal pressures applied. The image quality was slightly improved by using the pre-analyzed RMC coefficient. It is therefore expected that this Motion Pre-Analysis Method would improve visualization of WH MRCA examinations.



Wednesday 13:30-15:30 Computer 35

13:30 3672. Local Inversion Spiral Coronary Vessel Wall Imaging: A Comparison Between 1.5T and 3T

Sarah Anne Peel1, Tarique Hussain1, Gerald Greil1, Tobias Schaeffter1, René M. Botnar1

1Division of Imaging Sciences, King's College London, London, United Kingdom

In this study we sought to compare the 3D spiral coronary vessel wall imaging using the local inversion pre-pulse technique on 1.5T and 3T systems. Imaging at 1.5T resulted in consistent image quality and good blood suppression. While SNR was improved at 3T, image quality was more consistent and artifact level lower at 1.5T. Although excellent coronary vessel wall images can be acquired at 3T, improvements in shimming and f0 determination are required to improve overall robustness compared to 1.5T.



14:00 3673. The Use of Biofeedback with MCLAWS to Guide Respiration and Provide Inspiratory and Expiratory Images from a Single Navigator-Gated 3D Coronary MRA Acquisition.

Permi Jhooti1, Jennifer Keegan2, Klaus Scheffler1, David Firmin2

1Radiological Physics, University of Basel, Basel, Switzerland; 2CMR Unit, Royal Brompton Hospital, United Kingdom

The mCLAWS technique produces whole heart images in the fastest possible time for a given respiratory pattern and gating window, as well as image datasets at end expiration and end inspiration. The end inspiratory images are generally poorer quality than the end expiratory images because the end inspiratory position is usually more variable and the end inspiratory pause shorter. We have implemented a respiratory biofeedback ‘game’ with a multi-navigator mCLAWS technique to regularise the subjects’ breathing patterns and to enable the acquisition of high quality end inspiratory and end expiratory images from a single whole heart acquisition.



14:30 3674. High Resolution 3D Spiral Coronary Vessel Wall Imaging with >99% Respiratory Efficiency Using Beat to Beat Respiratory Motion Correction: Quantitative Comparison with Navigator Gated 2D Spiral and Turbo Spin Echo Imaging

Andrew David Scott1,2, Jennifer Keegan, 1,2, David N. Firmin, 1,2

1National Heart and Lung Institute, Imperial College, London, Greater London, United Kingdom; 2Cardiovascular Magnetic Resonance Unit, The Royal Brompton Hospital, London, Greater London, United Kingdom

High resolution 3D coronary artery wall imaging potentially enables the assessment of the full 3D extent of a plaque, but is time consuming when used with navigator gating. We compare 3D spiral right coronary artery wall imaging with a highly efficient beat-to-beat respiratory-motion-correction technique using localized tracking of the fat around the artery (99.6% respiratory efficiency) with navigator gated (39% efficient) 2D spiral and 2D turbo spin echo techniques. The techniques were compared quantitatively using vessel wall thickness. The improved respiratory efficiency of the beat-to-beat respiratory-motion-correction technique facilitates high resolution 3D coronary wall imaging within a reasonable duration.



15:00 3675. MR Imaging of Myocardial Scar and Coronary Vein Anatomy in Patients Awaiting Cardiac Resynchronization Therapy Using a High-Relaxivity Contrast Agent.

Simon Graham Duckett1, Matthew Ginks1, Benjamin R. Knowles1, Amedeo Chiribiri1, Stephen Sinclair1, Gerry Carr-White2, Aldo Rinaldi2, Rene Botnar1, Eike Nagel1, Reza Razavi1, Tobias Schaeffter1

1Kings College London, London, United Kingdom; 2Guy's and St Thomas's Hospital

As Cardiac resynchronization therapy is becoming more widely available for the treatment of patients with heart failure, there has been increased interest in imaging the coronary sinus and its tributaries. Previous studies using CMR have mainly focused on using intravascular contrast agents (CA), which give no useful information about myocardial scar, and require a separate MR-exam to assess scar and viability. Most of these studies patients with normal left ventricular function have been recruited. We present a single CMR examination imaging the coronary venous anatomy and myocardial scar in patients with HF using a high-relaxivity contrast agent.



Thursday 13:30-15:30 Computer 35

13:30 3676. Non-Invasive Quantification of Atherosclerotic Plaque Inflammation and Neovascularity in a Rabbit Model Using Bright-Blood Dynamic Contrast-Enhanced MRI

John A. Ronald1, Yuanxin Chen2, Kem A. Rogers2, William S. Kerwin3, Brian K. Rutt1

1Radiology, Stanford University, Stanford, CA, United States; 2Anatomy and Cell Biology, University of Western Ontario, London, Ontario, Canada; 3Radiology, University of Washington, Seattle, WA, United States

Atherosclerotic plaques enriched in inflammatory cells and neovessels are prone to rupture, the life-threatening event underlying heart attacks and stroke. Here we performed the first successful bright-blood dynamic contrast enhanced MR imaging of rabbit atherosclerotic plaques that resemble mid-stage plaques in humans and show that the transfer constant, Ktrans, correlates well with histopathological measures of both macrophage (r=0.4438, p=0.011) and neovessel density (r=0.4186, p=0.027). This is an important extension of this technique, which through necessity has been proven useful for advanced human disease only, and holds promise for its use in assessing the effects of anti-angiogenic/anti-inflammatory therapies in earlier plaques.



14:00 3677. Whole Heart T1 Weighted Coronary Plaque MR Imaging at 3T Using 32channel Cardiac Coils

Hideki Miyagi1, Hajime Sakuma1, Shingo Kato1, Kakuya Kitagawa1, Motonori Nagata1, Takase Shinichi1, Sigfridsson Andreas1, Masatoshi Miyahara2, Mashio Nakamura2, Yoshihide Mitani3, Hiroyuki Ohashi3

1Department of Radiology, Mie University Hospital, Tsu, Mie, Japan; 2Department of Cardiology, Mie University Hospital, Tsu, Mie, Japan; 3Department of Pediatrics, Mie University Hospital, Tsu, Mie, Japan

Whole heart 3D T1-weighted TSE images were acquired with 3T MR imager and 32-channel cardiac coils in 10 patients with Kawasaki disease who had coronary artery aneurysms and 5 patients with coronary artery disease (CAD). Hyperintense coronary plaque (HIP) was observed in 5 of 10 patients with Kawasaki disease and 4 of 5 CAD patients. On MDCT and IVUS, HIP corresponded to thrombus along the vessel wall or positive remodeling plaque with ultrasound attenuation. 3T T1-weighted coronary plaque MRI allows for noninvasive screening of HIP in the entire coronary artery tree with an averaged imaging time of < 10 minutes.



14:30 3678. Evaluating Anti-Inflammatory Efficacy of Pioglitazone in a Rabbit Model of Atherosclerosis with Multimodality Imaging

Stephen D. Dickson1, Esad Vucic1,2, Claudia Calcagno1, James HF Rudd1, James Lin1, Jessica Mounessa1, Michelle Roytman1, Zahi A. Fayad1,2

1Radiology, Mount Sinai School of Medicine, New York, NY, United States; 2Medicine, Mount Sinai School of Medicine, New York, NY, United States

Dynamic contrast enhanced (DCE) MRI and F18-fluorodeoxyglucose (FDG) PET/CT was performed on control and pioglitazone-treated atherosclerotic New Zealand White Rabbits at three time points over three months. After three months, treated animals showed decreased MRI contrast agent uptake in plaque as well as decreased FDG signal as compared to controls. Macrophage specific immuno-histochemistry validated anti-inflammatory observations.



15:00 3679. Toward a Novel Implantable Contrast Agent for Enhanced MRI Definition of the Vein Graft Wall: Long-Term Stability Assessment of Gd-DTPA Immobilized Contrast-Enhanced (ICE) MRI

Dimitris Mitsouras1,2, Praveen K. Vemula, 23, Peng Yu, 2,4, Ming Tao, 2,4, Binh T. Nguyen, 2,4, Jeffrey Karp, 23, Keith C. Ozaki, 2,4, Robert V. Mulkern, 2,5, Frank J. Rybicki1,2

1Dept of Radiology, Brigham and Women's Hospital, Boston, MA, United States; 2Harvard University, Cambridge, MA, United States; 3Dept of Medicine, Brigham and Women's Hospital, Boston, MA, United States; 4Dept of Surgery, Brigham and Women's Hospital, Boston, MA, United States; 5Dept of Radiology, Children's Hospital, Boston, MA, United States

Nearly half of 500,000 vein grafts implanted annually in the US fail. Although MR has enormous potential to assess remodeling and track disease progression, it is severely limited by excessive scan times required to resolve the graft wall (<1mm thickness). Our long-term goal is the development of an implantable MR contrast agent, immobilized on the vein graft surface ex vivo at the time of operation, used to enhance both the MR signal and tissue contrast available for subsequent imaging. We demonstrate for the first time such long-term signal enhancement using a modified Gd-DTPA complex successfully immobilized on the vein surface.



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