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

MRA: Still Worth Mining
Wednesday 24 April 2013
Room 255 EF  16:00 - 18:00 Moderators: J. Paul Finn, Stefan O. Sch÷nberg

16:00 0539.   
Time-Resolved Non-Contrast Enhanced 4-D Dynamic MRA Using Multi-Bolus TrueFISP Based Spin Tagging with Alternating Radiofrequency (True-STAR)
Lirong Yan1, Noriko Salamon2, and Danny J.J. Wang1
1Neurology, UCLA, Los Angeles, CA, United States, 2Radiology, UCLA, Los Angeles, CA, United States

The purpose of this study is to introduce a new non-contrast dynamic MRA (dMRA) technique termed multi-bolus TrueSTAR, by combining the benefits of pulsed ASL, including short RF duration and low SAR, and pseudo-continuous ASL (pCASL), including higher SNR and prolonged labeling bolus. Multi-bolus dMRA offered a prolonged tagging bolus compared to the standard single-bolus dMRA, and allowed improved visualization of the draining veins in arteriovenous malformation. Compared to pCASL based dMRA, multi-bolus dMRA provided visualization of the full passage of the labeled blood with the flexibility for both static and dynamic MRA.

16:12 0540.   Non-Contrast Enhanced Time-Resolved MR Angiography with Time-Of-Arrival Mapping: A Feasibility Trial in Cerebral AVM
Masanobu Nakamura1, Masami Yoneyama1, Takashi Tabuchi1, Atsushi Takemura2, Makoto Obara2, and Taro Takahara3
1Yaesu clinic, Tokyo, Japan, 2Philips Electronics Japan, Tokyo, Japan, 3Tokai University School of Engineering, Kanagawa, Japan

A new technique was presented for non-contrast volumetric time-resolved MRA (Contrast inherent INflow Enhanced Multi phase Angiography using pseudo-continuous arterial spin labeling; CINEMA-PCASL) [4]. This technique requires no catheter insertion or contrast agent and provides useful qualitative information on the morphologic and dynamic filling of intracranial vessels. The feasibility study of CINEMA-PCASL sequence has been reported recently on healthy volunteers, but its clinical application in patients with AVMs has not been conducted. The purpose of this study was to evaluate the diagnostic use of non-contrast time-resolved MRA with time-of-arrival map in patients with cerebral AVM.

16:24 0541.   Comparison of Noncontrast FSD MRA to Time Resolved (TWIST) and High Resolution Contrast Enhanced MRA of the Hands in Patients with Systemic Lupus Erythematosus (SLE) and Clinical Vasculopathy.
Rola Saouaf1, Zhaoyang Fan2, Mariko L. Ishimori3, Lindsy J. Forbess3, Emmanuil Smorodinsky1, Daniel J. Wallace3, Michael H. Weisman3, and Debiao Li2
1Imaging, Cedars-Sinai Medical Center, Los Angeles, California, United States, 2Biomedical Imaging Research Institute, Cedars-Sinai Medical Center, Los Angeles, California, United States,3Rheumatology, Cedars-Sinai Medical Center, Los Angeles, California, United States

Systemic Lupus Erythematosus (SLE) is an autoimmune disease which can affect hand vasculature. Noncontrast FSD MRA was compared to contrast enhanced (CE) Time resolve (TWIST) and high resolution MRA. Vascular pathology was compared to clinical findings. Preliminary data shows FSD MRA was superior to CE MRA in all segments evaluated. Vascular pathology had variable concordance with clinical presentation which will warrant further investigation.

16:36 0542.   
High Spatial and Temporal Resolution Dynamic Contrast-Enhanced Magnetic Resonance Angiography (CE-MRA) Using Compressed Sensing with Magnitude Image Subtraction
Stanislas Rapacchi1, Fei Han1, Yutaka Natsuaki2, Randall Kroeker3, Adam Plotnik1, Evan Lehrman1, James Sayre1, Gerhard Laub4, J. Paul Finn5, and Peng Hu5
1Departement of Radiology, UCLA, Los Angeles, CA, United States, 2Cardiovascular, Siemens Healthcare, Los Angeles, CA, United States, 3Siemens Healthcare, Winnipeg, MB, Canada, 4Siemens Healthcare, Los Angeles, CA, United States, 5Departement of Radiology, University of California Los Angeles, Los Angeles, CA, United States

We propose a compressed sensing technique based on magnitude image subtraction for high spatial and temporal resolution dynamic contrast-enhanced MR angiography (CE-MRA). In a breath-held CE-MRA acquisition, the subtraction of a pre-contrast mask to a post-contrast image promotes sparsity of the difference image. This "subtraction-sparsity" has been previously reported and our proposed magnitude subtraction-based technique takes advantage of this sparsity while avoiding a number of issues with direct k-space subtraction. Full-sampled Cartesian 3D CE-MRA datasets were retrospectively under-sampled and different strategies of reconstruction were evaluated. Our technique was tested with a prospectively under-sampled CE-MRA sequence achieving an acceleration of 12.5x.

16:48 0543.   
Off-Resonance-Robust Velocity-Selective Magnetization Preparation for Non-Contrast-Enhanced Peripheral MRA
Taehoon Shin1, Bob S. Hu1,2, and Dwight G. Nishimura1
1Electrical Engineering, Stanford University, Stanford, CA, United States, 2Palo Alto Foundation, Palo Alto, CA, United States

Velocity-selective (VS) excitation is a promising magnetization preparation for non-contrast-enhanced (NCE) MRA as it can generate positive angiographic contrast directly without subtraction. This work aims to develop a new version of the VS excitation pulse sequence that is robust to off-resonance and demonstrate its application to NCE peripheral MRA. The proposed VS pulse design modifies a reference k-space-based design by incorporating 180┬░ refocusing pulses and tailoring sequence parameters in a limited velocity region-of-interest. The improved off-resonance immunity and clinical feasibility of NCE peripheral MRA using the proposed VS preparation are shown in healthy and patient subjects.

17:00 0544.   Time-Resolved Nonenhanced QISS MR Angiography Using a Golden Angle Radial Trajectory and HYPR
Ioannis Koktzoglou1,2, Charles A. Mistretta3, Shivraman Giri4, Parag Amin5, and Robert R. Edelman1,6
1Radiology, NorthShore University HealthSystem, Evanston, Illinois, United States, 2The University of Chicago Pritzker School of Medicine, Chicago, IL, United States, 3Radiology, University of Wisconsin-Madison, Madison, WI, United States, 4Siemens Healthcare, Chicago, IL, United States, 5Radiology, Northwestern University, Chicago, IL, United States, 6Northwestern University Feinberg School of Medicine, Chicago, IL, United States

A time-resolved variation of nonenhanced quiescent interval single-shot (QISS) MRA using a golden angle radial trajectory and highly constrained back projection (HYPR) reconstruction is presented. The method permits rapid display of peripheral arterial anatomy and flow with high spatial and temporal resolution.

17:12 0545.   
CMRA with 100% Navigator Efficiency with Radial 2D Self Navigation
Jonathan Powell1, Markus Henningsson1, Claudia Prieto1, and Rene M. Botnar1
1Division of Imaging Sciences and Biomedical Engineering, Kings College London, London, London, United Kingdom

We achieve 100% navigator efficiency for free breathing 3D coronary magnetic resonance angiography, using radial self navigation to retrospectively correct for motion artefacts. Compared to 1D navigator gated scans we achieve equivalent image quality with substantially reduced scan time.

17:24 0546.   Highly Efficient Respiratory Motion Compensated Free-Breathing Coronary MRA Using Golden-Step Cartesian Acquisition
Claudia Prieto1,2, Mariya Doneva3, Muhammad Usman1, Rene M. Botnar1, and Tobias Schaeffter1
1Division of Imaging Sciences and Biomedical Engineering, King's College London, London, United Kingdom, 2Escuela de Ingenieria, Pontificia Universidad Catolica de Chile, Santiago, Chile, 3Philips Research Europe, Hamburg, Germany

A 3D respiratory motion-corrected reconstruction approach for whole-heart coronary MRA is proposed. This approach achieves 100% scan efficiency by correcting all acquired data directly in the reconstruction after image-based registration of high-resolution undersampled reconstructed data. This is achieved by using a golden-step spiral-like Cartesian acquisition. This phase-encoding scheme ensures a quasi-uniform sampling for any respiratory window and at any breathing position. Motion parameters are estimated from undersampled respiratory-resolved images reconstructed with iterative SENSE and 3D motion correction is performed directly in the reconstruction using a multiple-coils generalized matrix formulation approach. The proposed approach achieves high image quality comparable to that of an 8mm navigator-gated acquisition, which is less efficient.

17:36 0547.   An Initial Report on the Performance of Post Contrast Self-Navigated Whole-Heart Coronary MRI in Patients with Suspected or Established Coronary Artery Disease
Davide Piccini1,2, Christophe Sierro3, Juerg Schwitter3, Pierre Monney3, Gabriella Vincenti3, Simon C. Koestner3, Didier Locca3, Tobias Rutz3, Arne Littmann4, Michael O. Zenge4, Gunnar Krueger1,5, and Matthias Stuber2
1Advanced Clinical Imaging Technology, Siemens Healthcare IM S AW, Lausanne, Switzerland, 2Department of Radiology, University Hospital (CHUV) and University of Lausanne (UNIL) / Center for Biomedical Imaging (CIBM), Lausanne, Switzerland, 3Division of Cardiology and Cardiac MR Center, University Hospital of Lausanne (CHUV), Lausanne, Switzerland, 4MR Application and Workflow Development, Healthcare Sector, Siemens AG, Erlangen, Germany, 5CIBM-AIT, Ecole Polytechnique Federale de Lausanne, Lausanne, Switzerland

While self-navigated (SN) whole heart coronary MRA data have successfully been acquired in healthy adult subjects, the performance of this technique remains to be ascertained in patients with suspected or established coronary artery disease (CAD). In this work our 3D radial SN whole-heart technique was optionally integrated in clinical examinations of 60 patients with suspected or confirmed CAD. All coronary segments were graded by experts and compared with x-ray angiography, when available, for detection of stenoses. The SN technique was also tested for identification of congenital anomalies of the coronary arteries.

17:48 0548.   Assessment of Coronary Artery Disease Using 3.0T Magnetic Resonance Coronary Angiography: A National Multicenter Trial -permission withheld
Kuncheng Li1, Qi Yang2, Bin Sun3, Hong Yun4, Lijun Tang5, Junling Xu6, Shurong Li7, Mengqi Wei8, Zhenbin Cao9, Lixin Jin10, Mengsu Zeng4, Qing Duan3, Yi Huan8, Quanfei Meng7, Xiangquan Kong9, and Dehang Wang5
1Radiology Department, Xuanwu Hospital, Beijing, China, 2Xuanwu Hospital, Beijing, China, 3Fujian Union Hospital, Fuzhou, China, 4Zhongshan hospital, Fudan University, Shanghai, China, 5Jiangsu Province Hospital, Nanjing Medical University, Nanjing, China, 6Henan Provincial Hospital, Zhengzhou, China, 7First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China, 8Xijing Hospital, Fourth Military Medical University, Xian, China, 9Wuhan Union Hospital, Huazhong University of Science, Wuhan, China, 10Siemens Healthcare, MR Collaboration NE Asia, Shanghai, China

Among patients who were scheduled to conventional x-ray coronary angiography, coronary MRA at 3.0T demonstrates high accuracy for detection of significant coronary artery stenosis. With contemporary techniques, 3.0T whole heart coronary MRA can be performed efficiently, and warrants greater consideration as a suitable noninvasive method to exclude obstructive coronary artery disease.