TRADITIONAL POSTER - ismrm

Poster Sessions
1437. Realtime Cine MRI in Mice with a Single-Shot EPI Sequence and the Karhunen–Loeve Transform
Guangping Dai 1 , Yu Ding 2 , Shuning Huang 1 , Orlando P. Simonetti 2 , David E. Sosnovik 3
1 Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School; 2 Dorothy M. Davis Heart and
Lung Research Institute, The Ohio State University; 3 Martinos Center for Biomedical Imaging, Massachusetts General Hospital,
Harvard Medical School, Boston, MA, United States
Realtime cine MRI of the mouse heart is reported using a single-shot EPI sequence and the Karhunen–Loeve transform. The entire mouse heart can be
imaged with this technique in less than 5 minutes, using minimal sedation. This report demonstrates the ability of MRI to be used for high-throughput
applications, and compete with echocardiography, in the basic science as well as and clinical settings.
1438. Inflow Inversion Recovery MR Angiography of Renal Arteries at 3.0 T: A Feasibility Study
Hiromitsu Onishi 1 , Tonsok Kim 1 , Masatoshi Hori 1 , Takahiro Tsuboyama 1 , Atsushi Nakamoto 1 , Hiroki
Higashihara 1 , Mitsuaki Tatsumi 1 , Kaname Tomoda 1 , Mitsuhiro Uike 2 , Shoji Nakagami 2
1 Department of Radiology, Osaka University Graduate School of Medicine, Suita, Osaka, Japan; 2 MR Sales & Marketing Department,
GE Healthcare Japan, Hino, Tokyo, Japan
The aim of the present study was to evaluate the feasibility of noncontrast MR angiography of the renal arteries using an Inflow Inversion Recovery (IFIR)
sequence in healthy volunteers at 3.0 T. In nine of 10 cases, MR angiography with excellent image quality was obtained and both sides of renal arteries were
finely delineated including peripheral branches. In four of 10 cases, two left renal arteries were observed. In addition, in one of four, two right renal arteries
were also observed. The renal arteries were finely delineated by means of noncontrast MR angiography using an IFIR sequence at 3.0 T.
1439. 3D Isotropic Non-Contrast Approach for the Assessment of Carotid Arteries Stenosis at 3T
Ravi Teja Seethamraju 1 , Michael Jerosch-Herold 2 , Yiu-Cho Chung 3 , Peter Libby 4 , Marcelo F. Di Carli 5 ,
Raymond Y. Kwong 6
1 MR R and D, Siemens Medical Solutions, USA Inc., Charlestown, MA, United States; 2 Radiology, Brigham and Women's Hospital,
Boston, MA, United States; 3 MR R and D, Siemens Medical Solutions, USA Inc., Columbus, OH, United States; 4 Cardiovascular
Medicine, Brigham and Woman's Hospital, Boston, MA, United States; 5 Nuclear Medicine, Brigham and Women's Hospital, Boston,
MA, United States; 6 Cardiovascular Imaging, Brigham and Women's Hospital, Boston, MA, United States
We present MPRAGE and SPACE as two isotropic 3D non contrast techniques for the measurement of coronary artery stenosis. While both techniques
provide precise measurements of the stenosis, they complement each other with respect to characterization of plaque.
1440. Non-Contrast Time-Resolved MR Angiography Combining Multiple IR and N-1 Subtraction Arterial
Spin Labeling Technique
Tokunori Kimura 1 , Shinichi Kitane 2 , Kazuhiro Sueoka 3
1 MRI Systems Development Department, Toshiba Medical Systems , Otawara, Tochigi, Japan; 2 MRI Systems Development
Department, Toshiba Medical Enginieering, Otawara, Tochigi, Japan; 3 MRI Systems Development Department, Toshiba Medical
Enginieering, Otawara, Tochigi, Japan
In-flow time-resolved MR angiography technique employing non-subtraction arterial spin labeling with multiple IR (mIR) technique was proposed. It was,
however, difficult for mIR to suppress background tissue of wide range of T1 values from fat to CSF. We proposed alternative N-1 subtraction technique
further to suppress background tissue signals while minimizing extra acquisition time. Volunteer brain study was performed on 1.5T imager with 2 mIR
pulses designed to suppress brain tissues. Resulting background signals of fat and brain parenchyma were well suppressed only by adding extra acquisition
time of 16 sec for base image then subtraction.
SAR & Safety
Hall B Tuesday 13:30-15:30
1441. Evaluation of Maximum Local SAR for Parallel Transmission (PTx) Pulses Based on Pre-Calculated
Field Data Using a Selected Subset of "Virtual Observation Points"
Matthias Gebhardt 1 , Dirk Diehl 2 , Elfar Adalsteinsson 3 , Lawrence L. Wald 4 , Gabriele Eichfelder 5
1 Siemens Healthcare, Erlangen, Germany; 2 Siemens Corporate Technology, Erlangen, Germany; 3 Electrical Engineering and
Computer Science, Massachusetts Institute of Technology, Cambridge, MA, United States; 4 Martinos Center for Biomedical Imaging,
Harvard University, Charlestown, MA, United States; 5 Applied Mathematics II, University of Erlangen-Nuremberg, Erlangen,
Germany
This work addresses the complexity problem inherent in local SAR estimation for parallel transmission (pTx) and shows that a relatively small subset of
carefully selected “virtual observation points” is adequate for prediction and control of maximum local SAR in pTx. We tested the proposed algorithm to
detect local SAR maxima by comparison with an exhaustive search over local SAR distribution in numerical simulations of adult male and female subjects
for an 8 channel whole body transmit array. The proposed method of model compression for local SAR successfully captured regions of local SAR maxima,
but with dramatically reduced computation cost.