ELECTRONIC POSTER - ismrm

Spectroscopic Localization & Imaging Methodology
Hall B Monday 14:00-16:00 Computer 14
14:00 3372. In Vivo 31P-MRS at 7T by Single Voxel E-ISIS with GOIA Selection Pulses
Wolfgang Bogner 1 , Marek Chmelik 1 , Ovidiu Cristian Andronesi 2 , Stephan Gruber 1 ,
Siegfried Trattnig 1
1 MR Center of Excellence, Radiology, Medical University, Vienna, Austria; 2 Martinos Center for Biomedical
Imaging, Radiology, Massachusetts General Hospital, Havard Medical School, Charlestown, MA, United States
An image-selected in vivo spectroscopy (ISIS) sequence was developed for acquisition of localized 31P-MRS at 7T in vivo. For
accurate localization (negligible contamination and chemical shift error) even with B1 inhomogeneous surface coils gradient offset
independent adiabatic (GOIA) inversion pulses with high bandwidth were used. To allow short TR without increases in contamination
due to “T1 smearing” an E-ISIS acquisition scheme was combined with adiabatic BIR-4 excitation. This allows localized 31P-MRS in
clinically feasible measurement time (~3-4 min) and good spatial resolution (~2-2.5 cm isotropic) with high reproducibility.
14:30 3373. Faster T 1 Relaxation Times Allow Additional SNR-Per-Unit-Time Optimization in
31 P MRSI at 7T
Marek Chmelík 1,2 , Wolfgang Bogner, 2,3 , Stephan Gruber, 2,3 , Siegfried Trattnig, 2,3 ,
Martin Krššák, 2,3
1 Department of Radiology, Medical University of Vienna, Vienna, Austria; 2 MR Centre of Excellence, Medical
University of Vienna, Vienna, Austria; 3 Department of Radiology, Medical University of Vienna, Vienna,
Austria
It has been shown that in vivo muscle 31 P T 1 relaxation times decrease at higher magnetic field (7T) due to higher contribution of
chemical shift anisotropy. The purpose of this study was to compare and optimize SNR-per-unit-time of 31 P 3D MRSI in the human
calf at 3T and 7T. Phantom experiments with comparable T 1 times showed 94% increase of SNR-per-unit-time whereas in vivo
muscle SNR-per-unit time was increased by 140%, partly due to shorter T 1 relaxation. Both higher magnetic field and shorter T 1
relaxation time contribute to improvement of 31 P MRSI SNR-per-unit-time at 7T.
15:00 3374. Outer Volume Suppression (OVS) for Single Voxel Spectroscopy (SVS) at 7 Tesla
Using Interleaved B1 Shim Settings
Irina Brote 1,2 , Stephan Orzada 1,2 , Andreas K. Bitz 1,2 , Tom Scheenen 1,3 , Oliver Kraff 1,2 ,
Stefan Maderwald 1,2 , Mark E. Ladd 1,2
1 Erwin L. Hahn Institute for MRI, Essen, Germany; 2 Department of Diagnostic and Interventional Radiology
and Neuroradiology, University Hospital Essen, Essen, Germany; 3 Department of Radiology, Radboud
University Nijmegen Medical Center, Nijmegen, Netherlands
High-field magnetic resonance spectroscopy (MRS) should provide enhanced neurochemical information based on increased
sensitivity and higher spectral resolution. Problems arising in high-field MRI, such as B0 and B1 inhomogeneities, may however
decrease spectral resolution and SNR. Multi-channel transmit systems have been introduced to overcome problems concerning B1
inhomogeneity. One multi-channel transmit method is RF shimming. In this study, this method is used for outer volume supression
(OVS) at 7T in single voxel spectroscopy (SVS) using two interleaved RF shim settings. A suppression of the outer volume signals of
more than 90% is achieved.
15:30 3375. 31P Magnetic Resonance Spectroscopy and Imaging at 7T and Signal Dependence
on Brain Tissue Types
Manoj K. Sammi 1 , Yosef Berlow 1,2 , Thomas Barbara 1 , John Grinstead 1,3 , Dennis
Bourdette 4 , William D. Rooney 1,2
1 Advanced Imaging Research Center, Oregon Health & Science University, Portland, OR, United States;
2 Department of Behavioral Neuroscience, Oregon Health & Science University; 3 Siemens Medical Solutions;
4 Department of Neurology, Oregon Health & Science University
Methodology development for quantitative phosphorous MRSI in human brain at 7T
Tuesday 13:30-15:30 Computer 14
13:30 3376. Tract-Based Spectroscopy of the Cingulum at 7 Tesla
René Mandl 1 , Martijn van den Heuvel 1 , Dennis Klomp 2 , Vincent Boer 2 , Jeroen Siero 3 ,
Peter Luijten 2 , Hilleke Hulshoff Pol 1
1 Psychiatry, Rudolf Magnus Institute of neuroscience, UMC Utrecht, Utrecht, Netherlands; 2 Radiology, UMC
Utrecht, Utrecht, Netherlands; 3 Neurosurgery, Rudolf Magnus Institute of neuroscience, UMC Utrecht, Utrecht,
Netherlands
Usage of fiber tracking for positioning and analyzing high spatial resolution 2D Chemical Shift Images of the cingulum at 7 Tesla.