Martin A Aleksiev¹, Martin Krämer², Nicholas M Brisson³, Marta B Maggioni¹, Georg N Duda³, and Jürgen R Reichenbach^1
1Medical Physics Group, Institute of Diagnostic and Interventional Radiology, Jena University Hospital - Friedrich Schiller University Jena, Jena, Germany, ²Institute of Diagnostic and Interventional Radiology, Jena University Hospital - Friedrich Schiller University Jena, Jena, Germany, ³Julius Wolff Institute, Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Berlin, Germany

An MRI-safe device guiding knee motion/loading with a rotary encoder was used during MRI measurements of multiple knee flexion-extension cycles using radial gradient echo imaging with the golden-angle as a radial increment. Reproducibility of knee motion was investigated and anatomical CINE images were reconstructed for different knee angles by synchronizing the encoder data with the MRI data and selective gating, enabling evaluation of musculoskeletal conditions.

Jerome Allard¹, Alexis Amadon², Guy Aubert¹, Jean Belorgey¹, Christophe Berriaud¹, Cédric Bonnelye², Romain Boudoin¹, Nicolas Boulant², Thierry Boussuge¹, Fawzi Boumezbeur², Philippe Brédy¹, Peter Dietz³, Guillaume Dilasser¹, Yannick Drouen¹, Olivier Dubois¹, Sandrine Faict-Bastin¹, Ignacio Gonzalez Insua³, Vincent Gras², Quentin Guihard¹, Patrice Guiho¹, Jean-Christophe Guillard¹, Vincent Jannot¹, François-Paul Juster¹, Felix Koeber³, Brice Koestel⁴, Denis Le Bihan², René Leboeuf¹, Cécile Lerman², Frédéric Leprêtre², Ange Lotodé¹, François Nunio¹, Lionel Quettier¹, Hermann Landes⁵, Hervé Lannou¹, Aurélien Massire⁴, Franck Mauconduit², Frédéric Molinié¹, Hubert Neyrial¹, Cédric Péron¹, Luc Renou⁴, Arnaud Roger¹, Philippe Rouffiat⁴, Wolfram Ruth³, Thierry Schild¹, Patrick Sieber³, Mathieu Santin^6,7, Martin Schroeder³, Loris Scola¹, Armand Sinanna¹, Vadim Stepanov¹, Mathieu Szmigiel¹, Olivier Tellier¹, Robert Touzery¹, Pierre Védrine¹, Alexandre Vignaud², Christian Walter¹, and Karsten Wiclow^3
1University of Paris-Saclay, CEA, Irfu, Gif sur Yvette, France, ²University of Paris-Saclay, CEA, CNRS, BAOBAB, NeuroSpin, Gif sur Yvette, France, ³Siemens Healthcare GmbH, Erlangen, Germany, ⁴Siemens Healthcare SAS, Saint-Denis, France, ⁵Ensimtech, Buckenhof, Germany, ⁶Sorbonne University, Institut du Cerveau - Paris Brain Institute - ICM, INSERM, CNRS, Paris, France, ⁷ICM, Centre de NeuroImagerie de Recherche – CENIR, Paris, France

The Iseult project started in 2001 and is a collaborative effort involving CEA and the University of Freiburg in academics, Guerbet, Siemens Healthineers and Bruker Biospin as industrial partners. One central aspect of the project has been the design by CEA of a whole-body magnet of 11.7T field strength with a 90-cm wide bore. After nearly 20 years of research and development, prototyping, integration and tests, first images have been acquired with this unique MRI scanner. Some key validation results are presented here. 

Simon Schmidt¹, Arcan Erturk¹, Russell L Lagore¹, Andrea Grant¹, Armin Nagel², Stefan Zbyn¹, and Gregory J Metzger^1
1Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States, ²Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany

Performing sodium and proton imaging in the same study can provide a wealth of unique multinuclear insights for the study of pathologies and their treatment. However, the coils to perform such studies in the human body are limited and none were validated for human use at 10.5T until now.  While both nuclei can benefit from increased SNR at 10.5T sodium suffers from low SNR due to the lower gyromagnetic ratio and natural abundance in the human body compared to ¹H. First in-vivo results are presented for a 10.5T sodium-proton torso array following a safety validation study determining safe operating limits.   

Christian R. Meixner¹, Nico Egger¹, Lena V. Gast¹, Andreas K. Bitz², Titus Lanz³, Ralph Kimmlingen⁴, Laurent Ruck¹, Jürgen Herrler⁵, Michael Uder¹, and Armin M. Nagel^1,6
1Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander- Universität Erlangen-Nürnberg (FAU), Erlangen, Germany, ²Faculty of Electrical Engineering and Information Technology, University of Applied Sciences, Aachen, Germany, ³Rapid Biomedical GmbH, Rimpar, Germany, ⁴Siemens Healthcare GmbH, Erlangen, Germany, ⁵Department of Neuroradiology, University Hospital Erlangen, Friedrich-Alexander- Universität Erlangen-Nürnberg (FAU), Erlangen, Germany, ⁶Division of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany

In the human kidneys, the cortico-medullary sodium gradient plays an important role as it is essential for the concentration of urine and changes may indicate renal malfunction. However, quantitative ²³Na MRI requires high-quality ¹H MRI, since this facilitates co-registration and correction of partial volume effects, which is needed for body imaging in particular. We therefore show the feasibility of high-quality renal proton and sodium imaging using an 8Tx/16Rx ¹H transceiver array that can be combined with a ²³Na four-rung birdcage coil in a single setup.

Leonard W.F. Seelen^1,2, Lieke van den Wildenberg¹, Ayhan Gursan¹, Tijl A. van der Velden¹, Mark Gosselink¹, Martijn Froeling¹, Wybe J.M. van der Kemp¹, Firdaus A.A. Mohamed Hoesein³, Nadia Haj Mohammad⁴, I. Quintus Molenaar², Hjalmar C. van Santvoort², Dennis W.J. Klomp¹, and Jeanine J. Prompers^1
1Dept. of Radiology, University Medical Center Utrecht, Utrecht, Netherlands, ²Dept. of Surgery, UMC Utrecht Cancer Center and St Antonius Hospital Nieuwegein: Regional Academic Cancer Center Utrecht, Utrecht University, Utrecht, Netherlands, ³Dept. of Radiology, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands, ⁴Dept. of Medical Oncology, UMC Utrecht Cancer Center, Regional Academic Cancer Center Utrecht, Utrecht University, Utrecht, Netherlands

Early response assessment for patients with pancreatic cancer receiving chemotherapy is limited. Detection of alterations in ³¹P metabolite levels during treatment could change this perspective. However, to date ³¹P MRS has not yet been demonstrated in the human pancreas in vivo. Here we show in-vivo ³¹P MRSI data in the pancreas of healthy subjects, using a ³¹P whole-body transmit coil in combination with a 16-channel receive array at 7T, and show moderate to good test-retest reliability. In addition, we demonstrate the feasibility of performing ³¹P MRSI in a patient with pancreatic cancer before and after chemotherapy.

Max Lutz¹, Christoph Stefan Aigner¹, Sebastian Dietrich¹, Sebastian Flassbeck^2,3, Constance G. F. Gatefait¹, Christoph Kolbitsch¹, and Sebastian Schmitter^1,4,5
1Physikalisch-Technische Bundesanstalt, Braunschweig and Berlin, Germany, ²Dept. of Radiology, Center for Biomedical Imaging, New York, NY, United States, ³Center for Advanced Imaging Innovation and Research, New York, NY, United States, ⁴Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany, ⁵Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States

At 7T, power restrictions are a major limitation to accurately map the absolute transmit magnetic field (B₁⁺) in the body. To overcome this, we investigate an absolute B₁⁺ mapping method with low RF power using magnetic resonance fingerprinting (MRF). Measurements are done in a phantom at 3T and in-vivo in the liver at 7T. Resulting maps are compared to the actual flip angle (AFI) method. The obtained results show good agreement between the two methods, while the MRF approach seems to perform better in regions of low B₁⁺ amplitude. Motion robustness introduced by a radial acquisition scheme enables free-breathing measurements.

Wyger Brink¹, Marius Staring², Rob Remis³, and Andrew Webb^1
1C.J. Gorter Center for High Field MRI, dept. of Radiology, Leiden University Medical Center, Leiden, Netherlands, ²Division of Image Processing, dept. of Radiology, Leiden University Medical Center, Leiden, Netherlands, ³Circuits and Systems group, dept. of Microelectronics, Delft University of Technology, Delft, Netherlands

This work presents a method for local SAR and B₁⁺ prediction using only a 9 seconds long localizer as input. The total procedure can be executed in less than 30 seconds for a birdcage setup and less than 45 seconds for an eight-channel PTx configuration, enabling seamless integration into the MR workflow.

Rui Tian¹, Alexander Loktyushin¹, Kai Buckenmaier¹, Theodor Steffen¹, and Klaus Scheffler^1,2
1High-Field MR center, Max Planck Institute for Biological Cybernetics, Tübingen, Germany, ²Department for Biomedical Magnetic Resonance, University of Tübingen, Tübingen, Germany

A recent idea of spread spectrum MRI utilizes rapid modulations of localized magnetic fields to speed up image acquisitions. To push this concept further, we experimentally demonstrated 2D FLASH scans at 9.4T accelerated by 3-fold with modulation of a newly built 8-channel local B₀ coil array, and 6-fold together with parallel imaging. Moreover, for FLASH and single shot spiral acquisitions, we designed and simulated another two modulation schemes for the B₀ coil array to further investigate the advantages of independent control over each local coil for imaging acceleration.