ISMRM 23rd Annual Meeting & Exhibition • 30 May - 05 June 2015 • Toronto, Ontario, Canada

Combined Educational & Scientific Session

Hyperpolarized C-13 Imaging

SKILL LEVEL: Intermediate

ORGANIZERS: Peter Caravan, Ph.D. & Matthew Merritt, Ph.D.

Monday 1 June 2015

This combined educational/scientific session will provide an introduction to hyperpolarized C-13 MRI,
followed by lectures on the state of the art in hyperpolarized C-13 with
respect to image acquisition & reconstruction and applications in different disease areas.
This will be followed by 5 short talks selected from the scientific abstracts.

Target Audience
Researchers with an interest in technical and applied aspects of hyperpolarized imaging,
and those interested in imaging metabolism and physiology can benefit from this course.

Educational Objectives
Upon completion of this course, participants should be able to:
• Describe what hyperpolarized C-13 imaging is, and what is required to perform hyperpolarized C-13 MR;
• Explain the challenges in hyperpolarized C-13 data acquisition and summarize different approaches to meeting these challenges; and
• Provide at least two examples of how hyperpolarized C-13 imaging can be used to measure metabolic changes in different disease states.

Moderators: Lloyd Lumata, Ph.D., Mor Mishkovsky, Ph.D.
10:45   Introduction to Hyperpolarized C-13 MR: What is it? How Do You Do it?
Matthew Merritt, Ph.D.
11:05   Acquisition & Reconstruction Strategies: State of the Art
Charles H. Cunningham, Ph.D.
11:25   Imaging Metabolism with Hyperpolarized 13C-Labelled Cell Substrates
Kevin M. Brindle, Ph.D.
11:45 0091.   Hyperpolarized [1-13C]octanoate: a probe of myocardial lower case Greek beta-oxidation
Hikari A. I. Yoshihara1,2, Jessica A. M. Bastiaansen2,3, Magnus Karlsson4, Mathilde Lerche4, Arnaud Comment2,5, and Juerg Schwitter1
1Division of Cardiology and Cardiac MR Center, Lausanne University Hospital, Lausanne, Switzerland, 2Center for Biomedical Imaging (CIBM), Lausanne, Switzerland, 3Department of Radiology, Lausanne University Hospital and University of Lausanne, Switzerland, 4Albeda Research ApS, Copenhagen, Denmark, 5Institute of Physics of Biological Systems, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland

The heart is fueled mainly by long-chain fatty acids. We report the in vivo myocardial metabolism of hyperpolarized [1-13C]octanoate, a medium-chain fatty acid. The hyperpolarized signal is short-lived in the blood, but a metabolite signal from [1-13C]acetylcarnitine was observed, indicating the uptake of octanoate into the mitochondria and its lower case Greek beta-oxidation to acetyl-CoA. Additional metabolite signals from [5-13C]glutamate, [5-13C]citrate and [1-13C]acetoacetate were occasionally observed. The acetylcarnitine signal relative to octanoate tended to be lower and more variable in fasted versus fed rats. This study demonstrates that hyperpolarized 13C-labeled medium-chain fatty acids can be used as metabolic probes in the heart.

11:57 0092.   Hyperpolarized 13C-alpha-ketobutyrate, a pyruvate analog
Cornelius von Morze1, Robert A Bok1, Michael A Ohliger1, Daniel B Vigneron1, and John Kurhanewicz1
1Department of Radiology & Biomedical Imaging, UCSF, San Francisco, California, United States

In this work we demonstrate hyperpolarization and rapid in vivo enzymatic conversion of an endogenous structural analog of 13C-pyruvate, 13C-alpha-ketobutyrate, via lactate dehydrogenase (LDH). Based on prior non-MR work and our own initial results, this hyperpolarized probe may exhibit useful selectivity for LDHB-expressed isoforms of LDH, such as heart or kidney LDH.

12:09 0093.   
Slice Blipped EPI Trajectory for Compressed Sensing Acquisition of 3D Time Resolved Imaging of Hyperpolarized [1-13C]Pyruvate and [1-13C]Lactate
Benjamin J. Geraghty1,2, Justin Y.C. Lau1,2, Albert P. Chen3, William Dominguez-Viqueira1, and Charles H. Cunningham1,2
1Imaging Research, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada, 2Dept. of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada, 3GE Healthcare, Toronto, Ontario, Canada

Spectral-spatial excitation can be used for rapid time resolved 3D acquisitions; however, maintaining adequate spatial and temporal resolution is limited by the required field-of-view coverage. Here, we demonstrate a slice blipped EPI compressed sensing acquisition strategy for accelerated 3D time resolved imaging of [1-13C]pyruvate and lactate across a large field-of-view. Image reconstructions of both retrospectively and prospectively 2X undersampled in vivo data is presented. Close agreement is shown between fully and undersampled lactate to pyruvate area under curve ratio.

12:21 0094.   
Parallel Imaging using a Concentric Rings Trajectory and Application to Hyperpolarized 13C MR Spectroscopic Imaging
Wenwen Jiang1, Michael Lustig2, and Peder E.Z. Larson3
1Bioengineering, UC Berkeley/UCSF, Berkeley, CA - California, United States, 2EECS, UC Berkeley, Berkeley, California, United States, 3Radiology and Biomedical Imaging, UCSF, San Francisco, CA - California, United States

The short-lived effect of hyperpolarization of 13C poses severe challenges to develop rapid and robust imaging techniques. The concentric rings trajectory is such a technique for hyperpolarized 13C spectroscopic imaging that it is favorable for parallel imaging for additional acceleration. Preclinical studies have been performed to evaluate the feasibility of using concentric rings hyperpolarized 13C MRSI parallel imaging. Simulation of g-factor maps demonstrates its advantages of the lower noise amplification compared to Cartesian counterpart. Concentric rings trajectory shows great potential to be applied with parallel imaging.

12:33 0095.   Hyperpolarized Metabolic MR Imaging of Acute Myocardial Changes and Recovery Upon Ischemia-Reperfusion
Patrick Wespi1, Darach O h-Ici1,2, Julia Busch1, Lukas Wissmann1, Marcin Krajewski1, Kilian Weiss1, Andreas Sigfridsson1, Daniel Messroghli2, and Sebastian Kozerke1,3
1Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland, 2Department of Congenital Heart Disease and Pediatric Cardiology, German Heart Institute, Berlin, Germany, 3Division of Imaging Sciences and Biomedical Engineering, King's College London, London, United Kingdom

The aim of the present work was to study in vivo the metabolic changes following left coronary artery occlusion. Rats were scanned using hyperpolarized [1-13C] pyruvate before coronary occlusion and directly after reopening of the coronary artery after 15 minutes of ischemia. Scans were repeated throughout the first hour of reperfusion, and then at 1 week following coronary occlusion. Data were correlated to local regional function using cine imaging and to myocardial injury based on late gadolinium enhancement (LGE) imaging. Myocardial metabolism was abnormal in the area-at-risk during the first 60 minutes following ischemia, but returned to normal one week later.

12:45   Adjournment & Meet the Teachers