New Horizons in Hyperpolarized 13C MRI

Abstract

Hyperpolarization techniques significantly enhance the sensitivity of magnetic resonance (MR) and thus present fascinating new directions for research and applications with in vivo MR imaging and spectroscopy (MRI/S). Hyperpolarized 13C MRI/S, in particular, enables real-time non-invasive assessment of metabolic processes and holds great promise for a diverse range of clinical applications spanning fields like oncology, neurology, and cardiology, with a potential for improving early diagnosis of disease, patient stratification, and therapy response assessment. Despite its potential, technical challenges remain for achieving clinical translation. This paper provides an overview of the discussions that took place at the international workshop “New Horizons in Hyperpolarized 13C MRI,” in March 2023 at the Bavarian Academy of Sciences and Humanities, Munich, Germany. The workshop covered new developments, as well as future directions, in topics including polarization techniques (particularly focusing on parahydrogen-based methods), novel probes, considerations related to data acquisition and analysis, and emerging clinical applications in oncology and other fields.

MRI Application and Challenges of Hyperpolarized Carbon-13 Pyruvate in Translational and Clinical Cardiovascular Studies: A Literature Review

“…Currently, hyperpolarized cardiac magnetic resonance imaging (CMR) can provide additional information that current myocardial viability assessments are unable to provide [13]. Indeed, CMR hyperpolarized 13 C-pyruvate could potentially give additional information compared to conventional CMR and/or cardiac positron emission tomography (PET) due to the added metabolic measurements available [10,14]. The current results suggest that hyperpolarized CMR holds great potential, so much so that clinical adoption is starting to be proposed [15].…”

“…Hyperpolarization techniques are able to enhance signal intensities by several orders of magnitude and thus largely overcome the major disadvantage of relatively low sensitivity [9]. Applications of hyperpolarization techniques include metabolic imaging, cancer detection, and studying molecular processes in real time [10]. Such in vivo studies have been carried out by researchers both in animals and, much more recently, in humans.…”

“…It means that if for 1 H the sample noise dominates, 13 C frequency has relatively more noise contribution from the coil with respect to sample [85], meaning that coil design has a bigger impact [57], although sample noise still is likely the dominant contributor for human/pig-sized coils [51]. However, the purchase of such 13 C coils can be prohibitive for most centers [10]; therefore, homemade coil-building can be a cheaper solution for performing hyperpolarized MR experiments.…”

Molecules, Up Your Spins!

“…These limitations primarily stem from the prevalence of hardware optimized for detecting protons ( 1 H) and the absence of refined pulse sequences for effective polarization transfer, crucial for improving the SNR of heteronuclear signals. Additionally, hyperpolarization-enhanced NMR/MRI necessitates interdisciplinary working groups and requires advanced infrastructure [56].…”

“…The first proposals for using hyperpolarized contrast agents emerged in the early 1990s, but the steady stream of research publications has (up to date) not been sufficient to convince practicing physicians of their utility. As of 2024, the number of hospitals in the world equipped with the necessary devices and expertise to observe metabolic transformations using hyperpolarization-enhanced 13 C MRI remains fewer than 20 [56]. While the principles of the dDNP methodology have been known since 2003 [19], the anticipated widespread clinical application of this method has not materialized, despite advancements in other research areas driven by Moore's Law [57].…”