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Hyperpolarized 13C Metabolic Magnetic Resonance Spectroscopy and Imaging
Published on: December 30, 2016
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Hyperpolarized 13C Spectroscopy with Simple Slice-and-Frequency-Selective Excitation
Geoffrey J Topping1, Irina Heid2, Marija Trajkovic-Arsic3,4,5
1Department of Nuclear Medicine, School of Medicine, Klinikum Rechts der Isar, Technical University of Munich, 81675 Munich, Germany.
Biomedicines
|January 30, 2021
Summary
This study introduces a new method for hyperpolarized Carbon-13 spectroscopy to improve the quantification of cancer metabolites. The technique enhances the detection of low-signal molecules like pyruvate in preclinical cancer models.
Area of Science:
- Biomedical Imaging
- Metabolic Spectroscopy
- Preclinical Oncology
Background:
- Hyperpolarized 13C magnetic resonance spectroscopy (MRS) assesses in vivo metabolism, crucial for cancer research.
- Quantifying low-signal metabolites in preclinical models is challenging due to spectral overlap and excitation bandwidth limitations.
Purpose of the Study:
- To develop an improved method for quantifying metabolites in hyperpolarized 13C spectroscopy.
- To enhance the measurement of injected hyperpolarized [1-13C]lactate and its metabolite [1-13C]pyruvate dynamics in a pancreatic cancer model.
Main Methods:
- Utilized alternating frequency narrow bandwidth (250 Hz) slice-selective excitation at 7 Tesla for 13C spectroscopy.
- Employed spatially offset slices for alternating frequency excitation with simpler radiofrequency pulses.
- Used point-resolved spectroscopy to calibrate 13C frequency from proton signals.
Main Results:
- Successfully isolated the low-signal [1-13C]pyruvate peak from the [1-13C]lactate peak.
- Facilitated improved quantification of the [1-13C]pyruvate signal.
- Simplified data processing for hyperpolarized 13C spectroscopy.
Conclusions:
- The novel excitation scheme enhances metabolite quantification in preclinical cancer models.
- This method offers a simpler approach compared to complex pulse sequences.
- The technique is potentially applicable to other substrates and preclinical models.
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