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Updated: Oct 2, 2025
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Use of a Multi-compartment Dynamic Single Enzyme Phantom for Studies of Hyperpolarized Magnetic Resonance Agents
Published on: April 15, 2016
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A reproducible dynamic phantom for sequence testing in hyperpolarised 13C-magnetic resonance
Rafat Chowdhury1, Marianthi-Vasiliki Papoutsaki1, Christoph A Müller2,3
1Centre for Medical Imaging, Division of Medicine, University College London, London, UK.
The British Journal of Radiology
|March 1, 2022
Summary
A new dynamic phantom system with automated injection improves reproducibility for hyperpolarized 13C-MR imaging metrics. This standardized phantom is crucial for developing pulse sequences and enabling multi-site clinical trials.
Area of Science:
- Medical Imaging
- Biophysics
- Chemical Engineering
Background:
- Hyperpolarized 13C-MR (Carbon-13 Magnetic Resonance) offers metabolic insights but requires robust methods for metric derivation.
- Manual injection in phantom studies introduces variability, hindering pulse sequence development and clinical trial standardization.
- Reproducible experimental setups are essential for advancing hyperpolarized 13C-MR applications.
Purpose of the Study:
- To develop and validate a dynamic phantom system integrated with automated injection for hyperpolarized 13C-MR.
- To reduce experimental variability associated with manual injection in phantom studies.
- To facilitate pulse sequence testing and metric derivation for hyperpolarized 13C-MR.
Main Methods:
- A custom dynamic phantom was fabricated from Ultem and filled with a mixture of nicotinamide adenine dinucleotide and lactate dehydrogenase in phosphate-buffered saline.
- Hyperpolarized [1-13C]-pyruvate was injected into the phantom (n=8) using an automated syringe pump.
- The conversion of pyruvate to lactate was monitored using a 13C imaging sequence.
Main Results:
- The phantom exhibited low coefficients of variation for lactate to pyruvate peak signal heights (11.6%) and dynamic area-under-curve ratios (11.0%).
- The lactate dehydrogenase enzyme rate constant (kP) demonstrated low variance (15.6%).
- The system achieved high reproducibility in quantifying key metabolic metrics.
Conclusions:
- The developed dynamic phantom provides high reproducibility for quantifying hyperpolarized 13C-MR derived metrics.
- This phantom is vital for advancing hyperpolarized 13C-MR pulse sequence development and standardization.
- It enables reliable multi-site hyperpolarized 13C-MR clinical trials by ensuring consistent metric assessment across different locations.
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