Dataset Information

Creating a clinical platform for carbon-13 studies using the sodium-23 and proton resonances.

ABSTRACT:

Purpose

Calibration of hyperpolarized ¹³ C-MRI is limited by the low signal from endogenous carbon-containing molecules and consequently requires ¹³ C-enriched external phantoms. This study investigated the feasibility of using either ²³ Na-MRI or ¹ H-MRI to calibrate the ¹³ C excitation.

Methods

Commercial ¹³ C-coils were used to estimate the transmit gain and center frequency for ¹³ C and ²³ Na resonances. Simulations of the transmit B₁ profile of a Helmholtz loop were performed. Noise correlation was measured for both nuclei. A retrospective analysis of human data assessing the use of the ¹ H resonance to predict [1-¹³ C]pyruvate center frequency was also performed. In vivo experiments were undertaken in the lower limbs of 6 pigs following injection of hyperpolarized ¹³ C-pyruvate.

Results

The difference in center frequencies and transmit gain between tissue ²³ Na and [1-¹³ C]pyruvate was reproducible, with a mean scale factor of 1.05179 ± 0.00001 and 10.4 ± 0.2 dB, respectively. Utilizing the ¹ H water peak, it was possible to retrospectively predict the ¹³ C-pyruvate center frequency with a standard deviation of only 11 Hz sufficient for spectral-spatial excitation-based studies.

Conclusion

We demonstrate the feasibility of using the ²³ Na and ¹ H resonances to calibrate the ¹³ C transmit B₁ using commercially available ¹³ C-coils. The method provides a simple approach for in vivo calibration and could improve clinical workflow.

SUBMITTER: Grist JT

PROVIDER: S-EPMC8638662 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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Publications

Creating a clinical platform for carbon-13 studies using the sodium-23 and proton resonances.

Grist James T JT Hansen Esben S S ESS Sánchez-Heredia Juan D JD McLean Mary A MA Tougaard Rasmus R Riemer Frank F Schulte Rolf F RF Kaggie Joshua D JD Ardenkjaer-Larsen Jan Henrik JH Laustsen Christoffer C Gallagher Ferdia A FA

Magnetic resonance in medicine 20200313 4

<h4>Purpose</h4>Calibration of hyperpolarized <sup>13</sup> C-MRI is limited by the low signal from endogenous carbon-containing molecules and consequently requires <sup>13</sup> C-enriched external phantoms. This study investigated the feasibility of using either <sup>23</sup> Na-MRI or <sup>1</sup> H-MRI to calibrate the <sup>13</sup> C excitation.<h4>Methods</h4>Commercial <sup>13</sup> C-coils were used to estimate the transmit gain and center frequency for <sup>13</sup> C and <sup>23</sup> ...[more]

PMID: 32167199

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Dataset Information

Creating a clinical platform for carbon-13 studies using the sodium-23 and proton resonances.

Purpose

Methods

Results

Conclusion

Publications

Creating a clinical platform for carbon-13 studies using the sodium-23 and proton resonances.

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