Dataset Information

RF coil design for accurate parallel imaging on ¹³ C MRSI using ²³ Na sensitivity profiles.

ABSTRACT:

Purpose

To develop a coil-based method to obtain accurate sensitivity profiles in ¹³ C MRI at 3T from the endogenous ²³ Na. An eight-channel array is designed for ¹³ C MR acquisitions. As application examples, the array is used for two-fold accelerated acquisitions of both hyperpolarized ¹³ C metabolic imaging of pig kidneys and the human brain.

Methods

A flexible coil array was tuned optimally for ¹³ C at 3T (32.1 MHz), with the coil coupling coefficients matched to be nearly identical at the resonance frequency of ²³ Na (33.8 MHz). This is done by enforcing a high decoupling (obtained through highly mismatched preamplifiers) and adjusting the coupling frequency response. The SNR performance is compared to reference coils.

Results

The measured sensitivity profiles on a phantom showed high spatial similarity for ¹³ C and ²³ Na resonances, with average noise correlation of 9 and 11%, respectively. For acceleration factors 2, 3, and 4, the obtained maximum g-factors were 1.0, 1.1, and 2.6, respectively. The ²³ Na profiles obtained in vivo could be used successfully to perform two-fold acceleration of hyperpolarized ¹³ C 3D acquisitions of both pig kidneys and a healthy human brain.

Conclusion

A receive array has been developed in such a way that the ¹³ C sensitivity profiles could be accurately obtained from measurements at the ²³ Na frequency. This technique facilitates accelerated acquisitions for hyperpolarized ¹³ C imaging. The SNR performance obtained at the ¹³ C frequency, compares well to other state-of-the-art coils for the same purpose, showing slightly better superficial and central SNR.

SUBMITTER: Sanchez-Heredia JD

PROVIDER: S-EPMC9328386 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature

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Publications

RF coil design for accurate parallel imaging on <sup>13</sup> C MRSI using <sup>23</sup> Na sensitivity profiles.

Sanchez-Heredia Juan D JD Olin Rie B RB Grist James T JT Wang Wenjun W Bøgh Nikolaj N Zhurbenko Vitaliy V Hansen Esben S ES Schulte Rolf F RF Tyler Damian D Laustsen Christoffer C Ardenkjaer-Larsen Jan H JH

Magnetic resonance in medicine 20220530 3

<h4>Purpose</h4>To develop a coil-based method to obtain accurate sensitivity profiles in <sup>13</sup> C MRI at 3T from the endogenous <sup>23</sup> Na. An eight-channel array is designed for <sup>13</sup> C MR acquisitions. As application examples, the array is used for two-fold accelerated acquisitions of both hyperpolarized <sup>13</sup> C metabolic imaging of pig kidneys and the human brain.<h4>Methods</h4>A flexible coil array was tuned optimally for <sup>13</sup> C at 3T (32.1 MHz), with ...[more]

PMID: 35635156

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Dataset Information

RF coil design for accurate parallel imaging on ¹³ C MRSI using ²³ Na sensitivity profiles.

Purpose

Methods

Results

Conclusion

Publications

RF coil design for accurate parallel imaging on <sup>13</sup> C MRSI using <sup>23</sup> Na sensitivity profiles.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Dataset Information

RF coil design for accurate parallel imaging on 13 C MRSI using 23 Na sensitivity profiles.

Purpose

Methods

Results

Conclusion

Publications

RF coil design for accurate parallel imaging on &lt;sup&gt;13&lt;/sup&gt; C MRSI using &lt;sup&gt;23&lt;/sup&gt; Na sensitivity profiles.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

RF coil design for accurate parallel imaging on ¹³ C MRSI using ²³ Na sensitivity profiles.

RF coil design for accurate parallel imaging on <sup>13</sup> C MRSI using <sup>23</sup> Na sensitivity profiles.