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arXiv · 2407.01189

A Bore-Integrated Patch Antenna Array for Whole-Body Excitation in Ultra-High-Field Magnetic Resonance Imaging

Svetlana S. Egorova·Nikolai A. Lisachenko·Egor I. Kretov·Stanislav B. Glybovski·Georgiy A. Solomakha
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Abstract

Objective: To develop and evaluate a bore-integrated patch antenna array designed for whole-body excitation in ultra-high-field (UHF) magnetic resonance imaging (MRI) with improved transmit efficiency and address the limitations of existing RF coil designs. Methods: The proposed patch antenna array utilizes the MRI bore's RF shield as a functional component to enhance the RF magnetic field ($B_1^+$) distribution. Numerical simulations were conducted to compare the performance of the patch antenna array to bore-integrated stripline and local dipole arrays. A decoupling structure was implemented to minimize coupling between adjacent patch antennas. The performance of the patch array was evaluated experimentally. Results: The proposed patch array provides 3.9 times higher averaged transmit (Tx) efficiency in the CP mode and 3.0 times higher for the phase shimming regime versus the bore-integrated stripline array. Conclusion: Compared to the stripline array, the bore-integrated patch antenna array offers significant improvements in Tx efficiency for whole-body UHF MRI. Significance: The findings support the feasibility of integrating arrays into the RF shield of MRI scanners. This could broaden the clinical use of UHF body MRI technology.

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Svetlana S. Egorova, Nikolai A. Lisachenko, Egor I. Kretov, Stanislav B. Glybovski, Georgiy A. Solomakha. 2024-07-01. A Bore-Integrated Patch Antenna Array for Whole-Body Excitation in Ultra-High-Field Magnetic Resonance Imaging. https://arxiv.org/abs/2407.01189

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