Purpose The goal of this work is to develop and evaluate a single-layer tight-fit 32-element double-tuned loop/dipole transceiver (TxRx) array for human brain 31P MRS at 9.4T, achieving reasonable transmit and receive performance and full-brain coverage at both frequencies. Methods First, we developed numerical models of dual-row TxRx arrays for 31P (loop array) and 1H (coaxial-end folded-end dipole array) frequencies at 9.4T. Next, a multi-tissue voxel model was used to simulate Tx-performance of the arrays and define optimal CP-mode excitation. Following this, the proposed array performance was evaluated by MR measurements both on a phantom and a healthy volunteer. Finally, we compared the proposed array to a previously reported dual-tuned single-row loop-based TxRx array. Results The developed 32-element double-tuned array demonstrated full-brain (including the cerebellum and brain stem) imaging capabilities, reasonable SNR and transmit performance at both frequencies at 9.4T. Conclusion As a proof of concept, we developed a 32-element double-tuned UHF tight-fit TxRx human head array coil for 31P MRS with sufficient 1H performance using a combination of loop and dipole array elements. The proposed array design could also be adapted to higher fields, i.e., 10.5T, 11.7T, and 14T.
@article{arxiv.2604.07187,
title = {Dual-Tuned 31P-1H Dual-Row Loop/Dipole 32-element Transceiver Array for Human Brain Spectroscopy at 9.4T},
author = {G. A. Solomakha and R. Pohmann and F. Glang and S. Mueller and P. I. Valsala and T. Platt and S. Orzada and M. E. Ladd and A. Korzovski and K. Scheffler and N. I. Avdievich},
journal= {arXiv preprint arXiv:2604.07187},
year = {2026}
}