title: A 32-Channel Head Coil Array with Circularly Symmetric Geometry for Accelerated Human Brain Imaging.
abstract: The goal of this study is to optimize a 32-channel head coil array for accelerated 3T human brain proton MRI using either a Cartesian or a radial k-space trajectory. Coils had curved trapezoidal shapes and were arranged in a circular symmetry (CS) geometry. Coils were optimally overlapped to reduce mutual inductance. Low-noise pre-amplifiers were used to further decouple between coils. The SNR and noise amplification in accelerated imaging were compared to results from a head coil array with a soccer-ball (SB) geometry. The maximal SNR in the CS array was about 120% (1070 vs. 892) and 62% (303 vs. 488) of the SB array at the periphery and the center of the FOV on a transverse plane, respectively. In one-dimensional 4-fold acceleration, the CS array has higher averaged SNR than the SB array across the whole FOV. Compared to the SB array, the CS array has a smaller g-factor at head periphery in all accelerated acquisitions. Reconstructed images using a radial k-space trajectory show that the CS array has a smaller error than the SB array in 2- to 5-fold accelerations.
authors.affiliation: Institute of Biomedical Engineering, National Taiwan University, Taipei, Taiwan.
authors.forename: Ying-Hua
authors.initials: YH
authors.lastname: Chu
authors.affiliation: Institute of Biomedical Engineering, National Taiwan University, Taipei, Taiwan.
authors.forename: Yi-Cheng
authors.initials: YC
authors.lastname: Hsu
authors.affiliation: Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, United States of America.|Institute for Medical Physics and Radiation Safety, Dept. of Life Science Engineering, Mittelhessen University of Applied Sciences, Gießen, Germany.
authors.forename: Boris
authors.initials: B
authors.lastname: Keil
authors.affiliation: Institute of Neuroscience, National Yang Ming University, Taipei, Taiwan.
authors.forename: Wen-Jui
authors.initials: WJ
authors.lastname: Kuo
authors.affiliation: Institute of Biomedical Engineering, National Taiwan University, Taipei, Taiwan.
authors.forename: Fa-Hsuan
authors.initials: FH
authors.lastname: Lin
mesh_terms: D001921:Brain / Q000502:physiology*; D004867:Equipment Design; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000295:instrumentation* / Q000379:methods*; D059629:Signal-To-Noise Ratio