Dual‐frequency resonant coil design for low‐γ X‐nuclear and proton magnetic resonance imaging at ultrahigh fields
Year: 2023
Type: article
Abstract: Low‐γ X‐nuclear MRS and imaging have played a key role in studying metabolism and physiopathology, especially at ultrahigh fields. We design and demonstrate a novel and simple dual‐frequency RF resonant coil that can operate at both low‐γ X‐nuclear and proton frequencies. The dual‐frequency resonant coil comprises an LC coil loop and a tuning‐matching circuit bridged by two short wires of the desired length to generate two resonant modes: one for proton MRI and the other for low‐γ X‐nuclear MRS imaging with a large difference in their Larmor frequencies at ultrahigh fields. The coil parameters for the desired coil size and resonant frequencies can be determined via numerical simulations based on LC circuit theory. We designed, constructed, and evaluated several prototype surface coils and quadrature array coils for 1 H and 2 H or 17 O imaging, with small‐sized (diameter ≤ 5 cm) coils evaluated using a 16.4 T animal scanner, and a large‐sized (15 cm diameter) coil on a 7 T human scanner. All coils could be tuned/matched and driven in the single coil or array coil mode to the resonant frequencies of 1 H (698 and 298 MHz), 2 H (107 and 45.8 MHz), or 17 O (94.7 and 40.4 MHz) for imaging measurements and evaluation at 16.4 and 7 T, respectively. The dual‐frequency resonant coil or array provides adequate detection sensitivity for 1 H MRI and excellent performance for low‐γ X‐nuclear MRS imaging applications, and excellent coil decoupling efficiency between the array coils at both resonant frequencies with an optimal geometric overlap. It provides a simple, cost‐effective dual‐frequency RF coil solution to perform low‐γ X‐nuclear MRS imaging for preclinical and human applications, especially at ultrahigh fields.
Source: NMR in Biomedicine
DOI: 10.1002/nbm.4930
Institution: University of Minnesota
Language: English
Subfield: Radiology, Nuclear Medicine and Imaging
Field: Medicine
Domain: Health Sciences
Open Access status: hybrid
Estimated APC paid: $5,150
Awards: Advancing simultaneous fMRI-multiphoton imaging technique to study brain function and connectivity across different scales at ultrahigh field, Breaking Spatiotemporal Barriers of MR Imaging Technologies to Study Human Brain Function and Neuroenergetics, Institutional Center Cores for Advanced Neuroimaging, Ultra High Field (16.4 Tesla) Animal MRI/MRS System, Integrated fMRI Methods to Study Neurophysiology and Circuit Dynamics at Laminar and Columnar Level, Technology to Realize the Full Potential of UHF MRI, Computer Aided Diagnostic System for Prostate Cancer Detection Using Quantitative Multiparametric MRI, Development of Quantitative Deuterium MRS Imaging for Human Brain Tumor Application at Ultrahigh Field
OpenAlex ID: W4327892787