An RF coil design to enable quintuple nuclear whole‐brain MRI

Abstract

PurposeTo bring metabolic imaging based on multi‐NMR toward practical use from the RF hardware perspective.MethodsA highly integrated RF coil is designed for whole‐brain MRI and MRS targeted to five nuclear species: 1H, 19F, 31P, 23Na, and 13C. Dipole antennas and closely loaded local receiver loops are combined in this setup.ResultsHigh‐quality in vivo scan results of 1H, 31P, 23Na, and 13C on healthy volunteers have been achieved. For 1H, the transmit efficiency is 77% of a single‐tuned commercial head coil (NOVA 8‐transmit [Tx]/32‐receive [Rx]; NOVA Medical, Wilmington, MA, USA). For 31P, 110% SNR of a dual‐tuned close‐fit head‐birdcage was achieved at the center of the subject, based on MR experiments on a phantom. For 31P, 23Na, and 13C, bench measurements indicate SNR loss of 15%, 27%, and 30% compared with single‐tuned conditions. 19F performance has been proven to be similar to that of 1H through bench tests and electromagnetic simulations.ConclusionWith this device, 1H‐based anatomic images that are expected to meet clinical requirements, as well as high‐quality multi‐NMR images and spectra, can be acquired within one scan session without hardware replacement or patient repositioning, enabling morphologic and metabolic MRI within acceptable scan time.