| abstract |
A magnetic resonance system is used to excite high gamma dipoles, such as hydrogen, and lower gamma dipoles, such as phosphorous, to resonate concurrently. A multiply-tuned radio frequency coil (40) is disposed around the region of interest. The multiply-tuned radio frequency coil is tuned to the resonance frequency of the high gamma dipoles and the resonance frequency of the low gamma dipoles. The coil has an inner coil section, defined by a first leg or ring (92) and a second leg or ring (94), which is tuned by added capacitance substantially to the resonance frequency of the low gamma dipole. A first outer coil section which is defined by a third leg or ring (90) and the first leg or ring. A second outer coil section defined by the second leg or ring (94) and a fourth leg or ring (96). The first and second outer sections, together with the inner coil section define a coil which has a co-rotating mode and a counter-rotating mode. Added capacitance is sized such that one of the co-rotating and counter-rotating modes is at the high gamma resonance frequencies. In this manner, a multiply-tuned radio frequency coil is defined which is simultaneously tuned to at least two resonance frequencies. Separate pick-ups (130, 132) for the high and low resonance frequencies enable both signals to be received (66, 70) simultaneously for reconstruction (74) into image representations. |