Patent ID: 7480525

Claim:
A MRI method for identifying the presence and location in a body of a contrast agent or an object with magnetic susceptibility sufficient to induce magnetic field inhomogeneity in spins near the agent or object comprising the steps of: a) placing the body in a static magnetic field, b) applying a sequence of RF excitation and/or refocusing pulses to excite/refocus frequencies for spins containing the contrast agent or the object, c) detecting spin signals at a plurality of different times after excitation and/or refocusing pulses, wherein the detected signals are from spins that have a positive off-resonance and spins that have a negative off-resonance, and spins that are on-resonance, wherein the spin signals from the off-resonance spins and on-resonance spins are simultaneously detected; d) using a mathematical transform on all detected signals to separate detected signals from spins that have a positive off-resonance from detected signals from spins that have a negative off-resonance and from detected signals from spins that are on-resonance; and e) identifying the presence and location in the body of the contrast agent or object using the separated detected signals from spins that have a positive off-resonance and/or signal from spins that have a negative off-resonance.