Patent ID: 7151370

Claim:
A method of separating MRI signals (Sp 1 , Sp 2 ) from two species in an object being imaged comprising the steps of: a) acquiring MRI signals (S 1 , S 2 ) using two balanced SSFP acquisitions in which the two species are at respective phase differences, φ and ν, and in which echo times TE 1 and TE 2 differ, with S 1 =( S p1 −S p2 ) e iφ S 2 =( S p1 −e iν S p2 ) e iφ e 2πi(TE 2 −TE 1 )f where f is a frequency corresponding to field inhomogeniety and susceptibility variations, b) estimating a phase, {circumflex over (φ)}, for voxels in a field of view, and defining species differences as {circumflex over (d)}=Sp 1 −Sp 2 =S 1 e −1{circumflex over (φ)} , and c) using a quadratic expression | S 2 | 2 =S p1 2 +S p2 2 +2 S p1 ·S p2 cos ν and substituting species difference, {circumflex over (d)}, estimating S ^ p2 = - 1 2 ⁢ ⅆ ^ ⁢ + 1 2 ⁢ ⅆ ^ 2 ⁢ + 2 ⁢ ❘ S 2  2 - ⅆ ^ 2 1 + cos ⁢ ⁢ v ⁢ ⁢ and ⁢ ⁢ S ^ p1 = ⅆ ^ ⁢ + S ^ p2 .