Patent ID: 6046589
Filing Date: 2000-04-04
Classification: G01R

Abstract:
A method for magnetic resonance imaging of a density distribution of a first substance and a second substance in a part of a body which is arranged in a substantially uniform, steady magnetic field, the first substance having a J-coupling, which method includes:a) exciting spins of the first substance and the second substance in the part of the body by means of an excitation pulse,b) generating pulse sequences for measurement of MR signals which pulse sequences include a series of successive refocusing pulses and first and second gradients in mutually orthogonal first and a second directions, respectively, the repetition time between the refocusing pulses in said pulse sequences being substantially equal to the reciprocal valuec) fitting measured values of the MR signals in a 3-dimensional data matrix, a first and a second dimension of which correspond to the respective gradients in the first direction and the second direction whereas a third dimension corresponds to a measuring time of an MR signal, andd) determining a density distribution of the first substance or the second substance in the part of the body from the data matrix by means of Fourier transformations,(i) wherein the first gradient is generated in such a manner that along the first dimension of the data matrix a value of the MR signal measured after a refocusing pulse bearing an even sequence number, in the series of successive refocusing pulses, follows a value of the MR signal measured after a refocusing pulse bearing an odd sequence number,(ii) wherein a distance between two adjacently situated grid points along the first dimensions equals n/FOV, where FOV represents the field of view in the first direction, and(iii) wherein non-measured vales in the data matrix are ser to zero.