METHOD FOR MAGNETIC RESONANCE SPECTROSCOPIC IMAGING WITH MULTIPLE SPIN-ECHOES

摘要

A nuclear magnetic resonance pulse sequence to provide spectral encoding so that the resulting series of spin-echoes each include both spatial and spectral information for spectroscopic imaging. Atoms within the object are excited and may then be spatially encoded, as by a phase encoding gradient. A series of refocusing pulses is then applied, inducing a respective series of spin-echoes. Spectral information is directly encoded in the spin-echo signals. The multiple spin-echoes may be used for sampling different points of k-space, and/or for increasing the signal-to-noise ratio by averaging. In an alternative embodiment, the present invention produces compound weighted spectroscopic images by selecting the period between refocussing pulses according to the coupling constant of a group contained in the compound; thereby, the signal of the selected compounds modulate with a known frequency different for compounds with different coupling constants.