Methods for two dimensional nuclear magnetic resonance imaging

Abstract

Improved two dimensional nuclear magnetic resonance imaging methods of the present invention are presented which comprise sensitizing a two dimensional slice of an object by standard procedures in a static magnetic field wherein the magnetization of the spins is transverse to the static field, applying a time varying magnetic field gradient to the sensitized two dimensional slice, detecting radiated electromagnetic energy from the two dimensional slice, and reconstructing spin information for each element within a slice from the detected radiated electromagnetic energy. In one aspect, the improvement is the use of an appropriate weighting function in the reconstruction to weight the detected radiated electromagnetic energy signals to compensate for the use of time varying magnetic field gradients that do not sample equal area elements of phase space in equal time intervals. In another independent aspect, almost any magnetic field gradient function may be used, that does not sample equal areas of phase space during equal time intervals, and a procedure defined by which spin information for equal areas of phase space is detected at unequal times. In yet another aspect, a uniquely specified class of time varying magnetic field gradient trajectories are defined which may equal area elements of two dimensional phase space in equal time intervals.