Magnetic resonance measurement

摘要

PCT No. PCT/GB89/00966 Sec. 371 Date Apr. 22, 1991 Sec. 102(e) Date Apr. 22, 1991 PCT Filed Aug. 18, 1989 PCT Pub. No. WO90/02344 PCT Pub. Date Mar. 8, 1990.In nuclear magnetic resonance spectroscopy spatial localization of the output signal is achieved by using gradient magnetic fields and radio-frequency inversion pulses to define slices through a sample from which a signal is obtained. The use of intersecting slices allows the field of view to be reduced to the region of intersection to study a localized volume of interest in the sample. Conventionally, three orthogonal gradient magnetic fields can be defined by energizing successively three gradient magnetic field coils. With the present invention combinations of the gradient magnetic field coils are energized simultaneously to allow the field of view to be more closely conformed to a described volume of interest. This simultaneous energization allows the field of view to be rotated relative to the axes of the coils and/or allows non-orthogonal intersecting slices to be defined to alter the shape of the field of view at the intersection of the slices. Further, more than three slices may be defined to allow polyhedral fields of view to be defined. The invention is applicable to many modern forms of nuclear magnetic resonance spectroscopy.