| 摘要 |
An NMR diagnostic apparatus and method for producing a high spatial resolution image of a thick, predetermined region of an object under NMR examination. A static magnetic field is applied to the object along its longitudinal axis. A Gz magnetic field gradient is applied to the object along the longitudinal axis for a first time period. This causes magnetizations of individual nuclear spins within the object to rotate at different phases depending upon the position of the nuclei within the predetermined region of the object. Radio frequency pulses are then applied along the longitudinal axis of the object, in the absence of any magnetic field gradient. The RF pulses excite the nuclei within the predetermined region. During a second time period, a magnetic field gradient Gxy is applied to the object in a direction transverse to the longitudinal axis. Finally, NMR signals are received from the predetermined region of the object and indicate the relative density and position of the nuclei within the object. From such NMR signals, a two-dimensional projection image of the predetermined region is obtained.
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