NMR Imaging for Magnets with Large Nonuniformities

Nuclear magnet resonance (NMR) imaging in the presence of large static field nonuniformity is presented. The method involves three steps: field mapping, imaging by a conventional method, and image restoration from nonuniform field influence. Two-dimensional experiments are performed to demonstrate effectiveness of this method, as well as to clarify practical problems in employing the method. Experimental results show that, with this method, images free from distortion can be obtained using a magnet with an order of magnitude greater nonuniformity than magnets commonly used for whole-body imaging.