MAGNETIC RESONANCE IMAGING EQUIPMENT

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PROBLEM TO BE SOLVED : To improve S/N of an image by reducing the effect of nonuniformity of a static magnetic field and to provide an MRI image suppressing fat signals in the imaging by a high-speed spin echo sequence applying a selective excitation pulse.SOLUTION : After RF excitation pulse is impressed on a nuclear spin of a region of interest of a subject placed under a pulse sequence static magnetic field to generate transverse magnetization, at a timing when phases of the transverse magnetization in one component and the other component comprising an excited tissue intersect, RF recovery pulse is impressed to convert the transverse magnetization of one component into longitudinal magnetization. Then, when a half time of a desired echo time is elapsed, a re-convergence pulse is impressed to re-converge the component left as the lateral magnetization to measure a phase-encoded echo signal as the spin echo. The re-convergence pulse is repeated for every echo time.