Method for adjusting static magnetic field homogeneity, static magnetic field generation device for magnetic resonance imaging, magnetic field adjustment system, and program

摘要

In order to avoid the duplication of the period and cost required for magnetic field adjustment, minimize the magnetic field adjustment period in a final installation site, and achieve highly efficient magnetic field adjustment of a magnet, a method for adjusting the homogeneity of a static magnetic field generated in a measurement space by a static magnetic field generation means by disposing magnetic field correction means for generating a corrected magnetic field with respect to the static magnetic field comprises: a step for measuring the static magnetic field generated by the static magnetic field generation means; a step for expanding the spatial distribution of the measured static magnetic field in a series; a first magnetic field adjustment step for correcting a high-order term irregular magnetic field components expanded in a series; and a second step for adjusting a low-order irregular magnetic field component, the second step being performed after the first adjustment step.

主权项

1. A method for adjusting the homogeneity of a static magnetic field generated by a static magnetic field generation unit in a measurement space by placing a magnetic field correction unit that generates a corrected magnetic field, the method including:
measuring the static magnetic field generated by the static magnetic field generation unit; expanding a spatial distribution of the measured static magnetic field in a series; first magnetic field adjustment for adjusting irregular magnetic field components of high-order terms from among irregular magnetic field components that are expanded in the series; and second magnetic field adjustment for adjusting irregular magnetic field components of low-order terms from among the irregular magnetic field components that are expanded in the series, to be executed after the first magnetic field adjustment, wherein; the static magnetic field generation unit has a shape of a circular cylinder in which the static magnetic field direction is parallel with a longitudinal axis of the circular cylinder, each of the first and second magnetic field adjustments includes placing the magnetic field correction unit along plural virtual lines which are on a virtual circular cylinder that is concentric with the circular cylinder of the static magnetic field generation unit, and said virtual lines are parallel with the axis of the circular cylinder, and the virtual lines on which the magnetic field correction units are placed in the first magnetic field adjustment and the virtual lines on which the magnetic field correction units are placed in the second magnetic field adjustment are arrayed alternately.