Magnetic resonance imaging apparatus and method for adjusting excitation region

摘要

In imaging using 2-dimensional selective excitation pulses, regardless of applications thereof, a technique for obtaining a high quality image is provided.;In the technique, a 2-dimensional selective excitation sequence is carried out while changing a coefficient for determining the cylinder diameter of a region excited by the 2-dimensional selective excitation sequence and a time difference for determining an offset position.;The obtained excitation region and a desired region are compared with each other, and the coefficient and time difference with which the obtained excitation region and the desired region match each other are determined to be the optimum ones.;The determination processing may be performed as an initial adjustment, may be performed according to need in each imaging, or may be performed on a per-application basis.

主权项

1. A magnetic resonance imaging apparatus which collects echo signals generated by applying a high-frequency magnetic field and a gradient magnetic field to an object to be examined, which has been placed in a static magnetic field, in accordance with a predetermined pulse sequence and reconstructs an image from the collected echo signals, comprising:
an adjustment unit configured to adjust a profile of an excitation region to be excited by a local excitation sequence, the adjustment unit using (a) a profile adjustment value of the local excitation sequence and (b) a profile adjustment value table in which profile parameters associated with corresponding adjustment values of the local excitation sequence for exciting the excitation region to obtain a specific profile are stored, a profile adjustment value calculating unit configured to calculate the profile adjustment value of the local excitation sequence, for exciting the excitation region to have an excitation region profile specified by an operator, and a determination unit configured to determine whether or not a corresponding adjustment value associated with a combination of the profile parameters corresponding to the excitation region profile specified by the operator is stored in the profile adjustment value table, wherein the profile adjustment value calculating unit calculates the profile adjustment value of the local excitation sequence when the determination unit determines that the corresponding adjustment value associated with the profile parameters corresponding to the excitation region profile specified by the operator is not stored in the profile adjustment value table.