Use of navigator echoes for the correction of motion artifacts in MRI

摘要

In a magnetic resonance imaging method in which after irradiating RF pulses (201, 2011, 2012) of magnetic resonance frequencies into an object to be inspected, a sequence of detecting echo signals (207) sequentially and a step of reconstructing an image by making use of the obtained echo signals (207) are repeated in parallel, and an animating image is obtained by successively renewing a part of the echo signals (207) used for reconstructing the previous image, a navigator echo (3021, 3022) is generated for every irradiation of the RF pulses (201, 2011, 2012) and is detected, a navigator echo which is served as a reference for correcting phases of the echo signals (207) used for the image reconstruction is successively renewed for every image, and the phases of the echo signals (207) are corrected based on the renewed navigator echo (3021, 3022) for every image to obtain the same. Thereby, a reference time for correcting object motion by making use of navigator echoes (3021, 3022) is set short and artifacts due to an object motion is reduced with an accuracy corresponding to a high temporal resolution. Thus, an MRI method which permits reduction of artifacts due to object motions while keeping a high temporal resolution for an MRI of animating images is provided.