METHOD FOR CORRECTING SUSCEPTIBILITY-INDUCED IMAGE ARTIFACTS IN MRI AFTER PROSPECTIVE MOTION CORRECTION

摘要

A method of magnetic resonance imaging (MRI), wherein a body part (203) of an animal or human subject (S) in an imaging volume is imaged by acquiring a plurality of spatially-encoded MR signals from the imaging volume where susceptibility-induced field deviations reduce the homogeneity of the main magnetic field B0, and wherein a prospective motion correction (402) is applied, updating the imaging volume between the acquisition of the said spatially-encoded MR signals based on a monitored position of the body part (203), is characterized by the following steps: a) forming a susceptibility model (305, 403) of at least part of the subject (S), including the imaged body part (203), by using a structural magnetic resonance image (301) of the said part of the subject (S) and/or prior knowledge of the anatomy of the subject (S); b) computing the susceptibility-induced field deviations (404) present in the imaging volume at each time MR signals are acquired using the susceptibility model (305, 403) and the knowledge of a monitored position and monitored orientation (401) of the said part of the subject (S) at the said time; c) using of the information about the susceptibility-induced field deviations (404) derived in b) for image correction (406), in particular correction of image distortions and/or intensity modulations. The invention improves the quality of magnetic resonance imaging of moving subjects.