MR IMAGING USING MOTION-DEPENDENT RADIAL OR SPIRAL K-SPACE SAMPLING

摘要

The invention relates to a method of MR imaging of an object (10) placed in an examination volume of a MR device (1). It is an object of the invention to enable MR imaging using a radial (or spiral) acquisition scheme with a reduced level of motion artefacts. The method of the invention comprises the following sequence of steps: - detecting a momentary motion- induced displacement (Δ) of the object (10); - attributing the detected displacement (Δ) to a motion state (M1-M5), each motion state (M1-M5) corresponding to one of a plurality of contiguous ranges of displacements (Δ); - determining angular coordinates of a radial or spiral k-space profile by incrementing the angular coordinates individually for each motion state (M1-M5) starting from initial angular coordinates; - acquiring the k-space profile; - repeating steps a-d a number of times; and - reconstructing an MR image from at least the k-space profiles attributed to one of the motion states (M1-M5). Moreover, the invention relates to a MR device (1) for carrying out this method as well as to a computer program to be run on a MR device (1).