Fast automatic linear off‐resonance correction method for spiral imaging

Field inhomogeneity and susceptibility variations, coupled with a long readout, can result in image blurring in spiral imaging. Many correction methods based on a priori off‐resonance information, such as an acquired field map, have been proposed in the literature. Automatic off‐resonance correction methods are alternative approaches that estimate a field map from the image data themselves. In this paper we propose a fast automatic off‐resonance correction method that performs linear correction without acquiring a field map. The method requires only about two times the total computation time compared to image reconstruction by gridding. It can also be used in combination with a full field map automatic off‐resonance correction method to increase the extent of correction. The method is demonstrated by in vivo coronary artery imaging. Magn Reson Med, 2006. © 2006 Wiley‐Liss, Inc.