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Fast automatic linear off-resonance correction method for spiral imaging.

Weitian Chen·Craig H Meyer
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Abstract

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.

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AlgorithmsChi-Square DistributionHeartHumansImage Processing, Computer-AssistedMagnetic Resonance ImagingPhantoms, ImagingJournal ArticleResearch Support, Non-U.S. Gov't

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Weitian Chen, Craig H Meyer. 2006. Fast automatic linear off-resonance correction method for spiral imaging.. https://doi.org/10.1002/mrm.20973

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