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arXiv · 2412.12711

Complex extension of optical flow and its practical evaluation for undersampled dynamic MRI

Matthias J. Ehrhardt·Marco Mauritz
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Abstract

Reconstructing high-quality images from undersampled dynamic MRI data is a challenging task and important for the success of this imaging modality. To remedy the naturally occurring artifacts due to measurement undersampling, one can incorporate a motion model into the reconstruction so that information can propagate across time frames. Current models for MRI imaging are using the optical flow equation. However, they are based on real-valued images. Here, we generalise the optical flow equation to complex-valued images and demonstrate, based on two real cardiac MRI datasets, that the new model is capable of improving image quality.

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Matthias J. Ehrhardt, Marco Mauritz. 2024-12-17. Complex extension of optical flow and its practical evaluation for undersampled dynamic MRI. https://doi.org/10.3934/ammc.2025005

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