Fast method for dynamic MR imaging
AssigneeThe Board of Trustees of the Leland Stanford Junior University
InventorsZhi-Pei Liang, Norbert J. Pelc
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Abstract
Generalized series-based image reconstruction as used in dynamic imaging for high-speed imaging with limited k-space coverage for each time frame. Further, in acquiring low resolution data for a plurality of image frames, a full k-space data set is generated for each time frame with the measured low-resolution data and high spatial frequency data generated by the GS model constructed based on the high-resolution image(s). The algorithms of the invention have computational complexity of O(N log N) and arc capable of producing high-resolution dynamic images with a small number of Fourier transform samples.
Claims10
A method of image reconstruction for fast dynamic imaging using a generalized-series (GS) model comprising the steps of:
- a) acquiring data for at least one high resolution reference image, Ir({right arrow over (x)}),
- b) acquiring one or more dynamic k-space data sets, dq({right arrow over (k)}), for one or more image datasets, q, where 1≦q≦Q,
- c) determining an image weighting function w({right arrow over (x)}) based on the reference image(s),
- d) determining a contrast modulation function, C({right arrow over (x)}), for each data frame to absorb dynamic signal variations,
- e) multiplying the weighting function w({right arrow over (x)}) by the contrast modulation function, C({right arrow over (x)}), to obtain an initial estimate of the image for each time point,
- f) using the initial estimate obtained in step e) and phase information from the reference image(s) to estimate a full k-space data set,
- g) replacing estimated k-space data obtained in step e) with the acquired data in step b) at the k-space locations where dq({right arrow over (k)}) is acquired to achieve data consistency in a merged data set, and
- h) Fourier transforming the merged data set obtained in step g) to generate the desired image function.
Dependencies are inferred from the claim text.