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Abstract #2462

Non-rigid Motion Correction in 3D Using Autofocusing with Localized Linear Translations

MAGNA25Joseph Y. Cheng1, Marcus T. Alley2, Charles H. Cunningham3, 4, Shreyas S. Vasanawala2, John M. Pauly1, Michael Lustig5

1Electrical Engineering, Stanford University, Stanford, CA, United States; 2Radiology, Stanford University, Stanford, CA, United States; 3Medical Biophysics, University of Toronto, Toronto, Ontario, Canada; 4Imaging Research, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada; 5Electrical Engineering and Computer Science, University of California, Berkeley, CA, United States

MR scans are sensitive to motion effects due to the scan duration. On a sufficiently small spatial-scale, the complex non-rigid motion can be well approximated as simple linear translations. This formulation allows for a practical autofocusing algorithm that locally minimizes a given motion metric -- more specifically, the proposed localized gradient-entropy metric. To reduce the vast search space for an optimal solution, possible motion paths are limited to motion measured from multi-channel Butterfly navigation data. The correction scheme is applied to free-breathing abdominal patient studies. A reduction in artifacts from non-rigid motion is observed.

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