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Abstract #2679

Multiplexed EPI at 9.4T with PSF-Based Distortion Correction

Seong Dae Yun1, Nadim Jon Shah1, 2

1Institute of Neuroscience and Medicine - 4, Forschungszentrum Jlich, Jlich, Germany; 2JARA - Faculty of Medicine, RWTH Aachen University, Aachen, Germany

The relatively high imaging speed of EPI has led to its widespread use in dynamic MRI studies. For even faster acquisition of multiple slices in EPI, M-EPI (Multiplexed EPI) method has been recently presented (Feinberg et al.). However, because of the intrinsically low bandwidth in the phase encode direction, EPI-based methods are highly sensitive to field inhomogeneities, which results in potentially severe geometric distortions. This problem becomes more challenging at ultra-high fields such as 9.4T. The present work verifies i) the use of M-EPI at 9.4T and ii) demonstrates the application of the PSF (Point Spread Function)-based correction method to the M-EPI images to remove the geometric distortions.

Keywords

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