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Abstract #2060

T2*-Weighted Echo-Planar Imaging of Inner Fields-Of-View Using 2D-Selective RF Excitations

Jrgen Finsterbusch1, 2

1Department of Systems Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; 2Neuroimage Nord, University Medical Centers Hamburg-Kiel-Lbeck, Hamburg-Kiel-Lbeck, Germany

With spatially 2D-selective RF excitations rectangular profiles can be excited which can be used to acquire inner fields-of-view without phase-encoding aliasing. Thus, geometric distortions in echo-planar imaging that are caused by magnetic field and susceptibility inhomogeneities, can be reduced for small target regions. In the present study, two approaches are investigated that either involve a FID sequence or a spin-echo-based acquisitions with an echo train shift. The feasibility of both approaches to acquire high-resolution T2*-weighted echo-planar images of inner fields-of-view with minimum distortions is shown. Furthermore, their applicability to functional neuroimaging is demonstrated.

Keywords

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