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Abstract #2216

B1+ Inhomogeneity Compensation for RF Refocusing Pulses in Spatially Selective Excitation (SSE) at 7T

Tomasz Dawid Lindel1, 2, Andre Kuehne1, 2, Patrick Waxmann1, 2, Frank Seifert1, 2, Thoralf Niendorf2, Bernd Ittermann1, 2

1Medical Metrology, Physikalisch-Technische Bundesanstalt (PTB), Abbestr. 2-12, 10587 Berlin, Germany; 2Max Delbrck Center for Molecular Medicine (MDC), Berlin Ultra-High Field Facility (BUFF), Berlin, Germany

For brain imaging two-dimensional spatially selective excitation using parallel transmission (pTx) is a well-established technique these days. The missing selectivity along the third spatial dimension is a severe limitation, however. To overcome this we combined 2D-SSE with a conventional slice selective refocusing pulse for phantom and in vivo imaging at 7T. Initially, this resulted in severe signal inhomogeneities due to the spatially non-uniform refocusing at the ultrahigh field. Using RF shimmed refocusing pulses combined with adapted pTx pulses the problem could be resolved.

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Keywords

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