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Abstract #3466

Wave-Number Imaging at 7T: Increasing Accuracy of EPT at High Field Strengths

Astrid L.H.M.W. van Lier1, Ulrich Katscher2, Alexander Raaijmakers1, Cornelis A.T. van den Berg1

1Radiotherapy, UMC Utrecht, Utrecht, Netherlands; 2Philips Research Europe, Hamburg, Germany

Recently, it was shown that dielectric properties can be mapped using MRI. Electrical properties mapping relies on measurements of the B1+ amplitude and phase. This phase, however, cannot be measured directly; therefore, the assumption that the transceive phase is twice the B1+ phase is used in a transceiver setup. This assumption is acceptable at low field strengths, however, leads to significant reconstruction errors at 7T. Here we show, that the wave-number (|k|) is less susceptible to these errors, and can be mapped more reliably than the permittivity and conductivity at 7T.

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Keywords

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