Meeting Banner
Abstract #3312

Neural Network-supported Fast Online-Customized (FOCUS) parallel transmit (pTx) pulses for slice-selective, large flip angle excitation

Jürgen Herrler1, Patrick Liebig2, Kurt Majewski3, Rene Gumbrecht2, Dieter Ritter2, Christian Richard Meixner4, Andreas Maier5, Arnd Dörfler1, and Armin Michael Nagel4,6
1Department of Neuroradiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany, 2Siemens Healthcare GmbH, Erlangen, Germany, 3Department of Corporate Technology, Siemens, München, Germany, 4Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany, 5Department of Computer Science, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany, 6Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany


Slice-selective, two-spoke parallel transmit (pTx) pulses for exciting large flip angles can be designed quickly and show robust performance for MRI at 7 Tesla using an 8Tx/32Rx coil. Firstly, clusters of B1+/B0 maps are defined and corresponding pulses are optimized prior to the scan. These serve as initialization for a fast, gradient-descent based online-optimization. For each slice, the best cluster-specific initialization is chosen online via neural networks, which predict their respective spatial distribution of the longitudinal magnetization. This approach outperforms other strategies to initialize the pTx RF pulses such as offline-optimized slab-specific and circularly polarized RF pulses as initializations.

This abstract and the presentation materials are available to members only; a login is required.

Join Here