Evaluation of a full dynamic density adapted radial 4D-pcASL angiography sequence exploiting B1+-shimming and ramped SPINS excitation at 7T
Christian R. Meixner1, Max Müller1, Sebastian Schmitter2,3, Jürgen Herrler4, Arnd Dörfler4, Michael Uder1, and Armin M. Nagel1,3
1Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander- Universität Erlangen-Nürnberg (FAU), Erlangen, Germany, 2Physikalisch-Technische Bundesanstalt (PTB), Braunschweig und Berlin, Germany, 3Division of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany, 4Department of Neuroradiology, University Hospital Erlangen, Friedrich-Alexander- Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
In this work, a whole-brain 4D-pcASL angiography sequence exploiting a radial density-adapted gradient echo readout with golden angle sampling was implemented and evaluated on a 7T system. Various parallel transmission (pTx) strategies were compared to the standard circularly polarized mode: To counteract low transmit efficiency in the labeling, B1+-shimming was used in combination with a full spiral-nonselective pTx-optimized readout train. Further, constant flip angle pTx-excitations in the readout were compared to pTx-pulses that were ramped from 3.5° to 6.5° using a linear scaling factor. This ramped readout strategy outperforms constant flip angles and reveals more of the vascular tree
This abstract and the presentation materials are available to members only;
a login is required.