TOF Angiography in the Human Brain at 7T using 3D Parallel Excitation: Initial Results

Sebastian Schmitter¹, Xiaoping Wu¹, Edward J. Auerbach¹, Michael Hamm², Josef Pfeuffer³, Kamil Ugurbil¹, Pierre-Francois Van De Moortele¹

One of the main challenges in ultra-high-field imaging is the spatial inhomogeneity of transmit B1. In cerebral time-of-flight (TOF) angiography this inhomogeneity results in spatially varying background suppression and thus suboptimal contrast. Parallel transmission (pTX) proved to generate homogeneous excitation by using independent RF waveforms on multiple transmit channels. So far, however, pTX methods have not been used at a large scale in clinical applications, and it remains to be demonstrated that this approach provides reliable results in clinical MR protocols. In this report we demonstrate the successful implementation of Spoke 3D RF pulses in multi-slab TOF angiography at 7T.