Relative B1+ Mapping Directly from K-Space for Rapid Multi-Transmit Calibration

Francesco Padormo¹, Shaihan J. Malik¹, Jo V. Hajnal¹

We present a method of obtaining relative multi-channel B1+ information directly from k-space measurements. This approach, which is based on ideas from the SPIRIT technique, is fast, low in SAR and produces maps free of anatomy and noise. The method can also extract full receive coil profiles form the same data. We demonstrate that this technique is capable of full 3D calibration of a whole body 8 channel transmit RF system in 14s plus the time to acquire a single channel B1+ map. Up to 8 receiver channels can be calibrated using the same processing with no further data acquisition.