A Statistical Robust Approach to Design Parallel Transmit Radiofrequency Excitations in MRI

Figure 4

Cumulative histogram of the ratio , whereby and are the theoretical lower bounds for the effective control’s CV in the pTX (8 degrees of freedom) and the CP (1 degree of freedom) modes. The more “agile” pTX drive mode can adapt to the known control field statistics and thereby allows reducing significantly the lower bound for the CV of the effective control field. A reduction factor of at least 1.5 is obtained for 80% of the voxels of the brain. In some areas, the CV reduction factor reaches a factor of 2 or more.