2D Compensating RF Pulse with Uniform Image Contrast in Combination with an Internal Transceiver at 7T.

Irene M.L. van Kalleveen¹, Hugo Kroeze¹, Alessandro Sbrizzi¹, Vincent Oltman Boer², Reerink Onne¹, Marielle E.P. Philippens¹, Cornelis A.T. van den Berg¹, Peter R. Luijten¹, Dennis W.J. Klomp¹

In high field clinical MRI the B1 field is limited and inhomogeneous, while RF power deposition is high. The use of local antennas at 7T can be beneficial to image for example the rectal wall. However the B1 inhomogeneity becomes even more challenging when using internal transceivers. To compensate for their radial B1 inhomogeneity, we designed a 2D compensating RF pulse. In combination with two harmonic gradients the RF pulse provides a uniform flip angle in two dimensions as demonstrated by 3D FFE in the human rectum.