A 15-channel receive array and 16 channel detunable transmit coil for human brain imaging at 9.4 T

The radio frequency (RF) magnetic field (B1) distribution becomes more complex in MR experiments employing higher static magnetic field (B0) due to shorter wavelength in tissue. The B1 + inhomogeneities from a predefined volume of interest is reduced by influencing the amplitude and phase of the transmit current on a transceiver array coil [1, 2]. Significant gains in SNR was achieved at 7T using 32 channel receive arrays assembled on close fitting formers [3, 4]. In this study, we combine the benefits of these two methods for human brain MRI at 9.4T (400MHz). Our imaging setup consists of a 15-element receive array together with a 16-element actively detunable transmit array and hence the additional flexibility to employ RF shimming methods