This work proposes four optimization strategies for the RF shimming in UHF MRI. The results show a minimum coefficient of variation of B1+ field distribution over the human head = 23%/17%/14% for the 4chTEM, 16chTTT, and 64chTTT respectively. For the maximum over minimum evaluation criteria of the B1+ field distribution, the best values were 6.70/2.92/2.23 for 4chTEM/16chTTT/64chTTT coils. For a fixed mean B1+ field over the human head, the best average SAR values were 2.09/1.28W/kg for the 4chTEM/16chTTT coils respectively. These strategies can be applied to any RF transmit array system, but are most beneficial for highly parallel systems.
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