Optimization of the Receive Performance of a Tight-Fit Transceiver Phased Array for Human Brain Imaging at 9.4T

Tight-fit ultra-high field (UHF) (>7T) surface loop transceiver (TxRx)-phased arrays improve transmit (Tx) efficiency in comparison to Tx-only arrays built larger to accommodate for receive (Rx)-only array inserts. However, the number of elements in TxRx-arrays is restricted by the number of available RF Tx-channels (commonly 8 or 16), which limits the Rx-performance. A prototype of a 16-element array, which consists of 8 TxRx-surface loops circumscribing a head and 8 additional “vertical” Rx-only loops positioned in the center of each TxRx-loop perpendicularly, was constructed. This addition improves the Rx-performance substantially and has a minimal effect on both the Tx-efficiency and maximal local SAR