An 8-channel receive array for improved P MRSI of the whole brain at 3T.

PURPOSE

To demonstrate a H/ P whole human brain volume coil configuration for 3 Tesla with separate P transmit and receive components that maintains H MRS performance and delivers optimal P MRSI with H decoupling.

METHODS

We developed an 8-channel P receive array coil covering the head to be used as an insert for a commercial double-tuned H/ P birdcage transmit-receive coil. This retains the possibility of using low-power rectangular pulses for H-decoupled 3D P MRSI (nominal resolution 17.6 cm ; acquisition duration 13 min) but increases the SNR with the receive sensitivity of P surface coils. The performance of the combined coil setup was evaluated by measuring H and P SNR with and without the P receive array and by assessing the effect of the receive array on the transmit efficiencies of the birdcage coil.

RESULTS

Compared to the birdcage coil alone, the P insert in combination with the birdcage achieved an average P SNR gain of 1.4 ± 0.4 in a center partition of the brain. The insert did not cause losses in H MRS performance and transmit efficiency, whereas for P approximately 20% more power was needed to achieve the same γB1.

CONCLUSION

The new coil configuration allows H MRSI and optimal H-decoupled 3D P MRSI, with increased SNR of the human brain without patient repositioning, for clinical and research purposes at 3 Tesla.