A Self-Decoupled 32 Channel Receive Array for Human Brain Magnetic Resonance Imaging at 10.5T

TL;DR

This study introduces a novel self-decoupled 32-channel receive array for human brain MRI at 10.5T, demonstrating significant improvements in SNR and parallel imaging performance over 7T systems through experimental comparisons.

Contribution

The paper presents a new self-decoupled 32-channel receive array design for 10.5T MRI, achieving enhanced SNR and parallel imaging capabilities compared to existing 7T arrays.

Findings

10.5T array provides 1.46x central SNR and 2.08x peripheral SNR over 7T.

Significantly higher g-factor performance at 10.5T, enabling better acceleration.

Array performance comparable to a 64-channel 7T receiver.

Abstract

Purpose: Receive array layout, noise mitigation and B0 field strength are crucial contributors to signal-to-noise ratio (SNR) and parallel imaging performance. Here, we investigate SNR and parallel imaging gains at 10.5 Tesla (T) compared to 7T using 32-channel receive arrays at both fields. Methods: A self-decoupled 32-channel receive array for human brain imaging at 10.5T (10.5T-32Rx), consisting of 31 loops and one cloverleaf element, was co-designed and built in tandem with a 16-channel dual-row loop transmitter. Novel receive array design and self-decoupling techniques were implemented. Parallel imaging performance, in terms of SNR and noise amplification (g-factor), of the 10.5T-32Rx was compared to the performance of an industry-standard 32-channel receiver at 7T (7T-32Rx) via experimental phantom measurements. Results: Compared to the 7T-32Rx, the 10.5T-32Rx provided 1.46 times the central SNR and 2.08 times the peripheral SNR. Minimum inverse g-factor value of the 10.5T-32Rx (min(1/g) = 0.56) was 51% higher than that of the 7T-32Rx (min(1/g) = 0.37) with R=4x4 2D acceleration, resulting in significantly enhanced parallel imaging performance at 10.5T compared to 7T. The g-factor values of 10.5T-32Rx were on par with those of a 64-channel receiver at 7T, e.g. 1.8 versus 1.9, respectively, with R=4x4 axial acceleration. Conclusion: Experimental measurements demonstrated effective self-decoupling of the receive array as well as substantial gains in SNR and parallel imaging performance at 10.5T compared to 7T.