A self‐decoupled 32‐channel receive array for human‐brain MRI at 10.5 T. Issue 3 (29th March 2021)

• Record Type: Journal Article
• Authors: Tavaf, Nader; Lagore, Russell L.; Jungst, Steve; Gunamony, Shajan; Radder, Jerahmie; Grant, Andrea; Moeller, Steen; Auerbach, Edward; Ugurbil, Kamil; Adriany, Gregor; Van de Moortele, Pierre‐Francois
• Is Part Of: Magnetic resonance in medicine. Volume 86:Issue 3(2021)
• Page Start: 1759
• Page End: 1772
• Publication Date: 2021-03-29
• Subjects: noise correlation -- parallel imaging -- receive array -- RF coils -- self‐decoupling -- ultrahigh‐field MRI; Nuclear magnetic resonance -- Periodicals; Electron paramagnetic resonance -- Periodicals; 616.07548
• DOI: 10.1002/mrm.28788
• Languages: English
• ISSNs: 0740-3194

Abstract

Abstract : Purpose: Receive array layout, noise mitigation, and B0 field strength are crucial contributors to SNR and parallel‐imaging performance. Here, we investigate SNR and parallel‐imaging gains at 10.5 T compared with 7 T using 32‐channel receive arrays at both fields. Methods: A self‐decoupled 32‐channel receive array for human brain imaging at 10.5 T (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 with the performance of an industry‐standard 32‐channel receiver at 7 T (7T‐32Rx) through experimental phantom measurements. Results: Compared with 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 = 4 × 4 2D acceleration, resulting in significantly enhanced parallel‐imaging performance at 10.5 T compared with 7 T. The g‐factor values of 10.5 T‐32 Rx were on par with those of a 64‐channel receiver at 7 T (eg, 1.8 vs 1.9, respectively, with R = 4 × 4 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 10.5 T compared with 7 T.