Reduction of Gradient Acoustic Noise in MRI Using SENSE-EPI.
de Zwart J, van Gelderen P, Kellman P, Duyn J.
A new approach to reduce gradient acoustic noise levels in EPI experiments is
presented. Using multichannel RF receive coils, combined with SENSE data
acquisition and reconstruction, gradient slew-rates in single-shot EPI were
reduced fourfold for rate-2 and ninefold for rate-3 SENSE. Multislice EPI
experiments were performed on three different scanner platforms. With 3.4 mm
in-plane resolution, measuring 6 slices per second (12 slices with 2000 ms TR),
this resulted in average sound pressure level reductions of 11.3 dB(A) and 16.5
dB(A) for rate-2 and rate-3 SENSE, respectively. BOLD fMRI experiments, using
visually paced finger-tapping paradigms, showed no detrimental effect of the
acoustic noise reduction strategy on temporal noise levels and t scores.