A Structure Design Method for Reduction of MRI Acoustic Noise.

A Structure Design Method for Reduction of MRI Acoustic Noise.
Comput Math Methods Med. 2017;2017:6253428
Authors: Nan J, Zong N, Chen Q, Zhang L, Zheng Q, Xia Y
Abstract
The acoustic problem of the split gradient coil is one challenge in a Magnetic Resonance Imaging and Linear Accelerator (MRI-LINAC) system. In this paper, we aimed to develop a scheme to reduce the acoustic noise of the split gradient coil. First, a split gradient assembly with an asymmetric configuration was designed to avoid vibration in same resonant modes for the two assembly cylinders. Next, the outer ends of the split main magnet were constructed using horn structures, which can distribute the acoustic field away from patient region. Finally, a finite element method (FEM) was used to quantitatively evaluate the effectiveness of the above acoustic noise reduction scheme. Simulation results found that the noise could be maximally reduced by 6.9 dB and 5.6 dB inside and outside the central gap of the split MRI system, respectively, by increasing the length of one gradient assembly cylinder by 20 cm. The optimized horn length was observed to be 55 cm, which could reduce noise by up to 7.4 dB and 5.4 dB inside and outside the central gap, respectively. The proposed design could effectively reduce the acoustic noise without any influence on the application of other noise reduction methods.
PMID: 29234459 [PubMed - in process]

Source: Computational and Mathematical Methods in Medicine - December 15, 2017 Category: Statistics Tags: Comput Math Methods Med Source Type: research