Author/Authors :
Nan, Jiaofen School of Computer and Communication Engineering - Zhengzhou University of Light Industry - Zhengzhou, China , Zong, Nannan School of Computer and Communication Engineering - Zhengzhou University of Light Industry - Zhengzhou, China , Chen, Qiqiang School of Computer and Communication Engineering - Zhengzhou University of Light Industry - Zhengzhou, China , Zhang, Liangliang School of Computer and Communication Engineering - Zhengzhou University of Light Industry - Zhengzhou, China , Zheng, Qian School of Computer and Communication Engineering - Zhengzhou University of Light Industry - Zhengzhou, China , Xia, Yongquan School of Computer and Communication Engineering - Zhengzhou University of Light Industry - Zhengzhou, China
Abstract :
The acoustic problem of the split gradient coil is one challenge in a Magnetic Resonance Imaging and Linear Accelerator (MRILINAC) 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.
