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Hokkaido University Collection of Scholarly and Academic Papers >
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Gradient Coil Design Method Specifically for Permanent-Magnet-Type Low Field Portable MRI Brain Scanner
| Title: | Gradient Coil Design Method Specifically for Permanent-Magnet-Type Low Field Portable MRI Brain Scanner |
| Authors: | Kong, Xiaohan Browse this author | | Xu, Zheng Browse this author | | Shen, Sheng Browse this author | | Wu, Jiamin Browse this author | | He, Yucheng Browse this author | | Xuan, Liang Browse this author | | Igarashi, Hajime Browse this author →KAKEN DB |
| Keywords: | Brain imaging | | inverse problems | | magnetic resonance imaging (MRI) | | medical diagnosis | | optimization methods |
| Issue Date: | 2-Dec-2022 |
| Publisher: | IEEE (Institute of Electrical and Electronics Engineers) |
| Journal Title: | IEEE transactions on instrumentation and measurement |
| Volume: | 72 |
| Start Page: | 4000512 |
| Publisher DOI: | 10.1109/TIM.2022.3225042 |
| Abstract: | Ferromagnetic structures, particularly the anti-eddy plate, in a bi-planar permanent-magnet-type low-field (0.05 T) magnetic resonance imaging (MRI) brain scanner can distort the gradient field in the target region. This study aims to provide a new gradient coil design method that reduces ferromagnetic influences on gradient field linearity. Thus, a simplified model of electromagnetic (EM) structures of the permanent-magnet-type MRI scanners was established. By using precise analytical proof, the anti-eddy plate was reduced to a homogeneous magnetic plate. The overall effects of the EM structures, which can be represented by bi-planar magnetic plates, were evaluated. In sequence, the image magnetic dipole was first introduced to show the effects of anti-eddy plates were added to the conventional equivalent magnetic dipole (EMD) approach. A novel equivalent image magnetic dipole (EIMD) method was proposed to build the gradient coil pattern. The effect of ferromagnetic materials was predicted throughout the gradient coil design phase using the proposed method, and a high-linear gradient field was generated under real working conditions. The computational and experimental results showed that the gradient coil was linear when ferromagnetic structures were present. The effectiveness of the proposed method was demonstrated by comparing T1-weighted images of the conventional method to those of the proposed method. The proposed method reduced image distortion caused by nearby EM structures in bi-planar permanent-magnet-type low-field MRI systems and provided an effective and concise solution for gradient coil designs. |
| Rights: | © 2022 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. |
| Type: | article (author version) |
| URI: | http://hdl.handle.net/2115/88598 |
| Appears in Collections: | 情報科学院・情報科学研究院 (Graduate School of Information Science and Technology / Faculty of Information Science and Technology) > 雑誌発表論文等 (Peer-reviewed Journal Articles, etc)
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Submitter: 孔 暁涵
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