超导磁共振仪无源匀场测试系统的设计与开发

Design and Development of a Passive ShimmingControl and Measurement System for Superconducting MRI

摘要:

超导磁共振仪作为目前主流的医疗成像设备，在临床诊断和患者检查方面作用突出，其成像质量直接取决于主磁场中心球形成像区域（DSV）的均匀性。匀场技术作为一种实现DSV磁场均匀化的技术就显得尤为重要。针对磁共振成像系统DSV磁场测量的传统方法中探头位置移动不准确、数据记录繁琐、操作过程复杂等缺点，设计了基于Labview的新型DSV磁场测量系统：通过设计Labview控制程序对高斯计进行仪器控制，划分DSV球形表面的测量点，通过调节测量装置来精确移动探头位置，编写串口通信、数据采集程序，完善人机交互界面，实现DSV表面测量点磁场数据的实时采集，无需手动记录，可通过导出数据到TXT文件的方式保存磁场数据至本地。经工程实际应用，操作便捷，实测DSV均匀度为416.0506ppm，通过线性规划算法匀场后均匀度为：16.0383ppm，提升超过96%。

Abstract:

As the current mainstream medical imaging equipment, superconducting magnetic resonance apparatus plays an important role in clinical diagnosis and patient examination. The imaging quality of the superconducting magnetic resonance apparatus directly depends on the uniformity of the central spherical imaging area (DSV) of the main magnetic field. Shimming technology is particularly important as a technology to achieve uniform DSV magnetic field. Aiming at the shortcomings of inaccurate probe position movement, cumbersome data recording and complicated operation process in traditional methods of Magnetic Resonance Imaging System (DSV) magnetic field measurement, a new DSV magnetic field measurement system based on Labview was designed: Gaussmeter instrument control was designed by designing a Labview control program. Divide the measurement points of the spherical surface of DSV, adjust the measurement device to accurately move the position of the probe, compile the serial communication and data acquisition program, improve the human-computer interaction interface, and realize the real-time collection of the magnetic field data of the DSV surface measurement point without manual recording. Exporting data to a TXT file saves the magnetic field data to the local. The actual application of the project, the operation is convenient, the measured DSV uniformity is 416.0506ppm, after the shimming uniformity by the linear programming algorithm: 16.03383ppm, increased by more than 96%.