颅内深层激励磁感应检测系统设计

Design of magnetic induction detection system for deep intracranial excitation

目的:研究采用双8字线圈作为磁感应检测系统的激励端以提升颅脑模型激励深度的可行性。方法:基于5层颅脑模型,分别建立以双8字线圈和圆形线圈作为激励端的仿真检测系统,比较2种仿真系统在颅脑模型水平方向与竖直方向上的磁场强度及对不同电导率病变体的检测结果;搭建双8字线圈与圆形线圈硬件实验系统,使用不同电导率的NaCl溶液作为被测物,进行相位差检测实验以评价系统性能。结果:系统仿真计算结果表明,双8字线圈磁感应检测系统相比于圆形线圈磁感应检测系统,在同一检测点处产生的磁场强度更大、不同电导率病变体检测后系统得到的相位差值更大;NaCl溶液实测结果表明,双8字线圈磁感应检测系统得到的相位差值更高。结论:设计的双8字线圈磁感应检测系统可以从整体上提升系统的激励、检测深度,为颅脑深层组织成像提供了研究思路。

Objective To study the feasibility of using double 8-character coil as the excitation end of the magnetic induction detection system to enhance the excitation depth of the craniocerebral model.Methods Based on a five-layer craniocerebral model,two simulation detection systems respectively with double 8-shaped coil and circular coil as the excitation end were established.The two simulation systems were compared for the magnetic field intensities at horizontal and vertical directions of cerebrocranial model as well as the diagnoses of lesions with different conductivities;two hardware experiment systems respectively with double-8 coil and circular coil were established,and NaCl solution with different conductivities was used as the tested object to evaluate the performances of the systems.Results The simulation results showed that the simulation detection system with double 8-shaped coil had higher magnetic field intensity than the one with circular coil at the same point,and higher phase difference than the other after detecting lesions with different conductivities;the experiments with NaCl solution proved that the simulation detection system with double 8-shaped coil gained higher phase difference when compared with the other system.Conclusion The designed double 8-shaped coil magnetic induction detection system enhances the overall excitation-detection depth of the system,and provides a research idea for deep brain tissue imaging.