Microwave Imaging Method And Experimental Reserch Of Intracranial Heterogeneity Detection

Intracranial hemorrhage is one of the diseases with the highest death and disability rate in the world.As stroke occurs rapidly,rapid and accurate diagnosis and detection is critically important to prevent the deterioration of the disease and treat patients.At recently,the United States and western developed countries are vying with each other to develop a variety of basic research touched on medical imaging to be applied to the detection of cerebral hemorrhage.One of the key research directions is how to use microwave technology for rapid imaging detection of intracranial heterogeneity.Intracranial heterogeneous microwave detection technology has the characteristics of portability,low radiation(comparing to X-ray),fast detection(comparing to CT,MRI and PET imaging)and penetration strength to skull(comparing to ultrasonic imaging).In recent years,it has received great attention in the fields of bioelectromagnetics,imaging medicine and so on.In electromagnetic scattering,the coupling between intracranial heterogeneity and normal tissue is serious,and the scattering of intracranial heterogeneity is weak,which has become the main obstacle of microwave brain imaging in the development direction of high-performance imaging(high accuracy,high contrast and high resolution).In order to solve the above technical obstacles,this paper mainly focuses on four aspects: the modeling of microwave electromagnetic characteristics of real human brain tissue and the microwave scattering characteristics of intracranial heterogeneous,microwave confocal imaging processing methods,vortex electromagnetic wave high resolution imaging and intracranial heterogeneous detection experiments.In this paper,a method for estimating the equivalent permittivity of intracranial tissue is proposed,and the microwave confocal imaging algorithm based on radar imaging is improved,and then a confocal imaging algorithm based on particle swarm optimization is proposed.It is further verified that the strong scattering effect of vortex electromagnetic waves in the real human brain,and the energy local enhancement is carried out by using the phase characteristics of vortex wave,on the basis of which multi-mode synthetic vortex wave imaging is proposed.Finally,an adjustable microwave imaging experimental device is designed to verify the feasibility of the work.The aforementioned research and results have built a solid foundation for the follow-up work in this direction.