Study On CT Image Reconstruction Method And Contrast Agent

Computed tomography?CT?has been widely used in medical,industrial,food,national defense,aerospace and other fields as an important non-destruction testing method.As a key technology of CT imaging system,reconstruction algorithm is directly related to the quality of the obtained images in CT imaging system.At present,filtering back projection is widely used as a mainly algotithm in reconstruction methods,and different filtering functions can achieve different quality of reconstruction images.In order to obtain better reconstruction images and internal information of subjects,we analysize the mathmatical foundation of FBP filtering function,also research mathematical expression formation of different filtering functions is influence on images-reconstructed quality.According to this foundation,proposing an optimized filter function to achieve image reconstruction.The optimized filtering function was used,the reconstruction of images under different environment is simulated by computer,the reconstruction effect of optimized filtering function is studied through the present experimental plate.The experimental results illustrated that the optimized filtering function have a better image reconstruction effect than traditional function.In CT clinical application,related contrast agents can be applied for X-ray imaging to achieve diagnosis of diseases.Traditional agents are small molecule,fast degrade,amount of those need to be injected.Moreover,a little poisonious.Thus,to make up the shortcomings of clinical contrast agents,at the same time,owing to consider the problem of singal CT insufficient diagnosis of diseases,combined with the nuclear magnetic resonance imaging?MRI?technology and fluorescence imaging?FI?can achieve accurate diagnosis of diseases.It based on CT application technology,in order to take advantages of nanomaterials,proposesing a novel nano-material contrast agent Ba₄Yb₃F₁₇:Lu³⁺,Gd³⁺which can come true CT and MRI/FI simultaneously.First,the nanomaterial contrast agents Ba₄Yb₃F₁₇:Lu³⁺,Gd³⁺were sythesized by hydrothermal,through different ways to study the physical and chemical properties,then,studying on its applicability in biological vitro evaluation,combining with experiment in vitro and its characterization of the system,and finally,those were applied to biology research.The experimental results show that this kind of contrast agents Ba₄Yb₃F₁₇:Lu³⁺,Gd³⁺have the advantages of the longer blood-cycle,low injection dose than traditional contrast agents,multimodal imaging function,and which can achieve a good imaging effect,it offer an efficient way for accurate diagnosis of diseases.