Image Reconstruction Algorithm Research With Multi-Slice Helical CT Scanning

With the development of spiral multi-slice CT, medical CT is in transition towards spiral cone-beam CT. Image reconstruction from spiral cone-beam data is practically advantageous, but it is mathematically complicated and technically challenged. So far, few researchers in China have done research in the field.As a part of the national "863" high-tech research subject:16 Slice Image Reconstruction Algorithm Research with Spiral Cone-Beam Scan, the thesis deals with three approximate algorithms, one of which is The Weighted Spiral Image Reconstruction, the conjugate channel interpolation is applied, which improves the image effect, The other two algorithms: Pi-Original and Pi-Slant are based on three dimension backprojection, the conjugate channel interpolation is applied to solve the backprojection loss caused by the computation error. Compared with the traditional FDK algorithm, the two PI algorithms decrease the helical shadow. Furthermore, Iteration method is applied to solve the problem of parse of complicated equation and the two algorithms are simulated perfectly for the first time in China.The thesis makes a summary about the reconstruction algorithm with parallel scan, fan scan and helical scan for the first time in China, with a detailed deduction for all the reconstruction formulas, the simulation experiment results are showed.