Research on G-arm CT reconstruction algorithm

CT image reconstruction requires certain requirements for projection data. When the projection data is complete, analytical algorithms (such as filtered back-projection algorithm, FBP) or iterative algorithms (ART) can be used for reconstruction. However, in the actual process of obtaining projection, due to limitations such as the geometric position of machine scanning, the structure of the scanning object, and the reasonable and lowest possible radiation dose, the system is difficult to obtain complete projection data, resulting in sparse projection reconstruction or limited angle projection reconstruction problems. This paper proposes a deconvolution iterative algorithm based on direct backprojection for the limited angle reconstruction problem of G-arm CT, and uses the newly proposed reconstruction algorithm combined with L0-GIF to simulate the reconstruction of limited angle projection data. By changing the missing angle, the reconstruction effect under different missing angles was studied. The experimental results showed that our algorithm can achieve good reconstruction quality below a missing angle of 100.