Cone beam backprojection reconstruction from sources distributed on a spherical surface

摘要

One of the recent efforts in development of cone-beam CT is aimed at the construction of a volumetric CT apparatus with distributed X-ray sources. This new concept in 3D CT requires a CT reconstruction algorithm designed for X-ray foci uniformly distributed on a surface rather than on a curve. To research the properties of such algorithm an exact reconstruction formula is derived for a continuous distribution of sources on a surface of a sphere. The algorithm is implemented vising finite number of focal spots for simulated phantom projection data. High resolution images were obtained for 100-400 focal spots for both noiseless and noisy input. The results exhibit a potential for CT image reconstruction from highly undersampled projection data.