Comparing short scan CT reconstruction algorithms regarding cone-beam artifact performance

While circular cone-beam computed tomography (CBCT) has numerous advantages in CT scanner design, the image reconstruction from circular cone-beam data is known to be approximate since the data sufficiency condition is not fulfilled. This is an unresolved issue yet and may become a problem if the number of detector rows is further increased in the future. The purpose of this work is to evaluate different CBCT reconstruction algorithms regarding their cone-beam artifact performance. For the comparison the two standard methods Feldkamp and SART are used. Additionally the factorization approach, which is designed for reconstruction with low cone-beam artifacts and a new method for cone-beam artifact reduction (CBAR) based on iterative filtered backprojection reconstruction are used. Among the compared algorithms, the Feldkamp reconstruction has the lowest computational load and shows the worst cone-beam artifacts while the factorization approach shows the best trade-off between cone-beam artifacts and computation time.