EnPiT: A reconstruction algorithm for helical CT

A reconstruction algorithm for helical CT using a 3-Pi acquisition is presented. Here we show, how we can deal with data obtained by an n-Pi acquisition, where n can be any positive odd integer. The method, viz. EnPiT, is a filtered back-projection algorithm and is based on the results obtained for n=1 by A. Katsevich. For an n-Pi acquisition, we have to ensure that all Radon-planes receive the correct weights. Therefore, n different sets of filter-lines are needed. Nevertheless, the presented sets of filter-lines allow for an efficient implementation, such that the computational complexity increases only slowly with n. Simulation results demonstrate that the algorithm works satisfactorily. The reconstructed images exhibit excellent quality