Feldkamp-type image reconstruction from equiangular data.

The cone-beam approach for image reconstruction attracts an increasing attention in various applications, especially medical imaging. Previously, the traditional practical cone-beam reconstruction method, the Feldkamp algorithm, was generalized into the case of spiral/helical scanning loci with equispatial cone-beam projection data. In this paper, we formulated the generalized Feldkamp algorithm in the case of equiangular cone-beam projection data, and performed numerical simulation to evaluate the image quality. Because medical multi-slice/cone-beam CT scanners typically use equiangular projection data, our new formula may be useful in this area as a framework for further refinement and a benchmark for comparison.