A cone-beam tomography algorithm for orthogonal circle-and-line orbit

A cone-beam algorithm which provides a practical implementation of B D Smith's cone-beam inversion formula is presented for a cone-beam vertex orbit consisting of a circle and an orthogonal line. This geometry is easy to implement in a SPECT system, and it satisfies the cone-beam data sufficiency condition. The proposed algorithm is in the form of a convolution-back projection, and requires a pre-filtering procedure. Computer simulations show a reduction of the artifacts that are found with the Feldkamp algorithm where the cone-beam vertex orbit is a circle. (author)