Image reconstruction with a source space tree algorithm for Compton CT.

This paper proposes a Compton CT technique which accurately reconstructs the image of the radiation source distribution in the object cross section from the data observed by Compton scattering. The source space tree algorithm (SSTA) is proposed as an image reconstruction method in Compton CT. The method consists of reconstructing the source distribution by summing the weights assigned to the voxels intersecting the surface of a cone determined by the Compton scattering angle. In this process, it is necessary to make a decision about the intersection between the voxels composing the back-projection space and the cone surface. In the conventional method, the spherical region is used in making the decision. This may produce an incorrect judgment of intersection, resulting in an artifact on the image. In the proposed method, a cube is used instead of a sphere. This makes the intersection decision more accurate, resulting in reconstruction of the image without artifacts. The effectiveness of the proposed method is verified by simulations. © 2003 Wiley Periodicals, Inc. Syst Comp Jpn, 34(11): 1–9, 2003; Published online in Wiley InterScience (<URL>www.interscience.wiley.com</URL>). DOI 10.1002/scj.10496 [ABSTRACT FROM AUTHOR]