Artifact analysis of approximate helical cone-beam CT reconstruction algorithms

Th. Köhler, R. Proksa, C. Bontus, M. Grass, J. Timmer
2001 Medical Physics (Lancaster)  
In this paper, four approximate cone-beam CT reconstruction algorithms are compared: Advanced single slice rebinning ͑ASSR͒ as a representative of algorithms employing a two dimensional approximation, PI, PI-SLANT, and 3-PI which all use a proper three dimensional back-projection. A detailed analysis of the image artifacts produced by these techniques shows that aliasing in the z-direction is the predominant source of artifacts for a 16-row scanner with 1.25 mm nominal slice thickness. For a
more » ... ector with isotropic resolution of 0.5 mm, we found that ASSR and PI produce different kinds of artifacts which are almost at the same level, while PI-SLANT produces none of these artifacts. It is shown that the use of redundant data in the 3-PI method suppresses aliasing artifacts efficiently for both scanners.
doi:10.1118/1.1413518 pmid:11831573 fatcat:7nbopw4z4rbuxpadrlcd2kg5d4