Start of funding 01.01.2011

Combined Scatter and Beam Hardening Correction for Computed Tomography

Prof. Dr. Marc Kachelrieß
Friedrich-Alexander-University of Erlangen-Nuremberg
Lehrstuhl für Medizinische Physik

Prof. Dr. Norbert Pelc
Stanford University
Radiological Sciences Laboratory



Computed tomography (CT) is one of the most important and useful diagnostic tools in medicine today. However the quality of three-dimensional data in CT scans is impaired by the physical effects of beam hardening and scattered radiation. The objective of this project is to simultaneously address both effects, since individually they cannot be reduced efficiently. First a modulation of the primary signal is performed. After an algorithmical spectral correction the signal provides the information necessary for a separation and quantification of both effects. This allows a reduction of the image artifacts which are caused by beam hardening and scattered radiation. As a result diagnostic benefit of CT improves. Hereby the welfare of the patient is increased.

Final report:
Computed Tomography (CT) is one of the most important and useful diagnostic tools in medicine today. However the quality of three-dimensional data in CT scans is impaired by the physical effects of beam hardening and scattered radiation. A correction method which simultaneously addresses the scatter as well as the beam hardening effects was developed within this project. With this method the image quality was significantly increased by the reduction of the corresponding artifacts. To enable this method for spatial varying spectra correction was developed which was already also transferred to other applications. Furthermore a second research project was initiated and performed which raised due to the direct contacts of the scientist of the different institutions.
Besides this the outcome of this project is one patent application, one journal publication and four contributions to scientific conferences.