22 March 2010 A new approach to limited angle tomography using the compressed sensing framework
Author Affiliations +
The limited angle problem is a well-known problem in computed tomography. It is caused by missing data over a certain angle interval, which make an inverse Radon transform impossible. In daily routine this problem can arise for example in tomosynthesis, C-arm CT or dental CT. In the last years there has been a big development in the field of compressed sensing algorithms in computed tomography, which deal very good with incomplete data. The most popular way is to integrate a minimal total variation norm in form of a cost function into the iteration process. To find an exact solution of such a constrained minimization problem, computationally very demanding higher order algorithms should be used. Due to the non perfect sparsity of the total variation representation, reconstructions often show the so called staircase effect. The method proposed here uses the solutions of the iteration process as an estimation for the missing angle data. Compared to a pure compressed sensing-based algorithm we reached much better results within the same number of iterations and could eliminate the staircase effect. The algorithm is evaluated using measured clinical datasets.
© (2010) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Ludwig Ritschl, Ludwig Ritschl, Frank Bergner, Frank Bergner, Marc Kachelriess, Marc Kachelriess, "A new approach to limited angle tomography using the compressed sensing framework", Proc. SPIE 7622, Medical Imaging 2010: Physics of Medical Imaging, 76222H (22 March 2010); doi: 10.1117/12.844303; https://doi.org/10.1117/12.844303

Back to Top