1. Department Experimental and Clinical Medicine University “Magna Graecia” of Catanzaro Catanzaro 88100 Italy
2. Division of Imaging & Oncology Department of Radiotherapy University Medical Center Utrecht Heidelberglaan Utrecht The Netherlands
3. Computational Imaging Group for MR Diagnostics & Therapy Center for Image Sciences University Medical Center Utrecht Heidelberglaan Utrecht The Netherlands
4. Division of Biomedical Physics in Radiation Oncology DKFZ German Cancer Research Center Heidelberg Germany
5. Department of Physics and Astronomy Heidelberg University Heidelberg Germany