1. Department of Biomedicine, Neuroscience and Advanced Diagnostic (Bi.N.D.), University Hospital "Policlinico P. Giaccone", Palermo, Italy
2. Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria
3. Department of Biomedical Sciences and Morphologic and Functional Imaging, University of Messina, Messina, Italy