Pablo Dominguez1, Shinji Naganawa2. 1. Department of Radiology, Clinica Universidad de Navarra, University of Navarre, Avda. Pio XII 36, 31008, Pamplona, Navarre, Spain. 2. Department of Radiology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Shouwa-ku, Nagoya, 466-8550, Japan. naganawa@med.nagoya-u.ac.jp.