1. Department of Computer Science, University of Freiburg, Freiburg, Germany
2. Department of Diagnostic and Interventional Radiology, Lausanne University Hospital, and University of Lausanne, Lausanne, Switzerland
3. Department of Rheumatology, University Hospital Utrecht, Utrecht, The Netherlands
4. Department of Rheumatology, Lausanne University Hospital, and University of Lausanne, Lausanne, Switzerland