1. Department of Neurology; Basildon and Thurrock University Hospitals; Essex UK
2. Department of Neurology; Royal London Hospital; London UK
3. Department of Neurology and Division of Neuroradiology; University Hospital Basel; Basel Switzerland
4. Department of Neurology; University of Miami; Miami FL USA
5. Department of Neurology; University of Munich Hospital - Großhadern; Munich Germany
6. Department of Neurology; University of California, San Francisco; San Francisco CA USA