1. Clinic for Neurology; Hannover Medical School; Hannover Germany
2. Clinic for Gastroenterology, Hepatology and Endocrinology; Hannover Medical School; Hannover Germany
3. Division of Gastroenterology, Hepatology & Nutrition; East Carolina University; Greenville North Carolina
4. Institute for Diagnostic and Interventional Neuroradiology; Hannover Medical School; Hannover Germany