1. Vein Centre of the Dermatology and Vascular Surgery Clinics, Hospital of Ruhr-University Bochum, St. Maria-Hilf Hospital, Venenzentrum, Bochum, Germany
2. Medical Office Specialized on Phlebology, Hamburg, Germany
3. Department of Dermatology, Venereology, and Allergology, University Hospital Erlangen, Erlangen, Germany
4. Medical Office Specialized on General Surgery, Helbra, Germany
5. Department of Vascular Surgery and Vascular Medicine, Schwarzwald-Baar Hospital Villingen-Schwenningen, Villingen-Schwenningen, Germany
6. Medical Affairs and Clinical Research Department, URGO GmbH, Sulzbach, Germany
7. Department of Dermatology, Venereology and Allergology, University Hospital Essen, Essen, Germany