1. Dermatology Department CHU Caen Université Caen Normandie CHU Caen Côte nacre 14033 Caen Cedex, France
2. Pediatric Dermatology, Hospital Sant Joan de Deu, Barcelona, Spain; VASCERN VASCA European Reference Centre
3. Center for Vascular Anomalies, Division of Plastic Surgery, University Clinics Saint-Luc, University of Louvain, Brussels, Belgium; VASCERN VASCA European Reference Centre
4. Dermatology Unit and Genodermatosis Unit, Genetics and Rare Diseases Research Division, Bambino Gesù Children’s Hospital, IRCCS, Piazza Sant’Onofrio 4, 00165, Rome, Italy; VASCERN VASCA European Reference Centre
5. Paediatric Dermatology, Children’s Health Ireland;Clinical Medicine, Trinity College Dublin, Ireland; VASCERN VASCA European Reference Centre
6. Department of Paediatric and Adolescent Surgery, Medical University of Graz, Graz, Austria; VASCERN VASCA European Reference Centre
7. Department of Plastic and Craniofacial Surgery Karolinska University Hospital Stockholm, Stockholm, Sweden; VASCERN VASCA European Reference Centre
8. Department of Pediatric Surgery, Children’s Hospital, University of Helsinki and Helsinki University Hospital, Helsinki, Finland; VASCERN VASCA European Reference Centre
9. Division of Pediatric Hematology and Oncology, Department of Pediatrics and Adolescent Medicine, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany; VASCERN VASCA European Reference Centre
10. Division of Pediatric Hematology and Oncology, Department of Pediatrics, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
11. Department of Pediatric Surgery, HUSRare Disease Center, Helsinki University Hospital and University of Helsinki, Helsinki, Finland; VASCERN VASCA European Reference Centre
12. Hevas, Patient Organisation for Vascular Anomalies, Nijkerk, the Netherlands
13. Department of Dermatology, Radboudumc Expertise Center for Haemangiomas and Congenital Vascular Malformations Nijmegen (Hecovan), Radboud University Medical Center, Nijmegen, the Netherlands; VASCERN VASCA European Reference Centre
14. Department of Radiology, Radboudumc Expertise Center for Haemangiomas and Congenital Vascular Malformations Nijmegen (Hecovan), Radboud University Medical Center, Nijmegen, the Netherlands; VASCERN VASCA European Reference Centre
15. Human Molecular Genetics, de Duve Institute, University of Louvain, Brussels, Belgium