1. Department of Dermatology, Pellegrin Children’s Hospital, Bordeaux, France;
2. Department of Dermatology, Universitat Autònoma de Barcelona and Hospital de la Santa Creu i Sant Pau, Barcelona, Spain;
3. Department of Pediatric Dermatology, University Children’s Hospital Zurich, Zurich, Switzerland;
4. Center for Vascular Anomalies, Division of Plastic Surgery, Cliniques Universitaires St Luc, Brussels, Belgium;
5. Pediatric Dermatology Unit, Bambino Gesù Children’s Hospital, IRCCS, Rome, Italy;
6. Expertise Center for Hemangioma and Vascular Malformations, Department of Dermatology, Radboud University Medical Center, Nijmegen, Netherlands;
7. Center of Pediatrics and Adolescent Medicine, Medical Center–University Freiburg, Freiburg, Germany; and
8. Centre for Laser and Vascular Anomalies, Department of Dermatology, Skåne University Hospital, Malmö, Sweden