1. Division of Cardiovascular Medicine, University of California, Davis Medical Center, Sacramento, CA, USA
2. Lafayette Regional Vein & Laser Center, Lafayette, IN, USA
3. Lake Washington Vascular, Bellevue, WA, USA
4. Connecticut Image Guided Surgery, Fairfield, CT, USA
5. Department of Surgery, New York University Vein Center, New York, NY, USA
6. Vascular Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA