- Subjects with venous incompetence as defined by reflux longer than 1,0 second in at least one of the following sites: groin [femoral vein, junction of GSV], mid thigh medial [GSV], hollow of the knee [popliteal vein, junction of SSV], mid calf [SSV] in the standing position, measured by Doppler, preferably by duplex within the last 12 month without following active treatment of venous reflux.