Diagnostic Criteria for PPG
Cuff Position Mean VRT Location of Venous Incompetence

No tourniquet

≥ 20 sec None
  < 20 sec Incompetence present (*further testing needed to determine if supercficial or deep)
Distal thigh tourniquet ≥ 20 sec Great saphenous
  < 20 sec Deep and superficial venous system
Proximal calf tourniquet ≥ 20 sec Small saphenous
  ≥ 20 sec Deep and superficial venous system

'Size, G (2013). Inside Ultrasound Vascular Reference Guide. Inside Ultrasound, Incorporated'Purchase Now