DUPLEX SCAN SURVEILLANCE OF INFRA-INGUINAL BYPASS GRAFTS

Duplex scanning, which allows ultrasonic imaging of blood vessels and coincident Doppler qualification of the velocity of blood flow within those vessels, has been developed and refined over the past 10–15 years. Although operator‐dependent, vascular surgeons recognize it as one of the most significant recent contributions to the everyday practice of modern vascular surgery when performed by experienced personnel. For example, it is now accepted as the investigation of choice for the non‐invasive diagnosis of carotid bifurcation disease with an increasing number of surgeons avoiding cerebral angiography prior to carotid endarterectomy. It has almost completely superseded venography as the investigation of choice for suspected deep venous thrombosis. Its application to surveillance following arterial reconstructions is logical, particularly for those placed in the leg (femoro‐popliteal/crural bypass) and even more particularly for those bypasses lying in the subcutaneous plane (in situ saphenous vein).