Impact of duplex scanning on vascular surgical practice.

This review outlines the development of duplex scanning over the past 15 years and its value not only in vascular medicine and surgery but also in the field of transplantation and obstetrics. It is now the first line of investigation of patients with symptomatic carotid bifurcation disease and those with clinically suspected acute deep venous thrombosis. It is also an established method of femoropopliteal and femorodistal arterial graft surveillance, determination of the extent and cause of chronic venous insufficiency, detection of placental insufficiency and portasystemic shunt patency, early transplant monitoring, as well as of detecting an arterial stenosis suitable for angioplasty. In addition, it is developing into the method of choice for the initial investigation of patients with suspected mesenteric or renal artery stenosis. The accuracy of duplex scanning, avoiding further unnecessary invasive and expensive diagnostic procedures, makes it one of the most cost-effective investigations ever introduced into clinical practice. Also, when used as a screening technique in arterial and venous disease, it selects those patients who need more invasive procedures such as angiography. This helps to reduce waiting lists of patients requiring investigation, and better directs limited resources to treatment rather than investigation.