Magnetic resonance angiography and computed tomography angiography for peripheral arterial disease

Abstract

•. Non-invasive imaging, with either MR angiography (MRA) or CT angiography (CTA), is now the first choice technique having supplanted invasive diagnostic arteriography for the initial evaluation of peripheral arterial disease in many situations. •. For both CTA and MRA the interpretation of source images at a workstation is essential along with more advanced visualisation tools. •. CTA is particularly useful for assessment of abdominal aneurysm morphology and in the emergency setting. •. Accurate assessment of stenoses may be difficult with CTA in the presence of calcified plaque, particularly in smaller vessels. •. Gadolinium contrast-enhanced MRA has the most evidence for lower limb arterial assessment, particularly in critical ischaemia. •. Optimal MRA of the tibial arteries is best performed with a dedicated station including time-resolved techniques, especially in critical ischaemia. •. MRA blood pool techniques can further improve visualisation and afford the opportunity for concomitant venous imaging for added value. CT angiography (CTA) and MR angiography (MRA) have both now evolved into excellent techniques for imaging the lower limb vasculature with a studied accuracy close to the compared standard of invasive angiography. Their advantages include three-dimensional visualisation, extraluminal evaluation, rapid performance and a cost-effective out-patient technique; all without the inherent risks associated with arterial vascular puncture. This review provides an update on the current state of the art for both techniques including discussions on scanning protocols and visualisation methods, as well as clinical applications, common pitfalls and the future trends for both modalities.