CTA is considered highly specific and sensitive in the evaluation of PAD. It is particularly useful for the evaluation of inflow disease and for assessment of stent and bypass graft patency. It is relatively inexpensive and quick; however, major disadvantages include radiation exposure and the use of intravenous iodinated contrast.
PERIPHERAL ARTERY DISEASE (PAD)
Computed Tomography Angiography (CTA)
Magnetic Resonance Angiography (MRA)
MRA is comparable to CTA for the evaluation of PAD, particularly in the assessment of inflow disease and bypass graft patency. MRA does not use ionizing radiation; however, it is more time-consuming and costly and may be contraindicated in certain patients (e.g. those with pacemakers/defibrillators). In addition, the risk of nephrogenic systemic fibrosis with the use of gadolinium has also been observed in patients with stage 4 or 5 chronic kidney disease . Limitations of MRA also include suboptimal assessment of peripheral stents due to artifact.
Digital Subtraction Angiography (DSA)
DSA remains the gold standard in arterial imaging. However due to its inherent risks, which include invasive arterial access, ionizing radiation, and iodinated contrast, DSA is usually reserved for patients undergoing revascularization.
22. Markmann P, Skov L, Rossen K, et al. Nephrogenic systemic fibrosis: suspected causative role of gadodiamide used for contrast-enhanced magnetic resonance imaging. J Am Soc Nephrol. 2006;17:2359-2362.