Comparative Study of Non-enhanced Versus Contrast Enhanced MR Angiography in Peripheral Arterial Disease on a 3T MR Scanner.

Magnetic Resonance Angiography (MRA) of the peripheral arteries has become essential in the diagnosis and follow-up of peripheral arterial disease. In clinical routine, the acquisition uses intravenous injection of a Gadolinium based contrast agent (gadolinium chelates). Initially, contrast enhanced MR angiography (CE-MRA) was recommended for diabetic patients, elderly patients and\\or patients with chronic renal insufficiency presenting a contraindication to CT angiography using iodized contrast agent injection. However, the increase in nephrogenic systematic fibrosis clinical cases, which would be secondary to gadolinium chelates injection, in patients with chronic renal insufficiency has restricted the use of CE-MRA. More than 500 cases were described to date in the world. Its occurrence is currently estimated around 4 % for patients in terminal chronic renal insufficiency and its mortality around 30 %. According to the recommendations of AFSSAPS from August, 2007, two gadolinium contrast agents (Gadodiamide-OMNISCAN \*, General Electric HealthCare and Gadopentetate Dimeglumine-MAGNEVIST \*, Bayer HealthCare) are contraindicated if the glomerular filtration rate is lower than 30 ml/mn. Non-contrast enhanced MR angiography (NCE MRA) techniques have been proposed to provide complete and non-invasive investigation of the peripheral vasculature, from the abdominal aorta to the calf, thus offering patients with chronic renal insufficiency a surrogate with no side effects. Moreover, the use of high field (3T) MR imaging and phased array coils offers high quality images and good signal to noise ratio for peripheral vasculature analysis. Besides, the acquisition can be repeated if required as it does not require any contrast injection. The main objective is to evaluate the quality of the NCE images obtained for every investigated station from the abdominal aorta to the calf. The secondary objective is to compare the diagnostic performances of NCE images with th