Magnetic resonance morphological, chemical shift and flow imaging in peripheral vascular disease.

We have used magnetic resonance imaging to study the aorto-iliac region in 13 patients with peripheral disease. Five healthy volunteers were studied for comparison. Magnetic resonance spin-echo imaging, chemical shift imaging to determine lipid content of atheroma, phase-shift velocity mapping and quantitative flow studies were obtained and the findings compared with radiological angiograms. The velocity profiles study showed an increased velocity at the site of a stenosis in eight patients who had iliac artery disease. Quantitative flow measurements made in both iliac arteries and the aorta in five patients and five volunteers showed a flow ratio in both iliac arteries less than 0.85 in patients with a stenosis of one iliac artery and a ratio greater than 0.85 in the volunteers. In one patient studied before and after angioplasty, flow improved post-angioplasty. The flow curve showed a characteristic distortion in diseased vessels compared with healthy vessels. In the chemical shift images of aortic atheroma five were classified as fibrous and three were lipid rich. This preliminary study showed the potential of magnetic resonance to assess non-invasively the morphology, composition and the haemodynamic significance of atheroma. This could be important in the study of the progression of peripheral vascular disease and its response to pharmacological and surgical intervention and in the planning treatment of lesions.