Magnetic Resonance Imaging of Vascular Function

Flow-mediated dilation (FMD) is a macrovascular endothelium-dependent response to distal ischemia. Impaired FMD is a precursor of atherosclerosis. In those with endothelial dysfunction, FMD can be quite small. To be able to measure changes within this small dynamic range, we need to reduce the systematic error and improve accuracy.

Ultrasound and magnetic resonance imaging have been used to measure FMD noninvasively (J Cardiovas Magn Reson. 2006;8(2);381–87). Magnetic resonance imaging is less operator-dependent and less technically challenging than is ultrasound. Magnetic resonance imaging is also able to image changes in vascular cross-sectional areas. However, current MRI techniques are limited by spatial and temporal resolution. Our study aims to improve on the current MRI techniques for measuring FMD.