A longstanding aim of radiologic research has been the development of accurate noninvasive angiographic techniques. Nuclear magnetic resonance imaging (MRI) is sensitive to flowing protons and may achieve this goal. The research project plans to assess the capabilities of new, commercially available magnetic resonance imagers to detect simple and complex flow fields. It is planned to construct a general, MRI- compatible flow phantom system capable of creating steady and pulsatile flow in models of the cardiovascular system such as straight and curved tubes with stenoses, the aorta, and the pulmonary artery. The specific goals of this study are to: a. develop a general flow system capable of accommodating a range of simple and complex models (phantoms) which is compatible with the high magnetic fields utilized in MRI, b. test flows through established models of the cardiovascular system by MRI and laboratory flow visualization using hydrogen bubbles and dye injection, and c. correlate the MRI images with the fluid mechanic physics to define the limits and capabilities of existing MRI techniques. The results of this study should allow new MRI pulse sequences to be developed to improve the accuracy and range of flow measurements by MRI and further the development of non-invasive arteriography.
