University thesis:
Dissertation, Albert-Ludwigs-Universität Freiburg, 2020
Footnote:
Description:
Abstract: Cardiovascular diseases are the most common cause of death worldwide and are of great interest in clinical and preclinical research. Cardiovascular magnetic resonance imaging (MRI) can reveal pathological changes of the vascular system and is widely used in clinical diagnostic. The major remedy of MRI are long measurement times or limited temporal and spatial resolution. <br>So-called phase-contrast MRI can quantify tissue and blood velocities besides providing conventional magnitude images. It allows to visualize and quantify complex flow patterns, for example in the aorta or the carotid arteries. Longitudinal monitoring of the development and treatment of cardiovascular diseases in humans is limited by several factors, e.g. ethical reasons or slow disease progression over years. Knock-out models in preclinical research can reflect specific human diseases and overcome the limitations of research in humans. There is great interest in using cardiovascular MRI in mice, however cardiovascular MRI in mice is challenging due to the small size of the mouse and its fast heartbeat. Dedicated developments are necessary to translate common human imaging techniques to mice. <br>In this work, two methods were developed and verified to measure and quantify complex blood flow in the mouse aortic arch. A prospectively gated Cartesian phase contrast sequence and a retrospectively gated radial phase contrast sequence were developed and compared against each other. A combined parallel imaging and compressed sensing reconstruction was implemented that allows to reduce measurement time to 32 minutes with an isotropic resolution of 138 μm. An interactive application was developed to analyze and quantify the acquired velocity data. As a proof of concept the radial method was applied to a mouse model of disease (ApoE-/- knock-out). The measured blood flow was related to plaque burden in the aortic arch ,which was obtained from histology