The potential of MRI for abdominal aortic aneurysm management

This thesis explores the potential role of magnetic resonance imaging (MRI) in managing abdominal aortic aneurysms (AAAs) as an alternative to conventional imaging strategies, including computed tomography angiography (CTA) and ultrasound (US). To investigate this potential, a series of pilot studies were performed to assess the utility and added value of MRI in different phases of AAA management, including surveillance, EVAR planning and sizing, and follow-up after EVAR. First, we conducted a scoping review to summarize research performed in both human and animal studies on quantitative (q)MRI techniques and the biomarkers derived from them. Second, we found good reproducibility of 4D flow MRI-derived hemodynamic parameters in AAA using voxelwise analysis of two scans acquired one week apart. Next to that, we developed an automated post-processing pipeline for 4D flow MRI in AAA patients with integrated aneurysm identification through segmentation, blood flow visualization, and quantification of hemodynamic parameters. The automated post-processing pipeline was used to analyze longitudinal changes in 4D flow MRI-derived parameters of AAA patients scanned with a half-year interval and compared with aortic diameter growth. An inverse correlation was observed between the change in minimum peak wall shear stress and AAA lumen volume over six months. A non-contrast MRI acquisition was developed for endovascular aneurysm repair (EVAR) planning, with considerable promise for integration into routine clinical workflows as assessed by several end-users. Finally, the potential of dynamic contrast-enhanced (DCE) MRI to detect and quantify endoleaks in AAA patients who underwent EVAR was demonstrated and compared to CTA.