Comparing Subjects with Reference Populations - A Visualization Toolkit for the Analysis of Aortic Anatomy and Pressure Distribution.

The analysis of anatomical and hemodynamic vessel parameters plays an important role in diagnosis and therapy planning for aortic diseases. Normal values and decision thresholds are usually based on global or local parameters provided by population studies. In order to enable a more holistic comparison of a single subject and a matching reference population we have developed a spatiotemporal normalization concept for the analysis of 4D PC MRI data of the thoracic aorta. This enables the comparison of geometric properties and pressure differences along the vessel course as well as in a sector model, which represents a cross-sectional value distribution. We tested the applicability of the presented approach by comparing subjects with aortic diseases to matching subgroups of a normal reference population. The presented framework enabled a visual and quantitative assessment of the local geometric and pressure distribution changes of different pathological alterations of the aorta. It will be extended to integrate further hemodynamic properties and larger reference cohorts to support clinical decision making based on hemodynamic information in near future.