Approaches for image quality improvement of 4D DSA and flow quantification using 4D DSA C-arm CT angiography is an established modality for
cerebral imaging as it provides very high spatial
resolution. Acquisition of two scans, one with injected
contrast agent and a mask scan without contrast agent, 3D
digital subtraction angiography images (3D DSA) can be
computed. While this allows for excellent visualization
of the vasculature, the images are not temporally
resolved.
In contrast, traditional 2D DSA projection images provide
temporally resolved images. However, due to vessel
overlap, often multiple acquisitions are necessary,
leading to increased dose and contrast agent.
4D DSA is a first approach to combine high spatial
resolution and temporal information, using a special
image acquisition protocol. It allows us to create 3D
volumetric reconstructions of the vasculature with
additional temporal information of the blood flow, as the
contrast bolus is imaged with 30fps. However, vessel
overlap and foreshortening in the projection images can
lead to unreliable temporal information and therefore
image artifacts, thus appropriate interpolation
techniques are required.
Computational Fluid Dynamics (CFD) allows us to simulate
blood flow, given a model of the vasculature. The aim of
this project is the improvement of 4D DSA image quality
using CFD simulations and ultimately blood flow
quantification using 4D DSA. This entails an optimization
of CFD boundary conditions such that they fit to the 4D
DSA data. Based on the CFD results, 4D DSA image quality
should be improved. In turn, these results can be
iteratively be used to further refine the CFD simulation.
Finally, we aim to extract quantitative flow measurements
from 4D DSA images. | Project manager: PD Dr. Markus Kowarschik, Prof. Dr.-Ing. habil. Andreas Maier, PD Dr.-Ing. habil. Stefan Steidl
Project participants: Marco Bögel, M. Sc., Gehrisch, Sonja , Redel, Thomas
Keywords: Blood flow simulation, angiography, flow quantification
Duration: 15.6.2015 - 14.6.2017
Sponsored by: Siemens Healthcare GmbH
Contact: Maier, Andreas Phone +49 9131 85 27883, Fax +49 9131 85 27270, E-Mail: andreas.maier@fau.de
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