Combining Direct 3D Volume Rendering and Magnetic Particle Imaging to Advance Radiation-Free Real-Time 3D Guidance of Vascular Interventions.
PURPOSE
Magnetic particle imaging (MPI) is a novel tomographic radiation-free imaging technique that combines high spatial resolution and real-time capabilities, making it a promising tool to guide vascular interventions. Immediate availability of 3D image data is a major advantage over the presently used digital subtraction angiography (DSA), but new methods for real-time image analysis and visualization are also required to take full advantage of the MPI properties. This laboratory study illustrates respective techniques by means of three different patient-specific 3D vascular flow models.


MATERIAL AND METHODS
The selected models corresponded to typical anatomical intervention sites. Routine patient cases and image data were selected, relevant vascular territories segmented, 3D models generated and then 3D-printed. Printed models were used to perform case-specific MPI imaging. The resulting MPI images, direct volume rendering (DVR)-based fast 3D visualization options, and their suitability to advance vascular interventions were evaluated and compared to conventional DSA.


RESULTS
The experiments illustrated the feasibility and potential to enhance image interpretation during interventions by using MPI real-time volumetric imaging and problem-tailored DVR-based fast (approximately 30 frames/s) 3D visualization options. These options included automated viewpoint selection and cutaway views. The image enhancement potential is especially relevant for complex geometries (e.g., in the presence of superposed vessels).


CONCLUSION
The unique features of the as-yet preclinical imaging modality MPI render it promising for guidance of vascular interventions. Advanced fast DVR could help to fulfill this promise by intuitive visualization of the 3D intervention scene in real time.
['Weller|Dominik|D|', 'Salamon|Johannes M|JM|', 'Frölich|Andreas|A|', 'Möddel|Martin|M|', 'Knopp|Tobias|T|http://orcid.org/0000-0002-1589-8517', 'Werner|René|R|http://orcid.org/0000-0002-2296-3305']
D002343:Carotid Artery, Internal D005240:Feasibility Studies D006499:Hepatic Artery D006801:Humans D007090:Image Interpretation, Computer-Assisted D021621:Imaging, Three-Dimensional D058185:Magnetite Nanoparticles D020768:Middle Cerebral Artery D008954:Models, Biological D015642:Radiology, Interventional D014054:Tomography
Magnetic particle imaging 4D visualization Real-time image processing Vascular imaging