Purpose: To investigate the potential of real-time magnetic particle imaging (MPI) to guide percutaneous transluminal angioplasty (PTA) of vascular stenoses in a phantom model.
Materials and methods: Experiments were conducted on a custom-built MPI scanner. Vascular stenosis phantoms consisted of polyvinyl chloride tubes (inner diameter 8 mm) prepared with a centrally aligned cable tie to form ~ 50% stenoses. MPI angiography for visualization of stenoses was performed using the superparamagnetic iron oxide nanoparticle-based contrast agent Ferucarbotran (10 mmol (Fe)/l). Balloon catheters and guidewires for PTA were visualized using custom-made lacquer markers based on Ferucarbotran. Stenosis dilation (n = 3) was performed by manually inflating the PTA balloon with diluted Ferucarbotran. An online reconstruction framework was implemented for real-time imaging with very short latency time.
Results: Visualization of stenosis phantoms and guidance of interventional instruments in real-time (4 frames/s, ~ 100 ms latency time) was possible using an online reconstruction algorithm. Labeling of guidewires and balloon catheters allowed for precise visualization of instrument positions.
Conclusion: Real-time MPI-guided PTA in a phantom model is feasible.
Keywords: Ferucarbotran; Magnetic particle imaging; Percutaneous transluminal angioplasty; Real-time; Superparamagnetic nanoparticles.