Bimodal intravascular volumetric imaging combining OCT and MPI

Area of Science:

• Biomedical imaging
• Medical physics
• Vascular imaging

Background:

• Intravascular optical coherence tomography (IVOCT) provides high-resolution vessel imaging but lacks positional data.
• Magnetic particle imaging (MPI) offers 3D, radiation-free imaging with high temporal resolution and deep penetration.
• Combining IVOCT and MPI can overcome individual limitations for comprehensive vascular analysis.

Purpose of the Study:

• To develop and evaluate a simultaneous bimodal IVOCT-MPI imaging technique.
• To estimate the IVOCT catheter pullback path using 3D MPI data.
• To reconstruct the 3D shape of vessels with high accuracy.

Main Methods:

• A setup for simultaneous IVOCT and MPI acquisition was developed using vessel phantoms.
• The influence of MPI tracer concentration on IVOCT imaging was analyzed.
• Catheter pullback trajectory was estimated from MPI data for IVOCT image reconstruction.

Main Results:

• A suitable MPI tracer concentration (2.5 mmol/L) was identified with minimal impact on IVOCT signals.
• The pullback trajectory estimated from MPI showed good agreement with phantom centerlines (mean absolute error 0.25-0.28 mm).
• Vessel phantom shape reconstruction yielded low mean absolute errors for diameter (0.06-0.21 mm).

Conclusions:

• Simultaneous IVOCT-MPI imaging enables precise estimation of catheter trajectory.
• This multimodal approach accurately reconstructs 3D vessel shapes.
• The combined technique provides a radiation-free solution for high-precision vascular imaging.