Phase-Lag-Based MPS/MPI Dual-Mode Precise In Vivo Temperature Imaging Technique.

Area of Science:

• Biomedical Engineering
• Medical Imaging
• Nanotechnology

Background:

• Magnetic Particle Imaging (MPI) offers noninvasive temperature mapping without depth limits.
• Current MPI applications are hindered by calibration challenges, including environmental mismatch and infeasibility for in vivo use.
• Accurate temperature monitoring is crucial for applications like magnetic hyperthermia.

Purpose of the Study:

• To develop a novel in vivo temperature imaging method using a dual-mode MPS/MPI system.
• To address limitations in current MPI calibration strategies for in vivo environments.
• To enhance the accuracy and stability of temperature mapping for clinical applications.

Main Methods:

• Utilized magnetic particle spectroscopy (MPS) to analyze harmonic phase responses of magnetic nanoparticles (MNPs) in vivo and in vitro.
• Developed a multi-layer perceptron (MLP) based calibration strategy to account for non-ideal temperature-phase relationships.
• Integrated multi-parameter information into a unified network for robust temperature reconstruction.

Main Results:

• The proposed method reduced in vivo temperature reconstruction error by approximately 17.24% compared to conventional methods.
• Achieved an average absolute temperature error below 1.257 °C in comprehensive experiments.
• Demonstrated successful in vivo temperature imaging with improved accuracy and stability.

Conclusions:

• The novel dual-mode MPS/MPI system provides a feasible and accurate solution for in vivo temperature imaging.
• The proposed calibration strategy effectively overcomes environmental mismatch and non-ideal signal deviations.
• This advancement offers critical technical support for temperature-sensitive medical applications, particularly magnetic hyperthermia.