Phase-sensitive signal processing for improved usability of the DiffMag handheld probe.

Area of Science:

• Biomedical Engineering
• Surgical Oncology
• Nanotechnology

Background:

• Sentinel lymph node biopsy (SLNB) is crucial for cancer staging.
• Current SLNB methods use radioactive tracers, posing challenges.
• Superparamagnetic iron oxide nanoparticles (SPIONs) offer a magnetic alternative but face specificity and interference issues.

Purpose of the Study:

• To develop and validate a phase-sensitive detection algorithm for handheld magnetometers.
• To improve the specificity and reduce motion artefacts in SPION-based SLNB detection.
• To enhance the clinical utility of magnetic detection in metal-rich surgical environments.

Main Methods:

• Development of a phase-sensitive detection algorithm for differential magnetometry.
• Integration of the algorithm into the DiffMag handheld (DMH) probe.
• Validation through benchtop experiments and a clinical usability study.

Main Results:

• The algorithm successfully distinguished SPION signals from motion artefacts.
• Enhanced detection accuracy was achieved in simulated metal-rich surgical settings.
• The phase-sensitive approach demonstrated improved reliability of magnetic detection.

Conclusions:

• The developed algorithm significantly increases the usability of handheld magnetometers for SLNB.
• This technology has the potential to make SPION-based lymph node staging more reliable.
• It addresses a key limitation for magnetic detection in complex surgical environments.