Identification of Surgical Instruments Using a Low Frequency Magnetic Field

Abstract

Background: As part of a open surgical intervention, it is desirable to identify, track and count the surgical instruments used, in order to document and potentially optimize the process. In the past, various technologies have been proposed to this end, as e.g. RFIDs attached to or included in the instruments, contact-less identification by image analysis or (bar-, QR-) codes, or counting by human resources, but all of them having their individual drawbacks. Objective: We present and evaluate a new method to identify metallic-conductive surgical instruments using Low Frequency (LF) magnetic fields. Method: The investigated LF magnetic field approach is based on the IndLoc system developed by the Fraunhofer IIS - originally for metallic asset identification within the field of supply chain management - and is applied on small collection of 13 typical surgical tools (four scissors, two needle holders, four tweezers, two retractors, a bone curette) for open surgery. Results: 9 out of the 13 instruments can be correctly identified, two pairs (2 short and 2 medium tweezers) are too self-similar and could not discriminated correctly from each other. Conclusion: These initial experiments show that an LF-based identification of metallic surgical tools is feasible, but the system needs to be modified (with more and smaller coils) to increase the geometrical resolution to better distinguish between self-similar and potentially more objects.

Keywords

• surgical instruments
• instrument identification
• lf magnetic field
• fingerprinting