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bioRxiv · 10.64898/2026.07.10.737664

An Approach to Measure Conductivity Gradients of Brain Tissue Transitions using Electrode Arrays

Symmank, M.·Gerber, M.·Knoesche, T.·Gueresir, E.·Wilhelmy, F.·Weise, K.
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Abstract

Accurate determination of surgical margins is critical in tumor resection to ensure complete removal of tumor-infiltrated tissue while preserving healthy tissue. Pathological assessment provides reliable information but is time-consuming. This study investigates the feasibility of using impedance spectroscopy to detect tissue transitions at a macroscopic level. Two electrode arrays--one-dimensional and two-dimensional--were applied to ex vivo porcine brain tissue. Measurements were performed using both two- and four-electrode configurations, and data were corrected using the multiple-load compensation method. Results demonstrate that the one-dimensional array provides continuous conductivity profiles corresponding to tissue transitions, while the two-dimensional array showed less consistent results. These findings suggest that impedance spectroscopy is a promising tool for intraoperative margin detection, but further optimization of electrode geometry and measurement data processing is required.

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Symmank, M., Gerber, M., Knoesche, T., Gueresir, E., Wilhelmy, F., Weise, K.. 2026-07-16. An Approach to Measure Conductivity Gradients of Brain Tissue Transitions using Electrode Arrays. https://doi.org/10.64898/2026.07.10.737664

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