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Updated: May 13, 2026
On-Site Sampling and Extraction of Brain Tumors for Metabolomics and Lipidomics Analysis
Published on: May 31, 2020
Impedance spectroscopy--an outstanding method for label-free and real-time discrimination between brain and tumor
Heinz-Georg Jahnke1, Axel Heimann, Ronny Azendorf
1Center for Biotechnology and Biomedicine (BBZ), Deutscher Platz 5, Leipzig, Germany. heinz-georg.jahnke@bbz.uni-leipzig.de
Abstract:
Until today, brain tumors especially glioblastoma are difficult to treat and therefore, results in a poor survival rate of 0-14% over five years. To overcome this problem, the development of novel therapeutics as well as optimization of neurosurgical procedures to remove the tumor tissue are subject of intensive research. The main problem of the tumor excision, as the primary clinical intervention is the diffuse infiltration of the tumor cells in unaltered brain tissue that complicates the complete removal of residual tumor cells. In this context, we are developing novel approaches for the label-free discrimination between tumor tissue and unaltered brain tissue in real-time during the surgical process. Using our impedance spectroscopy-based measurement system in combination with flexible microelectrode arrays we could successfully demonstrate the discrimination between a C6-glioma and unaltered brain tissue in an in vivo rat model. The analysis of the impedance spectra revealed specific impedance spectrum shape characteristics of physiologic neuronal tissue in the frequency range of 10-500 kHz that were significantly different from the tumor tissue. Moreover, we used an adapted equivalent circuit model to get a deeper understanding for the nature of the observed effects. The impedimetric label-free and real-time discrimination of tumor from unaltered brain tissue offers the possibility for the implementation in surgical instruments to support surgeons to decide, which tissue areas should be removed and which should be remained.
Insights
Researchers developed a novel impedance spectroscopy system to differentiate brain tumors from healthy tissue in real-time. This technology aids surgeons in complete tumor removal, potentially improving patient survival rates for glioblastoma.
Area of Science:
- Biomedical Engineering
- Neuro-oncology
- Surgical Technology
Background:
- Glioblastoma and other brain tumors have poor prognoses due to treatment challenges and incomplete surgical resection.
- Diffuse infiltration of tumor cells into healthy brain tissue complicates complete tumor excision.
- Current methods lack real-time capability for distinguishing tumor margins from normal brain tissue during surgery.
Purpose of the Study:
- To develop a label-free, real-time measurement system for discriminating between tumor and healthy brain tissue.
- To enhance neurosurgical procedures by providing intraoperative guidance for complete tumor removal.
- To investigate the potential of impedance spectroscopy for real-time surgical decision-making.
Main Methods:
- Utilized impedance spectroscopy with flexible microelectrode arrays.
- Tested the system in an in vivo rat model with C6-glioma.
- Analyzed impedance spectra in the 10-1500 kHz frequency range and employed an equivalent circuit model.
Main Results:
- Successfully discriminated between C6-glioma and unaltered brain tissue in real-time.
- Identified distinct impedance spectrum characteristics for physiological neuronal tissue versus tumor tissue.
- An adapted equivalent circuit model provided insights into the underlying biophysical mechanisms.
Conclusions:
- Impedance spectroscopy offers a promising label-free, real-time method for intraoperative tumor margin delineation.
- This technology can potentially improve surgical outcomes by guiding the removal of residual tumor cells.
- Integration into surgical instruments could significantly aid surgeons in differentiating tumor from healthy brain tissue.
