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Comparative study on the insertion behavior of cerebral microprobes
Neda Haj Hosseini1, Rudiger Hoffmann, Sebastian Kisban
1Department of Microsystems Engineering (IMTEK), Microsystems Materials Laboratory (MML), University of Freiburg, Georges-Koehler-Allee 103, D-79110 Freiburg, Germany.
Summary
Probe insertion into brain tissue was studied using various materials and speeds. Reduced interfacial area and high speed insertion can minimize tissue trauma and dimpling, enabling in vivo use of fragile silicon probes.
Area of Science:
- Biomedical Engineering
- Neuroscience
- Materials Science
Background:
- Accurate and safe insertion of probes into brain tissue is critical for neuroscientific research and clinical applications.
- Understanding the mechanical interactions between insertion probes and brain tissue is essential for minimizing damage.
Purpose of the Study:
- To compare the insertion behavior, forces, and dimpling of different probe materials (silicon, glass, tungsten, polyimide) in a brain phantom.
- To identify optimal insertion parameters and probe designs for balancing needle stability and minimizing tissue trauma.
- To evaluate the feasibility of in vivo insertion and retraction of fragile probes.
Main Methods:
- Experiments were conducted using a developed brain phantom with probes made from silicon, glass, tungsten, and polyimide.
- Insertion behavior, forces, and dimpling were systematically measured and compared.
- In vitro and in vivo models were utilized for validation.
Main Results:
- Reduced interfacial area between the needle tip and brain tissue correlated with decreased insertion force.
- High insertion speed (100 mm/min) was found to reduce dimpling but did not necessarily decrease penetration force.
- Fragile silicon probes were successfully inserted and retracted in vivo without requiring pia and/or dura removal.
Conclusions:
- Optimizing probe design and insertion parameters, such as reducing interfacial area and controlling speed, can mitigate tissue trauma during brain probe insertion.
- The findings support the potential for in vivo application of delicate silicon probes in neurological studies.
