In a significant advancement for biomedical engineering, researchers have developed a new piezoelectric vibration technology that promises to enhance minimally invasive surgical techniques. This innovation, detailed in a recent paper published in Cyborg and Bionic Systems, offers a solution to the challenges faced in procedures like neural probe implantation and ophthalmic surgery by enabling precise penetration of biological membranes with minimal tissue damage.
The study, led by Bingze He from Shanghai Jiao Tong University, introduces an integrated piezoelectric module that combines vibration-assisted penetration with real-time force sensing. This development addresses the limitations of traditional methods, which often rely on sharp micro-tools or robotic systems that can cause rapid insertion speeds, increasing the risk of tissue damage and inflammation.
Revolutionizing Tissue Penetration Techniques
The integrated piezoelectric module (IPEM) is a compact design that merges driving and sensing functions into a single component. It uses two piezoelectric ceramic discs (PZT), where one acts as the actuator generating axial micro-vibrations, and the other serves as the sensor monitoring force changes during tissue interaction. This dual-functionality allows for efficient tissue penetration and real-time feedback without the need for external sensors.
The module’s working principle is rooted in the piezoelectric effect: the driving PZT generates micro-vibrations through the inverse piezoelectric effect, while the sensor PZT detects forces via the direct piezoelectric effect. This innovative design promises to reduce insertion forces and provide accurate force feedback, enhancing the precision and adaptability of current systems.
Performance and Validation
The authors conducted extensive testing to validate the module’s performance. Finite element analysis and laser Doppler vibrometry confirmed its ability to generate significant axial micro-vibrations at a resonant frequency of 4652 Hz. In vibration experiments, the module achieved an axial displacement of ±9.6 μm at 4.6 kHz, demonstrating excellent axial vibration capabilities.
For force sensing, both static and dynamic calibration tests were performed. The module showed a strong linear relationship in static loading, with a correlation coefficient of 0.9998 and a sensitivity of 9.3 mV/mN. During dynamic tests, it accurately tracked force changes under various loading conditions, maintaining error within ±0.2 mN.
Practical applications were also explored through gelatin phantom and in vivo mouse brain penetration experiments. The results were promising: the maximum puncture force was reduced by about 13% in gelatin tests and by 33% in mouse brain experiments, highlighting the module’s effectiveness in minimizing trauma during penetration.
Challenges and Future Directions
Despite its promising performance, the module faces several challenges. Electrical noise in dynamic conditions may affect precision, particularly in noisy surgical environments, necessitating advanced noise filtering techniques. Environmental factors like temperature and humidity could also impact the piezoelectric material’s performance.
Moreover, while the module’s resonant frequency is optimized for soft tissues, adjustments may be required for harder tissues due to impedance mismatches. The response time may lag during high-speed insertions, indicating a need for further optimization. Bingze He noted, “While the module performs well in single-point penetration, its application in more complex scenarios, such as multi-channel or array electrode implantation, still requires further validation.”
This research, supported by the Shanghai Municipal Science and Technology Major Project, represents a significant step forward in the field of minimally invasive surgery. The paper, authored by Bingze He, Yao Guo, and Guangzhong Yang, is titled “Integrated Piezoelectric Vibration and In Situ Force Sensing for Low-Trauma Tissue Penetration” and was published on October 21, 2025, at DOI: 10.34133/cbsystems.0417.
As the medical community continues to seek innovations that reduce surgical trauma and improve patient outcomes, this piezoelectric vibration technology could play a pivotal role in the evolution of surgical techniques, particularly in delicate procedures such as brain-machine interfaces and microsurgical neural implantations.
