A silicon electro-mechano tissue assay surgical tweezer

Surgeons make decisions on the use of different surgical tools providing a spectrum of contact forces to cut and manipulate tissue. These decisions are mostly made without quantitative data about the mechanical integrity and mechanical properties of the tissue. Here we report on an instrumented silicon tweezer for characterizing the electromechanical properties of tissue that is being tweezed by the device. The tweezer is designed for characterizing tissue during surgical procedures. This silicon tweezer was designed with a spring constant of 9 N/m, and maximum silicon stress of 80.7 MPa during the tweezing motion to prevent silicon fracture. Multiple thin-film sensors are integrated along with the silicon tweezer, four sets of strain gauges, two sets of permittivity sensors and sixteen platinum bio-potential recording electrodes. Therefore, insertion force, permittivity and electrical properties of tissue can be monitored simultaneously at different locations provide fast information in time critical surgeries. A set of piezoelectric transducers is attached on the legs of the tweezer for gap monitoring with 20 μm displacement resolution. The tissue stiffness can then be estimated by the measured through applied force and distance variation. This device addresses a key problem during intestinal anastomoses surgical operation where stapling devices are used to seal tissue.