A TACTILE SENSOR FOR DIFFERENTIATION OF TISSUE IN MINIMALLY INVASIVE ENT SURGERY

Background: In endoscopic surgery, stereoscopic Vision and tactile inf ormation about tissue consistency are no longer available to the surge on. Methods: To compensate for these sensory deficits, Various tissues can be characterized with an electromechanical sensor that records th eir resonance frequencies. in the future, the sensor will be integrate d into surgical instruments, providing the surgeon with information ab out tactile properties of the tissue. We determined the impedance of t issues removed interoperatively (nasal polyps, lymph nodes, cartilage, bone) and different bony structures in a skull specimen. The examinat ions were carried out with an experimental setup and subsequently with a prototype of the tactile sensor. Results: Resonance frequency incre ased with tissue hardness. Measurements with the experimental setup sh owed resonance frequencies for soft tissues between 15 and 30 Hz. We f ound that the bony septa of the ethmoid have a resonance frequency of 240-320 Hz and the thicker bony structures at the frontal skull base h ave a frequency of 780-930 Hz. Measurements of tumors in the upper aer odigestive tract showed that it is possible to differentiate between h ealthy mucosa, carcinomateous infiltrated mucosa, and carcinomateous u ndermined mucosa. In case of undermining tumor, the resonance frequenc y was one third higher than healthy mucosa. These results obtained wit h the experimental setup were reproduced with the tactile sensor proto type. Conclusions: The use of tactile information in endoscopic otolar yngological surgery may improve intraoperative tissue differentiation in the future. The safety of minimal invasive operations in head and n eck surgery can be increased.