Impedance Estimation of Soft Tissue Using Ultrasound Signal

This paper proposes a new impedance estimation method for soft tissue using ultrasound. This method estimates the impedance distribution inside an object. An ultrasound probe, which is attached to a force sensor, compresses soft tissue and observes the deformation process of tissue while measuring reaction force. The impedance parameters are then estimated based on this information. Experiments were conducted under two conditions, a static analysis and a dynamic analysis. In the static analysis, the ultrasound probe compressed the soft tissue slowly while keeping a balance of the power. In the dynamic analysis, the probe compressed tissue dynamically, and the deformation process of the soft tissue was observed. Experimental results demonstrated that our method can estimate the impedance of a soft object.