SYSTEMS AND METHODS FOR ESTIMATING TISSUE PARAMETERS USING SURGICAL DEVICES

摘要

Systems and methods for estimating tissue parameters, including mass of tissue to be treated and a thermal resistance scale factor between the tissue and an electrode of an energy delivery device, are disclosed. The method includes sensing tissue temperatures, estimating a mass of the tissue and a thermal resistance scale factor between the tissue and an electrode, and controlling an electrosurgical generator based on the estimated mass and the estimated thermal resistance scale factor. The method may be performed iteratively and non-iteratively. The iterative method may employ a gradient descent algorithm that iteratively adds a derivative step to the estimates of the mass and thermal resistance scale factor until a condition is met. The non-iterative method includes selecting maximum and minimum temperature differences and estimating the mass and the thermal resistance scale factor based on a predetermined reduction point from the maximum temperature difference to the minimum temperature difference.

主权项

1. A system comprising:
a generator including:
an output stage configured to generate energy to treat tissue;a plurality of voltage and current sensors configured to sense voltage and current waveforms of the generated energy; anda controller coupled to the output stage to control the output stage; and an energy delivery device coupled to the generator, the energy delivery device configured to deliver the generated energy to the tissue, wherein the controller includes:
a signal processor configured to:
estimate a change in tissue impedance based on the sensed voltage and current waveforms;estimate a change in tissue temperature based on the change in tissue impedance; andestimate mass of the tissue and a thermal resistance scale factor of the tissue and the energy delivery device based on the change in tissue temperature and known parameters of the energy delivery device; andan output controller configured to generate a control signal to control the output stage based on the estimated mass and the estimated thermal resistance scale factor.