  We present a novel thermodynamic parameter estimation framework for
energy-based surgery on live tissue, with direct applications to tissue
characterization during electrosurgery. This framework addresses the problem of
estimating tissue-specific thermodynamics in real-time, which would enable
accurate prediction of thermal damage impact to the tissue and damage-conscious
planning of electrosurgical procedures. Our approach provides basic
thermodynamic information such as thermal diffusivity, and also allows for
obtaining the thermal relaxation time and a model of the heat source, yielding
in real-time a controlled hyperbolic thermodynamics model. The latter accounts
for the finite thermal propagation time necessary for modeling of the
electrosurgical action, in which the probe motion speed often surpasses the
speed of thermal propagation in the tissue operated on. Our approach relies
solely on thermographer feedback and a knowledge of the power level and
position of the electrosurgical pencil, imposing only very minor adjustments to
normal electrosurgery to obtain a high-fidelity model of the tissue-probe
interaction. Our method is minimally invasive and can be performed in situ. We
apply our method first to simulated data based on porcine muscle tissue to
verify its accuracy and then to in vivo liver tissue, and compare the results
with those from the literature. This comparison shows that parameterizing the
Maxwell--Cattaneo model through the framework proposed yields a noticeably
higher fidelity real-time adaptable representation of the thermodynamic tissue
response to the electrosurgical impact than currently available. A discussion
on the differences between the live and the dead tissue thermodynamics is also
provided.
