A model of tissue contraction during thermal ablation
Journal
Physiological Measurement
Journal Volume
37
Journal Issue
9
Pages
1474-1484
Date Issued
2016
Author(s)
Abstract
A model of a globular protein is used to describe the contraction of tissue exposed to elevated temperatures. This will be useful in predicting the contraction of tissue that is observed during thermal ablation of tumours, which is a problem when trying to determine the ablation zone in post-operative images. The transitions between the states of the protein can be related to a change in the length of the molecule, which can be directly observed as a change in the length of the tissue. A three state model of a globular protein is used to describe the contraction of tissue exposed to elevated temperatures. A nonlinear fitting algorithm is considered here to fit available experimental data and thus to obtain the values of the model parameters. A sensitivity analysis of the proposed mathematical model is performed to determine the most important parameters in the model. The model parameters were obtained from experimental data of isothermal free shrinkage experiments. The predictions of the complete model show similar agreement with the data, well within the experimental error of 10%. The overall activation energy and frequency factor were found to be 201 kJ mol-1 and s-1 respectively. The results show that the experimental data were well described by the three state model considered here. Furthermore, it was possible to determine the most sensitive parameters in the model. The model presented here will allow predictions of thermal ablation to be corrected for tissue shrinkage, thus improving mathematical simulations for treatment planning, although clinical translation will require adapting the model from experimentally obtained tendon data to soft tissue data. ? 2016 Institute of Physics and Engineering in Medicine.
Subjects
Ablation
Activation energy
Forecasting
Proteins
Sensitivity analysis
Tissue
Arrhenius equation
Elevated temperature
Exposed to
Free shrinkages
Globular proteins
Modeling parameters
Nonlinear fitting algorithms
Thermal ablation
Three-state models
Tissue contraction
Shrinkage
protein
ablation therapy
biological model
biomechanics
chemistry
heat
mechanics
metabolism
Ablation Techniques
Biomechanical Phenomena
Hot Temperature
Mechanical Phenomena
Models, Biological
Type
journal article