Theoretical modeling for radiofrequency ablation: state-of-the-art and challenges for the future

Abstract

Radiofrequency ablation is an interventional technique that in recent years has come to be employed in very different medical fields, such as the elimination of cardiac arrhythmias or the destruction of tumors in different locations. In order to investigate and develop new techniques, and also to improve those currently employed, theoretical models and computer simulations are a powerful tool since they provide vital information on the electrical and thermal behavior of ablation rapidly and at low cost. In the future they could even help to plan individual treatment for each patient. This review analyzes the state-of-the-art in theoretical modeling as applied to the study of radiofrequency ablation techniques. Firstly, it describes the most important issues involved in this methodology, including the experimental validation. Secondly, it points out the present limitations, especially those related to the lack of an accurate characterization of the biological tissues. After analyzing the current and future benefits of this technique it finally suggests future lines and trends in the research of this area.

An Analytical Solution for a Bio-heat Transfer Problem

“…In addition, the dependence of the temperature as function of RF power delivery during AF ablation, and of duration of RF applications, is other of the upgrades. Since the data are of extreme importance on the convergence tests in numerical methods (see [4,10] and the references therein), the presented solution maybe a tool before getting into highly detailed and more anatomically appropriate numerical models to design therapy. Moreover, it allows a quantitative study.…”

“…For the sake of simplicity in notations, we will omit the index i, keeping in mind that J • E corresponds to a well-determined interval of time. We find the atrial, fat and esophageal temperatures, adapting the Fourier method of separation of variables [29], as T a (x,z,t) = a 0 cos(a 1 x + a 2 ) cos(a 3 z +a 4 Notice that some other forms of solutions of PDE clearly do not fulfill the transmission, boundary, and initial conditions. Indeed, it is upon the presence of our transmission, boundary, and initial conditions, that the choice of the above functions is suitable for the mathematical model.…”

On Understanding of the Limiting Factors in Radiofrequency Ablation on Target Tissue Necrosis Volume

“…So these debates are mainly based on the ablative time, the tissue being heated, and the rate of heat increase [31]. However, 50 appears to be a standard endpoint for thermal ablation therapies in many theoretical studies, in vitro experiments, and current clinical practices [32]. Thus, in present study, a 50 isothermal contour was chosen to calculate the volume of TTN.…”

Fourier, hyperbolic and relativistic heat transfer equations: a comparative analytical study

“…It has been broadly used in many procedures such as eliminating cardiac arrhythmias [1] and destroying tumours [2]. Theoretical modelling has been proposed as a fast and inexpensive approach to developing new EBATs and studying the electrical and thermal phenomena involved in the ablative process [3]. To date, most of these models have employed the bioheat equation proposed by Pennes [4] (Fourier's theory heat equation, FHE), in which the heat conduction term is based on Fourier's theory and the heat flux q(x, t) is q(x, t) = −k∇T(x, t), (1.1) where k is thermal conductivity and T(x, t) temperature.…”