Quantification of the effect of electrical and thermal parameters on radiofrequency ablation for concentric tumour model of different sizes

A new approach to feedback control of radiofrequency ablation systems for large coagulation zones

“…The first issue is the determination of the set-point temperature. The idea proposed in the present study was that the set-point temperature was neither 100 C [19,20] nor 50 C [21,40] but should be determined based on the critical moment (see its definition in the above discussion). In the present study, a trialand-error process was taken to determine the set-point temperature by making it as high as possible before the critical moment occurs.…”

“…There have been many studies reported in the literature to address the foregoing problem with RFA. There are four areas of research to address this problem: (i) power delivery mode such as in pulsed or continuous fashion, [15][16][17][18] (ii) the feedback control law, for example proportional-integralderivative (PID) [19] or proportional-integral (PI), [20,21] (iii) the information to be fed-back (temperature at the tissue, temperature at the active tip, or impedance between the active tip and the grounding pad), [19][20][21][22][23] and (iv) the change in tissue characteristics (e.g. the tissue dehydration), which allows more power to be delivered.…”

Sensitivity analysis of critical parameters affecting the efficacy of microwave ablation using Taguchi method

“…Further, as outlined by Taguchi's procedure, the output (ie, ablation volume) of each experiment is converted into signal‐to‐noise (S/N) ratio in order to measure the quality characteristics deviating from the desired values. Three approaches, as follows, the smaller‐the‐better , the larger‐the‐better and the nominal‐the‐better are available in accordance to Taguchi's philosophy . Since, the objective of the present study is to maximize the ablation volume, thus, the larger‐the‐better category has been implemented whereby the S/N ratio is given by …”

“…Three approaches, as follows, the smaller-the-better, the larger-the-better and the nominal-the-better are available in accordance to Taguchi's philosophy. 32 Since, the objective of the present study is to maximize the ablation volume, thus, the larger-the-better category has been implemented whereby the S/N ratio is given by 33 where V i refers to the output value (ie, ablation volume) of the experiment (simulation) i in Taguchi's L27 orthogonal array (refer Table 4).…”

Bi-component conformal electrode for radiofrequency sequential ablation and circumferential separation of large tumours in solid organs: development and in-vitro evaluation

“…FEM modelling was used to analyses radiofrequency cancer ablation [17] by solving RF Joule (resistive) heating and Penne's bio-heat equation [18]. FEM modelling was further used to study the influence of blood vessel on the thermal lesion formation (the heat sink effects) during RFA [19] and the influence of other parameters such as water evaporation [20] and tissue conductivities with efficient RFA experiment design [21,22]. In this study, an anatomical 3D FEM model was used for RFA simulation.…”