RF tumour ablation: computer simulation and mathematical modelling of the effects of electrical and thermal conductivity.
RF tumour ablation: computer simulation and mathematical modelling of the effects of electrical and thermal conductivity.
复制标题
射频肿瘤消融：电导率和导热率影响的计算机模拟和数学建模。
DOI：
10.1080/02656730400001108
复制
发表时间：
2005
期刊：
影响因子：
--
通讯作者：
Goldberg,SN
中科院分区：
文献类型：
--
作者：
Lobo,SM;Liu,Z-J;Yu,NC;Humphries,S;Ahmed,M;Cosman,ER;Lenkinski,RE;Goldberg,W;Goldberg,SN
This study determined the effects of thermal conductivity on RF ablation tissue heating using mathematical modelling and computer simulations of RF heating coupled to thermal transport. Computer simulation of the Bio-Heat equation coupled with temperature-dependent solutions for RF electric fields (ETherm) was used to generate temperature profiles 2 cm away from a 3 cm internally-cooled electrode. Multiple conditions of clinically relevant electrical conductivities (0.07–12 S m−1) and ‘tumour’ radius (5–30 mm) at a given background electrical conductivity (0.12 S m−1) were studied. Temperature response surfaces were plotted for six thermal conductivities, ranging from 0.3–2 W m−1°C (the range of anticipated clinical and experimental systems). A temperature response surface was obtained for each thermal conductivity at 25 electrical conductivities and 17 radii (n= 425 temperature data points). The simulated temperature response was fit to a mathematical model derived from prior phantom data. This mathematical model is of the form (T=a+bRcexpdRσfexpgσ) for RF generator-energy dependent situations and (T=h+kexpmR+nexppσ) for RF generator-current limited situations, whereTis the temperature (°C) 2 cm from the electrode anda,b,c,d,f,g,h,k,m,nandpare fitting parameters. For each of the thermal conductivity temperature profiles generated, the mathematical model fit the response surface to anr2of 0.97–0.99. Parametersa,b,c,d,f,kandmwere highly correlated to thermal conductivity (r2= 0.96–0.99). The monotonic progression of fitting parameters permitted their mathematical expression using simple functions. Additionally, the effect of thermal conductivity simplified the above equation to the extent thatg,h,nandpwere found to be invariant. Thus, representation of the temperature response surface could be accurately expressed as a function of electrical conductivity, radius and thermal conductivity. As a result, the non-linear temperature response of RF induced heating can be adequately expressed mathematically as a function of electrical conductivity, radius and thermal conductivity. Hence, thermal conductivity accounts for some of the previously unexplained variance. Furthermore, the addition of this variable into the mathematical model substantially simplifies the equations and, as such, it is expected that this will permit improved prediction of RF ablation induced temperatures in clinical practice.
