Thermal Model to Guide Tumor Ablation by RF Heating

描述（由申请人提供）：介入磁共振成像 （I-MRI）提供了一种图像引导的微创消融方法， 恶性肿瘤当小直径射频探头插入固体中时， 在肿瘤中，探针传递的能量产生电流， 组织到足够高的温度杀死肿瘤细胞。这个项目是 旨在量化和预测肿瘤细胞的急性反应， 射频探头内部产生的热量。定量 模型分析在处理临床的特殊挑战时是必不可少的。 例如消融关键血管或神经附近的肿瘤细胞。 此外，建模可以帮助预测烧蚀区域的变化 从具有空间变化灌注的组织中的热响应。到 为了实现这些目标，我们建议分析 射频加热周围组织的三维（3-D）温度场 消融期间的穿刺针。这一过程将使用三维生物热模型 一个包含可变热源和不同的 温度依赖性灌注，以代表与 消融术该模型将被数值求解以模拟温度 组织中的场动力学我们将验证模型并估计模型 通过比较模型预测的温度场参数， 使用凝胶体模的MRI实验的RF加热和相应数据， 切除的组织和完整的动物我们将开发更快的数值方法 用于模型方程的求解，以允许更准确、实时 消融过程中的模拟。消融分析将包括 模型参数估计的最优估计， 用于连续肿瘤消融的射频探头和图形显示。这些方法 将在治疗期间协助临床评估和决策 这是一种杀死肿瘤细胞而对正常细胞损伤最小的方法。

Description (provided by applicant): Interventional Magnetic Resonance Imaging (I-MRI) provides an image-guided, minimally invasive method for ablating cancerous tumors. When a small diameter RF probe is inserted into a solid tumor, the energy delivered by the probe produces a current that heats the tissue to a sufficiently high temperature to kill tumor cells. This project is intended to quantify and predict the acute response of tumor cells and surrounding tissue to heat produced internally with a RF probe. A quantitative model analysis is essential in dealing with special challenges for clinical implementation such as ablating tumor cells near critical vessels or nerves. Furthermore, modeling can assist in predicting changes in the ablated region from the thermal response in tissue with a spatially varying perfusion. To accomplish these goals, we propose to analyze the dynamic changes of the three-dimensional (3-D) temperature field in tissue surrounding the RF heating probe during ablation. This process will be modeled using a 3-D bio-heat equation that incorporates a variable heat source and a distinct temperature-dependent perfusion to represent changes in tissue associated with ablation. The model will be solved numerically to simulate the temperature field dynamics in tissue. We will validate the model and estimate model parameters by comparison of model predictions of the temperature field during RF heating with corresponding data from MRI experiments using gel phantoms, excised tissues, and intact animals. We will develop faster numerical methods for solution of the model equations to allow more accurate, real-time simulations during the ablation procedure. The ablation analysis will include optimal estimates of model parameter estimation, multiple repositioning of the RF probe for sequential tumor ablation, and graphical displays. These methods will assist clinical evaluation and decision-making during the therapeutic procedure to kill tumor cells with minimal damage to normal cells.