Abstract：
UNASSIGNED: To use computational modeling to provide a complete and logical description of the electrical and thermal behavior during stereoelectroencephalography-guided (SEEG) radiofrequency thermo-coagulation (RF-TC).
UNASSIGNED: A coupled electrical-thermal model was used to obtain the temperature distributions in the tissue during RF-TC. The computer model was first validated by an ex vivo model based on liver fragments and later used to study the impact of three different factors on the coagulation zone size: 1) the difference in the tissue surrounding the electrode (gray/white matter), 2) the presence of a peri-electrode gap occupied by cerebrospinal fluid (CSF), and 3) the energy setting used (power-duration).
UNASSIGNED: The model built for the experimental validation was able to predict both the evolution of impedance and the short diameter of the coagulation zone (error < 0.01 mm) reasonably well but overestimated the long diameter by 2 - 3 mm. After adapting the model to clinical conditions, the simulation showed that: 1) Impedance roll-off limited the coagulation size but involved overheating (around 100 °C); 2) The type of tissue around the contacts (gray vs. white matter) had a moderate impact on the coagulation size (maximum difference 0.84 mm), and 3) the peri-electrode gap considerably altered the temperature distributions, avoided overheating, although the diameter of the coagulation zone was not very different from the no-gap case (<0.2 mm).
UNASSIGNED: This study showed that computer modeling, especially subject- and scenario-specific modeling, can be used to estimate in advance the electrical and thermal performance of the RF-TC in brain tissue.
UNASSIGNED: A coupled electrical-thermal model was used to obtain the temperature distributions in the tissue during RF-TC. The computer model was first validated by an ex vivo model based on liver fragments and later used to study the impact of three different factors on the coagulation zone size: 1) the difference in the tissue surrounding the electrode (gray/white matter), 2) the presence of a peri-electrode gap occupied by cerebrospinal fluid (CSF), and 3) the energy setting used (power-duration).
UNASSIGNED: The model built for the experimental validation was able to predict both the evolution of impedance and the short diameter of the coagulation zone (error < 0.01 mm) reasonably well but overestimated the long diameter by 2 - 3 mm. After adapting the model to clinical conditions, the simulation showed that: 1) Impedance roll-off limited the coagulation size but involved overheating (around 100 °C); 2) The type of tissue around the contacts (gray vs. white matter) had a moderate impact on the coagulation size (maximum difference 0.84 mm), and 3) the peri-electrode gap considerably altered the temperature distributions, avoided overheating, although the diameter of the coagulation zone was not very different from the no-gap case (<0.2 mm).
UNASSIGNED: This study showed that computer modeling, especially subject- and scenario-specific modeling, can be used to estimate in advance the electrical and thermal performance of the RF-TC in brain tissue.
摘要：
■要使用计算建模来提供立体脑电图引导（SEEG）射频热凝固（RF-TC）过程中的电和热行为的完整和逻辑描述。
■使用耦合的电热模型来获得RF-TC期间组织中的温度分布。计算机模型首先通过基于肝脏碎片的离体模型进行了验证，后来用于研究三个不同因素对凝血区大小的影响：1）电极周围组织（灰/白质）的差异，2）存在被脑脊液（CSF）占据的电极间隙，和3)使用的能量设置(功率持续时间)。
■为实验验证而建立的模型能够很好地预测阻抗的演变和凝固区的短径（误差<0.01mm），但高估了长径2-3mm。在使模型适应临床条件后，模拟表明：1)阻抗滚降限制了凝固的大小，但涉及过热(约100°C)；2)接触周围组织的类型(灰色与白质）对凝血大小有中等影响（最大差异0.84mm），和3)电极间隙显著改变了温度分布，避免过热，尽管凝结区的直径与无间隙情况（<0.2mm）没有太大差异。
■这项研究表明，计算机建模，特别是特定于主题和场景的建模，可用于预先估计RF-TC在脑组织中的电和热性能。
■使用耦合的电热模型来获得RF-TC期间组织中的温度分布。计算机模型首先通过基于肝脏碎片的离体模型进行了验证，后来用于研究三个不同因素对凝血区大小的影响：1）电极周围组织（灰/白质）的差异，2）存在被脑脊液（CSF）占据的电极间隙，和3)使用的能量设置(功率持续时间)。
■为实验验证而建立的模型能够很好地预测阻抗的演变和凝固区的短径（误差<0.01mm），但高估了长径2-3mm。在使模型适应临床条件后，模拟表明：1)阻抗滚降限制了凝固的大小，但涉及过热(约100°C)；2)接触周围组织的类型(灰色与白质）对凝血大小有中等影响（最大差异0.84mm），和3)电极间隙显著改变了温度分布，避免过热，尽管凝结区的直径与无间隙情况（<0.2mm）没有太大差异。
■这项研究表明，计算机建模，特别是特定于主题和场景的建模，可用于预先估计RF-TC在脑组织中的电和热性能。
