Cytotoxic Heat Transfer and Thrombotic Risk in Microwave Tumor Ablation

微波肿瘤消融中的细胞毒性热传递和血栓形成风险

• 批准号: 8725603
• 负责人: Chih-Sheng J Chiang
• 金额: $ 4.73万
• 依托单位: UNIVERSITY OF WISCONSIN-MADISON
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-09-06 至 2016-06-05
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8725603
• 关键词: Ablation; Adopted; Affect; Aftercare; Algorithms; Blood; Blood Flow Velocity; Blood Vessels; Blood Viscosity; Blood flow; Caliber; Cicatrix; Cirrhosis; Clinical; Clinical Trials; Coagulation Process; Complex; Coupling; Data; Deposition; Development; Devices; Diagnostic Neoplasm Staging; Distant; Electrocoagulation; Electromagnetics; Elements; Environment; Event; Excision; Family suidae; Fiber Optics; Goals; Heating; Hemorrhage; Hepatic; High temperature of physical object; Image; Incidence; Injury; Investigation; Kidney; Knowledge; Lead; Life; Link; Liver; Lung; Malignant Neoplasms; Measurement; Methods; Microwave Tumor Ablation; Modality; Modeling; Monitor; Operative Surgical Procedures; Organ; Outcome Study; Patient Care; Patients; Peripheral; Physicians; Portal vein structure; Predisposition; Primary carcinoma of the liver cells; Procedures; Production; Property; Radiofrequency Interstitial Ablation; Reporting; Research Proposals; Risk; Safety; Solid Neoplasm; Source; Staging; Surgical incisions; System; Technology; Temperature; Thermal Ablation Therapy; Thermodynamics; Thrombosis; Time; Tissues; Tumor stage; Update; Validation; Viscosity; Work; X-Ray Computed Tomography; base; clinically relevant; cost; cytotoxic; cytotoxicity; design; effective therapy; hemodynamics; high risk; improved; in vivo; in vivo Model; interest; microwave ablation; microwave electromagnetic radiation; millimeter; minimally invasive; patient population; phantom model; portal vein thrombosis; pressure; programs; radiofrequency; simulation; treatment planning; treatment site; tumor

DESCRIPTION (provided by applicant): Image-guided tumor therapy through thermal ablation is now the predominant choice for treating early-stage solid tumors. Currently, the most popular ablation method is radiofrequency (RF) ablation, which is based on the same principle as electrocautery. However, larger tumors are difficult to treat with RF because of its self- limiting heating mechanism and susceptibility to the cooling effect of nearby vasculature. Recent studies from our lab have shown that microwave ablations are capable of overcoming this "heat-sink" effect and providing a more consistent ablation zone. But the added benefit of better ablative margins comes at the cost of the potential of vascular damage and thrombosis. The aim of this study is to model the heating effects of microwave energy near blood vessels and correlate the damage from these vessels to the risk of thrombosis through a cost function. We will use numerical modeling analysis to perform a parametric study on a heated vessel, isolating the physiologically-relevant range of vessel diameters, blood flow rates and distances from the ablation zone which can lead to cytotoxic heat transfer (Aim 1). We will then validate the simulation results with a phantom vessel model, incorporating clinical components such as real blood and microwave applicators (Aim 2). Lastly, we will perform ablations near vessels using in-vivo models, allowing us to analyze cytotoxic heat transfer in a complex, clinically-relevant environment (Aim 3). Completion of this project will lead to better understanding of coupling electromagnetic analysis with thermal flow, blood viscosity changes in a high-temperature environment and endothelial damage near microwave ablation zones. The goal of this project is to use the data from the three aims to create a thrombotic risk function. This function will allow physicians to safely guide the placement of a microwave ablation applicator to minimize the risk for a thrombotic event. We will primarily using the liver as our organ of interest, but the data we plan to compile will be clinically useful for the ablation of any solid tumor. As with many of our studies in the past, the proposed work is designed to directly influence patient care in tumor ablation programs world-wide.

描述（由申请人提供）：通过热消融进行图像引导的肿瘤治疗现在是治疗早期实体瘤的主要选择。目前，最流行的消融方法是射频（RF）消融，其原理与电灼相同。然而，较大的肿瘤由于其自限性而难以用射频治疗。 加热机制和对附近脉管系统冷却效应的敏感性。我们实验室的最新研究表明，微波消融能够克服这种“散热”效应，并提供更一致的消融区域。但更好的消融边缘的额外好处是以潜在的血管损伤和血栓形成为代价的。本研究的目的是模拟血管附近微波能量的加热效应，并通过成本函数将这些血管的损伤与血栓形成的风险关联起来。我们将使用数值模型分析对加热的血管进行参数研究，隔离血管直径、血流速率和与消融区域的距离的生理相关范围，这些范围可能导致细胞毒性热传递（目标 1）。然后，我们将使用虚拟血管模型验证模拟结果，并结合真实血液和微波涂抹器等临床组件（目标 2）。最后，我们将使用体内模型在血管附近进行消融，使我们能够在复杂的临床相关环境中分析细胞毒性热传递（目标 3）。该项目的完成将有助于更好地理解电磁分析与热流的耦合、高温环境下的血液粘度变化以及微波消融区域附近的内皮损伤。该项目的目标是使用这三个目标的数据来创建血栓风险函数。该功能将使医生能够安全地引导微波消融施用器的放置，以最大限度地降低血栓事件的风险。我们将主要使用肝脏作为我们感兴趣的器官，但是我们的数据 编制的计划将在临床上用于任何实体瘤的消融。与我们过去的许多研究一样，拟议的工作旨在直接影响全球肿瘤消融项目中的患者护理。