Design and Optimization of Microwave Ablation Tools and Techniques.

摘要

Thermal ablation is a minimally-invasive procedure that is used as an alternative to surgical resection in treating early-stage solid tumors. Due to its percutaneous route of administration, thermal ablations have been shown to be associated with less bleeding, fewer complications and quicker recovery compared to surgery. While radiofrequency ablation (RFA) is currently the most common heating modality used for ablation, microwave ablations have rapidly gained traction in academic centers in recent years due to its improved heating physics. Microwave offers substantial benefits over radiofrequency ablation through faster heat generation, leading to larger and more homogenous ablation zones in highly-perfused tissue. These qualities can lead to better margins during tumor ablation and a smaller chance for tumor recurrence. However, controlling the high power and temperatures associated with microwave has remained a formidable barrier toward widespread clinical adoption. The tools used in microwave ablation, especially the antenna itself, require modifications in order to decrease shaft heating. The physics of microwave heating, which now incorporate water vaporization, needs to be accounted for in the tissue heating process. Lastly, the role of hotter ablation zones in thrombosing larger blood vessels is becoming a growing concern for physicians. This thesis aims to further our understanding of these issues.