1. Research Background The background of this study centers on stereotactic body radiation therapy (SBRT), an advanced form of radiotherapy that is short in duration, highly effective, and easy for patients to comply with. However, even small breathing movements can reduce its precision. Abdominal compression devices have been proven to reduce respiratory motion and are now widely used in clinical practice. This study aims to determine whether a novel abdominal compression positioning technique can control tumor motion as effectively as current abdominal compression devices, whether it works better than traditional thermoplastic masks, and whether it can offer meaningful benefits to patients undergoing radiotherapy. These questions remain to be explored.
2. Study Objectives The purpose of this study is to investigate how different immobilization devices affect the respiratory motion of liver tumors, in order to better assist with target delineation and the delivery of stereotactic body radiation therapy.