Design of Tracking System with Respiratory Flow Measurement n High Intensity Focused Ultrasound Liver Tumor Treatment

In the research of treating tumors, High Intensity Focused Ultrasound (HIFU) is one of the popular treatment methods in the recent years. The treatment in the moving tumor is always a serious problem. A number of methods can solve this in the radiotherapy. Comparing Real-Time Radiotherapy Tracking System (RTRT), there is not a nicer HIFU tracking treatment system so NTU MRI Guided HIFU Tracking System was developed before. A Magnetic Resonance Imaging (MRI) system guides HIFU in this system. In order to solve the delay time produced in the liver position determination system, the neural network is a predictor. The predicted position is used to control the position of the ultrasound transducer. Some tracking errors always exist in NTU MRI Guided HIFU Tracking System and therefore the performance is not good enough. It is the reason to improve HIFU tracking system.n order to get a better performance, a respiration signal measurement system replaced MRI system and a mapping system replaced the liver position determination system. The mapping system is used to transform the respiration signal into the liver position. The system is called NTU Respiration Signal Based HIFU Tracking System. A higher sampling rate of getting liver positions is in this system. The tracking error of this system is lower than the tracking error of NTU MRI Guided HIFU Tracking System. The performance of NTU Respiration Signal Based HIFU Tracking System is also better. Some comparisons verify the new design can bring the improvement in the performance of tracking.