整合三維定位移動平台系統與超音波系統及MRI影像系統應用於熱治療

Abstract

磁振造影導引高能量聚焦超音波(MRIgHIFU)熱治療的發展潛力可由國內外各大研究機構及公司投入開發的程度可知，其非侵入性的治療以及手術時間短，是該技術在臨床治療上的優點。本研究目標是整合三維定位移動平台系統、超音波換能器系統以及MRI影像系統，以便應用於熱治療。 本研究使用LabVIEW做為系統整合開發平台，主架構為一套三維定位移動平台來載送超音波換能器做腫瘤熱治療，並結合1.5T MR影像來做導引、治療規劃及治療監控，而換能器的選擇可依患部位置及大小做靈活搭配。使用者可以從主控電腦來控制平台的移動、超音波能量輸出的大小及持續輸出時間以及監控MRI溫度影像。 測試結果顯示，超音波系統對輸出時間的控制誤差少於0.1秒，而對燒灼區域的控制誤差在3mm左右，MRI溫度影像部分，雖能夠與國衛院開發的程式有相似的結果，但若採用較多干擾的原始影像會有較高的誤差產生。 本研究完成了三維定位移動平台系統、超音波加熱系統及MRI影像系統的整合，在實驗室環境下及MR環境下能有效運作，但還須克服MRI溫度影像的準確度以及解決造成MR影像雜訊的來源。

The potential of Magnetic Resonance Imaging guided High Intensity Focused Ultrasound (MRIgHIFU) thermal therapy was well-known through domestic and foreign research institutions and companies. Non-invasive treatment and short treatment period for each lesion are the technical advantages of MRIgHIFU for clinical treatment. The purpose of this study is to integrate a three-dimensional positioning system, focused ultrasound system and MRI imaging system for MRIgHIFU thermal therapy. In this study, LabVIEW development environment was used for system integration. The main structure is a three-dimensional positioning system to load ultrasound transducer to perform thermal therapy. This system was combined with a 1.5-T MRI to guide transducer movement, to plan and to monitor the treatment. A suitable transducer can be chosen for the tumor location and size. User can control the movement of the positioning system, ultrasound output power, ultrasound sonication time and observe the MRI temperature mapping via the host computer. The results show that the time error of ultrasound system output control is less than 0.1 s, and the position error of ablation region is around 3 mm. The MRI temperature mapping for the developed program has similar results as that of National Health Research Institute while conversion of the raw data with more interference may produce a higher error. In this study, the integration of three-dimensional positioning system, ultrasound heating system and MRI imaging system was completed. This system can operate properly under the laboratory conditions and the MR environment. However, the cause of MR image noise must be overcome to obtain a better accuracy of MR temperature mapping.