| 摘要: | 強度調控放射治療(intensity modulated radiation therapy, IMRT)是目前除了手術之外，最常用來治療癌症的方法之一。IMRT是由電腦治療計畫系統來動態控制多葉片準直儀(multileaf collimator, MLC)，以調控放射線射束的強度分布。而這樣的輻射醫療品質是受到行政院原子能委員會所公告的「輻射醫療暴露品質保證標準」的規範，而所需校驗項目繁多（如輻射強度對應比例驗證、輻射強度分佈差異驗證、射束平坦度評估、及直線加速器定期輸出品質確認），且因其變異性又可分為每日、每月及每年校驗。但往往因為這些校驗的程序都需要額外的設備，並缺乏適當的分析軟體。因此，本研究希望使用治療過程中由電子式影像擷取系統(electronic portal imaging device, EPID)所取得的影像資料來進行分析，以完成所需校驗的工作。利用影像處理技術在每次的治療過程中進行各項的校驗工作，可簡化原先的校驗流程並提高校驗的效率。
The intensity modulated radiation therapy (IMRT) is the most used treatment for cancer excepting surgery. IMRT uses the multuleaf collimater (MLC), which is dynamical controlled by the computerized treatment plan system, to adjust the intensity distribution of the radiation beams. However, the quality of radiological medicine is specified by the “radiation medical exposure quality assurance rules” of Atomic Energy Council. Under the quality assurance rules, there are many items, such as radiation intensity correspondence proportion confirmation, radiation intensity distribution difference confirmation, beam flatness evaluation, and linear accelerator regular output quality assurance, should be calibrated in daily, monthly and annually routines. In addition, it is difficult to run these calibration procedures well due to need for many extra calibration equipments and lack of suitable software. In this study, the images, obtained by electronic portal imaging device (EPID) during treatment process, are used to analyze the calibration items indeed. By using the image processing technology, the calibration procedures for each treatment will be more simplified and effective than the traditional calibration processes |
