在放射治療中，病患臨床接受劑量的驗證工作，是品質保證中重要的一環。而活體劑量度量（in vivo dosimetry）乃是一種簡單而又準確的驗證方式，它是在病患治療時即時確認的唯一方法，且它獨立於劑量計算系統之外，並可同時追蹤數個誤差。因此，活體劑量度量已逐漸形成為品質保證中之基本項目。
本研究使用金屬氧化半導體場效電晶體（metal oxide semiconductor field effect transistor, MOSFET）針對頭頸部、左右對照、深度相同之放射治療病患，進行活體劑量度量。將MOSFET劑量計置於入射及出射之皮膚表面，可測得入射劑量（entrance dose）及出射劑量（exit dose），兩者透過平均法或穿透率曲線法即可獲得病患體內之腫瘤劑量，推算之腫瘤劑量與醫囑之處方劑量比較，並追蹤其誤差來源。
研究結果共量測了32個照野，屬於10位病患，結果有40.625％照野的腫瘤劑量大於5 ％之處方劑量，大於10 ％的劑量誤差則有9.375 ％。檢討整個治療流程，系統誤差可能來自於組織密度不均質（inhomogeneity）與頭部面罩之影響。除此之外，MOSFET劑量計之不穩定性，可能來自於其計讀系統，若操作不當其讀值將有明顯差異，因此也造成活體量測之不確定性。
經由本研究可建立一套包括校正劑量計、修正各治療條件、與實際病患量測之完整活體劑量驗證方式，而使用MOSFET劑量計做為臨床輻射度量有多項優點，包括體積小、簡單的校正程序、同步計讀、和反應之再現性佳等。也經由誤差分析，瞭解治療流程中可能發生誤差之程序，在決定治療計畫時應特別注意，以避免劑量誤差，達到品質保證之目的。

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