比較凝膠劑量計與EBT3膠片評量臨床放射治療的劑量驗證

Comparison of Gel Dosimeters and EBT3 Film to Evaluate the Dose Verification of Clinical Radiotherapy

黃振義(Jen-I Hwang) ； 楊子慶(Tzu-Chin Yang) ； 黃琮傑(Tsung-Chieh Huang) ； 謝玲鈴(Ling-Ling Hsieh)

《台灣應用輻射與同位素雜誌》 17卷1期 (2021/03) Pp. 2053-2059

摘要

對於癌症病患，放射治療計畫在執行前或期間，必須驗證所給予的劑量是否正確，本研究以N-isopropylacrylamide （NIPAM）凝膠劑量計及輻射變色軟片（EBT3 film）量測放射治療患者的IMRT治療計畫之照射劑量，進行劑量驗證並相互比較。比較照射後的EBT3膠片及NIPAM凝膠劑量計，二維（two dimensions, 2D）的等劑量曲線圖（Isodose curve）及3％／3 mm的伽馬通過率。研究結果顯示，在≥70％的劑量區間，NIPAM凝膠劑量計的評估結果與EBT3膠片相近，而在＜70％的劑量區間，NIPAM凝膠劑量計的評估結果皆優於EBT3膠片。另外，NIPAM凝膠的伽馬通過率96.969％也明顯比EBT3膠片的57.599％高出許多。由本研究結果可證明，NIPAM聚合物凝膠劑量計具有高準確度，是一種很適合用於臨床放射治療劑量驗證的工具。

關鍵字

NIPAM ； EBT3膠片 ； 伽馬評估

並列摘要

Prior and during cancer treatment for the execution of radiotherapy plan, it is essential for the physicist to quantify the dosage of the radiation. This study measured the absorbed dose of clinical patient Intensity Modulated Radiation Therapy (IMRT) using the N-isopropylacrylamide (NIPAM) gel dosimeter and EBT3 film technique. Post irradiated NIPAM gels results were compared with measurement results obtained using EBT3 films. Both dosimeters were evaluated using an isodose curve and 2D gamma evaluation with the criteria of 3% dose and 3 mm DTA. The results obtained using the NIPAM gel dosimeter and films were highly consistent for the ≥70% dose region. However, the film measurements and treatment planning system-calculated distribution were different at the low-dose region (＜70%). The gamma passing rate of the NIPAM gel was 96.969%, which was higher than that of the film (57.599%). Therefore, NIPAM gel can serve as tool for verification of dose distribution during clinical radiation treatment.

並列關鍵字

NIPAM Gel ； EBT3 Film ； Gamma Evaluation

參考文獻

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