Abstract

The purpose of this study is to develop a method for use at extremely low-dose ranges and to decrease the uncertainty outside the recommended range of Gafchromic RTQA2 (RTQA2). By this method, the CT dose including the scattered radiation region can be grasped. The base density was increased by ultraviolet (UV)-ray preirradiation. RTQA2 was irradiated with UV-A rays for 26 and 40 h. Subsequently, RTQA2 was exposed to 2, 4, 6, 8, 10, 25, 50, 75, 100, 150, 200 and 250 mGy X-rays using a segmentation method. Calibration curves with and without UV-A irradiation were compared. The calibration curve with 40-h UV-A ray irradiation was the most linear, and a steeper slope area was not observed. The uncertainty in the calibration curve was reduced (p < 0.05). UV-A ray irradiation is an effective method for treating RTQA2; the accuracy in the extremely low-dose range of RTQA2 was improved.

中文翻译：

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使用紫外线预辐照来提高使用 GAFCHROMIC RTQA2 薄膜的 CT 低剂量测量的准确性

摘要

本研究的目的是开发一种在极低剂量范围内使用的方法，并降低 Gafchromic RTQA2 (RTQA2) 推荐范围之外的不确定性。通过该方法，可以掌握包括散射辐射区域的CT剂量。通过紫外线 (UV) 射线预照射增加了碱密度。RTQA2 用 UV-A 射线照射 26 和 40 小时。随后，RTQA2 使用分割方法暴露于 2、4、6、8、10、25、50、75、100、150、200 和 250 mGy X 射线。比较了有和没有 UV-A 照射的校准曲线。40 h UV-A 射线照射的校准曲线最线性，未观察到更陡峭的斜率区域。校准曲线的不确定度降低 ( p < 0.05)。UV-A射线照射是治疗RTQA2的有效方法；提高了 RTQA2 在极低剂量范围内的准确性。