PDF(Pubmed)
Abstract：
We quantified the level of backscatter radiation generated from physicians\' heads using a phantom. We also evaluated the shielding rate of the protective eyewear and optimal placement of the eye-dedicated dosimeter (skin surface or behind the Pb-eyewear). We performed diagnostic X-rays of two head phantoms: Styrofoam (negligible backscatter radiation) and anthropomorphic (included backscatter radiation). Radiophotoluminescence glass dosimeters were used to measure the eye-lens dose, with or without 0.07-mm Pb-equivalent protective eyewear. We used tube voltages of 50, 65 and 80 kV because the scattered radiation has a lower mean energy than the primary X-ray beam. The backscatter radiation accounted for 17.3-22.3% of the eye-lens dose, with the percentage increasing with increasing tube voltage. Furthermore, the shielding rate of the protective eyewear was overestimated, and the eye-lens dose was underestimated when the eye-dedicated dosimeter was placed behind the protective eyewear. We quantified the backscatter radiation generated from physicians\' heads. To account for the effect of backscatter radiation, an anthropomorphic, rather than Styrofoam, phantom should be used. Close contact of the dosimeter with the skin surface is essential for accurate evaluation of backscatter radiation from physician\'s own heads. To assess the eye-lens dose accurately, the dosimeter should be placed near the eye. If the dosimeter is placed behind the lens of the protective eyewear, we recommend using a backscatter radiation calibration factor of 1.2-1.3.
摘要：
我们使用体模量化了医生头部产生的反向散射辐射水平。我们还评估了防护眼镜的屏蔽率和眼睛专用剂量计的最佳放置（皮肤表面或铅眼镜后面）。我们对两个头部体模进行了诊断X射线：聚苯乙烯泡沫塑料（可忽略的反向散射辐射）和拟人化（包括反向散射辐射）。放射性光致发光玻璃剂量计用于测量眼晶状体剂量，带或不带0.07-mmPb等效防护眼镜。我们使用50、65和80kV的管电压，因为散射辐射的平均能量低于初级X射线束。反向散射辐射占眼晶状体剂量的17.3-22.3%，百分比随着管电压的增加而增加。此外，防护眼镜的屏蔽率被高估了，当眼睛专用剂量计被放置在防护眼镜后面时，眼睛晶状体的剂量被低估了。我们量化了医生头部产生的反向散射辐射。为了解释反向散射辐射的影响，一个拟人化的人,而不是聚苯乙烯泡沫塑料，应该使用幻影。剂量计与皮肤表面的紧密接触对于准确评估医生自身头部的反向散射辐射至关重要。为了准确评估眼晶状体剂量，剂量计应放在眼睛附近。如果剂量计放在防护眼镜镜片后面,我们建议使用1.2-1.3的反向散射辐射校准因子。
