常規X光攝影輻射劑量評估

Radiation Dose Evaluation of Routine X-ray

張仕明(Shih-Ming Chang) ； 史天宇(Tian-Yu Shih) ； 鄭凱元(Kai-Yuan Cheng) ； 陳佳惠(Chia-Hui Chen)

《中華放射線技術學雜誌》 44卷4期 (2020/12) Pp. 202-209

摘要

放射診斷影像具有輻射曝露的包含了常規X光、透視攝影、乳房攝影、電腦斷層掃描，近年來人們越來越關注輻射對人體的潛在危害，並尋求有效降低輻射曝露劑量的方法。常規X光在臨床醫學是使用最頻繁的檢查，由於檢查時間短暫而且單次輻射暴露劑量不高，受檢者與檢查者往往不會產生防護的意識，所以曝露劑量與影像品質的控制往往最容易被忽略掉。本次研究利用MOSFET計讀儀對成人擬人假體之頭部、胸部立姿、胸部臥姿、腹部與腰椎側面的常規X光檢查，進行眼球水晶體、甲狀腺、乳腺、肝臟與性腺之曝露劑量評估。結果顯示單一X光機因應CR與DR的設定條件不同，產生之曝露劑量會產生差異；DR的條件低於CR，重要器官最大曝露劑量眼球水晶體最高為0.181 ± 0.011 cGy，甲狀腺最高曝露劑量為0.098 ± 0.009 cGy，乳腺最高曝露劑量為0.087 ± 0.002 cGy，肝臟獲得最高的劑量為0.064 ± 0.005 cGy，性腺獲得較高的曝露劑量0.195±0.004μGy。依照游離防護安全標準，一般大眾一年內之有效等效劑量不得超過1 mSv，本研究顯示常規X光檢查的有效等效劑量最大為0.462 mSv。常規X光檢查會造成全身器官微量的輻射暴露，所接受之曝露劑量仍明顯低於臺灣每人每年輻射劑量之限制。

關鍵字

常規X光檢查 ； 曝露劑量 ； 器官

並列摘要

Radiation diagnostic imaging with radiation exposure includes routine X-ray, fluoroscopy, mammography, and computed tomography. In recent years, people have become more concerned about the potential hazards of radiation exposure, and search the methods to reduce the exposure dose. Routine X-ray is the most frequently used exam in clinical. Because of the examination time is short and radiation exposure dose is low at the one time, which causes the awareness of protection. So, those radiation exposure dose and image qualities are often easy to be ignored. An anthropomorphic phantom was taking routine X-ray protocol of head, chest standing, chest supine, abdomen and L-spine lateral . The exposure dose assessment of the lens of the eye, thyroid, breast, liver and gonads was performed by using MOSFET (metal oxide semiconductor field effect transistor) dosimeters. The results showed maximum exposure dose was 0.181 ± 0.011 cGy lens of the eye, and there were 0.098 ± 0.009 cGy, 0.087 ± 0.002 cGy in the thyroid and breast, respectively. Liver was 0.064 ± 0.005 cGy, and the gonads were 0.195 ± 0.004 cGy. According to Taiwan's regulations＂ Safety Standards for Protection against Ionizing Radiation＂, set at 1 mSv per year maximum admissible effective dose resulting from human activities outside the natural radioactivity and expositions for medical reasons. This study shows that the maximum effective equivalent dose of conventional X-ray examination is 0.462 mSv. Routine X-ray examinations can cause small amount of radiation exposure to the whole body organs. The exposure dose received is still significantly lower than the annual radiation dose limit of Taiwanese.

並列關鍵字

routine X-ray ； exposure dose ； organ