Choudhary Neha, Rana Bhupendra Singh, Shukla Arvind, Oinam Arun Singh, Singh Narinder Paul, Kumar Sanjeev
Department of Radiotherapy, Shanti Mukand Hospita, New Delhi, India.
Department of Radiodiagnosis, PGIMER, Chandigarh, India.
Radiat Prot Dosimetry. 2019 Aug 1;184(2):256-262. doi: 10.1093/rpd/ncy207.
The present work reports data of radiation exposure to the patients during head, chest, pelvis and abdomen CT examinations performed on a third-generation 16-slice CT machine. Radiation exposure was estimated using size specific dose estimates (SSDE) method, which takes into account patient's physical dimensions in phantom measured computed tomography dose index (CTDI) value. The reported median CT dose volume index CTDIvol values in head, chest, pelvis and abdomen examinations were 26.76, 16.27, 29.81 and 14.74 mGy, respectively. The median doses evaluated using SSDE methodology for the above mentioned procedure were 54.1, 23.1, 42.8 and 20.1 mGy, respectively. Our results showed variation in dose values estimated using CTDI and SSDE methods in all examinations. The evaluated SSDE values were also compared to the values derived from data reported by the American Association of Physicist in Medicine (AAPM). SSDE values in present measurements are 4-8% lower than AAPM values. The present results show that CTDI parameters recorded on CT console should not be used to specify patient dose during CT procedures.
本研究报告了在第三代16层CT机上对患者进行头部、胸部、骨盆和腹部CT检查期间的辐射暴露数据。使用尺寸特异性剂量估计（SSDE）方法估算辐射暴露，该方法在体模测量的计算机断层扫描剂量指数（CTDI）值中考虑了患者的身体尺寸。报告的头部、胸部、骨盆和腹部检查中CT剂量体积指数CTDIvol的中位数分别为26.76、16.27、29.81和14.74 mGy。使用SSDE方法对上述检查评估的中位数剂量分别为54.1、23.1、42.8和20.1 mGy。我们的结果表明，在所有检查中，使用CTDI和SSDE方法估算的剂量值存在差异。还将评估的SSDE值与美国医学物理学家协会（AAPM）报告的数据得出的值进行了比较。本次测量中的SSDE值比AAPM值低4-8%。目前的结果表明，CT操作过程中，CT控制台上记录的CTDI参数不应用于指定患者剂量。
