Yakoumakis E, Dimitriadis A, Makri T, Karlatira M, Karavasilis E, Gialousis G
Medical Physics Department, Medical School, University of Athens, 75 Mikras Asias Str. Goudi 11527, Athens, Greece.
Radiat Prot Dosimetry. 2013 Dec;157(3):355-62. doi: 10.1093/rpd/nct150. Epub 2013 Jun 13.
The estimation of the radiological risk in the case of children is of particular importance due to their enhanced radiosensitivity when compared with that of adult patients. The purpose of this study is to estimate the organ and effective doses of paediatric patients undergoing micturating cystourethrography examinations. Since direct measurements of the dose in each organ are very difficult, dose-area products of 90 patients undergoing cystourethrography examinations were recorded and used with two Monte Carlo codes, MCNP5 and PCXMC2.0, to assess the organ doses in these procedures. The organs receiving the highest radiation doses were the urinary bladder (ranging from 1.9 mSv in the newborn to 4.7 mSv in a 5-y old patient) and the large intestines (ranging from 1.5 mSv in the newborn to 3.1 mSv in the 5-y old patient). For all ages the main contributors to the total organ or effective doses are the fluoroscopy projections compared with the radiographs. There was a reasonable agreement between the dose estimates provided by PCXMC v2.0 and MCNP5 for most of the organs considered in this study. In special cases, there were systematic disagreements in organ doses such as in the skeleton, gonads and oesophagus due to the anatomical differences between patient anatomic models employed by the two codes.
由于儿童相较于成年患者具有更高的辐射敏感性，因此评估儿童的放射风险尤为重要。本研究的目的是估算接受排尿性膀胱尿道造影检查的儿科患者的器官剂量和有效剂量。由于直接测量每个器官的剂量非常困难，因此记录了90例接受膀胱尿道造影检查患者的剂量面积乘积，并使用两个蒙特卡罗代码MCNP5和PCXMC2.0来评估这些检查过程中的器官剂量。接受最高辐射剂量的器官是膀胱（新生儿为1.9毫希弗，5岁患者为4.7毫希弗）和大肠（新生儿为1.5毫希弗，5岁患者为3.1毫希弗）。对于所有年龄段，与X光片相比，透视投影是器官总剂量或有效剂量的主要贡献者。在本研究中考虑的大多数器官中，PCXMC v2.0和MCNP5提供的剂量估计之间存在合理的一致性。在特殊情况下，由于两个代码所采用的患者解剖模型之间的解剖差异，在骨骼、性腺和食管等器官剂量方面存在系统性差异。
