Bahreyni Toossi Mohammad Taghi, Malekzadeh Malakeh
Medical Physics Research Center, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
Iran J Radiol. 2012 Sep;9(3):145-9. doi: 10.5812/iranjradiol.8065. Epub 2012 Sep 17.
With the increase of X-ray use for medical diagnostic purposes, knowing the given doses is necessary in patients for comparison with reference levels. The concept of reference doses or diagnostic reference levels (DRLs) has been developed as a practical aid in the optimization of patient protection in diagnostic radiology.
To assess the radiation doses to neonates from diagnostic radiography (chest and abdomen). This study has been carried out in the neonatal intensive care unit of a province in Iran.
Entrance surface dose (ESD) was measured directly with thermoluminescent dosimeters (TLDs). The population included 195 neonates admitted for a diagnostic radiography, in eight NICUs of different hospital types.
The mean ESD for chest and abdomen examinations were 76.3 µGy and 61.5 µGy, respectively. DRLs for neonate in NICUs of the province were 88 µGy for chest and 98 µGy for abdomen examinations that were slightly higher than other studies. Risk of death due to radiation cancer incidence of abdomens examination was equal to 1.88 × 10 (-6) for male and 4.43 × 10 (-6) for female. For chest X-ray, it was equal to 2.54 × 10 (-6) for male and 1.17 × 10 (-5) for female patients.
DRLs for neonates in our province were slightly higher than values reported by other studies such as European national diagnostic reference levels and the NRPB reference dose. The main reason was related to using a high mAs and a low kVp applied in most departments and also a low focus film distance (FFD). Probably lack of collimation also affected some exams in the NICUs.
随着用于医学诊断目的的X射线使用量增加，了解患者所接受的剂量对于与参考水平进行比较很有必要。参考剂量或诊断参考水平（DRLs）的概念已被提出，作为优化放射诊断中患者防护的实用辅助手段。
评估新生儿诊断性X线摄影（胸部和腹部）的辐射剂量。本研究在伊朗某省的新生儿重症监护病房进行。
使用热释光剂量计（TLDs）直接测量体表入射剂量（ESD）。研究对象包括在不同医院类型的8个新生儿重症监护病房接受诊断性X线摄影的195名新生儿。
胸部和腹部检查的平均ESD分别为76.3微戈瑞和61.5微戈瑞。该省新生儿重症监护病房新生儿胸部检查的DRLs为88微戈瑞，腹部检查为98微戈瑞，略高于其他研究。腹部检查因辐射致癌的男性死亡风险为1.88×10（-6），女性为4.43×10（-6）。对于胸部X线检查，男性患者为2.54×10（-6），女性患者为1.17×10（-5）。
我省新生儿的DRLs略高于其他研究报告的值，如欧洲国家诊断参考水平和英国国家辐射防护委员会参考剂量。主要原因与大多数科室使用高毫安秒和低千伏以及低焦片距（FFD）有关，新生儿重症监护病房可能缺乏准直也影响了一些检查。
