Abstract

Background: Although the risk of radiographic imaging is negligible compared to its benefits, the overall risk to the population is significant due to a large number of these examinations. Therefore, this study was designed to estimate entrance surface air kerma (ESAK) and provide diagnostic reference level (DRL) in routine radiological examinations. Methods: In this study 783 patients were involved who had a mean age of 41 +/- 14 years. The study included five routine radiological examinations; lumbar vertebrae, pelvis, abdomen, chest, and skull from 11 radiology devices located in Yazd province. The ESAK was estimated for each examination, and then the DRL values as the third quartile of the distribution of the ESAK median values were calculated. The effective dose and risk of exposureinduced death (REID) were also estimated using PCXMC (a personal computer-based Monte Carlo) software. Results: The DRL values for the investigated examinations were obtained as: abdomen (anterior-posterior AP): 3.57, chest (AP): 1.23, chest (lateral LAT): 1.12, chest (posterior-anterior PA): 0.48, lumbar vertebrae (AP): 4.16, lumbar vertebrae (LAT): 8.81, lumbar vertebrae (oblique OB): 10.33, pelvis (AP): 2.77, pelvis (LAT): 2.82, skull (AP): 2.34, skull (LAT): 1.39, and skull (PA): 2.03 mGy. The lumbar vertebrae (OB) radiology examination had the highest effective dose (1.03 +/- 0.76 mSv). In addition, the highest REID value in lumbar examination was associated to stomach cancer (7.03 +/- 6.11 deaths per million). Conclusion: Based on the results, although the DRL values were not higher than those of the international organizations' levels, they can be reduced by adequate training of radiographers.