Document Type : Original Research


1 Student Research Committee, School of Paramedical Sciences, Zanjan University of Medical Sciences, Zanjan, Iran

2 Department of Biomedical Physics and Engineering, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran

3 Department of Radiology, Mousavi Hospital, School of Medicine, Zanjan University of Medical Sciences, Zanjan, Iran

4 Department of Radiology, School of Paramedical Sciences, Zanjan University of Medical Sciences, Zanjan, Iran



Background: Numerous Computed Tomography (CT) scan requests for trauma patients have raised serious concern about the impacts of radiation such as radiation-induced cancers.
Objective: This study aimed to evaluate the necessity rate of requested head CT scans for traumatic patients and to ultimately estimate the risk of radiation-induced brain cancer.
Material and Methods: In this retrospective analytical study, traumatic patients, who had undergone a head CT scan in a two-month period from August 23 to October 22, 2018, were considered as the study population. Two radiologists reviewed each patient individually to evaluate the rate of normal and abnormal cases. Dose length product in milligrays (mGy) was utilized to calculate the effective dose (ED) in millisieverts (mSv), resulting in an assessment of the risk of radiation-induced brain cancer using ICRP 103.
Results: Among 523 scans, 460 patients (88%) received normal reviews, while only 47 patients (9%) had findings related to their current trauma. The mean effective dose value was 1.05±0.36 mSv. Risk of the radiation induced brain cancer was calculated to be 0.037 and 0.030 new cancer cases in 10000 males and females per Gy, respectively. 
Conclusion: Final results demonstrated that a significant number of traumatic patients undergoing a CT scan are in fact, healthy. Such reckless usage of CT and consequently the excess exposure could result in a dramatic rise in cancer rates. The need to limit unnecessary CT scan usage and keeping the radiation given to patients as low as reasonably achievable (ALARA) when collecting essential diagnostic data is more critical than ever.


Hadi Moradi (Google Scholar)

Hamed Rezaeejam (Google Scholar)


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