Determination of Diagnostic Reference Level in routine Computed radiography examination in north of Iran

Introduction: Digital radiography has a major role in nowadays healthcare system so radiation protection (justification and optimization) is important in this field. Many related organizations to protection suggested to establish national and regional diagnostic reference level for medical procedures. Reference levels are typically set at the 75th percentile of the dose distribution from a survey conducted across a broad user base using a special dose measurement protocol and phantom. This study aimed to establish diagnostic reference level for computed radiography examination in north of Iran. Materials and Methods: The data were collected from 7 public hospitals for 12 computed radiographies routine examination including: skull (AP-LAT), cervical (AP-LAT), chest (PA –LAT), thoracic (AP- LAT), lumbar(AP-LAT), abdomen(AP) and pelvis (AP). For each projection, 10 patients at least 18 years olds were investigated. The study was performed by filling out the questioner which was contained the following parameters: Center name, machine manufacturer, Type of Examination, Tube Voltage (kVp), Current Time Product (mAs) and Film Focus Distance (FFD). The quantity of entrance skin dose is evaluated by measuring ESD. The third quartile of ESD related to each projection was considered as DRL of that examination. Results: Based on the data of this study, we expected that diagnostic reference level of computed radiography examination in north of Iran is in accordance with standard values that were suggested by regulatory organizations such as American College of Radiology (ACR)and European Commission (EC). Conclusion: The comparison of the results of this survey with surveys performed in other countries will indicate the protection level of patients in computed radiography examination in north of Iran.