Local-Reference Patient Dose Evaluation in Conventional Radiography Examinations in Mazandaran, Iran

BACKGROUND The most efficient application of ionizing radiation is serving medical purposes and using this radiation has caused people to learn that artificial sources of radiation exposure among these resources can be of highest exposure rate. OBIECTIVE The present study is aimed at initially establishing a baseline for local-reference dose level in Mazandaran, Iran in 12 projections of the most conventional x-ray examination. METHODS In this study, 13 public hospitals in Mazandaran province were selected for review and required data collected for ten adult patients with mean weight of 70±10kg in each projection. Then, information of each center was separately analyzed. Next, in order to measure x-ray output tube, the dosimeter RTI model Barracuda calibrated has been applied for measuring air karma within energy rage of 40-150kvp. ESAK and ESD parameters, usually used for monitoring DRL in conventional radiography, were calculated. RESULTS Mean ESDs in this study has been obtained to 1.47±0.98 for skull (PA/AP), 1.01±0.79 for skull (LAT), 0.67±0.38 for cervical spine (AP), 0.79±0.37 for cervical (LAT), 0.49±0.38 for chest (PA/AP), 1.06±0.44 for chest (LAT), 2.15±0.73 for thoracic spine (AP), 3±0.87 for thoracic spine (LAT), 2.81 ±0.82 for lumbar spine (AP), 4.28±0.78 for lumbar (LAT), 2.07±1.17 for abdomen and 1.90±0.99 for pelvis, respectively. The ESDs calculated for chest examination in both projections, PA and LAT are more than values recommended by the UK (2000), Brazil and Slovenia. CONCLUSION The present study has determined wide variations in radiation dose of x-ray examinations among hospitals in Mazandaran, Iran. In order to reduce skin dose, an optimization procedure should be considered. Application of a reference dose (DRL) could be a practical method for this purpose. The role of optimization of radiography parameters for reducing patient dose is a significant issue. Through optimizing parameters, it would be possible to preserve image quality while reduction of patient dose.