Evaluation of Gonadal Exposure Dose in Long Bone Plain Radiography for Radiation Protection

Introduction: Long bone examination in standing position, as one of the diagnostic methods in plain radiography, is most commonly used in the field of medical diagnosis, especially leg length discrepancy. However, with regard to this examination, reproductive organs are exposed to radiation as they are placed in the adjacent area to the long bone. Due to the sensitivity of gonads to radiation, their exposure must be kept as minimal as possible to the extent to which proper diagnosis is feasible in order to reduce tumor growth in lower extremity examination. The purpose of this study was to optimize the radiation dose in the long bone examination in standing position. Material and Methods: This experimental study was conducted to evaluate the radiation exposure dose to a phantom and estimate effective doses and organ-specific doses (i.e., testes and ovaries) among patients using PC-based Monte Carlo program.  Results: A phantom examination in the posterior-anterior (PA) configuration produced a radiation dose nine and three times smaller than those in the anterior-posterior (AP) and AP with shielding configurations, respectively. In a patient study (PA configuration), the testes, ovaries and effective doses were estimated at 15, 1.2, and 2 times smaller than those in the AP configuration, respectively. Conclusion: This study demonstrated that examinations in the PA configuration produce a smaller radiation dose than those in the AP configuration.