Impact of Anode Heel Effect on Testes Dose during Adult Pelvic Radiography

Introduction: Anode heel effect (AHE) referred to attenuation of radiation intensity in the anode side of x-ray tube. This phenomenon is due to angularity of anode which let more attenuation of x-ray photons at the heel of anode than those generated at the cathode side. This variation could affect radiation dose to tissues and organs located at the edge of radiation field such as the testes during pelvic radiography. Therefore, the aim of this study was to investigate the impact of anode heel effect on the testes dose as well as entrance surface dose (ESD) measurement in patients undergoing conventional pelvic radiography.Material and Methods: The studied population included 80 male patients aged from 18 to 55 years who were referred to anteroposterior (AP) projection of conventional pelvic radiography. Patients were divided into two groups. In the 40 patient, feet were positioned toward the anode (FTA) and in 40 other patient, head toward the anode (HTA). The radiation dose measurements were performed using thermoluminescent dosimeters (TLD: LiF: Mg, Cu, P). In order to measure the radiation dose to the testes region, in each patient, three TLDs were placed on the testes region. Moreover, three TLDs were placed at the central point of radiation field on the patients’ pelvis to measure ESD.Results: The radiation dose to the testes was obtained 0.98 mGy and 1.55 mGy in patients with position of FTA and HTA, respectively. Orientating the anode toward the feet was resulted in 36.7% reduction in testes dose. The ESD was obtained 1.44 mGy and 1.39 mGy in patients with position of FTA and HTA, respectively (P<0.05).Conclusion: In pelvic radiography, orienting the anode toward the patients feet would result in lower testes dose. Our results are commensurate with the previous literatures.

Keywords:

anode heel effect , pelvic radiography , testes , dose