Radiation dose received by the breasts during standard bilateral two view mammography

Abstract

Introduction The breast is one of the main radiation sensitive organs in the human body and it is therefore important to have an accurate assessment of the absorbed dose to this organ and especially to the glandular components. Population screening with mammography is the only intervention proven to reduce mortality from breast cancer through early detection. Mama,ography uses ionizing radiation so any exposure must be justified and doses kept as low as reasonably possible (ALARA principle). Objectives A study to determine the radiation dose received by the breast during standard bilateral two view mammography in Kenyatta National Hospital in Kenya was carried out. Methodology The mean glandular doses (MGDs) of a sample of 60 women were measured. MGD with a standard PMMA phantom was measured as well. The MGDs were calculated according to the Technical Report Series number 457, Dosimetry in Diagnostic Radiology: An International Code of Practice. Results and conclusions The mean MGD for a standard view was 2.67mGy (SO 1.09mGy) and 3.17mGy (SO 1.32mGy) for craniocaudal and mediolateral views respectively. The mean MGO for CC view was lower than that for the MLO view with a high statistical significance (p value = 0.002). This could be explained by the difference in the compressed breast thickness. The mean MGO tor the phantom was 2.47mGy. The bilateral breast thickness was significantly greater for the MLO views (mean 47.71 rnrn) compared to the CC views (mean 42.57 rnm), p value = 0.017. The mean radiation dose received during both CC and MLO views among pre- menopausal women compared to post-menopausal women were not statistically significant.