Reduction of scattered radiation dose by X-ray shielding during mammography

Abstract

Scattered X-rays during mammography can cause undesired increased exposure to radiation during the generation of medical images, which could cause cancer because the breast is highly sensitive to radiation. Hence, to prevent indirect radiation to the contralateral breast tissue from scattered X-rays, a lead acrylic plate has been developed that can be placed between the two breasts during mammography procedures. However, there is a lack of studies assessing the reduction in the exposure dose to the breast using shielding tools, which would consequently reduce radiation to the surrounding organs during mammography. Thus, this study aimed to evaluate the usefulness of the breast shield for mammography, and the average glandular dose (AGD) was measured during craniocaudal (CC) projection mammography. The spatial dose, calculated as the distance from the imaging center in the direction of the contralateral breast; the surface dose, assessed using a thermoluminescence dosimeter (TLD) at the 5 points; and the exposure dose in the contralateral breast in the breast phantom were measured with and without the use of the shield. The measured AGD was 1.6 mGy, and the spatial dose from the imaging center and the surface dose to the contralateral breast were reduced by ~97% and ~93%, respectively, with X-ray shield use. Thus, the study outcomes suggest that using an inter-breast X-ray shield during mammography can effectively reduce indirect radiation from scattered X-rays to the contralateral breast tissue.