Efficiency of Breast Shielding Device in Out-of-Plane Computerized Tomography Imaging of the Abdomen – Preliminary Results

Abstract

SUMMARY The dose absorbed by sensitive breast glandular tissue in abdominal computed tomography examinations, even when the breasts are outside the primary imaging beam, is still significant. Several studies have explored using breast shielding with a protective lead sheet or a bra. Since the source of radiation in computed tomography rotates by 360° around the patient, we made a custom-tailored shielding device that wraps around the entire thorax. The hypothesis is that such a custom-tailored breast shielding device provides significantly better dose reduction. Study participants were female patients with no anatomic anomalies. Entrance surface doses were measured using thermoluminescence dosimeters placed on the skin of the breast in the control group without shielding and on the surface and below the shielding device in the group with anterior shielding and the group with the new device. As expected, according to literature data, doses measured at breast level were above the threshold that epidemiological studies determine as an increased risk of breast cancer development although they were not in the primary imaging plane. Preliminary results of our study showed that average dose reduction was 42% with conventional anterior shielding and 57% with wrapped shielding compared to the doses measured with no shielding.