Investigation of Scattered Radiation Reduction Effect by Use of Collimator Cover Covered with Leaded Sheet in Angiography Equipment

Abstract

The purpose of this study was to investigate the effect of scattered radiation reduction to medical staff by attaching the leaded sheet on the collimator cover of the angiography equipment. Ambient dose equivalent was measured to compare the rate of scattered radiation reduction between with and without the leaded sheet. Shielding effect was confirmed for scattered radiation in all directions, especially 27% of shielding ratio in the head and neck area when angiography equipment installed with small detector, and more than 40% of shielding ratio when adjusting a cut portion of leaded sheet to the field size. However, it decreased when the dose area product meter was not attached. Therefore, our proposed leaded sheet can reduce radiation dose to medical staff during angiographic and interventional procedures.

Technical Note: Assessment of scatter originating from the x‐ray tube collimator assembly of modern angiography systems

“…Similar to the work of Miyagawa et al, this work investigated the efficacy of a lead sheet secured to the collimator assembly cover . By comparing this work, Miyagawa et al used a block PMMA scatter phantom and measured total scatter to an ionization chamber positioned to mimic the location of a performing physician.…”

“…Similar to the work of Miyagawa et al, this work investigated the efficacy of a lead sheet secured to the collimator assembly cover. 13 By comparing this work, Miyagawa et al used a block PMMA scatter phantom and measured total scatter to an ionization chamber positioned to mimic the location of a performing physician. They measured scatter at three elevations (40, 80, and 130 cm from the floor), at four positions around the patient table, and using five different projection angles, but did not specifically isolate scatter originating from within the phantom vs the collimator assembly.…”

“…However, that work did not include a physical KAP meter. In 2017, Miyagawa et al investigated a lead‐lined collimator assembly cover as a means to reduce scattered radiation to the operator from modern x‐ray angiography systems . However, as evidenced from literature, there has not been widespread recognition of the potential contribution of scatter originating from the collimator assembly to occupational radiation dose.…”

“…In 2017, Miyagawa et al investigated a lead-lined collimator assembly cover as a means to reduce scattered radiation to the operator from modern x-ray angiography systems. 13 However, as evidenced from literature, there has not been widespread recognition of the potential contribution of scatter originating from the collimator assembly to occupational radiation dose. Neither the International Commission on Radiological Protection (ICRP), 7,14 National Council on Radiation Protection and Measurements (NCRP), 15 nor the International Electrotechnical Commission (IEC) 16 specifically recognizes the collimator assembly as a source of scatter radiation.…”