Shielding Performance and Clinical Applicability of Lead-Free Radiation Shielding Materials for Computed Tomography Imaging

Owing to the high radiation exposure engendered by computed tomography (CT) examinations and image quality degradation of conventional radiation shielding materials. This study evaluated radiation attenuation performance and image quality maintenance potential of a newly developed lead-free composite shielding material for use in CT examinations. This material was composed of bismuth, tungsten, tungsten carbide, aluminum, and polyurethane, and its shielding performance, lead equivalence, and scattered radiation effects were evaluated. Signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and changes in tube current-time product (mAs) automatically adjusted by the automatic exposure control (AEC) system were analyzed according to the presence/absence of the shielding material across regions. For the clinical study, CT scans were performed on four patients. Furthermore, the images were reviewed to evaluate whether this material affected image quality. The shielding material exhibited radiation reduction levels comparable to those reported in previous studies. SNR and CNR analyses revealed some noise-related differences, without significance. Owing to AEC, the use of the shielding material engendered a slight reduction in mAs values. No artifacts or meaningful differences were observed in image quality. The composite material addressed the limitations of conventional shields. Thus, it has clinical application in diagnostic CT to reduce patient radiation exposure.