Non-lead flexible composite shields efficiency in decreasing dose in chest CT scan imaging

Lead-based radiation shielding used usually in radiology departments is being replaced by non-lead shields due to concerns over toxicity, high weight, and the impossibility of applying it in the imaging field. New studies refer to the use of nanomaterials and lightweight polymer-based composites as an alternative that can solve the problems caused by lead shields. The study aims to develop a flexible composite shield for CT scan imaging and examine its effectiveness in reducing radiation exposure. This study involved the construction of 1 mm thick composite shields used in chest CT scan imaging. The first type consisted of 10% bismuth oxide, the second type consisted of 10% tungsten, the third type consisted of 5% bismuth oxide and 5% tungsten, and 90% of the rest of the structure of all shields was silicone. This study examined the morphological test, tensile strength test, attenuation efficiency, and image quality assessment of these shields. The radiation transmission coefficient for 10% bismuth, 10% tungsten and 5% bismuth-5%tungsten shields was obtained as 0.86, 0.80, and 0.83, respectively. Also, the noise increasing percentage for mentioned shields were 6, 4, and 6%, respectively, compared to the case without a shield. The study found that the 10% tungsten-90% silicone shield is the most effective in reducing radiation exposure due to its K-edge and attenuation coefficients. According to the noise assessment, using these shields does not significantly affect the quality of images.