The aim of this work was to develop a novel artifact-free eye shield and evaluate its effect on the dose received by the eye lens and the resulting image quality in the CT examination of the head. A new material for an eye shield was synthesised from silicon rubber (SR) and lead (Pb) using a simple method. The percentage of Pb was varied from 0 to 5% wt. An anthropomorphic head phantom was scanned with and without the SR-Pb eye shield, and compared with a tungsten paper (WP) eye shield. The distance from the eye shield and head was varied from 0 to 5 cm. The dose to the eye lens was measured using photo-luminescence detectors (PLDs). The presence of artifacts was determined by measuring CT numbers at different eye lens locations and by subtracting images with and without the eye shield. The dose reduction increases with increasing Pb content in the SR-Pb eye shield. A 5% wt SR-Pb eye shield reduced the eye lens dose by up to 50%, whereas the WP eye shield reduced the dose by up to 86%. The CT numbers in images with the SR-Pb eye shield in the regions of both eyes and the center of the head phantom is similar to those without the eye shield, indicating that there is no artifact in the resulting image. Using the WP eye shield, there is considerable artifact with the CT number increasing by up to 700% in the regions of both eyes and the center of the head. It is found that the distance between the SR-Pb eye shield and the head does not affect either the dose or the resulting images. A SR-Pb-based eye shield can be applied in clinical environments and should be placed directly above the eye surface for dose optimisation.

This study was to evaluate dose reduction and resulting image quality of a new synthetic thyroid shield based on silicon rubber (SR)-lead (Pb) composites and compare to tungsten paper (WP) and a Radibabarrier thyroid shields in CT examination of the neck. The synthetic SR-Pb thyroid shield had a Pb percentage from 0 to 5 wt% and a thickness of 0.6 cm. Scanning on the neck of an anthropomorphic phantom was performed with and without the SR-Pb, WP, and Radibarrier thyroid shields. The thyroid shields were placed directly on the neck surface. The thyroid dose was measured using radiophoto-luminescence (RPL) detectors. Image quality was characterized by consistency of the Hounsfield unit (HU) on the areas of anterior, posterior and lateral of the neck phantom. Detailed evaluation of the image quality was employed by image subtraction. It was found that the thyroid dose at the surface decreased with an increase of Pb percentage in the SR-Pb shield. The thyroid dose reduction was 34% for a Pb percentage of 5 wt%. The reduction of the dose using WP and Radibarrier were 36% and 67%, respectively. The dose reduction when using the WP and Radibarrier was higher than when using the SR-Pb 5 wt% thyroid shield. However the existence of artifact in the WP and the Radibarrier reduced the image quality, indicated by a significant change of HU, i.e. the increases of HU in the posterior area were 77% for the WP and 553% for the Radibarrier. The SR-Pb shield produced only a very small artifact, resulting in an increase of HU in the posterior area of only 9%. The SR-Pb shield is suitable in the daily clinical setting for thyroid dose reduction in CT examinations while maintaining image quality.

Digital Radiography (DR) uses poly-energy x-rays beams, where low-energy x-rays are easily absorbed by the tissues and do not contribute to the image, therefore the low energy x-rays should be removed from the beam. The use of the radiation filter is an effective method for minimizing low-energy. The purpose of the research was to produce an alternative radiation filter for protecting organs and minimizing the dose received by patients while maintaining the quality of the image in DR examination. In this study, the radiation filters were made from Silicone Rubber–Lead Acid (SR-Pb), with the dimension of 17 x 17 x 0.6 cm3. The Pb percentage in the SR-Pb was varied from 0 to 5 wt%. To find out the feasibility of SR-Pb as a radiation filter, the dose reduction was measured using a solid-state detector (the Piranha detector, RTI Electronics, Sweden). For image quality assessment, images of the foot phantom were visually analyzed. The contrast-to-noise ratio (CNR) and signal-to-noise-ratio (SNR) values of the CDR TOR phantom with and without an SR-Pb radiation filter were measured. By the addition of Pb wt%, the foot image is still in the readable range. Analysis from the TOR CDR phantom, provided that there is no significant different between CNR and SNR value with and without SR-Pb radiation filter. The addition of Pb wt% slightly reduced the CNR and increased the SNR. SR-Pb 5 wt% decreased dose down to about 50%. This study has successfully developed the SR-Pb as an alternative radiation filter for the protection in DR examination, especially for indications that do not require an excellent low-contrast image, for example in the bone examination.

Background: Some organs in the body are sensitive to radiation such as eyes, breast, and gonads. Protection of sensitive organs against radiation is necessary. Recently, many sensitive organ shields have been developed from different materials. Objective: The aim of this study is to evaluate the dose reduction and image quality from implementation of Silicone Rubber-Lead (SR-Pb) as an alternative gonad shield in digital radiography (DR). Material and Methods: In this experimental study, the SR-Pb gonad shields with various thicknesses of 2, 4, 6, 8, and 10 mm were synthesized. This study used the Pb percentage of 5 wt%. An anthropomorphic phantom was used in abdomen plain examinations. The results obtained from the use of the SR-Pb was compared with standard gonad shield, i.e. lead apron. To measure the dose reduction, the Piranha detector was used. The image quality assessment was evaluated with the signal-to-noise ratio (SNR) and the contrast-to-noise ratio (CNR). Results: This study showed the dose reduction was significant for all SR-Pb thicknesses, and incrementally increased with the increase of the SR-Pb thickness. The minimum and maximum of dose reduction were 22.8% for 2 mm and 66.9% for 10 mm SR-Pb, respectively. Conclusion: Compared to the reference image without gonad shield, the SNR and CNR do not significantly change. Hence, the SR-Pb is probably to be used as an alternative gonad shield.

Solid polymer electrolytes (SPEs) are vital components of fast appearing technology for energy storage-conversion devices. Here, SPEs based on silver (Ag) and zinc oxide (ZnO) nanoparticles are prepared by laser ablation in polylactic acid (PLA) at room temperature. The comparison study of PLA, PLA-ZnO, PLA-ZnO/Ag, and PLA-Ag -based SPEs is conducted in pursuance of the electrical conductivity obtained from electrochemical impedance spectroscopy (EIS) characterization. EIS provides comprehensive analyses, including DC and AC conductivities, dielectric constant, and electrical modulus of the samples. Our results show that PLA-ZnO exhibits an appreciable value of DC conductivity, which insignificantly decreases by Ag addition into PLA-ZnO/Ag. This study suggests that PLA-ZnO remains stable by Ag incorporation; hence, PLA-ZnO/Ag has a great potential as SPEs.