The effectiveness of bismuth breast shielding with protocol optimization in CT scans of the thorax

Background: Numerous techniques had been proposed to reduce radiation exposure in computed tomography (CT) including the use of radiation shielding. Objective: This study aims to evaluate efficacy of using a bismuth breast shield and optimized scanning parameter to reduce breast absorbed doses from CT thorax examination. Methods: Five protocols comprising the standard CT thorax clinical protocol (CP1) and four modified protocols (CP2 to CP5) were applied in anthropomorphic phantom scans. The phantom was configured as a female by placing a breast component on the chest. The breast component was divided into four quadrants, where 2 thermoluminescence dosimeters (TLD-100) were inserted into each quadrant to measure the absorbed dose. The bismuth shield was placed over the breast component during CP4 and CP5 scans. Results: The pattern of absorbed doses in each breast and quadrant were approximately the same for all protocols, where the 4th quadrant > 3rd quadrant > 2nd quadrant > 1st quadrant. The mean absorbed dose value in CP3 was reduced to almost 34% of CP1's mean absorbed dose. It was reduced even lower to 15% of CP1's mean absorbed dose when the breast shield was used in CP5. Conclusion: This study showed that CT radiation exposure on the breast could be reduced by using a bismuth shield and low tube potential protocol without compromising the image quality

Impact of Al2O3 and Dy2O3 substitution on the physical, structural and radiation shielding properties of Li2O-B2O3 glass system

A new series of lithium-borate glass systems (23Li2O-72B2O3 in mol%) were synthesized with the substitution of Al2O3 (5 mol.%) as a modifier and doped with 0.3 and 0.5 mol% of Dy2O3. Four series of glasses (S1, S2, S3 and S4) were synthesized via the conventional melt-quenching technique and characterized by using UV-Visible-NIR absorption spectrometer and Fourier transform infrared (FTIR) spectroscopy. The current investigation gives further insight on the structural and optical properties of the samples. The diffraction spectrum obtained from the X-ray Diffraction (XRD) analysis shows no typical peaks in the glass system, which indicates its amorphous phase. The optical properties of Al3+ and Dy3+ ions were evaluated and found that there is a pivot effect for the addition of Al2O3 and Dy2O3 for the glass system. Notably, the sample S2 shows different behaviours for physical, structural, and optical properties compared with other prepared glass samples that can be attributed to the increment of Al2O3. Besides, the physical and ionizing shielding features were investigated for current glass samples. The radiation shielding properties were examined within the energy range of 0.015 until 15 MeV. The sample S4 has the optimum radiation shielding features as a result of the addition of Dy2O3. Hence, the composition attributes a new glass system that can be used in various applications such as radiation dosimeter and photon shielding materials

Optical and structural properties of lithium sodium borate glasses doped Dy3+ ions

Absorption and emission spectra of lithium sodium borate glass doped with different concentrations of Dy3+ have been reported. The concentration of Dy3+ was varied from 0.3 to 1.3 mol%. The amorphous nature of the prepared samples was confirmed by the X-ray Diffraction (XRD). Fourier transforms infrared (FTIR) spectra, and other significant physical properties (energy band gap, density, ion concentration, molar volume, Polaron radius and inter-nuclear distance) have been analyzed in the light of the different oxidation states of the co-dopant ions. The absorption spectrum showed nine peaks with hypersensitive transition corresponding to 6F11/2 + 6H9/2 at 1256 nm. As a result of 380 nm excitation wavelength, the luminescence spectra showed two characteristic bands at 479 nm and 587 nm. These absorption bands were attributed to 6P15/2 → 6H15/2 and 6P15/2 → 6H13/2 transitions of trivalent Dy3+ ions. The current study indicates that Dy doped lithium sodium borate glasses are attractive for solid-state laser applications

Estimation of radiation cancer risk in CT-KUB

The increased demand for computed tomography (CT) in radiological scanning examinations raises the question of a potential health impact from the associated radiation exposures. Focusing on CT kidney-ureter-bladder (CT-KUB) procedures, this work was aimed at determining organ equivalent dose using a commercial CT dose calculator and providing an estimate of cancer risks. The study, which included 64 patients (32 males and 32 females, mean age 55.5 years and age range 30–80 years), involved use of a calibrated CT scanner (Siemens-Somatom Emotion 16-slice). The CT exposures parameter including tube potential, pitch factor, tube current, volume CT dose index (CTDIvol) and dose-length product (DLP) were recorded and analyzed using CT-EXPO (Version 2.3.1, Germany). Patient organ doses, including for stomach, liver, colon, bladder, red bone marrow, prostate and ovaries were calculated and converted into cancer risks using age- and sex-specific data published in the Biological Effects of Ionizing Radiation (BEIR) VII report. With a median value scan range of 36.1 cm, the CTDIvol, DLP, and effective dose were found to be 10.7 mGy, 390.3 mGy cm and 6.2 mSv, respectively. The mean cancer risks for males and females were estimated to be respectively 25 and 46 out of 100,000 procedures with effective doses between 4.2 mSv and 10.1 mSv. Given the increased cancer risks from current CT-KUB procedures compared to conventional examinations, we propose that the low dose protocols for unenhanced CT procedures be taken into consideration before establishing imaging protocols for CT-KUB

Novel Tellurite Glass (60-x)TeO2–10GeO2 -20ZnO–10BaO - xBi2O3 for Radiation Shielding

In this article, high dense glasses based heavy metal former and modifier have been synthesized. The glass system with composition formula of (60-x)TeO2–10GeO2 -20ZnO–10BaO - xBi2O3 (where x = 2.5, 5, 7.5, and 10 mol. %). The glasses have been produced using the usual melt, quenching, and annealing process. Many physical features were investigated. To confirm the amorphous nature of theses glasses, we examined the samples with X-ray diffraction in the range of between 10° and 80°. Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) transmission spectrum for the current glass samples within the range of 400–1500 cm−1 has been recorded to study the behavior of the obtained glasses that is mixed between tellurium and germanium glass phase. To study the transparency and cut-off wavelength and other optical properties, Ultraviolet–Visible spectrometer (UV–Vis) was utilized between 200 and 800 nm. Radiation shielding ability of the (60-x) TeO2–10GeO2-20ZnO–10BaO-xBi2O3 glasses was examined. Monte Carlo simulation method was applied to estimate the shielding parameters for gamma photons with various energies varied in rang from 0.015 to 15 MeV. © 2020 Elsevier B.V.All Authors present their grateful acknowledge to the Universiti Putra Malaysia (UPM), for supporting this work by chemicals and services, which granted by UPM under IPB-9554200

Germanate Oxide Impacts on the Optical and Gamma Radiation Shielding Properties of TeO2-ZnO-Li2O Glass System

In this work, a series of tellurite glass combined with various concentrations of germanium oxide was fabricated according to the formula of (70-x)TeO2-xGeO2–20ZnO-10Li2O where x = 5, 10, 15 and 20 mol% via utilizing the melt-quench method for possible use in a radiation shielding applications. X-ray diffraction and Attenuated Total Reflectance Fourier Transform Infrared was employed to investigate the structure of the synthesized glasses. The density and Poisson's ratio for current samples reduced gradually from 5.221–5.008 g.cm−3 and 0.134–0.131, respectively, while the enhancement in bandgap values from 3.700–3.872 eV with addition of GeO2 is observed. The linear attenuation coefficient values at 0.015 MeV are 230.123 and 236.832 cm−1 for samples TG1 and TG4, respectively. Moreover, the lowest half-value layer attained via TG1 and raises from 0.0030 to 3.6684 cm while the highest HVL attained by TG4 and raises from 0.0029 to 3.9696 cm. © 2020 Elsevier B.V.All Authors present their grateful acknowledge to the Universiti Putra Malaysia (UPM), for supporting this work by chemicals and services, which granted by UPM under IPB-9554200. Also, the authors present their grateful acknowledge to the university of Tabuk, Tabuk, Saudi Arabia for supporting this work by some chemicals

Glow curve analysis of glassy system dosimeter subjected to photon and electron irradiations

The current paper illustrates glow curve analysis of newly developed Borate glass dosimeters. A series of dosimetric properties including dose response for photons and electrons, energy response, optical fading, and precision were determined. Glow curve deconvolution based on the general order kinetics equation was applied to extract the trapping parameters. Excellent fitting was obtained with the superposition of three-second order glow peaks. The quality of fitting was monitored through the r2 value which is always in excess of 0.9998. Thermoluminescence (TL) measurements showed that the material exhibits good linear dose–response over the delivered range of absorbed dose from 0.5 to 4 Gy for photons and electrons irradiation with low energy dependence. The material exhibits large signal loss when exposed to direct sunlight and moderate signal loss when exposed to fluorescent light. Therefore, it is recommended to use the current dosimeters indoor and to avoid prolonged direct exposure to fluorescent light. This combination of properties makes the material suitable for radiation dosimetry

Germanate oxide impacts on the optical and gamma radiation shielding properties of TeO2-ZnO-Li2O glass system

In this work, a series of tellurite glass combined with various concentrations of germanium oxide was fabricated according to the formula of (70-x)TeO2-xGeO2–20ZnO-10Li2O where x = 5, 10, 15 and 20 mol% via utilizing the melt-quench method for possible use in a radiation shielding applications. X-ray diffraction and Attenuated Total Reflectance Fourier Transform Infrared was employed to investigate the structure of the synthesized glasses. The density and Poisson's ratio for current samples reduced gradually from 5.221–5.008 g.cm−3 and 0.134–0.131, respectively, while the enhancement in bandgap values from 3.700–3.872 eV with addition of GeO2 is observed. The linear attenuation coefficient values at 0.015 MeV are 230.123 and 236.832 cm−1 for samples TG1 and TG4, respectively. Moreover, the lowest half-value layer attained via TG1 and raises from 0.0030 to 3.6684 cm while the highest HVL attained by TG4 and raises from 0.0029 to 3.9696 cm

Impact of Modifier Oxides on Mechanical and Radiation Shielding Properties of B2O3-SrO-TeO2-RO Glasses (Where RO = TiO2, ZnO, BaO, and PbO)

The influence of modifier oxides (TiO2, ZnO, BaO, and PbO) on the mechanical and radiation shielding properties of boro-tellurate glasses is investigated. Samples with a composition of B2O3-SrO-TeO2-RO (RO represents the modifier oxides) were fabricated using the melt quench method, and their physical, mechanical, and radiation attenuation parameters were reported. For this aim, Monte Carlo simulation was employed to predict the radiation attenuation parameters, while the Makishima-Mackenzie model was adopted to determine the mechanical properties. The tightly packed structure with better cross-linkage density is possessed by the Ti-containing glass (SBT-Ti) system among the titled glass batch. The higher Poisson and micro-hardness values of the SBT-Ti glass indicate its structure’s reduced free volume and better compactness. For the glass with PbO, the linear and mass attenuation coefficients are highly increased compared to those glasses doped with TiO2, ZnO, and BaO. The thinner half-value layer was reported at 0.015 MeV, taking values 0.006, 0.005, 0.004, and 0.002 for samples with TiO2, ZnO, BaO, and PbO, respectively. SBT-Pb sample (with PbO) has a thinner HVL compared to other fabricated glass samples. The fabricated glasses’ thickness (Deq) equivalent to 1 cm of lead (Pb) was reported. The results demonstrated that Deq is high at low energy and equals 11.62, 8.81, 7.61, 4.56 cm for SBT-Ti, SBT-Zn, SBT-Ba, and SBT-Pb glass samples, respectively. According to the Deq results, the fabricated glasses have a shielding capacity between 30 and 43% compared to the pure Pb at gamma-ray energy of 1.5 MeV. At high energy (8 MeV), the transmission factor values for a thickness of 1 cm of the fabricated samples reach 88.68, 87.83, 85.95, and 83.11% for glasses SBT-Ti, SBT-Zn, SBT-Ba, and SBT-Pb, respectively. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.The authors acknowledge the support of Taif University Researchers Supporting Project number (TURSP-2020/127), Taif University, Taif, Saudi Arabia