Background. Radiation using conventional X-ray is associated with exposure of radiosensitive organs and typically requires the use of protection. This study is aimed at evaluating the use of bismuth shielding for radiation protection in pediatric pelvic radiography. The effects of the anteroposterior and lateral bismuth shielding were verified by direct measurements at the anatomical position of the gonads. Methods. Radiation doses were measured using optically stimulated luminescence dosimeters (OSLD) and CIRS ATOM Dosimetry Verification Phantoms. Gonad radiographs were acquired using different shields of varying material (lead, bismuth) and thickness and were compared with radiographs obtained without shielding to examine the effects on image quality and optimal reduction of radiation dose. All images were evaluated separately by three pediatric orthopedic practitioners. Results. Results showed that conventional lead gonadal shielding reduces radiation doses by 67.45%, whereas dose reduction using one layer of bismuth shielding is 76.38%. The use of two layers of bismuth shielding reduces the dose by 84.01%. Using three and four layers of bismuth shielding reduces dose by 97.33% and 99.34%, respectively. Progressively lower radiation doses can be achieved by increasing the number of bismuth layers. Images obtained using both one and two layers of bismuth shielding provided adequate diagnostic information, but those obtained using three or four layers of bismuth shielding were inadequate for diagnosis. Conclusions. Bismuth shielding reduces radiation dose exposure providing appropriate protection for children undergoing pelvic radiography. The bismuth shielding material is lighter than lead, making pediatric patients more comfortable and less apt to move, thereby avoiding repeat radiography.
Background/Aim: Non-small cell lung cancer (NSCLC) is the most common type of lung cancer with poor prognosis. Lenvatinib is a multi-kinase inhibitor that has the potential to suppress tumor progression. Our previous study suggested that lenvatinib induces cytotoxicity and apoptosis in CL-1-5-F4 cells in vitro. However, whether lenvatinib suppresses NSCLC progression in vivo remains unclear. Materials and Methods: Tumor growth inhibition and normal tissue toxicity evaluation following lenvatinib treatment were performed on CL-1-5-F4-bearing mice. Results: Tumor growth calculated by caliper and living cell intensity decreased by lenvatinib treatment as analysed by bioluminescence imaging. Phosphorylation of AKT, NF-ĸB, and NF-ĸB downstream proteins involved in tumor progression were reduced by lenvatinib in the tumor tissue. No pathological changes were found in the liver, kidney, and spleen after lenvatinib treatment. Conclusion: Induction of apoptosis and suppression of AKT/NF-ĸB were associated with lenvatinib-induced inhibition of the progression of NSCLC in vivo.Current treatment of advanced non-small cell lung cancer (NSCLC) is guided by the mutation status of driver genes (1). Patients with an actionable driver gene mutation will have longer survival than those carrying no mutation when treated with receptor tyrosine kinase inhibitors (TKIs) (2). However, even with the outstanding efficacy of the third generation TKIs, progression may occur after treatment for approximately 1.5 years (3). The strategy of treatment beyond progression could be based on the identification of actionable acquired driver gene mutations in this population (4).
Industrial radiography is a common nondestructive testing (NDT) method used in various industries. An investigation was conducted for a 1999 incident in Taiwan where two workers (Operators A and B) were accidently exposed to an unshielded Ir source while conducting industrial radiography. Operators A and B experienced acute close-range radiation exposure to a source of Ir for 3 h at a strength of 2.33 × 10 Bq. The health of mammary glands, bone marrow, thyroid glands, eyes, and genital organs of these two workers after radiation exposure was examined. Subsequently, Operator A experienced severe radiation injury, including tissue necrosis and keratinization in the fingers, chromosomal abnormalities, reduced blood cell count, diffuse hyperplasia of the thyroid gland, opaque spots in the crystalline lens, and related radiation effects. The results showed that the left index finger and thumb, eyes, and gonads of Operator A were exposed to a radiation dose of about 369-1,070, 23.1-67.4, 2.4-5.3, and 4.2-11.6 Gy, respectively. Effective dose for Operator A was estimated to range from 6.9 to 18.9 Sv. The left fingers, thumb, eyes, and gonads of Operator B were exposed to a radiation dose of 184.9-646.2, 11.8-40.7, 0.49-3.33, and 0.72-7.18 Gy, respectively, and his effective dose was between 2.5 and 11.5 Sv. This accident indicated a major flaw in the control and regulation of radiation safety for conducting NDT industrial radiography in 1999; however, similar problems still exist. Modifications of the Ionizing Radiation Protection Act in Taiwan are suggested in this study to regulate the management of NDT industries, continually educate the NDT workers in radiation safety, and enact notification provisions for medical care systems toward acute radiation exposure events.
The Tc-99m methylene diphosphonate (MDP) whole body bone scan (WBBS) has been widely accepted as a method of choice for the initial diagnosis of bone and joint changes in patients with oncologic diseases. The WBBS has shown high sensitivity but relatively low specificity due to bone variation. This study aims to use the self-developing irregular flux viewer (IFV) system to predict possible bone lesions in planar WBBS. The study uses gradient vector flow (GVF) and self-organizing map (SOM) methods to analyze the blood fluid-dynamics and evaluate hot points. The evaluation includes a selection of 368 patients with bone metastasis from prostate cancer, lung cancer and breast cancer. Finally, we compare IFV values with BONENAVI version data. BONENAVI is a computer-assisted diagnosis system that analyzes bone scintigraphy automatically. The analysis shows that the IFV system achieves sensitivities of 93% for prostate cancer, 91% for breast cancer, and 83% for lung cancer, respectively. On the other hand, our proposed approach achieves a higher sensitivity than the results of BONEVAVI version 2.0.5 for prostate cancer (88%), breast cancer (86%) and lung cancer (82%), respectively. The study results demonstrate that the high sensitivity and specificity of the IFV system can provide assistance for image interpretation and generate prediction values for WBBS.
Fluoroscopy is used to track a catheter as it enters a heart or coronary arteries. However, radiation exposure, which is highly dependent on the complexity of procedures and the optimization of imaging parameters applied by clinicians, is a major concern during diagnosis. The exposure dose of a phantom protected with an optimized radiation protection device (a lead sheet directly under treatment bed) was measured using optically simulated luminescent dosimeters and compared with those in unprotected arrangement. The radiation doses of operator were significantly lower (p < 0.001) in the lens, thyroid, and gonad regions with protection (190.0 ± 39.2, 206.7 ± 43.3, and 273.3 ± 56.4 μGy, respectively) than without it (221.7 ± 11.8, 235.0 ± 49.0, and 310.0 ± 65.5 μGy). The patients without radiation protection were exposed to relatively high radiation doses in the brain, gonad, or lens regions. Thus, suitable protection against the radiation exposure should be minimized during cardiac catheterization.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.