SpaceOAR, a Food and Drug Administration–approved hydrogel intended to create a rectal–prostate space, was evaluated in a single-blind phase III trial of image guided intensity modulated radiation ...therapy. A total of 222 men were randomized 2:1 to the spacer or control group and received 79.2 Gy in 1.8-Gy fractions to the prostate with or without the seminal vesicles. The present study reports the final results with a median follow-up period of 3 years.
Cumulative (Common Terminology Criteria for Adverse Events, version 4.0) toxicity was evaluated using the log-rank test. Quality of life (QOL) was examined using the Expanded Prostate Cancer Index Composite (EPIC), and the mean changes from baseline in the EPIC domains were tested using repeated measures models. The proportions of men with minimally important differences (MIDs) in each domain were tested using repeated measures logistic models with prespecified thresholds.
The 3-year incidence of grade ≥1 (9.2% vs 2.0%; P=.028) and grade ≥2 (5.7% vs 0%; P=.012) rectal toxicity favored the spacer arm. Grade ≥1 urinary incontinence was also lower in the spacer arm (15% vs 4%; P=.046), with no difference in grade ≥2 urinary toxicity (7% vs 7%; P=0.7). From 6 months onward, bowel QOL consistently favored the spacer group (P=.002), with the difference at 3 years (5.8 points; P<.05) meeting the threshold for a MID. The control group had a 3.9-point greater decline in urinary QOL compared with the spacer group at 3 years (P<.05), but the difference did not meet the MID threshold. At 3 years, more men in the control group than in the spacer group had experienced a MID decline in bowel QOL (41% vs 14%; P=.002) and urinary QOL (30% vs 17%; P=.04). Furthermore, the control group were also more likely to have experienced large declines (twice the MID) in bowel QOL (21% vs 5%; P=.02) and urinary QOL (23% vs 8%; P=.02).
The benefit of a hydrogel spacer in reducing the rectal dose, toxicity, and QOL declines after image guided intensity modulated radiation therapy for prostate cancer was maintained or increased with a longer follow-up period, providing stronger evidence for the benefit of hydrogel spacer use in prostate radiation therapy.
A rapid method for the determination of polonium-210 in air filters has been created for use following a radiological event and for routine environmental monitoring. Air filter samples, including ...cellulose and glass fiber, are fused with a sodium or potassium nitrate/sodium hydroxide flux material. The alkaline matrix minimizes polonium volatility during sample digestion steps, while efficiently dissolving the air filter and inorganic matter implanted on the filter. The addition of nitrate to the flux destroys organic material which can decrease Polonium recovery during precipitation, extraction and source preparation steps. Polonium is concentrated and separated from the sample matrix using an iron hydroxide precipitation and extraction chromatography with DGA Resin. Polonium-210 is subsequently measured by alpha spectrometry following rapid microprecipitation with bismuth phosphate. The new method employs extraction chromatographic purification to remove alpha emitting interferences and sample matrix constituents which can interfere with 210Po measurements using alpha spectrometry. The novel blend of sodium hydroxide and alkali metal nitrate digests the air filters quickly and effectively.
•Improvement of CT scanner hardware made a substantial contribution to the radiation dose reduction of computed tomography.•Current reduction, potential modification, and refinement of image ...production algorithms are the key dose reduction methods.•Automatic exposure control and iterative reconstruction methods play a significant role in the CT radiation dose reduction.•The validity of dose reduction can be evaluated with objective and subjective image quality, and diagnostic accuracy.•Realizing the reference dose level for common CT imaging protocols is necessary to avoid overdose in the CT examinations.
Although radiation dose in computed tomography (CT) decreased and CT became safer examinations than before, CT is the most significant source of the medical radiation exposure. Knowledge about available radiation dose reduction methods in CT is essential.
Substantial improvement occurred regarding tube current selection (automatic exposure control) and image production method (iterative reconstruction). Optimizing the tube potential selection is expected to contribute to further CT radiation dose reduction.
This review article summarizes the principles of radiation dose reduction in CT, principal methods of radiation dose reduction, auxiliary measures of radiation dose saving and recent issues of low dose CT.
In the present work, we fabricated a series of six glasses to be utilized in the field of radiation shielding application. Glasses have been synthesized using a melt-quenching ordinary technique. In ...this work, we investigated the structural properties of these glasses using Raman spectroscopy. Moreover, optical properties have been studied in the present work. The radiation attenuation ability for the present samples was also investigated and measured using transmission geometry between 81 and 964.1 keV. The mass attenuation coefficient was measured and the results were validated by the WinXcom program. Also, radiation protection efficiency (RPE) was evaluated and discussed in terms of photon energy and Bi2O3 concentration. From RPE curve, we found that the fabricated glasses can be used as effective shielding materials especially for the low energies (81–383 keV). The half value layer also was calculated and the results of this parameter showed that S6 (contains 60 mol% of Bi2O3) has the higher probability of the interaction with gamma photons, leading to less number of photons transmitted this sample and thus better photon attenuator.
•B2O3–10ZnO–10MgO-xBi2O3 glasses.•Theoretical and experimental validation Radiation shielding characteristics of synthesized glasses have been investigated.•Raman spectroscopy of glasses.•Optical band gap of fabricated glasses.
In recent years, the intersection of the academic and medical domains has increasingly spotlighted the utilization of biomaterials in radioactive disease treatment and radiation protection. ...Biomaterials, distinguished from conventional molecular pharmaceuticals, offer a suite of advantages in addressing radiological conditions. These include their superior biological activity, chemical stability, exceptional histocompatibility, and targeted delivery capabilities. This review comprehensively delineates the therapeutic mechanisms employed by various biomaterials in treating radiological afflictions impacting the skin, lungs, gastrointestinal tract, and hematopoietic systems. Significantly, these nanomaterials function not only as efficient drug delivery vehicles but also as protective agents against radiation, mitigating its detrimental effects on the human body. Notably, the strategic amalgamation of specific biomaterials with particular pharmacological agents can lead to a synergistic therapeutic outcome, opening new avenues in the treatment of radiation- induced diseases. However, despite their broad potential applications, the biosafety and clinical efficacy of these biomaterials still require in-depth research and investigation. Ultimately, this review aims to not only bridge the current knowledge gaps in the application of biomaterials for radiation-induced diseases but also to inspire future innovations and research directions in this rapidly evolving field.
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The harm that society expects from ionizing radiation does not match experience. Evidently there is some basic error in this assumption. A reconsideration based on scientific principles shows how ...simple misunderstandings have exaggerated dangers. The consequences for society are far-reaching. The immediate impact of ionizing radiation on living tissue is destructive. However, this oxidative damage is similar to that produced during normal metabolic activity where the subsequent biological reaction is not only protective but also stimulates enhanced protection. This adaptation means that the response to oxidative damage depends on past experience. Similarly, social reaction to a radiological accident depends on the regulations and attitudes generated by the perception of previous instances. These shape whether nuclear technology and ionizing radiation are viewed as beneficial or as matters to avoid. Evidence of the spurious damage to society caused by such persistent fear in the second half of the 20 th century suggests that these laws and attitudes should be rebased on evidence. The three stages of radiological impact-the initial physical damage, the subsequent biological response, and the personal and social reaction-call on quite different logic and understanding. When these are confused, they lead to regulations and public policy decisions that are often inept, dangerous, and expensive. One example is when the mathematical rigor of physics, appropriate to the immediate impact, is misapplied to the adaptive behavior of biology. Another, the tortured historical reputation of nuclear technology, is misinterpreted as justifying a radiological protection policy of extreme caution.Specialized education and closed groups of experts tend to lock in interdisciplinary misperceptions. In the case of nuclear technology, the resulting lack of independent political confidence endangers the adoption of nuclear power as the replacement for fossil fuels. In the long term, nuclear energy is the only viable source of large-scale primary energy, but this requires a re-working of public understanding.
An alternative approach that is particularly suitable for the radiation health risk assessment (HRA) of astronauts is presented. The quantity, Radiation Attributed Decrease of Survival (RADS), ...representing the cumulative decrease in the unknown survival curve at a certain attained age, due to the radiation exposure at an earlier age, forms the basis for this alternative approach. Results are provided for all solid cancer plus leukemia incidence RADS from estimated doses from theoretical radiation exposures accumulated during long-term missions to the Moon or Mars. For example, it is shown that a 1000-day Mars exploration mission with a hypothetical mission effective dose of 1.07 Sv at typical astronaut ages around 40 years old, will result in the probability of surviving free of all types of solid cancer and leukemia until retirement age (65 years) being reduced by 4.2% (95% CI 3.2; 5.3) for males and 5.8% (95% CI 4.8; 7.0) for females. RADS dose–responses are given, for the outcomes for incidence of all solid cancer, leukemia, lung and female breast cancer. Results showing how RADS varies with age at exposure, attained age and other factors are also presented. The advantages of this alternative approach, over currently applied methodologies for the long-term radiation protection of astronauts after mission exposures, are presented with example calculations applicable to European astronaut occupational HRA. Some tentative suggestions for new types of occupational risk limits for space missions are given while acknowledging that the setting of astronaut radiation-related risk limits will ultimately be decided by the Space Agencies. Suggestions are provided for further work which builds on and extends this new HRA approach, e.g., by eventually including non-cancer effects and detailed space dosimetry.
With great interest we have read the paper “Pregnancy Screening before Diagnostic Radiography in Emergency Department; an Educational Review†by A.I. Abushouk et al. (1). We agree with the authors ...that unnecessary fetal radiation exposure should be avoided and that pregnancy screening can be a means to accomplish this. However, in their paper the authors suggest in several instances that radiological imaging during pregnancy can lead to teratogenic effects. In the Abstract it is stated: “Radiation exposure during pregnancy may have serious teratogenic effects to the fetus. Therefore, checking the pregnancy status before imaging women of child bearing age can protect against these effects.â€, and in the Introduction: “Therefore, checking the pregnancy status before imaging women of child bearing age can protect against radiation teratogenic effects.â€
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