Simultaneous microbeam IBA and beam-induced luminescence analysis of strained doped silica fibre radiation dosimeters

We demonstrate that the simultaneous combination of ion beam analysis (IBA) and ion beam induced luminescence (IL) can reveal valuable information concerning the performance of strained doped silica fibre thermoluminescence microdosimeters. The micron scale spatial resolution and low detection limits of IBA allow the lateral distribution of dopant elements to be mapped and then correlated with the distribution of prompt radioluminescence. Measurement of the decay of the IL signal with dose provide information concerning the saturation of the subsequent TL signal at high doses. MeV ion beams can deposit relatively high energy in localized, well-quantified small volumes and so this method is valuable for studying high dose effects in TL dosimeters. We describe a simple modification of the target chamber microscope which enables sensitive low background light detection in two wavelength bands and present preliminary results from three types of germanium doped silica fibre dosimeter

Investigation of silica-based TL media for diagnostic x-ray dosimetry

We focus on the development of Ge-doped silica thermoluminescent dosimeters with sensitivity superior to that of the LiF (Mg,Ti) phosphors popularly used in x-ray diagnostic imaging dosimetry, typically in the form of the product TLD-100. Of interest are Ge-doped silica telecommunication fibres (SMF) and tailor-made doped photonic crystal fibres (PCFc), the latter Ge-doped or also co-doped with boron. The PCFs are formed of capillaries that at high temperatures and under vacuum are made to collapse inwards (PCFc), the internal walls fusing and generating strain-related defects. To-date, the fabricated PCFc-Ge-B, PCFc-Ge and (SMF) have been observed to provide TL yields which weight-for-weight are some 15, 10 and 2 × that of TLD-100. In present study we test the linearity of TL yield for x-ray doses from 0.1- to 10 mGy, use being made of an x-ray tube operated at 80 kVp, a value typically selected in chest radiography. For a dose of 10 mGy, a study of energy dependence has been conducted using x-ray tube potentials of 80 kVp 100 kVp, and 120 kVp, with inherent filtration 0.9 mm Al measured at 75 kVp, and total filtration of 2.8 mm Al at 80 kVp

Evaluations of Paranasal Sinus Disease Using Multidetector Computed Tomography in Taif City, Saudi Arabia

Background: This study aimed to evaluate paranasal sinusitis disease and determine if there is a relationship between the anatomical variation of sinusitis based on the age and gender of the patient and, if so, to identify the most affected demographic group. Methods and Results: This study included 130 patients (76 men and 54 women with ages ranging from 18 years to 75 years) diagnosed with PNS disease and was conducted in the Radiology Department of King Abdelaziz Specialist Hospital and King Faisal Hospital (Taif city, Saudi Arabia) from January 1 2021 to January 31 2022. The evaluation of sinusitis was conducted using multidetector computed tomography. The clinical symptoms included 70% cases of nasal obstruction, 53% cases of headache, 28.5% cases of nasal discharge, 17.7% cases of facial pain, and 3.1% cases of general malaise. The types of sinusitis included maxillary sinusitis (88.5%), sphenoid sinusitis (28.5%), ethmoid sinusitis (43.8%), and frontal sinusitis (23.5%). The study found no significant anatomical variation of sinuses based on age and gender (P>0.05). Conclusion: An evaluation of paranasal sinusitis disease using an MDCT scan shows that there are no gender or age-related differences in the prevalence of the disease. Moreover, the study demonstrates that there is no significant anatomical variation of sinuses based on age and gender

[Corrigendum] Evaluations of Paranasal Sinus Disease Using Multidetector Computed Tomography in Taif City, Saudi Arabia

Corrigendum for 'Evaluations of Paranasal Sinus Disease Using Multidetector Computed Tomography in Taif City, Saudi Arabia' by: Alotaibi O, Osman H, Hadi Y, Alzamil Y, Alyahyawi A, Al-Enezi MS, Alafer F, Abanomy A, Khandaker MU, Almeshari M. International Journal of Biomedicine 12(4): 575-579. DOI: 10.21103/Article12(4)_OA9 Following the publication of this article, the authors have realized that errors were made with the description of the listed affiliation addresses. Therefore, the author affiliations and addresses, in this paper should have appeared as follows: Osama Alotaibi1,2, Hamid Osman3, Yasser Hadi 4, Yasser Alzamil5, Amjad Alyahyawi5,6, Mamdouh S. Al-Enezi5, Feras Alafer7, Ahmad Abanomy8, Mayeen Uddin Khandaker9,10, and Meshari Almeshari5; 1Department of Radiology, College of Applied Medical Sciences, University of Ha'il, Ha'il, Saudi Arabia 2Department of Radiology, King Abdulaziz Specialist Hospital-Taif, Taif, Saudi Arabia 3Department of Radiological Sciences, College of Applied Medical Science, Taif University, P.O. Box 2425, Taif 21944, Saudi Arabia 4Department of Medical Imaging and Intervention, King Abdullah Medical City (KAMC), Makkah, Saudi Arabia 5Department of Diagnostic Radiology, College of Applied Medical Sciences, University of Ha'il, Ha'il, Saudi Arabia. 6Centre for Nuclear and Radiation Physics, Department of Physics, University of Surrey, Guildford, Surrey GU2 7XH, UK 7Department of Radiological Sciences, College of Applied Medical Sciences, Jouf University, Sakaka, Saudi Arabia 8Department of Radiological Sciences, College of Applied Medical Sciences, King Saud University, P. O. Box 10219, Riyadh 11433, Saudi Arabia 9Centre for Applied Physics and Radiation Technologies, School of Engineering and Technology, Sunway University, Bandar Sunway, Malaysia 10Department of General Educational Development, Faculty of Science and Information Technology, Daffodil, International University, DIU Rd, Dhaka 1341, Bangladesh The authors apologize for any inconvenience caused

Silica-based Passive Dosimeters for sub-Gy Patient-focused Dose Evaluations

In use of doped silica glass TL dosimeters, previous studies by others have focused on measurement of the radiation doses delivered during radiotherapy applications, with levels of dose typically in the fractions of a Gy to some several tens of Gy level. The present work is differentiated from such efforts, the thesis evaluating the utility of several types of enhanced-sensitivity doped silica glass TL dosimeter, novel forms that have been developed for measurement of low radiation doses. The range of interest is from several μGy to several tens of mGy level (ie doses some 0.1% and less of that of the therapy doses previously investigated), the focus being on medical applications within which such exposures arise. The stochastic effects of radiation are without threshold, the probability nevertheless increasing with dose. As such, the low radiation doses that can give rise to small but extant probability of inducing cancer need to be measured, allowing for dose mitigation measures that can be evaluated. Therefore, one of the main purposes of this research is to examine the development of new dosimeters that can measure such low radiation doses, either in diagnostic uses of x-rays or in regard to scattered radiation received to the lens of the eye during stereotactic radiosurgery (SRS) applications. The diagnostic applications of choice are those which find widespread use, from single exposure dental doses, through to chest radiography and mammographic imaging. As no dosimeter exists that can come close to approximating the ideal characteristics of an omni-utility sensor, a number of glass TL dosimeter forms have been investigated, differing in dopant concentration, size and fabrication, examined for use in the different dose regimes. The characterisation of GeB-PFc, Ge-PFc, GeB-FF, Ge-doped disc, Ge-SMF and LiF (all defined in detail in the thesis) have been performed, including the study of linearity, fading, energy response, dose response, and sensitivity. The outcome is one demonstrating successful accommodation of all of the dose ranges of interest. Additional sensitivity of between 20% to 30% has been shown to be available through thin (several tens of microns) high Z coatings to flat fibres (FF), the coatings acting as photoelectron and Auger electron conversion media. Being small in size, non toxic and devoid of any electrical contact, it is the intention that these TL forms take on the important role of safe and accurate dose evaluations as an aid in dose optimization measures

Tailor-made Ge-doped silica-glass for clinical diagnostic X-ray dosimetry

In the modern clinical practice of diagnostic radiology there is a growing demand for radiation dosimetry, it also being recognized that with increasing use of X-ray examinations additional population dose will result, accompanied by an additional albeit low potential for genetic consequences. At the doses typical of diagnostic radiology there is also a low statistical risk for cancer induction; in adhering to best practice, to be also implied is a low but non-negligible potential for deterministic sensitive organ responses, including in regard to the skin and eyes. Risk reduction is important, in line with the principle of ALARP, both in regard to staff and patients alike; for the latter modern practice is usually guided by Dose Reference Levels (DRL) while for the former and members of the public, legislated controls (supported by safe working practices) pertain. As such, effective, reliable and accurate means of dosimetry are required in support of these actions. Recent studies have shown that Ge-doped-silica glass fibres offer several advantages over the well-established phosphor-based TL dosimeters (TLD), including excellent sensitivity at diagnostic doses as demonstrated herein, low fading, good reproducibility and re-usability, as well as representing a water impervious, robust dosimetric system. In addition, these silica-based fibres show good linearity over a wide dynamic range of dose and dose-rate and are directionally independent. In the present study, we investigate tailor made doped-silica glass thermoluminescence (TL) for applications in medical diagnostic imaging dosimetry. The aim is to develop a dosimeter of sensitivity greater than that of the commonly used LiF (Mg,Ti) phosphor. We examine the ability of such doped glass media to detect the typically low levels of radiation in diagnostic applications (from fractions of a mGy through to several mGy or more), including, mammography and dental radiology, use being made of x-ray tubes located at the Royal Surrey County Hospital. We further examine dose-linearity, energy response and fading

Developed a New Radiation Shielding Absorber Composed of Waste Marble, Polyester, PbCO₃, and CdO to Reduce Waste Marble Considering Environmental Safety

The usage of radiation is mandatory for modern life; in the same manner, controlling the outflow of harmful radiation is vital and could be achieved via employing a shielding material to eliminate any potential nuclear and radiation accidents and incidents. Considering this point, this study aims to manufacture composite samples based on waste marble as novel radiation shields. The physical and radiation shielding ability of the prepared shields were determined and analyzed. For this purpose, a high-purity germanium (HPGe) detector was used to detect the incoming photons emitted from three point sources (Am-241, Cs-137, and Co-60). The radiation attenuation factors for the new marble-based composites were measured for some energies, ranging from 0.06 to 1.333 MeV. We examined the effect of increasing the PbCO3 and CdO contents on the physical properties and radiation attenuation factors of the newly developed radiation shielding absorber. We found that the density of the samples increases from 1.784 to 1.796 g/cm3 when the CdO changes from 0 to 12.5 wt%. The linear attenuation coefficient (LAC) for all marble compositions has the maximum value at 0.06 MeV, while the LAC decreases with increasing energy. The highest LAC was found for Marb-3, with a composition of waste marble (50 wt%), polyester (25 wt%), PbCO3 (17.5 wt%), and CdO (7.5 wt%). We studied the impact of the addition of CdO on the expense of PbCO3 and we found that the half value layer (HVL) decreases with increasing the CdO content. Hence, when there is no space problem, the newly developed radiation shielding absorber can be used to maintain the cost effectiveness and environmentally friendliness of products

A Novel Epoxy Resin-Based Composite with Zirconium and Boron Oxides: An Investigation of Photon Attenuation

We have attempted to develop the gamma radiation shielding abilities of newly prepared epoxy composites by introducing ZrO2. The radiation shielding parameters are experimentally reported below. The experimental setup included an HPGe detector and different radioactive point sources which emitted photons with energies of 0.06, 0.662, 1.173, and 1.333 MeV. The gamma radiation shielding abilities of the epoxy composites were examined in the context of the linear attenuation coefficient (LAC), half-value layer (HVL), radiation absorption ratio, and other factors. The experimental and Phy-X results for the LAC were compared, and acceptable consistency was reported. The lowest LAC values were reported for EBZr-0 (free of ZrO2), and we found that the photon attenuation competence of the present epoxy improved as a result of increasing the ZrO2 content. We compared the LAC values for the present epoxy composites with other samples, and we found that the prepared composites with 20% to 40% ZrO2 had higher LAC values than epoxy with 30% Yahyali Stone. The HVL lengths of the epoxy composites reduced with the addition of ZrO2 for the four selected energies, which confirmed that introducing ZrO2 improves the radiation absorption abilities of epoxy composites. At 0.06 MeV, the HVL for the ZrO2-free epoxy was 2.60 cm, which fell to 0.23 cm after adding 40% ZrO2. The mean free path (MFP) for the prepared composites was less than 1 cm at 0.06 MeV (standard for EBZr-0), while it was 1.32 cm for EBZr-10. For the other energies, it was higher than 6 cm, and became higher than 10 cm at 1.333 MeV for all composites. The obtained results suggest that non-toxic, natural, and cheap epoxy composites with high ZrO2 content have the potential to improve the gamma ray shielding competence of epoxy composites for low energy radiation applications

Characterisation of an isotropic neutron source: a comparison of conventional neutron detectors and micro-silica glass bead thermoluminescent detectors

As a result of their thermoluminescent response, low cost commercial glass beads have been demonstrated to offer potential use as radiation dosimeters, providing capability in sensing different types of ionising radiation. With a linear response over a large range of dose and spatial resolution that allows measurements down to the order of 1 mm, their performance renders them of interest in situations in which sensitivity, dynamic range, and fine spatial resolution are called for. In the present work, the suitability of glass beads for characterisation of an AmericiumBeryllium (241AmBe) neutron source has been assessed. Direct comparison has been made using conventional 3He and boron tri-fluoride neutron detectors as well as Monte Carlo simulation. Good agreement is obtained between the glass beads and gas detectors in terms of general reduction of count rate with distance. Furthermore, the glass beads demonstrate exceptional spatial resolution, leading to the observation of fine detail in the plot of dose versus distance from source. Fine resolution peaks arising in the measured plots, also present in simulations, are interesting features which based on our best knowledge have previously not been reported. The features are reproduced in both experiment and simulation but we do not have a firm reason for their origin. Of greater clarity is that the glass beads have considerable potential for use in high spatial resolution neutron field characterisation, subject to the availability of a suitable automated TLD reader

Characterisation of an isotropic neutron source: a comparison of conventional neutron detectors and micro-silica glass bead thermoluminescent detectors

As a result of their thermoluminescent response, low cost commercial glass beads have been demonstrated to offer potential use as radiation dosimeters, providing capability in sensing different types of ionising radiation. With a linear response over a large range of dose and spatial resolution that allows measurements down to the order of 1 mm, their performance renders them of interest in situations in which sensitivity, dynamic range, and fine spatial resolution are called for. In the present work, the suitability of glass beads for characterisation of an AmericiumBeryllium (241AmBe) neutron source has been assessed. Direct comparison has been made using conventional 3He and boron tri-fluoride neutron detectors as well as Monte Carlo simulation. Good agreement is obtained between the glass beads and gas detectors in terms of general reduction of count rate with distance. Furthermore, the glass beads demonstrate exceptional spatial resolution, leading to the observation of fine detail in the plot of dose versus distance from source. Fine resolution peaks arising in the measured plots, also present in simulations, are interesting features which based on our best knowledge have previously not been reported. The features are reproduced in both experiment and simulation but we do not have a firm reason for their origin. Of greater clarity is that the glass beads have considerable potential for use in high spatial resolution neutron field characterisation, subject to the availability of a suitable automated TLD reader