scholarly journals Effect of Backscattered Radiation on X-Ray Image Contrast

2017 ◽  
Vol 9 (1) ◽  
pp. 105
Author(s):  
A. T. Naji ◽  
M. S. Jaafar ◽  
E. A. Ali ◽  
S. K. J. Al-Ani
Keyword(s):  
Radiation Exposure ◽  
Image Contrast ◽  
X Rays ◽  
Peak Voltage ◽  
X Ray ◽  
Geometrical Design ◽  
Remarkable Effect ◽  
Test Tool ◽  
Different Types

This paper assesses the effect of backscattered radiation on X-ray image contrast by evaluating the effect of backscatter reduction on X-ray image contrast. Contrast test tool RMI Densitometer, and different types of fabricated anti backscattered grids have been utilized in this study. The measurements are recorded at different exposure parameters such as X-ray tube peak voltage (kVp), and X-rays intensities (mAs). For each exposure, the contrast of the image is evaluated by measuring the variation in optical densities for aluminium steps wedge. The results showed that the x-ray image contrast can be enhanced by decreasing the amount of backscattered radiation, also the fabricated anti backscattered grids have a remarkable effect in the improvement of X-ray image contrast according to grid’s capability in reducing backscattered radiation. In addition, the effectiveness of fabricated grids in improving image contrast depends on the grid’s material and the geometrical design, as well as the radiation exposure parameters. The image contrast enhancements increased up to 36% with the use of crossed iron steel grid which placed under the film screen combination during exposure.

scholarly journals Truncated Inception Net: COVID-19 Outbreak Screening using Chest X-rays

2020 ◽  
Author(s):  
Dipayan Das ◽  
KC Santosh ◽  
Umapada Pal
Keyword(s):  
Neural Network ◽  
World Wide ◽  
Imaging Techniques ◽  
Imaging Systems ◽  
Ct Scans ◽  
X Rays ◽  
X Ray ◽  
X Ray Imaging ◽  
Proposed Model ◽  
Different Types

Abstract Since December 2019, the Coronavirus Disease (COVID-19) pandemic has caused world-wide turmoil in less than a couple of months, and the infection, caused by SARS-CoV-2, is spreading at an unprecedented rate. AI-driven tools are used to identify Coronavirus outbreaks as well as forecast their nature of spread, where imaging techniques are widely used, such as CT scans and chest X-rays (CXRs). In this paper, motivated by the fact that X-ray imaging systems are more prevalent and cheaper than CT scan systems, a deep learning-based Convolutional Neural Network (CNN) model, which we call Truncated Inception Net, is proposed to screen COVID-19 positive CXRs from other non-COVID and/or healthy cases. To validate our proposal, six different types of datasets were employed by taking the following CXRs: COVID-19 positive, Pneumonia positive, Tuberculosis positive, and healthy cases into account. The proposed model achieved an accuracy of 99.96% (AUC of 1.0) in classifying COVID- 19 positive cases from combined Pneumonia and healthy cases. Similarly, it achieved an accuracy of 99.92% (AUC of 0.99) in classifying COVID-19 positive cases from combined Pneumonia, Tuberculosis and healthy CXRs. To the best of our knowledge, as of now, the achieved results outperform the existing AI-driven tools for screening COVID-19 using CXRs.

scholarly journals Patient Knowledge Regarding Radiation Exposure from Orthopaedic Foot and Ankle Imaging

2018 ◽  
Vol 3 (3) ◽  
pp. 2473011418S0015
Author(s):  
Daniel Bohl ◽  
Blaine Manning ◽  
George Holmes ◽  
Simon Lee ◽  
Johnny Lin ◽  
...  
Keyword(s):  
Ionizing Radiation ◽  
Ct Scan ◽  
Radiation Exposure ◽  
Cone Beam Ct ◽  
Plain Film ◽  
Ct Scans ◽  
Cone Beam ◽  
X Rays ◽  
Foot And Ankle ◽  
X Ray

Category: Other Introduction/Purpose: Foot and ankle surgeons routinely prescribe diagnostic imaging that exposes patients to potentially harmful ionizing radiation. The purpose of this study is to characterize patients’ knowledge regarding radiation exposure associated with common forms of foot and ankle imaging. Methods: A survey was administered to all new patients prior to their first foot and ankle clinic appointments. Patients were asked to compare the amount of harmful radiation associated with chest x-rays to that associated with various types of foot and ankle imaging. Results were tabulated and compared to actual values of radiation exposure from the published literature. Results: A total of 890 patients were invited to participate, of whom 791 (88.9%) completed the survey. The majority of patients believed that a foot x-ray, an ankle x-ray, a “low dose” CT scan of the foot and ankle (alluding to cone-beam CT), and a traditional CT scan of the foot and ankle all contain similar amounts of harmful ionizing radiation to a chest x-ray (Table 1). This is in contrast to the published literature, which suggests that foot x-rays, ankle x-rays, cone beam CT scans of the foot and ankle, and traditional CT scans of the foot and ankle expose patients to 0.006, 0.006, 0.127, and 0.833 chest x-rays worth of radiation. Conclusion: The results of the present study suggest that patients greatly over-estimate the amount of harmful ionizing radiation associated with plain film and cone-beam CT scans of the foot and ankle. Interestingly, their estimates of radiation associated with traditional CT scans of the foot and ankle were relatively accurate. Results suggest that patients may benefit from increased counseling by surgeons regarding the relatively low risk of radiation exposure associated with plain film and cone-beam CT imaging of the foot and ankle.

Using a Polycapillary Optic as a Spatial Filter to Improve Micro Xray Analysis in Low-Vacuum and Environmental SEM Systems

2001 ◽  
Vol 7 (S2) ◽  
pp. 700-701
Author(s):  
Ning Gao ◽  
David Rohdeb
Keyword(s):  
Energy Dispersive Spectrometer ◽  
Spatial Filter ◽  
Image Contrast ◽  
Detection Sensitivity ◽  
X Rays ◽  
High Background ◽  
X Ray ◽  
Curved Channels ◽  
Probe Form ◽  
Environmental Sem

An inevitable consequence of the presence of the gas in the sample chamber of a low-vacuum scanning electron microscope (LV-SEM) and environmental SEM (ESEM) is the electron beam broadening due to the scattering in the gas. The electron broadening has a large impact on x-ray analysis because the fluorescent characteristic x rays generated far from the center of the electron probe form a high background, which reduces the detection sensitivity of x-ray analysis and degrades the x-ray image contrast. We report in this paper of using a polycapillary focusing x-ray optic between the sample and the energy-dispersive spectrometer as a spatial filter to filter out unwanted x-rays generated far from the specimen. As a result, the x-ray image contrast and the detection sensitivity of the system were notably improved.A polycapillary focusing optic collects a large solid angle of x rays from an x-ray source of small area at its input focus, guide them through the curved channels by multiple external total reflections, and focus them to the output focus.

Etiology analysis and x-ray diagnostics of feline odontoclastic resorbtive lesion

2020 ◽  
Vol 1 ◽  
pp. 157-162
Author(s):  
Yu. V. Mukiy ◽  
◽  
V. A. Nikolaeva ◽  
Keyword(s):  
Veterinary Medicine ◽  
Statistical Analysis ◽  
Reliable Data ◽  
Statistical Information ◽  
X Rays ◽  
X Ray ◽  
Different Types

In veterinary medicine, one of the most relevant area is dentistry of small pets. Of all dentistry diseases - 80% of cases are due to Feline odontoclastic resorptive lesion (FORL), which is more often diagnosed in cats. 35 cats have been diagnosed with den-tal disorders in vet-clinic "Altervet" for the period from November 2018 to April 2019. The analysis of the statistical information was carried out: 86 % of cats, that is 30 heads, were diagnosed FORL. The assess-ment was carried out according to the degree of tooth damage from x-rays images, and there are 2 types of resorption today: type 1 and type 2. Moreover, one of the examined cats simultaneously detected both types of FORL. Various degrees of tooth damage have been studied. Lesions of various parts of the tooth (crowns, necks, aboral and ros-tral roots of the teeth) were found, which were marked on radiographs. A statistical analysis of the incidence by breed, age, sex of animals and types of feed was conducted. The middle animal age of the disease inci-dence is 10 years. It was found that animals with pathology were nourished different types of food: mixed, dry, wet and natural. However, a greater number of cats with FORL were fed mixed (14 heads) and dry (8 heads) feed, 47 and 27%, respectively. It was found that in male this pathology is di-agnosed more often, in our case it is 73%, than in female- 27%.The disease was more common in mongrel cats – 18 heads, than in thoroughbred animals -12 heads, it turned out 60 and 40% of the number of affected animals. Reliable data on the influence of sex and breed on the occurrence of FORL has not been established.

scholarly journals Chest Exposure to X-Rays of Female Interventional Electrophysiologist

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Giaccardi M ◽  
◽  
Turreni F ◽  
Rossi F ◽  
Chechi T ◽  
...  
Keyword(s):  
Radiation Exposure ◽  
Personal Protective Equipment ◽  
Radiation Sensitivity ◽  
Case Mix ◽  
Protective Equipment ◽  
X Rays ◽  
X Ray ◽  
Stochastic Effect ◽  
Chest X Ray

Interventional Female Cardiologists (WIC) operating in high case mix laboratories are exposed to a significant chest X-Ray scattered dose from the patient. In this setting stochastic effect may be highly detrimental because of breast radiation sensitivity. Aim of this study is to measure and optimize WICs’ chest radiation exposure in a high case mix electrophysiology laboratory, in order to validate and implement the use of personal protective equipment and lead equivalent glass viewing window, and to evaluate chest X-Ray exposure behind the protective equipment.

Patient Knowledge Regarding Radiation Exposure From Foot and Ankle Imaging

2019 ◽  
Vol 13 (4) ◽  
pp. 324-329 ◽  
Author(s):  
Blaine T. Manning ◽  
Daniel D. Bohl ◽  
Alexander J. P. Idarraga ◽  
George B. Holmes ◽  
Simon Lee ◽  
...  
Keyword(s):  
Ionizing Radiation ◽  
Ct Scan ◽  
Radiation Exposure ◽  
Cone Beam Ct ◽  
Private Insurance ◽  
Cone Beam ◽  
X Rays ◽  
Foot And Ankle ◽  
X Ray ◽  
Imaging Results

Foot and ankle surgeons routinely prescribe diagnostic imaging that exposes patients to potentially harmful ionizing radiation. It is unclear how well patients understand the radiation to which they are exposed. In this study, 946 consecutive new patients were surveyed regarding medical imaging and radiation exposure prior to their first appointment. Respondents compared the amount of radiation associated with chest X-rays (CXRs) with various types of foot and ankle imaging. Results were compared with actual values of radiation exposure from the published literature. Of 946 patients surveyed, 841 (88.9%) participated. Most had private insurance (82.8%) and a bachelor’s degree or higher (60.6%). Most believed that foot X-ray, ankle X-ray, “low dose” foot and ankle computed tomography (CT) scan (alluding to cone-beam CT), and traditional foot and ankle CT scan contain similar amounts of ionizing radiation to CXR. This contradicts the published literature that suggests that the actual exposure to patients is 0.006, 0.006, 0.127, and 0.833 CXR equivalents of radiation, respectively. Of patients who had undergone an X-ray, 55.9% thought about the issue of radiation prior to the study, whereas 46.1% of those undergoing a CT scan considered radiation prior to the exam. Similarly, 35.2% and 27.6% reported their doctor having discussed radiation with them prior to obtaining an X-ray and CT scan, respectively. Patients greatly overestimate the radiation exposure associated with plain film X-rays and cone-beam CT scans of the foot and ankle, and may benefit from increased counseling regarding the relatively low radiation exposure associated with these imaging modalities. Level of Evidence: Level III: Prospective questionnaire

Identification of Crystalline Materials: Classification and Use of X-Ray Diffraction Patterns

1986 ◽  
Vol 1 (1) ◽  
pp. 2-6 ◽  
Author(s):  
J. D. Hanawalt ◽  
H. W. Rinn
Keyword(s):  
Theoretical Basis ◽  
X Rays ◽  
X Ray Diffraction ◽  
Crystalline Materials ◽  
X Ray ◽  
Chemical Company ◽  
The Past ◽  
Different Types ◽  
Diffraction Patterns ◽  
Or Applications

In the course of the past few years, X-ray and spectroscopic methods of analysis have found an increasing usefulness at the Dow Chemical Company. There are a large number of different types of problems on which information can be obtained by the variations of apparatus and technic which are possible in these two fields. It is not the purpose of this paper, however, to discuss these methods or applications in general, but to describe in some detail a scheme of classifying and using X-ray diffraction patterns which has been found very helpful in one particular application of X-rays — namely, that of identifying unknown substances by means of their Hull powder diffraction patterns.The inherent power of X-ray diffraction as a practical means of chemical analysis was pointed out a good many years ago. Having a different theoretical basis and depending upon an entirely different technic than other methods, it would be expected to supplement the information to be obtained from other methods and, at times, to be applicable where other methods are not suitable. It appears, however, that the use of this method has not increased at a rate commensurate with its unique and valuable features, and that it is used by relatively few academic and industrial laboratories.

scholarly journals The corpuscular X-ray spectra of the raio-elements

1933 ◽  
Vol 139 (838) ◽  
pp. 336-342 ◽  
Keyword(s):  
High Frequency ◽  
Photographic Plate ◽  
Correction Term ◽  
X Rays ◽  
X Ray ◽  
Points Of Interest ◽  
Electron Transitions ◽  
Different Types ◽  
Normal Atom ◽  
Narrow Bands

An interesting way in which an excited atom can emit its excess energy has been brought to light by the experiments of Robinson and of Auger. If, for example, an atom is ionised in the K state, then it may emit a quantum of radiation of some line of its K X-ray spectrum by means of a transition of an electron to the K level, but as an alternative method it may emit an electron instead, thus leaving the atom doubly ionised. One such process might be represented as [L I → K, L II → ∝] and the energy E of the ejected electron would be given by E = K abs — L Iabs — L IIabs — δ, where δ is a small correcting term to take into account that the work required to remove an electron from an ionised atom is slightly greater than that necessary in the case of a normal atom. Processes of this kind are essentially different from those giving rise to radiation since two electrons instead of one are concerned in the transition. The entire process must be considered as occurring simultaneously, and, to take as an example the case already mentioned, it has no meaning to attempt to state whether it is an L I electron which goes to the K state, and an L II electron which is ejected or vice versa . Two points of interest in this phenomenon are the investigation of the magnitude of the correction term δ, and of the relative probabilities of the different types of transition. It will be seen later that the possible transitions are considerably more numerous than with single electron transitions which give rise to radiation. This phenomenon has been studied by Robinson by analysing the ejected electrons with a magnetic field. A thin layer of the element under investigation is placed in the position of the source in the well-known semi-circular focussing apparatus, and is irradiated with X-rays of sufficiently high frequency to be able to eject electrons from the K state. There then follows a further electronic emission from these ionised atoms in the manner already described. Both sets of electrons are recorded photographically, and the various groups show up as lines or narrow bands on the photographic plate. A difficulty inherent in the nature of the experiment is that the groups of homogeneous electrons become slightly diffuse in emerging from the target which must have a certain thickness in order to yield groups of reasonable intensity.

Radiation Exposure of Medical Personnel Accompanying the Patient during the Procedure of Superficial X-Ray Therapy of Children

2019 ◽  
Vol 64 (5) ◽  
pp. 54-57
Author(s):  
С. Смолин ◽  
S. Smolin
Keyword(s):  
Radiation Exposure ◽  
Effective Dose ◽  
Dose Rate ◽  
Medical Personnel ◽  
X Rays ◽  
X Ray ◽  
Treatment Room ◽  
Tissue Equivalent ◽  
Tissue Equivalent Phantom ◽  
Irradiation Process

Purpose: Assessment the radiation situation in the treatment room of superficial x-ray therapy during the irradiation process in order to inform about radiation exposure of medical personnel or a relatives. Material and methods: In the course of the study, a procedure of superficial radiotherapy was simulated using a tissue equivalent phantom with sizes 250×250×150 mm. The radiation control protocol of measurements on the Roentgen TA-02 apparatus was compiled on the basis of SanPiN 2.6.1.1192-03. With the help of a clinical dosimeter DKS-AT1123, the ambient dose-rate of short-term x-rays was measured. In accordance with the requirements for conducting radiation monitoring, measurements were taken directly near the apparatus in areas 60×60 cm at points located at heights corresponding to the head level (160 ± 20 cm), chest level (120 ± 20 cm), gonad level (80 ± 20 cm) and the level of the legs (30 ± 20 cm). On the basis of the obtained data, the value of the effective dose-rate of x-ray radiation for the whole human body was calculated for each area. Taking into account the characteristics of the irradiation regime used in the clinic, the total effective dose received by the medical personnel accompanying the patient for the entire course of radiotherapy was calculated. Results: A drawn up diagram is illustrating the radiation situation in the treatment room of superficial radiotherapy. Based on the results of calculations, it can be concluded that the radiation exposure on the accompanying person during superficial x-ray therapy of children’s hemangiomas does not exceed the maximum permissible dose specified in paragraph 5.4.4 of SanPiN 2.6.1.2523-09. Conclusion: In exceptional cases, a parent or medical personnel may be in the treatment room to support the patient.

scholarly journals THE KILLING OF CERTAIN BACTERIA BY X-RAYS

1930 ◽  
Vol 52 (3) ◽  
pp. 435-446 ◽  
Author(s):  
Ralph W. G. Wyckoff
Keyword(s):  
Cell Death ◽  
X Rays ◽  
Sensitive Cell ◽  
Peak Voltage ◽  
X Ray ◽  
Destructive Action ◽  
Air Ionization

Both copper K X-rays and the soft general radiation from a tungsten tube operated at 12 KV kill B. coli and B. aertryke in a linearly exponential fashion. Within the experimental limits, the two organisms appear to be equally sensitive to these radiations. By making use of the fact that X-ray energy is absorbed in quanta, an approximate picture can be formed of the mechanism of this destructive action. If the average numbers of quanta (α) absorbed per bacterium per second are calculated from measurements of air ionization using the quantities outlined in the text, survival ratios for these bacilli can be approximately represented by the equations See PDF for Equation for filtered copper rays and See PDF for Equation for unfiltered copper rays (peak voltage = 34 KV). In terms of the foregoing interpretation this means that when death results, it is caused by the absorption of a single X-ray quantum of energy. Since only about one in twenty of the absorbed quanta kills, the sensitive cell constituents whose destruction leads to cell death must have a volume which is less than 0.06 of the bacterium itself.

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