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Purpose Cement leakage is a typical complication of kyphoplasty for vertebral fractures. It is unclear if cement application intraoperatively can be improved by using other techniques of visualization and which kind of postoperative imaging should be recommended to detect cement extravasation accurately.
Objective To compare the rates of cement leakage detected by intraoperative fluoroscopy, postoperative radiography, and postoperative computed tomography (CT) in a retrospective study.
Patients and Methods The study included 78 patients (60 women and 18 men; 115 vertebral bodies) who were treated with two kinds of kyphoplasty. The patients underwent intraoperative fluoroscopy and postoperative radiography and CT. After surgery, the images were evaluated to compare cement leakage rates and locations in the three visualization techniques. Leakage locations were described as epidural, intradiskal, extravertebral, or intravascular.
Results Compared with CT, intraoperative fluoroscopy regularly detected intradiskal leakage (75%) but had a considerably lower sensitivity for visualizing epidural (21%), extravertebral (31%), and intravascular (51%) cement leakages. A comparison of radiography and CT showed that radiography had a high sensitivity for detecting intradiskal (82%) and intravascular (70%) cement extrusions but a lower sensitivity in identifying epidural (42%) and extravertebral (50%) leaks. Therefore, the CT scan overall was best in detecting location and accuracy.
Conclusion CT detected more cement leaks than any of the other investigated techniques, especially epidural, extravertebral, and intravascular cement leakages. To achieve the best accuracy, only CT provides complete information.

BackgroundChest radiography (CXR) is inferior to Thin-section computed tomography in the detection of asbestos related interstitial and pleural abnormalities. It remains unclear, however, whether these limitations are large enough to impair CXR's ability in detecting the expected reduction in the frequency of these asbestos-related abnormalities (ARA) as exposure decreases.MethodsClinical evaluation, CXR, Thin-section CT and spirometry were obtained in 1418 miners and millers who were exposed to progressively lower airborne concentrations of asbestos. They were separated into four groups according to the type, period and measurements of exposure and/or procedures for controlling exposure: Group I (1940-1966/tremolite and chrysotile, without measurements of exposure and procedures for controlling exposure); Group II (1967-1976/chrysotile only, without measurements of exposure and procedures for controlling exposure); Group III (1977-1980/chrysotile only, initiated measurements of exposure and procedures for controlling exposure) and Group IV (after 1981/chrysotile only, implemented measurements of exposure and a comprehensive procedures for controlling exposure).ResultsIn all groups, CXR suggested more frequently interstitial abnormalities and less frequently pleural plaques than observed on Thin-section CT (p < 0.050). the odds for asbestosis in groups of decreasing exposure diminished to greater extent at Thin-section CT than on CXR. Lung function was reduced in subjects who had pleural plaques evident only on Thin-section CT (p < 0.050). in a longitudinal evaluation of 301 subjects without interstitial and pleural abnormalities on CXR and Thin-section CT in a previous evaluation, only Thin-section CT indicated that these ARA reduced as exposure decreased.ConclusionsCXR compared to Thin-section CT was associated with false-positives for interstitial abnormalities and false-negatives for pleural plaques, regardless of the intensity of asbestos exposure. Also, CXR led to a substantial misinformation of the effects of the progressively lower asbestos concentrations in the occurrence of asbestos-related diseases in miners and millers. ; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) ; Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) ; FUNAPE - Goias State Government ; SAMA ; Brazilian Crysotile Institute (IBC) ; Univ São Paulo, Fac Med, Hosp Clin, Inst Heart,Div Pulm, São Paulo, Brazil ; Univ Estadual Campinas, Fac Ciencias Med, Dept Social & Prevent Med, Occupat Hlth Area, São Paulo, Brazil ; Fac Med Jundiai, Dept Clin Med, São Paulo, Brazil ; Universidade Federal de São Paulo, Escola Paulista Med, Dept Med, Div Resp, São Paulo, Brazil ; Universidade Federal de São Paulo, Escola Paulista Med, Dept Radiol, Div Radiol, São Paulo, Brazil ; Fleury Grp, Div Radiol, São Paulo, Brazil ; Delfin Clin, Dept Radiol, Salvador, BA, Brazil ; Portuguese Hosp, Salvador, BA, Brazil ; Univ British Columbia, Dept Radiol, Vancouver, BC, Canada ; Universidade Federal de São Paulo, Escola Paulista Med, Dept Med, Div Resp, São Paulo, Brazil ; Universidade Federal de São Paulo, Escola Paulista Med, Dept Radiol, Div Radiol, São Paulo, Brazil ; FAPESP: 1996/10415-6 ; CNPq: 420001/2006-9 ; FUNAPE - Goias State Government: 54.023 ; SAMA: 2P-04559-98 ; Web of Science

This work presents an approach to extend the dynamic range of x-ray flat panel detectors by combining two acquisitions of the same sample taken with two different x-ray photon flux levels and the same beam spectral configuration. In order to combine both datasets, the response of detector pixels was modelled in terms of mean and variance using a linear model. The model was extended to take into account the effect of pixel saturation. We estimated a joint probability density function (j-pdf) of the pixel values by assuming that each dataset follows an independent Gaussian distribution. This j-pdf was used for estimating the final pixel value of the high-dynamic-range dataset using a maximum likelihood method. The suitability of the pixel model for the representation of the detector signal was assessed using experimental data from a small-animal cone-beam micro-CT scanner equipped with a flat panel detector. The potential extension in dynamic range offered by our method was investigated for generic flat panel detectors using analytical expressions and simulations. The performance of the proposed dual-exposure approach in realistic imaging environments was compared with that of a regular single-exposure technique using experimental data from two different phantoms. Image quality was assessed in terms of signal-to-noise ratio, contrast, and analysis of profiles drawn on the images. The dynamic range, measured as the ratio between the exposure for saturation and the exposure equivalent to instrumentation noise, was increased from 76.9 to 166.7 when using our method. Dual-exposure results showed higher contrast-to-noise ratio and contrast resolution than the single-exposure acquisitions for the same x-ray dose. In addition, image artifacts were reduced in the combined dataset. This technique to extend the dynamic range of the detector without increasing the dose is particularly suited to image samples that contain both low and high attenuation regions. ; This work was funded by the Innovative Medicines Initiative Joint Undertaking under grant agreement no. 115337, which comprises financial contributions from the European Union's Seventh Framework Programme (FP7/2007-2013) and EFPIA companies' in kind contribution. This work was also partially funded by the AMIT project (CEN-20101014) from the CDTI-CENIT program, projects TEC2010-21619-C04-01, TEC2011-28972-C02-01, and PI11/00616 from the Spanish Ministerio de Ciencia e Innovaci´on. AS is funded by an FPU grant from the Spanish Ministerio de Educación. ; Publicado

Yosra M Alkabab,1 Mushira A Enani,2 Nouf Y Indarkiri,3 Scott K Heysell1 1Department of Medicine, Division of Infectious Diseases and International Health, University of Virginia, Charlottesville, VA, USA; 2Department of Infectious Diseases, King Fahad Medical City, 3Department of Family Medicine, Prince Sultan Military Medical City, Riyadh, Saudi Arabia Background: Prior research suggests that diabetes mellitus (DM) is associated with increasing risk for developing cavitary lung disease in patients with pulmonary tuberculosis (TB). Additionally, chest computed tomography (CT) scan may be more sensitive than chest X-ray in detecting cavitary disease in such patients. The aim of this study was to compare the performance of chest CT to chest X-ray in detecting cavitary lung disease and to compare the frequency of cavities between TB patients with DM and without DM.Patients and methods: We conducted a retrospective cohort study at King Fahad Medical City, Riyadh, Saudi Arabia, from January 2004 to December 2015. We included patients aged 18 years and older with a positive sputum culture for Mycobacterium tuberculosis, and their medical charts were reviewed from admission to discharge.Results: Of the 133 patients who met the inclusion criteria, 38 (28.6%) patients were known to have DM and were compared with 95 (71.4%) patients without DM. DM patients with glycated hemoglobin (HbA1c) >6.5% had significantly more cavitary lesions when compared to all patients (with or without DM) with HbA1c <6.4% and/or random blood sugar <200 mg/dL. Furthermore, CT was able to detect lung cavities in 58.8% of the patients who had negative chest X-ray findings for cavities.Conclusion: The presence of lung cavities was significantly associated with the presence of DM and levels of HbA1c in patients with pulmonary TB. CT scan in those with normal radiography increased the detection of cavities. Keywords: diabetes, pulmonary tuberculosis, lung cavities, computed tomography

A nonuniform distribution of tristructural isotropic (TRISO) particles within a high-temperature gas-cooled reactor (HTGR) pebble may lead to excessive thermal gradients and nonuniform thermal expansion during operation. If the particles are closely clustered, local hotspots may form, leading to excessive stresses on particle layers and an increased probability of particle failure. Although X-ray digital radiography (DR) is currently used to evaluate the TRISO distributions in pebbles, X-ray DR projection images are two-dimensional in nature, which would potentially miss some details for 3D evaluation. This paper proposes a method of 3D visualization and evaluation of the TRISO distribution in HTGR pebbles using cone-beam computed tomography (CBCT): first, a pebble is scanned on our high-resolution CBCT, and 2D cross-sectional images are reconstructed; secondly, all cross-sectional images are restructured to form the 3D model of the pebble; then, volume rendering is applied to segment and display the TRISO particles in 3D for visualization and distribution evaluation. For method validation, several pebbles were scanned and the 3D distributions of the TRISO particles within the pebbles were produced. Experiment results show that the proposed method provides more 3D than DR, which will facilitate pebble fabrication research and production quality control.

The objectives of this study were to evaluate the accuracy of thoracic radiology as a screening test for congenital heart diseases in dogs, to identify the main contributions and limitations of this modality, and to verify the reproducibility of the evaluations by three observers with different levels of training. An interobserver, observational, retrospective and prospective study was carried out, including ninety dogs: thirty healthy animals, thirty with acquired heart diseases and thirty with congenital heart diseases, which all had thoracic radiographs and a confirmed echocardiographic diagnosis. The cases were separated and randomized by a mediator who did not participate in the reading of the radiographic examinations, and no evaluator had access to the patients' data. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of each observer were calculated in relation to the correct classification of dogs to groups of normal or acquired and congenital heart diseases, as well as identification of enlargement of the cardiac silhouette and large vessels of dogs with congenital heart diseases. Finally, the Kappa coefficient was obtained between the observers to verify the reproducibility of the radiological evaluations performed. In general, sensitivity, PPV and accuracy were unsatisfactory ( 70%), and the agreement ranged from poor to reasonable (between 0 and 0.39). Although greater accuracy was achieved in the differentiation of healthy dogs from those with acquired and congenital heart diseases by thoracic radiography, when compared to the other studies, the modality was able only to identify healthy patients, and could not differentiate the individuals with different forms of heart disease or define the cardiac malformations. In addition, there was low reproducibility between observers, therefore, this technique should not be used as a sole screening method in dogs with suspected congenital heart diseases.

Photostimulable storage phosphor (PSP) image acquisition systems have been available for several years. The technology has had the opportunity to mature; however, there has not been an independent comparison of recently marketed commercial systems. For this study, three computed radiography (CR) systems using PSP technology (Kodak CR System 400 with autoloader [Eastman Kodak, Rochester, NY], Fuji FCR AC-3CS [Fuji Medical Systems, Stamford, CT], and Agfa ADC Compact [Bayer Corp, Ridgefield Park, NJ]) were connected to an IBM RadWorks diagnostic radiology workstation (IBM Corp, White Plains NY) and evaluated for conformance to their performance specifications using guidance provided in the most recent draft acceptance testing protocol from Task Group No. 10, American Association of Physicists in Medicine. In addition, the physical requirements (eg, space and power) and connectivity to another manufacturer's diagnostic workstation were examined. X-ray technologist comfort with each PSP imaging system and an assessment by our supporting biomedical equipment maintenance activity of their ability to service each PSP imaging system were also considered.

Radiology services in a combat situation are essentially centred on assisting the battle field physicians/surgeons to save/salvage life and limb. Timely and accurate detection of type and mapping of extent of injury can aid in making imaging based triage which can be of immense help to the treating physicians/trauma surgeons. With the availability of rapid assessment (clinical as well as imaging based) and quick transport facility, the focus has gradually been shifting from merely limb-saving to life-saving strategies. Providing the right imaging modality at the right time for the right patient at the right place is the need of the hour and will dictate the success of combat casualty care. Although there are limitations in terms of terrain and hostility in a combat scenario, newer developments in the field of Radiodiagnosis and imaging can be optimally utilized for better casualty care services. Point of care Digital/Computed Radiography and basic Ultrasonography for trauma complemented by usage of multidetector computed tomography will go a long way in helping timely and accurate management of victims of blast and ballistic injury in a combat scenario. Following a rigid, easy to understand yet comprehensive protocol and radiology reporting system will be invaluable in the combat scenario despite various limitations.

Background: The clavicle, modified long bone, presents morphological and bilateral variations. This may be due to genetic factors, hormones, or environmental and occupational influences. Anthropometric studies in clavicle of Nepalese population using radiograph has not been reported to best of our knowledge. This study, aimed to determine the sexual dimorphism and bilateral asymmetry of clavicle in Nepalese Population using Postero-Anterior Chest X Ray.
Methods: Chest x-rays with normal and clearly visible both clavicles of 1260 Nepalese adults (591 male, 669 female), aged above 20 years were utilized. Inbuilt software "Computed Radiography Fuji Computer System 7" was used for measurements (in centimeter) of sternal head length, acromial end length, mid shaft diameter and length of clavicle. Demarcating point and identification point were calculated. Patients having history of clavicles fractures in the past were excluded.
Results: All the parameters in male is greater than female which is significant except Length/Mid Shaft Diameter. Similarly, all the parameters of right clavicle is significantly greater than left clavicle in both sexes except Sternal Head Length and Mid Shaft Diameter. Demarcating point calculated from length of the clavicle (right >16.17, left >16.10 for male and right <11.20, left <10.65 for female) and Mid Shaft Diameter (right >1.33, left >1.38 for male and right <0.66 and left <0.67 for female) are important parameters to determine sex.
Conclusions:The clavicle shows significant sexual dimorphism and bilateral asymmetry in Nepalese population. The result of this study is helpful to anthropologist and forensic medicine.
Keywords: Anthropometry; clavicle; demarcating point; postero-Anterior chest x-rays; sexual dimorphism

Flat Panel Detectors (FPD) emerge as a next-generation digital x-ray technology. The numerous advantages of flat panel detectors over x-ray film, computed radiography image plates, and image-intensifier tubes are given. They include time efficiency through bypassing chemical processing and the ability to digitally transfer and enhance images. The most important parameters of different technologies are discussed. The comparison table of modern FPD is presented.Emergence and distribution of industrial television, creation of different types of vacuum transfer tubes, in particular for x-ray range, and then and their solid-state analogs promoted use and development the x-ray TV systems of methods of researches. In comparison with radiographic these methods have essential advantages and open essentially new opportunities of researches. With creation and mass introduction of modern computer facilities, in particular her attraction to processes of registration, visualization and processing of shadow x-ray images of objects. Now the special branch is put by x-ray TV systems of pulse action that are widely used in medicine, defectoscopy, military science and different technological processes. Thanks to a number of essential positive qualities (the small weight and dimensions, simplicity of a design, an opportunity of both the panoramic, and directed raying, the low power consumption and also an opportunity to control dynamic objects and processes) devices have received the greatest use in technology of nondestructive control of materials in non-stationary conditions.The device and the scheme of operation of the x-ray electron-optical converter with an axial arrangement of the receiver is considered. As the converter light signal matrixes on the basis of charge-coupled devices, and also CMOS sensors are used. Transformation of x-ray radiation to the image, available to the operator, takes place several stages. At each step of transformations primary information is distorted that leads to deterioration in the visual image. ...

A 42-year-old male presented with dyspnea following a syncopal episode a few hours before admission. He had completed his military service 2 months previously. Electrocardiogram showed a complete heart branch block with severe bradycardia measured at 30 bpm. Imaging included chest radiography, CT scan of the chest, heart and abdomen and MRI of the heart.

A 42-year-old male presented with dyspnea following a syncopal episode a few hours before admission. He had completed his military service 2 months previously. Electrocardiogram showed a complete heart branch block with severe bradycardia measured at 30 bpm. Imaging included chest radiography, CT scan of the chest, heart and abdomen and MRI of the heart.

The first report of a new Coronavirus disease (Covid-19) was in December 2019 and the disease was declared a pandemic by the World Health Organisation (WHO) in March 20201. At this point WHO called on governments to change the course of the outbreak by taking urgent and aggressive action. By the end of April, the number of cases was in excess of 3 million with 211,350 deaths worldwide. Covid-19 is related to previous pandemics - SARS-CoV-1 (SARS) and Middle East respiratory syndrome (MERS)2 and it can be asymptomatic or result in mild to severe symptoms. Unlike influenza it can be contagious before symptoms are apparent3. Due to the highly contagious nature of the disease, rapid and reliable diagnosis is critical. Medical imaging has valuable roles in the diagnosis and management of the Covid-19 patient and radiographers have already started to share their experiences with imaging it45678. Chest computed tomography (CT) has diagnostic value9, though presents challenges including CT availability, the complexity of imaging patients who may be on ventilators and the time taken to decontaminate the CT scanner and room after a Covid-19 patient has used it. For these reasons mobile chest radiography (CXR) has become the most commonly utilised imaging modality for the radiological follow up of lung abnormalities1

AbstractBackgroundDiffuse idiopathic skeletal hyperostosis (DISH) is a potentially serious osteopathic disorder associated with coalescing ossifications of the anterior vertebrae and may be concomitant with a constellation of symptomatology and systemic comorbidities. There is limited dental literature describing this finding on panoramic radiographs and cone beam computed tomography (CBCT) scans.Case presentationsTwo case reports of DISH are provided. One patient manifested extensive ossifications along the cervical vertebrae and consequent episodes of dysphagia and hoarseness. The other affected patient's cervical ossification was found at an earlier stage of formation and without symptomatology. Panoramic radiography, cervical spine radiography, and CBCT examinations have been provided.ConclusionAttending dental healthcare practitioners should carefully evaluate all areas of interest and surrounding fields of view when taking panoramic radiographs and CBCT scans for manifestations of DISH and other potential disorders of the cervical vertebrae. A suspected radiologic finding of DISH should prompt timely referral for comprehensive medical assessment to mitigate neurologic deficits and other comorbidities.