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Sample records for radiographic image standardization

  1. Standardization of thorax, skull and pelvis radiographic images

    International Nuclear Information System (INIS)

    Pina, D.R.; Ghilardi Netto, T.; Trad, C.S.; Brochi, M.A. Corte; Duarte, S.B.; Pina, S.R.

    2001-01-01

    The radiographic techniques for production of chest, skull and pelvis exam were determined for the standard patient. These techniques produced the quality image with smaller dose, for a standard patient, at any conventional X-ray equipment. The radiographic contrast produced for these techniques was measured utilizing the realistic-analytic phantom and classified as an ideal radiographic contrast. This work has the aim to keep the standard of the quality image, for any thickness of patients usually found in clinic routine of the radiodiagnosis service, satisfying the relation risk-benefit for the patient and cost- benefit for the institution. (author)

  2. Construction of a homogeneous phantom for radiographic image standardization

    International Nuclear Information System (INIS)

    Pina, Diana Rodrigues de

    1996-01-01

    The principle of radiodiagnosis consists in the fact the X-ray beam is attenuated at different degrees by distinct tissues. For this reason, the anatomical structures have distinct radiological opacities, that produce the radiographic image. The progresses in radiology are related to the development if new radiographic image formation systems that enable an amplification in the quality, with low dose and/or risk to the patient. The objective of this work is the sensitometric valuation of a screen-film combination, that is still the most used, for the standardization, of radiographic images. Thinking about this, were constructed homogeneous phantoms of the chest, skull and pelvis, for the calibration of X-ray beams, with the purpose of obtaining radiographic images of good quality, basing in the routine of a radiodiagnosis service and in the scientific knowledge. Questions were approached about the choice of the suitable equipment, that allow the obtention of k Vp and m As combinations, to produce radiographic images of good quality, and the reproduction of these combinations to any conventional equipment of diagnostic X-rays. Also presented are the comparison of the doses imparted by these combinations and those used in routine of the Hospital das Clinicas da Faculdade de Medicina de Ribeirao Preto's radiodiagnosis service. (author)

  3. An investigation on comprehensive evaluation and standard of image quality of high voltage chest radiograph

    International Nuclear Information System (INIS)

    Yan Shulin; Li Shuopeng; Zhao Bo; Niu Yantao

    1998-01-01

    Purpose: Based on clinical diagnostic demand, patient irradiation dose and imaging technical parameters, to establish a comprehensive evaluation method and standard in chest radiograph. Methods: (1) From 10 normal chest radiographs, the authors selected the evaluation area on thoracic PA (posteroanterior) radiographs and set up standard for diagnostic demand; (2) Using chest CT scans of 20 males and 20 females, the authors calculated the ratio of lung field to mediastinum; (3) Selecting 100 chest films using 125 kVp, the authors measured the standard density values of each evaluation area; (4) Body surface irradiation doses of 478 normal adults were measured. Results: (1) Based on diagnostic demand, the authors confirmed 7 evaluation areas and 4 physical evaluation factors. At the same time, evaluation standards were obtained; (2) Comprehensive evaluation methods were established; (3) Standard height, weight and body surface irradiation dose of Chinese normal adults were investigated preliminarily. Conclusion: Based on the concept of comprehensive evaluation, investigation on the evaluation methods and standard in chest PA radiograph was carried out which might be taken as the foundation for future approach on nation-wide basis

  4. Assessment of Radiographic Image Quality by Visual Examination of Neutron Radiographs of the Calibration Fuel Pin

    DEFF Research Database (Denmark)

    Domanus, Joseph Czeslaw

    1986-01-01

    Up till now no reliable radiographic image quality standards exist for neutron radiography of nuclear reactor fuel. Under the Euratoro Neutron Radiography Working Group (NRWG) Test Program neutron radiographs were produced at different neutron radiography facilities within the European Community...... of a calibration fuel pin. The radiographs were made by the direct, transfer and tracketch methods using different film recording materials. These neutron radiographs of the calibration fuel pin were used for the assessement of radiographic image quality. This was done by visual examination of the radiographs...

  5. Three-dimensional hindfoot alignment measurements based on biplanar radiographs: comparison with standard radiographic measurements

    International Nuclear Information System (INIS)

    Sutter, Reto; Pfirrmann, Christian W.A.; Buck, Florian M.; Espinosa, Norman

    2013-01-01

    To establish a hindfoot alignment measurement technique based on low-dose biplanar radiographs and compare with hindfoot alignment measurements on long axial view radiographs, which is the current reference standard. Long axial view radiographs and low-dose biplanar radiographs of a phantom consisting of a human foot skeleton embedded in acrylic glass (phantom A) and a plastic model of a human foot in three different hindfoot positions (phantoms B1-B3) were imaged in different foot positions (20 internal to 20 external rotation). Two independent readers measured hindfoot alignment on long axial view radiographs and performed 3D hindfoot alignment measurements based on biplanar radiographs on two different occasions. Time for three-dimensional (3D) measurements was determined. Intraclass correlation coefficients (ICC) were calculated. Hindfoot alignment measurements on long axial view radiographs were characterized by a large positional variation, with a range of 14 /13 valgus to 22 /27 varus (reader 1/2 for phantom A), whereas the range of 3D hindfoot alignment measurements was 7.3 /6.0 to 9.0 /10.5 varus (reader 1/2 for phantom A), with a mean and standard deviation of 8.1 ± 0.6/8.7 ± 1.4 respectively. Interobserver agreement was high (ICC = 0.926 for phantom A, and ICC = 0.886 for phantoms B1-B3), and agreement between different readouts was high (ICC = 0.895-0.995 for reader 1, and ICC = 0.987-0.994 for reader 2) for 3D measurements. Mean duration of 3D measurements was 84 ± 15/113 ± 15 s for reader 1/2. Three-dimensional hindfoot alignment measurements based on biplanar radiographs were independent of foot positioning during image acquisition and reader independent. In this phantom study, the 3D measurements were substantially more precise than the standard radiographic measurements. (orig.)

  6. Standard practice for determining relative image quality response of industrial radiographic imaging systems

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2007-01-01

    1.1 This standard provides a practice whereby industrial radiographic imaging systems may be comparatively assessed using the concept of relative image quality response (RIQR). The RIQR method presented within this practice is based upon the use of equivalent penetrameter sensitivity (EPS) described within Practice E 1025 and subsection 5.2 of this practice. Figure 1 illustrates a relative image quality indicator (RIQI) that has four different steel plaque thicknesses (.015, .010, .008, and .005 in.) sequentially positioned (from top to bottom) on a ¾-in. thick steel plate. The four plaques contain a total of 14 different arrays of penetrameter-type hole sizes designed to render varied conditions of threshold visibility ranging from 1.92 % EPS (at the top) to .94 % EPS (at the bottom) when exposed to nominal 200 keV X-ray radiation. Each “EPS” array consists of 30 identical holes; thus, providing the user with a quantity of threshold sensitivity levels suitable for relative image qualitative response com...

  7. Radiographic imaging. 4 ed.

    International Nuclear Information System (INIS)

    Chesney, D.N.; Chesney, M.O.

    1981-01-01

    This is a revised edition of the textbook previously entitled 'Radiographic Photography' and accords with the current syllabus of training for the Diploma of the Royal College of Radiographers. The aim is a non-mathematical approach to provide a guide for the student to the knowledge and understanding of the theoretical concepts which affect the quality of radiographic image; materials and practices are also reviewed, particularly in relation to the characteristics of the radiographic image, and to processing equipment and processing areas. The subject is dealt with under the following headings: the photographic process, film materials in x-ray departments, sensitometry, storage of film materials and radiographs, intensifying screens and cassettes, film processing, developing, fixing, rinsing, washing, drying, the processing area and equipment, systems for daylight film handling, the radiographic image, management of the quality, presentation of the radiograph, light images and their recording, fluorography, some special imaging processes, e.g. xerography, copying radiographs. (U.K.)

  8. Digital subtraction radiographic evaluation of the standardize periapical intraoral radiographs

    International Nuclear Information System (INIS)

    Cho, Bong Hae; Nah, Kyung Soo

    1993-01-01

    The geometrically standardized intraoral radiographs using 5 occlusal registration material were taken serially from immediate, 1 day, 2, 4, 8, 12 and 16 weeks after making the bite blocks. The qualities of those subtracted images were evaluated to check the degree of reproducibility of each impression material. The results were as follows: 1. The standard deviations of the grey scales of the overall subtracted images were 4.9 for Exaflex, 7.2 for Pattern resin, 9.0 for Tooth Shade Acrylic, 12.2 for XCP only, 14.8 for Impregum. 2. The standard deviation of the grey scales of the overall subtracted images were grossly related to those of the localized horizontal line of interest. 3. Exaflex which showed the best subtracted image quality had 15 cases of straight, 14 cases of wave, 1 case of canyon shape. Impregum which showed the worst subtracted image quality had 4 cases of straight, 8 cases of wave, 18 cases of canyon shape respectively.

  9. Sensitometric properties and image quality of radiographic film and paper

    International Nuclear Information System (INIS)

    Domanus, J.C.

    1985-09-01

    When using X-ray film or radiographic paper for industrial applications one is interested in knowing not only their sensitometric properties (such as speed and contrast) but also the image quality obtainable with a particular brand of film or paper. Although standard methods for testing both properties separately are available it is desirable that the method permits the assessment of all the relevant properties together. The sensitometric properties are usually determined at constant kilovoltage and filtration at the X-ray tube, whereas radiographic image thicknesses. The use of the constant exposure technique could be used to compare both the sensitometric properties as well as the image quality for different radiographic materials. It consist of exposing different film or paper brands at a chosen, constant mAmin exposure when testing radiographic image quality for different thicknesses of a given material. From the results obtained with the constant exposure technique conclusions are drawn about its applicability as a standard method for assessing radiographic film and paper. (author)

  10. Standardized radiographic interpretation of thoracic tuberculosis in children

    International Nuclear Information System (INIS)

    Concepcion, Nathan David P.; Laya, Bernard F.; Andronikou, Savvas; Daltro, Pedro A.N.; Sanchez, Marion O.; Uy, Jacqueline Austine U.; Lim, Timothy Reynold U.

    2017-01-01

    There is a lack of standardized approach and terminology to classify the diverse spectrum of manifestations in tuberculosis. It is important to recognize the different clinical and radiographic patterns to guide treatment. As a result of changing epidemiology, there is considerable overlap in the radiologic presentations of primary tuberculosis and post-primary tuberculosis. In this article we promote a standardized approach in clinical and radiographic classification for children suspected of having or diagnosed with childhood tuberculosis. We propose standardized terms to diminish confusion and miscommunication, which can affect management. In addition, we present pitfalls and limitations of imaging. (orig.)

  11. Standardized radiographic interpretation of thoracic tuberculosis in children

    Energy Technology Data Exchange (ETDEWEB)

    Concepcion, Nathan David P.; Laya, Bernard F. [St. Luke' s Medical Center, Section of Pediatric Radiology, Institute of Radiology, Taguig City (Philippines); St. Luke' s Medical Center, Section of Pediatric Radiology, Institute of Radiology, Quezon City (Philippines); Andronikou, Savvas [Bristol Royal Hospital for Children and the University of Bristol, Department of Paediatric Radiology, Bristol (United Kingdom); Daltro, Pedro A.N. [Clinica de Diagnostico por Imagem, Section of Pediatric Radiology, Rio de Janeiro (Brazil); Sanchez, Marion O. [St. Luke' s Medical Center, Section of Pediatric Pulmonology, Institute of Pulmonary Medicine, Quezon City (Philippines); Uy, Jacqueline Austine U. [St. Luke' s Medical Center, Section of Pediatric Radiology, Institute of Radiology, Taguig City (Philippines); Lim, Timothy Reynold U. [St. Luke' s Medical Center, Section of Pediatric Radiology, Institute of Radiology, Quezon City (Philippines)

    2017-09-15

    There is a lack of standardized approach and terminology to classify the diverse spectrum of manifestations in tuberculosis. It is important to recognize the different clinical and radiographic patterns to guide treatment. As a result of changing epidemiology, there is considerable overlap in the radiologic presentations of primary tuberculosis and post-primary tuberculosis. In this article we promote a standardized approach in clinical and radiographic classification for children suspected of having or diagnosed with childhood tuberculosis. We propose standardized terms to diminish confusion and miscommunication, which can affect management. In addition, we present pitfalls and limitations of imaging. (orig.)

  12. Standardized radiographic interpretation of thoracic tuberculosis in children.

    Science.gov (United States)

    Concepcion, Nathan David P; Laya, Bernard F; Andronikou, Savvas; Daltro, Pedro A N; Sanchez, Marion O; Uy, Jacqueline Austine U; Lim, Timothy Reynold U

    2017-09-01

    There is a lack of standardized approach and terminology to classify the diverse spectrum of manifestations in tuberculosis. It is important to recognize the different clinical and radiographic patterns to guide treatment. As a result of changing epidemiology, there is considerable overlap in the radiologic presentations of primary tuberculosis and post-primary tuberculosis. In this article we promote a standardized approach in clinical and radiographic classification for children suspected of having or diagnosed with childhood tuberculosis. We propose standardized terms to diminish confusion and miscommunication, which can affect management. In addition, we present pitfalls and limitations of imaging.

  13. ASTM reference radiologic digital image standards

    International Nuclear Information System (INIS)

    Wysnewski, R.; Wysnewski, D.

    1996-01-01

    ASTM Reference Radiographs have been essential in defining industry's material defect grade levels for many years. ASTM Reference Radiographs are used extensively as even the American Society for Metals Nondestructive Inspection and Quality Control Metals Handbook, Volume 11, eighth edition refers to ASTM Standard Reference Radiographs. The recently published E 1648 Standard Reference Radiographs for Examination of Aluminum Fusion Welds is a prime example of the on-going need for these references. To date, 14 Standard Reference Radiographs have been published to characterize material defects. Standard Reference Radiographs do not adequately address film-less radiologic methods. There are differences in mediums to content with. On a computer CRT defect indications appear differently when compared to indications viewed in a radiograph on a view box. Industry that uses non-film radiologic methods of inspection can be burdened with additional time and money developing internal standard reference radiologic images. These references may be deemed necessary for grading levels of product defects. Because there are no ASTM Standard Reference Radiologic data files for addressing this need in the industry, the authors of this paper suggested implementing a method for their creation under ASTM supervision. ASTM can assure continuity to those users making the transition from analog radiographic images to digital image data by swiftly addressing the requirements for reference digital image standards. The current status and possible future activities regarding a method to create digital data files is presented in this paper summary

  14. The radiographic image: A cultural artefact?

    International Nuclear Information System (INIS)

    Strudwick, Ruth M.

    2014-01-01

    This article looks at the role of the radiographic images produced by diagnostic radiographers. An ethnographic study of the workplace culture in one diagnostic imaging department was undertaken using participant observation for four months and semi-structured interviews with ten key informants. One of the key themes; that of the radiographic image as a cultural artefact, is explored in this article. The radiographic image is a cultural artefact which radiographers are protective of and take ownership of. Radiographers are conscious of the quality of their images and the images are an important aspect of their work. Radiographers take criticism of their images personally. The radiographic image is a record of the interaction that occurs between the radiographer and the patient. The way in which radiographic images are viewed, used and judged is an important aspect of the role of diagnostic radiographer

  15. Construction of a homogeneous phantom for radiographic image standardization; Construcao de um fantoma homogeneo para padronizacao de imagens radiograficas

    Energy Technology Data Exchange (ETDEWEB)

    Pina, Diana Rodrigues de

    1996-12-31

    The principle of radiodiagnosis consists in the fact the X-ray beam is attenuated at different degrees by distinct tissues. For this reason, the anatomical structures have distinct radiological opacities, that produce the radiographic image. The progresses in radiology are related to the development if new radiographic image formation systems that enable an amplification in the quality, with low dose and/or risk to the patient. The objective of this work is the sensitometric valuation of a screen-film combination, that is still the most used, for the standardization, of radiographic images. Thinking about this, were constructed homogeneous phantoms of the chest, skull and pelvis, for the calibration of X-ray beams, with the purpose of obtaining radiographic images of good quality, basing in the routine of a radiodiagnosis service and in the scientific knowledge. Questions were approached about the choice of the suitable equipment, that allow the obtention of k Vp and m As combinations, to produce radiographic images of good quality, and the reproduction of these combinations to any conventional equipment of diagnostic X-rays. Also presented are the comparison of the doses imparted by these combinations and those used in routine of the Hospital das Clinicas da Faculdade de Medicina de Ribeirao Preto`s radiodiagnosis service. (author) 24 refs., 27 figs., 12 tabs.

  16. Chesneys' radiographic imaging. 5. ed.

    International Nuclear Information System (INIS)

    Ball, J.; Price, T.

    1989-01-01

    This new edition of Chesney and Chesney: Radiographic Imaging has been completely written by two new authors. The book reflects the change in emphasis in radiology from photographic processes towards electronic imaging methods. There is new material on image intensifiers and television imaging, digital imaging and digital subtractions. Analyses of the various characteristics of, and defects in, images on radiographs, xeroradiographs and the television screen are included. The methods, equipment and materials used to record the cathode ray tube image are described and there is new material on the principles of alternative diagnostic imaging techniques such as ultrasound, computed tomography and radionuclide imaging which provide cathode ray tube images. The book is primarily for student radiographers studying for the Diploma of the College of Radiographers, but radiographers studying for postdiplomate qualifications such as the Higher Diploma (HDCR) will also find the book helpful. (author)

  17. Producing quality radiographic images

    International Nuclear Information System (INIS)

    Cullinan, A.M.

    1987-01-01

    This book gives an overview of physics, equipment, imaging, and quality assurance in the radiology department. The chapters are laid out with generous use of subheads to allow for quick reference, Points are illustrated with clear, uncluttered line diagrams and well-produced images. The accompanying explanations are miniature lessons by themselves. Inserted at various points throughout the text are important notes that highlight key concepts. The chapter ''Image Evaluation and Application of Radiographic Principles'' present a systematic approach to evaluating radiographs and contains several sample radiographs to illustrate the points made

  18. Digital image analysis of NDT radiographs

    International Nuclear Information System (INIS)

    Graeme, W.A. Jr.; Eizember, A.C.; Douglass, J.

    1989-01-01

    Prior to the introduction of Charge Coupled Device (CCD) detectors the majority of image analysis performed on NDT radiographic images was done visually in the analog domain. While some film digitization was being performed, the process was often unable to capture all the usable information on the radiograph or was too time consuming. CCD technology now provides a method to digitize radiographic film images without losing the useful information captured in the original radiograph in a timely process. Incorporating that technology into a complete digital radiographic workstation allows analog radiographic information to be processed, providing additional information to the radiographer. Once in the digital domain, that data can be stored, and fused with radioscopic and other forms of digital data. The result is more productive analysis and management of radiographic inspection data. The principal function of the NDT Scan IV digital radiography system is the digitization, enhancement and storage of radiographic images

  19. Digital image processing of periapical radiographs with low dose of radiation

    International Nuclear Information System (INIS)

    Kerbauy, Warley David; Moraes, Luiz Cesar de

    1996-01-01

    The aim of the study was to evaluate whether digitized images obtained from peri apical radiographs taken with low dose of radiation could be improved with the aid of a computer software (Photo Styler) for digital treatment. Serial and standardized radiographs of molar and pre molar areas were studied. A total of 57 images equivalent to the radiographs taken with reduced exposure time (60 and 80% of the time considered normal), digitized and treated, were submitted to the evaluation of seven examiners which compared them with those images without treatment. It was verified that about 80% of the images equivalent to the radiographs taken with 60% reduction of ordinary exposure time were considered to having quality for supporting diagnosis. As for the images taken with 80% reduction of ordinary exposure time, about 50% of them were considered suitable for the same purpose. (author)

  20. Radiographical measurements for distal intra-articular fractures of the radius using plain radiographs and cone beam computed tomography images

    Energy Technology Data Exchange (ETDEWEB)

    Suojaervi, Nora; Lindfors, N. [Helsinki University Central Hospital, Department of Hand Surgery, Helsinki (Finland); Sillat, T.; Koskinen, S.K. [HUS Helsinki Medical Imaging Center, Helsinki University Central Hospital, Department of Radiology, Helsinki (Finland)

    2015-12-15

    Operative treatment of an intra-articular distal radius fracture is one of the most common procedures in orthopedic and hand surgery. The intra- and interobserver agreement of common radiographical measurements of these fractures using cone beam computed tomography (CBCT) and plain radiographs were evaluated. Thirty-seven patients undergoing open reduction and volar fixation for a distal radius fracture were studied. Two radiologists analyzed the preoperative radiographs and CBCT images. Agreement of the measurements was subjected to intra-class correlation coefficient and the Bland-Altman analyses. Plain radiographs provided a slightly poorer level of agreement. For fracture diastasis, excellent intraobserver agreement was achieved for radiographs and good or excellent agreement for CBCT, compared to poor interobserver agreement (ICC 0.334) for radiographs and good interobserver agreement (ICC 0.621) for CBCT images. The Bland-Altman analyses indicated a small mean difference between the measurements but rather large variation using both imaging methods, especially in angular measurements. For most of the measurements, radiographs do well, and may be used in clinical practice. Two different measurements by the same reader or by two different readers can lead to different decisions, and therefore a standardization of the measurements is imperative. More detailed analysis of articular surface needs cross-sectional imaging modalities. (orig.)

  1. Radiographical measurements for distal intra-articular fractures of the radius using plain radiographs and cone beam computed tomography images.

    Science.gov (United States)

    Suojärvi, Nora; Sillat, T; Lindfors, N; Koskinen, S K

    2015-12-01

    Operative treatment of an intra-articular distal radius fracture is one of the most common procedures in orthopedic and hand surgery. The intra- and interobserver agreement of common radiographical measurements of these fractures using cone beam computed tomography (CBCT) and plain radiographs were evaluated. Thirty-seven patients undergoing open reduction and volar fixation for a distal radius fracture were studied. Two radiologists analyzed the preoperative radiographs and CBCT images. Agreement of the measurements was subjected to intra-class correlation coefficient and the Bland-Altman analyses. Plain radiographs provided a slightly poorer level of agreement. For fracture diastasis, excellent intraobserver agreement was achieved for radiographs and good or excellent agreement for CBCT, compared to poor interobserver agreement (ICC 0.334) for radiographs and good interobserver agreement (ICC 0.621) for CBCT images. The Bland-Altman analyses indicated a small mean difference between the measurements but rather large variation using both imaging methods, especially in angular measurements. For most of the measurements, radiographs do well, and may be used in clinical practice. Two different measurements by the same reader or by two different readers can lead to different decisions, and therefore a standardization of the measurements is imperative. More detailed analysis of articular surface needs cross-sectional imaging modalities.

  2. Acquired image quality in digital industrial radiographic equipments

    International Nuclear Information System (INIS)

    Oliveira, Cristiane de Queiroz; Lopes, Ricardo Tadeu; Oliveira, Davi F.

    2008-01-01

    The computerized radiographic application in the industrial area is a recent event. The imaging plate is the equipment used as imaging receiver during the exposition radiographic technique, which consists of a flexible photostimulable phosphor screen, capable of storing the photons energy of the incident X and γ rays and of a reading unit which uses a laser device to stimulate a visible light. As two types of phosphor screen are manufactured, one for general use (General Plate - GP) and another one for specific using (High Resolution-HR), one of the objectives of this study was to evaluate the spatial resolution capability in both plates using the Kodak equipment. Furthermore, equipment from different makers, Kodak and General Electric Company - GE, were compared. Two phosphor screen HR were used as the main objective of this study. Imaging Quality Indicators - IQI were used to evaluate the spatial resolution of the images in accordance with ASME and DIN standard. The results show that after evaluating the GP and HR Kodak plates, the HR plate was capable of showing a larger resolution of details. However, after evaluating the performance of the HR Kodak plate and GE plate, over the same acquisition condition and with the same size of the laser focal set of 87 μm, the results show a superiority in the GE equipment used for industrial radiographic, mainly for processed images in each specific ambient of digital processing and its performance in meeting satisfactorily the ASME code and the DIN standard. (author)

  3. Quality of the radiographic image in paper radiography

    International Nuclear Information System (INIS)

    Domanus, J.C.; El Fouly, H.M.

    1981-09-01

    The quality of the radiographic image was investigated by the use of standard ISO wire Image Quality Indicators and ASTM Penetrameters. 10, 20, and 30 mm thick welds on alumunium and steel plates were radiographed using X-ray machines with voltages from 35 to 300 kV. Agfa-Gevaert Structurix IC paper with Structurix IC screens Type II as well as Kodak Industrex 600 and 620 and Rapid 700 paper with Fl and F2 screens were used throughout the investigation. The results reached for radiographic paper were compared with those for a fast X-ray film (Kodak Industrex D). The results of the investigation were presented at the International Conference Joining of Metals JOM-1 in Elsinore, Denmark (9-12.8.1981) and at the Second European Conference on Non-Destructive Testing in Vienna (14-16.9.1981). The texts of both papers are reproduced in this report. (author)

  4. Two-Dimensional Image Fusion of Planar Bone Scintigraphy and Radiographs in Patients with Clinical Scaphoid Fracture: An Imaging Study

    DEFF Research Database (Denmark)

    Henriksen, O.M.; Lonsdale, M.N.; Jensen, T.D.

    2008-01-01

    . Bone scintigraphy is highly sensitive for the detection of fractures, but exact localization of scintigraphic lesions may be difficult and can negatively affect diagnostic accuracy. Purpose: To investigate the influence of image fusion of planar bone scintigraphy and radiographs on image interpretation......Background: Although magnetic resonance imaging (MRI) is now considered the gold standard in second-line imaging of patients with suspected scaphoid fracture and negative radiographs, bone scintigraphy can be used in patients with pacemakers, metallic implants, or other contraindications to MRI....... Conclusion: Image fusion of planar bone scintigrams and radiographs has a significant influence on image interpretation and increases both diagnostic confidence and interobserver agreement Udgivelsesdato: 2008/12/3...

  5. Two-dimensional fusion imaging of planar bone scintigraphy and radiographs in patients with clinical scaphoid fracture: an imaging study

    DEFF Research Database (Denmark)

    Henriksen, Otto Mølby; Lonsdale, Markus Georg; Jensen, T D

    2009-01-01

    . Bone scintigraphy is highly sensitive for the detection of fractures, but exact localization of scintigraphic lesions may be difficult and can negatively affect diagnostic accuracy. PURPOSE: To investigate the influence of image fusion of planar bone scintigraphy and radiographs on image interpretation......BACKGROUND: Although magnetic resonance imaging (MRI) is now considered the gold standard in second-line imaging of patients with suspected scaphoid fracture and negative radiographs, bone scintigraphy can be used in patients with pacemakers, metallic implants, or other contraindications to MRI....... CONCLUSION: Image fusion of planar bone scintigrams and radiographs has a significant influence on image interpretation and increases both diagnostic confidence and interobserver agreement....

  6. Sensitometric properties and image quality of radiographic film and paper

    International Nuclear Information System (INIS)

    Domanus, J.C.

    1985-01-01

    When using X-ray film or radiographic paper for industrial applications one is interested in knowing not only their sensitometric properties (such as speed and contrast) but also the image quality obtainable with a particular brand of film or paper. Although standard methods for testing sensitometric properties and image quality separately are available, it is desirable to find a method by the use of which all the relevant properties could be tested together. The sensitometric properties are usually determined at constant kilovoltage and filtration at the X-ray tube, whereas the radiographic image quality is tested at different kilovoltages and for different material thicknesses

  7. Standard digital reference images for titanium castings

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 The digital reference images provided in the adjunct to this standard illustrate various types and degrees of discontinuities occurring in titanium castings. Use of this standard for the specification or grading of castings requires procurement of the adjunct digital reference images, which illustrate the discontinuity types and severity levels. They are intended to provide the following: 1.1.1 A guide enabling recognition of titanium casting discontinuities and their differentiation both as to type and degree through digital radiographic examination. 1.1.2 Example digital radiographic illustrations of discontinuities and a nomenclature for reference in acceptance standards, specifications and drawings. 1.2 The digital reference images consist of seventeen digital files each illustrating eight grades of increasing severity. The files illustrate seven common discontinuity types representing casting sections up to 1-in. (25.4-mm). 1.3 The reference radiographs were developed for casting sections up to 1...

  8. [Transparency regime: semiotics of radiographical images in urological diagnostics].

    Science.gov (United States)

    Martin, M; Fangerau, H

    2012-10-01

    Shortly after Röntgen discovered x-rays urology became one of the main test fields for the application of this new technology. Initial scepticism among physicians, who were inclined to cling to traditional manual methods of diagnosing, was replaced by enthusiasm for radiographic technologies and the new method soon became the standard in, for example the diagnosis of concrements. Patients favoring radiographic procedures over the use of probes and a convincing documentation of stones in radiograms were factors that impacted the relatively rapid integration of radiology into urology. The radiographic representation of soft tissues and body cavities was more difficult and the development of contrast agents in particular posed a serious problem. Several patients died during this research. A new diagnostic dimension was revealed when radiography and cystography were combined to form the method of retrograde pyelography. However, the problem of how urologists could learn how to read the new images remained. In order to allow trainee physicians to practice interpreting radiograms atlases were produced which offered explanatory texts and drawings for radiographic images of the kidneys, the bladder etc. Thus, urologists developed a self-contained semiotics which facilitated the appropriation of a unique urological radiographical gaze.

  9. Measure by image analysis of industrial radiographs

    International Nuclear Information System (INIS)

    Brillault, B.

    1988-01-01

    A digital radiographic picture processing system for non destructive testing intends to provide the expert with computer tool, to precisely quantify radiographic images. The author describes the main problems, from the image formation to its characterization. She also insists on the necessity to define a precise process in order to automatize the system. Some examples illustrate the efficiency of digital processing for radiographic images [fr

  10. Image rejects/retakes-radiographic challenges

    International Nuclear Information System (INIS)

    Waaler, D.; Hofmann, B.

    2010-01-01

    A general held position among radiological personnel prior to digitalisation was that the problem of image rejects/retakes should more or less vanish. However, rejects/retakes still impose several challenges within radiographic imaging; they occupy unnecessary resources, expose patients to unnecessary ionizing radiation and may also indicate suboptimal quality management. The latter is the main objective of this paper, which is based on a survey of international papers published both for screen/film and digital technology. The digital revolution in imaging seems to have reduced the percentage of image rejects/retakes from 10-15 to 3-5%. The major contribution to the decrease appears to be the dramatic reduction of incorrect exposures. At the same time, rejects/retakes due to lack of operator competence (positioning, etc.) are almost unchanged, or perhaps slightly increased (due to lack of proper technical competence, incorrect organ coding, etc.). However, the causes of rejects/retakes are in many cases defined and reported with reference to radiographers' subjective evaluations. Thus, unless radiographers share common views on image quality and acceptance criteria, objective measurements and assessments of reject/retake rates are challenging tasks. Interestingly, none of the investigated papers employs image quality parameters such as 'too much noise' as categories for rejects/retakes. Surprisingly, no reject/retake analysis seems yet to have been conducted for direct digital radiography departments. An increased percentage of rejects/retakes is related to 'digital skills' of radiographers and therefore points to areas for extended education and training. Furthermore, there is a need to investigate the inter subjectivity of radiographers' perception of, and attitude towards, both technical and clinical image quality criteria. Finally, there may be a need to validate whether reject/retake rate analysis is such an effective quality indicator as has been asserted

  11. Image rejects/retakes--radiographic challenges.

    Science.gov (United States)

    Waaler, D; Hofmann, B

    2010-01-01

    A general held position among radiological personnel prior to digitalisation was that the problem of image rejects/retakes should more or less vanish. However, rejects/retakes still impose several challenges within radiographic imaging; they occupy unnecessary resources, expose patients to unnecessary ionizing radiation and may also indicate suboptimal quality management. The latter is the main objective of this paper, which is based on a survey of international papers published both for screen/film and digital technology. The digital revolution in imaging seems to have reduced the percentage of image rejects/retakes from 10-15 to 3-5 %. The major contribution to the decrease appears to be the dramatic reduction of incorrect exposures. At the same time, rejects/retakes due to lack of operator competence (positioning, etc.) are almost unchanged, or perhaps slightly increased (due to lack of proper technical competence, incorrect organ coding, etc.). However, the causes of rejects/retakes are in many cases defined and reported with reference to radiographers' subjective evaluations. Thus, unless radiographers share common views on image quality and acceptance criteria, objective measurements and assessments of reject/retake rates are challenging tasks. Interestingly, none of the investigated papers employs image quality parameters such as 'too much noise' as categories for rejects/retakes. Surprisingly, no reject/retake analysis seems yet to have been conducted for direct digital radiography departments. An increased percentage of rejects/retakes is related to 'digital skills' of radiographers and therefore points to areas for extended education and training. Furthermore, there is a need to investigate the inter-subjectivity of radiographers' perception of, and attitude towards, both technical and clinical image quality criteria. Finally, there may be a need to validate whether reject/retake rate analysis is such an effective quality indicator as has been asserted.

  12. Contribution to identification of factors causing radiographic image unsharpness

    International Nuclear Information System (INIS)

    Branzan, C.; Popescu, A.; Radu, R.

    1995-01-01

    Radiographic image quality is crucial for the ability of the radiographic method to give us a maximum information about the macroscopic structure of materials and pieces, investigated by penetrating radiation. Radiographic image quality depends on several factors. A high quality image is able to show small and typical defects. One of the most important factor affecting radiographic image is unsharpness. The total effective unsharpness of the film must be some function of several factors and their contribution is taken into account by summing up different kinds of unsharpness: geometric unsharpness, internal unsharpness, screen unsharpness, and accidental unsharpness. This work analyses the weight of the radiographic image unsharpness and the possibilities for determining its influence on the quality of the radiographic image. (author)

  13. Reject analysis: A comparison of radiographer and radiologist perceptions of image quality

    International Nuclear Information System (INIS)

    Mount, J.

    2016-01-01

    This study explores the potential differences in perceptions of image quality between radiographers and radiologists in a large UK hospital and the subsequent impact this has on image rejection. Image rejection, while sometimes necessary, often leads to an increased radiation dose to the patient due to the need to repeat. Moreover, this translates into increased waiting times, departmental costs, and lower patient satisfaction. Adopting a mixed methods approach, this paper first seeks to quantify the differences in radiographer and radiologist perceptions and second establish the underlying causes of such differences through a quantitative and qualitative investigation respectively. Using a standardized psychometric scale of a GP lateral knee, the study reveals significant differences in the perceptions of quality and rejection rates between radiographers and radiologists driven by a conflict in the evaluation criteria used. The study has significant implications for improving departmental performance and proposes a potential solution for reducing reject rates and image repeats. - Highlights: • Significant differences are found to exist in perceptions of image quality. • Differences in perceptions of image quality directly influence reject rates. • Radiographers judge images on technical criteria. • Radiologists judge images on diagnostic criteria. • Results suggest better communication could reduce reject rates.

  14. Black Lung Benefits Act: standards for chest radiographs. Final rule.

    Science.gov (United States)

    2014-04-17

    Physicians and adjudicators use chest radiographs (X-rays) as a tool in evaluating whether a coal miner suffers from pneumoconiosis (black lung disease). Accordingly, the Department's regulations implementing the Black Lung Benefits Act allow the submission of radiographs in connection with benefit claims and set out quality standards for administering and interpreting film-based chest radiographs. This final rule updates the Department's existing film-radiograph standards and provides parallel standards for digital radiographs. This rule also updates outdated terminology and removes certain obsolete provisions.

  15. Transfer function analysis of radiographic imaging systems

    International Nuclear Information System (INIS)

    Metz, C.E.; Doi, K.

    1979-01-01

    The theoretical and experimental aspects of the techniques of transfer function analysis used in radiographic imaging systems are reviewed. The mathematical principles of transfer function analysis are developed for linear, shift-invariant imaging systems, for the relation between object and image and for the image due to a sinusoidal plane wave object. The other basic mathematical principle discussed is 'Fourier analysis' and its application to an input function. Other aspects of transfer function analysis included are alternative expressions for the 'optical transfer function' of imaging systems and expressions are derived for both serial and parallel transfer image sub-systems. The applications of transfer function analysis to radiographic imaging systems are discussed in relation to the linearisation of the radiographic imaging system, the object, the geometrical unsharpness, the screen-film system unsharpness, other unsharpness effects and finally noise analysis. It is concluded that extensive theoretical, computer simulation and experimental studies have demonstrated that the techniques of transfer function analysis provide an accurate and reliable means for predicting and understanding the effects of various radiographic imaging system components in most practical diagnostic medical imaging situations. (U.K.)

  16. Large Format Radiographic Imaging

    International Nuclear Information System (INIS)

    Rohrer, J. S.; Stewart, Lacey; Wilke, M. D.; King, N. S.; Baker A, S.; Lewis, Wilfred

    1999-01-01

    Radiographic imaging continues to be a key diagnostic in many areas at Los Alamos National Laboratory (LANL). Radiographic recording systems have taken on many form, from high repetition-rate, gated systems to film recording and storage phosphors. Some systems are designed for synchronization to an accelerator while others may be single shot or may record a frame sequence in a dynamic radiography experiment. While film recording remains a reliable standby in the radiographic community, there is growing interest in investigating electronic recording for many applications. The advantages of real time access to remote data acquisition are highly attractive. Cooled CCD camera systems are capable of providing greater sensitivity with improved signal-to-noise ratio. This paper begins with a review of performance characteristics of the Bechtel Nevada large format imaging system, a gated system capable of viewing scintillators up to 300 mm in diameter. We then examine configuration alternatives in lens coupled and fiber optically coupled electro-optical recording systems. Areas of investigation include tradeoffs between fiber optic and lens coupling, methods of image magnification, and spectral matching from scintillator to CCD camera. Key performance features discussed include field of view, resolution, sensitivity, dynamic range, and system noise characteristics

  17. Automatic Cobb Angle Determination From Radiographic Images

    NARCIS (Netherlands)

    Sardjono, Tri Arief; Wilkinson, Michael H. F.; Veldhuizen, Albert G.; van Ooijen, Peter M. A.; Purnama, Ketut E.; Verkerke, Gijsbertus J.

    2013-01-01

    Study Design. Automatic measurement of Cobb angle in patients with scoliosis. Objective. To test the accuracy of an automatic Cobb angle determination method from frontal radiographical images. Summary of Background Data. Thirty-six frontal radiographical images of patients with scoliosis. Methods.

  18. Study on image quality of radiograph in radiographic examination for circumferential welded joint. 1. Basic study on scattered radiation in double wall exposure technique

    International Nuclear Information System (INIS)

    Kato, Kiyoshi; Ooka, Norikazu.

    1997-01-01

    Wire type Image Quality Indicators (I. Q. I.) are usually used for the evaluation of the image quality of radiographs in radiographic examinations specified in the Japanese Industrial Standard (JIS). The relationship between the sensitivity of the Image Quality Indicator and the radiographic contrast in single wall exposure technique has already been well understood. However, the relationship in double wall exposure technique is still under discussion. As a result of the fundamental experiments using flat plates, it was found in this study that the image quality of radiograph depends on the ratio of scattered X-rays generated in the focus side test plate to transmitted X-rays, and that the ratio varies in inverse proportion to the distance between the flat plates. It was also shown that the simulation method based on the Compton Effect is effective in obtaining the ratio of scattered to transmitted X-rays in the double wall exposure technique for a pipe of more than 100 mm diameter. (author)

  19. Image quality preferences among radiographers and radiologists. A conjoint analysis

    International Nuclear Information System (INIS)

    Ween, Borgny; Kristoffersen, Doris Tove; Hamilton, Glenys A.; Olsen, Dag Rune

    2005-01-01

    Purpose: The aim of this study was to investigate the image quality preferences among radiographers and radiologists. The radiographers' preferences are mainly related to technical parameters, whereas radiologists assess image quality based on diagnostic value. Methods: A conjoint analysis was undertaken to survey image quality preferences; the study included 37 respondents: 19 radiographers and 18 radiologists. Digital urograms were post-processed into 8 images with different properties of image quality for 3 different patients. The respondents were asked to rank the images according to their personally perceived subjective image quality. Results: Nearly half of the radiographers and radiologists were consistent in their ranking of the image characterised as 'very best image quality'. The analysis showed, moreover, that chosen filtration level and image intensity were responsible for 72% and 28% of the preferences, respectively. The corresponding figures for each of the two professions were 76% and 24% for the radiographers, and 68% and 32% for the radiologists. In addition, there were larger variations in image preferences among the radiologists, as compared to the radiographers. Conclusions: Radiographers revealed a more consistent preference than the radiologists with respect to image quality. There is a potential for image quality improvement by developing sets of image property criteria

  20. Digital image processing of mandibular trabeculae on radiographs

    Energy Technology Data Exchange (ETDEWEB)

    Ogino, Toshi

    1987-06-01

    The present study was aimed to reveal the texture patterns of the radiographs of the mandibular trabeculae by digital image processing. The 32 cases of normal subjects and the 13 cases of patients with mandibular diseases of ameloblastoma, primordial cysts, squamous cell carcinoma and odontoma were analyzed by their intra-oral radiographs in the right premolar regions. The radiograms were digitized by the use of a drum scanner densitometry method. The input radiographic images were processed by a histogram equalization method. The result are as follows : First, the histogram equalization method enhances the image contrast of the textures. Second, the output images of the textures for normal mandible-trabeculae radiograms are of network pattern in nature. Third, the output images for the patients are characterized by the non-network pattern and replaced by the patterns of the fabric texture, intertwined plants (karakusa-pattern), scattered small masses and amorphous texture. Thus, these results indicates that the present digital image system is expected to be useful for revealing the texture patterns of the radiographs and in the future for the texture analysis of the clinical radiographs to obtain quantitative diagnostic findings.

  1. Phantom development for radiographic image optimization of chest, skull and pelvis examination for nonstandard patient

    International Nuclear Information System (INIS)

    Pina, D.R.; Duarte, S.B.; Ghilardi Netto, T.; Morceli, J.

    2009-01-01

    The construction of the adapted patient equivalent phantom (APEP) to simulate the X-ray scattering and absorption by chest, skull and pelvis of nonstandard patient in conventional radiographic equipment is presented. This APEP system is associated to the pre-existing realistic-analytic phantom (RAP) [Pina, D.R., Duarte, S.B., Ghilardi Netto, T., Trad, C. S., Brochi, M.A.C., Oliveira, S.C. de, 2004. Optimization of standard patient radiographic images for chest, skull and pelvis exams in conventional X-ray equipment. Phys. Med. Biol. 49, N215-N226] forming the coupled phantom (RAP-APEP), which is used to establish an optimization process of radiographic images of chest, skull and pelvis for nonstandard patients. A chart of the optimized radiographic technique is established covering a wide range of nonstandard patient thickness, and offering a dose reduction in comparison with those techniques currently used. Different validation processes were applied to confirm the improving of the radiographic image quality when techniques of the established chart are used

  2. Digital processing of radiographic images

    Science.gov (United States)

    Bond, A. D.; Ramapriyan, H. K.

    1973-01-01

    Some techniques are presented and the software documentation for the digital enhancement of radiographs. Both image handling and image processing operations are considered. The image handling operations dealt with are: (1) conversion of format of data from packed to unpacked and vice versa; (2) automatic extraction of image data arrays; (3) transposition and 90 deg rotations of large data arrays; (4) translation of data arrays for registration; and (5) reduction of the dimensions of data arrays by integral factors. Both the frequency and the spatial domain approaches are presented for the design and implementation of the image processing operation. It is shown that spatial domain recursive implementation of filters is much faster than nonrecursive implementations using fast fourier transforms (FFT) for the cases of interest in this work. The recursive implementation of a class of matched filters for enhancing image signal to noise ratio is described. Test patterns are used to illustrate the filtering operations. The application of the techniques to radiographic images of metallic structures is demonstrated through several examples.

  3. Study of scattering in bi-dimensional neutron radiographic images

    International Nuclear Information System (INIS)

    Oliveira, K.A.M. de; Crispim, V.R.; Silva, F.C.

    2009-01-01

    The effect of neutron scattering frequently causes distortions in neutron radiographic images and, thus, reduces the quality. In this project, a type of filter, comprised of cadmium (a neutron absorber), was used in the form of a grid to correct this effect. This device generated image data in the discrete shadow bands of the absorber, components relative to neutron scattering on the test object and surroundings. Scattering image data processing, together with the original neutron radiographic image, resulted in a corrected image with improved edge delineation and, thus, greater definition in the neutron radiographic image of the test object. The objective of this study is to propose a theoretical/experimental methodology that is capable of eliminating the components relative to neutron scattering in neutron radiographic images, coming from the material that composes the test object and the materials that compose the surrounding area. (author)

  4. Stepped scanner radiographic imaging system

    International Nuclear Information System (INIS)

    Lapidus, S.N.

    1981-01-01

    The imaging system includes a radiographic camera, a bed for supporting a subject in view of the camera, and a display system. The camera provides X and Y coordinate signals of each radiographic event. The position of the bed relative to the camera is altered sequentially by drive means, between each of a sequence of images provided by the camera. The sequentially occurring images are presented on the display system, each image being positioned on the display in correspondence with the location of the bed relative to the camera. The coordinates of each image point presented on the display is equal to the sum of the respective X and Y coordinate signals from the camera with X and Y coordinate signals provided by a timer which controls the drive means and defines the location of the bed relative to the camera. The camera is electronically decoupled from the display by a gate during movement of the bed relative to the camera from one location to the next location to prevent any smearing effect within the composite image presented on the display. (author)

  5. Methodology to evaluation of the density in radiographic image

    International Nuclear Information System (INIS)

    Louzada, M.J.Q.; Pela, C.A.; Belangero, W.D.; Santos-Pinto, R.

    1998-01-01

    This study was designed in order to optimize the optical densitometry technique in radiographic images by the setorization of the characteristic curves of the radiographic films. We used 24 radiographs of a stepped aluminium wedge that were taken without rigorous control development and manually revealed. The densitometric values of the steps images and its thickness, for each radiographic, was utilized to generate its particular mathematics expressions that represent its characteristic densitometric curves and then it were used for setorization. The densitometric values were obtained by a Macbeth TD528 densitometer. The study showed an optimization in the representation of the relationship between the optical density of the steps images of the wedge and its correspondent thickness, provided by the setorization, with mean square error around 10 -5 . This optimization will allow the use of this methodology in quantitative evaluations of bone mass, by radiographic images. (author)

  6. Adsorbed radioactivity and radiographic imaging of surfaces of stainless steel and titanium

    Science.gov (United States)

    Jung, Haijo

    1997-11-01

    Type 304 stainless steel used for typical surface materials of spent fuel shipping casks and titanium were exposed in the spent fuel storage pool of a typical PWR power plant. Adsorption characteristics, effectiveness of decontamination by water cleaning and by electrocleaning, and swipe effectiveness on the metal surfaces were studied. A variety of environmental conditions had been manipulated to stimulate the potential 'weeping' phenomenon that often occurs with spent fuel shipping casks during transit. In a previous study, few heterogeneous effects of adsorbed contamination onto metal surfaces were observed. Radiographic images of cask surfaces were made in this study and showed clearly heterogeneous activity distributions. Acquired radiographic images were digitized and further analyzed with an image analysis computer package and compared to calibrated images by using standard sources. The measurements of activity distribution by using the radiographic image method were consistent with that using a HPGe detector. This radiographic image method was used to study the effects of electrocleaning for total and specified areas. The Modulation Transfer Function (MTF) of a film-screen system in contact with a radioactive metal surface was studied with neutron activated gold foils and showed more broad resolution properties than general diagnostic x-ray film-screen systems. Microstructure between normal areas and hot spots showed significant differences, and one hot spot appearing as a dot on the film image consisted of several small hot spots (about 10 μm in diameter). These hot spots were observed as structural defects of the metal surfaces.

  7. An Applied Image Processing for Radiographic Testing

    International Nuclear Information System (INIS)

    Ratchason, Surasak; Tuammee, Sopida; Srisroal Anusara

    2005-10-01

    An applied image processing for radiographic testing (RT) is desirable because it decreases time-consuming, decreases the cost of inspection process that need the experienced workers, and improves the inspection quality. This paper presents the primary study of image processing for RT-films that is the welding-film. The proposed approach to determine the defects on weld-images. The BMP image-files are opened and developed by computer program that using Borland C ++ . The software has five main methods that are Histogram, Contrast Enhancement, Edge Detection, Image Segmentation and Image Restoration. Each the main method has the several sub method that are the selected options. The results showed that the effective software can detect defects and the varied method suit for the different radiographic images. Furthermore, improving images are better when two methods are incorporated

  8. Comparison of two interpolation methods for empirical mode decomposition based evaluation of radiographic femur bone images.

    Science.gov (United States)

    Udhayakumar, Ganesan; Sujatha, Chinnaswamy Manoharan; Ramakrishnan, Swaminathan

    2013-01-01

    Analysis of bone strength in radiographic images is an important component of estimation of bone quality in diseases such as osteoporosis. Conventional radiographic femur bone images are used to analyze its architecture using bi-dimensional empirical mode decomposition method. Surface interpolation of local maxima and minima points of an image is a crucial part of bi-dimensional empirical mode decomposition method and the choice of appropriate interpolation depends on specific structure of the problem. In this work, two interpolation methods of bi-dimensional empirical mode decomposition are analyzed to characterize the trabecular femur bone architecture of radiographic images. The trabecular bone regions of normal and osteoporotic femur bone images (N = 40) recorded under standard condition are used for this study. The compressive and tensile strength regions of the images are delineated using pre-processing procedures. The delineated images are decomposed into their corresponding intrinsic mode functions using interpolation methods such as Radial basis function multiquadratic and hierarchical b-spline techniques. Results show that bi-dimensional empirical mode decomposition analyses using both interpolations are able to represent architectural variations of femur bone radiographic images. As the strength of the bone depends on architectural variation in addition to bone mass, this study seems to be clinically useful.

  9. OFF-SITE SMARTPHONE VS. STANDARD WORKSTATION IN THE RADIOGRAPHIC DIAGNOSIS OF SMALL INTESTINAL MECHANICAL OBSTRUCTION IN DOGS AND CATS.

    Science.gov (United States)

    Noel, Peter G; Fischetti, Anthony J; Moore, George E; Le Roux, Alexandre B

    2016-09-01

    Off-site consultations by board-certified veterinary radiologists benefit residents and emergency clinicians by providing immediate feedback and potentially improving patient outcome. Smartphone devices and compressed images transmitted by email or text greatly facilitate availability of these off-site consultations. Criticism of a smartphone interface for off-site consultation is mostly directed at image degradation relative to the standard radiographic viewing room and monitors. The purpose of this retrospective, cross-sectional, methods comparison study was to compare the accuracy of abdominal radiographs in two imaging interfaces (Joint Photographic Experts Group, off-site, smartphone vs. Digital Imaging and Communications in Medicine, on-site, standard workstation) for the diagnosis of small intestinal mechanical obstruction in vomiting dogs and cats. Two board-certified radiologists graded randomized abdominal radiographs using a five-point Likert scale for the presence of mechanical obstruction in 100 dogs or cats presenting for vomiting. The area under the receiver operator characteristic curves for both imaging interfaces was high. The accuracy of the smartphone and traditional workstation was not statistically significantly different for either reviewer (P = 0.384 and P = 0.536). Correlation coefficients were 0.821 and 0.705 for each reviewer when the same radiographic study was viewed in different formats. Accuracy differences between radiologists were potentially related to years of experience. We conclude that off-site expert consultation with a smartphone provides an acceptable interface for accurate diagnosis of small intestinal mechanical obstruction in dogs and cat. © 2016 American College of Veterinary Radiology.

  10. Optimisation of the digital radiographic imaging of suspected non-accidental injury

    Science.gov (United States)

    Offiah, Amaka

    Aim: To optimise the digital (radiographic) imaging of children presenting with suspected non-accidental injury (NAI). Objectives: (i) To evaluate existing radiographic quality criteria, and to develop a more suitable system if these are found to be inapplicable to skeletal surveys obtained in suspected NAI. (ii) To document differences in image quality between conventional film-screen and the recently installed Fuji5000R computed radiography (CR) system at Great Ormond Street Hospital for Children, (iii) To document the extent of variability in the standard of skeletal surveys obtained in the UK for suspected NAI. (iv) To determine those radiographic parameters which yield the highest diagnostic accuracy, while still maintaining acceptable radiation dose to the child, (v) To determine how varying degrees of edge-enhancement affect diagnostic accuracy. (vi) To establish the accuracy of soft compared to hard copy interpretation of images in suspected NAI. Materials and Methods: (i) and (ii) Retrospective analysis of 286 paediatric lateral spine radiographs by two observers based on the Commission of European Communities (CEC) quality criteria, (iii) Review of the skeletal surveys of 50 consecutive infants referred from hospitals throughout the United Kingdom (UK) with suspected NAI. (iv) Phantom studies. Leeds TO. 10 and TO. 16 test objects were used to compare the relationship between film density, exposure parameters and visualisation of object details, (iv) Clinical study. Anteroposterior and lateral post mortem skull radiographs of six consecutive infants were obtained at various exposures. Six observers independently scored the images based on visualisation of five criteria, (v) and (vi) A study of diagnostic accuracy in which six observers independently interpreted 50 radiographs from printed copies (with varying degrees of edge-enhancement) and from a monitor. Results: The CEC criteria are useful for optimisation of imaging parameters and allow the detection

  11. Use your good judgement - Radiographers' knowledge in image production work

    International Nuclear Information System (INIS)

    Larsson, W.; Lundberg, N.; Hillergard, K.

    2009-01-01

    It has been shown that the demand for radiography services has markedly increased and radiographers' work has become more complex as their role has changed. More specifically, it entails new activities, new ways of communicating and new responsibilities. This means that radiographers work in new ways and need new ways to learn. The knowledge needed in this learning process is still unexplored. The aim of this study is to identify and present how radiographers use knowledge in image production work using PACS. This is explored by studying how radiographers use their knowledge in practice. The study adopts a qualitative approach, using participant observation of and semi-structured interviews with radiographers at five Swedish hospitals. To identify properties of knowledge, Blackler's theory of knowledge components was applied. The results of this study show that radiographers use the knowledge components in different situations in their image production work. They use embrained knowledge in planning X-ray examinations and in viewing images. Encoded knowledge is required for the use of various kinds of documentation, such as manuals and protocols. Embodied knowledge is action-oriented and involves 'gut feelings'. The study also illustrates that radiographers use their knowledge at different levels as routine actors or as reflective actors, in a more static way or with a flexible attitude, more unreflectively or more as critical reflectors, and finally more as performing automatic action or problem-solving action. This study concludes that radiographers need more reflective actors in the image production process when working with PACS. The study also illustrates that radiographers need to be flexible in their work; there is little room for static work. In work they need to analyze images, it is not enough to 'check them off'; they cannot just read documents, you need to interpret them to optimize work performance. Overall, radiographers need to have a critical and

  12. Defects quantization in industrial radiographs by image processing

    International Nuclear Information System (INIS)

    Briand, F.Y.; Brillault, B.; Philipp, S.

    1988-01-01

    This paper refers to the industrial application of image processing using Non Destructive Testing by radiography. The various problems involved by the conception of a numerical tool are described. This tool intends to help radiograph experts to quantify defects and to follow up their evolution, using numerical techniques. The sequences of processings that achieve defect segmentation and quantization are detailed. They are based on the thorough knowledge of radiographs formation techniques. The process uses various methods of image analysis, including textural analysis and morphological mathematics. The interface between the final product and users will occur in an explicit language, using the terms of radiographic expertise without showing any processing details. The problem is thoroughly described: image formation, digitization, processings fitted to flaw morphology and finally product structure in progress. 12 refs [fr

  13. Initial image interpretation of appendicular skeletal radiographs: A comparison between nurses and radiographers

    International Nuclear Information System (INIS)

    Piper, Keith J.; Paterson, Audrey

    2009-01-01

    , although differences in performance between the two groups remained, with the radiographer group achieving a better overall performance than the nurse group. As patients in MIUs and A/E receive treatment based on the initial interpretation of their imaging investigations by either nurses or radiographers, the improvement after training is encouraging but the difference in the overall performance is less so. More work is required to evaluate the performance of radiographers and nurses undertaking initial image interpretation as part of their normal practice

  14. Review and evaluation of technology, equipment, codes and standards for digitization of industrial radiographic film

    International Nuclear Information System (INIS)

    1992-05-01

    This reports contains a review and evaluation of the technology, equipment, and codes and standards related to the digitization of industrial radiographic film. The report presents recommendations and equipment-performance specifications that will allow the digitization of radiographic film from nuclear power plant components in order to produce faithful reproductions of flaw images of interest on the films. Justification for the specifications selected are provided. Performance demonstration tests for the digitization process are required and criteria for such tests is presented. Also several comments related to implementation of the technology are presented and discussed

  15. Black Lung Benefits Act: standards for chest radiographs. Direct final rule; request for comments.

    Science.gov (United States)

    2013-06-13

    Physicians and adjudicators use chest radiographs (X-rays) as a tool in evaluating whether a coal miner suffers from pneumoconiosis (black lung disease). Accordingly, the Department's regulations implementing the Black Lung Benefits Act allow the submission of radiographs in connection with benefit claims and set out quality standards for their performance. These standards are currently limited to film radiographs. In recent years, many medical facilities have phased out film radiography in favor of digital radiography. This direct final rule updates the existing film-radiograph standards and provides parallel standards for digital radiographs. This rule also updates outdated terminology and removes certain obsolete provisions.

  16. 78 FR 53645 - Black Lung Benefits Act: Standards for Chest Radiographs

    Science.gov (United States)

    2013-08-30

    ...-AA07 Black Lung Benefits Act: Standards for Chest Radiographs AGENCY: Office of Workers' Compensation... connection with claims filed under the Black Lung Benefits Act. The comment period closed on August 12, 2013..., 2013, OWCP published the direct final rule, Black Lung Benefits Act: Standards for Chest Radiographs...

  17. Knee Images Digital Analysis (KIDA): a novel method to quantify individual radiographic features of knee osteoarthritis in detail.

    Science.gov (United States)

    Marijnissen, A C A; Vincken, K L; Vos, P A J M; Saris, D B F; Viergever, M A; Bijlsma, J W J; Bartels, L W; Lafeber, F P J G

    2008-02-01

    Radiography is still the golden standard for imaging features of osteoarthritis (OA), such as joint space narrowing, subchondral sclerosis, and osteophyte formation. Objective assessment, however, remains difficult. The goal of the present study was to evaluate a novel digital method to analyse standard knee radiographs. Standardized radiographs of 20 healthy and 55 OA knees were taken in general practise according to the semi-flexed method by Buckland-Wright. Joint Space Width (JSW), osteophyte area, subchondral bone density, joint angle, and tibial eminence height were measured as continuous variables using newly developed Knee Images Digital Analysis (KIDA) software on a standard PC. Two observers evaluated the radiographs twice, each on two different occasions. The observers were blinded to the source of the radiographs and to their previous measurements. Statistical analysis to compare measurements within and between observers was performed according to Bland and Altman. Correlations between KIDA data and Kellgren & Lawrence (K&L) grade were calculated and data of healthy knees were compared to those of OA knees. Intra- and inter-observer variations for measurement of JSW, subchondral bone density, osteophytes, tibial eminence, and joint angle were small. Significant correlations were found between KIDA parameters and K&L grade. Furthermore, significant differences were found between healthy and OA knees. In addition to JSW measurement, objective evaluation of osteophyte formation and subchondral bone density is possible on standard radiographs. The measured differences between OA and healthy individuals suggest that KIDA allows detection of changes in time, although sensitivity to change has to be demonstrated in long-term follow-up studies.

  18. A computer aided measurement method for unstable pelvic fractures based on standardized radiographs

    International Nuclear Information System (INIS)

    Zhao, Jing-xin; Zhao, Zhe; Zhang, Li-cheng; Su, Xiu-yun; Du, Hai-long; Zhang, Li-ning; Zhang, Li-hai; Tang, Pei-fu

    2015-01-01

    To set up a method for measuring radiographic displacement of unstable pelvic ring fractures based on standardized X-ray images and then test its reliability and validity using a software-based measurement technique. Twenty-five patients that were diagnosed as AO/OTA type B or C pelvic fractures with unilateral pelvis fractured and dislocated were eligible for inclusion by a review of medical records in our clinical centre. Based on the input pelvic preoperative CT data, the standardized X-ray images, including inlet, outlet, and anterior-posterior (AP) radiographs, were simulated using Armira software (Visage Imaging GmbH, Berlin, Germany). After representative anatomic landmarks were marked on the standardized X-ray images, the 2-dimensional (2D) coordinates of these points could be revealed in Digimizer software (Model: Mitutoyo Corp., Tokyo, Japan). Subsequently, we developed a formula that indicated the translational and rotational displacement patterns of the injured hemipelvis. Five separate observers calculated the displacement outcomes using the established formula and determined the rotational patterns using a 3D-CT model based on their overall impression. We performed 3D reconstruction of all the fractured pelvises using Mimics (Materialise, Haasrode, Belgium) and determined the translational and rotational displacement using 3-matic suite. The interobserver reliability of the new method was assessed by comparing the continuous measure and categorical outcomes using intraclass correlation coefficient (ICC) and kappa statistic, respectively. The interobserver reliability of the new method for translational and rotational measurement was high, with both ICCs above 0.9. Rotational outcome assessed by the new method was the same as that concluded by 3-matic software. The agreement for rotational outcome among orthopaedic surgeons based on overall impression was poor (kappa statistic, 0.250 to 0.426). Compared with the 3D reconstruction outcome, the

  19. Radiographic analysis of the temporomandibular joint by the standardized projection technique

    International Nuclear Information System (INIS)

    Choe, Han Up; Park, Tae Won

    1983-01-01

    The purpose of this study was to investigate the radiographic images of the condylar head in clinically normal subjects and the TMJ patients using standardized projection technique. 45 subjects who have not clinical evidence of TMJ problems and 96 patients who have the clinical evidence of TMJ problems were evaluated, but the patients who had fracture, trauma and tumor on TMJ area were discluded in this study. For the evaluation of radiographic images, the author has observed the condylar head positions in closed mouth and 2.54 cm open mouth position taken by the standardized transcranial oblique lateral projection technique. The results were as follow: 1. In closed mouth position, the crest of condylar head took relatively posterior position to the deepest point of the glenoid fossa in 8.9% of the normals and in 26.6% of TMJ patients. 2. In 2.54 cm open mouth position, condylar head took relatively posterior position to the articular eminence in 2 .2% of TMJ patients and 39.6% of the normals. 3. In open mouth position, the horizontal distance from the deepest point of the glenoid fossa to the condylar head was 13.96 mm in the normals and 10.68 mm in TMJ patients. 4. The distance of true movement of condylar head was 13.49 mm in the normals and 10.27 mm in TMJ patients. 5. The deviation of mandible in TMJ patients was slightly greater than of the normals.

  20. A novel tool for automated evaluation of radiographic weld images

    International Nuclear Information System (INIS)

    Rajagopalan, C.; Venkatraman, B.; Jayakumar, T.; Kalyanasundaram, P.; Raj, B.

    2004-01-01

    Radiography is one of the oldest and the most widely used NDT method for the detection of volumetric defects in welds and castings. Once a radiograph of a weld or a casting or an assembly is taken, the radiographer examines the same. The task of the radiographer consists of identifying the defects and quantitatively evaluating the same based on codes and specifications. Radiographic interpretation primarily depends on the expertise of the individual radiographer. To overcome the subjectivity involved in human interpretation, it is thus desirable to develop a computer based automated system to aid in the interpretation of radiographs. Towards this goal, the authors have developed a flowchart chalking out the various stages involved. Typical weld images of tube to tubesheet weld joints were digitised using high resolution digitiser. The images were segmented and 52 invariant moments were computed to be used as features. The results of these are presented in this paper. Once the features (invariant moments) are extracted and ranked, a neural network classifier based on error back-propagation has to classify the (top ranking) features and evaluate the image for acceptance or rejection. (author)

  1. Conversion into numerical form of radiographic images

    International Nuclear Information System (INIS)

    Cappabianca, C.; Della Rocca, A.B.; Ferriani, S.

    1986-01-01

    Radiographic means are widely used for non destructive testing. However, human and technological factors strongly influence reliability of the results and further use of these technique. Image Processing can help to overtake those difficulties if radiographic films are previously digitized. This paper shows methods and equipments used in this field. The system EDI (Enea Digital. Imagery) operating in Casaccia Energy Research Centre is described

  2. Magnetic resonance imaging and radiographic findings of seal finger

    International Nuclear Information System (INIS)

    Marjelund, S.; Tikkakoski, T.; Isokangas, M.; Raeisaenen, S.

    2006-01-01

    Purpose: To describe the magnetic resonance imaging (MRI) and radiographic findings of five patients with seal finger. Material and Methods: The MR images and radiographs of five patients with seal finger were retrospectively evaluated. MRI was performed on four patients in the subacute phase, and follow-up imaging was done on one of them at 5 months. One patient had MRI only at a later stage 5 years after onset. Radiographs were taken three times in the subacute phase and once at a later stage. One patient had had seal finger in another finger previously. Results: Short-tau inversion-recovery (STIR) sequence showed extensive subcutaneous soft tissue edema in all four patients in the subacute phase and tenosynovitis of the flexion tendons in two cases. Three patients had edema in 2-3 phalanges, and effusion in the distal interphalangeal (DIP) joint was seen in one case. At the later stage, no signal pathology in soft tissues or bones was seen in STIR images. In the subacute phase, radiographs showed digital soft-tissue swelling in three patients, and one patient had a narrowed DIP joint, periarticular osteoporosis, and a periosteal reaction. At the later stage, flexion contracture of the finger was seen. Conclusion: In addition to soft-tissue infection, seal finger causes bone marrow edema, tenosynovitis, and effusion in the interphalangeal joints visible as increased signal intensity in STIR images. Radiographs reveal periarticular osteoporosis with loss of cartilage in the subacute phase and flexion contracture at the later stage. MRI (STIR) allows more precise delineation of the inflammatory process compared to radiography

  3. Magnetic resonance imaging and radiographic findings of seal finger

    Energy Technology Data Exchange (ETDEWEB)

    Marjelund, S.; Tikkakoski, T.; Isokangas, M.; Raeisaenen, S. [Oulu Univ. Hospital (Finland). Dept. of Radiology

    2006-12-15

    Purpose: To describe the magnetic resonance imaging (MRI) and radiographic findings of five patients with seal finger. Material and Methods: The MR images and radiographs of five patients with seal finger were retrospectively evaluated. MRI was performed on four patients in the subacute phase, and follow-up imaging was done on one of them at 5 months. One patient had MRI only at a later stage 5 years after onset. Radiographs were taken three times in the subacute phase and once at a later stage. One patient had had seal finger in another finger previously. Results: Short-tau inversion-recovery (STIR) sequence showed extensive subcutaneous soft tissue edema in all four patients in the subacute phase and tenosynovitis of the flexion tendons in two cases. Three patients had edema in 2-3 phalanges, and effusion in the distal interphalangeal (DIP) joint was seen in one case. At the later stage, no signal pathology in soft tissues or bones was seen in STIR images. In the subacute phase, radiographs showed digital soft-tissue swelling in three patients, and one patient had a narrowed DIP joint, periarticular osteoporosis, and a periosteal reaction. At the later stage, flexion contracture of the finger was seen. Conclusion: In addition to soft-tissue infection, seal finger causes bone marrow edema, tenosynovitis, and effusion in the interphalangeal joints visible as increased signal intensity in STIR images. Radiographs reveal periarticular osteoporosis with loss of cartilage in the subacute phase and flexion contracture at the later stage. MRI (STIR) allows more precise delineation of the inflammatory process compared to radiography.

  4. An exploratory study of radiographer's perceptions of radiographer commenting on musculo-skeletal trauma images in rural community based hospitals

    International Nuclear Information System (INIS)

    Howard, Morag L.

    2013-01-01

    Aim: This study sought to explore the perceptions of community hospital based radiographers in North East Scotland regarding the practice of radiographer commenting on musculo-skeletal trauma images. Method: A purposive sample of radiographers (n = 8) were recruited from community hospitals throughout the North-east of Scotland. A qualitative, exploratory study was conducted employing semi-structured interviews consisting of one focus group and two individual interviews. The interviews were audio recorded and transcribed in full to allow thematic analysis of the data using a framework adapted from Pope and Mays (2006). Main findings: This study revealed that the practice of radiographer commenting in the community provides a valuable front line opinion on musculo-skeletal trauma image appearances to enhance diagnostic outcomes for patients and streamline their care pathway. The appreciation shown from inter-professional colleagues for this practice induced feelings of professional pride and job satisfaction in the sample group. All participants expressed a desire to undertake additional training to allow progression from radiographer commenting to radiographer reporting of musculo-skeletal trauma images. Perceived barriers to the practice of radiographer commenting were time constraints and a lack of support with regards to continuing professional development (CPD) opportunities and mentorship from radiology colleagues. Conclusion: The practice of radiographer commenting in the community setting should be supported by ongoing training, and radiologist involvement in mentoring could provide radiographers with a valuable support mechanism. The voice of all radiographers regarding this extended role must be heard by professional leaders to ensure that the skills and education required for radiographer commenting are provided and subsequent patient care is not compromised

  5. Radiographic imaging for Ilizarov limb lengthening in children

    International Nuclear Information System (INIS)

    Blane, C.E.; DiPietro, M.A.; Herzenberg, J.E.

    1991-01-01

    The Ilizarov method for limb lengthening is rapidly gaining popularity in North America. Use of this new technique has necessitated modifications in radiographic protocol. Initial imaging problems gained from our experience with twenty children are detailed including accurate centering for the plain films, correcting for magnification to accurately measure the distraction gap and the expected radiographic appearance of the regenerate bone. Ultrasonography has potential value in accurately measuring the distraction gap and in imaging the new bone prior to radiographic appearance. Since overly fast distraction inhibits bone formation and overly slow distraction leads to premature consolidation, ultrasound may serve a useful role in the qualitative evaluation of new bone formation in Ilizarov limb lengthening, enabling the orthopedic surgeon to tailor the distraction rate to the particular child. (orig.)

  6. Algorithms for boundary detection in radiographic images

    International Nuclear Information System (INIS)

    Gonzaga, Adilson; Franca, Celso Aparecido de

    1996-01-01

    Edge detecting techniques applied to radiographic digital images are discussed. Some algorithms have been implemented and the results are displayed to enhance boundary or hide details. An algorithm applied in a pre processed image with contrast enhanced is proposed and the results are discussed

  7. Image quality in digital radiographic systems

    Directory of Open Access Journals (Sweden)

    Almeida Solange Maria de

    2003-01-01

    Full Text Available The aim of the present study was to evaluate the image quality of four direct digital radiographic systems. Radiographs were made of the maxillary central incisor and mandibular left molar regions of a dry skull, and an aluminum step-wedge. The X-ray generator operated at 10 mA, 60 and 70 kVp, and images were acquired with 3, 5, 8, 12, 24 and 48 exposure pulses. Six well-trained observers classified the images by means of scores from 1 to 3. Collected data were submitted to nonparametric statistical analysis using Fisher's exact test. Statistical analysis showed significant differences (p<0.01 in image quality with the four systems. Based on the results, it was possible to conclude that: 1 all of the digital systems presented good performance in producing acceptable images for diagnosis, if the exposures of the step-wedge and the maxillary central incisor region were made at 5 pulses, as well as at 8 pulses for the mandibular left molar region, selecting 60 or 70kVp; 2 higher percentages of acceptable images were obtained with the administration of lower radiation doses in CCD-sensors (charge-coupled device; 3 the Storage Phosphor systems produced acceptable images at a large range of exposure settings, that included low, intermediate and high radiation doses.

  8. Imaging of juvenile spondyloarthritis. Part I: Classifications and radiographs

    Directory of Open Access Journals (Sweden)

    Iwona Sudoł-Szopińska

    2017-09-01

    Full Text Available Juvenile spondyloarthropathies are manifested mainly by symptoms of peripheral arthritis and enthesitis. By contrast with adults, children rarely present with sacroiliitis and spondylitis. Imaging and laboratory tests allow early diagnosis and treatment. Conventional radiographs visualize late inflammatory lesions and post-inflammatory complications. Early diagnosis is possible with the use of ultrasonography and magnetic resonance imaging. The first part of the article presents classifications of juvenile spondyloarthropathies and discusses their radiographic presentation. Typical radiographic features of individual types of juvenile spondyloarthritis are listed (including ankylosing spondylitis, juvenile psoriatic arthritis, reactive arthritis and arthritis in the course of inflammatory bowel diseases. The second part will describe changes visible on ultrasonography and magnetic resonance imaging. In patients with juvenile spondyloarthropathies, these examinations are conducted to diagnose inflammatory lesions in peripheral joints, tendon sheaths, tendons and bursae. Moreover, magnetic resonance imaging also visualizes early inflammatory changes in the axial skeleton and subchondral bone marrow edema, which is considered an early sign of inflammation.

  9. Stepped scanner radiographic imaging system using edge blending

    International Nuclear Information System (INIS)

    Lapidus, S.N.

    1984-01-01

    An imaging system is described which includes a radiographic camera, a bed for supporting a subject in view of the camera, and a display system. The camera provides X and Y coordinate signals for each radiographic event. The position of the bed relative to the camera is altered stepwise and a sequence of images is provided by the camera each image being positioned on a display system in correspondence with the location of the bed relative to the camera. The camera is electronically decoupled from the display by a gate during movement of the bed relative to the camera from one location to the next location to prevent any smearing effect within the composite image presented on the display. The edges of contiguous images making up the composite image are blended by electronically adjusting their boundary regions so as to provide overlapping or interlocking. (author)

  10. Theoretical analysis of radiographic images by nonstationary Poisson processes

    International Nuclear Information System (INIS)

    Tanaka, Kazuo; Uchida, Suguru; Yamada, Isao.

    1980-01-01

    This paper deals with the noise analysis of radiographic images obtained in the usual fluorescent screen-film system. The theory of nonstationary Poisson processes is applied to the analysis of the radiographic images containing the object information. The ensemble averages, the autocorrelation functions, and the Wiener spectrum densities of the light-energy distribution at the fluorescent screen and of the film optical-density distribution are obtained. The detection characteristics of the system are evaluated theoretically. Numerical examples one-dimensional image are shown and the results are compared with those obtained under the assumption that the object image is related to the background noise by the additive process. (author)

  11. The impact of image test bank construction on radiographic interpretation outcomes: A comparison study

    International Nuclear Information System (INIS)

    Hardy, M.; Flintham, K.; Snaith, B.; Lewis, E.F.

    2016-01-01

    Introduction: Assessment of image interpretation competency is commonly undertaken through review of a defined image test bank. Content of these image banks has been criticised for the high percentage of abnormal examinations which contrasts with lower reported incidences of abnormal radiographs in clinical practice. As a result, questions have been raised regarding the influence of prevalence bias on the accuracy of interpretive decision making. This article describes a new and novel approach to the design of musculoskeletal image test banks. Methods: Three manufactured image banks were compiled following a standard academic menu in keeping with previous studies. Three further image test banks were constructed to reflect local clinical workload within a single NHS Trust. Eighteen radiographers, blinded to the method of test bank composition, were randomly assigned 2 test banks to review (1 manufactured, 1 clinical workload). Comparison of interpretive accuracy was undertaken. Results: Inter-rater agreement was moderate to good for all image banks (manufactured: range k = 0.45–0.68; clinical workload: k = 0.49–0.62). A significant difference in mean radiographer sensitivity was noted between test bank designs (manufactured 87.1%; clinical workload 78.5%; p = 0.040, 95% CI = 0.4–16.8; t = 2.223). Relative parity in radiographer specificity and overall accuracy was observed. Conclusion: This study confirms the findings of previous research that high abnormality prevalence image banks over-estimate the ability of observers to identify abnormalities. Assessment of interpretive competency using an image bank that reflects local clinical practice is a better approach to accurately establish interpretive competency and the learning development needs of individual practitioners. - Highlights: • High prevalence image test banks over-estimate the ability of observers. • Clinical workload test banks may better reflect image interpretation competency.

  12. Study on the abnormal image appeared in radiographs of welds, 3

    International Nuclear Information System (INIS)

    Hayashi, Morihiro; Sugimura, Seiichi; Umemura, Kunio; Imamura, Senji; Kanno, Munekazu.

    1984-01-01

    On the abnormal images arising at times in the X-ray radiographs of austenitic stainless steel welded parts, the cause of occurrence was clarified before. In this study, the authors made the welded parts of austenitic stainless steel SUS 304 and SUS 316 with abnormal images of different clearness by making heat input into respective layers of welds large or small, and compared the static and dynamic strength. Moreover, the relation of the form of abnormal images in radiographs to metal structures was studied. The welding method employed was TIG welding and submerged arc welding. The images of X-ray radiographs and the metal structures of the welded parts tested are shown. The mechanical strength test was carried out by tension, bending and impact. Also fatigue test was performed. In the welded parts of SUS 304 and SUS 316, even if abnormal images appeared in radiographs, when sound welding was made, they possessed sufficient strength statically and dynamically. In the macroscopic and microscopic cross-sectional structures of the welded parts with remarkable abnormal images, defect was not observed at all. The cause of abnormal image appearance is the diffraction of X-ray. (Kako, I.)

  13. Standardization principles of radiographic investigation of concrete structures

    International Nuclear Information System (INIS)

    Runkiewicz, L.

    1979-01-01

    The PN-78/B-06264 Polish Standard concerning the radiographic methods of concrete structure control is discussed. It concerns the inner structure of the building elements, dimensions and position of honeycombs and reinforcement. (author)

  14. Single exposure simultaneous acquisition of digital and conventional radiographs utilizing unaltered dose

    International Nuclear Information System (INIS)

    Oestmann, J.W.; Greene, R.

    1988-01-01

    We describe the simultaneous acquisition of digital and conventional radiographs with a single standard radiographic exposure. A digitizable storage phosphor (ST Imaging Plate, Fuji) is sandwiched into a radiographic cassette (X-Omatic, Kodak) behind a conventional radiographic film-screen combination (Lanex medium screens, OC film, Kodak). The barium fluorohalide storage phosphor is digitized with a helium-neon laser scanner (TCR 201, Toshiba), and the conventional radiograph is processed in the standard fashion (M7B, Kodak). The storage phosphor is exposed by the 'wasted' radiation normally exiting the back of the film-screen combination (32% of the cassette entrance dose at 141 kVp). At a standard exposure (6.3 mAs), the conventional radiograph is of unaltered quality, and the digital image appears to have an adequate signal-to-noise ratio for chest studies despite the lower exposure dose. This technique produces twin images of identical spatial and temporal registration and avoids the added radiation exposure normally required to carry out comparative studies. (orig.)

  15. A high-accuracy image registration algorithm using phase-only correlation for dental radiographs

    International Nuclear Information System (INIS)

    Ito, Koichi; Nikaido, Akira; Aoki, Takafumi; Kosuge, Eiko; Kawamata, Ryota; Kashima, Isamu

    2008-01-01

    Dental radiographs have been used for the accurate assessment and treatment of dental diseases. The nonlinear deformation between two dental radiographs may be observed, even if they are taken from the same oral regions of the subject. For an accurate diagnosis, the complete geometric registration between radiographs is required. This paper presents an efficient dental radiograph registration algorithm using Phase-Only Correlation (POC) function. The use of phase components in 2D (two-dimensional) discrete Fourier transforms of dental radiograph images makes possible to achieve highly robust image registration and recognition. Experimental evaluation using a dental radiograph database indicates that the proposed algorithm exhibits efficient recognition performance even for distorted radiographs. (author)

  16. Comparison of codes and standards for radiographic inspection

    International Nuclear Information System (INIS)

    Bingoeldag, M. M.; Aksu, M.; Akguen, A. F.

    1995-01-01

    This report compares the procedurel requirements and acceptance criteria for radiographic inspections specified in the relevant national and international codes and standards. In particular, detailed analysis of inspection conditions such as exposure arrangements, and contrast requirements are given

  17. Conventional versus virtual radiographs of the injured pelvis and acetabulum

    Energy Technology Data Exchange (ETDEWEB)

    Bishop, Julius A.; Rao, Allison J.; Pouliot, Michael A.; Bellino, Michael [Stanford University School of Medicine, Department of Orthopaedic Surgery, Stanford, CA (United States); Beaulieu, Christopher [Stanford University School of Medicine, Department of Radiology, Stanford, CA (United States)

    2015-09-15

    Evaluation of the fractured pelvis or acetabulum requires both standard radiographic evaluation as well as computed tomography (CT) imaging. The standard anterior-posterior (AP), Judet, and inlet and outlet views can now be simulated using data acquired during CT, decreasing patient discomfort, radiation exposure, and cost to the healthcare system. The purpose of this study is to compare the image quality of conventional radiographic views of the traumatized pelvis to virtual radiographs created from pelvic CT scans. Five patients with acetabular fractures and ten patients with pelvic ring injuries were identified using the orthopedic trauma database at our institution. These fractures were evaluated with both conventional radiographs as well as virtual radiographs generated from a CT scan. A web-based survey was created to query overall image quality and visibility of relevant anatomic structures. This survey was then administered to members of the Orthopaedic Trauma Association (OTA). Ninety-seven surgeons completed the acetabular fracture survey and 87 completed the pelvic fracture survey. Overall image quality was judged to be statistically superior for the virtual as compared to conventional images for acetabular fractures (3.15 vs. 2.98, p = 0.02), as well as pelvic ring injuries (2.21 vs. 1.45, p = 0.0001). Visibility ratings for each anatomic landmark were statistically superior with virtual images as well. Virtual radiographs of pelvic and acetabular fractures offer superior image quality, improved comfort, decreased radiation exposure, and a more cost-effective alternative to conventional radiographs. (orig.)

  18. Application of digital techniques to the restoration of radiographic images

    International Nuclear Information System (INIS)

    Burch, S.F.

    1980-09-01

    The methods of constrained least squares and maximum entropy have been used to restore digital X and γ-ray radiographs. Both methods require the blurring of the image to be a linear, spatially invariant process. Although the blurring processes in radiography can be complex, situations have been identified where these simplifying assumptions are valid. Algorithms for deriving the point-spread function of each image are discussed. These include a pinhole method for X-ray radiographs, and reconstruction from edge profiles for γ-ray radiographs. The results from the restoration of geometrically blurred radiographs of sparking plugs are given. Maximum entropy gives results superior to those obtained by constrained least squares. The resolution is improved by a factor of about three when maximum entropy is used, and by a factor of about two for constrained least squares. (author)

  19. An Algorithm for Data Hiding in Radiographic Images and ePHI/R Application

    Directory of Open Access Journals (Sweden)

    Aqsa Rashid

    2018-01-01

    Full Text Available Telemedicine is the use of Information and Communication Technology (ICT for clinical health care from a distance. The exchange of radiographic images and electronic patient health information/records (ePHI/R for diagnostic purposes has the risk of confidentiality, ownership identity, and authenticity. In this paper, a data hiding technique for ePHI/R is proposed. The color information in the cover image is used for key generation, and stego-images are produced with ideal case. As a result, the whole stego-system is perfectly secure. This method includes the features of watermarking and steganography techniques. The method is applied to radiographic images. For the radiographic images, this method resembles watermarking, which is an ePHI/R data system. Experiments show promising results for the application of this method to radiographic images in ePHI/R for both transmission and storage purpose.

  20. Image enhancement of digital periapical radiographs according to diagnostic tasks

    International Nuclear Information System (INIS)

    Choi, Jin Woo; Han, Won Jeong; Kim, Eun Kyung

    2014-01-01

    his study was performed to investigate the effect of image enhancement of periapical radiographs according to the diagnostic task. Eighty digital intraoral radiographs were obtained from patients and classified into four groups according to the diagnostic tasks of dental caries, periodontal diseases, periapical lesions, and endodontic files. All images were enhanced differently by using five processing techniques. Three radiologists blindly compared the subjective image quality of the original images and the processed images using a 5-point scale. There were significant differences between the image quality of the processed images and that of the original images (P<0.01) in all the diagnostic task groups. Processing techniques showed significantly different efficacy according to the diagnostic task (P<0.01). Image enhancement affects the image quality differently depending on the diagnostic task. And the use of optimal parameters is important for each diagnostic task.

  1. Image enhancement of digital periapical radiographs according to diagnostic tasks

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jin Woo; Han, Won Jeong; Kim, Eun Kyung [Dept. of Oral and Maxillofacial Radiology, Dankook University College of Dentistry, Cheonan (Korea, Republic of)

    2014-03-15

    his study was performed to investigate the effect of image enhancement of periapical radiographs according to the diagnostic task. Eighty digital intraoral radiographs were obtained from patients and classified into four groups according to the diagnostic tasks of dental caries, periodontal diseases, periapical lesions, and endodontic files. All images were enhanced differently by using five processing techniques. Three radiologists blindly compared the subjective image quality of the original images and the processed images using a 5-point scale. There were significant differences between the image quality of the processed images and that of the original images (P<0.01) in all the diagnostic task groups. Processing techniques showed significantly different efficacy according to the diagnostic task (P<0.01). Image enhancement affects the image quality differently depending on the diagnostic task. And the use of optimal parameters is important for each diagnostic task.

  2. Quantitative analysis of real-time radiographic systems

    International Nuclear Information System (INIS)

    Barker, M.D.; Condon, P.E.; Barry, R.C.; Betz, R.A.; Klynn, L.M.

    1988-01-01

    A method was developed which yields quantitative information on the spatial resolution, contrast sensitivity, image noise, and focal spot size from real time radiographic images. The method uses simple image quality indicators and computer programs which make it possible to readily obtain quantitative performance measurements of single or multiple radiographic systems. It was used for x-ray and optical images to determine which component of the system was not operating up to standard. Focal spot size was monitored by imaging a bar pattern. This paper constitutes the second progress report on the development of the camera and radiation image quality indicators

  3. Chesneys' radiographic imaging: revised and edited by John Ball and Tony Price. 5. ed.

    International Nuclear Information System (INIS)

    Chesney, D.N.

    1989-01-01

    This book (5th edition) reflects the change in emphasis in radiology from photographic processes towards electronic imaging methods. There is new material on image intensifiers and television imaging, digital imaging and digital subtractions. Analyses of the characteristics of, and defects in, images on radiographs, xeroradiographs and the television on screen are included. Methods, equipment and materials used to record the cathode ray tube image are described and there is new material on the principles of alternative diagnostic imaging techniques such as ultrasound, computed tomography and radionuclide imaging which provide cathode ray tube images. The book is primarily for student radiographers and radiographers studying for postdiplomate qualifications. (author)

  4. Standard digital reference images for investment steel castings for aerospace applications

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 The digital reference images provided in the adjunct to this standard illustrate various types and degrees of discontinuities occurring in thin-wall steel investment castings. Use of this standard for the specification or grading of castings requires procurement of the adjunct digital reference images which illustrate the discontinuity types and severity levels. They are intended to provide the following: 1.1.1 A guide enabling recognition of thin-wall steel casting discontinuities and their differentiation both as to type and degree through digital radiographic examination. 1.1.2 Example digital radiographic illustrations of discontinuities and a nomenclature for reference in acceptance standards, specifications and drawings. 1.2 Two illustration categories are covered as follows: 1.2.1 Graded—Six common discontinuity types each illustrated in eight degrees of progressively increasing severity. 1.2.2 Ungraded—Twelve single illustrations of additional discontinuity types and of patterns and imper...

  5. Computer simulation of radiographic images sharpness in several system of image record

    International Nuclear Information System (INIS)

    Silva, Marcia Aparecida; Schiable, Homero; Frere, Annie France; Marques, Paulo M.A.; Oliveira, Henrique J.Q. de; Alves, Fatima F.R.; Medeiros, Regina B.

    1996-01-01

    A method to predict the influence of the record system on radiographic images sharpness by computer simulation is studied. The method intend to previously show the image to be obtained for each type of film or screen-film combination used during the exposure

  6. CT imaging vs. traditional radiographic imaging for evaluating Harris Lines in tibiae

    DEFF Research Database (Denmark)

    Primeau, Charlotte; Jakobsen, Lykke Schrøder; Lynnerup, Niels

    2016-01-01

    This paper is the first to systematically investigate computer tomography (CT) images vs. ordinary flat plane radiography for evaluating Harris Lines (HL) on tibiae. Harris Lines are traditionally investigated using radiographic images and recorded as either present or absent, or by counting...

  7. Adaptation of a homogeneous phantom, equivalent to the adult patient, for evaluation of pediatric radiographic images

    International Nuclear Information System (INIS)

    Oliveira, Silvana Carvalho de

    1996-01-01

    Based upon the ALARA principle (As Low As Reasonably Achievable), the pediatric diagnostic radiology deserves special attention by the importance in maintaining the doses at the lowest possible levels, due to the higher life expectancy of these age groups, that increases the probabilities of occurring the deleterious effects due to radiation exposures. An effective quality control program produces a large potential of dose reduction in diagnostic radiology, by the establishment of radiographic techniques to the production of abetter radiographic image, with less radiation doses to the patient. The principal aim of the present work, was the adaptation of an homogeneous phantom equivalent to a standard adult patient, to the determination and optimization of radiographic techniques in pediatric examinations. The phantom enables the simulation of the chest, skull or pelvis and the extremities. After the obtention of several techniques for each examination evaluated, the utilization of a phantom with common structures in radiology, enabled the standardization of the technique to provide a better contrast between different structures, for each examination. At another stage of this work, the sensitometric characteristics of a rare-earth screen-film system were evaluated and compared to those of a conventional calcium tungstate system. The results indicated that the rare-earth systems offer significant dose reduction and images of good quality. (author)

  8. A study on secondary images in panoramic radiograph

    International Nuclear Information System (INIS)

    Cho, Dai Hee; Kim, Han Pyong

    1984-01-01

    This study was performed to observe the secondary images and to analyse the relationships between the primary and secondary images in panoramic radiograph. Using the Morita's Panex-EC panoramic x-ray machine and the human dry skull, the author analysed 17 radiographs which were selected from 65 radiographs of the dry skull that attached the radiopaque materials, and the attached regions of the radiopaque materials were the normal anatomical structures which were important and selected as a region for the evaluation of the secondary images effectively. The results were as follows; 1. The cervical vertebrae showed three images. The midline image was the most distorted and less clear, and bilateral images were slightly superimposed over the posterior border of the mandibular ramus. 2. In mandible, the secondary image of the posterior border of the ramus was superimposed on the opposite ramus region, and this image was elongated from the anterior border of the ramus to the lateral side of the posterior border of the ramus. The secondary image of the condyle was observed on the upper area of the coronoid process, the sigmoid notch and the condyle in opposite side. 3. In maxilla, the posterior region of the hard palate showed the secondary image on the lower part of the nasal cavity and the medial wall of the maxillary sinus. 4. The primary images of the occipital condyle and the mastoid process appeared on the same region, and only the secondary image of the occipital condyle was observed symmetrically on the opposite side with similar shape to the primary one. 5. In the cranial base, the anatomical structures of the midsagittal portions like a inferior border of the frontal sinus, sella turcica, inferior border of the sphenoid sinus and inferior border of the posterior part of the occipital bone showed the similar shape between the primary and secondary images symmetrically. 6. The petrous portion of the temporal bone showed the secondary image of the lateral side of

  9. Diagnostic ability of the periapical radiographs and digital image in the detection of the artificial proximal caries

    International Nuclear Information System (INIS)

    Heo, Min Suk; You, Dong Soo

    1994-01-01

    Recently, the digital image was introduced into radiological image. The digital image has the power of contrast enhancement, histogram control, and other digitally enhancement. At the point of the resolution, periapical radiograph is superior to the digital image, but enhanced digital procedure improves the diagnostic ability of the digital image. The purpose of this study was to evaluate the diagnostic ability of artificial proximal caries in conventional radiographs, digital radiographs and enhanced digital radiographs (histogram specification). ROC (Receiver Operating Characteristic) analysis and paired t-test were used for the evaluation of detectability, and following results were acquired: 1. The mean ROC area of conventional radiographs was 0.9274. 2. The mean ROC area of unenhanced digital image was 0.9168. 3. The mean ROC area of enhanced digital image was 0.9339. 4. The diagnostic ability of three imaging methods was not significant difference (p>0.05). So, the digital images had similar diagnostic ability of artificial proximal caries to conventional radiographs. If properly enhanced digital image, it may be superior to conventional radiographs.

  10. Data acquisition system for radiographic imaging

    International Nuclear Information System (INIS)

    Lanza, R.C.; Votano, J.R.; Russ, T.

    1992-01-01

    This patent describes a continuous data acquisition system for radiographic imaging without interrupting acquisition activity the acquisition system. It comprises at least two memory means for storing radiographic data from a radiation detector wherein each of the memory means having a plurality of addressable memory locations and each of the memory means are such that the locations of the memory means correspond to spatial locations in the radiation detector; logic control means for sensing radiographic data transmitted by the radiation detector, for selecting one of the memory means for storage of the data, for transferring data to the selected memory means, and for switching form one memory means to another memory means according to a predefined schedule and according to memory capacity level, the logic control means further comprising a logic device which receives data and increments the contents of locations in a memory means in response to such data; and interface control means for reading data from one or the other memory means when such memory means is not actively acquiring data such that data can be acquired continuously by the system

  11. Physiological conditions for the effective interpretation of radiographic images

    International Nuclear Information System (INIS)

    Overington, I.

    1989-01-01

    A wide range of factors influence the ability of the human observer to perceive detail in images. Most of these factors are of some significance in interpretation of one or more types of radiographic image. Human observer performance may be conveniently categorized in terms of multiparametric threshold surfaces, suprathreshold visibility and observer variance. The general multiparametric trends of human threshold performance are discussed, together with the implications for visibility. The importance and implications of observer variance are then explored, with particular reference to their effects on search processes. Finally, attempts are made to highlight the implications of some of the factors on typical radiographic interpretation tasks and on the adequacy of certain types of phantom image used for equipment calibration. (author)

  12. The influence of a continuing education program on the image interpretation accuracy of rural radiographers.

    Science.gov (United States)

    Smith, Tony N; Traise, Peter; Cook, Aiden

    2009-01-01

    In regional, rural and remote clinical practice, radiographers work closely with medical members of the acute care team in the interpretation of radiographic images, particularly when no radiologist is available. However, the misreading of radiographs by non-radiologist physicians has been shown to be the most common type of clinical error in the emergency department. Further, in Australia few rural radiographers are specifically trained to interpret and report on images. This study aimed to evaluate the accuracy of a group of rural radiographers in interpreting musculoskeletal plain radiographs, and to assess the effectiveness of continuing education (CE) in improving their accuracy within a short time frame. Following ethics approval, 16 rural radiographers were recruited to the study. At inception a purpose-designed 'test-object' of 25 cases compiled by a radiologist was used to assess image interpretation accuracy. The cases were categorised into three grades of complexity. The radiographers entered their answers on a structured radiographer opinion form (ROF) that had three levels of response - 'general opinion', 'observations' and 'open comment'. Subsequent to base-line testing, the radiographers participated in a CE program aimed at improving their image interpretation skills. After a 4 month period they were re-tested using the same methodology. The ROFs were scored by the radiologist and the pooled results analysed for statistically significant changes at all ROF levels and grades of complexity. While for the small number of less complex grade 1 cases there was no change in image interpretation accuracy, for the more numerous and more complex grade 2 and grade 3 cases there was a statistically significant improvement at the 'general opinion' and 'observation' levels (paired t-test, p radiologist. However, radiographers' ability to use radiological vocabulary needs improvement. The complementary role that exists between radiographers and other members of

  13. The accuracy of the radiographic method in root canal length measurement

    International Nuclear Information System (INIS)

    Jo, Eun Young; Park, Chang Seo

    1998-01-01

    For the successful endodontic treatment, root canal should be cleaned thoroughly by accurate mechanical and chemical canal preparation and sealed completely with canal filling material without damaging the periapical tissues. The accuracy of the root canal length measurement is a prerequisite for the success of the endodontic treatment, and the root canal length is often determined by the standard periapical radiographs and digital tactile sense. In this study, the accuracy and the clinical usefulness of Digora, an intraoral digital imaging processor and the conventional standard radiographs were compared by measuring the length from the top of the file to the root apex. 30 single rooted premolars were invested in a uniformly sized blocks and No.25 K-file was inserted into and fixed in each canal. Each block was placed in equal distance and position to satisfy the principle of the bisecting angle and paralleling techniques and Digora system's image and standard periapical radiographs were taken. Each radiograph was examined by 3 different observers by measuring the length from top of the file to the root apex and each data was compared and analyzed. The results were as follows; 1. In the bisecting angle technique, the average difference between the Digora system and standard periapical radiograph was 0.002 mm and the standard deviation was 0.341 mm which showed no statistically significant difference between the two systems (p>0.05). Also, in the paralleling technique, the average difference between these two system was 0.007 mm and the standard deviation was 0.323 mm which showed no statistically significant difference between the two systems (p>0.05). 2. In Digora system, the average difference between the bisecting angle and paralleling technique was -0.336 mm and the standard deviation was 0.472 mm which showed a statistically significant difference between the two techniques (p 0.05). In conclusion, the determination of the root canal length by using the

  14. Digitization of radiographic inspection for pipeline girth welded joints

    International Nuclear Information System (INIS)

    Uemura, Shimpei

    2016-01-01

    In radiographic inspection for the girth welded joints of natural gas pipeline, film radiographic testing (FRT) is applied presently in Japan. However, as of July 2016, the work of establishing JIS standard for radiographic inspection with digital detector is in progress. In order to provide users with the merit of digitization as soon as possible, the authors have developed NSDART (Nittetsu-Sumikin digital detector array technology) as a field X-ray inspection system for the girth welded joints of pipeline. This paper reports the required performances discussed in face of development of NSDART, selection of digital detector, and outline of NSDART, and shows part of the radiographic images acquired with NSDART. As required performances, the following were established: (1) required image quality for radiographic image, (2) identifiable minimum wire diameter of transmission meter, (3) density range of radiographic image and value of gradation meter, (4) spatial resolution via Duplex Wire, (5) X-ray generator, (6) real time performance, and (7) display for observing radiographic image. As for the selection of digital detector, flat panel detector was judged to be the most suitable, and its incorporation to NSDART was determined. NSDART devices are composed of a magnet-wheeled self-propelled imaging device, personal computer, controller, and externally installed display for judgment. (A.O.)

  15. Evaluation of trabecular bone patterns on dental radiographic images: influence of cortical bone

    Science.gov (United States)

    Amouriq, Yves; Evenou, Pierre; Arlicot, Aurore; Normand, Nicolas; Layrolle, Pierre; Weiss, Pierre; Guédon, Jean-Pierre

    2010-03-01

    For some authors trabecular bone is highly visible in intraoral radiographs. For other authors, the observed intrabony trabecular pattern is a representation of only the endosteal surface of cortical bone, not of intermedullary striae. The purpose of this preliminary study was to investigate the true anatomical structures that are visible in routine dental radiographs and classically denoted trabecular bone. This is a major point for bone texture analysis on radiographs. Computed radiography (CR) images of dog mandible section in molar region were compared with simulations calculated from high-resolution micro-CT volumes. Calculated simulations were obtained using the Mojette Transform. By digitally editing the CT volume, the simulations were separated into trabecular and cortical components into a region of interest. Different images were compared and correlated, some bone micro-architecture parameters calculated. A high correlation was found between computed radiographs and calculated simulations from micro-CT. The Mojette transform was successful to obtain high quality images. Cortical bone did not contribute to change in a major way simulated images. These first results imply that intrabony trabecular pattern observed on radiographs can not only be a representation of the cortical bone endosteal surface and that trabecular bone is highly visible in intraoral radiographs.

  16. Design and development of a computer based simulator to support learning of radiographic image quality

    Energy Technology Data Exchange (ETDEWEB)

    Costaridou, L; Pitoura, T; Panayiotakis, G; Pallikarakis, N [Department of Medical Physics, School of Medicine, University of Patras, 265 00 Patras (Greece); Hatzis, K [Institute of Biomedical Technology, Ellinos Stratiotou 50A, 264 41 Patras (Greece)

    1994-12-31

    A training simulator has been developed to offer a structured and functional approach to radiographic imaging procedures and comprehensive understanding of interrelations between physical and technical input parameters of a radiographic imaging system and characteristics of image quality. The system addresses training needs of radiographers and radiology clinicians. The simulator is based on procedural simulation enhanced by a hypertextual model of information organization. It is supported by an image data base, which supplies and enriches the simulator. The simulation is controlled by a browsing facility which corresponds to several hierachical levels of use of the underlying multimodal data base, organized as imaging tasks. Representative tasks are : production of a single radiograph or production of functional sets of radiographs exhibiting parameter effects on image characteristics. System parameters such as patient positioning, focus to patient distance, magnification, field dimensions, focal spot size, tube voltage, tube current and exposure time are under user control. (authors). 7 refs, 2 figs.

  17. Design and development of a computer based simulator to support learning of radiographic image quality

    International Nuclear Information System (INIS)

    Costaridou, L.; Pitoura, T.; Panayiotakis, G.; Pallikarakis, N.; Hatzis, K.

    1994-01-01

    A training simulator has been developed to offer a structured and functional approach to radiographic imaging procedures and comprehensive understanding of interrelations between physical and technical input parameters of a radiographic imaging system and characteristics of image quality. The system addresses training needs of radiographers and radiology clinicians. The simulator is based on procedural simulation enhanced by a hypertextual model of information organization. It is supported by an image data base, which supplies and enriches the simulator. The simulation is controlled by a browsing facility which corresponds to several hierachical levels of use of the underlying multimodal data base, organized as imaging tasks. Representative tasks are : production of a single radiograph or production of functional sets of radiographs exhibiting parameter effects on image characteristics. System parameters such as patient positioning, focus to patient distance, magnification, field dimensions, focal spot size, tube voltage, tube current and exposure time are under user control. (authors)

  18. Imperceptible reversible watermarking of radiographic images based on quantum noise masking.

    Science.gov (United States)

    Pan, Wei; Bouslimi, Dalel; Karasad, Mohamed; Cozic, Michel; Coatrieux, Gouenou

    2018-07-01

    Advances in information and communication technologies boost the sharing and remote access to medical images. Along with this evolution, needs in terms of data security are also increased. Watermarking can contribute to better protect images by dissimulating into their pixels some security attributes (e.g., digital signature, user identifier). But, to take full advantage of this technology in healthcare, one key problem to address is to ensure that the image distortion induced by the watermarking process does not endanger the image diagnosis value. To overcome this issue, reversible watermarking is one solution. It allows watermark removal with the exact recovery of the image. Unfortunately, reversibility does not mean that imperceptibility constraints are relaxed. Indeed, once the watermark removed, the image is unprotected. It is thus important to ensure the invisibility of reversible watermark in order to ensure a permanent image protection. We propose a new fragile reversible watermarking scheme for digital radiographic images, the main originality of which stands in masking a reversible watermark into the image quantum noise (the dominant noise in radiographic images). More clearly, in order to ensure the watermark imperceptibility, our scheme differentiates the image black background, where message embedding is conducted into pixel gray values with the well-known histogram shifting (HS) modulation, from the anatomical object, where HS is applied to wavelet detail coefficients, masking the watermark with the image quantum noise. In order to maintain the watermark embedder and reader synchronized in terms of image partitioning and insertion domain, our scheme makes use of different classification processes that are invariant to message embedding. We provide the theoretical performance limits of our scheme into the image quantum noise in terms of image distortion and message size (i.e. capacity). Experiments conducted on more than 800 12 bits radiographic images

  19. Radiographer involvement in mammography image interpretation: A survey of United Kingdom practice

    International Nuclear Information System (INIS)

    Culpan, A.M.

    2016-01-01

    Breast cancer is most often diagnosed using x-ray mammography. Traditionally mammography images have been interpreted and reported by medically qualified practitioners – radiologists. Due to radiologist workforce shortages in recent years some non-medical practitioners, radiographers, now interpret and report mammography images. The aims of this survey were to describe the characteristics and practices of radiographers who interpret and report mammography images in NHS hospitals in the UK, and in particular to establish the extent of their practice beyond low-risk asymptomatic screening cases. This service evaluation demonstrated that UK radiographers are interpreting and reporting images across the full spectrum of clinical indications for mammography including: low-risk population screening, symptomatic, annual surveillance, family history and biopsy/surgical cases. The survey revealed that radiographers are involved in a diverse range of single and double reading practices where responsibility for diagnostic decision making is shared or transferred between radiologists and/or other radiographers. Comparative analysis of sub-group data suggested that there might be differences in the characteristics and practices of radiographers who interpret only low-risk screening mammograms and those who interpret and report a wider range of cases. The findings of this survey provide a platform for further research to investigate how and why the roles and responsibilities of radiographers who interpret and report mammograms vary between organisations, between practitioners and across different examinations. Further research is also needed to explore the implications of variation in practice for patients, practitioners and service providers. - Highlights: • UK radiographers interpret mammograms across the full spectrum of clinical indications. • UK radiographers are involved in a wide range of single/double mammography reading practices. • Characteristics required for

  20. Application of the EM algorithm to radiographic images.

    Science.gov (United States)

    Brailean, J C; Little, D; Giger, M L; Chen, C T; Sullivan, B J

    1992-01-01

    The expectation maximization (EM) algorithm has received considerable attention in the area of positron emitted tomography (PET) as a restoration and reconstruction technique. In this paper, the restoration capabilities of the EM algorithm when applied to radiographic images is investigated. This application does not involve reconstruction. The performance of the EM algorithm is quantitatively evaluated using a "perceived" signal-to-noise ratio (SNR) as the image quality metric. This perceived SNR is based on statistical decision theory and includes both the observer's visual response function and a noise component internal to the eye-brain system. For a variety of processing parameters, the relative SNR (ratio of the processed SNR to the original SNR) is calculated and used as a metric to compare quantitatively the effects of the EM algorithm with two other image enhancement techniques: global contrast enhancement (windowing) and unsharp mask filtering. The results suggest that the EM algorithm's performance is superior when compared to unsharp mask filtering and global contrast enhancement for radiographic images which contain objects smaller than 4 mm.

  1. Comparison of three digital radiographic imaging systems for the visibility of endodontic files

    International Nuclear Information System (INIS)

    Park, Jong Won; Kim, Eun Kyung; Han, Won Jeong

    2004-01-01

    To compare three digital radiographic imaging sensors by evaluating the visibility of endodontic file tips with interobserver reproducibility and assessing subjectively the clarity of images in comparison with the x-ray film images. Forty-five extracted sound premolars were used for this study. Fifteen plaster blocks were made with three premolars each and 8, 10, 15 K-flexofiles were inserted into the root canal of premolars. They were radiographically exposed using periapical x-ray films (Kodak Insight Dental film, Eastmann Kodak company, Rochester, USA), Digora imaging plates (Soredex-Orion Co., Helsinki, Finland), CDX 2000HQ sensors (Biomedisys Co., Seoul, Korea), and CDR sensors (Schick Inc., Long Island, USA). The visibility of endodontic files was evaluated with interobserver reproducibility, which was calculated as the standard deviations of X, Y coordinated of endodontic file tips measured on digital images by three oral and maxillofacial radiologists. The clarity of images was assessed subjectively using 3 grades, i.e, plus, equal, and minus in comparison with the conventional x-ray film images. Interobserver reproducibility of endodontic file tips was the highest in CDR sensor (p<0.05) only except at Y coordinates of 15 file. In the subjective assessment of the image clarity, the plus grade was the most frequent in CDR sensor at all size of endodontic file (p<0.05). CDR sensor was the most superior to the other sensors, CDX 2000HQ sensor and Digora imaging plate in the evaluation of interobserver reproducibility of endodontic file tip and subjective assessment of image clarity.

  2. Implementation of a dedicated digital projectional radiographic system in thoracic imaging

    International Nuclear Information System (INIS)

    Aberle, D.R.; Batra, P.; Hayrapetian, A.S.; Brown, K.; Morioka, C.A.; Steckel, R.J.

    1988-01-01

    An integrated digital radiographic system was evaluated with respect to image quality and impact on diagnosis relative to conventional chest radiographs for a variety of focal and diffuse lung processes. Digital images were acquired with a stimulable phosphor plate detector that was scanned by a semiconductor laser for immediate digitalization to a 2,048 X 2,464 X 10-bit image. Digital images were displayed on a 2,048-line monitor and printed on 14 X 17-inch film with use of a laser film printer (Kodak). Preliminary results with this system, including the effects of user interaction with the display monitor, inverse intensity display, and regional magnification techniques, indicate that it may be successfully implemented for thoracic imaging

  3. Performance of a thermal neutron radiographic system using imaging plates

    International Nuclear Information System (INIS)

    Silvani, Maria Ines; Almeida, Gevaldo L. de; Furieri, Rosanne; Lopes, Ricardo T.

    2009-01-01

    A performance evaluation of a neutron radiographic system equipped with a thermal neutron sensitive imaging plate has been undertaken. It includes the assessment of spatial resolution, linearity, dynamic range and the response to exposure time, as well as a comparison of these parameters with the equivalent ones for neutron radiography employing conventional films and a gadolinium foil as converter. The evaluation and comparison between the radiographic systems have been performed at the Instituto de Engenharia Nuclear - CNEN, using the Argonauta Reactor as source of thermal neutrons and a commercially available imaging plate reader. (author)

  4. Method for producing three-dimensional real image using radiographic perspective views of an object

    International Nuclear Information System (INIS)

    Ellingson, W.A.; Read, A.A.

    1976-01-01

    A sequence of separate radiographs may be made by indexing a radiation source along a known path relative to the object under study. Thus, each radiograph contains information from a different perspective. A holographically-recorded image is then made from each radiographic perspective by exact re-tracing of the rays through each radiographic perspective such that the re-tracing duplicates the geometry under which it was originally prepared. The holographically-stored images are simultaneously illuminated with the conjugate of the reference beam used in the original recordings. The result is the generation of a three-dimensional real image of the object such that a light-sensitive device can be moved to veiw the real image along any desired surface with the optical information in all other surfaces greatly suppressed. 4 claims, 5 drawing figures

  5. Neonatal chest image quality addressed through training to enhance radiographer awareness

    Directory of Open Access Journals (Sweden)

    Hesta Friedrich-Nel

    2018-03-01

    Full Text Available Background: Diagnostic radiographers working in the neonatal intensive care unit primarily aim to produce an image of optimal quality using optimal exposure techniques without repeating exposures, to keep neonatal radiation dose to a minimum.   Objectives: The aim of the study was to determine whether radiographers were producing optimal quality chest images and, if not, whether additional training could contribute to reaching this goal in the Free State Province of South Africa.   Methods: Neonatal chest image quality was determined in the Neonatal Intensive Care Unit by using a checklist based on and compiled from published guidelines to evaluate the quality of 450 randomly-selected images. Thereafter, a training programme was designed, based on the evaluation criteria of the checklist and image quality areas identified. The training also referred to positioning techniques that should be applied to ensure optimal image quality. After presentation of the training, 450 newly-produced neonatal chest images were evaluated. These images were selected through purposive sampling as this evaluation only included images of participating radiographers who completed the training.   Results: Image quality that showed significant improvement included a reduction in electrocardiogram lines superimposed on chest anatomy, a tendency to centre closer to thoracic vertebra four, and visible four-sided collimation on images. Image quality areas with no significant enhancement were the absence of lead markers and radiation shielding.   Conclusion: The study has shown that a training programme has the potential to improve neonatal chest image quality.

  6. Comparison of JPEG and wavelet compression on intraoral digital radiographic images

    International Nuclear Information System (INIS)

    Kim, Eun Kyung

    2004-01-01

    To determine the proper image compression method and ratio without image quality degradation in intraoral digital radiographic images, comparing the discrete cosine transform (DCT)-based JPEG with the wavelet-based JPEG 2000 algorithm. Thirty extracted sound teeth and thirty extracted teeth with occlusal caries were used for this study. Twenty plaster blocks were made with three teeth each. They were radiographically exposed using CDR sensors (Schick Inc., Long Island, USA). Digital images were compressed to JPEG format, using Adobe Photoshop v. 7.0 and JPEG 2000 format using Jasper program with compression ratios of 5 : 1, 9 : 1, 14 : 1, 28 : 1 each. To evaluate the lesion detectability, receiver operating characteristic (ROC) analysis was performed by the three oral and maxillofacial radiologists. To evaluate the image quality, all the compressed images were assessed subjectively using 5 grades, in comparison to the original uncompressed images. Compressed images up to compression ratio of 14: 1 in JPEG and 28 : 1 in JPEG 2000 showed nearly the same the lesion detectability as the original images. In the subjective assessment of image quality, images up to compression ratio of 9 : 1 in JPEG and 14 : 1 in JPEG 2000 showed minute mean paired differences from the original images. The results showed that the clinically acceptable compression ratios were up to 9 : 1 for JPEG and 14 : 1 for JPEG 2000. The wavelet-based JPEG 2000 is a better compression method, comparing to DCT-based JPEG for intraoral digital radiographic images.

  7. The reliability of tablet computers in depicting maxillofacial radiographic landmarks

    Energy Technology Data Exchange (ETDEWEB)

    Tadinada, Aditya; Mahdian, Mina; Sheth, Sonam; Chandhoke, Taranpreet K.; Gopalakrishna, Aadarsh; Potluri, Anitha; Yadav, Sumit [University of Connecticut School of Dental Medicine, Farmington (United States)

    2015-09-15

    This study was performed to evaluate the reliability of the identification of anatomical landmarks in panoramic and lateral cephalometric radiographs on a standard medical grade picture archiving communication system (PACS) monitor and a tablet computer (iPad 5). A total of 1000 radiographs, including 500 panoramic and 500 lateral cephalometric radiographs, were retrieved from the de-identified dataset of the archive of the Section of Oral and Maxillofacial Radiology of the University Of Connecticut School Of Dental Medicine. Major radiographic anatomical landmarks were independently reviewed by two examiners on both displays. The examiners initially reviewed ten panoramic and ten lateral cephalometric radiographs using each imaging system, in order to verify interoperator agreement in landmark identification. The images were scored on a four-point scale reflecting the diagnostic image quality and exposure level of the images. Statistical analysis showed no significant difference between the two displays regarding the visibility and clarity of the landmarks in either the panoramic or cephalometric radiographs. Tablet computers can reliably show anatomical landmarks in panoramic and lateral cephalometric radiographs.

  8. Radiographer interpretation of trauma radiographs: Issues for radiography education providers

    International Nuclear Information System (INIS)

    Hardy, Maryann; Snaith, Beverly

    2009-01-01

    Background: The role of radiographers with respect to image interpretation within clinical practice is well recognised. It is the expectation of the professional, regulatory and academic bodies that upon qualification, radiographers will possess image interpretation skills. Additionally, The College of Radiographers has asserted that its aspiration is for all radiographers to be able to provide an immediate written interpretation on skeletal trauma radiographs by 2010. This paper explores the readiness of radiography education programmes in the UK to deliver this expectation. Method: A postal questionnaire was distributed to 25 Higher Education Institutions in the UK (including Northern Ireland) that provided pre-registration radiography education as identified from the Society and College of Radiographers register. Information was sought relating to the type of image interpretation education delivered at pre- and post-registration levels; the anatomical range of image interpretation education; and education delivery styles. Results: A total of 19 responses (n = 19/25; 76.0%) were received. Image interpretation education was included as part of all radiographer pre-registration programmes and offered at post-registration level at 12 academic centres (n = 12/19; 63.2%). The anatomical areas and educational delivery methods varied across institutions. Conclusion: Radiography education providers have embraced the need for image interpretation education within both pre- and post-registration radiography programmes. As a result, UK education programmes are able to meet the 2010 College of Radiographers aspiration.

  9. Radiographic imaging study of pneumocystis carinii pneumonia in renal transplantation recipient

    International Nuclear Information System (INIS)

    Chen Chengshui; Li Yuping; Ye Min; Zhang Dongqing; Zheng Shaoling; Xing Lingling; Chen Shaoxian

    2005-01-01

    Objective: To improve the understanding of the imaging features of pneumocystis carinii pneumonia (PCP) in renal transplantation recipient. Methods: Twenty-four renal transplantation recipients suffered from PCP. There were 19 males and 5 females, the age ranged from 23 to 62 years (mean 39.2 years). The mean time duration from renal transplantation to onset of illness was 5.6 months, and the mean time from onset of illness to consultation was 5.5 days. All patients had fever and dyspnea. The chest radiographic imaging was reviewed and the dynamic imaging changes were followed up. Results: Pathology showed alveolar exudation, inflammation in the interstitium and alveolar lumen, fibrosis in lung interstitium, and erosion of alveolar epithelium. Initial chest X-ray demonstrated diffuse changes in only 10 patients. Of the 10 patients, 3 showed ground-glass changes, 2 showed ground-glass and reticular changes, and 4 showed consolidation. But all patients had abnormal ill-defined ground-glass findings on thoracic CT images, 9 of them showed reticulum among ground-glass changes, and 12 of them showed consolidation among ground-glass changes. Among patients with clinical deterioration, chest radiographs and CT showed progression of pulmonary infiltrations, and it reached the top level within 1 to 2 weeks. With successful response to therapy, chest radiographs and CT showed resolution of the lung opacities, but the resolution was retarded for about 1 week, complete resolution would need 4 weeks. Conclusion: The radiographic imaging features of PCP in renal transplantation recipient were diffuse interstitial alterations and consolidations, and with fast progression. With successful response to therapy, it showed resolution of the lung opacities, but the resolution was retarded for about 1 week, and complete resolution would need 4 weeks. Chest CT was more sensitive than radiographs. (authors)

  10. Radiographic interpretation of the appendicular skeleton: A comparison between casualty officers, nurse practitioners and radiographers

    International Nuclear Information System (INIS)

    Coleman, Liz; Piper, Keith

    2009-01-01

    Aim: To assess how accurately and confidently casualty officers, nurse practitioners and radiographers, practicing within the emergency department (ED), recognize and describe radiographic trauma within an image test bank of 20 appendicular radiographs. Method: The participants consisted of 7 casualty officers, 13 nurse practitioners and 18 radiographers. All 20 radiographic examinations selected for the image test bank had been acquired following trauma and included some subtle, yet clinically significant abnormalities. The test bank score (maximum 40 marks), sensitivity and specificity percentages were calculated against an agreed radiological diagnosis (reference standard). Alternative Free-response Receiver Operating Characteristic (AFROC) analysis was used to assess the overall performance of the diagnostic accuracy of these professional groups. The variation in performance between each group was measured using the analysis of variance (ANOVA) test, to identify any statistical significant differences in the performance in interpretation between these groups. The relationship between the participants' perceived image interpretation accuracy during clinical practice and the actual accuracy of their image test bank score was examined using Pearson's Correlation Coefficient (r). Results: The results revealed that the radiographers gained the highest mean test bank score (28.5/40; 71%). This score was statistically higher than the mean test bank scores attained by the participating nurse practitioners (21/40; 53%) and casualty officers (21.5/40; 54%), with p < 0.01 and p = 0.02, respectively. When compared with each other, the scores from these latter groups showed no significant difference (p = 0.91). The mean 'area under the curve' (AUC) value achieved by the radiographers was also significantly higher (p < 0.01) in comparison to the AUC values demonstrated by the nurse practitioners and casualty officers, whose results, when compared, showed no significant

  11. Reassessing the standard chest radiograph for intraparenchymal activity

    International Nuclear Information System (INIS)

    Putman, C.E.; Hoeck, B.

    1986-01-01

    Despite the recent enthusiasm for better means of determining the extent of the active inflammatory response in the lung parenchyma of sarcoidosis patients, standard chest radiography remains a reliable method of determining staging, and parenchymal activity as well. The chest radiograph is characteristically used to determine the severity and course of sarcoidosis, but most studies imply there are poor correlations between the radiographic opacities and other indicators such as physiological parameters, gallium scans, and computed tomography and bronchoalveolar lavage results. In this preliminary communication, the authors report a new method of determining sarcoidosis activity, as compared to gallium scan, based solely on the standard chest radiograph. This method is based on the presence or absence of air bronchogram abnormalities, peribronchial cuffing, and subpleural thickening. Adenopathy and linear, reticulonodular, and nodular opacities are not included in this system. In 85 recent studies, which were performed in 51 patients with biopsy-proven sarcoidosis, this staging method agreed with gallium scanning in 68.2% of the patients. This system failed in specific and identifiable subgroups of patients that we will delineate. The authors will not report the comparative indices with a pulmonary function analysis or bronchoalveolar lavage results. Their database has not been tabulated to conclusively present these results, but it is their belief that this methodology will probably have a better correlation with lavage results and small airway function than would results of gallium scans. Of singular importance is the fact that this method can, with a more than acceptable degree of accuracy, distinguish between ''low-intensity'' alveolitis and ''high-intensity'' alveolitis

  12. Automated matching of corresponding seed images of three simulator radiographs to allow 3D triangulation of implanted seeds

    Science.gov (United States)

    Altschuler, Martin D.; Kassaee, Alireza

    1997-02-01

    To match corresponding seed images in different radiographs so that the 3D seed locations can be triangulated automatically and without ambiguity requires (at least) three radiographs taken from different perspectives, and an algorithm that finds the proper permutations of the seed-image indices. Matching corresponding images in only two radiographs introduces inherent ambiguities which can be resolved only with the use of non-positional information obtained with intensive human effort. Matching images in three or more radiographs is an `NP (Non-determinant in Polynomial time)-complete' problem. Although the matching problem is fundamental, current methods for three-radiograph seed-image matching use `local' (seed-by-seed) methods that may lead to incorrect matchings. We describe a permutation-sampling method which not only gives good `global' (full permutation) matches for the NP-complete three-radiograph seed-matching problem, but also determines the reliability of the radiographic data themselves, namely, whether the patient moved in the interval between radiographic perspectives.

  13. The effect of aluminium screen on the quality of radiographic image using x-radiation

    International Nuclear Information System (INIS)

    Azali Muhammad; Azhar Azmi; Mohd Soot Ahmad; Hafizul Abd Ghani

    2002-01-01

    The effect of different thickness of aluminium screen on the quality of radiographic image and the exposure time have been studied. The specimen used was based on the steel step wedge having thickness ranging from minimum 10 mm up to maximum 15 mm. The specimen was exposed to 100 kV up to 190 kV x-radiation by using single wall single image (SWSI) radiographic technique. The radiographic film D7 used in this study, which sandwiched with metallic screen made of aluminium, or lead was inserted into flexible cassette. The quality of the radiograph was then evaluated by observing the appearance of DIN wire type image quality indicator (IQI) 10ISO16 and the density difference (ΔD) of two adjacent steps on the radiograph, i.e. the subject contrast. The result shows that at a certain applied voltage (kV), the used of different thickness of aluminium screens give significant effect on the Δ D. Besides that the radiographic image quality in term of visibility of the smallest wire of IQI on radiograph also increases with decreasing kV for all types of aluminium screen. It is observed as well the effect of thickness of aluminium screen on subject contrast depends on the kV, i.e. for kV ranging from 100 up to 190 kV the subject contrast increases with increasing thickness of aluminium screen. The comparison of these results with radiograph using lead screen was also presented in this paper. (Author)

  14. Development of automatic radiographic inspection system using digital image processing and artificial intelligence

    International Nuclear Information System (INIS)

    Itoga, Kouyu; Sugimoto, Koji; Michiba, Koji; Kato, Yuhei; Sugita, Yuji; Onda, Katsuhiro.

    1991-01-01

    The application of computers to welding inspection is expanding rapidly. The classification of the application is the collection, analysis and processing of data, the graphic display of results, the distinction of the kinds of defects and the evaluation of the harmufulness of defects and the judgement of acceptance or rejection. The application of computer techniques to the automation of data collection was realized at the relatively early stage. Data processing and the graphic display of results are the techniques in progress now, and the application of artificial intelligence to the distinction of the kinds of defects and the evaluation of harmfulness is expected to expand rapidly. In order to computerize radiographic inspection, the abilities of image processing technology and knowledge engineering must be given to computers. The object of this system is the butt joints by arc welding of the steel materials of up to 30 mm thickness. The digitizing transformation of radiographs, the distinction and evaluation of transmissivity and gradation by image processing, and only as for those, of which the picture quality satisfies the standard, the extraction of defect images, their display, the distinction of the kinds and the final judgement are carried out. The techniques of image processing, the knowledge for distinguishing the kinds of defects and the concept of the practical system are reported. (K.I.)

  15. Influence of the intergonial distance on image distortion in panoramic radiographs.

    Science.gov (United States)

    Ladeira, D B S; Cruz, A D; Almeida, S M; Bóscolo, F N

    2012-07-01

    The aim of this study was to evaluate the influence of the intergonial distance during the formation of panoramic radiographic images by means of horizontal and vertical measurements. 30 macerated mandibles were categorized into 3 different groups (n = 10) according to their intergonial distances as follows: G1, mean distance 8.2 cm, G2, mean distance 9.0 cm and G3, mean distance 9.6 cm. Three metal spheres 0.198 cm in diameter and placed at an incline using an isosceles triangle were separately placed over the internal and external surfaces of the mandibles before radiographic exposure for the purpose of taking the horizontal and vertical measurements. The occlusal planes of the mandibles were horizontally placed on the chin rest of the panoramic machine Orthopantomograph® OP 100 (Instrumentarium Imaging, Tuusula, Finland) and were then radiographed. In the panoramic radiographs, an expert radiologist measured the distances between the metal spheres in the horizontal and vertical directions using a digital caliper. The data were tabled and statistically analysed by Student's t-test and analysis of variance with Tukey post-test (α = 0.05). In all three groups magnification of the distances between spheres was observed when compared with the real distance in both horizontal and vertical measurements (p 0.05). Differences between horizontal and vertical measurements were observed in different regions in all evaluated groups (p image formation in the panoramic radiograph.

  16. Sonographic Imaging of Meniscal Subluxation in Patients with Radiographic Knee Osteoarthritis

    Directory of Open Access Journals (Sweden)

    Chun-Hung Ko

    2007-09-01

    Conclusion: Meniscal subluxation is a prominent feature on weight-bearing sonographic imaging in patients with radiographic osteoarthritis and could be considered as a risk factor for the development of knee osteoarthritis. By using musculoskeletal ultrasonography, one can detect this occult meniscal derangement early before the appearance of radiographic signs of osteoarthritis.

  17. Current role of the radiographers in imaging diagnostics, nuclear medicine and radiotherapy in modern departments

    International Nuclear Information System (INIS)

    Karidova, S.; Velkova, K.; Panamska, K.; Petkova, K.

    2006-01-01

    Full text: In the communication we set out to focus the attention of the medical staff and the public on the place and the constantly growing role (relative burden) of the radiographers in imaging diagnostics, nuclear medicine and radiotherapy in the field of modern medicine. The advanced radiographers level and rapid development of the contemporary equipment and apparatuses used in imaging diagnostics, nuclear medicine and radiotherapy, as well as the methods of their utilization, presuppose very good and constantly improving theoretical and practical training of the imaging technician. The radiographer fulfills responsible tasks under the guidance of the physician or independently and bears specific responsibilities. Having mastered the fundamentals of radiation protection, the imaging technician protects both himself and the patient from the impact of ionizing radiation. To be able to fulfill his/her constantly increasing duties and obligations, the imaging radiographer has acquired wide knowledge of general education subjects, subjects of general medicine and special subjects. The radiographer has a good knowledge of Latin and a modern foreign language, and he is also computer literate so as to be able to cope with the widely spread visualizing methods. The radiographer acquires additional post-graduate training to work in narrowly specialized fields as well as to improve his/her qualifications

  18. Performance evaluation of the EM algorithm applied to radiographic images

    International Nuclear Information System (INIS)

    Brailean, J.C.; Giger, M.L.; Chen, C.T.; Sullivan, B.J.

    1990-01-01

    In this paper the authors evaluate the expectation maximization (EM) algorithm, both qualitatively and quantitatively, as a technique for enhancing radiographic images. Previous studies have qualitatively shown the usefulness of the EM algorithm but have failed to quantify and compare its performance with those of other image processing techniques. Recent studies by Loo et al, Ishida et al, and Giger et al, have explained improvements in image quality quantitatively in terms of a signal-to-noise ratio (SNR) derived from signal detection theory. In this study, we take a similar approach in quantifying the effect of the EM algorithm on detection of simulated low-contrast square objects superimposed on radiographic mottle. The SNRs of the original and processed images are calculated taking into account both the human visual system response and the screen-film transfer function as well as a noise component internal to the eye-brain system. The EM algorithm was also implemented on digital screen-film images of test patterns and clinical mammograms

  19. Post-graduate training in imaging diagnostics, nuclear medicine and radiotherapy for radiographers

    International Nuclear Information System (INIS)

    Petkova, E.; Velkova, K.; Shangova, M.; Karidova, S.

    2006-01-01

    Full text: The application of new technologies in imaging diagnostics, as well as the use of digital processing and storing of information, has increased the quality and scope of imaging diagnostics. The potentials of therapeutic methods connected with imaging diagnostics and nuclear medicine, interventional therapeutic procedures (dilatation, embolism, stent, etc.), basins with radio-pharmaceuticals, etc., are constantly increasing. The constant training of radiographers in working with the new, advanced image-diagnostic equipment has become an established international practice in the process of training the human resources of the imaging-diagnostic departments and centers. Objectives: 1. Investigating the potentials of post-graduate training for monitoring the dynamics in the development of the principles, methods and techniques in imaging diagnostics; 2. The attitude of radiographers towards post-graduate training. Systematic approach and critical analysis of published data and mathematical-statistical methods with regard to the need of post-graduate training. The processed data of the survey on the necessity for post-graduate training conducted among 3rd year students in the last 3 years - 75 % consider post-graduate training mandatory, 11% deem it necessary, and 14% have no opinion on the issue; and among the working radiographers in the last 3 years the results are as follows: mandatory - 91%, necessary - 7%, no opinion - 2%. The improvement and advances in imaging diagnostic equipment and apparatuses have considerably outstripped the professional training of radiographers. The key word in the race for knowledge is constant learning and training, which can successfully be achieved within the framework of post-graduate training

  20. Field-Based Radiographic Imaging of Marine Megafauna: Marine Iguanas (Amblyrhynchus cristatus as a Case Study

    Directory of Open Access Journals (Sweden)

    Gregory A. Lewbart

    2018-02-01

    Full Text Available Effective conservation of marine megafauna requires a thorough understanding of the ecology, physiology, population dynamics, and health of vulnerable species. Assessing the health of large, mobile marine animals poses particular challenges, in part because the subjects are difficult to capture and restrain, and in part because standard laboratory and diagnostic tools are difficult to apply in a field setting. Radiography is a critically important diagnostic tool used routinely by veterinarians, but it has seldom been possible to image live marine vertebrates in the field. As a first step toward assessing the feasibility of incorporating radiography into studies of vulnerable species in remote locations, we used portable radiographic equipment to acquire the first digital internal images of living marine iguanas, Amblyrhynchus cristatus, an iconic lizard endemic only to the Galápagos Islands of Ecuador. The radiographic machinery was powered by batteries and performed well on a rocky beach environment of an uninhabited island, despite high heat and humidity. The accuracy of radiographic measurements was validated by computing a snout-vent length (SVL using bone dimensions and comparing this to standard measurements of SVL made externally with a tape measure. These results demonstrate the feasibility of using radiography to study animals in remote sites, a technique that may prove useful for a variety of physiological, ecological, and biomechanical studies in which reliable measurements of skeletal and soft-tissue dimensions must be acquired under challenging field conditions. Refinements are discussed that will help the technology reach its full potential in field studies.

  1. Radiographic imaging system for high energy radiation

    International Nuclear Information System (INIS)

    Barrett, H.H.

    1976-01-01

    A radiographic imaging system for high energy radiation utilizing a detector of such radiation and a mask having regions relatively transparent to such radiation interspersed among regions relatively opaque to such radiation is described. A relative motion is imparted between the mask and the detector, the detector providing a time varying signal in response to the incident radiation and in response to the relative motion. The time varying signal provides, with the aid of a decoder, an image of a source of such radiation

  2. Radiographic imaging system for high energy radiation

    International Nuclear Information System (INIS)

    1975-01-01

    A radiographic imaging system for high energy radiation is described utilizing a detector of such radiation and a mask having regions relatively transparent to such radiation and interspersed among regions relatively opaque to such radiation. A relative motion is imparted between the mask and the detector, the detector providing a time varying signal in response to the incident radiation and in response to the relative motion. The time varying signal provides, with the aid of a decoder, an image of a source of such radiation

  3. An image correlation procedure for digitally reconstructed radiographs and electronic portal images

    International Nuclear Information System (INIS)

    Dong, Lei; Boyer, Arthur L.

    1995-01-01

    Purpose: To study a procedure that uses megavoltage digitally reconstructed radiographs (DRRs) calculated from patient's three-dimensional (3D) computed tomography (CT) data as a reference image for correlation with on-line electronic portal images (EPIs) to detect patient setup errors. Methods and Materials: Megavoltage DRRs were generated by ray tracing through a modified volumetric CT data set in which CT numbers were converted into linear attenuation coefficients for the therapeutic beam energy. The DRR transmission image was transformed to the grayscale window of the EPI by a histogram-matching technique. An alternative approach was to calibrate the transmission DRR using a measured response curve of the electronic portal imaging device (EPID). This forces the calculated transmission fluence values to be distributed in the same range as that of the EPID image. A cross-correlation technique was used to determine the degree of alignment of the patient anatomy found in the EPID image relative to the reference DRR. Results: Phantom studies demonstrated that the correlation procedure had a standard deviation of 0.5 mm and 0.5 deg. in aligning translational shifts and in-plane rotations. Systematic errors were found between a reference DRR and a reference EPID image. The automated grayscale image-correlation process was completed within 3 s on a workstation computer or 12 s on a PC. Conclusion: The alignment procedure allows the direct comparison of a patient's treatment portal designed with a 3D planning computer with a patient's on-line portal image acquired at the treatment unit. The image registration process is automated to the extent that it requires minimal user intervention, and it is fast and accurate enough for on-line clinical applications

  4. Computed image analysis of neutron radiographs

    International Nuclear Information System (INIS)

    Dinca, M.; Anghel, E.; Preda, M.; Pavelescu, M.

    2008-01-01

    Similar with X-radiography, using neutron like penetrating particle, there is in practice a nondestructive technique named neutron radiology. When the registration of information is done on a film with the help of a conversion foil (with high cross section for neutrons) that emits secondary radiation (β,γ) that creates a latent image, the technique is named neutron radiography. A radiographic industrial film that contains the image of the internal structure of an object, obtained by neutron radiography, must be subsequently analyzed to obtain qualitative and quantitative information about the structural integrity of that object. There is possible to do a computed analysis of a film using a facility with next main components: an illuminator for film, a CCD video camera and a computer (PC) with suitable software. The qualitative analysis intends to put in evidence possibly anomalies of the structure due to manufacturing processes or induced by working processes (for example, the irradiation activity in the case of the nuclear fuel). The quantitative determination is based on measurements of some image parameters: dimensions, optical densities. The illuminator has been built specially to perform this application but can be used for simple visual observation. The illuminated area is 9x40 cm. The frame of the system is a comparer of Abbe Carl Zeiss Jena type, which has been adapted to achieve this application. The video camera assures the capture of image that is stored and processed by computer. A special program SIMAG-NG has been developed at INR Pitesti that beside of the program SMTV II of the special acquisition module SM 5010 can analyze the images of a film. The major application of the system was the quantitative analysis of a film that contains the images of some nuclear fuel pins beside a dimensional standard. The system was used to measure the length of the pellets of the TRIGA nuclear fuel. (authors)

  5. Segmentation of radiographic images under topological constraints: application to the femur.

    Science.gov (United States)

    Gamage, Pavan; Xie, Sheng Quan; Delmas, Patrice; Xu, Wei Liang

    2010-09-01

    A framework for radiographic image segmentation under topological control based on two-dimensional (2D) image analysis was developed. The system is intended for use in common radiological tasks including fracture treatment analysis, osteoarthritis diagnostics and osteotomy management planning. The segmentation framework utilizes a generic three-dimensional (3D) model of the bone of interest to define the anatomical topology. Non-rigid registration is performed between the projected contours of the generic 3D model and extracted edges of the X-ray image to achieve the segmentation. For fractured bones, the segmentation requires an additional step where a region-based active contours curve evolution is performed with a level set Mumford-Shah method to obtain the fracture surface edge. The application of the segmentation framework to analysis of human femur radiographs was evaluated. The proposed system has two major innovations. First, definition of the topological constraints does not require a statistical learning process, so the method is generally applicable to a variety of bony anatomy segmentation problems. Second, the methodology is able to handle both intact and fractured bone segmentation. Testing on clinical X-ray images yielded an average root mean squared distance (between the automatically segmented femur contour and the manual segmented ground truth) of 1.10 mm with a standard deviation of 0.13 mm. The proposed point correspondence estimation algorithm was benchmarked against three state-of-the-art point matching algorithms, demonstrating successful non-rigid registration for the cases of interest. A topologically constrained automatic bone contour segmentation framework was developed and tested, providing robustness to noise, outliers, deformations and occlusions.

  6. Segmentation of radiographic images under topological constraints: application to the femur

    International Nuclear Information System (INIS)

    Gamage, Pavan; Xie, Sheng Quan; Delmas, Patrice; Xu, Wei Liang

    2010-01-01

    A framework for radiographic image segmentation under topological control based on two-dimensional (2D) image analysis was developed. The system is intended for use in common radiological tasks including fracture treatment analysis, osteoarthritis diagnostics and osteotomy management planning. The segmentation framework utilizes a generic three-dimensional (3D) model of the bone of interest to define the anatomical topology. Non-rigid registration is performed between the projected contours of the generic 3D model and extracted edges of the X-ray image to achieve the segmentation. For fractured bones, the segmentation requires an additional step where a region-based active contours curve evolution is performed with a level set Mumford-Shah method to obtain the fracture surface edge. The application of the segmentation framework to analysis of human femur radiographs was evaluated. The proposed system has two major innovations. First, definition of the topological constraints does not require a statistical learning process, so the method is generally applicable to a variety of bony anatomy segmentation problems. Second, the methodology is able to handle both intact and fractured bone segmentation. Testing on clinical X-ray images yielded an average root mean squared distance (between the automatically segmented femur contour and the manual segmented ground truth) of 1.10 mm with a standard deviation of 0.13 mm. The proposed point correspondence estimation algorithm was benchmarked against three state-of-the-art point matching algorithms, demonstrating successful non-rigid registration for the cases of interest. A topologically constrained automatic bone contour segmentation framework was developed and tested, providing robustness to noise, outliers, deformations and occlusions. (orig.)

  7. Segmentation of radiographic images under topological constraints: application to the femur

    Energy Technology Data Exchange (ETDEWEB)

    Gamage, Pavan; Xie, Sheng Quan [University of Auckland, Department of Mechanical Engineering (Mechatronics), Auckland (New Zealand); Delmas, Patrice [University of Auckland, Department of Computer Science, Auckland (New Zealand); Xu, Wei Liang [Massey University, School of Engineering and Advanced Technology, Auckland (New Zealand)

    2010-09-15

    A framework for radiographic image segmentation under topological control based on two-dimensional (2D) image analysis was developed. The system is intended for use in common radiological tasks including fracture treatment analysis, osteoarthritis diagnostics and osteotomy management planning. The segmentation framework utilizes a generic three-dimensional (3D) model of the bone of interest to define the anatomical topology. Non-rigid registration is performed between the projected contours of the generic 3D model and extracted edges of the X-ray image to achieve the segmentation. For fractured bones, the segmentation requires an additional step where a region-based active contours curve evolution is performed with a level set Mumford-Shah method to obtain the fracture surface edge. The application of the segmentation framework to analysis of human femur radiographs was evaluated. The proposed system has two major innovations. First, definition of the topological constraints does not require a statistical learning process, so the method is generally applicable to a variety of bony anatomy segmentation problems. Second, the methodology is able to handle both intact and fractured bone segmentation. Testing on clinical X-ray images yielded an average root mean squared distance (between the automatically segmented femur contour and the manual segmented ground truth) of 1.10 mm with a standard deviation of 0.13 mm. The proposed point correspondence estimation algorithm was benchmarked against three state-of-the-art point matching algorithms, demonstrating successful non-rigid registration for the cases of interest. A topologically constrained automatic bone contour segmentation framework was developed and tested, providing robustness to noise, outliers, deformations and occlusions. (orig.)

  8. Ultra-high-resolution photoelectronic digital radiographic imaging system for medicine

    International Nuclear Information System (INIS)

    Bamford, B.R.; Nudelman, S.; Quimette, D.R.; Ovitt, T.W.; Reisken, A.B.; Spackman, T.J.; Zaccheo, T.S.

    1989-01-01

    The authors report the development of a new type of digital radiographic imaging system for medicine. Unlike previous digital radiographic systems that could not match the spatial resolution of film-screen systems, this system has higher spatial resolution and wider dynamic range than film-screen-based systems. There are three components to the system: a microfocal spot x-ray tube, a camera consisting of a Tektronix TK-2048M 2048 x 2048 CCD image sensor in direct contact with a Kodak Min-R intensifying screen, and a Gould IP-9000 with 2048 x 2048 processing and display capabilities. The CCD image sensor is a large-area integrated circuit and is 55.3 mm x 55.3 mm. It has a linear dynamic range of 12 bits or 4,096 gray levels

  9. Survey of image quality and patient dose in simple radiographic examinations: establishing guidance levels and comparison with international standards

    International Nuclear Information System (INIS)

    Manatrakul, N.; Bunsoong, T.; Krisanachinda, A.; Suwanpradit, P.; Rungruengthanakit, P.; Kanchart, S.; Chaiwong, Rajikorn; Tsapakig, V.A.

    2008-01-01

    Purpose: To investigate image quality and patient dose for commonly radiographic examinations in Thailand, to establish national reference or guidance levels (GL) and compare with international standards, as part of an International Atomic Energy Agency (IAEA) project on Radiation Protection of Patients and Medical Exposure Control (RAS/9/034 and RAS/9/047). Materials and Methods: Film reject rate analysis, image quality and patient dose assessment before and after Quality Control (QC) implementation were investigated in 8 X-ray machines in 4 hospitals. Air kerma (in mGy) at 1 meter focus-detector-distance for different kVp settings for each X-ray machines were measured using an ionization chamber under standardized condition. The entrance skin air kerma (ESAK) for Chest PA, Lumbar spine AP, Lumbar spine LAT, Pelvis AP, Abdomen AP, Skull AP and Skull LAT were calculated for at least 10 adult patients of average body mass (60 to 80 kg) for each projection. The obtained values were compared with international standards. Results: The highest film rejection rate reduction recorded after corrective actions from 9.15% to 6.8%. Mean ESAK values were less than international standards both before and after QC implementation in all projections but Chest PA projection. Maximum ESAK in Chest PA projection before corrective action was 0.55 mGy which was higher than the IAEA GL of 0.2 mGy. However, it was reduced to 0.25 mGy after QC tests on X- ray machine and using high kilovoltage (kV) technique. Conclusion: Proposed national GL of Thailand were obtained by estimating the 3rd quartile of the whole sample: Chest PA: 0.1 mGy, Lumbar Spine AP: 2.1 mGy, Lumbar Spine LAT: 6.3 mGy, Pelvis AP: 1.8 mGy, Abdomen: 1.5 mGy, Skull PA: 1.3 mGy and Skull LAT: 0.9 mGy. (author)

  10. 2D-3D radiograph to cone-beam computed tomography (CBCT) registration for C-arm image-guided robotic surgery.

    Science.gov (United States)

    Liu, Wen Pei; Otake, Yoshito; Azizian, Mahdi; Wagner, Oliver J; Sorger, Jonathan M; Armand, Mehran; Taylor, Russell H

    2015-08-01

    C-arm radiographs are commonly used for intraoperative image guidance in surgical interventions. Fluoroscopy is a cost-effective real-time modality, although image quality can vary greatly depending on the target anatomy. Cone-beam computed tomography (CBCT) scans are sometimes available, so 2D-3D registration is needed for intra-procedural guidance. C-arm radiographs were registered to CBCT scans and used for 3D localization of peritumor fiducials during a minimally invasive thoracic intervention with a da Vinci Si robot. Intensity-based 2D-3D registration of intraoperative radiographs to CBCT was performed. The feasible range of X-ray projections achievable by a C-arm positioned around a da Vinci Si surgical robot, configured for robotic wedge resection, was determined using phantom models. Experiments were conducted on synthetic phantoms and animals imaged with an OEC 9600 and a Siemens Artis zeego, representing the spectrum of different C-arm systems currently available for clinical use. The image guidance workflow was feasible using either an optically tracked OEC 9600 or a Siemens Artis zeego C-arm, resulting in an angular difference of Δθ:∼ 30°. The two C-arm systems provided TRE mean ≤ 2.5 mm and TRE mean ≤ 2.0 mm, respectively (i.e., comparable to standard clinical intraoperative navigation systems). C-arm 3D localization from dual 2D-3D registered radiographs was feasible and applicable for intraoperative image guidance during da Vinci robotic thoracic interventions using the proposed workflow. Tissue deformation and in vivo experiments are required before clinical evaluation of this system.

  11. 78 FR 35575 - Black Lung Benefits Act: Standards for Chest Radiographs

    Science.gov (United States)

    2013-06-13

    ... toll-free number). Only comments of ten or fewer pages, including a Fax cover sheet and attachments, if... have different fee structures for film and digital radiographs. Instead, standard medical coding...

  12. Computing eye gaze metrics for the automatic assessment of radiographer performance during X-ray image interpretation.

    Science.gov (United States)

    McLaughlin, Laura; Bond, Raymond; Hughes, Ciara; McConnell, Jonathan; McFadden, Sonyia

    2017-09-01

    To investigate image interpretation performance by diagnostic radiography students, diagnostic radiographers and reporting radiographers by computing eye gaze metrics using eye tracking technology. Three groups of participants were studied during their interpretation of 8 digital radiographic images including the axial and appendicular skeleton, and chest (prevalence of normal images was 12.5%). A total of 464 image interpretations were collected. Participants consisted of 21 radiography students, 19 qualified radiographers and 18 qualified reporting radiographers who were further qualified to report on the musculoskeletal (MSK) system. Eye tracking data was collected using the Tobii X60 eye tracker and subsequently eye gaze metrics were computed. Voice recordings, confidence levels and diagnoses provided a clear demonstration of the image interpretation and the cognitive processes undertaken by each participant. A questionnaire afforded the participants an opportunity to offer information on their experience in image interpretation and their opinion on the eye tracking technology. Reporting radiographers demonstrated a 15% greater accuracy rate (p≤0.001), were more confident (p≤0.001) and took a mean of 2.4s longer to clinically decide on all features compared to students. Reporting radiographers also had a 15% greater accuracy rate (p≤0.001), were more confident (p≤0.001) and took longer to clinically decide on an image diagnosis (p=0.02) than radiographers. Reporting radiographers had a greater mean fixation duration (p=0.01), mean fixation count (p=0.04) and mean visit count (p=0.04) within the areas of pathology compared to students. Eye tracking patterns, presented within heat maps, were a good reflection of group expertise and search strategies. Eye gaze metrics such as time to first fixate, fixation count, fixation duration and visit count within the areas of pathology were indicative of the radiographer's competency. The accuracy and confidence of

  13. Potential usefulness of a video printer for producing secondary images from digitized chest radiographs

    Science.gov (United States)

    Nishikawa, Robert M.; MacMahon, Heber; Doi, Kunio; Bosworth, Eric

    1991-05-01

    Communication between radiologists and clinicians could be improved if a secondary image (copy of the original image) accompanied the radiologic report. In addition, the number of lost original radiographs could be decreased, since clinicians would have less need to borrow films. The secondary image should be simple and inexpensive to produce, while providing sufficient image quality for verification of the diagnosis. We are investigating the potential usefulness of a video printer for producing copies of radiographs, i.e. images printed on thermal paper. The video printer we examined (Seikosha model VP-3500) can provide 64 shades of gray. It is capable of recording images up to 1,280 pixels by 1,240 lines and can accept any raster-type video signal. The video printer was characterized in terms of its linearity, contrast, latitude, resolution, and noise properties. The quality of video-printer images was also evaluated in an observer study using portable chest radiographs. We found that observers could confirm up to 90 of the reported findings in the thorax using video- printer images, when the original radiographs were of high quality. The number of verified findings was diminished when high spatial resolution was required (e.g. detection of a subtle pneumothorax) or when a low-contrast finding was located in the mediastinal area or below the diaphragm (e.g. nasogastric tubes).

  14. Flash radiographic technique applied to fuel injector sprays

    International Nuclear Information System (INIS)

    Vantine, H.C.

    1977-01-01

    A flash radiographic technique, using 50 ns exposure times, was used to study the pattern and density distribution of a fuel injector spray. The experimental apparatus and method are described. An 85 kVp flash x-ray generator, designed and fabricated at the Lawrence Livermore Laboratory, is utilized. Radiographic images, recorded on standard x-ray films, are digitized and computer processed

  15. Multiline digital radiographic imager study with synchronization to detector gas ion drift

    International Nuclear Information System (INIS)

    Peyret, O.

    1985-01-01

    This direct digital radiographic imager is based on X-ray detection in high pressure rare gas ionization chamber. This linear multidetector, from which scanning radiography is realized, records many lines together. Spatial resolution performance in scanning direction are made sure by scanning synchronization with ion drift in detector. After a physical study and a potential evaluation of its performances on mock-up, a 128 cell prototype has been realized. The first images give validation and limits of such a radiographic process [fr

  16. A multicenter study analyzing the relationship of a standardized radiographic scoring system of adolescent idiopathic scoliosis and the Scoliosis Research Society outcomes instrument.

    Science.gov (United States)

    Wilson, Philip L; Newton, Peter O; Wenger, Dennis R; Haher, Thomas; Merola, Andrew; Lenke, Larry; Lowe, Thomas; Clements, David; Betz, Randy

    2002-09-15

    A multicenter study examining the association between radiographic and outcomes measures in adolescent idiopathic scoliosis. To evaluate the association between an objective radiographic scoring system and patient quality of life measures as determined by the Scoliosis Research Society outcomes instrument. Although surgical correction of scoliosis has been reported to be positively correlated with patient outcomes, studies to date have been unable to demonstrate an association between radiographic measures of deformity and outcomes measures in patients with adolescent idiopathic scoliosis. A standardized radiographic deformity scoring system and the Scoliosis Research Society outcome tool were used prospectively in seven scoliosis centers to collect data on patients with adolescent idiopathic scoliosis. A total of 354 data points for 265 patients consisting of those with nonoperative or preoperative curves >or=10 degrees, as well as those with surgically treated curves, were analyzed. Correlation analysis was performed to identify significant relationships between any of the radiographic measures, the Harms Study Group radiographic deformity scores (total, sagittal, coronal), and the seven Scoliosis Research Society outcome domains (Total Pain, General Self-Image, General Function, Activity, Postoperative Self-Image, Postoperative Function, and Satisfaction) as well as Scoliosis Research Society outcomes instrument total scores. Radiographic measures that were identified as significantly correlated with Scoliosis Research Society outcome scores were then entered into a stepwise regression analysis. The coronal measures of thoracic curve and lumbar curve magnitude were found to be significantly correlated with the Total Pain, General Self-Image, and total Scoliosis Research Society scores (P Society domain and total scores. No radiographic measures taken after surgery were significantly correlated with the postoperative domains of the Scoliosis Research Society

  17. Preliminary analysis of doses to evaluate the image quality in radiographic examinations in veterinary radiology

    International Nuclear Information System (INIS)

    Pinto, Ana Carolina B.C.F.; Dias, Mayara T.P.; Santos, Andrea C.; Melo, Camila S.; Furquim, Tania A.C.

    2009-01-01

    This work has as objective to promote the analysis of the radiological doses and quality of the image of the technical letter used for the accomplishment of thorax and coxal radiographic examination of animals of canine and feline species. The study was accomplished in the service of Diagnosis for Image in Veterinarian Hospital of Veterinary Medicine and Zootecnia College of University of Sao Paulo, in two conventional equipment. Initially, physical features of the animals and the technique used were collected for each one of the 188 radiographic examinations of thorax and 52 examinations of coxal. The animals were placed in different groups, according to their body weight. For each group, the averages for each feature were calculated: thickness of the radiographed region, tension, electric current, time of exhibition, current product electric-time, size of the used film, presence or absence of bucky and feature of focus (narrow or thick). On the basis of the averages of group M (of lesser weights that 5kg for cats and between 10,1kg and 20kg for dogs), was executed a physical analysis of the current technical letter, using the equipment: ionization chamber (to determinate the value of kerma in air), simulator objects (representative of the thickness of the animal) and three dispositive standards of test that evaluate space resolution, resolution in low contrast and contrast-detail. The obtained images were analyzed and compared for a physicist and a radiologist medical veterinary. The results had shown that the examinations supply dose considered high for techniques used mainly for coxal. The equipment A, although to supply higher doses, presents the better images for the majority of the projections. However, the study indicates that there are not exactly reference levels, but these examinations must pass for improvement of quality of image (author)

  18. Reconstruction of pseudo three-dimensional dental image from dental panoramic radiograph and tooth surface shape

    International Nuclear Information System (INIS)

    Imura, Masataka; Kuroda, Yoshihiro; Oshiro, Osamu; Kuroda, Tomohiro; Kagiyama, Yoshiyuki; Yagi, Masakazu; Takada, Kenji; Azuma, Hiroko

    2010-01-01

    Three-dimensional volume data set is useful for diagnosis in dental treatments. However, to obtain three-dimensional images of a dental arch in general dental clinics is difficult. In this paper, we propose a method to reconstruct pseudo three-dimensional dental images from a dental panoramic radiograph and a tooth surface shape which can be obtained from three dimensional shape measurement of a dental impression. The proposed method finds an appropriate curved surface on which the dental panoramic radiograph is mapped by comparing a virtual panoramic image made from a tooth surface shape to a real panoramic radiograph. The developed pseudo three-dimensional dental images give clear impression of patient's dental condition. (author)

  19. Visualization of postoperative anterior cruciate ligament reconstruction bone tunnels: Reliability of standard radiographs, CT scans, and 3D virtual reality images

    NARCIS (Netherlands)

    D.E. Meuffels (Duncan); J.W. Potters (Jan Willem); A.H.J. Koning (Anton); C.H. Brown Jr Jr. (Charles); J.A.N. Verhaar (Jan); M. Reijman (Max)

    2011-01-01

    textabstractBackground and purpose: Non-anatomic bone tunnel placement is the most common cause of a failed ACL reconstruction. Accurate and reproducible methods to visualize and document bone tunnel placement are therefore important. We evaluated the reliability of standard radiographs, CT scans,

  20. Reliability of linear distance measurement for dental implant length with standardized periapical radiographs

    International Nuclear Information System (INIS)

    Wakoh, Mamoru; Harada, Takuya; Otonari, Takamichi

    2006-01-01

    The purpose of this study was to investigate the accuracy of distance measurements of implant length based on periapical radiographs compared with that of other modalities. We carried out an experimental trial to compare precision in distance measurement. Dental implant fixtures were buried in the canine and first molar regions. These were then subjected to periapical (PE) radiography, panoramic (PA) radiography conventional (CV) and medical computed (CT) tomography. The length of the implant fixture on each film was measured by nine observers and degree of precision was statistically analyzed. The precision of both PE radiographs and CT tomograms was closest at the highest level. Standardized PE radiography, in particular, was superior to CT tomography in the first molar region. This suggests that standardized PE radiographs should be utilized as a reliable modality for longitudinal and linear distance measurement, depending on implant length at local implantation site. (author)

  1. Improvement of density resolution in short-pulse hard x-ray radiographic imaging using detector stacks

    Energy Technology Data Exchange (ETDEWEB)

    Borm, B.; Gärtner, F.; Khaghani, D. [GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt (Germany); Johann Wolfgang Goethe-Universität, Frankfurt am Main (Germany); Neumayer, P. [GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt (Germany)

    2016-09-15

    We demonstrate that stacking several imaging plates (IPs) constitutes an easy method to increase hard x-ray detection efficiency. Used to record x-ray radiographic images produced by an intense-laser driven hard x-ray backlighter source, the IP stacks resulted in a significant improvement of the radiograph density resolution. We attribute this to the higher quantum efficiency of the combined detectors, leading to a reduced photon noise. Electron-photon transport simulations of the interaction processes in the detector reproduce the observed contrast improvement. Increasing the detection efficiency to enhance radiographic imaging capabilities is equally effective as increasing the x-ray source yield, e.g., by a larger drive laser energy.

  2. Temporal subtraction of dual-energy chest radiographs

    International Nuclear Information System (INIS)

    Armato, Samuel G. III; Doshi, Devang J.; Engelmann, Roger; Caligiuri, Philip; MacMahon, Heber

    2006-01-01

    Temporal subtraction and dual-energy imaging are two enhanced radiography techniques that are receiving increased attention in chest radiography. Temporal subtraction is an image processing technique that facilitates the visualization of pathologic change across serial chest radiographic images acquired from the same patient; dual-energy imaging exploits the differential relative attenuation of x-ray photons exhibited by soft-tissue and bony structures at different x-ray energies to generate a pair of images that accentuate those structures. Although temporal subtraction images provide a powerful mechanism for enhancing visualization of subtle change, misregistration artifacts in these images can mimic or obscure abnormalities. The purpose of this study was to evaluate whether dual-energy imaging could improve the quality of temporal subtraction images. Temporal subtraction images were generated from 100 pairs of temporally sequential standard radiographic chest images and from the corresponding 100 pairs of dual-energy, soft-tissue radiographic images. The registration accuracy demonstrated in the resulting temporal subtraction images was evaluated subjectively by two radiologists. The registration accuracy of the soft-tissue-based temporal subtraction images was rated superior to that of the conventional temporal subtraction images. Registration accuracy also was evaluated objectively through an automated method, which achieved an area-under-the-ROC-curve value of 0.92 in the distinction between temporal subtraction images that demonstrated clinically acceptable and clinically unacceptable registration accuracy. By combining dual-energy soft-tissue images with temporal subtraction, misregistration artifacts can be reduced and superior image quality can be obtained

  3. Beyond image interpretation: Capturing the impact of radiographer advanced practice through activity diaries

    International Nuclear Information System (INIS)

    Snaith, B.; Milner, R.C.; Harris, M.A.

    2016-01-01

    Background: There is limited evidence of the impact of radiographers working in advanced roles beyond task substitution. This study reviews the contribution of advanced (and consultant) practitioner radiographers to service delivery whilst reporting radiographs and demonstrates the impact this has on patients and staff, both internal and external to the imaging department. Method: The study was a prospective exploratory study using activity diaries to allow interval sampling when individuals were rostered to report. Data was coded using a compiled list of activities and recorded in 15-min intervals over the period of one week. Thirteen radiographers who independently report radiographs participated across 6 locations in a busy multisite English National Health Service (NHS) Trust. Results: Radiographers reported the majority of the examinations during the study period (n = 4512/5671; 79.6%). The total number of coded activities recorded over the study period was 1527, equating to 380.5 relative hours. The majority of available time was spent reporting, including dictating and verifying the reports of colleagues or trainees, although 69.5% of reporting time was interrupted. Based upon the hours of reporting there was an average of 19.3 reports (patient episodes) produced per hour. Direct patient care tasks and support for staff in decision making were regularly documented. Supplementary tasks included administrative activity, amendments to rotas, preparing presentations and documenting incidents identified during reporting. Conclusion: This study has demonstrated the breadth and complexity of the activities performed by advanced practice radiographers. The findings confirm their role in supporting service delivery beyond image interpretation. - Highlights: • Radiographers can make a significant contribution to reporting workloads. • The range of activities undertaken when reporting is complex and varied. • Reporting radiographers impact on staff, patients

  4. 21 CFR 1020.31 - Radiographic equipment.

    Science.gov (United States)

    2010-04-01

    ...) RADIOLOGICAL HEALTH PERFORMANCE STANDARDS FOR IONIZING RADIATION EMITTING PRODUCTS § 1020.31 Radiographic... and time, a preset number of pulses, or a preset radiation exposure to the image receptor. (i) Except... exposure of greater than one-half second. Except during panoramic dental radiography, termination of...

  5. SU-E-I-94: Automated Image Quality Assessment of Radiographic Systems Using An Anthropomorphic Phantom

    International Nuclear Information System (INIS)

    Wells, J; Wilson, J; Zhang, Y; Samei, E; Ravin, Carl E.

    2014-01-01

    Purpose: In a large, academic medical center, consistent radiographic imaging performance is difficult to routinely monitor and maintain, especially for a fleet consisting of multiple vendors, models, software versions, and numerous imaging protocols. Thus, an automated image quality control methodology has been implemented using routine image quality assessment with a physical, stylized anthropomorphic chest phantom. Methods: The “Duke” Phantom (Digital Phantom 07-646, Supertech, Elkhart, IN) was imaged twice on each of 13 radiographic units from a variety of vendors at 13 primary care clinics. The first acquisition used the clinical PA chest protocol to acquire the post-processed “FOR PRESENTATION” image. The second image was acquired without an antiscatter grid followed by collection of the “FOR PROCESSING” image. Manual CNR measurements were made from the largest and thickest contrast-detail inserts in the lung, heart, and abdominal regions of the phantom in each image. An automated image registration algorithm was used to estimate the CNR of the same insert using similar ROIs. Automated measurements were then compared to the manual measurements. Results: Automatic and manual CNR measurements obtained from “FOR PRESENTATION” images had average percent differences of 0.42%±5.18%, −3.44%±4.85%, and 1.04%±3.15% in the lung, heart, and abdominal regions, respectively; measurements obtained from “FOR PROCESSING” images had average percent differences of -0.63%±6.66%, −0.97%±3.92%, and −0.53%±4.18%, respectively. The maximum absolute difference in CNR was 15.78%, 10.89%, and 8.73% in the respective regions. In addition to CNR assessment of the largest and thickest contrast-detail inserts, the automated method also provided CNR estimates for all 75 contrast-detail inserts in each phantom image. Conclusion: Automated analysis of a radiographic phantom has been shown to be a fast, robust, and objective means for assessing radiographic

  6. The radiographic anatomy of the normal ovine digit, the metacarpophalangeal and metatarsophalangeal joints.

    Science.gov (United States)

    Duncan, Jennifer S; Singer, Ellen R; Devaney, Jane; Oultram, Joanne W H; Walby, Anna J; Lester, Bridie R; Williams, Helen J

    2013-03-01

    The aim of this project was to develop a detailed, accessible set of reference images of the normal radiographic anatomy of the ovine digit up to and including the metacarpo/metatatarsophalangeal joints. The lower front and hind limbs of 5 Lleyn ewes were radiographed using portable radiography equipment, a digital image processer and standard projections. Twenty images, illustrating the normal radiographic anatomy of the limb were selected, labelled and presented along with a detailed description and corresponding images of the bony skeleton. These images are aimed to be of assistance to veterinary surgeons, veterinary students and veterinary researchers by enabling understanding of the normal anatomy of the ovine lower limb, and allowing comparison with the abnormal.

  7. Method and apparatus for improving the alignment of radiographic images

    International Nuclear Information System (INIS)

    Schuller, P.D.; Hatcher, D.C.; Caelli, T.M.; Eggert, F.M.; Yuzyk, J.

    1991-01-01

    This invention relates generally to the field of radiology, and has to do particularly with a method and apparatus for improving the alignment of radiographic images taken at different times of the same tissue structure, so that the images can be sequentially shown in aligned condition, whereby changes in the structure can be noted. (author). 10 figs

  8. Quality of radiograph

    International Nuclear Information System (INIS)

    Abdul Nassir Ibrahim; Azali Muhammad; Ab. Razak Hamzah; Abd. Aziz Mohamed; Mohamad Pauzi Ismail

    2008-01-01

    This chapter discussed on how to get a good radiograph. There are several factors that can make good radiograph such as density of radiograph, the contrast of radiograph, definition of radiograph, the present of artifact and backscattering. All of this factor will discuss detailed on each unit of chapter with some figure, picture to make the reader understand more when read this book. And at the end, the reader will introduce with penetrameter, one of device to determine the level of quality of the radiograph. There are two type of penetrameter like wire type or holes type. This standard must be followed by all the radiographer around the world to produce the good result that is standard and more reliable.

  9. Radiographic techniques adaptation for any conventional X-ray equipment

    International Nuclear Information System (INIS)

    Pina, Diana R.; Ghilardi Netto, Thomaz; Martinez, Alexandre S.; Duarte, Sergio B.; Trad, Clovis S.; Brochi, Marco Aurelio C.

    2001-01-01

    In order to obtain a better risk-benefice relation in diagnostic radiology it turns out to be essential the control and optimization of the radiographic techniques used to reduce the absorbed doses until its minimum, keeping or adjusting the diagnostic image at any X-ray equipment. The present work deals with the standardization of radiographic techniques of chest, skull and pelvis, which is more suitable for obtaining a safe diagnostic with smaller doses, for a standard patient, at any conventional X-ray equipment. (author)

  10. Semi-automated digital image analysis of patellofemoral joint space width from lateral knee radiographs

    Energy Technology Data Exchange (ETDEWEB)

    Grochowski, S.J. [Mayo Clinic, Department of Orthopedic Surgery, Rochester (United States); Amrami, K.K. [Mayo Clinic, Department of Radiology, Rochester (United States); Kaufman, K. [Mayo Clinic, Department of Orthopedic Surgery, Rochester (United States); Mayo Clinic/Foundation, Biomechanics Laboratory, Department of Orthopedic Surgery, Charlton North L-110L, Rochester (United States)

    2005-10-01

    To design a semi-automated program to measure minimum patellofemoral joint space width (JSW) using standing lateral view radiographs. Lateral patellofemoral knee radiographs were obtained from 35 asymptomatic subjects. The radiographs were analyzed to report both the repeatability of the image analysis program and the reproducibility of JSW measurements within a 2 week period. The results were also compared with manual measurements done by an experienced musculoskeletal radiologist. The image analysis program was shown to have an excellent coefficient of repeatability of 0.18 and 0.23 mm for intra- and inter-observer measurements respectively. The manual method measured a greater minimum JSW than the automated method. Reproducibility between days was comparable to other published results, but was less satisfactory for both manual and semi-automated measurements. The image analysis program had an inter-day coefficient of repeatability of 1.24 mm, which was lower than 1.66 mm for the manual method. A repeatable semi-automated method for measurement of the patellofemoral JSW from radiographs has been developed. The method is more accurate than manual measurements. However, the between-day reproducibility is higher than the intra-day reproducibility. Further investigation of the protocol for obtaining sequential lateral knee radiographs is needed in order to reduce the between-day variability. (orig.)

  11. Evaluation of computed tomography post-processing images in postoperative assessment of Lisfranc injuries compared with plain radiographs.

    Science.gov (United States)

    Li, Haobo; Chen, Yanxi; Qiang, Minfei; Zhang, Kun; Jiang, Yuchen; Zhang, Yijie; Jia, Xiaoyang

    2017-06-14

    The objective of this study is to evaluate the value of computed tomography (CT) post-processing images in postoperative assessment of Lisfranc injuries compared with plain radiographs. A total of 79 cases with closed Lisfranc injuries that were treated with conventional open reduction and internal fixation from January 2010 to June 2016 were analyzed. Postoperative assessment was performed by two independent orthopedic surgeons with both plain radiographs and CT post-processing images. Inter- and intra-observer agreement were analyzed by kappa statistics while the differences between the two postoperative imaging assessments were assessed using the χ 2 test (McNemar's test). Significance was assumed when p processing images was much higher than that of plain radiographs. Non-anatomic reduction was more easily identified in patients with injuries of Myerson classifications A, B1, B2, and C1 using CT post-processing images with overall groups (p processing images with overall groups (p processing images can be more reliable than plain radiographs in the postoperative assessment of reduction and implant placement for Lisfranc injuries.

  12. Sensitivity of radiographic features and specificity of scintigraphic imaging in hand osteoarthritis

    International Nuclear Information System (INIS)

    Buckland-Wright, J.C.; MacFarlane, D.G.; Lynch, J.A.

    1995-01-01

    We undertook to determine which of the radiographic features most reliably detected the presence and disease progression in osteoarthritis in the hand; and which of the radiographic features corresponded with the radionuclide bone scan images. 32 patients with osteoarthritis had X5 macroradiographs taken of their wrists and hands at 6 monthly intervals over an 18 month period. The high magnification and resolution of microfocal radiography permitted quantitative detection of the extent and change in joint space width, subchondral sclerosis, osteophytosis and juxtaarticular radiolucencies. 4-hour technetium 99 m methylene bisphophonate bone scans were taken at 0 and 12 months and the activity of the tracer uptake at each joint scored. The latter was compared with the radiographic features at each visit and the changes between visits analysed. In hand OA the most sensitive radiographic parameters for detecting disease were osteophytes, subchondral sclerosis and justaarticular radiolucencies, with radionuclide imaging demonstrating the increased activity in bone formation associated with the growth and remodelling of osteophytes. Changes in the number and size of osteophytes and joint space narrowing were the only reliable and sensitive parameters for assessing disease progression. We conclude that in osteoarthritis, the bony changes progress significantly before the occurrence of radiographically evident joint space narrowing indicative of cartilage thinning. (authors). 48 refs., 2 tabs., 11 figs

  13. Radiographic assessment of proximal caries: A comparison between film-based and dexis digital imaging systems

    Directory of Open Access Journals (Sweden)

    Anupama N Kalappanavar

    2011-01-01

    Full Text Available This study compared Kodak Ektaspeed film and Dexis digital imaging systems for their diagnostic accuracy in detection of proximal canes in 210 proximal surfaces from 105 extracted human teeth (20 premolars and 85 molars, 129 of which were carious. Ground teeth were evaluated histologically. The images were assessed by an observer. ANOVA revealed that groups differ in scoring patterns with f-value of 26.72 and p < 0.01. The mean caries score by histologic assessment was significantly (p < 0.01 more when compared with the scores obtained by conventional and Dexis digital radiographic methods. The mean score for conventional radiographic method was slightly more than Dexis digital radiographic method, but the difference was statistically insignificant (p < 0.05. Both the radiographic methods were less accurate in detecting proximal canes confined to enamel, but as the lesion depth was increased to dentin, the rate of caries detection increased dramatically. It was concluded that both conventional and Dexis digital radiographic methods under estimated canes depth when compared with histologic method. Lastly, conventional film radiographs and Dexis digital radiographs did not perform significantly different from each other in the detection of canes.

  14. Radiographic imaging of the canine intercondylar fossa

    International Nuclear Information System (INIS)

    Montgomery, R.D.; Fitch, R.B.; Hathcock, J.T.; LaPrade, R.F.; Wilson, M.E.; Garrett, P.D.

    1996-01-01

    The intercondylar fossa is believed to play an important role in the pathology of cranial cruciate ligament rupture and therefore has received considerable attention in the last decade. Accurate radiographic imaging of the intercondylar fossa requires that the central x-ray beam pass through the center of the intercondylar “tunnel”. The anatomy of the canine intercondylar fossa is similar to humans, however, the orientations of the intercondylar fossa's differ. Consequently, the positioning techniques described for humans are not appropriate for the dog. To pass through the center of the dog, intercondylar fossa, the central x-ray beam should be 12° (S.D. 1.7°) caudal from the femoral diaphysis in the sagittal plane and obliqued caudolateral to craniomedial 7° (S.D. 0.60°) (caudo78°proximo7° lateralcraniodistomedial oblique). Cross table positioning was used with the hip flexed and the radiograph cassette placed on the cranial surface of the stifle. However, superimposition of the tuber ischii and soft tissues caudal to the femur made 15° to 20° the best angle obtainable. There was not a significant difference (p = 0.17) in the notch width index between a 12° versus 20° angle of the central x-ray beam caudal to the femoral diaphysis, both with 7° of external rotation of the stifle. The notch width index of 0.252 obtained from radiographic measurements was not significantly different from measurements obtained grossly of 0.254 (n = 26; p = 0.69). Failure to oblique the central x-ray beam caused a significant (p = 0.0008) decrease in the apparent fossa width radiographically

  15. Correlation of bone quality in radiographic images with clinical bone quality classification

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyun Woo; Huh, Kyung Hoe; Kim, Jeong Hwa; Yi, Won Jin; Heo, Min Suk; Lee, Sam Sun; Choi, Soon Chul [Seoul National University, Seoul (Korea, Republic of); Park, Kwan Soo [Inje University, Seoul (Korea, Republic of)

    2006-03-15

    To investigate the validity of digital image processing on panoramic radiographs in estimating bone quality before endosseous dental implant installation by correlating bone quality in radiographic images with clinical bone quality classification. An experienced surgeon assessed and classified bone quality for implant sites with tactile sensation at the time of implant placement. Including fractal dimension eighteen morphologic features of trabecular pattern were examined in each anatomical sites on panoramic radiographs. Finally bone quality of 67 implant sites were evaluated in 42 patients. Pearson correlation analysis showed that three morphologic parameters had weak linear negative correlation with clinical bone quality classification showing correlation coefficients of -0.276, -0.280, and -0.289, respectively (p<0.05). And other three morphologic parameters had obvious linear negative correlation with clinical bone quality classification showing correlation coefficients of -0.346, -0.488, and -0.343 respectively (p<0.05). Fractal dimension also had a linear correlating with clinical bone quality classification with correlation coefficients -0.506 significantly (P<0.05). This study suggests that fractal and morphometric analysis using digital panoramic radiographs can be used to evaluate bone quality for implant recipient sites.

  16. Australian diagnostic radiographers' attitudes and perceptions of imaging obese patients: A study of self, peers and students

    International Nuclear Information System (INIS)

    Aweidah, L.; Robinson, J.; Cumming, S.; Lewis, S.

    2016-01-01

    Introduction and Objective: Imaging obese patients poses a number of challenges for diagnostic radiographers through positioning, radiation exposure, communication and care. Furthermore, the increasing prevalence of obesity in Australian society ensures these imaging challenges are more frequent however little is known about this area. This study aims to explore the attitudes and perceptions of diagnostic radiographers toward imaging obese patients through a mixed methods study. Methods: Ethics approval was granted to interview and survey diagnostic radiographers about their attitudes and perceptions of imaging obese patients. Twelve diagnostic radiographers who are designated clinical educators (DR CEs) took part in a 30–45 min semi-structured interview as well as a 20 min computer-based Weight Implicit Association Test (Weight-IAT) and self-report questionnaire of explicit attitudes. An additional 25 experienced Diagnostic Radiographers who were associate supervisors completed the Weight-IAT/explicit questionnaire only. Results: Thematic analysis of the interviews revealed that DR CEs adopted an image-focussed or patient-focussed approach to obese patients. Key themes with a negative bias included blame, tolerance and insecurity of skill. Positively associated key themes were empathy and experience in radiography. The sample overall showed a significant negative implicit weight bias (P = 0.016) as measured by the Weight-IAT and there was no evidence of negative explicit attitudes. Conclusion: Australian diagnostic radiographers in this study exhibited significant negative implicit weight bias, with interview results highlighting attitudes of blame and frustration towards obese patients. DR CEs were more likely to be focussed on image acquisition rather than patient considerations, with fewer responses related to empathy and equity. - Highlights: • Mixed-methods study combining qualitative interviews and implicit–explicit bias towards imaging obese

  17. Inter-observer variation in masked and unmasked images for quality evaluation of clinical radiographs

    International Nuclear Information System (INIS)

    Tingberg, A.; Eriksson, F.; Medin, J.; Besjakov, J.; Baarth, M.; Haakansson, M.; Sandborg, M.; Almen, A.; Lanhede, B.; Alm-Carlsson, G.; Mattsson, S.; Maansson, L. G.

    2005-01-01

    Purpose: To investigate the influence of masking on the inter-observer variation in image quality evaluation of clinical radiographs of chest and lumbar spine. Background: Inter-observer variation is a big problem in image quality evaluation since this variation is often much bigger than the variation in image quality between, for example, two radiographic systems. In this study, we have evaluated the effect of masking on the inter-observer variation. The idea of the masking was to force every observer to view exactly the same part of the image and to avoid the effect of the overall 'first impression' of the image. A discussion with a group of European expert radiologists before the study indicated that masking might be a good way to reduce the inter-observer variation. Methods: Five chest and five lumbar spine radiographs were collected together with detailed information regarding exposure conditions. The radiographs were digitised with a high-performance scanner and five different manipulations were performed, simulating five different exposure conditions. The contrast, noise and spatial resolution were manipulated by this method. The images were printed onto the film and the individual masks were produced for each film, showing only the parts of the images that were necessary for the image quality evaluation. The quality of the images was evaluated on ordinary viewing boxes by a large group of experienced radiologists. The images were examined with and without the masks with a set of image criteria (if fulfilled, 1 point; and not fulfilled, 0 point), and the mean score was calculated for each simulated exposure condition. Results: The results of this study indicate that - contrary to what was supposed - the inter-observer variation increased when the images were masked. In some cases, especially for chest, this increase was statistically significant. Conclusions: Based on the results of this study, image masking in studies of fulfilment of image criteria cannot

  18. The effect of liquid media on x-ray radiographic sensitivity

    International Nuclear Information System (INIS)

    Abdul Razak bin Daud; Ahmad Suhaimi bin Abdullah; Azali bin Muhamad

    1991-01-01

    The effect of liquid media i.e. tap water, seawater and crude oil on X-Rays radiographic sensitivity for 120, 160, 200 kV X-Rays was investigated. Stainless steel plates were used as specimens. Image quality indicators were German standard DIN 54109 - wire type and penetrameter ASME-SE142. Result obtained shows that radiographic sensitivity percents obtained in the liquid media using wire type image quality indicator and penetrameter are lessened to about 20-25% and 40-44% respectively with respect to radiographic sensitivity obtained in air. Optimum thickness of specimen for appropriate X-ray energies where sensitivity is best does not vary in air, tap water, seawater or crude oil

  19. Benchmarking the performance of fixed-image receptor digital radiographic systems part 1: a novel method for image quality analysis.

    Science.gov (United States)

    Lee, Kam L; Ireland, Timothy A; Bernardo, Michael

    2016-06-01

    This is the first part of a two-part study in benchmarking the performance of fixed digital radiographic general X-ray systems. This paper concentrates on reporting findings related to quantitative analysis techniques used to establish comparative image quality metrics. A systematic technical comparison of the evaluated systems is presented in part two of this study. A novel quantitative image quality analysis method is presented with technical considerations addressed for peer review. The novel method was applied to seven general radiographic systems with four different makes of radiographic image receptor (12 image receptors in total). For the System Modulation Transfer Function (sMTF), the use of grid was found to reduce veiling glare and decrease roll-off. The major contributor in sMTF degradation was found to be focal spot blurring. For the System Normalised Noise Power Spectrum (sNNPS), it was found that all systems examined had similar sNNPS responses. A mathematical model is presented to explain how the use of stationary grid may cause a difference between horizontal and vertical sNNPS responses.

  20. Can skeletal image reporting be taught online: Perspectives of experienced reporting radiographers?

    International Nuclear Information System (INIS)

    Leishman, Lesley

    2013-01-01

    Background: Image interpretation relies upon expert clinical skill and comprehensive knowledge and understanding of the theories and concepts that underpin clinical practices. Traditionally, radiographer reporting education has been delivered using a blend of classroom based learning combined with workplace clinical practice. The direct and indirect costs of staff development and maintenance of the service has seen the incorporation of e-learning into courses in other health professions. Yet, despite its proven success, in the UK radiography has been resistant to progression into e-learning for reporting. This study aims to explore the perceptions of reporting radiographers to interactive online delivery of skeletal image reporting education. Method: Invitations to participate in the study were sent to 80 radiology departments in the UK. Reporting radiographers were asked to complete an online questionnaire to detail their reporting education experiences and to consider whether online delivery was a viable option. Results: A total of 86 radiographers participated in the study. They could see potential benefits of online delivery but agreed it would only be suitable for delivery of theoretical subjects, and that development of practical/clinical skills required interaction with experts in the field to enhance learning. Conclusion: Image reporting education is not suitable for entirely online delivery, and a blended learning solution, where online classroom based learning is combined with work based learning is more appropriate as it allows for interaction with experts in the field of reporting to facilitate the development of reporting skills enhance the overall learning experience

  1. High-Throughput Classification of Radiographs Using Deep Convolutional Neural Networks.

    Science.gov (United States)

    Rajkomar, Alvin; Lingam, Sneha; Taylor, Andrew G; Blum, Michael; Mongan, John

    2017-02-01

    The study aimed to determine if computer vision techniques rooted in deep learning can use a small set of radiographs to perform clinically relevant image classification with high fidelity. One thousand eight hundred eighty-five chest radiographs on 909 patients obtained between January 2013 and July 2015 at our institution were retrieved and anonymized. The source images were manually annotated as frontal or lateral and randomly divided into training, validation, and test sets. Training and validation sets were augmented to over 150,000 images using standard image manipulations. We then pre-trained a series of deep convolutional networks based on the open-source GoogLeNet with various transformations of the open-source ImageNet (non-radiology) images. These trained networks were then fine-tuned using the original and augmented radiology images. The model with highest validation accuracy was applied to our institutional test set and a publicly available set. Accuracy was assessed by using the Youden Index to set a binary cutoff for frontal or lateral classification. This retrospective study was IRB approved prior to initiation. A network pre-trained on 1.2 million greyscale ImageNet images and fine-tuned on augmented radiographs was chosen. The binary classification method correctly classified 100 % (95 % CI 99.73-100 %) of both our test set and the publicly available images. Classification was rapid, at 38 images per second. A deep convolutional neural network created using non-radiological images, and an augmented set of radiographs is effective in highly accurate classification of chest radiograph view type and is a feasible, rapid method for high-throughput annotation.

  2. A quantitative performance evaluation of the EM algorithm applied to radiographic images

    International Nuclear Information System (INIS)

    Brailean, J.C.; Sullivan, B.J.; Giger, M.L.; Chen, C.T.

    1991-01-01

    In this paper, the authors quantitatively evaluate the performance of the Expectation Maximization (EM) algorithm as a restoration technique for radiographic images. The perceived signal-to-noise ratio (SNR), of simple radiographic patterns processed by the EM algorithm are calculated on the basis of a statistical decision theory model that includes both the observer's visual response function and a noise component internal to the eye-brain system. The relative SNR (ratio of the processed SNR to the original SNR) is calculated and used as a metric to quantitatively compare the effects of the EM algorithm to two popular image enhancement techniques: contrast enhancement (windowing) and unsharp mask filtering

  3. An investigation of Saudi Arabian MR radiographers' knowledge and confidence in relation to MR image-quality-related errors

    International Nuclear Information System (INIS)

    Alsharif, W.; Davis, M.; McGee, A.; Rainford, L.

    2017-01-01

    Objective: To investigate MR radiographers' current knowledge base and confidence level in relation to quality-related errors within MR images. Method: Thirty-five MR radiographers within 16 MRI departments in the Kingdom of Saudi Arabia (KSA) independently reviewed a prepared set of 25 MR images, naming the error, specifying the error-correction strategy, scoring how confident they were in recognising this error and suggesting a correction strategy by using a scale of 1–100. The datasets were obtained from MRI departments in the KSA to represent the range of images which depicted excellent, acceptable and poor image quality. Results: The findings demonstrated a low level of radiographer knowledge in identifying the type of quality errors and when suggesting an appropriate strategy to rectify those errors. The findings show that only (n = 7) 20% of the radiographers could correctly name what the quality errors were in 70% of the dataset, and none of the radiographers correctly specified the error-correction strategy in more than 68% of the MR datasets. The confidence level of radiography participants in their ability to state the type of image quality errors was significantly different (p < 0.001) for who work in different hospital types. Conclusion: The findings of this study suggest there is a need to establish a national association for MR radiographers to monitor training and the development of postgraduate MRI education in Saudi Arabia to improve the current status of the MR radiographers' knowledge and direct high quality service delivery. - Highlights: • MR radiographers recognised the existence of the image quality related errors. • A few MR radiographers were able to correctly identify which image quality errors were being shown. • None of MR radiographers were able to correctly specify error-correction strategy of the image quality errors. • A low level of knowledge was demonstrated in identifying and rectify image quality errors.

  4. Cine MR imaging before and after realignment surgery for patellar maltracking - comparison with axial radiographs

    Energy Technology Data Exchange (ETDEWEB)

    Brossmann, J. [Klinik fuer Radiologische Diagnostik der Univ. Kiel (Germany); Muhle, C. [Klinik fuer Radiologische Diagnostik der Univ. Kiel (Germany); Buell, C.C. [Rheumaklinik, Bad Bramstedt (Germany); Zieplies, J. [Lubinus Klinik, Kiel (Germany); Melchert, U.H. [Klinik fuer Radiologische Diagnostik der Univ. Kiel (Germany); Brinkmann, G. [Klinik fuer Radiologische Diagnostik der Univ. Kiel (Germany); Schroeder, C. [Klinik fuer Radiologische Diagnostik der Univ. Kiel (Germany); Heller, M. [Klinik fuer Radiologische Diagnostik der Univ. Kiel (Germany)

    1995-04-01

    Comparison of motion-triggered cine magnetic resonance (MR) imaging and conventional radiographs for the assessment of operative results of patellar realignment. Fifteen patients with recurrent patellar dislocation or patellar subluxation were evaluated with conventional axial radiographs before and after realignment surgery by measuring the congruence angle (CA), lateral patellofemoral angle (LPFA), and lateral displacement (d). In eight patients the patellofemoral joint was additionally evaluated pre- and postoperatively with motion-triggered cine MR imaging by determining the bisect offset (BSO), lateral patellar displacement (LPD), and patellar tilt angle (PTA). Significant differences between the pre- and postoperative measurements were found for all MR imaging parameters (BSO, LPD, PTA: p<0.01) but not for the conventional X-ray parameters (CA: p=0.70, LPFA: p=0.56; d: p=0.04). Motion-triggered cine MR imaging was superior to conventional tangential radiographs for assessing the effectiveness of patellar realignment surgery. (orig.)

  5. Cine MR imaging before and after realignment surgery for patellar maltracking - comparison with axial radiographs

    International Nuclear Information System (INIS)

    Brossmann, J.; Muhle, C.; Buell, C.C.; Zieplies, J.; Melchert, U.H.; Brinkmann, G.; Schroeder, C.; Heller, M.

    1995-01-01

    Comparison of motion-triggered cine magnetic resonance (MR) imaging and conventional radiographs for the assessment of operative results of patellar realignment. Fifteen patients with recurrent patellar dislocation or patellar subluxation were evaluated with conventional axial radiographs before and after realignment surgery by measuring the congruence angle (CA), lateral patellofemoral angle (LPFA), and lateral displacement (d). In eight patients the patellofemoral joint was additionally evaluated pre- and postoperatively with motion-triggered cine MR imaging by determining the bisect offset (BSO), lateral patellar displacement (LPD), and patellar tilt angle (PTA). Significant differences between the pre- and postoperative measurements were found for all MR imaging parameters (BSO, LPD, PTA: p<0.01) but not for the conventional X-ray parameters (CA: p=0.70, LPFA: p=0.56; d: p=0.04). Motion-triggered cine MR imaging was superior to conventional tangential radiographs for assessing the effectiveness of patellar realignment surgery. (orig.)

  6. Standard practice for digital imaging and communication in nondestructive evaluation (DICONDE) for digital radiographic (DR) test methods

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 This practice facilitates the interoperability of digital X-ray imaging equipment by specifying image data transfer and archival methods in commonly accepted terms. This document is intended to be used in conjunction with Practice E2339 on Digital Imaging and Communication in Nondestructive Evaluation (DICONDE). Practice E2339 defines an industrial adaptation of the NEMA Standards Publication titled Digital Imaging and Communications in Medicine (DICOM, see http://medical.nema.org), an international standard for image data acquisition, review, storage and archival storage. The goal of Practice E2339, commonly referred to as DICONDE, is to provide a standard that facilitates the display and analysis of NDE results on any system conforming to the DICONDE standard. Toward that end, Practice E2339 provides a data dictionary and a set of information modules that are applicable to all NDE modalities. This practice supplements Practice E2339 by providing information object definitions, information modules and a ...

  7. Value of radiographic examination of the knee joint for the orthopedic surgeon

    International Nuclear Information System (INIS)

    Pietsch, M.; Hofmann, S.

    2006-01-01

    Extended radiographic examinations offer excellent options for diagnosis and strategy for treatment of the knee joint. The whole-leg radiograph is indispensable in measuring alignment for osteotomy or total knee arthroplasty (TKA). Fluoroscopically assisted varus-valgus stress radiographs provide the possibility for verifying mechanical function of the implanted knee prosthesis. Ultrasound examinations have been widely replaced by magnetic resonance imaging (MRI). MRI is the golden standard to examine intra-articular structures of the knee (meniscus, ligaments, cartilage) and surrounding soft tissue. For evaluating femoral and tibial torsion and determining axial rotation of TKA, computed tomography (CT) is best qualified. Imaging of the patellofemoral joint (patella instability) is difficult; CT scans in combination with true lateral radiographs seem to be helpful. (orig.) [de

  8. Standard digital reference images for inspection of aluminum castings

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2005-01-01

    1.1 These digital reference images illustrate the types and degrees of discontinuities that may be found in aluminum-alloy castings. The castings illustrated are in thicknesses of 1/ 4 in. [6.35 mm] and 3/4 in. [19.1mm]. 1.2 All areas of this standard may be open to agreement between the cognizant engineering organization and the supplier, or specific direction from the cognizant engineering organization. These items should be addressed in the purchase order or the contract. 1.3 The values stated in inch-pound units are to be regarded as standard. 1.4 These digital reference images are not intended to illustrate the types and degrees of discontinuities found in aluminum-alloy castings when performing film radiography. If performing film radiography of aluminum-alloy castings, refer to Reference Radiographs E 155. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and he...

  9. Fast radiographic systems

    International Nuclear Information System (INIS)

    Domanus, J.C.

    1984-08-01

    Industrial radiography can be performed with shorter exposure times, when instead of X-ray film with lead intensifying screens the radiographic paper with fluorescent screen is used. With paper radiography one can obtain lower material, equipment, and labor costs, shorter exposure and processing times, and easier radiation protection. The speed of the radiographic inspection can also be increased by the use of fluorometallic intensifying screens together with a special brand of X-ray film. Before accepting either of the two fast radiographic systems one must be sure that they can produce radiographs of adequate image quality. Therefore an investigation was performed on that subject using ISO wire IQI's and ASTM penetrameters. The radiographic image quality was tested for aluminium and steel up to 30 mm thick using various brands of radiographic paper and X-ray film with fluorometallic screens and comparing them with fast X-ray films with lead screens. Both systems give satisfactory results. (author)

  10. Implementation of quality assurance program of the radiographic image at public hospitals of Aracaju-SE, Brazil

    International Nuclear Information System (INIS)

    Ferreira, C.C.; Souza, S.O.

    2007-01-01

    The initial conditions of the darkroom and X rays films processing of two public hospitals, called A and B hospitals, at Aracaju-SE city had been evaluated. This evaluation was performed to define the actions for an Quality Assurance Program (QAP) aiming to improve the radiographic images quality and costs reduction for both hospitals. The evaluation of the initial conditions of the hospital B showed that a large reduction in the film rejection index and in its radiographic image artifacts can be obtained after the QAP deeds be accomplished. In the A hospital, the actions that have been deployed by the AQP resulted in a reduction of about 50% of the costs associated to chemical products consumption and improved the radiographic image quality. It was demonstrated by a decrease in the radiographs rejection index of 7 % to 5%. The results also revealed that the presence of a medical physicist able to follow the QAP is essential, because, without him, the program, in general, is neglected. (author)

  11. Evolution of Entrance Surface Doses and Image Quality in Pediatric Chest Radiographs

    International Nuclear Information System (INIS)

    Campello, A.C.; Marques, D.T.; Medeiros, C.B.; Carvalho, P.P.; Khoury, H.J.; Azevedo, A.C.P.

    2006-01-01

    This work presents the results of a survey about image quality, radiographic techniques and patient doses in a large public hospital located in the city of Recife, Brazil. It was detected that the quality criteria are not fully reached and represent 70% of the agreement with recommendations from the European Community. Concerning the radiographic techniques the kV is in accordance with international recommendations in 90% if the examinations while the exposure time is 72%. The results also show that the dose values change in the range from 0.020 to 0.250 mGy. The variability is mainly caused by the disparity on the radiographic techniques employed in the examinations as well as by the radiographer's expertise. It could be concluded that the ALARA principle is not being applied in the hospital, which becomes a concern in terms of public health. (author)

  12. An evaluation of radiographer performed and interpreted barium swallows and meals

    International Nuclear Information System (INIS)

    Judson, E.E.; Nightingale, J.M.

    2009-01-01

    Aim: To determine whether radiographers are able to perform and interpret barium swallows and meals (BSM) to an acceptable standard. Materials and methods: A retrospective audit was performed of all radiographer-managed BSMs over a 4-year period in an acute hospital. Descriptive statistics were used to analyse patient demographics, radiation doses, referral sources, and imaging findings. Radiographer reports were compared with radiologist reports assumed to be the reference standard, and correlated with patient outcomes via electronic record searches and case note scrutiny. Reporting accuracy, sensitivity, and specificity were calculated. Results: Three radiographers performed a total of 962 BSMs in the 4-year audit period, including a varied and complex case-mix. Only 13 (0.01%) cases were abandoned due to technical reasons, with all other examinations of diagnostic quality. Although radiation dose levels were initially variable, following the installation of modern fluoroscopy equipment they remained comfortably within the national and regional diagnostic reference levels. Consultant radiologists verified the majority of the radiographer reports, with the most experienced radiographer independently reporting 230 cases (24%). Follow-up of patient outcome was possible in 935 cases. The overall radiographer accuracy based on the 935 cases was 98.9%, sensitivity 98%, and specificity 98.9%. Conclusions: Appropriately trained radiographers are able to perform and interpret BSM examinations to a very high standard.

  13. Reproducibility of lateral cephalometric landmarks on conventional radiographs and spatial frequency-processed digital images

    International Nuclear Information System (INIS)

    Shin, Jeong Won; Heo, Min Suk; Lee, Sam Sun; Choi, Hyun Bae; Choi, Soon Chul; Choi, Hang Moon

    2002-01-01

    Computed radiography (CR) has been used in cephalometric radiography and many studies have been carried out to improve image quality using various digital enhancement and filtering techniques. During CR image acquisition, the frequency rank and type affect to the image quality. The aim of this study was to compare the diagnostic quality of conventional cephalometric radiographs to those of computed radiography. The diagnostic quality of conventional cephalometric radiographs (M0) and their digital image counterparts were compared, and at the same time, six modalities (M1-M6) of spatial frequency-processed digital images were compared by evaluating the reproducibility of 23 cephalometric landmark locations. Reproducibility was defined as an observer's deviation (in mm) from the mean between all observers. In comparison with the conventional cephalometric radiograph (M0), M1 showed statistically significant differences in 8 locations, M2 in 9, M3 12, M4 in 7, M5 in 12, and M6 showed significant differences in 14 of 23 landmark locations (p<0.05). The number of reproducible landmarks that each modality possesses were 7 in M6, 6 in M5, 5 in M3, 4 in M4, 3 in M2, 2 in M1, and 1 location in M0. The image modality that observers selected as having the best image quality was M5.

  14. Diagnostic agreement between panoramic radiographs and color doppler images of carotid atheroma

    Directory of Open Access Journals (Sweden)

    Claudia Maria Romano-Sousa

    2009-02-01

    Full Text Available The aim of this study was to investigate the agreement between diagnoses of calcified atheroma seen on panoramic radiographs and color Doppler images. Our interest stems from the fact that panoramic images can show the presence of atheroma regardless of the level of obstruction detected by color Doppler images. Panoramic and color Doppler images of 16 patients obtained from the archives of the Health Department of the city of Valença, RJ, Brazil, were analyzed in this study. Both sides of each patient were observed on the images, with a total of 32 analyzed cervical regions. The level of agreement between diagnoses was analyzed using the Kappa statistics. There was a high level of agreement, with a Kappa value of 0.78. In conclusion, panoramic radiographs can help detecting calcifications in the cervical region of patients susceptible to vascular diseases predisposing to myocardial infarction and cerebrovascular accidents. If properly trained and informed, dentists can refer their patients to a physician for a cardiovascular evaluation in order to receive proper and timely medical treatment.

  15. A Reduction in Radiographic Exposure and Image Quality in Film ...

    African Journals Online (AJOL)

    Purpose: To develop a protocol for the optimization of diagnostic chest radiography examination, the effect of radiographic exposure reduction on image quality is investigated. Procedure: Fourty-eight adult patients presenting for posterior-anterior (PA) chest radiography in a tertiary health care centre were categorized into 3 ...

  16. Comparison of Two Methods for Evaluation of the Image Quality of Lumbar Spine Radiographs

    International Nuclear Information System (INIS)

    Tingberg, A.; Herrmann, C.; Lanhede, B.; Almn, A.; Besjakov, J.; Mattsson, S.; Sund, P.; Kheddache, S.; Maasson, L.G.

    2000-01-01

    Two methods for visual evaluation of image quality of clinical radiographs have been compared. In visual grading analysis (VGA) specified anatomical structures in an image are visually compared with the same structures in a reference image, and in a free-response forced error (FFE) experiment - an extension of conventional ROC (receiver operating characteristics) analysis - the objective is to localise known lesions correctly. The spatial resolution and noise of digitised clinical radiographs of the lumbar spine were altered by image processing, and pathological structures were added to the images for the FFE experiment. The images were printed to film and evaluated by seven European expert radiologists using VGA and FFE. The results of these two different methods showed a very good agreement. VGA methodology can be made as solid as the FFE experiment for evaluating image quality. The simplicity of VGA makes it very suitable for implementation in clinical practice. (author)

  17. Evaluation of X ray attenuation by means of radiographic images

    International Nuclear Information System (INIS)

    Barros, Frieda Saicla; Paredes, Ramon S.C.; Godoi, Walmor C.; Souza, Gabriel Pinto de

    2011-01-01

    This paper's main goal is to adopt a qualitative methodology to evaluate the attenuation of x-radiation through X-ray images in polymeric materials plus residual lead. To determinate the images it was initially used an experimental setup at the Laboratory for Materials Diagnostics LACTEC. These results correspond to a more qualitative analysis, even with quantitative answers. Through analysis of radiographic images we can measure the intensity of radiation that goes through the plate, making possible to establish a relationship between the attenuation coefficient and the thickness of the material. (author)

  18. Characterization of the Ljubljana TRIGA thermal column neutron radiographic facility

    International Nuclear Information System (INIS)

    Nemec, T.; Rant, J.; Kristof, E.; Glumac, B.

    1995-01-01

    An extensive characterization of the neutron beam of the existing neutron radiographic facility in the thermal column of the Ljubljana Triga Mark II research reactor is in progress. Neutron beam characteristics are needed to determine the effect of various neutron and gamma radiation on the neutron radiographic image. Commercially available medical scintillator converter screens based on Gd dioxy sulphite as well as Gd metal neutron converters are used to record neutron radiographic image. Thermal, epithermal and fast neutron fluxes were measured using Au and In activation detectors and cadmium ratio is determined. Neutron beam flux profiles are measured by film densitometry and by Au activation detector wires. By exposing films shielded by boral or lead plates individual contributions of thermal, epithermal neutrons and gamma radiation are estimated by densitometric measurements. By recording images of neutron image quality indicators BPI (Beam Purity Indicator) and SI (Sensitivity Indicator) produced by Riso, standard neutron radiography image characteristic are established. In gamma dosimetric measurements thermoluminescent detectors (CaF 2 Mn) are used. (author)

  19. Atlas of Radiographic Features of Osteoarthritis of the Ankle and Hindfoot

    Science.gov (United States)

    Kraus, Virginia Byers; Kilfoil, Terrence M; Hash, Thomas W.; McDaniel, Gary; Renner, Jordan B; Carrino, John A.; Adams, Samuel

    2015-01-01

    Objective To develop a radiographic atlas of osteoarthritis (OA) for use as a template and guide for standardized scoring of radiographic features of OA of the ankle and hindfoot joints. Method Under Institutional Review Board approval, ankle and hindfoot images were selected from a cohort study and from among cases that underwent ankle radiography during a 6-month period at Duke University Medical Center. Missing OA pathology was obtained through supplementation of cases with the assistance of a foot and ankle specialist in Orthopaedic surgery and a musculoskeletal radiologist. Images were obtained and reviewed without patient identifying information. Images went through multiple rounds of review and final images were selected by consensus of the study team. For intra-rater and inter-rater reliability, the kappa statistic was calculated for two readings by 3 musculoskeletal radiologists, a minimum of two weeks apart, of ankle and hindfoot radiographs from 30 anonymized subjects. Results The atlas demonstrates individual radiographic features (osteophyte and joint space narrowing) and Kellgren Lawrence grade for all aspects of the talocrural (ankle joint proper) and talocalcaneal (subtalar) joints. Reliability of scoring based on the atlas was quite good to excellent for most features indicated. Additional examples of ankle joint findings are illustrated including sclerosis, os trigonum, subchondral cysts and talar tilt. Conclusions It is anticipated that this atlas will assist with standardization of scoring of ankle and hindfoot OA by basic and clinical OA researchers. PMID:26318654

  20. Atlas of radiographic features of osteoarthritis of the ankle and hindfoot.

    Science.gov (United States)

    Kraus, V B; Kilfoil, T M; Hash, T W; McDaniel, G; Renner, J B; Carrino, J A; Adams, S

    2015-12-01

    To develop a radiographic atlas of osteoarthritis (OA) for use as a template and guide for standardized scoring of radiographic features of OA of the ankle and hindfoot joints. Under Institutional Review Board approval, ankle and hindfoot images were selected from a cohort study and from among cases that underwent ankle radiography during a 6-month period at Duke University Medical Center. Missing OA pathology was obtained through supplementation of cases with the assistance of a foot and ankle specialist in Orthopaedic surgery and a musculoskeletal radiologist. Images were obtained and reviewed without patient identifying information. Images went through multiple rounds of review and final images were selected by consensus of the study team. For intra-rater and inter-rater reliability, the kappa statistic was calculated for two readings by three musculoskeletal radiologists, a minimum of two weeks apart, of ankle and hindfoot radiographs from 30 anonymized subjects. The atlas demonstrates individual radiographic features (osteophyte and joint space narrowing (JSN)) and Kellgren-Lawrence grade for all aspects of the talocrural (ankle joint proper) and talocalcaneal (subtalar) joints. Reliability of scoring based on the atlas was quite good to excellent for most features indicated. Additional examples of ankle joint findings are illustrated including sclerosis, os trigonum, subchondral cysts and talar tilt. It is anticipated that this atlas will assist with standardization of scoring of ankle and hindfoot OA by basic and clinical OA researchers. Copyright © 2015 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  1. Stereoscopic radiographic images with gamma source encoding

    International Nuclear Information System (INIS)

    Strocovsky, S.G.; Otero, D

    2012-01-01

    Conventional radiography with X-ray tube has several drawbacks, as the compromise between the size of the focal spot and the fluence. The finite dimensions of the focal spot impose a limit to the spatial resolution. Gamma radiography uses gamma-ray sources which surpass in size, portability and simplicity to X-ray tubes. However, its low intrinsic fluence forces to use extended sources that also degrade the spatial resolution. In this work, we show the principles of a new radiographic technique that overcomes the limitations associated with the finite dimensions of X-ray sources, and that offers additional benefits to conventional techniques. The new technique called coding source imaging (CSI), is based on the use of extended sources, edge-encoding of radiation and differential detection. The mathematical principles and the method of images reconstruction with the new proposed technique are explained in the present work. Analytical calculations were made to determine the maximum spatial resolution and the variables on which it depends. The CSI technique was tested by means of Monte Carlo simulations with sets of spherical objects. We show that CSI has stereoscopic capabilities and it can resolve objects smaller than the source size. The CSI decoding algorithm reconstructs simultaneously four different projections from the same object, while conventional radiography produces only one projection per acquisition. Projections are located in separate image fields on the detector plane. Our results show it is possible to apply an extremely simple radiographic technique with extended sources, and get 3D information of the attenuation coefficient distribution for simple geometry objects in a single acquisition. The results are promising enough to evaluate the possibility of future research with more complex objects typical of medical diagnostic radiography and industrial gamma radiography (author)

  2. A computer-aided diagnosis system to detect pathologies in temporal subtraction images of chest radiographs

    Science.gov (United States)

    Looper, Jared; Harrison, Melanie; Armato, Samuel G.

    2016-03-01

    Radiologists often compare sequential radiographs to identify areas of pathologic change; however, this process is prone to error, as human anatomy can obscure the regions of change, causing the radiologists to overlook pathology. Temporal subtraction (TS) images can provide enhanced visualization of regions of change in sequential radiographs and allow radiologists to better detect areas of change in radiographs. Not all areas of change shown in TS images, however, are actual pathology. The purpose of this study was to create a computer-aided diagnostic (CAD) system that identifies which regions of change are caused by pathology and which are caused by misregistration of the radiographs used to create the TS image. The dataset used in this study contained 120 images with 74 pathologic regions on 54 images outlined by an experienced radiologist. High and low ("light" and "dark") gray-level candidate regions were extracted from the images using gray-level thresholding. Then, sampling techniques were used to address the class imbalance problem between "true" and "false" candidate regions. Next, the datasets of light candidate regions, dark candidate regions, and the combined set of light and dark candidate regions were used as training and testing data for classifiers by using five-fold cross validation. Of the classifiers tested (support vector machines, discriminant analyses, logistic regression, and k-nearest neighbors), the support vector machine on the combined candidates using synthetic minority oversampling technique (SMOTE) performed best with an area under the receiver operating characteristic curve value of 0.85, a sensitivity of 85%, and a specificity of 84%.

  3. Geometric correction of radiographic images using general purpose image processing program

    International Nuclear Information System (INIS)

    Kim, Eun Kyung; Cheong, Ji Seong; Lee, Sang Hoon

    1994-01-01

    The present study was undertaken to compare geometric corrected image by general-purpose image processing program for the Apple Macintosh II computer (NIH Image, Adobe Photoshop) with standardized image by individualized custom fabricated alignment instrument. Two non-standardized periapical films with XCP film holder only were taken at the lower molar portion of 19 volunteers. Two standardized periapical films with customized XCP film holder with impression material on the bite-block were taken for each person. Geometric correction was performed with Adobe Photoshop and NIH Image program. Specially, arbitrary image rotation function of 'Adobe Photoshop' and subtraction with transparency function of 'NIH Image' were utilized. The standard deviations of grey values of subtracted images were used to measure image similarity. Average standard deviation of grey values of subtracted images if standardized group was slightly lower than that of corrected group. However, the difference was found to be statistically insignificant (p>0.05). It is considered that we can use 'NIH Image' and 'Adobe Photoshop' program for correction of nonstandardized film, taken with XCP film holder at lower molar portion.

  4. Effect of quality control implementation on image quality of radiographic films and irradiation doses to patients

    International Nuclear Information System (INIS)

    Cheng Yuxi; Zhou Qipu; Ge Lijuan; Hou Changsong; Qi Xuesong; Yue Baorong; Wang Zuoling; Wei Kedao

    1999-01-01

    Objective: To study the changes in the image quality of radiographic films and the irradiation doses to patients after quality control (QC) implementation. Methods: The entrance surface doses (ESD) to patients measured with TLD and the image quality of radiographic films were evaluated on the basis of CEC image quality criteria. Results: The ESD to patients were significantly reduced after QC implementation (P 0.05), but the post-QC image quality was significantly improved in chest PA, lumbar spine AP and pelvis AP(P0.01 or P<0.05). Conclusion: Significantly reduced irradiation dose with improved image quality can be obtained by QC implementation

  5. The effect of perceived organizational support on organizational commitment of diagnostic imaging radiographers

    International Nuclear Information System (INIS)

    Makanjee, Chandra Rekha; Hartzer, Yolanda F.; Uys, Ilse L.

    2006-01-01

    This article arises from a research project investigating the effects of occupational stress and organizational commitment of diagnostic imaging radiographers on rendering quality service. One of the main aims of this project was to determine the extent to which perceived organizational support influenced commitment of radiographers to the organization, to reduce turnover intent and quality of service rendered. A descriptive correlation study design, based on questionnaires completed by 119 radiographers from 11 organizations, revealed that organizational commitment was moderate towards a tendency of poor. A positive relationship was found between various antecedents of perceived organizational support and organizational commitment (mainly affective and normative), indicating that perceived organizational support positively influenced radiographers' organizational commitment. There is a clear indication of turnover intent, which in turn has a negative impact on rendering quality service. In conclusion, to reduce turnover intent, and improve quality of service rendered, management needs to play an important role in creating a positive working environment for radiographers to perform their tasks

  6. Radiographic and magnetic resonance imaging of the stifle joint in experimental osteoarthritis of dogs

    International Nuclear Information System (INIS)

    Widmer, W.R.; Buckwalter, K.A.; Braunstein, E.M.; Hill, M.A.; O'Connor, B.L.; Visco, D.M.

    1994-01-01

    Radiography and magnetic resonance imaging were used to evaluate osteoarthritis at 2, 6, and 12 weeks following transection of the cranial cruciate ligament of the stifle (femorotibial) joint of 6 dogs. A quantitative radiographic scoring system was used to assess the progression of hard and soft tissue changes of osteoarthritis. Mediolateral (flexed joint) and oblique (extended joint) radiographic projections enabled identification of small osteophytes on the femoral trochlear ridges, which were detected at an earlier stage of development than was previously reported. Magnetic resonance imaging was useful in detecting changes in cartilage thickness, osteophytosis and intraarticular loose bodies. Radiography and magnetic resonance imaging were complementary in the assessment of pathologic changes of osteoarthritis

  7. ISSLS PRIZE IN BIOENGINEERING SCIENCE 2018: dynamic imaging of degenerative spondylolisthesis reveals mid-range dynamic lumbar instability not evident on static clinical radiographs.

    Science.gov (United States)

    Dombrowski, Malcolm E; Rynearson, Bryan; LeVasseur, Clarissa; Adgate, Zach; Donaldson, William F; Lee, Joon Y; Aiyangar, Ameet; Anderst, William J

    2018-04-01

    Degenerative spondylolisthesis (DS) in the setting of symptomatic lumbar spinal stenosis is commonly treated with spinal fusion in addition to decompression with laminectomy. However, recent studies have shown similar clinical outcomes after decompression alone, suggesting that a subset of DS patients may not require spinal fusion. Identification of dynamic instability could prove useful for predicting which patients are at higher risk of post-laminectomy destabilization necessitating fusion. The goal of this study was to determine if static clinical radiographs adequately characterize dynamic instability in patients with lumbar degenerative spondylolisthesis (DS) and to compare the rotational and translational kinematics in vivo during continuous dynamic flexion activity in DS versus asymptomatic age-matched controls. Seven patients with symptomatic single level lumbar DS (6 M, 1 F; 66 ± 5.0 years) and seven age-matched asymptomatic controls (5 M, 2 F age 63.9 ± 6.4 years) underwent biplane radiographic imaging during continuous torso flexion. A volumetric model-based tracking system was used to track each vertebra in the radiographic images using subject-specific 3D bone models from high-resolution computed tomography (CT). In vivo continuous dynamic sagittal rotation (flexion/extension) and AP translation (slip) were calculated and compared to clinical measures of intervertebral flexion/extension and AP translation obtained from standard lateral flexion/extension radiographs. Static clinical radiographs underestimate the degree of AP translation seen on dynamic in vivo imaging (1.0 vs 3.1 mm; p = 0.03). DS patients demonstrated three primary motion patterns compared to a single kinematic pattern in asymptomatic controls when analyzing continuous dynamic in vivo imaging. 3/7 (42%) of patients with DS demonstrated aberrant mid-range motion. Continuous in vivo dynamic imaging in DS reveals a spectrum of aberrant motion with significantly greater

  8. Radiographic evaluation of the maxillary sinus prior to dental implant therapy: A comparison between two dimensional and three dimensional radiographic imaging

    Energy Technology Data Exchange (ETDEWEB)

    Tadinada, Aditya; Fung, Karen; Thacker, Sejal; Mahdian, Mina; Jadhaw, Aniket; Schincaglia, Gian Pietro [University of Connecticut School of Dental Medicine, Farmington (United States)

    2015-09-15

    This study was performed to evaluate the diagnostic efficacy of panoramic radiography and cone-beam computed tomography (CBCT) in detecting sinus pathology. This study was based on a retrospective evaluation of patients who had undergone both a panoramic radiograph and a CBCT exam. A total of 100 maxillary sinuses were evaluated. Four examiners with various levels of expertise evaluated the images using a five-point scoring system. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic efficacy of the two modalities. The image analysis was repeated twice, with at least two weeks between the evaluation sessions. Interobserver reliability was assessed using Cronbach's alpha, and intraobserver reliability was assessed using Cohen's kappa. Maxillary sinus pathology was detected in 72% of the patients. High interobserver and intraobserver reliability were observed for both imaging modalities and among the four examiners. Statistical analyses using ROC curves demonstrated that the CBCT images had a larger area under the curve (0.940) than the panoramic radiographs (0.579). Three-dimensional evaluation of the sinus with CBCT was significantly more reliable in detecting pathology than panoramic imaging.

  9. A survey of radiographers' confidence and self-perceived accuracy in frontline image interpretation and their continuing educational preferences

    Energy Technology Data Exchange (ETDEWEB)

    Neep, Michael J [Department of Medical Imaging, Princess Alexandra Hospital, Brisbane, Queensland (Australia); Centre for Functioning and Health Research, Metro South Health, Brisbane, Queensland (Australia); School of Public Health and Social Work and Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland (Australia); Steffens, Tom [Department of Medical Imaging, Princess Alexandra Hospital, Brisbane, Queensland (Australia); Owen, Rebecca [Radiation Oncology Mater Centre, Princess Alexandra Hospital, Brisbane, Queensland (Australia); Faculty of Health, Queensland University of Technology, Brisbane, Queensland (Australia); McPhail, Steven M [Centre for Functioning and Health Research, Metro South Health, Brisbane, Queensland (Australia); School of Public Health and Social Work and Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland (Australia); Department of Medical Imaging, Princess Alexandra Hospital, Brisbane, Queensland (Australia)

    2014-06-15

    The provision of a written comment on traumatic abnormalities of the musculoskeletal system detected by radiographers can assist referrers and may improve patient management, but the practice has not been widely adopted outside the United Kingdom. The purpose of this study was to investigate Australian radiographers' perceptions of their readiness for practice in a radiographer commenting system and their educational preferences in relation to two different delivery formats of image interpretation education, intensive and non-intensive. A cross-sectional web-based questionnaire was implemented between August and September 2012. Participants included radiographers with experience working in emergency settings at four Australian metropolitan hospitals. Conventional descriptive statistics, frequency histograms, and thematic analysis were undertaken. A Wilcoxon signed-rank test examined whether a difference in preference ratings between intensive and non-intensive education delivery was evident. The questionnaire was completed by 73 radiographers (68% response rate). Radiographers reported higher confidence and self-perceived accuracy to detect traumatic abnormalities than to describe traumatic abnormalities of the musculoskeletal system. Radiographers frequently reported high desirability ratings for both the intensive and the non-intensive education delivery, no difference in desirability ratings for these two formats was evident (z = 1.66, P = 0.11). Some Australian radiographers perceive they are not ready to practise in a frontline radiographer commenting system. Overall, radiographers indicated mixed preferences for image interpretation education delivered via intensive and non-intensive formats. Further research, preferably randomised trials, investigating the effectiveness of intensive and non-intensive education formats of image interpretation education for radiographers is warranted.

  10. A survey of radiographers' confidence and self-perceived accuracy in frontline image interpretation and their continuing educational preferences

    International Nuclear Information System (INIS)

    Neep, Michael J; Steffens, Tom; Owen, Rebecca; McPhail, Steven M

    2014-01-01

    The provision of a written comment on traumatic abnormalities of the musculoskeletal system detected by radiographers can assist referrers and may improve patient management, but the practice has not been widely adopted outside the United Kingdom. The purpose of this study was to investigate Australian radiographers' perceptions of their readiness for practice in a radiographer commenting system and their educational preferences in relation to two different delivery formats of image interpretation education, intensive and non-intensive. A cross-sectional web-based questionnaire was implemented between August and September 2012. Participants included radiographers with experience working in emergency settings at four Australian metropolitan hospitals. Conventional descriptive statistics, frequency histograms, and thematic analysis were undertaken. A Wilcoxon signed-rank test examined whether a difference in preference ratings between intensive and non-intensive education delivery was evident. The questionnaire was completed by 73 radiographers (68% response rate). Radiographers reported higher confidence and self-perceived accuracy to detect traumatic abnormalities than to describe traumatic abnormalities of the musculoskeletal system. Radiographers frequently reported high desirability ratings for both the intensive and the non-intensive education delivery, no difference in desirability ratings for these two formats was evident (z = 1.66, P = 0.11). Some Australian radiographers perceive they are not ready to practise in a frontline radiographer commenting system. Overall, radiographers indicated mixed preferences for image interpretation education delivered via intensive and non-intensive formats. Further research, preferably randomised trials, investigating the effectiveness of intensive and non-intensive education formats of image interpretation education for radiographers is warranted

  11. Method of simulating spherical voids for use as a radiographic standard

    International Nuclear Information System (INIS)

    Foster, B.E.

    1977-01-01

    A method of simulating small spherical voids in metal is provided. The method entails drilling or etching a hemispherical depression of the desired diameter in each of two sections of metal, the sections being flat plates or different diameter cylinders. A carbon bead is placed in one of the hemispherical voids and is used as a guide to align the second hemispherical void with that in the other plate. The plates are then bonded together with epoxy, tape or similar material and the two aligned hemispheres form a sphere within the material; thus a void of a known size has been created. This type of void can be used to simulate a pore in the development of radiographic techniques of actual voids (porosity) in welds and serve as a radiographic standard

  12. Diagnostic imaging of psoriatic arthritis. Part I: etiopathogenesis, classifications and radiographic features

    Directory of Open Access Journals (Sweden)

    Iwona Sudoł-Szopińska

    2016-03-01

    Full Text Available Psoriatic arthritis is one of the spondyloarthritis. It is a disease of clinical heterogenicity, which may affect peripheral joints, as well as axial spine, with presence of inflammatory lesions in soft tissue, in a form of dactylitis and enthesopathy. Plain radiography remains the basic imaging modality for PsA diagnosis, although early inflammatory changes affecting soft tissue and bone marrow cannot be detected with its use, or the image is indistinctive. Typical radiographic features of PsA occur in an advanced disease, mainly within the synovial joints, but also in fibrocartilaginous joints, such as sacroiliac joints, and additionally in entheses of tendons and ligaments. Moll and Wright classified PsA into 5 subtypes: asymmetric oligoarthritis, symmetric polyarthritis, arthritis mutilans, distal interphalangeal arthritis of the hands and feet and spinal column involvement. In this part of the paper we discuss radiographic features of the disease. The next one will address magnetic resonance imaging and ultrasonography.

  13. Evaluation of pneumonia in children: comparison of MRI with fast imaging sequences at 1.5T with chest radiographs

    Energy Technology Data Exchange (ETDEWEB)

    Yikilmaz, Ali; Koc, Ali; Coskun, Abdulhakim (Dept. of Radiology, Erciyes Medical School, Kayseri (Turkey)); Ozturk, Mustafa K (Dept. of Pediatric Infectious Diseases, Erciyes Medical School, Kayseri (Turkey)); Mulkern, Robert V; Lee, Edward Y (Dept. of Radiology and Dept. of Medicine, Pulmonary Div., Children' s Hospital Boston and Harvard Medical School, Boston (United States)), email: Edward.lee@childrens.harvard.edu

    2011-10-15

    Background Although there has been a study aimed at magnetic resonance imaging (MRI) evaluation of pneumonia in children at a low magnetic field (0.2T), there is no study which assessed the efficacy of MRI, particularly with fast imaging sequences at 1.5T, for evaluating pneumonia in children. Purpose To investigate the efficacy of chest MRI with fast imaging sequences at 1.5T for evaluating pneumonia in children by comparing MRI findings with those of chest radiographs. Material and Methods This was an Institutional Review Board-approved, HIPPA-compliant prospective study of 40 consecutive pediatric patients (24 boys, 16 girls; mean age 7.3 years +- 6.6 years) with pneumonia, who underwent PA and lateral chest radiographs followed by MRI within 24 h. All MRI studies were obtained in axial and coronal planes with two different fast imaging sequences: T1-weighted FFE (Fast Field Echo) (TR/TE: 83/4.6) and T2-weighted B-FFE M2D (Balanced Fast Field Echo Multiple 2D Dimensional) (TR/TE: 3.2/1.6). Two experienced pediatric radiologists reviewed each chest radiograph and MRI for the presence of consolidation, necrosis/abscess, bronchiectasis, and pleural effusion. Chest radiograph and MRI findings were compared with Kappa statistics. Results All consolidation, lung necrosis/abscess, bronchiectasis, and pleural effusion detected with chest radiographs were also detected with MRI. There was statistically substantial agreement between chest radiographs and MRI in detecting consolidation (k = 0.78) and bronchiectasis (k = 0.72) in children with pneumonia. The agreement between chest radiographs and MRI was moderate for detecting necrosis/abscess (k = 0.49) and fair for detecting pleural effusion (k = 0.30). Conclusion MRI with fast imaging sequences is comparable to chest radiographs for evaluating underlying pulmonary consolidation, bronchiectasis, necrosis/abscess, and pleural effusion often associated with pneumonia in children

  14. Radiographic signs and diagnosis of dental disease

    International Nuclear Information System (INIS)

    Bellows, J.

    1993-01-01

    Dental radiographs are critical for the complete assessment and treatment of dental diseases. Dental radiography is commonly used to evaluate congenital dental defects, periodontal disease, orthodontic manipulations, oral tumors, endodontic treatments, oral trauma, and any situation where an abnormality is suspected. Although standard radiographic equipment and film can be used to produce dental radiographs, dental X-ray equipment and film provide superior quality images and greater convenience of animal patient positioning. An understanding of normal dental radiographic anatomy is important when interpreting dental radiographs. Stage III periodontitis is the earliest stage of periodontal disease at which radiographic abnormalities become apparent. Bone loss associated with periodontal disease can be classified as either horizontal or vertical. Periapical radiolucencies can represent granulomas, cysts, or abscesses, whereas periapical radiodensities may represent sclerotic bone or condensing osteitis. Lytic lesions of the bone of the jaw often represent oral neoplasms. Neoplasms also can displace or disrupt teeth in the dental arch. Resorptive lesions can be external or internal and appear as radiolucent areas involving the external surface of the root or the pulp cavity, respectively. Feline dental resorptive lesions, also known as odontoclastic resorptions, are a specific form of dental resorptive lesions unique to cats

  15. Development and image quality assessment of a contrast-enhancement algorithm for display of digital chest radiographs

    International Nuclear Information System (INIS)

    Rehm, K.

    1992-01-01

    This dissertation presents a contrast-enhancement algorithm Artifact-Suppressed Adaptive Histogram Equalization (ASAHE). This algorithm was developed as part of a larger effort to replace the film radiographs currently used in radiology departments with digital images. Among the expected benefits of digital radiology are improved image management and greater diagnostic accuracy. Film radiographs record X-ray transmission data at high spatial resolution, and a wide dynamic range of signal. Current digital radiography systems record an image at reduced spatial resolution and with coarse sampling of the available dynamic range. These reductions have a negative impact on diagnostic accuracy. The contrast-enhancement algorithm presented in this dissertation is designed to boost diagnostic accuracy of radiologists using digital images. The ASAHE algorithm is an extension of an earlier technique called Adaptive Histogram Equalization (AHE). The AHE algorithm is unsuitable for chest radiographs because it over-enhances noise, and introduces boundary artifacts. The modifications incorporated in ASAHE suppress the artifacts and allow processing of chest radiographs. This dissertation describes the psychophysical methods used to evaluate the effects of processing algorithms on human observer performance. An experiment conducted with anthropomorphic phantoms and simulated nodules showed the ASAHE algorithm to be superior for human detection of nodules when compared to a computed radiography system's algorithm that is in current use. An experiment conducted using clinical images demonstrating pneumothoraces (partial lung collapse) indicated no difference in human observer accuracy when ASAHE images were compared to computed radiography images, but greater ease of diagnosis when ASAHE images were used. These results provide evidence to suggest that Artifact-Suppressed Adaptive Histogram Equalization can be effective in increasing diagnostic accuracy and efficiency

  16. Measuring stone surface area from a radiographic image is accurate and reproducible with the help of an imaging program.

    Science.gov (United States)

    Kurien, Abraham; Ganpule, Arvind; Muthu, V; Sabnis, R B; Desai, Mahesh

    2009-01-01

    The surface area of the stone from a radiographic image is one of the more suitable parameters defining stone bulk. The widely accepted method of measuring stone surface area is to count the number of square millimeters enclosed within a tracing of the stone outline on graph paper. This method is time consuming and cumbersome with potential for human error, especially when multiple measurements are needed. The purpose of this study was to evaluate the accuracy, efficiency, and reproducibility of a commercially available imaging program, Adobe Photoshop 7.0 for the measurement of stone surface area. The instructions to calculate area using the software are simple and easy in a Windows-based format. The accuracy of the imaging software was estimated by measuring surface areas of shapes of known mathematical areas. The efficiency and reproducibility were then evaluated from radiographs of 20 persons with radiopaque upper-tract urinary stones. The surface areas of stone images were measured using both graph paper and imaging software. Measurements were repeated after 10 days to assess the reproducibility of the techniques. The time taken to measure the area by the two methods was also assessed separately. The accuracy of the imaging software was estimated to be 98.7%. The correlation coefficient between the two methods was R(2) = 0.97. The mean percentage variation using the imaging software was 0.68%, while it was 6.36% with the graph paper. The mean time taken to measure using the image analyzer and graph paper was 1.9 +/- 0.8 minutes and 4.5 +/- 1.08 minutes, respectively (P stone surface area from radiographs compared with manual measurements using graph paper.

  17. Defect sizing of post-irradiated nuclear fuels using grayscale thresholding in their radiographic images

    International Nuclear Information System (INIS)

    Chaudhary, Usman Khurshid; Iqbal, Masood; Ahmad, Munir

    2010-01-01

    Quantification of different types of material defects in a number of reference standard post-irradiated nuclear fuel image samples have been carried out by virtue of developing a computer program that takes radiographic images of the fuel as input. The program is based on user adjustable grayscale thresholding in the regime of image segmentation whereby it selects and counts the pixels having graylevel values less than or equal to the computed threshold. It can size the defects due to chipping in nuclear fuel, cracks, voids, melting, deformation, inclusion of foreign materials, heavy isotope accumulation, non-uniformity, etc. The classes of fuel range from those of research and power reactors to fast breeders and from pellets to annular and vibro-compacted fuel. The program has been validated against ground truth realities of some locally fabricated metallic plates having drilled holes of known sizes simulated as defects in them in which the results indicate that it either correctly selects and quantifies at least 94% of the actual required regions of interest in a given image or it gives less than 8.1% false alarm rate. Also, the developed program is independent of image size.

  18. Defect sizing of post-irradiated nuclear fuels using grayscale thresholding in their radiographic images

    Energy Technology Data Exchange (ETDEWEB)

    Chaudhary, Usman Khurshid, E-mail: ukhurshid@hotmail.co [Department of Physics and Applied Mathematics, Pakistan Institute of Engineering and Applied Sciences, P.O. Nilore, Islamabad 45650 (Pakistan); Iqbal, Masood, E-mail: masiqbal@hotmail.co [Nuclear Engineering Division, Pakistan Institute of Nuclear Science and Technology, P.O. Nilore, Islamabad 45650 (Pakistan); Ahmad, Munir [Nondestructive Testing Group, Directorate of Technology, Pakistan Institute of Nuclear Science and Technology, P.O. Nilore, Islamabad 45650 (Pakistan)

    2010-10-15

    Quantification of different types of material defects in a number of reference standard post-irradiated nuclear fuel image samples have been carried out by virtue of developing a computer program that takes radiographic images of the fuel as input. The program is based on user adjustable grayscale thresholding in the regime of image segmentation whereby it selects and counts the pixels having graylevel values less than or equal to the computed threshold. It can size the defects due to chipping in nuclear fuel, cracks, voids, melting, deformation, inclusion of foreign materials, heavy isotope accumulation, non-uniformity, etc. The classes of fuel range from those of research and power reactors to fast breeders and from pellets to annular and vibro-compacted fuel. The program has been validated against ground truth realities of some locally fabricated metallic plates having drilled holes of known sizes simulated as defects in them in which the results indicate that it either correctly selects and quantifies at least 94% of the actual required regions of interest in a given image or it gives less than 8.1% false alarm rate. Also, the developed program is independent of image size.

  19. A pilot study to determine the effect of radiographer training on radiostereometric analysis imaging technique

    DEFF Research Database (Denmark)

    Muharemovic, O; Troelsen, A; Thomsen, M G

    2018-01-01

    INTRODUCTION: Producing x-ray images for radiostereometric analysis (RSA) is a demanding technique. Suboptimal examinations result in a high percentage of exposure repetition. The aim of this pilot study was to use an experiential training approach to sharpen the skills of radiographers in acquir......INTRODUCTION: Producing x-ray images for radiostereometric analysis (RSA) is a demanding technique. Suboptimal examinations result in a high percentage of exposure repetition. The aim of this pilot study was to use an experiential training approach to sharpen the skills of radiographers...

  20. Significance of radiographic abnormalities in patients with tibial stress injuries: correlation with magnetic resonance imaging

    International Nuclear Information System (INIS)

    Kijowski, Richard; Choi, James; Smet, Arthur de; Mukharjee, Rajat

    2007-01-01

    The objective was to correlate radiographic findings with magnetic resonance imaging (MRI) findings in patients with suspected tibial stress injuries in order to determine the significance of radiographic signs of stress injury in these individuals. The study group consisted of 80 patients with suspected tibial stress injuries who underwent a radiographic and MR examination of the tibia. Nineteen patients had bilateral involvement. Thus, a total of 99 tibias were evaluated. All radiographs and MR examinations were retrospectively reviewed, 1 month apart, in consensus by two musculoskeletal radiologists. The radiographs were reviewed without knowledge of the site of the clinical symptoms. Fisher's exact tests were used to determine the association between a positive radiograph and the presence of various MRI signs of a high-grade stress injury. There was a strong association between the presence of periosteal reaction on radiographs at the site of the clinical symptoms and a Fredericson grade 4 stress injury on MRI. The presence of periosteal reaction on radiographs at the site of clinical symptoms is predictive of a high-grade stress injury by MRI criteria. (orig.)

  1. Radiographer commenting of trauma radiographs: a survey of the benefits, barriers and enablers to participation in an Australian healthcare setting

    International Nuclear Information System (INIS)

    Neep, Michael J.; Steffens, Tom; Owen, Rebecca; McPhail, Steven M.

    2014-01-01

    Radiographer abnormality detection systems that highlight abnormalities on trauma radiographs ('red dot' system) have been operating for more than 30 years. Recently, a number of pitfalls have been identified. These limitations initiated the evolution of a radiographer commenting system, whereby a radiographer provides a brief description of abnormalities identified in emergency healthcare settings. This study investigated radiographers' participation in abnormality detection systems, their perceptions of benefits, barriers and enablers to radiographer commenting, and perceptions of potential radiographer image interpretation services for emergency settings. A cross-sectional survey was implemented. Participants included radiographers from four metropolitan hospitals in Queensland, Australia. Conventional descriptive statistics, histograms and thematic analysis were undertaken. Seventy-three surveys were completed and included in the analysis (68% response rate); 30 (41%) of respondents reported participating in abnormality detection in 20% or less of examinations, and 26(36%) reported participating in 80% or more of examinations. Five overarching perceived benefits of radiographer commenting were identified: assisting multidisciplinary teams, patient care, radiographer ability, professional benefits and quality of imaging. Frequently reported perceived barriers included 'difficulty accessing image interpretation education', 'lack of time' and 'low confidence in interpreting radiographs'. Perceived enablers included 'access to image interpretation education' and 'support from radiologist colleagues'. A range of factors are likely to contribute to the successful implementation of radiographer commenting in addition to abnormality detection in emergency settings. Effective image interpretation education amenable to completion by radiographers would likely prove valuable in preparing radiographers for participation in abnormality detection and commenting systems in

  2. Study on evaluation method for image quality of radiograph by step plate, (2)

    International Nuclear Information System (INIS)

    Terada, Yukihiro; Hirayama, Kazuo; Katoh, Mitsuaki.

    1992-01-01

    Recently, penetrameter sensitivity is used not only for the evaluation of radiographic image quality but also as a control method for examination conditions. However, it is necessary to take the parametric data for radiation quality in order to use it for the second purpose. The quantitative factor of radiation quality is determined by the absorption coefficient and the ratio of scattered radiation to transmitted radiation reaching the X-ray film. When the X-ray equipment changes in conducting the radiographic examination, these data must be measured in each case. This is a demerit in controlling examination conditions based on parametric data. As shown theoretically in the first report, the image quality value of a step plate which is defined by the density difference divided by film contrast and step plate thickness is useful to obtain the value of the radiation quality factor. This report deal with experimental investigation to measure it with the step plate. The result is showing that the value of the radiation quality factor calculated by the parametric data corresponded well with the image quality value measured by the step plate. Therefore, the convenient method to measure the value of the radiation quality factor has been established in order to control examination conditions in radiographic examination. (author)

  3. Improved detection of focal pneumonia by chest radiography with bone suppression imaging

    International Nuclear Information System (INIS)

    Li, Feng; Engelmann, Roger; Pesce, Lorenzo; Armato, Samuel G.; MacMahon, Heber

    2012-01-01

    To evaluate radiologists' ability to detect focal pneumonia by use of standard chest radiographs alone compared with standard plus bone-suppressed chest radiographs. Standard chest radiographs in 36 patients with 46 focal airspace opacities due to pneumonia (10 patients had bilateral opacities) and 20 patients without focal opacities were included in an observer study. A bone suppression image processing system was applied to the 56 radiographs to create corresponding bone suppression images. In the observer study, eight observers, including six attending radiologists and two radiology residents, indicated their confidence level regarding the presence of a focal opacity compatible with pneumonia for each lung, first by use of standard images, then with the addition of bone suppression images. Receiver operating characteristic (ROC) analysis was used to evaluate the observers' performance. The mean value of the area under the ROC curve (AUC) for eight observers was significantly improved from 0.844 with use of standard images alone to 0.880 with standard plus bone suppression images (P < 0.001) based on 46 positive lungs and 66 negative lungs. Use of bone suppression images improved radiologists' performance for detection of focal pneumonia on chest radiographs. (orig.)

  4. Improved detection of focal pneumonia by chest radiography with bone suppression imaging

    Energy Technology Data Exchange (ETDEWEB)

    Li, Feng; Engelmann, Roger; Pesce, Lorenzo; Armato, Samuel G.; MacMahon, Heber [University of Chicago, Department of Radiology, MC-2026, Chicago, IL (United States)

    2012-12-15

    To evaluate radiologists' ability to detect focal pneumonia by use of standard chest radiographs alone compared with standard plus bone-suppressed chest radiographs. Standard chest radiographs in 36 patients with 46 focal airspace opacities due to pneumonia (10 patients had bilateral opacities) and 20 patients without focal opacities were included in an observer study. A bone suppression image processing system was applied to the 56 radiographs to create corresponding bone suppression images. In the observer study, eight observers, including six attending radiologists and two radiology residents, indicated their confidence level regarding the presence of a focal opacity compatible with pneumonia for each lung, first by use of standard images, then with the addition of bone suppression images. Receiver operating characteristic (ROC) analysis was used to evaluate the observers' performance. The mean value of the area under the ROC curve (AUC) for eight observers was significantly improved from 0.844 with use of standard images alone to 0.880 with standard plus bone suppression images (P < 0.001) based on 46 positive lungs and 66 negative lungs. Use of bone suppression images improved radiologists' performance for detection of focal pneumonia on chest radiographs. (orig.)

  5. Development of a muon radiographic imaging electronic board system for a stable solar power operation

    Science.gov (United States)

    Uchida, T.; Tanaka, H. K. M.; Tanaka, M.

    2010-02-01

    Cosmic-ray muon radiography is a method that is used to study the internal structure of volcanoes. We have developed a muon radiographic imaging board with a power consumption low enough to be powered by a small solar power system. The imaging board generates an angular distribution of the muons. Used for real-time reading, the method may facilitate the prediction of eruptions. For real-time observations, the Ethernet is employed, and the board works as a web server for a remote operation. The angular distribution can be obtained from a remote PC via a network using a standard web browser. We have collected and analyzed data obtained from a 3-day field study of cosmic-ray muons at a Satsuma-Iwojima volcano. The data provided a clear image of the mountain ridge as a cosmic-ray muon shadow. The measured performance of the system is sufficient for a stand-alone cosmic-ray muon radiography experiment.

  6. Condylar guidance: correlation between protrusive interocclusal record and panoramic radiographic image: a pilot study.

    Science.gov (United States)

    Tannamala, Pavan Kumar; Pulagam, Mahesh; Pottem, Srinivas R; Swapna, B

    2012-04-01

    The purpose of this study was to compare the sagittal condylar angles set in the Hanau articulator by use of a method of obtaining an intraoral protrusive record to those angles found using a panoramic radiographic image. Ten patients, free of signs and symptoms of temporomandibular disorder and with intact dentition were selected. The dental stone casts of the subjects were mounted on a Hanau articulator with a springbow and poly(vinyl siloxane) interocclusal records. For all patients, the protrusive records were obtained when the mandible moved forward by approximately 6 mm. All procedures for recording, mounting, and setting were done in the same session. The condylar guidance angles obtained were tabulated. A panoramic radiographic image of each patient was made with the Frankfurt horizontal plane parallel to the floor of the mouth. Tracings of the radiographic images were made. The horizontal reference line was marked by joining the orbitale and porion. The most superior and most inferior points of the curvatures were identified. These two lines were connected by a straight line representing the mean curvature line. Angles made by the intersection of the mean curvature line and the horizontal reference line were measured. The results were subjected to statistical analysis with a significance level of p record method. The mean condylar guidance angle between the right and left side by both the methods was not statistically significant. The comparison of mean condylar guidance angles between the right side of the protrusive record method and the right side of the panoramic radiographic method and the left side of the protrusive record method and the left side of the panoramic radiographic method (p= 0.071 and p= 0.057, respectively) were not statistically significant. Within the limitations of this study, it was concluded that the protrusive condylar guidance angles obtained by panoramic radiograph may be used in programming semi-adjustable articulators. © 2012

  7. Determination of bone mineral density of the distal extremity of the radio in Rottweiller, by radiographic optic densitometry

    International Nuclear Information System (INIS)

    Alves, Jefferson Douglas Soares; Sterman, Franklin de Almeida

    2010-01-01

    This study allowed the standardization of the bone mineral density (BMD) of the distal extremity of the radio of 36 dogs adults in Rottweiler breed by radiographic optic densitometry. The limbs of the animals were radiographed with scale of aluminum that served as a reference. The radiographs images were digitalized and analyzed by a computer program for comparison of gray tones between the standard image and the image of the reference scale radiographed with the bone. Afterwards the values of density were expressed in millimeters of aluminum. Also studied the correlations between BMD and the sex, weight and external measures as the length of spine, height of the animal and circumference the distal extremity of the limb in study. The mean values and standard deviations of the bone mineral density of the distal extremity of the radio were: for the metaphyseal region the average of BMD of 7,88±0,89 mmAl, the diaphyseal region 1 the average of BMD of 8,58±0,80 mmAl and for diaphyseal region 2 of BMD of 9,00±0,74 mmAl. (author)

  8. Effect of adjusting kilovolt peak of the X-ray machine on radiographic-image quality in goldfish(Carassius auratus)

    International Nuclear Information System (INIS)

    Nut Nuanmanee; Dilok Wongsathein; Rutch Khattiya; Atigan Thongtharb; Utumma Maghanemi

    2008-01-01

    Objective: To find optimal kilovolt peak (kVp) for radiographic-image quality in Oranda fish with body width and depth ranging between 3-5 centimeters. Materials and Methods: 18 Oranda fish were divided into 6 groups (3 for each group). Body widths of fish in group 1, 2, and 3 were 3, 4, and 5 centimeters, respectively. Body depths of fish in group 4, 5, and 6 were 3, 4, and 5 centimeters, respectively. After the fish were anesthetized, the radiographic images of group 1, 2, and 3 were taken in lateral position with milliamperes (mA) at 50 mA and duration (sec) for 0.02, 0.05, and 0.05 sec, respectively. Kilovolt peak (kVp) was used in range from 40 to 58. In addition, the radiographic images of group 4, 5, and 6 were taken in dorsoventral position at 50 mA for 0.1 sec with varying kVp from 40 to 62. The quality of radiographic images was evaluated by 5 veterinarians and 5 radiologists. Results: The most appropriate kVp in lateral position with 3, 4 and 5 centimeters in body width were 44, 44, and 48, respectively. In addition, the most appropriate kVp in dorsoventral position with 3, 4, and 5 centimeters in body depth were 46, 48, and 50, respectively. Conclusion: The radiographic-image quality in Oranda fish was depended on the appropriated kVp

  9. Increase in the efficiency of radiographic inspection of welded joints for quality

    International Nuclear Information System (INIS)

    Feoktistov, V.A.; Polevik, V.A.; Korneev, V.A.

    1982-01-01

    The possibility of increasing the efficiency of radiographical inspection of metallic structures and pipelines welded joints for quality when mounting NPP equipment at the expense of a shorter exposure time is studied. The radiographic control has been conducted with X-ray RUP type instruments and ''Gammarid-25'' defectoscope. The exposure time is shown to be reduced when using active developers for processing radiograms. The sensitivity of radiographical images to X-ray and gamma-radiation increases when using D-82, D-72 active developers and ''roentgen-2'' standard developer for photochemical treatment

  10. Radiographic alterations of the frontal sinus morphology according to variations of the vertical angle in posteroanterior radiographs of the skull

    Directory of Open Access Journals (Sweden)

    Rhonan Ferreira Silva

    2014-03-01

    The frontal sinuses play a highly relevant role in comparative human identification processes. Since forensic radiology is a branch in the forensic sciences, adequate radiological analysis of the frontal sinuses is essential for comparative human identifications. The current study investigates radiographic morphological changes in the frontal sinuses according to vertical angle distortions in posteroanterior (PA radiographs. A standard PA radiograph of the skull of an adult was obtained. Eight addition PA radiographs were taken at different vertical angles. Frontal sinuses were analyzed qualitatively and quantitatively according to Ribeiro´s (2000 technique. Both qualitative and quantitative analyses revealed significant image distortions. Further, overlapping anatomical structures were reported when PA radiographs were analyzed in negative angulation distortions (from -10° to -40°. Positive and negative angular distortions up to 20º slightly affected the qualitative morphological analysis. However, 10° positive and negative distortions provided a significant interference in quantitative analysis and impaired the measuring process. Most forensic techniques for the analysis of frontal sinuses comprise measurements of morphological distances. Distortions of approximately 10° or over in vertical angulation of cranial PA radiographs should be avoided so that more accurate comparative human identifications could be achieved.

  11. Content Based Radiographic Images Indexing and Retrieval Using Pattern Orientation Histogram

    Directory of Open Access Journals (Sweden)

    Abolfazl Lakdashti

    2008-06-01

    Full Text Available Introduction: Content Based Image Retrieval (CBIR is a method of image searching and retrieval in a  database. In medical applications, CBIR is a tool used by physicians to compare the previous and current  medical images associated with patients pathological conditions. As the volume of pictorial information  stored in medical image databases is in progress, efficient image indexing and retrieval is increasingly  becoming a necessity.  Materials and Methods: This paper presents a new content based radiographic image retrieval approach  based on histogram of pattern orientations, namely pattern orientation histogram (POH. POH represents  the  spatial  distribution  of  five  different  pattern  orientations:  vertical,  horizontal,  diagonal  down/left,  diagonal down/right and non-orientation. In this method, a given image is first divided into image-blocks  and  the  frequency  of  each  type  of  pattern  is  determined  in  each  image-block.  Then,  local  pattern  histograms for each of these image-blocks are computed.   Results: The method was compared to two well known texture-based image retrieval methods: Tamura  and  Edge  Histogram  Descriptors  (EHD  in  MPEG-7  standard.  Experimental  results  based  on  10000  IRMA  radiography  image  dataset,  demonstrate  that  POH  provides  better  precision  and  recall  rates  compared to Tamura and EHD. For some images, the recall and precision rates obtained by POH are,  respectively, 48% and 18% better than the best of the two above mentioned methods.    Discussion and Conclusion: Since we exploit the absolute location of the pattern in the image as well as  its global composition, the proposed matching method can retrieve semantically similar medical images.

  12. Radiographic aspects of xeroradiography

    International Nuclear Information System (INIS)

    Rao, G.U.V.; Fatouros, P.P.

    1980-01-01

    The quality of a conventional radiographic image can be characterized in terms of five basic parameters; density, contrast, latitude, resolution and noise. Since xeroradiographic images exhibit very limited broad area contrasts, and image formation is predominantly due to edge enhancement, a straightforward description of image quality using the same five parameters is not adequate. A detailed study was made of the radiographic aspects of xeroradiography with special reference to mammography, and a summary of major findings to date with appropriate references to published papers is presented

  13. Adaptive pseudo-color enhancement method of weld radiographic images based on HSI color space and self-transformation of pixels

    Science.gov (United States)

    Jiang, Hongquan; Zhao, Yalin; Gao, Jianmin; Gao, Zhiyong

    2017-06-01

    The radiographic testing (RT) image of a steam turbine manufacturing enterprise has the characteristics of low gray level, low contrast, and blurriness, which lead to a substandard image quality. Moreover, it is not conducive for human eyes to detect and evaluate defects. This study proposes an adaptive pseudo-color enhancement method for weld radiographic images based on the hue, saturation, and intensity (HSI) color space and the self-transformation of pixels to solve these problems. First, the pixel's self-transformation is performed to the pixel value of the original RT image. The function value after the pixel's self-transformation is assigned to the HSI components in the HSI color space. Thereafter, the average intensity of the enhanced image is adaptively adjusted to 0.5 according to the intensity of the original image. Moreover, the hue range and interval can be adjusted according to personal habits. Finally, the HSI components after the adaptive adjustment can be transformed to display in the red, green, and blue color space. Numerous weld radiographic images from a steam turbine manufacturing enterprise are used to validate the proposed method. The experimental results show that the proposed pseudo-color enhancement method can improve image definition and make the target and background areas distinct in weld radiographic images. The enhanced images will be more conducive for defect recognition. Moreover, the image enhanced using the proposed method conforms to the human eye visual properties, and the effectiveness of defect recognition and evaluation can be ensured.

  14. Adaptive pseudo-color enhancement method of weld radiographic images based on HSI color space and self-transformation of pixels.

    Science.gov (United States)

    Jiang, Hongquan; Zhao, Yalin; Gao, Jianmin; Gao, Zhiyong

    2017-06-01

    The radiographic testing (RT) image of a steam turbine manufacturing enterprise has the characteristics of low gray level, low contrast, and blurriness, which lead to a substandard image quality. Moreover, it is not conducive for human eyes to detect and evaluate defects. This study proposes an adaptive pseudo-color enhancement method for weld radiographic images based on the hue, saturation, and intensity (HSI) color space and the self-transformation of pixels to solve these problems. First, the pixel's self-transformation is performed to the pixel value of the original RT image. The function value after the pixel's self-transformation is assigned to the HSI components in the HSI color space. Thereafter, the average intensity of the enhanced image is adaptively adjusted to 0.5 according to the intensity of the original image. Moreover, the hue range and interval can be adjusted according to personal habits. Finally, the HSI components after the adaptive adjustment can be transformed to display in the red, green, and blue color space. Numerous weld radiographic images from a steam turbine manufacturing enterprise are used to validate the proposed method. The experimental results show that the proposed pseudo-color enhancement method can improve image definition and make the target and background areas distinct in weld radiographic images. The enhanced images will be more conducive for defect recognition. Moreover, the image enhanced using the proposed method conforms to the human eye visual properties, and the effectiveness of defect recognition and evaluation can be ensured.

  15. Use of a sensitometric method in quality control of radiographic images

    International Nuclear Information System (INIS)

    Lima, A.A.; Furtado, A.P.A.; Nied, L.; Bacelar, A.; Pinto, A.L.A.; Acunha, B.

    1996-01-01

    A sensitometric method is used to evaluate the characteristic answer of several radiographic films and the quality of produced images. Data was collected daily in a period of three months. Results from this research show a disagreement of a 100% from the pattern of the sensitometric characteristics to the analysed films

  16. Calcification in calcium pyrophosphate dihydrate (CPPD) crystalline deposits in the knee: anatomic, radiographic, MR imaging, and histologic study in cadavers

    Energy Technology Data Exchange (ETDEWEB)

    Abreu, M.; Chung, C.B.; Lima, J.E. de; Trudell, D. [Department of Musculoskeletal Radiology, University of California, San Diego, VA San Diego Healthcare System, 3350 La Jolla Village Drive, CA 92162, San Diego (United States); Johnson, K.; Terkeltaub, R.; Resnick, D. [Department of Rheumatology, University of California, San Diego, VA San Diego Healthcare System, 3350 La Jolla Village Drive, CA 92162, San Diego (United States); Pe, S. [University of California, San Diego, VA San Diego Healthcare System, 3350 La Jolla Village Drive, CA 92162, San Diego (United States)

    2004-07-01

    To demonstrate and determine the frequency and location of calcification within cadaveric knees with or without calcification typical of calcium pyrophosphate dihydrate (CPPD), utilizing histologic, radiographic and MR imaging techniques. Ten cadaveric knees of elderly individuals that demonstrated no radiographic evidence of prior surgery or trauma were studied with MR imaging and subsequently sectioned in planes corresponding to those obtained with MR imaging. The slices were imaged with high-resolution radiography. Two musculoskeletal radiologists correlated the anatomic, MR and radiographic findings. Three of the knees, which did not demonstrate calcifications, were utilized as controls. Histologic sections were obtained from four knees that contained calcifications and from the three controls, and analyzed with special histologic stains that demonstrate phosphorus and calcium. Radiographic imaging and histologic analysis demonstrated widespread CPPD crystal deposition in four of the 10 knee specimens (40%). MR imaging demonstrated some calcifications only within the articular cartilage of the femoral condyles in three of the four (75%) specimens that had CPPD deposits. In all four specimens radiographs and histologic analysis were more sensitive than MR imaging. Histologic analysis demonstrated no evidence of CPPD crystals in the control specimens. MR imaging is insensitive to the presence of CPPD deposits in the knee, even when such deposits are widespread. Our study suggests that the sensitivity of MR imaging was significantly better in detecting CPPD deposits in the hyaline cartilage of the femoral condyles when compared with other internal structures, even when such structures contained a higher amount of calcification. (orig.)

  17. Super-resolution convolutional neural network for the improvement of the image quality of magnified images in chest radiographs

    Science.gov (United States)

    Umehara, Kensuke; Ota, Junko; Ishimaru, Naoki; Ohno, Shunsuke; Okamoto, Kentaro; Suzuki, Takanori; Shirai, Naoki; Ishida, Takayuki

    2017-02-01

    Single image super-resolution (SR) method can generate a high-resolution (HR) image from a low-resolution (LR) image by enhancing image resolution. In medical imaging, HR images are expected to have a potential to provide a more accurate diagnosis with the practical application of HR displays. In recent years, the super-resolution convolutional neural network (SRCNN), which is one of the state-of-the-art deep learning based SR methods, has proposed in computer vision. In this study, we applied and evaluated the SRCNN scheme to improve the image quality of magnified images in chest radiographs. For evaluation, a total of 247 chest X-rays were sampled from the JSRT database. The 247 chest X-rays were divided into 93 training cases with non-nodules and 152 test cases with lung nodules. The SRCNN was trained using the training dataset. With the trained SRCNN, the HR image was reconstructed from the LR one. We compared the image quality of the SRCNN and conventional image interpolation methods, nearest neighbor, bilinear and bicubic interpolations. For quantitative evaluation, we measured two image quality metrics, peak signal-to-noise ratio (PSNR) and structural similarity (SSIM). In the SRCNN scheme, PSNR and SSIM were significantly higher than those of three interpolation methods (pmethods without any obvious artifacts. These preliminary results indicate that the SRCNN scheme significantly outperforms conventional interpolation algorithms for enhancing image resolution and that the use of the SRCNN can yield substantial improvement of the image quality of magnified images in chest radiographs.

  18. Legalities of the radiograph

    International Nuclear Information System (INIS)

    Bundy, A.L.

    1988-01-01

    The radiograph itself plays a major role in medical malpractice cases. Also, many questions arise concerning the rights to and storage of x-ray films. These issues are addressed in this chapter. To keep the terminology simple, the word radiograph represents all imaging documentation on hard copy film (x-rays, nuclear medicine, computer-assisted studies, ultrasound, and magnetic resonance imaging)

  19. Radiographic examination for successful dental implant

    International Nuclear Information System (INIS)

    Lee, Sam Sun; Choi, Soon Chul

    2005-01-01

    Recently implant has become an important field in dental clinic. Radiographic examination of pre- and post-operation is essential for successful treatment. Clinicians should have knowledge about the purpose of the radiographic examination, suitable imaging modality for the cases, anatomic landmarks of tooth and jaw bone, advantage and limitation of panoramic radiographic examination for implant, principle and interpretation of cross-sectional imaging, bone mineral density, post-operative radiographic examination. This paper will be helpful to get above information for dentists who want to do dental implant successfully.

  20. Automating the radiographic NDT process

    International Nuclear Information System (INIS)

    Aman, J.K.

    1986-01-01

    Automation, the removal of the human element in inspection, has not been generally applied to film radiographic NDT. The justication for automating is not only productivity but also reliability of results. Film remains in the automated system of the future because of its extremely high image content, approximately 8 x 10 9 bits per 14 x 17. The equivalent to 2200 computer floppy discs. Parts handling systems and robotics applied for manufacturing and some NDT modalities, should now be applied to film radiographic NDT systems. Automatic film handling can be achieved with the daylight NDT film handling system. Automatic film processing is becoming the standard in industry and can be coupled to the daylight system. Robots offer the opportunity to automate fully the exposure step. Finally, computer aided interpretation appears on the horizon. A unit which laser scans a 14 x 17 (inch) film in 6 - 8 seconds can digitize film information for further manipulation and possible automatic interrogations (computer aided interpretation). The system called FDRS (for Film Digital Radiography System) is moving toward 50 micron (*approx* 16 lines/mm) resolution. This is believed to meet the need of the majority of image content needs. We expect the automated system to appear first in parts (modules) as certain operations are automated. The future will see it all come together in an automated film radiographic NDT system (author) [pt

  1. Evaluation of proximal caries in images resulting from different modes of radiographic digitalization.

    Science.gov (United States)

    Xavier, C R G; Araujo-Pires, Ana Claudia; Poleti, M L; Rubira-Bullen, I R F; Ferreira, O; Capelozza, A L A

    2011-09-01

    The aim of this study was to evaluate the performances of observers in diagnosing proximal caries in digital images obtained from digital bitewing radiographs using two scanners and four digital cameras in Joint Photographic Experts Group (JPEG) and tagged image file format (TIFF) files, and comparing them with the original conventional radiographs. In total, 56 extracted teeth were radiographed with Kodak Insight film (Eastman Kodak, Rochester, NY) in a Kaycor Yoshida X-ray device (Kaycor X-707; Yoshida Dental Manufacturing Co., Tokyo, Japan) operating at 70 kV and 7 mA with an exposure time of 0.40 s. The radiographs were obtained and scanned by CanonScan D646U (Canon USA Inc., Newport News, VA) and Genius ColorPage HR7X (KYE Systems Corp. America, Doral, FL) scanners, and by Canon Powershot G2 (Canon USA Inc.), Canon RebelXT (Canon USA Inc.), Nikon Coolpix 8700 (Nikon Inc., Melville, NY), and Nikon D70s (Nikon Inc.) digital cameras in JPEG and TIFF formats. Three observers evaluated the images. The teeth were then observed under the microscope in polarized light for the verification of the presence and depth of the carious lesions. The probability of no diagnosis ranged from 1.34% (Insight film) to 52.83% (CanonScan/JPEG). The sensitivity ranged from 0.24 (Canon RebelXT/JPEG) to 0.53 (Insight film), the specificity ranged from 0.93 (Nikon Coolpix/JPEG, Canon Powershot/TIFF, Canon RebelXT/JPEG and TIFF) to 0.97 (CanonScan/TIFF and JPEG) and the accuracy ranged from 0.82 (Canon RebelXT/JPEG) to 0.91 (CanonScan/JPEG). The carious lesion diagnosis did not change in either of the file formats (JPEG and TIFF) in which the images were saved for any of the equipment used. Only the CanonScan scanner did not have adequate performance in radiography digitalization for caries diagnosis and it is not recommended for this purpose.

  2. Detection for demineralization of dental hard tissues using index-sequenced radiographs

    International Nuclear Information System (INIS)

    Park, Dong Hyun; Park, Young Ho; Kim, Kyung Sook; Park, Jeong Hoon; Lee, Gi Ja; Choi, Sam Jin; Park, Hun Kuk; Choi, Yong Suk; Hwang, Eui Hwan

    2009-01-01

    The purpose of this study was to develop the radiographic technique for detecting the demineralization which is known as indication of dental caries. This technique was based on the comparing of multiple radiographs which was irradiated by multiple X-ray spectra. For the meaningful comparing, the multiple radiographs were reconstructed to the dosimetrically consistent images using a standard material. The difference of resulting images of same target with multiple spectra represents the difference of response of material as regards the spectra. We have found about 10% of demineralization of dental hard tissues particularly in the proximal region through the analyzing of differences. Most intriguing thing in this investigation was that the method to analyze difference shows us to an anatomic structure of dental hard tissues even if absolute values of optical density were excluded during the procedures.

  3. Detection for demineralization of dental hard tissues using index-sequenced radiographs

    Energy Technology Data Exchange (ETDEWEB)

    Park, Dong Hyun; Park, Young Ho; Kim, Kyung Sook; Park, Jeong Hoon; Lee, Gi Ja; Choi, Sam Jin; Park, Hun Kuk [Department of Biomedical Engineering, School of Medicine, KyungHee University, Seoul (Korea, Republic of); Choi, Yong Suk; Hwang, Eui Hwan [Department of Oral and Maxillofacial Radiology, Institute of Oral Biology, School of Dentistry, KyungHee University, Seoul (Korea, Republic of)

    2009-06-15

    The purpose of this study was to develop the radiographic technique for detecting the demineralization which is known as indication of dental caries. This technique was based on the comparing of multiple radiographs which was irradiated by multiple X-ray spectra. For the meaningful comparing, the multiple radiographs were reconstructed to the dosimetrically consistent images using a standard material. The difference of resulting images of same target with multiple spectra represents the difference of response of material as regards the spectra. We have found about 10% of demineralization of dental hard tissues particularly in the proximal region through the analyzing of differences. Most intriguing thing in this investigation was that the method to analyze difference shows us to an anatomic structure of dental hard tissues even if absolute values of optical density were excluded during the procedures.

  4. The effect of personalized versus standard patient protocols for radiostereometric analysis (RSA).

    Science.gov (United States)

    Muharemovic, O; Troelsen, A; Thomsen, M G; Kallemose, T; Gosvig, K K

    2018-05-01

    Increasing pressure in the clinic requires a more standardized approach to radiostereometric analysis (RSA) imaging. The aim of this study was to investigate whether implementation of personalized RSA patient protocols could increase image quality and decrease examination time and the number of exposure repetitions. Forty patients undergoing primary total hip arthroplasty were equally randomized to either a case or a control group. Radiographers in the case group were assisted by personalized patient protocols containing information about each patient's post-operative RSA imaging. Radiographers in the control group used a standard RSA protocol. At three months, radiographers in the case group significantly reduced (p RSA patient protocols have a positive effect on image quality and radiation dose savings. Implementation of personal patient protocols as a RSA standard will contribute to the reduction of examination time, thus ensuring a cost benefit for department and patient safety. Copyright © 2017 The College of Radiographers. Published by Elsevier Ltd. All rights reserved.

  5. Collaboration between radiological technologists (radiographers) and junior doctors during image interpretation improves the accuracy of diagnostic decisions

    International Nuclear Information System (INIS)

    Kelly, B.S.; Rainford, L.A.; Gray, J.; McEntee, M.F.

    2012-01-01

    Rationale and Objectives: In Emergency Departments (ED) junior doctors regularly make diagnostic decisions based on radiographic images. This study investigates whether collaboration between junior doctors and radiographers impacts on diagnostic accuracy. Materials and Methods: Research was carried out in the ED of a university teaching hospital and included 10 pairs of participants. Radiographers and junior doctors were shown 42 wrist radiographs and 40 CT Brains and were asked for their level of confidence of the presence or absence of distal radius fractures or fresh intracranial bleeds respectively using ViewDEX software, first working alone and then in pairs. Receiver Operating Characteristic was used to analyze performance. Results were compared using one-way analysis of variance. Results: The results showed statistically significant improvements in the Area Under the Curve (AUC) of the junior doctors when working with the radiographers for both sets of images (wrist and CT) treated as random readers and cases (p ≤ 0.008 and p ≤ 0.0026 respectively). While the radiographers’ results saw no significant changes, their mean Az values did show an increasing trend when working in collaboration. Conclusion: Improvement in performance of junior doctors following collaboration strongly suggests changes in the potential to improve accuracy of patient diagnosis and therefore patient care. Further training for junior doctors in the interpretation of diagnostic images should also be considered. Decision making of junior doctors was positively impacted on after introducing the opinion of a radiographer. Collaboration exceeds the sum of the parts; the two professions are better together.

  6. Artificial intelligence for analyzing orthopedic trauma radiographs.

    Science.gov (United States)

    Olczak, Jakub; Fahlberg, Niklas; Maki, Atsuto; Razavian, Ali Sharif; Jilert, Anthony; Stark, André; Sköldenberg, Olof; Gordon, Max

    2017-12-01

    Background and purpose - Recent advances in artificial intelligence (deep learning) have shown remarkable performance in classifying non-medical images, and the technology is believed to be the next technological revolution. So far it has never been applied in an orthopedic setting, and in this study we sought to determine the feasibility of using deep learning for skeletal radiographs. Methods - We extracted 256,000 wrist, hand, and ankle radiographs from Danderyd's Hospital and identified 4 classes: fracture, laterality, body part, and exam view. We then selected 5 openly available deep learning networks that were adapted for these images. The most accurate network was benchmarked against a gold standard for fractures. We furthermore compared the network's performance with 2 senior orthopedic surgeons who reviewed images at the same resolution as the network. Results - All networks exhibited an accuracy of at least 90% when identifying laterality, body part, and exam view. The final accuracy for fractures was estimated at 83% for the best performing network. The network performed similarly to senior orthopedic surgeons when presented with images at the same resolution as the network. The 2 reviewer Cohen's kappa under these conditions was 0.76. Interpretation - This study supports the use for orthopedic radiographs of artificial intelligence, which can perform at a human level. While current implementation lacks important features that surgeons require, e.g. risk of dislocation, classifications, measurements, and combining multiple exam views, these problems have technical solutions that are waiting to be implemented for orthopedics.

  7. Usefulness of computerized method for lung nodule detection on digital chest radiographs using similar subtraction images from different patients

    International Nuclear Information System (INIS)

    Aoki, Takatoshi; Oda, Nobuhiro; Yamashita, Yoshiko; Yamamoto, Keiji; Korogi, Yukunori

    2012-01-01

    Purpose: The purpose of this study is to evaluate the usefulness of a novel computerized method to select automatically the similar chest radiograph for image subtraction in the patients who have no previous chest radiographs and to assist the radiologists’ interpretation by presenting the “similar subtraction image” from different patients. Materials and methods: Institutional review board approval was obtained, and the requirement for informed patient consent was waived. A large database of approximately 15,000 normal chest radiographs was used for searching similar images of different patients. One hundred images of candidates were selected according to two clinical parameters and similarity of the lung field in the target image. We used the correlation value of chest region in the 100 images for searching the most similar image. The similar subtraction images were obtained by subtracting the similar image selected from the target image. Thirty cases with lung nodules and 30 cases without lung nodules were used for an observer performance test. Four attending radiologists and four radiology residents participated in this observer performance test. Results: The AUC for all radiologists increased significantly from 0.925 to 0.974 with the CAD (P = .004). When the computer output images were available, the average AUC for the residents was more improved (0.960 vs. 0.890) than for the attending radiologists (0.987 vs. 0.960). Conclusion: The novel computerized method for lung nodule detection using similar subtraction images from different patients would be useful to detect lung nodules on digital chest radiographs, especially for less experienced readers.

  8. Are radiographs needed when MR imaging is performed for non-acute knee symptoms in patients younger than 45 years of age?

    International Nuclear Information System (INIS)

    Braak, Bert P.M. ter; Vincken, Patrice W.J.; Erkel, Arian R. van; Bloem, Johan L.; Bloem, Rolf M.; Napoleon, L.J.; Coene, M.N.; Luijt, Peter A. van; Lange, Sam de

    2007-01-01

    The objective was to determine the value of radiographs in young adults with non-acute knee symptoms who are scheduled for magnetic resonance imaging (MRI). Nine hundred and sixty-one consecutive patients aged between 16 and 45 years with knee symptoms of at least 4 weeks' duration were prospectively included in three participating hospitals. After applying exclusion criteria, 798 patients remained. Exclusion criteria were previous knee surgery (including arthroscopy) or MRI, history of rheumatoid arthritis, clinical diagnosis of retropatellar chondromalacia, contra-indication for MRI and recent trauma. We identified two groups: group A with no history of trauma (n = 332), and group B with an old (>4 weeks) history of trauma (n = 466). Patients had a standardized history taken, and underwent a physical exam, antero-posterior (AP) and lateral radiographs and MRI. We evaluated the radiographs and MRI for osseous lesions, articular surface lesions, fractures, osteoarthritis, loose bodies, bone marrow edema and incidental findings. Subsequently, patients with osseous abnormalities (Kellgren grade 1 and 2 excluded) on radiographs and a matched control group was evaluated again using MRI without radiographs. Median duration of symptoms was 20 weeks. In group A, radiographs showed 36 osseous abnormalities in 332 patients (10.8%). Only 13 of these, all Kellgren grade 1 osteoarthritis, were not confirmed on MRI. MRI showed 72 (21.7%) additional abnormalities not confirmed on radiographs. In group B, radiographs showed 40 osseous abnormalities (8.6%) in 466 patients. Only 15 of these, all Kellgren grade 1 osteoarthritis, were not confirmed on MRI. MRI showed 194 (41.6%) additional abnormalities not confirmed on radiographs. The second evaluation of MRI without radiographs in 34 patients was identical to the first MRI evaluation. Common lesions were significantly more often diagnosed with MRI than with radiographs. Radiographs should not be obtained routinely when MRI is

  9. Are radiographs needed when MR imaging is performed for non-acute knee symptoms in patients younger than 45 years of age?

    Energy Technology Data Exchange (ETDEWEB)

    Braak, Bert P.M. ter; Vincken, Patrice W.J.; Erkel, Arian R. van; Bloem, Johan L. [Leiden University Medical Center, Department of Radiology, P.O. Box 9600, Leiden (Netherlands); Bloem, Rolf M. [Leiden University Medical Center, Department of Orthopaedic Surgery, Leiden (Netherlands); Napoleon, L.J.; Coene, M.N. [HAGA Hospital, Department of Orthopaedic Surgery, The Hague (Netherlands); Luijt, Peter A. van [Leiden University Medical Center, Department of Traumatology, Leiden (Netherlands); Lange, Sam de [Medical Center Haaglanden, Department of Orthopaedic Surgery, The Hague (Netherlands); Department of Orthopaedic Surgery, Delft (Netherlands)

    2007-12-15

    The objective was to determine the value of radiographs in young adults with non-acute knee symptoms who are scheduled for magnetic resonance imaging (MRI). Nine hundred and sixty-one consecutive patients aged between 16 and 45 years with knee symptoms of at least 4 weeks' duration were prospectively included in three participating hospitals. After applying exclusion criteria, 798 patients remained. Exclusion criteria were previous knee surgery (including arthroscopy) or MRI, history of rheumatoid arthritis, clinical diagnosis of retropatellar chondromalacia, contra-indication for MRI and recent trauma. We identified two groups: group A with no history of trauma (n = 332), and group B with an old (>4 weeks) history of trauma (n = 466). Patients had a standardized history taken, and underwent a physical exam, antero-posterior (AP) and lateral radiographs and MRI. We evaluated the radiographs and MRI for osseous lesions, articular surface lesions, fractures, osteoarthritis, loose bodies, bone marrow edema and incidental findings. Subsequently, patients with osseous abnormalities (Kellgren grade 1 and 2 excluded) on radiographs and a matched control group was evaluated again using MRI without radiographs. Median duration of symptoms was 20 weeks. In group A, radiographs showed 36 osseous abnormalities in 332 patients (10.8%). Only 13 of these, all Kellgren grade 1 osteoarthritis, were not confirmed on MRI. MRI showed 72 (21.7%) additional abnormalities not confirmed on radiographs. In group B, radiographs showed 40 osseous abnormalities (8.6%) in 466 patients. Only 15 of these, all Kellgren grade 1 osteoarthritis, were not confirmed on MRI. MRI showed 194 (41.6%) additional abnormalities not confirmed on radiographs. The second evaluation of MRI without radiographs in 34 patients was identical to the first MRI evaluation. Common lesions were significantly more often diagnosed with MRI than with radiographs. Radiographs should not be obtained routinely when MRI is

  10. Active filtering applied to radiographic images unfolded by the Richardson-Lucy algorithm

    International Nuclear Information System (INIS)

    Almeida, Gevaldo L. de; Silvani, Maria Ines; Lopes, Ricardo T.

    2011-01-01

    Degradation of images caused by systematic uncertainties can be reduced when one knows the features of the spoiling agent. Typical uncertainties of this kind arise in radiographic images due to the non - zero resolution of the detector used to acquire them, and from the non-punctual character of the source employed in the acquisition, or from the beam divergence when extended sources are used. Both features blur the image, which, instead of a single point exhibits a spot with a vanishing edge, reproducing hence the point spread function - PSF of the system. Once this spoiling function is known, an inverse problem approach, involving inversion of matrices, can then be used to retrieve the original image. As these matrices are generally ill-conditioned, due to statistical fluctuation and truncation errors, iterative procedures should be applied, such as the Richardson-Lucy algorithm. This algorithm has been applied in this work to unfold radiographic images acquired by transmission of thermal neutrons and gamma-rays. After this procedure, the resulting images undergo an active filtering which fairly improves their final quality at a negligible cost in terms of processing time. The filter ruling the process is based on the matrix of the correction factors for the last iteration of the deconvolution procedure. Synthetic images degraded with a known PSF, and undergone to the same treatment, have been used as benchmark to evaluate the soundness of the developed active filtering procedure. The deconvolution and filtering algorithms have been incorporated to a Fortran program, written to deal with real images, generate the synthetic ones and display both. (author)

  11. Radiographic enhancement and analysis system

    International Nuclear Information System (INIS)

    Schlosser, M.S.

    1981-01-01

    Radiographic image enhancement and analysis techniques are discussed as they apply to nondestructive inspection. A system is described which has been developed to enhance and quantitatively evaluate radiographic images using digital computer techniques. Some examples of typical applications are also presented as an introduction to this new inspection technique. (author)

  12. CEC quality criteria for diagnostic radiographic images and patient exposure trial

    International Nuclear Information System (INIS)

    Nahrstedt, U.; Wall, B.; Maccia, C.; Moores, B.M.; Padovani, R.

    1990-01-01

    The intention of this report has been to present the results of a multinational trial set up by a study group of the radiation protection programme of the CEC. In view of proceeding towards the harmonization and the optimization of the radiological techniques commonly used in different European countries, the relevance of quality criteria for radiographic images together with dose requirements were checked on about 900 examined patients. Due to the type of X-ray projections considered, more than 1 200 questionnaires concerning the real X-ray films were therefore collected and evaluated through a scoring system. Such an approach was relevant and contributed to providing practical considerations on how to reduce and optimize patient received dose while keeping the essential medical information imaged on the film. Indeed the results obtained allowed identification of technical modalities corresponding to that objective. Furthermore, analysis of results revealed two main areas which should be further taken into consideration: - personnel training in radiation protection (radiologists and radiographers), establishment of quality assurance programmes in diagnostic radiology (good usage of radiological equipment and reduction of wasted films)

  13. Quantitative analysis of bowel gas by plain abdominal radiograph combined with computer image processing

    International Nuclear Information System (INIS)

    Gao Yan; Peng Kewen; Zhang Houde; Shen Bixian; Xiao Hanxin; Cai Juan

    2003-01-01

    Objective: To establish a method for quantitative analysis of bowel gas by plain abdominal radiograph and computer graphics. Methods: Plain abdominal radiographs in supine position from 25 patients with irritable bowel syndrome (IBS) and 20 health controls were studied. A gastroenterologist and a radiologist independently conducted the following procedure on each radiograph. After the outline of bowel gas was traced by axe pen, the radiograph was digitized by a digital camera and transmitted to the computer with Histogram software. The total gas area was determined as the pixel value on images. The ratio of the bowel gas quantity to the pixel value in the region surrounded by a horizontal line tangential to the superior pubic symphysis margin, a horizontal line tangential to the tenth dorsal vertebra inferior margin, and the lateral line tangential to the right and left anteriosuperior iliac crest, was defined as the gas volume score (GVS). To examine the sequential reproducibility, a second plain abdominal radiograph was performed in 5 normal controls 1 week later, and the GVS were compared. Results: Bowel gas was easily identified on the plain abdominal radiograph. Both large and small intestine located in the selected region. Both observers could finish one radiographic measurement in less than 10 mins. The correlation coefficient between the two observers was 0.986. There was no statistical difference on GVS between the two sequential radiographs in 5 health controls. Conclusion: Quantification of bowel gas based on plain abdominal radiograph and computer is simple, rapid, and reliable

  14. Radiographic constant exposure technique

    DEFF Research Database (Denmark)

    Domanus, Joseph Czeslaw

    1985-01-01

    The constant exposure technique has been applied to assess various industrial radiographic systems. Different X-ray films and radiographic papers of two producers were compared. Special attention was given to fast film and paper used with fluorometallic screens. Radiographic image quality...... was tested by the use of ISO wire IQI's and ASTM penetrameters used on Al and Fe test plates. Relative speed and reduction of kilovoltage obtained with the constant exposure technique were calculated. The advantages of fast radiographic systems are pointed out...

  15. A survey to assess audit mechanisms practised by skeletal reporting radiographers

    International Nuclear Information System (INIS)

    Jones, H.C.; Manning, D.

    2008-01-01

    Purpose: This study investigates the role of plain film reporting radiographers and the methods they employ to evaluate the quality of their performance. Method: The survey was conducted in 2003. Questionnaires were sent, via the universities, to radiographers who had registered on a post-graduate musculoskeletal image interpretation course at a University in England since their introduction (9 years earlier). Results: The response rate was 37% (n = 112). Sixty-four percent of the trained reporting radiographers surveyed are creating independent reports on musculoskeletal images and an additional 15% contribute to a double reporting system. Twenty-one percent of the reporting radiographers in this study are not undertaking audit of their practice. Of the 79% who are participating in audit programmes the variety of methods being used are widespread. In order to protect against litigation, 19% of reporting radiographers have a portfolio of evidence supporting their competency; 71% have a specific job description for their advanced role; 73% of reporting radiographers are members of a trade union; and 82% of reporting radiographers work to a departmental protocol. Conclusion: The majority of reporting radiographers are participating in some form of audit. However, it is imperative that the sizeable minority who are not should initiate this process promptly. It is important that national standards are set so that these audit processes become embedded into practice for the protection of both the patient and radiographer. The inconsistency shown with regard to audit processes and protection against litigation suggests that further clarification is required from the professional bodies

  16. A survey to assess audit mechanisms practised by skeletal reporting radiographers

    Energy Technology Data Exchange (ETDEWEB)

    Jones, H.C. [Directorate of Radiology, Royal Liverpool University Hospital Trust, Prescot Street, Liverpool L7 8XP (United Kingdom)], E-mail: helen.jones@rlbuht.nhs.uk; Manning, D. [School of Medical Imaging Sciences, St. Martin' s College, Lancaster LA1 3JD (United Kingdom)

    2008-08-15

    Purpose: This study investigates the role of plain film reporting radiographers and the methods they employ to evaluate the quality of their performance. Method: The survey was conducted in 2003. Questionnaires were sent, via the universities, to radiographers who had registered on a post-graduate musculoskeletal image interpretation course at a University in England since their introduction (9 years earlier). Results: The response rate was 37% (n = 112). Sixty-four percent of the trained reporting radiographers surveyed are creating independent reports on musculoskeletal images and an additional 15% contribute to a double reporting system. Twenty-one percent of the reporting radiographers in this study are not undertaking audit of their practice. Of the 79% who are participating in audit programmes the variety of methods being used are widespread. In order to protect against litigation, 19% of reporting radiographers have a portfolio of evidence supporting their competency; 71% have a specific job description for their advanced role; 73% of reporting radiographers are members of a trade union; and 82% of reporting radiographers work to a departmental protocol. Conclusion: The majority of reporting radiographers are participating in some form of audit. However, it is imperative that the sizeable minority who are not should initiate this process promptly. It is important that national standards are set so that these audit processes become embedded into practice for the protection of both the patient and radiographer. The inconsistency shown with regard to audit processes and protection against litigation suggests that further clarification is required from the professional bodies.

  17. Comparison of Lumbar Lordosis in Lateral Radiographs in Standing Position with supine MR Imaging in consideration of the Sacral Slope.

    Science.gov (United States)

    Benditz, Achim; Boluki, Daniel; Weber, Markus; Zeman, Florian; Grifka, Joachim; Völlner, Florian

    2017-03-01

    Purpose  To investigate the influence of sacral slope on the correlation between measurements of lumbar lordosis obtained by standing radiographs and magnetic resonance images in supine position (MRI). Little information is available on the correlation between measurements of lumbar lordosis obtained by radiographic and MR images. Most relevant studies have shown correlations for the thoracic spine, but detailed analyses on the lumbar spine are lacking. Methods  MR images and standing lateral radiographs of 63 patients without actual low back pain or radiographic pathologies of the lumbar spine were analyzed. Standing radiographic measurements included the sagittal parameters pelvic incidence (PI) pelvic tilt (PT), and sacral slope (SS); MR images were used to additionally measure lumbar L1-S1 lordosis and single level lordosis. Differences between radiographic and MRI measurements were analyzed and divided into 4 subgroups of different sacral slope according to Roussouly's classification. Results  Global lumbar lordosis (L1-S1) was 44.99° (± 10 754) on radiographs and 47.91° (± 9.170) on MRI, yielding a clinically relevant correlation (r = 0.61, p lordosis only showed minor differences. At all levels except for L5 / S1, lordosis measured by means of standing radiographs was higher than that measured by MRI. The difference in global lumbar L1-S1 lordosis was -2.9°. Analysis of the Roussouly groups showed the largest difference for L1-S1 (-8.3°) in group 2. In group 4, when measured on MRI, L5 / S1 lordosis (25.71°) was lower than L4 / L5 lordosis (27.63°) compared to the other groups. Conclusions  Although measurements of global lumbar lordosis significantly differed between the two scanning technologies, the mean difference was just 2.9°. MRI in supine position may be used for estimating global lumbar lordosis, but single level lordosis should be determined by means of standing radiographs. Key Points   · Large

  18. Attitudes of radiographers to radiographer-led discharge: A survey

    International Nuclear Information System (INIS)

    Lumsden, Laura; Cosson, Philip

    2015-01-01

    Background: The traditional role of the Diagnostic Radiographer in image acquisition has gradually been extended through skill-mix, particularly to include abnormality detection. Aims: This research focused on the attitudes of Radiographers to Radiographer-led Discharge (RLD), where Radiographers discharge patients with minor injuries and perform tasks previously undertaken by Accident and Emergency staff. The effects of job role, hospital type, experience and whether RLD was used in the participant's trust were examined. Method: A multiple-indicator online questionnaire assessed attitudes to RLD. Snowball sampling was used with advertisement via emails, posters and cards, containing Quick Response (QR) codes. Statement responses were coded, with reverse coding for negative statements and total scores were calculated. A higher score represented a more positive attitude. Results: 101 questionnaires were completed (an estimated 30% response rate) and the mean total score was 84/115. 95% of participants supported radiographer involvement in abnormality detection, with 46.5% selecting RLD as the preferred system for minor injuries patients vs 48.5% preferring commenting alone. Discussion: Participants were positive about extending their role through RLD and felt confident in their image interpretation abilities, though expressed concern for the legal consequences of the role and adequate pay. Generalization of the results is limited due to the possible low response rate. Conclusion: Overall, participants demonstrated positive attitudes towards RLD but they also indicate the need for appropriate payment for any additional responsibility. These findings are promising for successful implementation of RLD, though larger-scale research including radiologists, business managers, A and E staff and patients would be beneficial. - Highlights: • 101 questionnaires were completed (an estimated 30% response rate). • 95% of participants supported radiographer involvement

  19. Teleradiology in a neonatal intensive care unit: Comparison between the interpretation of transmitted digital images and film radiographs

    International Nuclear Information System (INIS)

    McFee, W.H.; Bramson, R.T.; Cates, J.D.; Curran, J.S.

    1987-01-01

    Using a Raytel teleradiology system, a prospective comparison was made between the interpretations of 700 transmitted digital images and the film radiographs from which these digital images were made. The original films consisted of all of the radiographs obtained from the infants in a 40-bed level III neonatal intensive care unit over a 6-week period. Interpretations were done by two radiologists, initially from transmitted images and subsequently from the original films. Comparison of the interpretations demonstrates a remarkably high degree of correlation, with less than 0.5% clinically significant discrepancies reported

  20. Magnetic resonance imaging of osteonecrosis in divers: comparison with plain radiographs

    International Nuclear Information System (INIS)

    Shinoda, S.; Hasegawa, Y.; Kawasaki, S.; Tagawa, N.; Iwata, H.

    1997-01-01

    Objective. To assess the diagnostic value of magnetic resonance imaging (MRI) as compared with radiographic findings in osteonecrosis in divers. Design and patients. MRI scans and conventional radiographs of the shoulder, hip and knee joints of 23 professional male scuba divers were reviewed together with their clinical findings and personal histories. Correlations between the MRI findings and the radiographic evaluation, clinical symptoms, and personal history were then investigated. Results and conclusions. Lesions found on MRI in 23 divers included 27 in 39 proximal humeri, 17 in 36 proximal femora, 13 in 32 distal femora, and 12 in 32 proximal tibiae. Diffuse, marginated, or irregular patterns were observed. No lesions were seen in epiphyses of the distal femur or proximal tibia. We tried to classify these MRI findings by location and appearance. MRI showed no patients with only one affected bone. A close correlation between the MRI findings and maximum diving depth was observed in the proximal humerus. MRI depicted bone lesions that could not be detected on the radiographs. A routine MRI investigation of the hip joints should be performed in every diver in whom osteonecrosis is diagnosed at another site, for early detection of femoral head osteonecrosis. MRI of the shoulder joint is also the best surveillance in divers who dive deeper than 15 m. (orig.). With 4 figs., 5 tabs

  1. Optimizing radiation exposure for CT localizer radiographs

    Energy Technology Data Exchange (ETDEWEB)

    Bohrer, Evelyn; Maeder, Ulf; Fiebich, Martin [Univ. of Applied Sciences, Giessen (Germany). Inst. of Medical Physics and Radiation Protection-IMPS; Schaefer, Stefan; Krombach, Gabriele A. [Univ. Hospital Giessen (Germany). Dept. of Radiology; Noel, Peter B. [Technische Univ. Muenchen (Germany). Dept. of Diagnostic and Interventional Radiology

    2017-08-01

    The trend towards submillisievert CT scans leads to a higher dose fraction of localizer radiographs in CT examinations. The already existing technical capabilities make dose optimization of localizer radiographs worthwhile. Modern CT scanners apply automatic exposure control (AEC) based on attenuation data in such a localizer. Therefore not only this aspect but also the detectability of anatomical landmarks in the localizer for the desired CT scan range adjustment needs to be considered. The effective dose of a head, chest, and abdomen-pelvis localizer radiograph with standard factory settings and user-optimized settings was determined using Monte Carlo simulations. CT examinations of an anthropomorphic phantom were performed using multiple sets of acquisition parameters for the localizer radiograph and the AEC for the subsequent helical CT scan. Anatomical landmarks were defined to assess the image quality of the localizer. CTDI{sub vol} and effective mAs per slice of the helical CT scan were recorded to examine the impact of localizer settings on a helical CT scan. The dose of the localizer radiograph could be decreased by more than 90% while the image quality remained sufficient when selecting the lowest available settings (80 kVp, 20 mA, pa tube position). The tube position during localizer acquisition had a greater impact on the AEC than the reduction of tube voltage and tube current. Except for the use of a pa tube position, all changes of acquisition parameters for the localizer resulted in a decreased total radiation exposure. A dose reduction of CT localizer radiograph is necessary and possible. In the examined CT system there was no negative impact on the modulated helical CT scan when the lowest tube voltage and tube current were used for the localizer.

  2. Image processing in digital chest radiography

    International Nuclear Information System (INIS)

    Manninen, H.; Partanen, K.; Lehtovirta, J.; Matsi, P.; Soimakallio, S.

    1992-01-01

    The usefulness of digital image processing of chest radiographs was evaluated in a clinical study. In 54 patients, chest radiographs in the posteroanterior projection were obtained by both 14 inch digital image intensifier equipment and the conventional screen-film technique. The digital radiographs (512x512 image format) viewed on a 625 line monitor were processed in 3 different ways: 1.standard display; 2.digital edge enhancement for the standard display; 3.inverse intensity display. The radiographs were interpreted independently by 3 radiologists. Diagnoses were confirmed by CT, follow-up radiographs and clinical records. Chest abnormalities of the films analyzed included 21 primary lung tumors, 44 pulmonary nodules, 16 cases with mediastinal disease, 17 with pneumonia /atelectasis. Interstitial lung disease, pleural plaques, and pulmonary emphysema were found in 30, 18 and 19 cases respectively. Sensitivity of conventional radiography when averaged overall findings was better than that of digital techniques (P<0.001). Differences in diagnostic accuracy measured by sensitivity and specificity between the 3 digital display modes were small. Standard image display showed better sensitivity for pulmonary nodules (0.74 vs 0.66; P<0.05) but poorer specificity for pulmonary emphysema (0.85 vs 0.93; P<0.05) compared with inverse intensity display. It is concluded that when using 512x512 image format, the routine use of digital edge enhancement and tone reversal at digital chest radiographs is not warranted. (author). 12 refs.; 4 figs.; 2 tabs

  3. Computer-aided Detection Fidelity of Pulmonary Nodules in Chest Radiograph

    Directory of Open Access Journals (Sweden)

    Nikolaos Dellios

    2017-01-01

    Full Text Available Aim: The most ubiquitous chest diagnostic method is the chest radiograph. A common radiographic finding, quite often incidental, is the nodular pulmonary lesion. The detection of small lesions out of complex parenchymal structure is a daily clinical challenge. In this study, we investigate the efficacy of the computer-aided detection (CAD software package SoftView™ 2.4A for bone suppression and OnGuard™ 5.2 (Riverain Technologies, Miamisburg, OH, USA for automated detection of pulmonary nodules in chest radiographs. Subjects and Methods: We retrospectively evaluated a dataset of 100 posteroanterior chest radiographs with pulmonary nodular lesions ranging from 5 to 85 mm. All nodules were confirmed with a consecutive computed tomography scan and histologically classified as 75% malignant. The number of detected lesions by observation in unprocessed images was compared to the number and dignity of CAD-detected lesions in bone-suppressed images (BSIs. Results: SoftView™ BSI does not affect the objective lesion-to-background contrast. OnGuard™ has a stand-alone sensitivity of 62% and specificity of 58% for nodular lesion detection in chest radiographs. The false positive rate is 0.88/image and the false negative (FN rate is 0.35/image. From the true positive lesions, 20% were proven benign and 80% were malignant. FN lesions were 47% benign and 53% malignant. Conclusion: We conclude that CAD does not qualify for a stand-alone standard of diagnosis. The use of CAD accompanied with a critical radiological assessment of the software suggested pattern appears more realistic. Accordingly, it is essential to focus on studies assessing the quality-time-cost profile of real-time (as opposed to retrospective CAD implementation in clinical diagnostics.

  4. Radiographic image quality and dose at thorax, abdomen and skull of patients at HC-FMB-UNESP

    International Nuclear Information System (INIS)

    Alvarez, Matheus; Giacomini, Guilherme; Bacchim Neto, Fernando A.; Alves, Allan F.F.; Velo, Alexandre F.; Miranda, Jose R.A.; Pina, Diana R. de

    2013-01-01

    ICRP 103 specifies reference dose levels to be used during radiographic exams. Usually, the radiographer qualitative determines the best radiographic technique (kV and mAs) in order to obtain better image quality with the lowest dose. The objective of this study was to evaluate the doses used in examination of the chest, abdomen and skull in patients of different physical sizes, and infer about the amount of dose required to maintain acceptable radiological contrast in patients of different physical sizes. Techniques used by experienced radiographers of HC-FMB-UNESP for examinations of the chest (PA), abdomen (AP) and skull (AP) for patients of different thickness (small, medium and thick body) were obtained. Dose measurements were performed referring to all kV/mAs combinations. PMMA phantoms were placed below the ionization chamber. The Signal Difference Noise Ratio (SDNR) of the images of the phantoms were calculated from an area of contrast and a region of normal tissue. The Figure of Merit (FoM) was calculated for each of the exam modality. Measured FoM decreased according to the thickness of the chest and abdomen, indicating the need to increase the dose level to maintain the same level of image contrast. Patients thicker usually end up getting more than twice the dose of lean patients. Required image quality levels for correct diagnosis should be obtained using dose levels as low as reasonably practicable examination. These factors highlight the need for a program of quality assurance and effective dose studies in actual service. (author)

  5. The x-ray light valve: A potentially low-cost, digital radiographic imaging system-concept and implementation considerations

    International Nuclear Information System (INIS)

    Webster, Christie Ann; Koprinarov, Ivaylo; Germann, Stephen; Rowlands, J. A.

    2008-01-01

    New x-ray radiographic systems based on large-area flat-panel technology have revolutionized our capability to produce digital x-ray images. However, these imagers are extraordinarily expensive compared to the systems they are replacing. Hence, there is a need for a low-cost digital imaging system for general applications in radiology. A novel potentially low-cost radiographic imaging system based on established technologies is proposed--the X-Ray Light Valve (XLV). This is a potentially high-quality digital x-ray detector made of a photoconducting layer and a liquid-crystal cell, physically coupled in a sandwich structure. Upon exposure to x rays, charge is collected on the surface of the photoconductor. This causes a change in the optical properties of the liquid-crystal cell and a visible image is generated. Subsequently, it is digitized by a scanned optical imager. The image formation is based on controlled modulation of light from an external source. The operation and practical implementation of the XLV system are described. The potential performance of the complete system and issues related to sensitivity, spatial resolution, noise, and speed are discussed. The feasibility of clinical use of an XLV device based on amorphous selenium (a-Se) as the photoconductor and a reflective electrically controlled birefringence cell is analyzed. The results of our analysis indicate that the XLV can potentially be adapted to a wide variety of radiographic tasks

  6. JJ1017 committee report: image examination order codes--standardized codes for imaging modality, region, and direction with local expansion: an extension of DICOM.

    Science.gov (United States)

    Kimura, Michio; Kuranishi, Makoto; Sukenobu, Yoshiharu; Watanabe, Hiroki; Tani, Shigeki; Sakusabe, Takaya; Nakajima, Takashi; Morimura, Shinya; Kabata, Shun

    2002-06-01

    The digital imaging and communications in medicine (DICOM) standard includes parts regarding nonimage data information, such as image study ordering data and performed procedure data, and is used for sharing information between HIS/RIS and modality systems, which is essential for IHE. To bring such parts of the DICOM standard into force in Japan, a joint committee of JIRA and JAHIS established the JJ1017 management guideline, specifying, for example, which items are legally required in Japan, while remaining optional in the DICOM standard. In Japan, the contents of orders from referring physicians for radiographic examinations include details of the examination. Such details are not used typically by referring physicians requesting radiographic examinations in the United States, because radiologists in the United States often determine the examination protocol. The DICOM standard has code tables for examination type, region, and direction for image examination orders. However, this investigation found that it does not include items that are detailed sufficiently for use in Japan, because of the above-mentioned reason. To overcome these drawbacks, we have generated the JJ1017 code for these 3 codes for use based on the JJ1017 guidelines. This report introduces the JJ1017 code. These codes (the study type codes in particular) must be expandable to keep up with technical advances in equipment. Expansion has 2 directions: width for covering more categories and depth for specifying the information in more detail (finer categories). The JJ1017 code takes these requirements into consideration and clearly distinguishes between the stem part as the common term and the expansion. The stem part of the JJ1017 code partially utilizes the DICOM codes to remain in line with the DICOM standard. This work is an example of how local requirements can be met by using the DICOM standard and extending it.

  7. A Comparative Study on Diagnostic Accuracy of Colour Coded Digital Images, Direct Digital Images and Conventional Radiographs for Periapical Lesions – An In Vitro Study

    Science.gov (United States)

    Mubeen; K.R., Vijayalakshmi; Bhuyan, Sanat Kumar; Panigrahi, Rajat G; Priyadarshini, Smita R; Misra, Satyaranjan; Singh, Chandravir

    2014-01-01

    Objectives: The identification and radiographic interpretation of periapical bone lesions is important for accurate diagnosis and treatment. The present study was undertaken to study the feasibility and diagnostic accuracy of colour coded digital radiographs in terms of presence and size of lesion and to compare the diagnostic accuracy of colour coded digital images with direct digital images and conventional radiographs for assessing periapical lesions. Materials and Methods: Sixty human dry cadaver hemimandibles were obtained and periapical lesions were created in first and second premolar teeth at the junction of cancellous and cortical bone using a micromotor handpiece and carbide burs of sizes 2, 4 and 6. After each successive use of round burs, a conventional, RVG and colour coded image was taken for each specimen. All the images were evaluated by three observers. The diagnostic accuracy for each bur and image mode was calculated statistically. Results: Our results showed good interobserver (kappa > 0.61) agreement for the different radiographic techniques and for the different bur sizes. Conventional Radiography outperformed Digital Radiography in diagnosing periapical lesions made with Size two bur. Both were equally diagnostic for lesions made with larger bur sizes. Colour coding method was least accurate among all the techniques. Conclusion: Conventional radiography traditionally forms the backbone in the diagnosis, treatment planning and follow-up of periapical lesions. Direct digital imaging is an efficient technique, in diagnostic sense. Colour coding of digital radiography was feasible but less accurate however, this imaging technique, like any other, needs to be studied continuously with the emphasis on safety of patients and diagnostic quality of images. PMID:25584318

  8. Comparison of lumbar lordosis in lateral radiographs in standing position with supine MR imaging in consideration of the sacral slope

    International Nuclear Information System (INIS)

    Benditz, Achim; Boluki, Daniel; Weber, Markus; Grifka, Joachim; Voellner, Florian; Zeman, Florian

    2017-01-01

    To investigate the influence of sacral slope on the correlation between measurements of lumbar lordosis obtained by standing radiographs and magnetic resonance images in supine position (MRI). Little information is available on the correlation between measurements of lumbar lordosis obtained by radiographic and MR images. Most relevant studies have shown correlations for the thoracic spine, but detailed analyses on the lumbar spine are lacking. MR images and standing lateral radiographs of 63 patients without actual low back pain or radiographic pathologies of the lumbar spine were analyzed. Standing radiographic measurements included the sagittal parameters pelvic incidence (PI) pelvic tilt (PT), and sacral slope (SS); MR images were used to additionally measure lumbar L1-S1 lordosis and single level lordosis. Differences between radiographic and MRI measurements were analyzed and divided into 4 subgroups of different sacral slope according to Roussouly's classification. Global lumbar lordosis (L1-S1) was 44.99 (± 10754) on radiographs and 47.91 (±9.170) on MRI, yielding a clinically relevant correlation (r = 0.61, p < 0.01). Measurements of single level lordosis only showed minor differences. At all levels except for L5 / S1, lordosis measured by means of standing radiographs was higher than that measured by MRI. The difference in global lumbar L1-S1 lordosis was -2.9 . Analysis of the Roussouly groups showed the largest difference for L1-S1 (-8.3 ) in group 2. In group 4, when measured on MRI, L5 / S1 lordosis (25.71 ) was lower than L4 / L5 lordosis (27.63 ) compared to the other groups. Although measurements of global lumbar lordosis significantly differed between the two scanning technologies, the mean difference was just 2.9 . MRI in supine position may be used for estimating global lumbar lordosis, but single level lordosis should be determined by means of standing radiographs.

  9. Comparison of lumbar lordosis in lateral radiographs in standing position with supine MR imaging in consideration of the sacral slope

    Energy Technology Data Exchange (ETDEWEB)

    Benditz, Achim; Boluki, Daniel; Weber, Markus; Grifka, Joachim; Voellner, Florian [Regensburg Univ. Medical Center (Germany). Orthopedic Surgery; Zeman, Florian [Regensburg Univ. Medical Center (Germany). Center for Clinical Studies

    2017-03-15

    To investigate the influence of sacral slope on the correlation between measurements of lumbar lordosis obtained by standing radiographs and magnetic resonance images in supine position (MRI). Little information is available on the correlation between measurements of lumbar lordosis obtained by radiographic and MR images. Most relevant studies have shown correlations for the thoracic spine, but detailed analyses on the lumbar spine are lacking. MR images and standing lateral radiographs of 63 patients without actual low back pain or radiographic pathologies of the lumbar spine were analyzed. Standing radiographic measurements included the sagittal parameters pelvic incidence (PI) pelvic tilt (PT), and sacral slope (SS); MR images were used to additionally measure lumbar L1-S1 lordosis and single level lordosis. Differences between radiographic and MRI measurements were analyzed and divided into 4 subgroups of different sacral slope according to Roussouly's classification. Global lumbar lordosis (L1-S1) was 44.99 (± 10754) on radiographs and 47.91 (±9.170) on MRI, yielding a clinically relevant correlation (r = 0.61, p < 0.01). Measurements of single level lordosis only showed minor differences. At all levels except for L5 / S1, lordosis measured by means of standing radiographs was higher than that measured by MRI. The difference in global lumbar L1-S1 lordosis was -2.9 . Analysis of the Roussouly groups showed the largest difference for L1-S1 (-8.3 ) in group 2. In group 4, when measured on MRI, L5 / S1 lordosis (25.71 ) was lower than L4 / L5 lordosis (27.63 ) compared to the other groups. Although measurements of global lumbar lordosis significantly differed between the two scanning technologies, the mean difference was just 2.9 . MRI in supine position may be used for estimating global lumbar lordosis, but single level lordosis should be determined by means of standing radiographs.

  10. Definitive radiotherapy for head-and-neck cancer with radiographically positive retropharyngeal nodes: Incomplete radiographic response does not necessarily indicate failure

    International Nuclear Information System (INIS)

    Liauw, Stanley L.; Mancuso, Anthony A.; Morris, Christopher G. M.S.; Amdur, Robert J.; Mendenhall, William M.

    2006-01-01

    Purpose: Our aim was to report the control rate of radiographically positive retropharyngeal (RP) nodes with radiation therapy (RT) and to correlate posttreatment imaging with clinical outcome. Methods and Materials: Sixteen patients treated with definitive RT for head-and-neck cancer had radiographically positive RP nodes (size >1 cm in largest axial dimension, or presence of focal enhancement, lucency, or calcification), and both pre-RT and post-RT image sets available for review. An additional 21 patients with unconfirmed radiographically positive RP nodes had post-RT imaging, which consisted of computed tomography (CT) at a median of 4 weeks after completing RT. Patients with positive post-RT RP nodes underwent observation with serial imaging. Results: Of 16 patients with pre-RT and post-RT images available for review, 9 (56%) had a radiographic complete response, and of 21 patients with unconfirmed positive RP nodes with post-RT images available for review, 14 (67%) had a radiographic complete response. In all, 14 patients with incomplete response on post-RT imaging experienced control of their disease with no further therapy, and no RP node or neck failures were noted during a median follow-up of 2.8 years. Six patients with positive post-RT RP nodes had serial imaging available for review, and none demonstrated radiographic progression of disease. Conclusions: Radiographic response at 4 weeks may not accurately reflect long-term locoregional control, as RP nodes may continue to resolve over time. The highest index of suspicion should be reserved for patients with progressive changes in size, focal lucency, or focal enhancement on serial imaging after RT

  11. Study of the sensitivity of wire image quality indicators (IQI) used in radiographic testing of metals and alloys

    International Nuclear Information System (INIS)

    Sanchez, W.; Oki, H.

    1974-01-01

    Radiographic sensitivity is defined and its mathematical expresion is derived in order to justify the use of image quality indicators-IQI- formed by wires of different diameters which represent the radiographic quality. It is demonstrated that IQI sensibility is not related to the minimum dimensions of the metallic discontinuities that may be detected in radiographic tests. The experimental results are in good agreement whith the mathematical formulation proposed

  12. A computational technique to measure fracture callus in radiographs.

    Science.gov (United States)

    Lujan, Trevor J; Madey, Steven M; Fitzpatrick, Dan C; Byrd, Gregory D; Sanderson, Jason M; Bottlang, Michael

    2010-03-03

    Callus formation occurs in the presence of secondary bone healing and has relevance to the fracture's mechanical environment. An objective image processing algorithm was developed to standardize the quantitative measurement of periosteal callus area in plain radiographs of long bone fractures. Algorithm accuracy and sensitivity were evaluated using surrogate models. For algorithm validation, callus formation on clinical radiographs was measured manually by orthopaedic surgeons and compared to non-clinicians using the algorithm. The algorithm measured the projected area of surrogate calluses with less than 5% error. However, error will increase when analyzing very small areas of callus and when using radiographs with low image resolution (i.e. 100 pixels per inch). The callus size extracted by the algorithm correlated well to the callus size outlined by the surgeons (R2=0.94, p<0.001). Furthermore, compared to clinician results, the algorithm yielded results with five times less inter-observer variance. This computational technique provides a reliable and efficient method to quantify secondary bone healing response. Copyright 2009 Elsevier Ltd. All rights reserved.

  13. Radiographers and radiologists reporting plain radiograph requests from accident and emergency and general practice

    International Nuclear Information System (INIS)

    Brealey, S.D.; King, D.G.; Hahn, S.; Crowe, M.; Williams, P.; Rutter, P.; Crane, S.

    2005-01-01

    AIM: To assess selectively trained radiographers and consultant radiologists reporting plain radiographs for the Accident and Emergency Department (A and E) and general practitioners (GPs) within a typical hospital setting. METHODS: Two radiographers, a group of eight consultant radiologists, and a reference standard radiologist independently reported under controlled conditions a retrospectively selected, random, stratified sample of 400 A and E and 400 GP plain radiographs. An independent consultant radiologist judged whether the radiographer and radiologist reports agreed with the reference standard report. Clinicians then assessed whether radiographer and radiologist incorrect reports affected confidence in their diagnosis and treatment plans, and patient outcome. RESULTS: For A and E and GP plain radiographs, respectively, there was a 1% (95% confidence interval (CI) -2 to 5) and 4% (95% CI -1 to 8) difference in reporting accuracy between the two professional groups. For both A and E and GP cases there was an 8% difference in the clinicians' confidence in their diagnosis based on radiographer or radiologist incorrect reports. For A and E and GP cases, respectively, there was a 2% and 8% difference in the clinicians' confidence in their management plans based on radiographer or radiologist incorrect reports. For A and E and GP cases, respectively, there was a 1% and 11% difference in effect on patient outcome of radiographer or radiologist incorrect reports. CONCLUSION: There is the potential to extend the reporting role of selectively trained radiographers to include plain radiographs for all A and E and GP patients. Further research conducted during clinical practice at a number of sites is recommended

  14. Clinical, radiographic, and magnetic resonance imaging findings of gastrocnemius musculotendinopathy in various dog breeds.

    Science.gov (United States)

    Kaiser, Susanne M; Harms, Oliver; Konar, Martin; Staudacher, Anne; Langer, Anna; Thiel, Cetina; Kramer, Martin; Schaub, Sebastian; von Pückler, Kerstin H

    2016-11-23

    To describe clinical, radiographic, and magnetic resonance imaging (MRI) findings in 16 dogs diagnosed with gastrocnemius musculotendinopathy. Retrospective evaluation of medical records, radiographs, and MRI results, as well as follow-up completed by telephone questionnaire. Most dogs had chronic hindlimb lameness with no history of trauma or athletic activities. Clinical examination revealed signs of pain on palpation without stifle joint instability. Seven dogs had radiographic signs of osteophyte formation on the lateral fabella. Magnetic resonance imaging revealed T2 hyperintensity and uptake of contrast agent in the region of the origin of the gastrocnemius muscle. Changes were found in the lateral and medial heads of the gastrocnemius. Conservative treatment resulted in return to full function in 11 dogs. Two dogs showed partial restoration of normal function, one dog showed no improvement. Two dogs were lost to follow-up. Gastrocnemius musculotendinopathy is a potential cause of chronic hindlimb lameness in medium to large breed dogs. A history of athletic activity must not necessarily be present. Magnetic resonance imaging shows signal changes and uptake of contrast agent in the region of the origin of the gastrocnemius muscle. A combination of T1 pre- and post-contrast administration and T2 weighted sequences completed by a fat-suppressed sequence in the sagittal plane are well-suited for diagnosis. Conservative treatment generally results in return to normal function.

  15. Construction of an analytic-realistic phantom for adaptation of the radiographic techniques in any conventional X-ray equipment

    International Nuclear Information System (INIS)

    Pina, D.R.; Ghilardi Netto, T.; Trad, C.S.; Brochi, M.A. Corte; Duarte, S.B.; Pina, S.R.

    2001-01-01

    In the present work we construct a homogeneous phantom, for calibrating the X-ray beam. Each homogeneous phantom was used in the time-scale sensitometric method for obtaining a radiographic technique which is able to produce in the film, an optical density around 1,0 higher than the density of base plus fog. These radiographic techniques were applied in a anthropomorphic phantom (Rando) and its images were analyzed by specialists in radiology. They identified the best image and then a ideal radiographic technique for a standard patient with smaller doses, at any conventional X-ray equipment. (author)

  16. Online Kidney Position Verification Using Non-Contrast Radiographs on a Linear Accelerator with on Board KV X-Ray Imaging Capability

    International Nuclear Information System (INIS)

    Willis, David J.; Kron, Tomas; Hubbard, Patricia; Haworth, Annette; Wheeler, Greg; Duchesne, Gillian M.

    2009-01-01

    The kidneys are dose-limiting organs in abdominal radiotherapy. Kilovoltage (kV) radiographs can be acquired using on-board imager (OBI)-equipped linear accelerators with better soft tissue contrast and lower radiation doses than conventional portal imaging. A feasibility study was conducted to test the suitability of anterior-posterior (AP) non-contrast kV radiographs acquired at treatment time for online kidney position verification. Anthropomorphic phantoms were used to evaluate image quality and radiation dose. Institutional Review Board approval was given for a pilot study that enrolled 5 adults and 5 children. Customized digitally reconstructed radiographs (DRRs) were generated to provide a priori information on kidney shape and position. Radiotherapy treatment staff performed online evaluation of kidney visibility on OBI radiographs. Kidney dose measured in a pediatric anthropomorphic phantom was 0.1 cGy for kV imaging and 1.7 cGy for MV imaging. Kidneys were rated as well visualized in 60% of patients (90% confidence interval, 34-81%). The likelihood of visualization appears to be influenced by the relative AP separation of the abdomen and kidneys, the axial profile of the kidneys, and their relative contrast with surrounding structures. Online verification of kidney position using AP non-contrast kV radiographs on an OBI-equipped linear accelerator appears feasible for patients with suitable abdominal anatomy. Kidney position information provided is limited to 2-dimensional 'snapshots,' but this is adequate in some clinical situations and potentially advantageous in respiratory-correlated treatments. Successful clinical implementation requires customized partial DRRs, appropriate imaging parameters, and credentialing of treatment staff.

  17. X-ray image intensifier tube and radiographic camera incorporating same

    International Nuclear Information System (INIS)

    1981-01-01

    An X-ray sensitive image intensifier tube is described. It has an input window comprising at least one of iron, chromium and nickel for receiving an X-ray image. There is a flat scintillator screen adjacent for converting the X-ray image into a light pattern image. Adjacent to this is a flat photocathode layer for emitting photoelectrons in a pattern corresponding to the light pattern image. Parallel to this and spaced from it is a flat phosphor display screen. Electrostatic voltage is applied to the display screen and the photocathode layer to create an electric field between them to accelerate the photoelectrons towards the display screen. The paths of such parallel straight trajectories are governed solely by the electrostatic voltage applied, the image at the display screen being substantially equal in size to that of the X-ray image received at the input window. The tube envelope is preferably metallic to enable the basic components to be kept at a neutral potential and avoid spurious emissions. A radiographic camera with such an intensifier tube is also described. (U.K.)

  18. Measurements of simulated periodontal bone defects in inverted digital image and film-based radiograph: an in vitro study

    International Nuclear Information System (INIS)

    Molon, Rafael Scaf; Morais Camillo, Juliana Aparecida Najarro Dearo; Ferreira, Mauricio Goncalves; Loffredo, Leonor Castro Monteiro; Scaf, Gulnara; Sakakura, Celso Eduardo

    2012-01-01

    This study was performed to compare the inverted digital images and film-based images of dry pig mandibles to measure the periodontal bone defect depth. Forty 2-wall bone defects were made in the proximal region of the premolar in the dry pig mandibles. The digital and conventional radiographs were taken using a Schick sensor and Kodak F-speed intraoral film. Image manipulation (inversion) was performed using Adobe Photoshop 7.0 software. Four trained examiners made all of the radiographic measurements in millimeters a total of three times from the cementoenamel junction to the most apical extension of the bone loss with both types of images: inverted digital and film. The measurements were also made in dry mandibles using a periodontal probe and digital caliper. The Student's t-test was used to compare the depth measurements obtained from the two types of images and direct visual measurement in the dry mandibles. A significance level of 0.05 for a 95% confidence interval was used for each comparison. There was a significant difference between depth measurements in the inverted digital images and direct visual measurements (p>|t|=0.0039), with means of 6.29 mm (IC 95% :6.04-6.54) and 6.79 mm (IC 95% :6.45-7.11), respectively. There was a non-significant difference between the film-based radiographs and direct visual measurements (p>|t|=0.4950), with means of 6.64 mm(IC 95% :6.40-6.89) and 6.79 mm(IC 95% :6.45-7.11), respectively. The periodontal bone defect measurements in the inverted digital images were inferior to film-based radiographs, underestimating the amount of bone loss.

  19. Radiographers and trainee radiologists reporting accident radiographs: A comparative plain film-reading performance study

    International Nuclear Information System (INIS)

    Buskov, L.; Abild, A.; Christensen, A.; Holm, O.; Hansen, C.; Christensen, H.

    2013-01-01

    Aim: To compare the diagnostic accuracy and clinical validity of reporting radiographers with that of trainee radiologists whom they have recently joined in reporting emergency room radiographs at Bispebjerg University Hospital. Materials and methods: Plain radiographs of the appendicular skeleton from 1000 consecutive emergency room patients were included in the study: 500 primarily reported by radiographers and 500 by trainee radiologists. The final reporting was subsequently undertaken by a consultant radiologist in consensus with an orthopaedic surgeon. Two observers classified reports as either true positive/negative or false positive/negative based on the final report, which was considered the reference standard. To evaluate the severity of incorrect primary reports, errors were graded into three categories concerning clinical impact and erroneous reports graded as the most severe category were subsequently analysed. Mann–Whitney and Chi-squared tests were used to compare differences and associations between radiographers versus trainee radiologists regarding film reporting. Results: The sensitivity for correct diagnosis was 99% for reporting radiographers and 94% for trainee radiologists. The specificity was found to be 97% for reporting radiographers and 99% for trainee radiologists. Radiographers missed significantly fewer fractures (n = 2) than trainee radiologists (n = 14; p = 0.006) but had a higher, but not significant, degree of overcalling. No significant difference was found between groups regarding clinical impact of incorrect reporting. Conclusion: Trained radiographers report accident radiographs of the extremities with high accuracy and constitute a qualified resource to help meet increasing workload and demands in quality standards.

  20. Monte Carlo simulation for radiographic applications

    International Nuclear Information System (INIS)

    Tillack, G.R.; Bellon, C.

    2003-01-01

    Standard radiography simulators are based on the attenuation law complemented by built-up-factors (BUF) to describe the interaction of radiation with material. The assumption of BUF implies that scattered radiation reduces only the contrast in radiographic images. This simplification holds for a wide range of applications like weld inspection as known from practical experience. But only a detailed description of the different underlying interaction mechanisms is capable to explain effects like mottling or others that every radiographer has experienced in practice. The application of Monte Carlo models is capable to handle primary and secondary interaction mechanisms contributing to the image formation process like photon interactions (absorption, incoherent and coherent scattering including electron-binding effects, pair production) and electron interactions (electron tracing including X-Ray fluorescence and Bremsstrahlung production). It opens up possibilities like the separation of influencing factors and the understanding of the functioning of intensifying screen used in film radiography. The paper discusses the opportunities in applying the Monte Carlo method to investigate special features in radiography in terms of selected examples. (orig.) [de

  1. Search for adequate quality standards for neutron radiography of nuclear fuel

    International Nuclear Information System (INIS)

    Domanus, J.C.

    1983-01-01

    Unlike in other fields of industrial radiography, where standard methods and procedures are used to control the quality of the radiographic image, no such standard exists for neutron radiography of nuclear fuel. To fill that gap it was felt that standardization work ought to be started in that field, too. Accordingly in 1979 an Euratom Neutron Radiography Working Group was constituted, which initiated standardization work in the field of neutron radiography of nuclear fuel. Finding adequate standards for image quality of neutron radiographs and checking the accuracy of dimension measurements from them were given first priority. (Auth.)

  2. PACS influence the radiographer's work

    International Nuclear Information System (INIS)

    Fridell, Kent; Aspelin, Peter; Edgren, Lars; Lindskoeld, Lars; Lundberg, Nina

    2009-01-01

    Radiological departments are changing rapidly due to the implementation of digital images and PACS (Picture Archiving and Communication Systems). The introduction of new technology seems to dissolve boundaries between the professions in the work environment where the technology is introduced. This process tends to change the organization and its routines. The aim of this qualitative study is to explore changes in radiographers' work with regard to skills, work practice and technology. The study used open-ended interviews to explore the radiographers' perceptions of such changes, and to identify problems and solutions pertaining to work practice. Inspiration is taken from grounded theory to explain the changes in work that were found. Respondents were selected from a total of 133 potential participants as a theoretical or purposive sample. The changing trends within the professional role indicated that radiographers, as image producers, shifted their focus from the ability to set the optimal exposure parameters in order to obtain the optimal image for diagnosis to become expert in exposure parameters, projection techniques and diagnostic practice, having multifaceted skills, as being the jack of all trades. When implementing PACS there was an obvious change in image production. At the start there were visions of new routines, and therefore the radiographers became early adopters to the new technology; in practice the organization was stacked in old routines, as the routines were inflexible and PACS work was pushed into old work routines. Although inflexible, this does not mean that they cannot change, and obviously in 2006 new routines had been implemented making it possible for the radiographers in finding new ways for collaborating with colleagues. The new technology immediately created a vision of improved service to the clinicians. In order to optimize the service the radiographers developed an insight into the need for a more comprehensive change in work using

  3. Angular relational signature-based chest radiograph image view classification.

    Science.gov (United States)

    Santosh, K C; Wendling, Laurent

    2018-01-22

    In a computer-aided diagnosis (CAD) system, especially for chest radiograph or chest X-ray (CXR) screening, CXR image view information is required. Automatically separating CXR image view, frontal and lateral can ease subsequent CXR screening process, since the techniques may not equally work for both views. We present a novel technique to classify frontal and lateral CXR images, where we introduce angular relational signature through force histogram to extract features and apply three different state-of-the-art classifiers: multi-layer perceptron, random forest, and support vector machine to make a decision. We validated our fully automatic technique on a set of 8100 images hosted by the U.S. National Library of Medicine (NLM), National Institutes of Health (NIH), and achieved an accuracy close to 100%. Our method outperforms the state-of-the-art methods in terms of processing time (less than or close to 2 s for the whole test data) while the accuracies can be compared, and therefore, it justifies its practicality. Graphical Abstract Interpreting chest X-ray (CXR) through the angular relational signature.

  4. Image processings of radiographs in the gastric cancer cases

    International Nuclear Information System (INIS)

    Inamoto, Kazuo; Yamashita, Kazuya; Morikawa, Kaoru; Takigawa, Atsushi

    1987-01-01

    For improving detectability of the gastric lesions in the X-ray examinations, the computer image processing methods were studied in radiographs of a stomach phantom and gastric cancer lesions by the A/D conversion. After several kinds of the basic processing methods were examined in the artificially made lesions in the stomach phantom and true gastric cancer lesions in 26 X-ray pictures of the 8 gastric cancer cases, we concluded that pathological changes on the edge or mucosal folds in the stomach were stressed by the image processing method using negative to positive conversion, density gradient control, edge enhancement (Sobel operation) and subtraction of the Sobel image from the original image. These methods contributed to interpretation of the gastric cancer by enhancement of the contour and mucosal pattern inside the lesion. The results were applied for follow up studies of the gastric cancer. Tumor expansions could be clarified, but it was yet difficult to catch a precancer lesion by retrospective studies. However, these methods would be expected in future application in the mass survey examination of the gastric cancer detection. (author)

  5. Stereoscopic radiographic images with thermal neutrons

    Science.gov (United States)

    Silvani, M. I.; Almeida, G. L.; Rogers, J. D.; Lopes, R. T.

    2011-10-01

    Spatial structure of an object can be perceived by the stereoscopic vision provided by eyes or by the parallax produced by movement of the object with regard to the observer. For an opaque object, a technique to render it transparent should be used, in order to make visible the spatial distribution of its inner structure, for any of the two approaches used. In this work, a beam of thermal neutrons at the main port of the Argonauta research reactor of the Instituto de Engenharia Nuclear in Rio de Janeiro/Brazil has been used as radiation to render the inspected objects partially transparent. A neutron sensitive Imaging Plate has been employed as a detector and after exposure it has been developed by a reader using a 0.5 μm laser beam, which defines the finest achievable spatial resolution of the acquired digital image. This image, a radiographic attenuation map of the object, does not represent any specific cross-section but a convoluted projection for each specific attitude of the object with regard to the detector. After taking two of these projections at different object attitudes, they are properly processed and the final image is viewed by a red and green eyeglass. For monochromatic images this processing involves transformation of black and white radiographies into red and white and green and white ones, which are afterwards merged to yield a single image. All the processes are carried out with the software ImageJ. Divergence of the neutron beam unfortunately spoils both spatial and contrast resolutions, which become poorer as object-detector distance increases. Therefore, in order to evaluate the range of spatial resolution corresponding to the 3D image being observed, a curve expressing spatial resolution against object-detector gap has been deduced from the Modulation Transfer Functions experimentally. Typical exposure times, under a reactor power of 170 W, were 6 min for both quantitative and qualitative measurements. In spite of its intrinsic constraints

  6. Stereoscopic radiographic images with thermal neutrons

    International Nuclear Information System (INIS)

    Silvani, M.I.; Almeida, G.L.; Rogers, J.D.; Lopes, R.T.

    2011-01-01

    Spatial structure of an object can be perceived by the stereoscopic vision provided by eyes or by the parallax produced by movement of the object with regard to the observer. For an opaque object, a technique to render it transparent should be used, in order to make visible the spatial distribution of its inner structure, for any of the two approaches used. In this work, a beam of thermal neutrons at the main port of the Argonauta research reactor of the Instituto de Engenharia Nuclear in Rio de Janeiro/Brazil has been used as radiation to render the inspected objects partially transparent. A neutron sensitive Imaging Plate has been employed as a detector and after exposure it has been developed by a reader using a 0.5 μm laser beam, which defines the finest achievable spatial resolution of the acquired digital image. This image, a radiographic attenuation map of the object, does not represent any specific cross-section but a convoluted projection for each specific attitude of the object with regard to the detector. After taking two of these projections at different object attitudes, they are properly processed and the final image is viewed by a red and green eyeglass. For monochromatic images this processing involves transformation of black and white radiographies into red and white and green and white ones, which are afterwards merged to yield a single image. All the processes are carried out with the software ImageJ. Divergence of the neutron beam unfortunately spoils both spatial and contrast resolutions, which become poorer as object-detector distance increases. Therefore, in order to evaluate the range of spatial resolution corresponding to the 3D image being observed, a curve expressing spatial resolution against object-detector gap has been deduced from the Modulation Transfer Functions experimentally. Typical exposure times, under a reactor power of 170 W, were 6 min for both quantitative and qualitative measurements. In spite of its intrinsic constraints

  7. Survey of image quality and radiographic technique of pediatric chest examinations performed in Latin America

    International Nuclear Information System (INIS)

    Khoury, H.; Mora, P.; Defaz, M.Y.; Blanco, S.; Leyton, F.; Benavente, T.; Ortiz Lopez, P.; Ramirez, R.

    2008-01-01

    This work presents the results of a survey of entrance surface air kerma values (K e ), image quality and radiographic exposure parameters used in pediatric chest examinations performed in Latin America. This study is part of the activities of the IAEA Regional Project RLA/9/057 whose objective is to optimize the radiological protection of patients in diagnostic and interventional radiology, nuclear medicine and radiotherapy. The survey was performed in nine hospitals in Argentina (1), Brazil (4), Chile (1), Costa Rica (1), Peru (1) and Ecuador (1). The study group consisted of 462 pediatric patients (Group I- from two days to one year, Group II- from four to six years of age) undergoing chest PA/AP examinations. At the time of the examination the exposure parameters (kVp, mAs, focal-spot-to-film distance, etc.) and patient information (gender, height, weight and age) were recorded. The radiographic image quality was evaluated by the local radiologist based on the European Guidelines on Quality Criteria for Diagnostic Radiographic Images in Pediatrics. The results showed that the exposure parameters used on newborn patients were in the majority outside the 60-65kV range recommended by the European Guidelines for a good radiographic practice. In the case of examinations of patients with age between 4 to 6 years, 80% were performed with a peak tube voltage within the 60-80 kV range, as recommended by the European Guidelines. It was found that none of countries fully comply with the European Guidelines on Quality Criteria and those criteria No. 2 and No. 3 (reproduction of the chest without rotation) received the lowest scores. Probably this occurs because there are no proper patient immobilization devices. The Ke values, for both patient groups, showed a wide dispersion, ranged from 10 μGy to 160μGy for the newborn patients and from 20μGy to 240μGy for infant patients. It is possible to conclude that, in the participating Latin American countries on this project

  8. The influence of dental implants in periapical and panoramic radiographs and cone beam computed tomography images: a clinical study.

    Science.gov (United States)

    Felix, Rafael Perdomo; Shinkai, Rosemary Sadami Arai; Rockenbach, Maria Ivete Bolzan

    2018-01-01

    The aim of this study was to analyze the influence of dental implants on the radiographic density of the peri-implant region in tomographic and radiographic examinations. A sample of 21 dental implants from 10 patients with Brånemark-protocol prostheses was evaluated based on postoperative control images, including periapical radiography (paralleling technique), panoramic radiography, and cone beam computed tomography (CBCT). The density means of 6 defined areas near dental implants were calculated and compared considering their locations and the different imaging examinations. The CBCT examinations showed significantly different densities among the measured areas (P implants in all the examinations: CBCT (127.88 and 120.71), panoramic (106.51 and 106.09), and periapical (120.32). The sagittal CBCT images were measured in 2 different sections, and in both sections those areas closer to implants showed mean densities that were significantly higher than means from more distant areas (P implant region confirmed the interference of dental implants in radiographic and tomographic images. CBCT images suffered the greatest interference from dental implants.

  9. Development and Assessment of an E-Learning Course on Breast Imaging for Radiographers: A Stratified Randomized Controlled Trial

    Science.gov (United States)

    Ventura, Sandra Rua; Ramos, Isabel; Rodrigues, Pedro Pereira

    2015-01-01

    Background Mammography is considered the best imaging technique for breast cancer screening, and the radiographer plays an important role in its performance. Therefore, continuing education is critical to improving the performance of these professionals and thus providing better health care services. Objective Our goal was to develop an e-learning course on breast imaging for radiographers, assessing its efficacy, effectiveness, and user satisfaction. Methods A stratified randomized controlled trial was performed with radiographers and radiology students who already had mammography training, using pre- and post-knowledge tests, and satisfaction questionnaires. The primary outcome was the improvement in test results (percentage of correct answers), using intention-to-treat and per-protocol analysis. Results A total of 54 participants were assigned to the intervention (20 students plus 34 radiographers) with 53 controls (19+34). The intervention was completed by 40 participants (11+29), with 4 (2+2) discontinued interventions, and 10 (7+3) lost to follow-up. Differences in the primary outcome were found between intervention and control: 21 versus 4 percentage points (pp), Pe-learning course is effective, especially for radiographers, which highlights the need for continuing education. PMID:25560547

  10. The effect of personalized versus standard patient protocols for radiostereometric analysis (RSA)

    DEFF Research Database (Denmark)

    Muharemovic, O; Troelsen, A; Thomsen, M G

    2018-01-01

    INTRODUCTION: Increasing pressure in the clinic requires a more standardized approach to radiostereometric analysis (RSA) imaging. The aim of this study was to investigate whether implementation of personalized RSA patient protocols could increase image quality and decrease examination time...... imaging. Radiographers in the control group used a standard RSA protocol. RESULTS: At three months, radiographers in the case group significantly reduced (p .... No significant improvements were found in the control group at any time point. CONCLUSION: There is strong evidence that personalized RSA patient protocols have a positive effect on image quality and radiation dose savings. Implementation of personal patient protocols as a RSA standard will contribute...

  11. A study of trabecular bone strength and morphometric analysis of bone microstructure from digital radiographic image

    International Nuclear Information System (INIS)

    Han, Seung Yun; Lee, Sun Bok; Oh, Sung Ook; Heo, Min Suk; Lee, Sam Sun; Choi, Soon Chul; Park, Tae Won; Kim, Jong Dae

    2003-01-01

    To evaluate the relationship between morphometric analysis of microstructure from digital radiographic image and trabecular bone strength. One hundred eleven bone specimens with 5 mm thickness were obtained from the mandibles of 5 pigs. Digital images of specimens were taken using a direct digital intraoral radiographic system. After selection of ROI(100 x 100 pixel) within the trabecular bone, mean gray level and standard deviation were obtained. Fractal dimension and the variants of morphometric analysis (trabecular area, periphery, length of skeletonized trabeculae, number of terminal point, number of branch point) were obtained from ROI. Punch sheer strength analysis was performed using Instron (model 4465, Instron Corp., USA). The loading force (loading speed 1mm/min) was applied to ROI of bone specimen by a 2 mm diameter punch. Stress-deformation curve was obtained from the punch sheer strength analysis and maximum stress, yield stress, Young's modulus were measured. Maximum stress had a negative linear correlation with mean gray level and fractal dimension significantly (p<0.05). Yield stress had a negative linear correlation with mean gray level, periphery, fractal dimension and the length of skeletonized trabeculae significantly (p<0.05). Young's modulus had a negative linear correlation with mean gray level and fractal dimension significantly (p<0.05). The strength of cancellous bone exhibited a significantly linear relationship between mean gray level, fractal dimension and morphometric analysis. The methods described above can be easily used to evaluate bone quality clinically.

  12. Caries detection in dental radiographs

    International Nuclear Information System (INIS)

    Dunn, S.M.

    1987-01-01

    Caries, or the decay of teeth are difficult to automatically detect in dental radiographs because of the small area of the image that is occupied by the decay. Images of dental radiographs has distinct regions of homogeneous gray levels, and therefore naturally lead to a segmentation based automatic caries detection algorithm. This paper describes a method for caries detection based on a multiclass, area independent thresholding and segmenting scheme. This multiclass thresholding algorithm is an extension of the uniform error threshold, an area independent, distribution free thresholding method used for images of only two classes of objects. The authors first consider the problem of caries detection and the image features that characterize the presence of caries. Next, the uniform error threshold is reviewed, and the general multiclass uniform error threshold algorithm is presented. This algorithm is used to automatically detect caries in dental radiographs

  13. Prototype radiographic system for emergency and intensive care units: Initial experience

    International Nuclear Information System (INIS)

    Mirvis, S.

    1986-01-01

    A prototype radiographic system has been developed for use in bedside examinations in multibed trauma or intensive care units and emergency rooms. The system features a single-phase, high-frequency 30-kW ceiling-mounted generator with an x-ray tube extending from a long counterbalanced arm. All movements are servo-assisted for ease of operation. Based on initial experience, the unit allows easier access to the patient around resuscitation and monitoring equipment, occupies less floor space, and yields better quality images than do standard mobile radiographic units

  14. Digitized hand-wrist radiographs: comparison of subjective and software-derived image quality at various compression ratios.

    Science.gov (United States)

    McCord, Layne K; Scarfe, William C; Naylor, Rachel H; Scheetz, James P; Silveira, Anibal; Gillespie, Kevin R

    2007-05-01

    The objectives of this study were to compare the effect of JPEG 2000 compression of hand-wrist radiographs on observer image quality qualitative assessment and to compare with a software-derived quantitative image quality index. Fifteen hand-wrist radiographs were digitized and saved as TIFF and JPEG 2000 images at 4 levels of compression (20:1, 40:1, 60:1, and 80:1). The images, including rereads, were viewed by 13 orthodontic residents who determined the image quality rating on a scale of 1 to 5. A quantitative analysis was also performed by using a readily available software based on the human visual system (Image Quality Measure Computer Program, version 6.2, Mitre, Bedford, Mass). ANOVA was used to determine the optimal compression level (P quality. When we used quantitative indexes, the JPEG 2000 images had lower quality at all compression ratios compared with the original TIFF images. There was excellent correlation (R2 >0.92) between qualitative and quantitative indexes. Image Quality Measure indexes are more sensitive than subjective image quality assessments in quantifying image degradation with compression. There is potential for this software-based quantitative method in determining the optimal compression ratio for any image without the use of subjective raters.

  15. The use of reference image criteria in X-ray diagnostics: an application for the optimisation of lumbar spine radiographs

    International Nuclear Information System (INIS)

    Almen, A.; Tingberg, A.; Mattsson, S.; Besjakov, J.

    2004-01-01

    To ensure that sufficient image quality is obtained in diagnostic radiology, the image quality of clinical radiographs has to be evaluated. We present two methods herein for evaluating antero-posterior (AP) radiographs of the lumbar spine. One was using image criteria, including six anatomical details (absolute method). In the other, the visibility of anatomical details relative to a reference radiograph was evaluated (visual grading analysis). In total, 14 technique groups were evaluated. The technique groups differed in tube voltage and detector system characteristics. Six different gradients of the H and D curves were simulated. The visual grading analysis showed larger differences in image quality compared with the absolute method. The influence on the image quality due to a variation in tube voltage was easier to detect than the influence on the image quality from the detector characteristics. The visibility of the anatomical details was significantly dependent on the location in the spine. The visual grading analysis was found to be the preferable evaluation method in studies such as the present; however, it is necessary to guide and train the observer before the evaluation is performed. (orig.)

  16. Measurements of simulated periodontal bone defects in inverted digital image and film-based radiograph: an in vitro study

    Energy Technology Data Exchange (ETDEWEB)

    Molon, Rafael Scaf; Morais Camillo, Juliana Aparecida Najarro Dearo; Ferreira, Mauricio Goncalves; Loffredo, Leonor Castro Monteiro; Scaf, Gulnara [Araraquara Dental School, Universidade Estadual Paulista, Sao Paulo (Brazil); Sakakura, Celso Eduardo [Barretos Dental School, Barretos Educational Fundation, Sao Paulo (Brazil)

    2012-09-15

    This study was performed to compare the inverted digital images and film-based images of dry pig mandibles to measure the periodontal bone defect depth. Forty 2-wall bone defects were made in the proximal region of the premolar in the dry pig mandibles. The digital and conventional radiographs were taken using a Schick sensor and Kodak F-speed intraoral film. Image manipulation (inversion) was performed using Adobe Photoshop 7.0 software. Four trained examiners made all of the radiographic measurements in millimeters a total of three times from the cementoenamel junction to the most apical extension of the bone loss with both types of images: inverted digital and film. The measurements were also made in dry mandibles using a periodontal probe and digital caliper. The Student's t-test was used to compare the depth measurements obtained from the two types of images and direct visual measurement in the dry mandibles. A significance level of 0.05 for a 95% confidence interval was used for each comparison. There was a significant difference between depth measurements in the inverted digital images and direct visual measurements (p>|t|=0.0039), with means of 6.29 mm (IC{sub 95%}:6.04-6.54) and 6.79 mm (IC{sub 95%}:6.45-7.11), respectively. There was a non-significant difference between the film-based radiographs and direct visual measurements (p>|t|=0.4950), with means of 6.64 mm(IC{sub 95%}:6.40-6.89) and 6.79 mm(IC{sub 95%}:6.45-7.11), respectively. The periodontal bone defect measurements in the inverted digital images were inferior to film-based radiographs, underestimating the amount of bone loss.

  17. Image analysis of bubble behavior in the pressurized fluidized bed using neutron radiograph

    International Nuclear Information System (INIS)

    Katoh, Yasuo; Miyamoto, Masahide; Miike, Hidetoshi; Kishimoto, Yasuyuki; Matsubayasi, Masahito; Mochiki, Kouichi.

    1996-01-01

    It is very important to know about the formation for bubble production growth and destruction. Because blowing gas nozzle decide the ability of the solid-gas fluidized bed system. For the pressurized 3-D fluidized bed, it was some interested in the bubble production and configuration which was taken place the interaction between bubble and particle under the pressurized condition. For the understanding of the three dimensional characteristics of production bubble under pressurized condition, the study of visualization of neutron radiograph seemed to be useful. In stead of typical X-ray visualization method, visualization of neutron radiograph method for observation of bubble behavior were carried out. Then an image analysis of it was done the same way as two dimension method P-system (PIAS-LA555WS Image Analysis). As the results, the characteristic of production bubble was more clear quantitatively, for example, the bubble production frequency, the bubble diameter and the bubble horizontal and vertical sizes so on. (author)

  18. Immobilisation-induced changes in forearm bone quantity and quality: radiographic fourier image analysis vs bone densitometry

    International Nuclear Information System (INIS)

    Moore, G.; Price, R.I.; Buck, A.M.; University of Western Australia, Nedlands, WA; Price, R.L.; University of Western Australia, Nedlands, WA; Sweetman, I.M.; Ho, S.

    1996-01-01

    Full text: Determinants of bone fracture risk include indices of bone 'quantity' such as bone mineral content (BMC, mineral mass per unit scanned bone length), plus 'environmental' (eg impact force) and 'quality' factors (Melton L.J. III et al, Bone and Min 2: 321, 1987). Bone 'quality' refers largely to the micro-geometry of bone (∼ 10-200μ), but has been less well studied because of the need for bone slices from (invasive) bone biopsies. Such studies often compare the geometry of trabecular networks (eg trabecular bone volume, trabecular number) with clinical outcomes such as fracture rates. Another (invasive) approach is to examine the two-dimensional (2-D) Fourier transform (FT) of a high-resolution radiographic image of the bone slice, since structural information is in theory encoded in the 2-D spatial-frequency (ν) spectrum. Additionally, the FT method can be applied to bone images obtained in-vivo, though superposition of information from the third dimension is a major confounding factor in their interpretation. Quantitative radiography of the ultradistal (UD) forearm permits determination of BMC (Price R et al; ACPSEM 6: 128- 137, 1983 and ACPSEM 11: 36-43, 1988), and (as a bonus) reveals a pattern (suitable for FT analysis) of the radiographic shadows of the 3-D trabecular network projected onto the image plane. Hemiplegia is associated with excessive bone loss in the paralysed (hemi) forearm, and is a model for the study of immobilisation osteoporosis. Thus, by comparing hemiplegia-induced changes in BMC and trabecular structure, derived from the same in vivo radiographic image, it is possible to compare directly the effects of disease on both bone quantity and quality, using the image of the non-paralysed (non-hemi) arm as a control. Seventy-four patients with hemiplegia of duration 3.6±3.6 (Mean±SD) years were studied cross-sectionally for radiographic BMC of their normal and paralysed UD forearms in AP view, each arm in duplicate. Methods

  19. Radiographic Co-60 in component of heavy equipment casting

    International Nuclear Information System (INIS)

    Djoli Soembogo, Harun Al Rasyid R dan Namad Sianta

    2016-01-01

    The application of radiography using isotope Co-60 source has been used on component of heavy equipment such as component of heavy equipment casting. Components of heavy equipment casting made through metal casting of carbon steel. This study tried applying digital radiography are using isotope Co-60 sources and using scanning positive film media of Epson V700 for digitization results of conventional radiographic films. This radiography is using film AGFA D7 and Fuji 100 to obtain a contrast medium, medium sensitivity and image quality is good. The purpose radiographic Co-60 at a component of heavy equipment casting is detecting indications of the shape and type casting defects of component of heavy equipment casting thus fit for use. Radiographic test of Co-60 has been carried out on component of heavy equipment casting with single wall single image method and the results of radiographic films digitization using scanning positive film media of Epson V700 with observation parameters casting defects. Time exposure of Co-60 radiation was 10 and 15 minutes hours for metal castings of carbon steel for thickness 20.00-50.00 mm by using activity 30.05 Ci and the perpendicular distance to the source of the film is 820 mm. Scanner positive film results in the form of digital radiography which allow for the transfer of digital data or digital computerized data storage. Radiographic test results on component of heavy equipment casting with single wall single image method produce the parameter casting defect of component of heavy equipment casting in position of critical area is found shrinkage that should be repaired and in position of safety area is not found defect indication so casting defect of component of heavy equipment casting are not acceptable according to standards referenced. (author)

  20. A descriptive study of the radiographic density of implant restorative cements.

    Science.gov (United States)

    Wadhwani, Chandur; Hess, Timothy; Faber, Thomas; Piñeyro, Alfonso; Chen, Curtis S K

    2010-05-01

    Cementation of implant prostheses is a common practice. Excess cement in the gingival sulcus may harm the periodontal tissues. Identification of the excess cement may be possible with the use of radiographs if the cement has sufficient radiopacity. The purpose of this study was to compare the radiographic density of different cements used for implant prostheses. Eight different cements were compared: TempBond Original (TBO), TempBond NE (TBN), Fleck's (FL), Dycal (DY), RelyX Unicem (RXU), RelyX Luting (RXL), Improv (IM), and Premier Implant Cement (PIC). Specimen disks, 2 mm in thickness, were radiographed. Images were made using photostimulable phosphor (PSP) plates with standardized exposure values. The average grey level of the central area of each specimen disk was selected and measured in pixels using a software analysis program, ImageTool, providing an average grey level value representative of radiodensity for each of the 8 cements. The radiodensity was determined using the grey level values of the test materials, which were recorded and compared to a standard aluminum step wedge. An equivalent thickness of aluminum in millimeters was calculated using best straight line fit estimates. To assess contrast effects by varying the exposure settings, a second experiment using 1-mm-thick cement specimens radiographed at both 60 kVp and 70 kVp was conducted. The PSP plates with specimens were measured for a grey level value comparison to the standard aluminum step wedge, using the same software program. The highest grey level values were recorded for the zinc cements (TBO, TBN, and FL), with the 1-mm specimen detectable at both 60- and 70-kVp settings. A lower grey level was recorded for DY, indicative of a lower radiodensity compared to the zinc cements, but higher than RXL and RXU. The implant-specific cements had the lowest grey level values. IM could only be detected in 2-mm-thick sections with a lower aluminum equivalence value than the previously mentioned

  1. Transcranial radiograph and magnetic resonance imaging in the evaluation of osseous changes of the temporomandibular joint

    International Nuclear Information System (INIS)

    Cho, Soo Beom; Koh, Kwang Joon

    2002-01-01

    To evaluate the diagnostic accuracy of transcranial radiographs and magnetic resonance imaging (MRI) of the temporomandibular joint (TMJ) in the assessment of osseous changes of the condylar head and articular eminence. Osseous changes of the TMJ were evaluated in forty-three patients. Osseous changes of the condylar head and articular eminence were observed in 41 joints and 64 joints, respectively on transcranial radiographs, and 48 joints and 59 joints, respectively on MRI. The flattening, sclerosis, erosion, and osteophyte formation of the condylar heads were observed in 36.6%, 43.9%, 12.2%, and 7.3%, respectively on transcranial radiographs compared with 35.4%, 20.8%, 37.5%, and 6.3%, respectively on MRI. While, the flattening, sclerosis, and erosion of the articular eminences were observed in 26.6%, 67.2%, and 6.2%, respectively on transcranial radiographs compared with 32.2%, 59.3%, and 8.5%, respectively on MRI. There were no statistical differences between transcranial radiographs and MRI scans in the detection of osseous changes of the TMJ. However, MRI scans were superior to the transcranial radiographs in the detection of erosion of the condylar head (p<0.01).

  2. Transcranial radiograph and magnetic resonance imaging in the evaluation of osseous changes of the temporomandibular joint

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Soo Beom; Koh, Kwang Joon [School of Dentistry, Chonbuk National University, Chonju (Korea, Republic of)

    2002-06-15

    To evaluate the diagnostic accuracy of transcranial radiographs and magnetic resonance imaging (MRI) of the temporomandibular joint (TMJ) in the assessment of osseous changes of the condylar head and articular eminence. Osseous changes of the TMJ were evaluated in forty-three patients. Osseous changes of the condylar head and articular eminence were observed in 41 joints and 64 joints, respectively on transcranial radiographs, and 48 joints and 59 joints, respectively on MRI. The flattening, sclerosis, erosion, and osteophyte formation of the condylar heads were observed in 36.6%, 43.9%, 12.2%, and 7.3%, respectively on transcranial radiographs compared with 35.4%, 20.8%, 37.5%, and 6.3%, respectively on MRI. While, the flattening, sclerosis, and erosion of the articular eminences were observed in 26.6%, 67.2%, and 6.2%, respectively on transcranial radiographs compared with 32.2%, 59.3%, and 8.5%, respectively on MRI. There were no statistical differences between transcranial radiographs and MRI scans in the detection of osseous changes of the TMJ. However, MRI scans were superior to the transcranial radiographs in the detection of erosion of the condylar head (p<0.01).

  3. Radiographic findings in late-presenting congenital diaphragmatic hernia: helpful imaging findings

    International Nuclear Information System (INIS)

    Muzzafar, Sofia; Swischuk, Leonard E.; Jadhav, Siddharth P.

    2012-01-01

    Imaging findings in delayed presentation of congenital diaphragmatic hernia can be confusing and misleading, resulting in a delay in diagnosis. To evaluate the often puzzling plain film findings of late-presenting CDH in an effort to determine whether any of the findings could be helpful in arriving at an early diagnosis. We reviewed and documented the plain film findings and clinical data in eight patients seen during the last 20 years with late-presenting CDH. IRB exempt status was obtained in this study. There were five boys and three girls. The age range was 4 months to 12 years with a mean of 2.4 years. Five children presented with acute respiratory problems while three presented with acute abdominal pain. Two children presented with both respiratory and abdominal findings and one also presented with hematemesis. Two children had radiographic findings that were not difficult to analyze while the remaining six had findings that posed initial diagnostic problems. Although not common, late-presenting CDH can result in confusing plain film radiographic findings and a delay in diagnosis. We found that the most important finding in analyzing these radiographs is in evaluating the location and position of the gastric bubble with the more common left-side hernias. (orig.)

  4. Radiographic findings in late-presenting congenital diaphragmatic hernia: helpful imaging findings

    Energy Technology Data Exchange (ETDEWEB)

    Muzzafar, Sofia; Swischuk, Leonard E.; Jadhav, Siddharth P. [University of Texas Medical Branch, Department of Pediatric Radiology, Galveston, TX (United States)

    2012-03-15

    Imaging findings in delayed presentation of congenital diaphragmatic hernia can be confusing and misleading, resulting in a delay in diagnosis. To evaluate the often puzzling plain film findings of late-presenting CDH in an effort to determine whether any of the findings could be helpful in arriving at an early diagnosis. We reviewed and documented the plain film findings and clinical data in eight patients seen during the last 20 years with late-presenting CDH. IRB exempt status was obtained in this study. There were five boys and three girls. The age range was 4 months to 12 years with a mean of 2.4 years. Five children presented with acute respiratory problems while three presented with acute abdominal pain. Two children presented with both respiratory and abdominal findings and one also presented with hematemesis. Two children had radiographic findings that were not difficult to analyze while the remaining six had findings that posed initial diagnostic problems. Although not common, late-presenting CDH can result in confusing plain film radiographic findings and a delay in diagnosis. We found that the most important finding in analyzing these radiographs is in evaluating the location and position of the gastric bubble with the more common left-side hernias. (orig.)

  5. Radiographic findings in late-presenting congenital diaphragmatic hernia: helpful imaging findings.

    Science.gov (United States)

    Muzzafar, Sofia; Swischuk, Leonard E; Jadhav, Siddharth P

    2012-03-01

    Imaging findings in delayed presentation of congenital diaphragmatic hernia can be confusing and misleading, resulting in a delay in diagnosis. To evaluate the often puzzling plain film findings of late-presenting CDH in an effort to determine whether any of the findings could be helpful in arriving at an early diagnosis. We reviewed and documented the plain film findings and clinical data in eight patients seen during the last 20 years with late-presenting CDH. IRB exempt status was obtained in this study. There were five boys and three girls. The age range was 4 months to 12 years with a mean of 2.4 years. Five children presented with acute respiratory problems while three presented with acute abdominal pain. Two children presented with both respiratory and abdominal findings and one also presented with hematemesis. Two children had radiographic findings that were not difficult to analyze while the remaining six had findings that posed initial diagnostic problems. Although not common, late-presenting CDH can result in confusing plain film radiographic findings and a delay in diagnosis. We found that the most important finding in analyzing these radiographs is in evaluating the location and position of the gastric bubble with the more common left-side hernias.

  6. Diagnostic efficacy of standard knee magnetic resonance imaging and radiography in evaluating integrity of anterior cruciate ligament before unicompartmental knee arthroplasty.

    Science.gov (United States)

    Altınel, Levent; Er, Mehmet Serhan; Kaçar, Emre; Erten, Recep Abdullah

    2015-01-01

    The purpose of this study was to investigate the diagnostic efficacy of standard magnetic resonance imaging (MRI) and plain radiographs in determining the status of anterior cruciate ligament (ACL) for surgical decision-making processes in cases of medial unicompartmental knee arthroplasty (UKA). A total of 59 knees of 36 consecutive patients who underwent knee replacement surgery were analyzed retrospectively. MRI scans were assessed independently by 3 observers (radiologists), while the plain radiographs were evaluated by an independent radiologist. Results were compared with the intraoperative ACL status. Cross tabulation was used for descriptive statistics to analyze sensitivity, specificity, and accuracy of MRI and plain radiographs. When the same observer assessed and classified the MRI twice, the reproducibility of the classification system varied from moderate to excellent. However, the interobserver concordance was moderate. The sensitivity of MRI was 73% and the specificity was 81%, while the sensitivity and specificity of plain radiographs was 36% and 79%, respectively. The accuracy of MRI was 80%, while that of the radiographs was 71%. Detection of intact ACL may be possible on available plain radiographs without necessity for additional means such as MRI, which may cause increase costs and loss of time. In cases where there is uncertainty regarding ACL integrity in degenerative knees, although standard MRI provides additional information on ACL status, it is not of sufficient diagnostic value.

  7. Pocket atlas of radiographic anatomy

    International Nuclear Information System (INIS)

    Moeller, T.B.; Reif, E.; Stark, P.

    1993-01-01

    The 'Pocket Atlas of Radiographic Anatomy' presents 170 radiographs of the various body regions of adults, showing only the normal radiographic anatomy. Each radiograph is supplemented on the opposite page by a drawing of the particular body region. There is no commenting text, but the drawings are provided with captions in English. The atlas is a useful guide for interpreting radiographs. The pictures are arranged in chapters entitled as follows: Skeletal Imaging (skull, spine, upper extremity), lower extremity; Miscellaneous Plain Films (chest, mammogram, trachea, lung tomograms); Contrast Examinations (gastrointestinal tract, intravenous contrast examinations, arthrography, angiography); Special Examinations (myelograms, lymphangiograms, bronchograms, sialograms). (UWA). 348 figs [de

  8. Method for taking X radiographs

    International Nuclear Information System (INIS)

    Orth, G.

    1983-01-01

    The method is aimed at obtaining X radiographs of any human organ with the aid of an X-ray-shadowless radiation detector of a dose measuring device, which is arranged between patient and imaging system, and of a controlling microprocessor system, so that the image-forming parameters are automatically adjusted to the specific properties of the patient. This procedure minimices the efforts in preparing the radiograph and the radiation exposure of the patient

  9. 42 CFR Appendix A to Part 75 - Standards for Accreditation of Educational Programs for Radiographers

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Standards for Accreditation of Educational Programs for Radiographers A Appendix A to Part 75 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH... film evaluation; (k) Methods of patient care; (l) Pathology; (m) Radiologic physics; and (n) Radiation...

  10. Physical and clinical evaluation of new high-strip-density radiographic grids

    International Nuclear Information System (INIS)

    Doi, K.; Frank, P.H.; Chan, H.P.; Vyborny, C.J.; Makino, S.; Iida, N.; Carlin, M.

    1983-01-01

    The imaging performance of new high-strip-density (HSD) grids having 57 lines/cm was compared with that of conventional low-strip-density (LSD) grids having 33 or 40 lines/cm. The unique advantage of HSD grids is that, under most standard radiographic conditions, the grid lines are not noticeable on the final image, even if the grid is stationary. This is due to the combined effect of the high fundamental spatial frequency of HSD grids, the modulation transfer function of screen-film systems and of the human visual system, and scattered radiation. Monte Carlo simulation studies, phantom images, and clinical evaluation indicate that HSD grids can provide contrast improvement factors and Bucky factors that are comparable to or slightly better than those obtained with LSD grids. Therefore, it may now be possible to eliminate moving Bucky trays from radiographic tables and fluoroscopic devices

  11. Development and assessment of an e-learning course on breast imaging for radiographers: a stratified randomized controlled trial.

    Science.gov (United States)

    Moreira, Inês C; Ventura, Sandra Rua; Ramos, Isabel; Rodrigues, Pedro Pereira

    2015-01-05

    Mammography is considered the best imaging technique for breast cancer screening, and the radiographer plays an important role in its performance. Therefore, continuing education is critical to improving the performance of these professionals and thus providing better health care services. Our goal was to develop an e-learning course on breast imaging for radiographers, assessing its efficacy, effectiveness, and user satisfaction. A stratified randomized controlled trial was performed with radiographers and radiology students who already had mammography training, using pre- and post-knowledge tests, and satisfaction questionnaires. The primary outcome was the improvement in test results (percentage of correct answers), using intention-to-treat and per-protocol analysis. A total of 54 participants were assigned to the intervention (20 students plus 34 radiographers) with 53 controls (19+34). The intervention was completed by 40 participants (11+29), with 4 (2+2) discontinued interventions, and 10 (7+3) lost to follow-up. Differences in the primary outcome were found between intervention and control: 21 versus 4 percentage points (pp), Peffect in radiographers (23 pp vs 4 pp; P=.004) but was unclear in students (18 pp vs 5 pp; P=.098). Nonetheless, differences in students' posttest results were found (88% vs 63%; P=.003), which were absent in pretest (63% vs 63%; P=.106). The per-protocol analysis showed a higher effect (26 pp vs 2 pp; Pe-learning course is effective, especially for radiographers, which highlights the need for continuing education.

  12. Radiographic Detectability of Retained Neuropatties in a Cadaver Model.

    Science.gov (United States)

    Luo, Wangjian Thomas; Almack, Robert; Mawson, John B; Cochrane, David Douglas

    2015-08-01

    Counts are the commonest method used to ensure that all sponges and neuropatties are removed from a surgical site before closure. When the count is not reconciled, plain radiographs of the operative site are taken to determine whether the missing patty has been left in the wound. The purpose of this study was to describe the detectability of commonly used neuropatties in the clinical setting using digital technologies. Neuropatties were implanted into the anterior and posterior cranial fossae and the thoracolumbar extradural space of a mature male cadaver. Four neuropatty sizes were used: 3 × 1 in, 2 × ½ in, ½ × ½ in, and ¼ × ¼ in. Neuropatties, with size and location chosen at random, were placed in the surgical sites and anteroposterior/posterior-anterior and lateral radiographs were taken using standard portable digital radiographic equipment. Six clinicians reviewed the digital images for the presence or absence of neuropatties. The readers were not aware of the number and size of the patties that were included in each image. The detectability of neuropatties is dependent on the size of the neuropatty's radiopaque marker and the operative site. Neuropatties measuring 2 × ½ in and 3 × 1 in were detected reliably regardless of the operative site. ¼ × ¼ in neuropatties were poorly detected by neurosurgeons and radiologists in all three operative sites. Readers of various experience and background were similar in their ability to detect neuropatties under these conditions. Under simulated operating room conditions and using currently available neuropatties and plain radiograph imaging technology, small ¼-in and ½-in neuropatties are poorly visible/detectable on digital images. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Improved detection of pulmonary nodules on energy-subtracted chest radiographs with a commercial computer-aided diagnosis software: comparison with human observers

    International Nuclear Information System (INIS)

    Szucs-Farkas, Zsolt; Patak, Michael A.; Yuksel-Hatz, Seyran; Ruder, Thomas; Vock, Peter

    2010-01-01

    To retrospectively analyze the performance of a commercial computer-aided diagnosis (CAD) software in the detection of pulmonary nodules in original and energy-subtracted (ES) chest radiographs. Original and ES chest radiographs of 58 patients with 105 pulmonary nodules measuring 5-30 mm and images of 25 control subjects with no nodules were randomized. Five blinded readers evaluated firstly the original postero-anterior images alone and then together with the subtracted radiographs. In a second phase, original and ES images were analyzed by a commercial CAD program. CT was used as reference standard. CAD results were compared to the readers' findings. True-positive (TP) and false-positive (FP) findings with CAD on subtracted and non-subtracted images were compared. Depending on the reader's experience, CAD detected between 11 and 21 nodules missed by readers. Human observers found three to 16 lesions missed by the CAD software. CAD used with ES images produced significantly fewer FPs than with non-subtracted images: 1.75 and 2.14 FPs per image, respectively (p=0.029). The difference for the TP nodules was not significant (40 nodules on ES images and 34 lesions in non-subtracted radiographs, p = 0.142). CAD can improve lesion detection both on energy subtracted and non-subtracted chest images, especially for less experienced readers. The CAD program marked less FPs on energy-subtracted images than on original chest radiographs. (orig.)

  14. Evaluation of underexposed conventional radiographs after digitization

    International Nuclear Information System (INIS)

    Wenz, W.

    1993-01-01

    Inadequate exposure of analogue radiographs is reported in the literature to occur in 5-25% of cases. Therefore, the present study was performed to test whether selective image processing after digitization could reveal diagnostic details on underexposed radiographs. In addition, the minimal exposure values required for diagnostic purposes after adequate image processing were studied. Phantom studies, organ preparations and measurements of physical parameters with decreasing exposure values were performed. The detection of anatomic and pathologic (nondisplaced fracture lines, microcalcification and renal stones) structures were evaluated by 12 readers. Radiographs with exposure values 20-40% lower than 'ideal' values can provide adequate diagnostic images after digital processing. The diagnostic information is significantly impaired with values under 50% of the correct exposure values. In conclusion, this method is adequate to save underexposed radiographs for diagnostic purposes and to avoid repeated examinations. (orig.) [de

  15. Automating the radiographic NDT process

    International Nuclear Information System (INIS)

    Aman, J.K.

    1988-01-01

    Automation, the removal of the human element in inspection has not been generally applied to film radiographic NDT. The justification for automation is not only productivity but also reliability of results. Film remains in the automated system of the future because of its extremely high image content, approximately 3x10 (to the power of nine) bits per 14x17. This is equivalent to 2200 computer floppy disks parts handling systems and robotics applied for manufacturing and some NDT modalities, should now be applied to film radiographic NDT systems. Automatic film handling can be achieved with the daylight NDT film handling system. Automatic film processing is becoming the standard in industry and can be coupled to the daylight system. Robots offer the opportunity to automate fully the exposure step. Finally, a computer aided interpretation appears on the horizon. A unit which laser scans a 14x27 (inch) film in 6-8 seconds can digitize film in information for further manipulation and possible automatic interrogations (computer aided interpretation). The system called FDRS (for film digital radiography system) is moving toward 50 micron (16 lines/mm) resolution. This is believed to meet the need of the majority of image content needs. (Author). 4 refs.; 21 figs

  16. Computational simulation of radiographic film

    International Nuclear Information System (INIS)

    Goncalves, Elicardo A. de S.; Santos, Marcio H. dos; Anjos, Marcelino J.; Oliveira, Luis F. de

    2013-01-01

    The composition of a radiographic film gives its values of speed, spatial resolution and base density. The technical knowledge allows to predict how a film with a known composition works, and simulate how this film will work with changes in composition and exposure. In this paper, characterization of films composed by different emulsions was realized, in a way to know the characteristic curve, and to study how the format, organization and concentration of silver salt crystals set the radiographic film images.This work aims to increase an existing simulator, where parallel programming was used to simulate X-ray fluorescence processes. The setup of source and X-ray interactions with objects stills the same, and the detector constructed in this work was placed to form images. At first, considering the approach that the film is a square matrix where each element has a specific quantity of silver grains, that each grain fills a specific area, and that each interaction to radiation transforms a salt silver grain in to metallic silver grain (black grain), we have a blackening standard, and it should show how is the behavior of a optic density in a specific area of the film. Each matrix element has a degree of blackening, and it is proportional to the black grains area. (author)

  17. A study on the central plane of image layer in panoramic radiograph

    International Nuclear Information System (INIS)

    Lee, Moon Bai; Park, Chang Seo

    1986-01-01

    The purpose of this investigation was to locate the plane of the image layer on the panoramic machine relative to a specific point on the machine. In the study of the central plane of the image layer of panoramic radiograph, using the Morrita Company PANEX-EC a series of 33 exposures were taken with the 4-5 experimental pins placed in the holes of the plastic model plate, then evaluated by human eye. The author analyzed the central plane of the image layer by Mitutoy-A-221 and calculated horizontal and vertical magnification ratio in central plane of the image layer determined experimentally. The results were as follows: 1. The location of the central plane of the image layer determined experimentally was to lateral compared with manufactural central plane. 2. Horizontal magnification ratio in the central plane of image layer determined experimentally was 9.25%. 3. Vertical magnification ratio in the central plane of the image layer determined experimentally was 9.17%.

  18. Perona Malik anisotropic diffusion model using Peaceman Rachford scheme on digital radiographic image

    International Nuclear Information System (INIS)

    Halim, Suhaila Abd; Razak, Rohayu Abd; Ibrahim, Arsmah; Manurung, Yupiter HP

    2014-01-01

    In image processing, it is important to remove noise without affecting the image structure as well as preserving all the edges. Perona Malik Anisotropic Diffusion (PMAD) is a PDE-based model which is suitable for image denoising and edge detection problems. In this paper, the Peaceman Rachford scheme is applied on PMAD to remove unwanted noise as the scheme is efficient and unconditionally stable. The capability of the scheme to remove noise is evaluated on several digital radiography weld defect images computed using MATLAB R2009a. Experimental results obtained show that the Peaceman Rachford scheme improves the image quality substantially well based on the Peak Signal to Noise Ratio (PSNR). The Peaceman Rachford scheme used in solving the PMAD model successfully removes unwanted noise in digital radiographic image

  19. Perona Malik anisotropic diffusion model using Peaceman Rachford scheme on digital radiographic image

    Energy Technology Data Exchange (ETDEWEB)

    Halim, Suhaila Abd; Razak, Rohayu Abd; Ibrahim, Arsmah [Center of Mathematics Studies, Faculty of Computer and Mathematical Sciences, Universiti Teknologi MARA, 40450 Shah Alam. Selangor DE (Malaysia); Manurung, Yupiter HP [Advanced Manufacturing Technology Excellence Center (AMTEx), Faculty of Mechanical Engineering, Universiti Teknologi MARA, 40450 Shah Alam. Selangor DE (Malaysia)

    2014-06-19

    In image processing, it is important to remove noise without affecting the image structure as well as preserving all the edges. Perona Malik Anisotropic Diffusion (PMAD) is a PDE-based model which is suitable for image denoising and edge detection problems. In this paper, the Peaceman Rachford scheme is applied on PMAD to remove unwanted noise as the scheme is efficient and unconditionally stable. The capability of the scheme to remove noise is evaluated on several digital radiography weld defect images computed using MATLAB R2009a. Experimental results obtained show that the Peaceman Rachford scheme improves the image quality substantially well based on the Peak Signal to Noise Ratio (PSNR). The Peaceman Rachford scheme used in solving the PMAD model successfully removes unwanted noise in digital radiographic image.

  20. [Evaluation method with radiographic image quality indicator for internal defects of dental casting metallic restoration].

    Science.gov (United States)

    Li, Y; Zheng, G; Lin, H

    2014-12-18

    To develop a new kind of dental radiographic image quality indicator (IQI) for internal quality of casting metallic restoration to influence on its usage life. Radiographic image quality indicator method was used to evaluate the depth of the defects region and internal quality of 127 casting metallic restoration and the accuracy was compared with that of conventional callipers method. In the 127 cases of casting metallic restoration, 9 were found the thickness less than 0.7 mm and the thinnest thickness only 0.2 mm in 26 casting metallic crowns or bridges' occlusal defects region. The data measured by image quality indicator were consistent with those measured by conventional gauging. Two metal inner crowns were found the thickness less than 0.3 mm in 56 porcelain crowns or bridges. The thickness of casting removable partial denture was more than 1.0 mm, but thinner regions were not found. It was found that in a titanium partial denture, the X-ray image of clasp was not uniform and there were internal porosity defects in the clasp. Special dental image quality indicator can solve the visual error problems caused by different observing backgrounds and estimate the depth of the defects region in the casting.

  1. Detecting objects in radiographs for homeland security

    Science.gov (United States)

    Prasad, Lakshman; Snyder, Hans

    2005-05-01

    We present a general scheme for segmenting a radiographic image into polygons that correspond to visual features. This decomposition provides a vectorized representation that is a high-level description of the image. The polygons correspond to objects or object parts present in the image. This characterization of radiographs allows the direct application of several shape recognition algorithms to identify objects. In this paper we describe the use of constrained Delaunay triangulations as a uniform foundational tool to achieve multiple visual tasks, namely image segmentation, shape decomposition, and parts-based shape matching. Shape decomposition yields parts that serve as tokens representing local shape characteristics. Parts-based shape matching enables the recognition of objects in the presence of occlusions, which commonly occur in radiographs. The polygonal representation of image features affords the efficient design and application of sophisticated geometric filtering methods to detect large-scale structural properties of objects in images. Finally, the representation of radiographs via polygons results in significant reduction of image file sizes and permits the scalable graphical representation of images, along with annotations of detected objects, in the SVG (scalable vector graphics) format that is proposed by the world wide web consortium (W3C). This is a textual representation that can be compressed and encrypted for efficient and secure transmission of information over wireless channels and on the Internet. In particular, our methods described here provide an algorithmic framework for developing image analysis tools for screening cargo at ports of entry for homeland security.

  2. Effect of display type and room illuminance in chest radiographs

    International Nuclear Information System (INIS)

    Liukkonen, Esa; Jartti, Airi; Haapea, Marianne; Oikarinen, Heljae; Ahvenjaervi, Lauri; Mattila, Seija; Nevala, Terhi; Palosaari, Kari; Perhomaa, Marja; Nieminen, Miika T.

    2016-01-01

    To compare diagnostic accuracy in the detection of subtle chest lesions on digital chest radiographs using medical-grade displays, consumer-grade displays, and tablet devices under bright and dim ambient light. Five experienced radiologists independently assessed 50 chest radiographs (32 with subtle pulmonary findings and 18 without apparent findings) under bright (510 lx) and dim (16 lx) ambient lighting. Computed tomography was used as the reference standard for interstitial and nodular lesions and follow-up chest radiograph for pneumothorax. Diagnostic accuracy and sensitivity were calculated for assessments carried out in all displays and compared using the McNemar test. The level of significance was set to p < 0.05. Significant differences in sensitivity between the assessments under bright and dim lighting were found among consumer-grade displays in interstitial opacities with, and in pneumothorax without, Digital Imaging and Communication in Medicine-Grayscale Standard Display Function (DICOM-GSDF) calibration. Compared to 6 megapixel (MP) display under bright lighting, sensitivity in pneumothorax was lower in the tablet device and the consumer-grade display. Sensitivity in interstitial opacities was lower in the DICOM-GSDF calibrated consumer-grade display. A consumer-grade display with or without DICOM-GSDF calibration or a tablet device is not suitable for reading digital chest radiographs in bright lighting. No significant differences were observed between five displays in dim light. (orig.)

  3. Fatigue stress fractures of the pubic ramus in the army: imaging features with radiographic, scintigraphic and MR imaging findings

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sang Woo; Lee, Chang Hyun [The Armed Forces Capital Hospital, Seongnam (Korea, Republic of)

    2005-03-15

    Although fatigue fractures are not unusual in athletes and military personnel those of the pubic ramus are rare. We report three cases of fatigue fractures of the inferior pubic rami in two male recruits and one female military cadet. On the initial radiograph, most of the lesions were subtle and easy to overlook. However, bone scintigraphy provided more distinct images that allowed easy and early detection of lesion, and MR imaging presented more diagnostic information, which allowed a precise diagnosis.

  4. Impact of lossy compression on diagnostic accuracy of radiographs for periapical lesions

    Science.gov (United States)

    Eraso, Francisco E.; Analoui, Mostafa; Watson, Andrew B.; Rebeschini, Regina

    2002-01-01

    OBJECTIVES: The purpose of this study was to evaluate the lossy Joint Photographic Experts Group compression for endodontic pretreatment digital radiographs. STUDY DESIGN: Fifty clinical charge-coupled device-based, digital radiographs depicting periapical areas were selected. Each image was compressed at 2, 4, 8, 16, 32, 48, and 64 compression ratios. One root per image was marked for examination. Images were randomized and viewed by four clinical observers under standardized viewing conditions. Each observer read the image set three times, with at least two weeks between each reading. Three pre-selected sites per image (mesial, distal, apical) were scored on a five-scale score confidence scale. A panel of three examiners scored the uncompressed images, with a consensus score for each site. The consensus score was used as the baseline for assessing the impact of lossy compression on the diagnostic values of images. The mean absolute error between consensus and observer scores was computed for each observer, site, and reading session. RESULTS: Balanced one-way analysis of variance for all observers indicated that for compression ratios 48 and 64, there was significant difference between mean absolute error of uncompressed and compressed images (P <.05). After converting the five-scale score to two-level diagnostic values, the diagnostic accuracy was strongly correlated (R (2) = 0.91) with the compression ratio. CONCLUSION: The results of this study suggest that high compression ratios can have a severe impact on the diagnostic quality of the digital radiographs for detection of periapical lesions.

  5. Advanced and extended scope practice of diagnostic radiographers in Scotland: Exploring strategic imaging service imperatives.

    Science.gov (United States)

    Henderson, I; Mathers, S A; McConnell, J

    2017-08-01

    The development of diagnostic imaging services manifests features specific to the Scottish environment, in particular development of the radiographic workforce through implementing skills mix and role developments to enhance outcomes for patients. A component of a College of Radiographers Industry Partnership Scheme (CoRIPS) supported study, this research investigates perspectives of strategic service managers with Health Board responsibility for service delivery. A questionnaire survey was administered to strategic service managers across Scotland (N = 14), followed up with telephone interviews. There was a return rate of 57% (n = 8) for the questionnaires and n = 4 agreed to be interviewed. Data collected related to radiographer roles across their Board area; awareness and understanding of service development issues and features as well as perspective on opportunities and barriers in the context of Scottish Government policy, workforce logistics, attitudes and inter-professional relationships. The results indicate evidence of financial, logistical and political barriers to service evolution, offset by a sense of optimism that scope for beneficial change may be approaching. There are a range of significant initiatives in place and an appetite exists to pursue the development of radiographer roles and skill mix for the benefit of service users more generally. The difficulties in achieving change are well understood and there are basic issues related to finance and industrial relations. There are also however, cultural elements to contend with in the form of attitudes demonstrated by some radiographers and significantly, the radiological community whose influence on the practice of independently regulated radiographers seems incongruent. Copyright © 2017 The College of Radiographers. Published by Elsevier Ltd. All rights reserved.

  6. Personalized models of bones based on radiographic photogrammetry.

    Science.gov (United States)

    Berthonnaud, E; Hilmi, R; Dimnet, J

    2009-07-01

    The radiographic photogrammetry is applied, for locating anatomical landmarks in space, from their two projected images. The goal of this paper is to define a personalized geometric model of bones, based uniquely on photogrammetric reconstructions. The personalized models of bones are obtained from two successive steps: their functional frameworks are first determined experimentally, then, the 3D bone representation results from modeling techniques. Each bone functional framework is issued from direct measurements upon two radiographic images. These images may be obtained using either perpendicular (spine and sacrum) or oblique incidences (pelvis and lower limb). Frameworks link together their functional axes and punctual landmarks. Each global bone volume is decomposed in several elementary components. Each volumic component is represented by simple geometric shapes. Volumic shapes are articulated to the patient's bone structure. The volumic personalization is obtained by best fitting the geometric model projections to their real images, using adjustable articulations. Examples are presented to illustrating the technique of personalization of bone volumes, directly issued from the treatment of only two radiographic images. The chosen techniques for treating data are then discussed. The 3D representation of bones completes, for clinical users, the information brought by radiographic images.

  7. Radiographic landmarks for locating the femoral origin of the superficial medial collateral ligament.

    Science.gov (United States)

    Hartshorn, Timothy; Otarodifard, Karimdad; White, Eric A; Hatch, George F Rick

    2013-11-01

    Little has been written about the use of radiographic landmarks for locating the origin of the superficial medial collateral ligament (sMCL). A standardized radiographic landmark for the sMCL origin using intraoperative fluoroscopic imaging may be of value in aiding the surgeon in accurate femoral tunnel placement in the setting of extensive soft tissue disruption and bony attrition. To determine a reproducible radiographic landmark that will assist in correct femoral tunnel placement in sMCL repair and reconstruction. Descriptive laboratory study. Ten fresh-frozen unmatched human cadaveric knees were dissected, and the origin of the sMCL was exposed. A 2-mm metallic marker was then placed at the center of the femoral origin of the sMCL. True lateral fluoroscopically assisted digital radiographs were obtained of the knee with the posterior and distal femoral condyles overlapping in a standardized fashion. With the use of computer software, reference lines were drawn on the images, creating 4 quadrants. Two independent examiners performed quantitative measurements of the sMCL origin in relation to this axis and to the Blumensaat line. Mean measurements showed the sMCL origin to be closely related to the intersection point of the Blumensaat line and a line drawn distally from the posterior femoral cortex on a true lateral radiograph. The sMCL origin was found at a mean point 1.6 ± 4.3 mm posterior and 4.9 ± 2.1 mm proximal to the intersection of a line paralleling the posterior femoral cortex and a line drawn perpendicular to the posterior femoral cortical line, where it intersects the Blumensaat line. In 5 of 10 specimens, the center of the sMCL origin fell precisely on the Blumensaat line. The remaining specimens had sMCL origins anterior to the Blumensaat line. The femoral origin of the sMCL was found in the proximal and posterior quadrants in 8 of 10 specimens. With a relatively small amount of deviation, the sMCL origin can be consistently identified on a true

  8. Radiographic evaluation of coxofemoral joint laxity in dogs part II: Comparison of stress-radiographic positioning techniques in dogs with hip dysplasia

    International Nuclear Information System (INIS)

    Duangdaun Kaenkangploo; Phiwipha Kamonrat; Marissak Kalpravidh

    2002-01-01

    Two stress-radiographic positioning techniques for evaluation of coxofemoral joint laxity in dogs with hip dysplasia were compared with the standard technique. Forty, healthy, large breed dogs were divided into two groups of 20 dogs. Group 1 had normal hips. Group 2 were dogs with mild to moderated grade of hip dysplasia according to the Orthopedic Foundation for Animals (OFA) standard. Dogs were anesthetized and placed in dorsal recumbency before 3 radiographic techniques, standard hip-extended, 60 deg and 90 deg stress techniques, were taken. For the 60 deg stress technique, hind legs were extended in parallel to each other at 60 deg to the table top and femoral heads were manually pushed craniodorsally during exposure. For the 90 deg stress technique, femurs were positioned perpendicular to the table top, stifles were 90 deg flexed and adducted and femoral heads were manually pushed in a craniodorsal direction during exposure. Subluxation index (SI) and dorsolateral subluxation score (DLS score) of coxofemoral joints were assessed from radiographs. The SI of normal dogs from standard, 60 deg and 90 deg stress techniques were 0.15, 0.20 and 0.23 and of dysplastic dogs were 0.34, 0.40 and 0.41 respectively. The degress of subluxation assessed from the two stress technique radiographs were significantly greater (p0.05) than those shown on the standard technique radiographs in both groups of dogs. DLS scores of normal dogs from standard, 60 deg and 90 deg stress techniques were 65.1, 64.3 and 61.0 percent and of dysplastic dogs were 55.4, 53.6 and 47.6 percent respectively. Mean of DLS scores assessed from the 90 deg radiographs was significantly lower (p0.05) than those assessed from radiographs of other two teachniques in both groups of dogs. The findings suggested that the 90 deg stress technique is more efficient than the standard and 60 deg stress techniques for radiographic evaluation of coxofemoral joint laxity in dogs with mild hip dysplasia and early

  9. Optic densitometry in radiographic images to evaluate nutritional secondary hyperparathyroidism in kittens

    International Nuclear Information System (INIS)

    Rahal, S.C.; Mortari, A.C.; Caporali, E.H.G.; Vulcano, L.C.; Santos, F.A.M. dos; Takahira, R.K.; Crocci, A.J.

    2002-01-01

    The aim of this study was to evaluate the modification of bone mineral density, as well as the serum biochemistry variation in the nutritional secondary hyperparathyroidism. Ten crossbreed cats, initial aging between 2 and 3 months, and weighing 820 grams were used. After 10 days of adaptation, they were fed with raw beef heart for 60 days. At the end of adaptation time and every 15 days, exams were realized. The method of optical densitometry in radiographic images of the right radius and ulna was used. There was no statistical difference in the bone mineral densitometry between the end of adaptation period and with 15 days of consuming a diet of beef heart. At 30 days the bone density decreased statistically, and it was in the same level at 45 and 60 days. There was no statistical difference in the serum calcium and phosphorus concentrations in all observation time. Serum alkaline phosphatase concentration varied and it was increased above normal variation in the 45 th and 60 th day of the diet. It was possible to conclude that bone densitometry in radiographic images is an efficient method to evaluate bone demineralization, and calcium, phosphorus and alkaline phosphatase serum biochemistry analysis are limited value [pt

  10. Radiographic visualization of magma dynamics in an erupting volcano.

    Science.gov (United States)

    Tanaka, Hiroyuki K M; Kusagaya, Taro; Shinohara, Hiroshi

    2014-03-10

    Radiographic imaging of magma dynamics in a volcanic conduit provides detailed information about ascent and descent of magma, the magma flow rate, the conduit diameter and inflation and deflation of magma due to volatile expansion and release. Here we report the first radiographic observation of the ascent and descent of magma along a conduit utilizing atmospheric (cosmic ray) muons (muography) with dynamic radiographic imaging. Time sequential radiographic images show that the top of the magma column ascends right beneath the crater floor through which the eruption column was observed. In addition to the visualization of this magma inflation, we report a sequence of images that show magma descending. We further propose that the monitoring of temporal variations in the gas volume fraction of magma as well as its position in a conduit can be used to support existing eruption prediction procedures.

  11. Radiographic examination takes on an automated image

    International Nuclear Information System (INIS)

    Aman, J.

    1988-01-01

    Automation can be effectively applied to nondestructive testing (NDT). Until recently, film radiography used in NDT was largely a manual process, involving the shooting of a series of x-rays, manually positioned and manually processed. In other words, much radiographic work is being done the way it was over 50 years ago. Significant advances in automation have changed the face of manufacturing, and industry has shared in the benefits brought by such progress. The handling of parts, which was once responsible for a large measure of labor costs, is now assigned to robotic equipment. In nondestructive testing processes, some progress has been achieved in automation - for example, in real-time imaging systems. However, only recently have truly automated NDT begun to emerge. There are two major reasons to introduce automation into NDT - reliability and productivity. Any process or technique that can improve the reliability of parts testing could easily justify the capital investments required

  12. Statistical shape model-based reconstruction of a scaled, patient-specific surface model of the pelvis from a single standard AP x-ray radiograph

    Energy Technology Data Exchange (ETDEWEB)

    Zheng Guoyan [Institute for Surgical Technology and Biomechanics, University of Bern, Stauffacherstrasse 78, CH-3014 Bern (Switzerland)

    2010-04-15

    Purpose: The aim of this article is to investigate the feasibility of using a statistical shape model (SSM)-based reconstruction technique to derive a scaled, patient-specific surface model of the pelvis from a single standard anteroposterior (AP) x-ray radiograph and the feasibility of estimating the scale of the reconstructed surface model by performing a surface-based 3D/3D matching. Methods: Data sets of 14 pelvises (one plastic bone, 12 cadavers, and one patient) were used to validate the single-image based reconstruction technique. This reconstruction technique is based on a hybrid 2D/3D deformable registration process combining a landmark-to-ray registration with a SSM-based 2D/3D reconstruction. The landmark-to-ray registration was used to find an initial scale and an initial rigid transformation between the x-ray image and the SSM. The estimated scale and rigid transformation were used to initialize the SSM-based 2D/3D reconstruction. The optimal reconstruction was then achieved in three stages by iteratively matching the projections of the apparent contours extracted from a 3D model derived from the SSM to the image contours extracted from the x-ray radiograph: Iterative affine registration, statistical instantiation, and iterative regularized shape deformation. The image contours are first detected by using a semiautomatic segmentation tool based on the Livewire algorithm and then approximated by a set of sparse dominant points that are adaptively sampled from the detected contours. The unknown scales of the reconstructed models were estimated by performing a surface-based 3D/3D matching between the reconstructed models and the associated ground truth models that were derived from a CT-based reconstruction method. Such a matching also allowed for computing the errors between the reconstructed models and the associated ground truth models. Results: The technique could reconstruct the surface models of all 14 pelvises directly from the landmark

  13. Radiographers' and radiology practitioners' opinion, experience and practice of benefit-risk communication and consent in paediatric imaging

    International Nuclear Information System (INIS)

    Portelli, J.L.; McNulty, J.P.; Bezzina, P.; Rainford, L.

    2016-01-01

    Objectives: To investigate radiographers' and radiology practitioners' opinion, experience and practice of radiation benefit-risk communication and consent for paediatric imaging examinations. Methods: A cross-sectional survey was conducted amongst radiographers and radiology practitioners working at a primary paediatric referral centre in Malta, so as to acquire information about their interactions with paediatric patients and/or their parents, particularly their opinion and practice of communicating benefit-risk information and seeking consent for imaging examinations. Results: The return of 112 questionnaires provided a response rate of 66.7%. Findings revealed varied practice relating to the provision of benefit-risk information, whereby details concerning examination benefits and potential risks are not always conveyed. For 89% of participants, parental consent was sought for paediatric imaging examinations in their current practice. Only 36.7% of participants indicated that they were highly confident in their ability to communicate benefit-risk information. The study findings also revealed that parents can truly be worried about the associated radiation exposure, with some even refusing an imaging examination as a result of such concerns. Conclusions: The practice of communicating benefit-risk information to paediatric patients and/or their parents is varied. A possible gap in benefit-risk communication education and/or training was identified, which may impact radiographers' and radiology practitioners' confidence in conveying such information. Education/training activities for radiographers and radiology practitioners are therefore necessary to foster improved benefit-risk dialogues and help provide reassurance to parents/guardians about the benefits of appropriately indicated paediatric imaging examinations. - Highlights: • The practice of communicating radiation benefit-risk information to parents of paediatric patients is varied.

  14. Endodontic radiography: who is reading the digital radiograph?

    Science.gov (United States)

    Tewary, Shalini; Luzzo, Joseph; Hartwell, Gary

    2011-07-01

    Digital radiographic imaging systems have undergone tremendous improvements since their introduction. Advantages of digital radiographs over conventional films include lower radiation doses compared with conventional films, instantaneous images, archiving and sharing images easily, and manipulation of several radiographic properties that might help in diagnosis. A total of 6 observers including 2 endodontic residents, 3 endodontists, and 1 oral radiologist evaluated 150 molar digital periapical radiographs to determine which of the following conditions existed: normal periapical tissue, widened periodontal ligament, or presence of periapical radiolucency. The evaluators had full control over the radiograph's parameters of the Planmeca Dimaxis software program. All images were viewed on the same computer monitor with ideal vie-wing conditions. The same 6 observers evaluated the same 150 digital images 3 months later. The data were analyzed to determine how well the evaluators agreed with each other (interobserver agreement) for 2 rounds of observations and with themselves (intraobserver agreement). Fleiss kappa statistical analysis was used to measure the level of agreement among multiple raters. The overall Fleiss kappa value for interobserver agreement for the first round of interpretation was 0.34 (P value for interobserver agreement for the second round of interpretation was 0.35 (P fair (0.2-0.4) agreement among the 6 raters at both observation periods. A weighted kappa analysis was used to determine intraobserver agreement, which showed on average a moderate agreement. The results indicate that the interpretation of a dental radiograph is subjective, irrespective of whether conventional or digital radiographs are used. The factors that appeared to have the most impact were the years of experience of the examiner and familiarity of the operator with a given digital system. Copyright © 2011 American Association of Endodontists. Published by Elsevier Inc. All

  15. Internet-accessible radiographic database of Vietnam War casualties for medical student education.

    Science.gov (United States)

    Critchley, Eric P; Smirniotopoulos, James G

    2003-04-01

    The purpose of this study was to determine the feasibility of archiving radiographic images from Vietnam era conflict casualties into a personal computer-based electronic database of text and images and displaying the data using an Internet-accessible database for preservation and educational purposes. Thirty-two patient cases were selected at random from a pool of 1,000 autopsy reports in which radiographs were available. A total of 74 radiographs from these cases were digitized using a commercial image scanner and then uploaded into an Internet accessible database. The quality of the digitized images was assessed by administering an image-based test to a group of 12 medical students. No statistically significant (p > 0.05) differences were found between test scores when using the original radiographs versus using the digitized radiographs on the Internet-accessible database. An Internet-accessible database is capable of effectively archiving Vietnam era casualty radiographs for educational purposes.

  16. Computer-aided diagnosis of pneumoconiosis abnormalities extracted from chest radiographs scanned with a CCD scanner

    International Nuclear Information System (INIS)

    Abe, Koji; Minami, Masahide; Nakamura, Munehiro

    2011-01-01

    This paper presents a computer-aided diagnosis for pneumoconiosis radiographs obtained with a common charge-coupled devices (CCD) scanner. Since the current computer-aided diagnosis systems of pneumoconiosis are not practical for medical doctors due to high costs of usage for a special scanner, we propose a novel system which measures abnormalities of pneumoconiosis from lung images obtained with a common CCD scanner. Experimental results of discriminations between normal and abnormal cases for 56 right-lung images including 6 standard pneumoconiosis images have shown that the proposed abnormalities are well extracted according to the standards of pneumoconiosis categories. (author)

  17. Topical issues of radiographic testing and radiation protection. Papers

    International Nuclear Information System (INIS)

    1992-01-01

    The seven papers demonstrate current developments in radiation protection. The amendment of the Radiation Protection Ordinance and the new Ordinance on the Transport of Hazardous Goods by Road were discussed in particular. A major results of the discussion meeting was the foundation of the working group on 'Transport of radioactive substances'. In terms of radiographic practive, the authors addressed European standardization, instruments and technology in radioscopy, and computer-aided image processing. (orig./HP) [de

  18. A neural network approach for radiographic image classification in NDT

    International Nuclear Information System (INIS)

    Lavayssiere, B.

    1993-05-01

    Radiography is used by EDF for pipe inspection in nuclear power plants in order to detect defects. The radiographs obtained are then digitized in a well-defined protocol. The aim of EDF consists of developing a non destructive testing system for recognizing defects. In this note, we describe the recognition procedure of areas with defects. We first present the digitization protocol, specifies the poor quality of images under study and propose a procedure to enhance defects. We then examine the problem raised by the choice of good features for classification. After having proved that statistical or standard textural features such as homogeneity, entropy or contrast are not relevant, we develop a geometrical-statistical approach based on the cooperation between signal correlations study and regional extrema analysis. The principle consists of analysing and comparing for areas with defects and without any defect, the evolution of conditional probabilities matrices for increasing neighbourhood sizes, the shape of variograms and the location of regional minima. We demonstrate that anisotropy and surface of series of 'comet tails' associated with probability matrices, variograms slope and statistical indices, regional extrema location, are features able to discriminate areas with defects from areas without any. The classification is then realized by a neural network, which structure, properties and learning mechanisms are detailed. Finally we discuss the results. (author). 5 figs., 21 refs

  19. The diagnosis of small solitary pulmonary nodule: comparison of standard and inverse digital images on a high resolution monitor using ROC analysis

    International Nuclear Information System (INIS)

    Choi, Byeong Kyoo; Lee, In Sun; Seo, Joon Beom; Lee, Jin Seong; Song, Koun Sik; Lim, Tae Hwan

    2002-01-01

    To study the impact of inversion of soft-copy chest radiographs on the detection of small solitary pulmonary nodules using a high-resolution monitor. The study group consisted of 80 patients who had undergone posterior chest radiography; 40 had a solitary noncalcified pulmonary nodule approximately 1 cm in diameter, and 40 were control subjects. Standard and inverse digital images using the inversion tool on a PACS system were displayed on high-resolution monitors (2048x2560x8 bit). Ten radiologists were requested to rank each image using a five-point scale (1=definitely negative, 3=equivocal or indeterminate, 5=definite nodule), and the data were interpreted using receiver operating characteristic (ROC) analysis. The area under the ROC curve for pooled data of standard image sets was significantly larger than that of inverse image sets (0.8893 and 0.8095, respectively; p 0.05). For detecting small solitary pulmonary nodules, inverse digital images were significantly inferior to standard digital images

  20. Neonates do not need to be handled for radiographs

    International Nuclear Information System (INIS)

    Slade, Dawn; Alfaham, Mazin; Davis, Peter; Tuthill, David; Harrison, Sara; Morris, Susan; Guildea, Zoe

    2005-01-01

    The handling of sick neonates may have detrimental effects such as hypoxia or bradycardia. Such handling is inevitable due to the frequent need for practical procedures; however, minimising handling reduces these adverse events and may improve outcome. Radiography is one of the commonest procedures performed on neonates. Usually the infant is lifted and placed onto the radiographic cassette; however, modern incubators often incorporate a tray beneath the mattress in which the radiographic cassette can be placed without the need to disturb the infant. To compare the quality of chest radiographs taken using the standard direct contact method, with those taken using the under-tray technique. A series of chest radiographs taken over a 21-month period were analysed independently by two consultant paediatric radiologists unaware of the radiographic details. The position of the radiograph, i.e. direct contact or under-tray, was determined by the radiographer. Radiographic quality was scored on the following features: exposure, blurring, rotation, cut-off or coning, and side markers. A subjective score was also included. The results from each radiologist were analysed separately. Seventy chest radiographs were analysed - 25 standard method, 45 under-tray. A statistically significant advantage for the under-tray method was seen on two analyses - radiologist 1 for exposure, and radiologist 2 for cut-off. No other significant differences were noted. There were no differences in the infants' weights or radiation exposure. The under-tray method for taking radiographs may produce films of at least equivalent quality to the standard method. Since the standard method involves handling with potential desaturation and bradycardia, this technique should cease. (orig.)

  1. Radiographic evaluation of dentigerous cyst with cone beam CT

    International Nuclear Information System (INIS)

    Park, Yong Chan; Lee, Wan; Lee, Byung Do

    2010-01-01

    The purpose of this study was to accurately analyze the radiographic characteristics of dentigerous cyst (DC) with multiplanar images of cone beam computed tomography (CBCT). Thirty eight radiographically and histopathologically proven cases of DCs were analyzed with panoramic radiograph and CBCT, retrospectively. The radiographic CT pattern, symmetry of radiolucency around the unerupted tooth crown, ratio of long length to short length, degree of cortical bone alternation, effects on adjacent tooth, and cyst size were analyzed. Relative frequencies of these radiographic features were evaluated. In order to compare the CBCT features of DC with those of odontogenic keratocyst (OKC), 9 cases of OKCs were analyzed with the same method radiographically. DCs consisted of thirty unilocular cases (79.0%), seven lobulated cases (18.4%) and one multilocular case (2.6%). Eight were asymmetric (21.0%) and thirty were symmetric (79.0%). Maxillary DC showed rounder shape than mandibular DC (L/S ratio; maxilla 1.32, mandible 1.67). Alternations of lingual cortical bone (14 cases, 48.2%) were more frequent than those of buccal side (7 cases, 24.1%). CBCT images of DC showed definite root resorption and bucco-lingual tooth displacement. These findings were hardly observed on panoramic radiographs of DCs. Comparison of CBCT features of DC with those of OKC showed several different features. CBCT images of DC showed various characteristic radiographic features. Therefore, CBCT can be helpful for the diagnosis of DC radiographically.

  2. Radiographic evaluation of dentigerous cyst with cone beam CT

    Energy Technology Data Exchange (ETDEWEB)

    Park, Yong Chan; Lee, Wan; Lee, Byung Do [School of Dentisity, Wonkwang University, Iksan (Korea, Republic of)

    2010-09-15

    The purpose of this study was to accurately analyze the radiographic characteristics of dentigerous cyst (DC) with multiplanar images of cone beam computed tomography (CBCT). Thirty eight radiographically and histopathologically proven cases of DCs were analyzed with panoramic radiograph and CBCT, retrospectively. The radiographic CT pattern, symmetry of radiolucency around the unerupted tooth crown, ratio of long length to short length, degree of cortical bone alternation, effects on adjacent tooth, and cyst size were analyzed. Relative frequencies of these radiographic features were evaluated. In order to compare the CBCT features of DC with those of odontogenic keratocyst (OKC), 9 cases of OKCs were analyzed with the same method radiographically. DCs consisted of thirty unilocular cases (79.0%), seven lobulated cases (18.4%) and one multilocular case (2.6%). Eight were asymmetric (21.0%) and thirty were symmetric (79.0%). Maxillary DC showed rounder shape than mandibular DC (L/S ratio; maxilla 1.32, mandible 1.67). Alternations of lingual cortical bone (14 cases, 48.2%) were more frequent than those of buccal side (7 cases, 24.1%). CBCT images of DC showed definite root resorption and bucco-lingual tooth displacement. These findings were hardly observed on panoramic radiographs of DCs. Comparison of CBCT features of DC with those of OKC showed several different features. CBCT images of DC showed various characteristic radiographic features. Therefore, CBCT can be helpful for the diagnosis of DC radiographically.

  3. Small lung cancers: improved detection by use of bone suppression imaging--comparison with dual-energy subtraction chest radiography.

    Science.gov (United States)

    Li, Feng; Engelmann, Roger; Pesce, Lorenzo L; Doi, Kunio; Metz, Charles E; Macmahon, Heber

    2011-12-01

    To determine whether use of bone suppression (BS) imaging, used together with a standard radiograph, could improve radiologists' performance for detection of small lung cancers compared with use of standard chest radiographs alone and whether BS imaging would provide accuracy equivalent to that of dual-energy subtraction (DES) radiography. Institutional review board approval was obtained. The requirement for informed consent was waived. The study was HIPAA compliant. Standard and DES chest radiographs of 50 patients with 55 confirmed primary nodular cancers (mean diameter, 20 mm) as well as 30 patients without cancers were included in the observer study. A new BS imaging processing system that can suppress the conspicuity of bones was applied to the standard radiographs to create corresponding BS images. Ten observers, including six experienced radiologists and four radiology residents, indicated their confidence levels regarding the presence or absence of a lung cancer for each lung, first by using a standard image, then a BS image, and finally DES soft-tissue and bone images. Receiver operating characteristic (ROC) analysis was used to evaluate observer performance. The average area under the ROC curve (AUC) for all observers was significantly improved from 0.807 to 0.867 with BS imaging and to 0.916 with DES (both P chest radiographs. Further improvements can be achieved by use of DES radiography but with the requirement for special equipment and a potential small increase in radiation dose. © RSNA, 2011.

  4. Agreement between radiographic and photographic trabecular patterns

    Energy Technology Data Exchange (ETDEWEB)

    Korstjens, C.M.; Geraets, W.G.M.; Stelt, P.F. van der [Dept. of Oral Radiology, Academic Centre for Dentistry, Amsterdam (Netherlands); Spruijt, R.J. [Div. of Psychosocial Research and Epidemiology, Netherlands Cancer Inst., Amsterdam (Netherlands); Mosekilde, L. [Dept. of Cell Biology, Univ. of Aarhus (Denmark)

    1998-11-01

    Purpose: It has been hypothesized that photographs can facilitate the interpretation of the radiographic characteristics of trabecular bone. The reliability of these photographic and radiographic approaches has been determined, as have various agreements between the two approaches and their correlations with biomechanical characteristics. Material and Methods: Fourteen vertebral bodies were obtained at autopsy from 6 women and 8 men aged 22-76 years. Photographs (n=28) and radiographs (n=28) were taken of midsagittal slices from the third lumbar vertebra. The radiographs and photographs were digitized and the geometric properties of the trabecular architecture were then determined with a digital images analysis technique. Information on the compressive strength and ash density of the vertebral body was also available. Results: The geometric properties of both radiographs and photographs could be measured with a high degree of reliability (Cronbach`s {alpha}>0.85). Agreement between the radiographic and photographic approaches was mediocre as only the radiographic measurements showed insignificant correlations (p<0.05) with the biomechanical characteristics. We suggest that optical phenomena may result in the significant correlations between the photographs and the biomechanical characteristics. Conclusion: For digital image processing, radiography offers a superior description of the architecture of trabecular bone to that offered by photography. (orig.)

  5. Agreement between radiographic and photographic trabecular patterns

    International Nuclear Information System (INIS)

    Korstjens, C.M.; Geraets, W.G.M.; Stelt, P.F. van der; Spruijt, R.J.; Mosekilde, L.

    1998-01-01

    Purpose: It has been hypothesized that photographs can facilitate the interpretation of the radiographic characteristics of trabecular bone. The reliability of these photographic and radiographic approaches has been determined, as have various agreements between the two approaches and their correlations with biomechanical characteristics. Material and Methods: Fourteen vertebral bodies were obtained at autopsy from 6 women and 8 men aged 22-76 years. Photographs (n=28) and radiographs (n=28) were taken of midsagittal slices from the third lumbar vertebra. The radiographs and photographs were digitized and the geometric properties of the trabecular architecture were then determined with a digital images analysis technique. Information on the compressive strength and ash density of the vertebral body was also available. Results: The geometric properties of both radiographs and photographs could be measured with a high degree of reliability (Cronbach's α>0.85). Agreement between the radiographic and photographic approaches was mediocre as only the radiographic measurements showed insignificant correlations (p<0.05) with the biomechanical characteristics. We suggest that optical phenomena may result in the significant correlations between the photographs and the biomechanical characteristics. Conclusion: For digital image processing, radiography offers a superior description of the architecture of trabecular bone to that offered by photography. (orig.)

  6. Low molecular weight dextran provides similar optical coherence tomography coronary imaging compared to radiographic contrast media.

    Science.gov (United States)

    Frick, Kyle; Michael, Tesfaldet T; Alomar, Mohammed; Mohammed, Atif; Rangan, Bavana V; Abdullah, Shuaib; Grodin, Jerrold; Hastings, Jeffrey L; Banerjee, Subhash; Brilakis, Emmanouil S

    2014-11-01

    Optical coherence tomography (OCT) coronary imaging requires displacement of red blood cells from the vessel lumen. This is usually accomplished using radiographic contrast. Low molecular weight dextran has low cost and is safe in low volumes. In the present study, we compared dextran with contrast for coronary OCT imaging. Fifty-one vessels in 26 patients were sequentially imaged using manual injection of radiographic contrast (iodixanol) and dextran. OCT images were analyzed at 1 mm intervals to determine the image clarity (defined as a visible lumen border > 270°) and to measure the lumen area and lumen diameter. To correct for the refractive index of dextran, the dextran area measurements were multiplied by 1.117 and the dextran length measurements were multiplied by 1.057. A total of 3,418 cross-sections (1,709 with contrast and 1,709 with dextran) were analyzed. There were no complications related to OCT imaging or to contrast or dextran administration. Clear image segments were observed in 97.0% vs. 96.7% of the cross-sections obtained with contrast and dextran, respectively (P = 0.45). The mean lumen areas were also similar: 6.69 ± 1.95 mm(2) with iodixanol vs. 7.06 ± 2.06 mm(2) with dextran (correlation coefficient 0.984). The image quality and measurements during OCT image acquisition are similar for dextran and contrast. Dextran could be used instead of contrast for OCT imaging, especially in patients in whom contrast load minimization is desired. © 2013 Wiley Periodicals, Inc.

  7. Clinical and Plain Radiograph Pattern of Joint Dislocations and ...

    African Journals Online (AJOL)

    Plain radiograph is an integral part of early assessment of patients' evaluation, though newer imaging modalities such as magnetic resonance imaging (MRI), ... Conclusion: The shoulder joint is the most frequently dislocated and a conventional plain radiograph is still valuable as a first line investigative modality in ...

  8. Imaging standards for smart cards

    Science.gov (United States)

    Ellson, Richard N.; Ray, Lawrence A.

    1996-02-01

    "Smart cards" are plastic cards the size of credit cards which contain integrated circuits for the storage of digital information. The applications of these cards for image storage has been growing as card data capacities have moved from tens of bytes to thousands of bytes. This has prompted the recommendation of standards by the X3B10 committee of ANSI for inclusion in ISO standards for card image storage of a variety of image data types including digitized signatures and color portrait images. This paper will review imaging requirements of the smart card industry, challenges of image storage for small memory devices, card image communications, and the present status of standards. The paper will conclude with recommendations for the evolution of smart card image standards towards image formats customized to the image content and more optimized for smart card memory constraints.

  9. Reporting by radiographers: a policy and practice guide

    International Nuclear Information System (INIS)

    Paterson, Audrey M.; Price, Richard C.; Thomas, Adrian; Nuttall, Lorraine

    2004-01-01

    Reporting by radiographers and other non-medical staff has developed considerably in the past decade, and especially so since the College of Radiographers published its vision paper on reporting by radiographers, in 1997. It was felt necessary, therefore, to develop guidance to assist radiographers and others undertaking radiographic reporting. The guidance provided includes guidance on planning and implementing a reporting service using reporting radiographers; the education, continuing education and support required by reporting radiographers; quality and standards related to reporting; and the nature of a report. Broader issues that will need to be addressed as reporting by radiographers becomes the norm are also raised

  10. Subtraction radiography and computer assisted densitometric analyses of standardized radiographs. A comparison study with /sup 125/I absorptiometry

    Energy Technology Data Exchange (ETDEWEB)

    Ortmann, L.F.; Dunford, R.; McHenry, K.; Hausmann, E.

    1985-01-01

    A standardized radiographic series of incrementally increasing alveolar crestal defects in skulls were subjected to analyses by subtraction radiography and computer assisted quantitative densitometric analysis. Subjects were able to detect change using subtraction radiography in alveolar bone defects with bone loss in the range of 1-5 percent as measured by /sup 125/I absorptiometry. Quantitative densitometric analyses utilizing radiographic pairs adjusted for differences in contrast (gamma corrected) can be used to follow longitudinal changes at a particular alveolar bone site. Such measurements correlate with change observed by /sup 125/I absorptiometry (r=0.82-0.94). (author).

  11. Spectrum of Inflammatory Changes in the SIJs on Radiographs and MR Images in Patients with Suspected Axial Spondyloarthritis

    International Nuclear Information System (INIS)

    Sudoł-Szopińska, Iwona; Włodkowska-Korytkowska, Monika; Kwiatkowska, Brygida

    2016-01-01

    The aim of the paper was to compare radiographs and MRI in assessment of active and chronic inflammatory changes in the sacroiliac joints in patients with chronic back pain and suspected axial spondyloarthritis. Moreover, the aim was to determine which of the two methods is more accurate in diagnosing individual inflammatory changes in the sacroiliac joints and whether there is a correlation between radiographs and MRI in their identification. The analysis was conducted in a group of 101 patients, including 61 women and 40 men, referred to radiographs and MR examinations by rheumatologists due to chronic back pain. AP images of the lumbar region of the spine were performed in each patient in the supine position. The images included the sacroiliac joints. Changes in the SIJs were assessed based on the New York criteria of 1966. In MR examination, the SIJs were assessed in terms of the presence of active and chronic inflammatory changes described by the ASAS. The statistical analysis of the variables tested was conducted in the Excel and Statistica systems. In relation to the final clinical diagnosis of axSpA, MRI had higher sensitivity and specificity than radiography in diagnosing sacroiliitis (sensitivity: 71% vs. 22%, specificity: 90% vs. 94% on radiographs according to New York criteria. In relation to MRI, radiographs resulted in 40% of incorrect sacroiliitis diagnoses (both false positive and false negative results). In as many as 50% of cases (7/14), MRI failed to confirm the presence of inflammatory changes in the sacroiliac joints observed in radiography according to the modNY criteria (false positive results on radiographs). Both examinations are characterised by very low agreement, which is near to random, in assessing individual features of sacroiliitis, such as sclerosis, change in the joint space width, erosions and ankylosis. 1. Radiographs do not allow early inflammatory lesions indicating sacroiliitis to be diagnosed, which leads to diagnostic delay

  12. Comparison of different radiographic methods for the detection of the mandibular canal

    International Nuclear Information System (INIS)

    Kim, Eun Kyung

    2003-01-01

    To compare the visibility of the mandibular canal at the different radiographic methods such as conventional panoramic radiographs, Vimplant multiplanar reformatting (MPR)-CT panoramic images, Vimplant MPR-CT paraxial images and film-based DentaScan MPR-CT images. Data of 11 mandibular dental implant patients, who had been planned treatment utilizing both panoramic and MPR-CT examination with DentaScan software (GE Medical systems, Milwaukee, USA), were used in this study. The archived axial CT data stored on CD-R discs were transferred to a personal computer with 17' LCD monitor. Paraxial and panoramic images were reconstructed using Vimplant software (CyberMed Inc., Seoul, Korea). Conventional panoramic radiographs, monitor-based Vimplant MPR-CT panoramic images, monitor-based Vimplant MPR-CT paraxial images, and film-based DentaScan MPR-CT images were evaluated for visibility of the mandibular canal at the mental foramen, 1 cm, 2 cm, and 3 cm posterior to mental foramen using the 4-point grading score. Vimplant MPR-CT panoramic, paraxial, and DentaScan MPR-CT images revealed significantly clearer images than conventional panoramic radiographs. Particularly at the region 1 cm posterior to mental foramen, conventional panoramic radiographs showed a markedly lower percentage of 'excellent' mandibular canal images than images produced by other modalities. Vimplant MPR-CT and DentaScan MPR-CT images did not show significant difference in visibility of the mandibular canal. The study results shoe that Vimplant and DentaScan MPR-CT imaging systems offer significantly better images of the mandibular canal than conventional panoramic radiograph.

  13. Industrial radiography on radiographic paper

    International Nuclear Information System (INIS)

    Domanus, J.C.

    1977-11-01

    An investigation was performed to compare the quality of radiographic paper with that of X-ray film, after a review had been made of the rather scarce literature on the subject. The equipment used throughout the investigation is described, and characteristic curves for Agfa-Gevaert and Kodak papers exposed with different intensifying screens in the low and intermediate voltage range are reproduced. The relative speed, contrast and exposure latitude were computed from these curves. The quality of the radiographic image was checked on U/Al blocks and plates, Al and Fe blocks, and fiber-reinforced composites. Exposure charts for Al and Fe were made for various paper and screen combinations. Both the sharpness of the radiographic image as well as the influence of processing on speed and contrast were checked. Examples are given of the practical application of the paper for radiography of castings, weldings, solderings, assemblies, etc. (author)

  14. Efficacy study of the digital image processing with varying pixel size at A/D conversion of the chest radiograph

    Energy Technology Data Exchange (ETDEWEB)

    Inamoto, Kazuo; Tanaka, Shinichi; Miura, Takashi; Takahashi, Akira; Iwata, Tetsuya

    1984-12-01

    In the study for development of medical image archiving system, we made experiments in the field of conversion of a X-ray picture to a digital form. Three sets of chest radiograph were selected for the study of digitalization by reading different pixel size (150-300 m) in the method of A/D conversion using a drum scanner and again reconstructed to an analog form after D/A conversion. These copy films of different pixel size were shown and evaluated by 48 volunteer doctors to choose a favorite picture. It did not always follow that the most favorite picture was the finest one using the smallest pixel size. This discrepancy was further analyzed by measurement of a density histogram. By comparison studies of density curves in the same ROI of different pixel size pictures, it was concluded that their choices were dependent on not only fineness but also contrast of an output image after D/A conversion. Often better contrast picture was a key to the selection more than the pixel size. This indicates that digital storing radiographs will be possibly regenerated to the real image by the skillful operation of pixel size and contrast of a radiograph. The results will contribute to the process of recording analog X-ray picture by a digital form in the medical image archiving system.

  15. Commitment of the radiographer - does it matter to the patient?

    International Nuclear Information System (INIS)

    Blagoeva, D.; Shuleva, L.; Goudeva, V.; Stoinova, V.

    2015-01-01

    Full text: Radiographers are responsible for providing safe and accurate imaging examinations in a wide range of clinical environments, using a variety of imaging modalities and techniques so that appropriate management and treatment of patients and clients can proceed. The purpose of this presentation is to discuss: the responsibilities of radiographer in the clinical radiology department; their professional judgment to decide how to achieve a diagnostic outcome; the relationship patient/radiographer; the impact of the radiographer on patient care. Patient care and advocacy has always been an integral part of the radiography profession. The radiographer should respect the patient at all the times, be genuine in nature and empathies with the patient‘s condition. Good listening and observational skills are also very important components. The radiographers are personally accountable for their work and professional conduct

  16. SU-E-I-91: Development of a Compact Radiographic Simulator Using Microsoft Kinect.

    Science.gov (United States)

    Ono, M; Kozono, K; Aoki, M; Mizoguchi, A; Kamikawa, Y; Umezu, Y; Arimura, H; Toyofuku, F

    2012-06-01

    Radiographic simulator system is useful for learning radiographic techniques and confirmation of positioning before x-ray irradiation. Conventional x-ray simulators have drawbacks in cost and size, and are only applicable to situations in which position of the object does not change. Therefore, we have developed a new radiographic simulator system using an infrared-ray based three-dimensional shape measurement device (Microsoft Kinect). We made a computer program using OpenCV and OpenNI for processing of depth image data obtained from Kinect, and calculated the exact distance from Kinect to the object by calibration. Theobject was measured from various directions, and positional relationship between the x-ray tube and the object was obtained. X-ray projection images were calculated by projecting x-rays onto the mathematical three-dimensional CT data of a head phantom with almost the same size. The object was rotated from 0 degree (standard position) through 90 degrees in increments of 10 degrees, and the accuracy of the measured rotation angle values was evaluated. In order to improve the computational time, the projection image size was changed (512*512, 256*256, and 128*128). The x-ray simulation images corresponding to the radiographic images produced by using the x-ray tube were obtained. The three-dimensional position of the object was measured with good precision from 0 to 50 degrees, but above 50 degrees, measured position error increased with the increase of the rotation angle. The computational time and image size were 30, 12, and 7 seconds for 512*512, 256*256, and 128*128, respectively. We could measure the three-dimensional position of the object using properly calibrated Kinect sensor, and obtained projection images at relatively high-speed using the three-dimensional CTdata. It was suggested that this system can be used for obtaining simulated projection x-ray images before x-ray exposure by attaching this device onto an x-ray tube. © 2012 American

  17. Novel Card Games for Learning Radiographic Image Quality and Urologic Imaging in Veterinary Medicine.

    Science.gov (United States)

    Ober, Christopher P

    Second-year veterinary students are often challenged by concepts in veterinary radiology, including the fundamentals of image quality and generation of differential lists. Four card games were developed to provide veterinary students with a supplemental means of learning about radiographic image quality and differential diagnoses in urogenital imaging. Students played these games and completed assessments of their subject knowledge before and after playing. The hypothesis was that playing each game would improve students' understanding of the topic area. For each game, students who played the game performed better on the post-test than students who did not play that game (all pgames, students who played each respective game demonstrated significant improvement in scores between the pre-test and the post-test (pgames were both helpful and enjoyable. Educationally focused games can help students learn classroom and laboratory material. However, game design is important, as the game using the most passive learning process also demonstrated the weakest results. In addition, based on participants' comments, the games were very useful in improving student engagement in the learning process. Thus, use of games in the classroom and laboratory setting seems to benefit the learning process.

  18. The use and abuse of radiographic grids

    International Nuclear Information System (INIS)

    Brough, P.D.

    1981-01-01

    It is generally accepted that scattered radiation degrades the quality of the radiographic image. When this problem occurs, a radiographic grid may be applied which necessitates an increase in exposure. Investigations are reported in the following areas: reasons for the introduction of a radiographic grid; the ratio between kilovoltage and grid ratio; techniques resulting in higher contrast and resolution at low patient dose and the abuse of grids

  19. Coronal and Intraradicular Appearances Affect Radiographic Perception of the Periapical Region.

    Science.gov (United States)

    Strong, Julie W; Woodmansey, Karl F; Khademi, John A; Hatton, John F

    2017-05-01

    The influence of the radiographic appearances of the coronal and intraradicular areas on periapical radiographic interpretation has been minimally evaluated in dentistry and endodontics. The purpose of this study was to evaluate the effects that the coronal and intraradicular radiographic appearance has on endodontists' radiographic interpretations of periapical areas. In a split-group study design using an online survey format, 2 pairs of digital periapical radiographic images were evaluated by 2 groups (A and B) of endodontist readers for the presence of a periapical finding. The images in each pair were identical except that 1 image of each image pairs had coronal restorations and/or root canal fillings altered using Adobe Photoshop software (Adobe Systems, San Jose, CA). The periapical areas were not altered. Using a 5-point Likert scale, the endodontist readers were asked to "Please evaluate the periapical area(s)." A Mann-Whitney U test was used to statistically evaluate the difference between the groups. Significance was set at P < .01. There were 417 readers in group A and 442 readers in group B. The Mann-Whitney U test showed a significant difference in the responses between the groups for both image pairs (P < .01). Because the periapical areas of the image pairs were unaltered, the differing coronal and intraradicular areas of the radiographs appear to have influenced endodontists' interpretations of the periapical areas. This finding has implications for all radiographic outcome assessments. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  20. Feature Extraction of Weld Defectology in Digital Image of Radiographic Film Using Geometric Invariant Moment and Statistical Texture

    International Nuclear Information System (INIS)

    Muhtadan

    2009-01-01

    The purpose of this research is to perform feature extraction in weld defect of digital image of radiographic film using geometric invariant moment and statistical texture method. Feature extraction values can be use as values that used to classify and pattern recognition on interpretation of weld defect in digital image of radiographic film by computer automatically. Weld defectology type that used in this research are longitudinal crack, transversal crack, distributed porosity, clustered porosity, wormhole, and no defect. Research methodology on this research are program development to read digital image, then performing image cropping to localize weld position, and then applying geometric invariant moment and statistical texture formulas to find feature values. The result of this research are feature extraction values that have tested with RST (rotation, scale, transformation) treatment and yield moment values that more invariant there are ϕ 3 , ϕ 4 , ϕ 5 from geometric invariant moment method. Feature values from statistical texture that are average intensity, average contrast, smoothness, 3 rd moment, uniformity, and entropy, they used as feature extraction values. (author)

  1. A self-directed learning intervention for radiographers rating mammographic breast density

    International Nuclear Information System (INIS)

    Ekpo, E.U.; Hogg, P.; Wasike, E.; McEntee, M.F.

    2017-01-01

    Purpose: Subjective methods of mammographic breast density (MBD) assessment are prone to inter-reader variability. This work aims to assess the impact of a short self-directed, experiential learning intervention on radiographers' reproducibility of MBD assessment. Method: The study used two sets of images (test and learning intervention) containing left craniocaudal and left mediolateral oblique views. The test set had MBD ratings from Volpara™ and radiologists using the fourth edition Breast Imaging and Data Systems (BI-RADS ® ). Seven radiographers rated the MBD of the test set before and after a self-directed learning intervention using the percentage descriptors in the fourth edition BI-RADS ® Atlas. The inter-reader agreement, the agreement between radiographers and Volpara™ as well as radiologists, was assessed using a Weighted Kappa (κ w ). Results: Overall, radiographers' inter-reader agreement (κ w ) was substantial (0.79; 95% CI: 0.70–0.87) before the intervention and almost perfect (0.84; 95% CI: 0.77–0.90) after the intervention. Before the intervention, radiographers demonstrated fair agreement with radiologists (0.24; 95% CI: −0.46–0.61) and Volpara™ (0.24; 95% CI: −0.41–0.59). A fair but slightly improved agreement was also observed between radiographers and radiologists (0.31; 95% CI: −0.33–0.64) as well as Volpara™ (0.28; 95% CI: −0.34–0.61) after the intervention. Conclusion: Findings demonstrate that a short duration self-directed, experiential learning intervention reduces inter-reader differences in MBD classification, but has a negligible impact on improving the agreement between inexperienced and expert readers. - Highlights: • Radiographers' MBD rating show fair agreement with radiologists and Volpara™. • Experiential learning intervention improved reproducibility of MBD classification. • Enhanced MBD rating training may be required to develop a standard fit for practice.

  2. Radiographic imaging of otitis media and interna in pigs

    International Nuclear Information System (INIS)

    Harlizius, J.; Kluczniok, C.; Bollwahn, W.

    1997-01-01

    Middle and inner ear infections have been reported as a clinical entity in swine, other animal species and humans. In pigs, the anatomical-pathological and microbiological findings have been described. In this report, we describe radiographic findings in affected pigs. A total of 25 pigs with a head tilt and circling, as clinical signs of otitis media and interna, were examined. The majority were weaner-pigs with dyspnea or rhinitis. In radiographs, there was an increased opacity of the bulla tympanica, often accompanied by marginal destruction or thickening of the bulla wall. The radiographic findings confirmed the clinical diagnosis in each affected pig, but there were 5 false positive interpretations

  3. Radiographic evaluation of coxofemoral joint laxity in dogs part I: New stress-radiographic positioning techniques

    International Nuclear Information System (INIS)

    Phiwipha Kamonrat; Duangdaun Kaenkangploo

    2002-01-01

    Two new stress-radiographic positioning techniques, namely 60 deg and 90 deg stress techniques, were introduced for quantifying hip joint laxity in dogs. The comparative characteristics and efficiency of these new techniques with angled hindlimbs were evaluated relative to the standard hip-extended radiographic technique. Forty, healthy, mongrel dogs with normal hip joint conformation were anesthetized and placed in dorsal recumbency before 3 radiograhps of the standard, 60 deg , and 90 deg stress techniques were taken. For the 60 deg stress technique, hindlimbs were extended in parallel to each other at 60 deg angled to the table top and stifles were slightly rotated inward, femoral heads were manually pushed in a craniodorsal direction during exposure. For the 90 deg stress technique, femurs were positioned perpendicular to the table top, stifles were 90 deg flexed and adducted and femoral heads were manually pushed in a craniodorsal direction during exposure. The subluxation index (SI) and dorsolateral subluxation score (DLS score) were calculated from 3 radiographic views for both hip joints to quantitate the relative degree of joint laxity. Results of the study indicated that the 60 deg (SI = 0.20+-0.045, DLS score = 62.5+-7.96 percent) and 90 deg (SI = 0.23+-0.044, DLS score = 61.2+-9.47 percent) stress-radiographs yielded significantly (p0.001) higher degree of hip joint laxity than the standard technique (SI)

  4. Interpretation and digestion of radiograph

    International Nuclear Information System (INIS)

    Abdul Nassir Ibrahim; Azali Muhammad; Ab. Razak Hamzah; Abd. Aziz Mohamed; Mohamad Pauzi Ismail

    2008-01-01

    Radiography digestion is final test for the radiography to make sure that radiograph produced will inspect their quality of the image before its interpreted. This level is critical level where if there is a mistake, all of the radiography work done before will be unaccepted. So as mention earlier, it can waste time, cost and more worst it can make the production must shut down. So, this step, level two radiographers or interpreter must evaluate the radiograph carefully. For this purpose, digestion room and densitometer must used. Of course all the procedure must follow the specification that mentioned in document. There are several needs must fill before we can say the radiograph is corrected or not like the location of penetrameter, number of penetrameter that showed, the degree of density of film, and usually there is no problem in this step and the radiograph can go to interpretation and evaluation step as will mentioned in next chapter.

  5. Elements and process for recording direct image neutron radiographs

    International Nuclear Information System (INIS)

    Poignant, R.V. Jr.; Przybylowicz, E.P.

    1975-01-01

    An element is provided for recording a direct image neutron radiograph, thus eliminating the need for a transfer step (i.e., the use of a transfer screen). The element is capable of holding an electrostatic charge and comprises a first layer for absorbing neutrons and generating a current by dissipation of said electrostatic charge in proportion to the number of neutrons absorbed, and a second layer for conducting the current generated by the absorbed neutrons, said neutron absorbing layer comprising an insulative layer comprising neutron absorbing agents in a concentration of at least 10 17 atoms per cm 3 . An element for enhancing the effect of the neutron beam by utilizing the secondary emanations of neutron absorbing materials is also disclosed along with a process for using the device. (U.S.)

  6. The cervical spine in rheumatoid arthritis: relationship between neurologic signs and morphology on MR imaging and radiographs

    Energy Technology Data Exchange (ETDEWEB)

    Reijnierse, M. [Dept. of Diagnostic Radiology and Nuclear Medicine, Leiden (Netherlands); Bloem, J.L. [Dept. of Diagnostic Radiology and Nuclear Medicine, Leiden (Netherlands); Kroon, H.M. [Dept. of Diagnostic Radiology and Nuclear Medicine, Leiden (Netherlands); Holscher, H.C. [Dept. of Diagnostic Radiology and Nuclear Medicine, Leiden (Netherlands); Dijkmans, B.A.C. [Dept. of Rheumatology, Univ. Hospital Leiden (Netherlands); Breedveld, F.C. [Dept. of Rheumatology, Univ. Hospital Leiden (Netherlands); Hansen, B. [Dept. of Medical Statistics, Univ. Hospital Leiden (Netherlands)

    1996-02-01

    Sixty-three consecutive patients with RA and subjective symptoms, especially neck or occipital pain, and/or clinical objective signs consistent with a compromised cervical cord were included in this study. The patients were prospectively assigned to one of three classes on the basis of their neurologic status. Lateral cervical spine radiographs and sagittal Tl-weighted and gradient echo images were performed. The qualitative MR features evaluated were erosion of the dens and atlas, brain stem compression, subarachnoid space encroachment, pannus around the dens, appearance of the fat body caudal to the clivus, and the signal intensity of the pannus. The quantitative imaging parameters were the cervicomedullary angle and the distance of the dens to the line of McRae. Damage documented with radiographs and MR imaging in patients with RA is often severe, even in those without neurologic signs (class 1). None of the abnormalities confined to the atlantoaxial level correlated significantly with neurologic classification. Subarachnoid space encroachment anywhere in the entire cervical spine did correlate significantly with neurologic classification. (orig./MG)

  7. The cervical spine in rheumatoid arthritis: relationship between neurologic signs and morphology on MR imaging and radiographs

    International Nuclear Information System (INIS)

    Reijnierse, M.; Bloem, J.L.; Kroon, H.M.; Holscher, H.C.; Dijkmans, B.A.C.; Breedveld, F.C.; Hansen, B.

    1996-01-01

    Sixty-three consecutive patients with RA and subjective symptoms, especially neck or occipital pain, and/or clinical objective signs consistent with a compromised cervical cord were included in this study. The patients were prospectively assigned to one of three classes on the basis of their neurologic status. Lateral cervical spine radiographs and sagittal Tl-weighted and gradient echo images were performed. The qualitative MR features evaluated were erosion of the dens and atlas, brain stem compression, subarachnoid space encroachment, pannus around the dens, appearance of the fat body caudal to the clivus, and the signal intensity of the pannus. The quantitative imaging parameters were the cervicomedullary angle and the distance of the dens to the line of McRae. Damage documented with radiographs and MR imaging in patients with RA is often severe, even in those without neurologic signs (class 1). None of the abnormalities confined to the atlantoaxial level correlated significantly with neurologic classification. Subarachnoid space encroachment anywhere in the entire cervical spine did correlate significantly with neurologic classification. (orig./MG)

  8. Radiographic element

    International Nuclear Information System (INIS)

    Abbott, T.I.; Jones, C.G.

    1984-01-01

    Radiographic elements are disclosed comprised of first and second silver halide emulsion layers separated by an interposed support capable of transmitting radiation to which the second image portion is responsive. At least the first imaging portion contains a silver halide emulsion in which thin tubular silver halide grains of intermediate aspect ratios (from 5:1 to 8:1) are present. Spectral sensitizing dye is adsorbed to the surface of the tubular grains. Increased photographic speeds can be realized at comparable levels of crossover. (author)

  9. Inadequate pelvic radiographs: implications of not getting it right the first time.

    Science.gov (United States)

    Parker, S; Nagra, N S; Kulkarni, K; Pegrum, J; Barry, S; Hughes, R; Ghani, Y

    2017-09-01

    Introduction Pelvic radiography is a frequent investigation. European guidelines aim to ensure appropriate use and adequate quality. When initial images are inadequate, repeat radiographs are often required, which may have significant patient safety and economic implications. Objectives The study aimed to assess the adequacy of pelvic imaging across three orthopaedic centres, to identify causes for inadequate imaging and to establish the cost of inadequate imaging from financial and patient safety perspectives. Methods Pelvic radiographs were identified on Picture Archiving and Communication System software at three UK hospitals. Radiographs were assessed against European guidelines and indications for repeat imaging were analysed. Results A total of 1,531 sequential pelvic radiographs were reviewed. The mean age of patients was 60 years (range 5 months to 101 years). Of this total, 51.9% of images were suboptimal, with no significant difference across the three hospitals (P > 0.05). Hospital 3 repeated radiographs in 6.3% of cases, compare with 18.1% and 19.7% at hospitals 1 and 2, respectively (P > 0.05). Hospital 3 identified pathology missed on the initial radiograph in 1% of cases, compared with 5.4% and 5.5% at hospitals 1 and 2, respectively (P > 0.05). Out-of-hours imaging is associated with a higher rate of suboptimal quality (69.1%) compared with normal working hours (51.3%; P = 0.006). Adequacy rates vary with age (χ 2 = 43.62, P hours imaging.

  10. Digital radiographic techniques in the analysis of paintings

    International Nuclear Information System (INIS)

    James, A.E. Jr.; Gibbs, S.J.; James, A.E. III; Pickens, D.R.; Sloan, M.; Price, R.R.; Erickson, J.J.

    1985-01-01

    In this chapter the authors use the term digital radiography to mean any method of radiographic image production in which the silver halide-based film is replaced by an electronic sensor for production of an image. There are essentially three types of digital radiographic systems available at present, but others will be developed. These differ primarily in the method of image production and the rapidity with which images can be produced. The three methods discussed are digital fluoroscopy, scanned projection radiography, and the scanned point source radiography. Each has certain characteristics which, if properly utilized, will allow improved x-ray analysis of paintings

  11. Computed tomography for radiographers

    International Nuclear Information System (INIS)

    Brooker, M.J.

    1986-01-01

    This book is directed towards giving radiographers an introduction to and basic knowledge of computerized tomography. The technical section discusses gantries and x-ray production, computer and disc drive image display, storage, artefacts quality assurance and design of departments. The clinical section includes patient preparation, radiotherapy planning, and interpretation of images from various areas of the anatomy. (U.K.)

  12. Evaluation of the improvement of the double-contrast radiographic image quality in the prone position brought about by the use of a decision tree in the screening examination

    International Nuclear Information System (INIS)

    Yamada, Yasuji; Nakamura, Syunichi; Ohno, Ryuichi; Azuma, Hiroshi; Fujinaga, Akira; Nagai, Makoto

    2009-01-01

    We designed a decision tree in order to improve the double-contrast radiographic image quality in the prone position and compensate for the disparity of technique among radiological technologists. We evaluated 391 consecutive individuals who underwent medical checkups at our hospital. Three decision trees, id est (i.e.), Tree 1, Tree 2 and Tree 3, were constructed based on the axis and contortion of the stomach with the use of a prone filling image, and then the insertion site of compression pillow was altered. The image quality at the gastric angulus, the gastric body and the antrum was evaluated based on our original numeric scale, and was compared between the previous method and the present method which employs a decision tree. The image quality improved more significantly in the present method employing a decision tree compared with the previous method, for each decision tree: from 90 points to 100 points for Tree 1, from 70 points to 95 points for Tree 2, and from 39.5 points for 85.7 points in Tree 3. These results indicate that our original procedure employing a decision tree improves the radiographic image quality in the prone position and compensates for the disparity of technique among radiological technologists. Therefore, the present method may be expected to serve as the standard procedure of double-contrast radiography in the prone position. (author)

  13. Matching hand radiographs

    NARCIS (Netherlands)

    Kauffman, J.A.; Slump, Cornelis H.; Bernelot Moens, H.J.

    2005-01-01

    Biometric verification and identification methods of medical images can be used to find possible inconsistencies in patient records. Such methods may also be useful for forensic research. In this work we present a method for identifying patients by their hand radiographs. We use active appearance

  14. Optimization of Dose and Image Quality in Full-fiand Computed Radiography Systems for Common Digital Radiographic Examinations

    Directory of Open Access Journals (Sweden)

    Soo-Foon Moey

    2018-01-01

    Full Text Available IntroductionA fine balance of image quality and radiation dose can be achieved by optimization to minimize stochastic and deterministic effects. This study aimed in ensuring that images of acceptable quality for common radiographic examinations in digital imaging were produced without causing harmful effects. Materials and MethodsThe study was conducted in three phases. The pre-optimization involved ninety physically abled patients aged between 20 to 60 years and weighed between 60 and 80 kilograms for four common digital radiographic examinations. Kerma X_plus, DAP meter was utilized to measure the entrance surface dose (ESD while effective dose (ED was estimated using CALDose_X 5.0 Monte Carlo software. The second phase, an experimental study utilized an anthropomorphic phantom (PBU-50 and Leeds test object TOR CDR for relative comparison of image quality. For the optimization phase, the imaging parameters with acceptable image quality and lowest ESD from the experimental study was related to patient’s body thickness. Image quality were evaluated by two radiologists using the modified evaluation criteria score lists. ResultsSignificant differences were found for image quality for all examinations. However significant difference for ESD were found for PA chest and AP abdomen only. The ESD for three of the examinations were lower than all published data. Additionally, the ESD and ED obtained for all examinations were lower than that recommended by radiation regulatory bodies. ConclusionOptimization of image quality and dose was achieved by utilizing an appropriate tube potential, calibrated automatic exposure control and additional filtration of 0.2mm copper.

  15. Assessment of hindfoot alignment using MRI and standing hindfoot alignment radiographs (Saltzman view)

    Energy Technology Data Exchange (ETDEWEB)

    Bueber, Nydia; Zanetti, Marco [Clinic Hirslanden, Department of Musculoskeletal Radiology, Zurich (Switzerland); Frigg, Arno [Clinic Hirslanden, Centre for Foot and Ankle Surgery, Zurich (Switzerland); Saupe, Nadja [Clinic Hirslanden, Department of Musculoskeletal Radiology, Zurich (Switzerland); Clinic Hirslanden Zurich, Department of Musculoskeletal Radiology, Zurich (Switzerland)

    2018-01-15

    To compare the hindfoot alignment measured on standing HAV radiographs (Saltzman view) and on non-weight-bearing coronal MR images. The apparent moment arm was measured on weight-bearing conventional radiographs (Saltzman views) and on MRIs of the ankle in 50 consecutive patients (mean age, 54 years; age range, 18-77 years). The evaluation was performed independently by three readers using analogous reference points for both methods. Positive values were assigned when the deepest point of the calcaneus was lateral to the tibial axis as valgus, negative values as varus. The intertechnique agreement and correlation for the measurements performed with HAV radiographs and MRI were assessed for each reader using the Bland-Altman method and the Pearson correlation coefficient, respectively. The interobserver agreement was assessed using the intraclass correlation coefficient. The means of apparent moment arms, with the standard deviation (SD) in parentheses, of three readers were +2.0 (±8.4) mm, +1.5 (±6.6) mm and -1.4 (±8.2) mm on HAV radiographs and +4.6 (±7.4) mm, +6.3 (±5.3) mm and +5.4 (±6.4) mm on MRI. The Bland-Altman analysis found a systematic bias for all three readers, corresponding to an overestimation of measurements with MRI (systematic bias ranging from 2.6 to 4.8 mm). The intertechnique correlation was found moderate to high. The Pearson coefficients for the three readers were 0.75, 0.64 and 0.65. The interobserver agreement among the three readers was 0.72, 0.77 and 0.68 for HAV, MRI and both modalities together, respectively. Hindfoot alignment can be estimated on MRI but the correlation between the values on HAV radiographs and MR images is only moderate with a tendency to increased positive values (valgization) on MR images. (orig.)

  16. Prototype system for enhancement of frontal chest radiographs using eigenimage processing

    International Nuclear Information System (INIS)

    Butler, A.; Bones, P.; Hurrell, M.

    2008-01-01

    A prototype system is described for enhancement of radiographic images in the eigen domain. The images chosen to enhance are frontal chest radiographs. This class of images has been chosen because it is both a clinically important examination and an example of the high-resolution images used within radiology. The enhancement method is based on principal components analysis, a multivariate statistical technique first used within image processing for face recognition. The method requires a training set of normal images to identify normal patterns of variance. The enhancement process then removes these normal patterns of variance, often increasing the relative intensity of pathologies. Enhanced images presented in this paper include a range of common pathologies found on chest radiographs. Details of implementation, computing expense and possible applications within radiology are discussed.

  17. Complete resolution and remodeling of chronic recurrent multifocal osteomyelitis on MRI and radiographs

    Energy Technology Data Exchange (ETDEWEB)

    Berkowitz, Y.J.; Greenwood, S.J.; Cassar-Pullicino, V.N. [Robert Jones and Agnes Hunt Orthopaedic Hospital NHS Foundation Trust, Department of Diagnostic Imaging, Oswestry, Shropshire (United Kingdom); Cribb, G. [Robert Jones and Agnes Hunt Orthopaedic Hospital NHS Foundation Trust, Department of Orthopaedic Oncology, Oswestry, Shropshire (United Kingdom); Davies, K. [Robert Jones and Agnes Hunt Orthopaedic Hospital NHS Foundation Trust, Department of Medicine, Oswestry, Shropshire (United Kingdom)

    2018-04-15

    Chronic recurrent multifocal osteomyelitis (CRMO) is a rare condition thought to be under-diagnosed, with a true prevalence of more than the 1 in 10,000 estimated. It is a condition that is classically described as polyostotic with a relapsing and remitting course, preferentially affecting the metaphyses of tubular bones in the pediatric population. Lesions have characteristic appearances of cortical hyperostosis and mixed lytic/sclerotic medullary appearances radiographically, with active osteitis and periostitis best seen with fluid-sensitive sequences on magnetic resonance imaging (MRI). There are reports of lesions resolving on follow-up radiographs and MRI scans, but no supporting images. In particular, although the marrow appearances and degree of osteitis have been shown to improve on MRI, complete resolution and remodeling back to normal has never been demonstrated. We present a case of a lesion that has completely healed and remodeled back to normal appearances on both radiographs and MRI, and consider this the standard for the often loosely used terms ''normalization'' and ''resolution''. We discuss the implications of this for our understanding of the natural history of CRMO, and how this adds weight to the condition being significantly under-diagnosed. It provides a ''gold standard'' to be aimed for when assessing treatments for CRMO, and the optimal outcomes that are possible. It also provides further insight into the potential of pediatric bone to recover and remodel when affected by inflammatory conditions. (orig.)

  18. Study on application of contrastmeter in radiographic examination, 1

    International Nuclear Information System (INIS)

    Ooka, Kiichi; Hirayama, Kazuo; Senda, Tomio.

    1986-01-01

    As a check on the image quality of radiograph, it is customary to place a Image Quality Indicator, I. Q. I., and a contrastmeter. Although the observation results of I. Q. I. on the radiograph are affected remarkably by the difference amonge individuals, the density difference of contrastmeter dose not depend on it since the radiographic density is measured with densitometer. In order to apply both I. Q. I. and contrastmeter on all material thickness, it is necessary to know the quantitative relationship between the I. Q. I. sensitivity and the density difference in the contrastmeter. The quantitative relationship for aluminium welds are discussed. The value of dennity difference when the I. Q. I. sensitivity is considered is suitable for controlling the image quality of radiograph. For the reason that the value of density difference of contrastmeter is not strongly infuluenced, it is necessary for adopting the value obtained by dividing the density difference by radiographic density. The dimension of contrastmeter for Aluminium welds more over 20 mm in material thickness should be 20 mm in width and 3.0 mm and 4.0 mm in thickness corresponding to the material thickness. (author)

  19. Neurologic dysfunction in patients with rheumatoid arthritis of the cervical spine. Predictive value of clinical, radiographic and MR imaging parameters

    Energy Technology Data Exchange (ETDEWEB)

    Reijnierse, M.; Kroon, H.M.; Holscher, H.C.; Bloem, J.L. [Dept. of Radiology, University Hospital Leiden (Netherlands); Dijkmans, B.A.C.; Breedveld, F.C. [Dept. of Rheumatology, University Hospital Leiden (Netherlands); Hansen, B. [Dept. of Medical Statistics, University Hospital Leiden (Netherlands); Pope, T.L. [Dept. of Diagnostic Radiology, Univ. of South Carolina (United States)

    2001-03-01

    The aim of this study was to evaluate if subjective symptoms, radiographic and especially MR parameters of cervical spine involvement, can predict neurologic dysfunction in patients with severe rheumatoid arthritis (RA). Sequential radiographs, MR imaging, and neurologic examination were performed yearly in 46 consecutive RA patients with symptoms indicative of cervical spine involvement. Radiographic parameters were erosions of the dens or intervertebral joints, disc-space narrowing, horizontal and vertical atlantoaxial subluxation, subluxations below C2, and the diameter of the spinal canal. The MR features evaluated were presence of dens and atlas erosion, brainstem compression, subarachnoid space encroachment, pannus around the dens, abnormal fat body caudal to the clivus, cervicomedullary angle, and distance of the dens to the line of McRae. Muscle weakness was associated with a tenfold increased risk of neurologic dysfunction. Radiographic parameters were not associated. On MR images atlas erosion and a decreased distance of the dens to the line of McRae showed a fivefold increased risk of neurologic dysfunction. Subarachnoid space encroachment was associated with a 12-fold increased risk. Rheumatoid arthritis patients with muscle weakness and subarachnoid space encroachment of the entire cervical spine have a highly increased risk of developing neurologic dysfunction. (orig.)

  20. Neurologic dysfunction in patients with rheumatoid arthritis of the cervical spine. Predictive value of clinical, radiographic and MR imaging parameters

    International Nuclear Information System (INIS)

    Reijnierse, M.; Kroon, H.M.; Holscher, H.C.; Bloem, J.L.; Dijkmans, B.A.C.; Breedveld, F.C.; Hansen, B.; Pope, T.L.

    2001-01-01

    The aim of this study was to evaluate if subjective symptoms, radiographic and especially MR parameters of cervical spine involvement, can predict neurologic dysfunction in patients with severe rheumatoid arthritis (RA). Sequential radiographs, MR imaging, and neurologic examination were performed yearly in 46 consecutive RA patients with symptoms indicative of cervical spine involvement. Radiographic parameters were erosions of the dens or intervertebral joints, disc-space narrowing, horizontal and vertical atlantoaxial subluxation, subluxations below C2, and the diameter of the spinal canal. The MR features evaluated were presence of dens and atlas erosion, brainstem compression, subarachnoid space encroachment, pannus around the dens, abnormal fat body caudal to the clivus, cervicomedullary angle, and distance of the dens to the line of McRae. Muscle weakness was associated with a tenfold increased risk of neurologic dysfunction. Radiographic parameters were not associated. On MR images atlas erosion and a decreased distance of the dens to the line of McRae showed a fivefold increased risk of neurologic dysfunction. Subarachnoid space encroachment was associated with a 12-fold increased risk. Rheumatoid arthritis patients with muscle weakness and subarachnoid space encroachment of the entire cervical spine have a highly increased risk of developing neurologic dysfunction. (orig.)

  1. Evaluation of the radiopacities of four different root canal sealers by digital radiographic technique

    Directory of Open Access Journals (Sweden)

    Özgür Özdemir

    2016-05-01

    Full Text Available OBJECTIVE: The aim of this study was to compare the radiopacities of four different root canal sealers and gutta-percha. MATERIALS AND METHOD: AH Plus, iRootSP, MTA Fillapex and Sealapex as root canal sealers and gutta-percha cones were tested. Standardized discs of the root canal sealers and the gutta-percha were prepared. Digital radiographs of the discs and an aluminum penetrometer were obtained by using a phosphor plate. The radiographic density of the sealers and the gutta-percha were measured by using the digital radiographic system’s own measurement tool, and equivalent aluminum thicknesses were determined by using an image editing software. Differences among radiopacities of the root canal sealers and the gutta-percha were analyzed using One-way ANOVA and Tukey post-hoc tests. RESULTS: Aluminum thickness equivalents of the radiopacity values of the samples, in descending order, were: AH Plus, Sealapex, iRootSP, MTA Fillapex and gutta-percha. No significant difference was found between the radiopacity values of AH Plus and Sealapex (p>0.05. There were statistically significant differences between these two groups (AH Plus and Sealapex and all other experimental groups (p<0.05. CONCLUSION: AH Plus and Sealapex exhibited the highest radiopacity values among tested groups. In addition, all tested materials fulfilled the minimum standard value requirements suggested by International Standardization Organization and American National Standards Institute.

  2. Cervical spine trauma radiographs: Swimmers and supine obliques; an exploration of current practice

    Energy Technology Data Exchange (ETDEWEB)

    Fell, Michael, E-mail: michael.fell@mkgeneral.nhs.u [Milton Keynes General Hospital, Radiology Standing Way, Eaglestone, Milton Keynes, Buckinghamshire MK6 5LD (United Kingdom)

    2011-02-15

    The study objectives were: to investigate current cervical spine radiographic imaging practices in conscious adult patients with suspected neck injury; reasons behind variation and consideration of dose estimates were explored. Comparison with a previous survey has been made. Questionnaires were sent to superintendent radiographers responsible for accident and emergency X-ray departments in English trusts with over 8500 emergency admissions per year, with a response rate of 97% (n = 181/186). Departmental cervical spine imaging protocols were reported by 82% of respondents. None use fewer than the three standard projections; if the cervicothoracic junction (C7/T1), is not adequately demonstrated 87% use swimmers projections, 9% supine obliques, 3% CT alone. Following projectional radiography, 97% perform CT. A significant (p = 0.018) increase was found since 1999 in CT use once the swimmers projection fails; fewer now use obliques at this point, continuing with CT instead. No significant difference (p = 0.644) was found in choice of first supplementary radiographs; despite British Trauma Society's recommendation to undertake supine obliques, swimmers remain the most widespread technique. An 85% response rate (n = 103/121) completed a second questionnaire, exploring reasons behind the various practices. Several reported a perceived difficulty in interpreting oblique radiographs, some a concern over high dose of the swimmers. Numerous issues affect the acquisition of cervical spine radiographs. Patient radiation dose should be a major consideration in selection of technique. A potential need for training in interpretation of obliques is highlighted. Specific guidelines for optimum projections should be researched, and protocols issued to ensure best practice.

  3. Interpretation and evaluation of radiograph

    International Nuclear Information System (INIS)

    Abdul Nassir Ibrahim; Azali Muhammad; Ab. Razak Hamzah; Abd. Aziz Mohamed; Mohamad Pauzi Ismail

    2008-01-01

    After digestion, the interpreter must interpreted and evaluate the image on film, usually many radiograph stuck in this step, if there is good density, so there are no problem. This is a final stage of radiography work and this work must be done by level two or three radiographer. This is a final stages before the radiographer give a result to their customer for further action. The good interpreter must know what kind of artifact, is this artifact are dangerous or not and others. In this chapter, the entire artifact that usually showed will be discussed briefly with the good illustration and picture to make the reader understand and know the type of artifact that exists.

  4. X radiations dosimetry in pulmonary radiographs: study of a non standard room

    International Nuclear Information System (INIS)

    Bied, J.C.; Philippon, B.

    1998-01-01

    A radiograph room can present a default of radiation protection. But it is possible that the radiation protection is here only to mask a protection of an other type. For the case of a lungs type radiograph room, the monitoring does not reveal any problem of radiation protection. These results do not bring to the fore any high radiations doses. But they are an illustration of operators positions, and these ones should be better protected at the extremity of the room, that should allow a correct vision of lungs radiographs and a more important limitation of irradiation. (N.C.)

  5. Determination of bone mineral density of the distal extremity of the radio in Rottweiller, by radiographic optic densitometry;Determinacao da densidade mineral ossea da extremidade distal do radio de caes da raca Rottweiller, por meio da densitometria optica radiografica

    Energy Technology Data Exchange (ETDEWEB)

    Alves, Jefferson Douglas Soares, E-mail: radiologia@unifeob.edu.b [Fundacao de Ensino Octavio Bastos (UNIFEOB), Sao Joao da Boa Vista, SP (Brazil). Fac. de Medicina e Veterinaria; Sterman, Franklin de Almeida [Universidade de Sao Paulo (USP), Butanta, SP (Brazil). Fac. de Medicina Veterinaria e Zootecnia. Dept. de Cirurgia

    2010-06-15

    This study allowed the standardization of the bone mineral density (BMD) of the distal extremity of the radio of 36 dogs adults in Rottweiler breed by radiographic optic densitometry. The limbs of the animals were radiographed with scale of aluminum that served as a reference. The radiographs images were digitalized and analyzed by a computer program for comparison of gray tones between the standard image and the image of the reference scale radiographed with the bone. Afterwards the values of density were expressed in millimeters of aluminum. Also studied the correlations between BMD and the sex, weight and external measures as the length of spine, height of the animal and circumference the distal extremity of the limb in study. The mean values and standard deviations of the bone mineral density of the distal extremity of the radio were: for the metaphyseal region the average of BMD of 7,88+-0,89 mmAl, the diaphyseal region 1 the average of BMD of 8,58+-0,80 mmAl and for diaphyseal region 2 of BMD of 9,00+-0,74 mmAl. (author)

  6. Clinical image quality evaluation for panoramic radiography in Korean dental clinics

    International Nuclear Information System (INIS)

    Choi, Bo Ram; Choi, Da Hye; Huh, Kyung Hoe; Yi, Won Jin; Heo, Min Suk; Choi, Soon Chul; Bae, Kwang Hak; Lee, Sam Sun

    2012-01-01

    The purpose of this study was to investigate the level of clinical image quality of panoramic radiographs and to analyze the parameters that influence the overall image quality. Korean dental clinics were asked to provide three randomly selected panoramic radiographs. An oral and maxillofacial radiology specialist evaluated those images using our self-developed Clinical Image Quality Evaluation Chart. Three evaluators classified the overall image quality of the panoramic radiographs and evaluated the causes of imaging errors. A total of 297 panoramic radiographs were collected from 99 dental hospitals and clinics. The mean of the scores according to the Clinical Image Quality Evaluation Chart was 79.9. In the classification of the overall image quality, 17 images were deemed 'optimal for obtaining diagnostic information,' 153 were 'adequate for diagnosis,' 109 were 'poor but diagnosable,' and nine were 'unrecognizable and too poor for diagnosis'. The results of the analysis of the causes of the errors in all the images are as follows: 139 errors in the positioning, 135 in the processing, 50 from the radiographic unit, and 13 due to anatomic abnormality. Panoramic radiographs taken at local dental clinics generally have a normal or higher-level image quality. Principal factors affecting image quality were positioning of the patient and image density, sharpness, and contrast. Therefore, when images are taken, the patient position should be adjusted with great care. Also, standardizing objective criteria of image density, sharpness, and contrast is required to evaluate image quality effectively.

  7. Non-destructive assay employing 2D and 3D digital radiographic imaging acquired with thermal neutrons and reactor-produced radioisotopes

    International Nuclear Information System (INIS)

    Silvani, Maria Ines; Almeida, Gevaldo Lisboa de; Lopes, Ricardo T.

    2011-01-01

    The inner structure of some objects can only be visualized by using suitable techniques, when safety reasons or expensive costs preclude the application of invasive procedures. The kind of agent rendering an object partially transparent, unveiling thus its features, depends upon the object size and composition. As a rough rule of thumb, light materials are transparent to gamma and X-rays while the heavy ones are transparent to neutrons. When, after traversing an object, they hit a proper 2-D detector, a radiograph is produced representing a convoluted cross section, called projection, of that object. Taking a large number of such projections for different object attitudes, it is possible to obtain a 3-D tomography of the object as a map of attenuation coefficients. This procedure however, besides a time-consuming task, requires specially tailored equipment and software, not always available or affordable. Yet, in some circumstances it is feasible to replace the 3-D tomography by a stereoscopy, allowing one to visualize the spatial configuration of the object under analysis. In this work, 2-D and 3-D radiographic images have been acquired using thermal neutrons and reactor-produced radioisotopes and proper imaging plates as detectors. The stereographic vision has been achieved by taking two radiographs of the same object at different angles, from the detector point of view. After a treatment to render them red-white and green-white they were properly merged to yield a single image capable to be watched with red-green glasses. All the image treatment and rendering has been performed with the software ImageJ. (author)

  8. Development of tools for radiographic defects scanning in ceramic materials

    International Nuclear Information System (INIS)

    Lipnik, Boris.

    1994-03-01

    This work is concentrated on implementation of the most used non-destructive technique - radiography to quality control of structural ceramics. The present thesis deals with microfocus radiographic evaluation of ceramics produced by slip casting method. Radiographic processes are examined relying on image processing by algorithms expanded from others developed for tomographic images of non ceramics objects. At the first stage experiments aimed for characterization of a real-time microfocus radiographic system were carried out. The question of signal-to-noise ratio referring to a defect's detection limit was explored. Arithmetic image operations were used to correct for the background variations. At the second stage microfocus radiographs of: ceramics were systematically processed and analyzed by means of regularization and 'weak membrane' algorithms. The images were considerably improved and it resulted in identification and dimension extraction of defects as small as 40 pico meter . The usefulness of pseudocoloring methods was explored to obtain a fast assessment of gray level variations and to detect more details in the initial digital image. The potential for practical application was found to be very reasonable. The problems experienced were discussed along with suggestions for further studies and improvement

  9. Observations of radiographer communication: An exploratory study using Transactional Analysis

    International Nuclear Information System (INIS)

    Booth, Lisa A.; Manning, David J.

    2006-01-01

    Purpose: Communication in medical imaging is a neglected area of research, despite the necessity for good communication if optimum diagnostic images are to be achieved. Methods: The present study has investigated the styles of communication used in medical imaging, using an approach known as Transactional Analysis. This approach has been demonstrated previously as having reliability and validity, using observations and supporting interviews with medical imaging staff, along with inter-rater observations of radiographer-patient interactions. Results: The results indicate that Transactional Analysis can be used effectively for identifying and naming interaction events in diagnostic radiography, with diagnostic radiographers using five styles of communication. Conclusion: Radiographers tend to use Parental styles of communicating; these styles are commonly associated with a practitioner-centred approach to dealing with patients which often result in non-adherence

  10. Radiographic Control of 137-Cs Brachytherapy Sources

    International Nuclear Information System (INIS)

    Bistrovic, M.; Viculin, T.; Jurkovic, S.

    2003-01-01

    1 37C s brachytherapy sources are practical for the intracavitary application due to their relatively long lifetime (T 1/2 = 30 y). On the other hand, due to the relatively low energy (0.66 MeV) of the emitted photons, they are suitable for an efficient radiation protection. The dose distribution around the sources is usually calculated by a specific program. However this program requires the knowledge of the position of sources within the applicator as well as the distribution of activity along them. The only way to learn these data is to make an X-ray picture of applicators and sources superimposed to the autoradiography of every source. It is difficult to achieve satisfactory radiographs with high dose rate sources with standard X-ray film material because autoradiography covers the structure of the radiographic shadow. The problem can be overcome either by applying a high intensity X-ray or gamma beam (originating from a radiotherapeutic machine), or by using photographic material of very low sensitivity, for example photographic paper. Combining both possibilities one can obtain satisfactory images. (author)

  11. Dosimetric evaluation of rectum and bladder using image-based CT planning and orthogonal radiographs with ICRU 38 recommendations in intracavitary brachytherapy

    Directory of Open Access Journals (Sweden)

    Jamema Swamidas

    2008-01-01

    Full Text Available The purpose is to compare CT-based dosimetry with International Commission on Radiation Units and Measurements (ICRU 38 bladder and rectum reference points in patients of carcinoma of uterine cervix treated with intracavitary brachytherapy (ICA. Twenty-two consecutive patients were evaluated. Orthogonal radiographs and CT images were acquired and transferred to PLATO planning system. Bladder and rectal reference points were identified according to ICRU 38 recommendations. Dosimetry was carried out based on Manchester system. Patient treatment was done using 192 Iridium high dose rate (HDR remote after-loading machine based on the conventional radiograph-based dosimetry. ICRU rectal and bladder point doses from the radiograph plans were compared with D 2 , dose received by 2 cm 3 of the organ receiving maximum dose from CT plan. V 2 , volume of organ receiving dose more than the ICRU reference point, was evaluated. The mean (±standard deviation volume of rectum and bladder was 60 (±28 cm 3 and 138 (±41 cm 3 respectively. The mean reference volume in radiograph and CT plan was 105 (±7 cm 3 and 107 (±7 cm 3 respectively. It was found that 6 (±4 cm3 of rectum and 16 (±10 cm 3 of bladder received dose more than the prescription dose. V2 of rectum and bladder was 7 (±1.7 cm 3 and 20.8 (±6 cm 3 respectively. Mean D 2 of rectum and bladder was found to be 1.11 (±0.2 and 1.56 (±0.6 times the mean ICRU reference points respectively. This dosimteric study suggests that comparison of orthogonal X-ray-based and CT-based HDR ICA planning is feasible. ICRU rectal point dose correlates well with maximum rectal dose, while ICRU bladder point underestimates the maximum bladder dose.

  12. Introduction of an alternative standardized radiographic measurement method to evaluate volar angulation in subcapital fractures of the 5th metacarpal

    Energy Technology Data Exchange (ETDEWEB)

    Hoffelner, Thomas; Resch, Herbert; Moroder, Philipp; Korn, Gundobert; Steinhauer, Felix [University of Salzburg, Department of Traumatology and Sports Injuries, Salzburg (Austria); Atzwanger, Joerg [University of Salzburg, Department of Radiology, Salzburg (Austria); Minnich, Bernd [University of Salzburg, Department of Organismic Biology, Salzburg (Austria); Tauber, Mark [Shoulder and Elbow Surgery ATOS Clinic Munich, Munich (Germany)

    2012-10-15

    The purpose of the present study was to compare the intra- and interobserver reliability of two different measurement methods for volar angulation of the 5th metacarpal (MC) in an attempt to establish a new standard measurement method to reduce interobserver discrepancies for therapeutic decisions. Twenty patients with subcapital fractures of the 5th MC were radiologically investigated. Imaging consisted of a radiographs in antero-posterior and precise lateral view in addition to a CT scan of the 5th MC. Measurement of volar angulation was accomplished using the conventional and the shaft articular surface (SAS) method. The measurements of five investigators were exported to a spreadsheet for statistical analysis to evaluate the intra-and interobserver reliability. The conventional technique showed large differences among the investigators and poor interobserver reliability (W = 0.328 and 0.307) both at injury (p = 0.001) and at follow-up (p = 0.189). The intraobserver concordance of all investigators showed better results with the SAS than with the conventional technique. With the SAS technique, no statistically significant difference among the investigators could be detected at either the time of injury (p = 0.418) or at follow-up (p = 0.526) with excellent interobserver reliability (W = 0.051 and W = 0.041). Evaluation of volar angulation at follow-up using CT scans did not show any statistically significant difference between the techniques with better correlation among the observers with the SAS technique (p = 0.838). The interobserver correlation of volar angulation with lateral radiographs using the conventional technique was insufficient. Therefore, we recommend the use of the novel SAS technique as standardized measurement method which showed higher accuracy and interobserver reliability in order to facilitate the choice of adequate treatment option. (orig.)

  13. Introduction of an alternative standardized radiographic measurement method to evaluate volar angulation in subcapital fractures of the 5th metacarpal

    International Nuclear Information System (INIS)

    Hoffelner, Thomas; Resch, Herbert; Moroder, Philipp; Korn, Gundobert; Steinhauer, Felix; Atzwanger, Joerg; Minnich, Bernd; Tauber, Mark

    2012-01-01

    The purpose of the present study was to compare the intra- and interobserver reliability of two different measurement methods for volar angulation of the 5th metacarpal (MC) in an attempt to establish a new standard measurement method to reduce interobserver discrepancies for therapeutic decisions. Twenty patients with subcapital fractures of the 5th MC were radiologically investigated. Imaging consisted of a radiographs in antero-posterior and precise lateral view in addition to a CT scan of the 5th MC. Measurement of volar angulation was accomplished using the conventional and the shaft articular surface (SAS) method. The measurements of five investigators were exported to a spreadsheet for statistical analysis to evaluate the intra-and interobserver reliability. The conventional technique showed large differences among the investigators and poor interobserver reliability (W = 0.328 and 0.307) both at injury (p = 0.001) and at follow-up (p = 0.189). The intraobserver concordance of all investigators showed better results with the SAS than with the conventional technique. With the SAS technique, no statistically significant difference among the investigators could be detected at either the time of injury (p = 0.418) or at follow-up (p = 0.526) with excellent interobserver reliability (W = 0.051 and W = 0.041). Evaluation of volar angulation at follow-up using CT scans did not show any statistically significant difference between the techniques with better correlation among the observers with the SAS technique (p = 0.838). The interobserver correlation of volar angulation with lateral radiographs using the conventional technique was insufficient. Therefore, we recommend the use of the novel SAS technique as standardized measurement method which showed higher accuracy and interobserver reliability in order to facilitate the choice of adequate treatment option. (orig.)

  14. Advanced radiographic scanning, enhancement and electronic data storage

    International Nuclear Information System (INIS)

    Savoie, C.; Rivest, D.

    2003-01-01

    It is a well-known fact that radiographs deteriorate with time. Substantial cost is attributed to cataloguing and storage. To eliminate deterioration issues and save time retrieving radiographs, laser scanning techniques were developed in conjunction with viewing and enhancement software. This will allow radiographs to be successfully scanned and stored electronically for future reference. Todays radiographic laser scanners are capable Qf capturing images with an optical density of up to 4.1 at 256 grey levels and resolutions up to 4096 pixels per line. An industrial software interface was developed for the nondestructive testing industry so that, certain parameters such as scan resolution, number of scans, file format and location to be saved could be adjusted as needed. Once the radiographs have been scanned, the tiff images are stored, or retrieved into Radiance software (developed by Rivest Technologies Inc.), which will help to properly interpret the radiographs. Radiance was developed to allow the user to quickly view the radiographs correctness or enhance its defects for comparison and future evaluation. Radiance also allows the user to zoom, measure and annotate areas of interest. Physical cost associated with cataloguing, storing and retrieving radiographs can be eliminated. You can now successfully retrieve and view your radiographs from CD media or dedicated hard drive at will. For continuous searches and/or field access, dedicated hard drives controlled by a server would be the media of choice. All scanned radiographs will be archived to CD media (CD-R). Laser scanning with a proper acquisition interface and easy to use viewing software will permit a qualified user to identify areas of interest and share this information with his/her colleagues via e-mail or web data access. (author)

  15. The radiographer's role in child protection: Comparison of radiographers perceptions by use of focus groups

    International Nuclear Information System (INIS)

    Davis, Michaela; Reeves, Pauline

    2006-01-01

    The research presented in this paper is taken from a larger study whose aims were to devise a holistic picture of how diagnostic radiographers approach child protection issues and to explore how radiographers and other professionals see the role of radiographers in the chain of evidence in relation to child protection as this applies to children who present at the Imaging Department with suspected non-accidental injuries (NAI). A focus group methodology was used with focus groups being conducted in the United Kingdom and Republic of Ireland. The results indicated that both United Kingdom and Republic of Ireland radiographers agreed that they had a role in child protection; however, they identified a wide interpretation as to the extent of that role. Although radiographers in the United Kingdom and Republic of Ireland work within different legal systems there were themes identified which were common to both countries. Although radiographers referred to a duty to the child as to all patients, no radiographer specifically mentioned the system and child care law under which it is assumed they operate. This research revealed an area which would benefit from more detailed research using a wider audience. However, the study revealed a need for training in relation to possible NAI indicators and the correct procedure for documenting their suspicions and initiating an NAI referral

  16. British Standard method for determination of ISO speed and average gradient of direct-exposure medical and dental radiographic film/process combinations

    International Nuclear Information System (INIS)

    1983-01-01

    Under the direction of the Cinematography and Photography Standards Committee, a British Standard method has been prepared for determining ISO speed and average gradient of direct-exposure medical and dental radiographic film/film-process combinations. The method determines the speed and gradient, i.e. contrast, of the X-ray films processed according to their manufacturer's recommendations. (U.K.)

  17. The information spectrum as a measure of radiographic image quality and system performance

    International Nuclear Information System (INIS)

    Kanamori, H.; Matsumoto, M.

    1984-01-01

    The spectrum (spatial-frequency component) of the information capacity of a radiograph, here called the information spectrum, is offered as a measure of image quality and system performance. The information spectrum is a much more practical expression than information capacity by itself: it combines synthetically the contrast, the latitude, the sharpness and the granularity, and is expressed as a function of spatial frequency. The information spectrum can be readily calculated by using the dynamic density range and the MTF and noise Wiener spectrum at medium density range. A practical example is given. The appropriate system for each object can be selected by comparing the information spectral values of various imaging systems at the significant spatial frequency range predetermined for each object. (author)

  18. Optical versus radiographic magnification for fine-detail skeletal radiography

    International Nuclear Information System (INIS)

    Genant, H.K.; Doi, K.; Mall, J.C.

    1974-01-01

    Fine detail radiographic techniques for peripheral skeletal imaging have gained wide clinical acceptance. In this study, the imaging properties and clinical applications of the optical magnification technique, which employs fine-grain industrial film and a large focal spot, have been compared quantitatively and qualitatively with those of three slow screen-film techniques, namely, contact exposure with a large focal spot, 2X radiographic magnification with a 0.3 mm focal spot, and 4X radiographic magnification with a 50 μ focal spot. The modulation transfer functions (MTFs) of the recording systems and focal spots have been obtained and film sensitometry has been performed. Clinical comparisons for patients with metabolic, arthritic, and neoplastic skeletal disorders have been made. The results illustrate the superiority of the optical magnification technique over contact or 2X magnification techniques using slow screen-film systems. If a microfocus tube is used, however, direct radiographic magnification may provide images comparable in resolution, noise, and contrast to those made with the optical magnification technique, and at lower radiation exposure to the patient. (U.S.)

  19. An evidence based protocol for peer review of radiographer musculoskeletal plain film reporting

    International Nuclear Information System (INIS)

    Stephenson, Paul; Hannah, April; Jones, Helen; Edwards, Rosemary; Harrington, Kate; Baker, Sally-Anne; Fitzgerald, Nicole; Belfield, Jane

    2012-01-01

    Aims: Medical image interpretation by non-medically trained staff continues to court controversy. This article aims to show that any potential risks associated with radiographer reporting can be monitored and mitigated if a robust peer review system is introduced. A search of the evidence base illustrates a paucity of guidance on how reporting radiographers should be audited or how a peer review process should be implemented. A practical framework for designing a reporting radiographer peer review process is provided. Methods: Following a literature review, key issues faced when designing a peer review protocol were identified. The following questions are answered: How frequent should peer review take place? How many reports should be reviewed? How are reports selected for review? Who should peer review the radiographer reports? How should radiographer's reporting performance be measured? What standard of reporting is acceptable? Results: Details are provided of the process that has been used for over three years at a busy inner-city teaching hospital for auditing musculoskeletal plain film radiographer reporting. The peer review method presented is not intended to produce robust statistical data; it is a practical method of locally assessing the reporting competency. As such, our protocol should be viewed as part of a larger programme for continuing professional development. Conclusion: It is hoped that this practical protocol will encourage radiology departments to engage in a programme of peer review for reporting radiographers.

  20. Radiographic study on temporomandibular joint Arthrosis

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Dong Soo [Dept. of Radiology, College of Dentistry, Seoul National University , Seoul (Korea, Republic of)

    1980-11-15

    The author analysed the routine radiographic changes and clinical symptoms of 205 cases of temporomandibular joint arthrosis. The clinical symptoms of the patients were classified and the morphological changes of condylar head, articular eminence, and articular fossa were analyzed and discussed from radiographic view point. The positional change of condylar head and articular fossa relation in TMJ arthrosis were observed. The frequencies of coincidence between the site of complaints and the site of the abnormal images which could be detected were examined. The results were obtained as follows; 1. Bone erosion, deformity, marginal proliferation and sclerosis were selected from many abnormal images as the radiographic diagnostic criteria of TMJ arthritic lesions. 2. Abnormal radiographic findings were revealed in 150 cases (73.9%) of 205 total TMJ arthrosis cases and site with abnormal findings coincided with the site of complaints in 105 cases (70.7%) of 150 cases and coincidence rates were higher above fourth decades than below third decades. 3. Sclerosis of the abnormal radiographic findings could be found more often below third decades than above fourth decades. 4. The positional changes of condylar head were revealed in 176 cases (85.9%) of 205 total cases. 5. Pain complaints were revealed in 170 cases(82.9%) and clicking sounds were revealed in 120 cases (58.6%) of clinical symptoms of TMJ arthrosis. 6. No tendency was found so far the differential diagnosis between pain dysfunction syndrome and osteoarthrosis of TMJ.

  1. Radiographic study on temporomandibular joint Arthrosis

    International Nuclear Information System (INIS)

    Yoo, Dong Soo

    1980-01-01

    The author analysed the routine radiographic changes and clinical symptoms of 205 cases of temporomandibular joint arthrosis. The clinical symptoms of the patients were classified and the morphological changes of condylar head, articular eminence, and articular fossa were analyzed and discussed from radiographic view point. The positional change of condylar head and articular fossa relation in TMJ arthrosis were observed. The frequencies of coincidence between the site of complaints and the site of the abnormal images which could be detected were examined. The results were obtained as follows; 1. Bone erosion, deformity, marginal proliferation and sclerosis were selected from many abnormal images as the radiographic diagnostic criteria of TMJ arthritic lesions. 2. Abnormal radiographic findings were revealed in 150 cases (73.9%) of 205 total TMJ arthrosis cases and site with abnormal findings coincided with the site of complaints in 105 cases (70.7%) of 150 cases and coincidence rates were higher above fourth decades than below third decades. 3. Sclerosis of the abnormal radiographic findings could be found more often below third decades than above fourth decades. 4. The positional changes of condylar head were revealed in 176 cases (85.9%) of 205 total cases. 5. Pain complaints were revealed in 170 cases(82.9%) and clicking sounds were revealed in 120 cases (58.6%) of clinical symptoms of TMJ arthrosis. 6. No tendency was found so far the differential diagnosis between pain dysfunction syndrome and osteoarthrosis of TMJ.

  2. Image-based RSA: Roentgen stereophotogrammetric analysis based on 2D-3D image registration.

    Science.gov (United States)

    de Bruin, P W; Kaptein, B L; Stoel, B C; Reiber, J H C; Rozing, P M; Valstar, E R

    2008-01-01

    Image-based Roentgen stereophotogrammetric analysis (IBRSA) integrates 2D-3D image registration and conventional RSA. Instead of radiopaque RSA bone markers, IBRSA uses 3D CT data, from which digitally reconstructed radiographs (DRRs) are generated. Using 2D-3D image registration, the 3D pose of the CT is iteratively adjusted such that the generated DRRs resemble the 2D RSA images as closely as possible, according to an image matching metric. Effectively, by registering all 2D follow-up moments to the same 3D CT, the CT volume functions as common ground. In two experiments, using RSA and using a micromanipulator as gold standard, IBRSA has been validated on cadaveric and sawbone scapula radiographs, and good matching results have been achieved. The accuracy was: |mu |RSA but higher than in vivo standard RSA. Because IBRSA does not require radiopaque markers, it adds functionality to the RSA method by opening new directions and possibilities for research, such as dynamic analyses using fluoroscopy on subjects without markers and computer navigation applications.

  3. Operational parameters analysis of the radiographic technique through the modulation transfer function

    International Nuclear Information System (INIS)

    Motta, Mauricio Saldanha; Guimaraes, Ari Sauer

    1995-01-01

    The influence of the focal size and image magnification variations on the radiographic final image is studied. The analysis used the modulation transfer function for evaluating the ratio of the radiographic image amplitude and that of the inspected object. it was concluded that the increase of the focal size and of the magnifications are not good for the image quality. 3 refs., 4 figs., 1 tab

  4. Retropharyngeal Tendinitis: Radiographic and Magnetic Resonance Imaging Findings

    Energy Technology Data Exchange (ETDEWEB)

    Gelineck, J.; Salomonsen, M.; Hviid, C. [Aarhus Univ. Hospital (Denmark). Dept. of Radiology

    2006-10-15

    Purpose: To describe the magnetic resonance imaging (MRI) findings in retropharyngeal tendinitis. Material and methods: Within 1 year, four patients presenting with symptoms of retropharyngeal tendinitis were examined by radiography and MRI. Results: On MRI and radiographs, all patients had characteristic soft-tissue swellings and calcifications related to the tendon of the longus colli muscle situated inferior to the anterior arc of C1. MRI showed well-defined edema, with high signal in the retropharyngeal tissue anterior to C1-C5 on short T1 inversion recovery (STIR) sequences, low signal on T1-weighted sequences, and low signal in the calcification on both sequences. In addition, three patients had high signal intensity changes on STIR sequences in the atlantoaxial joint situated posterior to the anterior arc of C1. Conclusion: MRI is a sensitive and accurate method in the diagnosis of retropharyngeal tendinitis. A new finding in this condition is an effusion or synovitis in the anterior atlantoaxial joint. MRI is a valuable tool in differentiating retropharyngeal tendinitis from other diagnoses such as retropharyngeal abscess, pyogenic spondylitis, and spondyloarthropathy.

  5. Hand joint space narrowing and osteophytes are associated with magnetic resonance imaging-defined knee cartilage thickness and radiographic knee osteoarthritis: data from the Osteoarthritis Initiative.

    Science.gov (United States)

    Haugen, Ida K; Cotofana, Sebastian; Englund, Martin; Kvien, Tore K; Dreher, Donatus; Nevitt, Michael; Lane, Nancy E; Eckstein, Felix

    2012-01-01

    To evaluate whether features of radiographic hand osteoarthritis (OA) are associated with quantitative magnetic resonance imaging (MRI)-defined knee cartilage thickness, radiographic knee OA, and 1-year structural progression. A total of 765 participants in Osteoarthritis Initiative (OAI; 455 women, mean age 62.5 yrs, SD 9.4) obtained hand radiographs (at baseline), knee radiographs (baseline and Year 1), and knee MRI (baseline and Year 1). Hand radiographs were scored for presence of osteophytes and joint space narrowing (JSN). Knee radiographs were scored according to the Kellgren-Lawrence (KL) scale. Cartilage thickness in the medial and lateral femorotibial compartments was measured quantitatively from coronal FLASHwe images. We examined the cross-sectional and longitudinal associations between features of hand OA (total osteophyte and JSN scores) and knee cartilage thickness, 1-year knee cartilage thinning (above smallest detectable change), presence of knee OA (KL grade ≥ 3), and progression of knee OA (KL change ≥ 1) by linear and logistic regression. Both hand OA features were included in a multivariate model (if p ≤ 0.25) adjusted for age, sex, and body mass index (BMI). Hand JSN was associated with reduced knee cartilage thickness (ß = -0.02, 95% CI -0.03, -0.01) in the medial femorotibial compartment, while hand osteophytes were associated with the presence of radiographic knee OA (OR 1.10, 95% CI 1.03-1.18; multivariate models) with both hand OA features as independent variables adjusted for age, sex, and BMI). Radiographic features of hand OA were not associated with 1-year cartilage thinning or radiographic knee OA progression. Our results support a systemic OA susceptibility and possibly different mechanisms for osteophyte formation and cartilage thinning.

  6. Unicystic Jaw Lesions: A Radiographic Guideline

    Directory of Open Access Journals (Sweden)

    Giju George

    2010-01-01

    Full Text Available The unilocular radiolucencies remain the topic of much interest for the clinicians and histhopathologists for decades. Adequate use of diagnostic aids and careful observation will clinically help the dentist to arrive at a proper diagnosis and renders quality treatment to patients. Despite of the development of various cross-sectional imaging modalities, the radiograph still remains as the first and most important investigation. Jaw bone lesions, especially unilocular ones, are difficult to diagnose radiologically because of their similar radiographic appearance. It is, thus, very important for the clinician to have a sound knowledge of various radiographic features of the tooth and its supporting structures.

  7. Pre-procedural scout radiographs are unnecessary for routine pediatric fluoroscopic examinations

    Energy Technology Data Exchange (ETDEWEB)

    Creeden, Sean G.; Rao, Anil G.; Eklund, Meryle J.; Hill, Jeanne G.; Thacker, Paul G. [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States)

    2017-03-15

    Although practice patterns vary, scout radiographs are often routinely performed with pediatric fluoroscopic studies. However few studies have evaluated their utility in routine pediatric fluoroscopy. To evaluate the value of scout abdomen radiographs in routine barium or water-soluble enema, upper gastrointestinal (GI) series, and voiding cystourethrogram pediatric fluoroscopic procedures. We retrospectively evaluated 723 barium or water-soluble enema, upper GI series, and voiding cystourethrogram fluoroscopic procedures performed at our institution. We assessed patient history and demographics, clinical indication for the examination, prior imaging findings and impressions, scout radiograph findings, additional findings provided by the scout radiograph that were previously unknown, and whether the scout radiograph contributed any findings that significantly changed management. We retrospectively evaluated 723 fluoroscopic studies (368 males and 355 females) in pediatric patients. Of these, 700 (96.8%) had a preliminary scout radiograph. Twenty-three (3.2%) had a same-day radiograph substituted as a scout radiograph. Preliminary scout abdomen radiographs/same-day radiographs showed no new significant findings in 719 (99.4%) studies. New but clinically insignificant findings were seen in 4 (0.6%) studies and included umbilical hernia, inguinal hernia and hip dysplasia. No findings were found on the scout radiographs that would either alter the examination performed or change management with regard to the exam. Pre-procedural scout abdomen radiographs are unnecessary in routine barium and water-soluble enema, upper GI series, and voiding cystourethrogram pediatric fluoroscopic procedures and can be substituted with a spot fluoroscopic last-image hold. (orig.)

  8. Clinical image quality evaluation for panoramic radiography in Korean dental clinics

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Bo Ram; Choi, Da Hye; Huh, Kyung Hoe; Yi, Won Jin; Heo, Min Suk; Choi, Soon Chul; Bae, Kwang Hak; Lee, Sam Sun [School of Dentistry, Seoul National University, Seoul (Korea, Republic of)

    2012-09-15

    The purpose of this study was to investigate the level of clinical image quality of panoramic radiographs and to analyze the parameters that influence the overall image quality. Korean dental clinics were asked to provide three randomly selected panoramic radiographs. An oral and maxillofacial radiology specialist evaluated those images using our self-developed Clinical Image Quality Evaluation Chart. Three evaluators classified the overall image quality of the panoramic radiographs and evaluated the causes of imaging errors. A total of 297 panoramic radiographs were collected from 99 dental hospitals and clinics. The mean of the scores according to the Clinical Image Quality Evaluation Chart was 79.9. In the classification of the overall image quality, 17 images were deemed 'optimal for obtaining diagnostic information,' 153 were 'adequate for diagnosis,' 109 were 'poor but diagnosable,' and nine were 'unrecognizable and too poor for diagnosis'. The results of the analysis of the causes of the errors in all the images are as follows: 139 errors in the positioning, 135 in the processing, 50 from the radiographic unit, and 13 due to anatomic abnormality. Panoramic radiographs taken at local dental clinics generally have a normal or higher-level image quality. Principal factors affecting image quality were positioning of the patient and image density, sharpness, and contrast. Therefore, when images are taken, the patient position should be adjusted with great care. Also, standardizing objective criteria of image density, sharpness, and contrast is required to evaluate image quality effectively.

  9. Bone suppression increases the visibility of invasive pulmonary aspergillosis in chest radiographs.

    Directory of Open Access Journals (Sweden)

    Steven Schalekamp

    Full Text Available Chest radiographs (CXR are an important diagnostic tool for the detection of invasive pulmonary aspergillosis (IPA in critically ill patients, but their diagnostic value is limited by a poor sensitivity. By using advanced image processing, the aim of this study was to increase the value of chest radiographs in the diagnostic work up of neutropenic patients who are suspected of IPA.The frontal CXRs of 105 suspected cases of IPA were collected from four institutions. Radiographs could contain single or multiple sites of infection. CT was used as reference standard. Five radiologists and two residents participated in an observer study for the detection of IPA on CXRs with and without bone suppressed images (ClearRead BSI 3.2; Riverain Technologies. The evaluation was performed separately for the right and left lung, resulting in 78 diseased cases (or lungs and 132 normal cases (or lungs. For each image, observers scored the likelihood of focal infectious lesions being present on a continuous scale (0-100. The area under the receiver operating characteristics curve (AUC served as the performance measure. Sensitivity and specificity were calculated by considering only the lungs with a suspiciousness score of greater than 50 to be positive.The average AUC for only CXRs was 0.815. Performance significantly increased, to 0.853, when evaluation was aided with BSI (p = 0.01. Sensitivity increased from 49% to 66% with BSI, while specificity decreased from 95% to 90%.The detection of IPA in CXRs can be improved when their evaluation is aided by bone suppressed images. BSI improved the sensitivity of the CXR examination, outweighing a small loss in specificity.

  10. Preliminary analysis of doses to evaluate the image quality in radiographic examinations in veterinary radiology;Analise preliminar das doses para avaliacao da qualidade da imagem em exames radiograficos na radiologia veterinaria

    Energy Technology Data Exchange (ETDEWEB)

    Pinto, Ana Carolina B.C.F.; Dias, Mayara T.P.; Santos, Andrea C. [Universidade de Sao Paulo (USP), SP (Brazil). Faculdade de Medicina Veterinaria e Zootecnia; Melo, Camila S.; Furquim, Tania A.C. [Universidade de Sao Paulo (IEE/USP), SP (Brazil). Inst. de Eletrotecnica e Energia

    2009-07-01

    This work has as objective to promote the analysis of the radiological doses and quality of the image of the technical letter used for the accomplishment of thorax and coxal radiographic examination of animals of canine and feline species. The study was accomplished in the service of Diagnosis for Image in Veterinarian Hospital of Veterinary Medicine and Zootecnia College of University of Sao Paulo, in two conventional equipment. Initially, physical features of the animals and the technique used were collected for each one of the 188 radiographic examinations of thorax and 52 examinations of coxal. The animals were placed in different groups, according to their body weight. For each group, the averages for each feature were calculated: thickness of the radiographed region, tension, electric current, time of exhibition, current product electric-time, size of the used film, presence or absence of bucky and feature of focus (narrow or thick). On the basis of the averages of group M (of lesser weights that 5kg for cats and between 10,1kg and 20kg for dogs), was executed a physical analysis of the current technical letter, using the equipment: ionization chamber (to determinate the value of kerma in air), simulator objects (representative of the thickness of the animal) and three dispositive standards of test that evaluate space resolution, resolution in low contrast and contrast-detail. The obtained images were analyzed and compared for a physicist and a radiologist medical veterinary. The results had shown that the examinations supply dose considered high for techniques used mainly for coxal. The equipment A, although to supply higher doses, presents the better images for the majority of the projections. However, the study indicates that there are not exactly reference levels, but these examinations must pass for improvement of quality of image (author)

  11. Radiographic and MR Imaging Findings of the Spine after Bisphosphonate Treatment, in a Child with Idiopathic Juvenile Osteoporosis

    Directory of Open Access Journals (Sweden)

    Olympia Papakonstantinou

    2015-01-01

    Full Text Available Bisphosphonates are employed with increasing frequency in various pediatric disorders, mainly associated with osteoporosis. After cessation of bisphosphonate treatment in children, skeletal radiologic changes have been documented including dense metaphyseal lines of the long bones and “bone in bone” appearance of the vertebrae. However, the evolution of these radiographic changes has not been fully explored. We describe the MR imaging appearance of the spine that, to our knowledge, has not been previously addressed in a child with idiopathic juvenile osteoporosis who had received bisphosphonates and emphasize the evolution of the radiographic findings of the spine and pelvis over a four-year period.

  12. A scientific model to determine the optimal radiographer staffing component in a nuclear medicine department

    International Nuclear Information System (INIS)

    Shipanga, A.N.; Ellmann, A.

    2004-01-01

    Full text: Introduction: Nuclear medicine in South Africa is developing fast. Much has changed since the constitution of a scientific model for determining an optimum number of radiographer posts in a Nuclear Medicine department in the late 1980's. Aim: The aim of this study was to ascertain whether the number of radiographers required by a Nuclear Medicine department can still be determined according to the norms established in 1988. Methods: A quantitative study using non-experimental evaluation design was conducted to determine the ratios between current radiographer workload and staffing norms. The workload ratios were analysed using the procedures statistics of the Nuclear Medicine department at Tygerberg Hospital. Radiographers provided data about their activities related to patient procedures, including information about the condition of the patients, activities in the radiopharmaceutical laboratory, and patient related administrative tasks. These were factored into an equation relating this data to working hours, including vacation and sick leave. The calculation of Activity Standards and an annual Standard Workload was used to finally calculate the staffing requirements for a Nuclear Medicine department. Results: Preliminary data confirmed that old staffing norms cannot be used in a modern Nuclear Medicine department. Protocols for several types of study have changed, including the additional acquisition of tomographic studies. Interest in the use of time-consuming non-imaging studies has been revived and should be factored Into the equation. Conclusions: All Nuclear Medicine departments In South Africa, where the types of studies performed have changed over the past years, should look carefully at their radiographer staffing ratio to ascertain whether the number of radiographers needed is adequate for the current workload. (author)

  13. Development of a valid and reliable test to assess trauma radiograph interpretation performance

    International Nuclear Information System (INIS)

    Neep, M.J.; Steffens, T.; Riley, V.; Eastgate, P.; McPhail, S.M.

    2017-01-01

    Objectives: The purpose of this investigation was to develop and examine the preliminary validity and reliability among radiographers of a test to assess trauma radiograph interpretation performance suitable for use among health professionals. Methods: Stage 1 examined 14,159 consecutive appendicular and axial examinations from a hospital emergency department over a 12 month period to quantify a typical anatomical region case-mix of trauma radiographs. A sample of radiographic cases representative of affected anatomical regions was then developed into the Image Interpretation Test (IIT). Stage 2 involved prospective investigations of the IIT's reliability (inter-rater, intra-rater, internal consistency) and validity (concurrent) among 41 radiographers. Results: The IIT included 60 cases. The median (interquartile range) clinical experience of participants was 5 (2–10) years. Case scores were internally consistent (Cronbach's alpha = 0.90). Favourable inter-rater reliability (kappa > 0.70 for 58/60 cases, Intra-class correlation coefficient (ICC) > 0.99 for total score) and intra-rater reliability (kappa > 0.90 for 60/60 cases, ICC > 0.99 for total score) was observed. There was a positive association between radiographers' confidence in image interpretation and IIT score (coefficient = 1.52, r-squared = 0.60, p < 0.001). Conclusions: The IIT developed during this investigation included a selection of radiographic cases consistent with anatomical regions represented in an adult trauma case-mix. This study has also provided foundational preliminary evidence to support the reliability and validity of the IIT among radiographers. The findings suggest that it is possible to assess image interpretation performance of adult trauma radiographs with this test. - Highlights: • Development of an Image Interpretation Test (IIT). • Cases consistent with anatomical regions represented in a typical adult trauma case-mix. • Development of a

  14. Oblique radiograph for the detection of bone spurs in anterior ankle impingement

    International Nuclear Information System (INIS)

    Dijk, Niek C. van; Wessel, Ronald N.; Tol, Johannes L.; Maas, M.

    2002-01-01

    Objective: The aim of this study was to develop a radiographic view to detect anteromedial talotibial osteophytes that remain undetected on standard radiographs. Design and patients: In 10 cadaver specimens the maximal size was measured of anteromedial tibial osteophytes that remain undetected on a standard lateral radiograph projection, due to the presence of the anteromedial tibial rim. The average projection of the most prominent anterolateral tibial rim over the anteromedial rim was found to be 7.3 mm. A 7 mm barium-clay osteophyte was attached to this anteromedial rim of the distal tibia. Anteromedial osteophytes become most prominent on an oblique view, in which the radiographic beam is tilted into a 45 craniocaudal direction with the leg in 30 external rotation. This oblique view was compared with the findings of arthroscopic surgery in 25 consecutive patients with anterior ankle impingement syndrome. Results: Medially located tibial and talar osteophytes remained undetected on a standard lateral projection and became visible on the oblique anteromedial impingement (AMI) radiograph. Anterolateral tibial and talar osteophytes were well detected on a standard lateral radiograph projection but were invisible on the AMI view. There was a high correlation between the location of the osteophyte and the location of symptoms and the findings at arthroscopy. Conclusion: A combination of lateral and oblique radiographs can be used to differentiate between anteromedial and anterolateral bony ankle impingement. (orig.)

  15. Serum C-reactive Protein Levels Demonstrate Predictive Value for Radiographic and Magnetic Resonance Imaging Outcomes in Patients with Active Ankylosing Spondylitis Treated with Golimumab.

    Science.gov (United States)

    Braun, Jürgen; Baraliakos, Xenofon; Hermann, Kay-Geert A; Xu, Stephen; Hsu, Benjamin

    2016-09-01

    Serum C-reactive protein (CRP) associates with radiographic progression in patients with ankylosing spondylitis (AS) untreated with tumor necrosis factor (TNF) antagonists. We assessed correlations between serum CRP and radiographic progression/magnetic resonance imaging (MRI)-detected inflammation after 2 years of anti-TNF therapy. Patients with active AS receiving golimumab (GOL)/placebo through Week 16 (early escape) or Week 24 (crossover by design), followed by GOL through 4 years, had sera/images obtained through Week 208. Lateral spinal radiographs and spinal MRI were scored with the modified Stoke AS Spine Score (mSASSS) and the AS spine MRI activity (ASspiMRI-a) score, respectively. ANOVA assessed differences based on CRP levels and mSASSS progression. The relationships between CRP levels and mSASSS/ASspiMRI-a were assessed by Spearman correlation and logistic regression. Of the randomized GO-RAISE patients, 299 (84.0%) had pre- and posttreatment spinal radiographs. Larger proportions of patients with Week 104 CRP ≥ 0.5 mg/dl (n = 47) versus formation risk. Elevated CRP after 2 years of anti-TNF treatment correlated with greater radiographic progression risk at 4 years. Elevated CRP at baseline or Week 14/Week 24 of anti-TNF treatment weakly predicted subsequent radiographic progression and modestly predicted residual spinal inflammation in patients with AS treated with anti-TNF. Findings are useful regarding new treatment options in patients treated with anti-TNF. ClinicalTrials.gov: NCT00265083.

  16. Plantar calcaneal enthesophytes: new observations regarding sites of origin based on radiographic, MR imaging, anatomic, and paleopathologic analysis

    International Nuclear Information System (INIS)

    Abreu, M.R.; Chung, C.B.; Mendes, L.; Mohana-Borges, A.; Trudell, D.; Resnick, D.

    2003-01-01

    To determine the relationship between sites of calcaneal plantar enthesophytes and surrounding fascial and soft tissue structures using routine radiography, MR imaging, and data derived from cadaveric and paleopathologic specimens.Design and patients. Two observers analyzed the MR imaging studies of 40 ankles in 38 patients (35 males, 3 females; mean age 48.3 years) with plantar calcaneal enthesophytes that were selected from all the ankle MR examinations performed during the past year. Data derived from these MR examinations were the following: the size of the enthesophyte; its location in relation to the plantar fascia (PF) and flexor muscles; and the thickness and signal of the PF. The corresponding radiographs of the ankles were evaluated at a different time by the same observers for the presence or absence of plantar enthesophytes and, when present, their measurements. A third observer reviewed all the discordant observations of MR imaging and radiographic examinations. Two observers analyzed 22 calcaneal specimens with plantar enthesophytes at an anthropology museum to determine the orientation of each plantar enthesophyte. MR imaging of a cadaveric foot with a plantar enthesophyte with subsequent sagittal sectioning was performed to provide further anatomic understanding.Results. With regard to MR imaging, the mean size of the plantar enthesophytes was 4.41 mm (SD 2.4). Twenty (50%) enthesophytes were located above the PF, 16 (40%) between the fascia and abductor digiti minimi, flexor digitorum brevis and abductor hallucis muscles, and only one (3%) was located within the PF. In three (8%) cases the location was not determined. The size of enthesophytes seen with MR imaging and radiographs was highly correlated (P 0.8, kappa >0.9). Eleven of the 22 bone specimens had plantar enthesophytes oriented in the direction of the abductor digiti minimi and 11 oriented in the direction of the flexor digitorum brevis and PF. The cadaveric sections revealed different

  17. Plantar calcaneal enthesophytes: new observations regarding sites of origin based on radiographic, MR imaging, anatomic, and paleopathologic analysis

    Energy Technology Data Exchange (ETDEWEB)

    Abreu, M.R.; Chung, C.B.; Mendes, L.; Mohana-Borges, A.; Trudell, D.; Resnick, D. [Department of Radiology, Musculoskeletal Section, VA San Diego Healthcare System, 3350 La Jolla Village Drive, San Diego, CA 92161 (United States)

    2003-01-01

    To determine the relationship between sites of calcaneal plantar enthesophytes and surrounding fascial and soft tissue structures using routine radiography, MR imaging, and data derived from cadaveric and paleopathologic specimens.Design and patients. Two observers analyzed the MR imaging studies of 40 ankles in 38 patients (35 males, 3 females; mean age 48.3 years) with plantar calcaneal enthesophytes that were selected from all the ankle MR examinations performed during the past year. Data derived from these MR examinations were the following: the size of the enthesophyte; its location in relation to the plantar fascia (PF) and flexor muscles; and the thickness and signal of the PF. The corresponding radiographs of the ankles were evaluated at a different time by the same observers for the presence or absence of plantar enthesophytes and, when present, their measurements. A third observer reviewed all the discordant observations of MR imaging and radiographic examinations. Two observers analyzed 22 calcaneal specimens with plantar enthesophytes at an anthropology museum to determine the orientation of each plantar enthesophyte. MR imaging of a cadaveric foot with a plantar enthesophyte with subsequent sagittal sectioning was performed to provide further anatomic understanding.Results. With regard to MR imaging, the mean size of the plantar enthesophytes was 4.41 mm (SD 2.4). Twenty (50%) enthesophytes were located above the PF, 16 (40%) between the fascia and abductor digiti minimi, flexor digitorum brevis and abductor hallucis muscles, and only one (3%) was located within the PF. In three (8%) cases the location was not determined. The size of enthesophytes seen with MR imaging and radiographs was highly correlated (P<0.01). The interobserver agreement for all measurements was good (Pearson >0.8, kappa >0.9). Eleven of the 22 bone specimens had plantar enthesophytes oriented in the direction of the abductor digiti minimi and 11 oriented in the direction of the

  18. An investigation into work related stressors on diagnostic radiographers in a local district hospital

    International Nuclear Information System (INIS)

    Verrier, William; Harvey, Jane

    2010-01-01

    Extensive research on the effects of work related stress amongst healthcare professions and the NHS has been undertaken. However, very little is known about the incidence of stress amongst UK radiographers although the few studies which have been conducted indicate that the prevalence and impact of stress on radiographers are considerable. The purpose of this study was to examine work related stressors which affect diagnostic radiographers in the imaging department of a local district hospital. The study utilised the HSE Indicator and Analysis Tools for Work Related Stress. These tools are based upon the HSE Management Standards for Work Related Stress which identifies six areas that represent potential stress hazards if managed inadequately. Two free response questions and a comments box were appended to the Indicator Tool to gain further insights into the radiographers' experiences of work related stress. The results of the study indicated that the hazards associated with work related stress risk were not being optimally managed in the department. Areas of Managers' Support, Relationships, Role and Change represented the greatest risks. In addition, the radiographers cited staff shortages, heavy workload and volume of patients as the greatest sources of pressure at work and their most common recommendations to reduce stress at work were increased staffing, improved communication and more effective feedback systems.

  19. A system for diagnostic quality radiographic alignment of radiotherapy patients

    International Nuclear Information System (INIS)

    Gall, Kenneth P.; Zygmanski, Piotr; Thornton, Allan F.

    1996-01-01

    patients based on implanted fiducial markers for several years which relies on plane film radiographs and location of the fiducial marker positions with a digitizing tablet. The use of a digital imaging system eliminates the time needed to develop the radiographs, and increases the precision with which the fiducials can be located. Accuracy of repositioning phantoms using this technique are better than 0.5 mm and 0.5 degrees at one standard deviation. Accuracy obtained in routine clinical positioning of patients is less than one millimeter and one degree. Conclusion Using implanted radiopaque fiducials and a digital imaging system for aligning patients treated for intracranial or head and neck disease significantly reduces the time, while increasing the precision with which they can be properly positioned for external beam radiation therapy. This method can be employed to deliver radiation on a standard fractionation schedule with typical stereotactic radiosurgical precision while maintaining practical treatment times

  20. Chest radiographic findings in acute paraquat poisoning

    Energy Technology Data Exchange (ETDEWEB)

    Na, Gyeong Gyun; Lee, Mi Sook; Kim, Hee Jun; Sun, In O [Presbyterian Medical Center, Jeonju (Korea, Republic of)

    2016-01-15

    To describe the chest radiographic findings of acute paraquat poisoning. 691 patients visited the emergency department of our hospital between January 2006 and October 2012 for paraquat poisoning. Of these 691, we identified 56 patients whose initial chest radiographs were normal but who developed radiographic abnormalities within one week. We evaluated their radiographic findings and the differences in imaging features based on mortality. The most common finding was diffuse consolidation (29/56, 52%), followed by consolidation with linear and nodular opacities (18/56, 32%), and combined consolidation and pneumomediastinum (7/56, 13%). Pleural effusion was noted in 17 patients (30%). The two survivors (4%) showed peripheral consolidations, while the 54 patients (96%) who died demonstrated bilateral (42/54, 78%) or unilateral (12/54, 22%) diffuse consolidations. Rapidly progressing diffuse pulmonary consolidation was observed within one week on follow-up radiographs after paraquat ingestion in the deceased, but the survivors demonstrated peripheral consolidation.

  1. Application of artificial neural network in radiographic diagnosis

    International Nuclear Information System (INIS)

    Piraino, D.; Amartur, S.; Richmond, B.; Schils, J.; Belhobek, G.

    1990-01-01

    This paper reports on an artificial neural network trained to rate the likelihood of different bone neoplasms when given a standard description of a radiograph. A three-layer back propagation algorithm was trained with descriptions of examples of bone neoplasms obtained from standard radiographic textbooks. Fifteen bone neoplasms obtained from clinical material were used as unknowns to test the trained artificial neural network. The artificial neural network correctly rated the pathologic diagnosis as the most likely diagnosis in 10 of the 15 unknown cases

  2. Radiographic markers for measuring tibial rotation based on CT-reconstructed radiographs. An accuracy and feasibility study

    International Nuclear Information System (INIS)

    Hakimian, David; Khoury, Amal; Mosheiff, Rami; Liebergall, Meir; Weil, Yoram A.

    2018-01-01

    Malreduction in the axial plane (malrotation) following tibial fracture surgery is often undiagnosed. A few clinical and radiographic methods have been proposed for measuring tibial rotation intraoperatively, yet have failed to match the accuracy of computed tomography (CT). The aim of this study was to develop radiographic tools for future intraoperative assessment of the tibial shaft rotation profile. The setting was a laboratory computerized analysis. Twenty lower limb CT scans were used to construct a three-dimensional (3D) model using AMIRA copyright software. A virtual 3D cylinder was implanted in the posterior condylar line and in the transmalleolar axis. The 3D models were used to simulate four standard knee and ankle plain radiographs. On each radiograph, four landmarks were depicted by two observers and their relation with the cylinder was measured and analyzed for accuracy and reproducibility. A cadaveric lower leg was implanted with two Kirschner wires. A CT scan was performed in addition to 2D fluoroscopy. The simulated radiographs and the fluoroscopy were compared for accuracy. Measurement of the landmarks showed reliability in most of the knee anteroposterior and ankle mortise radiographs (coefficients of variation < 0.01 and = 0.01) respectively. Cadaveric measurement of the landmarks using real fluoroscopy and simulated radiographs were similar. To date, no reliable and common methods have been reported for the evaluation of tibial axial rotation. We propose a model in which simple radiographic landmarks can be used to calculate a 3D coordinate system that accurately assesses the axial rotation angle of the tibial shaft. (orig.)

  3. Radiographic markers for measuring tibial rotation based on CT-reconstructed radiographs. An accuracy and feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Hakimian, David; Khoury, Amal; Mosheiff, Rami; Liebergall, Meir; Weil, Yoram A. [Hadassah Hebrew University Hospital, Department of Orthopaedics, Jerusalem (Israel)

    2018-04-15

    Malreduction in the axial plane (malrotation) following tibial fracture surgery is often undiagnosed. A few clinical and radiographic methods have been proposed for measuring tibial rotation intraoperatively, yet have failed to match the accuracy of computed tomography (CT). The aim of this study was to develop radiographic tools for future intraoperative assessment of the tibial shaft rotation profile. The setting was a laboratory computerized analysis. Twenty lower limb CT scans were used to construct a three-dimensional (3D) model using AMIRA copyright software. A virtual 3D cylinder was implanted in the posterior condylar line and in the transmalleolar axis. The 3D models were used to simulate four standard knee and ankle plain radiographs. On each radiograph, four landmarks were depicted by two observers and their relation with the cylinder was measured and analyzed for accuracy and reproducibility. A cadaveric lower leg was implanted with two Kirschner wires. A CT scan was performed in addition to 2D fluoroscopy. The simulated radiographs and the fluoroscopy were compared for accuracy. Measurement of the landmarks showed reliability in most of the knee anteroposterior and ankle mortise radiographs (coefficients of variation < 0.01 and = 0.01) respectively. Cadaveric measurement of the landmarks using real fluoroscopy and simulated radiographs were similar. To date, no reliable and common methods have been reported for the evaluation of tibial axial rotation. We propose a model in which simple radiographic landmarks can be used to calculate a 3D coordinate system that accurately assesses the axial rotation angle of the tibial shaft. (orig.)

  4. Negative magnetic resonance imaging in three cases of anterior tibial cortex stress fractures

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Ralph; Moghal, M.; Newton, J.L.; Jones, N. [Oxford University Hospitals NHS Foundation Trust, Department of Sport and Exercise Medicine, Nuffield Orthopaedic Centre, Oxford (United Kingdom); Teh, J. [Oxford University Hospitals NHS Foundation Trust, Department of Radiology, Nuffield Orthopaedic Centre Oxford, Oxford (United Kingdom)

    2017-12-15

    Anterior mid-tibial cortex stress fractures (ATCSF) are uncommon and notoriously challenging to treat. They are termed high risk due to their predilection to prolonged recovery, nonunion and complete fracture. Early diagnosis is essential to avoid progression and reduce fracture complications. Imaging plays a key role in confirming the diagnosis. Magnetic resonance imaging (MRI) is accepted as the gold standard modality due to its high accuracy and nonionizing properties. This report describes three cases of ATCSFs in recreational athletes who had positive radiographic findings with no significant MRI changes. Two athletes had multiple striations within their tibias. Despite the radiographic findings, their severity of symptoms were low with mild or no tenderness on examination. Clinicians should be mindful that the ATCSFs may not present with typical acute stress fracture symptoms. We recommend that plain radiographs should be used as the first line investigation when suspecting ATCSFs. Clinicians should be aware that despite MRI being considered the gold standard imaging modality, we report three cases where the MRI was unremarkable, whilst radiographs and computed tomography confirmed the diagnosis. We urge clinicians to continue to use radiographs as the first line imaging modality for ATCSFs and not to directly rely on MRI. Those who opt directly for MRI may be falsely reassured causing a delay in diagnosis. (orig.)

  5. Negative magnetic resonance imaging in three cases of anterior tibial cortex stress fractures

    International Nuclear Information System (INIS)

    Smith, Ralph; Moghal, M.; Newton, J.L.; Jones, N.; Teh, J.

    2017-01-01

    Anterior mid-tibial cortex stress fractures (ATCSF) are uncommon and notoriously challenging to treat. They are termed high risk due to their predilection to prolonged recovery, nonunion and complete fracture. Early diagnosis is essential to avoid progression and reduce fracture complications. Imaging plays a key role in confirming the diagnosis. Magnetic resonance imaging (MRI) is accepted as the gold standard modality due to its high accuracy and nonionizing properties. This report describes three cases of ATCSFs in recreational athletes who had positive radiographic findings with no significant MRI changes. Two athletes had multiple striations within their tibias. Despite the radiographic findings, their severity of symptoms were low with mild or no tenderness on examination. Clinicians should be mindful that the ATCSFs may not present with typical acute stress fracture symptoms. We recommend that plain radiographs should be used as the first line investigation when suspecting ATCSFs. Clinicians should be aware that despite MRI being considered the gold standard imaging modality, we report three cases where the MRI was unremarkable, whilst radiographs and computed tomography confirmed the diagnosis. We urge clinicians to continue to use radiographs as the first line imaging modality for ATCSFs and not to directly rely on MRI. Those who opt directly for MRI may be falsely reassured causing a delay in diagnosis. (orig.)

  6. Development of a fully automated adaptive unsharp masking technique in digital chest radiograph

    International Nuclear Information System (INIS)

    Abe, Katsumi; Katsuragawa, Shigehiko; Sasaki, Yasuo

    1991-01-01

    We are developing a fully automated adaptive unsharp masking technique with various parameters depending on regional image features of a digital chest radiograph. A chest radiograph includes various regions such as lung fields, retrocardiac area and spine in which their texture patterns and optical densities are extremely different. Therefore, it is necessary to enhance image contrast of each region by each optimum parameter. First, we investigated optimum weighting factors and mask sizes of unsharp masking technique in a digital chest radiograph. Then, a chest radiograph is automatically divided into three segments, one for the lung field, one for the retrocardiac area, and one for the spine, by using histogram analysis of pixel values. Finally, high frequency components of the lung field and retrocardiac area are selectively enhanced with a small mask size and mild weighting factors which are previously determined as optimum parameters. In addition, low frequency components of the spine are enhanced with a large mask size and adequate weighting factors. This processed image shows excellent depiction of the lung field, retrocardiac area and spine simultaneously with optimum contrast. Our image processing technique may be useful for diagnosis of chest radiographs. (author)

  7. Analysis of several ways to minimize the scatter contribution in radiographic digital images of offshore pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Edmilson M.; Silva, Ademir X.; Lopes, Ricardo T., E-mail: emonteiro@nuclear.ufrj.b, E-mail: ademir@nuclear.ufrj.b, E-mail: Ricardo@lin.ufrj.b [Coordenacao dos Programas de Pos-Graduacao de Engenharia (PEN/COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Programa de Engenharia Nuclear; Correa, Samanda C.A., E-mail: scorrea@cnen.gov.b [Comissao Nacional de Energia Nuclear (DIAPI/CGMI/CNEN), Rio de Janeiro, RJ (Brazil). Coordenacao Geral de Instalacoes Medicas e Industriais. Div. de Aplicacoes Industriais

    2011-07-01

    The aim of this work is to evaluate, through MCNPX simulations, several ways to minimize the scatter contribution in radiographic digital images of offshore pipelines. The influence of liquid inside the pipes and water surrounded the pipelines in the scatter contribution will be analyzed. The use of lead screen behind the detector to reduce the backscattered radiation and filter between the radiation source and the pipes will be discussed. (author)

  8. Analysis of several ways to minimize the scatter contribution in radiographic digital images of offshore pipelines

    International Nuclear Information System (INIS)

    Souza, Edmilson M.; Silva, Ademir X.; Lopes, Ricardo T.; Correa, Samanda C.A.

    2011-01-01

    The aim of this work is to evaluate, through MCNPX simulations, several ways to minimize the scatter contribution in radiographic digital images of offshore pipelines. The influence of liquid inside the pipes and water surrounded the pipelines in the scatter contribution will be analyzed. The use of lead screen behind the detector to reduce the backscattered radiation and filter between the radiation source and the pipes will be discussed. (author)

  9. Computed radiography versus mobile direct radiography for bedside chest radiographs: impact of dose on image quality and reader agreement

    NARCIS (Netherlands)

    de Boo, D. W.; Weber, M.; Deurloo, E. E.; Streekstra, G. J.; Freling, N. J.; Dongelmans, D. A.; Schaefer-Prokop, C. M.

    2011-01-01

    To asses the image quality and potential for dose reduction of mobile direct detector (DR) chest radiography as compared with computed radiography (CR) for intensive care unit (ICU) chest radiographs (CXR). Three groups of age-, weight- and disease-matched ICU patients (n=114 patients; 50 CXR per

  10. Technique for fabrication of gradual standards of radiographic image blachening density

    International Nuclear Information System (INIS)

    Borovin, I.V.; Kondina, M.A.

    1987-01-01

    The technique of fabrication of gradual standards of blackening density for industrial radiography by contact printing from a negative is described. The technique is designed for possibilities of industrial laboratoriesof radiation defectoscopy possessing no special-purpose sensitometric equipment

  11. Computed tomography versus magnetic resonance imaging versus bone scintigraphy for clinically suspected scaphoid fractures in patients with negative plain radiographs

    NARCIS (Netherlands)

    Mallee, Wouter H.; Wang, Junfeng; Poolman, Rudolf W.; Kloen, Peter; Maas, Mario; de Vet, Henrica C. W.; Doornberg, Job N.

    2015-01-01

    In clinically suspected scaphoid fractures, early diagnosis reduces the risk of non-union and minimises loss in productivity resulting from unnecessary cast immobilisation. Since initial radiographs do not exclude the possibility of a fracture, additional imaging is needed. Computed tomography (CT),

  12. Comparison between subjective and quantitative methods for assessing the resolution limit of radiographic systems; Comparacao entre metodos subjetivos e quantitativos na medida da resolucao limite de sistemas radiograficos

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez, Matheus; Oliveira, Marcela de; Miranda, Jose R.A. [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Botucatu, SP (Brazil). Inst. de Biociencias de Botucatu; Pina, Diana R., E-mail: matheus@ibb.unesp.br [UNESP, Botucatu, SP (Brazil). Faculdade de Medicina. Dept. de Doencas Tropicais e Diagnostico por Imagem

    2012-07-01

    The aim of this study was to compare two ways of measuring the resolution limit of radiographic systems, one subjective and one quantitative. To this end, nine images were acquired with different radiographic techniques using a pattern of bars and aluminum plates. With these images were acquired modulation transfer function (MTF) through the edge image obtained by the aluminum plate - the MTF 10% was measured on all images - and the variation of these points, which was faced with the evaluation obtained by the resolution limit of the standard bar. Although we have observed a greater variation between measurements obtained using the bar-pattern, the simplicity of this measuring technique favors the common use of the same. We concluded that, to optimize the quality control of radiographic equipment, it is suggested to measure the MTF at least in periods of time while the annual pattern of bars to be used in shorter time periods to measure changes in resolution of the system. (author)

  13. Image quality indicators for radiography and recommendations for their use - 1966

    Energy Technology Data Exchange (ETDEWEB)

    1976-01-01

    This Standard covers dimensional requirements, materials, construction and marking of wire type and step/hole type image quality indicators for assessing quality of radiographs on materials from 3 mm to 250 mm thick. Standard models of each type; use of image quality indicators (with obtainable sensitivity values) and charts for calculations. (Metric)

  14. Quantitative analysis of alveolar bone change following implant placement using intraoral radiographic subtraction

    International Nuclear Information System (INIS)

    Kimura, Hiroyuki; Kanda, Shigenobu; Tanaka, Takemasa

    2002-01-01

    The purpose of this study was to develop a procedure for quantitative analysis using intraoral radiographs of alveolar bone after placement of dental implants and to consider the validity of the method. We evaluated the ten patients (2 males and 8 females, average age: 48.4 years-old), who were treated with dental implant operation in the site of mandibular molar region, since October of 1999 until September of 2000 in Kimura Dental Clinic (Kumamoto, Japan). We evaluated the intraoral radiographs taken pre- and post- operatively and at follow-up examination. To detect alveolar bone change on radiograph, we adopted the digital subtraction method. Although the radiographs were taken under an ordinary technique with cone indicator, we did not apply the standardized technique with fixing material customized for each patient. Therefore, we used geometric correction and density compensation before subtraction. We assessed the basic statistical values (mean, variance, kurtosis and skewness) of the region of interest (ROI) of the subtracted images. Also, we noted PPD (probing pocket depth) and BOP (bleeding on probing) at each site as indicators of clinical findings and all implanted sites were classified according to the PPD or BOP, i.e. PPD increased group ''PPD (+)'' and PPD stable group ''PPD (-)'', likewise BOP positive group ''BOP (+)'' and negative group ''BOP (-)''. We considered the statistical values of ROI in each group and compared these findings. Mean and variance values of PPD (+) were higher than those of PPD (-) and there was a significant difference in mean value (p=0.031). Similarly, mean and variance values of BOP (+) were statistically higher than those of BOP (-) (p=0.041 and p=0.0087, respectively). Concerning kurtosis and skewness, there was no difference between PPD (+) and PPD (-), or between BOP (+) and BOP (-). Using our method, the radiographs taken for follow-up examination could be assessed quantitatively. It is suggested that geometric

  15. A case of lanthanum carbonate ingestion thought to be phlebosclerotic colitis on CT imaging and abdominal radiograph

    International Nuclear Information System (INIS)

    Harris, K.; Balcam, S.

    2017-01-01

    A male admitted in the early hours of the morning, complained of a four week, right sided, non-radiating, dull and intermittent abdominal pain. Imaging suggested a diagnosis of phlebosclerotic colitis which was later discounted when the patients' history of lanthanum carbonate ingestion was examined. Phlebosclerotic colitis mostly affects the Asian population, and its cause is still not known, but can be associated with specific radiographic features. Collections of lanthanum may confuse a diagnosis of phlebosclerotic colitis as well as other factors such as voxel errors, photon starvation and movement. - Highlights: • PC can be non-specific, its cause unknown, diagnosis is often delayed. • PC depends on specific radiographic features. • Lanthanum Carbonate can collect within the lumen and confuses diagnosis. • Voxel errors, photon starvation and patient movement can displace densities.

  16. Reducing dose in paediatric CT: a preliminary study of radiographers' knowledge

    International Nuclear Information System (INIS)

    Heagney, J.; Lewis, S.; Chaffey, C.; Howlett, G.; Moran, A.; McLean, D.

    2003-01-01

    The objective of this study is to evaluate the responses of Australian radiographers in comparison with current literature on paediatric protocols and scanning recommendations in order to determine how and if paediatric Computed Tomography (CT) exposure reductions are taking place within Medical Imaging Departments. Subjects and Methods: The method involved a dual format; consisting of surveying 30 CT radiographers, and additionally, interviewing 5 senior CT radiographers. Of the 30 surveys completed, one was completed by a PDY radiographer, 7 by CT Senior radiographers and 22 by CT radiographers. The survey contained a range of questions about appropriate paediatric CT scanning parameters and protocols. Five CT Seniors were interviewed to ascertain the current level and opinion of training in paediatric protocols, in-house educational programs and the implementation of radiation dose saving parameters. Radiographers demonstrated reasonable ability to identify suitable paediatric protocols and believed the in-house CT protocols resident to their medical imaging department to be adequate, despite many utilising exposures higher than those from recommended literature. The interviews revealed that no further training in CT paediatric dose reduction was currently available, however survey responses indicated that further training would be beneficial. This study demonstrates that radiographers are aware of the need to reduce exposure parameters for paediatric CT and tend to follow protocols in place within their workplace, regardless of suitability and patient needs. Copyright (2003) Australian Institute of Radiography

  17. Reducing dose in paediatric CT: a preliminary study of radiographers' Knowledge

    International Nuclear Information System (INIS)

    Heagney, Jillian; Lewis, Sarah; Chaffey, Clare; Howlett, Genevieve; Moran, Alexander; McLean, Donald

    2003-01-01

    The objective of this study is to evaluate the responses of Australian radiographers in comparison with current literature on paediatric protocols and scanning recommendations in order to determine how and if paediatric Computed Tomography (CT) exposure reductions are taking place within Medical Imaging Departments. Subjects and Methods: The method involved a dual format; consisting of surveying 30 CT radiographers, and additionally, interviewing 5 senior CT radiographers. Of the 30 surveys completed, one was completed by a PDY radiographer, 7 by CT Senior radiographers and 22 by CT radiographers. The survey contained a range of questions about appropriate paediatric CT scanning parameters and protocols. Five CT Seniors were interviewed to ascertain the current level and opinion of training in paediatric protocols, in-house educational programs and the implementation of radiation dose saving parameters. Radiographers demonstrated reasonable ability to identify suitable paediatric protocols and believed the in-house CT protocols resident to their medical imaging department to be adequate, despite many utilising exposures higher than those from recommended literature. The interviews revealed that no further training in CT paediatric dose reduction was currently available, however survey responses indicated that further training would be beneficial. This study demonstrates that radiographers are aware of the need to reduce exposure parameters for paediatric CT and tend to follow protocols in place within their workplace, regardless of suitability and patient needs Copyright (2003) Australian Institute of Radiography

  18. CT outperforms radiographs at a comparable radiation dose in the assessment for spondylolysis.

    Science.gov (United States)

    Fadell, Michael F; Gralla, Jane; Bercha, Istiaq; Stewart, Jaime R; Harned, Roger K; Ingram, James D; Miller, Angie L; Strain, John D; Weinman, Jason P

    2015-07-01

    Lumbar spondylolysis, a unilateral or bilateral fracture at pars interarticularis, is a common cause of low back pain in children. The initial imaging study in the diagnosis of lumbar spondylolysis has historically been lumbar spine radiographs; however, radiographs can be equivocal or false-negative. Definitive diagnosis can be achieved with computed tomography (CT), but its use has been limited due to the dose of ionizing radiation to the patient. By limiting the z-axis coverage to the relevant anatomy and optimizing the CT protocol, we are able to provide a definitive diagnosis of fractures of the pars interarticularis at comparable or lower radiation dose than commonly performed lumbar spine radiographs. As there is no gold standard for the diagnosis of spondylolysis besides surgery, we compared interobserver agreement and degree of confidence to determine which modality is preferable. Sixty-two patients with low back pain ages 5-18 years were assessed for the presence of spondylolyis. Forty-seven patients were evaluated by radiography and 15 patients were evaluated by limited field-of-view CT. Both radiographic and CT examinations were assessed anonymously in random order for the presence or absence of spondylolyisis by six raters. Agreement was assessed among raters using a Fleiss Kappa statistic for multiple raters. CT provided a significantly higher level of agreement among raters than radiographs (P < 0.001). The overall Kappa for rater agreement with radiographs was 0.24, 0.34 and 0.40 for 2, 3 or 4 views, respectively, and 0.88 with CT. Interobserver agreement is significantly greater using limited z-axis coverage CT when compared with radiographs. Radiologist confidence improved significantly with CT compared to radiographs regardless of the number of views.

  19. CT outperforms radiographs at a comparable radiation dose in the assessment for spondylolysis

    Energy Technology Data Exchange (ETDEWEB)

    Fadell, Michael F.; Stewart, Jaime R.; Harned, Roger K.; Ingram, James D.; Miller, Angie L.; Strain, John D.; Weinman, Jason P. [Children' s Hospital Colorado, Department of Radiology, Aurora, CO (United States); University of Colorado Hospital, Department of Radiology, Aurora, CO (United States); Gralla, Jane [University of Colorado Denver, Department of Pediatrics, Aurora, CO (United States); Bercha, Istiaq [Children' s Hospital Colorado, Department of Radiology, Aurora, CO (United States)

    2015-07-15

    Lumbar spondylolysis, a unilateral or bilateral fracture at pars interarticularis, is a common cause of low back pain in children. The initial imaging study in the diagnosis of lumbar spondylolysis has historically been lumbar spine radiographs; however, radiographs can be equivocal or false-negative. Definitive diagnosis can be achieved with computed tomography (CT), but its use has been limited due to the dose of ionizing radiation to the patient. By limiting the z-axis coverage to the relevant anatomy and optimizing the CT protocol, we are able to provide a definitive diagnosis of fractures of the pars interarticularis at comparable or lower radiation dose than commonly performed lumbar spine radiographs. As there is no gold standard for the diagnosis of spondylolysis besides surgery, we compared interobserver agreement and degree of confidence to determine which modality is preferable. Sixty-two patients with low back pain ages 5-18 years were assessed for the presence of spondylolysis. Forty-seven patients were evaluated by radiography and 15 patients were evaluated by limited field-of-view CT. Both radiographic and CT examinations were assessed anonymously in random order for the presence or absence of spondylolysis by six raters. Agreement was assessed among raters using a Fleiss Kappa statistic for multiple raters. CT provided a significantly higher level of agreement among raters than radiographs (P < 0.001). The overall Kappa for rater agreement with radiographs was 0.24, 0.34 and 0.40 for 2, 3 or 4 views, respectively, and 0.88 with CT. Interobserver agreement is significantly greater using limited z-axis coverage CT when compared with radiographs. Radiologist confidence improved significantly with CT compared to radiographs regardless of the number of views. (orig.)

  20. CT outperforms radiographs at a comparable radiation dose in the assessment for spondylolysis

    International Nuclear Information System (INIS)

    Fadell, Michael F.; Stewart, Jaime R.; Harned, Roger K.; Ingram, James D.; Miller, Angie L.; Strain, John D.; Weinman, Jason P.; Gralla, Jane; Bercha, Istiaq

    2015-01-01

    Lumbar spondylolysis, a unilateral or bilateral fracture at pars interarticularis, is a common cause of low back pain in children. The initial imaging study in the diagnosis of lumbar spondylolysis has historically been lumbar spine radiographs; however, radiographs can be equivocal or false-negative. Definitive diagnosis can be achieved with computed tomography (CT), but its use has been limited due to the dose of ionizing radiation to the patient. By limiting the z-axis coverage to the relevant anatomy and optimizing the CT protocol, we are able to provide a definitive diagnosis of fractures of the pars interarticularis at comparable or lower radiation dose than commonly performed lumbar spine radiographs. As there is no gold standard for the diagnosis of spondylolysis besides surgery, we compared interobserver agreement and degree of confidence to determine which modality is preferable. Sixty-two patients with low back pain ages 5-18 years were assessed for the presence of spondylolysis. Forty-seven patients were evaluated by radiography and 15 patients were evaluated by limited field-of-view CT. Both radiographic and CT examinations were assessed anonymously in random order for the presence or absence of spondylolysis by six raters. Agreement was assessed among raters using a Fleiss Kappa statistic for multiple raters. CT provided a significantly higher level of agreement among raters than radiographs (P < 0.001). The overall Kappa for rater agreement with radiographs was 0.24, 0.34 and 0.40 for 2, 3 or 4 views, respectively, and 0.88 with CT. Interobserver agreement is significantly greater using limited z-axis coverage CT when compared with radiographs. Radiologist confidence improved significantly with CT compared to radiographs regardless of the number of views. (orig.)

  1. Digital radiographic assessment of coronary flow reserve

    International Nuclear Information System (INIS)

    Vogel, R.A.

    1985-01-01

    A method for measuring relative changes in regional blood flow using digital radiographic enhancement of selective coronary arteriography. Coronary flow reserve is measured in individual arterial distributions using the washin ratio of contrast appearance time under baseline and hyperemic conditions. Information is quantitatively presented in functional (parametric) image format. These images, termed contrast medium appearance pictures (CMAP), depict the transit of contrast through the arterial, myocardial and early venous stages. This process can be divided into three general phases: data acquisition, CMAP formation and CMAP analysis. The technique has evolved over its development period from a cine film-based technology which required substantial processing time to a real-time digital radiographic technique

  2. Visualisation of dental images

    International Nuclear Information System (INIS)

    Md Saion Salikin; Azuhar Ripin; Wan Hazlinda Ismail; Asmaliza Hashim; Norriza Mohd Isa; Suriany Sarmid

    2005-01-01

    Since the invention and the discovery of x-rays, physicians, surgeons and life scientists have been using images to diagnose and subsequently treat diseases. X-ray is also widely used in many imaging techniques to better understand basics anatomy, physiology and biology as well as testing and analytical work in physical science. In dentistry, x-ray technique has been employed to get a panoramic view of the whole teeth of a particular patient. A panoramic dental radiograph is very useful in dentistry for diagnostic purpose, denture preparation, as well as for orthodontic. Image visualisation is an important aspect especially for the dentists to analyse and proceed with a particulate dental treatment. In this project panoramic dental image obtained by using a standard phantom is visualised by using Interactive Data Language (IDL) software. A panoramic dental x-ray machine, Cranex3, is used to get a panoramic radiograph, which is subsequently digitized, by using Vidar digitizer (Sierra Plus). The 2D digitized image is enhance and apply other visualising techniques such as surface rendering and volume rendering technique using Interactive Data Language (IDL) software as a first step in 3D visualisation. In this paper, visualising of panoramic dental radiograph by using IDL is discussed in brief. (Author)

  3. Computerized detection of lung nodules in digital chest radiographs

    International Nuclear Information System (INIS)

    Giger, M.L.; Doi, K.; MacMahon, H.

    1987-01-01

    Detection of cancerous lung nodules in chest radiographs is one of the more important tasks performed by a radiologist. In addition, the ''miss rate'' associated with the radiographic detection of lung nodules is approximately 30%. A computerized scheme that alerts the radiologist to possible locations of lung nodules should allow this number of false-negative diagnoses to be reduced. The authors are developing a computer-aided nodule detection scheme based on a difference image approach. They attempt to eliminate the camouflaging background structure of the normal lung anatomy by creating, from a single-projection chest image, two images: one in which the signal-to-noise ratio (SNR) of the nodule is maximized and another in which that SNR is suppressed while the processed background remains essentially the same. Thus, the difference between these two processed images should consist of the nodule superimposed on a relatively uniform background in which the detection task may be simplified. This difference image approach is fundamentally different from conventional subtraction techniques (e.g., temporal or dual-energy subtraction) in that the two images which are subtracted arise from the same single-projection chest radiograph. Once the difference image is obtained, thresholding is performed along with tests for circularity, size and growth in order to extract the nodules. It should be noted that once an original chest image is input to the computer the nodule detection process is totally automated

  4. International Society of Radiographers and Radiological Technologists and radiation protection

    International Nuclear Information System (INIS)

    Yule, A.

    2001-01-01

    The ISRRT was formed in 1962 with 15 national societies and by the year 2000 has grown to comprise more than 70 member societies. The main objects of the organization are to: Improve the education of radiographers; Support the development of medical radiation technology worldwide; Promote a better understanding and implementation of radiation protection standards. The ISRRT has been a non-governmental organization in official relations with the World Health Organization (WHO) since 1967. It is the only international radiographic organization that represents radiation medicine technology and has more than 200 000 members within its 70 member countries. Representatives of the ISRRT have addressed a number of assemblies of WHO regional committees on matters relating to radiation protection and radiation medicine technology. In this way, the expertise of radiographers worldwide contributes to the establishment of international standards in vital areas, such as: Quality control; Legislation for radiation protection; Good practice in radiographic procedures; Basic radiological services. The ISRRT believes that good and consistent standards of practice throughout the world are essential

  5. Evaluation of underexposed conventional radiographs after digitization. Auswertung fehlbelichteter konventioneller Roentgenaufnahmen nach Digitalisierung

    Energy Technology Data Exchange (ETDEWEB)

    Wenz, W. (Freiburg Univ. (Germany). Abt. Roentgendiagnostik); Buitrago-Tellez, C. (Freiburg Univ. (Germany). Abt. Roentgendiagnostik); Moenig, H. (Freiburg Univ. (Germany). Inst. fuer Biophysik und Strahlenbiologie); Niemeier, R. (Digital Diagnostik Deutschland GmbH, Freiburg im Breisgau (Germany))

    1993-02-01

    Inadequate exposure of analogue radiographs is reported in the literature to occur in 5-25% of cases. Therefore, the present study was performed to test whether selective image processing after digitization could reveal diagnostic details on underexposed radiographs. In addition, the minimal exposure values required for diagnostic purposes after adequate image processing were studied. Phantom studies, organ preparations and measurements of physical parameters with decreasing exposure values were performed. The detection of anatomic and pathologic (nondisplaced fracture lines, microcalcification and renal stones) structures were evaluated by 12 readers. Radiographs with exposure values 20-40% lower than 'ideal' values can provide adequate diagnostic images after digital processing. The diagnostic information is significantly impaired with values under 50% of the correct exposure values. In conclusion, this method is adequate to save underexposed radiographs for diagnostic purposes and to avoid repeated examinations. (orig.)

  6. A study of the mandibular canal in digital panoramic radiographic images of a selected Korean population

    International Nuclear Information System (INIS)

    Kim, Jae Duk; Kim, Jin Soo

    2007-01-01

    To determine the more valuable information to detect the mandibular canal and the mental foramen in panoramic radiographs of a selected Korean population for the implant. This study analysed 288 panoramic radiographic images of patients taken at the Dental hospital of Chosun University retrospectively. Indirect digital panoramic X-ray machine (ProlineXC, PLANMECA, Finland) with processing by using Directview CR950 (Kodak, U.S.A.) and Direct digital panoramic X-ray machine (Promax, PLANMECA, Finland) were used for all exposures. All images were converted into Dicom format. The common position of the mental foramen was in line with the longitudinal axis of the second premolar (68.1%). The mental foramen was lower symmetrical in 81.8% of cases. The mandibular canal was not identified at anterior portion and discontinued with the mental foramen in 27.8% of all cases, in 42.4% identified with lower border line continued with the mental foramen, in 14.6% with both upper and lower border lines, and in 15.3% unilaterally identified with lower border line. Clinicians can estimate the upper border line of the mandibular canal from the confirmation of the mental foramen and the lower border line of the mandibular canal symmetrically on the panoramic radiography taken in adjusted midsaggital plane of patient's head

  7. Effects of ionic and nonionic contrast media on cardiohemodynamics and quality of radiographic image during canine angiography

    International Nuclear Information System (INIS)

    Nakamura, H.; Kurata, M.; Haruta, K.; Takeda, K.

    1994-01-01

    Cardiovascular responses and radiographic image quality during cerebral angiography, aortofemoral angiography and left ventriculography with nonionic ioxilan, iohexol or iopamidol were compared with those of ionic sodium meglumine diatrizoate in pentobarbital anesthetized dogs. Injection of all contrast media caused cardiovascular changes to a greater or lesser degree, e.g., hypotension, bradycardia, tachycardia, a decrease in left ventricular pressure (LVP) and its first derivative (dP/dt), and prolongation of the P-Q and Q-T intervals. Ionic diatrizoate had a greater effect on cardiovascular parameters than nonionic contrast media during angiography in all areas. Moreover, diatrizoate produced cardiac arrhythmias and prominent changes in blood rheology concerned with blood viscosity and deformability of the erythrocyte. The cause of various effects of contrast media seemed to lie mainly in osmolality, viscosity and partially ionic additives. The radiographic image quality of all of the contrast media used was similar, but nonionic ioxilan and iohexol with lower iodine content and low osmolality gave better radio opacity than ionic diatrizoate in cerebral angiography. These results suggested that nonionic contrast media should be recommended as a diagnostic tool for both animals and human patients in poor health

  8. Relationship between image plates physical structure and quality of digital radiographic images in weld inspections

    International Nuclear Information System (INIS)

    Ferreira de Oliveira, Davi; Silva, Aline S.S.; Machado, Alessandra S.; Gomes, Celio S.; Nascimento, Joseilson R.; Lopes, Ricardo T.

    2016-01-01

    In the last decades a new type of detector which is based on photostimulable luminescence was developed. There are currently many kinds of image plates (IPs) available on the market, originating from different manufacturers. Each kind of plate distinguishes itself from the others by its peculiar physical structure and composition, two factors which have a direct influence upon the quality of the digital radiographic images obtained through them. For this study, several kinds of IPs were tested in order to determine in which way such influence takes place. For this purpose, each kind of IP has been characterized and correlated to its response in the final image. The aim of this work was to evaluated procedures for employing Computed Radiography (CR) to welding inspections in laboratory conditions using the Simple Wall Simple Image Technique (SWSI). CR tests were performed in steel welded joins of thickness 5.33, 12.70 and 25.40 mm. It was used an X-Ray equipment as radiation source. The image quality parameters Basic Spatial Resolution (BSR), Normalized Signal-to-Noise Ratio (SNRN), contrast and detectability were evaluated. In order to determine in which way the IPs' properties are correlated to its response in the final image, the thickness of the sensitive layer was determined and the grain size and the elemental composition of this layer were evaluated. Based on the results drawn from this study, it is possible to conclude that the physical characteristics of IPs are essential for determining the quality of the digital radiography images acquired with them. Regarding the grain size and the thickness of the IPs' sensitive layers, we could determine that the dimensions of such parameters were smaller on the plates presenting higher BSR, SNRN and contrast. However, the image plates which produced images with the highest resolution have also proven to be the least sensitive ones. All these parameters have a direct influence in the detectability of the

  9. Xeroradiographic and radiographic anatomy of the channel catfish, Ictalurus punctatus

    International Nuclear Information System (INIS)

    Smith, S.A.; Smith, B.J.

    1994-01-01

    The purpose of this study was to provide an anatomic reference for the channel catfish (Ictalurus punctatus) using xeroradiography† and conventional radiography. The entire body of three adult fish was radiographed using standard xeroradiographic and conventional radiographic techniques. Two xeroradiographs and their corresponding conventional radiographs were selected, and the xeroradiographs labeled to illustrate the normal skeletal and soft-tissue anatomy of the channel catfish

  10. SU-E-J-50: An Evaluation of the Stability of Image Quality Parameters of the Elekta XVI and IView Imaging Systems

    International Nuclear Information System (INIS)

    Stanley, D; Papanikolaou, N; Gutierrez, A

    2015-01-01

    Introduction Quality assurance of the image quality for image guided localization systems is crucial to ensure accurate visualization and localization of target volumes. In this study, the long term stability of selected image parameters was assessed and evaluated for CBCT mode, planar radiographic kV mode and MV mode. Methods and Materials: The CATPHAN, QckV-1 and QC-3 phantoms were used to evaluate the image quality parameters. The planar radiographic images were analyzed in PIPSpro™ with spatial resolution (f30, f40, f50) being recorded. For XVI CBCT, Head and Neck Small20 (S20) and Pelvis Medium20 (M20) standard acquisition modes were evaluated for Uniformity, Noise, Spatial Resolution and HU constancy. Dose and kVp for the XVI were recorded using the Unfors RaySafe Xi system with the R/F Low Detector for the kV planar radiographic mode. Results A total of 20 and 10 measurements were acquired for the planar radiographic and CBCT systems respectively over a two month period. Values were normalized to the mean and the standard deviations (STD) were recorded. For the planar radiographic spatial resolution, the STD for f30, f40, f50 were 0.004, 0.002, 0.002 and 0.005, 0.007, 0.008 for the kV and MV, respectively. The average recorded dose for kV was 38.7±2.7 μGy. The STD of the evaluated metrics for the S20 acquisition were: 0.444(f30), 0.067(f40), 0.062(f50), 0.018(Water/poly-HU constancy), 0.028(uniformity) and 0.106(noise). The standard deviations for the M20 acquisition were: 0.108(f30), 0.073(f40), 0.091(f50), 0.008(Water/poly-HU constancy), 0.005(uniformity) and 0.005(noise). Using these, tolerances can be reported as a warning and action threshold of 1σ and 2σ. Conclusion A study was performed to assess the stability of the basic image quality parameters recommended by TG-142 for the Elekta XVI and iView imaging systems. Consistent imaging and dosimetric properties over the evaluated time frame were noted. This work was funded in part by the Cancer

  11. Peritendinous calcinosis of calcaneus tendon associated with dermatomyositis: correlation between conventional radiograph, ultrasound, magnetic resonance imaging and gross surgical pathology

    International Nuclear Information System (INIS)

    Rosa, Ana Claudia Ferreira; Gomide, Lidyane Marques de Paula; Lemes, Marcella Stival

    2006-01-01

    Interstitial calcinosis is an uncommon condition in which there is either localized or widely disseminated deposition of calcium in the skin, subcutaneous tissues, muscles, and tendons. Calcinosis is often associated with collagen diseases, scleroderma and dermatomyositis. The authors report a case of interstitial calcinosis associated with dermatomyositis studied with conventional radiograph, ultrasound and magnetic resonance imaging, and correlate the imaging findings with the results of surgical pathology gross examination. (author)

  12. Where Does It Lead? Imaging Features of Cardiovascular Implantable Electronic Devices on Chest Radiograph and CT

    Energy Technology Data Exchange (ETDEWEB)

    Lanzman, Rotem S.; Blondin, Dirk; Furst, Gunter; Scherer, Axel; R Miese, Falk; Kroepil, Patric [University of Duesseldorf, Medical Faculty, 40225 Duesseldorf (Germany); Winter, Joachim [University Hospital Duesseldorf, 40225 Duesseldorf (Germany); Abbara, Suhny [Massachusetts General Hospital, Boston, MA (US)

    2011-10-15

    Pacemakers and implantable cardioverter defibrillators (ICDs) are being increasingly employed in patients suffering from cardiac rhythm disturbances. The principal objective of this article is to familiarize radiologists with pacemakers and ICDs on chest radiographs and CT scans. Therefore, the preferred lead positions according to pacemaker types and anatomic variants are introduced in this study. Additionally, the imaging features of incorrect lead positions and defects, as well as complications subsequent to pacemaker implantation are demonstrated herein.

  13. Where Does It Lead? Imaging Features of Cardiovascular Implantable Electronic Devices on Chest Radiograph and CT

    International Nuclear Information System (INIS)

    Lanzman, Rotem S.; Blondin, Dirk; Furst, Gunter; Scherer, Axel; R Miese, Falk; Kroepil, Patric; Winter, Joachim; Abbara, Suhny

    2011-01-01

    Pacemakers and implantable cardioverter defibrillators (ICDs) are being increasingly employed in patients suffering from cardiac rhythm disturbances. The principal objective of this article is to familiarize radiologists with pacemakers and ICDs on chest radiographs and CT scans. Therefore, the preferred lead positions according to pacemaker types and anatomic variants are introduced in this study. Additionally, the imaging features of incorrect lead positions and defects, as well as complications subsequent to pacemaker implantation are demonstrated herein.

  14. Automatic Vertebral Fracture Assessment System (AVFAS) for Spinal Pathologies Diagnosis Based on Radiograph X-Ray Images

    Science.gov (United States)

    Mustapha, Aouache; Hussain, Aini; Samad, Salina Abd; Bin Abdul Hamid, Hamzaini; Ariffin, Ahmad Kamal

    Nowadays, medical imaging has become a major tool in many clinical trials. This is because the technology enables rapid diagnosis with visualization and quantitative assessment that facilitate health practitioners or professionals. Since the medical and healthcare sector is a vast industry that is very much related to every citizen's quality of life, the image based medical diagnosis has become one of the important service areas in this sector. As such, a medical diagnostic imaging (MDI) software tool for assessing vertebral fracture is being developed which we have named as AVFAS short for Automatic Vertebral Fracture Assessment System. The developed software system is capable of indexing, detecting and classifying vertebral fractures by measuring the shape and appearance of vertebrae of radiograph x-ray images of the spine. This paper describes the MDI software tool which consists of three main sub-systems known as Medical Image Training & Verification System (MITVS), Medical Image and Measurement & Decision System (MIMDS) and Medical Image Registration System (MIRS) in term of its functionality, performance, ongoing research and outstanding technical issues.

  15. Dual-energy imaging in full-field digital mammography: a phantom study

    International Nuclear Information System (INIS)

    Taibi, A; Fabbri, S; Baldelli, P; Maggio, C di; Gennaro, G; Marziani, M; Tuffanelli, A; Gambaccini, M

    2003-01-01

    A dual-energy technique which employs the basis decomposition method is being investigated for application to digital mammography. A three-component phantom, made up of plexiglas, polyethylene and water, was doubly exposed with the full-field digital mammography system manufactured by General Electric. The 'low' and 'high' energy images were recorded with a Mo/Mo anode-filter combination and a Rh/Rh combination, respectively. The total dose was kept within the acceptable levels of conventional mammography. The first hybrid images obtained with the dual-energy algorithm are presented in comparison with a conventional radiograph of the phantom. Image-quality characteristics at contrast cancellation angles between plexiglas and water are discussed. Preliminary results show that a combination of a standard Mo-anode 28 kV radiograph with a Rh-anode 49 kV radiograph provides the best compromise between image-quality and dose in the hybrid image

  16. Training and Validating a Deep Convolutional Neural Network for Computer-Aided Detection and Classification of Abnormalities on Frontal Chest Radiographs.

    Science.gov (United States)

    Cicero, Mark; Bilbily, Alexander; Colak, Errol; Dowdell, Tim; Gray, Bruce; Perampaladas, Kuhan; Barfett, Joseph

    2017-05-01

    Convolutional neural networks (CNNs) are a subtype of artificial neural network that have shown strong performance in computer vision tasks including image classification. To date, there has been limited application of CNNs to chest radiographs, the most frequently performed medical imaging study. We hypothesize CNNs can learn to classify frontal chest radiographs according to common findings from a sufficiently large data set. Our institution's research ethics board approved a single-center retrospective review of 35,038 adult posterior-anterior chest radiographs and final reports performed between 2005 and 2015 (56% men, average age of 56, patient type: 24% inpatient, 39% outpatient, 37% emergency department) with a waiver for informed consent. The GoogLeNet CNN was trained using 3 graphics processing units to automatically classify radiographs as normal (n = 11,702) or into 1 or more of cardiomegaly (n = 9240), consolidation (n = 6788), pleural effusion (n = 7786), pulmonary edema (n = 1286), or pneumothorax (n = 1299). The network's performance was evaluated using receiver operating curve analysis on a test set of 2443 radiographs with the criterion standard being board-certified radiologist interpretation. Using 256 × 256-pixel images as input, the network achieved an overall sensitivity and specificity of 91% with an area under the curve of 0.964 for classifying a study as normal (n = 1203). For the abnormal categories, the sensitivity, specificity, and area under the curve, respectively, were 91%, 91%, and 0.962 for pleural effusion (n = 782), 82%, 82%, and 0.868 for pulmonary edema (n = 356), 74%, 75%, and 0.850 for consolidation (n = 214), 81%, 80%, and 0.875 for cardiomegaly (n = 482), and 78%, 78%, and 0.861 for pneumothorax (n = 167). Current deep CNN architectures can be trained with modest-sized medical data sets to achieve clinically useful performance at detecting and excluding common pathology on chest radiographs.

  17. AFROC analysis of reporting radiographer's performance in CT head interpretation

    International Nuclear Information System (INIS)

    Lockwood, P.; Piper, K.

    2015-01-01

    Aim: A preliminary small scale study to assess the diagnostic performance of a limited group of reporting radiographers and consultant radiologists in clinical practice undertaking computed tomography (CT) head interpretation. Method: A multiple reader multiple case (MRMC) alternative free response receiver operating characteristic (AFROC) methodology was applied. Utilising an image bank of 30 CT head examinations, with a 1:1 ratio of normal to abnormal cases. A reference standard was established by double reporting the original reports using two additional independent consultant radiologists with arbitration of discordance by the researcher. Twelve observers from six southern National Health Service (NHS) trusts were invited to participate. The results were compared for accuracy, agreement, sensitivity, specificity. Data analysis used AFROC and area under the curve (AUC) with standard error. Results: The reporting radiographers results demonstrated a mean sensitivity rate of 88.7% (95% CI 82.3–95.1%), specificity 95.6% (96% CI 90.1–100%) and accuracy of 92.2% (95% CI 89.3–95%). The consultant radiologists mean sensitivity rate was 83.35% (95% CI 80–86.7%), specificity 90% (95% CI 86.7–93.3%) and accuracy of 86.65% (95% CI 83.3–90%). Observer performance between the two groups was compared with AFROC, AUC, and standard error analysis (p = 0.94, SE 0.202). Conclusion: The findings of this research indicate that within a limited study, a small group of reporting radiographers demonstrated high levels of diagnostic accuracy in the interpretation of CT head examinations that was equivalent to a small selection of consultant radiologists. - Highlights: • We assessed reporting radiographers and consultant radiologists in a clinical setting. • This was a small scale retrospective multi-reader multi-case multi-site study. • AFROC used lesion-based decisions rather than case-based decisions. • Within a limited study the observed performance was high in

  18. Influenza A H1N1 pneumonia: radiograph and CT features of children

    International Nuclear Information System (INIS)

    Cheng Hua; Duan Xiaomin; Peng Yun; Zeng Jinjin; Sun Guoqiang

    2010-01-01

    Objective: To explore the imaging features on chest radiograph and CT in children with Influenza A H1N1 pneumonia. Methods: The imaging data of chest radiograph and CT in six children with Influenza A H1N1 pneumonia confirmed by real-time RT-PCR assay was retrospectively analysis. All patients had chest radiograph at first examination and 4 of them re-examed. One children took CT. Results: All cases showed thick lung markings with varied degrees of pulmonary infiltration and interstitial changes on chest radiograph. Among them, 3 cases showed bilateral pulmonary infiltration and 3 cases showed infiltration in left lung; enlarged hilar was observed in 3 cases. The imaging findings of the pneumonia changed quickly during the follow-up accompanied with the improvement of clinical symptoms. The only one chest CT examination showed bilateral infiltration, multiple ground-glass opacities, small subpleural nodulars, right pleural effusion and lymphadenopathy of lung hila and mediastinum. Conclusions: Chest radiograph and CT revealed certain typical imaging features in the children with influenza A H1N1 pneumonia. However, the final diagnosis of influenza A H1N1 pneumonia still should be made based on epidemiology and laboratory examination. (authors)

  19. Does Tibial Slope Affect Perception of Coronal Alignment on a Standing Anteroposterior Radiograph?

    Science.gov (United States)

    Schwartz, Adam J; Ravi, Bheeshma; Kransdorf, Mark J; Clarke, Henry D

    2017-07-01

    A standing anteroposterior (AP) radiograph is commonly used to evaluate coronal alignment following total knee arthroplasty (TKA). The impact of coronal alignment on TKA outcomes is controversial, perhaps due to variability in imaging and/or measurement technique. We sought to quantify the effect of image rotation and tibial slope on coronal alignment. Using a standard extramedullary tibial alignment guide, 3 cadaver legs were cut to accept a tibial tray at 0°, 3°, and 7° of slope. A computed tomography scan of the entire tibia was obtained for each specimen to confirm neutral coronal alignment. Images were then obtained at progressive 10° intervals of internal and external rotation up to 40° maximum in each direction. Images were then randomized and 5 blinded TKA surgeons were asked to determine coronal alignment. Continuous data values were transformed to categorical data (neutral [0], valgus [L], and varus [R]). Each 10° interval of external rotation of a 7° sloped tibial cut (or relative internal rotation of a tibial component viewed in the AP plane) resulted in perception of an additional 0.75° of varus. The slope of the proximal tibia bone cut should be taken into account when measuring coronal alignment on a standing AP radiograph. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. The development of standard operating protocols for paediatric radiology

    International Nuclear Information System (INIS)

    Hardwick, J.; Mencik, C.; McLaren, C.; Young, C.; Scadden, S.; Mashford, P.; McHugh, K.; Beckett, M.; Calvert, M.; Marsden, P.J.

    2001-01-01

    This paper describes how the requirement for operating protocols for standard radiological practice was expanded to provide a comprehensive aide to the operator conducting a medical exposure. The protocols adopted now include justification criteria, patient preparation, radiographic technique, standard exposure charts, diagnostic reference levels and image quality criteria. In total, the protocols have been welcomed as a tool for ensuring that medical exposures are properly optimised. (author)

  1. Role of a radiographer in mammography- new perspective

    International Nuclear Information System (INIS)

    Malik, S.

    2006-01-01

    giving the background to breast cancer in kenya. The importance of public education. The significance of early detection of breast cancer and patient survival. the emphasis of change of mind set of machine oriented radiographer to a clinically focused role. this involves a better understanding of the breast, the disease pattern, clinical examination of the breast and correlation with radiographic findings. The importance of other imaging modalities used to supplement mammography

  2. Comparison between sodium hypochlorite and copper sulfate reducer in lightening of overexposed working length radiographs

    Directory of Open Access Journals (Sweden)

    Fatemeh Ezoddini Ardakani

    2015-12-01

    Full Text Available Objectives: The aims of this study were to test whether lightening of the overexposed radiographs improve determination of endodontic files length and whether lightened radiographs are comparable with ideally exposed radiographs. Material and Methods: Four dried human skull coated with soft tissue-equivalent wax used for exposing radiographs of the upper molars. First, the endodontic file was placed in full length of the root and four series of radiographs obtained. The time to expose the first series was unchanged (standard group but increased for the other three series.  Two series of overexposed radiographs set as test groups (one lightened with copper sulfate reducer and the other lightened with sodium hypochlorite and one series set as control group. Then the endodontic file placed 2mm short in the root and four series of radiographs obtained like the former. A viewer evaluated radiographs. ROC curves were obtained and areas under the curves were calculated. Sensitivity, specificity and Cohen’s kappa was calculated. Results: The average area under ROC curves was 1, 0.995,1 and 0.643 for the standard, Copper sulfate, sodium hypochlorite and the control group, respectively. Sodium hypochlorite show a better performance in terms of sensitivity and specificity compared to Copper sulfate. Differences between the test radiographs and standard and control radiographs were significant (p

  3. Benefits and unexpected artifacts of biplanar digital slot-scanning imaging in children

    Energy Technology Data Exchange (ETDEWEB)

    Blumer, Steven L. [Nemours/A.I duPont Hospital for Children, Department of Medical Imaging, Wilmington, DE (United States); Dinan, David [Nemours Children' s Hospital, Orlando, FL (United States); Grissom, Leslie E. [Nemours/Alfred I. duPont Hospital for Children, Department of Radiology, Wilmington, DE (United States)

    2014-07-15

    Biplanar digital slot-scanning allows for relatively low-dose orthopedic imaging, an advantage in imaging children given the growing concerns regarding radiosensitivity. We have used this system for approximately 1 year for orthopedic imaging of the spine and lower extremities. We have noted advantages of using the digital slot-scanning system when compared with computed radiographic and standard digital radiographic imaging systems, but we also found unexpected but common imaging artifacts that are the direct result of the imaging method and that have not been reported. This pictorial essay serves to familiarize radiologists with the advantages of the digital slot-scanning system as well as imaging artifacts common with this new technology. (orig.)

  4. Ergonomic strategies to improve radiographers' posture during mammography activities.

    Science.gov (United States)

    Cernean, Nicolai; Serranheira, Florentino; Gonçalves, Pedro; Sá Dos Reis, Cláudia

    2017-08-01

    To identify alternatives for radiographers' postures while performing mammography that can contribute to reduce the risk of work-related musculoskeletal disorders (WRMSDs). Radiographers' postures to positioning craniocaudal (CC) and mediolateral oblique (MLO) views were simulated without any intervention for three scenarios: radiographer/patient with similar statures, radiographer smaller than patient and radiographer taller than patient. Actions were taken to modify the postures: seated radiographer; patient on a step; seated patient; radiographer on a step. All the postures were analysed using kinovea 0.8.15 software and the angles were measured twice and classified according to European standard EN1005-4: 2005. The non-acceptable angles were measured mainly during MLO positioning when radiographer was taller than the patient: 139° and 120° for arm-flexion and abduction, 72° for trunk and -24° for head/neck-flexion. The introduction of alternative postures (radiographer seated), allowed improvements in posture (60° and 99° for arm flexion and abduction, 14° for trunk and 0° for head/neck flexion), being classified as acceptable. The alternative postures simulated have the potential to reduce the risk of developing WRMSDs when radiographers and patients have different statures. • Radiographers' postures in mammography can contribute to work-related musculoskeletal disorders • Non-acceptable posture was identified for MLO breast positioning (radiographer taller than patient) • Adapting posture to patient biotype reduces the WRMSD risk for radiographers.

  5. CNEN-NN 6.04 standard adaptation in Brazil for industrial radiographic work in occupied areas or public roads

    International Nuclear Information System (INIS)

    Teixeira, P.B.; Aquino, J.O. de; Souza, L.A. de

    1996-01-01

    The industrial radiographic work that uses mobile equipment in Brazil must be in compliance with the National Commission of Nuclear Energy (CNEN) Regulation CNEN-NN 6.04. It states that every works that employs radiographic equipment in occupied areas or public roads requires a specific radiation protection procedure. This procedure must be approved by the CNEN at least fifteen days before starting the job. It is not always possible to the users to get their licensing work at time, because the industrial radiography jobs need immediate actions. Furthermore, the CNEN-NN 6.04 Regulation does not specify what type of information the procedures should involve, so that some important information had been often missed, causing a delaying in the licensing procedures. The corrective and preventive actions taken by the CNEN to optimize this kind of jobs and to overcome bureaucratic difficulties are described. A standard radiation protection procedure is also presented. (authors). 2 refs., 2 tabs

  6. Applying a computer-aided scheme to detect a new radiographic image marker for prediction of chemotherapy outcome

    International Nuclear Information System (INIS)

    Wang, Yunzhi; Qiu, Yuchen; Thai, Theresa; Moore, Kathleen; Liu, Hong; Zheng, Bin

    2016-01-01

    To investigate the feasibility of automated segmentation of visceral and subcutaneous fat areas from computed tomography (CT) images of ovarian cancer patients and applying the computed adiposity-related image features to predict chemotherapy outcome. A computerized image processing scheme was developed to segment visceral and subcutaneous fat areas, and compute adiposity-related image features. Then, logistic regression models were applied to analyze association between the scheme-generated assessment scores and progression-free survival (PFS) of patients using a leave-one-case-out cross-validation method and a dataset involving 32 patients. The correlation coefficients between automated and radiologist’s manual segmentation of visceral and subcutaneous fat areas were 0.76 and 0.89, respectively. The scheme-generated prediction scores using adiposity-related radiographic image features significantly associated with patients’ PFS (p < 0.01). Using a computerized scheme enables to more efficiently and robustly segment visceral and subcutaneous fat areas. The computed adiposity-related image features also have potential to improve accuracy in predicting chemotherapy outcome

  7. Radiographic evaluations

    International Nuclear Information System (INIS)

    Williams, J.L.

    1988-01-01

    The author describes how to: perform a systematic evaluation of a chest radiograph; state the classic radiographic description of hyaline membrane disease; list the conditions that cause hyperaeration and describe the radiologic feature of hyperaeration; describe the radiograph of a patient with a congenital diaphragmatic hernia; identify optimum placement of an endotracheal tube, gastric feeding tube, and umbilical artery catheter on a radiograph; differentiate between pulmonary interstitial air and hyaline membrane disease; select radiographic features that would indicate the presence of a tension pneumothorax; describe a lateral decubitus projection and state the type of problem it is most often used to identify; explain the procedure used in obtaining a lateral neck radiograph and list two problems that may require this view; and describe the radiograph of a patient with cystic fibrosis

  8. Radiographic evaluation of the course and visibility of the mandibular canal

    International Nuclear Information System (INIS)

    Jung, Yun Hoa; Cho, Bong Hae

    2014-01-01

    This study was performed to investigate the course of the mandibular canal on panoramic radiography and the visibility of this canal on both panoramic radiography and cone-beam computed tomography (CBCT). The study consisted of panoramic radiographs and CBCT images from 262 patients. The course of the mandibular canal, as seen in panoramic radiographs, was classified into four types: linear, elliptical, spoon-shaped, and turning curves. The visibility of this canal from the first to the third molar region was evaluated by visually determining whether the mandibular canal was clearly visible, probably visible, or invisible. The visibility of the canal on panoramic radiographs was compared with that on CBCT images. Elliptical curves were most frequently observed along the course of the mandibular canal. The percentage of clearly visible mandibular canals was the highest among the spoon-shaped curves and the lowest among the linear curves. On panoramic radiographs, invisible mandibular canals were found in 22.7% of the examined sites in the first molar region, 11.8% in the second molar region, and 1.3% in the third molar region. On CBCT cross-sectional images, the mandibular canal was invisible in 8.2% of the examined sites in the first molar region, 5.7% in the second molar region, and 0.2% in the third molar region. The visibility of this canal was lower in the first molar region than in the third molar region. The mandibular canal presented better visibility on CBCT images than on panoramic radiographs.

  9. Skeletal changes mimicking intrathoracic disease on chest radiographs

    International Nuclear Information System (INIS)

    Gelderen, WFC van

    2009-01-01

    Full text: Various chest radiographs are illustrated to demonstrate features where bony changes may mimic intrathoracic disease. To confirm the skeletal origin and nature, further conventional radiographs often suffice, and the need for CT or scintigraphy may therefore be obviated. At the time of presentation for radiography of the chest, further pertinent clinical details can be obtained from the patient by the department staff, as required. All previous radiographs and radiological reports should be readily available. In order to add to the educational value of the 13 cases illustrated, all are presented in quiz format, with the answers and further images included in the text.

  10. Diffraction enhanced x-ray imaging

    International Nuclear Information System (INIS)

    Thomlinson, W.; Zhong, Z.; Johnston, R.E.; Sayers, D.

    1997-09-01

    Diffraction enhanced imaging (DEI) is a new x-ray radiographic imaging modality using synchrotron x-rays which produces images of thick absorbing objects that are almost completely free of scatter. They show dramatically improved contrast over standard imaging applied to the same phantoms. The contrast is based not only on attenuation but also the refraction and diffraction properties of the sample. The diffraction component and the apparent absorption component (absorption plus extinction contrast) can each be determined independently. This imaging method may improve the image quality for medical applications such as mammography

  11. MRI reporting by radiographers: Findings of an accredited postgraduate programme

    Energy Technology Data Exchange (ETDEWEB)

    Piper, Keith [Allied Heath Professions Department, Canterbury Christ Church University, North Holmes Road, Canterbury, Kent CT1 1QU (United Kingdom)], E-mail: keith.piper@canterbury.ac.uk; Buscall, Kaie [Allied Heath Professions Department, Canterbury Christ Church University, North Holmes Road, Canterbury, Kent CT1 1QU (United Kingdom); Thomas, Nigel [X-Ray Department, Trafford General Hospital, Manchester M41 5SL (United Kingdom)

    2010-05-15

    Aim: To analyse the objective structured examination (OSE) results of the first three cohorts of radiographers (n = 39) who completed an accredited postgraduate certificate (PgC) programme in reporting of general magnetic resonance imaging (MRI) investigations and to compare the agreement rates with those demonstrated for a small group of consultant radiologists. Method: Forty MRI investigations were used in the OSE which included the following anatomical areas and abnormal appearances: knee; meniscal/ligament injuries, bone bruises, effusions and osteochondral defects; lumbar spine: intervertebral disc morphology, vertebral collapse, tumours (bone and soft tissue), spinal stenosis and/or nerve root involvement; internal auditory meati (IAM): acoustic neuroma. Incidental findings included maxillary polyp, arachnoid cyst, renal cyst, hydroureter, pleural effusion and metastases (adrenal, lung, perirenal and/or thoracic spine). Sensitivity, specificity and total percentage agreement rates were calculated for all radiographers (n = 39) using all reports (n = 1560). A small representative subgroup of reports (n = 27) was compared to the three consultant radiologists' reports which were produced when constructing the OSE. Kappa values were estimated to measure agreement in four groups: consultant radiologists only; radiographers and each of the consultant radiologists independently. Results: The sensitivity, specificity and agreement rates for the three cohorts (combined) of radiographers were 99.0%, 99.0% and 89.2%, respectively. For the majority (5/9) of anatomical areas and/or pathological categories no significant differences (p < 0.05) were found between the mean Kappa scores (K = 0.47-0.76) for different groups of observers, whether radiographers were included in the group analysis or not. Where differences were apparent, this was in cases (4/9) where the variation was either not greater than found between radiologists and/or of no clinical significance

  12. Radiographic findings in tuberculosis of the calvarium

    Energy Technology Data Exchange (ETDEWEB)

    Patankar, T.; Varma, R.; Krishnan, A.; Prasad, S. [Dept. of Radiology, King Edward Memorial Hospital, Parel, Bombay (India); Desai, K. [Dept. of Neurosurgery, King Edward Memorial Hospital, Bombay (India); Castillo, M. [Dept. of Radiology, University of North Carolina School of Medicine, Chapel Hill, NC (United States)

    2000-07-01

    We reviewed the pattern of involvement of the calvarium by tuberculosis (TB) in five patients and the role of imaging in its management. Four patients presented with localised scalp swelling and one with generalized seizures. Radiographs revealed lucent lesions with minimal surrounding sclerosis in the frontal (2), parietal (2) and occipital (1) bones. CT showed lesions involving the entire thickness of the calvarium and accompanying contrast-enhancing soft tissue. The patient presenting with seizures had a ring-enhancing lesion in the parietal lobe in addition to the extra-axial lesions. Although radiographs in all cases demonstrated calvarial TB, CT showed the extent of the defect, involvement of adjacent soft tissues, and in one case an intra-axial lesion. Radiographs suffice for follow-up of these patients. (orig.)

  13. Limited magnetic resonance imaging in low back pain instead of plain radiographs: Experience with first 1000 cases

    International Nuclear Information System (INIS)

    McNally, Eugene G.; Wilson, David J.; Ostlere, Simon J.

    2001-01-01

    AIM: We report our experience with the first 1000 patients with non-traumatic low back pain (LBP) without radiculopathy undergoing limited sequence magnetic resonance imaging (MRI) instead of plain radiography. METHODS: Between January 1996 and December 1998, 1042 patients with low back pain unresponsive to conservative treatment were examined using a limited MR protocol comprising sagittal T1-weighted and STIR imaging. Plain radiographs were not performed. RESULTS: Malignancy, infection, vertebral fracture, spondylitis, pars defects and cord tumours were detected in 20%. Of the 82 osteoporotic vertebral fractures detected, 51 (62%) were recent and 31 had normal marrow signal indicating that they were old. Eighty pars defects were identified, 45(56%) had spondylolisthesis, 29(37%) were undisplaced and 6 (7%) had pars oedema only. Neoplastic disease was found in 17(8%) of which none was suspected before imaging. Benign neoplastic diseases such as vertebral AVM/haemangiomata were excluded. Twenty-one patients had a variety of disorders including ankylosing spondylitis (7), large vessel aneurysm (3), discitis (2), ovarian cyst (2), sequestered disc (2), sacral insufficiency fracture (2) and one patient each with burst fracture, retroperitoneal haematoma and a previously unsuspected horseshoe kidney. CONCLUSION: The majority of patients with LBP are best assessed clinically and imaging is usually not required. In patients with worrying symptoms, MRI with a limited protocol detects a greater number of abnormalities than previously reported studies using plain radiographs and has replaced plain radiography in our hospital. We report our experience with the first 1000 patients and highlight issues such as protocols, detection rates and communication issues. McNally E.G. et al. (2001)

  14. Comparative validation of the radiographic and tomographic measurement of patellar height

    Directory of Open Access Journals (Sweden)

    Marco Antonio Schueda

    2013-09-01

    Full Text Available OBJECTIVE: To evaluate and validate the radiographic measurement of patellar height with computerized tomography scans. METHODS: Measured the patellar height through the lateral radiographic image supported by one foot and sagittal tomographic view of the knee in extension, flexion of 20°, and quadriceps contraction of 40 patients (80 knees, asymptomatic and no history of knee injuries using Insall-Salvati index. There were 20 adult females and 20 adult males. RESULTS: The height patellar index was higher in women of all images taken, in proportion. There was no statistical difference of patellar height index between the radiographics and tomographics images. CONCLUSION: The Insall-Salvati index in females was higher in all cases evaluated. Furthermore, it is possible to measure the patellar height index during tomographic study without distorting the results obtained, using to define the presence of patella alta or patella baja.

  15. The importance of radiographic imaging in the microscopic assessment of bone tumors

    International Nuclear Information System (INIS)

    Larousserie, F.; Kreshak, J.; Gambarotti, M.; Alberghini, M.; Vanel, D.

    2013-01-01

    Introduction: Primary bone tumors are rare and require a multidisciplinary approach. Diagnosis involves primarily the radiologist and the pathologist. Bone lesions are often heterogeneous and the microscopic diagnostic component(s) may be in the minority, especially on core needle biopsies. Reactive processes, benign, and malignant tumors may have similar microscopic aspects. For these challenging cases, the correlation of microscopic and radiologic information is critical, or diagnostic mistakes may be made with severe clinical consequences for the patient. The purpose of this article is to explain how pathologists can best use imaging studies to improve the diagnostic accuracy of bone lesions. Diagnosis: Many bone lesions are microscopically and/or radiographically heterogeneous, especially those with both lytic and matrix components. Final diagnosis may require specific microscopic diagnostic features that may be present in the lesion, but not the biopsy specimen. A review of the imaging helps assess if sampling was adequate. The existence of a pre-existing bone lesion, syndrome (such as Ollier disease or multiple hereditary exostosis), or oncologic history may be of crucial importance. Finally, imaging information is very useful for the pathologist to perform accurate local and regional staging during gross examination. Conclusion: Close teamwork between pathologists, radiologists, and clinicians is of utmost importance in the evaluation and management of bone tumors. These lesions can be very difficult to interpret microscopically; imaging studies therefore play a crucial role in their accurate diagnosis

  16. The importance of radiographic imaging in the microscopic assessment of bone tumors

    Energy Technology Data Exchange (ETDEWEB)

    Larousserie, F., E-mail: frederique.larousserie@cch.aphp.fr [Université Paris Descartes, Sorbonne Paris Cité, Paris (France); Department of pathology, Rizzoli Institute, Bologna (Italy); Kreshak, J.; Gambarotti, M.; Alberghini, M.; Vanel, D. [Department of pathology, Rizzoli Institute, Bologna (Italy)

    2013-12-01

    Introduction: Primary bone tumors are rare and require a multidisciplinary approach. Diagnosis involves primarily the radiologist and the pathologist. Bone lesions are often heterogeneous and the microscopic diagnostic component(s) may be in the minority, especially on core needle biopsies. Reactive processes, benign, and malignant tumors may have similar microscopic aspects. For these challenging cases, the correlation of microscopic and radiologic information is critical, or diagnostic mistakes may be made with severe clinical consequences for the patient. The purpose of this article is to explain how pathologists can best use imaging studies to improve the diagnostic accuracy of bone lesions. Diagnosis: Many bone lesions are microscopically and/or radiographically heterogeneous, especially those with both lytic and matrix components. Final diagnosis may require specific microscopic diagnostic features that may be present in the lesion, but not the biopsy specimen. A review of the imaging helps assess if sampling was adequate. The existence of a pre-existing bone lesion, syndrome (such as Ollier disease or multiple hereditary exostosis), or oncologic history may be of crucial importance. Finally, imaging information is very useful for the pathologist to perform accurate local and regional staging during gross examination. Conclusion: Close teamwork between pathologists, radiologists, and clinicians is of utmost importance in the evaluation and management of bone tumors. These lesions can be very difficult to interpret microscopically; imaging studies therefore play a crucial role in their accurate diagnosis.

  17. Texture analysis of trabecular bone using conventional radiographs: medical imaging and osteoporosis

    International Nuclear Information System (INIS)

    Karunanithi, R.; Panicker, T.M.R.; Paul Korath, M.; Jagadeesan, K.; Ganesan, S.

    2008-01-01

    Osteoporosis is characterized by reduced bone mass, microstructural deterioration with advancing age, and an increase in fracture risk. The accurate clinical assessment of bone strength and fracture risk is important for management of bone loss diseases such as osteoporosis risk. From a clinical point of view, microarchitecture is an interesting aspect to study and define patterns of bone alterations with aging and pathology. Microarchitecture seems to be a determinant of bone fragility independent of bone density. Moreover, bone microarchitecture seems to be important to understand the mechanisms of bone fragility independent of bone density. Moreover bone microarchitecture seems to be important to understand the mechanisms of bone fragility as well as the action of the drugs used to prevent osteoporotic fractures. In the case of osteoporosis the bone texture of the trabecular network as it appears on the plain radiographs can be quantified by applying image processing tools. Among the factors conditioning bone strength and osteoporotic fractures, bone mineral density is the most important and the best studied. Though, other factors also play a role: macroarchitecture of bones, cortical thickness, quality of bone crystal and of collagen network and trabecular microarchitecture. The microarchitecture plays a major role, and is an aspect of the definition of osteoporosis. Therefore, it would be very helpful if these alterations could be measured in addition to bone mineral density with noninvasive techniques, such as radiographs, and to assess the status of the bone by texture analysis

  18. HipMatch: an object-oriented cross-platform program for accurate determination of cup orientation using 2D-3D registration of single standard X-ray radiograph and a CT volume.

    Science.gov (United States)

    Zheng, Guoyan; Zhang, Xuan; Steppacher, Simon D; Murphy, Stephen B; Siebenrock, Klaus A; Tannast, Moritz

    2009-09-01

    The widely used procedure of evaluation of cup orientation following total hip arthroplasty using single standard anteroposterior (AP) radiograph is known inaccurate, largely due to the wide variability in individual pelvic orientation relative to X-ray plate. 2D-3D image registration methods have been introduced for an accurate determination of the post-operative cup alignment with respect to an anatomical reference extracted from the CT data. Although encouraging results have been reported, their extensive usage in clinical routine is still limited. This may be explained by their requirement of a CAD model of the prosthesis, which is often difficult to be organized from the manufacturer due to the proprietary issue, and by their requirement of either multiple radiographs or a radiograph-specific calibration, both of which are not available for most retrospective studies. To address these issues, we developed and validated an object-oriented cross-platform program called "HipMatch" where a hybrid 2D-3D registration scheme combining an iterative landmark-to-ray registration with a 2D-3D intensity-based registration was implemented to estimate a rigid transformation between a pre-operative CT volume and the post-operative X-ray radiograph for a precise estimation of cup alignment. No CAD model of the prosthesis is required. Quantitative and qualitative results evaluated on cadaveric and clinical datasets are given, which indicate the robustness and the accuracy of the program. HipMatch is written in object-oriented programming language C++ using cross-platform software Qt (TrollTech, Oslo, Norway), VTK, and Coin3D and is transportable to any platform.

  19. Digital evaluation of the influence of interruption of the fixation process on radiographic contrast and base-plus-fog density in three commercial brands of radiographic films

    Directory of Open Access Journals (Sweden)

    Paula Verona Ragusa da Silva

    Full Text Available INTRODUCTION : With the interest in anticipating access to the result of intraoral radiography, the radiographic processing is frequently neglected, compromising image quality. OBJECTIVE : The aim of this study was to evaluate the influence of interrupting the fixation process on the radiographic contrast and base-plus-fog density (BPFD in three brands of periapical films. MATERIAL AND METHOD : Ninety radiographs were taken of an aluminum stepwedge and a lead plate for each brand, and they were divided according to the time of initial immersion in the fixative in: control group (without interrupting the fixing, 5, 10, 20, 30 and 40 seconds. During processing, films had the fixing stage stopped and were exposed to a negatoscope for 1 minute, then the fixation time of 10 minutes was completed. The radiographs were digitized and exported to Image Tool 3.0.software. RESULT : Kodak(r film showed no statistically significant differences between groups, while Agfa(r film presented difference in BPFD compared with Group 5 seconds, and Dentix(r film showed statistical difference in all groups in comparison with the control group. CONCLUSION : Under the conditions studied, Kodak(r film is not influenced by disruption of fixation as regards BPFD and image contrast, enabling early access to the results of radiographs, whereas Agfa(r film requires at least 10 seconds of initial fixation, and Dentix(r film obtains better results when the process of fixation is not interrupted.

  20. Segmentation of ribs in digital chest radiographs

    Science.gov (United States)

    Cong, Lin; Guo, Wei; Li, Qiang

    2016-03-01

    Ribs and clavicles in posterior-anterior (PA) digital chest radiographs often overlap with lung abnormalities such as nodules, and cause missing of these abnormalities, it is therefore necessary to remove or reduce the ribs in chest radiographs. The purpose of this study was to develop a fully automated algorithm to segment ribs within lung area in digital radiography (DR) for removal of the ribs. The rib segmentation algorithm consists of three steps. Firstly, a radiograph was pre-processed for contrast adjustment and noise removal; second, generalized Hough transform was employed to localize the lower boundary of the ribs. In the third step, a novel bilateral dynamic programming algorithm was used to accurately segment the upper and lower boundaries of ribs simultaneously. The width of the ribs and the smoothness of the rib boundaries were incorporated in the cost function of the bilateral dynamic programming for obtaining consistent results for the upper and lower boundaries. Our database consisted of 93 DR images, including, respectively, 23 and 70 images acquired with a DR system from Shanghai United-Imaging Healthcare Co. and from GE Healthcare Co. The rib localization algorithm achieved a sensitivity of 98.2% with 0.1 false positives per image. The accuracy of the detected ribs was further evaluated subjectively in 3 levels: "1", good; "2", acceptable; "3", poor. The percentages of good, acceptable, and poor segmentation results were 91.1%, 7.2%, and 1.7%, respectively. Our algorithm can obtain good segmentation results for ribs in chest radiography and would be useful for rib reduction in our future study.

  1. Imaging of implants on chest radiographs: a radiological perspective

    International Nuclear Information System (INIS)

    Burney, K.; Thayur, N.; Husain, S.A.; Martin, R.P.; Wilde, P.

    2007-01-01

    Endovascular and percutaneous techniques have emerged as alternatives to surgical management in the treatment for a wide range of congenital and acquired cardiac, non-vascular and vascular conditions. Consequently, there has been an increasing use of implants such as closure devices, vascular stents (coronary, aortic, pulmonary and superior vena cava) and non-vascular stents like oesophageal and tracheo-bronchial stents. A large number of percutaneously sited implants are used for treating congenital cardiac anomalies such as atrial septal defects (ASD), ventricular septal defects (VSD), and patent ductus arteriosus (PDA). These implants take many shapes and forms. The aim of this review is to demonstrate the radiographic appearances of the various types of cardiovascular, bronchial and oesophageal implants that are visible on plain films. A brief outline of the aims and indications of various implant procedures, the general appearance of the commonest types of implants, and the radiological procedures are discussed. All radiologists are likely to come across implanted devices in plain film reporting. Imaging can be useful in identifying the device, assessing the position, integrity, and for the identification of complications related directly to the implant

  2. Imaging of implants on chest radiographs: a radiological perspective

    Energy Technology Data Exchange (ETDEWEB)

    Burney, K [Department of Clinical Radiology, Bristol Royal Infirmary (United Kingdom); Thayur, N [Department of Clinical Radiology, Bristol Royal Infirmary (United Kingdom); Husain, S A [Department of Respiratory Medicine, Bristol Royal Infirmary (United Kingdom); Martin, R P [Department of Cardiology, Bristol Royal Hospital for Children, Bristol (United Kingdom); Wilde, P [Department of Clinical Radiology, Bristol Royal Infirmary (United Kingdom)

    2007-03-15

    Endovascular and percutaneous techniques have emerged as alternatives to surgical management in the treatment for a wide range of congenital and acquired cardiac, non-vascular and vascular conditions. Consequently, there has been an increasing use of implants such as closure devices, vascular stents (coronary, aortic, pulmonary and superior vena cava) and non-vascular stents like oesophageal and tracheo-bronchial stents. A large number of percutaneously sited implants are used for treating congenital cardiac anomalies such as atrial septal defects (ASD), ventricular septal defects (VSD), and patent ductus arteriosus (PDA). These implants take many shapes and forms. The aim of this review is to demonstrate the radiographic appearances of the various types of cardiovascular, bronchial and oesophageal implants that are visible on plain films. A brief outline of the aims and indications of various implant procedures, the general appearance of the commonest types of implants, and the radiological procedures are discussed. All radiologists are likely to come across implanted devices in plain film reporting. Imaging can be useful in identifying the device, assessing the position, integrity, and for the identification of complications related directly to the implant.

  3. Image quality of a Konica Regius 336 digital system in chest radiography

    International Nuclear Information System (INIS)

    Ostinelli, A.; Frigerio, M.; Monti, A.F.; Gelosa, S.; Tognoli, P.; Perniola, N.; Gozzi, G.

    2000-01-01

    Digital radiographic systems permit to optimize execution, depiction and storage of radiological images. Since a Regius 336 digital system (Konica Corp. Tokyo, Japan) devoted to chest radiography Department of S. Anna Hospital in Como, Italy, it was investigated its performance relative to image quality. Konica Regius 336 is a computed radiography system made of a phosphorescence detector plate which is scanned with an infrared semiconductor laser beam. The radiographic image obtained from the detector is subjected to image processing, which allows a stable output and the nonlinear curve typical of conventional radiographic systems. Image quality was assessed based on the following parameters: dose, contrast, noise and spatial resolution. As reference, it was assessed the same parameters on a Cronex 88 analogic chest-changer (DuPont Pharma, North Billerica, Mass, USA). The Regius 336 air kerma values were always higher than the analogic ones (about 10%), both with and without a chest phantom; noise was also greater than in analogic images, sometimes even doubled. The optical densities of a step wedge and the spatial resolution of the digital chest-changer are independent of the X-ray tube voltage consequent to broader optical latitude. Inversely, the analogic images of the wedges show great optical density variability as a function of the X-ray tube voltage (in a range of 2). The modulation transfer functions of the two systems have the same trend. The performance of the Konica Regius 336 is nearly equivalent to that of an analogic system. The main advantages of the digital system are a standard output, lower consumption of radiographic films, higher productiveness and better image quality standard level [it

  4. Analysis the findings of chest radiograph and CT scan in 217 acute thoracic trauma

    International Nuclear Information System (INIS)

    Huang Shaoying

    2005-01-01

    Objective: To evaluate chest radiograph and CT scan in assessing acute thoracic trauma. Methods: Retrospectively analyzed the findings of chest radiograph and CT scan in 217 cases of acute thoracic trauma and positive rate of each modality was compared. Results: The positive rate of rib and clavicle fracture was higher in chest radiograph than these in CT scan. But the positive rate of chest wall hematoma, mediastinum and subcutaneous emphysema, pneumothorax, hydropneumothorax, damage of lung parenchyma and traumatic pulmonary atelectasis was higher in CT scan than those in chest radiograph. Conclusion: The application of the combined imaging modalities improves assessing of acute thoracic trauma, because the imaging manifestation of the lesion is various. (authors)

  5. Radiographic testing of wood

    International Nuclear Information System (INIS)

    Osterloh, K.; Zscherpel, U.; Raedel, C.; Weidemann, G.; Meinel, D.; Goebbels, J.; Ewert, U.; Hasenstab, A.; Buecherl, T.

    2007-01-01

    Wood is an old and established consumption and construction material. It is still the most common material for constructing furniture, roofs, playgrounds and mine supports. In contrast to steel and concrete, wood warns of extreme loads by creaking. Its mechanical stability is more influenced by decay than by peripheral cracks. While external cracks are visible, internal decay by fungus growth is undetectable from outside. This may be a safety problem in supporting structures. The best analysis of the internal structure is provided by computed tomography, but this is also the most complex method, much more so than simple radiographic testing. However, the latter is made inaccurate by scattered radiation resulting from internal moisture. With the image processing options of digital radiographic techniques, the structural information can be separated effectively from noise. In contrast to X-ray and gamma radiography, neutron radiography provides information on the spatial distribution of moisture. In healthy wood, water is conducted in the sapwood while the hardwood is dry. Moisture in hardwood is caused by infestations, e.g. fungus growth. The contribution presents a comparative analysis of the available radiographic methods. (orig.)

  6. Image quality in the anteroposterior cervical spine radiograph: Comparison between moving, stationary and non-grid techniques in a lamb neck

    Energy Technology Data Exchange (ETDEWEB)

    Keating, Michelle [School of Health and Social Care, Faculty of Health and Life Sciences, University of the West of England, Stapleton, Bristol BS16 1DD (United Kingdom); Grange, Stuart, E-mail: Stuart2.Grange@uwe.ac.u [School of Health and Social Care, Faculty of Health and Life Sciences, University of the West of England, Stapleton, Bristol BS16 1DD (United Kingdom)

    2011-05-15

    Background: Cervical spine radiography is a commonly employed examination for degenerative disease and trauma in the cervical spine. Traditionally, the anteroposterior projection is undertaken with the use of an anti-scatter grid. Some practitioners appear to have rejected this practice in favour of a non-grid technique, possibly because of the dose saving it affords. It is necessary to determine if image quality in the cervical spine is significantly degraded and whether the omission of the grid is justified. Method: Using a slaughtered lamb neck as a model of the human neck triplicate radiographs were obtained using a non-grid, a stationary grid and a moving grid technique. Entrance surface dose and dose area product was measured for these techniques. Image quality in terms of contrast, sharpness and overall acceptability was evaluated by 9 independent and blinded observers. Results: A significant reduction in measured dose was observed when the non-grid technique was compared to stationary or moving grid techniques. A statistically significant reduction in image contrast, sharpness and acceptability was also seen in the non-grid compared to grid techniques. Conclusion: These results show evidence of significantly greater image quality in the presence of either a moving or stationary grid in the lamb model. As such they support the continued use of scatter rejection methods such as the anti-scatter grid in AP radiography of the human cervical spine, to optimise radiographic image quality in this critical structure.

  7. Image quality in the anteroposterior cervical spine radiograph: Comparison between moving, stationary and non-grid techniques in a lamb neck

    International Nuclear Information System (INIS)

    Keating, Michelle; Grange, Stuart

    2011-01-01

    Background: Cervical spine radiography is a commonly employed examination for degenerative disease and trauma in the cervical spine. Traditionally, the anteroposterior projection is undertaken with the use of an anti-scatter grid. Some practitioners appear to have rejected this practice in favour of a non-grid technique, possibly because of the dose saving it affords. It is necessary to determine if image quality in the cervical spine is significantly degraded and whether the omission of the grid is justified. Method: Using a slaughtered lamb neck as a model of the human neck triplicate radiographs were obtained using a non-grid, a stationary grid and a moving grid technique. Entrance surface dose and dose area product was measured for these techniques. Image quality in terms of contrast, sharpness and overall acceptability was evaluated by 9 independent and blinded observers. Results: A significant reduction in measured dose was observed when the non-grid technique was compared to stationary or moving grid techniques. A statistically significant reduction in image contrast, sharpness and acceptability was also seen in the non-grid compared to grid techniques. Conclusion: These results show evidence of significantly greater image quality in the presence of either a moving or stationary grid in the lamb model. As such they support the continued use of scatter rejection methods such as the anti-scatter grid in AP radiography of the human cervical spine, to optimise radiographic image quality in this critical structure.

  8. Quantification of pneumothorax volume on chest radiographs: comparison between the collins' and the axel's methods with three-dimensional CT as the standard of reference

    International Nuclear Information System (INIS)

    Lee, Chang Keun; Kim, Hyung Jin; Lee, Kyung Hee; Kim, Joung Taek; Kim, Kwang Ho; Suh, Chang Hae; Han, Heon

    1999-01-01

    The purpose of this study was twofold. In a preliminary study, we evaluated the accuracy of 3-D (three-dimensional) CT for the estimation of pneumothorax volume and for providing the optimal postprocessing method for clinical study. In the clinical study, we determined which of the two methods, Collins' and Axel's, was more accurate for the estimation of pneumothorax volume, as seen on chest radiographs, using 3-D CT as the standard of reference. In the preliminary study, 3-D CT was applied to phantoms and to four patients with pneumothorax using two different postprocessing methods, manual contour delineation and thresholding. In the clinical study, 3-D CT was performed in 13 patients with pneumothorax. For the purpose of evaluating conventional radiographs, a localizer scan was used for comparing the accuracy of Collins' method with that of Axel's method, with 3-D CT as the standard of reference. The preliminary study revealed that 3-D CT estimated pneumothorax volume with great accuracy and that manual contour delineation and thresholding measured volume equally well. Because of the shorter postprocessing time required with thresholding than with manual contour delineation (5 min versus 30 min), the former was used during clinical study. The results of this indicated close correlation between the measurements obtained using Collins' method on chest radiographs and those obtained by 3-D CT(r=0.95, p 0.05). 3-D CT can estimate pneumothorax volume with great accuracy. Collins' method is superior to Axel's method for the quantification of pneumothorax volume as seen on chest radiographs

  9. Breast surgical specimen radiographs: How reliable are they?

    International Nuclear Information System (INIS)

    Britton, P.D.; Sonoda, L.I.; Yamamoto, A.K.; Koo, B.; Soh, E.; Goud, A.

    2011-01-01

    Radiography of the excised surgical specimen following wire guided localisation of impalpable breast lesions is standard surgical practice. The aims of the study were to establish the reliability of the breast specimen radiograph (SR) in determining lesion excision and to determine whether the radiographic margin correlated with the histological margin. The clinical, imaging, SR and pathological details of 106 patients with a pre-operative diagnosis of breast cancer were retrospectively reviewed. The reliability of orientation was estimated and the appearance and distance from the mammographic abnormality to each radial margin were measured and correlated with surgical histological findings. The overall accuracy of the specimen radiograph in determining whether the mammographic lesion was present was 99%. The SR could be orientated 'very reliably' or 'reliably' in 80% of patients however in only 48% of patients did the closest margin on the SR correspond with the same nearest margin at final histology. A maximum measurement of 11 mm or more from the lesion to the specimen edge was associated with a 77% likelihood of having a clear final histological margin (taken as 5 mm or more) and if <11 mm a 58% chance of having involved final histological margins. There was however a wide overlap in the results with patients having an apparently wide SR margin but histologically involved margins and vice versa. The SR is reliable at determining whether the target lesion has been removed. The correlation of SR margin orientation and measurement with final histological measurement is however far less reliable.

  10. Influence of the beam divergence on the quality neutron radiographic images improved by Richardson-Lucy deconvolution

    International Nuclear Information System (INIS)

    Almeida, Gevaldo L. de; Silvani, Maria Ines; Lopes, Ricardo T.

    2010-01-01

    Full text: Images produced by radiation transmission, as many others, are affected by disturbances caused by random and systematic uncertainties. Those caused by noise or statistical dispersion can be diminished by a filtering procedure which eliminates high-frequencies associated to the noise, but unfortunately also those belonging to the signal itself. Systematic uncertainties, in principle, could be more effectively removed if one knows the spoiling convolution function causing the degradation of the image. This function depends upon the detector resolution and the non-punctual character of the source employed in the acquisition, which blur the image making a single point to appear as a spot with a vanishing edge. For an extended source, exhibiting however a reasonable parallel beam, the penumbra degrading the image would be caused by the unavoidable beam divergence. In both cases, the essential information to improve the degraded image is the law of transformation of a single point into a blurred spot, known as point spread function-PSF. Even for an isotropic system, where this function would have a symmetric bell-like shape, it is very difficult to obtain experimentally and to apply it to the data processing. For this reason it is usually replaced by an approximated analytical function such as a Gaussian or Lorentzian. In this work, the Richardson-Lucy deconvoultion has been applied to ameliorate thermal neutron radiographic images acquired with imaging plates using a Gaussian PSF as deconvolutor. Due to the divergence of the neutron beam, reaching 1 deg 16', the penumbra affecting the final image depends upon the gap object-detector. Moreover, even if the object were placed in direct contact with the detector the non-zero dimension of the object along the beam path would produce penumbrae of different magnitudes, i.e., the spatial resolution of the system would be dependent upon the object-detector arrangement. This means that the width of the PSF increases

  11. Dilemma of gonial angle measurement: Panoramic radiograph or lateral cephalogram

    Energy Technology Data Exchange (ETDEWEB)

    Radhakrishnan, Pillai Devu; Varma, Nilambur Kovilakam Sapna; Ajith, Vallikat Velath [Dept. of Orthodontics, Amrita School of Dentistry, Kochi (India)

    2017-06-15

    The purpose of this study was to evaluate the accuracy of panoramic imaging in measuring the right and left gonial angles by comparing the measured angles with the angles determined using a lateral cephalogram of adult patients with class I malocclusion. The gonial angles of 50 class I malocclusion patients (25 males and 25 females; mean age: 23 years) were measured using both a lateral cephalogram and a panoramic radiograph. In the lateral cephalograms, the gonial angle was measured at the point of intersection of the ramus plane and the mandibular plane. In the panoramic radiographs, the gonial angle was measured by drawing a line tangent to the lower border of the mandible and another line tangent to the distal border of the ascending ramus and the condyle on both sides. The data obtained from both radiographs were statistically compared. No statistically significant difference was observed between the gonial angle measured using the lateral cephalograms and that determined using the panoramic radiographs. Further, there was no statistically significant difference in the measured gonial angle with respect to gender. The results also showed a statistically insignificant difference in the mean of the right and the left gonial angles measured using the panoramic radiographs. As the gonial angle measurements using panoramic radiographs and lateral cephalograms showed no statistically significant difference, panoramic radiography can be considered in orthodontics for measuring the gonial angle without any interference due to superimposed images.

  12. Managing digitally formatted diagnostic image data

    International Nuclear Information System (INIS)

    Templeton, A.W.; Dwyer, S.J.

    1985-01-01

    Diagnostic radiologists are very comfortable using analog radiographic film and interpreting its recorded images. To improve patient care, the radiologist has sought the finest quality radiographic film for use with the best radiographic imaging systems. The proper choice and use of x-ray tubes, generators, film-screen combinations, and contrast media has occupied the professional attention of the radiologist since the inception of radiology. Image quality can be significantly improved with digitally formatted diagnostic imaging systems by providing dynamic ranges in excess of those possible with analog x-ray films. In a CT scanner, the digital acquisition and reconstruction system can obtain a dynamic range (contrast resolution) of 10,000 to 1. Digital subtraction angiography systems achieve 10-bit dynamic ranges for each of the acquired television frames. Increases in the dynamic ranges of the various imaging modalities have been coupled with improved spatial resolution. A digitally formatted image is a two-dimensional, numerical array of discrete image elements. Each picture element is called a pixel. Each pixel has a discrete size. Figure 15.1 illustrates a digitally formatted image depicting the spatial resolution, array size, and quantization or numerical range of the pixel values. Currently, 512 x 512 image arrays are standard. Development of 1024 x 1024 digital arrays are underway. Significant improvements have also been achieved in the rates at which digital diagnostic imaging data can be acquired, manipulated, and archived

  13. Segmentation of lung fields using Chan-Vese active contour model in chest radiographs

    Science.gov (United States)

    Sohn, Kiwon

    2011-03-01

    A CAD tool for chest radiographs consists of several procedures and the very first step is segmentation of lung fields. We develop a novel methodology for segmentation of lung fields in chest radiographs that can satisfy the following two requirements. First, we aim to develop a segmentation method that does not need a training stage with manual estimation of anatomical features in a large training dataset of images. Secondly, for the ease of implementation, it is desirable to apply a well established model that is widely used for various image-partitioning practices. The Chan-Vese active contour model, which is based on Mumford-Shah functional in the level set framework, is applied for segmentation of lung fields. With the use of this model, segmentation of lung fields can be carried out without detailed prior knowledge on the radiographic anatomy of the chest, yet in some chest radiographs, the trachea regions are unfavorably segmented out in addition to the lung field contours. To eliminate artifacts from the trachea, we locate the upper end of the trachea, find a vertical center line of the trachea and delineate it, and then brighten the trachea region to make it less distinctive. The segmentation process is finalized by subsequent morphological operations. We randomly select 30 images from the Japanese Society of Radiological Technology image database to test the proposed methodology and the results are shown. We hope our segmentation technique can help to promote of CAD tools, especially for emerging chest radiographic imaging techniques such as dual energy radiography and chest tomosynthesis.

  14. Radiographic film digitizing devices

    International Nuclear Information System (INIS)

    McFee, W.H.

    1988-01-01

    Until recently, all film digitizing devices for use with teleradiology or picture archiving and communication systems used a video camera to capture an image of the radiograph for subsequent digitization. The development of film digitizers that use a laser beam to scan the film represents a significant advancement in digital technology, resulting in improved image quality compared with video scanners. This paper discusses differences in resolution, efficiency, reliability, and the cost between these two types of devices. The results of a modified receiver operating characteristic comparison study of a video scanner and a laser scanner manufactured by the same company are also discussed

  15. Evaluation of X ray attenuation by means of radiographic images; Avaliacao da atenuacao da radiacao X por meio de imagens radiograficas

    Energy Technology Data Exchange (ETDEWEB)

    Barros, Frieda Saicla, E-mail: saicla@utfpr.edu.b [Universidade Tecnologica Federal do Parana (UTFPR), Curitiba, PR (Brazil); Paredes, Ramon S.C., E-mail: ramon@ufpr.b [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil); Godoi, Walmor C., E-mail: walmor.godoi@gmail.co [Faculdade de Tecnologia Camoes (FATEC), Curitiba, PR (Brazil); Souza, Gabriel Pinto de [Universidade Estadual Paulista (UNESP), SP (Brazil)

    2011-07-01

    This paper's main goal is to adopt a qualitative methodology to evaluate the attenuation of x-radiation through X-ray images in polymeric materials plus residual lead. To determinate the images it was initially used an experimental setup at the Laboratory for Materials Diagnostics LACTEC. These results correspond to a more qualitative analysis, even with quantitative answers. Through analysis of radiographic images we can measure the intensity of radiation that goes through the plate, making possible to establish a relationship between the attenuation coefficient and the thickness of the material. (author)

  16. Radiographic testing in concrete structures

    International Nuclear Information System (INIS)

    Oliveira, D. de

    1987-01-01

    The radiographic testing done in concrete structures is used to analyse the homogeneity, position and corrosion of armatures and to detect discontinuity in the concrete such as: gaps, cracks and segregations. This work develops a Image quality Indicator (IQI) with an adequated sensibility to detect discontinuites based on BS4408 norm. (E.G.) [pt

  17. Evaluating the role of the diagnostic research radiographer

    International Nuclear Information System (INIS)

    Reid, Karen; Edwards, Hazel

    2011-01-01

    The NHS has an increasingly strong focus on evidence-based medicine to underpin policy making and the development of a culture of evaluation and learning. Good quality research is the foundation for this ethos. Numbers of research projects and clinical trials involving imaging are increasing and therefore more radiographers are contributing to these studies but perhaps on some occasions they may be unaware. This paper describes the benefits of having a dedicated research radiographer within a radiology department to organise and monitor studies. We explain the procedures of the research process, the knowledge and skills that such a radiographer requires and the value of coordination and governance in developing a culture of research in a radiology department. We make suggestions to overcome perceived barriers to engaging with research and discuss the advantages and limitations of the role. Others who are considering appointing a dedicated research radiographer may find our experience helpful.

  18. Full-body digital radiographic imaging of the injured child

    African Journals Online (AJOL)

    radiographic exposure increasing the cumulative dose of ionising ... radiography system in the Trauma Unit at Red Cross War Memorial ..... that resveratrol and similar drugs will treat age-related disorders such as type 2 diabetes and cancer.

  19. Relationship between image plates physical structure and quality of digital radiographic images in weld inspections

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Davi F.; Silva, Aline S.S.; Machado, Alessandra S.; Gomes, Celio S.; Nascimento, Joseilson; Lopes, Ricardo T., E-mail: davi@lin.ufrj.br.br, E-mail: aline@lin.ufrj.br, E-mail: celio@lin.ufrj.br, E-mail: alemachado@lin.ufrj.br, E-mail: joseilson@lin.ufrj.br, E-mail: ricardo@lin.ufrj.br [Coordenacao dos Programas de Pos-Graduacao em Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Lab. de Instrumentacao Nuclear

    2015-07-01

    In the last decades a new type of detector which is based on photostimulable luminescence was developed. There are currently many kinds of image plates (IPs) available on the market, originating from different manufacturers. Each kind of plate distinguishes itself from the others by its peculiar physical structure and composition, two factors which have a direct influence upon the quality of the digital radiographic images obtained through them. For this study, several kinds of IPs were tested in order to determine in which way such influence takes place. For this purpose, each kind of IP has been characterized and correlated to its response in the final image. The aim of this work was to evaluate procedures for employing Computed Radiography (CR) to welding inspections in laboratory conditions using the Simple Wall Simple Image Technique (SWSI). Tests were performed in steel welded joins of thickness 5.33, 12.70 and 25.40 mm, using CR scanner and IPs available on the market. It was used an X-Ray equipment as radiation source. The image quality parameters Basic Spatial Resolution (BSR), Normalized Signal-to-Noise Ratio (SNR{sub N}), contrast and detectability were evaluated. In order to determine in which way the IPs' properties are correlated to its response in the final image, the thickness of the sensitive layer was determined and the grain size and the elemental composition of this layer were evaluated. Based on the results drawn from this study, it is possible to conclude that the physical characteristics of image plates are essential for determining the quality of the digital radiography images acquired with them. Regarding the chemical composition of the plates, it was possible to determine that, apart from the chemical elements that were expected to be found (Ba, I and Br), only two plates, with high resolution, do not have fluorine in their composition; the presence of Strontium was also detected in the chemical composition of the plates supplied by a

  20. Relationship between image plates physical structure and quality of digital radiographic images in weld inspections

    International Nuclear Information System (INIS)

    Oliveira, Davi F.; Silva, Aline S.S.; Machado, Alessandra S.; Gomes, Celio S.; Nascimento, Joseilson; Lopes, Ricardo T.

    2015-01-01

    In the last decades a new type of detector which is based on photostimulable luminescence was developed. There are currently many kinds of image plates (IPs) available on the market, originating from different manufacturers. Each kind of plate distinguishes itself from the others by its peculiar physical structure and composition, two factors which have a direct influence upon the quality of the digital radiographic images obtained through them. For this study, several kinds of IPs were tested in order to determine in which way such influence takes place. For this purpose, each kind of IP has been characterized and correlated to its response in the final image. The aim of this work was to evaluate procedures for employing Computed Radiography (CR) to welding inspections in laboratory conditions using the Simple Wall Simple Image Technique (SWSI). Tests were performed in steel welded joins of thickness 5.33, 12.70 and 25.40 mm, using CR scanner and IPs available on the market. It was used an X-Ray equipment as radiation source. The image quality parameters Basic Spatial Resolution (BSR), Normalized Signal-to-Noise Ratio (SNR N ), contrast and detectability were evaluated. In order to determine in which way the IPs' properties are correlated to its response in the final image, the thickness of the sensitive layer was determined and the grain size and the elemental composition of this layer were evaluated. Based on the results drawn from this study, it is possible to conclude that the physical characteristics of image plates are essential for determining the quality of the digital radiography images acquired with them. Regarding the chemical composition of the plates, it was possible to determine that, apart from the chemical elements that were expected to be found (Ba, I and Br), only two plates, with high resolution, do not have fluorine in their composition; the presence of Strontium was also detected in the chemical composition of the plates supplied by a

  1. Modeling dental radiographic systems

    International Nuclear Information System (INIS)

    Webber, R.L.

    1980-01-01

    The Bureau of Radiological Health has been actively collaborating with the Clinical Investigations Branch, NIDR, in applied research involving diagnostic use of ionizing radiation in dentistry. This work has centered on the search for alternatives to conventional radiographic systems in an attempt to improve diagnostic performance while reducing the required exposure. The basic approach involves analysis of factors limiting performance of properly defined diagnostic tasks and the modeling alternative systems with an eye toward increasing objective measures of performance. Previous collaborative work involved using a nonlinear model to compare various x-ray spectra. The data were expressed as brightness-contrast versus exposure for simulated tasks of clinical interest. This report supplements these findings by extending the number of parameters under investigation and modifying the mode of data display so that an actual radiographic image can be simulated on a television screen

  2. Radiographic examination protocol and patient dose in lateral cephalometric radiography in Korea

    International Nuclear Information System (INIS)

    Choi, Jin Woo

    2010-01-01

    To survey the radiographic examination protocol for lateral cephalometric radiographic examinations and to measure their patient doses in Korea and to compare the dose according to the size of hospital, the type of image receptor system, and the installation duration. The radiographic examination protocols (kVp, mA, and exposure time) for lateral cephalometric radiography were surveyed with 61 cephalometric radiographic equipments and their patient dose-area product (DAP) measured with a DAP meter (DIAMENTOR M4-KDK, PTW, Freiburg, Germany) for 51 cephalometric radiographic equipments. The radiographic examination protocols and patient doses were compared according to the size of hospital (university dental hospital, dental hospital, and dental clinic), the type of image receptor system (film-based, DR and CR type) and the installation duration, respectively. SPSS 12.0.1 for Windows (SPSS Inc., Chicago, USA) was used for independent t-test and ANOVA test. The average protocols were 77.0 kVp, 12.7 mA, 6.2 second for cephalometric radiography. The average patient dose (DAP) was 128.0 mGy cm2 and 3rd quartile dose (DAP) 161.1 mGy cm2 for cephalometric radiography for adult male. There was no statistically significant difference at average patient DAP according to the size of hospital, the type of image receptor system, and the installation duration, respectively. The average patient dose was 128.0 mGy cm2 and the third quartile patient dose 161.1 mGy cm2 for lateral cephalometric radiography for adult male in Korea.

  3. Radiographic findings in immunodeficiency

    International Nuclear Information System (INIS)

    Obregon, R.; Lynch, D.A.; Cink, T.M.; Newell, J.D.; Kirkpatrick, C.

    1991-01-01

    This paper reviews the chest radiographs and high-resolution CT (HRCT) scans in patients with immunodeficiency disorders and define the role of HRCT. Thirty-three cases were retrospectively graded according to the consensus of two radiologists. Patients with HIV seropositivity and asthma were excluded. HRCT was performed in 12 cases with standard techniques. Diagnoses included common variable hypogammaglobulinemia (n = 19), X-linked agammaglobulinemia (n = 4), chronic mucocutaneous candidiasis (n = 4), and selective immunoglobulin g deficiencies (n = 2). Chest radiographs showed bronchiectasis in 11 of 33 cases with a predominant lower lobe distribution (82%). Nodules were present in six cases and mucus plugs in four cases. HRCT showed bronchiectasis in nine of 12 cases; in five of these nine cases, bronchiectasis was not apparent on chest radiographs. Other HRCT findings included segmental air trapping (four of 12), mucus plugs (three of 12), hazy consolidation (four of 12), nodules (five of 12), and bronchiolectasis (two of 12). Therapy was altered in seven of 12 cases in which HRCT was performed. Most pertinent to clinical management were the presence of a thymoma (n = 1) and severe focal of diffuse bronchiectasis

  4. Conditional non-independence of radiographic image features and the derivation of post-test probabilities – A mammography BI-RADS example

    International Nuclear Information System (INIS)

    Benndorf, Matthias

    2012-01-01

    Bayes' theorem has proven to be one of the cornerstones in medical decision making. It allows for the derivation of post-test probabilities, which in case of a positive test result become positive predictive values. If several test results are observed successively Bayes' theorem may be used with assumed conditional independence of test results or with incorporated conditional dependencies. Herein it is examined whether radiographic image features should be considered conditionally independent diagnostic tests when post-test probabilities are to be derived. For this purpose the mammographic mass dataset from the UCI (University of California, Irvine) machine learning repository is analysed. It comprises the description of 961 (516 benign, 445 malignant) mammographic mass lesions according to the BI-RADS (Breast Imaging: Reporting and Data System) lexicon. Firstly, an exhaustive correlation matrix is presented for mammography BI-RADS features among benign and malignant lesions separately; correlation can be regarded as measure for conditional dependence. Secondly, it is shown that the derived positive predictive values for the conjunction of the two features “irregular shape” and “spiculated margin” differ significantly depending on whether conditional dependencies are incorporated into the decision process or not. It is concluded that radiographic image features should not generally be regarded as conditionally independent diagnostic tests.

  5. Radiographically Occult and Subtle Fractures: A Pictorial Review

    International Nuclear Information System (INIS)

    Jarraya, M.; Hayashi, D.; Roemer, F.W.; Crema, M.D.; Conlin, J.; Marra, M.D.; Guermazi, A.; Roemer, F.W.; Crema, M.D.; Diaz, L.; Conlin, J.; Jomaah, N.

    2013-01-01

    Radiographically occult and subtle fractures are a diagnostic challenge. They may be divided into (1) high energy trauma fracture, (2) fatigue fracture from cyclical and sustained mechanical stress, and (3) insufficiency fracture occurring in weakened bone (e.g., in osteoporosis and post radiotherapy). Independently of the cause, the initial radiographic examination can be negative either because the findings seem normal or are too subtle. Early detection of these fractures is crucial to explain the patients symptoms and prevent further complications. Advanced imaging tools such as computed tomography, magnetic resonance imaging, and scintigraphy are highly valuable in this context. Our aim is to raise the awareness of radiologists and clinicians in these cases by presenting illustrative cases and a discussion of the relevant literature.

  6. Development Of A Dynamic Radiographic Capability Using High-Speed Video

    Science.gov (United States)

    Bryant, Lawrence E.

    1985-02-01

    High-speed video equipment can be used to optically image up to 2,000 full frames per second or 12,000 partial frames per second. X-ray image intensifiers have historically been used to image radiographic images at 30 frames per second. By combining these two types of equipment, it is possible to perform dynamic x-ray imaging of up to 2,000 full frames per second. The technique has been demonstrated using conventional, industrial x-ray sources such as 150 Kv and 300 Kv constant potential x-ray generators, 2.5 MeV Van de Graaffs, and linear accelerators. A crude form of this high-speed radiographic imaging has been shown to be possible with a cobalt 60 source. Use of a maximum aperture lens makes best use of the available light output from the image intensifier. The x-ray image intensifier input and output fluors decay rapidly enough to allow the high frame rate imaging. Data are presented on the maximum possible video frame rates versus x-ray penetration of various thicknesses of aluminum and steel. Photographs illustrate typical radiographic setups using the high speed imaging method. Video recordings show several demonstrations of this technique with the played-back x-ray images slowed down up to 100 times as compared to the actual event speed. Typical applications include boiling type action of liquids in metal containers, compressor operation with visualization of crankshaft, connecting rod and piston movement and thermal battery operation. An interesting aspect of this technique combines both the optical and x-ray capabilities to observe an object or event with both external and internal details with one camera in a visual mode and the other camera in an x-ray mode. This allows both kinds of video images to appear side by side in a synchronized presentation.

  7. Development of a dynamic radiographic capability using high-speed video

    International Nuclear Information System (INIS)

    Bryant, L.E. Jr.

    1984-01-01

    High-speed video equipment can be used to optically image up to 2000 full frames per second or 12,000 partial frames per second. X-ray image intensifiers have historically been used to image radiographic images at 30 frames per second. By combining these two types of equipment, it is possible to perform dynamic x-ray imaging of up to 2,000 full frames per second. The technique has been demonstrated using conventional, industrial x-ray sources such as 150 kV and 300 kV constant potential x-ray generators, 2.5 MeV Van de Graaffs, and linear accelerators. A crude form of this high-speed radiographic imaging has been shown to be possible with a cobalt 60 source. Use of a maximum aperture lens makes best use of the available light output from the image intensifier. The x-ray image intensifier input and output fluors decay rapidly enough to allow the high frame rate imaging. Data are presented on the maximum possible video frame rates versus x-ray penetration of various thicknesses of aluminum and steel. Photographs illustrate typical radiographic setups using the high speed imaging method. Video recordings show several demonstrations of this technique with the played-back x-ray images slowed down up to 100 times as compared to the actual event speed. Typical applications include boiling type action of liquids in metal containers, compressor operation with visualization of crankshaft, connecting rod and piston movement and thermal battery operation. An interesting aspect of this technique combines both the optical and x-ray capabilities to observe an object or event with both external and internal details with one camera in a visual mode and the other camera in an x-ray mode. This allows both kinds of video images to appear side by side in a synchronized presentation

  8. Coke detection in furnaces tubes by radiographic examination

    International Nuclear Information System (INIS)

    Santos, I.S. dos

    1987-01-01

    The coke detection technique by radiographic examinations allows to quantify the coke in furnace coils of Petroleum refineries and petrochemical industries. The paper describes how was determined the radiographic parameters, the wall apparent thickness calculation, the distance source-film, the position of the source and films, the chosen of films and the calculation of exposure time, aiming to obtain high producticity and good quality image. This technique is being used and improved for more than two years with good results. (E.G.) [pt

  9. Foreign object detection and removal to improve automated analysis of chest radiographs

    International Nuclear Information System (INIS)

    Hogeweg, Laurens; Sánchez, Clara I.; Melendez, Jaime; Maduskar, Pragnya; Ginneken, Bram van; Story, Alistair; Hayward, Andrew

    2013-01-01

    Purpose: Chest radiographs commonly contain projections of foreign objects, such as buttons, brassier clips, jewellery, or pacemakers and wires. The presence of these structures can substantially affect the output of computer analysis of these images. An automated method is presented to detect, segment, and remove foreign objects from chest radiographs.Methods: Detection is performed using supervised pixel classification with a kNN classifier, resulting in a probability estimate per pixel to belong to a projected foreign object. Segmentation is performed by grouping and post-processing pixels with a probability above a certain threshold. Next, the objects are replaced by texture inpainting.Results: The method is evaluated in experiments on 257 chest radiographs. The detection at pixel level is evaluated with receiver operating characteristic analysis on pixels within the unobscured lung fields and an A z value of 0.949 is achieved. Free response operator characteristic analysis is performed at the object level, and 95.6% of objects are detected with on average 0.25 false positive detections per image. To investigate the effect of removing the detected objects through inpainting, a texture analysis system for tuberculosis detection is applied to images with and without pathology and with and without foreign object removal. Unprocessed, the texture analysis abnormality score of normal images with foreign objects is comparable to those with pathology. After removing foreign objects, the texture score of normal images with and without foreign objects is similar, while abnormal images, whether they contain foreign objects or not, achieve on average higher scores.Conclusions: The authors conclude that removal of foreign objects from chest radiographs is feasible and beneficial for automated image analysis

  10. Radiographic Images Produced by Cosmic-Ray Muons

    International Nuclear Information System (INIS)

    Alfaro, Ruben

    2006-01-01

    An application of high energy physics instrumentation is to look for structure or different densities (materials) hidden in a matrix (tons) of material. By tracing muons produced by primary Cosmic Rays, it has been possible to generate a kind of radiographs which shows the inner structure of dense containers, monuments or mountains. In this paper I review the basics principles of such techniques with emphasis in the Sun Pyramid project, carried out by IFUNAM in collaboration with Instituto Nacioanal de Antropologia e Historia

  11. Radiographers and trainee radiologists reporting accident radiographs

    DEFF Research Database (Denmark)

    Buskov, L; Abild, A; Christensen, A

    2013-01-01

    To compare the diagnostic accuracy and clinical validity of reporting radiographers with that of trainee radiologists whom they have recently joined in reporting emergency room radiographs at Bispebjerg University Hospital....

  12. Radiographic assessment of venous catheter position in children: Value of the lateral view

    International Nuclear Information System (INIS)

    Stark, D.D.; Brasch, R.C.; Gooding, C.A.

    1984-01-01

    Frontal chest radiographs can be misleading in the evaluation of central venous catheter placement. Lateral chest radiographs were obtained, in addition to the standard frontal radiographs, in 25 young children. In five (20%) of the children, the catheters were found to be malpositioned, and the frontal radiograph showed evidence of the abnormality in all five. The lateral radiographs also showed evidence of the abnormality in all five children; however, in three of the five, the lateral radiographs provided additional, more specific, diagnostic information. The lateral chest radiographs also demonstrated satisfactory catheter positioning in three other children in whom the frontal radiographs suggested abnormal positioning. Accurate assessment of catheter position was possible in all patients using both frontal and lateral chest radiographs. Injection of contrast material was not necessary to locate malpositioned catheters. Lateral radiographs are recommended whenever an abnormal catheter position is suspected clinically or from findings on the routine frontal radiograph. (orig.)

  13. A new technique for radiographic measurement of acetabular cup orientation.

    Science.gov (United States)

    Derbyshire, Brian; Diggle, Peter J; Ingham, Christopher J; Macnair, Rory; Wimhurst, James; Jones, Henry Wynn

    2014-02-01

    Accurate radiographic measurement of acetabular cup orientation is required in order to assess susceptibility to impingement, dislocation, and edge loading wear. In this study, the accuracy and precision of a new radiographic cup orientation measurement system were assessed and compared to those of two commercially available systems. Two types of resurfacing hip prostheses and an uncemented prosthesis were assessed. Radiographic images of each prosthesis were created with the cup set at different, known angles of version and inclination in a measurement jig. The new system was the most accurate and precise and could repeatedly measure version and inclination to within a fraction of a degree. In addition it has a facility to distinguish cup retroversion from anteversion on anteroposterior radiographs. © 2013.

  14. Adult Sail Sign: Radiographic and Computed Tomographic Features

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yu-Jin; Han, Daehee; Koh, Young Hwan; Zo, Joo Hee; Kim, Sang-Hyun; Kim, Deog Kyeom; Lee, Jeong Sang; Moon, Hyeon Jong; Kim, Jong Seung; Chun, Eun Ju; Youn, Byung Jae; Lee, Chang Hyun; Kim, Sam Soo (Dept. of Radiology, Cheil General Hospital, Kwandong Univ. College of Medicine, Seoul (KR))

    2008-02-15

    Background: The sail sign is a well-known radiographic feature of the pediatric chest. This sign can be observed in an adult population as well, but for a different reason. Purpose: To investigate the sail sign appearing in adult chest radiography. Material and Methods: Based on two anecdotal adult cases in which frontal chest radiographs showed the sail sign, we prospectively screened radiographs of 10,238 patients to determine the incidence of the sail sign found in adults in their 40s or older. The cause of the sail sign was assessed using computed tomography (CT). Results: The sail sign was revealed in 10 (seven males, three females; median age 60.6 years) of 10,238 patients. Of these 10 patients with a sail sign on frontal radiographs, eight underwent CT. The frontal radiographs of these 10 patients showed a concave superior margin toward the lung in nine patients, a concave inferior margin in five, and a double-lined inferior margin in three. Lateral radiographs disclosed a focal opacity over the minor fissure in five of six patients, which was either fuzzy (n = 4) or sharp (n = 1) in its upper margin, and was sometimes double lined in the inferior margin (n = 3). CT revealed the anterior mediastinal fat to be the cause of the radiographic sail sign, which stretched laterally from the mediastinum to insinuate into the minor fissure. Conclusion: The incidence of sail sign on adult chest radiographs is about 0.1%. The sign is specific enough to eliminate the need for more sophisticated imaging

  15. Adult Sail Sign: Radiographic and Computed Tomographic Features

    International Nuclear Information System (INIS)

    Lee, Yu-Jin; Han, Daehee; Koh, Young Hwan; Zo, Joo Hee; Kim, Sang-Hyun; Kim, Deog Kyeom; Lee, Jeong Sang; Moon, Hyeon Jong; Kim, Jong Seung; Chun, Eun Ju; Y oun, Byung Jae; Lee, Chang Hyun; Kim, Sam Soo

    2008-01-01

    Background: The sail sign is a well-known radiographic feature of the pediatric chest. This sign can be observed in an adult population as well, but for a different reason. Purpose: To investigate the sail sign appearing in adult chest radiography. Material and Methods: Based on two anecdotal adult cases in which frontal chest radiographs showed the sail sign, we prospectively screened radiographs of 10,238 patients to determine the incidence of the sail sign found in adults in their 40s or older. The cause of the sail sign was assessed using computed tomography (CT). Results: The sail sign was revealed in 10 (seven males, three females; median age 60.6 years) of 10,238 patients. Of these 10 patients with a sail sign on frontal radiographs, eight underwent CT. The frontal radiographs of these 10 patients showed a concave superior margin toward the lung in nine patients, a concave inferior margin in five, and a double-lined inferior margin in three. Lateral radiographs disclosed a focal opacity over the minor fissure in five of six patients, which was either fuzzy (n = 4) or sharp (n = 1) in its upper margin, and was sometimes double lined in the inferior margin (n = 3). CT revealed the anterior mediastinal fat to be the cause of the radiographic sail sign, which stretched laterally from the mediastinum to insinuate into the minor fissure. Conclusion: The incidence of sail sign on adult chest radiographs is about 0.1%. The sign is specific enough to eliminate the need for more sophisticated imaging

  16. Adult sail sign: radiographic and computed tomographic features.

    Science.gov (United States)

    Lee, Yu-Jin; Han, Daehee; Koh, Young Hwan; Zo, Joo Hee; Kim, Sang-Hyun; Kim, Deog Kyeom; Lee, Jeong Sang; Moon, Hyeon Jong; Kim, Jong Seung; Chun, Eun Ju; Youn, Byung Jae; Lee, Chang Hyun; Kim, Sam Soo

    2008-02-01

    The sail sign is a well-known radiographic feature of the pediatric chest. This sign can be observed in an adult population as well, but for a different reason. To investigate the sail sign appearing in adult chest radiography. Based on two anecdotal adult cases in which frontal chest radiographs showed the sail sign, we prospectively screened radiographs of 10,238 patients to determine the incidence of the sail sign found in adults in their 40s or older. The cause of the sail sign was assessed using computed tomography (CT). The sail sign was revealed in 10 (seven males, three females; median age 60.6 years) of 10,238 patients. Of these 10 patients with a sail sign on frontal radiographs, eight underwent CT. The frontal radiographs of these 10 patients showed a concave superior margin toward the lung in nine patients, a concave inferior margin in five, and a double-lined inferior margin in three. Lateral radiographs disclosed a focal opacity over the minor fissure in five of six patients, which was either fuzzy (n = 4) or sharp (n = 1) in its upper margin, and was sometimes double lined in the inferior margin (n = 3). CT revealed the anterior mediastinal fat to be the cause of the radiographic sail sign, which stretched laterally from the mediastinum to insinuate into the minor fissure. The incidence of sail sign on adult chest radiographs is about 0.1%. The sign is specific enough to eliminate the need for more sophisticated imaging.

  17. Detection of proximal caries using digital radiographic systems with different resolutions.

    Science.gov (United States)

    Nikneshan, Sima; Abbas, Fatemeh Mashhadi; Sabbagh, Sedigheh

    2015-01-01

    Dental radiography is an important tool for detection of caries and digital radiography is the latest advancement in this regard. Spatial resolution is a characteristic of digital receptors used for describing the quality of images. This study was aimed to compare the diagnostic accuracy of two digital radiographic systems with three different resolutions for detection of noncavitated proximal caries. Diagnostic accuracy. Seventy premolar teeth were mounted in 14 gypsum blocks. Digora; Optime and RVG Access were used for obtaining digital radiographs. Six observers evaluated the proximal surfaces in radiographs for each resolution in order to determine the depth of caries based on a 4-point scale. The teeth were then histologically sectioned, and the results of histologic analysis were considered as the gold standard. Data were entered using SPSS version 18 software and the Kruskal-Wallis test was used for data analysis. P detection of proximal caries (P > 0.05). RVG access system had the highest specificity (87.7%) and Digora; Optime at high resolution had the lowest specificity (84.2%). Furthermore, Digora; Optime had higher sensitivity for detection of caries exceeding outer half of enamel. Judgment of oral radiologists for detection of the depth of caries had higher reliability than that of restorative dentistry specialists. The three resolutions of Digora; Optime and RVG access had similar accuracy in detection of noncavitated proximal caries.

  18. Full-Mouth Intraoral Radiographic Survey in Rabbits.

    Science.gov (United States)

    Regalado, Adriana; Legendre, Loïc

    2017-09-01

    Dental pathologies are highly prevalent in pet rabbit populations, making oral radiography an essential tool in the evaluation of lagomorph dentitions. The unique anatomy of the rabbit's mouth limits the examination of the conscious animal to the rostral portion of it's mouth. In addition, the oral examination of an aradicular hypsodont tooth is restricted to the short coronal fraction of its crown. Erstwhile images obtained by the extraoral technique were once considered the most practical and informative tool in rabbit dentistry; however, limited visualization of the key structures of individual teeth became the major drawback of this technique. As new imaging technologies are becoming widely available and affordable for veterinarians, intraoral radiography offers the ability to prevent, diagnose, and treat oral pathologies in lagomorphs. This article describes a step-by-step procedure to obtain a full-mouth radiographic survey in rabbits. For this technique, a standard dental X-ray generator and intraoral storage phosphor plates are used while applying the bisecting angle technique. Among the advantages of this technique are detailed visualization of internal and external dental structures, identification of early lesions, and detection of occult pathologies. Furthermore, intraoral images offer superior resolution and higher diagnostic quality with minimal radiation exposure, making this method safer for the veterinarian, staff members, and their patients.

  19. The GIK-Archive of sediment core radiographs with documentation

    Science.gov (United States)

    Grobe, Hannes; Winn, Kyaw; Werner, Friedrich; Driemel, Amelie; Schumacher, Stefanie; Sieger, Rainer

    2017-12-01

    The GIK-Archive of radiographs is a collection of X-ray negative and photographic images of sediment cores based on exposures taken since the early 1960s. During four decades of marine geological work at the University of Kiel, Germany, several thousand hours of sampling, careful preparation and X-raying were spent on producing a unique archive of sediment radiographs from several parts of the World Ocean. The archive consists of more than 18 500 exposures on chemical film that were digitized, geo-referenced, supplemented with metadata and archived in the data library PANGAEA®. With this publication, the images have become available open-access for use by the scientific community at https://doi.org/10.1594/PANGAEA.854841.

  20. Radiographic imaging system

    International Nuclear Information System (INIS)

    Davis, L. Jr.; Barrett, H.H.

    1979-01-01

    This invention describes a system for imaging a subject, such as a human being, in which there has been injected a contrast agent which absorbs radiation of a predetermined frequency. The system utilizes a source of high energy radiation such as X or gamma radiation. The source is a composite of first and second radiating materials each of which is arranged in a predetermined pattern or code, each pattern having both luminous and dark regions. In one embodiment, the luminous regions of one pattern are in registration with the dark regions of the other pattern, these regions being spaced apart in an alternative embodiment. The characteristic frequencies of radiation emitted by the first and second materials are respectively lower and higher than the predetermined absorption frequency. A detector of radiation is positioned relative to the subject and the source such that radiation propagating through the subject is incident upon the detector. Since the absorption edge of the contrast agent lies between the two characteristic frequencies of radiation, radiation from the second material is preferentially absorbed by the contrast agent with the result that the contrast agent appears to be illuminated by a coded source while the remainder of the subject may be regarded as illuminated essentially by a uniform uncoded source. Imaging is accomplished by a decoding of a detected coded image. Substances within the subject having other absorption frequencies are not imaged since the radiations of both materials are essentially equally absorbed by the subject so that the source appears uncoded