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Sample records for flat-panel-detector chest radiography

  1. Basic imaging properties of an indirect flat-panel detector system employing irradiation side sampling (ISS) technology for chest radiography: comparison with a computed radiographic system.

    Science.gov (United States)

    Tanaka, Nobukazu; Yano, Yuki; Yabuuchi, Hidetake; Akasaka, Tsutomu; Sasaki, Masayuki; Ohki, Masafumi; Morishita, Junji

    2013-01-01

    The image quality and potential usefulness for patient skin-dose reduction of a newly developed flat-panel detector (FPD) system employing irradiation side sampling (ISS) were investigated and compared to a conventional computed radiography (CR) system. We used the X-ray beam quality of RQA 9 as noted in the standard evaluation method by the International Electrotechnical Commission 62220-1 to evaluate the image quality of the detector for chest radiography. The presampled modulation transfer function (MTF) of the ISS-FPD system was slightly higher than that of the CR system in the horizontal direction at more than 2.2 cycles/mm. However, the presampled MTF of the ISS-FPD system was slightly lower than that of the CR system in the vertical direction. The Wiener spectrum of the ISS-FPD system showed a 50-65 % lesser noise level than that of the CR system under the same exposure condition. The detective quantum efficiency of the ISS-FPD system was at least twice as great as that of the CR system. We conclude that the ISS-FPD system has the potential to reduce the patient skin dose compared to a conventional CR system for chest radiography.

  2. The influence of liquid crystal display monitors on observer performance for the detection of interstitial lung markings on both storage phosphor and flat-panel-detector chest radiography

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    Sung, Yon Mi [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50, Ilwon-dong, Kangnam-ku, Seoul 135-710 (Korea, Republic of); Department of Radiology, Gachon University Gil Hospital, 1198, Guwol-dong, Namdong-gu, Incheon 405-760 (Korea, Republic of); Chung, Myung Jin [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50, Ilwon-dong, Kangnam-ku, Seoul 135-710 (Korea, Republic of)], E-mail: mj1.chung@samsung.com; Lee, Kyung Soo [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50, Ilwon-dong, Kangnam-ku, Seoul 135-710 (Korea, Republic of); Choe, Bong-Keun [Department of Preventive Medicine, School of Medicine, Kyunghee University, Seoul (Korea, Republic of)

    2010-04-15

    Purpose: To compare observer performance with a flat-panel liquid crystal display (LCD) monitor and with a high-resolution gray-scale cathode ray tube (CRT) monitor in the detection of interstitial lung markings using a silicon flat-panel-detector direct radiography (DR) and storage phosphor computed radiography (CR) in a clinical setting. Materials and methods: We displayed 39 sets of posteroanterior chest radiographs from the patients who were suspected of interstitial lung disease. Each sets consisted of DR, CR and thin-section CT as the reference standard. Image identities were masked, randomly sorted, and displayed on both five mega pixel (2048 x 2560 x 8 bits) LCD and CRT monitors. Ten radiologists independently rated their confidence in detection for the presence of linear opacities in the four fields of the lungs; right upper, left upper, right lower, and left lower quadrant. Performance of a total 6240 (39 sets x 2 detector systems x 2 monitor system x 4 fields x 10 observers) observations was analyzed by multi-reader multi-case receiver operating characteristic (ROC) analysis. Differences between monitor systems in combinations of detector systems were compared using ANOVA and paired-samples t-test. Results: Area under curves (AUC) for the presence of linear opacities measured by ROC analysis was higher on the LCDs than CRTs without statistical significance (p = 0.082). AUC was significantly higher on the DR systems than CR systems (p = 0.006). AUC was significantly higher on the LCDs than CRTs for DR systems (p = 0.039) but not different for CR systems (p = 0.301). Conclusion: In clinical conditions, performance of the LCD monitor appears to be better for detecting interstitial lung markings when interfaced with DR systems.

  3. Development of patient collation system by kinetic analysis for chest dynamic radiogram with flat panel detector

    Science.gov (United States)

    Tsuchiya, Yuichiro; Kodera, Yoshie

    2006-03-01

    In the picture archiving and communication system (PACS) environment, it is important that all images be stored in the correct location. However, if information such as the patient's name or identification number has been entered incorrectly, it is difficult to notice the error. The present study was performed to develop a system of patient collation automatically for dynamic radiogram examination by a kinetic analysis, and to evaluate the performance of the system. Dynamic chest radiographs during respiration were obtained by using a modified flat panel detector system. Our computer algorithm developed in this study was consisted of two main procedures, kinetic map imaging processing, and collation processing. Kinetic map processing is a new algorithm to visualize a movement for dynamic radiography; direction classification of optical flows and intensity-density transformation technique was performed. Collation processing consisted of analysis with an artificial neural network (ANN) and discrimination for Mahalanobis' generalized distance, those procedures were performed to evaluate a similarity of combination for the same person. Finally, we investigated the performance of our system using eight healthy volunteers' radiographs. The performance was shown as a sensitivity and specificity. The sensitivity and specificity for our system were shown 100% and 100%, respectively. This result indicated that our system has excellent performance for recognition of a patient. Our system will be useful in PACS management for dynamic chest radiography.

  4. Data pre-processing for quantification in tomography and radiography with a digital flat panel detector

    Science.gov (United States)

    Rinkel, Jean; Gerfault, Laurent; Estève, François; Dinten, Jean-Marc

    2006-03-01

    In order to obtain accurate quantitative results, flat panel detectors require specific calibration and correction of acquisitions. Main artefacts are due to bad pixels, variations of photodiodes characteristics and inhomogeneity of X-rays sensitivity of the scintillator layer. Other limitations for quantification are the non-linearity of the detector due to charge trapping in the transistors and the scattering generated inside the detector, called detector scattering. Based on physical models of artefacts generation, this paper presents an unified framework for the calibration and correction of these artefacts. The following specific algorithms have been developed to correct them. A new method for correction of deviation to linearity is based on the comparison between experimental and simulated data. A method of detector scattering correction is performed in two steps: off-line characterization of detector scattering by considering its spatial distribution through a convolution model and on-line correction based on a deconvolution approach. Radiographic results on an anthropomorphic thorax phantom imaged with a flat panel detector, that convert X-rays into visible light using scintillator coupled to an amorphous silicon transistor frame for photons to electrons conversion, demonstrate that experimental X-rays attenuation images are significantly improved qualitatively and quantitatively by applying non-linearity correction and detector scattering correction. Results obtained on tomographic reconstructions from pre-processed acquisitions of the phantom are in very good agreement with expected attenuation coefficients values obtained with a multi-slice CT scanner. Thus, this paper demonstrates the efficiency of the proposed pre-processings to perform accurate quantification on radiographies and tomographies.

  5. Dual-Energy Subtraction Imaging for Diagnosing Vocal Cord Paralysis with Flat Panel Detector Radiography

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    Machida, Haruhiko; Yoda, Keiko; Arai, Yasuko [Tokyo Women' s Medical University Medical Center East, Tokyo (Japan)] (and others)

    2010-06-15

    To investigate the clinical feasibility of dual energy subtraction (DES) imaging to improve the delineation of the vocal cord and diagnostic accuracy of vocal cord paralysis as compared with the anterior-posterior view of flat panel detector (FPD) neck radiography. For 122 consecutive patients who underwent both a flexible laryngoscopy and conventional/DES FPD radiography, three blinded readers retrospectively graded the radiographs during phonation and inspiration on a scale of 1 (poor) to 5 (excellent) for the delineation of the vocal cord, and in consensus, reviewed the diagnostic accuracy of vocal cord paralysis employing the laryngoscopy as the reference. We compared vocal cord delineation scores and accuracy of vocal cord paralysis diagnosis by both conventional and DES techniques using ({kappa}statistics and assessing the area under the receiver operating characteristic curve (AUC). Vocal cord delineation scores by DES (mean, 4.2 {+-} 0.4) were significantly higher than those by conventional imaging (mean, 3.3 {+-} 0.5) (p < 0.0001). Sensitivity for diagnosing vocal cord paralysis by the conventional technique was 25%, whereas the specificity was 94%. Sensitivity by DES was 75%, whereas the specificity was 96%. The diagnostic accuracy by DES was significantly superior (({kappa}= 0.60, AUC = 0.909) to that by conventional technique ({kappa}= 0.18, AUC = 0.852) (p = 0.038). Dual energy subtraction is a superior method compared to the conventional FPD radiography for delineating the vocal cord and accurately diagnosing vocal cord paralysis.

  6. MTF compensation for digital radiography system with indirect conversion flat panel detector

    Science.gov (United States)

    Zhang, Wei; Souchay, Henri; Yang, Chao

    2009-02-01

    The MTF (modulation transfer function) of digital radiography systems can be enhanced in the spatial frequency domain due to their high signal to noise ratio. A Wiener filter, which requires prior estimation of the noise and signal power spectrum of the images, was used to compensate MTF of the detector and thereby optimally restore the images details. We studied the noise characteristics of two flat panel detectors with structured columnar scintillator (CsI) and granular scintillator (Gd2O2S). A noise model formulating noise transfer process was applied to estimate the noise components for the filter. Signal model was based on dose of the application. We revisited the noise and signal model that was used in previous work by Souchay et al. for mammography application [1], considering the difference in detector characteristics and the applications (extremity x-ray) that we are specifically investigating. Starting with real clinical images, we used an observer study method to measure the visually optimal parameter for the Wiener filter. A set of clinical images was used to evaluate the radiologists' preferences to compensated images against the reference images. Statistical results from three experienced radiologists ranking results show that the compensated images are preferred over the reference images.

  7. Development and evaluation of a digital radiography system using a large-area flat-panel detector

    Science.gov (United States)

    Suzuki, Katsumi; Ikeda, Shigeyuki; Ishikawa, Ken; Iinuma, Gen; Ogasawara, Satoshi; Moriyama, Noriyuki; Konno, Yasutaka

    2002-05-01

    A new DR system using a large-area flat panel detector (FPD) with a 40 by 30 cm active area and a 194 micrometers pixel pitch, has been developed to compare with a conventional image intensifier and charge-coupled device camera type DR system. After measuring basic characteristics of the new DR system such as signal-to-noise ratio, modulation transfer function, and detective quantum efficiency, we applied the FPD to a Gastro-Intestinal study with contrast media, and discussed its potential for clinical use with a medical doctor. In radiography mode, the new DR system with a large-are FPD has superior image quality compared with the conventional I.I.- CCD camera type DR system because of high SNR and DQE. In fluoroscopy mode, the SNR of the new DR system at the exposure range of over 2(mu) R/frame is similar with the conventional I.I.-CCD camera type DR system. As a result, we considered that new DR system with a large-area FPD could be applied to a clinical study replacing an I.I.-CCD camera type. In the evaluation using various clinical images taken with the new DR system by a medical doctor, the new DR system with a large-are FPD performed sufficiently for a GI study.

  8. Development of CT and 3D-CT Using Flat Panel Detector Based Real-Time Digital Radiography System

    Science.gov (United States)

    Ravindran, V. R.; Sreelakshmi, C.; Vibin, Vibin

    2008-09-01

    The application of Digital Radiography in the Nondestructive Evaluation (NDE) of space vehicle components is a recent development in India. A Real-time DR system based on amorphous silicon Flat Panel Detector has been developed for the NDE of solid rocket motors at Rocket Propellant Plant of VSSC in a few years back. The technique has been successfully established for the nondestructive evaluation of solid rocket motors. The DR images recorded for a few solid rocket specimens are presented in the paper. The Real-time DR system is capable of generating sufficient digital X-ray image data with object rotation for the CT image reconstruction. In this paper the indigenous development of CT imaging based on the Realtime DR system for solid rocket motor is presented. Studies are also carried out to generate 3D-CT image from a set of adjacent CT images of the rocket motor. The capability of revealing the spatial location and characterisation of defect is demonstrated by the CT and 3D-CT images generated.

  9. [Flat-panel detectors in X-ray systems].

    Science.gov (United States)

    Spahn, M; Heer, V; Freytag, R

    2003-05-01

    For all application segments X-ray systems with flat-panel detectors increasingly enter the market. In digital radiography,mammography and cardiologic angiography flat-panel detectors are already well established while they are made ready for market introduction in general angiography and fluoroscopy. Two flat-panel detector technologies are available. One technology is based on an indirect conversion process of X-rays while the other one uses a direct conversion method. For radiography and dynamic applications the indirect method provides substantial advantages, while the direct method has some benefits for mammography. In radiography and mammography flat-panel detectors lead to clear improvements with respect to workflow, image quality and dose reduction potentials. These improvements are fostered by the immediate availability of the image, the large dynamic range and the high sensitivity to X-rays. New applications and the use of complex image processing algorithms have the potential to enlarge the present diagnostic range of applications. Up to now, image intensifiers are still the well-established technology for angiography and fluoroscopy. Nevertheless flat-panel detectors begin to enter this field, especially in cardiologic angiography. Characteristics of flat-panel detectors such as the availability of distortion-free images, the excellent contrast resolution, the large dynamic range, the high sensitivity to X-rays and the usability in magnetic fields provide the basis for improved and new diagnostic and interventional methods.

  10. Radiation dose reduction in scoliosis patients. Low-dose full-spine radiography with digital flat panel detector and image stitching system

    Energy Technology Data Exchange (ETDEWEB)

    Grieser, T. [Klinikum Augsburg (Germany). Klinik fuer Diagnostische Radiologie und Neuroradiologie; Baldauf, A.Q. [Theresienkrankenhaus Mannheim (Germany). Abt. fuer Radiologie; Ludwig, K. [Klinikum Herford (Germany). Klinik fuer Diagnostische und Interventionelle Radiologie

    2011-07-15

    Purpose: To evaluate the exposure dose reduction with a digital flat panel detector (FPD) and an image stitching system (ISS) in full-spine radiography for scoliosis patients. Materials and Methods: During a 6-month period, all consecutive scoliosis patients with a clinical indication for full-spine radiography (n = 50) were examined with an FPD and ISS. Automatic exposure control adjusted to speed class 1600 was used together with age-adjusted tube voltage and filtration. Dose area products were recorded for all images (antero-posterior n = 50, lateral n = 18). Images were evaluated by two radiologists for the possibility (possible, impossible) of typical scoliosis measurements (Cobb angle, Stagnara angle, lateral deviation, Risser stage). All measurements assessed as impossible underwent a second evaluation categorizing the reason why a measurement was impossible (underlying pathology, projection, image quality). Patient characteristics influencing exposure were recorded (sex, age, weight, height). Mean dose area products were compared to the literature with consideration of patient group and image quality. Results: The mean dose area product was 16.8 {mu}Gy m{sup 2} for antero-posterior images and 26.6 {mu}Gy m{sup 2} for lateral images. A comparison to published values showed an exposure dose reduction of 47 % to 93 %. Measurement of the Cobb and Stagnara angle, lateral deviation and Risser stage was possible in 96 % (n = 50), 83 % (n = 18), 100 % (n = 50) and 100 % (n = 50) of cases. The reasons for impossible measurements were independent of image quality (underlying pathologies, projection). Conclusion: When imaging scoliosis patients, an FPD combined with an ISS can substantially reduce the exposure dose. (orig.)

  11. Performance of a flat-panel detector in the detection of artificial erosive changes: comparison with conventional screen-film and storage-phosphor radiography

    Energy Technology Data Exchange (ETDEWEB)

    Ludwig, Karl; Henschel, Andreas; Bernhardt, Thomas M.; Lenzen, Horst; Wormanns, Dag; Diederich, Stefan; Heindel, Walter [Department of Clinical Radiology, University of Muenster, Albert-Schweitzer-Strasse 33, 48129, Muenster (Germany)

    2003-06-01

    Heading Abstract.The purpose of this study was to compare a large-area, direct-readout, flat-panel detector system with a conventional screen-film system, a storage-phosphor system, and a mammography screen-film system with regard to the detection of artificial bone erosions simulating rheumatoid disease, and to assess its diagnostic performance with decreasing exposure dose. Six hundred forty regions were defined in 160 metacarpophalangeal and proximal interphalangeal joint specimens from 20 monkey paws (4 regions per joint). Artificial bone erosions were created in 320 of these 640 regions. Specimens were enclosed in containers filled with water to obtain absorption and scatter radiation conditions similar to those of a human hand. Imaging was performed using a flat-panel system, a speed class 200 screen-film system, a mammography screen-film system, and a storage-phosphor system under exactly matched conditions. Different exposure doses equivalent to speed classes of S=100, 200, 400, 800, 1600, and 3200 were used. In all images the presence or absence of a lesion was assessed by three radiologists using a five-level confidence scale. Receiver operating characteristic (ROC) analysis was performed for a total of 21,120 observations (1920 for each imaging modality and exposure level) and diagnostic performance estimated by the area under the ROC curve (A{sub z}). The significance of differences in diagnostic performance was tested with analysis of variance. The ROC analysis showed A{sub z} values of 0.809 (S=200), 0.768 (S=400), 0.737 (S=800), 0.710 (S=1600), and 0.685 (S=3200) for the flat-panel system, 0.770 for the speed class 200 screen-film system, 0.781 (S=200), 0.739 (S=400), 0.724 (S=800), 0.680 (S=1600) for the storage-phosphor system, and 0.798 for the mammography screen-film system. Analysis of variance showed significant differences between different combinations of imaging modalities and exposure doses (p <0.05). The diagnostic performance of the flat-panel

  12. [Present state and future of flat panel detector in Japan].

    Science.gov (United States)

    Higashida, Yoshiharu

    2002-01-01

    In our country, the introduction of flat panel detector is carried out in the diagnosis region since before several years. In flat panel detector with the high image characteristic, large expectation is being placed. In this paper, image characteristic of flat panel detector and effectiveness of clinical application were reviewed. It is anticipated that flat panel detector with the excellent image characteristic gives large effect in the radiological diagnosis.

  13. Resolution requirements for monitor viewing of digital flat-panel detector radiographs: a contrast detail analysis

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    Peer, Siegfried; Giacomuzzi, Salvatore M.; Peer, Regina; Gassner, Eva; Steingruber, Iris; Jaschke, Werner [Department of Radiology, University Hospital, Anichstrasse 35, 6020 Innsbruck (Austria)

    2003-02-01

    With the introduction of digital flat-panel detector systems into clinical practice, the still unresolved question of resolution requirements for picture archiving communication system (PACS) workstation monitors has gained new momentum. This contrast detail analysis was thus performed to define the differences in observer performance in the detection of small low-contrast objects on clinical 1K and 2K monitor workstations. Images of the CDRAD 2.0 phantom were acquired at varying exposures on an indirect-type digital flat-panel detector. Three observers evaluated a total of 15 images each with respect to the threshold contrast for each detail size. The numbers of correctly identified objects were determined for all image subsets. No significant difference in the correct detection ratio was detected among the observers; however, the difference between the two types of workstations (1K vs 2K monitors) despite less than 3% was significant at a 95% confidence level. Slight but statistically significant differences exist in the detection of low-contrast nodular details visualized on 1K- and 2K-monitor workstations. Further work is needed to see if this result holds true also for comparison of clinical flat-panel detector images and may, for example, exert an influence on the diagnostic accuracy of chest X-ray readings. (orig.)

  14. Digital chest radiography

    DEFF Research Database (Denmark)

    Debess, Jeanne Elisabeth; Johnsen, Karen Kirstine; Thomsen, Henrik

    2015-01-01

    Background: Chest radiography is one of the most common examinations in radiology departments. In 2013 approximately 80,000 chest x-rays were performed on women in the fertile age. Even low dose for the examinationCorrect collimation Purpose: Quality improvement of basic radiography focusing...... collimations depending on side of radiograph. Results from dose reduction will be presented on the congress Conclusion: Correct positioning and collimation of digital chest radiographs can reduce the radiation dose significant to the patients and by that improve the quality of basic radiography....... on collimation and dose reduction in digital chest radiography Methods and Materials A retrospective study of digital chest radiography is performed to evaluate the primary x-ray tube collimation of the PA and lateral radiographs. Data from one hundred fifty self-reliant female patients between 15 and 55 years...

  15. Comparison of low-contrast detail perception on storage phosphor radiographs and digital flat panel detector images.

    Science.gov (United States)

    Peer, S; Neitzel, U; Giacomuzzi, S M; Peer, R; Gassner, E; Steingruber, I; Jaschke, W

    2001-03-01

    A contrast detail analysis was performed to compare perception of low-contrast details on X-ray images derived from digital storage phosphor radiography and from a flat panel detector system based on a cesium iodide/amorphous silicon matrix. The CDRAD 2.0 phantom was used to perform a comparative contrast detail analysis of a clinical storage phosphor radiography system and an indirect type digital flat panel detector unit. Images were acquired at exposure levels comparable to film speeds of 50/100/200/400 and 800. Four observers evaluated a total of 50 films with respect to the threshold contrast for each detail size. The numbers of correctly identified objects were determined for all image subsets. The overall results show that low-contrast detail perception with digital flat panel detector images is better than with state of the art storage phosphor screens. This is especially true for the low-exposure setting, where a nearly 10% higher correct observation ratio is reached. Given its high detective quantum efficiency the digital flat panel technology based on the cesium iodide scintillator/amorphous silicon matrix is best suited for detection of low-contrast detail structures, which shows its high potential for clinical imaging.

  16. Digital chest radiography

    DEFF Research Database (Denmark)

    Debess, Jeanne Elisabeth; Vejle-Sørensen, Jens Kristian; Thomsen, Henrik;

    2015-01-01

    of clinical supervisors. Optimal collimation is determined by European and Regional Danish guidelines. The areal between current and optimal collimation is calculated. The experimental research is performed in September - October 2014 Siemens Axiom Aristos digital radiography system DR using 150 kV, 1,25 -3......Purpose: Quality improvement of basic radiography focusing on collimation and dose reduction in digital chest radiography Methods and Materials:A retrospective study of digital chest radiography is performed to evaluate the primary x-ray tube collimation of the PA and lateral radiographs. Data from...... one hundred fifty self-reliant female patients between 15 and 55 years of age are included in the study. The clinical research is performed between September and November 2014 where 3rd year Radiography students collect data on four Danish x-ray departments using identical procedures under guidance...

  17. Optimized anti-scatter grids for flat panel detectors

    Science.gov (United States)

    Lendl, Markus

    2007-03-01

    Anti-scatter grids are well established in the field of X-ray projection imaging. In general these grids consist of a large number of parallel lead lamellae separated by X-ray-transparent material. This regular structure defines the characteristic grid frequency. Modern X-ray imaging systems apply digital receptors, i.e. image intensifiers coupled to a CCD camera or solid state flat-panel detector. Combining a digital detector and an anti-scatter grid may lead to Moire artifacts. This results from sampling an analog X-ray image with signal components higher than half the sampling frequency. Especially in high dose DSA images (Digital Subtraction Angiography) these irritating artifacts may be visible to the user. In this paper we present a concept for minimizing these grid artifacts: Signal propagation in the detector is modeled by three steps, scintillator MTF, aperture MTF, and sampling. Since the scintillator MTF is irrelevant for the grid optimization process, we focus on aperture MTF and sampling. From the given geometry of the detector elements the corresponding 2D Fourier transform is calculated. An evaluation for typical grid frequencies, i.e. arcs around the origin of the 2D Fourier transform, results in profiles exhibiting pronounced minima. From the respective angle values for these minima, grid orientation can be optimized for minimum Moire disturbances. Simulation results for typical detector pixel geometries and for grid frequencies used in practice are validated by measurement for two different anti-scatter grids on a Siemens angiographic system with a digital flat-panel detector.

  18. Unfolding X-ray spectra using a flat panel detector.

    Science.gov (United States)

    Gallardo, Sergio; Juste, Belén; Pozuelo, Fausto; Ródenas, José; Querol, Andrea; Verdú, Gumersindo

    2013-01-01

    It is difficult to measure the energy spectrum of X-ray tubes due to the pile up effect produced by the high fluence of photons. Using attenuating materials, appropriate detector devices and the Monte Carlo method, primary X-ray spectrum of these devices can be estimated. In this work, a flat panel detector with a PMMA wedge has been used to obtain a dose curve corresponding to certain working conditions of a radiodiagnostic X-ray tube. The relation between the dose curve recorded by the flat panel and the primary X-ray spectrum is defined by a response function. Normally this function can be approximated by a matrix, which can be obtained by means of the Monte Carlo method. Knowing the measured dose curve and the response matrix, the primary X-ray spectrum can be unfolded. However, there are some problems that strongly affect the applicability of this method: i.e. technical features of the flat panel and inherent characteristics of the involved radiation physics (ill-posed problem). Both aspects are analyzed in this work, concluding that the proposed method can be applied with an acceptable accuracy for spectra without characteristic lines, for instance, tungsten anode in the 50-70 kVp range.

  19. Focal spot measurements using a digital flat panel detector

    Science.gov (United States)

    Jain, Amit; Panse, A.; Bednarek, Daniel R.; Rudin, Stephen

    2014-03-01

    Focal spot size is one of the crucial factors that affect the image quality of any x-ray imaging system. It is, therefore, important to measure the focal spot size accurately. In the past, pinhole and slit measurements of x-ray focal spots were obtained using direct exposure film. At present, digital detectors are replacing film in medical imaging so that, although focal spot measurements can be made quickly with such detectors, one must be careful to account for the generally poorer spatial resolution of the detector and the limited usable magnification. For this study, the focal spots of a diagnostic x-ray tube were measured with a 10-μm pinhole using a 194-μm pixel flat panel detector (FPD). The twodimensional MTF, measured with the Noise Response (NR) Method was used for the correction for the detector blurring. The resulting focal spot sizes based on the FWTM (Full Width at Tenth Maxima) were compared with those obtained with a very high resolution detector with 8-μm pixels. This study demonstrates the possible effect of detector blurring on the focal spot size measurements with digital detectors with poor resolution and the improvement obtained by deconvolution. Additionally, using the NR method for measuring the two-dimensional MTF, any non-isotropies in detector resolution can be accurately corrected for, enabling routine measurement of non-isotropic x-ray focal spots. This work presents a simple, accurate and quick quality assurance procedure for measurements of both digital detector properties and x-ray focal spot size and distribution in modern x-ray imaging systems.

  20. Digital radiography of the chest in pediatric patients; Die digitale Thoraxradiographie beim paediatrischen Patienten

    Energy Technology Data Exchange (ETDEWEB)

    Puig, S. [Universitaetsklinik fuer Radiodiagnostik, Wien (Austria)

    2003-12-01

    The hopes placed in digital radiography have been fulfilled only partly in pediatric radiology. Specifically, the option of gaining reduced radiation exposure in combination with a similar or even improved image quality was hard to realize. The only portable digital system available for a long time were storage phosphors which were disadvantaged by an extremely limited dose-quantum-efficiency (DQE) in comparison to digital flat panel detectors. New developments and the introduction of the dual-reading system led to image qualities comparable to film-screen-systems with high resolution and achievable without dose increase, sometimes even with dose reduction. A study using an animal model suggests that these systems can even be used in preterm infants with very low birth weights. A new portable flat panel detector by Canon may improve digital chest radiography in pediatric patients. (orig.) [German] Erwartungen, die man anfaenglich in die digitale Projektionsradiographie gesetzt hat, haben sich in der Kinderradiologie erst verzoegert oder teilweise gar nicht erfuellt. Insbesondere Hoffnungen, dass man die Strahlenbelastung bei gleich bleibender oder gar verbesserter Bildqualitaet reduzieren koennte, wurden bald enttaeuscht. Das einzige portable digitale System waren lange Zeit Phosphorplatten, die aber im Vergleich zu den Festplattendetektoren eine aeusserst limitierte Dosisquanteneffizienz (DQE) hatten. Durch neue Entwicklungen und v. a. durch die Einfuehrung des Dual-reading-Systems kann eine Bildqualitaet erreicht werden, die an hochaufloesende Film-Folien-Systeme heranreicht, ohne die Dosis erhoehen zu muessen. Teilweise ist nun auch eine Dosisreduktion moeglich. In einem Tiermodell konnte gezeigt werden, dass diese Systeme auch bei Fruehgeborenen mit einem sehr niedrigen Geburtgewicht einsetzbar sind. Hoffnung wird in ein neues portables Festplattendetektorsystem gesetzt, welches in der paediatrischen digitalen Thoraxradiographie evtl. neue Massstaebe setzen

  1. [Flat-panel detector technology -State-of-the-art and future prospects-].

    Science.gov (United States)

    Yamazaki, Tatsuya

    2002-01-01

    A flat-panel detector (FPD) is a long-awaited technology to implement the digital X-ray imaging technology into the radiological department. This paper describes the state-of-the-art technology and future prospects on the FPD technology. State-of-the-art technology was reviewed taking the CXDI series as an example. Several FPD-based systems have been introduced into the Japanese market since CXDI-11 opened it in November 1998. Accompanying CXDI-C2 for control, CXDI-22 for table position and CXDI-31 for portable, the CXDI series fulfills the requirement of the radiography room being a fully digitalized room. The FPD on the CXDI series is comprised of a scintillator (Gd(2)O(2)S:Tb(3+)) as a primary sensor in which the X-ray is captured and an amorphous silicon detector (LANMIT) as a secondary sensor in which the fluorescent light is detected. Since the scintillator is identical to that of the screen-film systems, it can be said as proven, durable and chemically stable and it is expected to produce the same image quality as the screen-film systems. CXDI-31, a portable FPD-based system, was developed targeting thinner dimensions, lightweight, durability and high spatial resolution. Thoroughly re-designing the mechanical structure and reducing the power consumption at the readout IC realized thinner dimensions. Introducing the portable note PC technologies successfully combined lightweight with durability. Improving the sensor process and re-designing the layout made the sensor high resolution without compromising the signal-to-noise ratio. Future prospects were overviewed in the aspect of technology and applications. Sensitivity, spatial resolution, frame rate and portability were described as the upcoming technology. Increasing gain and reducing noise will realize higher sensitivity, especially by adopting the PbI(2), HgI(2) or such photoconductor materials as the primary sensor. Pixelized amplifier will also achieve higher sensitivity. Layered sensor designed such

  2. Amorphous selenium flat panel detectors for medical applications

    Science.gov (United States)

    Zhao, Wei; Hunt, D. C.; Tanioka, Kenkichi; Rowlands, J. A.

    2005-09-01

    Different technologies for making X-ray sensitive active matrix flat-panel imagers (AMFPI) are reviewed for applications in digital radiography and fluoroscopy. Aspects of imaging performance requiring improvement are identified and potential new detector concepts addressing these issues are briefly described. The rationale is given for the investigation of a new detector concept—an indirect conversion FPI with avalanche gain—for low-dose X-ray imaging. This detector consists of an amorphous selenium (a-Se) photoconductor optically coupled to a structured cesium iodide (CsI) scintillator. Under an electric field ESe, the a-Se is sensitive to light and converts the optical photons emitted from CsI into electronic signal that can be stored and read out in the same fashion as in existing AMFPI. When ESe is increased to >90 V/μm, avalanche multiplication occurs. The avalanche gain ranges between 1-800 depending on ESe and the thickness of the a-Se layer. The avalanche a-Se photoconductor is referred to as High-gain Avalanche Rushing amorphous Photoconductor. The feasibility of two detector configurations based on avalanche gain, each using a different image readout method, are under investigation. Their advantages are compared to other AMPFI technologies for digital radiography and fluoroscopy.

  3. Imaging responses of on-site CsI and Gd2O2S flat-panel detectors: Dependence on the tube voltage

    Science.gov (United States)

    Jeon, Hosang; Chung, Myung Jin; Youn, Seungman; Nam, Jiho; Lee, Jayoung; Park, Dahl; Kim, Wontaek; Ki, Yongkan; Kim, Ho Kyung

    2015-07-01

    One of the emerging issues in radiography is low-dose imaging to minimize patient's exposure. The scintillating materials employed in most indirect flat-panel detectors show a drastic change of X-ray photon absorption efficiency around their K-edge energies that consequently affects image quality. Using various tube voltages, we investigated the imaging performance of most popular scintillators: cesium iodide (CsI) and gadolinium oxysulfide (Gd2O2S). The integrated detective quantum efficiencies (iDQE) of four detectors installed in the same hospital were evaluated according to the standardized procedure IEC 62220-1 at tube voltages of 40 - 120 kVp. The iDQE values of the Gd2O2S detectors were normalized by those of CsI detectors to exclude the effects of image postprocessing. The contrast-to-noise ratios (CNR) were also evaluated by using an anthropomorphic chest phantom. The iDQE of the CsI detector outperformed that of the Gd2O2S detector over all tube voltages. Moreover, we noted that the iDQE of the Gd2O2S detectors quickly rolled off with decreasing tube voltage under 70 kVp. The CNRs of the two scintillators were similar at 120 kVp. At 60 kVp, however, the CNR of Gd2O2S was about half that of CsI. Compared to the Gd2O2S detectors, variations in the DQE performance of the CsI detectors were relatively immune to variations in the applied tube voltages. Therefore, we claim that Gd2O2S detectors are inappropriate for use in low-tube-voltage imaging (e.g., extremities and pediatrics) with low patient exposure.

  4. Characterization and application of a GE amorphous silicon flat panel detector in a synchrotron light source

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J.H. [XSD Advanced Photon Source, Argonne National Laboratory (United States)], E-mail: jlee@aps.anl.gov; Almer, J. [XSD Advanced Photon Source, Argonne National Laboratory (United States); Aydiner, C. [Los Alamos National Laboratory (United States); Bernier, J.; Chapman, K.; Chupas, P.; Haeffner, D. [XSD Advanced Photon Source, Argonne National Laboratory (United States); Kump, K. [GE Healthcare (United States); Lee, P.L.; Lienert, U.; Miceli, A. [XSD Advanced Photon Source, Argonne National Laboratory (United States); Vera, G. [GE Healthcare (United States)

    2007-11-11

    Characterization, in the language of synchrotron radiation, was performed on a GE Revolution 41RT flat panel detector using the X-ray light source at the Advanced Photon Source (APS). The detector has an active area of 41x41 cm{sup 2} with 200x200 {mu}m{sup 2} pixel size. The nominal working photon energy is around 80 keV. Modulation transfer function (MTF) was measured in terms of line spread function (LSF) using a 25 {mu}mx1 cm tungsten slit. Memory effects of the detector elements, called lag, were also measured. The large area and fast data capturing rate -8 fps in unbinned mode, 30 fps in binned or region of interest (ROI) mode-make the GE flat panel detector a unique and very versatile detector for synchrotron experiments. In particular, we present data from pair distribution function (PDF) measurements to demonstrate the special features of this detector.

  5. Comparison of ring artifact removal methods using flat panel detector based CT images

    OpenAIRE

    2011-01-01

    Abstract Background Ring artifacts are the concentric rings superimposed on the tomographic images often caused by the defective and insufficient calibrated detector elements as well as by the damaged scintillator crystals of the flat panel detector. It may be also generated by objects attenuating X-rays very differently in different projection direction. Ring artifact reduction techniques so far reported in the literature can be broadly classified into two groups. One category of the approac...

  6. Photodiode forward bias to reduce temporal effects in a-Si based flat panel detectors

    Science.gov (United States)

    Mollov, Ivan; Tognina, Carlo; Colbeth, Richard

    2008-03-01

    Lag and sensitivity modulation are well known temporal artifacts of a-Si photodiode based flat panel detectors. Both effects are caused by charge carriers being trapped in the semiconductor. Trapping and releasing of these carriers is a statistical process with time constants much longer than the frame time of flat panel detectors. One way to reduce these temporal artifacts is to keep the traps filled by applying a pulse of light over the entire detector area every frame before the x-ray exposure. This paper describes an alternative method, forward biasing the a-Si photodiodes and supplying free carriers to fill the traps. The array photodiodes are forward biased and then reversed biased again every frame between the panel readout and x-ray exposure. The method requires no change to the mechanical construction of the detector, only minor modifications of the detector electronics and no image post processing. An existing flat panel detector was modified and evaluated for lag and sensitivity modulation. The required changes of the panel configuration, readout scheme and readout timing are presented in this paper. The results of applying the new technique are presented and compared to the standard mode of operation. The improvements are better than an order of magnitude for both sensitivity modulation and lag; lowering their values to levels comparable to the scintillator afterglow. To differentiate the contribution of the a-Si array, from that of the scintillator, a large area light source was used. Possible implementations and applications of the method are discussed.

  7. Dual-exposure technique for extending the dynamic range of x-ray flat panel detectors.

    Science.gov (United States)

    Sisniega, A; Abella, M; Desco, M; Vaquero, J J

    2014-01-20

    This work presents an approach to extend the dynamic range of x-ray flat panel detectors by combining two acquisitions of the same sample taken with two different x-ray photon flux levels and the same beam spectral configuration. In order to combine both datasets, the response of detector pixels was modelled in terms of mean and variance using a linear model. The model was extended to take into account the effect of pixel saturation. We estimated a joint probability density function (j-pdf) of the pixel values by assuming that each dataset follows an independent Gaussian distribution. This j-pdf was used for estimating the final pixel value of the high-dynamic-range dataset using a maximum likelihood method. The suitability of the pixel model for the representation of the detector signal was assessed using experimental data from a small-animal cone-beam micro-CT scanner equipped with a flat panel detector. The potential extension in dynamic range offered by our method was investigated for generic flat panel detectors using analytical expressions and simulations. The performance of the proposed dual-exposure approach in realistic imaging environments was compared with that of a regular single-exposure technique using experimental data from two different phantoms. Image quality was assessed in terms of signal-to-noise ratio, contrast, and analysis of profiles drawn on the images. The dynamic range, measured as the ratio between the exposure for saturation and the exposure equivalent to instrumentation noise, was increased from 76.9 to 166.7 when using our method. Dual-exposure results showed higher contrast-to-noise ratio and contrast resolution than the single-exposure acquisitions for the same x-ray dose. In addition, image artifacts were reduced in the combined dataset. This technique to extend the dynamic range of the detector without increasing the dose is particularly suited to image samples that contain both low and high attenuation regions.

  8. Evaluation of stent visibility by flat panel detector CT in patients treated for intracranial aneurysms

    Energy Technology Data Exchange (ETDEWEB)

    Clarencon, Frederic [Groupe Hospitalier Pitie-Salpetriere, Paris (France); Pitie-Salpetriere Hospital, Department of Neuroradiology, Paris (France); Piotin, Michel; Pistocchi, Silvia; Blanc, Raphael [Fondation A. de Rothschild, Paris (France); Babic, Drazenko [Philips Healthcare, Best (Netherlands)

    2012-10-15

    This study aimed to evaluate the visibility of stents using high-resolution computed tomography (CT) acquisitions acquired with flat panel detector (XperCT, Allura series, Philips Healthcare, The Netherlands) for endovascular treatment of intracranial aneurysms. On a 24-month period, 48 patients endovascularly treated by coiling and stenting (59 stents) for intracranial aneurysms were explored by flat panel detector CT technique. A sequence of 620 2D images was acquired over an angle of 240 using a 1,024 x 1,024 pixel matrix detector within a 48-cm field of view. The images were retrospectively analyzed independently by two neuroradiologists. Evaluation criteria were percentage of visualization of the stents and stent deployment (kinking or unsatisfactory deployment of the stent). Evaluation of the stent was feasible for all the patients. Stent visibility by XperCT was overall estimated at 76% of the stent length. Difficulties to analyze the stents were related to coil artifacts but not to packing density or aneurysm location. Stent length visualization was higher when the acquisition was performed before additional coiling (P < 0.0001). Mild kinking/misdeployment was noticed in 22% of the cases. XperCT technique provides multiplanar and 3D reconstructions that allows for a satisfying visualization of intracranial stents. This CT-like acquisition should be performed after the stent deployment and before coiling, in order to obtain better stent visualization. (orig.)

  9. Assessment and optimisation of the image quality of chest-radiography systems.

    Science.gov (United States)

    Redlich, U; Hoeschen, C; Doehring, W

    2005-01-01

    A complete evaluation strategy had been developed for thoracic X-ray imaging. It has been validated by investigating five chest-radiography systems, two of these systems after optimising image processing. The systems were a screen-film combination, a selenium drum, a conventional and a transparent imaging plate and a Cs/I-based flat panel detector (the two latter ones have been optimised using different post processing). At first all detectors have been characterised using physical parameters like DQE and MTF. After that all systems have been evaluated by human observer studies using anatomy in clinical images (VGA, ICS) and added pathological structures in thoracic phantom images (ROC). The ranking of the image quality of the systems was nearly the same in all studies. There was a similar assessment of main image quality parameters like spatial resolution, dynamic range and MTF. The modification of image post processing changed the visibility of pathological structures more than the visualisation of the anatomical criteria. The assessment of the clinical image quality has to be done for anatomical structures, and the recognition of pathological structures has to be evaluated.

  10. High-performance dual-energy imaging with a flat-panel detector: imaging physics from blackboard to benchtop to bedside

    Science.gov (United States)

    Siewerdsen, J. H.; Shkumat, N. A.; Dhanantwari, A. C.; Williams, D. B.; Richard, S.; Daly, M. J.; Paul, N. S.; Moseley, D. J.; Jaffray, D. A.; Yorkston, J.; Van Metter, R.

    2006-03-01

    The application of high-performance flat-panel detectors (FPDs) to dual-energy (DE) imaging offers the potential for dramatically improved detection and characterization of subtle lesions through reduction of "anatomical noise," with applications ranging from thoracic imaging to image-guided interventions. In this work, we investigate DE imaging performance from first principles of image science to preclinical implementation, including: 1.) generalized task-based formulation of NEQ and detectability as a guide to system optimization; 2.) measurements of imaging performance on a DE imaging benchtop; and 3.) a preclinical system developed in our laboratory for cardiac-gated DE chest imaging in a research cohort of 160 patients. Theoretical and benchtop studies directly guide clinical implementation, including the advantages of double-shot versus single-shot DE imaging, the value of differential added filtration between low- and high-kVp projections, and optimal selection of kVp pairs, filtration, and dose allocation. Evaluation of task-based NEQ indicates that the detectability of subtle lung nodules in double-shot DE imaging can exceed that of single-shot DE imaging by a factor of 4 or greater. Filter materials are investigated that not only harden the high-kVp beam (e.g., Cu or Ag) but also soften the low-kVp beam (e.g., Ce or Gd), leading to significantly increased contrast in DE images. A preclinical imaging system suitable for human studies has been constructed based upon insights gained from these theoretical and experimental studies. An important component of the system is a simple and robust means of cardiac-gated DE image acquisition, implemented here using a fingertip pulse oximeter. Timing schemes that provide cardiac-gated image acquisition on the same or successive heartbeats is described. Preclinical DE images to be acquired under research protocol will afford valuable testing of optimal deployment, facilitate the development of DE CAD, and support

  11. Comparison of flat-panel detector and image-intensifier detector for cone-beam CT.

    Science.gov (United States)

    Baba, Rika; Konno, Yasutaka; Ueda, Ken; Ikeda, Shigeyuki

    2002-01-01

    We evaluated a flat-panel detector (FPD) (scintillator screen and a-Si photo-sensor array) for use in a cone-beam computed tomography (CT) detector and compared it with an image-intensifier detector (IID). The FPD cone-beam CT system has a higher spatial resolution than the IID system. At equal pixel sizes, the standard deviation of noise intensity of the FPD system is equal to that of the IID system. However, the circuit noise of the FPD must be reduced, especially at low doses. Our evaluations show that the FPD system has a strong potential for use as a cone-beam CT detector because of high-spatial resolution.

  12. Modelling of scintillator based flat-panel detectors with Monte-Carlo simulations

    Science.gov (United States)

    Reims, N.; Sukowski, F.; Uhlmann, N.

    2011-01-01

    Scintillator based flat panel detectors are state of the art in the field of industrial X-ray imaging applications. Choosing the proper system and setup parameters for the vast range of different applications can be a time consuming task, especially when developing new detector systems. Since the system behaviour cannot always be foreseen easily, Monte-Carlo (MC) simulations are keys to gain further knowledge of system components and their behaviour for different imaging conditions. In this work we used two Monte-Carlo based models to examine an indirect converting flat panel detector, specifically the Hamamatsu C9312SK. We focused on the signal generation in the scintillation layer and its influence on the spatial resolution of the whole system. The models differ significantly in their level of complexity. The first model gives a global description of the detector based on different parameters characterizing the spatial resolution. With relatively small effort a simulation model can be developed which equates the real detector regarding signal transfer. The second model allows a more detailed insight of the system. It is based on the well established cascade theory, i.e. describing the detector as a cascade of elemental gain and scattering stages, which represent the built in components and their signal transfer behaviour. In comparison to the first model the influence of single components especially the important light spread behaviour in the scintillator can be analysed in a more differentiated way. Although the implementation of the second model is more time consuming both models have in common that a relatively small amount of system manufacturer parameters are needed. The results of both models were in good agreement with the measured parameters of the real system.

  13. Digital chest radiography: collimation and dose reduction

    DEFF Research Database (Denmark)

    Debess, Jeanne; Johnsen, Karen Kirstine; Vejle-Sørensen, Jens Kristian

    Purpose: Quality improvement of basic radiography focusing on collimation and dose reduction in digital chest radiography Methods and Materials:A retrospective study of digital chest radiography is performed to evaluate the primary x-ray tube collimation of the PA and lateral radiographs. Data from...... of clinical supervisors. Optimal collimation is determined by European and Regional Danish guidelines. The areal between current and optimal collimation is calculated. The experimental research is performed in September - October 2014 Siemens Axiom Aristos digital radiography system DR using 150 kV, 1,25 -3...

  14. The line-noise-reduction for low dose x-ray fluoroscopy with the flat panel detector

    Science.gov (United States)

    Nakamura, Tadashi; Ikeda, Shigeyuki; Suzuki, Katsumi; Takenouchi, Shinobu

    2006-03-01

    A scintillator type Flat Panel Detector (FPD)1 has a good noise performance especially in Fluoroscopic images because of high DQE. Almost same dose as I.I. and CCD system is accepted in clinical use. According to the clinical study, the dose in fluoroscopy will be decreased if we can reduce the line noise coming from gate line of the Thin Film Transistor (TFT). The purpose of this study is to detect and reduce this line noise from the fluoroscopic images making it possible to perform a lower dose of fluoroscopy imaging. We detected the line noise by acquiring a dark image (without exposure) and then comparing the average of the line data along to the gate line to the neighborhood lines. We have applied this method to the dark area taken by the collimator of the Lucite phantom image and detected it. The detected line will be compensated by interpolation with neighborhood lines. The FPD of our system2 has a big detecting area (40cm x 30cm) and a zoom mode is selected in fluoroscopy because the doctor is watching an edge of the guide-wire and a contrast medium. The collimated area of the detector is displayed in a monitor after the zooming process and we can take a collimated dark area for detecting the line noise. As we applied this method to the dark image (1024pixels x 1024lines) including 54 lines with noise, we can improve 10% of SD. Visible line noise of chest phantom image was reduced with this method. It will help to lower the fluoroscopy dose.

  15. Evaluation of imaging quality for flat-panel detector based low dose C-arm CT system

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Chang-Woo; Cha, Bo Kyung; Jeon, Sungchae; Huh, Young [Converged Medical Device Research Center, Advanced Medical Device Research Division, KERI, Gyeonggido 426-910 (Korea, Republic of)

    2015-07-01

    The image quality associated with the extent of the angle of gantry rotation, the number of projection views, and the dose of X-ray radiation was investigated in flat-panel detector (FPD) based C-arm cone-beam computed tomography (CBCT) system for medical applications. A prototype CBCT system for the projection acquisition used the X-ray tube (A-132, Varian inc.) having rhenium-tungsten molybdenum target and flat panel a-Si X-ray detector (PaxScan 4030CB, Varian inc.) having a 397 x 298 mm active area with 388 μm pixel pitch and 1024 x 768 pixels in 2 by 2 binning mode. The performance comparison of X-ray imaging quality was carried out using the Feldkamp, Davis, and Kress (FDK) reconstruction algorithm between different conditions of projection acquisition. In this work, head-and-dental (75 kVp/20 mA) and chest (90 kVp/25 mA) phantoms were used to evaluate the image quality. The 361 (30 fps x 12 s) projection data during 360 deg. gantry rotation with 1 deg. interval for the 3D reconstruction were acquired. Parke weighting function were applied to handle redundant data and improve the reconstructed image quality in a mobile C-arm system with limited rotation angles. The reconstructed 3D images were investigated for comparison of qualitative image quality in terms of scan protocols (projection views, rotation angles and exposure dose). Furthermore, the performance evaluation in image quality will be investigated regarding X-ray dose and limited projection data for a FPD based mobile C-arm CBCT system. (authors)

  16. Comparison of ring artifact removal methods using flat panel detector based CT images

    Directory of Open Access Journals (Sweden)

    Lee Soo Y

    2011-08-01

    Full Text Available Abstract Background Ring artifacts are the concentric rings superimposed on the tomographic images often caused by the defective and insufficient calibrated detector elements as well as by the damaged scintillator crystals of the flat panel detector. It may be also generated by objects attenuating X-rays very differently in different projection direction. Ring artifact reduction techniques so far reported in the literature can be broadly classified into two groups. One category of the approaches is based on the sinogram processing also known as the pre-processing techniques and the other category of techniques perform processing on the 2-D reconstructed images, recognized as the post-processing techniques in the literature. The strength and weakness of these categories of approaches are yet to be explored from a common platform. Method In this paper, a comparative study of the two categories of ring artifact reduction techniques basically designed for the multi-slice CT instruments is presented from a common platform. For comparison, two representative algorithms from each of the two categories are selected from the published literature. A very recently reported state-of-the-art sinogram domain ring artifact correction method that classifies the ring artifacts according to their strength and then corrects the artifacts using class adaptive correction schemes is also included in this comparative study. The first sinogram domain correction method uses a wavelet based technique to detect the corrupted pixels and then using a simple linear interpolation technique estimates the responses of the bad pixels. The second sinogram based correction method performs all the filtering operations in the transform domain, i.e., in the wavelet and Fourier domain. On the other hand, the two post-processing based correction techniques actually operate on the polar transform domain of the reconstructed CT images. The first method extracts the ring artifact template

  17. Practical expressions describing detective quantum efficiency in flat-panel detectors

    Science.gov (United States)

    Kim, H. K.

    2011-11-01

    In radiology, image quality excellence is a balance between system performance and patient dose, hence x-ray systems must be designed to ensure the maximum image quality is obtained for the lowest consistent dose. The concept of detective quantum efficiency (DQE) is widely used to quantify, understand, measure, and predict the performance of x-ray detectors and imaging systems. Cascaded linear-systems theory can be used to estimate DQE based on the system design parameters and this theoretical DQE can be utilized for determining the impact of various physical processes, such as secondary quantum sinks, noise aliasing, reabsorption noise, and others. However, the prediction of DQE usually requires tremendous efforts to determine each parameter consisting of the cascaded linear-systems model. In this paper, practical DQE formalisms assessing both the photoconductor- and scintillator-based flat-panel detectors under quantum-noise-limited operation are described. The developed formalisms are experimentally validated and discussed for their limits. The formalisms described in this paper would be helpful for the rapid prediction of the DQE performances of developing systems as well as the optimal design of systems.

  18. Resolution requirements for monitor viewing of digital flat-panel detector radiographs: a contrast detail analysis

    Science.gov (United States)

    Peer, Siegfried; Steingruber, Iris; Gassner, Eva; Peer, Regina; Giacomuzzi, Salvatore M.

    2002-05-01

    Since the introduction of digital flat panel detectors into clinical routine the discussion on monitor specifications for primary soft copy reading has gained new impetus. Major concerns exist for viewing of tiny opacities such as pulmonary nodules. In this study CDRAD phantom images were acquired on a caesium iodid/amorphous silicon detector at varying exposure levels. Images were read three times by three observers on a clinical 1K and 2K monitor workstation. All typical workstation functions such as magnification and window/level setting were applied during image reading. Correct detection ratios were calculated according to the CDRAD evaluation manual. Observer ratings were highest for high dose exposure and 2K monitor reading. No significant difference was detected in the correct detection ratio of observers. However, the difference between the two types of workstations (1K versus 2K monitors) despite less than 3% was significant at a 95% confidence level. This is in good accordance with recently published clinical studies. However, further clinical work will be needed to strengthen this laboratory based impression. Given these subtle differences in low contrast detail detection on 1K and 2K clinical PACS workstation we should probably rethink the recommendations of various national boards for the use of 2K monitors.

  19. Dynamic dual-energy chest radiography: a potential tool for lung tissue motion monitoring and kinetic study.

    Science.gov (United States)

    Xu, Tong; Ducote, Justin L; Wong, Jerry T; Molloi, Sabee

    2011-02-21

    Dual-energy chest radiography has the potential to provide better diagnosis of lung disease by removing the bone signal from the image. Dynamic dual-energy radiography is now possible with the introduction of digital flat-panel detectors. The purpose of this study is to evaluate the feasibility of using dynamic dual-energy chest radiography for functional lung imaging and tumor motion assessment. The dual-energy system used in this study can acquire up to 15 frames of dual-energy images per second. A swine animal model was mechanically ventilated and imaged using the dual-energy system. Sequences of soft-tissue images were obtained using dual-energy subtraction. Time subtracted soft-tissue images were shown to be able to provide information on regional ventilation. Motion tracking of a lung anatomic feature (a branch of pulmonary artery) was performed based on an image cross-correlation algorithm. The tracking precision was found to be better than 1 mm. An adaptive correlation model was established between the above tracked motion and an external surrogate signal (temperature within the tracheal tube). This model is used to predict lung feature motion using the continuous surrogate signal and low frame rate dual-energy images (0.1-3.0 frames per second). The average RMS error of the prediction was (1.1 ± 0.3) mm. The dynamic dual energy was shown to be potentially useful for lung functional imaging such as regional ventilation and kinetic studies. It can also be used for lung tumor motion assessment and prediction during radiation therapy.

  20. Quantitative evaluation of anatomical noise in chest digital tomosynthesis, digital radiography, and computed tomography

    Science.gov (United States)

    Lee, D.; Choi, S.; Lee, H.; Kim, D.; Choi, S.; Kim, H.-J.

    2017-04-01

    Lung cancer is currently the worldwide leading cause of death from cancer. Thus, detection of lung cancer at its early stages is critical for improving the survival rate of patients. Chest digital tomosynthesis (CDT) is a recently developed imaging modality, combining many advantages of digital radiography (DR) and computed tomography (CT). This method has the potential to be widely used in the clinical setting. In this study, we introduce a developed CDT R/F system and compare its image quality with those of DR and CT, especially with respect to anatomical noise and lung nodule conspicuity, for LUNGMAN phantoms. The developed CDT R/F system consists of a CsI scintillator flat panel detector, X-ray tube, and tomosynthesis data acquisition geometry. For CDT R/F imaging, 41 projections were acquired at different angles, over the ± 20° angular range, in a linear translation geometry. To evaluate the clinical effectiveness of the CDT R/F system, the acquired images were compared with CT (Philips brilliance CT 64, Philips healthcare, U.S.) and DR (ADR-M, LISTEM, Korea) phantom images in terms of the anatomical noise power spectrum (aNPS). DR images exhibited low conspicuity for a small-size lung nodule, while CDT R/F and CT exhibited relatively high sensitivity for all lung nodule sizes. The aNPS of the CDT R/F system was better than that of DR, by resolving anatomical overlapping problems. In conclusion, the developed CDT R/F system is likely to contribute to early diagnosis of lung cancer, while requiring a relatively low patient dose, compared with CT.

  1. Comparison measurements of DQE for two flat panel detectors: fluoroscopic detector vs. cone beam CT detector

    Science.gov (United States)

    Betancourt Benítez, Ricardo; Ning, Ruola; Conover, David

    2006-03-01

    The physical performance of two flat panel detectors (FPD) has been evaluated using a standard x-ray beam quality set by IEC, namely RQA5. The FPDs evaluated in this study are based on an amorphous silicon photodiode array that is coupled to a thallium-doped Cesium Iodide scintillator and to a thin film transistor (TFT) array. One detector is the PaxScan 2520 that is designed for fluoro imaging, and has a small dynamic range and a large image lag. The other detector is the PaxScan 4030CB that is designed for cone beam CT, and has a large dynamic range (>16-bit), a reduced image lag and many imaging modes. Varian Medical Systems manufactured both detectors. The linearity of the FPDs was investigated by using an ionization chamber and aluminum filtration in order to obtain the beam quality. Since the FPDs are used in fluoroscopic mode, image lag of the FPD was measured in order to investigate its effect on this study, especially its effect on DQE. The spatial resolution of the FPDs was determined by obtaining the pre-sampling modulation transfer function for each detector. A sharp edge was used in accordance to IEC 62220-1. Next, the Normalized Noise Power Spectrum (NNPS) was calculated for various exposures levels at RQA5 radiation quality. Finally, the DQE of each FPD was obtained with a modified version of the international standard set by IEC 62220-1. The results show that the physical performance in DQE and MTF of the PaxScan 4030CB is superior to that of PaxScan2520.

  2. Interpretation of neonatal chest radiography

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Hye Kyung [Dept. of Radiology, Kangwon National University Hospital, Chuncheon (Korea, Republic of)

    2016-05-15

    Plain radiographs for infants in the neonatal intensive care unit are obtained using the portable X-ray equipment in order to evaluate the neonatal lungs and also to check the position of the tubes and catheters used for monitoring critically-ill neonates. Neonatal respiratory distress is caused by a variety of medical or surgical disease conditions. Clinical information about the gestational week, respiratory symptoms, and any events during delivery is essential for interpretation of the neonatal chest radiographs. Awareness of common chest abnormality in the prematurely born or term babies is also very important for chest evaluation in the newborn. Furthermore, knowledge about complications such as air leaks and bronchopulmonary dysplasia following treatment are required to accurately inform the clinicians. The purpose of this article was to briefly review radiographic findings of chest diseases in newborns that are relatively common in daily practice.

  3. A flat-panel detector based micro-CT system: performance evaluation for small-animal imaging.

    Science.gov (United States)

    Lee, Sang Chul; Kim, Ho Kyung; Chun, In Kon; Cho, Myung Hye; Lee, Soo Yeol; Cho, Min Hyoung

    2003-12-21

    A dedicated small-animal x-ray micro computed tomography (micro-CT) system has been developed to screen laboratory small animals such as mice and rats. The micro-CT system consists of an indirect-detection flat-panel x-ray detector with a field-of-view of 120 x 120 mm2, a microfocus x-ray source, a rotational subject holder and a parallel data processing system. The flat-panel detector is based on a matrix-addressed photodiode array fabricated by a CMOS (complementary metal-oxide semiconductor) process coupled to a CsI:T1 (thallium-doped caesium iodide) scintillator as an x-ray-to-light converter. Principal imaging performances of the micro-CT system have been evaluated in terms of image uniformity, voxel noise and spatial resolution. It has been found that the image non-uniformity mainly comes from the structural non-uniform sensitivity pattern of the flat-panel detector and the voxel noise is about 48 CT numbers at the voxel size of 100 x 100 x 200 microm3 and the air kerma of 286 mGy. When the magnification ratio is 2, the spatial resolution of the micro-CT system is about 14 1p/mm (line pairs per millimetre) that is almost determined by the flat-panel detector showing about 7 1p/mm resolving power. Through low-contrast phantom imaging studies, the minimum resolvable contrast has been found to be less than 36 CT numbers at the air kerma of 95 mGy. Some laboratory rat imaging results are presented.

  4. Calibration model of a dual gain flat panel detector for 2D and 3D x-ray imaging.

    Science.gov (United States)

    Schmidgunst, C; Ritter, D; Lang, E

    2007-09-01

    The continuing research and further development in flat panel detector technology have led to its integration into more and more medical x-ray systems for two-dimensional (2D) and three-dimensional (3D) imaging, such as fixed or mobile C arms. Besides the obvious advantages of flat panel detectors, like the slim design and the resulting optimum accessibility to the patient, their success is primarily a product of the image quality that can be achieved. The benefits in the physical and performance-related features as opposed to conventional image intensifier systems, (e.g., distortion-free reproduction of imaging information or almost linear signal response over a large dynamic range) can be fully exploited, however, only if the raw detector images are correctly calibrated and postprocessed. Previous procedures for processing raw data contain idealizations that, in the real world, lead to artifacts or losses in image quality. Thus, for example, temperature dependencies or changes in beam geometry, as can occur with mobile C arm systems, have not been taken into account up to this time. Additionally, adverse characteristics such as image lag or aging effects have to be compensated to attain the best possible image quality. In this article a procedure is presented that takes into account the important dependencies of the individual pixel sensitivity of flat panel detectors used in 2D or 3D imaging and simultaneously minimizes the work required for an extensive recalibration. It is suitable for conventional detectors with only one gain mode as well as for the detectors specially developed for 3D imaging with dual gain read-out technology.

  5. A flat-panel detector based micro-CT system: performance evaluation for small-animal imaging

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sang Chul; Kim, Ho Kyung; Chun, In Kon; Cho, Myung Hye; Lee, Soo Yeol; Cho, Min Hyoung [Graduate School of East-West Medical Science, Kyung Hee University, 1 Seochun, Kiheung, Yongin, Kyungki 449-701 (Korea, Republic of)

    2003-12-21

    A dedicated small-animal x-ray micro computed tomography (micro-CT) system has been developed to screen laboratory small animals such as mice and rats. The micro-CT system consists of an indirect-detection flat-panel x-ray detector with a field-of-view of 120 x 120 mm{sup 2}, a microfocus x-ray source, a rotational subject holder and a parallel data processing system. The flat-panel detector is based on a matrix-addressed photodiode array fabricated by a CMOS (complementary metal-oxide semiconductor) process coupled to a CsI:Tl (thallium-doped caesium iodide) scintillator as an x-ray-to-light converter. Principal imaging performances of the micro-CT system have been evaluated in terms of image uniformity, voxel noise and spatial resolution. It has been found that the image non-uniformity mainly comes from the structural non-uniform sensitivity pattern of the flat-panel detector and the voxel noise is about 48 CT numbers at the voxel size of 100 x 100 x 200 {mu}m{sup 3} and the air kerma of 286 mGy. When the magnification ratio is 2, the spatial resolution of the micro-CT system is about 14 lp/mm (line pairs per millimetre) that is almost determined by the flat-panel detector showing about 7 lp/mm resolving power. Through low-contrast phantom imaging studies, the minimum resolvable contrast has been found to be less than 36 CT numbers at the air kerma of 95 mGy. Some laboratory rat imaging results are presented.

  6. Performance Study of an aSi Flat Panel Detector for Fast Neutron Imaging of Nuclear Waste

    Energy Technology Data Exchange (ETDEWEB)

    Schumann, M.; Mauerhofer, E. [Institute of Energy and Climate Research - Nuclear Waste Management and Reactor Safety, Forschungszentrum Juelich GmbH, 52425 Juelich (Germany); Engels, R.; Kemmerling, G. [Central Institute for Engineering, Electronics and Analytics - Electronic Systems, Forschungszentrum Juelich GmbH, 52425 Juelich (Germany); Frank, M. [MATHCCES - Department of Mathematics, RWTH Aachen University, 52062 Aachen (Germany); Havenith, A.; Kettler, J.; Klapdor-Kleingrothaus, T. [Institute of Nuclear Engineering and Technology Transfer, RWTH Aachen University, 52062 Aachen (Germany); Schitthelm, O. [Corporate Technology, Siemens AG, 91058 Erlangen (Germany)

    2015-07-01

    Radioactive waste must be characterized to check its conformance for intermediate storage and final disposal according to national regulations. For the determination of radio-toxic and chemo-toxic contents of radioactive waste packages non-destructive analytical techniques are preferentially used. Fast neutron imaging is a promising technique to assay large and dense items providing, in complementarity to photon imaging, additional information on the presence of structures in radioactive waste packages. Therefore the feasibility of a compact Neutron Imaging System for Radioactive waste Analysis (NISRA) using 14 MeV neutrons is studied in a cooperation framework of Forschungszentrum Juelich GmbH, RWTH Aachen University and Siemens AG. However due to the low neutron emission of neutron generators in comparison to research reactors the challenging task resides in the development of an imaging detector with a high efficiency, a low sensitivity to gamma radiation and a resolution sufficient for the purpose. The setup is composed of a commercial D-T neutron generator (Genie16GT, Sodern) with a surrounding shielding made of polyethylene, which acts as a collimator and an amorphous silicon flat panel detector (aSi, 40 x 40 cm{sup 2}, XRD-1642, Perkin Elmer). Neutron detection is achieved using a general propose plastic scintillator (EJ-260, Eljen Technology) linked to the detector. The thermal noise of the photodiodes is reduced by employing an entrance window made of aluminium. Optimal gain and integration time for data acquisition are set by measuring the response of the detector to the radiation of a 500 MBq {sup 241}Am-source. Detector performance was studied by recording neutron radiography images of materials with various, but well known, chemical compositions, densities and dimensions (Al, C, Fe, Pb, W, concrete, polyethylene, 5 x 8 x 10 cm{sup 3}). To simulate gamma-ray emitting waste radiographs in presence of a gamma-ray sources ({sup 60}Co, {sup 137}Cs, {sup 241

  7. Measurements of the modulation transfer function, normalized noise power spectrum and detective quantum efficiency for two flat panel detectors: a fluoroscopic and a cone beam computer tomography flat panel detectors.

    Science.gov (United States)

    Benítez, Ricardo Betancourt; Ning, Ruola; Conover, David; Liu, Shaohua

    2009-01-01

    The physical performance of two Flat Panel Detectors has been evaluated. The first Flat Panel Detector is for Fluoroscopic applications, Varian PaxScan 2520, and the second is for Cone Beam Computer Tomography applications, Varian PaxScan 4030CB. First, the spectrum of the X-ray source was measured. Second, the linearity of the detectors was investigated by using an ionization chamber and the average ADU values of the detectors. Third, the temporal resolution was characterized by evaluating their image lag. Fourth, their spatial resolution was characterized by the pre-sampling Modulation Transfer Function. Fifth, the Normalized Noise Power Spectrum was calculated for various exposures levels. Finally, the Detective Quantum Efficiency was obtained as a function of spatial frequency and entrance exposure. The results illustrate that the physical performance in Detective Quantum Efficiency and Normalized Noise Power Spectrum of the Cone Beam Computer Tomography detector is superior to that of the fluoroscopic detector whereas the latter detector has a higher spatial resolution as demonstrated by larger values of its Modulation Transfer Function at large spatial frequencies.

  8. Preliminary performance of image quality for a low-dose C-arm CT system with a flat-panel detector

    Energy Technology Data Exchange (ETDEWEB)

    Kyung Cha, Bo [Advanced Medical Device Research Center, Korea Electrotechnology Research Institute, Ansan (Korea, Republic of); Seo, Chang-Woo [Department of Radiation Convergence Engineering, College of Health Science, Yonsei University, Wonju (Korea, Republic of); Yang, Keedong [Advanced Medical Device Research Center, Korea Electrotechnology Research Institute, Ansan (Korea, Republic of); Jeon, Seongchae, E-mail: sarim@keri.re.kr [Advanced Medical Device Research Center, Korea Electrotechnology Research Institute, Ansan (Korea, Republic of); Huh, Young [Advanced Medical Device Research Center, Korea Electrotechnology Research Institute, Ansan (Korea, Republic of)

    2015-06-01

    Digital flat panel imager (FPI)-based cone-beam computed tomography (CBCT) has been widely used in C-arm imaging for spine surgery and interventional procedures. The system provides real-time fluoroscopy with high spatial resolution and three-dimensional (3D) visualization of anatomical structure without the need for patient transportation in interventional suite. In this work, a prototype CBCT imaging platform with continuous single rotation about the gantry was developed by using a large-area flat-panel detector with amorphous Si-based thin film transistor matrix. The different 2D projection images were acquired during constant gantry velocity for reconstructed images at a tube voltage of 80–120 kVp, and different current (10–50 mA) conditions. Various scan protocols were applied to a chest phantom human by changing the number of projection images and scanning angles. The projections were then reconstructed into a volumetric data of sections by using a 3D reconstruction algorithm (e.g., filtered back projection). The preliminary quantitative X-ray performance of our CBCT system was investigated by using the American Association of Physicists in Medicine CT phantom in terms of spatial resolution, contrast resolution, and CT number linearity for mobile or fixed C-arm based CBCT application with limited rotational geometry. The novel results of the projection data with different scanning angles and angular increments in the orbital gantry platform were acquired and evaluated experimentally.

  9. Preliminary performance of image quality for a low-dose C-arm CT system with a flat-panel detector

    Science.gov (United States)

    Kyung Cha, Bo; Seo, Chang-Woo; Yang, Keedong; Jeon, Seongchae; Huh, Young

    2015-06-01

    Digital flat panel imager (FPI)-based cone-beam computed tomography (CBCT) has been widely used in C-arm imaging for spine surgery and interventional procedures. The system provides real-time fluoroscopy with high spatial resolution and three-dimensional (3D) visualization of anatomical structure without the need for patient transportation in interventional suite. In this work, a prototype CBCT imaging platform with continuous single rotation about the gantry was developed by using a large-area flat-panel detector with amorphous Si-based thin film transistor matrix. The different 2D projection images were acquired during constant gantry velocity for reconstructed images at a tube voltage of 80-120 kVp, and different current (10-50 mA) conditions. Various scan protocols were applied to a chest phantom human by changing the number of projection images and scanning angles. The projections were then reconstructed into a volumetric data of sections by using a 3D reconstruction algorithm (e.g., filtered back projection). The preliminary quantitative X-ray performance of our CBCT system was investigated by using the American Association of Physicists in Medicine CT phantom in terms of spatial resolution, contrast resolution, and CT number linearity for mobile or fixed C-arm based CBCT application with limited rotational geometry. The novel results of the projection data with different scanning angles and angular increments in the orbital gantry platform were acquired and evaluated experimentally.

  10. Comparative Analysis between Two Amorphous Silicon Flat-panel Detector:Radiation Dose and Image Quality%碘化铯和硫氯化钆在DR系统中剂量与图像质量的分析

    Institute of Scientific and Technical Information of China (English)

    张志奎; 梁吉

    2014-01-01

    目的:比较碘化铯和硫氧化钆2种闪烁体材料平板探测器的DR系统在不同成像剂量条件下图像质量的差别。方法:以碘化铯为闪烁体材料的平板探测器系统和以硫氧化钆为闪烁体材料的平板探测器系统分别摄取对比度-细节体模(CDRAD 2.0)在相近成像剂量条件下的X射线图像,计算所对应的成像剂量下图像质量因子反数值(image quality figure inverse,IQFinv),应用ANOVA分析2平板探测器对比度及细节检测能力,应用Wilcoxon检验分析、比较2种平板探测器的图像信息检测能力的差别。结果:在一定剂量范围内,2种平板探测器的图像质量均随着成像剂量的增加而增加(P<0.001)。在管电流量不同mAs时,2种非晶硅DR平板探测器的IQFinv值差异无统计学意义(P>0.05)。结论:成像剂量相同时,2种非晶硅平板探测器具有近似的图像质量,图像质量的提高与成像剂量的增加并不成线性关系。%Objective:To assess and compare the image quality at different exposures ettings using cesium iodide (CsI) flat-panel detector digital radiography system and GOS flat-panel detector digital radiography system. Methods: The images of contrast-detail phantom (CDRAD2.0) were taken at different exposure settings for two flat-panel detector systems. The image quality figure inverse (IQFinv) for different dose settings was calculated. The detectability of two system in contrast and detail was analysed using ANOVA. The statistical significance was evaluated using the Wilcoxon test between two system. Results: At certain dose range, the image quality improved with radiation dose increased for two amorphous silicon flat-panel detector system(P0.05). Conclusion:At the same radiation dose, two flat-panel detector systems have approximately image quality. There is not linear relevance between image quality improvement and radiation dose augment.

  11. Comparative Analysis between Two Amorphous Silicon Flat-panel Detector: Radiation Dose and Image Quality%2种非晶硅DR平板探测器成像剂量与图像质量的比较分析

    Institute of Scientific and Technical Information of China (English)

    曹国全; 许化致; 潘克华; 孙厚长

    2011-01-01

    Objective To assess and compare the image quality at different exposure settings using cesium iodide (CsI) flat-panel detector digital radiography system and GOS flat-panel detector digital radiography system. Methods The images of contrast-detail phantom (CDRAD2. 0) were taken at different exposure settings for two flat-panel detector systems. The image quality figure inverse(IQFinv) for different dose settings was calculated. The detectability of two system in contrast and detail was analysed using ANOVA . The statistical significance was evaluated using the Wilcoxon test between two system. Results At certain dose range, the image quality improved with radiation dose increased for two amorphous silicon flat-panel detector system(P<O. 001). At different mAs value of tube current dosage,the IQFinv was no of statistical significance between two system(P>O. 05). Conclusion At the same radiation dose,two flat-panel detector systems have approximately image quality. There is not linear relevance between image quality improvement and radiation dose augment.%目的 比较碘化铯和硫氧化钆2种闪烁体材料平板探测器的DR系统在不同成像剂量条件下图像质量的差别.方法 以碘化铯为闪烁体材料的平板探测器系统和以硫氧化钆为闪烁体材料的平板探测器系统分别摄取对比度-细节体模(CDRAD 2.0)在相近成像剂量条件下的X射线图像,计算所对应的成像剂量下图像质量因子反数值(image quality figure inverse,IQFinv),应用ANOVA 分析2平板探测器对比度及细节检测能力,应用Wilcoxon检验分析、比较2种平板探测器的图像信息检测能力的差别.结果 在一定剂量范围内,2种平板探测器的图像质量均随着成像剂量的增加而增加(P<0.001).在管电流量不同mAs时,2种非晶硅DR平板探测器的IQFinv值差异无统计学意义(P>0.05).结论 成像剂量相同时,2种非晶硅平板探测器具有近似的图像质量,图像质量的

  12. Bacteriological research for the contamination of equipment in chest radiography

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Seung Gu; Song, Woon Heung; Kweon, Dae Cheol [Shinhan University, Uijeongbu (Korea, Republic of)

    2015-12-15

    The purpose is to determine the degree of contamination of the equipment for infection control in chest radiography of the radiology department. We confirmed by chemical and bacterial identification of bacteria of the equipment and established a preventive maintenance plan. Chest X-ray radiography contact area on the instrument patients shoulder, hand, chin, chest lateral radiography patient contact areas with a 70% isopropyl alcohol cotton swab were compared to identify the bacteria before and after sterilization on the patient contact area in the chest radiography equipment of the department. The gram positive Staphylococcus was isolated from side shoots handle before disinfection in the chest radiography equipment. For the final identification of antibiotic tested that it was determined by performing the nobobiocin to the sensitive Staphylococcus epidermidis. Chest radiography equipment before disinfecting the handle side of Staphylococcus epidermidis bacteria were detected using a disinfectant should be to prevent hospital infections.

  13. Radiation dose reduction using a CdZnTe-based computed tomography system: Comparison to flat-panel detectors

    Energy Technology Data Exchange (ETDEWEB)

    Le, Huy Q.; Ducote, Justin L.; Molloi, Sabee [Department of Radiological Sciences, University of California, Irvine, California 92697 (United States)

    2010-03-15

    Purpose: Although x-ray projection mammography has been very effective in early detection of breast cancer, its utility is reduced in the detection of small lesions that are occult or in dense breasts. One drawback is that the inherent superposition of parenchymal structures makes visualization of small lesions difficult. Breast computed tomography using flat-panel detectors has been developed to address this limitation by producing three-dimensional data while at the same time providing more comfort to the patients by eliminating breast compression. Flat panels are charge integrating detectors and therefore lack energy resolution capability. Recent advances in solid state semiconductor x-ray detector materials and associated electronics allow the investigation of x-ray imaging systems that use a photon counting and energy discriminating detector, which is the subject of this article. Methods: A small field-of-view computed tomography (CT) system that uses CdZnTe (CZT) photon counting detector was compared to one that uses a flat-panel detector for different imaging tasks in breast imaging. The benefits afforded by the CZT detector in the energy weighting modes were investigated. Two types of energy weighting methods were studied: Projection based and image based. Simulation and phantom studies were performed with a 2.5 cm polymethyl methacrylate (PMMA) cylinder filled with iodine and calcium contrast objects. Simulation was also performed on a 10 cm breast specimen. Results: The contrast-to-noise ratio improvements as compared to flat-panel detectors were 1.30 and 1.28 (projection based) and 1.35 and 1.25 (image based) for iodine over PMMA and hydroxylapatite over PMMA, respectively. Corresponding simulation values were 1.81 and 1.48 (projection based) and 1.85 and 1.48 (image based). Dose reductions using the CZT detector were 52.05% and 49.45% for iodine and hydroxyapatite imaging, respectively. Image-based weighting was also found to have the least beam

  14. Cone beam breast CT with a high pitch (75 μm), thick (500 μm) scintillator CMOS flat panel detector: Visibility of simulated microcalcifications

    OpenAIRE

    2013-01-01

    Purpose: To measure and investigate the improvement of microcalcification (MC) visibility in cone beam breast CT with a high pitch (75 μm), thick (500 μm) scintillator CMOS/CsI flat panel detector (Dexela 2923, Perkin Elmer).

  15. Application of the Monte Carlo method to analyze materials used in flat panel detectors to obtain X-ray spectra

    Science.gov (United States)

    Gallardo, Sergio; Pozuelo, Fausto; Querol, Andrea; Ródenas, José; Verdú, Gumersindo

    2014-06-01

    An accurate knowledge of the photon spectra emitted by X-ray tubes in radiodiagnostic is essential to better estimate the imparted dose to patients and to improve the quality image obtained with these devices. In this work, it is proposed the use of a flat panel detector together with a PMMA wedge to estimate the actual X-ray spectrum using the Monte Carlo method and unfolding techniques. The MCNP5 code has been used to model different flat panels (based on indirect and direct methods to produce charge carriers from absorbed X-rays) and to obtain the dose curves and system response functions. Most of the actual flat panel devices use scintillator materials that present K-edge discontinuities in the mass energy-absorption coefficient, which strongly affect the response matrix. In this paper, the applicability of different flat panels for reconstructing X-ray spectra is studied. The effect of the mass energy-absorption coefficient of the scintillator material has been studied on the response matrix and consequently, in the reconstructed spectra. Different unfolding methods are tested to reconstruct the actual X-ray spectrum knowing the dose curve and the response function. It has been concluded that the regularization method MTSVD is appropriate to unfold X-ray spectra in all the scintillators studied.

  16. Aging of imaging properties of a CMOS flat-panel detector for dental cone-beam computed tomography

    Science.gov (United States)

    Kim, D. W.; Han, J. C.; Yun, S.; Kim, H. K.

    2017-01-01

    We have experimentally investigated the long-term stability of imaging properties of a flat-panel detector in conditions used for dental x-ray imaging. The detector consists of a CsI:Tl layer and CMOS photodiode pixel arrays. Aging simulations were carried out using an 80-kVp x-ray beam at an air-kerma rate of approximately 5 mGy s-1 at the entrance surface of the detector with a total air kerma of up to 0.6 kGy. Dark and flood-field images were periodically obtained during irradiation, and the mean signal and noise levels were evaluated for each image. We also evaluated the modulation-transfer function (MTF), noise-power spectrum (NPS), and detective quantum efficiency (DQE). The aging simulation showed a decrease in both the signal and noise of the gain-offset-corrected images, but there was negligible change in the signal-to-noise performance as a function of the accumulated dose. The gain-offset correction for analyzing images resulted in negligible changes in MTF, NPS, and DQE results over the total dose. Continuous x-ray exposure to a detector can cause degradation in the physical performance factors such the detector sensitivity, but linear analysis of the gain-offset-corrected images can assure integrity of the imaging properties of a detector during its lifetime.

  17. Percutaneous Glycerol Rhizotomy for Trigeminal Neuralgia Using a Single-Plane, Flat Panel Detector Angiography System: Technical Note

    Science.gov (United States)

    ARISHIMA, Hidetaka; KAWAJIRI, Satoshi; ARAI, Hiroshi; HIGASHINO, Yoshifumi; KODERA, Toshiaki; KIKUTA, Ken-ichiro

    2016-01-01

    Percutaneous treatments for trigeminal neuralgia (TN) including glycerol rhizotomy (GR), radiofrequency thermocoagulation (RT), and balloon compression (BC) are effective for patients with medical comorbidities and risk factors of microvascular decompression (MVD). These procedures are usually performed under fluoroscopy. Surgeons advance the needle to the trigeminal plexus through the foramen ovale while observing landmarks of fluoroscopic images; however, it is sometimes difficult to appropriately place the needle tip in Meckel’s cave. We present the technical details of percutaneous GR using a single-plane, flat panel detector angiography system to check the needle positioning. When the needle tip may be located near the trigeminal cistern, three-dimensional (3-D) bone images are taken with cone-beam computed tomography (CT). These images clearly show the position of the needle tip in Meckel’s cave. If it is difficult to place it through the foramen ovale, surgeons perform cone beam CT to observe the actual position of the needle tip at the skull base. After confirming the positional relation between the needle tip and foramen ovale, surgeons can advance it in the precise direction. In 10 procedures, we could place the nerve-block needle in about 14.5 minutes on average without complications. We think that our method is simple and convenient for percutaneous treatments for TN, and it may be helpful for surgeons to perform such treatments. PMID:27041633

  18. Feasibility and potential value of flat-panel detector-based computed tomography in myelography after spinal surgery.

    Science.gov (United States)

    Kau, Thomas; Rabitsch, Egon; Celedin, Stefan; Jeschofnig, Barbara; Illiasch, Herbert; Eicher, Wolfgang; Uhl, Eberhard; Honl, Matthias; Hausegger, Klaus Armin

    2009-01-01

    The purpose of this study was to assess the value of myelography using flat-panel detector-based computed tomography (fpCT) in 5 patients in whom the image quality of multislice CT (MSCT) or MR imaging was limited by metal artifacts. The application of fpCT to myelographic imaging of the lumbar spine and cervicothoracic junction after surgery was feasible. Multiplanar, preferably sagittal, and 3D reconstructions adequately depicted disc space implants and provided high resolution images of osseous structures. The images obtained with fpCT allowed evaluation of anatomical details such as single nerve roots and proved especially valuable in a patient with impaired MR imaging results caused by metal artifacts from an intraoperative abrasion. In a case of recurrent disc herniation, imaging results of myelographic fpCT and MSCT scanning were in good agreement. The novel imaging technique the authors describe yielded adequate results in patients with a history of spinal surgery, may be superior to MSCT scanning in depicting osseous structures and metallic implants, and has the potential to provide multilevel spinal images. Myelographic fpCT scanning may be the preferred modality in patients with expected or known metal artifacts on myelographic MSCT scans and/or MR images.

  19. Visualization of novel microstents in patients with unruptured intracranial aneurysms with contrast-enhanced flat panel detector CT

    Energy Technology Data Exchange (ETDEWEB)

    Poncyljusz, Wojciech, E-mail: wponcyl@poczta.onet.pl [Departament of Interventional Radiology, Pomeranian Medical University, Neurointerventional Cath Lab MSW Hospital, Al. Powst. Wielkopolskich 72, 70-111 Szczecin (Poland); Zwarzany, Łukasz, E-mail: zwarzany@gmail.com [Departament of Interventional Radiology, Pomeranian Medical University, Neurointerventional Cath Lab MSW Hospital, Al. Powst. Wielkopolskich 72, 70-111 Szczecin (Poland); Safranow, Krzysztof, E-mail: chrissaf@mp.pl [Department of Biochemistry and Chemistry, Pomeranian Medical University, Al. Powst. Wielkopolskich 72, 70-111 Szczecin (Poland)

    2015-07-15

    Highlights: • We examine the feasibility of FPDCT for visualizing intracranial microstents. • Stent deployment and its apposition to the vessel wall are easily assessable. • Coil streaking artifacts hamper the assessment of stent visibility. - Abstract: Objectives: The aim of our study was to evaluate the feasibility of contrast-enhanced flat panel detector CT (FPDCT) for visualizing the novel microstents implanted in patients with unruptured wide-necked intracranial aneurysms. Methods: Forty-four cases of patients who underwent stent assisted coiling at our department were retrospectively analyzed. In each case, FPDCT images were performed after stent and coils deployment and then assessed in the terms of stent struts and all radiopaque markers and tantalum strands visibility separately using a 3-grade scale (1 – inadequate, 2 – good, 3 – excellent). Results: Stent struts visibility was assessed to be inadequate for evaluation in all cases. All radiopaque markers and tantalum strands visibility was excellent in 61.4% and good in 38.6% of cases. We observed 4 (9.09%) cases of incomplete stent opening. Treated aneurysm size <10 mm was an independent predictor of excellent stent all radiopaque markers and tantalum strands visibility (ρ = 0.014). Conclusions: Contrast-enhanced FPDCT is feasible for visualizing stents implanted in patients with intracranial aneurysms as it gives precise visualization of the relationships between the stent tantalum strands and the vessel wall. Stents used in the treatment of aneurysms ≥10 mm in size are worse visualized because of the coil streaking artifacts.

  20. Percutaneous Glycerol Rhizotomy for Trigeminal Neuralgia Using a Single-Plane, Flat Panel Detector Angiography System: Technical Note.

    Science.gov (United States)

    Arishima, Hidetaka; Kawajiri, Satoshi; Arai, Hiroshi; Higashino, Yoshifumi; Kodera, Toshiaki; Kikuta, Ken-Ichiro

    2016-05-15

    Percutaneous treatments for trigeminal neuralgia (TN) including glycerol rhizotomy (GR), radiofrequency thermocoagulation (RT), and balloon compression (BC) are effective for patients with medical comorbidities and risk factors of microvascular decompression (MVD). These procedures are usually performed under fluoroscopy. Surgeons advance the needle to the trigeminal plexus through the foramen ovale while observing landmarks of fluoroscopic images; however, it is sometimes difficult to appropriately place the needle tip in Meckel's cave. We present the technical details of percutaneous GR using a single-plane, flat panel detector angiography system to check the needle positioning. When the needle tip may be located near the trigeminal cistern, three-dimensional (3-D) bone images are taken with cone-beam computed tomography (CT). These images clearly show the position of the needle tip in Meckel's cave. If it is difficult to place it through the foramen ovale, surgeons perform cone beam CT to observe the actual position of the needle tip at the skull base. After confirming the positional relation between the needle tip and foramen ovale, surgeons can advance it in the precise direction. In 10 procedures, we could place the nerve-block needle in about 14.5 minutes on average without complications. We think that our method is simple and convenient for percutaneous treatments for TN, and it may be helpful for surgeons to perform such treatments.

  1. Morphologic Changes of Mammary Carcinomas in Mice over Time as Monitored by Flat-Panel Detector Volume Computed Tomography

    Directory of Open Access Journals (Sweden)

    Jeannine Missbach-Guentner

    2008-07-01

    Full Text Available Noninvasive methods are strongly needed to detect and quantify not only tumor growth in murine tumor models but also the development of vascularization and necrosis within tumors. This study investigates the use of a new imaging technique, flat-panel detector volume computed tomography (fpVCT, to monitor in vivo tumor progression and structural changes within tumors of two murine carcinoma models. After tumor cell inoculation, single fpVCT scans of the entire mice were performed at different time points. The acquired isotropic, high-resolution volume data sets enable an accurate real-time assessment and precise measurements of tumor volumes. Spreading of contrast agent-containing blood vessels around and within the tumors was clearly visible over time. Furthermore, fpVCT permits the identification of differences in the uptake of contrast media within tumors, thus delineating necrosis, tumor tissues, and blood vessels. Classification of tumor tissues based on the decomposition of the underlying mixture distribution of tissue-related Hounsfield units allowed the quantitative acquisition of necrotic tissues at each time point. Morphologic alterations of the tumor depicted by fpVCT were confirmed by histopathologic examination. Concluding, our data show that fpVCT may be highly suitable for the noninvasive evaluation of tumor responses to anticancer therapies during the course of the disease.

  2. Reducing dose in urography while maintaining image quality - a comparison of storage phosphor plates and a flat-panel detector

    Energy Technology Data Exchange (ETDEWEB)

    Jansson, Margareta; Geijer, Haakan; Andersson, Torbjoern [Oerebro University Hospital, Department of Radiology, Oerebro (Sweden); Persliden, Jan [Oerebro University Hospital, Department of Medical Physics, Oerebro (Sweden); Linkoeping University, Department of Medicine and Care, Faculty of Health Sciences, Linkoeping (Sweden)

    2006-01-01

    The introduction of new flat-panel detector technology often forces us to accept too high dose levels as proposed by the manufacturers. We need a tool to compare the image quality of a new system with the accepted standard. The aim of this study was to obtain a comparable image quality for two systems - storage phosphor plates and a flat-panel system using intravenous urography (IVU) as a clinical model. The image quality figure was calculated using a contrast-detail phantom (CDRAD) for the two evaluated systems. This allowed us to set a dose for the flat-panel system that gave equivalent image quality to the storage phosphor plates. This reduced detector dose was used in an evaluation of clinical images to find out if the dose reduction from the phantom study indeed resulted in images of equal clinical image quality. The image quality was assessed using image criteria of the European guidelines for IVU with visual grading analysis. Equivalent image quality in image pairs was achieved at 30% of the dose. The CDRAD contrast-detail phantom makes it possible to find dose levels that give equal image quality using different imaging systems. (orig.)

  3. Design and performance of the prototype full field breast tomosynthesis system with selenium based flat panel detector

    Science.gov (United States)

    Ren, Baorui; Ruth, Chris; Stein, Jay; Smith, Andrew; Shaw, Ian; Jing, Zhenxue

    2005-04-01

    We have developed a breast tomosynthesis system utilizing a selenium-based direct conversion flat panel detector. This prototype system is a modification of Selenia, Hologic"s full field digital mammography system, using an add-on breast holding device to allow 3D tomosynthetic imaging. During a tomosynthesis scan, the breast is held stationary while the x-ray source and detector mounted on a c-arm rotate continuously around the breast over an angular range up to 30 degrees. The x-ray tube is pulsed to acquire 11 projections at desired c-arm angles. Images are reconstructed in planes parallel to the breastplate using a filtered backprojection algorithm. Processing time is typically 1 minute for a 50 mm thick breast at 0.1 mm in-plane pixel size, 1 mm slice-to-slice separation. Clinical studies are in progress. Performance evaluations were carried out at the system and the subsystem levels including spatial resolution, signal-to-noise ratio, spectra optimization, imaging technique, and phantom and patient studies. Experimental results show that we have successfully built a tomosynthesis system with images showing less structure noise and revealing 3D information compared with the conventional mammogram. We introduce, for the first time, the definition of "Depth of Field" for tomosynthesis based on a spatial resolution study. This parameter is used together with Modulation Transfer Function (MTF) to evaluate 3D resolution of a tomosynthesis system as a function of system design, imaging technique, and reconstruction algorithm. Findings from the on-going clinical studies will help the design of the next generation tomosynthesis system offering improved performance.

  4. Accuracy of chest radiography versus chest computed tomography in hemodynamically stable patients with blunt chest trauma

    Directory of Open Access Journals (Sweden)

    Chardoli Mojtaba

    2013-12-01

    Full Text Available 【Abstract】 Objective: Thoracic injuries are respon- sible for 25% of deaths of blunt traumas. Chest X-ray (CXR is the first diagnostic method in patients with blunt trauma. The aim of this study was to detect the accuracy of CXR versus chest computed tomograpgy (CT in hemodynami- cally stable patients with blunt chest trauma. Methods: Study was conducted at the emergency department of Sina Hospital from March 2011 to March 2012. Hemodynamically stable patients with at least 16 years of age who had blunt chest trauma were included. All patients underwent the same diagnostic protocol which consisted of physical examination, CXR and CT scan respectively. Results: Two hundreds patients (84% male and 16% female were included with a mean age of (37.9±13.7 years. Chin J Traumatol 2013;16(6:351-354 Rib fracture was the most common finding of CXR (12.5% and CT scan (25.5%. The sensitivity of CXR for hemothorax, thoracolumbar vertebra fractures and rib fractures were 20%, 49% and 49%, respectively. Pneumothorax, foreign body, emphysema, pulmonary contusion, liver hematoma and ster- num fracture were not diagnosed with CXR alone. Conclusion: Applying CT scan as the first-line diag- nostic modality in hemodynamically stable patients with blunt chest trauma can detect pathologies which may change management and outcome. Key words: Radiography; Thoracic injuries; Tomography, X-ray computed

  5. Reconstruction of Spectra Using X-ray Flat Panel Detector; Reconstruccion de Espectros de Rayos X Utilizando un Detector Flat Panel

    Energy Technology Data Exchange (ETDEWEB)

    Gallardo, S.; Querol, A.; Pozuelo, F.; Juste, B.; Rodenas, J.; Verdu, G.

    2013-07-01

    In this work, we used a flat panel detector with a wedge of PMMA for absorbed dose curve for given working conditions of X-ray tube The relationship between absorbed dose curve recorded by the flat panel and primary X-ray spectrum is defined by a response function that can be obtained using the Monte Carlo method, namely the MCNP5 code. However there are some problems that affect the applicability of this method such as: flat panel characteristics and the characteristics of the physical process (ill-conditioned problem). Both aspects are discussed in this paper.

  6. Dual-energy cone-beam CT with a flat-panel detector: Effect of reconstruction algorithm on material classification

    Energy Technology Data Exchange (ETDEWEB)

    Zbijewski, W., E-mail: wzbijewski@jhu.edu; Gang, G. J.; Xu, J.; Wang, A. S.; Stayman, J. W. [Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland 21205 (United States); Taguchi, K.; Carrino, J. A. [Russell H. Morgan Department of Radiology, Johns Hopkins University, Baltimore, Maryland 21205 (United States); Siewerdsen, J. H. [Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland 21205 and Russell H. Morgan Department of Radiology, Johns Hopkins University, Baltimore, Maryland 21205 (United States)

    2014-02-15

    Purpose: Cone-beam CT (CBCT) with a flat-panel detector (FPD) is finding application in areas such as breast and musculoskeletal imaging, where dual-energy (DE) capabilities offer potential benefit. The authors investigate the accuracy of material classification in DE CBCT using filtered backprojection (FBP) and penalized likelihood (PL) reconstruction and optimize contrast-enhanced DE CBCT of the joints as a function of dose, material concentration, and detail size. Methods: Phantoms consisting of a 15 cm diameter water cylinder with solid calcium inserts (50–200 mg/ml, 3–28.4 mm diameter) and solid iodine inserts (2–10 mg/ml, 3–28.4 mm diameter), as well as a cadaveric knee with intra-articular injection of iodine were imaged on a CBCT bench with a Varian 4343 FPD. The low energy (LE) beam was 70 kVp (+0.2 mm Cu), and the high energy (HE) beam was 120 kVp (+0.2 mm Cu, +0.5 mm Ag). Total dose (LE+HE) was varied from 3.1 to 15.6 mGy with equal dose allocation. Image-based DE classification involved a nearest distance classifier in the space of LE versus HE attenuation values. Recognizing the differences in noise between LE and HE beams, the LE and HE data were differentially filtered (in FBP) or regularized (in PL). Both a quadratic (PLQ) and a total-variation penalty (PLTV) were investigated for PL. The performance of DE CBCT material discrimination was quantified in terms of voxelwise specificity, sensitivity, and accuracy. Results: Noise in the HE image was primarily responsible for classification errors within the contrast inserts, whereas noise in the LE image mainly influenced classification in the surrounding water. For inserts of diameter 28.4 mm, DE CBCT reconstructions were optimized to maximize the total combined accuracy across the range of calcium and iodine concentrations, yielding values of ∼88% for FBP and PLQ, and ∼95% for PLTV at 3.1 mGy total dose, increasing to ∼95% for FBP and PLQ, and ∼98% for PLTV at 15.6 mGy total dose. For a

  7. Chest radiography and abdominal ultrasound in general practice

    NARCIS (Netherlands)

    Speets, Anouk Mariëlle

    2006-01-01

    Chest radiography (CXR) and abdominal ultrasound (US) are two widely used diagnostic imaging techniques in Western societies. General practitioners (GPs) in The Netherlands annually request approximately 500,000 CXRs and 200,000 abdominal US, and therefore clearly place a burden on health care. Besi

  8. High-quality 3D correction of ring and radiant artifacts in flat panel detector-based cone beam volume CT imaging.

    Science.gov (United States)

    Anas, Emran Mohammad Abu; Kim, Jae Gon; Lee, Soo Yeol; Hasan, Md Kamrul

    2011-10-07

    The use of an x-ray flat panel detector is increasingly becoming popular in 3D cone beam volume CT machines. Due to the deficient semiconductor array manufacturing process, the cone beam projection data are often corrupted by different types of abnormalities, which cause severe ring and radiant artifacts in a cone beam reconstruction image, and as a result, the diagnostic image quality is degraded. In this paper, a novel technique is presented for the correction of error in the 2D cone beam projections due to abnormalities often observed in 2D x-ray flat panel detectors. Template images are derived from the responses of the detector pixels using their statistical properties and then an effective non-causal derivative-based detection algorithm in 2D space is presented for the detection of defective and mis-calibrated detector elements separately. An image inpainting-based 3D correction scheme is proposed for the estimation of responses of defective detector elements, and the responses of the mis-calibrated detector elements are corrected using the normalization technique. For real-time implementation, a simplification of the proposed off-line method is also suggested. Finally, the proposed algorithms are tested using different real cone beam volume CT images and the experimental results demonstrate that the proposed methods can effectively remove ring and radiant artifacts from cone beam volume CT images compared to other reported techniques in the literature.

  9. High-quality 3D correction of ring and radiant artifacts in flat panel detector-based cone beam volume CT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Anas, Emran Mohammad Abu; Hasan, Md Kamrul [Department of Electrical and Electronic Engineering, Bangladesh University of Engineering and Technology, Dhaka-1000 (Bangladesh); Kim, Jae Gon; Lee, Soo Yeol, E-mail: khasan@eee.buet.ac.b [Department of Biomedical Engineering, Kyung Hee University, Kyungki 446-701 (Korea, Republic of)

    2011-10-07

    The use of an x-ray flat panel detector is increasingly becoming popular in 3D cone beam volume CT machines. Due to the deficient semiconductor array manufacturing process, the cone beam projection data are often corrupted by different types of abnormalities, which cause severe ring and radiant artifacts in a cone beam reconstruction image, and as a result, the diagnostic image quality is degraded. In this paper, a novel technique is presented for the correction of error in the 2D cone beam projections due to abnormalities often observed in 2D x-ray flat panel detectors. Template images are derived from the responses of the detector pixels using their statistical properties and then an effective non-causal derivative-based detection algorithm in 2D space is presented for the detection of defective and mis-calibrated detector elements separately. An image inpainting-based 3D correction scheme is proposed for the estimation of responses of defective detector elements, and the responses of the mis-calibrated detector elements are corrected using the normalization technique. For real-time implementation, a simplification of the proposed off-line method is also suggested. Finally, the proposed algorithms are tested using different real cone beam volume CT images and the experimental results demonstrate that the proposed methods can effectively remove ring and radiant artifacts from cone beam volume CT images compared to other reported techniques in the literature.

  10. [Correlation between basic imaging properties and subjective evaluations of two digital radiographic X-ray systems based on direct-conversion flat panel detector].

    Science.gov (United States)

    Sakaguchi, Taro; Katayama, Reiji; Morishita, Junji; Sakai, Shinji; Kuroki, Hidefumi; Ohkubo, Seiji; Maeda, Takashi; Hayabuchi, Naofumi

    2010-11-20

    The purpose of this study was to examine the correlation between the basic imaging properties of two digital radiographic X-ray systems with a direct conversion flat-panel detector and their image qualities, which were evaluated by the observer in hard copy and soft copy studies. The subjective image quality was evaluated and compared in terms of the low-contrast detectability and image sharpness in the two digital radiographic X-ray systems. We applied the radiographs of a contrast detail phantom to the evaluation of low-contrast detectability and analyzed the contrast detail diagrams. Finally, low-contrast detectability was evaluated by the image quality figure (IQF) calculated from the contrast detail diagrams. Also, the subjective image sharpness of human dry bones of two systems was examined and evaluated by the normalized-rank method. The results indicated that System A tended to provide superior subjective image quality compared to System B in both observer studies. We also found high correlations between IQFs and basic imaging properties, such as the noise power spectrum (NPS) and the noise equivalent quantum (NEQ). In conclusion, the low-contrast detectability of the two digital radiographic X-ray systems with a direct conversion flat-panel detector corresponded to the NPS and the NEQ in both outputs (soft copy and hard copy). On the other hand, the subjective image sharpness of human dry bones was affected by their noise properties.

  11. 数字平板探测器的原理及应用%Principle and Application of Flat Panel Detectors

    Institute of Scientific and Technical Information of China (English)

    王建华

    2011-01-01

    Digital radiographic testing is a hot research direction at present, in which the development process of the digital detector will determine the development direction of digital radiographic testing. The developing history, structure, imaging process, image quality and application advantages of digital flat panel detector were described. By the practical measurement, it was confirmed that flat-panel detector test was expected to replace traditional film imaging and image intensifier mode, and it showed a very broad application prospects.%数字射线检测是当前射线检测的热点研究方向,其中探测器的发展进程直接决定了数字射线检测的发展方向。介绍了目前应用较广的平板探测器的发展历史、平板结构、成像过程、成像质量以及应用优势等。通过实测试验,证实了平板探测器有望取代传统的胶片成像以及图像增强器方式成像,应用前景非常广阔。

  12. Computer-aided diagnosis in chest radiography: Beyond nodules

    Energy Technology Data Exchange (ETDEWEB)

    Ginneken, Bram van [University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht (Netherlands)], E-mail: bram@isi.uu.nl; Hogeweg, Laurens; Prokop, Mathias [University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht (Netherlands)

    2009-11-15

    Chest radiographs are the most common exam in radiology. They are essential for the management of various diseases associated with high mortality and morbidity and display a wide range of findings, many of them subtle. In this survey we identify a number of areas beyond pulmonary nodules that could benefit from computer-aided detection and diagnosis (CAD) in chest radiography. These include interstitial infiltrates, catheter tip detection, size measurements, detection of pneumothorax and detection and quantification of emphysema. Recent work in these areas is surveyed, but we conclude that the amount of research devoted to these topics is modest. Reasons for the slow pace of CAD development in chest radiography beyond nodules are discussed.

  13. Dose Reduction to the Thyroid Gland in Pediatric Chest Radiography

    Directory of Open Access Journals (Sweden)

    Vahid Karami

    2016-07-01

    Full Text Available Background  It is remain a main concern that pediatric chest radiographies contribute to the significant radiation exposure to the thyroid gland as a more susceptible organ to radiation induced cancer. The aim of this study was to evaluate the entrance surface dose (ESD of pediatric chest radiography compared to the diagnostic reference levels (DRL and evaluation the efficacy of the lead (Pb shield in radiation dose reduction to the thyroid gland.Materials and Methods After assessing each patient against specific inclusion-exclusion criteria, 40 pediatric patients who were undergoing anterior-posterior (AP projection of the chest x-ray were considered eligible for this study. The ESD of the chest and also ESD of thyroid gland with and without a 1 mm butterfly-shaped lead shield which placed on the thyroid gland were measured using high sensitive thermo luminescent dosimeters (TLD-GR 200.Results The average of ESD for chest radiography was 0.068+ 0.006 mGy (0.021 - 0.232 mGy. The unshielded average thyroid ESD was 0.065 + 0.003 mGy compared to the shielded average thyroid ESD of 0.001 + 0.0005 mGy. The use of Pb-shield produced a statistically significant decrease in the average thyroid dose by about 97% (P< 0.001. Conclusion The use of Pb-thyroid shield in the AP projection of pediatric chest radiography has potential to reduced radiation dose without compromising image quality.

  14. Chest radiography in the critically ill

    NARCIS (Netherlands)

    Kröner, A.

    2016-01-01

    Introduction: The chest radiograph (CXR) is a frequently obtained test to complement physical examination in ICU and post-surgery PACU patients. The opinion on indications for a CXR in these two patient categories varies worldwide. One approach is to obtain CXR on indication only, i.e., when there i

  15. CCD digital radiography system

    Science.gov (United States)

    Wang, Yi; Kang, Xi; Li, Yuanjing; Cheng, Jianping; Hou, Yafei; Han, Haiwei

    2009-07-01

    Amorphous silicon flat-panel detector is the mainstream used in digital radiography (DR) system. In latest years, scintillation screen coupled with CCD DR is becoming more popular in hospital. Compared with traditional amorphous silicon DR, CCD-DR has better spatial resolution and has little radiation damage. It is inexpensive and can be operated easily. In this paper, A kind of CCD based DR system is developed. We describe the construction of the system, the system performances and experiment results.

  16. A Ring Artifact Correction Method: Validation by Micro-CT Imaging with Flat-Panel Detectors and a 2D Photon-Counting Detector

    Directory of Open Access Journals (Sweden)

    Mohamed Elsayed Eldib

    2017-01-01

    Full Text Available We introduce an efficient ring artifact correction method for a cone-beam computed tomography (CT. In the first step, we correct the defective pixels whose values are close to zero or saturated in the projection domain. In the second step, we compute the mean value at each detector element along the view angle in the sinogram to obtain the one-dimensional (1D mean vector, and we then compute the 1D correction vector by taking inverse of the mean vector. We multiply the correction vector with the sinogram row by row over all view angles. In the third step, we apply a Gaussian filter on the difference image between the original CT image and the corrected CT image obtained in the previous step. The filtered difference image is added to the corrected CT image to compensate the possible contrast anomaly that may appear due to the contrast change in the sinogram after removing stripe artifacts. We applied the proposed method to the projection data acquired by two flat-panel detectors (FPDs and a silicon-based photon-counting X-ray detector (PCXD. Micro-CT imaging experiments of phantoms and a small animal have shown that the proposed method can greatly reduce ring artifacts regardless of detector types. Despite the great reduction of ring artifacts, the proposed method does not compromise the original spatial resolution and contrast.

  17. AAPM/RSNA physics tutorial for residents: physics of flat-panel fluoroscopy systems: Survey of modern fluoroscopy imaging: flat-panel detectors versus image intensifiers and more.

    Science.gov (United States)

    Nickoloff, Edward Lee

    2011-01-01

    This article reviews the design and operation of both flat-panel detector (FPD) and image intensifier fluoroscopy systems. The different components of each imaging chain and their functions are explained and compared. FPD systems have multiple advantages such as a smaller size, extended dynamic range, no spatial distortion, and greater stability. However, FPD systems typically have the same spatial resolution for all fields of view (FOVs) and are prone to ghosting. Image intensifier systems have better spatial resolution with the use of smaller FOVs (magnification modes) and tend to be less expensive. However, the spatial resolution of image intensifier systems is limited by the television system to which they are coupled. Moreover, image intensifier systems are degraded by glare, vignetting, spatial distortions, and defocusing effects. FPD systems do not have these problems. Some recent innovations to fluoroscopy systems include automated filtration, pulsed fluoroscopy, automatic positioning, dose-area product meters, and improved automatic dose rate control programs. Operator-selectable features may affect both the patient radiation dose and image quality; these selectable features include dose level setting, the FOV employed, fluoroscopic pulse rates, geometric factors, display software settings, and methods to reduce the imaging time.

  18. Reducing dose in urography while maintaining image quality-a comparison of storage phosphor plates and a flat-panel detector.

    Science.gov (United States)

    Jansson, Margareta; Geijer, Håkan; Persliden, Jan; Andersson, Torbjörn

    2006-01-01

    The introduction of new flat-panel detector technology often forces us to accept too high dose levels as proposed by the manufacturers. We need a tool to compare the image quality of a new system with the accepted standard. The aim of this study was to obtain a comparable image quality for two systems-storage phosphor plates and a flat-panel system using intravenous urography (IVU) as a clinical model. The image quality figure was calculated using a contrast-detail phantom (CDRAD) for the two evaluated systems. This allowed us to set a dose for the flat-panel system that gave equivalent image quality to the storage phosphor plates. This reduced detector dose was used in an evaluation of clinical images to find out if the dose reduction from the phantom study indeed resulted in images of equal clinical image quality. The image quality was assessed using image criteria of the European guidelines for IVU with visual grading analysis. Equivalent image quality in image pairs was achieved at 30% of the dose. The CDRAD contrast-detail phantom makes it possible to find dose levels that give equal image quality using different imaging systems.

  19. A Ring Artifact Correction Method: Validation by Micro-CT Imaging with Flat-Panel Detectors and a 2D Photon-Counting Detector

    Science.gov (United States)

    Eldib, Mohamed Elsayed; Hegazy, Mohamed; Mun, Yang Ji; Cho, Myung Hye; Cho, Min Hyoung; Lee, Soo Yeol

    2017-01-01

    We introduce an efficient ring artifact correction method for a cone-beam computed tomography (CT). In the first step, we correct the defective pixels whose values are close to zero or saturated in the projection domain. In the second step, we compute the mean value at each detector element along the view angle in the sinogram to obtain the one-dimensional (1D) mean vector, and we then compute the 1D correction vector by taking inverse of the mean vector. We multiply the correction vector with the sinogram row by row over all view angles. In the third step, we apply a Gaussian filter on the difference image between the original CT image and the corrected CT image obtained in the previous step. The filtered difference image is added to the corrected CT image to compensate the possible contrast anomaly that may appear due to the contrast change in the sinogram after removing stripe artifacts. We applied the proposed method to the projection data acquired by two flat-panel detectors (FPDs) and a silicon-based photon-counting X-ray detector (PCXD). Micro-CT imaging experiments of phantoms and a small animal have shown that the proposed method can greatly reduce ring artifacts regardless of detector types. Despite the great reduction of ring artifacts, the proposed method does not compromise the original spatial resolution and contrast. PMID:28146088

  20. A method to optimize the processing algorithm of a computed radiography system for chest radiography.

    Science.gov (United States)

    Moore, C S; Liney, G P; Beavis, A W; Saunderson, J R

    2007-09-01

    A test methodology using an anthropomorphic-equivalent chest phantom is described for the optimization of the Agfa computed radiography "MUSICA" processing algorithm for chest radiography. The contrast-to-noise ratio (CNR) in the lung, heart and diaphragm regions of the phantom, and the "system modulation transfer function" (sMTF) in the lung region, were measured using test tools embedded in the phantom. Using these parameters the MUSICA processing algorithm was optimized with respect to low-contrast detectability and spatial resolution. Two optimum "MUSICA parameter sets" were derived respectively for maximizing the CNR and sMTF in each region of the phantom. Further work is required to find the relative importance of low-contrast detectability and spatial resolution in chest images, from which the definitive optimum MUSICA parameter set can then be derived. Prior to this further work, a compromised optimum MUSICA parameter set was applied to a range of clinical images. A group of experienced image evaluators scored these images alongside images produced from the same radiographs using the MUSICA parameter set in clinical use at the time. The compromised optimum MUSICA parameter set was shown to produce measurably better images.

  1. Performance analysis of a CsI-based flat panel detector in a cone beam variable resolution x-ray system

    Science.gov (United States)

    Dahi, Bahram; Keyes, Gary S.; Rendon, David A.; DiBianca, Frank A.

    2007-03-01

    A new Cone-Beam CT (CBCT) system is introduced that uses the concept of Variable Resolution X-ray (VRX) detection, which has previously been demonstrated to significantly increase spatial resolution for small objects. An amorphous silicon Flat Panel Detector (FPD) with a CsI scintillator (PaxScan 2020, Varian, Salt Lake City, UT) is coupled with a micro-focus x-ray tube (35 - 80 kVp, 10 - 250 μA) to form a CBCT. The FPD is installed on a rotating arm that can be adjusted to any angle θ, called the VRX angle, between 90° and 0° with respect to the x-ray direction. A VRX angle of 90° for the detector corresponds to a conventional CBCT whereas a VRX angle of 30° means that the detector is tilted 90° - 30° = 60° from its perpendicular position. Tilting the FPD in this manner reduces both the line-spread function width and the sampling distance by a factor of sin(θ), thereby increasing detector spatial resolution proportionately. An in-house phantom is used to measure the MTF of the reconstructed CT images using different VRX angles. An increase by a factor of 1.67 +/- 0.007 is observed in the MTF cutoff frequency at 30° compared to 90° in images acquired at 75 kVp. Expected theoretical value for this case is 2.0. The new Cone-Beam Variable Resolution X-ray (CB-VRX) CT system is expected to significantly improve the images acquired from small objects - such as small animals - while exploiting the opportunities offered by a conventional CBCT.

  2. Effect of x-ray incident direction and scintillator layer design on image quality of indirect-conversion flat-panel detector with GOS phosphor

    Science.gov (United States)

    Sato, K.; Nariyuki, F.; Nomura, H.; Takasu, A.; Fukui, S.; Nakatsu, M.; Okada, Y.; Nabeta, T.; Hosoi, Y.

    2011-03-01

    In this study, we characterized the image quality of two types of indirect-conversion flat-panel detectors: an X-ray incident-side photo-detection system (IS) and an X-ray penetration-side photo-detection system (PS). These detectors consist of a Gd2O2S:Tb (GOS) scintillator coupled with a photodiode thin film transistor (PD-TFT) array on a glass substrate. The detectors have different X-ray incident directions, glass substrates, and scintillators. We also characterized the effects of layered scintillator structures on the image quality by using a single-layered scintillator containing large phosphor grains and a double-layered scintillator consisting of a layer of large phosphor grains and a layer of small phosphor grains. The IS system consistently demonstrated a higher MTF than the PS system for a scintillator of the same thickness. Moreover, the IS system showed a higher DQE than the PS system when a thick scintillator was used. While the double-layered scintillators were useful for improving the MTF in both systems, a thick single-layered scintillator was preferable for obtaining a high DQE when the IS system was applied. These results indicate that an IS system can efficiently utilize the light emitted from the phosphor at the far side of the PD without the occurrence of blurring. The use of IS systems makes it possible to increase the thickness of the scintillator layer for improving the sensitivity without reducing the MTF, which increases the DQE. The DQE of the IS system was 1.2 times that of the PS system, despite the absorption of X-rays at the glass substrate before entering the phosphor.

  3. Quantitative comparison using generalized relative object detectability (G-ROD) metrics of an amorphous selenium detector with high resolution microangiographic fluoroscopes (MAF) and standard flat panel detectors (FPD)

    Science.gov (United States)

    Russ, M.; Shankar, A.; Jain, A.; Setlur Nagesh, S. V.; Ionita, C. N.; Scott, C.; Karim, K. S.; Bednarek, D. R.; Rudin, S.

    2016-03-01

    A novel amorphous selenium (a-Se) direct detector with CMOS readout has been designed, and relative detector performance investigated. The detector features include a 25μm pixel pitch, and 1000μm thick a-Se layer operating at 10V/μm bias field. A simulated detector DQE was determined, and used in comparative calculations of the Relative Object Detectability (ROD) family of prewhitening matched-filter (PWMF) observer and non-pre-whitening matched filter (NPWMF) observer model metrics to gauge a-Se detector performance against existing high resolution micro-angiographic fluoroscopic (MAF) detectors and a standard flat panel detector (FPD). The PWMF-ROD or ROD metric compares two x-ray imaging detectors in their relative abilities in imaging a given object by taking the integral over spatial frequencies of the Fourier transform of the detector DQE weighted by an object function, divided by the comparable integral for a different detector. The generalized-ROD (G-ROD) metric incorporates clinically relevant parameters (focal- spot size, magnification, and scatter) to show the degradation in imaging performance for detectors that are part of an imaging chain. Preliminary ROD calculations using simulated spheres as the object predicted superior imaging performance by the a-Se detector as compared to existing detectors. New PWMF-G-ROD and NPWMF-G-ROD results still indicate better performance by the a-Se detector in an imaging chain over all sphere sizes for various focal spot sizes and magnifications, although a-Se performance advantages were degraded by focal spot blurring. Nevertheless, the a-Se technology has great potential to provide break- through abilities such as visualization of fine details including of neuro-vascular perforator vessels and of small vascular devices.

  4. Clinical evaluation of flat-panel detector compared with multislice computed tomography in 65 patients with acute intracranial hemorrhage: initial results. Clinical article.

    Science.gov (United States)

    Struffert, Tobias; Eyupoglu, Ilker Y; Huttner, Hagen B; Engelhorn, Tobias; Doelken, Marc; Saake, Marc; Ganslandt, Oliver; Doerfler, Arnd

    2010-10-01

    The goal in this study was to compare flat-panel detector (FD) CT with multislice (MS) CT in the visualization of intracerebral hemorrhage (ICH), subarachnoid hemorrhage (SAH), intraventricular hemorrhage, and external ventricular drains (EVDs) to evaluate the diagnostic quality and limitations of the new FD CT imaging modality. Neuroimages obtained in 65 patients, including 24 with EVDs, were reviewed by 2 independent, experienced clinicians. Lesions in all patients were investigated with FD CT and MS CT. The numbers of slices positive for ICH and SAH were counted, and for ICH the diameter and area of the lesion was measured. The positioning of drains was assessed. The presence of ventricular blood was noted. Statistical analysis was performed by calculating the Pearson correlation coefficient (r) to evaluate the level of inter- and intraobserver agreement, and linear regression analysis was done to visualize the results of the numbers of ICH- and SAH-positive slices. The authors found high interobserver agreement regarding the number of slices with evidence of ICH (r = 0.89 for MS CT, r = 0.78 for FD CT) and SAH (r = 0.88 for MS CT, r = 0.9 for FD CT). Thin layers of blood in the ventricles were not detected on FD CT in 36.4% of cases. Six of 7 perimesencephalic SAHs were not seen on FD CT scans. The EVDs could be assessed with both modalities in 83.3% of cases, but the position of the drain could not be determined with FD CT in 16.7% (4 of 24 cases). In some respects, FD CT is of limited use for the visualization of intracranial hemorrhage. However, despite limited contrast resolution, ICH and EVDs can be reliably demonstrated. Perimesencephalic SAH and thin layers of blood in the occipital horns may not be detected using FD CT. Further evaluation and improvement of the image quality is necessary before FD CT will provide identical quality in comparison with MS CT.

  5. Radiation doses to operators performing transjugular intrahepatic portosystemic shunt using a flat-panel detector-based system and ultrasound guidance for portal vein targeting.

    Science.gov (United States)

    Miraglia, Roberto; Gerasia, Roberta; Maruzzelli, Luigi; D'Amico, Mario; Luca, Angelo

    2017-05-01

    The aim of this study was to prospectively evaluate effective dose (E) of operators performing transjugular intrahepatic portosystemic shunts (TIPS) in a single centre. Patients' radiation exposure was also collected. Between 8/2015 and 6/2016, 45 consecutive TIPS were performed in adult patients using a flat-panel detector-based system (FPDS) and real-time ultrasound guidance (USG) for portal vein targeting. Electronic personal dosimeters were used to measure radiation doses to the primary and assistant operators, anaesthesia nurse and radiographer. Patients' radiation exposure was measured with dose area product (DAP); fluoroscopy time (FT) was also collected. Mean E for the primary operator was 1.40 μSv (SD 2.68, median 0.42, range 0.12 - 12.18), for the assistant operator was 1.29 μSv (SD 1.79, median 0.40, range 0.10 - 4.89), for the anaesthesia nurse was 0.21 μSv (SD 0.67, median 0.10, range 0.03 - 3.99), for the radiographer was 0.42 μSv (SD 0.71, median 0.25, range 0.03 - 2.67). Mean patient DAP was 59.31 GyCm(2) (SD 56.91, median 31.58, range 7.66 - 281.40); mean FT was 10.20 min (SD 7.40, median 10.40, range 3.8 - 31.8). The use of FPDS and USG for portal vein targeting allows a reasonably low E to operators performing TIPS. • The operators' E vary according to the complexity of the procedure. • FPDS and USG allow a reasonably low E to TIPS operators. • FPDS and USG have an important role in reducing the occupational exposure.

  6. Cone-beam CT with a flat-panel detector on a mobile C-arm: preclinical investigation in image-guided surgery of the head and neck

    Science.gov (United States)

    Siewerdsen, J. H.; Chan, Y.; Rafferty, M. A.; Moseley, D. J.; Jaffray, D. A.; Irish, J. C.

    2005-04-01

    A promising imaging platform for combined low-dose fluoroscopy and cone-beam CT (CBCT) guidance of interventional procedures has been developed in our laboratory. Based on a mobile isocentric C-arm (Siemens PowerMobil) incorporating a high-performance flat-panel detector (Varian PaxScan 4030CB), the system demonstrates sub-mm 3D spatial resolution and soft-tissue visibility with field of view sufficient for head and body sites. For pre-clinical studies in head neck tumor surgery, we hypothesize that the 3D intraoperative information provided by CBCT permits precise, aggressive techniques with improved avoidance of critical structures. The objectives include: 1) quantify improvement in surgical performance achieved with CBCT guidance compared to open and endoscopic techniques; and 2) investigate specific, challenging surgical tasks under CBCT guidance. Investigations proceed from an idealized phantom model to cadaveric specimens. A novel surgical performance evaluation method based on statistical decision theory is applied to excision and avoidance tasks. Analogous to receiver operating characteristic (ROC) analysis in medical imaging, the method quantifies surgical performance in terms of Lesion-Excised (True-Positve), Lesion-Remaining (False-Negative), Normal-Excised (False-Positive), and Normal-Remaining (True-Negative) fractions. Conservative and aggressive excision and avoidance tasks are executed in 12 cadaveric specimens with and without CBCT guidance, including: dissection through dura, preservation of posterior lamina, ethmoid air cells removal, exposure of peri-orbita, and excision of infiltrated bone in the skull base (clivus). Intraoperative CBCT data was found to dramatically improve surgical performance and confidence in the execution of such tasks. Pre-clinical investigation of this platform in head and neck surgery, as well as spinal, trauma, biopsy, and other nonvascular procedures, is discussed.

  7. Impact of chest radiography for children with lower respiratory tract infection: a propensity score approach.

    Directory of Open Access Journals (Sweden)

    Emmanuelle Ecochard-Dugelay

    Full Text Available BACKGROUND: Management of acute respiratory tract infection varies substantially despite this being a condition frequently encountered in pediatric emergency departments. Previous studies have suggested that the use of antibiotics was higher when chest radiography was performed. However none of these analyses had considered the inherent indication bias of observational studies. OBJECTIVE: The aim of this work was to assess the relationship between performing chest radiography and prescribing antibiotics using a propensity score analysis to address the indication bias due to non-random radiography assignment. METHODS: We conducted a prospective study of 697 children younger than 2 years of age who presented during the winter months of 2006-2007 for suspicion of respiratory tract infection at the Pediatric Emergency Department of an urban general hospital in France (Paris suburb. We first determined the individual propensity score (probability of having a chest radiography according to baseline characteristics. Then we assessed the relation between radiography and antibiotic prescription using two methods: adjustment and matching on the propensity score. RESULTS: We found that performing a chest radiography lead to more frequent antibiotic prescription that may be expressed as OR = 2.3, CI [1.3-4.1], or as an increased use of antibiotics of 18.6% [0.08-0.29] in the group undergoing chest radiography. CONCLUSION: Chest radiography has a significant impact on the management of infants admitted for suspicion of respiratory tract infection in a pediatric emergency department and may lead to unnecessary administration of antibiotics.

  8. Optimisation of computed radiography systems for chest imaging

    Energy Technology Data Exchange (ETDEWEB)

    Alzimami, K. [Department of Physics, University of Surrey, Guildford, Surrey GU2 7XH (United Kingdom)], E-mail: k.alzimami@surrey.ac.uk; Sassi, S. [Royal Marsden NHS Foundation Trust, Sutton, Surrey SM2 5PT (United Kingdom); Alkhorayef, M. [Department of Physics, University of Surrey, Guildford, Surrey GU2 7XH (United Kingdom); Britten, A.J. [Department of Medical Physics, St George' s Hospital, London SW17 0QT (United Kingdom); Spyrou, N.M. [Department of Physics, University of Surrey, Guildford, Surrey GU2 7XH (United Kingdom)

    2009-03-01

    The main thrust of this study is to investigate methods of optimising the radiation dose-image quality relationship in computed radiography (CR) systems for chest imaging. Specifically, this study investigates the possibility of reducing the patient radiation exposure through an optimal selection of tube filtration, exposure parameters and air gap technique, in parallel with a study of the image quality, particularly low contrast detail detectability, signal-to-noise ratio (SNR) and scatter fraction (SF). The CDRAD phantom was used to assess the quality of the CR images. Tissue equivalent Polystyrene blocks were placed in the front of the phantom as scattering material with thicknesses of 5 and 15 cm to simulate an adult chest and heart/diaphragm regions, respectively. A series of exposure techniques were used, including Cu filtration with various thicknesses of Cu in the presence and absence of an air gap, whilst the exposure was kept as constant as possible throughout. The estimated patient effective dose and skin entrance dose were calculated using the NRPB-SR262 X-ray dose calculation software. The results have shown that the low contrast-detail detectability in the lung and the heart/diaphragm regions improves when using an air gap and no Cu filtration, particularly at low kilovoltage (kVp). However, there is no significant difference in low contrast-detail in the absence or presence of a 0.2 mm Cu filtration. SF values for the lung and heart regions decrease when using both, the air gap technique and a 0.2 mm Cu filtration, particularly at low kVp. SNR values for the lung and heart regions improve when using a small Cu thickness. In conclusion, this investigation has shown that the quality of chest CR images could be improved by using an air gap technique and a 0.2 mm Cu filtration at low kVp, particularly at 99 kVp.

  9. Accuracy of chest radiography versus chest computed tomography in hemodynamically stable patients with blunt chest trauma

    Institute of Scientific and Technical Information of China (English)

    Mojtaba Chardoli; Toktam Hasan-Ghaliaee; Hesam Akbari; Vafa Rahimi-Movaghar

    2013-01-01

    Objective:Thoracic injuries are responsible for 25% of deaths of blunt traumas.Chest X-ray (CXR) is the first diagnostic method in patients with blunt trauma.The aim of this study was to detect the accuracy of CXR versus chest computed tomograpgy (CT) in hemodynamically stable patients with blunt chest trauma.Methods:Study was conducted at the emergency department of S ina Hospital from March 2011 to March 2012.Hemodynamically stable patients with at least 16 years of age who had blunt chest trauma were included.All patients underwent the same diagnostic protocol which consisted of physical examination,CXR and CT scan respectively.Results:Two hundreds patients (84% male and 16% female) were included with a mean age of(37.9±13.7) years.Rib fracture was the most common finding of CXR (12.5%) and CT scan (25.5%).The sensitivity of CXR for hemothorax,thoracolumbar vertebra fractures and rib fractures were 20%,49% and 49%,respectively.Pneumothorax,foreign body,emphysema,pulmonary contusion,liver hematoma and sternum fracture were not diagnosed with CXR alone.Conclusion:Applying CT scan as the first-line diagnostic modality in hemodynamically stable patients with blunt chest trauma can detect pathologies which may change management and outcome.

  10. Comparison of the image quality of a high-resolution screen-film system and a digital flat panel detector system in avian radiography.

    Science.gov (United States)

    Bochmann, Monika; Ludewig, Eberhard; Krautwald-Junghanns, Maria-Elisabeth; Pees, Michael

    2011-01-01

    A conventional high-resolution screen-film system was compared with a digital detector system. A total of 20 birds (14 pigeons and six psittacine birds) with an average body mass of 533g were examined in dorsoventral as well as lateral projections. Digital radiographs were acquired with the same mAs as well as half the mAs used for the conventional radiographs. Three criteria and one overall assessment were defined for each of four anatomic regions and assessed by five veterinarians using a score system. Comparison of the ratings was done by visual grading analysis. For the majority of criteria, there was no significant difference regarding image quality between the digital and screen-film projections. However, for certain criteria the quality of the digital images was significantly superior. Using the same mAs as for the conventional radiographs, the humeral joint surfaces and the honeycomb structure of the lung were assessed as superior with the digital imaging system. The tracheal rings and the delineation of the trachea from the surrounding tissue were also superior with the digital system. Assessment of the trabecular structure of the humerus was superior when the full mAs was used compared with the reduced mAs. In conclusion the digital technique is equal or superior to the conventional screen-film high-resolution system for pet birds of a medium size. With some limitations, a dose reduction is possible with the digital system.

  11. A method for verification of treatment delivery in HDR prostate brachytherapy using a flat panel detector for both imaging and source tracking

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Ryan L., E-mail: ryan.smith@wbrc.org.au; Millar, Jeremy L.; Franich, Rick D. [Alfred Health Radiation Oncology, The Alfred Hospital, Melbourne, VIC 3004, Australia and School of Science, RMIT University, Melbourne, VIC 3000 (Australia); Haworth, Annette [School of Science, RMIT University, Melbourne, VIC 3000, Australia and Physical Sciences, Peter MacCallum Cancer Centre, East Melbourne, VIC 3002 (Australia); Panettieri, Vanessa [Alfred Health Radiation Oncology, The Alfred Hospital, Melbourne, VIC 3004 (Australia)

    2016-05-15

    Purpose: Verification of high dose rate (HDR) brachytherapy treatment delivery is an important step, but is generally difficult to achieve. A technique is required to monitor the treatment as it is delivered, allowing comparison with the treatment plan and error detection. In this work, we demonstrate a method for monitoring the treatment as it is delivered and directly comparing the delivered treatment with the treatment plan in the clinical workspace. This treatment verification system is based on a flat panel detector (FPD) used for both pre-treatment imaging and source tracking. Methods: A phantom study was conducted to establish the resolution and precision of the system. A pretreatment radiograph of a phantom containing brachytherapy catheters is acquired and registration between the measurement and treatment planning system (TPS) is performed using implanted fiducial markers. The measured catheter paths immediately prior to treatment were then compared with the plan. During treatment delivery, the position of the {sup 192}Ir source is determined at each dwell position by measuring the exit radiation with the FPD and directly compared to the planned source dwell positions. Results: The registration between the two corresponding sets of fiducial markers in the TPS and radiograph yielded a registration error (residual) of 1.0 mm. The measured catheter paths agreed with the planned catheter paths on average to within 0.5 mm. The source positions measured with the FPD matched the planned source positions for all dwells on average within 0.6 mm (s.d. 0.3, min. 0.1, max. 1.4 mm). Conclusions: We have demonstrated a method for directly comparing the treatment plan with the delivered treatment that can be easily implemented in the clinical workspace. Pretreatment imaging was performed, enabling visualization of the implant before treatment delivery and identification of possible catheter displacement. Treatment delivery verification was performed by measuring the

  12. Evaluation of entrance surface air kerma in pediatric chest radiography

    Science.gov (United States)

    Porto, L.; Lunelli, N.; Paschuk, S.; Oliveira, A.; Ferreira, J. L.; Schelin, H.; Miguel, C.; Denyak, V.; Kmiecik, C.; Tilly, J.; Khoury, H.

    2014-11-01

    The objective of this study was to evaluate the entrance surface air kerma in pediatric chest radiography. An evaluation of 301 radiographical examinations in anterior-posterior (AP) and posterior-anterior (PA) (166 examinations) and lateral (LAT) (135 examinations) projections was performed. The analyses were performed on patients grouped by age; the groups included ages 0-1 y, 1-5 y, 5-10 y, and 10-15 y. The entrance surface air kerma was determined with DoseCal software (Radiological Protection Center of Saint George's Hospital, London) and thermoluminescent dosimeters. Two different exposure techniques were compared. The doses received by patients who had undergone LAT examinations were 40% higher, on average, those in AP/PA examinations because of the difference in tube voltage. A large high-dose “tail” was observed for children up to 5 y old. An increase in tube potential and corresponding decrease in current lead to a significant dose reduction. The difference between the average dose values for different age ranges was not practically observed, implying that the exposure techniques are still not optimal. Exposure doses received using the higher tube voltage and lower current-time product correspond to the international diagnostic reference levels.

  13. Computerized method to compensate for breathing body motion in dynamic chest radiographs

    Science.gov (United States)

    Matsuda, H.; Tanaka, R.; Sanada, S.

    2017-03-01

    Dynamic chest radiography combined with computer analysis allows quantitative analyses on pulmonary function and rib motion. The accuracy of kinematic analysis is directly linked to diagnostic accuracy, and thus body motion compensation is a major concern. Our purpose in this study was to develop a computerized method to reduce a breathing body motion in dynamic chest radiographs. Dynamic chest radiographs of 56 patients were obtained using a dynamic flat-panel detector. The images were divided into a 1 cm-square and the squares on body counter were used to detect the body motion. Velocity vector was measured using cross-correlation method on the body counter and the body motion was then determined on the basis of the summation of motion vector. The body motion was then compensated by shifting the images based on the measured vector. By using our method, the body motion was accurately detected by the order of a few pixels in clinical cases, mean 82.5% in right and left directions. In addition, our method detected slight body motion which was not able to be identified by human observations. We confirmed our method effectively worked in kinetic analysis of rib motion. The present method would be useful for the reduction of a breathing body motion in dynamic chest radiography.

  14. Chest radiography practice in critically ill patients: a postal survey in the Netherlands

    Directory of Open Access Journals (Sweden)

    Korevaar Johanna C

    2006-07-01

    Full Text Available Abstract Background To ascertain current chest radiography practice in intensive care units (ICUs in the Netherlands. Methods Postal survey: a questionnaire was sent to all ICUs with > 5 beds suitable for mechanical ventilation; pediatric ICUs were excluded. When an ICU performed daily-routine chest radiographs in any group of patients it was considered to be a "daily-routine chest radiography" ICU. Results From the number of ICUs responding, 63% practice a daily-routine strategy, in which chest radiographs are obtained on a daily basis without any specific reason. A daily-routine chest radiography strategy is practiced less frequently in university-affiliated ICUs (50% as compared to other ICUs (68%, as well as in larger ICUs (> 20 beds, 50% as compared to smaller ICUs (P > 0.05. Remarkably, physicians that practice a daily-routine strategy consider daily-routine radiographs helpful in guiding daily practice in less than 30% of all performed radiographs. Chest radiographs are considered essential for verification of the position of invasive devices (81% and for diagnosing pneumothorax, pneumonia or acute respiratory distress syndrome (82%, 74% and 69%, respectively. On demand chest radiographs are obtained after introduction of thoracic drains, central venous lines and endotracheal tubes in 98%, 84% and 75% of responding ICUs, respectively. Chest films are also obtained in case of ventilatory deterioration (49% of responding ICUs, and after cardiopulmonary resuscitation (59%, tracheotomy (58% and mini-tracheotomy (23%. Conclusion There is notable lack of consensus on chest radiography practice in the Netherlands. This survey suggests that a large number of intensivists may doubt the value of daily-routine chest radiography, but still practice a daily-routine strategy.

  15. Comparison of image quality and radiation dose between an image-intensifier system and a newer-generation flat-panel detector system - technical phantom measurements and evaluation of clinical imaging in children

    Energy Technology Data Exchange (ETDEWEB)

    Weis, Meike; Hagelstein, Claudia; Diehm, Theo; Schoenberg, Stefan O.; Neff, K.W. [University Center Mannheim, Medical Faculty Mannheim, Heidelberg University, Institute of Clinical Radiology and Nuclear Medicine, Mannheim (Germany)

    2016-02-15

    Many image-intensifier fluoroscopy systems have been replaced by flat-panel detectors in recent years. To compare the level of contrast, image resolution and radiation dose between an image-intensifier and a newer-generation flat-panel detector system in a pediatric radiology unit. We compared two systems - a conventional image intensifier and a newer-generation flat-panel system. We measured image quality and radiation dose using a technical phantom. Additionally, we retrospectively compared age-matched fluoroscopic pediatric voiding cystourethrography (n = 15) and upper gastrointestinal investigations (n = 25). In phantom studies image contrast was equal while image resolution was higher and mean radiation dose lower using the flat-panel system (P < 0.0001). In pediatric investigations, mean dose area product was significantly reduced on the flat-panel system for upper gastrointestinal investigation (45 ± 38 μGy*m{sup 2} vs. 11 ± 9 μGy*m{sup 2}; P < 0.0001) and for voiding cystourethrography (18 ± 20 μGy*m{sup 2} vs. 10 ± 12 μGy*m{sup 2}; P = 0.04). The newer flat-panel system performs at lower dose levels with equal to better image quality and therefore seems to be the more suitable technique for pediatric fluoroscopy in comparison to image-intensifier systems. (orig.)

  16. No Value for Routine Chest Radiography in the Work-Up of Early Stage Cervical Cancer Patients

    NARCIS (Netherlands)

    Hoogendam, Jacob P.; Zweemer, Ronald P.; Verkooijen, Helena M.; de Jong, Pim A.; van den Bosch, Maurice A. A. J.; Verheijen, Rene H. M.; Veldhuis, WB

    2015-01-01

    Aim Evidence supporting the recommendation to include chest radiography in the work-up of all cervical cancer patients is limited. We investigated the diagnostic value of routine chest radiography in cervical cancer staging. Methods All consecutive cervical cancer patients who presented at our terti

  17. Computed and conventional chest radiography: a comparison of image quality and radiation dose.

    Science.gov (United States)

    Ramli, K; Abdullah, B J J; Ng, K-H; Mahmud, R; Hussain, A F

    2005-12-01

    The aim of this study was to compare the image quality and entrance skin dose (ESD) for film-screen and computed chest radiography. Analysis of the image quality and dose on chest radiography was carried out on a conventional X-ray unit using film-screen, storage phosphor plates and selenium drum direct chest radiography. For each receptor, ESD was measured in 60 patients using thermoluminescent dosemeters. Images were printed on 35 x 43 cm films. Image quality was assessed subjectively by evaluation of anatomic features and estimation of the image quality, following the guidelines established by the protocols of the Commission of the European Communities. There was no statistically significant difference noted between the computed and conventional images (Wilcoxon rank sum test, P > 0.05). Imaging of the mediastinum and peripheral lung structures were better visualized with the storage phosphor and selenium drum technique than with the film-screen combination. The patients' mean ESD for chest radiography using the storage phosphor, film-screen combination and selenium drum was 0.20, 0.20 and 0.25 mGy, respectively, with no statistically significant difference with P > 0.05 (chi(2) tests).

  18. First experience with x-ray dark-field radiography for human chest imaging (Conference Presentation)

    Science.gov (United States)

    Noel, Peter B.; Willer, Konstantin; Fingerle, Alexander A.; Gromann, Lukas B.; De Marco, Fabio; Scherer, Kai H.; Herzen, Julia; Achterhold, Klaus; Gleich, Bernhard; Münzel, Daniela; Renz, Martin; Renger, Bernhard C.; Fischer, Florian; Braun, Christian; Auweter, Sigrid; Hellbach, Katharina; Reiser, Maximilian F.; Schröter, Tobias; Mohr, Jürgen; Yaroshenko, Andre; Maack, Hanns-Ingo; Pralow, Thomas; van der Heijden, Hendrik; Proksa, Roland; Köhler, Thomas; Wieberneit, Nataly; Rindt, Karsten; Rummeny, Ernst J.; Pfeiffer, Franz

    2017-03-01

    Purpose: To evaluate the performance of an experimental X-ray dark-field radiography system for chest imaging in humans and to compare with conventional diagnostic imaging. Materials and Methods: The study was institutional review board (IRB) approved. A single human cadaver (52 years, female, height: 173 cm, weight: 84 kg, chest circumference: 97 cm) was imaged within 24 hours post mortem on the experimental x-ray dark-field system. In addition, the cadaver was imaged on a clinical CT system to obtain a reference scan. The grating-based dark-field radiography setup was equipped with a set of three gratings to enable grating-based dark-field contrast x-ray imaging. The prototype operates at an acceleration voltage of up to 70 kVp and with a field-of-view large enough for clinical chest x-ray (>35 x 35 cm2). Results: It was feasible to extract x-ray dark-field signal of the whole human thorax, clearly demonstrating that human x-ray dark-field chest radiography is feasible. Lung tissue produced strong scattering, reflected in a pronounced x-ray dark-field signal. The ribcage and the backbone are less prominent than the lung but are also distinguishable. Finally, the soft tissue is not present in the dark-field radiography. The regions of the lungs affected by edema, as verified by CT, showed less dark-field signal compared to healthy lung tissue. Conclusion: Our results reveal the current status of translating dark-field imaging from a micro (small animal) scale to a macro (patient) scale. The performance of the experimental x-ray dark-field radiography setup offers, for the first time, obtaining multi-contrast chest x-ray images (attenuation and dark-field signal) from a human cadaver.

  19. Chest radiography in acute traumatic rupture of the thoracic aorta

    Energy Technology Data Exchange (ETDEWEB)

    Heystraten, F.M.; Rosenbusch, G.; Kingma, L.M.; Lacquet, L.K.; Boo, T. de; Lemmens, W.A.

    Of 123 patients who had suffered blunt trauma to the chest traumatic aortic rupture was eventually confirmed in 61 and absent in 62 patients. The chest radiographs of these patients were examined for 15 signs reported in the literature as being associated with traumatic aortic rupture. Although many individual signs were significantly more frequent in the aortic rupture group they were not useful in differentiating between patients with and those without rupture of the aorta. By using discriminant analysis combining 2 or 3 signs, patients were classified as having aortic rupture or not. The best discrimination between the two groups was obtained using the combined signs of a widened paratracheal stripe, and opacified pulmonary window, a widened right paraspinal interface and a displaced nasogastric tube.

  20. Association of Aortic Calcification on Plain Chest Radiography with Obstructive Coronary Artery Disease

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Yeong Han; Chang, Jeong Ho [Dept. of Diagnostic Radiology, Daegu Catholic University Hospital, Daegu (Korea, Republic of); Park, Jong Sam [Dept. of Radiologic Tecnology, Daegu Health College, Daegu (Korea, Republic of)

    2009-03-15

    This study was conducted to determine an association between aortic calcification viewed on plain chest radiography and obstructive coronary artery disease. Retrospective review of all chest radiography obtained from consecutive patients undergoing coronary angiography. Chest PA images were reviewed by technical radiologist and radiologist. Considering the presence of aortic arch calcification, images were compared with the results of coronary angiography. In addition, the size of aortic arch calcification were divided into two groups - the smaller and the larger than 10 mm. Among the total 846 patients, the number of the patients with obstructive coronary artery disease is total 417 (88.3%) in males and 312 (83.4%) in females. Considering the presence of aortic arch calcification, the positive predictive value of relation between aortic arch calcification and obstructive coronary artery disease was 91.4% and the relative risk of the group with aortic arch calcification to the opposite group was 1.10. According to the size of aortic arch calcification and obstructive coronary artery disease, the positive predictive value was 91.9% and the relative risk between two groups was 1.04. This study shows that aortic calcification was closely associated with obstructive coronary artery disease. If the aortic calcification is notified on plain chest radiography, we strongly recommend to consult with doctor.

  1. OPTIMIZATION OF RADIATION PROTECTION BY ELIMINATING WEEDS OUT RASTER DIGITAL RADIOGRAPHY OF THE CHEST

    Directory of Open Access Journals (Sweden)

    I. G. Kamyshanskaja

    2015-01-01

    Full Text Available An experimental study of the possibility of eliminating the raster digital radiography. On stationary digital x-ray machine produced 117 x-ray images of the test object and x-rays of the chest cavity with the gridand without him several patients-volunteers. Proven ability to eliminate grid digital radiography by digital processing of images, made without the grid that reduces dose radiation exposure of the patient more than in 3 times. «Virtual» grids enough improve the diagnostic quality of the photo to eliminate the pathology.

  2. Image lag modeling and correction method for flat panel detector in cone-beam CT%锥束CT平板探测器成像的余晖建模与校正方法

    Institute of Scientific and Technical Information of China (English)

    黄魁东; 张定华; 李明君; 张华

    2013-01-01

    Cone-beam computed tomography (CT) has the notable features, viz high efficiency and high precision, and is widely used in the areas such as medical imaging and industrial non-destructive testing, but the presence of image lag reduces the quality of CT images. By referencing the multi-exponential decay model for the image lag and combining with the actual decay rule of the flat panel detector output signal, a new decay modeling and correction method for the image lag based on multi-exponential fitting is proposed. Firstly, an imaging experiment using cone-beam CT based on flat panel detector is carried out;the results show that the image lag decay of the pixels in the flat panel detector has a good consistency, and is irrelevant to the initial gray value. Then, the rapid image lag correction is achieved according to the image lag decay model, and the comparison of image quality of the projected images and slice images before and after image lag correction indicates that the edge sharpness of the part has been significantly improved after the lag correction. This method does not need to obtain the scintillation compositions and the decay time constants of the detector, and is easily applied to the practical cone-beam CT imaging systems for image lag detection and correction.%锥束CT具有高效率和高精度的显著特点,在医学成像与工业无损检测等领域已得到广泛应用,但余晖的存在降低了CT图像的质量。本文借鉴余晖多指数衰减模型的思想,结合平板探测器输出信号的实际衰减规律,提出了一种新的基于多指数拟合的余晖衰减建模及校正方法。首先进行了基于平板探测器的锥束CT成像实验,结果表明平板探测器各像素的余晖衰减规律具有良好的一致性,且余晖衰减规律与初始灰度的大小无关;其后根据建立的余晖衰减模型实现了余晖的快速校正,并分析比较了余晖校正前后投影图像和切片图像质量,

  3. Indirect flat-panel detector with avalanche gain: fundamental feasibility investigation for SHARP-AMFPI (scintillator HARP active matrix flat panel imager).

    Science.gov (United States)

    Zhao, Wei; Li, Dan; Reznik, Alla; Lui, B J M; Hunt, D C; Rowlands, J A; Ohkawa, Yuji; Tanioka, Kenkichi

    2005-09-01

    An indirect flat-panel imager (FPI) with avalanche gain is being investigated for low-dose x-ray imaging. It is made by optically coupling a structured x-ray scintillator CsI(Tl) to an amorphous selenium (a-Se) avalanche photoconductor called HARP (high-gain avalanche rushing photoconductor). The final electronic image is read out using an active matrix array of thin film transistors (TFT). We call the proposed detector SHARP-AMFPI (scintillator HARP active matrix flat panel imager). The advantage of the SHARP-AMFPI is its programmable gain, which can be turned on during low dose fluoroscopy to overcome electronic noise, and turned off during high dose radiography to avoid pixel saturation. The purpose of this paper is to investigate the important design considerations for SHARP-AMFPI such as avalanche gain, which depends on both the thickness d(Se) and the applied electric field E(Se) of the HARP layer. To determine the optimal design parameter and operational conditions for HARP, we measured the E(Se) dependence of both avalanche gain and optical quantum efficiency of an 8 microm HARP layer. The results were used in a physical model of HARP as well as a linear cascaded model of the FPI to determine the following x-ray imaging properties in both the avalanche and nonavalanche modes as a function of E(Se): (1) total gain (which is the product of avalanche gain and optical quantum efficiency); (2) linearity; (3) dynamic range; (4) gain nonuniformity resulting from thickness nonuniformity; and (5) effects of direct x-ray interaction in HARP. Our results showed that a HARP layer thickness of 8 microm can provide adequate avalanche gain and sufficient dynamic range for x-ray imaging applications to permit quantum limited operation over the range of exposures needed for radiography and fluoroscopy.

  4. An investigation of automatic exposure control calibration for chest imaging with a computed radiography system.

    Science.gov (United States)

    Moore, C S; Wood, T J; Avery, G; Balcam, S; Needler, L; Beavis, A W; Saunderson, J R

    2014-05-07

    The purpose of this study was to examine the use of three physical image quality metrics in the calibration of an automatic exposure control (AEC) device for chest radiography with a computed radiography (CR) imaging system. The metrics assessed were signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and mean effective noise equivalent quanta (eNEQm), all measured using a uniform chest phantom. Subsequent calibration curves were derived to ensure each metric was held constant across the tube voltage range. Each curve was assessed for its clinical appropriateness by generating computer simulated chest images with correct detector air kermas for each tube voltage, and grading these against reference images which were reconstructed at detector air kermas correct for the constant detector dose indicator (DDI) curve currently programmed into the AEC device. All simulated chest images contained clinically realistic projected anatomy and anatomical noise and were scored by experienced image evaluators. Constant DDI and CNR curves do not appear to provide optimized performance across the diagnostic energy range. Conversely, constant eNEQm and SNR do appear to provide optimized performance, with the latter being the preferred calibration metric given as it is easier to measure in practice. Medical physicists may use the SNR image quality metric described here when setting up and optimizing AEC devices for chest radiography CR systems with a degree of confidence that resulting clinical image quality will be adequate for the required clinical task. However, this must be done with close cooperation of expert image evaluators, to ensure appropriate levels of detector air kerma.

  5. The Dexela 2923 CMOS X-ray detector: A flat panel detector based on CMOS active pixel sensors for medical imaging applications

    Science.gov (United States)

    Konstantinidis, Anastasios C.; Szafraniec, Magdalena B.; Speller, Robert D.; Olivo, Alessandro

    2012-10-01

    Complementary metal-oxide-semiconductors (CMOS) active pixel sensors (APS) have been introduced recently in many scientific applications. This work reports on the performance (in terms of signal and noise transfer) of an X-ray detector that uses a novel CMOS APS which was developed for medical X-ray imaging applications. For a full evaluation of the detector's performance, electro-optical and X-ray characterizations were carried out. The former included measuring read noise, full well capacity and dynamic range. The latter, which included measuring X-ray sensitivity, presampling modulation transfer function (pMTF), noise power spectrum (NPS) and the resulting detective quantum efficiency (DQE), was assessed under three beam qualities (28 kV, 50 kV (RQA3) and 70 kV (RQA5) using W/Al) all in accordance with the IEC standard. The detector features an in-pixel option for switching the full well capacity between two distinct modes, high full well (HFW) and low full well (LFW). Two structured CsI:Tl scintillators of different thickness (a “thin” one for high resolution and a thicker one for high light efficiency) were optically coupled to the sensor array to optimize the performance of the system for different medical applications. The electro-optical performance evaluation of the sensor results in relatively high read noise (∼360 e-), high full well capacity (∼1.5×106 e-) and wide dynamic range (∼73 dB) under HFW mode operation. When the LFW mode is used, the read noise is lower (∼165) at the expense of a reduced full well capacity (∼0.5×106 e-) and dynamic range (∼69 dB). The maximum DQE values at low frequencies (i.e. 0.5 lp/mm) are high for both HFW (0.69 for 28 kV, 0.71 for 50 kV and 0.75 for 70 kV) and LFW (0.69 for 28 kV and 0.7 for 50 kV) modes. The X-ray performance of the studied detector compares well to that of other mammography and general radiography systems, obtained under similar experimental conditions. This demonstrates the suitability

  6. An indirect flat-panel detector with avalanche gain for low dose x-ray imaging: SAPHIRE (scintillator avalanche photoconductor with high resolution emitter readout)

    Science.gov (United States)

    Zhao, Wei; Li, Dan; Rowlands, J. A.; Egami, N.; Takiguchi, Y.; Nanba, M.; Honda, Y.; Ohkawa, Y.; Kubota, M.; Tanioka, K.; Suzuki, K.; Kawai, T.

    2008-03-01

    An indirect flat-imager with programmable avalanche gain and field emitter array (FEA) readout is being investigated for low-dose x-ray imaging with high resolution. It is made by optically coupling a structured x-ray scintillator CsI (Tl) to an amorphous selenium (a-Se) avalanche photoconductor called HARP (high-gain avalanche rushing photoconductor). The charge image created by HARP is read out by electron beams generated by the FEA. The proposed detector is called SAPHIRE (Scintillator Avalanche Photoconductor with HIgh Resolution Emitter readout). The avalanche gain of HARP depends on both a-Se thickness and applied electric field E Se. At E Se of > 80 V/μm, the avalanche gain can enhance the signal at low dose (e.g. fluoroscopy) and make the detector x-ray quantum noise limited down to a single x-ray photon. At high exposure (e.g. radiography), the avalanche gain can be turned off by decreasing E Se to < 70 V/μm. In this paper the imaging characteristics of the FEA readout method, including the spatial resolution and noise, were investigated experimentally using a prototype optical HARP-FEA image sensor. The potential x-ray imaging performance of SAPHIRE, especially the aspect of programmable gain to ensure wide dynamic range and x-ray quantum noise limited performance at the lowest exposure in fluoroscopy, was investigated.

  7. Diagnostic Accuracy of Ultrasonography and Radiography in Initial Evaluation of Chest Trauma Patients

    Directory of Open Access Journals (Sweden)

    Ali Vafaei

    2016-01-01

    Full Text Available Introduction: Application of chest radiography for all multiple trauma patients is associated with a significant increase in total costs, exposure to radiation, and overcrowding of the emergency department. Ultrasound has been introduced as an alternative diagnostic tool in this regard. The aim of the present study is to compare the diagnostic accuracy of chest ultrasonography and radiography in detection of traumatic intrathoracic injuries. Methods: In the present prospective cross-sectional study, patients with traumatic intrathoracic injuries, who were referred to the emergency department from December 2013 to December 2014, were assessed. The patients underwent bedside ultrasound, radiographic and computed tomography (CT scan examinations based on ATLS recommendations. Screening performance characteristics of ultrasonography and radiography were compared using SPSS 21.0. Chest CT scan was considered as gold standard. Results: 152 chest trauma patients with a mean age of 31.4 ± 13.8 years (range: 4 ‒ 67, were enrolled (77.6% male. Chest CT scan showed pulmonary contusion in 48 (31.6% patients, hemothorax in 29 (19.1%, and pneumothorax in 55 (36.2% cases. Area under the ROC curve of ultrasonography in detection of pneumothorax, hemothorax, and pulmonary contusion were 0.91 (95% CI: 0.86‒0.96, 0.86 (95% CI: 0.78‒0.94, and 0.80 (95% CI: 0.736‒0.88, respectively. Area under the ROC curve of radiography was 0.80 (95% CI: 0.736‒0.87 for detection of pneumothorax, 0.77 (95% CI: 0.68‒0.86 for hemothorax, and 0.58 (95% CI: 0.5‒0.67 for pulmonary contusion. Comparison of areas under the ROC curve declared the significant superiority of ultrasonography in detection of pneumothorax (p = 0.02 and pulmonary contusion (p < 0.001. However, the diagnostic value of the two tests was equal in detection of hemothorax (p = 0.08. Conclusion: The results of the present study showed that ultrasonography is preferable to radiography in the initial

  8. Routine chest radiography after permanent pacemaker implantation: Is it necessary?

    Directory of Open Access Journals (Sweden)

    Edwards N

    2005-01-01

    Full Text Available Background and Aims: Chest radiographs (CXRs are performed routinely after permanent pacemaker implantation to identify pacemaker lead position and exclude pneumothorax. We assessed the clinical value and need for this procedure. Design: Retrospective analysis of pacemaker data and CXRs following permanent pacemaker insertion between December 2002 and February 2004. Materials and Methods: Post-procedural CXRs were available in 125/126 consecutive patients after either first endocardial pacemaker implantation or insertion of at least one new lead. Subclavian vein puncture was used for venous access in all cases. CXRs were examined to establish the incidence of pneumothorax and assess pacing lead positions. The clinical records were examined in all patients who had subsequent CXRs or a further pacemaker procedure to identify the indication for these and to establish whether CXR had influenced patient management. Results: In total, 192 post-procedural CXRs were performed, either postero-anterior (PA and/or lateral views. Ventricular and/or atrial pacing lead contour and electrode position was considered radiographically appropriate in 86% CXRs. Fourteen per cent of post-procedural radiographs were considered to have radiologically sub-optimal pacemaker lead positioning. None of the patients with these "abnormal" radiographs experienced subsequent pacemaker complications or had further radiographs recorded at a later date. Later repeat CXRs were performed in 16 patients (13% but only 3 patients (2% had pacing abnormalities as the primary indication. All three had satisfactory pacing lead position on initial post-implantation and later radiographs, but required further procedures for lead re-positioning. Iatrogenic pneumothorax occurred in one patient (incidence 0.8% in our series. CXR confirmed the clinical diagnosis and allowed an assessment of size to guide treatment. Conclusion: Routine CXR after permanent pacemaker insertion is not necessary in

  9. Non-destructive, preclinical evaluation of root canal anatomy of human teeth with flat-panel detector volume CT (FD-VCT); Zerstoerungsfreie praeklinische Evaluation der Wurzelkanalanatomie menschlicher Zaehne mittels Flaechendetektor-Volumen-CT (FD-VCT)

    Energy Technology Data Exchange (ETDEWEB)

    Heidrich, G.; Hassepass, F.; Dullin, C.; Grabbe, E. [Universitaetsklinikum Goettingen, Abt. Diagnostische Radiologie (Germany); Attin, T.; Hannig, C. [Universitaetsklinikum Goettingen, Abt. fuer Zahnerhaltung, Praeventive Zahnheilkunde und Paradontologie (Germany)

    2005-12-15

    Purpose: Successful endodontic diagnostics and therapy call for adequate depiction of the root canal anatomy with multimodal diagnostic imaging. The aim of the present study is to evaluate visualization of the endodont with flat-panel detector volume CT (FD-VCT). Materials and methods: 13 human teeth were examined with the prototype of a FD-VCT. After data acquisition and generation of volume data sets in volume rendering technology (VRT), the findings obtained were compared to conventional X-rays and cross-section preparations of the teeth. Results: The anatomical structures of the endodont such as root canals, side canals and communications between different root canals as well as dentricles could be detected precisely with FD-VCT. The length of curved root canals was also determined accurately. The spatial resolution of the system is around 140 {mu}m. Only around 73% of the main root canals detected with FD-VCT and 87% of the roots could be visualized with conventional dental X-rays. None of the side canals, shown with FD-VCT, was detectable on conventional X-rays. In all cases the enamel and dentin of the teeth could be well delineated. No differences in image quality could be discerned between stored and freshly extracted teeth, or between primary and adult teeth. (orig.)

  10. Comparison of dose and image quality of a Flat-panel detector and an image intensifier; Comparacao da dose e qualidade da imagem de um detector Flatpanel e um intensificador de imagem

    Energy Technology Data Exchange (ETDEWEB)

    Lazzaro, M.; Friedrich, B.Q.; Luz, R.M. da; Silva, A.M.M. da, E-mail: marcos.lazzaro@acad.pucrs.br [Pontificia Universidade Catolica do Rio Grande do Sul (PUC-RS), Porto Alegre, RS (Brazil)

    2016-07-01

    With the development of new technologies, have emerged new conversion methods of X-ray image, such as flat panel detectors. The aim of this work is the comparison of entrance surface air kerma (ESAK) and image quality between an image intensifier type of detector (A) and a flat panel (B). The ESAK was obtained by placing a ionization chamber under PMMA simulators of 10, 20 and 30 cm and the image quality was obtained by using the TOR {sup 18}FG simulator. The ESAK to the equipment A is higher when compared to the equipment B. The high contrast resolution is better for the equipment A for all thicknesses of simulators. The equipment A has low contrast resolution with a better viewing threshold for thicknesses of 10 and 20 cm, and a worse performance for 30 cm. It is concluded that the equipment B has ESAK smaller and despite having lower resolution, in almost all cases, have appropriate image quality for diagnosis. (author)

  11. 全数字化乳腺平板摄影技术探讨%Research of Examination Technique of Digital Mammography Using Digital Flat Panel Detector System

    Institute of Scientific and Technical Information of China (English)

    许静; 袁彩云; 徐莉

    2011-01-01

    目的:探讨数字化乳腺摄影规范的操作方法,以优化乳腺图像质量,从而提高乳腺病变的检出率和诊断的正确率.方法:回顾性分析4 000例患者的数字化乳腺摄影的图像,对每一个摄影位置的摆位方法进行主观评价,对相应图像质量进行分级,进行相关性总结分析.结果:15 420幅所摄图像中,规范操作获得的Ⅰ级片15 012幅,占97.35%;因患者配合问题、不规范操作、设备引起的图像质量下降等问题导致的Ⅱ级片达376幅,占2.44%:需重新拍摄有32次,占0.21%.结论:在全数字化乳腺摄影中,高质量乳腺片的获得需规范的摄影投照方法、定期的设备质量图像校正.%Objective To research the normative operation method of digital mammography for optimizing image quality, so as to improve the diagnostic accuracy of pathological changes. Methods Four thousand cases of mammography images were analyzed retrospectively. Each radiography operation method was evaluated in image quality classification. The relationship between mammography operation and image quality was analyzed. Results There were 15,012 images classified as class I, which accounted for 97.35% among all 15,420 images, and 376 images(2.44%) were class II, which were caused by patient's bad cooperation, abnormal operation of technician and other causes of equipment problem. Thirty two images (0.21%) needed re-operation of mammography due to severely low image quality. Conclusion For acquisition of high quality of mammography images, normative mammography operation and periodical equipment image quality calibration are essential.[Chinese Medical Equipment Journal.2011,32( 12): 112-113

  12. Tropical pulmonary eosinophilia: a comparative evaluation of plain chest radiography and computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Sandhu Manavijit; Mukhopadhyay Sima; Sharma, S.K. [All India Inst. of Medical Sciences, New Delhi (India). Dept. of Nuclear Medicine

    1996-02-01

    Plain chest radiography and computed tomography (CT) of the chest were performed on 10 patients with tropical pulmonary eosinophilia (TPE). Chest radiographs revealed bilateral diffuse lesions in the lungs of all the patients with relative sparing of lower lobes in one patient. However, computed tomography revealed bilateral diffuse lung lesions in all of the patients with relative sparing of lower lobes in three patients. In seven (70%) of the 10 patients, CT provided additional information. Computed tomography was found to be superior for the detection of reticulonodular pattern, bronchiectasis, air trapping, calcification and mediastinal adenopathy. No correlation was found between pulmonary function and gas exchange data using CT densities. There was also no correlation between the absolute eosinophil count (AEC) and the radiological severity of lesions. In six patients, high-resolution CT (HRCT) was performed in addition to conventional CT (CCT), and nodularity of lesions was better appreciated in these patients. It is concluded from this study that CT is superior to plain radiography for the evaluation of patients with TPE. 17 refs., 2 tabs., 4 figs.

  13. Comparison of chest radiography, chest digital tomosynthesis and low dose MDCT to detect small ground-glass opacity nodules: an anthropomorphic chest phantom study

    Energy Technology Data Exchange (ETDEWEB)

    Doo, Kyung Won; Kang, Eun-Young; Yong, Hwan Seok [Korea University Guro Hospital, Korea University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Ham, Soo-Youn [Korea University Anam Hospital, Korea University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Lee, Ki Yeol; Choo, Ji Yung [Korea University Ansan Hospital, Korea University College of Medicine, Department of Radiology, Ansan (Korea, Republic of)

    2014-12-15

    The purpose of this study was to evaluate the diagnostic performance of chest radiography (CXR), chest digital tomosynthesis (DT) and low dose multidetector computed tomography (LDCT) for the detection of small pulmonary ground-glass opacity (GGO) nodules, using an anthropomorphic chest phantom. Artificial pulmonary nodules were placed in a phantom and a total of 40 samples of different nodule settings underwent CXR, DT and LDCT. The images were randomly read by three experienced chest radiologists. Free-response receiver-operating characteristics (FROC) were used. The figures of merit for the FROC curves averaged for the three observers were 0.41, 0.37 and 0.76 for CXR, DT and LDCT, respectively. FROC analyses revealed significantly better performance of LDCT over CXR or DT for the detection of GGO nodules (P < 0.05). The difference in detectability between CXR and DT was not statistically significant (P = 0.73). The diagnostic performance of DT for the detection of pulmonary small GGO nodules was not significantly different from that of CXR, but LDCT performed significantly better than both CXR and DT. DT is not a suitable alternative to CT for small GGO nodule detection, and LDCT remains the method of choice for this purpose. (orig.)

  14. Detection of rib fractures in minor chest injuries: a comparison between ultrasonography and radiography performed on the same day

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Yong Soo; Back, Chang Hee; Lee, Kyung Rae; Shin, Yun Hack; Whang, Yeong Seop; Jeong, Ku Young [Yeosu Baek Hospital, Yeosu (Korea, Republic of); Chung, Soo Hyun [NamWon Medical Center, NamWon (Korea, Republic of); Whang, Cheol Mog [Konyang University Hospital, Daejeon (Korea, Republic of)

    2007-04-15

    We wished to compare the ability of ultrasonography and radiography performed on the same day to detect rib fractures in minor chest injuries. Two hundred and fifteen patients with minor chest injuries were selected. Radiography and ultrasonography were performed on the same day with these patients. Chest wall pain was the only presenting symptom. Two radiologists performed ultrasonography. Fractures were identified by a disruption of the anterior margin of the rib and costal cartilage. The incidence and location of fractures and complications revealed by radiography and ultrasonography were compared. Radiographs revealed the presence of 70 rib fractures in 50 (23%) of 215 patients and ultrasonography revealed the presence of 203 rib fractures in 133 (62%) of 215 patients. Ultrasonography uniquely identified 133 rib fractures in 83 patients. Ultrasonography identified a 2.9 fold increase in the number of fractures in a 2.6 fold number of subjects as compared to radiography. Of the 203 sonographically detected fractures, 201 were located in the rib, one was located at the costochondral junction, and one in the costal cartilage. There were no complications seen by either radiography or ultrasonography. Ultrasonography reveals more fractures than those that may be overlooked on radiography for minor chest injuries.

  15. Comparison between radiation exposure levels using an image intensifier and a flat-panel detector-based system in image-guided central venous catheter placement in children weighing less than 10 kg

    Energy Technology Data Exchange (ETDEWEB)

    Miraglia, Roberto; Maruzzelli, Luigi; Cortis, Kelvin; Gerasia, Roberta; Maggio, Simona; Luca, Angelo [Diagnostic and Therapeutic Services, Mediterranean Institute for Transplantation and Advanced Specialized Therapies (ISMETT), Palermo (Italy); Piazza, Marcello [Department of Anesthesia, Mediterranean Institute for Transplantation and Advanced Specialized Therapies (ISMETT), Palermo (Italy); Tuzzolino, Fabio [Department of Information Technology, Mediterranean Institute for Transplantation and Advanced Specialized Therapies (ISMETT), Palermo (Italy)

    2014-09-10

    Ultrasound-guided central venous puncture and fluoroscopic guidance during central venous catheter (CVC) positioning optimizes technical success and lowers the complication rates in children, and is therefore considered standard practice. The purpose of this study was to compare the radiation exposure levels recorded during CVC placement in children weighing less than 10 kg in procedures performed using an image intensifier-based angiographic system (IIDS) to those performed in a flat-panel detector-based interventional suite (FPDS). A retrospective review of 96 image-guided CVC placements, between January 2008 and October 2013, in 49 children weighing less than 10 kg was performed. Mean age was 8.2 ± 4.4 months (range: 1-22 months). Mean weight was 7.1 ± 2.7 kg (range: 2.5-9.8 kg). The procedures were classified into two categories: non-tunneled and tunneled CVC placement. Thirty-five procedures were performed with the IIDS (21 non-tunneled CVC, 14 tunneled CVC); 61 procedures were performed with the FPDS (47 non-tunneled CVC, 14 tunneled CVC). For non-tunneled CVC, mean DAP was 113.5 ± 126.7 cGy cm{sup 2} with the IIDS and 15.9 ± 44.6 cGy . cm{sup 2} with the FPDS (P < 0.001). For tunneled CVC, mean DAP was 84.6 ± 81.2 cGy . cm{sup 2} with the IIDS and 37.1 ± 33.5 cGy cm{sup 2} with the FPDS (P = 0.02). The use of flat-panel angiographic equipment reduces radiation exposure in small children undergoing image-guided CVC placement. (orig.)

  16. Detection of lung nodules. New opportunities in chest radiography; Detektion pulmonaler Rundherde. Neue Moeglichkeiten der Thoraxradiographie

    Energy Technology Data Exchange (ETDEWEB)

    Poetter-Lang, S. [Medizinische Universitaet Wien, Universitaetsklinik fuer Radiologie und Nuklearmedizin, Department of Biomedical Imaging and Image-Guided Therapy, Wien (Austria); Schalekamp, S. [Radboud University Nijmegen Medical Center, Nijmegen (Netherlands); Schaefer-Prokop, C. [Radboud University Nijmegen Medical Center, Nijmegen (Netherlands); Meander Medical Center Amersfoort, Amersfoort (Netherlands); Uffmann, M. [Landesklinikum Neunkirchen, Abteilung fuer Radiodiagnostik, Neunkirchen (Germany)

    2014-05-15

    Chest radiography still represents the most commonly performed X-ray examination because it is readily available, requires low radiation doses and is relatively inexpensive. However, as previously published, many initially undetected lung nodules are retrospectively visible in chest radiographs. The great improvements in detector technology with the increasing dose efficiency and improved contrast resolution provide a better image quality and reduced dose needs. The dual energy acquisition technique and advanced image processing methods (e.g. digital bone subtraction and temporal subtraction) reduce the anatomical background noise by reduction of overlapping structures in chest radiography. Computer-aided detection (CAD) schemes increase the awareness of radiologists for suspicious areas. The advanced image processing methods show clear improvements for the detection of pulmonary lung nodules in chest radiography and strengthen the role of this method in comparison to 3D acquisition techniques, such as computed tomography (CT). Many of these methods will probably be integrated into standard clinical treatment in the near future. Digital software solutions offer advantages as they can be easily incorporated into radiology departments and are often more affordable as compared to hardware solutions. (orig.) [German] Das Thoraxroentgen mit den Vorteilen der schnellen Verfuegbarkeit, geringen Strahlendosis und geringen Kosten ist unveraendert die haeufigste radiologische Untersuchung. Es wurde jedoch vielfach publiziert, dass primaer im Thoraxroentgen uebersehene Lungenrundherde retrospektiv sichtbar waren. Die grossen Fortschritte der Detektortechnologie mit verbesserter Dosiseffizienz und Ortsaufloesung der Systeme fuehren zu einer gesteigerten Bildqualitaet bei geringerem Dosisbedarf. Die Dual-energy-Aufnahmetechnik sowie auch Bildverarbeitungsmethoden wie die digitale Knochensubtraktion und die ''temporal subtraction'' reduzieren das &apos

  17. Bone images from dual-energy subtraction chest radiography in the detection of rib fractures

    Energy Technology Data Exchange (ETDEWEB)

    Szucs-Farkas, Zsolt, E-mail: zsolt.szuecs@insel.ch [Department of Diagnostic, Interventional and Pediatric Radiology, University Hospital Bern, Freiburgstrasse 4, Bern CH-3010 (Switzerland); Lautenschlager, Katrin, E-mail: katrin@students.unibe.ch [Department of Diagnostic, Interventional and Pediatric Radiology, University Hospital Bern, Freiburgstrasse 4, Bern CH-3010 (Switzerland); Flach, Patricia M., E-mail: patricia.flach@irm.unibe.ch [Institute of Forensic Medicine, University of Bern, Freiburgstrasse 4, Bern CH-3010 (Switzerland); Ott, Daniel, E-mail: daniel.ott@insel.ch [Department of Diagnostic, Interventional and Pediatric Radiology, University Hospital Bern, Freiburgstrasse 4, Bern CH-3010 (Switzerland); Strautz, Tamara, E-mail: tamara.strautz@insel.ch [Department of Diagnostic, Interventional and Pediatric Radiology, University Hospital Bern, Freiburgstrasse 4, Bern CH-3010 (Switzerland); Vock, Peter, E-mail: peter.vock@insel.ch [Department of Diagnostic, Interventional and Pediatric Radiology, University Hospital Bern, Freiburgstrasse 4, Bern CH-3010 (Switzerland); Ruder, Thomas D., E-mail: thomas.ruder@irm.unibe.ch [Institute of Forensic Medicine, University of Bern, Freiburgstrasse 4, Bern CH-3010 (Switzerland)

    2011-08-15

    Objective: To assess the sensitivity and image quality of chest radiography (CXR) with or without dual-energy subtracted (ES) bone images in the detection of rib fractures. Materials and methods: In this retrospective study, 39 patients with 204 rib fractures and 24 subjects with no fractures were examined with a single exposure dual-energy subtraction digital radiography system. Three blinded readers first evaluated the non-subtracted posteroanterior and lateral chest radiographs alone, and 3 months later they evaluated the non-subtracted images together with the subtracted posteroanterior bone images. The locations of rib fractures were registered with confidence levels on a 3-grade scale. Image quality was rated on a 5-point scale. Marks by readers were compared with fracture localizations in CT as a standard of reference. Results: The sensivity for fracture detection using both methods was very similar (34.3% with standard CXR and 33.5% with ES-CXR, p = 0.92). At the patient level, both sensitivity (71.8%) and specificity (92.9%) with or without ES were identical. Diagnostic confidence was not significantly different (2.61 with CXR and 2.75 with ES-CXR, p = 0.063). Image quality with ES was rated higher than that on standard CXR (4.08 vs. 3.74, p < 0.001). Conclusions: Despite a better image quality, adding ES bone images to standard radiographs of the chest does not provide better sensitivity or improved diagnostic confidence in the detection of rib fractures.

  18. Image quality for five modern chest radiography techniques: a modified FROC study with an anthropomorphic chest phantom.

    Science.gov (United States)

    Månsson, L G; Kheddache, S; Lanhede, B; Tylén, U

    1999-01-01

    The purpose of the study was to compare the image quality for one conventional and four digital chest radiography techniques. Three storage phosphor systems, one selenium drum system, and one film-screen system were compared using a modified receiver-operating-characteristics method. Simulated pathology was randomly positioned over the parenchymal regions and the mediastinum of an anthropomorphic phantom. Eight observers (four chest radiologists, one specialist in general radiology, one hospital physicist, and two radiographers) evaluated 60 images for each technique. The selenium drum system (Philips, Eindhoven, The Netherlands) rated best for the detection of parenchymal nodules. Together with the storage phosphor system of generation IIIN (Philips/Fuji), the selenium drum system also rated best for detection of thin linear structures. The storage phosphor system of generation V (Fuji) rated best for the detection of mediastinal nodules. The first generation of the storage phosphor system from Agfa (Mortsel, Belgium) rated worst for the detection of parenchymal nodules and thin linear structures. These differences were significant (p drum system and the storage phosphor system of generation V were significantly better than the other systems tested. The film/screen system performed significantly better than the first-generation storage phosphor system from Agfa, equal to the generation IIIN storage phosphor system (Philips/Fuji) and significantly worse than the selenium drum system (Philips) and the generation-V storage phosphor system (Fuji). The conclusion is therefore that the image quality of selenium-based digital technique and of the more recent generations of storage phosphor systems is superior to both conventional technique and storage phosphor systems using image plates of older types.

  19. SU-E-I-53: Comparison of Kerma-Area-Product Between the Micro-Angiographic Fluoroscope (MAF) and a Flat Panel Detector (FPD) as Used in Neuro-Endovascular Procedures

    Energy Technology Data Exchange (ETDEWEB)

    Vijayan, S; Rana, V; Nagesh, S Setlur; Xiong, Z; Rudin, S; Bednarek, D [Toshiba Stroke and Vascular Research Center, University at Buffalo, Buffalo, NY (United States)

    2015-06-15

    Purpose: To determine the reduction of integral dose to the patient when using the micro-angiographic fluoroscope (MAF) compared to when using the standard flat-panel detector (FPD) for the techniques used during neurointerventional procedures. Methods: The MAF is a small field-of-view, high resolution x-ray detector which captures 1024 x 1024 pixels with an effective pixel size of 35μm and is capable of real-time imaging up to 30 frames per second. The MAF was used in neuro-interventions during those parts of the procedure when high resolution was needed and the FPD was used otherwise. The technique parameters were recorded when each detector was used and the kerma-area-product (KAP) per image frame was determined. KAP values were calculated for seven neuro interventions using premeasured calibration files of output as a function of kVp and beam filtration and included the attenuation of the patient table for the frontal projections to be more representative of integral patient dose. The air kerma at the patient entrance was multiplied by the beam area at that point to obtain the KAP values. The ranges of KAP values per frame were determined for the range of technique parameters used during the clinical procedures. To appreciate the benefit of the higher MAF resolution in the region of interventional activity, DA technique parameters were generally used with the MAF. Results: The lowest and highest values of KAP per frame for the MAF in DA mode were 4 and 50 times lower, respectively, compared to those of the FPD in pulsed fluoroscopy mode. Conclusion: The MAF was used in those parts of the clinical procedures when high resolution and image quality was essential. The integral patient dose as represented by the KAP value was substantially lower when using the MAF than when using the FPD due to the much smaller volume of tissue irradiated. This research was supported in part by Toshiba Medical Systems Corporation and NIH Grant R01EB002873.

  20. SU-D-204-05: Quantitative Comparison of a High Resolution Micro-Angiographic Fluoroscopic (MAF) Detector with a Standard Flat Panel Detector (FPD) Using the New Metric of Generalized Measured Relative Object Detectability (GM-ROD)

    Energy Technology Data Exchange (ETDEWEB)

    Russ, M; Ionita, C; Bednarek, D; Rudin, S [Toshiba Stroke and Vascular Research Center, University at Buffalo (SUNY), Buffalo, NY (United States)

    2015-06-15

    Purpose: In endovascular image-guided neuro-interventions, visualization of fine detail is paramount. For example, the ability of the interventionist to visualize the stent struts depends heavily on the x-ray imaging detector performance. Methods: A study to examine the relative performance of the high resolution MAF-CMOS (pixel size 75µm, Nyquist frequency 6.6 cycles/mm) and a standard Flat Panel Detector (pixel size 194µm, Nyquist frequency 2.5 cycles/mm) detectors in imaging a neuro stent was done using the Generalized Measured Relative Object Detectability (GM-ROD) metric. Low quantum noise images of a deployed stent were obtained by averaging 95 frames obtained by both detectors without changing other exposure or geometric parameters. The square of the Fourier transform of each image is taken and divided by the generalized normalized noise power spectrum to give an effective measured task-specific signal-to-noise ratio. This expression is then integrated from 0 to each of the detector’s Nyquist frequencies, and the GM-ROD value is determined by taking a ratio of the integrals for the MAF-CMOS to that of the FPD. The lower bound of integration can be varied to emphasize high frequencies in the detector comparisons. Results: The MAF-CMOS detector exhibits vastly superior performance over the FPD when integrating over all frequencies, yielding a GM-ROD value of 63.1. The lower bound of integration was stepped up in increments of 0.5 cycles/mm for higher frequency comparisons. As the lower bound increased, the GM-ROD value was augmented, reflecting the superior performance of the MAF-CMOS in the high frequency regime. Conclusion: GM-ROD is a versatile metric that can provide quantitative detector and task dependent comparisons that can be used as a basis for detector selection. Supported by NIH Grant: 2R01EB002873 and an equipment grant from Toshiba Medical Systems Corporation.

  1. TU-CD-BRA-11: Application of Bone Suppression Technique to Inspiratory/expiratory Chest Radiography

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, R; Sanada, S [Kanazawa University, Kanazawa, Ishikawa (Japan); Sakuta, K; Kawashima, H [Kanazawa University Hospital, Kanazawa, Ishikawa (Japan); Kishitani, Y [TOYO Corporation, Chuoh-ku, Tokyo (Japan)

    2015-06-15

    Purpose: The bone suppression technique based on advanced image processing can suppress the conspicuity of bones on chest radiographs, creating soft tissue images normally obtained by the dual-energy subtraction technique. This study was performed to investigate the usefulness of bone suppression technique in quantitative analysis of pulmonary function in inspiratory/expiratory chest radiography. Methods: Commercial bone suppression image processing software (ClearRead; Riverain Technologies) was applied to paired inspiratory/expiratory chest radiographs of 107 patients (normal, 33; abnormal, 74) to create corresponding bone suppression images. The abnormal subjects had been diagnosed with pulmonary diseases, such as pneumothorax, pneumonia, emphysema, asthma, and lung cancer. After recognition of the lung area, the vectors of respiratory displacement were measured in all local lung areas using a cross-correlation technique. The measured displacement in each area was visualized as displacement color maps. The distribution pattern of respiratory displacement was assessed by comparison with the findings of lung scintigraphy. Results: Respiratory displacement of pulmonary markings (soft tissues) was able to be quantified separately from the rib movements on bone suppression images. The resulting displacement map showed a left-right symmetric distribution increasing from the lung apex to the bottom region of the lung in many cases. However, patients with ventilatory impairments showed a nonuniform distribution caused by decreased displacement of pulmonary markings, which were confirmed to correspond to area with ventilatory impairments found on the lung scintigrams. Conclusion: The bone suppression technique was useful for quantitative analysis of respiratory displacement of pulmonary markings without any interruption of the rib shadows. Abnormal areas could be detected as decreased displacement of pulmonary markings. Inspiratory/expiratory chest radiography combined

  2. Comparison of patient specific dose metrics between chest radiography, tomosynthesis, and CT for adult patients of wide ranging body habitus

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yakun [Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 (United States); Li, Xiang [Medical Physics Graduate Program, Department of Physics, Cleveland State University, Cleveland, Ohio 44115 (United States); Segars, W. Paul [Medical Physics Graduate Program, Carl E. Ravin Advanced Imaging Laboratories, and Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 (United States); Samei, Ehsan, E-mail: samei@duke.edu [Medical Physics Graduate Program, Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Departments of Physics, Biomedical Engineering, and Electrical and Computer Engineering, Duke University Medical Center, Durham, North Carolina 27705 (United States)

    2014-02-15

    Purpose: Given the radiation concerns inherent to the x-ray modalities, accurately estimating the radiation doses that patients receive during different imaging modalities is crucial. This study estimated organ doses, effective doses, and risk indices for the three clinical chest x-ray imaging techniques (chest radiography, tomosynthesis, and CT) using 59 anatomically variable voxelized phantoms and Monte Carlo simulation methods. Methods: A total of 59 computational anthropomorphic male and female extended cardiac-torso (XCAT) adult phantoms were used in this study. Organ doses and effective doses were estimated for a clinical radiography system with the capability of conducting chest radiography and tomosynthesis (Definium 8000, VolumeRAD, GE Healthcare) and a clinical CT system (LightSpeed VCT, GE Healthcare). A Monte Carlo dose simulation program (PENELOPE, version 2006, Universitat de Barcelona, Spain) was used to mimic these two clinical systems. The Duke University (Durham, NC) technique charts were used to determine the clinical techniques for the radiographic modalities. An exponential relationship between CTDI{sub vol} and patient diameter was used to determine the absolute dose values for CT. The simulations of the two clinical systems compute organ and tissue doses, which were then used to calculate effective dose and risk index. The calculation of the two dose metrics used the tissue weighting factors from ICRP Publication 103 and BEIR VII report. Results: The average effective dose of the chest posteroanterior examination was found to be 0.04 mSv, which was 1.3% that of the chest CT examination. The average effective dose of the chest tomosynthesis examination was found to be about ten times that of the chest posteroanterior examination and about 12% that of the chest CT examination. With increasing patient average chest diameter, both the effective dose and risk index for CT increased considerably in an exponential fashion, while these two dose

  3. Localized Energy-Based Normalization of Medical Images: Application to Chest Radiography.

    Science.gov (United States)

    Philipsen, R H H M; Maduskar, P; Hogeweg, L; Melendez, J; Sánchez, C I; van Ginneken, B

    2015-09-01

    Automated quantitative analysis systems for medical images often lack the capability to successfully process images from multiple sources. Normalization of such images prior to further analysis is a possible solution to this limitation. This work presents a general method to normalize medical images and thoroughly investigates its effectiveness for chest radiography (CXR). The method starts with an energy decomposition of the image in different bands. Next, each band's localized energy is scaled to a reference value and the image is reconstructed. We investigate iterative and local application of this technique. The normalization is applied iteratively to the lung fields on six datasets from different sources, each comprising 50 normal CXRs and 50 abnormal CXRs. The method is evaluated in three supervised computer-aided detection tasks related to CXR analysis and compared to two reference normalization methods. In the first task, automatic lung segmentation, the average Jaccard overlap significantly increased from 0.72±0.30 and 0.87±0.11 for both reference methods to with normalization. The second experiment was aimed at segmentation of the clavicles. The reference methods had an average Jaccard index of 0.57±0.26 and 0.53±0.26; with normalization this significantly increased to . The third experiment was detection of tuberculosis related abnormalities in the lung fields. The average area under the Receiver Operating Curve increased significantly from 0.72±0.14 and 0.79±0.06 using the reference methods to with normalization. We conclude that the normalization can be successfully applied in chest radiography and makes supervised systems more generally applicable to data from different sources.

  4. Initial quality performance results using a phantom to simulate chest computed radiography

    Directory of Open Access Journals (Sweden)

    Muhogora Wilbroad

    2011-01-01

    Full Text Available The aim of this study was to develop a homemade phantom for quantitative quality control in chest computed radiography (CR. The phantom was constructed from copper, aluminium, and polymenthylmethacrylate (PMMA plates as well as Styrofoam materials. Depending on combinations, the literature suggests that these materials can simulate the attenuation and scattering characteristics of lung, heart, and mediastinum. The lung, heart, and mediastinum regions were simulated by 10 mm x 10 mm x 0.5 mm, 10 mm x 10 mm x 0.5 mm and 10 mm x 10 mm x 1 mm copper plates, respectively. A test object of 100 mm x 100 mm and 0.2 mm thick copper was positioned to each region for CNR measurements. The phantom was exposed to x-rays generated by different tube potentials that covered settings in clinical use: 110-120 kVp (HVL=4.26-4.66 mm Al at a source image distance (SID of 180 cm. An approach similar to the recommended method in digital mammography was applied to determine the CNR values of phantom images produced by a Kodak CR 850A system with post-processing turned off. Subjective contrast-detail studies were also carried out by using images of Leeds TOR CDR test object acquired under similar exposure conditions as during CNR measurements. For clinical kVp conditions relevant to chest radiography, the CNR was highest over 90-100 kVp range. The CNR data correlated with the results of contrast detail observations. The values of clinical tube potentials at which CNR is the highest are regarded to be optimal kVp settings. The simplicity in phantom construction can offer easy implementation of related quality control program.

  5. Coronary calcium visualization using dual energy chest radiography with sliding organ registration

    Science.gov (United States)

    Wen, Di; Nye, Katelyn; Zhou, Bo; Gilkeson, Robert C.; Wilson, David L.

    2016-03-01

    Coronary artery calcification (CAC) is the lead biomarker for atherosclerotic heart disease. We are developing a new technique to image CAC using ubiquitously ordered, low cost, low radiation dual energy (DE) chest radiography (using the two-shot GE Revolution XRd system). In this paper, we proposed a novel image processing method (CorCalDx) based on sliding organ registration to create a bone-image-like, coronary calcium image (CCI) that significantly reduces motion artifacts and improves CAC conspicuity. Experiments on images of a physical dynamic cardiac phantom showed that CorCalDx reduced 73% of the motion artifact area as compared to standard DE over a range of heart rates up to 90 bpm and varying x-ray radiation exposures. Residual motion artifact in the phantom CCI is greatly suppressed in gray level and area (0.88% of the heart area). In a Functional Measurement Test (FMT) with 20 clinical exams, image quality improvement of CorCalDx against standard DE (measured from -10 to +10) was significantly suggested (p<0.0001) by three radiologists for cardiac motion artifacts (7.2+/-2.1) and cardiac anatomy visibility (6.1+/-3.5). CorCalDx was always chosen best in every image tested. In preliminary assessments of 12 patients with 18 calcifications, 90% of motion artifact regions in standard DE results were removed in CorCalDx results, with 100% sensitivity of calcification detection, showing great potential of CorCalDx to improve CAC detection and grading in DE chest radiography.

  6. 无线平板探测器在四肢小关节X线摄影中的临床应用%Clinical Application of Wireless Flat-panel Detector in X-ray Photography in the Small Joints of the Limbs

    Institute of Scientific and Technical Information of China (English)

    吴慧钊; 张泽坤; 吴文娟

    2013-01-01

    Purpose To compare the wireless flat-panel detector with gadolinium oxide coating in X-ray photography in the small joints of the limbs compared with conventional flat panel detector with cesium iodide coating. Materials and Methods Comparison was randomly performed between gadolinium oxide coated sulfur wireless flat-panel detector and cesium iodide coated conventional flat-panel detector for 80 patients who received routine X-ray photography, and scoring data were applied with statistical analysis. Results There was no significant difference between the scoring data from two film-reading people (P>0.05). The resolution of anatomical structure of small joint of limbs and tube current showed no significant difference for two types of imaging systems (P>0.05). Conclusion Wireless flat panel detector sulfur with gadolinium oxide coatings can obtain satisfactory image quality at a reasonable inspection doses in the X-ray photography of small joint of limbs. The imaging quality and inspection doses are similar to conventional flat panel detector device with cesium iodide coating, but the posture is more convenient.%目的对硫氧化钆涂层的无线平板探测器与碘化铯涂层的常规平板探测器进行对比,探讨硫氧化钆涂层的无线平板探测器在四肢小关节X线摄影中的应用价值。资料与方法80例行四肢小关节X线摄影患者随机分别使用硫氧化钆涂层的无线平板探测器和碘化铯涂层的常规平板探测器进行检查,对评分数据进行统计学分析。结果2名阅片人评分比较差异无统计学意义(P>0.05)。两种成像系统的四肢小关节解剖结构的显示清晰度差异无统计学意义(P>0.05)。两种成像系统管电流值的差异无统计学意义(P>0.05)。结论在合理的检查剂量下,硫氧化钆涂层的无线平板探测器应用于四肢小关节X线摄影可以获得较满意的图像质量,其成像质量和检查剂量近似于碘化铯涂层

  7. Pneumothorax and the Value of Chest Radiography after Ultrasound-Guided Thoracocentesis

    Energy Technology Data Exchange (ETDEWEB)

    Pihlajamaa, K.; Bode, M.K.; Puumalainen, T.; Lehtimaeki, A.; Marjelund, S.; Tikkakoski, T. [Keski-Pohjanmaan sairaanhoitopiiri, Kokkola (Finland). Rontgenosasto

    2004-12-01

    Purpose: To determine the incidence, the operator's experience, and other variables that may influence the development of pneumothorax or re-expansion edema after ultrasound (US)-guided thoracocentesis. Material and Methods: The medical records of 264 procedures in 212 patients who had undergone US-guided thoracocentesis in our radiology department or intensive care unit during the period 1996-2001 were retrospectively reviewed. Results: Post-thoracocentesis pneumothorax occurred in 11 cases, the incidence being 4.2% (11/264). None of the pneumothoraces occurred in the 10 mechanically ventilated patients. All but one patient with pneumothorax were asymptomatic or had only minor symptoms. Chest tube drainage was needed in one patient with a large pneumothorax. No re-expansion edema was recorded, although 1500 ml or more pleural fluid was aspirated in 29 patients. The operator's experience had no effect on the complication rate. Needle size was the only significant variable that contributed to the pneumothorax rate. Conclusion: US-guided thoracocentesis can be done equally as safely by residents as by senior radiologists. The safety and feasibility of the method are evident among mechanically ventilated intensive care patients. Our results do not support the routine use of post-thoracocentesis chest radiography.

  8. Image quality of a digital chest radiography system based on a selenium detector.

    Science.gov (United States)

    Neitzel, U; Maack, I; Günther-Kohfahl, S

    1994-04-01

    A digital chest radiography system has been developed, with a detector based on the photoelectric properties of amorphous selenium. The selenium layer is deposited on a cylindrical aluminium drum, large enough to cover the full field of view for chest imaging. The electrostatic charge image which is formed on the selenium surface after x-ray exposure is read out by electrometer probes using fast drum rotation. For a physical evaluation of the attainable image quality, the characteristic curve, the modulation transfer function, and the noise spectra were measured. From these measurements, the signal-to-noise properties of the detector in terms of detective quantum efficiency (DQE) and noise equivalent quanta (NEQ) were derived. The results show that the selenium-based detector has a wide dynamic range and a significantly better DQE than screen-film and storage phosphor systems for spatial frequencies below the Nyquist limit (2.7 lp/mm). As a consequence, the detectability of small, low-contrast details is considerably improved.

  9. Large hiatal hernia at chest radiography in a woman with cardiorespiratory symptoms.

    Science.gov (United States)

    Torres, Daniele; Parrinello, Gaspare; Cardillo, Mauro; Pomilla, Marina; Trapanese, Caterina; Michele, Bellanca; Lupo, Umberto; Schimmenti, Caterina; Cuttitta, Francesco; Pietrantoni, Rossella; Vogiatzis, Danai; Licata, Giuseppe

    2012-11-01

    Hiatal hernia (HH) is a frequent entity. Rarely, it may exert a wide spectrum of clinical presentations mimicking acute cardiovascular events such as angina-like chest pain until manifestations of cardiac compression that can include postprandial syncope, exercise intolerance, respiratory function, recurrent acute heart failure, and hemodynamic collapse. A 69-year-old woman presented to the emergency department complaining of fatigue on exertion, cough, and episodes of restrosternal pain with less than 1 hour of duration. Her medical history only included some episodes of bronchitis and no history of hypertension. The 12-lead electrocardiogram demonstrated sinus rhythm with right bundle-branch block. Laboratory tests, including cardiac troponin I, were within normal reference values. Chest radiography showed no significant pulmonary alterations and revealed in mediastinum a huge abnormal shadow overlapping the right heart compatible with a gastric bubble.The gastroscopy confirmed a large HH. A 2-dimensional transthoracic echocardiogram, using all standard and modified apical and parasternal views, revealed an echolucent mass, compatible with HH, compressing the right atrium. Also, it showed an altered left ventricular relaxation and a mild increase of pulmonary artery pressure (35 mm Hg). Spirometry showed a mild obstruction of the small airways, whereas coronary angiography showed normal coronary arteries. We concluded that the patient's symptomatology was related to the compressive effects of the large hiatal ernia, a neglected cause of cardiorespiratory symptoms. The surgical repair of HH was indicated.

  10. Clinical evaluation of irreversible image compression: analysis of chest imaging with computed radiography.

    Science.gov (United States)

    Ishigaki, T; Sakuma, S; Ikeda, M; Itoh, Y; Suzuki, M; Iwai, S

    1990-06-01

    To implement a picture archiving and communication system, clinical evaluation of irreversible image compression with a newly developed modified two-dimensional discrete cosine transform (DCT) and bit-allocation technique was performed for chest images with computed radiography (CR). CR images were observed on a cathode-ray-tube monitor in a 1,024 X 1,536 matrix. One original and five reconstructed versions of the same images with compression ratios of 3:1, 6:1, 13:1, 19:1, and 31:1 were ranked according to quality. Test images with higher spatial frequency were ranked better than those with lower spatial frequency and the acceptable upper limit of the compression ratio was 19:1. In studies of receiver operating characteristics for scoring the presence or absence of nodules and linear shadows, the images with a compression ratio of 25:1 showed a statistical difference as compared with the other images with a compression ratio of 20:1 or less. Both studies show that plain CR chest images with a compression ratio of 10:1 are acceptable and, with use of an improved DCT technique, the upper limit of the compression ratio is 20:1.

  11. Retrodiaphragmatic portion of the lung: how deep is the posterior costophrenic sulcus on posteroanterior chest radiography?

    Energy Technology Data Exchange (ETDEWEB)

    Oh, J.K. [Department of Radiology, Kangnam St Mary' s Hospital, Seoul (Korea, Republic of); Ahn, M.I. [Department of Radiology, Kangnam St Mary' s Hospital, Seoul (Korea, Republic of)], E-mail: ami@catholic.ac.kr; Kim, H.L.; Park, S.H. [Department of Radiology, Kangnam St Mary' s Hospital, Seoul (Korea, Republic of); Shin, E. [Department of Preventive Medicine, The Catholic University of Korea, Seoul (Korea, Republic of)

    2009-08-15

    Aim: To determine the depth of the posterior costophrenic sulcus (CPS) on posteroanterior (PA) chest radiography in relation to the diaphragmatic dome and lateral CPS. Materials and methods: Five hundred and forty consecutive PA chest radiographs that were performed for general health screenings were retrospectively reviewed. Among them 282 radiographs were selected that met the following criteria: visualization of the inferior boundary of the posterior CPS behind the right hemidiaphragm; and no abnormal findings that affected the shape and level of the diaphragm. The selected chest radiographs were from 155 men and 127 women with a mean age of 40.7 {+-} 8.4 years. On 282 PA chest radiographs, the distances between the right diaphragmatic dome and posterior CPS (total diaphragmatic height), the diaphragmatic dome and lateral CPS (diaphragmatic dome height), and the lateral and posterior CPS (posterior CPS depth) were measured. In addition levels of the right lateral and posterior CPS were scored in relation to levels of the thoracic and lumbar spines. The relationships between the posterior CPS depth and demographic and physical data and other radiographic measurements were analysed. Results: The mean right posterior CPS depth was 29.2 {+-} 15.6 mm. The average level of the posterior CPS in relation to the spine was 13.5 {+-} 0.6, i.e., the level of lower half of the L1 vertebral body. The posterior CPS depth had a tendency to be deeper in those participants who were taller (r = 0.17, p < 0.01), had a higher body mass index (BMI; r = 0.25, p < 0.01), longer total diaphragmatic height (r = 0.55, p < 0.01), and shorter diaphragmatic dome height (r = -0.18, p < 0.01). Conclusion: As the posterior CPS is deeper than the lateral CPS by approximately 3 cm, and reaches, on average, to L1, the standard chest PA radiograph must include >3 cm below the level of lateral CPS, or should include the L1 spine.

  12. Effect of External Quality Assurance Evaluation for Chest Radiography: 3-Year Follow-Up in the Medical Institution for Pneumoconiosis

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Won Jeong; Choi, Soon Byung [Clinical Research Team, Occupational Lung Diseases Institute, Korea Worker' s Compensation and Welfare Service, Ansan (Korea, Republic of)

    2012-04-15

    The aim of this study was to determine the effect of external quality assurance (QA) evaluation for chest radiography in the medical institution for pneumoconiosis (MIP). The chest radiography of the MIPs were evaluated for a radiological technique (RT), image quality (IQ), and reading environment (RE), during a 3-year follow up according to the Korean guidelines. Same methods were implemented each year to ensure that the results are reliable. RT, IQ, and RE were compared between examination and medical care (EMP), and only medical care (MCP) for pneumoconiosis, film-screen (FSR) and digital (DR) radiography. Uneducated and educated for QA during a 3-year follow up referencing with 2008 were realized. RT and IQ of the MIPs showed a significantly higher score in 2009 and 2010 compared with 2008 (p < 0.01). However, RE was not significantly improved. The score of RT, IQ, and RE of the EMPs were higher than those of MCPs every year, and FSR showed a lower score in all evaluations, although, more improvement was seen than the DR. The chest radiography of the MIPs showed a significant effect as a result of a repeated external QA evaluation. However, the MIPs need to transfer from FSR to DR, and maintain a continuous QA evaluation for the MCPs.

  13. Chest radiography and thoracic computed tomography findings in children who have family members with active pulmonary tuberculosis

    Energy Technology Data Exchange (ETDEWEB)

    Uzum, Kazim; Karahan, Okkes I.; Dogan, Sukru; Coskun, Abdulhakim E-mail: coskuna@erciyes.edu.tr; Topcu, Faik

    2003-12-01

    Objective: The chest radiography and TCT findings in children who had contacted with adult family members with active pulmonary tuberculosis were compared. The contributions of thoracic computed tomography to the diagnosis of tuberculosis were investigated. Methods and material: The children who were 0-16 years old (n=173) and children of families with an adult member which was diagnosed as pulmonary tuberculosis were evaluated. The children were considered in two groups based on the absence (n=125) or presence (n=48) of complaints and/or ambiguous symptoms such as lack of appetite, mild cough, sweating, history of lung infection, low body weight and those with suspicious chest radiography findings (12 cases) were included in this study. Asymptomatic patients (n=125) did not undergo TCT. Patients who had positive PPD skin tests only received isoniazid. If the TCT demonstrated enlarged lymph nodes or parenchymal lesions, minimally active pulmonary tuberculosis was diagnosed and antituberculous treatment was given. Results and discussions: TCT revealed lymph node enlargement or parenchymal lesions in 39 children (81.2%). Of the 12 children whose CXRs revealed suspicious lymph node enlargement and/or infiltration, five had normal findings in TCT whereas the initial findings were confirmed in the remaining seven. These data suggest that there is a correlation between the presence of ambiguous symptoms in exposed children and TCT findings; chest radiography and TCT findings do not yield parallel findings. All the patients who received anti-TB treatment were resolved in the control examinations. Conclusion: In this study there is a correlation between presence of ambiguous symptoms and TCT findings, but the chest radiography and TCT findings do not yield harmony in exposed children with ambiguous symptoms (suspicious tuberculosis cases). These observations should be considered in children with symptoms similar to those of exposed children, but with no definite history of

  14. Physical imaging properties of a new screen-film system for chest radiography

    Energy Technology Data Exchange (ETDEWEB)

    Higashida, Yoshiharu [Kumamoto Univ. (Japan). Coll. of Medical Science; Yoshida, Akira; Katsuda, Noboru [and others

    1996-04-01

    To evaluate the clinical usefulness of a new screen-film system (advanced screen-film system; AD system) for chest radiography, its fundamental imaging properties were investigated. The basic imaging properties were evaluated by measuring characteristic (H and D) curves, relative speeds, MTFs (modulation transfer functions), WS (Wiener spectra), and x-ray attenuation of screens. The film gradient of the AD system was slightly lower at low radiographic density. and higher at high density. The screen speed of the AD system was 112% greater than that of the conventional system, and the film speed was 47% lower. As the result, the total speed of the AD system was slightly higher compared with the conventional system. Resolution property of the AD system was comparable to or slightly lower than that of the conventional system. However, the noise level of the AD system was considerably lower than that of the conventional system at low and middle photographic density levels. X-ray attenuation of the HG-M screens was about 10% higher than that of the conventional screens. We conclude that the AD system has superior imaging properties than the conventional system. (author).

  15. Evaluation of cancer detection efficiency by means of hybrid and inverse filter in chest radiography

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Youn Young; Kim, Tae Young; Kim, Hyun Ji; Kim, Jung Min [Dept. of Radiological Science, Korea university, Seoul (Korea, Republic of); Park, Min Seock [Radiation Safety and Section, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

    2013-12-15

    The purpose of this study is to evaluate usefulness of Hybrid image and Inverse image about detection of tumor shadow in chest radiography using ROC analysis. Original images of 60 cases are selected from Standards digital image date base issued by the Japanese Society of Radiological Technology. Through computer language of C, Inverse images of 60 cases and Hybrid image of 30 cases are made. The continues reading experiment was conducted. In the case of inverse image were observed by 5 radiographer and 2 radiologist. In the case of In case of Hybrid image were observed by 3 student radiographer and 2 experienced radiographer. ROC curve are constructed using ROCKIT Program made by Metz. In Inverse image, a Az of average ROC curve was increases from 0.742 of original image to 0.775 of inverse image. In normal cases, the effect of the detrimental is same to that of the beneficial, however In abnormal cases, the beneficial effect is greater than detrimental effect. However in Hybrid image, a Az of average ROC curve was decreases from 0.5253 of original image to 0.4868 of Hybrid image. In Normal cases, the effect of the detrimental is greater than that of the Beneficial, however In abnormal cases, the Beneficial effect is greater than detrimental effect. The inverse image can be more positively considered for the detecting of tumor than the hybrid image.

  16. Investigation of optimum energies for chest imaging using film-screen and computed radiography.

    Science.gov (United States)

    Honey, I D; Mackenzie, A; Evans, D S

    2005-05-01

    The purpose of the study was to compare the image quality of film-screen (FS) and computed radiography (CR) for adult chest examinations across a range of beam energies. A series of images of the CDRAD threshold contrast detail detection phantom were acquired for a range of tube potential and exposure levels with both CR and FS. The phantom was placed within 9 cm of Perspex to provide attenuation and realistic levels of scatter in the image. Hardcopy images of the phantom were scored from a masked light-box by two scorers. Threshold contrast indices were used to calculate a visibility index (VI). The relationships between dose and image quality for CR and for FS are fundamentally different. The improvements in VIs obtained using CR at 75 kVp and 90 kVp were found to be statistically significant compared with 125 kVp at matched effective dose levels. The relative performance of FS and CR varies as a function of energy owing to the different k-edges of each system. When changing from FS to CR, the use of lower tube potentials may allow image quality to be maintained whilst reducing effective dose. A tube voltage of 90 kVp is indicated by this work, but may require clinical verification.

  17. Chest radiography versus chest CT in the evaluation for pulmonary metastases in patients with Wilms' tumor: a retrospective review

    Energy Technology Data Exchange (ETDEWEB)

    Wootton-Gorges, S.L.; Albano, E.A.; Riggs, J.M.; Ihrke, H.; Rumack, C.M.; Strain, J.D. [Colorado Univ., Denver, CO (United States). Dept. of Radiology

    2000-08-01

    Background. Determination of the presence of pulmonary metastases in children with Wilms' tumor is an important part of staging and treatment. We sought to compare the efficacy of chest radiography (CXR) and chest CT in the evaluation for pulmonary metastases in patients with Wilms' tumor. Materials and methods. This retrospective study included 83 children with Wilms' tumor diagnosed between 1980 and 1993. All patients with pulmonary nodules (n = 12) as well as 14 Wilms' tumor patients without pulmonary metastases (control group) had blinded review of the CXR and chest CTs by three pediatric radiologists. Presence, size, and certainty of metastatic diagnosis were recorded. Medical records were reviewed. The remaining 57 patients had review of their medical and imaging records to confirm the absence of pulmonary metastases. Results. Ten of the 12 with pulmonary masses had imaging available for review. Eight had both positive CXR and chest CT examinations. Two patients had pulmonary nodules seen by CT only: one had a right cardiophrenic angle mass and died as a result of liver metastases. The other had a solitary nodule, which proved to be a plasma-cell granuloma. Overall, the CXR and chest CT data concur in 79/81 (98 %). Conclusion. CXR alone appears adequate for the diagnosis or exclusion of pulmonary metastases in patients with Wilms' tumor. (orig.)

  18. Screening strategies for tuberculosis prevalence surveys: the value of chest radiography and symptoms.

    Science.gov (United States)

    van't Hoog, Anna H; Meme, Helen K; Laserson, Kayla F; Agaya, Janet A; Muchiri, Benson G; Githui, Willie A; Odeny, Lazarus O; Marston, Barbara J; Borgdorff, Martien W

    2012-01-01

    We conducted a tuberculosis (TB) prevalence survey and evaluated the screening methods used in our survey, to assess if screening in TB prevalence surveys could be simplified, and to assess the accuracy of screening algorithms that may be applicable for active case finding. All participants with a positive screen on either a symptom questionnaire, chest radiography (CXR) and/or sputum smear microscopy submitted sputum for culture. HIV status was obtained from prevalent cases. We estimated the accuracy of modified screening strategies with bacteriologically confirmed TB as the gold standard, and compared these with other survey reports. We also assessed whether sequential rather than parallel application of symptom, CXR and HIV screening would substantially reduce the number of participants requiring CXR and/or sputum culture. Presence of any abnormality on CXR had 94% (95%CI 88-98) sensitivity (92% in HIV-infected and 100% in HIV-uninfected) and 73% (95%CI 68-77) specificity. Symptom screening combinations had significantly lower sensitivity than CXR except for 'any TB symptom' which had 90% (95%CI 84-95) sensitivity (96% in HIV-infected and 82% in HIV-uninfected) and 32% (95%CI 30-34) specificity. Smear microscopy did not yield additional suspects, thus the combined symptom/CXR screen applied in the survey had 100% (95%CI 97-100) sensitivity. Specificity was 65% (95%CI 61-68). Sequential application of first a symptom screen for 'any symptom', followed by CXR-evaluation and different suspect criteria depending on HIV status would result in the largest reduction of the need for CXR and sputum culture, approximately 36%, but would underestimate prevalence by 11%. CXR screening alone had higher accuracy compared to symptom screening alone. Combined CXR and symptom screening had the highest sensitivity and remains important for suspect identification in TB prevalence surveys in settings where bacteriological sputum examination of all participants is not feasible.

  19. What is the yield of routine chest radiography following tube thoracostomy for trauma?

    Science.gov (United States)

    Kong, Victor Y; Oosthuizen, George V; Clarke, Damian L

    2015-01-01

    Routine chest radiography (CXR) following tube thoracostomy (TT) is a standard practice in most trauma centres worldwide. Evidence supporting this routine practice is lacking and the actual yield is unknown. We performed a retrospective review of 1042 patients over a 4-year period who had a routine post-insertion CXR performed in accordance with current ATLS® recommendations. A total 1042 TTs were performed on 1004 patients. Ninety-one per cent of patients (913/1004) were males, and the median age for all patients was 24 years. Seventy-five per cent of all injuries (756/1004) were from penetrating trauma, and the remaining 25% (248/1004) were from blunt. The initial pathologies requiring TT were: haemopneumothorax: 34% (339/1042), haemothroax: 31% (314/1042), simple pneumothorax: 25% (256/1042), tension pneumothorax: 8% (77/1042) and open pneumothorax: 5% (54/1042). One hundred and three patients had TTs performed on clinical grounds alone without a pre-insertion CXR [Group A]. One hundred and ninety-one patients had a pre-insertion CXR but had persistent clinical concerns following insertion [Group B]. Seven hundred and ten patients had pre-insertion CXR but no clinical concerns following insertion [Group C]. Overall, 15% (152/1004) [9 from Group A, 111 from Group B and 32 from Group C] of all patients had their clinical management influenced as a direct result of the post-insertion CXR. Despite the widely accepted practice of routine CXR following tube thoracostomy, the yield is relatively low. In many cases, good clinical examination post tube insertion will provide warnings as to whether problems are likely to result. However, in the more rural setting, and in resource challenged environments, there is a relatively high yield from the CXR, which alters management. Further prospective studies are needed to establish or refute the role of the existing ATLS® guidelines in these specific environments. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Chest radiography patterns in 75 adolescents with vertically-acquired human immunodeficiency virus (HIV) infection

    Energy Technology Data Exchange (ETDEWEB)

    Desai, S.R., E-mail: sujal.desai@nhs.ne [King' s College London, King' s Health Partners, Department of Radiology, King' s College Hospital NHS Foundation Trust (United Kingdom); Copley, S.J. [Department of Radiology, Hammersmith Hospital (United Kingdom); Barker, R.D.; Elston, C.M. [King' s College London, King' s Health Partners, Department of Respiratory Medicine, King' s College Hospital NHS Foundation Trust (United Kingdom); Miller, R.F. [Research Department of Infection and Public Health, Division of Population Health, University College London (United Kingdom); Clinical Research Unit, London School of Hygiene and Tropical Medicine, London (United Kingdom); Wells, A.U. [The Interstitial Lung Disease Unit, Royal Brompton and Harefield NHS Trust, London (United Kingdom); Munyati, S. [Biomedical Research and Training Institute, Samora Machel Avenue (Zimbabwe); Nathoo, K. [Department of Paediatrics, University of Zimbabwe (Zimbabwe); Harare Central Hospital, Lobengula Road, Harare (Zimbabwe); Corbett, E.L.; Ferrand, R.A. [Clinical Research Unit, London School of Hygiene and Tropical Medicine, London (United Kingdom); Biomedical Research and Training Institute, Samora Machel Avenue (Zimbabwe)

    2011-03-15

    Aim: To evaluate lung disease on chest radiography (CR), the relative frequency of CR abnormalities, and their clinical correlates in adolescents with vertically-acquired human immunodeficiency virus (HIV) infection. Materials and methods: CRs of 75 patients [59 inpatients (33 males; mean age 13.7 {+-} 2.3 years) and 16 outpatients (eight males; mean age 14.1 {+-} 2.1 years)] were retrospectively reviewed by three independent observers. The overall extent of disease (to the nearest 5%), its distribution, and the proportional extents (totalling 100%) of different radiographic patterns (including ring/tramline opacities and consolidation) were quantified. CR features and clinical data were compared. Results: CRs were abnormal in 51/75 (68%) with 'extensive' disease in 38/51 (74%). Ring/tramline opacities and consolidation predominated (i.e., proportional extent >50%) in 26 and 21 patients, respectively. Consolidation was significantly more common in patients hospitalized primarily for a respiratory illness than patients hospitalized for a non-respiratory illness or in outpatients (p < 0.005, {chi}{sup 2} for trend); by contrast, ring/tramline opacities did not differ in prevalence across the groups. On stepwise logistic regression, predominant consolidation was associated with progressive dyspnoea [odds ratio (OR) 5.60; 95% confidence intervals (CI): 1.60, 20.1; p < 0.01] and was associated with a primary respiratory cause for hospital admission (OR: 22.0; CI: 2.7, 181.1; p < 0.005). Ring/tramline opacities were equally prevalent in patients with and without chronic symptoms and in those admitted to hospital with respiratory and non-respiratory illness. Conclusion: In HIV-infected adolescents, evaluated in secondary practice, CR abnormalities are prevalent. The presence of ring/tramline opacities, believed to reflect chronic airway disease, is not linked chronic respiratory symptoms.

  1. Screening strategies for tuberculosis prevalence surveys: the value of chest radiography and symptoms.

    Directory of Open Access Journals (Sweden)

    Anna H van't Hoog

    Full Text Available BACKGROUND: We conducted a tuberculosis (TB prevalence survey and evaluated the screening methods used in our survey, to assess if screening in TB prevalence surveys could be simplified, and to assess the accuracy of screening algorithms that may be applicable for active case finding. METHODS: All participants with a positive screen on either a symptom questionnaire, chest radiography (CXR and/or sputum smear microscopy submitted sputum for culture. HIV status was obtained from prevalent cases. We estimated the accuracy of modified screening strategies with bacteriologically confirmed TB as the gold standard, and compared these with other survey reports. We also assessed whether sequential rather than parallel application of symptom, CXR and HIV screening would substantially reduce the number of participants requiring CXR and/or sputum culture. RESULTS: Presence of any abnormality on CXR had 94% (95%CI 88-98 sensitivity (92% in HIV-infected and 100% in HIV-uninfected and 73% (95%CI 68-77 specificity. Symptom screening combinations had significantly lower sensitivity than CXR except for 'any TB symptom' which had 90% (95%CI 84-95 sensitivity (96% in HIV-infected and 82% in HIV-uninfected and 32% (95%CI 30-34 specificity. Smear microscopy did not yield additional suspects, thus the combined symptom/CXR screen applied in the survey had 100% (95%CI 97-100 sensitivity. Specificity was 65% (95%CI 61-68. Sequential application of first a symptom screen for 'any symptom', followed by CXR-evaluation and different suspect criteria depending on HIV status would result in the largest reduction of the need for CXR and sputum culture, approximately 36%, but would underestimate prevalence by 11%. CONCLUSION: CXR screening alone had higher accuracy compared to symptom screening alone. Combined CXR and symptom screening had the highest sensitivity and remains important for suspect identification in TB prevalence surveys in settings where bacteriological sputum

  2. Needle image plates compared to conventional CR in chest radiography: Is dose reduction possible?

    Energy Technology Data Exchange (ETDEWEB)

    Berger-Kulemann, Vanessa, E-mail: vanessa.berger-kulemann@meduniwien.ac.at [Department of Radiology, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna (Austria); Pötter-Lang, Sarah; Gruber, Michael [Department of Radiology, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna (Austria); Berger, Rudolf [Department of Internal Medicine II, Division of Cardiology, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna (Austria); Vonbank, Karin [Department of Internal Medicine II, Division of Pneumology, Medical University of Vienna Waehringer Guertel 18-20, 1090 Vienna (Austria); Weber, Michael [Department of Radiology, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna (Austria); Rabitsch, Werner [Department of Internal Medicine I, Bone Marrow Transplantation, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna (Austria); Uffmann, Martin [Department of Radiology, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna (Austria); Department of Radiology, KH Neunkirchen, Peischinger Straße 19, 2620 Neunkirchen (Austria)

    2012-12-15

    Purpose: To compare image quality of standard-dose computed radiography and dose reduced needle-technology CR for supine CXR in a clinical setting. Materials and methods: We prospectively evaluated 128 radiographs of 32 immunocompromised patients. For each patient four clinical CXR were performed within one week, two with powder image plates (PIP; Fuji ST-V) and two with needle image plates (NIP; Agfa DXS) at standard and half dose, respectively. One experienced radiologist and two residents blinded to dose level and kind of imaging system rated different anatomical structures, image noise, tubes/lines and abnormalities on a image quality scale from 1 to 10 (1 = poor, 10 = excellent). The rating scores were tested for statistical differences using analysis of variance with repeated measures. Results: A statistical difference (p < 0.05) was found for the two systems as well as for the two dose levels. Overall rating scores were 6.5 for PIP with full dose, 6.2 for PIP with half dose, 7.6 for NIP with full dose and 7.4 for NIP with half dose. There was a significant difference in favour of the NIP system at the same dose level. Also the NIP images obtained at half dose were ranked significantly better compared to the PIP images at standard dose. The differences in ranking of anatomical structures and abnormalities were more pronounced in low absorption areas (pulmonary vessels, parenchyma) than in high absorption areas (mediastinum, spine). Conclusion: For supine chest radiograms the NIP technology allows for a dose reduction of 50% while providing higher image quality.

  3. Time-series analysis of lung texture on bone-suppressed dynamic chest radiograph for the evaluation of pulmonary function: a preliminary study

    Science.gov (United States)

    Tanaka, Rie; Matsuda, Hiroaki; Sanada, Shigeru

    2017-03-01

    The density of lung tissue changes as demonstrated on imagery is dependent on the relative increases and decreases in the volume of air and lung vessels per unit volume of lung. Therefore, a time-series analysis of lung texture can be used to evaluate relative pulmonary function. This study was performed to assess a time-series analysis of lung texture on dynamic chest radiographs during respiration, and to demonstrate its usefulness in the diagnosis of pulmonary impairments. Sequential chest radiographs of 30 patients were obtained using a dynamic flat-panel detector (FPD; 100 kV, 0.2 mAs/pulse, 15 frames/s, SID = 2.0 m; Prototype, Konica Minolta). Imaging was performed during respiration, and 210 images were obtained over 14 seconds. Commercial bone suppression image-processing software (Clear Read Bone Suppression; Riverain Technologies, Miamisburg, Ohio, USA) was applied to the sequential chest radiographs to create corresponding bone suppression images. Average pixel values, standard deviation (SD), kurtosis, and skewness were calculated based on a density histogram analysis in lung regions. Regions of interest (ROIs) were manually located in the lungs, and the same ROIs were traced by the template matching technique during respiration. Average pixel value effectively differentiated regions with ventilatory defects and normal lung tissue. The average pixel values in normal areas changed dynamically in synchronization with the respiratory phase, whereas those in regions of ventilatory defects indicated reduced variations in pixel value. There were no significant differences between ventilatory defects and normal lung tissue in the other parameters. We confirmed that time-series analysis of lung texture was useful for the evaluation of pulmonary function in dynamic chest radiography during respiration. Pulmonary impairments were detected as reduced changes in pixel value. This technique is a simple, cost-effective diagnostic tool for the evaluation of regional

  4. DR静态平板去除错层伪影的研究%Research on Elimination of Truncation Artifacts with Digital Radiography Static Flat Panel

    Institute of Scientific and Technical Information of China (English)

    王克枢

    2016-01-01

    This paper researched the occasional truncation artifacts during the application of Shimadzu D-vision digital radiography (DR) photographic system. Through analysis of features of abnormal image and design features of the DR equipment, the research found out that truncation artifacts were directly caused by premature movement of the flat panel detector. Based on the finding, the research proposed a resolution plan in which a flat panel detector delay return control circuit was added. Clinical results showed that the flat panel detector delay return control circuit integrated with D-vision DR photographic system could eliminate truncation artifacts caused by flat panel detector motion and improve DR image quality without decreasing examination efficiency, which allowed the design to be used in the improvement of related equipments.%本文对岛津D-vision平板摄影透视系统偶发的图像错层伪影现象进行了研究,通过对异常图像和设备自身设计特点进行分析,发现曝光后平板的过早运动是导致图像伪影的直接原因,基于此提出了加配平板延时返回控制电路的解决方案。改进后结果表明,在平板摄影透视系统加装平板延时返回功能后,图像错层现象消失,DR摄影图像质量得到提升,且改进不会影响检查效率,可应用推广至相关设备的改进。

  5. Development of new imaging system for chest radiography; Investigation of basic imaging properties and improvement of signal detection

    Energy Technology Data Exchange (ETDEWEB)

    Higashida, Yoshiharu (Kumamoto Univ. (Japan). Coll. of Medical Science); Kariya, Kohmyo

    1991-09-01

    A new imaging system for chest radiography which has higher sensitivity in the mediastinum area than in the lung area has been developed. Through use of this new system for routine clinical examinations, the mediastinum area and lung areas are simultaneously displayed with a single exposure in optimal contrast. We investigated the fundamental physical properties of this system by comparing such items as its relative speed, modulation transfer functions (MTFs), density dependence on X-ray spectra, and low-contrast signal detections, with those of the conventional standard screen-film system. (author).

  6. Development of New Imaging System for Chest Radiography: Investigation of Basic Imaging Properties and Improvement of Signal Detection

    Science.gov (United States)

    Higashida, Yoshiharu; Kariya, Kohmyo

    1991-09-01

    A new imaging system for chest radiography which has higher sensitivity in the mediastinum area than in the lung area has been developed. Through use of this new system for routine clinical examinations, the mediastinum area and lung areas are simultaneously displayed with a single exposure in optimal contrast. We investigated the fundamental physical properties of this system by comparing such items as its relative speed, modulation transfer functions (MTFs), density dependence on X-ray spectra, and low-contrast signal detections, with those of the conventional standard screen-film system.

  7. Analysis of image quality according to BMI of digital chest radiography: Focusing on bureau of radiological health evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Seong Jin [Gammaknife center, Inje University Haeundae Paik Hospital, Busan (Korea, Republic of); Im, In Chul [Dept. of Radiological Science, Dongeui University, Busan (Korea, Republic of); Cho, Ji Hwan [Dept. of Health Care Clinic, Inje University Busan Paik Hospital, Busan (Korea, Republic of)

    2017-03-15

    Visual evaluation of chest radiograph images is the most practical and effective method. This study compared the Body Mass Index, waist circumference, and mAs with chest radiographs of 351 women. The Bureau of Radiological Health method was used to evaluate the image quality of chest X-ray images by anatomical and physical methods. The average age of the subjects was 30.17±4.73 and the average waist circumference was 66.91±4.67 cm. The mean Body Mass Index value was 20.21±2.23, the mean value of mAs was 3.04±0.78, and the mean value of Bureau of Radiological Health was 79.83±8.45. When the Body Mass Index value increased, waist circumference and mAs mean value increased. The mean value of Body Mass Index was statistically significant(p<0.05) in Group 4 compared to Groups 1 and 2, with increasing Body Mass Index. Exposure control of the automatic exposure control system is considered to be well performed according to body thickness or Body Mass Index at the time of chest radiography. As the Body Mass Index increases, the thickness of the body increases and the breast thickness of the woman also increases. Therefore, it is considered that the exposure amount is changed by the automatic exposure control device to affect the image quality.

  8. Three-contrast, metal test pattern (Snellen E-plate) in evaluation of imaging techniques in clinical chest radiography

    Energy Technology Data Exchange (ETDEWEB)

    Manninen, H.

    A metal test pattern based on a minified Snellen-type E-plate was evaluated in testing six imaging techniques for chest radiography. The device consisted of three contrast zones and it was attached to the patient's back over the right lung during chest radiography. The values for visual detectability of the E-figures were compared with the film scores obtained by grading the radiographs with respect to visibility of diagnostically important anatomic details. The test plate proved to be a simple, quick and reproducible tool for testing several imaging techniques at the same time. The E-plate results were similar to those of the visual grading analysis in most respects. A few discrepancies existed, which were probably due to the inability of the test pattern to fully consider the effect of motion unsharpness and varying scattering conditions within the human thorax, as well as to great differences in roentgen ray absorption properties between Au and tissues. (orig.).

  9. Comparison of visual grading analysis and determination of detective quantum efficiency for evaluating system performance in digital chest radiography

    Energy Technology Data Exchange (ETDEWEB)

    Sund, Patrik; Baath, Magnus; Maansson, Lars Gunnar [Department of Radiation Physics, Goeteborg University, 41345 Goeteborg (Sweden); Department of Medical Physics and Biomedical Engineering, Sahlgrenska University Hospital, 41345 Goeteborg (Sweden); Kheddache, Susanne [Department of Radiology, Goeteborg University, 41345 Goeteborg (Sweden); Department of Radiology, Sahlgrenska University Hospital, 41345 Goeteborg (Sweden)

    2004-01-01

    A study was conducted to compare physical and clinical system performance in digital chest radiography. Four digital X-ray modalities, two storage-phosphor based systems and two generations of a CCD-based system, were evaluated in terms of both their imaging properties (determination of presampling MTF and DQE) and clinical image quality (grading of the reproduction of anatomical details of 23 healthy volunteers using both absolute and relative visual grading analysis). One of the two storage-phosphor systems performed best in both evaluations and the first generation of the CCD-based system was rated worst; however, the other two systems were ranked differently with the two methods. The newest CCD-based system yielded a higher clinical image quality than the second storage-phosphor system, although the latter presented a DQE substantially higher than the former. The results show that clinical performance cannot be predicted from determinations of DQE alone, and that a system with lower DQE, under the quantum-saturated conditions in chest radiography, can outperform a system with higher DQE if the image processing used on the former is more effective in presenting the information in the image to the radiologist. (orig.)

  10. Evaluation of the effective detective quantum efficiency for various tube voltages with digital radiography for chest imaging

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Hyo-Min; Kim, Hee-Joung; Park, Hye-Suk; Kim, Dae-Hong; Lee, Chang-Lae; Choi, Yu-Na; Lee, Seung-Wan [Yonsei University, Wonju (Korea, Republic of)

    2011-03-15

    The concept of effective detective quantum efficiency (eDQE) has recently been developed and introduced. The purpose of this study was to use the eDQE to evaluate the effect of tube voltage and grid for chest imaging with a direct flat-panel-based digital radiographic system. The exposure factors that we considered were the tube potential and an anti-scatter moving grid. The incident air kerma was adjusted for each tube potential to yield an effective dose of 34 {mu}Sv. The scatter fraction (SF), transmission fraction (TF), effective modulation transfer function (eMTF), and effective normalized noise power spectrum (eNNPS) were measured using a phantom that simulate the attenuation and scatter properties of the human chest. Our results showed that the resolution properties measured by using eMTFs were independent of the tube potential regardless of whether or not a grid was used. The noise properties through the phantom were greater with the use of an anti-scatter grid than without while the eDQE was largest at a lower tube potential, which we tested without a grid. In conclusion, we measured a high efficiency at a low tube potential without an anti-scatter grid for digital radiography (DR) in chest imaging. The eDQE reflected the real exam environment better than the general DQE because it better reflected the effect of the total X-ray system.

  11. Survey of the Satisfaction and Dissatisfaction of Referring Physicians Concerning the Radiologic Report of Plain Radiography Except for Chest Plain Radiography

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Soon Young; Park, Noh Hyuck; Kim, Mi Sung; Park, Chan Sub; Park, Ji Yeon [Dept. of Radiology, Myongji Hospital, Kwandong University College of Medicine, Goyang (Korea, Republic of); Park, Hee Jin [Dept. of Radiology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Kim, Sam Soo [Dept. of Radiology, Kangwon National University School of Medicine, Chuncheon (Korea, Republic of); Jeon, Hyun Jun [Dept. of Occupational Medicine, Dongsan Medical Center, Keimyung University School of Medicine, Daegu (Korea, Republic of)

    2011-09-15

    To assess the satisfaction, attitude, dissatisfaction and general opinion of radiologic reports on the plain radiography, except for chest plain radiographs. A questionnaire was distributed to the 63 physicians of our hospital. The questionnaire aimed to investigate physician's general attitude, dissatisfaction and opinions. The responses elicited, as well as discrepancies among residents, staff, medical clinicians and surgical clinicians were assessed. Chi-square and t-tests were used to determine the value of the data. The mean rate of satisfaction for the reading report by medical clinicians (64%) was higher than surgical clinicians (25%) (p < 0.001). The mean satisfaction score was 3.1 (2.8-3.61). The main cause for dissatisfaction was the absence of reports when they were needed, especially for residents. The medical clinician's dependence on radiologic reports was higher than that of the surgical clinicians. The satisfaction score was in the middle range and the main cause of dissatisfaction was absence of the reports when they were needed.

  12. The relationship of over density to overexposure each film/screen systems in chest radiography

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jung Min; Huo Joon [Korea University, Seoul (Korea, Republic of); Taro, Hayash; Yuji, Ishida; Tatsuya, Sakurai [The Chemotherapeutic Istitute Hospital, Tokyo (Japan)

    1999-06-01

    This study is to calculate the exposed radiation dose using Bit method, NDD calculation method and monogram method without dosimeter. In addition,we can calculate the radiation dose from x-ray film density as a film badge. The authors examined the entrance skin dose from 2 {approx} 3 intercostal chest x-ray film density. We also studied the relationship between film density and equivalent dose in the each screen film system under the different radiation quality and the poor geometry condition of grid ratio. As results, we established the deductive method to define the entrance skin dose from chest x-ray film density. The error range was found in the range -13 percent {approx} +17 percent for between deductive entrance skin dose and the 2 {approx} 3 inter coastal chest x-ray film density to actual detective radiation dose with dosimeter. (author)

  13. Survey of the Use of X-ray Beam Collimator and Shielding Tools during Infant Chest Radiography

    Directory of Open Access Journals (Sweden)

    Vahid Karami

    2016-04-01

    Full Text Available Background The use of shielding tools and X-ray beam collimator has extensively been advocated as effective methods to reduce radiation exposure to patients underwent radiological procedures. The aim of this study was to address the use of these protection measures during infant chest radiography. Material and Methods 348digital and/or analogue infant chest radiographs were reviewed that performed between October-  and December 2015 at four main hospitals of Khuzestan-Iran province to assessment the beam collimation. For each radiograph the area between current and acceptable collimation was calculated. Thirty eight radiographers were deeply interviewed to investigate the actual use of shielding tools and the main reasons for not using of them. Results Only 54 (15.5% radiographs [33(61% analogues and 21(39% digital] have satisfactory collimation. The total means area of diagnostic interest (ADI and the region outside ADI for each radiograph was estimated 171 and 86 cm2, respectively. The irradiated region outside the ADI was significantly larger in digital than in analogue images (mean of 103 cm2 vs. 54 cm2; P < 0.05. Shielding tools were used regularly only by 5% of radiographers. Conclusion The radiosensitive organs of infants located outside of ADI in hospitals investigated are at risk. Adherence to safety guideline urgently recommends.

  14. Lung ultrasound versus chest radiography for the diagnosis of pneumothorax in critically ill patients: A prospective, single-blind study

    Directory of Open Access Journals (Sweden)

    W Abdalla

    2016-01-01

    Full Text Available Background: Radiologic data remains the gold standard for the diagnosis of pneumothorax (PTX. The use of ultrasonography (US has recently emerged as the method of choice with physicians who can perform bedside US. Purpose: To compare the diagnostic accuracy of lung US against bedside chest radiography (CR for the detection of PTX using thoracic computed tomography (CT as the gold standard. Materials and Methods: We conducted a prospective, single-blind study on 192 critically ill patients; each patient received lung US examination, bedside CR, followed by thoracic CT scan searching for PTX. Results: Of the studied patients, CT of the chest confirmed the diagnosis of PTX in 36 (18.75% patients of which 31 were diagnosed by thoracic US while CR detected only 19 cases. Overall lung US showed a considerable higher sensitivity than bedside CR (86.1% vs. 52.7%, lung US also showed higher, negative predictive values, and diagnostic accuracy against CR (96.8% vs. 90.1%, and (95.3% vs. 90.6%, respectively. CR had a slightly higher specificity than lung US (99.4% vs. 97.4%, and higher positive predictive values (95.0% vs. 88.6%. Conclusion: Lung US is an accurate modality more than anteroposterior bedside CR in comparison with CT scanning when evaluating critically ill mechanically ventilated patients, patients underwent thoracocentesis, central venous catheter insertion, or patients with polytrauma.

  15. Comparison of Computed Tomography and Chest Radiography in the Detection of Rib Fractures in Abused Infants

    Science.gov (United States)

    Wootton-Gorges, Sandra L.; Stein-Wexler, Rebecca; Walton, John W.; Rosas, Angela J.; Coulter, Kevin P.; Rogers, Kristen K.

    2008-01-01

    Purpose: Chest radiographs (CXR) are the standard method for evaluating rib fractures in abused infants. Computed tomography (CT) is a sensitive method to detect rib fractures. The purpose of this study was to compare CT and CXR in the evaluation of rib fractures in abused infants. Methods: This retrospective study included all 12 abused infants…

  16. Detection of tuberculosis with digital chest radiography: automatic reading versus interpretation by clinical officers

    NARCIS (Netherlands)

    Maduskar, P.; Muyoyeta, M.; Ayles, H.; Hogeweg, L.E.; Peters-Bax, L.; Ginneken, B. van

    2013-01-01

    SETTING: A busy urban health centre in Lusaka, Zambia. OBJECTIVE: To compare the accuracy of automated reading (CAD4TB) with the interpretation of digital chest radiograph (CXR) by clinical officers for the detection of tuberculosis (TB). DESIGN: A retrospective analysis was performed on 161

  17. Sensitivity and specificity of perfusion scintigraphy combined with chest radiography for acute pulmonary embolism in PIOPED II.

    Science.gov (United States)

    Sostman, H Dirk; Miniati, Massimo; Gottschalk, Alexander; Matta, Fadi; Stein, Paul D; Pistolesi, Massimo

    2008-11-01

    We used the archived Prospective Investigation of Pulmonary Embolism Diagnosis II (PIOPED II) data and images to test the hypothesis that reading perfusion scans with chest radiographs but without ventilation scans, and categorizing the perfusion scan as "pulmonary embolism (PE) present" or "PE absent," can result in clinically useful sensitivity and specificity in most patients. Patients recruited into PIOPED II were eligible for the present study if they had a CT angiography (CTA) or digital subtraction angiography (DSA) diagnosis, an interpretable perfusion scan and chest radiographs, and a Wells' score. Four readers reinterpreted the perfusion scans and chest radiographs of eligible patients. Two readers used the modified PIOPED II criteria and 2 used the Prospective Investigative Study of Pulmonary Embolism Diagnosis (PISAPED) criteria. The chest radiographs were read as "normal/near normal," "abnormal," or "nondiagnostic," and the perfusion scans were read as "PE present," "PE absent," or "nondiagnostic." The primary analysis used a composite reference standard: the PIOPED II DSA result or, if there was no definitive DSA result, CTA results that were concordant with the Wells' score as defined in PIOPED II (CTA positive and Wells' score > 2, or CTA negative and Wells' score PIOPED II criteria, the sensitivity of a "PE present" perfusion scan was 84.9% (95% confidence interval [CI], 80.1%-88.8%), and the specificity of "PE absent" was 92.7% (95% CI, 91.1%-94.1%), excluding "nondiagnostic" results, which occurred in 20.6% (95% CI, 18.8%-22.5%). Using PISAPED criteria, the sensitivity of a "PE present" perfusion scan was 80.4% (95% CI, 75.9%-84.3%) and the specificity of "PE absent" was 96.6% (95% CI, 95.5%-97.4%), whereas the proportion of patients with "nondiagnostic" scans was 0% (95% CI, 0.0%-0.2%). Perfusion scintigraphy combined with chest radiography can provide diagnostic accuracy similar to both CTA and ventilation-perfusion scintigraphy, at lower cost

  18. Application of off-line image processing for optimization in chest computed radiography using a low cost system.

    Science.gov (United States)

    Muhogora, Wilbroad E; Msaki, Peter; Padovani, Renato

    2015-03-08

     The objective of this study was to improve the visibility of anatomical details by applying off-line postimage processing in chest computed radiography (CR). Four spatial domain-based external image processing techniques were developed by using MATLAB software version 7.0.0.19920 (R14) and image processing tools. The developed techniques were implemented to sample images and their visual appearances confirmed by two consultant radiologists to be clinically adequate. The techniques were then applied to 200 chest clinical images and randomized with other 100 images previously processed online. These 300 images were presented to three experienced radiologists for image quality assessment using standard quality criteria. The mean and ranges of the average scores for three radiologists were characterized for each of the developed technique and imaging system. The Mann-Whitney U-test was used to test the difference of details visibility between the images processed using each of the developed techniques and the corresponding images processed using default algorithms. The results show that the visibility of anatomical features improved significantly (0.005 ≤ p ≤ 0.02) with combinations of intensity values adjustment and/or spatial linear filtering techniques for images acquired using 60 ≤ kVp ≤ 70. However, there was no improvement for images acquired using 102 ≤ kVp ≤ 107 (0.127 ≤ p ≤ 0.48). In conclusion, the use of external image processing for optimization can be effective in chest CR, but should be implemented in consultations with the radiologists.

  19. Pacemakers and implantable cardioverter defibrillators, unknown to chest radiography: Review, complications and systematic reading

    Energy Technology Data Exchange (ETDEWEB)

    Alandete Germán, Salvador Pascual, E-mail: salaiger@gmail.com; Isarria Vidal, Santiago, E-mail: isarria@comv.es; Domingo Montañana, María Luisa, E-mail: domingo.luimon@gmail.com; De la vía Oraá, Esperanza, E-mail: esviao82@gmail.com; Vilar Samper, José, E-mail: vilarsamper@gmail.com

    2015-03-15

    Highlights: •Radiologists have an important function in the evaluation of these devices. •We revise their radiological appearances and possible complications. •The knowledge in normal aspects and complications is important for radiologist. •To ensure an accurate reading of the chest x-ray, we present a systematic approach. -- Abstract: Chest X-ray is the imaging technique of choice for an initial study of pacemakers and implantable cardio-defibrillators (ICD). Radiologists have an important role in the evaluation of its initial placement and in the assessment during its follow-up. For this reason, it is necessary to know not only the different existing devices and its components but also the reasons of malfunction or possible complications. The purpose of this article is to do a systematic review of the different types of pacemakers and ICD. We review their usual radiological appearances, the possible complications which might take place and its causes of malfunctioning.

  20. Measurement of entrance skin dose and estimation of organ dose during pediatric chest radiography.

    Science.gov (United States)

    Kumaresan, M; Kumar, Rajesh; Biju, K; Choubey, Ajay; Kantharia, S

    2011-06-01

    Entrance skin dose (ESD) was measured to calculate the organ doses from the anteroposterior (AP) and posteroanterior (PA) chest x-ray projections for pediatric patients in an Indian hospital. High sensitivity tissue-equivalent thermoluminescent dosimeters (TLD, LiF: Mg, Cu, P chips) were used for measuring entrance skin dose. The respective organ doses were calculated using the Monte Carlo method (MCNP 3.1) to simulate the examination set-up and a three-dimensional mathematical phantom for representing an average 5-y-old Indian child. Using this method, conversion coefficients were derived for translating the measured ESD to organ doses. The average measured ESDs for the chest AP and PA projections were 0.305 mGy and 0.171 mGy, respectively. The average calculated organ doses in the AP and the PA projections were 0.196 and 0.086 mSv for the thyroid, 0.167 and 0.045 mSv for the trachea, 0.078 and 0.043 mSv for the lungs, 0.110 and 0.013 mSv for the liver, 0.002 and 0.016 mSv for the bone marrow, 0.024 and 0.002 mSv for the kidneys, and 0.109 and 0.023 mSv for the heart, respectively. The ESD and organ doses can be reduced significantly with the proper radiological technique. According to these results, the chest PA projection should be preferred over the AP projection in pediatric patients. The estimated organ doses for the chest AP and PA projections can be used for the estimation of the associated risk.

  1. Dose reduction of radiographs of the pediatric pelvis for diagnosing hip dysplasia using a digital flat-panel detector system; Dosisreduktion bei Roentgenaufnahmen des kindlichen Beckenskelettes zur Diagnostik der Hueftgelenksdysplasie unter Verwendung eines digitalen Flachdetektorsystems

    Energy Technology Data Exchange (ETDEWEB)

    Ludwig, K.; Ahlers, K.; Kloska, S.; Vieth, V.; Meier, N.; Heindel, W. [Inst. fuer Klinische Radiologie, Westfaelische Wilhelms-Univ. Muenster (Germany); Sandmann, C.; Gosheger, G. [Orthopaedische Klinik, Westfaelische Wilhelms-Univ. Muenster (Germany)

    2003-01-01

    Purpose: To evaluate a possible dose reduction in pediatric pelvic radiographs in congenital hip dysplasia using a digital flat-panel system instead of a phosphor-storage system. Materials and Methods: During a six-month period, all pediatric patients referred for pelvic radiography for the evaluation of congenital hip dysplasia were randomely assigned to be examined by either a phosphor-storage system or a digital flat-panel system, whereby the latter system was operated with half the radiation dose. Thirty pairs of radiographs were assessed for the visibility of 16 anatomic details and for 5 orthopedic-radiographic measurements (5-point scale with 1 = excellent; three independent observers). The projection indices of Ball and Kommenda and of Toennis and Brunken were calculated for all radiographs. The Student's t-test was used to compare the flat-panel and the phosphor-storage radiographs for observers' assessments, patients' age and projection indices. Results: In a total of 7560 observations, the scores for the visibility of anatomic details and orthopedic-radiographic measurements were respectively 2.72 and 2.64 for the flat-panel system and 2.93 and 2.79 for the phosphor-storage system. No significant differences were found between both systems (p > 0.05) and between patient age and projection indices (p > 0.05). Conclusion: Pediatric pelvic radiographs can be obtained with a digital flat-panel system using half the radiation dose instead of a phosphor-storage system without sacrificing relevant information in the diagnosis of congenital hip dysplasia. (orig.) [German] Zielsetzung: Evaluation einer moeglichen Dosisreduktion bei kindlichen Beckenroentgenaufnahmen zur Diagnostik der Hueftgelenksdysplasie mit einem digitalen Flachdetektorsystem im Vergleich zu einem digitalen Speicherfoliensystem. Material und Methoden: Prospektiv wurden alle ueber einen Zeitraum von 6 Monaten zur Roentgenaufnahme des Beckenskelettes im Rahmen der Diagnostik der

  2. Computerized Classification of Pneumoconiosis on Digital Chest Radiography Artificial Neural Network with Three Stages.

    Science.gov (United States)

    Okumura, Eiichiro; Kawashita, Ikuo; Ishida, Takayuki

    2017-01-20

    It is difficult for radiologists to classify pneumoconiosis from category 0 to category 3 on chest radiographs. Therefore, we have developed a computer-aided diagnosis (CAD) system based on a three-stage artificial neural network (ANN) method for classification based on four texture features. The image database consists of 36 chest radiographs classified as category 0 to category 3. Regions of interest (ROIs) with a matrix size of 32 × 32 were selected from chest radiographs. We obtained a gray-level histogram, histogram of gray-level difference, gray-level run-length matrix (GLRLM) feature image, and gray-level co-occurrence matrix (GLCOM) feature image in each ROI. For ROI-based classification, the first ANN was trained with each texture feature. Next, the second ANN was trained with output patterns obtained from the first ANN. Finally, we obtained a case-based classification for distinguishing among four categories with the third ANN method. We determined the performance of the third ANN by receiver operating characteristic (ROC) analysis. The areas under the ROC curve (AUC) of the highest category (severe pneumoconiosis) case and the lowest category (early pneumoconiosis) case were 0.89 ± 0.09 and 0.84 ± 0.12, respectively. The three-stage ANN with four texture features showed the highest performance for classification among the four categories. Our CAD system would be useful for assisting radiologists in classification of pneumoconiosis from category 0 to category 3.

  3. Aspects of radiation protection during chest X-radiography; Strahlenhygienische Aspekte bei der Roentgenuntersuchung des Thorax

    Energy Technology Data Exchange (ETDEWEB)

    Seidenbusch, M.C.; Schneider, K. [Dr. von Haunersches Kinderspital, Klinikum der Universitaet Muenchen, Institut fuer Klinische Radiologie - Kinderradiologie, Muenchen (Germany)

    2015-07-15

    Radiation safety in conventional X-ray diagnostics is based on the concepts of justification, optimization of an X-ray examination and limitation of the radiation exposure achieved during the examination. Optimization of an X-ray examination has to be considered as a multimodal process in which all technical components of the X-ray equipment have to be adapted to each other and also have to be adapted to the anthropometric characteristics of patients and the clinical indications. In this article the technical components of a conventional pediatric chest X-radiograph are presented, and recommendations for optimizing chest X-rays in children are provided. The following measures are of prime importance: correct x-ray beam limitation, using the posteroanterior projection when possible and not using anti-scatter grids in children under approximately 8 years old. In pediatric radiology chest x-rays that are taken not at the peak of inspiration can also be of some diagnostic significance. Optimization of an X-ray examination inevitably results in the limitation of radiation exposure. (orig.) [German] Die Strahlenhygiene in der konventionellen radiologischen Diagnostik basiert auf der Trias Rechtfertigung, Optimierung bzw. Limitierung der Roentgenuntersuchung bzw. Strahlenexposition. Die Optimierung einer Roentgenuntersuchung ist als multimodaler Prozess aufzufassen, in welchem saemtliche technische Komponenten der Roentgeneinrichtung sowohl miteinander als auch mit den anthropometrischen Eigenschaften des Patienten und der klinischen Fragestellung abzustimmen sind. Im vorliegenden Beitrag werden die technischen Komponenten bei der konventionellen Roentgenuntersuchung des paediatrischen Thorax in ihrer Beziehung zueinander dargestellt und Empfehlungen fuer eine Optimierung der konventionellen Thoraxaufnahme bei Kindern ausgesprochen. Die wichtigsten Massnahmen bestehen in einer korrekten Einblendung, in der Anfertigung der Aufnahmen im posteroanterioren Strahlengang und im

  4. Bone marrow dose in chest radiography: the posteroanterior vs. anteroposterior projection

    Energy Technology Data Exchange (ETDEWEB)

    Archer, B.R.; Whitmore, R.C.; North, L.B.; Bushong, S.C.

    1979-10-01

    The dose to active bone marrow resulting from anteroposterior (AP) and posteroanterior (PA) chest examinations was estimated using an Alderson Rando phantom and extruded lithium fluoride dosimeters. The AP projections resulted in a mean marrow dose range of 1.9 to 2.6 mrad (0.019 to 0.026 mGy) as compared to doses for PA projections of 3.4 to 3.8 mrad (0.034 to 0.038 mGy) for optimally diagnostic exposures taken at 70, 90, and 120 kVp.

  5. Is HELICS the right way? Lack of chest radiography limits ventilator-associated pneumonia surveillance in Wales

    Directory of Open Access Journals (Sweden)

    Richard Pugh

    2016-08-01

    Full Text Available Introduction: The reported incidence of ventilator-associated pneumonia (VAP in Wales is low compared with surveillance data from other European regions. It is unclear whether this reflects success of the Welsh healthcare-associated infection prevention measures or limitations in the application of European VAP surveillance methods. Our primary aim was to investigate episodes of ventilator-associated respiratory tract infection (VARTI, to identify episodes that met established criteria for VAP, and to explore reasons why others did not, according to the Hospitals in Europe Link for Infection Control through Surveillance (HELICS definitions. Materials and methods: During two 14-day study periods 2012-2014, investigators reviewed all invasively ventilated patients in all 14 Welsh Intensive Care Units (ICUs. Episodes were identified in which the clinical team had commenced antibiotic therapy because of suspected VARTI. Probability of pneumonia was estimated using a modified Clinical Pulmonary Infection Score (mCPIS. Episodes meeting HELICS definitions of VAP were identified, and reasons for other episodes not meeting definitions examined. In the second period, each patient was also assessed with regards to the development of a ventilator-associated event (VAE, according to recent US definitions. Results: The study included 306 invasively ventilated patients; 282 were admitted to ICU for 48 hours or more. 32 (11.3% patients were commenced on antibiotics for suspected VARTI. 10 of these episodes met HELICS definitions of VAP, an incidence of 4.2 per 1000 intubation days. In 48% VARTI episodes, concurrent chest radiography was not performed, precluding the diagnosis of VAP. Mechanical ventilation (16.0 vs. 8.0 days; p=0.01 and ICU stay (25.0 vs. 11.0 days; p=0.01 were significantly longer in patients treated for VARTI compared to those not treated. There was no overlap between episodes of VARTI and of VAE. Discussion: HELICS VAP surveillance

  6. The value of digital tomosynthesis of the chest as a problem-solving tool for suspected pulmonary nodules and hilar lesions detected on chest radiography

    Energy Technology Data Exchange (ETDEWEB)

    Galea, Angela, E-mail: galeaangie@gmail.com [Peninsula Radiology Academy, William Prance Road, Plymouth PL65WR (United Kingdom); Dubbins, Paul, E-mail: Paul.dubbins@nhs.net [Plymouth Hospital NHS Trust, Plymouth PL68DH (United Kingdom); Riordan, Richard, E-mail: richardriordan@nhs.net [Plymouth Hospital NHS Trust, Plymouth PL68DH (United Kingdom); Adlan, Tarig, E-mail: tarig.adlan@nhs.net [Plymouth Hospital NHS Trust, Plymouth PL68DH (United Kingdom); Roobottom, Carl, E-mail: carl.roobotoom@nhs.net [Plymouth Hospital NHS Trust, Plymouth PL68DH (United Kingdom); Gay, David, E-mail: davegay@nhs.net [Plymouth Hospital NHS Trust, Plymouth PL68DH (United Kingdom)

    2015-05-15

    Graphical abstract: When compared to CXR, DTS has: • Superior resolution • Better assessment of location in the AP dimension (better at locating a pleural or intrapulmonary lesion) • Better characterisation (better at distinguishing between calcified plaque and soft tissue) • Removes composite artefact caused by overlying anatomical structures (such as the ribs or pulmonary vessels) DTS has improved sensitivity, specificity and accuracy when compared to CXR. - Highlights: • DTS is a type of limited angle tomography. Sixty coronal reconstructed images of the chest are produced that combine the superior resolution of radiography with the tomographic benefits of computed tomography. • The sensitivity for detecting a suspected lung lesions is 0.65 with CXR and 0.91 for DTS. • The high specificity of DTS (1) and the high negative predictive value (0.94) are similar to CT and suggest that if the DTS is normal patients do not need further assessment with CT with significant potential dose savings. • 50% of suspected lesions were resolved with CXR, this improved to 96% with DTS. - Abstract: Objectives: To assess the capability of digital tomosynthesis (DTS) of the chest compared to a postero-anterior (PA) and lateral chest radiograph (CXR) in the diagnosis of suspected but unconfirmed pulmonary nodules and hilar lesions detected on a CXR. Computed tomography (CT) was used as the reference standard. Materials and method: 78 patients with suspected non-calcified pulmonary nodules or hilar lesions on their CXR were included in the study. Two radiologists, blinded to the history and CT, prospectively analysed the CXR (PA and lateral) and the DTS images using a picture archiving and communication workstation and were asked to designate one of two outcomes: true intrapulmonary lesion or false intrapulmonary lesion. A CT of the chest performed within 4 weeks of the CXR was used as the reference standard. Inter-observer agreement and time to report the modalities

  7. An artificial neural network for estimating scatter exposures in portable chest radiography.

    Science.gov (United States)

    Lo, J Y; Floyd, C E; Baker, J A; Ravin, C E

    1993-01-01

    An adaptive linear element (Adaline) was developed to estimate the two-dimensional scatter exposure distribution in digital portable chest radiographs (DPCXR). DPCXRs and quantitative scatter exposure measurements at 64 locations throughout the chest were acquired for ten radiographically normal patients. The Adaline is an artificial neural network which has only a single node and linear thresholding. The Adaline was trained using DPCXR-scatter measurement pairs from five patients. The spatially invariant network would take a portion of the image as its input and estimate the scatter content as output. The trained network was applied to the other five images, and errors were evaluated between estimated and measured scatter values. Performance was compared against a convolution scatter estimation algorithm. The network was evaluated as a function of network size, initial values, and duration of training. Network performance was evaluated qualitatively by the correlation of network weights to physical models, and quantitatively by training and evaluation errors. Using DPCXRs as input, the network learned to describe known scatter exposures accurately (7% error) and estimate scatter in new images (< 8% error) slightly better than convolution methods. Regardless of size and initial shape, all networks adapted into radial exponentials with magnitude of 0.75, perhaps implying an ideal point spread function and average scatter fraction, respectively. To implement scatter compensation, the two-dimensional scatter distribution estimated by the neural network is subtracted from the original DPCXR.

  8. High-resolution computed tomography in silicosis: correlation with chest radiography and pulmonary function tests

    Energy Technology Data Exchange (ETDEWEB)

    Lopes, Agnaldo Jose [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Pedro Ernesto Univ. Hospital. Dept. of Respiratory Function]. E-mail: phel.lop@uol.com.br; Mogami, Roberto; Capone, Domenico; Jansen, Jose Manoel [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). School of Medical Sciences; Tessarollo, Bernardo [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Dept. of Radiology and Diagnostic Image; Melo, Pedro Lopes de [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Inst. of Biology

    2008-05-15

    Objective: To correlate tomographic findings with pulmonary function findings, as well as to compare chest X-ray findings with high-resolution computed tomography (HRCT) findings, in patients with silicosis. Methods: A cross-sectional study was conducted in 44 non-smoking patients without a history of tuberculosis. Chest X-ray findings were classified according to the International Labour Organization recommendations. Using a semiquantitative system, the following HRCT findings were measured: the full extent of pulmonary involvement; parenchymal opacities; and emphysema. Spirometry and forced oscillation were performed. Pulmonary volumes were evaluated using the helium dilution method, and diffusing capacity of the lung for carbon monoxide was assessed. Results: Of the 44 patients studied, 41 were male. The mean age was 48.4 years. There were 4 patients who were classified as category 0 based on X-ray findings and as category 1 based on HRCT findings. Using HRCT scans, we identified progressive massive fibrosis in 33 patients, compared with only 23 patients when X-rays were used. Opacity score was found to correlate most closely with airflow, DLCO and compliance. Emphysema score correlated inversely with volume, DLCO and airflow. In this sample of patients presenting a predominance of large opacities (75% of the individuals), the deterioration of pulmonary function was associated with the extent of structural changes. Conclusions: In the early detection of silicosis and the identification of progressive massive fibrosis, HRCT scans are superior to X-rays. (author)

  9. An evaluation of automated chest radiography reading software for tuberculosis screening among public- and private-sector patients.

    Science.gov (United States)

    Rahman, Md Toufiq; Codlin, Andrew J; Rahman, Md Mahfuzur; Nahar, Ayenun; Reja, Mehdi; Islam, Tariqul; Qin, Zhi Zhen; Khan, Md Abdus Shakur; Banu, Sayera; Creswell, Jacob

    2017-05-01

    Computer-aided reading (CAR) of medical images is becoming increasingly common, but few studies exist for CAR in tuberculosis (TB). We designed a prospective study evaluating CAR for chest radiography (CXR) as a triage tool before Xpert MTB/RIF (Xpert).Consecutively enrolled adults in Dhaka, Bangladesh, with TB symptoms received CXR and Xpert. Each image was scored by CAR and graded by a radiologist. We compared CAR with the radiologist for sensitivity and specificity, area under the receiver operating characteristic curve (AUC), and calculated the potential Xpert tests saved.A total of 18 036 individuals were enrolled. TB prevalence by Xpert was 15%. The radiologist graded 49% of CXRs as abnormal, resulting in 91% sensitivity and 58% specificity. At a similar sensitivity, CAR had a lower specificity (41%), saving fewer (36%) Xpert tests. The AUC for CAR was 0.74 (95% CI 0.73-0.75). CAR performance declined with increasing age. The radiologist grading was superior across all sub-analyses.Using CAR can save Xpert tests, but the radiologist's specificity was superior. Differentiated CAR thresholds may be required for different populations. Access to, and costs of, human readers must be considered when deciding to use CAR software. More studies are needed to evaluate CAR using different screening approaches. Copyright ©ERS 2017.

  10. Analysis of the impact of digital tomosynthesis on the radiological investigation of patients with suspected pulmonary lesions on chest radiography

    Energy Technology Data Exchange (ETDEWEB)

    Quaia, Emilio; Baratella, Elisa; Cernic, Stefano; Lorusso, Arianna; Casagrande, Federica; Cioffi, Vincenzo; Cova, Maria Assunta [University of Trieste (Italy), Department of Radiology, Cattinara Hospital, Trieste (Italy)

    2012-09-15

    To assess the impact of digital tomosynthesis (DTS) on the radiological investigation of patients with suspected pulmonary lesions on chest radiography (CXR). Three hundred thirty-nine patients (200 male; age, 71.19 {+-} 11.9 years) with suspected pulmonary lesion(s) on CXR underwent DTS. Two readers prospectively analysed CXR and DTS images, and recorded their diagnostic confidence: 1 or 2 = definite or probable benign lesion or pseudolesion deserving no further diagnostic workup; 3 = indeterminate; 4 or 5 = probable or definite pulmonary lesion deserving further diagnostic workup by computed tomography (CT). Imaging follow-up by CT (n = 76 patients), CXR (n = 256) or histology (n = 7) was the reference standard. DTS resolved doubtful CXR findings in 256/339 (76 %) patients, while 83/339 (24 %) patients proceeded to CT. The mean interpretation time for DTS (mean {+-} SD, 220 {+-} 40 s) was higher (P < 0.05; Wilcoxon test) than for CXR (110 {+-} 30 s), but lower than CT (600 {+-} 150 s). Mean effective dose was 0.06 mSv (range 0.03-0.1 mSv) for CXR, 0.107 mSv (range 0.094-0.12 mSv) for DTS, and 3 mSv (range 2-4 mSv) for CT. DTS avoided the need for CT in about three-quarters of patients with a slight increase in the interpretation time and effective dose compared to CXR. (orig.)

  11. Advantages and pitfalls of pocket ultrasound vs daily chest radiography in the coronary care unit: A single-user experience.

    Science.gov (United States)

    Phillips, Colin T; Manning, Warren J

    2017-05-01

    Pocket ultrasonography may enhance patient diagnosis and care. We sought to assess pocket ultrasound in detecting common conditions in the coronary care unit (CCU) compared to portable daily chest radiography (CXR) and conventional transthoracic echocardiography (TTE). An experienced pocket ultrasound user performed a pocket ultrasound examination for interstitial edema, pneumonia, central line seen in the right ventricle, pleural and pericardial effusions, left atrial enlargement, and cardiomegaly. Data were blindly compared to the radiologist CXR interpretation and cardiologist TTE interpretation. A total of 102 CXR and pocket ultrasound examinations were performed in 66 patients. The most common CXR indication was "interval change" (37%) and finding central line (65%). Pocket ultrasound demonstrated overall good concordance with CXR ranging from 77% for pleural effusion to 92% for pneumonia. Additionally, the pocket ultrasound examination appeared to anticipate resolution of pulmonary edema prior to the CXR. Compared to TTE, pocket ultrasound had excellent sensitivity for cardiac findings with values ranging from 85% for left atrial enlargement to 100% for cardiomegaly, but limited specificity of cardiomegaly at just 51%. In the CCU, bedside pocket ultrasound reliably diagnoses common conditions identified by CXR with the advantage of lack of ionizing radiation and the suggestion of detecting the resolution of pulmonary edema prior to CXR. Pitfalls include only modest concordance for pleural effusions and limited specificity for cardiomegaly. Larger, multicenter studies are needed to determine whether pocket ultrasound can reduce routine daily CXR in the CCU and other intensive care settings. © 2017, Wiley Periodicals, Inc.

  12. Utility of Chest Radiography in Emergency Department Patients Presenting with Syncope

    Directory of Open Access Journals (Sweden)

    Matthew L Wong

    2016-11-01

    Full Text Available Introduction Syncope has myriad etiologies, ranging from benign to immediately life threatening. This frequently leads to over testing. Chest radiographs (CXR are among these commonly performed tests despite their uncertain diagnostic yield. The objective is to study the distribution of normal and abnormal chest radiographs in patients presenting with syncope, stratified by those who did or did not have an adverse event at 30 days. Methods We performed a post-hoc analysis of a prospective cohort of consecutive patients presenting to an urban tertiary care academic medical center with a chief complaint of syncope from 2003–2006. The frequency and findings for each CXR were reviewed, as well as emergency department and hospital discharge diagnoses, and 30-day outcome. Results There were 575 total subjects, 39.7% were male, and the mean age was 57.2 (SD 24.6. Of the 575 subjects, 403 (70.1% had CXRs performed, and 116 (20.2% had an adverse event after their syncope. Of the 116 people who had an adverse event, 15 (12.9% had a positive CXR, 81 (69.8% had a normal CXR, and 20 (17.2% did not have a CXR as part of the initial evaluation. Among the 459 people who did not have an adverse event, 3 (0.7% had a positive CXR, 304 (66.2% had a normal CXR, and 152 (33.1% did not have a CXR performed. Fifteen of the 18 patients (83.4% with an abnormal CXR had an adverse event. Eighty-one of the 385 patients (21.0% with a normal CXR had an adverse event. Among those who had a CXR performed, an abnormal CXR was associated with increased odds of adverse event (OR: 18.77 (95% CI= [5.3–66.4]. Conclusion Syncope patients with abnormal CXRs are likely to experience an adverse event, though the majority of CXRs performed in the work up of syncope are normal.

  13. Basic ultrasound training can replace chest radiography for safe tube thoracostomy removal.

    Science.gov (United States)

    Lavingia, Kedar S; Soult, Michael C; Collins, Jay N; Novosel, Timothy J; Weireter, Leonard J; Britt, L D

    2014-08-01

    An ultrasound (US) examination can be easily and rapidly performed at the bedside to aide in clinical decisions. Previously we demonstrated that US was safe and as effective as a chest x-ray (CXR) for removal of tube thoracostomy (TT) when performed by experienced sonographers. This study sought to examine if US was as safe and accurate for the evaluation of pneumothorax (PTX) associated with TT removal after basic US training. Patients included had TT managed by the surgical team between October 2012 and May 2013. Bedside US was performed by a variety of members of the trauma team before and after removal. All residents received, at minimum, a 1-hour formal training class in the use of ultrasound. Data were collected from the electronic medical records. We evaluated 61 TTs in 61 patients during the study period. Exclusion of 12 tubes occurred secondary to having incomplete imaging, charting, or death before having TT removed. Of the 49 remaining TT, all were managed with US imaging. Average age of the patients was 40 years and 30 (61%) were male. TT was placed for PTX in 37 (76%), hemothorax in seven (14%), hemopneumothorax in four (8%), or a pleural effusion in one (2%). Two post pull PTXs were correctly identified by residents using US. This was confirmed on CXR with appropriate changes made. US was able to successfully predict the safe TT removal and patient discharge at all residency levels after receiving a basic US training program.

  14. Detection of tuberculosis using digital chest radiography: automated reading vs. interpretation by clinical officers.

    Science.gov (United States)

    Maduskar, P; Muyoyeta, M; Ayles, H; Hogeweg, L; Peters-Bax, L; van Ginneken, B

    2013-12-01

    A busy urban health centre in Lusaka, Zambia. To compare the accuracy of automated reading (CAD4TB) with the interpretation of digital chest radiograph (CXR) by clinical officers for the detection of tuberculosis (TB). A retrospective analysis was performed on 161 subjects enrolled in a TB specimen bank study. CXRs were analysed using CAD4TB, which computed an image abnormality score (0-100). Four clinical officers scored the CXRs for abnormalities consistent with TB. We compared the automated readings and the readings by clinical officers against the bacteriological and radiological results used as reference. We report here the area under the receiver operating characteristic curve (AUC) and kappa (κ) statistics. Of 161 enrolled subjects, 97 had bacteriologically confirmed TB and 120 had abnormal CXR. The AUCs for CAD4TB and the clinical officers were respectively 0.73 and 0.65-0.75 in comparison with the bacteriological reference, and 0.91 and 0.89-0.94 in comparison with the radiological reference. P values indicated no significant differences, except for one clinical officer who performed significantly worse than CAD4TB (P < 0.05) using the bacteriological reference. κ values for CAD4TB and clinical officers with radiological reference were respectively 0.61 and 0.49-0.67. CXR assessment using CAD4TB and by clinical officers is comparable. CAD4TB has potential as a point-of-care test and for the automated identification of subjects who require further examinations.

  15. Pulmonary infections in the late period after allogeneic bone marrow transplantation: chest radiography versus computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Schueller, Gerd [Department of Radiology, University Hospital Vienna, Waehringer Guertel 18-20/7F, A-1090 Vienna (Austria)]. E-mail: gerd.schueller@univie.ac.at; Matzek, Wolfgang [Department of Radiology, University Hospital Vienna, Waehringer Guertel 18-20/7F, A-1090 Vienna (Austria); Kalhs, Peter [Department of Internal Medicine I, University of Vienna Medical School (Austria); Schaefer-Prokop, Cornelia [Department of Radiology, University Hospital Vienna, Waehringer Guertel 18-20/7F, A-1090 Vienna (Austria)

    2005-03-01

    Purpose: To analyze the capabilities of chest roentgenogram (CXR) and computed tomography (CT) in the evaluation of pulmonary infectious disease in the late period (>100 days) after allogeneic bone marrow transplantation (BMT). Methods: Ninety-four matched CXR and CT examinations were performed for clinical suspicion of infectious lung disease. The time gap between CXR and CT was 48 h at maximum. The image pairs were correlated with the patients' clinical course and with the results of diagnostic bronchoalveolar lavage (BAL). An unremarkable clinical course over the subsequent seven days after imaging and/or negative microbiological culture served as the basis for excluding infectious lung disease. Positive microbiological culture and/or improvement of symptoms after antibiotic therapy were considered as evidence of infectious disease. Results: The correlation with the clinical course and/or BAL revealed a significantly higher sensitivity, negative predictive value, and accuracy for CT than for CXR (89% versus 58%, P < 0.0001; 78% versus 47%, P < 0.0001; 90% versus 68%, P < 0.0001, respectively). CT was significantly more diagnostic in BAL verified fungal and bacterial infections (P < 0.05). Conclusion: CT is significantly superior to CXR in the evaluation of infectious pulmonary disease in the late phase after BMT. Therefore, an unremarkable CXR should be followed by a CT scan to reliably detect or to accurately exclude early pulmonary infection in these patients.

  16. Sex determination based on a thoracic vertebra and ribs evaluation using clinical chest radiography.

    Science.gov (United States)

    Tsubaki, Shun; Morishita, Junji; Usumoto, Yosuke; Sakaguchi, Kyoko; Matsunobu, Yusuke; Kawazoe, Yusuke; Okumura, Miki; Ikeda, Noriaki

    2017-07-01

    Our aim was to investigate whether sex can be determined from a combination of geometric features obtained from the 10th thoracic vertebra, 6th rib, and 7th rib. Six hundred chest radiographs (300 males and 300 females) were randomly selected to include patients of six age groups (20s, 30s, 40s, 50s, 60s, and 70s). Each group included 100 images (50 males and 50 females). A total of 14 features, including 7 lengths, 5 indices for the vertebra, and 2 types of widths for ribs, were utilized and analyzed for sex determination. Dominant features contributing to sex determination were selected by stepwise discriminant analysis after checking the variance inflation factors for multicollinearity. The accuracy of sex determination using a combination of the vertebra and ribs was evaluated from the selected features by the stepwise discriminant analysis. The accuracies in each age group were also evaluated in this study. The accuracy of sex determination based on a combination of features of the vertebra and ribs was 88.8% (533/600). This performance was superior to that of the vertebra or ribs only. Moreover, sex determination of subjects in their 20s demonstrated the highest accuracy (96.0%, 96/100). The features selected in the stepwise discriminant analysis included some features in both the vertebra and ribs. These results indicate the usefulness of combined information obtained from the vertebra and ribs for sex determination. We conclude that a combination of geometric characteristics obtained from the vertebra and ribs could be useful for determining sex. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Evaluation of Image According to Exposure Conditions using Contrast-Detail Phantom for Chest Digital Radiography

    Energy Technology Data Exchange (ETDEWEB)

    Lee, In Ja [Dept. of Radiologic Tecnology, Dongnam Health College, Suwon (Korea, Republic of); Kim, You Hyun; Kim, Chang Nam [Dept. of Radiological Science, College of Health Science, Korea University, Seoul (Korea, Republic of); Kim, Chang Nam; Lee, Chang Yeob; Park, Kye Yeon [Dept. of Diagnostic Radiology, Korea University Guro Hospital, Seoul (Korea, Republic of)

    2009-03-15

    To find out proper photographing conditions in the chest DR imaging, the evaluation of images using the C-D phantom was carried out on relationship of identification capability, graininess, and exposure ratio. The conclusions were obtained as follows. 1. The patient's entrance skin Exposure (ESE) was decreased as tube voltage was increased. 2. According to the tube voltage change, the C-D phantom's identification capability of the exposure conditions was most visible at 110 kVp. 3. The identification capability according to the exposure ratio (mAs) change was most visible at 90 kVp for 0.5 times of low exposure ratio and at 110 kVp for 1.5 times. Therefore, it is known that the images were able to be better identified at a high exposure than a low exposure. 4. The graininess according to the exposure ratio at tube voltage of 110 kVp resulted in the best thing at 1.5 times of ratio when the exposure ratio was 1.5 times increased and the tube voltage was changed, the graininess showed the best result at 110 kVp. Therefore, the patient's exposure dose was low when kVp was increased and the adequate kVp was found to be 110. The image was better identified when exposure ratio was 1.5 times compared to 1.0 times. The graininess was also good when the exposure ratio became 1.5 times. The tube voltage was good at 110 kVp. However, once the exposure ratio is increased, the amount of radiation dose that the patients received get increased, so that the exposure condition has to be thoroughly considered.

  18. Assessing the role of routine chest radiography in asymptomatic students during registration at a university in an endemic area of tuberculosis

    Directory of Open Access Journals (Sweden)

    Moifo Boniface

    2012-01-01

    Full Text Available Context: Routine chest radiographs are usually obtained from asymptomatic individuals during routine medical visits probably to detect the presence of occult disease. In sub-Saharan countries tuberculosis is endemic among young individuals; primary tuberculosis might be the most probable occult disease sought for. Aims: The aim was to determine the diagnostic yield and cost-effectiveness of routine chest radiography in an asymptomatic student population in Yaounde during registration at a university. Settings and Design: A cross-sectional descriptive study carried out in a University-affiliated hospital in Yaounde, Cameroon. Materials and Methods: Postero-anterior (PA chest radiographs were obtained from students during a routine medical visit before university admission. Radiographic results were coded as normal, minor, or major findings. The estimated cost per radiograph was that of the study setting at the time of the study. Statistical Analysis Used: Epi Info software version 3.3.2 of February 9 2005 (CDC Atlanta was used for statistical analysis. Results: Of 758 students enrolled, there were 280 males and 478 females (sex ratio 1:2. The mean age of the study population was 21 years (age range 15-33 years. All enrolled cases were asymptomatic. There were 739 normal radiographs (97.5%, while 19 radiographs (2.5 % showed minor abnormalities. No major abnormality was seen. The estimated direct cost of all the radiographs obtained was 3,941,600 F CFA ($ 8,760. Conclusions: Routine chest radiography has a low diagnostic yield in asymptomatic students even in a setting where tuberculosis is endemic, and is therefore not cost-effective.

  19. Comparative evaluation of chest radiography, low-field MRI, the Shwachman-Kulczycki score and pulmonary function tests in patients with cystic fibrosis

    Energy Technology Data Exchange (ETDEWEB)

    Anjorin, Angela; Vogl, Thomas J. [Johann Wolfgang Goethe University, Institute for Diagnostic and Interventional Radiology, Frankfurt am Main (Germany); Schmidt, Helga [Johann Wolfgang Goethe University, Department of Pediatric Radiology, Institute for Diagnostic and Interventional Radiology, Frankfurt am Main (Germany); Posselt, Hans-Georg [Johann Wolfgang Goethe University, Clinics for Pediatry, Gastroenterology, Frankfurt am Main (Germany); Smaczny, Christina [Johann Wolfgang Goethe University, Medical Clinics I, Pneumology, Frankfurt am Main (Germany); Ackermann, Hanns [Johann Wolfgang Goethe University, Department of Biomathematics, Frankfurt am Main (Germany); Deimling, Michael [Siemens Medical Solutions, Erlangen (Germany); Abolmaali, Nasreddin [Dresden University of Technology, OncoRay - Molecular Imaging, Medical Faculty Carl Gustav Carus, Dresden (Germany)

    2008-06-15

    The aim of this study was to investigate whether the parenchymal lung damage in patients suffering from cystic fibrosis (CF) can be equivalently quantified by the Chrispin-Norman (CN) scores determined with low-field magnetic resonance imaging (MRI) and conventional chest radiography (CXR). Both scores were correlated with pulmonary function tests (PFT) and the Shwachman-Kulczycki method (SKM). To evaluate the comparability of MRI and CXR for different states of the disease, all scores were applied to patients divided into three age groups. Seventy-three CF patients (mean SKM score: 62 {+-} 8) with a median age (range) of 14 years (7-32) were included. The mean CN scores determined with both imaging methods were comparable (CXR: 12.1 {+-} 4.7; MRI: 12.0 {+-} 4.5) and showed high correlation (P < 0.05, R = 0.97). Only weak correlations were found between imaging, PFT, and SKM. Both imaging modalities revealed significantly more severe disease expression with age, while PFT and SKM failed to detect early signs of disease. We conclude that imaging of the lung in CF patients is capable of detecting subtle and early parenchymal destruction before lung function or clinical scoring is affected. Furthermore, low-field MRI revealed high consistency with chest radiography and may be used for a thorough follow-up while avoiding radiation exposure. (orig.)

  20. Development of Portable Digital Radiography System with a Device for Monitoring X-ray Source-Detector Angle and Its Application in Chest Imaging

    Directory of Open Access Journals (Sweden)

    Tae-Hoon Kim

    2017-03-01

    Full Text Available This study developed a device measuring the X-ray source-detector angle (SDA and evaluated the imaging performance for diagnosing chest images. The SDA device consisted of Arduino, an accelerometer and gyro sensor, and a Bluetooth module. The SDA values were compared with the values of a digital angle meter. The performance of the portable digital radiography (PDR was evaluated using the signal-to-noise (SNR, contrast-to-noise ratio (CNR, spatial resolution, distortion and entrance surface dose (ESD. According to different angle degrees, five anatomical landmarks were assessed using a five-point scale. The mean SNR and CNR were 182.47 and 141.43. The spatial resolution and ESD were 3.17 lp/mm (157 μm and 0.266 mGy. The angle values of the SDA device were not significantly difference as compared to those of the digital angle meter. In chest imaging, the SNR and CNR values were not significantly different according to the different angle degrees. The visibility scores of the border of the heart, the fifth rib and the scapula showed significant differences according to different angles (p < 0.05, whereas the scores of the clavicle and first rib were not significant. It is noticeable that the increase in the SDA degree was consistent with the increases of the distortion and visibility score. The proposed PDR with a SDA device would be useful for application in the clinical radiography setting according to the standard radiography guidelines.

  1. Bedside chest radiography of novel influenza A (H7N9) virus infections and follow-up findings after short-time treatment

    Institute of Scientific and Technical Information of China (English)

    SONG Feng-xiang; ZHOU Jun; SHI Yu-xin; ZHANG Zhi-yong; FENG Feng; ZHOU Jian-jun; WANG Qing-le

    2013-01-01

    Background Influenza A (H7Ng) virus infections were first observed in China in March 2013.This type virus can cause severe illness and deaths,the situation raises many urgent questions and global public health concerns.Our purpose was to investigate bedside chest radiography findings for patients with novel influenza A (H7Ng) virus infections and the followup appearances after short-time treatment.Methods Eight hospitalized patients infected with the novel influenza A (H7Ng) virus were included in our study.All of the patients underwent bedside chest radiography after admission,and all had follow-up bedside chest radiography during their first ten days,using AXIOM Aristos MX and/or AMX-Ⅳ portable X-ray units.The exposure dose was generally 90 kV and 5 mAs,and was slightly adjusted according to the weight of the patients.The initial radiography data were evaluated for radiological patterns (ground glass opacity,consolidation,and reticulation),distribution type (focal,multifocal,and diffuse),lung zones involved,and appearance at follow-up while the patients underwent therapy.Results All patients presented with bilateral multiple lung involvement.Two patients had bilateral diffuse lesions,three patients had unilateral diffuse lesions of the right lobe with multifocal lesions of the left lobe,and the remaining three had bilateral multifocal lung lesions.The lesions were present throughout bilateral lung zones in three patients,the whole right lung zone in three patients with additional involvement in the left middle and/or lower lung zone(s),both lower and middle lung zones in one patient,and the right middle and lower in combination with the left lower lung zones in one patient.The most common abnormal radiographic patterns were ground glass opacity (8/8),and consolidation (8/8).In three cases examined by CT we also found the pattern of reticulation in combination with CT images.Four patients had bilateral and four had unilateral pleural effusion.After a short

  2. Use and imaging performance of CMOS flat panel imager with LiF/ZnS(Ag) and Gadox scintillation screens for neutron radiography

    Science.gov (United States)

    Cha, B. K.; kim, J. Y.; Kim, T. J.; Sim, C.; Cho, G.; Lee, D. H.; Seo, C.-W.; Jeon, S.; Huh, Y.

    2011-01-01

    In digital neutron radiography system, a thermal neutron imaging detector based on neutron-sensitive scintillating screens with CMOS(complementary metal oxide semiconductor) flat panel imager is introduced for non-destructive testing (NDT) application. Recently, large area CMOS APS (active-pixel sensor) in conjunction with scintillation films has been widely used in many digital X-ray imaging applications. Instead of typical imaging detectors such as image plates, cooled-CCD cameras and amorphous silicon flat panel detectors in combination with scintillation screens, we tried to apply a scintillator-based CMOS APS to neutron imaging detection systems for high resolution neutron radiography. In this work, two major Gd2O2S:Tb and 6LiF/ZnS:Ag scintillation screens with various thickness were fabricated by a screen printing method. These neutron converter screens consist of a dispersion of Gd2O2S:Tb and 6LiF/ZnS:Ag scintillating particles in acrylic binder. These scintillating screens coupled-CMOS flat panel imager with 25x50mm2 active area and 48μm pixel pitch was used for neutron radiography. Thermal neutron flux with 6x106n/cm2/s was utilized at the NRF facility of HANARO in KAERI. The neutron imaging characterization of the used detector was investigated in terms of relative light output, linearity and spatial resolution in detail. The experimental results of scintillating screen-based CMOS flat panel detectors demonstrate possibility of high sensitive and high spatial resolution imaging in neutron radiography system.

  3. Follow-up chest radiography in surgical breast cancer patients; La radiografia del torace nel controllo delle pazienti operate per neoplasia della mammella

    Energy Technology Data Exchange (ETDEWEB)

    Coppola, V.; Brunese, L.; Gatta, G. [Neapel Univ., Neapel (Italy). Ist. di Scienze Radiologiche; Coppola, M.; Alfano, L. [Azienda Sanitaria Locale, Salerno (Italy). Unita' Operativa di Chirurgia; Cariello, S. [Azienda Sanitaria Locale, Salerno (Italy). Unita' Operativa di Oncologia Medica; Maioli, A. [Azienda Sanitaria Locale, Salerno (Italy). Unita' Operativa di Radiologia

    1999-10-01

    In this report is investigated to what extent the diagnostic findings of chest radiography can improve prognosis and treatment in surgical breast cancer patients. It is also reviewed the literature and the personal findings to choose the optima follow-up frequency to meet therapeutical and management needs, including radiation protection. [Italian] Scopo dello studio e' verificare l'utilita' e l'efficacia diagnostica della radiografia del torace ai fini del miglioramento prognostico e terapeutico delle pazienti operate per neoplasia mammaria proponendo, anche sulla base dei dati della letteratura, la cadenza di controllo preferibile che consenta di contemperare le esigenze terapeutiche e gestionali, ivi compresi gli obblighi radioprotezionistici.

  4. Comparison of two kind of flat panel detector radiography system: imaging quality versus exposure dose%两种平板探测器X线摄影系统的成像剂量与成像质量的比较研究

    Institute of Scientific and Technical Information of China (English)

    王鹏程; 张富利; 李士骏

    2006-01-01

    目的 定量分析、比较非晶硅平板探测器X射线摄影系统与非晶硒平板探测器X射线摄影系统在不同成像剂量条件下成像质量的差别.方法 以非晶硅平板探测器系统和非晶硒平板探测器系统分别摄取对比度-细节体模CDRAD2.0在相近曝光剂量条件下的X射线影像,由4位独立观察者分别阅读影像,并计算所对应的曝光剂量下图像质量因子(image quality figure,IQF),应用ANOVA分析两成像系统对比度及细节检测能力.使用X射线摄影统计学体模(TRG)测量两系统在不同曝光剂量条件下操作者特性曲线(receive operating characteristics,ROC),应用Wilcoxon检验分析、比较两种成像技术的影像信息检测能力的差别.结果 在低曝光剂量条件下,两系统CDRAD体模影像IQF值及ROC曲线AZ值差别有显著意义,在对比度、组织细节检测能力上非晶硅平板探测器系统优于非晶硒平板探测器系统.在高曝光剂量条件下,两系统差异无统计学意义.结论 在低曝光剂量条件下,成像质量非晶硅平板探测器系统优于非晶硒系统.在获得相同的影像质量的前提下,使用前者进行X射线摄影可以降低被检者受照剂量.

  5. 数字X线摄影焦点至探测器距离与体表入射剂量及影像质量的相关性%Correlation of focus-to-flat panel detector distance to radiation dosage and image quality in digital radiography

    Institute of Scientific and Technical Information of China (English)

    陈晓飞; 周晟; 曹红霞; 李清花; 汪新柱; 王闻奇

    2016-01-01

    目的 探讨数字化X线摄影(DR)焦点至探测器距离(FFD)与辐射剂量和影像质量的相关性.方法 去除滤线栅,采用自动曝光(AEC)模式对聚甲基丙烯酸甲酯和细节低对比度分析体模(CDRAD 2.0)进行DR摄影,管电压分别为70 kV、90 kV;通过手动调节,设定1 6个不同的FFD,在100~250 cm范围内以10 cm递增.记录曝光指数(EI),采用X线剂量仪测量体表入射剂量(ESD)和管电流,计算影像质量因子倒数(IQFinv),并进行统计学分析.结果 管电压70kV时,FFD与管电流呈高度正相关(r1=o.993,P<0.05);FFD与EI呈中度正相关(r2=0.649,P<0.05);FFD与ESD呈高度负相关(r3=0.935,P<0.05);FFD与IQFimv呈中度度负相关(r4=-0.699,P<0.05).管电压90 kV时,FFD与管电流呈高度正相关(r5=0.985,P<0.05);FFD与EI无相关性(r6=-0.206,P>0.05);FFD与ESD呈高度负相关(r7=-0.968,P<0.05);FFD与IQFinv呈中度负相关(r8=-0.628,P<0.05).r1与r5、r3与r7、r4与r8差异均无统计学意义(P均>0.05).结论 AEC模式下DR摄影,随着FFD自100~250 cm范围内增加,可降低辐射剂量,但影像细节低对比度会略有降低,在实际应用中应根据诊断要求进行FFD参数的优化.

  6. Pulmonary ultrasound and pulse oximetry versus chest radiography and arterial blood gas analysis for the diagnosis of acute respiratory distress syndrome: a pilot study.

    Science.gov (United States)

    Bass, Cameron M; Sajed, Dana R; Adedipe, Adeyinka A; West, T Eoin

    2015-07-21

    In low-resource settings it is not always possible to acquire the information required to diagnose acute respiratory distress syndrome (ARDS). Ultrasound and pulse oximetry, however, may be available in these settings. This study was designed to test whether pulmonary ultrasound and pulse oximetry could be used in place of traditional radiographic and oxygenation evaluation for ARDS. This study was a prospective, single-center study in the ICU of Harborview Medical Center, a referral hospital in Seattle, Washington, USA. Bedside pulmonary ultrasound was performed on ICU patients receiving invasive mechanical ventilation. Pulse oximetric oxygen saturation (SpO2), partial pressure of oxygen (PaO2), fraction of inspired oxygen (FiO2), provider diagnoses, and chest radiograph closest to time of ultrasound were recorded or interpreted. One hundred and twenty three ultrasound assessments were performed on 77 consecutively enrolled patients with respiratory failure. Oxygenation and radiographic criteria for ARDS were met in 35 assessments. Where SpO2 ≤ 97%, the Spearman rank correlation coefficient between SpO2/FiO2 and PaO2/FiO2 was 0.83, p arterial blood gas testing and chest radiography are not readily available.

  7. 精神疾病患者CR胸部CR质量控制方案%Quality Control Program in CR Chest Radiography of Mental Illness Patients

    Institute of Scientific and Technical Information of China (English)

    许光凯; 陈永红; 王斌

    2011-01-01

    Objective To explore CR chest photography of mental illness patients and master the CR technology, and to evaluate the response program function for chest radiographic image quality of menial disorders. Methods 1000 cases of CR chest images of inpatients in brain department in 2009 were collected and evaluated by the four radiologists with more than 5 years of work experience, Results In 1000 cases of mental disorders patients with chest radiography image, class A was 923 leaves, A rate was 92.3%, class B was 62 leaves, B rate was 6.2%, class waste was 15 leaves, and the rale was 1.5%. Coclusion By quality control of CR, characteristics of various types of mental illness condition are identified, and the response program can improve the chest radiographic image quality effectively.%目的:探索精神疾病患者CR胸部CR技术,掌握CR技巧,评价应对方案对精神疾病患者胸部影像图像质量的作用.方法:收集整理某医院2009年度1000例脑科住院患者CR胸片图像,由4位具有5年以上工作经验放射科医师分组进行读片评析.结果:1 000例精神疾病患者胸部CR图像中,甲级片923张,甲级片率92.3%;乙级片62张,乙级片率6.2%;废片巧张,废片率1.5%.结论:通过CR质量控制,明确各类精神疾病患者病情特点,制定的应对方案能有效提高胸部CR影像质量,值得借鉴.

  8. Accuracy of Lung Ultrasonography versus Chest Radiography for the Diagnosis of Adult Community-Acquired Pneumonia: Review of the Literature and Meta-Analysis.

    Directory of Open Access Journals (Sweden)

    Xiong Ye

    Full Text Available Lung ultrasonography (LUS is being increasingly utilized in emergency and critical settings. We performed a systematic review of the current literature to compare the accuracy of LUS and chest radiography (CR for the diagnosis of adult community-acquired pneumonia (CAP. We searched in Pub Med, EMBASE dealing with both LUS and CR for diagnosis of adult CAP, and conducted a meta-analysis to evaluate the diagnostic accuracy of LUS in comparison with CR. The diagnostic standard that the index test compared was the hospital discharge diagnosis or the result of chest computed tomography scan as a "gold standard". We calculated pooled sensitivity and specificity using the Mantel-Haenszel method and pooled diagnostic odds ratio using the DerSimonian-Laird method. Five articles met our inclusion criteria and were included in the final analysis. Using hospital discharge diagnosis as reference, LUS had a pooled sensitivity of 0.95 (0.93-0.97 and a specificity of 0.90 (0.86 to 0.94, CR had a pooled sensitivity of 0.77 (0.73 to 0.80 and a specificity of 0.91 (0.87 to 0.94. LUS and CR compared with computed tomography scan in 138 patients in total, the Z statistic of the two summary receiver operating characteristic was 3.093 (P = 0.002, the areas under the curve for LUS and CR were 0.901 and 0.590, respectively. Our study indicates that LUS can help to diagnosis adult CAP by clinicians and the accuracy was better compared with CR using chest computed tomography scan as the gold standard.

  9. Three-dimensional reconstructed magnetic resonance imaging for diagnosing persistent left superior vena cava. Comparison with magnetic resonance angiography and plain chest radiography

    Energy Technology Data Exchange (ETDEWEB)

    Koito, Hitoshi; Suzuki, Junichi; Ohkubo, Naohiko; Ishiguro, Yuka; Iwasaka, Toshiji; Inada, Mitsuo; Nakano, Yoshihisa [Kansai Medical Univ., Moriguchi, Osaka (Japan)

    1996-09-01

    The usefulness of low-cost, three-dimensional (3D) images reconstructed from magnetic resonance (MR) imaging for investigating persistent left superior vena cava was assessed and compared to the diagnostic accuracy of chest radiography. MR imaging by the spin-echo technique and MR angiography were performed in 10 patients with this anomaly diagnosed previously by contrast echocardiography and radionuclide angiocardiography. Four patients had complicating cardiac anomalies, one with postoperative atrial septal defect, one with postoperative ventricular septal defect, one with atrial septal defect and partial anomalous pulmonary venous return, and one with aortic coarctation and patent ductus arteriosus. Multisectional and multiphasic MR images were used for the 3D-reconstruction of the cardiovascular and mediastinal structures with a NeXT workstation and a 3D-kit. The 3D-reconstructed MR imaging clearly showed the persistent left superior vena cava and the anatomical relationship with the other cardiovascular and mediastinal structures in all 10 patients. Vascular shadows were observed outside the upper left border of the aortic arch on the chest radiographs in seven patients, and the 3D-reconstructed MR images revealed these shadows to be compatible with superior caval vein. The ratios of the diameter between the left and right superior venae cavae with and without the left innominate vein were 0.63{+-}0.14 (mean{+-}SD) and 0.94{+-}0.08, respectively. Three-dimensional reconstructed MR imaging is a useful method for recognizing persistent left superior vena cava and precise examination of the chest radiographs often allowed detection of the vascular shadows caused by this anomaly. (author)

  10. Lung Cancer Risk Following Detection of Pulmonary Scarring by Chest Radiography in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial

    Science.gov (United States)

    Yu, Ying-Ying; Pinsky, Paul F.; Caporaso, Neil E.; Chatterjee, Nilanjan; Baumgarten, Mona; Langenberg, Patricia; Furuno, Jon P.; Lan, Qing; Engels, Eric A.

    2010-01-01

    Background Fibrotic scars are frequently found in proximity to lung cancer at the time of cancer diagnosis. However, the nature of the relationship between pulmonary scarring and lung cancer remains uncertain. Our objective was to test whether localized pulmonary scarring is associated with increased lung cancer risk. Methods Cohort analysis of data from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. We included 66 863 cancer-free trial participants aged 55 to 74 years, who received a baseline chest radiographic examination and were followed up subsequently for up to 12 years. We used proportional hazards models to estimate hazard ratios (HRs) for lung cancer associated with scarring, adjusting for age, sex, race, and cigarette smoking, and in relation to laterality of scarring. The main outcome measure was incident lung cancer. Results Scarring was present on the baseline chest radiograph for 5041 subjects (7.5%). Scarring was associated with elevated lung cancer risk (809 lung cancer cases [HR, 1.5; 95% confidence interval {CI}, 1.2-1.8]). This association was specific for cancer in the lung ipsilateral to the scar (HR, 1.8; 95% CI, 1.4-2.4) and absent for contralateral cancer (HR, 0.9; 95% CI, 0.7-1.2). Ipsilateral lung cancer risk was elevated throughout the follow-up period (interval-specific HRs, 1.6, 2.0, 2.1, and 1.7 during 0.01-2.00, 2.01-4.00, 4.01-6.00, and 6.01-12.00 years after baseline chest radiography, respectively). Conclusions The relationship between pulmonary scarring and lung cancer was specific to the same lung and extended over time. These findings are consistent with the hypothesis that localized inflammatory processes associated with scarring promote the subsequent development of lung cancer. PMID:19029496

  11. High-resolution computed tomography versus chest radiography in the diagnosis of interstitial lung disease in systemic sclerosis; Avaliacao da tomografia de alta resolucao versus radiografia de torax na doenca intersticial pulmonar na esclerose sistemica

    Energy Technology Data Exchange (ETDEWEB)

    Azevedo, Ana Beatriz Cordeiro de; Calderaro, Debora; Moreira, Caio [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Hospital das Clinicas. Servico de Reumatologia; Guimaraes, Silvana Mangeon Meirelles [Gerais Univ., Belo Horizonte, MG (Brazil). Hospital das Clinicas. Secao de Tomografia Computadorizada; Tavares Junior, Wilson Campos; Leao Filho, Hilton Muniz; Andrade, Diego Correa de [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Hospital das Clinicas. Servico de Radiologia e Diagnostico por Imagem]. E-mail: wilsontavaresjrmd@yahho.fr; Ferreira, Cid Sergio; Vieira, Jose Nelson Mendes [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Faculdade de Medicina. Dept. de Radiologia

    2005-04-01

    Objective: To compare the accuracy of high-resolution computed tomography (HRCT) with chest radiography in the diagnosis of interstitial lung disease in systemic sclerosis (SSc). Materials And Methods: HRCT scans and chest radiographs in postero-anterior and lateral views were performed in 34 patients with systemic sclerosis, according to the American College of Rheumatology preliminary criteria for the diagnosis of SSc. The prevalence of radiological findings suggestive of interstitial lung disease in SSc seen on both imaging methods was compared. Results: Interstitial disease was observed on HRCT images of 31 patients (91%) and in the chest radiographs of 16 patients (47%). The most frequent findings observed on HRCT were septal lines (74%), honeycombing (56%) and parenchymal bands (26%). Chest radiographs showed reticular areas of attenuation in 11 patients (32%) and parenchymal distortion in 12% of the patients. In 18 patients (53%) with normal chest radiographs HRCT showed septal lines in 55%, ground glass in 44%, honeycombing in 38.5% and cysts in 33%. Conclusion: HRCT is more sensitive than chest radiography in the evaluation of incipient interstitial lung involvement in patients with SSc and can provide a justification for immunosuppressive therapy in patients with early disease. (author)

  12. Ventilation-perfusion-chest radiography match is less likely to represent pulmonary embolism if perfusion is decreased rather than absent.

    Science.gov (United States)

    Kim, C K; Worsley, D F; Alavi, A

    2000-09-01

    The authors' goal was to determine whether the prevalence of pulmonary embolism in patients with matching ventilation-perfusion (V-Q) defects and chest radiographic opacities differs depending on the degree of perfusion deficit (absent versus decreased). The authors performed a retrospective analysis of the data obtained from the Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) study. In 233 patients, angiograms were of diagnostic quality for 275 lung zones that showed matching V-Q defects and chest radiographic opacities (triple matches). Of these, V-Q scans and chest radiographs from 217 patients with triple matches in 255 lung zones were retrieved and reviewed. Areas corresponding to chest radiographic opacities were scored as having either decreased perfusion or absent perfusion by consensus. Information regarding the presence or absence of pulmonary embolism in corresponding lung zones was obtained from the PIOPED database. The overall prevalence of pulmonary embolism in all lung zones with triple matches was 27% (69 of 255). Of the 255 areas of triple matches, the perfusion was decreased in 153 (60%) and absent in 102 (40%). The prevalence of pulmonary embolism in areas of triple matches with decreased perfusion and triple matches with absent perfusion was 13% (20 of 153) and 48% (49 of 102), respectively (P = 0.0001 by the chi-square test). When these were divided further by lung zones, triple matches with decreased perfusion and triple matches with absent perfusion in the upper-middle lung zone were associated with a prevalence of 0% (O of 44), and 25% (9 of 36), respectively. The prevalence of pulmonary embolism in areas of triple matches with decreased perfusion and triple matches with absent perfusion in the lower lung zone was 18% (20 of 109), and 61% (40 of 66), respectively. A V-Q/chest radiographic match is less likely to represent pulmonary embolism if perfusion is decreased rather than absent. The overall prevalence of pulmonary

  13. To Screen or not to Screen: Low Dose Computed Tomography in Comparison to Chest Radiography or Usual Care in Reducing Morbidity and Mortality from Lung Cancer

    Science.gov (United States)

    Kamdar, Jay; Moats, Austin; Nguyen, Brenda

    2016-01-01

    Lung cancer has the highest mortality rate of all cancers. This paper seeks to address the question: Can the mortality of lung cancer be decreased by screening with low-dose computerized tomography (LDCT) in higher risk patients compared to chest X-rays (CXR) or regular patient care? Currently, CXR screening is recommended for certain high-risk patients. Several recent trials have examined the effectiveness of LDCT versus chest radiography or usual care as a control. These trials include National Lung Screening Trial (NLST), Detection And screening of early lung cancer with Novel imaging TEchnology (DANTE), Lung Screening Study (LSS), Depiscan, Italian Lung (ITALUNG), and Dutch-Belgian Randomized Lung Cancer Screening Trial (Dutch acronym: NELSON study). NLST, the largest trial (n=53, 454), demonstrated a decrease in mortality from lung cancer in the LDCT group (RRR=20%, P=0.004). LSS demonstrated a greater sensitivity in detecting both early stage and any stage of lung cancer in comparison to traditional CXR. Although the DANTE trial yielded data consistent with findings in LSS, it also showed that via LDCT screening a greater proportion of patients were placed under unnecessary surgical procedures. The Depiscan trial yielded a high nodule detection rate at the cost of a high false-positive rate compared to CXR screening. The ITALUNG and NELSON trials demonstrated the early detection capabilities of LDCT for lung cancers compared to usual care without surveillance imaging. False-positive findings with unnecessary workup, intervention, and radiation exposure remain significant concerns for routine LDCT screening. However, current data suggests LDCT may provide a highly sensitive and specific means for detecting lung cancers and reducing mortality. PMID:27375974

  14. 新生儿床旁X线胸片的临床应用%Clinical application of bedside chest radiography in neonates

    Institute of Scientific and Technical Information of China (English)

    田治海; 高超; 焦振华; 王联营; 张力维; 师勇

    2012-01-01

    目的 评价新生儿床头X线胸片的临床应用价值.方法回顾分析137例共224份新生儿床旁胸片及临床资料,观察其心肺疾病X线表现.结果 224份床旁胸片中212份符合诊断要求,占 94.6 %.其中209份显示有心肺疾病:新生儿感染性肺炎 21例,新生儿湿肺12例,胎粪吸入性肺炎(MAS) 37例,新生儿肺透明膜病(NRDS)23例,急性呼吸窘迫综合征(ARDS)11例,新生儿肺出血4例,新生儿气胸28例,急性肺水肿7例,肺不张4例,先天性心脏病6例及先天性肺发育不良 1 例.单发病例48例,占35%,伴有合并症89例,占65%.其中MAS、NRDS、ARDS、先天性心脏病的合并症多见,共69例,占78%.结合临床资料,床旁胸片对肺炎、湿肺、NRDSⅠ~Ⅱ型、ARDS、MAS、肺不张、肺水肿、中到大量气胸及胸腔积液的初诊的准确率达80%.误诊、漏诊共7例,占5%.肺水肿与ARDS及ARDS与MAS合并NRDS的鉴别存在一定困难,需要结合临床随访复查.结论 床旁胸片能满足新生儿危重病的检查需要.%Objective To evaluate the clinical application of neonatal bedside chest radiography. Methods 224 bedside chest radiographs and clinical data in 137 nconatcs were retrospectively analysed. X-ray features of cardiopulmonary disease were observed. Results Of 224 bedside chest X-ray films, 212 were consistent with the diagnosis of requirements(94. 6%). 209 chest films showed heart or lung disease: including neonatal infectious pneumonia in 21 cases, wet lung of newborn in 12 cases, mcconium aspiration pneumonia (MAS) in 37 cases, neonatal pulmonary hyaline membrane disease ( NRDS ) in 23 patients, acute respiratory distress syndrome (ARDS ) in 11 cases, neonatal pulmonary hemorrhage in 4 cases, pneumothorax in 28 cases, acute pulmonary edema in 7 cases, pulmonary atclcctasis in 4 cases, congenital heart disease in 6 cases and congenital pulmonary hypoplasia in 1 case. The lesions single in 4 8 cascs(35 % ) , complicated in 89 cases(65 % ) . The

  15. 成人胸部适当高电压数字X线摄影试验研究%Optimisation of tube voltage for adult chest digital radiography

    Institute of Scientific and Technical Information of China (English)

    赵永霞; 秦维昌; 黄玲; 张晓晶; 亓恒涛; 刘传亚; 王巍

    2010-01-01

    Objective To explore the optimum voltage for digital chest radiography in adult. Methods PMMAs of Different thickness (7.2, 9.0, 10. 8 and 12. 6 cm) were used to simulate chest of different depth ( 17. 5, 22. 5, 27.0 and 32. 5 cm). The combinants of contrast-detail Cdrad 2.0 phantom and above PMMAs were exposed with automatic exposure control (AEC) and different tube voltages. The images of these combinants were obtained and the entrance surface dose (ESD) was recorded. The imaging quality factor (IQF) was calculated and the curves were drawn between the ESD,IQF and kV. The PMMAs of different thickness, on which a contrast object ( PMAA of 5 cm diameter and 1.8 cm thickness ) was placed, were exposed with the same condition used for above test. Their images were obtained and SNRs were calculated. Results The ESD, SNR and IQFinv of different chest depth decreased with increase of kV.When tube voltages of 70, 100 and 140 kV were used, for 17. 5 cm chest depth, the ESD was 0. 22, 0. 09 and 0. 06 mGy, the IQF was 43.3, 58. 8 and 72. 0, the SNR was 7.5, 6. 2 and 5.0; for 22. 5 cm chest depth, the ESD was 0.37, 0.12 and 0.06 mGy, the IQF was 56. 0, 61.4 and 65.3, the SNR was 6. 4, 5.2 and 3. 8; for 27. 0 cm chest depth, the ESD was 0. 52, 0. 20 and 0. 09 mGy, the IQF was 54. 2, 64. 3 and 91. 0, the SNR was 6. 0, 4. 8 and 3. 5; for 31.5 cm chest depth, the ESD was 0.53, 0.24 and 0. 10 mGy,the IQF was 53.2, 66. 8 and 95.3, the SNR was 5. 7, 4. 5 and 3. 0. Conclusion To balance ESD, SNR and IQF, proper tube voltage should be chosen for chest radiography according to thickness and constitution of patients.%目的 探讨成人胸部不同厚度高千伏DR的适当电压千伏值.方法 用不同厚度的聚甲基丙烯酸甲酯(PMMA)模拟不同成人胸部厚度,用不同电压、自动曝光控制(AEC)摄影,记录入射体表剂量(ESD)、获取模体影像并计算影像质量因子(IQF),绘制ESD和IQF之间的曲线.将一块厚度为1.8 cm(5 cm×5 cm)的PMMA作为对

  16. Efficacy of Increasing Focus to Film Distance (FFD for Patient’s Dose and Image Quality in Pediatric Chest Radiography

    Directory of Open Access Journals (Sweden)

    Vahid Karami

    2016-09-01

    Full Text Available Background: Increasing the x-ray focus to film distance (FFD has been advocated as an effective method to reduce the patients’ radiation dose. The aim of this study was to investigate the efficacy of this technique in patients' dose and image quality in pediatric chest x-ray.Material and methods: Sixty pediatric patients were x-ray imaged at FFDs of 100 and 130 cm. Dose measurements were performed using thermo-luminescent dosimeters (GR200. The quality of images was independently assessed using the anatomical criteria recommended by the European guidelines.Results: Increasing the FFD from 100 to 130 cm has reduced the entrance skin dose (ESD of patients by 32.2% (p 0.05.Conclusion: Increased FFD to 130 cm reduce the pediatric radiation dose with no significant changes in image quality.

  17. Development of profession and quality in radiography with focus on evaluation criteria and image quality of chest x-rays

    DEFF Research Database (Denmark)

    Debess, Jeanne; Thomsen, Henrik; Conradsen, Jacob

    2011-01-01

    Learning Objectives: Learning Objectives: To improve quality of chest xrays by Education Conferences for radiographers and evaluation of image quality. Background: Introduction of digital imaging technology and picture archiving and communication system (PACS) has changed the workflow in the x......-ray department including evaluation of image quality and feedback from radiologist to radiographer. Imaging Findings or Procedure Details: Procedure Details: Data for evaluation of image quality was collected by questionnaires aimed at: anatomy, image-focusing, image-collimation, exposure and body habitus...... collection were found. Evaluation results from anatomy, image-focusing, image-collimation and exposure from first data collection shows variations from 7 % to 37 % between evaluation at primary monitor by the radiographers and diagnostic monitor by the radiologist. In relation to anatomy, the quality...

  18. Effective DQE (eDQE) for monoscopic and stereoscopic chest radiography imaging systems with the incorporation of anatomical noise

    Energy Technology Data Exchange (ETDEWEB)

    Boyce, Sarah J. [Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 and Department of Biomedical Engineering, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27695 (United States); Choudhury, Kingshuk Roy [Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 (United States); Samei, Ehsan [Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 (United States); Carl E. Ravin Advanced Imaging Laboratories, Department of Biomedical Engineering, Duke University, Durham, North Carolina 27705 (United States); Carl E. Ravin Advanced Imaging Laboratories, Department of Physics, Duke University, Durham, North Carolina 27705 (United States)

    2013-09-15

    Purpose: Stereoscopic chest biplane correlation imaging (stereo/BCI) has been proposed as an alternative modality to single view chest x-ray (CXR). The metrics effective modulation transfer function (eMTF), effective normalized noise power spectrum (eNNPS), and effective detective quantum efficiency (eDQE) have been proposed as clinically relevant metrics for assessing clinical system performance taking into consideration the magnification and scatter effects. This study compared the metrics eMTF, eNNPS, eDQE, and detectability index for stereo/BCI and single view CXR under isodose conditions at two magnifications for two anthropomorphic phantoms of differing sizes.Methods: Measurements for the eMTF were taken for two phantom sizes with an opaque edge test device using established techniques. The eNNPS was measured at two isodose conditions for two phantoms using established techniques. The scatter was measured for two phantoms using an established beam stop method. All measurements were also taken at two different magnifications with two phantoms. A geometrical phantom was used for comparison with prior results for CXR although the results for an anatomy free phantom are not expected to vary for BCI.Results: Stereo/BCI resulted in improved metrics compared to single view CXR. Results indicated that magnification can potentially improve the detection performance primarily due to the air gap which reduced scatter by ∼20%. For both phantoms, at isodose, eDQE(0) for stereo/BCI was ∼100 times higher than that for CXR. Magnification at isodose improved eDQE(0) by ∼10 times for stereo/BCI. Increasing the dose did not improve eDQE. The detectability index for stereo/BCI was ∼100 times better than single view CXR for all conditions. The detectability index was also not improved with increased dose.Conclusions: The findings indicate that stereo/BCI with magnification may improve detectability of subtle lung nodules compared to single view CXR. Results were improved

  19. Computed Radiography and Computed Tomography of Chest Wall Diseases%胸壁病变的计算机X线摄影和CT检查

    Institute of Scientific and Technical Information of China (English)

    洪庆坚; 李惠民; 肖湘生; 王晨光; 胡爱妹

    2000-01-01

    Purpose: To analyze computed radiography (CR) and computed tomography (CT) findings of diseases of chest wall and to investigate the value of CR and CT in diagnosis of these diseases. Materials and Methods: The findings and diagnoses of 39 cases with proved (by fina needle biopsy, or surgory and/or pathology, of clinical follow up) chest wall disease were analysed retrospectively. Resulte: In 12 infective lesions, including purulent infection (4 cases) and tuberculosis (8 cases), the correct dignosis was made in 4cases by CR and in 11 cases by CT. In 16 soft tissue tumors, including lipoma (7 cases), fibrosarcoma (4 cases), hemangioma (1 case), neurofibroma (1 case), malignant fibrous histocytoma (1case), aggressive fibromatosis (1 case) and liposarcoma (1 case), the correct diagnosis was made in 3cases by CR and in 14 cases by CT. In 11 bone lesions, including fibrous dysplasia (7 cases), chondroma (2 cases), myeloma (lcase) and cosinophilic granuloma (1 case), the correct diagnosis was made in 8cases by CR and in 10 cases by CT. Conclusion: CR is useful in the dignosis of chest wall bone diseases. CT is obviously superior to CR for demonstration of all chest wall diseases espacially for soft tissue lesions. CT has definite value for the differentiation of malignant from benign tumore of chest wall, but still has certain limit.%目的:探讨胸壁病变的计算机X线摄影(CR)和CT表现及其诊断价值,提高对胸壁病变的认识。材料和方法:回顾分析经手术病理、穿刺细胞学检查或临床随访资料证实的39例CR和CT资料。结果:感染组12例中(包括化脓性感染4例,胸壁结核8例),CR准确诊断4例,CT诊断11例;软组织肿瘤组16例中(包括脂肪瘤7例,纤维肉瘤4例,血管瘤、神经纤维瘤、恶性纤维组织细胞瘤、侵袭性纤维瘤病和脂肪肉瘤各l例),CR准确诊断3例,CT诊断14例;骨肿瘤和肿瘤样病变组11例中(包括骨纤维异常增殖症7例,软骨瘤2

  20. Modified Chrispin-Norman chest radiography score for cystic fibrosis: observer agreement and correlation with lung function

    Energy Technology Data Exchange (ETDEWEB)

    Jong, P.A. de; Achterberg, J.A.; Kessels, O.A.M.; Beek, F.J. [Department of Radiology, University Medical Center Utrecht, Wilhelmina Children' s Hospital, Utrecht (Netherlands); Ginneken, B. van; Hogeweg, L. [Radboud University Nijmegen Medical Centre, Department of Radiology, Nijmegen (Netherlands); Image Sciences Institute, University Medical Center Utrecht, Utrecht (Netherlands); Terheggen-Lagro, S.W.J. [University Medical Center Utrecht, Wilhelmina Children' s Hospital, Department of Pediatric Pulmonology, Utrecht (Netherlands)

    2011-04-15

    To test observer agreement and two strategies for possible improvement (consensus meeting and reference images) for the modified Chrispin-Norman score for children with cystic fibrosis (CF). Before and after a consensus meeting and after developing reference images three observers scored sets of 25 chest radiographs from children with CF. Observer agreement was tested for line, ring, mottled and large soft shadows, for overinflation and for the composite modified Chrispin-Norman score. Correlation with lung function was assessed. Before the consensus meeting agreement between observers 1 and 2 was moderate-good, but with observer 3 agreement was poor-fair. Scores correlated significantly with spirometry for observers 1 and 2 (-0.72

  1. Comparison of chest radiography and high-resolution computed tomography findings in early and low-grade coal worker's pneumoconiosis.

    Science.gov (United States)

    Savranlar, Ahmet; Altin, Remzi; Mahmutyazicioğlu, Kamran; Ozdemir, Hüseyin; Kart, Levent; Ozer, Tülay; Gündoğdu, Sadi

    2004-08-01

    High-resolution computed tomography (HRCT) is more sensitive than chest X-ray (CXR) in the depiction of parenchymal abnormalities. We aimed to present and compare CXR and HRCT findings in coal workers with and without early and low-grade coal worker's pneumoconiosis (CWP). 71 coal workers were enrolled in this study. All workers were male. The CXR and HRCT of those workers were obtained and graded by two trained readers. HRCT's were graded according to Hosoda and Shida's Japanese classification. After grading, 67 workers with CXR profusion 0/0-2/2 were included in the study. Four patients with major opacity were excluded. Profusion 0/1 to 1/1 cases were accepted as early and profusion 1/2 and 2/2 cases as low-grade pneumoconiosis. Discordance between CXR and HRCT was high. Discordance rate was found higher in the early pneumoconiosis cases with negative CXR than low-grade pneumoconiosis (60, 36 and 8%, respectively). When coal miners with normal CXR were evaluated by HRCT, six out of 10 cases were diagnosed as positive. In low-grade pneumoconiosis group, the number of patients with positive CXR but negative HRCT were low in comparison to patients with CXR negative and early pneumoconiosis findings. Most of the CXR category 0 patients (10/16) were diagnosed as category 1 by HRCT. Eleven cases diagnosed as CXR category 1 were diagnosed as category 0 (7/11) and category 2 (4/11) by HRCT. In CXR category 2 (eight cases), there were four cases diagnosed as category 1 by HRCT. Discordance between CXR and HRCT was high, especially for CXR negative and early pneumoconiosis cases. The role of CXR in screening coal workers to detect early pneumoconiosis findings should be questioned. We suggest using HRCT as a standard screening method instead of CXR to distinguish between normal and early pneumoconiosis.

  2. Acurácia da radiografia de tórax associada a eletrocardiograma no diagnóstico de hipertrofia em hipertensos Accuracy of chest radiography plus electrocardiogram in diagnosis of hypertrophy in hypertension

    Directory of Open Access Journals (Sweden)

    Sergio Marrone Ribeiro

    2012-09-01

    Full Text Available FUNDAMENTO: A radiografia de tórax e o eletrocardiograma (ECG tem sido criticados em razão de sua baixa sensibilidade no diagnóstico da Hipertrofia Ventricular Esquerda (HVE quando comparada ao ecocardiograma. Entretanto, esse exame não está disponível nos centros de atendimento primário para toda a população de hipertensos. OBJETIVO: Avaliar se a radiografia de tórax associada ao eletrocardiograma apresenta acurácia que justifique seu uso na detecção de HVE em hipertensos, bem como a utilidade do índice cardiotorácico e das radiografias oblíquas na avaliação das dimensões das câmaras cardíacas esquerdas. MÉTODOS: Estudo prospectivo realizado em 177 pacientes hipertensos consecutivos, através da radiografia do tórax, eletrocardiograma e ecocardiograma. Testes de acurácia foram utilizados para comparar esses métodos utilizando a ecocardiografia convencional como padrão de referência. RESULTADOS: O índice cardiotorácico mostrou sensibilidade de 17% para o diagnóstico de HVE, somente detectando alterações cardíacas mais acentuadas. As incidências póstero-anterior e perfil tiveram sensibilidade de 52%, aumentando para 54% quando a radiografia de tórax foi associada ao eletrocardiograma. As incidências oblíquas não melhoraram significativamente a acurácia da radiografia de tórax que, por sua vez, apresentou alta especificidade e boa sensibilidade para a detecção do aumento da aorta. Foi interessante notar que essa alteração estava presente em metade dos hipertensos com HVE. CONCLUSÃO: A associação da radiografia de tórax com eletrocardiograma é útil na avaliação inicial de hipertensos para o diagnóstico de hipertrofia ventricular esquerda, especialmente se a ecocardiografia não estiver disponível. (Arq Bras Cardiol. 2012; [online].ahead print, PP.0-0BACKGROUND: Chest radiography and electrocardiogram have been criticized due to their low sensitivity for Left Ventricular Hypertrophy diagnosis

  3. Chest X-Ray (Chest Radiography)

    Science.gov (United States)

    ... clothing that might interfere with the x-ray images. Women should always inform their physician and x-ray ... small burst of radiation that passes through the body, recording an image on photographic film or a special detector. Different ...

  4. S100A12 is up-regulated in pulmonary tuberculosis and predicts the extent of alveolar infiltration on chest radiography: an observational study

    Science.gov (United States)

    Berrocal-Almanza, Luis C.; Goyal, Surabhi; Hussain, Abid; Klassert, Tilman E.; Driesch, Dominik; Grozdanovic, Zarko; Sumanlatha, Gadamm; Ahmed, Niyaz; Valluri, Vijayalakshmi; Conrad, Melanie L.; Dittrich, Nickel; Schumann, Ralf R.; Lala, Birgit; Slevogt, Hortense

    2016-01-01

    Pulmonary tuberculosis (PTB) results in lung functional impairment and there are no surrogate markers to monitor the extent of lung involvement. We investigated the clinical significance of S100A12 and soluble receptor for advanced glycation end-products (sRAGE) for predicting the extent of lung involvement. We performed an observational study in India with 119 newly diagnosed, treatment naïve, sputum smear positive, HIV-negative PTB patients and 163 healthy controls. All patients were followed-up for six months. Sociodemographic variables and the serum levels of S100A12, sRAGE, esRAGE, HMGB-1, TNF-α, IFN-γ and CRP were measured. Lung involvement in PTB patients was assessed by chest radiography. Compared with healthy controls, PTB patients had increased serum concentrations of S100A12 while sRAGE was decreased. S100A12 was an independent predictor of disease occurrence (OR 1.873, 95%CI 1.212–2.891, p = 0.004). Under DOTS therapy, S100A12 decreased significantly after 4 months whereas CRP significantly decreased after 2 months (p < 0.0001). Importantly, although CRP was also an independent predictor of disease occurrence, only S100A12 was a significant predictor of lung alveolar infiltration (OR 2.60, 95%CI 1.35–5.00, p = 0.004). These results suggest that S100A12 has the potential to assess the extent of alveolar infiltration in PTB. PMID:27539060

  5. The research of optimizing exposure factors in digital chest radiography%数字X线胸部摄影适宜检查参数的研究

    Institute of Scientific and Technical Information of China (English)

    孙建忠; 王志康; 章伟敏; 蔡劲松

    2010-01-01

    目的 探讨DR胸部摄影的适宜检查参数.方法 选择73、90、125 kV分别代表低、亚高、高kV,分别选择感度200、400、800以及各级感度±4微调,使用自动曝光控制(AEC)模式对内嵌有CDRAD 2.0的胸部体模曝光,记录每次曝光的剂量面积值(DAP).应用CDRAD 2.0配套分析软件Artinis CDRAD Analyzer 1.1自动分析每次曝光的图像质量(IQFinv)值.选择10名志愿者进行73 kV,S800-2;90 kV,S800+2;125 kV,S400+2,3种组合曝光,由2名医师进行评分,记录其DAP值,所得数据应用SPSS12.0软件进行单因素方差分析.结果 (1)3种组合志愿者曝光图像质量评分73、90、125 kV分别为(2.7±0.5)、(2.9±0.3)、(2.8±0.4)分,差异无统计学意义(F=0.587,P>0.05).73、90、125 kV的DAP分别为(29.1±7.9)、(30.5±4.5)、(40.4±7.6)mGy·cm2,差异有统计学意义(F=9.803,P<0.01).(2)3种kV体模曝光DAP值随着感度的增高而下降.每级感度间,DAP值相差11%;相同感度等级,DAP值73 kV>90 kV>125 kV.(3)3种kV体模曝光IQFinv 值均随着感度的增高而下降,相同曝光剂量下,IQFinv值73 kV>90 kV>125 kV.结论 90 kV与感度S800+2~S800+4组合是DR胸部X线摄影较为适宜的检查参数.%Objective To explore the optimum exposure factors in digital chest radiography.Methods Chest phantom was exposed under auto exposure control model with 73, 90, 125kV and S200,400,800 plus or minor 4 micro-adjust for each sensitivity grade. Meanwhile dose area product (DAP) was recorded and the value of IQFinv was analyzed automatically by Artinis CDRAD Analyzer 1.1. Ten volunteers were exposed with 73 kV, S800 - 2; 90 kV, S800 + 2 and 125 kV, S400 + 2. Two radiologists evaluated and scored image quality. Statistical analysis was performed using one way ANOVA test by SPSS 12. 0. Results ( 1 ) The quality scores of volunteers' images obtained with three combinations of exposure factors were 2. 7 ± 0. 5 for 73 kV group, 2. 9 ± 0. 3 for 90 kV group and 2. 8 ± 0. 4 for

  6. X射线胸部摄影曝光剂量与图像质量相关性研究%Study on correlation between exposure dose and image quality of X-ray chest radiography

    Institute of Scientific and Technical Information of China (English)

    曹允希; 蔡小涛; 谢晋东; 曹鑫

    2014-01-01

    Objective To investigate optimal radiation dose for digital radiography by researching the correlation between radiation dose and image quality of high kV chest radiography.Methods The kV of chest radiography was setted on 120 kV while mAs was changed.The chest radiography phantom and the contrast detail phantom CDRAD2.0 were exposed by DR with different mAs from 1 to 25 mAs.The entrance doses were measured for all exposures and the images were read independently by 5 observers on a higher resolution monitor of diagnosis work station.The image quality figure (IQF) was measured for each image.Comparison of the mean IQFs with different exposure doses were conducted in order to determined which was the optimal exposure condition for high kV radiography.The image quality of normal adult using different mAs,4 and 10 mAs for high KV chest radiography was compared.Results When the mAs was increased from 1 to 25 mAs,the entrance doses varied from 0.067 to 1.468 mGy.With the entrance doses increasing,the value of IQF was decreased (F =31.00,P < 0.05).The values of IQF were statistically different between 1 and 4 mAs(F =15.3,P <0.05),and between 10 and 25 mAs(F =9.74,P <0.05).At 4 and 10 mAs with the entrance dose 0.250 and 0.606 mGy,the synthesis score of chest high kV radiography from two kinds of exposure dose was (24.8 ± 1.64),(25.8 ± 2.05),with no statistically significant difference.Conclusions For digital radiography,increasing radiation dose can improve image information.The optimal entrance dose of high kV chest radiography for standard body was about 0.250 mGy.%目的 研究数字化X射线胸部高千伏摄影曝光剂量与图像质量的关系,确定数字化X射线摄影最佳曝光剂量.方法 选择胸部高千伏摄影管电压120 kV,摄影mAs从1 mAs逐档增加至25 mAs,对模拟人体胸部厚度摄影体模与CDRAD 2.0对比度细节体模进行摄影,测量体模表面X射线入射剂量,由5位观察者独立阅读体模影像,比较任意两

  7. [Physical image properties of digital radiography systems in low dose range].

    Science.gov (United States)

    Kunitomo, Hiroshi; Ichikawa, Katsuhiro; Higashide, Ryo; Ohashi, Kazuya

    2012-01-01

    We measured physical image properties of a flat panel detector (FPD) system and a computed radiography (CR) system, targeting to a low dose range (reference dose: 2.58×10(-7) C/kg: to 1/20 dose). Input-output properties, pre-sampled modulation transfer functions (pre-sampled MTFs), and normalized noise power spectra for an FPD system equipped with a CsI scintillator (FPDcsi) and a CR system with an imaging plate coated with storage phosphor (CR) were measured at the low dose range for radiation quality of RQA3 (≍50 skV) and RQA5 (≍70 kV), and detective quantum efficiencies (DQEs) were calculated. In addition, in order to validate the DQE results, component fractions of Poisson and multiplicative and additive noise were analyzed using relative standard deviation analysis. The DQE values of FPDcsi were decreased with dose decrease, and contrarily to these, those of CR were increased. At the 1/10 and 1/20 doses for RQA3, the DQEs of FPDcsi and CR became almost the same. From the results of RSD analysis, it was proved that the main cause of DQE deterioration on FPDcsi are non-negligible additive (electronic) noise, and the DQE improvement on CR was caused by both of significant multiplicative (structure) noise and very low electronic noise. The DQE results were validated by comparing burger phantom images of each dose and radiation quality.

  8. Optimizing the tube potential for lumbar spine radiography with a flat-panel digital detector.

    Science.gov (United States)

    Geijer, H; Norrman, E; Persliden, J

    2009-01-01

    The purpose of this study was to find the optimal settings for lumbar spine radiography with a flat-panel detector. A CDRAD contrast-detail phantom was imaged at various tube potentials, system speeds and filtration settings. Factorial experiments yielded a range of optimized exposure settings, which were submitted to visual grading analysis with images of an Alderson phantom. The first optimized settings involved a system speed increase from 400 to 800. For anteroposterior projection, the optimal tube potential was reduced from the default of 77 kV to 60 kV to give the best image quality without increasing the effective dose, or to 66 kV to give the lowest dose without reducing image quality. For lateral projection, the tube potential was similarly reduced from the default of 90 kV to 70 kV or 77 kV. Visual grading analysis confirmed the results, with significantly better image quality when optimizing for image quality. The study thus shows that the tube potential can be reduced as long as the system speed is increased simultaneously. This leads to a lower effective dose and/or increased image quality depending on the settings chosen. The factorial experiments provided a powerful way to evaluate several parameters concomitantly.

  9. Multidetector-row CT with a 64-row amorphous silicon flat panel detector

    Science.gov (United States)

    Shapiro, Edward G.; Colbeth, Richard E.; Daley, Earl T.; Job, Isaias D.; Mollov, Ivan P.; Mollov, Todor I.; Pavkovich, John M.; Roos, Pieter G.; Star-Lack, Josh M.; Tognina, Carlo A.

    2007-03-01

    A unique 64-row flat panel (FP) detector has been developed for sub-second multidetector-row CT (MDCT). The intent was to explore the image quality achievable with relatively inexpensive amorphous silicon (a-Si) compared to existing diagnostic scanners with discrete crystalline diode detectors. The FP MDCT system is a bench-top design that consists of three FP modules. Each module uses a 30 cm x 3.3 cm a-Si array with 576 x 64 photodiodes. The photodiodes are 0.52 mm x 0.52 mm, which allows for about twice the spatial resolution of most commercial MDCT scanners. The modules are arranged in an overlapping geometry, which is sufficient to provide a full-fan 48 cm diameter scan. Scans were obtained with various detachable scintillators, e.g. ceramic Gd IIO IIS, particle-in-binder Gd IIO IIS:Tb and columnar CsI:Tl. Scan quality was evaluated with a Catphan-500 performance phantom and anthropomorphic phantoms. The FP MDCT scans demonstrate nearly equivalent performance scans to a commercial 16-slice MDCT scanner at comparable 10 - 20 mGy/100mAs doses. Thus far, a high contrast resolution of 15 lp/cm and a low contrast resolution of 5 mm @ 0.3 % have been achieved on 1 second scans. Sub-second scans have been achieved with partial rotations. Since the future direction of MDCT appears to be in acquiring single organ coverage per scan, future efforts are planned for increasing the number of detector rows beyond the current 64- rows.

  10. Image blur in a flat-panel detector due to Compton scattering at its internal mountings

    Science.gov (United States)

    Bub, A.; Gondrom, S.; Maisl, M.; Uhlmann, N.; Arnold, W.

    2007-05-01

    An image-blurring effect observable in digital x-ray flat-panel pixel detectors, used for x-ray computed tomography or radioscopy, has been studied. Our study indicates that the origin of this blurring effect is the Compton scattered radiation within the entrance window, the mounting of the detector scintillator and other parts of the detector. This effect becomes, in particular, noticeable in the presence of a sharp edge of a metallic component being tested, making the scattering in the detector asymmetric.

  11. High-energy X-ray diffraction using the Pixium 4700 flat-panel detector.

    Science.gov (United States)

    Daniels, J E; Drakopoulos, M

    2009-07-01

    The Pixium 4700 detector represents a significant step forward in detector technology for high-energy X-ray diffraction. The detector design is based on digital flat-panel technology, combining an amorphous Si panel with a CsI scintillator. The detector has a useful pixel array of 1910 x 2480 pixels with a pixel size of 154 microm x 154 microm, and thus it covers an effective area of 294 mm x 379 mm. Designed for medical imaging, the detector has good efficiency at high X-ray energies. Furthermore, it is capable of acquiring sequences of images at 7.5 frames per second in full image mode, and up to 60 frames per second in binned region of interest modes. Here, the basic properties of this detector applied to high-energy X-ray diffraction are presented. Quantitative comparisons with a widespread high-energy detector, the MAR345 image plate scanner, are shown. Other properties of the Pixium 4700 detector, including a narrow point-spread function and distortion-free image, allows for the acquisition of high-quality diffraction data at high X-ray energies. In addition, high frame rates and shutterless operation open new experimental possibilities. Also provided are the necessary data for the correction of images collected using the Pixium 4700 for diffraction purposes.

  12. Parameter investigation and first results from a digital flat panel detector with forward bias capability

    Science.gov (United States)

    Starman, Jared; Tognina, Carlo; Virshup, Gary; Star-lack, Josh; Mollov, Ivan; Fahrig, Rebecca

    2008-03-01

    Digital flat panel a-Si x-ray detectors can exhibit image lag of several percent. The image lag can limit the temporal resolution of the detector, and introduce artifacts into CT reconstructions. It is believed that the majority of image lag is due to defect states, or traps, in the a-Si layer. Software methods to characterize and correct for the image lag exist, but they may make assumptions such as the system behaves in a linear time-invariant manner. The proposed method of reducing lag is a hardware solution that makes few additional hardware changes. For pulsed irradiation, the proposed method inserts a new stage in between the readout of the detector and the data collection stages. During this stage the photodiode is operated in a forward bias mode, which fills the defect states with charge. Parameters of importance are current per diode and current duration, which were investigated under light illumination by the following design parameters: 1.) forward bias voltage across the photodiode and TFT switch, 2.) number of rows simultaneously forward biased, and 3.) duration of the forward bias current. From measurements, it appears that good design criteria for the particular imager used are 8 or fewer active rows, 2.9V (or greater) forward bias voltage, and a row frequency of 100 kHz or less. Overall, the forward bias method has been found to reduce first frame lag by as much as 95%. The panel was also tested under x-ray irradiation. Image lag improved (94% reduction), but the temporal response of the scintillator became evident in the turn-on step response.

  13. Neural network-based detection of pulmonary nodules on chest radiography; Identificazione mediante reti neurali dei noduli polmonari nel radiogramma del torace

    Energy Technology Data Exchange (ETDEWEB)

    Coppini, G. [Consiglio Nazionale delle Ricerche, Pisa (Italy). Ist. di Fisiologia Patologica; Valli, G. [Florence Univ., Florence (Italy). Dipt. di Ingegneria Elettronica; Falchini, M.; Stecco, A.; Bindi, A.; Carmignani, L. [Florence Univ., Florence (Italy). Dipt. di Fisiopatologia Clinica, Sezione di Radiodiagnostica

    1999-10-01

    In this report are investigated the capabilities of an artificial neural network-based Computer-Aided Diagnosis (CAD) system in improving early detection of pulmonary nodules on chest radiographs. [Italian] Valutazione di un sistema di riconoscimento automatico basato sulla tecnologia delle reti neruali artificiali per migliorare le possibilita' di rivelazione precoce dei noduli polmonari sul radiogramma toracico.

  14. Varied tube potential with constant effective dose at lumbar spine radiography using a flat-panel digital detector.

    Science.gov (United States)

    Geijer, Håkan; Persliden, Jan

    2005-01-01

    The purpose of the study was to evaluate the image quality at different tube potential (kV) settings using anteroposterior lumbar spine radiography as a model. An Alderson phantom was used with a flat-panel detector. The tube potential varied between 48 and 125 kV while the tube charge (mAs) was adjusted to keep an effective dose of 0.11 mSv. Image quality was assessed with a visual grading analysis and with a CDRAD contrast-detail phantom together with a computer program. The VGA showed inferior image quality for the higher kV settings, > or =96 kVwith similar results for the contrast-detail phantom. When keeping the effective dose fixed, it seems beneficial to reduce kV to get the best image quality despite the fact that the mAs is not as high as with automatic exposure. However, this cannot be done with automatic exposure, which is set for a constant detector dose.

  15. Image quality of a Konica Regius 336 digital system in chest radiography; Qualita' dell'immagine di un sistema digitale Konica Regius 336 per radiologia toracica

    Energy Technology Data Exchange (ETDEWEB)

    Ostinelli, A.; Frigerio, M.; Monti, A.F.; Gelosa, S.; Tognoli, P.; Perniola, N. [Azienda Ospedaliera S. Anna, Como (Italy). Servizio di Fisica Sanitaria; Gozzi, G. [Azienda Ospedaliera S. Anna, Como (Italy). Servizio di Radiologia

    2000-06-01

    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. [Italian] I sistemi radiografici digitali offrono la possibilita' di ottimizzare l'esecuzione, la visualizzazione e l'archiviazione dell'immagine radiologica. Poiche' presso il Servizio di Radiologia dell'Azienda Ospedaliera S. Anna

  16. Chest MRI

    Science.gov (United States)

    Nuclear magnetic resonance - chest; Magnetic resonance imaging - chest; NMR - chest; MRI of the thorax; Thoracic MRI ... healthy enough to filter the contrast. During the MRI, the person who operates the machine will watch ...

  17. Chest wall, lung, and pleural space trauma.

    Science.gov (United States)

    Miller, Lisa A

    2006-03-01

    Chest radiographs frequently underestimate the severity and extent of chest trauma and, in some cases, fail to detect the presence of injury. CT is more sensitive than chest radiography in the detection of pulmonary, pleural, and osseous abnormalities in the patient who has chest trauma. With the advent of multidetector CT (MDCT), high-quality multiplanar reformations are obtained easily and add to the diagnostic capabilities of MDCT. This article reviews the radiographic and CT findings of chest wall, pleural, and pulmonary injuries that are seen in the patient who has experienced blunt thoracic trauma.

  18. Neutron Radiography

    Science.gov (United States)

    Heller, A. K.; Brenizer, J. S.

    Neutron radiography and its related two-dimensional (2D) neutron imaging techniques have been established as invaluable nondestructive inspection methods and quantitative measurement tools. They have been used in a wide variety of applications ranging from inspection of aircraft engine turbine blades to study of two-phase fluid flow in operating proton exchange membrane fuel cells. Neutron radiography is similar to X-ray radiography in that the method produces a 2D attenuation map of neutron radiation that has penetrated the object being examined. However, the images produced differ and are often complementary due to the differences between X-ray and neutron interaction mechanisms. The uses and types of 2D neutron imaging have expanded over the past 15 years as a result of advances in imaging technology and improvements in neutron generators/sources and computers. Still, high-intensity sources such as those from reactors and spallation neutron sources, together with conventional film radiography, remain the mainstay of high-resolution, large field-of-view neutron imaging. This chapter presents a summary of the history, methods, and related variations of neutron radiography techniques.

  19. Light emission efficiency and imaging performance of Gd2O2S: Eu powder scintillator under x-ray radiography conditions.

    Science.gov (United States)

    Michail, C M; Fountos, G P; Liaparinos, P F; Kalyvas, N E; Valais, I; Kandarakis, I S; Panayiotakis, G S

    2010-07-01

    To evaluate Gd2O2S:Eu powder phosphor as a radiographic image receptor and to compare it to phosphors often used in radiography. Gd2O2S:Eu is nonhygroscopic, emitting red light with decay time close to that of Gd2O2S:Tb. The light intensity emitted per unit of x-ray exposure rate (absolute luminescence efficiency) was measured for laboratory prepared screens with coating thicknesses of 33.1, 46.4, 63.1, 78.3, and 139.8 mg/cm2 and tube voltages ranging from 50 to 140 kVp. Parameters related to image quality such as the modulation transfer function (MTF) and the detective quantum efficiency (DQE) were also experimentally examined. In addition, a previously validated Monte Carlo code was used to estimate intrinsic x-ray absorption and optical properties, as well as the MTF and the Swank factor (I) of the Gd2O2S:Eu scintillators. Gd2O2S:Eu light intensity was found higher than that of single CsI:T1 crystal for tube voltages up to 100 kVp. The MTF and the DQE were found to be comparable with those of Gd2O2S:Tb and CsI:T1 screens. MTF estimated by the Monte Carlo code was found very close to the experimental MTF values. Gd2O2S:Eu showed peak emission in the wavelength range 620-630 nm. Its emission spectrum was excellently matched to various optical detectors (photodiodes, photocathodes, CCDs, and CMOS) employed in flat panel detectors. Gd2O2S:Eu is an efficient phosphor potentially well suited to radiography and especially to some digital detectors sensitive to red light.

  20. Development of a prototype chest digital tomosynthesis (CDT) R/F system with fast image reconstruction using graphics processing unit (GPU) programming

    Science.gov (United States)

    Choi, Sunghoon; Lee, Seungwan; Lee, Haenghwa; Lee, Donghoon; Choi, Seungyeon; Shin, Jungwook; Seo, Chang-Woo; Kim, Hee-Joung

    2017-03-01

    Digital tomosynthesis offers the advantage of low radiation doses compared to conventional computed tomography (CT) by utilizing small numbers of projections ( 80) acquired over a limited angular range. It produces 3D volumetric data, although there are artifacts due to incomplete sampling. Based upon these characteristics, we developed a prototype digital tomosynthesis R/F system for applications in chest imaging. Our prototype chest digital tomosynthesis (CDT) R/F system contains an X-ray tube with high power R/F pulse generator, flat-panel detector, R/F table, electromechanical radiographic subsystems including a precise motor controller, and a reconstruction server. For image reconstruction, users select between analytic and iterative reconstruction methods. Our reconstructed images of Catphan700 and LUNGMAN phantoms clearly and rapidly described the internal structures of phantoms using graphics processing unit (GPU) programming. Contrast-to-noise ratio (CNR) values of the CTP682 module of Catphan700 were higher in images using a simultaneous algebraic reconstruction technique (SART) than in those using filtered back-projection (FBP) for all materials by factors of 2.60, 3.78, 5.50, 2.30, 3.70, and 2.52 for air, lung foam, low density polyethylene (LDPE), Delrin® (acetal homopolymer resin), bone 50% (hydroxyapatite), and Teflon, respectively. Total elapsed times for producing 3D volume were 2.92 s and 86.29 s on average for FBP and SART (20 iterations), respectively. The times required for reconstruction were clinically feasible. Moreover, the total radiation dose from our system (5.68 mGy) was lower than that of conventional chest CT scan. Consequently, our prototype tomosynthesis R/F system represents an important advance in digital tomosynthesis applications.

  1. Response of a CsI/amorphous-Si flat panel detector as function of incident x-ray angle

    Science.gov (United States)

    Tkaczyk, J. Eric; Claus, Bernhard; Trotter, Dinko Gonzalez; Eberhard, J. W.

    2006-03-01

    Two mechanisms for MTF dependence on incident x-ray angle are demonstrated by an experimental technique that separates the two phenomena. The dominant effect is that travel of x-ray photons through the scintillator at non-normal incidence involves an in-plane component. This mechanism leads to a significant but deterministic blurring of the incident image, but has no effect on the noise transfer characteristics of the detector. A secondary effect is that at large angles to the surface normal, x-ray-to-optical conversion occurs at positions in the scintillator further away from the photodiode surface. This leads to a small net decrease in MTF and NPS at angles above 60 degrees. The deterministic character of the angular dependence of gain, MTF and NPS leads to the conclusion that sufficient angular range can be supported by this detector construction. Excellent functionality in the context of tomography is expected.

  2. Full breast digital mammography with an amorphous silicon-based flat panel detector: Physical characteristics of a clinical prototype

    OpenAIRE

    2000-01-01

    The physical characteristics of a clinical prototype amorphous silicon-based flat panel imager for full-breast digital mammography have been investigated. The imager employs a thin thallium doped CsI scintillator on an amorphous silicon matrix of detector elements with a pixel pitch of 100 μm. Objective criteria such as modulation transfer function (MTF), noise power spectrum, detective quantum efficiency (DQE), and noise equivalent quanta were employed for this evaluation. The presampling MT...

  3. Full breast digital mammography with an amorphous silicon-based flat panel detector: physical characteristics of a clinical prototype.

    Science.gov (United States)

    Vedantham, S; Karellas, A; Suryanarayanan, S; Albagli, D; Han, S; Tkaczyk, E J; Landberg, C E; Opsahl-Ong, B; Granfors, P R; Levis, I; D'Orsi, C J; Hendrick, R E

    2000-03-01

    The physical characteristics of a clinical prototype amorphous silicon-based flat panel imager for full-breast digital mammography have been investigated. The imager employs a thin thallium doped CsI scintillator on an amorphous silicon matrix of detector elements with a pixel pitch of 100 microm. Objective criteria such as modulation transfer function (MTF), noise power spectrum, detective quantum efficiency (DQE), and noise equivalent quanta were employed for this evaluation. The presampling MTF was found to be 0.73, 0.42, and 0.28 at 2, 4, and 5 cycles/mm, respectively. The measured DQE of the current prototype utilizing a 28 kVp, Mo-Mo spectrum beam hardened with 4.5 cm Lucite is approximately 55% at close to zero spatial frequency at an exposure of 32.8 mR, and decreases to approximately 40% at a low exposure of 1.3 mR. Detector element nonuniformity and electronic gain variations were not significant after appropriate calibration and software corrections. The response of the imager was linear and did not exhibit signal saturation under tested exposure conditions.

  4. Cone-beam CT with a flat-panel detector: From image science to image-guided surgery

    Energy Technology Data Exchange (ETDEWEB)

    Siewerdsen, Jeffrey H., E-mail: jeff.siewerdsen@jhu.edu [Department of Biomedical Engineering, Johns Hopkins University, Traylor Building, Room 718, 720 Rutland Avenue, Baltimore, MD 21205 (United States)

    2011-08-21

    The development of large-area flat-panel X-ray detectors (FPDs) has spurred investigation in a spectrum of advanced medical imaging applications, including tomosynthesis and cone-beam CT (CBCT). Recent research has extended image quality metrics and theoretical models to such applications, providing a quantitative foundation for the assessment of imaging performance as well as a general framework for the design, optimization, and translation of such technologies to new applications. For example, cascaded systems models of the Fourier domain metrics, such as noise-equivalent quanta (NEQ), have been extended to these modalities to describe the propagation of signal and noise through the image acquisition and reconstruction chain and to quantify the factors that govern spatial resolution, image noise, and detectability. Moreover, such models have demonstrated basic agreement with human observer performance for a broad range of imaging conditions and imaging tasks. These developments in image science have formed a foundation for the knowledgeable development and translation of CBCT to new applications in image-guided interventions-for example, CBCT implemented on a mobile surgical C-arm for intraoperative 3D imaging. The ability to acquire high-quality 3D images on demand during surgical intervention overcomes conventional limitations of surgical guidance in the context of preoperative images alone. A prototype mobile C-arm developed in academic-industry partnership demonstrates CBCT with low radiation dose, sub-mm spatial resolution, and soft-tissue visibility potentially approaching that of diagnostic CT. Integration of the 3D imaging system with real-time tracking, deformable registration, endoscopic video, and 3D visualization offers a promising addition to the surgical arsenal in interventions ranging from head-and-neck/skull base surgery to spine, orthopaedic, thoracic, and abdominal surgeries. Cadaver studies show the potential for significant boosts in surgical performance under CBCT guidance, and early clinical trials demonstrate feasibility, workflow, and image quality within the surgical theatre.

  5. Cone-beam CT with a flat-panel detector: From image science to image-guided surgery

    Science.gov (United States)

    Siewerdsen, Jeffrey H.

    2011-08-01

    The development of large-area flat-panel X-ray detectors (FPDs) has spurred investigation in a spectrum of advanced medical imaging applications, including tomosynthesis and cone-beam CT (CBCT). Recent research has extended image quality metrics and theoretical models to such applications, providing a quantitative foundation for the assessment of imaging performance as well as a general framework for the design, optimization, and translation of such technologies to new applications. For example, cascaded systems models of the Fourier domain metrics, such as noise-equivalent quanta (NEQ), have been extended to these modalities to describe the propagation of signal and noise through the image acquisition and reconstruction chain and to quantify the factors that govern spatial resolution, image noise, and detectability. Moreover, such models have demonstrated basic agreement with human observer performance for a broad range of imaging conditions and imaging tasks. These developments in image science have formed a foundation for the knowledgeable development and translation of CBCT to new applications in image-guided interventions—for example, CBCT implemented on a mobile surgical C-arm for intraoperative 3D imaging. The ability to acquire high-quality 3D images on demand during surgical intervention overcomes conventional limitations of surgical guidance in the context of preoperative images alone. A prototype mobile C-arm developed in academic-industry partnership demonstrates CBCT with low radiation dose, sub-mm spatial resolution, and soft-tissue visibility potentially approaching that of diagnostic CT. Integration of the 3D imaging system with real-time tracking, deformable registration, endoscopic video, and 3D visualization offers a promising addition to the surgical arsenal in interventions ranging from head-and-neck/skull base surgery to spine, orthopaedic, thoracic, and abdominal surgeries. Cadaver studies show the potential for significant boosts in surgical performance under CBCT guidance, and early clinical trials demonstrate feasibility, workflow, and image quality within the surgical theatre.

  6. Patient-specific scatter correction for flat-panel detector-based cone-beam CT imaging.

    Science.gov (United States)

    Zhao, Wei; Brunner, Stephen; Niu, Kai; Schafer, Sebastian; Royalty, Kevin; Chen, Guang-Hong

    2015-02-07

    A patient-specific scatter correction algorithm is proposed to mitigate scatter artefacts in cone-beam CT (CBCT). The approach belongs to the category of convolution-based methods in which a scatter potential function is convolved with a convolution kernel to estimate the scatter profile. A key step in this method is to determine the free parameters introduced in both scatter potential and convolution kernel using a so-called calibration process, which is to seek for the optimal parameters such that the models for both scatter potential and convolution kernel is able to optimally fit the previously known coarse estimates of scatter profiles of the image object. Both direct measurements and Monte Carlo (MC) simulations have been proposed by other investigators to achieve the aforementioned rough estimates. In the present paper, a novel method has been proposed and validated to generate the needed coarse scatter profile for parameter calibration in the convolution method. The method is based upon an image segmentation of the scatter contaminated CBCT image volume, followed by a reprojection of the segmented image volume using a given x-ray spectrum. The reprojected data is subtracted from the scatter contaminated projection data to generate a coarse estimate of the needed scatter profile used in parameter calibration. The method was qualitatively and quantitatively evaluated using numerical simulations and experimental CBCT data acquired on a clinical CBCT imaging system. Results show that the proposed algorithm can significantly reduce scatter artefacts and recover the correct CT number. Numerical simulation results show the method is patient specific, can accurately estimate the scatter, and is robust with respect to segmentation procedure. For experimental and in vivo human data, the results show the CT number can be successfully recovered and anatomical structure visibility can be significantly improved.

  7. Automatic hanging protocol for chest radiographs

    Science.gov (United States)

    Luo, Hui; Hao, Wei; Cornelius, Craig

    2005-04-01

    Chest radiography is one of the most widely used techniques in diagnostic imaging. It makes up at least one third of all conventional diagnostic radiographic procedures in hospitals. However, in both film-screen and computed radiography, images are often digitized with the view and orientation unknown or mislabeled, which causes inefficiency in displaying them in the picture archive and communication system (PACS). Hence, the goal of this work is to provide a robust, efficient, and automatic hanging protocol for chest radiographs. To achieve it, the method star ts with recognition by extracting a set of distinctive features from chest radiographs. Next, a well-defined probabilistic classifier is used to train and classify the radiographs. Identifying the orientation of the radiographs is performed by an efficient algorithm which locates the neck, heart, and abdomen positions in radiographs. The initial experiment was performed on radiographs collected from daily routine chest exams in hospitals, and it has shown promising results.

  8. Tuberculous spondylitis presenting as severe chest pain

    Directory of Open Access Journals (Sweden)

    Martha A. Kaeser

    2012-04-01

    Full Text Available This case report describes a 32-year-old male who presented to an emergency department with severe chest pain and a history of cough, fever, night sweats, loss of appetite and weight. Chest radiography revealed a left upper lobe consolidation and multiple compression deformities in the thoracic spine. Magnetic resonance imaging demonstrated significant kyphosis and vertebral plana at two thoracic levels. Anterior compression of the spinal cord and adjacent soft tissue masses were also noted.

  9. Application of mobile digital radiography in chest health examination outside the hospital%车载DR系统在院外大规模胸部健康体检中的应用价值

    Institute of Scientific and Technical Information of China (English)

    俞新华; 黎惠如; 宋敏; 曾庆之

    2014-01-01

    目的:评价车载直接数字摄影技术(DR)在院外大规模胸部健康体检中的应用价值。方法随机抽取我院2012年6~12月车载DR图像和车载传统X线摄影胶片各1000例及同时段车载X线透视1000例受检者的检查结果进行对比、分析图象质量、病变检出率及受检者的受照剂量。结果车载DR图像质量好,清晰度高,DR组甲级片率(64.2%)明显高于传统X线摄影组(43.1%),差异有统计学意义(P<0.05),且废片率为0,优于车载传统X摄影;病变检出率车载DR为7.9%,均比传统X摄影的4.6%及X线透视的3.1%高,差异有统计学意义(P<0.05),且图像可长期保存,便于对照;受检者个人受照剂量车载DR为(0.50±0.04) mGy,明显低于传统X线摄影的(2.35±0.70) mGy和X透视的(8.40±1.08) mGy,差异有统计学意义(P<0.05)。结论车载DR使用灵活、方便、高效,病变检出率高,而且明显降低受检者的照射剂量,安全性高,可作为院外健康体检首选的X影像设备之一。%Objective To analyze the application value of mobile digital radiography (DR) in chest health ex-amination outside the hospital. Methods A comparative study of mobile DR (1 000 cases), mobile traditional X-ray photography (1 000 cases) and fluoroscopy (1 000 cases) from June 2012 to December 2012 were performed to ana-lyze their image quality, detection rate of lesions and exposure dose. Results Mobile DR images were of good quali-ty, with high-definition. Class A piece rate of DR group (64.2%) was significantly higher than that of traditional X-ray photography group (43.1%), P<0.05. The scrap rate of DR group was 0, superior to the traditional X-ray photography group. The lesion detection rate on-board of DR group was 7.9%, significantly higher than traditional X-ray photogra-phy group (4.6%) and X-ray fluoroscopy group (3.1%), P<0.05. And the images of mobile DR can be preserved for a long term and were easy to control. Client

  10. [Chest pain].

    Science.gov (United States)

    Horn, Benedikt

    2015-01-01

    Chest pain in ambulatory setting is predominantly not heart-associated. Most patients suffer from muskuloskeletal or functional (psychogenic) chest pain. Differential diagnosis covers aortic dissection, rib-fracture, shingles, GERD, Tietze-Syndrome, pulmonary embolism, pleuritis, pneumothorax, pleurodynia and metastatic disease. In most cases history, symptoms and signs allow a clinical diagnosis of high pretest-probability.

  11. FLAIL CHEST

    Directory of Open Access Journals (Sweden)

    Anton Crnjac

    2003-12-01

    Full Text Available Background. Major thoracic trauma is consistent with high mortality rate because of associated injuries of vital thoracic organs and dangerous complications. The flail chest occurs after disruption of the skeletal continuity of chest wall and demands because of its pathophysiological complexity rapid and accurate diagnosis and treatment.Conclusions. Basic pathophysiological mechanism of the flail chest is respiratory distress, which is provoked by pulmonary contusions and paradoxical chest wall motion. The treatment should be pointed to improvement and support of respiratory functions and include aggressive pain control, pulmonary physiotherapy and selective mechanical ventilation. Views about operative fixation of the flail chest are still controversial. Neither mortality rate neither long-term disability are improved after operative fixation.

  12. Plate-specific gain map correction for the improvement of detective quantum efficiency in computed radiography

    Energy Technology Data Exchange (ETDEWEB)

    Schnell, Erich A.; Samei, Ehsan; Dobbins, James T. [Ravin Advanced Imaging Laboratories, Department of Radiology and Medical Physics Graduate Program, Duke University Medical Center, North Carolina 27705 (United States); Ravin Advanced Imaging Laboratories, Departments of Radiology, Biomedical Engineering, and Physics, and Medical Physics Graduate Program, Duke University Medical Center, North Carolina 27705 (United States)

    2012-03-15

    Purpose: The purpose of this work is to improve the noise power spectrum (NPS), and thus the detective quantum efficiency (DQE), of computed radiography (CR) images by correcting for spatial gain variations specific to individual imaging plates. CR devices have not traditionally employed gain-map corrections, unlike the case with flat-panel detectors, because of the multiplicity of plates used with each reader. The lack of gain-map correction has limited the DQE(f) at higher exposures with CR. This current work describes a feasible solution to generating plate-specific gain maps. Methods: Ten high-exposure open field images were taken with an RQA5 spectrum, using a sixth generation CR plate suspended in air without a cassette. Image values were converted to exposure, the plates registered using fiducial dots on the plate, the ten images averaged, and then high-pass filtered to remove low frequency contributions from field inhomogeneity. A gain-map was then produced by converting all pixel values in the average into fractions with mean of one. The resultant gain-map of the plate was used to normalize subsequent single images to correct for spatial gain fluctuation. To validate performance, the normalized NPS (NNPS) for all images was calculated both with and without the gain-map correction. Variations in the quality of correction due to exposure levels, beam voltage/spectrum, CR reader used, and registration were investigated. Results: The NNPS with plate-specific gain-map correction showed improvement over the noncorrected case over the range of frequencies from 0.15 to 2.5 mm{sup -1}. At high exposure (40 mR), NNPS was 50%-90% better with gain-map correction than without. A small further improvement in NNPS was seen from carefully registering the gain-map with subsequent images using small fiducial dots, because of slight misregistration during scanning. Further improvement was seen in the NNPS from scaling the gain map about the mean to account for different beam

  13. Plate-specific gain map correction for the improvement of detective quantum efficiency in computed radiography.

    Science.gov (United States)

    Schnell, Erich A; Samei, Ehsan; Dobbins, James T

    2012-03-01

    The purpose of this work is to improve the noise power spectrum (NPS), and thus the detective quantum efficiency (DQE), of computed radiography (CR) images by correcting for spatial gain variations specific to individual imaging plates. CR devices have not traditionally employed gain-map corrections, unlike the case with flat-panel detectors, because of the multiplicity of plates used with each reader. The lack of gain-map correction has limited the DQE(f) at higher exposures with CR. This current work describes a feasible solution to generating plate-specific gain maps. Ten high-exposure open field images were taken with an RQA5 spectrum, using a sixth generation CR plate suspended in air without a cassette. Image values were converted to exposure, the plates registered using fiducial dots on the plate, the ten images averaged, and then high-pass filtered to remove low frequency contributions from field inhomogeneity. A gain-map was then produced by converting all pixel values in the average into fractions with mean of one. The resultant gain-map of the plate was used to normalize subsequent single images to correct for spatial gain fluctuation. To validate performance, the normalized NPS (NNPS) for all images was calculated both with and without the gain-map correction. Variations in the quality of correction due to exposure levels, beam voltage/spectrum, CR reader used, and registration were investigated. The NNPS with plate-specific gain-map correction showed improvement over the noncorrected case over the range of frequencies from 0.15 to 2.5 mm(-1). At high exposure (40 mR), NNPS was 50%-90% better with gain-map correction than without. A small further improvement in NNPS was seen from carefully registering the gain-map with subsequent images using small fiducial dots, because of slight misregistration during scanning. Further improvement was seen in the NNPS from scaling the gain map about the mean to account for different beam spectra. This study

  14. Industrial radiographies

    CERN Multimedia

    2005-01-01

    The Radiation Protection group wishes to remind CERN staff responsible for contractors performing X-ray inspections on the CERN sites that the firms must apply the legislation in force in their country of origin, in particular with regard to the prevention of risks relating to ionizing radiation. Industrial radiography firms called on to work on the CERN sites must also comply with the rules laid down in CERN's Radiation Safety Manual and be registered in the relevant CERN database. Since CERN is responsible for safety on its own site, a number of additional rules have been laid down for this kind of work, as set out in Radiation Protection Procedure PRP30 https://edms.cern.ch/file/346848/LAST_RELEASED/PRP30.pdf The CERN Staff Member responsible for the contract shall register the company and issue notification that an X-ray inspection is to be performed via the web interface at the following address: http://cern.ch/rp-radio

  15. [Chest trauma].

    Science.gov (United States)

    Freixinet Gilart, Jorge; Ramírez Gil, María Elena; Gallardo Valera, Gregorio; Moreno Casado, Paula

    2011-01-01

    Chest trauma is a frequent problem arising from lesions caused by domestic and occupational activities and especially road traffic accidents. These injuries can be analyzed from distinct points of view, ranging from consideration of the most severe injuries, especially in the context of multiple trauma, to the specific characteristics of blunt and open trauma. In the present article, these injuries are discussed according to the involvement of the various thoracic structures. Rib fractures are the most frequent chest injuries and their diagnosis and treatment is straightforward, although these injuries can be severe if more than three ribs are affected and when there is major associated morbidity. Lung contusion is the most common visceral lesion. These injuries are usually found in severe chest trauma and are often associated with other thoracic and intrathoracic lesions. Treatment is based on general support measures. Pleural complications, such as hemothorax and pneumothorax, are also frequent. Their diagnosis is also straightforward and treatment is based on pleural drainage. This article also analyzes other complex situations, notably airway trauma, which is usually very severe in blunt chest trauma and less severe and even suitable for conservative treatment in iatrogenic injury due to tracheal intubation. Rupture of the diaphragm usually causes a diaphragmatic hernia. Treatment is always surgical. Myocardial contusions should be suspected in anterior chest trauma and in sternal fractures. Treatment is conservative. Other chest injuries, such as those of the great thoracic and esophageal vessels, are less frequent but are especially severe.

  16. Accurate MTF measurement in digital radiography using noise response

    Energy Technology Data Exchange (ETDEWEB)

    Kuhls-Gilcrist, Andrew; Jain, Amit; Bednarek, Daniel R.; Hoffmann, Kenneth R.; Rudin, Stephen [Toshiba Stroke Research Center, University at Buffalo, State University of New York, Biomedical Research Building, Room 445, 3435 Main Street, Buffalo, New York 14214 (United States)

    2010-02-15

    Purpose: The authors describe a new technique to determine the system presampled modulation transfer function (MTF) in digital radiography using only the detector noise response. Methods: A cascaded-linear systems analysis was used to develop an exact relationship between the two-dimensional noise power spectrum (NPS) and the presampled MTF for a generalized detector system. This relationship was then utilized to determine the two-dimensional presampled MTF. For simplicity, aliasing of the correlated noise component of the NPS was assumed to be negligible. Accuracy of this method was investigated using simulated images from a simple detector model in which the ''true'' MTF was known exactly. Measurements were also performed on three detector technologies (an x-ray image intensifier, an indirect flat panel detector, and a solid state x-ray image intensifier), and the results were compared using the standard edge-response method. Flat-field and edge images were acquired and analyzed according to guidelines set forth by the International Electrotechnical Commission, using the RQA 5 spectrum. Results: The presampled MTF determined using the noise-response method for the simulated detector system was in close agreement with the true MTF with an averaged percent difference of 0.3% and a maximum difference of 1.1% observed at the Nyquist frequency (f{sub N}). The edge-response method of the simulated detector system also showed very good agreement at lower spatial frequencies (less than 0.5 f{sub N}) with an averaged percent difference of 1.6% but showed significant discrepancies at higher spatial frequencies (greater than 0.5 f{sub N}) with an averaged percent difference of 17%. Discrepancies were in part a result of noise in the edge image and phasing errors. For all three detector systems, the MTFs obtained using the two methods were found to be in good agreement at spatial frequencies less than 0.5 f{sub N} with an averaged percent difference of 3

  17. Comparison of ultrasonography and radiography in diagnosis of rib fractures.

    Science.gov (United States)

    Pishbin, Elham; Ahmadi, Koorosh; Foogardi, Molood; Salehi, Maryam; Seilanian Toosi, Farrokh; Rahimi-Movaghar, Vafa

    2017-08-01

    Rib fractures are the most common skeletal thoracic injuries resulting from blunt chest trauma. Half of the rib fractures are not detected upon a precise physical evaluation and radiographs. Recently ultrasonography (USG) has been investigated to detect rib fractures. But based on literature the usefulness of USG varies widely. This study was conducted to investigate the role of USG in the detection of possible rib fractures in comparison with radiography. In this cross-sectional study, consecutive patients with minor blunt chest trauma and suspected rib fractures presenting in Imam Reza Hospital located in Mashhad-Iran, between April 2013 and October 2013 were assessed by USG and radiography. The radiography was performed in a posteroanterior (PA) chest projection and oblique rib view centered over the area of trauma. The time duration spent in taking USG and radiography were recorded. The prevalence and location of fractures revealed by USG and radiography were compared. Sixty-one suspected patients were assessed. The male to female ratio was 2.4:1 (43 men and 18 women) with a mean ± SD age of (44.3 ± 19.7) years. There were totally 59 rib fractures in 38 (62.3%) patients based on radiography and USG, while 23 (37.7%) patients had no diagnostic evidence of rib lesions. USG revealed 58 rib fractures in 33 (54.1%) of 61 suspected patients and radiographs revealed 32 rib fractures in 20 (32.8%) of 61 patients. A total of 58 (98.3%) rib fractures were detected by USG, whereas oblique rib view and PA chest radiography showed 27 (45.8%) and 24 (40.7%) rib fractures, respectively. The average duration of USG was (12 ± 3) min (range 7-17 min), whereas the duration of radiography was (27 ± 6) min (range 15-37 min). The kappa coefficient showed a low level of agreement between both USG and PA chest radiography (kappa coefficient = 0.28), and between USG and oblique rib view (kappa coefficient = 0.32). USG discloses more fractures than radiography in

  18. A pilot study evaluating erect chest imaging in children, using the Lodox Statscan digital X-ray machine

    OpenAIRE

    2009-01-01

    ABSTRACT Background: Chest radiography accounts for a significant proportion of ionising radiation in children. The radiation dose of radiographs performed on the Lodox Statscan system has been shown to be lower than that of a computed radiography (CR) system. The role of the Lodox Statscan (hereafter referred to as the Statscan) in routine erect chest radiography in children has not been evaluated. Objective: To evaluate the image quality and diagnostic accuracy of erect paedi...

  19. International Neutron Radiography Newsletter

    DEFF Research Database (Denmark)

    Domanus, Joseph Czeslaw

    1986-01-01

    At the First World Conference on Neutron Radiography i t was decided to continue the "Neutron Radiography Newsletter", published previously by J.P. Barton, as the "International Neutron Radiography Newsletter" (INRNL), with J.C. Doraanus as editor. The British Journal of Non-Destructive Testing...

  20. Increasing mobile radiography productivity.

    Science.gov (United States)

    Wong, Edward; Lung, Ngan Tsz; Ng, Kris; Jeor, Patrick

    2013-01-01

    Mobile radiography using computed radiography (CR) cassettes is a common equipment combination with a workflow bottleneck limited by location of CR readers. Advent of direct digital radiography (DDR) mobile x-ray machines removes this limitation by immediate image review and quality control. Through the use of key performance indicators (KPIs), the increase in efficiency can be quantified.

  1. The Enhanced Workflow and Efficiency of the Wireless Local Area Network (WLAN)-Based Direct Digital Radiography (DDR) Portable Radiography.

    Science.gov (United States)

    Ngan, Tsz-Lung; Wong, Edward Ting-Hei; Ng, Kris Lap-Shun; Jeor, Patrick Kwok-Shing; Lo, Gladys Goh

    2015-06-01

    With the implementation of the PACS in the hospital, there is an increasing demand from the clinicians for immediate access and display of radiological images. Recently, our hospital has installed the first wireless local area network (WLAN)-based direct digital radiography (DDR) portable radiography system. The DDR portable radiography system allows wireless retrieval of modality worklist and wireless transmission of portable X-ray image on the console to the Picture Archiving and Communication System (PACS), via WLAN connection of wireless fidelity (Wi-Fi). The aim of this study was to analyze the workflow and performance between the WLAN-based DDR portable radiography system and the old practice using conventional portable X-ray machine with computed radiography (CR) system. A total of 190 portable chest X-ray examinations were evaluated and timed, using the conventional portable X-ray machine with CR from March to April of 2012 and using the new DDR portable radiography system on December of 2012 (n = 97 for old system and n = 93 for DDR portable system). The time interval of image becoming available to the PACS using the WLAN-based DDR portable radiography system was significantly shorter than that of the old practice using the conventional portable X-ray machine with CR (6.8 ± 2.6 min for DDR portable system; 23 ± 10.2 min for old system; p DDR portable radiography system can enhance the workflow of portable radiography by reduction of procedural steps.

  2. Diagnostic Utility of Chest X-rays in Neonatal Respiratory Distress: Determining the Sensitivity and Specificity

    Directory of Open Access Journals (Sweden)

    Hassan Mottaghi Moghadam shahri

    2014-11-01

    Full Text Available Background: Chest radiography is one of the most usual diagnostic tools for respiratory distress. Objective: The purpose of this study is to assess the specificity, sensitivity and clinical value of chest radiography of neonates with respiratory distress.Patients and Methods: A descriptive- analytical study was conducted on 102 neonates that were in neonatal intensive care unit of Imam Reza and 22 Bahman Hospitals because of respiratory distress. After confirming the neonate's respiratory distress and taking chest radiography, the radiography was described by a radiologist and final diagnosis was confirmed. Results: Most of the neonates (64.7% were born with caesarian section and were premature (78.4%. Respiratory distress syndrome (RDS was the most common reason for respiratory distress (38.2%. Chest radiography had the most sensitivity and specificity in pneumothorax and hernia (100%. For pneumosepsis, radiography had 73% sensitivity and 87% specificity, for RDS the sensitivity and specificity were 35% and 82% respectively, for congenital heart disease sensitivity of zero and specificity of 98% and for Transient tachypnea of neonates (TTN sensitivity of zero and specificity of 100%. The conformity of clinical and radiography was also calculated as 79.4% in respiratory distress Discussion and Conclusion: Although chest radiography is used as one of the most usual and accessible diagnostic tools in respiratory distress syndrome, but inaccurate specificity and sensitivity in some disease must be considered, especially in neonates.

  3. Acute, non traumatic patterns in chest radiography of children. Recognition and understanding of radiographic appearances; Akute, nicht traumabedingte Veraenderungen des unteren Respirationstraktes des Kindes im Thoraxroentgen. Erkennen und Verstehen radiologischer Veraenderungen

    Energy Technology Data Exchange (ETDEWEB)

    Puig, S.; Hoermann, M.; Schibany, N.; Ponhold, W. [Universitaetsklinik fuer Radiodiagnostik, Wien (Austria); Sandstroem, S. [Bild o Funktionsdiagnostisk Centrum, Universitetssjukhus, Lund (Sweden)

    2002-03-01

    The diagnosis of acute, non-traumatic diseases of the lower respiratory tract requires exact knowledge of the specific anatomy, physiology and pathology of the pediatric chest. The absolutely and relatively smaller airways, as compared with those of adults, and the undeveloped collateral ventilation result in radiological appearances that are unique in children. Viral pneumonia is predominant only in small children up to an age of 2 years. With increasing age, there is a higher incidence of bacterial pneumonia. The differentiation of viral and bacterial etiology of a pneumonia is not possible on the basis of chest radiographs. In acute pediatric imaging, possible aspiration of foreign bodies has to be considered. Since most foreign bodies cannot be detected radiographically, indirect features such as hyperinflation or mediastinal shifts have to be evaluated. Primary lung tumors are rare in children. More common are metastases with known primary tumors. Neuroblastoma or lymphomas may mimic intrapulmonary pathologies. (orig.) [German] Die Diagnostik akuter, nicht traumabedingter Erkrankungen des unteren Respirationstraktes erfordert genaue Kenntnisse der speziellen Anatomie, Physiologie und Pathologie der kindlichen Lunge. Die absolut und auch relativ kleineren Luftwege im Vergleich zum Erwachsenen, aber auch der noch nicht ausgebildete Kollateralkreislauf fuehren zu pulmonalen Veraenderungen, wie sie nur beim Kind vorkommen. Bei den Pneumonien sind Viren nur bei Kleinkindern bis zum 2. Lebensjahr praedominant. Mit zunehmendem Alter treten Bakterien immer mehr in den Vordergrund. Eine Unterscheidung zwischen viralem und bakteriellem Erreger ist im Thoraxroentgen nicht moeglich. Haeufig ist auch eine fragliche Fremdkoerperaspiration abzuklaeren. Da die meisten Fremdkoerper nicht roentgendicht sind, muss auf indirekte Zeichen wie Ueberblaehung und Mediastinalshift geachtet werden. Primaere pulmonale Tumoren zaehlen zu den Raritaeten. Haeufiger sind Sekundaerblastome

  4. Chest trauma in children: current imaging guidelines and techniques.

    LENUS (Irish Health Repository)

    Moore, Michael A

    2011-09-01

    Given the heterogeneous nature of pediatric chest trauma, the optimal imaging approach is tailored to the specific patient. Chest radiography remains the most important imaging modality for initial triage. The decision to perform a chest computed tomography scan should be based on the nature of the trauma, the child\\'s clinical condition, and the initial radiographic findings, taking the age-related pretest probabilities of serious injury into account. The principles of as low as reasonably achievable and Image Gently should be followed. The epidemiology and pathophysiology, imaging techniques, characteristic findings, and evidence-based algorithms for pediatric chest trauma are discussed.

  5. National data analysis of general radiography projection method in medical imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jung Su; Seo, Deok Nam; Choi, In Seok [Dept. of Bio-Convergence Engineering, Korea University Graduate School, Seoul (Korea, Republic of); and others

    2014-09-15

    According to database of medical institutions of health insurance review and assessment service in 2013, 1,118 hospitals and clinics have department of radiology in Korea. And there are CT, fluoroscopic and general radiographic equipment in those hospitals. Above all, general radiographic equipment is the most commonly used in the radiology department. And most of the general radiographic equipment are changing the digital radiography system from the film-screen types of the radiography system nowadays. However, most of the digital radiography department are used the film-screen types of the radiography system. Therefore, in this study, we confirmed present conditions of technical items for general radiography used in hospital and research on general radiographic techniques in domestic medical institutions. We analyzed 26 radiography projection method including chest, skull, spine and pelvis which are generally used in the radiography department.

  6. New computed radiography processing condition for whole-spine radiography.

    Science.gov (United States)

    Sasagawa, Takeshi; Kunogi, Junichi; Masuyama, Shigeru; Ogihara, Satoshi; Takeuchi, Yosuke; Takeshita, Yujiro; Kamiya, Naokazu; Murakami, Hideki; Tsuchiya, Hiroyuki

    2011-12-06

    Computed radiography (CR) has many advantages compared with conventional radiographs, especially in image processing. Although CR is being used in chest radiography and mammography, it has not been applied to spine imaging. The purposes of this study were to formulate a set of new CR processing parameters and to test whether the resultant whole-spine radiographs visualized the spine more clearly than conventional images. This study included 29 patients who underwent whole-spine radiographs. We used 3 image processing methods to improve the clarity of whole-spine radiographs: gradation processing, dynamic range control processing, and multi-objective frequency processing. Radiograph definition was evaluated using vertebrae sampled from each region of the whole spine, specifically C4, C7, T8, T12, and L3; evaluation of the lateral view also included the sacral spine and femoral head. Image definition was assessed using a 3-point grading system. The conventional and processed CR images (both frontal and lateral views) were evaluated by 5 spine surgeons. In all spinal regions on both frontal and lateral views, the processed images showed statistically significantly better clarity than the corresponding conventional images, especially at T12, L3, the sacral spine, and the femoral head on the lateral view. Our set of new CR processing parameters can improve the clarity of whole-spine radiographs compared with conventional images. The greatest advantage of image processing was that it enabled clear depiction of the thoracolumbar junction, lumbar vertebrae, sacrum, and femoral head in the lateral view.

  7. Chest Pain

    Directory of Open Access Journals (Sweden)

    Samad Shams-Vahdati

    2014-03-01

    Full Text Available Introduction: Acute chest pain is an important and frequently occurring symptom in patients. Chest pain is often a sign of ischemic heart disease. Associated findings of electrocardiograph (ECG are rather heterogeneous, and traditional cardiac biomarkers such as Creatine Kinase-MB (CK-MB suffer from low cardiac specificity and sensitivity. In this study cost effectiveness of cardiac biomarkers single quantitative measurement was examined.Methods: The present descriptive-analytic study conducted on patients who were asked for troponin I and CK-MB. All patients who referred to Emergency unit of Tabriz Imam Reza educational-medical center during January 2012 to July the 2013 were included in study. All patients included in the study were documented in terms of age, sex, working shift of referring, main complaint of patient, symptoms in referring, ECG findings, and results of troponin I and CK-MB tests.Results: In this study, 2900 patients were studied including 1440 (49.7% males and 1460 (50.3% females. Mean age of patients was 62.91 (SD=14.36. Of all patients 1880 (64.8% of patients referred during 8 a.m. to 8 p.m. and 1020 (35.2% patients were referred during 8 p.m. to 8 a.m. The sensitivity of cardiac biomarkers’ test in diagnosing Acute Coronary Syndrome (ACS disease was calculated as 44.8% and its specificity was 86.6%. For diagnosing Acute Myocardial Infarction (AMI, sensitivity of cardiac biomarkers’ test was 72.2% and its specificity was 86%. None of patients who were finally underwent unstable angina diagnosis showed increase in cardiac enzymes.Conclusion: In conclusion, cardiac biomarkers can be used for screening acute chest pains, also cost effectiveness of cardiac biomarkers, appropriate specificity and sensitivity can guarantee their usefulness in emergency room.

  8. Dose in conventional radiography; Dosis en radiografia convencional

    Energy Technology Data Exchange (ETDEWEB)

    Acuna D, E.; Padilla R, Z. P.; Escareno J, E.; Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Calle Cipres No. 10, Fracc. La Penuela, 98000 Zacatecas (Mexico)

    2011-10-15

    It has been pointed out that medical exposures are the most significant sources of exposure to ionizing radiation for the general population. Inside the medical exposures the most important is the X-ray use for diagnosis, which is by far the largest contribution to the average dose received by the population. From all studies performed in radiology the chest radiography is the most abundant. In an X-ray machine, voltage and current are combined to obtain a good image and a reduce dose, however due to the workload in a radiology service individual dose is not monitored. In order to evaluate the dose due to chest radiography in this work a plate phantom was built according to the ISO recommendations using methylmethacrylate walls and water. The phantom was used in the Imaging department of the Zacatecas General Hospital as a radiology patient asking for a chest study; using thermoluminescent dosimeters, TLD 100 the kerma at the surface entrance was determined. (Author)

  9. Routine radiography does not have a role in the diagnostic evaluation of ambulatory adult febrile neutropenic cancer patients

    NARCIS (Netherlands)

    Nijhuis, CSMO; Gietema, JA; Vellenga, E; Daenen, SMGJ; De Bont, ESJM; Kamps, WA; Groen, HJM; van der Jagt, EJ; van der Graaf, WTA

    2003-01-01

    Cancer patients treated with chemotherapy are susceptible to bacterial infections. When an adult patient presents with febrile neutropenia. standard diagnostic care includes physical examination, laboratory diagnostics, chest X-ray (CXR) and sinus radiography. However, the yield of routine radiograp

  10. Assessment of clinical image quality in feline chest radiography with a needle-image plate (NIP) storage phosphor system. An approach to the evaluation of image quality in neonatal radiography; Untersuchungen zur Qualitaet von Thoraxaufnahmen bei Katzen mit einem auf einer Nadelstruktur basierenden Speicherfoliensystem. Modelluntersuchungen zur Bewertung der Bildqualitaet bei Neugeborenen

    Energy Technology Data Exchange (ETDEWEB)

    Ludewig, E.; Bosch, B.; Gaebler, K.; Succow, D.; Werrmann, A. [Klinik fuer Kleintiere, Univ. Leipzig (Germany); Hirsch, W.; Sorge, I. [Abt. Paediatrische Radiologie, Univ. Leipzig (Germany); Gosch, D. [Klinik und Poliklinik fuer Diagnostische und Interventionelle Radiologie, Univ. Leipzig (Germany)

    2010-02-15

    Purpose: Is the image quality of thoracic radiographs of cats obtained with a needle-based storage phosphor (NIP) system superior to conventional (PIP) storage phosphor radiography? Is it possible to decrease the mAs by 50% with the NIP system without significant loss of information? Materials and Methods: From each of the 20 animals, three lateral radiographs were acquired. The assessment of the exposure level was based on the generated IgM-values. Images were acquired 1. with the NIP system and exposure settings equivalent to an IgM of 1.9, 2. with the PIP system and identical settings, and 3. with the NIP system and 50% of the mAs. Six blinded readers used a 5-step scale to assess the reproducibility of five anatomical structures and image noise sensation. Data were analysed using Visual Grading Characteristics Analysis (VGC). Results: While applying identical exposure values the NIP system for all features revealed superior ratings to those of the PIP system (AUC{sub VGC} values ranged from 0.81 for ''cardiac silhouette'' to 0.92 for ''trachea''). Even when reducing mAs by 50% in the NIP images all features were rated better compared with the PIP images and original settings (AUC{sub VGC} values ranged from 0.60 for ''cardiac silhouette'' to 0.74 for ''trachea'' and ''caudal thoracic field''). Conclusion: The NIP system demonstrates clearly better image quality compared to the reference PIP system. A dose reduction of 50% seems to be possible without relevant detraction from image quality. The results obtained in the animal model are valid for simulating conditions in neonatal radiological practise. (orig.)

  11. Computer-aided detection of small pulmonary nodules in chest radiographs: an observer study.

    NARCIS (Netherlands)

    Boo, D.W. De; Uffmann, M.; Weber, M.; Bipat, S.; Boorsma, E.F.; Scheerder, M.J.; Freling, N.J.; Schaefer-Prokop, C.M.

    2011-01-01

    RATIONALE AND OBJECTIVES: To evaluate the impact of computer-aided detection (CAD, IQQA-Chest; EDDA Technology, Princeton Junction, NJ) used as second reader on the detection of small pulmonary nodules in chest radiography (CXR). MATERIALS AND METHODS: A total of 113 patients (mean age 62 years) wit

  12. Chest radiation - discharge

    Science.gov (United States)

    Radiation - chest - discharge; Cancer - chest radiation; Lymphoma - chest radiation ... When you have radiation treatment for cancer, your body goes through changes. About 2 weeks after your first treatment: It may be hard ...

  13. MRI of the Chest

    Medline Plus

    Full Text Available ... chest. assess disorders of the chest bones (vertebrae, ribs and sternum) and chest wall soft tissue (muscles ... from the contrast material, including nausea, headache and pain at the site of injection. Similarly, patients are ...

  14. MRI of the Chest

    Medline Plus

    Full Text Available ... chest. assess disorders of the chest bones (vertebrae, ribs and sternum) and chest wall soft tissue (muscles and fat). assess for pericardial (thin sac around the heart) disease. characterize mediastinal or pleural lesions seen by ...

  15. MRI of the Chest

    Medline Plus

    Full Text Available ... MRI of the Chest? What is MRI of the Chest? Magnetic resonance imaging (MRI) is a noninvasive ... of page What are some common uses of the procedure? MR imaging of the chest is performed ...

  16. Chest X Ray?

    Science.gov (United States)

    ... this page from the NHLBI on Twitter. Chest X Ray A chest x ray is a fast and painless imaging test ... tissue scarring, called fibrosis. Doctors may use chest x rays to see how well certain treatments are ...

  17. MRI of the Chest

    Medline Plus

    Full Text Available ... MRI of the Chest? What is MRI of the Chest? Magnetic resonance imaging (MRI) is a noninvasive ... of page What are some common uses of the procedure? MR imaging of the chest is performed ...

  18. MRI of the Chest

    Medline Plus

    Full Text Available ... News Physician Resources Professions Site Index A-Z Magnetic Resonance Imaging (MRI) - Chest Magnetic resonance imaging (MRI) of the chest ... limitations of MRI of the Chest? What is MRI of the Chest? Magnetic resonance imaging (MRI) is ...

  19. WE-E-18A-02: Enhancement of Lung Tumor Visibility by Dual-Energy X-Ray Imaging in An Anthropomorphic Chest Phantom Study

    Energy Technology Data Exchange (ETDEWEB)

    Menten, MJ; Fast, MF; Nill, S; Oelfke, U [The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London (United Kingdom)

    2014-06-15

    Purpose: Intrafractional lung tumor motion during radiotherapy can be compensated for by tracking the tumor position using x-ray imaging and adapting the treatment in real-time. However, locating the tumor with an automated template-matching algorithm is often challenging if the tumor is obscured by ribs. This study investigates the feasibility of creating dual-energy (DE) images of the chest with increased tumor visibility on an Elekta XVI system. Methods: An anthropomorphic chest phantom was imaged at two different energies. Low-energy images were obtained at 80 kVp (0.8 mAs); high-energy images at 129 kVp (0.6 mAs, additional 1.26 mm tin filter). A Geant4 Monte-Carlo framework was developed allowing simulation of the x-ray tube, flat-panel detector and phantom in order to optimize the beam energies, filtration and the weighting factor used to subtract the individual images into a synthetic DE image. The weighting factor was selected to minimize the visibility of bones while maintaining a sufficient tumor visibility. We scored the bone visibility as the contrast of tumor (with bone) to tumor (without bone), and similarly of lung tissue (with bone) to lung tissue (without bone). Tumor visibility was quantified as the contrast between tumor and lung tissue (both without bone). Results: In the experimentally obtained DE image the bone visibility was reduced by 79.2% in tumor and by 96.8% in lung tissue while the overall tumor visibility only decreased by 69.5%. The Monte-Carlo simulation yielded similar results reducing the scores by 90.0%, 85.3% and only 71.9%, respectively. Conclusion: This work demonstrates the feasibility of DE imaging to enhance lung tumor detectability. In the future, we hope to further refine the Monte-Carlo simulation to more accurately predict the weighting factors which would aid real-time implementation. Furthermore, we plan to use the Monte-Carlo framework to simulate DE images of actual lung tumors. The authors would like to thank Paul

  20. Radiography at CERN

    CERN Document Server

    HSE Unit

    2014-01-01

    What is industrial radiography? It is a non-destructive method with a wide variety of applications, such as inspecting the quality of a weld. It uses high-energy radioactive sources or an X-ray generator.   Is this inspection technique used at CERN? Yes, it is widely used at CERN by the EN-MME Group, which outsources the work to one or more companies, depending on the workload. Is it possible to carry out radiography anywhere at CERN? Yes, it is possible to carry out radiography in any building/accelerator/experiment area at CERN (including in areas which are not normally subject to radiological hazards). When is radiography carried out? It normally takes place outside of working hours (7 p.m. to 6 a.m.). How will I know if radiography is taking place in my building? If this activity is planned in a CERN building, notices will be affixed to all of its main entrance doors at least 24 hours in advance. What are the risks? There is a risk of exposure to very high levels of radiation, dep...

  1. Advances in digital chest radiography: impact on reader performance

    NARCIS (Netherlands)

    De Boo, D.W.

    2012-01-01

    Digitalisering binnen de radiologie heeft de nodige verbeteringen opgeleverd, onder andere voor de longfoto. Vroege stadia van longkanker en kleine uitzaaiingen naar de longen worden geregeld gemist op scans, maar computerprogramma’s kunnen deze gemiste afwijkingen soms wel detecteren. De programma’

  2. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... the limitations of Bone X-ray (Radiography)? What is Bone X-ray (Radiography)? An x-ray (radiograph) ... diagnosis and disease management. top of page How is the procedure performed? The technologist, an individual specially ...

  3. Diagnosis and Treatment of Chest Injury and Emergency Diseases of Chest Organs

    Directory of Open Access Journals (Sweden)

    A. M. Khadjibaev

    2016-01-01

    Full Text Available Goal of research: to evaluate efficiency of videothoracoscopy in diagnosis and treatment of patients with injuries and emergency diseases ща chest organs.Material and methods: Study wasbased on treatment results analysis of 2111 patients with injuries and chest organs emergency diseases, who were treated at Republican Research Centre of Emergency Medicine in 2001-2014. Chest trauma made up 1396 (66,1% victims. There were 477 (22,6% patients with spontaneous pneumothorax. At the stages of initial diagnosis, the radiologic evaluations, CT investigations and videothoracoscopies were performed. In chest trauma patients the videothoracoscopy underwent in 844 cases, in spontaneous pneu#mothorax this method was employed in 290 patients. Complicated forms of lung echinococcosis were observed in 238 (11,3% patients and complicated forms of lung echinococcosis were evident in 72 patients.Results. Videothoracoscopy and video-assisted interventions allowed to eliminate lungs and pleura pathology in 1206 (57,1% patients, whereas the traditional methods were effective only in 905 cases (42,9%.Conclusions. Investigation methods such as multiplanar radioscopy, radiography, chest CT and videothora-coscopy must be included into algorithm of diagnosis and surgical treatment of chest injuries and emergency diseases of chest organs. At chest trauma the videothoracoscopy allows to avoid broad thoracotomy from 9,4% to 4,7% of cases, to reduce the frequency of repeated interventions from 17,4% to 0,5% and diminish a number of early postsurgery complications from 25,4% to 10,9%. Videothoracoscopy of chest traumas allows to reduce frequency of repeated interventions from 19,8 to 1,7%.

  4. Real-time radiography

    Energy Technology Data Exchange (ETDEWEB)

    Bossi, R.H.; Oien, C.T.

    1981-02-26

    Real-time radiography is used for imaging both dynamic events and static objects. Fluorescent screens play an important role in converting radiation to light, which is then observed directly or intensified and detected. The radiographic parameters for real-time radiography are similar to conventional film radiography with special emphasis on statistics and magnification. Direct-viewing fluoroscopy uses the human eye as a detector of fluorescent screen light or the light from an intensifier. Remote-viewing systems replace the human observer with a television camera. The remote-viewing systems have many advantages over the direct-viewing conditions such as safety, image enhancement, and the capability to produce permanent records. This report reviews real-time imaging system parameters and components.

  5. Clinical evaluation of digital angiographic system equipped with the Safire' flat-panel detector of a direct conversion type

    Energy Technology Data Exchange (ETDEWEB)

    Miura, Yoshiaki; Miura, Yusuke; Goto, Keiichi [Shimadzu Corporation, Medical Systems Division, Research and Development, Kyoto (JP)] [and others

    2003-06-01

    This report presents a report on clinical evaluation of our newly developed flat-panel X-ray detector of a direct conversion type, designed to provide images of a resolution higher than, or at least equal to, that ensured by X-ray photographic films, in clinical digital X-ray cinematography. This new detector was named 'Safire' the acronym of 'Shimadzu advanced flat imaging receptor', emphasizing its high technological level, such as the capability to ensure high quality of images. The clinical evaluation of Shimadzu DIGITEX Premier digital angiography system, equipped with this new flat-panel X-ray detector of a direct conversion type, has been started in March, 2003, at the Kokura Memorial Hospital in Kyushu, Japan. (author)

  6. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... Resources Professions Site Index A-Z X-ray (Radiography) - Bone Bone x-ray uses a very small ... X-ray (Radiography)? What is Bone X-ray (Radiography)? An x-ray (radiograph) is a noninvasive medical ...

  7. Dose audit for patients undergoing two common radiography examinations with digital radiology systems.

    Science.gov (United States)

    İnal, Tolga; Ataç, Gökçe

    2014-01-01

    We aimed to determine the radiation doses delivered to patients undergoing general examinations using computed or digital radiography systems in Turkey. Radiographs of 20 patients undergoing posteroanterior chest X-ray and of 20 patients undergoing anteroposterior kidney-ureter-bladder radiography were evaluated in five X-ray rooms at four local hospitals in the Ankara region. Currently, almost all radiology departments in Turkey have switched from conventional radiography systems to computed radiography or digital radiography systems. Patient dose was measured for both systems. The results were compared with published diagnostic reference levels (DRLs) from the European Union and International Atomic Energy Agency. The average entrance surface doses (ESDs) for chest examinations exceeded established international DRLs at two of the X-ray rooms in a hospital with computed radiography. All of the other ESD measurements were approximately equal to or below the DRLs for both examinations in all of the remaining hospitals. Improper adjustment of the exposure parameters, uncalibrated automatic exposure control systems, and failure of the technologists to choose exposure parameters properly were problems we noticed during the study. This study is an initial attempt at establishing local DRL values for digital radiography systems, and will provide a benchmark so that the authorities can establish reference dose levels for diagnostic radiology in Turkey.

  8. Chest x-ray

    Science.gov (United States)

    ... of the following symptoms: A persistent cough Chest pain from a chest injury (with a possible rib fracture or lung complication) or from heart problems Coughing up blood Difficulty breathing Fever It ...

  9. MRI of the Chest

    Medline Plus

    Full Text Available ... chest. It is primarily used to assess abnormal masses such as cancer and determine the size, extent ... of the chest is performed to: assess abnormal masses, including cancer of the lungs or other tissues, ...

  10. MRI of the Chest

    Medline Plus

    Full Text Available ... the limitations of MRI of the Chest? What is MRI of the Chest? Magnetic resonance imaging (MRI) ... ray, CT and ultrasound. top of page How is the procedure performed? MRI examinations may be performed ...

  11. Chest X-Ray

    Medline Plus

    Full Text Available ... chest x-ray is used to evaluate the lungs, heart and chest wall and may be used ... diagnose and monitor treatment for a variety of lung conditions such as pneumonia, emphysema and cancer. A ...

  12. Chest X-Ray

    Medline Plus

    Full Text Available ... breath, persistent cough, fever, chest pain or injury. It may also be useful to help diagnose and ... have some concerns about chest x-rays. However, it’s important to consider the likelihood of benefit to ...

  13. MRI of the Chest

    Medline Plus

    Full Text Available ... to assess the anatomy and function of the heart and its blood flow. Tell your doctor about ... chest cavity, including the mediastinum , chest wall, pleura, heart and vessels, from almost any angle. MRI also ...

  14. Chest X-Ray

    Medline Plus

    Full Text Available ... breath, persistent cough, fever, chest pain or injury. It may also be useful to help diagnose and ... have some concerns about chest x-rays. However, it’s important to consider the likelihood of benefit to ...

  15. Management of flail chest.

    OpenAIRE

    Miller, H A; Taylor, G.A.; Harrison, A. W.; Maggisano, R.; Hanna, S.; de Lacy, J. L.; Shulman, H.

    1983-01-01

    This paper compares the management of two groups of patients with flail chest. The 25 patients in group 1 had a flail chest without other significant injuries or shock, whereas the 57 in group 2 had a flail chest with multiple injuries, shock or both. The group 1 patients were treated with repeated multiple intercostal nerve blocks or high segmental epidural analgesia, oxygen, intensive chest physiotherapy, fluid restriction, furosemide diuretics, methylprednisolone sodium succinate and collo...

  16. Artifacts in digital radiography

    Energy Technology Data Exchange (ETDEWEB)

    Min, Jung Whan [Dept. of Radiological Technology, Shin Gu University, Sungnam (Korea, Republic of); Kim, Jung Min [Dept. of Radiological Technology, Korea University, Seoul (Korea, Republic of); Jeong, Hoi Woun [Dept. of Radiological Technology, Beakseok Culture University, Cheonan (Korea, Republic of)

    2015-12-15

    Digital Radiography is a big part of diagnostic radiology. Because uncorrected digital radiography image supported false effect of Patient’s health care. We must be manage the correct digital radiography image. Thus, the artifact images can have effect to make a wrong diagnosis. We report types of occurrence by analyzing the artifacts that occurs in digital radiography system. We had collected the artifacts occurred in digital radiography system of general hospital from 2007 to 2014. The collected data had analyzed and then had categorize as the occurred causes. The artifacts could be categorized by hardware artifacts, software artifacts, operating errors, system artifacts, and others. Hardware artifact from a Ghost artifact that is caused by lag effect occurred most frequently. The others cases are the artifacts caused by RF noise and foreign body in equipments. Software artifacts are many different types of reasons. The uncorrected processing artifacts and the image processing error artifacts occurred most frequently. Exposure data recognize (EDR) error artifacts, the processing error of commissural line, and etc., the software artifacts were caused by various reasons. Operating artifacts were caused when the user did not have the full understanding of the digital medical image system. System artifacts had appeared the error due to DICOM header information and the compression algorithm. The obvious artifacts should be re-examined, and it could result in increasing the exposure dose of the patient. The unclear artifact leads to a wrong diagnosis and added examination. The ability to correctly determine artifact are required. We have to reduce the artifact occurrences by understanding its characteristic and providing sustainable education as well as the maintenance of the equipments.

  17. American College of Chest Physicians

    Science.gov (United States)

    ... Master Fellows Staff & Contact Us CHEST Newsroom Staff Job Opportunities at CHEST Contact Us Industry Support Industry Support ... of Global Governors Master Fellows CHEST Newsroom Staff Job Opportunities at CHEST Contact Us Industry Support Industry Advisory ...

  18. Pediatric chest CT after trauma: impact on surgical and clinical management

    Energy Technology Data Exchange (ETDEWEB)

    Patel, Rina P. [Vanderbilt University School of Medicine, Nashville, TN (United States); Hernanz-Schulman, Marta; Hilmes, Melissa A.; Kan, J.H. [Vanderbilt University, Department of Radiology and Radiological Sciences, Vanderbilt Children' s Hospital, Nashville, TN (United States); Yu, Chang [Vanderbilt University, Department of Biostatistics, Nashville, TN (United States); Ray, Jackie [Vanderbilt University, Department of Pediatric Surgery, Vanderbilt Children' s Hospital, Nashville, TN (United States)

    2010-07-15

    Chest CT after pediatric trauma is frequently performed but its clinical impact, particularly with respect to surgical intervention, has not been adequately evaluated. To assess the impact of chest CT compared with chest radiography on pediatric trauma management. Two hundred thirty-five consecutive pediatric trauma patients who had both chest CT and radiography were identified. Images were reviewed and findings were categorized and correlated with subsequent chest interventions, blinded to final outcome and management. Of the 235 children, 38.3% (90/235) had an abnormal chest radiograph and 63.8% (150/235) had an abnormal chest CT (P < 0.0001). Chest interventions followed in 4.7% (11/235); of these, the findings could be made 1 cm above the dome of the liver in 91% (10/11). Findings requiring chest intervention included pneumothorax (PTX) and vertebral fractures. PTX was found on 2.1% (5/235) of chest radiographs and 20.0% (47/235) of chest CTs (P < 0.0001); 1.7% (4/235) of the children received a chest tube for PTX, 0.85% (2/235) seen on chest CT only. Vertebral fractures were present in 3.8% of the children (9/235) and 66.7% (6/9) of those cases were treated with spinal fusion or brace. There were no instances of mediastinal vascular injury. Most intrathoracic findings requiring surgical management in our population were identified in the lower chest and would be included in routine abdominopelvic CT exams; this information needs to be taken into consideration in the diagnostic algorithm of pediatric trauma patients. (orig.)

  19. Use of Chest Computed Tomography in Stable Patients with Blunt Thoracic Trauma: Clinical and Forensic Perspective

    Directory of Open Access Journals (Sweden)

    Makbule Ergin

    2011-01-01

    fractures were the most common injury. Thorax computed tomography was significantly superior to chest radiography in detecting pneumothorax , hemothorax and lung contusion. Eightyone life threatening lesions were detected and 50 (61%; pneumothorax 13, hemothorax 24, lung contusion 9,and pneumomediastinum 4 of these lesions could not be detected with plain chest radiography. The clinical management [in 15 patients (30%], and the forensic assesment was changed [in 14 (28%] patients were changed.  Conclusion:We concluded that using Computed Tomography of the thorax in thoracic travmas prive meticulous assesment in management of patients and forens icissues.

  20. Quantitative film radiography

    Energy Technology Data Exchange (ETDEWEB)

    Devine, G.; Dobie, D.; Fugina, J.; Hernandez, J.; Logan, C.; Mohr, P.; Moss, R.; Schumacher, B.; Updike, E.; Weirup, D.

    1991-02-26

    We have developed a system of quantitative radiography in order to produce quantitative images displaying homogeneity of parts. The materials that we characterize are synthetic composites and may contain important subtle density variations not discernible by examining a raw film x-radiograph. In order to quantitatively interpret film radiographs, it is necessary to digitize, interpret, and display the images. Our integrated system of quantitative radiography displays accurate, high-resolution pseudo-color images in units of density. We characterize approximately 10,000 parts per year in hundreds of different configurations and compositions with this system. This report discusses: the method; film processor monitoring and control; verifying film and processor performance; and correction of scatter effects.

  1. Effect of comfort pads and incubator design on neonatal radiography

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Xia; Baad, Michael; Reiser, Ingrid; Feinstein, Kate A.; Lu, Zhengfeng [University of Chicago Medicine, Department of Radiology, Chicago, IL (United States)

    2016-01-15

    There has been increasing interest in patient dose reduction in neonatal intensive care units. Removing comfort pads for radiography has been identified as a potential means to decrease patient dose. To assess the effect of comfort pads and support trays on detector entrance exposure (DEE) and image quality for neonatal radiography, and its implication for patient dose. Comfort pads and support trays from three incubator and warmer systems were examined. The attenuation of the primary beam by these structures was measured using a narrow beam geometry. Their effect on DEE and image quality was then assessed using typical neonatal chest radiography techniques with three configurations: (1) both the comfort pad and support included in the beam, (2) only the support tray included and (3) both the comfort pad and support tray removed. Comfort pads and support trays were found to attenuate the primary beam by 6-15%. Eliminating these structures from the X-ray beam's path was found to increase the detector entrance exposure by 28-36% and increase contrast-to-noise ratio by more than 21%, suggesting room for patient dose reduction when the same image quality is maintained. Comfort pads and tray support devices can have a considerable effect on DEE and image quality, with large variations among different incubator designs. Positioning the image detector directly underneath neonatal patients for radiography is a potential means for patient dose reduction. However, such benefit should be weighed against the risks of moving the patient. (orig.)

  2. Radiography with polarised neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Schulz, Michael L.

    2010-08-20

    In this thesis I present a new technique for the spatially resolved investigation of the magnetic properties of bulk samples. Standard one dimensional neutron depolarisation analysis is combined with neutron radiography to a method we call Neutron Depolarisation Imaging (NDI). The experimental setup which was installed at the neutron radiography beam line ANTARES at FRM II consists of a double crystal monochromator, neutron polariser, spin flipper, polarisation analyser and a position sensitive CCD detector. A comprehensive discussion of the requirements for these components is given and the limitations of the method are shown. The maximum spatial resolution which can be achieved with a neutron radiography setup is determined by the collimation of the neutron beam and the distance between sample and detector. Different types of polarisers have been tested and their advantages and disadvantages are discussed. A double crystal monochromator and a new type of polariser employing polarising neutron supermirrors based on the principle of an optical periscope were developed and tested during this work. Furthermore, NDI measurements on various samples of the weakly ferromagnetic materials Pd{sub 1-x}Ni{sub x} and Ni{sub 3}Al are presented. Neutron depolarisation radiography and tomography measurements were conducted with a spatial resolution as high as 0.3 mm on Pd{sub 1-x}Ni{sub x} and Ni{sub 3}Al samples. The feasibility of NDI experiments under hydrostatic pressures up to 10 kbar was shown on a sample of Ni{sub 3}Al using a modified Cu:Be clamp cell. A decrease of the ordering temperature by 2 K under hydrostatic pressure was determined from the NDI measurements and shows the potential of the method for further high pressure experiments. Additionally a method was developed which in principle allows to obtain the intrinsic dependence of the ordering temperature T{sub C} on the ordered moment Ms from NDI measurements on inhomogeneous samples containing regions with

  3. Chest pain associated with moderator band pacing.

    Science.gov (United States)

    Goli, Anil K; Kaszala, Karoly; Osman, Mohammed N; Lucke, John; Carrillo, Roger

    2014-10-01

    A 65-year-old man was evaluated for chronic chest pain that had been present for 8 years after placement of a dual-chamber implantable cardioverter-defibrillator to treat inducible ventricular tachycardia. Previous coronary angiography had revealed nonobstructive coronary artery disease and a left ventricular ejection fraction of 0.45 to 0.50, consistent with mild idiopathic nonischemic cardiomyopathy. Evaluation with chest radiography and transthoracic echocardiography showed the implantable cardioverter-defibrillator lead to be embedded within the right ventricle at the moderator band, which had mild calcification. Treatment included extraction of the dual-coil lead and placement of a new single-coil right ventricular lead at the mid septum. The patient had complete relief of symptoms after the procedure. This case shows that chest pain can be associated with the placement of a right ventricular implantable cardioverter-defibrillator lead in the moderator band and that symptomatic relief can occur after percutaneous lead extraction and the implantation of a new right ventricular lead to the mid septal region.

  4. Central venous cannulation: are routine chest radiographs necessary after B-mode and colour Doppler sonography check?

    Energy Technology Data Exchange (ETDEWEB)

    Lanza, Cecilia; Fabrizzi, Giancarlo [Pediatric Radiology Department-Presidio Salesi, Azienda Ospedaliero-Universitaria Ospedali Riuniti, Ancona (Italy); Russo, Marco [Ospedale Civile Engles Profili, Servizio di Radiologia, Ancona (Italy)

    2006-12-15

    After the insertion of a central venous catheter, a chest radiograph is usually obtained to ensure correct positioning of the catheter tip. To determine in a paediatric population whether B-mode and colour Doppler sonography after central venous access is useful to evaluate catheter position, thus obviating the need for a postprocedural radiograph. A prospective study of 107 consecutive central venous access procedures placed in a paediatric intensive care unit was performed. At the end of the procedure, B-mode and colour Doppler sonography were used to assess catheter position and check for complications. A postprocedural chest radiograph was obtained in all patients. In 96 patients postprocedural B-mode and colour Doppler sonography showed colour Doppler signals within the vena cava. Among the 11 patients predicted to have a potential complication, there was one pneumothorax and ten malpositions. Chest radiography showed a total of 13 complications - 1 pneumothorax and 12 malpositions. The concordance between colour Doppler sonography and chest radiography was 98.1% in the detection of catheter position; sonography had a sensitivity of 84.6% and a specificity of 100%. The close concordance between B-mode and colour Doppler sonography and chest radiography justifies the more frequent use of sonography to evaluate catheter position because ionizing radiation is eliminated. Chest radiography may then be performed only when there is suspected inappropriate catheter tip position after sonography. (orig.)

  5. Scatter in cargo radiography.

    Science.gov (United States)

    Miller, Erin A; Caggiano, Joseph A; Runkle, Robert C; White, Timothy A; Bevill, Aaron M

    2011-03-01

    As a complement to passive detection systems, radiographic inspection of cargo is an increasingly important tool for homeland security because it has the potential to detect highly attenuating objects associated with special nuclear material or surrounding shielding, in addition to screening for items such as drugs or contraband. Radiographic detection of such threat objects relies on high image contrast between regions of different density and atomic number (Z). Threat detection is affected by scatter of the interrogating beam in the cargo, the radiographic system itself, and the surrounding environment, which degrades image contrast. Here, we estimate the extent to which scatter plays a role in radiographic imaging of cargo containers. Stochastic transport simulations were performed to determine the details of the radiography equipment and surrounding environment, which are important in reproducing measured data and to investigate scatter magnitudes for typical cargo. We find that scatter plays a stronger role in cargo radiography than in typical medical imaging scenarios, even for low-density cargo, with scatter-to-primary ratios ranging from 0.14 for very low density cargo, to between 0.20 and 0.40 for typical cargo, and higher yet for dense cargo.

  6. Fifty years of computer analysis in chest imaging: rule-based, machine learning, deep learning

    NARCIS (Netherlands)

    Ginneken, B. van

    2017-01-01

    Half a century ago, the term "computer-aided diagnosis" (CAD) was introduced in the scientific literature. Pulmonary imaging, with chest radiography and computed tomography, has always been one of the focus areas in this field. In this study, I describe how machine learning became the dominant techn

  7. Chest X-ray patterns of pulmonary multidrug-resistant tuberculosis in ...

    African Journals Online (AJOL)

    2016-03-18

    Mar 18, 2016 ... 1Department of Radiology,. University of ... rifampicin, is a particular area of public health concern in South Africa, where the estimated. MDR-TB .... Frontal chest X-rays were acquired using digital radiography. (with Kodak ...

  8. Fifty years of computer analysis in chest imaging: rule-based, machine learning, deep learning

    NARCIS (Netherlands)

    Ginneken, B. van

    2017-01-01

    Half a century ago, the term "computer-aided diagnosis" (CAD) was introduced in the scientific literature. Pulmonary imaging, with chest radiography and computed tomography, has always been one of the focus areas in this field. In this study, I describe how machine learning became the dominant

  9. Multidetector computed tomography-spectrum of blunt chest wall and lung injuries in polytraumatized patients

    Energy Technology Data Exchange (ETDEWEB)

    Peters, S., E-mail: soeren.peters@rub.d [Department of Radiology and Nuclear Medicine, BG Universitaetsklinikum Bergmannsheil, Buerkle-de-la-Camp-Platz 1, 44789 Bochum (Germany); Nicolas, V.; Heyer, C.M. [Department of Radiology and Nuclear Medicine, BG Universitaetsklinikum Bergmannsheil, Buerkle-de-la-Camp-Platz 1, 44789 Bochum (Germany)

    2010-04-15

    Accidental injuries are the leading cause of death in the 15 to 44-year-old age group. Blunt chest trauma is often encountered in these patients and is associated with a mortality of up to 25%. Although conventional radiography still plays an important role in the initial emergency room setting, for follow-up in the intensive care unit, multidetector computed tomography has established itself as the standard imaging method for the evaluation of chest trauma patients. The following review presents salient radiological findings of the chest wall and shoulder girdle, thoracic spine, pleural space, and lung in polytraumatized patients.

  10. Chest computed tomography

    DEFF Research Database (Denmark)

    Loeve, Martine; Krestin, Gabriel P.; Rosenfeld, Margaret

    2013-01-01

    Clinical trials for the treatment of cystic fibrosis (CF) lung disease are important to test and optimize new therapeutic interventions. To evaluate the effect of these interventions, sensitive and accurate outcome measures are needed. The most commonly used endpoints are spirometric variables...... are not suitable to study CF lung disease in young children. Chest computed tomography (CT) holds great promise for use as a sensitive surrogate endpoint in CF. A large body of evidence has been produced to validate the use of chest CT as primary endpoint to study CF lung disease. However, before chest CT can...

  11. Posterior diaphragmatic defect detected on chest CT: the incidence according to age and the lateral chest radiographic appearances

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Son Youl; Choi, Yo Won; Jeon, Seok Chol; Heo, Jeong Nam; Park, Choong Ki [College of Medicine, Hanyang University, Seoul (Korea, Republic of)

    2007-03-15

    We wanted to investigate the incidence of posterior diaphragmatic defect on chest CT in various age groups and its lateral chest radiographic appearances. The chest CT scans of 78 patients of various ages with posterior diaphragmatic defect were selected among 1,991 patients, and they were analyzed for the incidence of defect in various age groups, the defect location and the herniated contents. Their lateral chest radiographs were analyzed for the shape of the posterior diaphragm and the posterior costophrenic sulcus. The patients' ages ranged from 34 to 87 with the tendency of a higher incidence in the older patients. The defect most frequently involved the medial two thirds (n = 49, 50.4%) and middle one third (n = 36, 37%) of the posterior diaphragm. The retroperitoneal fat was herniated into the thorax through the defect in all patients, and sometimes with the kidney (n = 8). Lateral chest radiography showed a normal diaphragmatic contour (n = 51, 49.5%), blunting of the posterior costophrenic sulcus (n = 41, 39.8%), focal humping of the posterior diaphragm (n = 7, 6.8%), or upward convexity (n = 4, 3.9%) of the posterior costophrenic sulcus on the affected side. The posterior diaphragmatic defect discovered in asymptomatic patients who are without a history of peridiaphragmatic disease is most likely acquired, and this malady increases in incidence according to age. An abnormal contour of the posterior diaphragm or the costophrenic sulcus on a lateral chest radiograph may be a finding of posterior diaphragmatic defect.

  12. Radiography students' clinical learning styles.

    Science.gov (United States)

    Ward, Patti; Makela, Carole

    2010-01-01

    To examine the common learning styles of radiography students during clinical practice. Descriptive research methodology, using a single self-report questionnaire, helped to identify common learning styles of radiography students during clinical practice. The results indicated that 3 learning styles predominate among radiography students during clinical practice: task oriented, purposeful and tentative. Insight into clinical practice learning styles can help students understand how they learn and allow them to recognize ways to maximize learning. It also heightens awareness among clinical instructors and technologists of the different learning styles and their relevance to clinical practice education.

  13. Simple X-ray versus ultrasonography examination in blunt chest trauma: effective tools of accurate diagnosis and considerations for rib fractures.

    Science.gov (United States)

    Hwang, Eun Gu; Lee, Yunjung

    2016-12-01

    Simple radiography is the best diagnostic tool for rib fractures caused by chest trauma, but it has some limitations. Thus, other tools are also being used. The aims of this study were to investigate the effectiveness of ultrasonography (US) for identifying rib fractures and to identify influencing factors of its effectiveness. Between October 2003 and August 2007, 201 patients with blunt chest trauma were available to undergo chest radiographic and US examinations for diagnosis of rib fractures. The two modalities were compared in terms of effectiveness based on simple radiographic readings and US examination results. We also investigated the factors that influenced the effectiveness of US examination. Rib fractures were detected on radiography in 69 patients (34.3%) but not in 132 patients. Rib fractures were diagnosed by using US examination in 160 patients (84.6%). Of the 132 patients who showed no rib fractures on radiography, 92 showed rib fractures on US. Among the 69 patients of rib fracture detected on radiography, 33 had additional rib fractures detected on US. Of the patients, 76 (37.8%) had identical radiographic and US results, and 125 (62.2%) had fractures detected on US that were previously undetected on radiography or additional fractures detected on US. Age, duration until US examination, and fracture location were not significant influencing factors. However, in the group without detected fractures on radiography, US showed a more significant effectiveness than in the group with detected fractures on radiography (P=0.003). US examination could detect unnoticed rib fractures on simple radiography. US examination is especially more effective in the group without detected fractures on radiography. More attention should be paid to patients with chest trauma who have no detected fractures on radiography.

  14. MRI of the Chest

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    Full Text Available ... to a CD or uploaded to a digital cloud server. MRI of the chest gives detailed pictures ... artery ( dissection ). See the MRA page for more information. top of page How should I prepare? You ...

  15. MRI of the Chest

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    Full Text Available ... primarily used to assess abnormal masses such as cancer and determine the size, extent and degree of ... chest is performed to: assess abnormal masses, including cancer of the lungs or other tissues, which either ...

  16. MRI of the Chest

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    Full Text Available ... primarily used to assess abnormal masses such as cancer and determine the size, extent and degree of ... chest is performed to: assess abnormal masses, including cancer of the lungs or other tissues, which either ...

  17. Chest X-Ray

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    Full Text Available ... Index A-Z Spotlight October is National Breast Cancer Awareness Month Recently posted: Medical Imaging Costs Magnetoencephalography ( ... of lung conditions such as pneumonia, emphysema and cancer. A chest x-ray requires no special preparation. ...

  18. MRI of the Chest

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    Full Text Available ... or headphones during the exam. MRI scanners are air-conditioned and well-lit. Music may be played ... the limitations of MRI of the Chest? High-quality images are assured only if you are able ...

  19. MRI of the Chest

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    Full Text Available ... a CD or uploaded to a digital cloud server. MRI of the chest gives detailed pictures of ... suggestion into the following text box: Comment: E-mail: Area code: Phone no: Thank you! Do you ...

  20. MRI of the Chest

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    Full Text Available ... for lung abnormalities where Chest CT is a preferred imaging test. MR imaging can assess blood flow ... If you are anxious, confused or in severe pain, you may find it difficult to lie still ...

  1. MRI of the Chest

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    Full Text Available ... the chest uses a powerful magnetic field, radio waves and a computer to produce detailed pictures of ... the body being imaged, send and receive radio waves, producing signals that are detected by the coils. ...

  2. MRI of the Chest

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    Full Text Available ... Us News Physician Resources Professions Site Index A-Z Magnetic Resonance Imaging (MRI) - Chest Magnetic resonance imaging ( ... the child can watch a movie while the scan is being performed. Thus, the child remains motionless ...

  3. MRI of the Chest

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    Full Text Available ... to: assess abnormal masses, including cancer of the lungs or other tissues, which either cannot be assessed ... for differentiating and characterizing soft tissues, except for lung abnormalities where Chest CT is a preferred imaging ...

  4. Chest tube insertion - slideshow

    Science.gov (United States)

    ... presentations/100008.htm Chest tube insertion - series—Normal anatomy To use the sharing features ... pleural space is the space between the inner and outer lining of the lung. It is normally very thin, and lined only ...

  5. MRI of the Chest

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    Full Text Available ... detailed pictures of the structures within the chest. It is primarily used to assess abnormal masses such ... and determine the size, extent and degree of its spread to adjacent structures. It’s also used to ...

  6. Chest tube insertion

    Science.gov (United States)

    ... tube insertion; Insertion of tube into chest; Tube thoracostomy; Pericardial drain ... Kirsch TD, Sax J. Tube thoracostomy. In: Roberts JR, ed. Roberts and ... . 6th ed. Philadelphia, PA: Elsevier Saunders; 2014:chap 10.

  7. MRI of the Chest

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    Full Text Available ... News Physician Resources Professions Site Index A-Z Magnetic Resonance Imaging (MRI) - Chest Magnetic resonance imaging (MRI) of ... Although there is no reason to believe that magnetic resonance imaging harms the fetus, pregnant women usually are ...

  8. MRI of the Chest

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    Full Text Available ... copied to a CD or uploaded to a digital cloud server. MRI of the chest gives detailed ... the technologist if you have medical or electronic devices in your body. These objects may interfere with ...

  9. MRI of the Chest

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    Full Text Available ... heart) and myocardial infarct (scar in the heart muscle due to prior obstruction of blood flow). determine ... ribs and sternum) and chest wall soft tissue (muscles and fat). assess for pericardial (thin sac around ...

  10. MRI of the Chest

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    Full Text Available ... ribs and sternum) and chest wall soft tissue (muscles and fat). assess for pericardial (thin sac around the heart) disease. characterize mediastinal or pleural lesions seen by other ...

  11. MRI of the Chest

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    Full Text Available ... heart) and myocardial infarct (scar in the heart muscle due to prior obstruction of blood flow). determine ... ribs and sternum) and chest wall soft tissue (muscles and fat). assess for pericardial (thin sac around ...

  12. MRI of the Chest

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    Full Text Available ... determine the presence of certain diseases. The images can then be examined on a computer monitor, transmitted ... of the chest cavity (arteries and veins). MRA can also demonstrate an abnormal ballooning out of the ...

  13. MRI of the Chest

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    Full Text Available ... is not harmful, but it may cause some medical devices to malfunction. Most orthopedic implants pose no ... Chest? Magnetic resonance imaging (MRI) is a noninvasive medical test that physicians use to diagnose medical conditions. ...

  14. MRI of the Chest

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    Full Text Available ... of the chest uses a powerful magnetic field, radio waves and a computer to produce detailed pictures ... medical conditions. MRI uses a powerful magnetic field, radio frequency pulses and a computer to produce detailed ...

  15. MRI of the Chest

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    Full Text Available ... detailed pictures of the structures within the chest. It is primarily used to assess abnormal masses such ... and determine the size, extent and degree of its spread to adjacent structures. It’s also used to ...

  16. Neonatal Chest Wall Rhabdomyosarcoma.

    Science.gov (United States)

    Feldman, Michael; Steiner, Zvi; Groisman, Gabriel; Nadir, Erez

    2015-06-01

    An infant was born at term with a huge chest mass diagnosed as rhabdomyosarcoma. Treatment consisted of surgical resection and chemotherapy. We describe this very rare congenital mass and the problematic therapeutic management of such a tumor in a newborn.

  17. Neonatal Chest Wall Rhabdomyosarcoma

    OpenAIRE

    Feldman, Michael; Steiner, Zvi; Groisman, Gabriel; Nadir, Erez

    2015-01-01

    An infant was born at term with a huge chest mass diagnosed as rhabdomyosarcoma. Treatment consisted of surgical resection and chemotherapy. We describe this very rare congenital mass and the problematic therapeutic management of such a tumor in a newborn.

  18. Chest X-Ray

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    Full Text Available ... CT Angiography Video: Myelography Video: CT of the Heart Video: Radioiodine I-131 Therapy Radiology and You ... x-ray is used to evaluate the lungs, heart and chest wall and may be used to ...

  19. MRI of the Chest

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    Full Text Available ... You may resume your usual activities and normal diet immediately after the exam. On very rare occasions, ... Magnetic Resonance Imaging (MRI) Safety MRI Safety During Pregnancy Images related to Magnetic Resonance Imaging (MRI) - Chest ...

  20. Euratom Neutron Radiography Working Group

    DEFF Research Database (Denmark)

    Domanus, Joseph Czeslaw

    1986-01-01

    In 1979 a Neutron Radiography Working Group (NRWG) was constituted within Buratom with the participation of all centers within the European Community at which neutron facilities were available. The main purpose of NRWG was to standardize methods and procedures used in neutron radiography of nuclear...... reactor fuel as well as establish standards for radiographic image quality of neutron radiographs. The NRWG meets once a year in each of the neutron radiography centers to review the progress made and draw plans for the future. Besides, ad-hoc sub-groups or. different topics within the field of neutron...... radiography are constituted. This paper reviews the activities and achievements of the NRWG and its sub-groups....

  1. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... Us News Physician Resources Professions Site Index A-Z X-ray (Radiography) - Bone Bone x-ray uses ... assess trauma patients in emergency departments. A CT scan can image complicated fractures, subtle fractures or dislocations. ...

  2. Abdomen X-Ray (Radiography)

    Science.gov (United States)

    ... Professions Site Index A-Z X-ray (Radiography) - Abdomen Abdominal x-ray uses a very small dose ... to produce pictures of the inside of the abdominal cavity. It is used to evaluate the stomach, liver, ...

  3. Proton Radiography (pRad)

    Data.gov (United States)

    Federal Laboratory Consortium — The proton radiography project has used 800 MeV protons provided by the LANSCE accelerator facility at LANL, to diagnose more than 300 dynamic experiments in support...

  4. Examination of musculoskeletal chest pain

    DEFF Research Database (Denmark)

    Brunse, Mads Hostrup; Stochkendahl, Mette Jensen; Vach, Werner

    2010-01-01

    Chest pain may be caused by joint and muscle dysfunction of the neck and thorax (termed musculoskeletal chest pain). The objectives of this study were (1) to determine inter-observer reliability of the diagnosis 'musculoskeletal chest pain' in patients with acute chest pain of non-cardiac origin...

  5. Chest radiographic manifestations of scrub typhus

    Directory of Open Access Journals (Sweden)

    KPP Abhilash

    2016-01-01

    Full Text Available Background and Rationale: Respiratory system involvement in scrub typhus is seen in 20–72% of patients. In endemic areas, good understanding and familiarity with the various radiologic findings of scrub typhus are essential in identifying pulmonary complications. Materials and Methods: Patients admitted to a tertiary care center with scrub typhus between October 2012 and September 2013 and had a chest X ray done were included in the analysis. Details and radiographic findings were noted and factors associated with abnormal X-rays were analyzed. Results: The study cohort contained 398 patients. Common presenting complaints included fever (100%, generalized myalgia (83%, headache (65%, dyspnea (54%, cough (24.3%, and altered sensorium (14%. Almost half of the patients (49.4% had normal chest radiographs. Common radiological pulmonary abnormalities included pleural effusion (14.6%, acute respiratory distress syndrome (14%, airspace opacity (10.5%, reticulonodular opacities (10.3%, peribronchial thickening (5.8%, and pulmonary edema (2%. Cardiomegaly was noted in 3.5% of patients. Breathlessness, presence of an eschar, platelet counts of 2 mg/dL had the highest odds of having an abnormal chest radiograph. Patients with an abnormal chest X-ray had a higher requirement of noninvasive ventilation (odds ratio [OR]: 13.98; 95% confidence interval CI: 5.89–33.16, invasive ventilation (OR: 18.07; 95% CI: 6.42–50.88, inotropes (OR: 8.76; 95% CI: 4.35–17.62, higher involvement of other organ systems, longer duration of hospital stay (3.18 ± 3 vs. 7.27 ± 5.58 days; P< 0.001, and higher mortality (OR: 4.63; 95% CI: 1.54–13.85. Conclusion: Almost half of the patients with scrub typhus have abnormal chest radiographs. Chest radiography should be included as part of basic evaluation at presentation in patients with scrub typhus, especially in those with breathlessness, eschar, jaundice, and severe thrombocytopenia.

  6. Practical measurement of radiation dose in pediatric radiology: use of the dose-area product on digital fluoroscopy and neonatal chest radiographs; Mesure pratique de l'irradiation en radiopediatrie: utilisation du produit dose surface en fluorographie numerique et pour les radiographies pulmonaires neonatales

    Energy Technology Data Exchange (ETDEWEB)

    Chateil, J.F.; Rouby, C.; Brun, M.; Labessan, C.; Diard, F. [Hopital Pellegrin, Unite de Radiopediatrie A., 33 - Bordeaux (France)

    2004-05-01

    Purpose. Control of radiation dose in pediatric radiology requires knowledge of the reference levels for all examinations. These data are useful for daily quality assessment, but are not perfectly known for some radiographic examinations. The purpose of our study was to evaluate the dose related to voiding cysto-urethrograms (VCUG), upper GI (UGI) and intravenous urography (IVU). Neonatal chest radiographs in the intensive care unit were also evaluated. Material and methods. For examinations with contrast material (478VCUG, 220UGI, 80IVU), the children were divided in groups based on their weight, from 5 to 30 Kg. Measurements were performed using an ionization chamber and expressed with the-dose-area product (DAP). For chest radiographs, a direct measurement of the entrance-skin dose was performed, with secondary calculation of the DAP. Results. For-VCUGs, the DAP ranged between 42.89 cGy.cm{sup 2} and 125.41 cGy.cm{sup 2}. The range was between 76.43, and 150.62 cGy.cm{sup 2} for UGIs and between 49.06 and 83.33 cGy.cm{sup 2} for IVUs. For neonate chest radiographs, DAP calculations were between 0.29 and 0.99 cGy.cm{sup 2}. Conclusion. These values represent our reference doses. They allow continuous monitoring of our radiographic technical parameters and radiographic equipment and help to correct and improve them if necessary. (author)

  7. CHEST PHYSIOTHERAPY FOR INFANTS

    Directory of Open Access Journals (Sweden)

    Preeti S. Christian (M.P.T Cardiopulmonary Conditions

    2014-10-01

    Full Text Available In the normal lung, secretions are removed by Mucociliary activity, normal breathing cycles, and cough. In disease, increased secretion viscosity and volume, dyskinesia of the cilia, and ineffective cough combine to reduce the ability to clear secretions, and may increase exacerbations and infections. Many chest physiotherapy techniques like postural drainage, percussion and vibration are used since many years. These techniques are derived from adult studies but these techniques are quite stressful for the infants as the infant respiratory system is different from the adult respiratory system. Advance chest physiotherapy techniques were developed specifically for infants; in accordance with their physiological characteristics. So this review is to introduce some new chest physiotherapy helpful for newborn infants.

  8. Upper Gastrointestinal (GI) Tract X-Ray (Radiography)

    Science.gov (United States)

    ... Site Index A-Z X-ray (Radiography) - Upper GI Tract Upper gastrointestinal tract radiography or upper GI ... GI) Tract X-ray? What is Upper Gastrointestinal (GI) Tract Radiography? Upper gastrointestinal tract radiography, also called ...

  9. Lower Gastrointestinal (GI) Tract X-Ray (Radiography)

    Science.gov (United States)

    ... Site Index A-Z X-ray (Radiography) - Lower GI Tract Lower gastrointestinal tract radiography or lower GI ... of Lower GI Tract Radiography? What is Lower GI Tract X-ray Radiography (Barium Enema)? Lower gastrointestinal ( ...

  10. COMPARISON OF WIRELESS DETECTORS FOR DIGITAL RADIOGRAPHY SYSTEMS: IMAGE QUALITY AND DOSE.

    Science.gov (United States)

    Mourik, J E M; van der Tol, P; Veldkamp, W J H; Geleijns, J

    2016-06-01

    The purpose of this study was to compare dose and image quality of wireless detectors for digital chest radiography. Entrance dose at both the detector (EDD) and phantom (EPD) and image quality were measured for wireless detectors of seven different vendors. Both the local clinical protocols and a reference protocol were evaluated. In addition, effective dose was calculated. Main differences in clinical protocols involved tube voltage, tube current, the use of a small or large focus and the use of additional filtration. For the clinical protocols, large differences in EDD (1.4-11.8 µGy), EPD (13.9-80.2 µGy) and image quality (IQFinv: 1.4-4.1) were observed. Effective dose was systems. Although effective dose is low, further improvement of imaging technology and acquisition protocols is warranted for optimisation of digital chest radiography.

  11. Use of fluorescent screens for isotope radiography

    Energy Technology Data Exchange (ETDEWEB)

    Hubbard, S. K.

    1979-01-01

    Radiographic examination can be performed on items beyond the limitation of conventional isotope radiography without a great loss of resolution. With proper film and screen selection and scatter radiation control, fluorescent screens can be a valuable additional tool for radiography.

  12. Chest X-Ray

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    Full Text Available ... Therapy November 8 is the International Day of Radiology (IDoR) Radiology and You Sponsored by Image/Video Gallery Your Radiologist Explains Chest X-ray Transcript Welcome to Radiology Info dot org! Hello, I’m Dr. Geoffrey ...

  13. MRI of the Chest

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    Full Text Available ... of which shows a thin slice of the body. The images can then be studied from different angles by ... bear denotes child-specific content. Related Articles and Media MR ... Images related to Magnetic Resonance Imaging (MRI) - Chest Sponsored ...

  14. MRI of the Chest

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    Full Text Available ... vessels and heart chambers. display lymph nodes and blood vessels, including vascular and lymphatic malformations of the chest. assess disorders ... aneurysms some types of metal coils placed within blood vessels nearly all cardiac defibrillators and pacemakers You should ...

  15. CT angiography - chest

    Science.gov (United States)

    ... look for a possible site to insert a catheter for hemodialysis For swelling of the face or upper arms that cannot be explained To look for a suspected birth defect of the aorta or other blood vessels in the chest To look for a balloon dilation of an artery (aneurysm) To look for ...

  16. MRI of the Chest

    Medline Plus

    Full Text Available ... vertebrae, ribs and sternum) and chest wall soft tissue (muscles and fat). assess for pericardial (thin sac around the heart) disease. characterize mediastinal or pleural lesions seen by other ... chemical changes in the tissues. As the hydrogen atoms return to their usual ...

  17. Improving early diagnosis of pulmonary infections in patients with febrile neutropenia using low-dose chest computed tomography

    NARCIS (Netherlands)

    Gerritsen, M G; Willemink, M J; Pompe, E; van der Bruggen, T; van Rhenen, A; Lammers, J W J|info:eu-repo/dai/nl/071697624; Wessels, F; Sprengers, R W; de Jong, Pim|info:eu-repo/dai/nl/287955672; Minnema, M C|info:eu-repo/dai/nl/171618149

    2017-01-01

    We performed a prospective study in patients with chemotherapy induced febrile neutropenia to investigate the diagnostic value of low-dose computed tomography compared to standard chest radiography. The aim was to compare both modalities for detection of pulmonary infections and to explore

  18. 'Aorta-in-aorta' sign on chest radiograph representing enlarged left superior intercostal and hemiazygos veins

    Energy Technology Data Exchange (ETDEWEB)

    Sung, Yon Mi; Lee, Kyung Soo; Kim, Tae Sung [School of Medicine, Sungkyunkwan Univ., Seoul (Korea, Republic of)

    2002-06-01

    We recently encountered a patient with membranous obstruction of the inferior vena cava in whom the left superior intercostal and hemiazygos veins were dilated. At chest radiography, the dilation simulated the presence of a second aortic knob and descending thoracic aorta lateral to the originals, and an 'aorta-in-aorta' appearance was thus created.

  19. A pilot study evaluating erect chest imaging in children, using the Lodox Statscan digital X-ray machine

    Directory of Open Access Journals (Sweden)

    Rupesh Baloo Daya

    2009-11-01

    Full Text Available ABSTRACT Background: Chest radiography accounts for a significant proportion of ionising radiation in children. The radiation dose of radiographs performed on the Lodox Statscan system has been shown to be lower than that of a computed radiography (CR system. The role of the Lodox Statscan (hereafter referred to as the Statscan in routine erect chest radiography in children has not been evaluated. Objective: To evaluate the image quality and diagnostic accuracy of erect paediatric chest radiographs obtained with the Statscan and compare this with conventional erect chest images obtained with a CR system. Materials and Methods: Thirty three children with suspected chest pathology were enrolled randomly over a period of three months. Erect chest radiographs were obtained with the Statscan, and a Shimadzu R-20J X-ray machine coupled with a Fuji FCR 5000 CR system. Image quality and diagnostic accuracy and diagnostic capability were evaluated between the two modalities. Results: The erect Statscan allowed superior visualisation of the three major airways. Statscan images however, demonstrated exposure and movement artifacts with hemidiaphragms and ribs most prone to movement. Bronchovascular clarity was also considered unsatisfactory on the Statscan images. Conclusion: The Statscan has limitations in erect chest radiography in terms of movement artefacts, exposure fluctuations, and poor definition of lung markings. Despite this, the Statscan allows better visualisation of the major airways, equivalent to a ‘high KV’ film at a fraction of the radiation dose. This supports the finding of an earlier study evaluating Statscan images in trauma cases, where the images were taken supine. Statscan has great potential in assisting in the diagnosis of childhood tuberculosis where airway narrowing occurs as a result of nodal compression.

  20. Practical application of suspension criteria scenarios in general radiography, computed radiography,digital radiography and fluoroscopy.

    Science.gov (United States)

    O'Connor, U; Gallagher, A; O'Reilly, G; Dowling, A; Malone, J F

    2013-02-01

    Radiological equipment must be assessed against criteria for acceptability to ensure that it meets the minimum standards for patient safety. This assessment is typically led by a medical physicist with input from radiology staff and the equipment supplier. Equipment that does not meet the criteria requires action and may be suspended from clinical use. European Commission report RP 91 will be revised and replaced as RP 162. It has been drawn up to aid medical physicists with the assessment process and provide guidance on suspension levels. This paper details several cases where the criteria in the proposed RP 162 were applied in general radiography, computed radiography, digital radiography and fluoroscopy. The factors considered by the medical physicist and the outcome of each case are presented. The proposed RP 162 report improves on its predecessor and provides a robust set of criteria for ensuring that patient safety within the EU medical exposures framework is optimised.

  1. Sandstorm in the chest?

    Directory of Open Access Journals (Sweden)

    Talluri MR

    2011-07-01

    Full Text Available A 32 year old female presented with dry cough and progressive breathlessness of one year duration. There was no history suggestive of collagen vascular disease, lung parenchymal infection or allergic airway disease. Clinical evaluation showed basal fine inspiratory crepitations. Radiographic examination of the chest revealed a black pleura line and lung parenchymal calcification. CT scan of the chest demonstrated nodular calcification of lung parenchyma with a “crazy pavement” pattern, which is suggestive of alveolar calcification. Pulmonary function test showed a severe restrictive defect. On transbronchial lung biopsy calcific spherules suggestive of the alveolar microlithiasis were seen. Diagnosis of pulmonary alveolar microlithiasis was made and symptomatic treatment was given, as there is no specific therapy available. The case illustrates an unusual cause of shortness of breath in a young female with striking radiographic features.

  2. CHEST PHYSIOTHERAPY FOR INFANTS

    OpenAIRE

    2014-01-01

    In the normal lung, secretions are removed by Mucociliary activity, normal breathing cycles, and cough. In disease, increased secretion viscosity and volume, dyskinesia of the cilia, and ineffective cough combine to reduce the ability to clear secretions, and may increase exacerbations and infections. Many chest physiotherapy techniques like postural drainage, percussion and vibration are used since many years. These techniques are derived from adult studies but these techniques are quite str...

  3. Posteroanterior chest X-ray for the diagnosis of pneumothorax: methods, usage, and resolution

    Directory of Open Access Journals (Sweden)

    Denise Rossato Silva

    2010-08-01

    Full Text Available Denise Rossato Silva, Sandra Jungblut Schuh, Paulo de Tarso Roth DalcinUniversidade Federal do Rio Grande do Sul, Porto Alegre-RS, BrazilAbstract: Most pneumothoraces are demonstrated on fully inspired erect posteroanterior (PA chest X-ray (CXR. Expiratory films may have a role in the clinical management of patients with a small respiratory reserve in whom pneumothorax is suspected and not demonstrated on the inspiratory film. PA CXR can be used for the diagnosis of spontaneous and ­nonspontaneous pneumothoraces. When digital radiography is used, for most authors, a 2.5-lp/mm spatial ­resolution is satisfactory to detect a pneumothorax.Keywords: radiography, computed tomography, pneumothorax, posteroanterior chest X-ray

  4. Noise simulation system for determining imaging conditions in digital radiography

    Science.gov (United States)

    Tanaka, R.; Ichikawa, K.; Matsubara, K.; Kawashima, H.

    2012-03-01

    Reduction of exposure dose and improvement in image quality can be expected to result from advances in the performance of imaging detectors. We propose a computerized method for determining optimized imaging conditions by use of simulated images. This study was performed to develop a prototype system for image noise and to ensure consistency between the resulting images and actual images. An RQA5 X-ray spectrum was used for determination of input-output characteristics of a flat-panel detector (FPD). The number of incident quantum to the detector per pixel (counts/pixel) was calculated according to the pixel size of the detector and the quantum number in RQA5 determined in IEC6220-1. The relationship among tube current-time product (mAs), exposure dose (C/kg) at the detector surface, the number of incident quanta (counts/pixel), and pixel values measured on the images was addressed, and a conversion function was then created. The images obtained by the FPD was converted into a map of incident quantum numbers and input into random-value generator to simulate image noise. In addition, graphic user interface was developed to observe images with changing image noise and exposure dose levels, which have trade-off relationship. Simulation images provided at different noise levels were compared with actual images obtained by the FPD system. The results indicated that image noise was simulated properly both in objective and subjective evaluation. The present system could allow us to determine necessary dose from image quality and also to estimate image quality from any exposure dose.

  5. Construction of pediatric homogeneous phantoms for optimization of chest and skull radiographs

    Energy Technology Data Exchange (ETDEWEB)

    Alves, Allan Felipe Fattori, E-mail: allan@ibb.unesp.br [Instituto de Biociências de Botucatu, P.O. BOX 510, Departamento de Física e Biofísica, UNESP—Universidade Estadual Paulista, Distrito de Rubião Junior S/N, Botucatu, 18618-000 São Paulo (Brazil); Miranda, José Ricardo de Arruda, E-mail: jmiranda@ibb.unesp.br [Instituto de Biociências de Botucatu, Departamento de Física e Biofísica, UNESP—Universidade Estadual Paulista, Distrito de Rubião Junior S/N, Botucatu, 18618-000 São Paulo (Brazil); Bacchim Neto, Fernando Antonio, E-mail: fernando.bacchim@gmail.com [Instituto de Biociências de Botucatu, Departamento de Física e Biofísica, UNESP—Universidade Estadual Paulista, Distrito de Rubião Junior S/N, Botucatu, 18618-000 São Paulo (Brazil); Duarte, Sérgio Barbosa, E-mail: sbd@cbpf.br [Centro Brasileiro de Pesquisas Físicas, Laboratório de Altas Energias, Dr. Xavier Sigaud, 150, Rio de Janeiro, 22290-180 Rio de Janeiro (Brazil); Pina, Diana Rodrigues de, E-mail: drpina@fmb.unesp.br [Departamento de Doenças Tropicais e Diagnóstico por Imagem, Faculdade de Medicina de Botucatu, UNESP—Universidade Estadual Paulista, Distrito de Rubião Junior S/N, Botucatu, 18618-000 São Paulo (Brazil)

    2015-08-15

    Highlights: • We developed two pediatric patient-equivalent phantoms. • Our phantoms were used in the optimization process of computed radiography systems. • We evaluated physical quantities such as effective detective quantum efficiency and contrast-to-noise ratio. • We determined optimized techniques for pediatric protocols. - Abstract: Objectives: To develop two pediatric patient-equivalent phantoms, the Pediatric Chest Equivalent Patient (PCEP) and the Pediatric Skull Equivalent Patient (PSEP) for children aged 1 to 5 years. We also used both phantoms for image quality evaluations in computed radiography systems to determine Gold Standard (GS) techniques for pediatric patients. Methods: To determine the simulator materials thickness (Lucite and aluminum), we quantified biological tissues (lung, soft, and bone) using an automatic computational algorithm. To objectively establish image quality levels, two physical quantities were used: effective detective quantum efficiency and contrast-to-noise ratio. These quantities were associated to values obtained for standard patients from previous studies. Results: For chest radiographies, the GS technique applied was 81 kVp, associated to 2.0 mAs and 83.6 μGy of entrance skin dose (ESD), while for skull radiographies, the GS technique was 70 kVp, associated to 5 mAs and 339 μGy of ESD. Conclusion: This procedure allowed us to choose optimized techniques for pediatric protocols, thus improving quality of diagnosis for pediatric population and reducing diagnostic costs to our institution. These results could also be easily applied to other services with different equipment technologies.

  6. The neonatal chest

    Energy Technology Data Exchange (ETDEWEB)

    Lobo, Luisa [Servico de Imagiologia Geral do Hospital de Santa Maria, Av. Prof. Egas Moniz, 1649-035 Lisbon (Portugal)]. E-mail: mluisalobo@gmail.com

    2006-11-15

    Lung diseases represent one of the most life threatening conditions in the newborn. Important progresses in modern perinatal care has resulted in a significantly improved survival and decreased morbidity, in both term and preterm infants. Most of these improvements are directly related to the better management of neonatal lung conditions, and infants of very low gestational ages are now surviving. This article reviews the common spectrum of diseases of the neonatal lung, including medical and surgical conditions, with emphasis to the radiological contribution in the evaluation and management of these infants. Imaging evaluation of the neonatal chest, including the assessment of catheters, lines and tubes are presented.

  7. Mucopolysaccharidosis: abnormal findings on abdomen and chest excluding musculoskeletal system

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Jeung Hee; Yoon, Dae Young; Seo, Young Lan; Han, Dae Hee; Choi, Chul Soon; Bae, Sang Hoon; Yoon, Young Cheol; Park, Sang Joon [Samsung Medical Center, Seoul (Korea, Republic of); Kim Han, Bok Yung; Yoon, Hye Kyung; Cho, Jae Min [Hallym University College of Medicine, Seoul (Korea, Republic of)

    2003-06-01

    Mucopolysaccharidosis (MPS) is a lysosomal storage disease that causes tissue distortion and dysfunction due to the infiltration of mucopolysaccharide in connective tissue. The purpose of this study was to evaluate the characteristic findings of abdominal CT and plain chest radiography in patients with MPS. Sixty-two children with MPS diagnosed by urine analysis were involved in this study; 24 of these underwent abdominal CT and the findings were reviewed by two radiologists, who reached a consensus. Organomegaly was classified as severe, moderate or mild. On chest PA radiographs of 42 of the children, the transverse diameter of the trachea was measured and compared with that of 42 normal controls. Student's t test was used for statistical analysis. At abdominal CT, hepatomegaly was observed in 22 patients (92%; 2 severe, 15 moderate and 5 mild); and splenomegaly was present in 18 (75%; 2 severe, 4 moderate and 12 mild). Among eight patients(33%) with pancreatic enlargement, one had a severly enlarged pancreas, while in the remaining seven, enlargement was mild. Also present were inguinal hernia (n=15), umbilical hernia (n=12), undulation with thickening of the diaphragmatic crura (n=10), abnormalities related to the male genitalia (n=5) and vascular anomaly (n=3). In MPS patients, the mid-point diameter of the trachea (range, 5.6-9 mm; mean, 6.9 mm) was significantly less than in normal controls (range, 8-14 mm; mean, 10.8 mm) (p<0.001). An awareness of the characteristic abnormalities observed at abdominal CT and chest PA radiography can lead to a better understanding of MPS in children.

  8. Mucopolysaccharidosis: abnormal findings on abdomen and chest excluding musculoskeletal system

    Energy Technology Data Exchange (ETDEWEB)

    KimHan, Bo Kyung; Yoon, Hye Kyung; Cho, Jae Min [Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Moon, Jeung Hee; Yoon, Dae Young; Seo, Young Lan; Han, Dae Hee; Choi, Chul Soon; Bae, Sang Hoon; Yoon, Young Cheol; Park, Sang Joon [Hallym University College of Medicine, Seoul (Korea, Republic of)

    2003-06-01

    Mucopolysaccharidosis (MPS) is a lysosomal storage disease that causes tissue distortion and dysfunction due to the infiltration of mucopolysaccharide in connective tissue. The purpose of this study was to evaluate the characteristic findings of abdominal CT and plain chest radiography in patients with MPS. Sixty-two children with MPS diagnosed by urine analysis were involved in this study; 24 of these underwent abdominal CT and the findings were reviewed by two radiologists, who reached a consensus. Organomegaly was classified as severe, moderate or mild. On chest PA radiographs of 42 of the children, the transverse diameter of the trachea was measured and compared with that of 42 normal controls. Student's t test was used for statistical analysis. At abdominal CT, hepatomegaly was observed in 22 patients (92%; 2 severe, 15 moderate and 5 mild); and splenomegaly was present in 18 (75%; 2 severe, 4 moderate and 12 mild). Among eight patients (33%) with pancreatic enlargement, one had a severly enlarged pancreas, while in the remaining seven, enlargement was mild. Also present were inguinal hernia (n=15), umbilical hernia (n=12), undulation with thickening of the diaphragmatic crura (n=10). abnormalities related to the male genitalia (n=5) and vascular anomaly (n=3). In MPS patients, the mid-point diameter of the trachea (range, 5.6-9 mm; mean, 6.9 mm) was significantly less than in normal controls (range, 8-14 mm; mean, 10.8 mm)(p<0.001). An awareness of the characteristic abnormalities observed at abdominal CT and chest PA radiography can lead to a better understanding of MPS in children.

  9. Tomografia computadorizada de alta resolução na silicose: correlação com radiografia e testes de função pulmonar High-resolution computed tomography in silicosis: correlation with chest radiography and pulmonary function tests

    Directory of Open Access Journals (Sweden)

    Agnaldo José Lopes

    2008-05-01

    Full Text Available OBJETIVO: Correlacionar os parâmetros tomográficos com os de função pulmonar em portadores de silicose, bem como comparar os resultados da tomografia computadorizada de alta resolução (TCAR com os da radiografia de tórax. MÉTODOS: Foi realizado um estudo de corte transversal, em que foram avaliados 44 pacientes não-tabagistas e sem história pregressa de tuberculose. As radiografias foram classificadas de acordo com a proposta da Organização Internacional do Trabalho. Utilizando um sistema de escore semiquantitativo, os seguintes achados na TCAR foram quantificados: extensão total do envolvimento pulmonar, opacidades parenquimatosas e enfisema. Foram realizados espirometria, oscilações forçadas, avaliação dos volumes pulmonares pela técnica de diluição com hélio e medida da diffusing capacity of the lung for carbon monoxide (DLCO, capacidade de difusão do monóxido de carbono. RESULTADOS: Dos 44 pacientes estudados, 41 eram homens, com média de idade de 48,4 anos. Na análise comparativa, 4 pacientes classificados na categoria 0 pela radiografia foram reclassificados na categoria 1 pela TCAR e, enquanto a radiografia diagnosticou 23 casos de fibrose maciça progressiva, a TCAR estabeleceu esse diagnóstico em 33 doentes. Para o escore de opacidades, as maiores correlações foram observadas com as medidas de fluxo, DLCO e complacência. Já o enfisema correlacionou-se negativamente com as medidas de volume, DLCO e fluxo. Nesta amostra com predomínio de grandes opacidades (75% dos indivíduos, a deterioração da função pulmonar associou-se com a extensão das alterações estruturais. CONCLUSÕES: Na silicose, a TCAR é superior à radiografia tanto na detecção precoce da doença quanto na identificação de fibrose maciça progressiva.OBJECTIVE: To correlate tomographic findings with pulmonary function findings, as well as to compare chest X-ray findings with high resolution computed tomography (HRCT findings, in

  10. Chest physiotherapy compared to no chest physiotherapy for cystic fibrosis.

    NARCIS (Netherlands)

    A. Gates; L. Warnock; Dr. C.P. van der Schans

    2013-01-01

    BACKGROUND: Chest physiotherapy is widely used in people with cystic fibrosis in order to clear mucus from the airways. OBJECTIVES: To determine the effectiveness and acceptability of chest physiotherapy compared to no treatment or spontaneous cough alone to improve mucus clearance in cystic

  11. Fully automated calculation of cardiothoracic ratio in digital chest radiographs

    Science.gov (United States)

    Cong, Lin; Jiang, Luan; Chen, Gang; Li, Qiang

    2017-03-01

    The calculation of Cardiothoracic Ratio (CTR) in digital chest radiographs would be useful for cardiac anomaly assessment and heart enlargement related disease indication. The purpose of this study was to develop and evaluate a fully automated scheme for calculation of CTR in digital chest radiographs. Our automated method consisted of three steps, i.e., lung region localization, lung segmentation, and CTR calculation. We manually annotated the lung boundary with 84 points in 100 digital chest radiographs, and calculated an average lung model for the subsequent work. Firstly, in order to localize the lung region, generalized Hough transform was employed to identify the upper, lower, and outer boundaries of lung by use of Sobel gradient information. The average lung model was aligned to the localized lung region to obtain the initial lung outline. Secondly, we separately applied dynamic programming method to detect the upper, lower, outer and inner boundaries of lungs, and then linked the four boundaries to segment the lungs. Based on the identified outer boundaries of left lung and right lung, we corrected the center and the declination of the original radiography. Finally, CTR was calculated as a ratio of the transverse diameter of the heart to the internal diameter of the chest, based on the segmented lungs. The preliminary results on 106 digital chest radiographs showed that the proposed method could obtain accurate segmentation of lung based on subjective observation, and achieved sensitivity of 88.9% (40 of 45 abnormalities), and specificity of 100% (i.e. 61 of 61 normal) for the identification of heart enlargements.

  12. Are chest radiographs routinely necessary following thoracostomy tube removal?

    Energy Technology Data Exchange (ETDEWEB)

    Pacharn, Preeyacha; Heller, Daniel N.D.; Kammen, Bamidele F.; Bryce, Thomas J.; Bailey, Richard A.; Brasch, Robert C. [Department of Radiology, University of California San Francisco, CA (United States); Reddy, Mohan V. [Department of Surgery, University of California San Francisco (United States)

    2002-02-01

    Objective: Chest radiographs (CXRs) are routinely obtained at many institutions in all pediatric patients following thoracostomy tube removal to search for pneumothorax (PTX). To aid in evaluating the necessity of this practice, this study investigates whether clinical signs and symptoms may be a sensitive predictor of PTX in such patients. Materials and methods: Reports from CXRs obtained following chest tube removal in all pediatric patients (374 patients) who underwent cardiac surgery with chest tube placement over 1 year were reviewed. For cases with reported PTX, the PTX was quantified and chart review was performed to assess whether signs and symptoms of PTX preceded the CXR result. Results: Fifty-one of 374 children (13.6%) had a radiographically defined PTX within 6 h after thoracostomy tube removal. The PTX was large (>40%) in 2 children, moderate (20-40%) in 5 children, and small (<20%) in 44 children. Symptoms (dyspnea, tachypnea, respiratory distress) or signs (increased oxygen requirement, worsening arterial blood gas and/or hypotension) of respiratory distress were present at the time of the initial CXR in six of seven patients, who later underwent a major clinical intervention, and in one patient who did not. Major clinical interventions were performed in all patients with a large PTX, four of five patients with a moderate PTX, and one patient with a small PTX that later enlarged. Conclusions: Clinical signs and symptoms identified nearly all patients with significant pneumothoraces. Future prospective investigations may examine reserving chest radiography following chest tube removal for select groups, such as symptomatic patients or those with tenuous cardiovascular status. (orig.)

  13. Incidental findings in chest X-rays; Zufallsbefunde im Roentgenthorax

    Energy Technology Data Exchange (ETDEWEB)

    Wielpuetz, M.O.; Kauczor, H.U. [Universitaetsklinikum Heidelberg, Klinik fuer Diagnostische und Interventionelle Radiologie, Heidelberg (Germany); Universitaet Heidelberg, Translational Lung Research Center (TLRC), Deutsches Zentrum fuer Lungenforschung (DZL), Heidelberg (Germany); Universitaetsklinikum Heidelberg, Klinik fuer Diagnostische und Interventionelle Radiologie mit Nuklearmedizin, Thoraxklinik, Heidelberg (Germany); Weckbach, S. [Universitaetsklinikum Heidelberg, Klinik fuer Diagnostische und Interventionelle Radiologie, Heidelberg (Germany); Universitaet Heidelberg, Translational Lung Research Center (TLRC), Deutsches Zentrum fuer Lungenforschung (DZL), Heidelberg (Germany)

    2017-04-15

    Conventional projection radiography (chest x-ray) is one of the most frequently requested procedures in radiology. Even though chest x-ray imaging is frequently performed in asymptomatic patients for preoperative assessment, clinically relevant incidental findings are relatively scarce. This is due to the relatively low sensitivity of chest x-rays where few clinically relevant incidental findings are to be expected, as any detectable pathologies will as a rule already be clinically symptomatic. Recommendations from relevant societies for the management of incidental findings, apart from the clarification of incidental nodules, do not exist. This review article therefore describes the most frequent and typical incidental findings of lung parenchyma (apart from pulmonary nodules), mediastinal structures including the hilum of the lungs, pleura, chest wall and major vessels. Also described are those findings which can be diagnosed with sufficient certainty from chest x-rays so that further clarification is not necessary and those which must be further clarified by multislice imaging procedures or other techniques. (orig.) [German] Eine der haeufigsten Untersuchungen in der Radiologie ist die konventionelle Projektionsradiographie des Thorax (Roentgenthorax). Auch wenn projektionsradiographische Aufnahmen im Rahmen einer praeoperativen Abklaerung haeufig als orientierende Untersuchung angefertigt werden, sind - bedingt durch die relativ geringe Sensitivitaet des Roentgenthorax - wenig klinisch relevante Zufallsbefunde zu erwarten, da nachweisbare Pathologien in der Regel bereits auch klinisch apparent sind. Empfehlungen entsprechender Fachgesellschaften zu Zufallsbefunden im Roentgenthorax jenseits der Abklaerung von Rundherden liegen nicht vor. Die vorliegende Arbeit beleuchtet daher haeufige und typische Zufallsbefunde des Lungenparenchyms (ausser den Lungenrundherden), der mediastinalen Strukturen einschliesslich der Hili, der Pleura, der Thoraxwand sowie der

  14. Fracture healing: direct magnification versus conventional radiography

    Energy Technology Data Exchange (ETDEWEB)

    Link, T.M. [Dept. of Clinical Radiology, Westfaelische Wilhelms-Univ., Muenster (Germany); Kessler, T. [Dept. of Traumatic and Hand Surgery, Westfaelische Wilhelms-Univ., Muenster (Germany); Lange, T. [Dept. of Clinical Radiology, Westfaelische Wilhelms-Univ., Muenster (Germany); Overbeck, J. [Dept. of Traumatic and Hand Surgery, Westfaelische Wilhelms-Univ., Muenster (Germany); Fiebich, M. [Dept. of Clinical Radiology, Westfaelische Wilhelms-Univ., Muenster (Germany); Peters, P.E. [Dept. of Clinical Radiology, Westfaelische Wilhelms-Univ., Muenster (Germany)

    1994-08-01

    The aim of the study was to evaluate the potential of magnification radiography in diagnosing fracture healing and assessing its complications. Seventy-three patients with fractures or who had undergone osteotomy were radiographed with both conventional (non-magnified) and magnification (5-fold) techniques. Since 10 patients were radiographed twice and 1 three times, 83 radiographs using each technique were obtained. All radiographs were analysed and the findings correlated with the patients` follow-up studies. The microfocal X-ray unit used for magnification radiography had a focal spot size of 20-130 {mu}m. As an imaging system, digital luminescence radiography was employed with magnification, while normal film-screen systems were used with conventional radiography. Magnification radiography proved superior to conventional radiography in 47% of cases: endosteal and periosteal callus formations were seen earlier and better in 26 cases, and osseous union could be evaluated with greater certainty in 33 cases. In 49% of cases magnification radiography was equal and in 4% inferior to conventional radiography. Additionally an ``inter-observer analysis`` was carried out. Anatomical and pathological structures were classified into one of four grades. Results were significantly (P < 0.01) better using magnification radiography. We conclude that the magnification technique is a good method for monitoring fracture healing in its early stages. (orig.)

  15. Computed radiography (FCR) with a dual side reading system. Comparison with conventional radiography for visualization of nodular lung cancers

    Energy Technology Data Exchange (ETDEWEB)

    Ha-kawa, Shangkil; Yoshida, Tsunetaka; Sougawa, Mitsuharu; Harima, Yohko; Sawada, Satoshi [Kansai Medical Univ., Moriguchi, Osaka (Japan)

    2003-02-01

    To assess the diagnostic capability Fuji computed radiography (FCR) using a dual side reading system was compared to the conventional radiography using a film-screen system. Twenty-eight patients with lung cancer were examined with a new FCR system (FCR 5501D) and a conventional screen-film system concurrently. FCR utilizes a reading system that detects emissions from dual sides of imaging plate. Chest X-rays were obtained with same exposure factors in both systems. Image qualities of both systems were compared by two radiologists using a five-level score. There were no lesion that FCR images were inferior to film-screen images. The frequency of score +1 or +2 that FCR images were superior to film-screen images was 31% in large nodular shadows, 40% in accompanying shadows with a nodule, 67% of small nodular shadows, and 43% of the lymph node swelling in the hilum of the lung or mediastinum. In large nodular shadows which were the most frequent abnormality score +1 or +2 were observed in 43% of adenocarcinoma and 26% of squamous cell lung cancer. FCR with the dual side reading system is superior to the conventional screen-film system for visualization of nodular lung cancers. (author)

  16. Initial clinical evaluation of stationary digital chest tomosynthesis

    Science.gov (United States)

    Hartman, Allison E.; Shan, Jing; Wu, Gongting; Lee, Yueh Z.; Zhou, Otto; Lu, Jianping; Heath, Michael; Wang, Xiaohui; Foos, David

    2016-03-01

    Computed Tomography (CT) is the gold standard for image evaluation of lung disease, including lung cancer and cystic fibrosis. It provides detailed information of the lung anatomy and lesions, but at a relatively high cost and high dose of radiation. Chest radiography is a low dose imaging modality but it has low sensitivity. Digital chest tomosynthesis (DCT) is an imaging modality that produces 3D images by collecting x-ray projection images over a limited angle. DCT is less expensive than CT and requires about 1/10th the dose of radiation. Commercial DCT systems acquire the projection images by mechanically scanning an x-ray tube. The movement of the tube head limits acquisition speed. We recently demonstrated the feasibility of stationary digital chest tomosynthesis (s-DCT) using a carbon nanotube (CNT) x-ray source array in benchtop phantom studies. The stationary x-ray source allows for fast image acquisition. The objective of this study is to demonstrate the feasibility of s-DCT for patient imaging. We have successfully imaged 31 patients. Preliminary evaluation by board certified radiologists suggests good depiction of thoracic anatomy and pathology.

  17. [Musculoskeletal-related chest pain].

    Science.gov (United States)

    Sturm, C; Witte, T

    2017-01-01

    Approximately 10-50% of chest pains are caused by musculoskeletal disorders. The association is twice as frequent in primary care as in emergency admissions. This article provides an overview of the most important musculoskeletal causes of chest pain and on the diagnostics and therapy. A selective search and analysis of the literature related to the topic of musculoskeletal causes of chest pain were carried out. Non-inflammatory diseases, such as costochondritis and fibromyalgia are frequent causes of chest pain. Inflammatory diseases, such as rheumatoid arthritis, spondyloarthritis and systemic lupus erythematosus are much less common but are more severe conditions and therefore have to be diagnosed and treated. The diagnostics and treatment often necessitate interdisciplinary approaches. Chest pain caused by musculoskeletal diseases always represents a diagnosis by exclusion of other severe diseases of the heart, lungs and stomach. Physiotherapeutic and physical treatment measures are particularly important, including manual therapy, transcutaneous electrical stimulation and stabilization exercises, especially for functional myofascial disorders.

  18. Measurement of Entrance Surface Dose on an Anthropomorphic Thorax Phantom Using a Miniature Fiber-Optic Dosimeter

    Science.gov (United States)

    Yoo, Wook Jae; Shin, Sang Hun; Jeon, Dayeong; Hong, Seunghan; Sim, Hyeok In; Kim, Seon Geun; Jang, Kyoung Won; Cho, Seunghyun; Youn, Won Sik; Lee, Bongsoo

    2014-01-01

    A miniature fiber-optic dosimeter (FOD) system was fabricated using a plastic scintillating fiber, a plastic optical fiber, and a multi-pixel photon counter to measure real-time entrance surface dose (ESD) during radiation diagnosis. Under varying exposure parameters of a digital radiography (DR) system, we measured the scintillating light related to the ESD using the sensing probe of the FOD, which was placed at the center of the beam field on an anthropomorphic thorax phantom. Also, we obtained DR images using a flat panel detector of the DR system to evaluate the effects of the dosimeter on image artifacts during posteroanterior (PA) chest radiography. From the experimental results, the scintillation output signals of the FOD were similar to the ESDs including backscatter simultaneously obtained using a semiconductor dosimeter. We demonstrated that the proposed miniature FOD can be used to measure real-time ESDs with minimization of DR image artifacts in the X-ray energy range of diagnostic radiology. PMID:24694678

  19. Measurement of Entrance Surface Dose on an Anthropomorphic Thorax Phantom Using a Miniature Fiber-Optic Dosimeter

    Directory of Open Access Journals (Sweden)

    Wook Jae Yoo

    2014-04-01

    Full Text Available A miniature fiber-optic dosimeter (FOD system was fabricated using a plastic scintillating fiber, a plastic optical fiber, and a multi-pixel photon counter to measure real-time entrance surface dose (ESD during radiation diagnosis. Under varying exposure parameters of a digital radiography (DR system, we measured the scintillating light related to the ESD using the sensing probe of the FOD, which was placed at the center of the beam field on an anthropomorphic thorax phantom. Also, we obtained DR images using a flat panel detector of the DR system to evaluate the effects of the dosimeter on image artifacts during posteroanterior (PA chest radiography. From the experimental results, the scintillation output signals of the FOD were similar to the ESDs including backscatter simultaneously obtained using a semiconductor dosimeter. We demonstrated that the proposed miniature FOD can be used to measure real-time ESDs with minimization of DR image artifacts in the X-ray energy range of diagnostic radiology.

  20. Measurement of entrance surface dose on an anthropomorphic thorax phantom using a miniature fiber-optic dosimeter.

    Science.gov (United States)

    Yoo, Wook Jae; Shin, Sang Hun; Jeon, Dayeong; Hong, Seunghan; Sim, Hyeok In; Kim, Seon Geun; Jang, Kyoung Won; Cho, Seunghyun; Youn, Won Sik; Lee, Bongsoo

    2014-04-01

    A miniature fiber-optic dosimeter (FOD) system was fabricated using a plastic scintillating fiber, a plastic optical fiber, and a multi-pixel photon counter to measure real-time entrance surface dose (ESD) during radiation diagnosis. Under varying exposure parameters of a digital radiography (DR) system, we measured the scintillating light related to the ESD using the sensing probe of the FOD, which was placed at the center of the beam field on an anthropomorphic thorax phantom. Also, we obtained DR images using a flat panel detector of the DR system to evaluate the effects of the dosimeter on image artifacts during posteroanterior (PA) chest radiography. From the experimental results, the scintillation output signals of the FOD were similar to the ESDs including backscatter simultaneously obtained using a semiconductor dosimeter. We demonstrated that the proposed miniature FOD can be used to measure real-time ESDs with minimization of DR image artifacts in the X-ray energy range of diagnostic radiology.

  1. Diagnostic Accuracy of Ultrasonography and Radiography in Detection of Pulmonary Contusion; a Systematic Review and Meta-Analysis

    OpenAIRE

    HOSSEINI, Mostafa; Ghelichkhani, Parisa; Baikpour, Masoud; Tafakhori, Abbas; Asady, Hadi; Haji Ghanbari, Mohammad Javad; Yousefifard, Mahmoud; Safari, Saeed

    2015-01-01

    Introduction: Ultrasonography is currently being used as one of the diagnostic modalities in various medical emergencies for screening of trauma patients. The diagnostic value of this modality in detection of traumatic chest injuries has been evaluated by several studies but its diagnostic accuracy in diagnosis of pulmonary contusion is a matter of discussion. Therefore, the present study aimed to determine the diagnostic accuracy of ultrasonography and radiography in detection of pulmonary c...

  2. Multiple imaging radiography at LNLS

    Energy Technology Data Exchange (ETDEWEB)

    Hoennicke, M.G. [LORXI, Departamento de Fisica, Universidade Federal do Parana, Caixa Postal 19091, 81531-990 Curitiba (Brazil)], E-mail: marcelohonnicke@yahoo.com.br; Cusatis, C. [LORXI, Departamento de Fisica, Universidade Federal do Parana, Caixa Postal 19091, 81531-990 Curitiba(Brazil); Antunes, A. [Departamento de Fisica Aplicada, Instituto de Fisica, Universidade de Sao Paulo, Caixa Postal 66318, 05315-970 Sao Paulo (Brazil); Safatle, A.M.V.; Barros, P.S.M. [Laboratorio de Oftalmologia Experimental e Comparativa, Departamento de Cirurgia, Faculdade de Medicina Veterinaria, Universidade de Sao Paulo, 05508-900 Sao Paulo (Brazil); Morelhao, S.L. [Departamento de Fisica Aplicada, Instituto de Fisica, Universidade de Sao Paulo, Caixa Postal 66318, 05315-970 Sao Paulo (Brazil)

    2008-01-11

    An analyzer-based X-ray phase-contrast imaging (ABI) setup has been mounted at the Brazilian Synchrotron Light Laboratory (LNLS) for multiple imaging radiography (MIR) purposes. The algorithm employed for treating the MIR data collected at LNLS is described, and its reliability in extracting the distinct types of contrast that can be obtained with MIR is demonstrated by analyzing a test sample (thin polyamide wire). As a practical application, the possibility of studying ophthalmic tissues, corneal sequestra in this case, via MIR is investigated.

  3. Computational radiology in skeletal radiography

    Energy Technology Data Exchange (ETDEWEB)

    Peloschek, Ph.; Nemec, S. [Computational Image Analysis and Radiology Lab (CIR), Department of Radiology, Medical University Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Widhalm, P. [Computational Image Analysis and Radiology Lab (CIR), Department of Radiology, Medical University Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Pattern Recognition and Image Processing Group, Department of Computer Aided Automation, Vienna University of Technology, Wiedner Hauptstrasse 8-10/020, A-1040 Vienna (Austria); Donner, R. [Computational Image Analysis and Radiology Lab (CIR), Department of Radiology, Medical University Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Pattern Recognition and Image Processing Group, Department of Computer Aided Automation, Vienna University of Technology, Wiedner Hauptstrasse 8-10/020, A-1040 Vienna (Austria); Institute for Computer Graphics and Vision, Graz University of Technology, Inffeldgasse 16, A-8010 Graz (Austria); Birngruber, E. [Computational Image Analysis and Radiology Lab (CIR), Department of Radiology, Medical University Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Thodberg, H.H. [Visiana Aps, Sollerodvej 57C, DK-2840 Holte (Denmark); Kainberger, F. [Computational Image Analysis and Radiology Lab (CIR), Department of Radiology, Medical University Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Langs, G. [Computational Image Analysis and Radiology Lab (CIR), Department of Radiology, Medical University Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria)], E-mail: georg.langs@meduniwien.ac.at

    2009-11-15

    Recent years have brought rapid developments in computational image analysis in musculo-skeletal radiology. Meanwhile the algorithms have reached a maturity that makes initial clinical use feasible. Applications range from joint space measurement to erosion quantification, and from fracture detection to the assessment of alignment angles. Current results of computational image analysis in radiography are very promising, but some fundamental issues remain to be clarified, among which the definition of the optimal trade off between automatization and operator-dependency, the integration of these tools into clinical work flow and last not least the proof of incremental clinical benefit of these methods.

  4. Paediatric dose measurement in a full-body digital radiography unit

    Energy Technology Data Exchange (ETDEWEB)

    Maree, Gert J.; Hering, Egbert R. [Groote Schuur Hospital and University of Cape Town, Division of Medical Physics, Cape Town (South Africa); Irving, Benjamin J. [University of Cape Town, MRC/UCT Medical Imaging Research Unit, Department of Human Biology, Cape Town, Western Cape (South Africa)

    2007-10-15

    Ionizing radiation has a detrimental effect on the human body, particularly in children. Thus it is important to minimize the dose. Linear slit-scanning X-ray units offer the possibility of dose reductions. In order to further develop linear slit-scanning radiography, the dose needs to be accurately calculated for various examinations. To measure the entrance dose (free-in-air) and calculate the effective doses for various radiological examinations in children on Lodox Statscan and Shimadzu radiography units. Entrance doses (free-in-air) were measured using a dose meter and ionization chamber on the Statscan and Shimadzu units at two South African hospitals. The entrance doses were measured for a number of common examinations and were used to compute the effective dose using a Monte Carlo program. The standard deviation of the entrance doses was in the range 0-0.6%. The effective dose from the Statscan unit was well below that from the Shimadzu unit as well as that found in other radiological studies from around the world in children. The one exception was chest examination where the dose was similar to that in other studies worldwide due to the use of Chest AP projection compared to Chest PA used in the comparitive studies. Linear slit-scanning systems help reduce the dose in radiological examinations in children. (orig.)

  5. NEUTRON RADIOGRAPHY: A SECOND PROGRESS REPORT

    Energy Technology Data Exchange (ETDEWEB)

    Berger, H

    1962-08-31

    The progress made on investigations of neutron radiography since October 1960 is discussed. The problems of the production of the neutron image will be discussed. The emphasis will be on the characteristics of many of the photographic imaging methods which can be used for neutron radiography. (auth)

  6. Process waste assessment for the Radiography Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, N.M.

    1994-07-01

    This Process Waste Assessment was conducted to evaluate the Radiography Laboratory, located in Building 923. It documents the processes, identifies the hazardous chemical waste streams generated by these processes, recommends possible ways to minimize waste, and serves as a reference for future assessments of this facility. The Radiography Laboratory provides film radiography or radioscopy (electronic imaging) of weapon and nonweapon components. The Radiography Laboratory has six x-ray machines and one gamma ray source. It also has several other sealed beta- and gamma-ray isotope sources of low microcurie ({mu}Ci) activity. The photochemical processes generate most of the Radiography Laboratory`s routinely generated hazardous waste, and most of that is generated by the DuPont film processor. Because the DuPont film processor generates the most photochemical waste, it was selected for an estimated material balance.

  7. Novel Influenza A (H1N1) Virus Infection in Children: Chest Radiographic and CT Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Min Jeong; Lee, Young Seok; Lee, Jee Young; Lee, Kun Song [Dankook University College of Medicine, Dankook University Hospital, Cheonan (Korea, Republic of)

    2010-12-15

    The purpose of this study was to evaluate the chest radiographic and CT findings of novel influenza A (H1N1) virus infection in children, the population that is more vulnerable to respiratory infection than adults. The study population comprised 410 children who were diagnosed with an H1N1 infection from August 24, 2009 to November 11, 2009 and underwent chest radiography at Dankook University Hospital in Korea. Six of these patients also underwent chest CT. The initial chest radiographs were classified as normal or abnormal. The abnormal chest radiographs and high resolution CT scans were assessed for the pattern and distribution of parenchymal lesions, and the presence of complications such as atelectasis, pleural effusion, and pneumomediastinum. The initial chest radiograph was normal in 384 of 410 (94%) patients and abnormal in 26 of 410 (6%) patients. Parenchymal abnormalities seen on the initial chest radiographs included prominent peribronchial marking (25 of 26, 96%), consolidation (22 of 26, 85%), and ground-glass opacities without consolidation (2 of 26, 8%). The involvement was usually bilateral (19 of 26, 73%) with the lower lung zone predominance (22 of 26, 85%). Atelectasis was observed in 12 (46%) and pleural effusion in 11 (42%) patients. CT (n = 6) scans showed peribronchovascular interstitial thickening (n = 6), ground-glass opacities (n = 5), centrilobular nodules (n = 4), consolidation (n = 3), mediastinal lymph node enlargement (n = 5), pleural effusion (n = 3), and pneumomediastinum (n = 3). Abnormal chest radiographs were uncommon in children with a swine-origin influenza A (H1N1) virus (S-OIV) infection. In children, H1N1 virus infection can be included in the differential diagnosis, when chest radiographs and CT scans show prominent peribronchial markings and ill-defined patchy consolidation with mediastinal lymph node enlargement, pleural effusion and pneumomediastinum

  8. Radiology illustrated. Chest radiology

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kyung Soo [Sungkyunkwan Univ. School of Medicine, Seoul (Korea, Republic of). Dept. of Radiology; Han, Joungho [Sungkyunkwan Univ. School of Medicine, Seoul (Korea, Republic of). Dept. of Pathology; Chung, Man Pyo [Sungkyunkwan Univ. School of Medicine, Seoul (Korea, Republic of). Dept. of Medicine; Jeong, Yeon Joo [Pusan National Univ. Hospital, Busan (Korea, Republic of). Dept. of Radiology

    2014-04-01

    Pattern approach to the diagnosis of lung diseases based on CT scan appearances. Guide to quick and reliable differential diagnosis. CT-pathology correlation. Emphasis on state-of-the-art MDCT. The purpose of this atlas is to illustrate how to achieve reliable diagnoses when confronted by the different abnormalities, or ''disease patterns'', that may be visualized on CT scans of the chest. The task of pattern recognition has been greatly facilitated by the advent of multidetector CT (MDCT), and the focus of the book is very much on the role of state-of-the-art MDCT. A wide range of disease patterns and distributions are covered, with emphasis on the typical imaging characteristics of the various focal and diffuse lung diseases. In addition, clinical information relevant to differential diagnosis is provided and the underlying gross and microscopic pathology is depicted, permitting CT-pathology correlation. The entire information relevant to each disease pattern is also tabulated for ease of reference. This book will be an invaluable handy tool that will enable the reader to quickly and easily reach a diagnosis appropriate to the pattern of lung abnormality identified on CT scans.

  9. Improvement of material decomposition and image quality in dual-energy radiography by reducing image noise

    Science.gov (United States)

    Lee, D.; Kim, Y.-s.; Choi, S.; Lee, H.; Choi, S.; Jo, B. D.; Jeon, P.-H.; Kim, H.; Kim, D.; Kim, H.; Kim, H.-J.

    2016-08-01

    Although digital radiography has been widely used for screening human anatomical structures in clinical situations, it has several limitations due to anatomical overlapping. To resolve this problem, dual-energy imaging techniques, which provide a method for decomposing overlying anatomical structures, have been suggested as alternative imaging techniques. Previous studies have reported several dual-energy techniques, each resulting in different image qualities. In this study, we compared three dual-energy techniques: simple log subtraction (SLS), simple smoothing of a high-energy image (SSH), and anti-correlated noise reduction (ACNR) with respect to material thickness quantification and image quality. To evaluate dual-energy radiography, we conducted Monte Carlo simulation and experimental phantom studies. The Geant 4 Application for Tomographic Emission (GATE) v 6.0 and tungsten anode spectral model using interpolation polynomials (TASMIP) codes were used for simulation studies and digital radiography, and human chest phantoms were used for experimental studies. The results of the simulation study showed improved image contrast-to-noise ratio (CNR) and coefficient of variation (COV) values and bone thickness estimation accuracy by applying the ACNR and SSH methods. Furthermore, the chest phantom images showed better image quality with the SSH and ACNR methods compared to the SLS method. In particular, the bone texture characteristics were well-described by applying the SSH and ACNR methods. In conclusion, the SSH and ACNR methods improved the accuracy of material quantification and image quality in dual-energy radiography compared to SLS. Our results can contribute to better diagnostic capabilities of dual-energy images and accurate material quantification in various clinical situations.

  10. Chest radiographic findings of leptospirosis

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Mee Hyun; Jung, Hee Tae; Lee, Young Joong; Yoon, Jong Sup [Hallym University College of Medicine, Seoul (Korea, Republic of)

    1986-04-15

    1. A study on chest radiographic findings of 54 cases with pneumonia like symptoms was performed. Of 54 cases, 8 cases were confirmed to be leptospirosis and 7 cases were leptospirosis combined with Korean hemorrhagic fever. 2. Of 8 cases of leptospirosis, 4 cases showed abnormal chest radiographic findings: acinar nodular type 2, massive confluent consolidation type 2. Of 7 cases of leptospirosis combined with Korean hemorrhagic fever: acinar nodular type 3, massive confluent consolidation type 1, and increased interstitial markings type 1 respectively. 3. It was considered to be difficult to diagnose the leptospirosis on chest radiographic findings alone, especially the case combined with Korean hemorrhagic fever.

  11. CHEST WALL HAMARTOMA : Case Report

    OpenAIRE

    Gülden DİNİZ; Ortaç, Ragıp; Aktaş, Safiye; TEMİR, Günyüz; HOŞGÖR, Münevver; Karaca, İrfan

    2005-01-01

    A case of four-month – old girl diagnosed as chest wall hamartoma is presented. This entity is an extremely rare but characteristic lesion of the ribs usually presenting in the neonate or infant with a mass or respiratory symptoms. Complete sponraneous regression of the lesion has been reported. Recently conservative management of asymptomatic childiren was recommended. Although rare, this condition ought to be kept in mind while dealing with infantile chest wall masses to avoid an errone...

  12. CHEST WALL HAMARTOMA : Case Report

    OpenAIRE

    Gülden DİNİZ; Ortaç, Ragıp; Aktaş, Safiye; HOŞGÖR, Günyüz TEMİR2Münevver; Karaca, İrfan

    2005-01-01

    A case of four-month – old girl diagnosed as chest wall hamartoma is presented. This entity is an extremely rare but characteristic lesion of the ribs usually presenting in the neonate or infant with a mass or respiratory symptoms. Complete sponraneous regression of the lesion has been reported. Recently conservative management of asymptomatic childiren was recommended. Although rare, this condition ought to be kept in mind while dealing with infantile chest wall masses to avoid...

  13. Standard guide for computed radiography

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 This guide provides general tutorial information regarding the fundamental and physical principles of computed radiography (CR), definitions and terminology required to understand the basic CR process. An introduction to some of the limitations that are typically encountered during the establishment of techniques and basic image processing methods are also provided. This guide does not provide specific techniques or acceptance criteria for specific end-user inspection applications. Information presented within this guide may be useful in conjunction with those standards of 1.2. 1.2 CR techniques for general inspection applications may be found in Practice E2033. Technical qualification attributes for CR systems may be found in Practice E2445. Criteria for classification of CR system technical performance levels may be found in Practice E2446. Reference Images Standards E2422, E2660, and E2669 contain digital reference acceptance illustrations. 1.3 The values stated in SI units are to be regarded as the st...

  14. Proton Radiography at Los Alamos

    Energy Technology Data Exchange (ETDEWEB)

    Saunders, Alexander [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-02-28

    The proton radiography (pRad) facility at Los Alamos National Lab uses high energy protons to acquire multiple frame flash radiographic sequences at megahertz speeds: that is, it can make movies of the inside of explosions as they happen. The facility is primarily used to study the damage to and failure of metals subjected to the shock forces of high explosives as well as to study the detonation of the explosives themselves. Applications include improving our understanding of the underlying physical processes that drive the performance of the nuclear weapons in the United States stockpile and developing novel armor technologies in collaboration with the Army Research Lab. The principle and techniques of pRad will be described, and examples of some recent results will be shown.

  15. SU-D-209-06: Study On the Dose Conversion Coefficients in Pediatric Radiography with the Development of Children Voxel Phantoms

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Q [Institute of Radiation Medicine Fudan University, Shanghai (China); Shanghai General Hospital, Shanghai, Shanghai (China); Zhuo, W; Liu, H [Institute of Radiation Medicine Fudan University, Shanghai (China); Liu, Y; Chen, T [Shanghai General Hospital, Shanghai, Shanghai (China)

    2016-06-15

    Purpose: Conversion coefficients of organ dose normalized to entrance skin dose (ESD) are widely used to evaluate the organ doses directly using ESD without time-consuming dose measurement, this work aims to investigate the dose conversion coefficients in pediatric chest and abdomen radiography with the development of 5 years and 10 years old children voxel phantoms. Methods: After segmentation of organs and tissues from CT slice images of ATOM tissue-equivalent phantoms, a 5-year-old and a 10-year-old children computational voxel phantoms were developed for Monte Carlo simulation. The organ doses and the entrance skin dose for pediatric chest postero-anterior projection and abdominal antero-posterior projection were simulated at the same time, and then the organ dose conversion coefficients were calculated.To verify the simulated results, dose measurement was carried out with ATOM tissue-equivalent phantoms for 5 year chest radiography. Results: Simulated results and experimental results matched very well with each other, the result differences of all the organs covered in radiation field were below 16% for 5-year-old child in chest projection. I showed that the conversion coefficients of organs covered in the radiation field were much larger than organs out of the field for all the study cases, for example, the conversion coefficients of stomach, liver intestines, and pancreas are larger for abdomen radiography while conversion coefficients of lungs are larger for chest radiography. Conclusion: The voxel children phantoms were helpful to evaluate the radiation doses more accurately and efficiently. Radiation field was the essential factor that affects the organ dose, use reasonably small field should be encouraged for radiation protection. This work was supported by the National Natural Science Foundation of China(11475047)

  16. Estimation of patient exposure in dental radiography

    Energy Technology Data Exchange (ETDEWEB)

    Yasaki, Shiro; Yukishita, Kentaro; Daibo, Motoji; Suzuki, Yousuke [Ohu Univ., Koriyama, Fukushima (Japan). School of Dentistry

    1998-12-01

    Purpose of this study is to examine comparison of absorbed dose in each mode of newest Multimode Panoramic Radiography and Dental Radiography. The absorbed dose of Dental Radiography uses modified IWAI`s data. The effective doses were calculated using modified tissue weighting factors recommended by International Commission on Radiological Protection (ICRP) in 1990. The result of estimate in effective dose, panoramic auto function mode (4.92 {mu}Sv) was lower than dental full mouth (43.12 {mu}Sv). And clinical effective dose was higher than the other`s modes, in linear tomogram modes. The absorbed dose of patient in Dental Radiography is decreasing in recent years. But in daily clinical work we should pay atteation to justification and optimization. (author)

  17. Single-exposure dual-energy computed radiography.

    Science.gov (United States)

    Stewart, B K; Huang, H K

    1990-01-01

    This paper focuses on analysis and development of a single-exposure dual-energy digital radiographic method using computed radiography (Fuji FCR-101 storage phosphor system). A detector sandwich consisting of storage phosphor imaging plates and an interdetector filter is used. The goal of this process is to provide a simple dual-energy method using typical plane-projection radiographic equipment and techniques. This approach exploits the transparency of the storage phosphor plates, using radiographic information that would be otherwise lost, to provide energy selective information essentially as a by-product of the radiographic examination. In order to effectively make use of the large dynamic range of the storage phosphor imaging plates (10,000:1), a computed radiography image reading mode of fixed analog-to-digital converter gain and variable photomultiplier sensitivity provides image data which can be related to relative incident exposure for export to the decomposition algorithm. Scatter rejection requirements necessitated crossed 12:1 grids for a field size of 36 x 36 cm. Optimal technique parameters obtained from computer simulation through minimization of the aluminum and Plexiglas equivalent image uncertainty under conditions of constant absorbed does resulted as: 100 kVp using a 0.15-mm-thick tin (Sn) interdetector filter for the lung field. This yields a surface exposure of 23 mR and a surface absorbed dose of 0.26 mGy for a 23-cm-thick chest. Clinical application in evaluation of the solitary pulmonary nodule is discussed, along with an image set demonstrating this application.

  18. Imaging beamline for high energy proton radiography

    Institute of Scientific and Technical Information of China (English)

    WEI Tao; YANG Guo-Jun; LONG Ji-Dong; WANG Shao-Heng; HE Xiao-Zhong

    2012-01-01

    Proton radiography is a new tool for advanced hydrotesting.This article will discuss the basic concept of proton radiography first,especially the magnetic lens system.Then a scenario of 50 GeV imaging beamline will be described in every particular,including the matching section,Zumbro lens system and imaging system.The simulation result shows that the scenario of imaging beamline performs well,and the influence of secondary particles can be neglected.

  19. H1N1 influenza infection in children: Frequency, pattern, and outcome of chest radiographic abnormalities

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, S.-Y. [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Kim, J.H., E-mail: jhkate@skku.ed [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Eo, H.; Jeon, T.Y.; Shin, K.E.; Shin, W.S.; Jung, H.N. [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Kim, Y.-J. [Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2011-04-15

    Aim: To describe the frequency, pattern, and outcome of chest radiographic abnormalities in children with H1N1 influenza infection. Materials and methods: Three hundred and fourteen paediatric patients with confirmed H1N1 influenza infection who underwent chest radiography at presentation at a single institution during the outbreak in 2009 were retrospectively reviewed. Abnormal chest radiographic findings related to acute infection were analysed in terms of frequency, pattern, and distribution. Medical records and follow-up radiographs were also reviewed to assess clinical features and outcomes. Results: Chest lesions suggesting acute infection were identified in 49 (16%) patients (mean age 8.2 years, range approximately 1.8-18.5 years). The most common finding was prominent peribronchial marking (71%), followed by air-space opacity (51%) with or without volume decrease, generalized hyperinflation (24%), and pleural effusion (20%). Other minor findings included pneumomediastinum (n = 2) and a nodule (n = 1). Distributions were bilateral (55%) or unilateral (45%) with frequent involvement of lower (78%), and middle (59%) lung zones. Thirty-nine patients (80%) were hospitalized and six (12%) required mechanical ventilation, followed by recovery. Thirty-one out of the 33 patients that underwent follow-up radiography showed marked resolution of all radiographic abnormalities. Conclusion: The frequency of a chest radiographic abnormality was found to be low in children with H1N1 influenza infection. Although typical radiographic findings of a viral lower respiratory infection were more common, unilateral involvement and air-space opacity were common, often with pleural effusion. Furthermore, pulmonary lesions showed near complete resolution on follow-up radiographs in the majority of patients.

  20. Simulation of proton radiography terminal at IMP

    CERN Document Server

    Yan, Yan; Huang, Zhi-Wu; Wang, Jie; Yao, Ze-En; Wang, Jun-Run; Wei, Zheng; Yang, Jian-Cheng; Yuan, You-Jin

    2015-01-01

    Proton radiography is used for advanced hydrotesting as a new type radiography technology due to its powerful penetration capability and high detection efficiency. A new proton radiography terminal will be developed to radiograph static samples at Institute of Modern Physics of Chinese Academy of Science (IMP-CAS). The proton beam with the maximum energy of 2.6 GeV will be produced by Heavy Ion Research Facility in Lanzhou-Cooling Storage Ring (HIRFL-CSR). The proton radiography terminal consists of the matching magnetic lens and the Zumbro lens system. In this paper, the design scheme and all optic parameters of this beam terminal for 2.6GeV proton energy are presented by simulating the beam optics using WINAGILE code. My-BOC code is used to test the particle tracking of proton radiography beam line. Geant4 code and G4beamline code are used for simulating the proton radiography system. The results show that the transmission efficiency of proton without target is 100%, and the effect of secondary particles ca...

  1. Organ Doses and Effective Doses in Pediatric Radiography: Patient-Dose Survey in Finland

    Energy Technology Data Exchange (ETDEWEB)

    Kiljunen, T.; Tietaevaeinen, A.; Parviainen, T.; Viitala, A.; Kortesniemi, M. (Radiation Practices Regulation, Radiation and Nuclear Safety Authority, Helsinki (Finland))

    2009-01-15

    Background: Use of the effective dose in diagnostic radiology permits the radiation exposure of diverse diagnostic procedures to be quantified. Fundamental knowledge of patient doses enhances the implementation of the 'as low as reasonably achievable' (ALARA) principle. Purpose: To provide comparative information on pediatric examination protocols and patient doses in skull, sinus, chest, abdominal, and pelvic radiography examinations. Material and Methods: 24 Finnish hospitals were asked to register pediatric examination data, including patient information and examination parameters and specifications. The total number of examinations in the study was 1916 (1426 chest, 228 sinus, 96 abdominal, 94 skull, and 72 pelvic examinations). Entrance surface dose (ESD) and dose-area products (DAP) were calculated retrospectively or DAP meters were used. Organ doses and effective doses were determined using a Monte Carlo program (PCXMC). Results: There was considerable variation in examination protocols between different hospitals, indicating large variations in patient doses. Mean effective doses of different age groups ranged from 5 muSv to 14 muSv in skull and sinus examinations, from 25 muSv to 483 muSv in abdominal examinations, and from 6 muSv to 48 muSv in chest examinations. Conclusion: In chest and sinus examinations, the amount of data was extensive, allowing national pediatric diagnostic reference levels to be defined. Parameter selection in pediatric examination protocols should be harmonized in order to reduce patient doses and improve optimization

  2. Clinical Factors Associated With Chest Imaging Findings in Hospitalized Infants With Bronchiolitis.

    Science.gov (United States)

    Nazif, Joanne M; Taragin, Benjamin H; Azzarone, Gabriella; Rinke, Michael L; Liewehr, Sheila; Choi, Jaeun; Esteban-Cruciani, Nora

    2017-10-01

    Despite recommendations against routine imaging, chest radiography (CXR) is frequently performed on infants hospitalized for bronchiolitis. We conducted a review of 811 infants hospitalized for bronchiolitis to identify clinical factors associated with imaging findings. CXR was performed on 553 (68%) infants either on presentation or during hospitalization; 466 readings (84%) were normal or consistent with viral illness. Clinical factors significantly associated with normal/viral imaging were normal temperature (odds ratio = 1.66; 95% CI = 1.03-2.67) and normal oxygen saturation (odds ratio = 1.77; 95% CI = 1.1-2.83) on presentation. Afebrile patients with normal oxygen saturations were nearly 3 times as likely to have a normal/viral CXR as patients with both fever and hypoxia. Our findings support the limited role of radiography in the evaluation of hospitalized infants with bronchiolitis, especially patients without fever or hypoxia.

  3. [Chest ultrasonography in pleurapulmonary disease].

    Science.gov (United States)

    Gallego Gómez, M P; García Benedito, P; Pereira Boo, D; Sánchez Pérez, M

    2014-01-01

    Although the initial diagnosis and follow-up of pleuropulmonary disease are normally done with plain chest films and the gold standard for chest disease is computed tomography, diverse studies have established the usefulness of chest ultrasonography in the diagnosis of different pleuropulmonary diseases like pleural effusion and lung consolidation, among others. In this article, we show the different ultrasonographic patterns for pleuropulmonary disease. The availability of ultrasonography in different areas (ICU, recovery areas) makes this technique especially important for critical patients because it obviates the need to transfer the patient. Moreover, ultrasonography is noninvasive and easy to repeat. On the other hand, it enables the direct visualization of pleuropulmonary disease that is necessary for interventional procedures. Copyright © 2011 SERAM. Published by Elsevier Espana. All rights reserved.

  4. Screening for chest disease in college students: policies of student health services regarding the use of routine screening chest radiographs and tuberculin skin tests

    Energy Technology Data Exchange (ETDEWEB)

    Fager, S.S.; Slap, G.B.; Kitz, D.S.; Eisenberg, J.M.

    1984-02-01

    A survey of college health services was conducted to determine their policies regarding the use of screening chest radiographs and tuberculin skin tests. Pre-enrollment chest radiographs are prescribed for all incoming students by 24% of the 531 respondents and for health professions students, foreign students, and intercollegiate athletes only by an additional 20%, 19%, and 6%, respectively. Periodic chest radiography is conducted for all students by 7% of the respondents and for health professions students, foreign students, and intercollegiate athletes only by an additional 22%, 16%, and 8%, respectively. Pre-enrollment tuberculin skin tests are prescribed for all incoming students by 52% of the respondents and for health professions students, foreign students, and intercollegiate athletes only by an additional 48%, 29%, and 9%, respectively. Periodic tuberculin skin testing is conducted for all students by 27% of the respondents and for health professions students, foreign students, and intercollegiate athletes only by an additional 48%, 23%, and 16%, respectively. It is estimated from these data that 723,000 incoming students in the United States received screening chest radiographs in 1979 with estimated charges totaling between $7 million and $27 million. There may be 0.05 to 0.33 induced cases of lung cancer, leukemia, thyroid cancer, and female breast cancer over a 20-year period among this group of students exposed to ionizing radiation.

  5. Contemporary management of flail chest.

    Science.gov (United States)

    Vana, P Geoff; Neubauer, Daniel C; Luchette, Fred A

    2014-06-01

    Thoracic injury is currently the second leading cause of trauma-related death and rib fractures are the most common of these injuries. Flail chest, as defined by fracture of three or more ribs in two or more places, continues to be a clinically challenging problem. The underlying pulmonary contusion with subsequent inflammatory reaction and right-to-left shunting leading to hypoxia continues to result in high mortality for these patients. Surgical stabilization of the fractured ribs remains controversial. We review the history of management for flail chest alone and when combined with pulmonary contusion. Finally, we propose an algorithm for nonoperative and surgical management.

  6. Proton radiography for clinical applications

    Energy Technology Data Exchange (ETDEWEB)

    Talamonti, C., E-mail: cinzia.talamonti@unifi.i [Dipartimento di Fisiopatologia Clinica, Universita degli Studi di Firenze, v.le Morgagni 85, I-50134 Firenze (Italy); INFN, sezione di Firenze, via G. Sansone 1, I-50019 Sesto Fiorentino (Italy); Azienda Ospedaliero-Universitaria Careggi, v.le Morgagni 85, I-50134 Firenze (Italy); Reggioli, V. [Dipartimento di Fisiopatologia Clinica, Universita degli Studi di Firenze, v.le Morgagni 85, I-50134 Firenze (Italy); Bruzzi, M. [INFN, sezione di Firenze, via G. Sansone 1, I-50019 Sesto Fiorentino (Italy); Dipartimento di Energetica, Universita degli Studi di Firenze, via S. Marta 3, I-50139 Firenze (Italy); Bucciolini, M. [Dipartimento di Fisiopatologia Clinica, Universita degli Studi di Firenze, v.le Morgagni 85, I-50134 Firenze (Italy); INFN, sezione di Firenze, via G. Sansone 1, I-50019 Sesto Fiorentino (Italy); Azienda Ospedaliero-Universitaria Careggi, v.le Morgagni 85, I-50134 Firenze (Italy); Civinini, C. [INFN, sezione di Firenze, via G. Sansone 1, I-50019 Sesto Fiorentino (Italy); Marrazzo, L. [Azienda Ospedaliero-Universitaria Careggi, v.le Morgagni 85, I-50134 Firenze (Italy); Menichelli, D. [INFN, sezione di Firenze, via G. Sansone 1, I-50019 Sesto Fiorentino (Finland) (Italy); Dipartimento di Energetica, Universita degli Studi di Firenze, via S. Marta 3, I-50139 Firenze (Italy); Pallotta, S. [Dipartimento di Fisiopatologia Clinica, Universita degli Studi di Firenze, v.le Morgagni 85, I-50134 Firenze (Italy); INFN, sezione di Firenze, via G. Sansone 1, I-50019 Sesto Fiorentino (Italy); Azienda Ospedaliero-Universitaria Careggi, v.le Morgagni 85, I-50134 Firenze (Italy); Randazzo, N. [INFN, sezione di Catania, via S. Sofia 64, I-95123 Catania (Italy); Sipala, V. [INFN, sezione di Catania, via S. Sofia 64, I-95123 Catania (Italy); Dipartimento di Fisica, Universita degli Studi di Catania, via S. Sofia 64, I-95123 Catania (Italy)

    2010-01-11

    Proton imaging is not yet applied as a clinical routine, although its advantages have been demonstrated. In the context of quality assurance in proton therapy, proton images can be used to verify the correct positioning of the patient and to control the range of protons. Proton computed tomography (pCT) is a 3D imaging method appropriate for planning and verification of proton radiation treatments, because it allows evaluating the distributions of proton stopping power within the tissues and can be directly utilized when the patient is in the actual treatment position. The aim of the PRoton IMAging experiment, supported by INFN, and the PRIN 2006 project, supported by MIUR, is to realize a proton computed radiography (pCR) prototype for reconstruction of proton images from a single projection in order to validate the technique with pre-clinical studies and, eventually, to conceive the configuration of a complete pCT system. A preliminary experiment performed at the 250 MeV proton synchrotron of Loma Linda University Medical Center (LLUMC) allowed acquisition of experimental data before the completion of PRIMA project's prototype. In this paper, the results of the LLUMC experiment are reported and the reconstruction of proton images of two phantoms is discussed.

  7. Thorium-uranium fission radiography

    Science.gov (United States)

    Haines, E. L.; Weiss, J. R.; Burnett, D. S.; Woolum, D. S.

    1976-01-01

    Results are described for studies designed to develop routine methods for in-situ measurement of the abundance of Th and U on a microscale in heterogeneous samples, especially rocks, using the secondary high-energy neutron flux developed when the 650 MeV proton beam of an accelerator is stopped in a 42 x 42 cm diam Cu cylinder. Irradiations were performed at three different locations in a rabbit tube in the beam stop area, and thick metal foils of Bi, Th, and natural U as well as polished silicate glasses of known U and Th contents were used as targets and were placed in contact with mica which served as a fission track detector. In many cases both bare and Cd-covered detectors were exposed. The exposed mica samples were etched in 48% HF and the fission tracks counted by conventional transmitted light microscopy. Relative fission cross sections are examined, along with absolute Th track production rates, interaction tracks, and a comparison of measured and calculated fission rates. The practicality of fast neutron radiography revealed by experiments to data is discussed primarily for Th/U measurements, and mixtures of other fissionable nuclei are briefly considered.

  8. Mobile real time radiography system

    Energy Technology Data Exchange (ETDEWEB)

    Vigil, J.; Taggart, D.; Betts, S. [Los Alamos National Lab., NM (United States)] [and others

    1997-11-01

    A 450-keV Mobile Real Time Radiography (RTR) System was delivered to Los Alamos National Laboratory (LANL) in January 1996. It was purchased to inspect containers of radioactive waste produced at (LANL). Since its delivery it has been used to radiograph more than 600 drums of radioactive waste at various LANL sites. It has the capability of inspecting waste containers of various sizes from <1-gal. buckets up to standard waste boxes (SWB, dimensions 54.5 in. x 71 in. x 37 in.). It has three independent x-ray acquisition formats. The primary system used is a 12- in. image intensifier, the second is a 36-in. linear diode array (LDA) and the last is an open system. It is fully self contained with on board generator, HVAC, and a fire suppression system. It is on a 53-ft long x 8-ft. wide x 14-ft. high trailer that can be moved over any highway requiring only an easily obtainable overweight permit because it weights {approximately}38 tons. It was built to conform to industry standards for a cabinet system which does not require an exclusion zone. The fact that this unit is mobile has allowed us to operate where the waste is stored, rather than having to move the waste to a fixed facility.

  9. What is the clinical significance of chest CT when the chest x-ray result is normal in patients with blunt trauma?

    Science.gov (United States)

    Kea, Bory; Gamarallage, Ruwan; Vairamuthu, Hemamalini; Fortman, Jonathan; Lunney, Kevin; Hendey, Gregory W; Rodriguez, Robert M

    2013-08-01

    Computed tomography (CT) has been shown to detect more injuries than plain radiography in patients with blunt trauma, but it is unclear whether these injuries are clinically significant. This study aimed to determine the proportion of patients with normal chest x-ray (CXR) result and injury seen on CT and abnormal initial CXR result and no injury on CT and to characterize the clinical significance of injuries seen on CT as determined by a trauma expert panel. Patients with blunt trauma older than 14 years who received emergency department chest imaging as part of their evaluation at 2 urban level I trauma centers were enrolled. An expert trauma panel a priori classified thoracic injuries and subsequent interventions as major, minor, or no clinical significance. Of 3639 participants, 2848 (78.3%) had CXR alone and 791 (21.7%) had CXR and chest CT. Of 589 patients who had chest CT after a normal CXR result, 483 (82.0% [95% confidence interval [CI], 78.7-84.9%]) had normal CT results, and 106 (18.0% [95% CI, 15.1%-21.3%]) had CTs diagnosing injuries-primarily rib fractures, pulmonary contusion, and incidental pneumothorax. Twelve patients had injuries classified as clinically major (2.0% [95% CI, 1.2%-3.5%]), 78 were clinically minor (13.2% [95% CI, 10.7%-16.2%]), and 16 were clinically insignificant (2.7% (95% CI, 1.7%-4.4%]). Of 202 patients with CXRs suggesting injury, 177 (87.6% [95% CI, 82.4%-91.5%]) had chest CTs confirming injury and 25 (12.4% [95% CI, 8.5%-17.6%]) had no injury on CT. Chest CT after a normal CXR result in patients with blunt trauma detects injuries, but most do not lead to changes in patient management. Copyright © 2013 Elsevier Inc. All rights reserved.

  10. Anatomical decomposition in dual energy chest digital tomosynthesis

    Science.gov (United States)

    Lee, Donghoon; Kim, Ye-seul; Choi, Sunghoon; Lee, Haenghwa; Choi, Seungyeon; Kim, Hee-Joung

    2016-03-01

    Lung cancer is the leading cause of cancer death worldwide and the early diagnosis of lung cancer has recently become more important. For early screening lung cancer, computed tomography (CT) has been used as a gold standard for early diagnosis of lung cancer [1]. The major advantage of CT is that it is not susceptible to the problem of misdiagnosis caused by anatomical overlapping while CT has extremely high radiation dose and cost compared to chest radiography. Chest digital tomosynthesis (CDT) is a recently introduced new modality for lung cancer screening with relatively low radiation dose compared to CT [2] and also showing high sensitivity and specificity to prevent anatomical overlapping occurred in chest radiography. Dual energy material decomposition method has been proposed for better detection of pulmonary nodules as means of reducing the anatomical noise [3]. In this study, possibility of material decomposition in CDT was tested by simulation study and actual experiment using prototype CDT. Furthermore organ absorbed dose and effective dose were compared with single energy CDT. The Gate v6 (Geant4 application for tomographic emission), and TASMIP (Tungsten anode spectral model using the interpolating polynomial) code were used for simulation study and simulated cylinder shape phantom consisted of 4 inner beads which were filled with spine, rib, muscle and lung equivalent materials. The patient dose was estimated by PCXMC 1.5 Monte Carlo simulation tool [4]. The tomosynthesis scan was performed with a linear movement and 21 projection images were obtained over 30 degree of angular range with 1.5° degree of angular interval. The proto type CDT system has same geometry with simulation study and composed of E7869X (Toshiba, Japan) x-ray tube and FDX3543RPW (Toshiba, Japan) detector. The result images showed that reconstructed with dual energy clearly visualize lung filed by removing unnecessary bony structure. Furthermore, dual energy CDT could enhance

  11. A robust neuro-fuzzy classifier for the detection of cardiomegaly in digital chest radiographies

    Directory of Open Access Journals (Sweden)

    Fabián Torres-Robles

    2014-01-01

    Full Text Available Presentamos un nuevo procedimiento que determina de forma automática y fiable la presencia de cardiomegalia en radiografías torácicas. El CTR muestra la relación entre el tamaño del corazón y el tamaño del tórax. El esquema propuesto utiliza un clasificador robusto difuso para encontrar los valores correctos del tamaño del tórax y los límites del corazón derecho e izquierdo para medir el agrandamiento del corazón para detectar cardiomegalia. El método propuesto utiliza operaciones clásicas de morfología para segmentar los pulmones proporcionando baja complejidad computacional y el método difuso propuesto es robusto para encontrar las medidas correctas del CTR proporcionando un cálculo rápido porque las reglas difusas usan operaciones aritméticas elementales para desempeñar una buena detección de cardiomegalia. Finalmente, se mejoran los resultados de clasificación del método difuso propuesto utilizando una red neuronal función de base radial (RBF en términos de precisión, sensibilidad y especificidad.

  12. Progress in electron-multiplying CCD (EMCCD) based high-resolution high-sensitivity x-ray detector for fluoroscopy and radiography

    Science.gov (United States)

    Kuhls, Andrew T.; Yadava, Girijesh; Patel, Vikas; Bednarek, Daniel R.; Rudin, Stephen

    2007-03-01

    A new high-resolution, high-sensitivity, low-noise x-ray detector based on EMCCDs has been developed. The EMCCD detector module consists of a 1kx1k, 8μm pixel EMCCD camera coupled to a CsI(Tl) scintillating phosphor via a fiber optic taper (FOT). Multiple modules can be used to provide the desired field-of-view (FOV). The detector is capable of acquisitions over 30fps. The EMCCD's variable gain of up to 2000x for the pixel signal enables high sensitivity for fluoroscopic applications. With a 3:1 FOT, the detector can operate with a 144μm effective pixel size, comparable to current flat-panel detectors. Higher resolutions of 96 and 48μm pixel size can also be achieved with various binning modes. The detector MTFs and DQEs were calculated using a linear-systems analysis. The zero frequency DQE was calculated to be 59% at 74 kVp. The DQE for the 144μm pixel size was shown to exhibit quantum-noise limited behavior down to ~0.1μR using a conservative 30x gain. At this low exposure, gains above 30x showed limited improvements in DQE suggesting such increased gains may not be necessary. For operation down to 48µm pixel sizes, the detector instrumentation noise equivalent exposure (INEE), defined as the exposure where the instrumentation noise equals the quantum-noise, was flat-panel detectors for applications such as fluoroscopy and angiography requiring high frame rates, resolution, dynamic range and sensitivity while maintaining essentially no lag and very low INEE. Initial images from a prototype detector are also presented.

  13. Application of the Stephan et al. Chest Radiograph Comparison Method to Decomposed Human Remains.

    Science.gov (United States)

    Isa, Mariyam I; Hefner, Joseph T; Markey, Michael A

    2017-09-01

    This manuscript describes the use of comparative radiography of the chest to facilitate positive identification of human remains in advanced stages of decomposition. The method reported by Stephan et al. for positive identification of dry, disarticulated skeletal elements was used on semifleshed, decomposing remains. Positive identification was established through multiple points of concordance observed in radiographs of the left and right clavicles and the C5-T1 vertebrae. This case study demonstrates the applicability of the Stephan et al.'s method in cases involving decomposing remains. © 2017 American Academy of Forensic Sciences.

  14. Screening Performance Characteristic of Ultrasonography and Radiography in Detection of Pleural Effusion; a Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Mahmoud Yousefifard

    2016-01-01

    Full Text Available Introduction: The role of ultrasonography in detection of pleural effusion has long been a subject of interest but controversial results have been reported. Accordingly, this study aims to conduct a systematic review of the available literature on diagnostic value of ultrasonography and radiography in detection of pleural effusion through a meta-analytic approach. Methods: An extended search was done in databases of Medline, EMBASE, ISI Web of Knowledge, Scopus, Cochrane Library, and ProQuest. Two reviewers independently extracted the data and assessed the quality of the articles. Meta-analysis was performed using a mixed-effects binary regression model. Finally, subgroup analysis was carried out in order to find the sources of heterogeneity between the included studies. Results: 12 studies were included in this meta-analysis (1554 subjects, 58.6% male. Pooled sensitivity of ultrasonography in detection of pleural effusion was 0.94 (95% CI: 0.88-0.97; I2= 84.23, p<0.001 and its pooled specificity was calculated to be 0.98 (95% CI: 0.92-1.0; I2= 88.65, p<0.001, while sensitivity and specificity of chest radiography were 0.51 (95% CI: 0.33-0.68; I2= 91.76, p<0.001 and 0.91 (95% CI: 0.68-0.98; I2= 92.86, p<0.001, respectively. Sensitivity of ultrasonography was found to be higher when the procedure was carried out by an intensivist or a radiologist using 5-10 MHz transducers. Conclusion: Chest ultrasonography, as a screening tool, has a higher diagnostic accuracy in identification of plural effusion compared to radiography. The sensitivity of this imaging modality was found to be higher when performed by a radiologist or an intensivist and using 5-10MHz probes.

  15. Development of Prior Image-based, High-Quality, Low-Dose Kilovoltage Cone Beam CT for Use in Adaptive Radiotherapy of Prostate Cancer

    Science.gov (United States)

    2012-05-01

    sagittal (a, c, and e) and middle transverse (b, d, and f) slices reconstructed by use of the expectation maximization (EM, c and d) and FDK (e and f...implemented non- conventional scanning trajectories for the clin- ical CBCT system. The current CBCT systems employ flat -panel detectors, which have limited...patient chest re- gion. The phantom contains both high-contrast structures such as the spine and low-contrast organs such as heart and a soft-tissue tumor

  16. Muon radiography for exploration of Mars geology

    Directory of Open Access Journals (Sweden)

    S. Kedar

    2013-06-01

    Full Text Available Muon radiography is a technique that uses naturally occurring showers of muons (penetrating particles generated by cosmic rays to image the interior of large-scale geological structures in much the same way as standard X-ray radiography is used to image the interior of smaller objects. Recent developments and application of the technique to terrestrial volcanoes have demonstrated that a low-power, passive muon detector can peer deep into geological structures up to several kilometers in size, and provide crisp density profile images of their interior at ten meter scale resolution. Preliminary estimates of muon production on Mars indicate that the near horizontal Martian muon flux, which could be used for muon radiography, is as strong or stronger than that on Earth, making the technique suitable for exploration of numerous high priority geological targets on Mars. The high spatial resolution of muon radiography also makes the technique particularly suited for the discovery and delineation of Martian caverns, the most likely planetary environment for biological activity. As a passive imaging technique, muon radiography uses the perpetually present background cosmic ray radiation as the energy source for probing the interior of structures from the surface of the planet. The passive nature of the measurements provides an opportunity for a low power and low data rate instrument for planetary exploration that could operate as a scientifically valuable primary or secondary instrument in a variety of settings, with minimal impact on the mission's other instruments and operation.

  17. Muon radiography for exploration of Mars geology

    Directory of Open Access Journals (Sweden)

    S. Kedar

    2012-10-01

    Full Text Available Muon radiography is a technique that uses naturally occurring showers of muons (penetrating particles generated by cosmic rays to image the interior of large scale geological structures in much the same way as standard X-ray radiography is used to image the interior of smaller objects. Recent developments and application of the technique to terrestrial volcanoes have demonstrated that a low-power, passive muon detector can peer deep into geological structures up to several kilometers in size, and provide crisp density profile images of their interior at ten meter scale resolution. Preliminary estimates of muon production on Mars indicate that the near horizontal Martian muon flux, which could be used for muon radiography, is as strong or stronger than that on Earth, making the technique suitable for exploration of numerous high priority geological targets on Mars. The high spatial resolution of muon radiography also makes the technique particularly suited for the discovery and delineation of Martian caverns, the most likely planetary environment for biological activity. As a passive imaging technique, muon radiography uses the perpetually present background cosmic ray radiation as the energy source for probing the interior of structures from the surface of the planet. The passive nature of the measurements provides an opportunity for a low power and low data rate instrument for planetary exploration that could operate as a scientifically valuable primary or secondary instrument in a variety of settings, with minimal impact on the mission's other instruments and operation.

  18. [What are the tools for post-occupational follow-up, how should they be performed and what are their performance, limits and benefit/risk ratio? Chest X-Ray and CT scan].

    Science.gov (United States)

    Ferretti, G

    2011-06-01

    Chest radiography and computed tomography (CT) are the two radiological techniques used for the follow-up of people exposed to asbestos. Since the last conference of consensus (1999), the scientific literature has primarily covered high-resolution CT and high-resolution volume CT (HR-VCT). We consider in turn the contribution of digital thoracic radiography, recommendations for the performance of HR-VCT to ensure the quality of examination while controlling the delivered radiation dose, and the need to refer to the "CT atlas of benign diseases related to asbestos exposure", published by a group of French experts in 2007, for interpretation. The results of the published studies concerning radiography or CT are then reviewed. We note the great interobserver variability in the recognition of pleural plaques and asbestosis, indicating the need for adequate training of radiologists, and the importance of defining standardized, quantified criteria for CT abnormalities. The very low agreement between thoracic and general radiologists must be taken into account. The reading of CT scans in cases of occupational exposure to asbestos should be entrusted to thoracic radiologists or to general radiologists having validated specific training. A double interpretation of CT could be considered in medicosocial requests. CT is more sensitive than chest radiography in the detection of bronchial carcinoma but generates a great number of false positive results (96 to 99%). No scientific data are available to assess the role of imaging by either CT or chest radiography in the early detection of mesothelioma.

  19. Diagnosis of vertebral fractures on lateral chest X-ray: Intraobserver agreement of semi-quantitative vertebral fracture assessment

    Energy Technology Data Exchange (ETDEWEB)

    Jagt-Willems, H.C. van der, E-mail: Hvanderjagt@spaarneziekenhuis.nl [Department of Geriatrics, Slotervaart Hospital, Amsterdam (Netherlands); Department of Internal Medicine, Spaarne Hospital, Hoofddorp (Netherlands); Munster, B.C. van [Department of Internal Medicine, Academic Medical Center, Amsterdam (Netherlands); Department of Geriatrics, Gelre Hospitals, Apeldoorn (Netherlands); Leeflang, M. [Department of Geriatrics, Gelre Hospitals, Apeldoorn (Netherlands); Beuerle, E. [Department of Radiology, Slotervaart Hospital, Amsterdam (Netherlands); Tulner, C.R. [Department of Geriatrics, Slotervaart Hospital, Amsterdam (Netherlands); Lems, W.F. [Department of Rheumatology, VU Medical Center, Amsterdam (Netherlands)

    2014-12-15

    Highlights: • (Lateral) chest X-ray's are often performed in older individuals for various reasons. • Vertebral fractures are visualized on lateral chest X-ray, but the diagnosis of vertebral fractures is until now only validated on (lateral) spine X-ray's. • This study shows that a (lateral) chest X-ray is sufficient for the diagnosis of vertebral fractures. • Older individuals with a vertebral fracture on a (lateral) chest X-ray do not need further radiography with thoracic spine X-ray or vertebral fracture assessment with DXA. - Abstract: Background: In clinical practice lateral images of the chest are performed for various reasons. As these lateral chest X rays show the vertebrae of the thoracic and thoraco-lumbar region, we wondered if these X-rays can be used for evaluation of vertebral fractures instead of separate thoracic spine X-rays. Methods: To evaluate the agreement and intraobserver reliability of the semi-quantitative method for vertebral fractures on the lateral chest X-ray (X-chest) in comparison to the lateral thoracic spine X-ray (X-Tspine), two observers scored vertebral fractures on X-Tspine and twice on X-chest, separately, blinded and in different time periods. Agreement and Cohens’ kappa were calculated for a diagnosis of any fracture on patient level and on vertebral body level. The study was done in patients visiting an outpatient geriatric day clinic, with a high prevalence of vertebral fractures. Results: 109 patients were included. The intraobserver agreement for X-chest versus X-Tspine was 95–98% for the two levels of fracturing, with a Cohen's kappa of 0.88–0.91. The intraobserver agreement and reliability of the re-test on the X-chest showed an agreement between 91 and 98% with a Cohen's kappa of 0.81–0.93. More vertebrae were visible on the X-chest, mean 10.2, SD 0.66 versus mean 9.8, SD 0.73 on the X-Tspine (p < 0.001). Conclusion: The results show good agreement and intraobserver reliability on

  20. Recurrent Primary Spontaneous Pneumothorax is Common Following Chest Tube and Conservative Treatment

    DEFF Research Database (Denmark)

    Olesen, Winnie Hedevang; Lindahl-Jacobsen, Rune; Katballe, Niels;

    2016-01-01

    INTRODUCTION: Previous studies on primary spontaneous pneumothorax reported variable recurrence rates, but they were based on heterogeneous patient populations including secondary pneumothorax. We investigated young patients with primary spontaneous pneumothorax exclusively and used a national...... registry to track readmissions and calculate independent predictors of recurrence. METHODS: A prospective cohort study of consecutive young patients who were admitted over a 5-year period with their first episode of primary spontaneous pneumothorax and treated conservatively with a chest tube. Baseline...... characteristics were obtained from questionnaires presented on admittance. All patients were discharged with fully expanded lungs on chest radiography. Patient charts were identified in the national electronic patient registry for detailed information on readmissions due to recurrent spontaneous pneumothorax...

  1. Fifty years of computer analysis in chest imaging: rule-based, machine learning, deep learning.

    Science.gov (United States)

    van Ginneken, Bram

    2017-03-01

    Half a century ago, the term "computer-aided diagnosis" (CAD) was introduced in the scientific literature. Pulmonary imaging, with chest radiography and computed tomography, has always been one of the focus areas in this field. In this study, I describe how machine learning became the dominant technology for tackling CAD in the lungs, generally producing better results than do classical rule-based approaches, and how the field is now rapidly changing: in the last few years, we have seen how even better results can be obtained with deep learning. The key differences among rule-based processing, machine learning, and deep learning are summarized and illustrated for various applications of CAD in the chest.

  2. Effects of angular range on image quality of chest digital tomosynthesis

    Science.gov (United States)

    Lee, Haenghwa; Kim, Ye-seul; Choi, Sunghoon; Lee, Dong-Hoon; Choi, Seungyeon; Kim, Hee-Joung

    2016-03-01

    Chest digital tomosynthesis (CDT) is a new 3D imaging technique that can be expected to improve clinical diagnosis over conventional chest radiography. We investigated the effect of the angular range of data acquisition on the image quality using newly developed CDT system. The four different acquisition sets were studied using +/-15°, +/-20°, +/-30°, and +/-35° angular ranges with 21 projection views (PVs). The point spread function (PSF), modulation transfer function (MTF), artifact spread function (ASF), and normalized contrast-to-noise ratio (CNR) were used to evaluate the image quality. We found that increasing angular ranges improved vertical resolution. The results indicated that there was the opposite relationship of the CNR with angular range for the two tissue types. While CNR for heart tissue increased with increasing angular range, CNR for spine bone decreased. The results showed that the angular range is an important parameter for the CDT exam.

  3. Radiography With the Patient in the centre

    DEFF Research Database (Denmark)

    Møller, Louise

    2016-01-01

    . Several of these elements have a technical focus. There are relations in an MR scan affecting which actions are included in the scan pathway. However, it is the radiographers who decide which actions to include. Patients and radiographers in this study agreed that center in radiography is about directing......The health care system is becoming more technological, and at the same time, it is verbalized that the patient should be in the center. The purpose of this study was to illucidate how radiography with the patient in the center is performed and what patients and radiographers understand about center...... in radiography. Qualitative methods was used; observations of three MR scans and interviews with three patients and three radiographers are discussed. In the description of an MR scan, it appeared that more elements are involved and that each element has a center of equal importance to complete the MR scan...

  4. Thyroid dose distribution in dental radiography

    Energy Technology Data Exchange (ETDEWEB)

    Bristow, R.G.; Wood, R.E.; Clark, G.M. (Ontario Cancer Institute, Toronto (Canada))

    1989-10-01

    The anatomic position and proven radiosensitivity of the thyroid gland make it an organ of concern in dental radiography. A calibrated thermoluminescent dosimetry system was used to investigate the absorbed dose (microGy) to the thyroid gland resultant from a minimum irradiated volume, intraoral full-mouth radiography technique with the use of rectangular collimation with a lead-backed image receptor, and conventional panoramic radiography performed with front and rear lead aprons. Use of the minimum irradiated volume technique resulted in a significantly decreased absorbed dose over the entire thyroid region ranging from 100% to 350% (p less than 0.05). Because this intraoral technique results in radiographs with greater image quality and also exposes the thyroid gland to less radiation than the panoramic, this technique may be an alternative to the panoramic procedure.

  5. The transverse diameter of the chest on routine radiographs reliably estimates gestational age and weight in premature infants

    Energy Technology Data Exchange (ETDEWEB)

    Dietz, Kelly R. [University of Minnesota, Department of Radiology, Minneapolis, MN (United States); Zhang, Lei [University of Minnesota, Biostatistical Design and Analysis Center, Minneapolis, MN (United States); Seidel, Frank G. [Lucile Packard Children' s Hospital, Department of Radiology, Stanford, CA (United States)

    2015-08-15

    Prior to digital radiography it was possible for a radiologist to easily estimate the size of a patient on an analog film. Because variable magnification may be applied at the time of processing an image, it is now more difficult to visually estimate an infant's size on the monitor. Since gestational age and weight significantly impact the differential diagnosis of neonatal diseases and determine the expected size of kidneys or appearance of the brain by MRI or US, this information is useful to a pediatric radiologist. Although this information may be present in the electronic medical record, it is frequently not readily available to the pediatric radiologist at the time of image interpretation. To determine if there was a correlation between gestational age and weight of a premature infant with their transverse chest diameter (rib to rib) on admission chest radiographs. This retrospective study was approved by the institutional review board, which waived informed consent. The maximum transverse chest diameter outer rib to outer rib was measured on admission portable chest radiographs of 464 patients admitted to the neonatal intensive care unit (NICU) during the 2010 calendar year. Regression analysis was used to investigate the association between chest diameter and gestational age/birth weight. Quadratic term of chest diameter was used in the regression model. Chest diameter was statistically significantly associated with both gestational age (P < 0.0001) and birth weight (P < 0.0001). An infant's gestational age and birth weight can be reliably estimated by comparing a simple measurement of the transverse chest diameter on digital chest radiograph with the tables and graphs in our study. (orig.)

  6. Digital radiography: a survey of pediatric dentists.

    Science.gov (United States)

    Russo, Julie M; Russo, James A; Guelmann, Marcio

    2006-01-01

    The purpose of this study was to: (1) determine the popularity of digital radiography among members of the American Academy of Pediatric Dentistry (AAPD); and (2) report the most common systems in use. An AAPD-approved, voluntary, and anonymous electronic survey was developed and sent to 923 board certified pediatric dentists. Years in practice and in-office x-ray technology (digital or conventional) were inquired about initially. If negative for the use of digital radiography, future consideration for converting to digital radiography was ascertained. For positive responses, more in-depth information was requested. Information on type of system (sensor or phosphor plate), user friendliness, diagnostic ability, patient's comfort, general costs, durability, and parental and overall satisfaction was collected. For most of the questions, a 5-point assessment scale was used. Opportunity for additional comments was provided upon survey completion. Data was analyzed using descriptive statistics. A 32% (296/923) response rate was obtained. Twenty-six percent of practitioners (78/296) implemented digital radiography in their practices, whereas 71% considered future acquisition. Similar distribution for sensor and phosphor plate users was found. Sensor technology was reported to produce faster images, but was less tolerable by young children due to size and thickness. Phosphor plates were considered more children friendly, less expensive, and less durable. Parental satisfaction was very high with great marketing value. Picture quality was comparable to conventional film. Overall, digital radiography users would recommend it to other pediatric dentists. Digital radiography is not yet popular among pediatric dentists. Cost reduction and technology advancement may enhance utilization.

  7. Proton Radiography: Its uses and Resolution Scaling

    Energy Technology Data Exchange (ETDEWEB)

    Mariam, Fesseha G. [Los Alamos National Laboratory

    2012-08-09

    Los Alamos National Laboratory has used high energy protons as a probe in flash radiography for over a decade. In this time the proton radiography project has used 800 MeV protons, provided by the LANSCE accelerator facility at LANL, to diagnose over five-hundred dynamic experiments in support of stockpile stewardship programs as well as basic materials science. Through this effort significant experience has been gained in using charged particles as direct radiographic probes to diagnose transient systems. The results of this experience will be discussed through the presentation of data from experiments recently performed at the LANL pRad.

  8. Statistical Uncertainty in Quantitative Neutron Radiography

    CERN Document Server

    Piegsa, Florian M

    2016-01-01

    We demonstrate a novel procedure to calibrate neutron detection systems commonly used in standard neutron radiography. This calibration allows determining the uncertainties due to Poisson-like neutron counting statistics for each individual pixel of a radiographic image. The obtained statistical errors are necessary in order to perform correct quantitative analysis. This fast and convenient method is applied to real data measured at the cold neutron radiography facility ICON at the Paul Scherrer Institute. Moreover, from the results the effective neutron flux at the beam line is determined.

  9. Chest physiotherapy compared to no chest physiotherapy for cystic fibrosis.

    Science.gov (United States)

    Warnock, Louise; Gates, Alison

    2015-12-21

    Chest physiotherapy is widely used in people with cystic fibrosis in order to clear mucus from the airways. This is an updated version of previously published reviews. To determine the effectiveness and acceptability of chest physiotherapy compared to no treatment or spontaneous cough alone to improve mucus clearance in cystic fibrosis. We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register which comprises references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings.Date of the most recent search of the Group's Cystic Fibrosis Trials Register: 02 June 2015. Randomised or quasi-randomised clinical studies in which a form of chest physiotherapy (airway clearance technique) were taken for consideration in people with cystic fibrosis compared with either no physiotherapy treatment or spontaneous cough alone. Both authors independently assessed study eligibility, extracted data and assessed the risk of bias in the included studies. There was heterogeneity in the published outcomes, with variable reporting which meant pooling of the data for meta-analysis was not possible. The searches identified 157 studies, of which eight cross-over studies (data from 96 participants) met the inclusion criteria. There were differences between studies in the way that interventions were delivered, with several of the intervention groups combining more than one treatment modality. One included study looked at autogenic drainage, six considered conventional chest physiotherapy, three considered oscillating positive expiratory pressure, seven considered positive expiratory pressure and one considered high pressure positive expiratory pressure. Of the eight studies, six were single-treatment studies and in two, the treatment intervention was performed over two consecutive days (once daily in one, twice daily in the other). This enormous heterogeneity in the treatment

  10. Actinomycosis - Left Post Chest Wall

    Directory of Open Access Journals (Sweden)

    Kafil Akhtar, M. Naim, S. Shamshad Ahmad, Nazoora Khan, Uroos Abedi, A.H. Khan*

    2008-01-01

    Full Text Available A forty year old female of weak body built presented with recurring small hard lumps in let posteriorchest wall for 3 years and discharging ulcers for 3 months duration. Clinically, the provisional diagnosiswas malignancy with secondary infection. FNAC showed features suggestive of dysplasia buthistopathology confirmed the diagnosis as actinomycosis. The present case is reported due to rare incidenceof actinomycosis at post chest wall with muscle involvement.

  11. Fully automatic lung segmentation and rib suppression methods to improve nodule detection in chest radiographs.

    Science.gov (United States)

    Soleymanpour, Elaheh; Pourreza, Hamid Reza; Ansaripour, Emad; Yazdi, Mehri Sadooghi

    2011-07-01

    Computer-aided Diagnosis (CAD) systems can assist radiologists in several diagnostic tasks. Lung segmentation is one of the mandatory steps for initial detection of lung cancer in Posterior-Anterior chest radiographs. On the other hand, many CAD schemes in projection chest radiography may benefit from the suppression of the bony structures that overlay the lung fields, e.g. ribs. The original images are enhanced by an adaptive contrast equalization and non-linear filtering. Then an initial estimation of lung area is obtained based on morphological operations and then it is improved by growing this region to find the accurate final contour, then for rib suppression, we use oriented spatial Gabor filter. The proposed method was tested on a publicly available database of 247 chest radiographs. Results show that this method outperformed greatly with accuracy of 96.25% for lung segmentation, also we will show improving the conspicuity of lung nodules by rib suppression with local nodule contrast measures. Because there is no additional radiation exposure or specialized equipment required, it could also be applied to bedside portable chest x-rays. In addition to simplicity of these fully automatic methods, lung segmentation and rib suppression algorithms are performed accurately with low computation time and robustness to noise because of the suitable enhancement procedure.

  12. Simple pulmonary eosinophilia (loeffler's syndrome): chest radiographic and CT findings

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Kyung Jae; Lee, Kyung Soo; Kim, Tae Sung; Chung, Man Pyo; Choi, Dong Chull; Kwon, O Jung [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2000-01-01

    The purpose of our study is to describe the chest radiographic and CT findings of simple pulmonary eosinophilia. Twenty-six patients with simple pulmonary eosinophilia underwent chest radiography and CT scanning; the results were analyzed retrospectively by two chest radiologists, focusing on the patterns and distribution of the parenchymal abnormalities. The chest radiographs were normal in eight patients (31%), while among the remaining 18 patients, they showed subtle opacity (n=3D9), nodules (n=3D8), consolidation (n=3D2), and mass (n=3D1). Follow-up chest radiographs (m=3D18) demonstrated complete (n=3D16) or partial (n=3D1) resolution of parenchymal lesions or migratory lesions (n=3D1). On CT, nodule(s) (n=3D19) were most commonly seen, followed by ground-glass opacity (n=3D16), consolidation (n=3D3), and mass (n=3D1). A peripheral halo surrounding a nodule or an area of consolidation was seen in 18 patients. The nodules(s) (n=3D19) were subpleural (n=3D13) or random (=3D6). Areas of ground-glass opacity (n=3D16) were subpleural (n=3D13), random (n=3D2), or central (n=3D1). All lesions were patchy rather than diffuse. Follow-up CT in nine patients showed complete (n=3D7) or partial (n=3D2) resolution of parenchymal lesions. Chest radiographs of patients with simple pulmonary eosinophilia often reveal no abnormality. The most common finding is subtle opacity or nodule(s), while CT reveals transient nodule(s) with a surrounding halo or transient areas of ground glass opacity. (author)

  13. Feline dental radiography and radiology: A primer.

    Science.gov (United States)

    Niemiec, Brook A

    2014-11-01

    Information crucial to the diagnosis and treatment of feline oral diseases can be ascertained using dental radiography and the inclusion of this technology has been shown to be the best way to improve a dental practice. Becoming familar with the techniques required for dental radiology and radiography can, therefore, be greatly beneficial. Novices to dental radiography may need some time to adjust and become comfortable with the techniques. If using dental radiographic film, the generally recommended 'E' or 'F' speeds may be frustrating at first, due to their more specific exposure and image development requirements. Although interpreting dental radiographs is similar to interpreting a standard bony radiograph, there are pathologic states that are unique to the oral cavity and several normal anatomic structures that may mimic pathologic changes. Determining which teeth have been imaged also requires a firm knowledge of oral anatomy as well as the architecture of dental films/digital systems. This article draws on a range of dental radiography and radiology resources, and the benefit of the author's own experience, to review the basics of taking and interpreting intraoral dental radiographs. A simplified method for positioning the tubehead is explained and classic examples of some common oral pathologies are provided. © ISFM and AAFP 2014.

  14. Establishing rigour in qualitative radiography research

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, F.J. [School of Healthcare Professions, University of Salford, Salford M6 6PU (United Kingdom)], E-mail: f.j.murphy@salford.ac.uk; Yielder, J. [Medical Imaging, School of Health Sciences, Unitec, Auckland (New Zealand)

    2010-02-15

    The vast majority of radiography research is subject to critique and evaluation from peers in order to justify the method and the outcome of the study. Within the quantitative domain, which the majority of medical imaging publications tend to fall into, there are prescribed methods for establishing scientific rigour and quality in order to critique a study. However, researchers within the qualitative paradigm, which is a developing area of radiography research, are often unclear about the most appropriate methods to measure the rigour (standards and quality) of a research study. This article considers the issues related to rigour, reliability and validity within qualitative research. The concepts of reliability and validity are briefly discussed within traditional positivism and then the attempts to use these terms as a measure of quality within qualitative research are explored. Alternative methods for research rigour in interpretive research (meanings and emotions) are suggested in order to compliment the existing radiography framework that exists for qualitative studies. The authors propose the use of an established model that is adapted to reflect the iterative process of qualitative research. Although a mechanistic approach to establishing rigour is rejected by many qualitative researchers, it is argued that a guide for novice researchers within a developing research base such as radiography is appropriate in order to establish the credibility and trustworthiness of a qualitative study.

  15. Safety Testing of Industrial Radiography Devices

    Energy Technology Data Exchange (ETDEWEB)

    Trapp, D.J.

    1999-09-29

    The Nuclear Regulatory Commission contracted the Savannah River Technology Center to verify the relevancy of the 10 CFR Part 34 requirements for the normal use of portable gamma radiography systems and to propose recommendations for changes or modifications to the requirements.

  16. Radiography Student Participation in Professional Organizations.

    Science.gov (United States)

    Michael, Kimberly; Tran, Xuan; Keller, Shelby; Sayles, Harlan; Custer, Tanya

    2017-09-01

    To gather data on educational program requirements for student membership in a state or national professional society, organization, or association. A 10-question online survey about student involvement in professional societies was emailed to 616 directors of Joint Review Committee on Education in Radiologic Technology (JRCERT)-accredited radiography programs. A total of 219 responses were received, for a 36% response rate. Of these, 89 respondents (41%) answered that their programs require students to join a professional organization. The society respondents most often required (70%) was a state radiography society. Sixty respondents (68%) answered that students join a society at the beginning of the radiography program (from matriculation to 3 months in). Of programs requiring student membership in professional societies, 42 (49%) reported that their students attend the state or national society annual conference; however, participation in activities at the conferences and in the society throughout the year is lower than conference attendance. Some directors stated that although their programs' policies do not allow membership mandates, they encourage students to become members, primarily so that they can access webinars and other educational materials or information related to the profession. Survey data showed that most JRCERT-accredited radiography programs support but do not require student membership in professional organizations. The data reveal that more programs have added those requirements in recent years. Increased student participation could be realized if programs mandated membership and supported it financially. ©2017 American Society of Radiologic Technologists.

  17. INDUSTRIAL RADIOGRAPHY COURSE, INSTRUCTORS' GUIDE. VOLUME 2.

    Science.gov (United States)

    Texas A and M Univ., College Station. Engineering Extension Service.

    INFORMATION RELATIVE TO THE LESSON PLANS IN "INDUSTRIAL RADIOGRAPHY COURSE, INSTRUCTOR'S GUIDE, VOLUME I" (VT 003 565) IS PRESENTED ON 52 INFORMATION SHEETS INCLUDING THE SUBJECTS SHIELDING EQUATIONS AND LOGARITHMS, METAL PROPERTIES, FIELD TRIP INSTRUCTIONS FOR STUDENTS, WELDING SYMBOLS AND SIZES, SAMPLE REPORT FORMS, AND TYPICAL SHIPPING…

  18. Conditions for radiation protection in industrial radiography

    CERN Document Server

    1999-01-01

    The leaflet specifies radiation protection requirements for industrial radiography in Norway. The regulations are directed towards companies using or distributing sealed radioactive sources, x-ray equipment or accelerators in non-destructive material testing (NDT). Technical requirements to the equipment, as well as administrative requirements for use, licensing, qualifications, handling of accidents etc. are given. (Author)

  19. Comprehensive Optimization Process of Paranasal Sinus Radiography

    Energy Technology Data Exchange (ETDEWEB)

    Saarakkala, S. (Dept. of Clinical Radiology, Kuopio Univ. Hospital, Kuopio (Finland)); Nironen, K.; Hermunen, H.; Aarnio, J.; Heikkinen, J.O. (Dept. of Radiology, Etel-Savo Hospital District, Mikkeli Central Hospital, Mikkeli (Finland))

    2009-04-15

    Background: The optimization of radiological examinations is important in order to reduce unnecessary patient radiation exposure. Purpose: To perform a comprehensive optimization process for paranasal sinus radiography at Mikkeli Central Hospital (Finland). Material and Methods: Patients with suspicion of acute sinusitis were imaged with a Kodak computed radiography (CR) system (n=20) and with a Philips digital radiography (DR) system (n=30) using focus-detector distances (FDDs) of 110 cm, 150 cm, or 200 cm. Patients' radiation exposure was determined in terms of entrance surface dose and dose-area product. Furthermore, an anatomical phantom was used for the estimation of point doses inside the head. Clinical image quality was evaluated by an experienced radiologist, and physical image quality was evaluated from the digital radiography phantom. Results: Patient doses were significantly lower and image quality better with the DR system compared to the CR system. The differences in patient dose and physical image quality were small with varying FDD. Clinical image quality of the DR system was lowest with FDD of 200 cm. Further, imaging with FDD of 150 cm was technically easier for the technologist to perform than with FDD of 110 cm. Conclusion: After optimization, it was recommended that the DR system with FDD of 150 cm should always be used at Mikkeli Central Hospital. We recommend this kind of comprehensive approach in all optimization processes of radiological examinations.

  20. The role of whole body spiral CT in the primary work-up of polytrauma patients - comparison with conventional radiography and abdominal sonography; Die Rolle der Ganzkoerper-Spiral-CT bei der Primaerdiagnostik polytraumatisierter Patienten - Vergleich mit konventioneller Radiographie und Abdomensonographie

    Energy Technology Data Exchange (ETDEWEB)

    Albrecht, T.; Schlippenbach, J. von; Wolf, K.J. [Klinik und Poliklinik fuer Radiologie und Nuklearmedizin, Charite - Campus Benjamin Franklin (Germany); Stahel, P.F.; Ertel, W. [Klinik fuer Unfall- und Wiederherstellungschirurgie, Charite - Campus Benjamin Franklin (Germany)

    2004-08-01

    Purpose: To evaluate the role of routine 'whole body spiral CT' in the primary work-up of polytrauma patients for injuries of the thorax, abdomen and spine, and to compare the results with those of conventional radiography of the chest and spine and abdominal ultrasound. Materials and Methods: Fifty consecutive polytrauma patients underwent contrast-enhanced single slice spiral CT (5 mm collimation) from the vertex to the floor of the pelvis as part of the primary work-up after emergency room admission. Overlapping high resolution sections and sagittal reformations of the spine were obtained. Reports of additional chest radiographs (n=43), abdominal ultrasound examinations (n=47) and spine radiographs (n=36) performed in the emergency room were available for retrospective comparison. The 'final diagnoses', which served as the standard of reference, were taken from the patients' records using all information that became available until discharge or death, such as findings from further imaging, surgery and autopsy. Results: CT showed 109 (97%) of 112 thoracic and abdominal soft-tissue injuries. Relevant injuries missed were an early splenic laceration and an early pelvic hematoma, both of which became clinically apparent several hours later. There were 4 false positive CT findings. Conventional chest radiography demonstrated only 20% of thoracic and sonography 22% of abdominal injuries. Chest radiography and sonography produced 2 false-positive findings each. CT showed 66 (87%) of 76 vertebral fractures including all 19 unstable ones. CT missed 5 anterior vertebral body and 5 spinous/transverse process fractures. Conventional radiography found 71% of vertebral fractures including only 50% of the unstable one. (orig.)

  1. MRI versus radiography of acromioclavicular joint dislocation.

    Science.gov (United States)

    Nemec, Ursula; Oberleitner, Gerhard; Nemec, Stefan F; Gruber, Michael; Weber, Michael; Czerny, Christian; Krestan, Christian R

    2011-10-01

    Acromioclavicular joint injuries are usually diagnosed by clinical and radiographic assessment with the Rockwood classification, which is crucial for treatment planning. In view of the implementation of MRI for visualization of the acromioclavicular joint, the purpose of this study was to describe the MRI findings of acromioclavicular joint dislocation in comparison with the radiographic findings. Forty-four patients with suspected unilateral acromioclavicular joint dislocation after acute trauma were enrolled in this prospective study. All patients underwent digital radiography and 1-T MRI with a surface phased-array coil. MRI included coronal proton density-weighted turbo spin-echo and coronal 3D T1-weighted fast field-echo water-selective sequences. The Rockwood classification was used to assess acromioclavicular joint injuries at radiography and MRI. An adapted Rockwood classification was used for MRI evaluation of the acromioclavicular joint ligaments. The classifications of acromioclavicular joint dislocations diagnosed with radiography and MRI were compared. Among 44 patients with Rockwood type I-IV injuries on radiographs, classification on radiographs and MR images was concordant in 23 (52.2%) patients. At MRI, the injury was reclassified to a less severe type in 16 (36.4%) patients and to a more severe type in five (11.4%) patients. Compared with the findings according to the original Rockwood system, with the adapted system that included MRI findings, additional ligamentous lesions were found in 11 (25%) patients. In a considerable number of patients, the MRI findings change the Rockwood type determined with radiography. In addition to clinical assessment and radiography, MRI may yield important findings on ligaments that may influence management.

  2. CARDIOVASCULAR DISORDERS IN ADOLESCENTS WITH CHEST PAIN

    Directory of Open Access Journals (Sweden)

    Sri Endah Rahayuningsih

    2014-06-01

    Full Text Available Objective: To detect cardiovascular abnormalities in adolescents with chest pain. Methods: In this cross sectional study, the subjects were 25 adolescents with chest pain who came to the Cardiac Center of Dr. Hasan Sadikin General Hospital, Bandung during the period of January 2008 to January 2011. The presence of established cardiovascular disorders were based on history, physical examination, electrocardiography and echocardiography Results: It was found that 13/25 adolescents with chest pain had cardiovascular abnormalities. Of the 25 teens that came with chest pain, most of which showed normal electrocardiographic results, only 9/25 of those with dysrhythmias experienced sinus tachycardia and 8 had a first degree AV block. Echocardiography examination showed only four patients with abnormal cardiac anatomy. No correlation between nutritional status and chest pain, and cardiovascular abnormalities and chest pain (p=0.206 and p=0.632, respectively. There was a positive correlation between sex and cardiovascular abnormalities in adolescents with chest pain (p=0.007. Chest pain is a prevalent problem that is usually benign and that it frequently signals underlying cardiac disease. Conclusions: Cardiovascular abnormalities in adolescents with symptoms of chest pain are found in some cases. There is no correlation between female and male adolescents with chest pain and cardiovascular abnormalities.

  3. Flail chest and pulmonary contusion.

    Science.gov (United States)

    Bastos, Renata; Calhoon, John H; Baisden, Clinton E

    2008-01-01

    Flail chest is most often accompanied by a significant underlying pulmonary parenchymal injury and can be a life-threatening thoracic injury. Its management is often complicated by the other injuries it is frequently associated with. Similarly, mortality and morbidity are dictated most often by the associated injuries and findings. Its treatment is complex and should first be one of pain management, judicious fluid resuscitation, and excellent pulmonary toilet. In those patients requiring mechanical ventilatory support, or who require ipsilateral thoracocotomy, rib stabilization may be considered depending on a host of potentially conflicting indications and contraindications. At the end of this section are listed the current major recommendations and their levels of evidence.

  4. Chest neoplasms with infectious etiologies.

    Science.gov (United States)

    Restrepo, Carlos S; Chen, Melissa M; Martinez-Jimenez, Santiago; Carrillo, Jorge; Restrepo, Catalina

    2011-12-28

    A wide spectrum of thoracic tumors have known or suspected viral etiologies. Oncogenic viruses can be classified by the type of genomic material they contain. Neoplastic conditions found to have viral etiologies include post-transplant lymphoproliferative disease, lymphoid granulomatosis, Kaposi's sarcoma, Castleman's disease, recurrent respiratory papillomatosis, lung cancer, malignant mesothelioma, leukemia and lymphomas. Viruses involved in these conditions include Epstein-Barr virus, human herpes virus 8, human papillomavirus, Simian virus 40, human immunodeficiency virus, and Human T-lymphotropic virus. Imaging findings, epidemiology and mechanism of transmission for these diseases are reviewed in detail to gain a more thorough appreciation of disease pathophysiology for the chest radiologist.

  5. Image quality and exposure dose in digital projection radiography; Bildqualitaet und Dosis in der Digitalen Projektionsradiographie

    Energy Technology Data Exchange (ETDEWEB)

    Busch, H.P.; Busch, S.; Decker, C.; Schilz, C. [Krankenhaus der Barmherzigen Brueder Trier, Abt. fuer Radiologie, Trier (Germany)

    2003-01-01

    Purpose: Comparison of the imaging capabilities of storage phosphor (computed) radiography and flat plate radiography with conventional film-screen radiography to find new strategies for quality and dose management, i.e., optimizing imaging quality and dose depending on the imaging method and clinical situation. Materials and Methods: Images of a CDRAD-phantom, hand-phantom, abdomen-phantom and chest-phantom obtained with different exposure voltages (50 kV, 73 kV, 109 kV) and different speeds (200, 400, 800, 1600) were processed with various digital systems (flat plate detector: Digital Diagnost [Philips]; storage phosphors: ADC-70 [Agfa], ADC-Solo [Agfa], FCR XG 1 [Fuji]) and a conventional film-screen system (HT100G/Ortho Regular [Agfa]). Results: The evaluation of CDRAD images found the flat plate detector system to have the highest contrast detectability for all dose levels, followed by the FCR XG 1, ADC-Solo and ADC-70 systems. Comparison of the organ-phantom images found the flat plate detector system to be equal to film-screen radiography and especially to storage phosphor systems even for low exposure doses. Conclusions: Flat plate radiography systems demonstrate the highest potential for high image quality when reducing the exposure dose. Depending on the system generation, the storage phosphor systems also show an improved image quality, but the possibility of a dose reduction is limited in comparison with the flat plate detector system. (orig.) [German] Ziel: Die vergleichende Darstellung der Abbildungseigenschaften verschiedener Speicherfoliengeraete und einer Flachdetektoranlage mit Film/Folienaufnahmen kann zu neuen Strategien des Qualitaets- und Dosismanagements fuehren, d.h. zu einer Optimierung von Bildqualitaet und Dosis in Abhaengigkeit von der Untersuchungsmethode und der klinischen Fragestellung. Methode: Aufnahmen von einem CDRAD-Phantom, Handphantom, Abdomenphantom und Thoraxphantom wurden mit verschiedenen digitalen Systemen (Flachdetektor

  6. Technique for chest compressions in adult CPR

    Directory of Open Access Journals (Sweden)

    Rajab Taufiek K

    2011-12-01

    Full Text Available Abstract Chest compressions have saved the lives of countless patients in cardiac arrest as they generate a small but critical amount of blood flow to the heart and brain. This is achieved by direct cardiac massage as well as a thoracic pump mechanism. In order to optimize blood flow excellent chest compression technique is critical. Thus, the quality of the delivered chest compressions is a pivotal determinant of successful resuscitation. If a patient is found unresponsive without a definite pulse or normal breathing then the responder should assume that this patient is in cardiac arrest, activate the emergency response system and immediately start chest compressions. Contra-indications to starting chest compressions include a valid Do Not Attempt Resuscitation Order. Optimal technique for adult chest compressions includes positioning the patient supine, and pushing hard and fast over the center of the chest with the outstretched arms perpendicular to the patient's chest. The rate should be at least 100 compressions per minute and any interruptions should be minimized to achieve a minimum of 60 actually delivered compressions per minute. Aggressive rotation of compressors prevents decline of chest compression quality due to fatigue. Chest compressions are terminated following return of spontaneous circulation. Unconscious patients with normal breathing are placed in the recovery position. If there is no return of spontaneous circulation, then the decision to terminate chest compressions is based on the clinical judgment that the patient's cardiac arrest is unresponsive to treatment. Finally, it is important that family and patients' loved ones who witness chest compressions be treated with consideration and sensitivity.

  7. Anterior chest wall examination reviewed

    Directory of Open Access Journals (Sweden)

    F. Trotta

    2011-09-01

    Full Text Available Anterior chest wall involvement is not infrequently observed within inflammatory arthropaties, particularly if one considers seronegative spondiloarthritides and SAPHO syndrome. Physical examination is unreliable and conventional X-rays analysis is an unsatisfactory tool during diagnostic work-up of this region. Scintigraphic techniques yield informations both on the activity and on the anatomical extent of the disease while computerized tomography visualize the elementary lesions, such as erosions, which characterize the process. Moreover, when available, magnetic resonance imaging couple the ability to finely visualize such lesions with the possibility to show early alterations and to characterize the “activity” of the disease, presenting itself as a powerful tool both for diagnosis and follow-up. This review briefly shows the applications of imaging techniques for the evaluation of the anterior chest wall focusing on what has been done in the SAPHO syndrome which can be considered prototypical for this regional involvement since it is the osteo-articular target mainly affected by the disease.

  8. Relevant surgical anatomy of the chest wall.

    Science.gov (United States)

    Naidu, Babu V; Rajesh, Pala B

    2010-11-01

    The chest wall, like other regional anatomy, is a remarkable fusion of form and function. Principal functions are the protection of internal viscera and an expandable cylinder facilitating variable gas flow into the lungs. Knowledge of the anatomy of the whole cylinder (ribs, sternum, vertebra, diaphragm, intercostal spaces, and extrathoracic muscles) is therefore not only important in the local environment of a specific chest wall resection but also in its relation to overall function. An understanding of chest wall kinematics might help define the loss of function after resection and the effects of various chest wall substitutes. Therefore, this article is not an exhaustive anatomic description but a focused summary and discussion.

  9. Potential of ultrasound in the pediatric chest

    Energy Technology Data Exchange (ETDEWEB)

    Trinavarat, Panruethai, E-mail: pantrinavarat@hotmail.com [Department of Radiology, Faculty of Medicine, Chulalongkorn University, Rama IV Road, Pathumwan, Bangkok 10330 (Thailand); Riccabona, Michael, E-mail: michael.riccabona@klinikum-graz.at [Department of Radiology, Division of Pediatric Radiology, University Hospital Graz (Austria)

    2014-09-15

    Ultrasound (US) of chest, even with inherent limitations of the US beam and air, has been useful in many pediatric chest conditions. It has extended its role and is now widely used by many subspecialists in medicine. This review article will cover techniques, indications, and applications of chest US in neonates, infants and children, including also different common as well as some rare and modern aspects and applications, such as pleural effusion, pneumothorax, pulmonary lesions, mediastinum, diaphragm, and chest wall. Other related imaging modalities are also briefly discussed.

  10. Potential of ultrasound in the pediatric chest.

    Science.gov (United States)

    Trinavarat, Panruethai; Riccabona, Michael

    2014-09-01

    Ultrasound (US) of chest, even with inherent limitations of the US beam and air, has been useful in many pediatric chest conditions. It has extended its role and is now widely used by many subspecialists in medicine. This review article will cover techniques, indications, and applications of chest US in neonates, infants and children, including also different common as well as some rare and modern aspects and applications, such as pleural effusion, pneumothorax, pulmonary lesions, mediastinum, diaphragm, and chest wall. Other related imaging modalities are also briefly discussed.

  11. Development of a mini-mobile digital radiography system by using wireless smart devices.

    Science.gov (United States)

    Jeong, Chang-Won; Joo, Su-Chong; Ryu, Jong-Hyun; Lee, Jinseok; Kim, Kyong-Woo; Yoon, Kwon-Ha

    2014-08-01

    The current technologies that trend in digital radiology (DR) are toward systems using portable smart mobile as patient-centered care. We aimed to develop a mini-mobile DR system by using smart devices for wireless connection into medical information systems. We developed a mini-mobile DR system consisting of an X-ray source and a Complementary Metal-Oxide Semiconductor (CMOS) sensor based on a flat panel detector for small-field diagnostics in patients. It is used instead of the systems that are difficult to perform with a fixed traditional device. We also designed a method for embedded systems in the development of portable DR systems. The external interface used the fast and stable IEEE 802.11n wireless protocol, and we adapted the device for connections with Picture Archiving and Communication System (PACS) and smart devices. The smart device could display images on an external monitor other than the monitor in the DR system. The communication modules, main control board, and external interface supporting smart devices were implemented. Further, a smart viewer based on the external interface was developed to display image files on various smart devices. In addition, the advantage of operators is to reduce radiation dose when using remote smart devices. It is integrated with smart devices that can provide X-ray imaging services anywhere. With this technology, it can permit image observation on a smart device from a remote location by connecting to the external interface. We evaluated the response time of the mini-mobile DR system to compare to mobile PACS. The experimental results show that our system outperforms conventional mobile PACS in this regard.

  12. Flat-Panel Computed Tomography (DYNA-CT) in Neuroradiology. From High-Resolution Imaging of Implants to One-Stop-Shopping for Acute Stroke.

    Science.gov (United States)

    Doerfler, A; Gölitz, P; Engelhorn, T; Kloska, S; Struffert, T

    2015-10-01

    Originally aimed at improving standard radiography by providing higher absorption efficiency and a wider dynamic range, flat-panel detector technology has meanwhile got widely accepted in the neuroradiological community. Especially flat-panel detector computed tomography (FD-CT) using rotational C-arm mounted flat-panel detector technology is capable of volumetric imaging with a high spatial resolution. By providing CT-like images of the brain within the angio suite, FD-CT is able to rapidly visualize hemorrhage and may thus improve complication management without the need of patient transfer. As "Angiographic CT" FD-CT may be helpful during many diagnostic and neurointerventional procedures and for noninvasive monitoring and follow-up. In addition, spinal interventions and high-resolution imaging of the temporal bone might also benefit from FD-CT. Finally, using novel dynamic perfusion and angiographic protocols, FD-CT may provide functional information on brain perfusion and vasculature with the potential to replace standard imaging in selected acute stroke patients.

  13. Rotational flat-panel computed tomography in diagnostic and interventional neuroradiology

    Energy Technology Data Exchange (ETDEWEB)

    Doerfler, A.; Struffert, T.; Engelhorn, T.; Richter, C. [Abt. fuer Neuroradiologie, Universitaetsklinikum Erlangen, Friedrich-Alexander-Univ. Erlangen-Nuernberg (Germany)

    2008-10-15

    Originally aimed at improving standard radiography by providing higher absorption efficiency and a wider dynamic range than available with X-ray film or film-screen combinations, flat-panel detector technology has become widely accepted for neuroangiographic imaging. In particular flat-panel detector computed tomography (FD-CT) which uses rotational C-arm-mounted flat-panel detector technology is capable of volumetric imaging with high spatial resolution. As ''Angiographic CT'' FD-CT may be helpful during many diagnostic and neurointerventional procedures, i.e. intracranial stenting for cerebrovascular stenoses, stent-assisted coil embolization of wide-necked cerebral aneurysms and embolizations of arteriovenous malformations. By providing morphologic, CT-like images of the brain within the angio suite, FD-CT is able to rapidly visualize periprocedural hemorrhage and may thus improve rapid complication management without the need for patient transfer. In addition, myelography and postmyelographic FD-CT imaging can be carried out using a single machine. Spinal interventions, such as kyphoplasty or vertebroplasty might also benefit from FD-CT. This paper briefly reviews the technical principles of FD technology and then focuses on possible applications in diagnostic and interventional neuroradiology. (orig.)

  14. Real-Time Neutron Radiography at CARR

    Institute of Scientific and Technical Information of China (English)

    HE; Lin-feng; HAN; Song-bai; WANG; Hong-li; WU; Mei-mei; WEI; Guo-hai; WANG; Yu

    2012-01-01

    <正>A real-time detector system for neutron radiography based on CMOS camera has been designed for the thermal neutron imaging facility under construction at China Advanced Research Reactor (CARR). This system is equipped with a new scientific CMOS camera with 5.5 million pixels and speed up to 100 fps at full frame. The readout noise is less than 2.4 electron per pixel. It is capable of providing

  15. Assessment of cold neutron radiography capability

    Energy Technology Data Exchange (ETDEWEB)

    McDonald, T.E. Jr.; Roberts, J.A.

    1998-12-31

    This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The authors goals were to demonstrate and assess cold neutron radiography techniques at the Los Alamos Neutron Science Center (LANSCE), Manual Lujan Neutron Scattering Center (Lujan Center), and to investigate potential applications of the capability. The authors have obtained images using film and an amorphous silicon detector. In addition, a new technique they have developed allows neutron radiographs to be made using only a narrow range of neutron energies. Employing this approach and the Bragg cut-off phenomena in certain materials, they have demonstrated material discrimination in radiography. They also demonstrated the imaging of cracks in a sample of a fire-set case that was supplied by Sandia National Laboratory, and they investigated whether the capability could be used to determine the extent of coking in jet engine nozzles. The LANSCE neutron radiography capability appears to have applications in the DOE stockpile maintenance and science-based stockpile stewardship (SBSS) programs, and in industry.

  16. Digital radiography: image quality and radiation dose.

    Science.gov (United States)

    Seibert, J Anthony

    2008-11-01

    Digital radiography devices, rapidly replacing analog screen-film detectors, are now common in diagnostic radiological imaging, where implementation has been accelerated by the commodity status of electronic imaging and display systems. The shift from narrow latitude, fixed-speed screen-film detectors to wide latitude, variable-speed digital detectors has created a flexible imaging system that can easily result in overexposures to the patient without the knowledge of the operator, thus potentially increasing the radiation burden of the patient population from radiographic examinations. In addition, image processing can be inappropriately applied causing inconsistent or artifactual appearance of anatomy, which can lead to misdiagnosis. On the other hand, many advantages can be obtained from the variable-speed digital detector, such as an ability to lower dose in many examinations, image post-processing for disease-specific conditions, display flexibility to change the appearance of the image and aid the physician in making a differential diagnosis, and easy access to digital images. An understanding of digital radiography is necessary to minimize the possibility of overexposures and inconsistent results, and to achieve the principle of as low as reasonably achievable (ALARA) for the safe and effective care of all patients. Thus many issues must be considered for optimal implementation of digital radiography, as reviewed in this article.

  17. Validation study of the thorax phantom Lungman for optimization purposes

    Science.gov (United States)

    Rodríguez Pérez, Sunay; Marshall, Nicholas W.; Struelens, Lara; Bosmans, Hilde

    2017-03-01

    This work aims to investigate the advantages and limitations of the Kyoto Kagaku thorax phantom Lungman for use in chest radiography optimization studies. First, patient survey data were gathered for chest posterior anterior (PA) and lateral (LAT) examinations in a standard chest X-ray room over a period of one year, using a Caesium Iodide (CsI) based flat panel detector with automatic exposure control (AEC). Parameters surveyed included exposure index (EI), dose area product (DAP) and AEC exposure time. PA and LAT projections of the phantom were then compared to these values. Additionally, the equivalence in millimetres of poly (methyl methacrylate) (PMMA) was established for the different regions of the Lungman phantom (lungs and mediastinum). Finally, a voxel model of the Lungman phantom was developed by the segmentation of a volumetric dataset of the phantom acquired using CT scanning. Subsequently, the model was used in Monte Carlo simulations with PENELOPE/penEasy code to calculate the energy deposited in the organs of the phantom. This enabled comparison of the phantom tissue-equivalent materials with materials defined by ICRP 89 in terms of energy deposition. For the survey data, close agreement was found between phantom and the median values for the patient data (deviations ranged from 4% to 31%, one outlier). The phantom lung region is equivalent to 89 mm to 106 mm of PMMA, depending on tube voltage. Energy deposited in the phantom material compared to those for ICRP defined material differed by at most 36% in AP irradiations and 49% in PA irradiations.

  18. SU-F-P-06: Moving From Computed Radiography to Digital Radiography: A Collaborative Approach to Improve Image Quality

    Energy Technology Data Exchange (ETDEWEB)

    Sandoval, D; Mlady, G; Selwyn, R [University of New Mexico School of Medicine, Albuquerque, NM (United States); Valenti, D; Bateman, T; Norris, V [University of New Mexico Hospital, Albuquerque, New Mexico (United States)

    2016-06-15

    Purpose: To bring together radiologists, technologists, and physicists to utilize post-processing techniques in digital radiography (DR) in order to optimize image acquisition and improve image quality. Methods: Sub-optimal images acquired on a new General Electric (GE) DR system were flagged for follow-up by radiologists and reviewed by technologists and medical physicists. Various exam types from adult musculoskeletal (n=35), adult chest (n=4), and pediatric (n=7) were chosen for review. 673 total images were reviewed. These images were processed using five customized algorithms provided by GE. An image score sheet was created allowing the radiologist to assign a numeric score to each of the processed images, this allowed for objective comparison to the original images. Each image was scored based on seven properties: 1) overall image look, 2) soft tissue contrast, 3) high contrast, 4) latitude, 5) tissue equalization, 6) edge enhancement, 7) visualization of structures. Additional space allowed for additional comments not captured in scoring categories. Radiologists scored the images from 1 – 10 with 1 being non-diagnostic quality and 10 being superior diagnostic quality. Scores for each custom algorithm for each image set were summed. The algorithm with the highest score for each image set was then set as the default processing. Results: Images placed into the PACS “QC folder” for image processing reasons decreased. Feedback from radiologists was, overall, that image quality for these studies had improved. All default processing for these image types was changed to the new algorithm. Conclusion: This work is an example of the collaboration between radiologists, technologists, and physicists at the University of New Mexico to add value to the radiology department. The significant amount of work required to prepare the processing algorithms, reprocessing and scoring of the images was eagerly taken on by all team members in order to produce better quality

  19. Role of digital tomosynthesis and dual energy subtraction digital radiography in detecting pulmonary nodules

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Sarvana G. [Department of Radiodiagnosis and Imaging, Postgraduate Institute of Medical Education and Research (PGIMER), Sector 12, Chandigarh 160012 (India); Garg, Mandeep Kumar, E-mail: gargmandeep01@gmail.com [Department of Radiodiagnosis and Imaging, Postgraduate Institute of Medical Education and Research (PGIMER), Sector 12, Chandigarh 160012 (India); Khandelwal, Niranjan; Gupta, Pankaj [Department of Radiodiagnosis and Imaging, Postgraduate Institute of Medical Education and Research (PGIMER), Sector 12, Chandigarh 160012 (India); Gupta, Dheeraj; Aggarwal, Ashutosh Nath [Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Sector 12, Chandigarh 160012 (India); Bansal, Subash Chand [Department of Radiodiagnosis and Imaging, Postgraduate Institute of Medical Education and Research (PGIMER), Sector 12, Chandigarh 160012 (India)

    2015-07-15

    Highlights: • Accuracy of digital tomosynthesis for nodule detection is substantially higher. • Improvement in diagnostic accuracy is most pronounced for nodules <10 mm. • There is five times increase in radiation dose compared to DR. - Abstract: Objective: Digital tomosynthesis (DT) and dual-energy subtraction digital radiography (DES-DR) are known to perform better than conventional radiography in the detection of pulmonary nodules. Yet the comparative diagnostic performances of DT, DES-DR and digital radiography (DR) is not known. The present study compares the diagnostic performances of DT, DES-DR and DR in detecting pulmonary nodules. Subjects and methods: The institutional Review Board approved the study and informed written consent was obtained. Fifty-five patients (30 with pulmonary nodules, 25 with non-nodular focal chest pathology) were included in the study. DT and DES-DR were performed within14 days of MDCT. Composite images acquired at high kVp as part of DES-DR were used as DR images. Images were analyzed for presence of nodules and calcification in nodules. Interpretations were assigned confidence levels from 1 to 5 according to Five-Point rating scale. Areas under the receiver operating characteristic curves were compared using Z test. Results: A total of 110 (88 non-calcified, 22 calcified) nodules were identified on MDCT. For detection of nodules, DR showed cumulative sensitivity and specificity of 25.45% and 67.97%, respectively. DT showed a cumulative sensitivity and specificity of 60.9% and 85.07%, respectively. The performance was significantly better than DR (p < 0.003). DES-DR showed sensitivity and specificity of 27.75% and 82.64%, not statistically different from those of DR (p—0.92). In detection of calcification, there was no statistically significant difference between DT, DES-DR and DR. Conclusions: DT performs significantly better than DES-DR and DR at the cost of moderate increase in radiation dose.

  20. Remote interpretation of chest roentgenograms.

    Science.gov (United States)

    Andrus, W S; Hunter, C H; Bird, K T

    1975-04-01

    A series of 98 chest films was interpreted by two physicians on the basis of monitor display of the transmitted television signal representing the roentgenographic image. The transmission path was 14 miles long, and included one active repeater station. Receiver operating characteristic curves were drawn to compare interpretations rendered on television view of the image with classic, direct view interpretations of the same films. Performance in these two viewing modes was found to be quite similar. When films containing only hazy densities lacking internal structure or sharp margins, were removed from the sample, interpretation of the remaining films was essentially identical via the two modes. Since hazy densities are visible on retrospective examination, interpretation of roentgenograms at a distance via television appears to be a feasible route for delivery of radiologic services.

  1. Systematic Interpretation of Adult Thorax Radiography

    Directory of Open Access Journals (Sweden)

    Torel Ogur

    2009-10-01

    Full Text Available Thorax x-ray film is a routine radiological test which is commonly ordered, relatively inexpensive and available for most of the health services. It also offers numerous useful information in medical decision making in a lot of clinical situations. So it is very important to learn to interpret effectively chest x ray film in clinical practice, for medical students and physicians. This review is intended to give a basic opinion for systematic review of chest x-ray film. [TAF Prev Med Bull 2009; 8(5.000: 427-436

  2. Chest pain and exacerbations of bronchiectasis

    Directory of Open Access Journals (Sweden)

    King PT

    2012-12-01

    Full Text Available Paul T King,1,2 Stephen R Holdsworth,2 Michael Farmer,1 Nicholas J Freezer,1 Peter W Holmes11Department of Respiratory and Sleep Medicine, 2Monash University Department of Medicine, Monash Medical Centre, Melbourne, Victoria, AustraliaBackground: Bronchiectasis is a common disease and a major cause of respiratory morbidity. Chest pain has been described as occurring in the context of bronchiectasis but has not been well characterized. This study was performed to describe the characteristics of chest pain in adult bronchiectasis and to define the relationship of this pain to exacerbations.Subjects and methods: We performed a prospective study of 178 patients who were followed-up for 8 years. Subjects were reviewed on a yearly basis and assessed for the presence of chest pain. Subjects who had chest pain at the time of clinical review by the investigators were included in this study. Forty-four patients (25% described respiratory chest pain at the time of assessment; in the majority of cases 39/44 (89%, this occurred with an exacerbation and two distinct types of chest pain could be described: pleuritic (n = 4 and non-pleuritic (n = 37, with two subjects describing both forms. The non-pleuritic chest pain occurred most commonly over both lower lobes and was mild to moderate in severity. The pain subsided as patients recovered. Conclusion: Non-pleuritic chest pain occurs in subjects with bronchiectasis generally in association with exacerbations.Keywords: sputum, collapse, bronchitis, airway obstruction

  3. Comparison of radiography and ultrasonography in the detection of lung and liver cysts in cattle and buffaloes

    Directory of Open Access Journals (Sweden)

    Ashwani Kumar

    2016-10-01

    Full Text Available Aim: Echinococcosis is the major cause of lung and liver cysts in ruminants. This study compared usefulness of radiography and ultrasonography (USG in the detection of lung and/or liver cysts in sick bovine animals. The study also worked out cooccurrence of lung and liver cysts, and whether these cysts were primary cause of sickness or not. Materials and Methods: This study was conducted on 45 sick bovine (37 buffaloes and 8 cattle suffering from lung and liver cysts. A complete history of illness and clinical examination was carried out. Lateral radiographs of chest and reticular region were taken. In radiographically positive or suspected cases of cysts, USG of the lung and liver region was done. Depending on the location of cyst and clinical manifestations of the animal, the cysts were categorized as primary or secondary causes of sickness. Results: Using either imaging technique, it was observed that 46.7% of the animals had both lung and liver cysts, whereas 33.3% had only lung and 20% had only liver cyst. Cysts were identified as primary cause of sickness in 31.1% animals only. For diagnosing lung cysts, radiography (71.1% and USG (62.2% had similar diagnostic utility. However, for detecting liver cysts, USG was the only imaging tool. Conclusion: The lung and liver cysts, depending on their number and size may be a primary cause of sickness in bovine. Radiography and USG are recommended, in combination, as screening tools to rule out echinococcosis.

  4. Spiral CT for evaluation of chest trauma; Spiral-CT beim Thoraxtrauma

    Energy Technology Data Exchange (ETDEWEB)

    Roehnert, W. [Universitaetsklinikum Dresden (Germany). Inst. und Poliklinik fuer Radiologische Diagnostik; Weise, R. [Universitaetsklinikum Dresden (Germany). Inst. und Poliklinik fuer Radiologische Diagnostik

    1997-07-01

    After implementation of spiral CT in our department, we carried out an analysis for determining anew the value of CT as a modality of chest trauma diagnosis in the emergency department. The retrospective study covers a period of 10 months and all emergency patients with chest trauma exmined by spiral CT. The major lesions of varying seriousness covered by this study are: pneumothorax, hematothorax, pulmonary contusion or laceration, mediastinal hematoma, rupture of a vessel, injury of the heart and pericardium. The various fractures are not included in this study. In many cases, spiral CT within relatively short time yields significant diagnostic findings, frequently saving additional angiography. A rigid diagnostic procedure cannot be formulated. Plain-film chest radiography still remains a diagnostic modality of high value. (Orig.) [Deutsch] Nach Einfuehrung der Spiral-CT in unserer Einrichtung versuchten wir, den Stellenwert der Computertomographie in der Notfalldiagnostik des Thoraxtraumas neu zu bestimmen. Dazu wurden retrospektiv ueber einen Zeitraum von 10 Monaten alle mittels Spiral-CT untersuchten Notfallpatienten mit Thoraxverletzungen ausgewertet. Im Vordergrund standen folgende Befunde unterschiedlichen Schweregrades: Pneumothorax, Haematothorax, Lungenkontusion/-lazeration, Mediastinalhaematom, Gefaessruptur, Herz- und Herzbeutelverletzung. Auf die unterschiedlichen Frakturen wird bewusst nicht naeher eingegangen. In vielen Faellen liefert die Spiral-CT mit relativ geringem Zeitaufwand wesentliche diagnostische Aussagen. Haeufig kann auf eine Angiographie verzichtet werden. Ein starres diagnostisches Stufenschema laesst sich nicht definieren. Die Thoraxuebersichtsaufnahme besitzt einen unveraendert hohen Stellenwert. (orig.)

  5. Evaluation of effective dose with chest digital tomosynthesis system using Monte Carlo simulation

    Science.gov (United States)

    Kim, Dohyeon; Jo, Byungdu; Lee, Youngjin; Park, Su-Jin; Lee, Dong-Hoon; Kim, Hee-Joung

    2015-03-01

    Chest digital tomosynthesis (CDT) system has recently been introduced and studied. This system offers the potential to be a substantial improvement over conventional chest radiography for the lung nodule detection and reduces the radiation dose with limited angles. PC-based Monte Carlo program (PCXMC) simulation toolkit (STUK, Helsinki, Finland) is widely used to evaluate radiation dose in CDT system. However, this toolkit has two significant limits. Although PCXMC is not possible to describe a model for every individual patient and does not describe the accurate X-ray beam spectrum, Geant4 Application for Tomographic Emission (GATE) simulation describes the various size of phantom for individual patient and proper X-ray spectrum. However, few studies have been conducted to evaluate effective dose in CDT system with the Monte Carlo simulation toolkit using GATE. The purpose of this study was to evaluate effective dose in virtual infant chest phantom of posterior-anterior (PA) view in CDT system using GATE simulation. We obtained the effective dose at different tube angles by applying dose actor function in GATE simulation which was commonly used to obtain the medical radiation dosimetry. The results indicated that GATE simulation was useful to estimate distribution of absorbed dose. Consequently, we obtained the acceptable distribution of effective dose at each projection. These results indicated that GATE simulation can be alternative method of calculating effective dose in CDT applications.

  6. Role of chest computed tomography in prevention of occupational respiratory disease: review of recent literature.

    Science.gov (United States)

    Weissman, David N

    2015-06-01

    This review provides an update on literature published over the past 5 years that is relevant to using chest computed tomography (CT) as a tool for preventing occupational respiratory disease. An important area of investigation has been in the use of low-dose CT (LDCT) to screen asbestos-exposed populations for lung cancer. Two recent systematic reviews have reached conclusions in support of screening. Based on the limited evidence that is currently available, the Finnish Institute of Occupational Health has recommended LDCT screening in asbestos-exposed individuals if their personal combination of risk factors yields a risk for lung cancer equal to that needed for entry into the National Lung Screening Trial. It has also recommended further research, such as to document the optimal frequency of screening and the effectiveness of screening. Recent literature continues to support high-resolution CT (HRCT) as being more sensitive than chest radiography in detecting pneumoconiosis. However, there are insufficient data to determine the effectiveness of HRCT screening in improving individual outcomes if used in screening for pneumoconiosis and its routine use for this purpose cannot be recommended. However, if HRCT is used to evaluate populations, recent literature shows that the International Classification of HRCT for Occupational and Environmental Respiratory Diseases provides an important tool for reproducible evaluation and recording of findings. HRCT is an important tool for individual patient management and recent literature has documented that chest HRCT findings are significantly associated with outcomes such as pulmonary function and mortality.

  7. FINDINGS OF CHEST RADIOGRAPH AND SPIRAL COMPUTED TOMOGRAPHY IN SWYER-JAMES SYNDROME

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Objective To evaluate the value of X-ray and spiral computed tomography (SCT) in the diagnosis of SwyerJames syndrome (SJS).Methods A total of 28 patients, 12 males and 16 females, were studied retrospectively. Ages ranged from 11 to 57 years, the mean age was 32 years. All patients underwent inspiratory chest X-ray films, 5 with expiratory chest films and 1 with bronchogram. Furthermore, inspiratory and expiratory SCT scans were performed. The SCT findings were analyzed and compared with X-ray films.Results SCT demonstrated 56 lobes with hyperlucency and diminished vascularity. The size of 51 lobes were smaller and 5 were normal. X-ray films showed that hyperlucency was only in 29 lobes, in which 19 lobes were smallsized and the other 10 lobes normal. There were 56 lobes with air-trapping on expiratory SCT scans, but only 5 lobes with air-trapping on expiratory X-ray films. Bronchogram in 1 case demonstrated bronchiectasis and bronchiolitis obliterans. SCT showed 24 patients with bronchiectasis, 9 patients with tuberculosis, 10 patients with bronchiolitis, and 2 with segmental collapse. Conclusion SCT scan is superior to chest radiography in the diagnosis and differential diagnosis of SJS.

  8. Lung involvement quantification in chest radiographs; Quantificacao de comprometimento pulmonar em radiografias de torax

    Energy Technology Data Exchange (ETDEWEB)

    Giacomini, Guilherme; Alvarez, Matheus; Oliveira, Marcela de; Miranda, Jose Ricardo A. [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Botucatu, SP (Brazil). Instituto de Biociencias. Departamento de Fisica e Biofisica; Pina, Diana R.; Pereira, Paulo C.M.; Ribeiro, Sergio M., E-mail: giacomini@ibb.unesp.br [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Botucatu, SP (Brazil). Faculdade de Medicina. Departamento de Doencas Tropicais e Diagnostico por Imagem

    2014-12-15

    Tuberculosis (TB) caused by Mycobacterium tuberculosis, is an infectious disease which remains a global health problem. The chest radiography is the commonly method employed to assess the TB's evolution. The methods for quantification of abnormalities of chest are usually performed on CT scans (CT). This quantification is important to assess the TB evolution and treatment and comparing different treatments. However, precise quantification is not feasible for the amount of CT scans required. The purpose of this work is to develop a methodology for quantification of lung damage caused by TB through chest radiographs. It was developed an algorithm for computational processing of exams in Matlab, which creates a lungs' 3D representation, with compromised dilated regions inside. The quantification of lung lesions was also made for the same patients through CT scans. The measurements from the two methods were compared and resulting in strong correlation. Applying statistical Bland and Altman, all samples were within the limits of agreement, with a confidence interval of 95%. The results showed an average variation of around 13% between the two quantification methods. The results suggest the effectiveness and applicability of the method developed, providing better risk-benefit to the patient and cost-benefit ratio for the institution. (author)

  9. How do radiologists do it? The influence of experience and training on searching for chest nodules

    Energy Technology Data Exchange (ETDEWEB)

    Manning, David [Department of Medical Imaging Sciences, St Martin' s College, Lancaster LA1 3JD (United Kingdom)]. E-mail: d.manning@ucsm.ac.uk; Ethell, Susan [Department of Medical Imaging Sciences, St Martin' s College, Lancaster LA1 3JD (United Kingdom); Donovan, Tim [Department of Medical Imaging Sciences, St Martin' s College, Lancaster LA1 3JD (United Kingdom); Crawford, Trevor [Department of Psychology, Lancaster University, Lancaster (United Kingdom)

    2006-05-15

    Four observer groups with different levels of expertise were tested to investigate the nature of expert performance. The task was the detection and localisation of significant pulmonary nodules in postero-anterior views of the chest. One hundred and twenty digitised chest images were used. The observer groups were 8 experienced radiologists, 5 experienced radiographers before and after six months training in chest image interpretation, and 8 undergraduate radiography students. Eye tracking was carried out to investigate differences in visual search strategies between observers. Detection performance was measured with an Alternate Free Response Operating Characteristic technique. Performance measures showed the experienced group of radiologists plus radiographers after training were better at the task than the remainder (t-test p = 0.046). Differences were shown in the eye-tracking parameters between the groups: saccadic amplitude (ANOVA p 0.00047), number of fixations before and after training (t-test p = 0.041), and scrutiny time per decision and per film for the experienced versus the inexperienced observers (t-test p = 0.02). Visual coverage reduced with increasing level of experience but this result did not reach significance. Generally there were distinct differences in the search strategies between the experienced and inexperienced observers and we discuss the significance of these findings. We believe the results support some recent theoretical models of expert performance and that the findings may prove to be helpful in 'fast-track' educational programmes of image interpretation for non-radiology practitioners.

  10. Solitary Plasmacytoma of the Chest Wall

    Directory of Open Access Journals (Sweden)

    Servet Kayhan

    2014-03-01

    Full Text Available A previously healthy 55-year-old man with right sided lateral chest pain admitted to clinic. It was found a solid and painful mass at the right 4th rib in physical examination. Chest X-ray and thoracic computarized tomography showed an opacity measured 60x33 mm within the right chest wall destructing the 4th rib. Needle aspiration was performed from tumor and cytologic examination showed atypic plasma cell infiltration. The patient was scheduled for a chest wall resection and reconstructive surgery. Examination of a permanent section showed that the chest wall tumor was solitary plasmacytoma. There was no evidence of multiple myeloma recurrence after two years from the operation.

  11. Venous chest anatomy: clinical implications

    Energy Technology Data Exchange (ETDEWEB)

    Chasen, M.H.; Charnsangavej, C. [Department of Diagnostic Imaging, The University of Texas, M.D. Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, Texas 77030 (United States)

    1998-03-01

    This article provides a practical approach to the clinical implications and importance of understanding the collateral venous anatomy of the thorax. Routine radiography, conventional venography, computed tomography (CT), and magnetic resonance (MR) imaging studies provide correlative anatomic models for the demonstration of how interconnecting collateral vascular networks within the thorax maintain venous stability at all times. Five major systems comprise the collateral venous network of the thorax ( Fig. 1 ). These include the paravertebral, azygos-hemiazygos, internal mammary, lateral thoracic, and anterior jugular venous systems (AJVS). The five systems are presented in the following sequence: (a) a brief introduction to the importance of catheter position and malposition in understanding access to the thoracic venous system, (b) the anatomy of the azygos-hemiazygos systems and their relationship with the paravertebral plexus, (c) the importance of the AJVS, (d) 'loop' concepts interconnecting the internal mammary and azygos-hemiazygos systems by means of the lateral thoracic and intercostal veins, and (e) the interconnecting venous networks on the thoracic side of the thoracoabdominal junction. Certain aspects of the venous anatomy of the thorax will not be discussed in this chapter and include (a) the intra-abdominal anastomoses between the superior and inferior vena cavae (IVC) via the internal mammary, lateral thoracic, and azygos-hemiazygos systems (beyond the scope of this article), (b) potential collateral vessels involving vertebral, parascapular, thyroidal, thymic, and other smaller veins that might anastomose with the major systems, and (c) anatomic variants and pitfalls that may mimic pathologic conditions (space limitations). (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  12. Computed radiography in an emergency department setting

    Science.gov (United States)

    Andriole, Katherine P.; Gould, Robert G.; Arenson, Ronald L.

    1997-05-01

    Evaluation of radiologist and non-radiologist physician acceptance of computed radiography (CR) as an alternative to film-based radiography in an emergency department (ED) is performed. All emergency department radiographs are performed using photostimulable phosphor plates and rad by a computed radiography laser reader placed in the former emergency department darkroom. Soft copy images are simultaneously transmitted to high- and medium-resolution dual-monitor display stations located in radiology and ED reading rooms respectively. The on-call radiologist is automatically paged by the Radiology Information System (RIS) upon exam completion, to read the new ED imaging study. Patient demographic information including relevant clinical history is conveyed to the radiologist via the RIS. A 'wet read' preliminary radiology report is immediately transmitted back to the ED. Radiology and ED physicians are surveyed to ascertain preferences for CR or traditional screen-film, based on system implementation, image viewing and clinical impact issues. Preliminary results indicate a preference for filmless CR among the ED physicians if digital reliability and speed issues are met. This preference appears to be independent of physician level of experience. Inexperienced radiologists-in-training appear to have less comfort with softcopy reading for primary diagnosis. However, additional training in softcopy reading techniques can improve confidences. Image quality issues are most important tot he radiologist, while speed and reliability are the major issues for ED physicians. Reasons for CR preference include immediate access to images on display stations, near-zero exam retake rates, and improved response time and communication between radiology and the emergency department clinician.

  13. [Chest pains in the dental environment].

    Science.gov (United States)

    Garfunkel, A; Galili, D; Findler, M; Zusman, S P; Malamed, S F; Elad, S; Kaufman, E

    2002-01-01

    Chest pain does not necessarily indicate cardiac disease. The most common causes of acute chest pain encountered in dental situations include hyperventilation, pulmonary embolism, angina pectoris and myocardial infarction. Stress and fear often cause rapid breathing or hyperventilation. This usually occurs in young adults and although the hyperventilating patient often complains of chest pain, this is rarely a manifestation of cardiac disease. Pulmonary embolism usually indicates the occlusion of a pulmonary artery causing severe chest pain. The primary clinical manifestation of angina pectoris is chest pain. Although most instances of anginal pain are easily terminated, the dentist must always consider the possibility that the supposed anginal attack is actually a sign of acute myocardial infarction (AMI). AMI is a clinical syndrome caused by a deficient coronary arterial blood supply to a region of myocardium that results in cellular death. There is a high incidence of mortality among AMI with death often occurring within 2 hours of the onset of signs and symptoms. The initial clinical manifestations of all types of chest pain can be similar. Therefore the dentist must develop proficiency in constituting a differential diagnosis and an efficient management protocol. As in most medical situations prevention is the most powerful tool. However, if chest pains do occur, measures such as airway management, oxygen supplementation, coronary artery dilation, analgesis and in extreme cases, cardiopulmonary resuscitation and evacuation to the emergency room, may be necessary.

  14. Whole-Body Clinical Applications of Digital Tomosynthesis.

    Science.gov (United States)

    Machida, Haruhiko; Yuhara, Toshiyuki; Tamura, Mieko; Ishikawa, Takuya; Tate, Etsuko; Ueno, Eiko; Nye, Katelyn; Sabol, John M

    2016-01-01

    With flat-panel detector mammography, radiography, and fluoroscopy systems, digital tomosynthesis (DT) has been recently introduced as an advanced clinical application that removes overlying structures, enhances local tissue separation, and provides depth information about structures of interest by providing high-quality tomographic images. DT images are generated from projection image data, typically using filtered back-projection or iterative reconstruction. These low-dose x-ray projection images are easily and swiftly acquired over a range of angles during a single linear or arc sweep of the x-ray tube assembly. DT is advantageous in a variety of clinical contexts, including breast, chest, head and neck, orthopedic, emergency, and abdominal imaging. Specifically, compared with conventional mammography, radiography, and fluoroscopy, as a result of reduced tissue overlap DT can improve detection of breast cancer, pulmonary nodules, sinonasal mucosal thickening, and bone fractures and delineation of complex anatomic structures such as the ostiomeatal unit, atlantoaxial joint, carpal and tarsal bones, and pancreatobiliary and gastrointestinal tracts. Compared with computed tomography, DT offers reduced radiation exposure, better in-plane resolution to improve assessment of fine bony changes, and less metallic artifact, improving postoperative evaluation of patients with metallic prostheses and osteosynthesis materials. With more flexible patient positioning, DT is also useful for functional, weight-bearing, and stress tests. To optimize patient management, a comprehensive understanding of the clinical applications and limitations of whole-body DT applications is important for improvement of diagnostic quality, workflow, and cost-effectiveness. Online supplemental material is available for this article. (©)RSNA, 2016.

  15. Axial Tomography from Digitized Real Time Radiography

    Science.gov (United States)

    Zolnay, A. S.; McDonald, W. M.; Doupont, P. A.; McKinney, R. L.; Lee, M. M.

    1985-01-18

    Axial tomography from digitized real time radiographs provides a useful tool for industrial radiography and tomography. The components of this system are: x-ray source, image intensifier, video camera, video line extractor and digitizer, data storage and reconstruction computers. With this system it is possible to view a two dimensional x-ray image in real time at each angle of rotation and select the tomography plane of interest by choosing which video line to digitize. The digitization of a video line requires less than a second making data acquisition relatively short. Further improvements on this system are planned and initial results are reported.

  16. Digital Radiography Qualification of Tube Welding

    Science.gov (United States)

    Carl, Chad

    2012-01-01

    The Orion Project will be directing Lockheed Martin to perform orbital arc welding on commodities metallic tubing as part of the Multi Purpose Crew Vehicle assembly and integration process in the Operations and Checkout High bay at Kennedy Space Center. The current method of nondestructive evaluation is utilizing traditional film based x-rays. Due to the high number of welds that are necessary to join the commodities tubing (approx 470), a more efficient and expeditious method of nondestructive evaluation is desired. Digital radiography will be qualified as part of a broader NNWG project scope.

  17. Digital radiography in the aerospace industry

    Science.gov (United States)

    Buchanan, R. A.; Bueno, C.; Barry, R. C.; Barker, M. D.

    An account is given of the bases of digital radiography (DR), with a view to the identification of NDE systems with the greatest usefulness to the aerospace industry and the nature of the advanced image processing and reconstruction techniques that have been devised thus far. The spatial resolution of any DR system is fundamentally limited by the number of pixels in the digital image and the system field-of-view. Attention is given to the problems of image geometric unsharpness and radiation quantum noise limits, as well as to the potential role of advanced DR in future NDT of aerospace components.

  18. Chest CT in children: anesthesia and atelectasis

    Energy Technology Data Exchange (ETDEWEB)

    Newman, Beverley; Gawande, Rakhee [Lucile Packard Children' s Hospital, Department of Radiology, Stanford, CA (United States); Krane, Elliot J. [Stanford University School of Medicine, Lucile Packard Children' s Hospital, Department of Anesthesiology, Perioperative and Pain Medicine, Stanford, CA (United States); Holmes, Tyson H. [Stanford University School of Medicine, Lucile Packard Children' s Hospital, Department of Psychiatry and Behavioral Sciences, Stanford, CA (United States); Robinson, Terry E. [Stanford University School of Medicine, Lucile Packard Children' s Hospital, Department of Pulmonary Medicine and Cystic Fibrosis Center for Excellence in Pulmonary Biology, Stanford, CA (United States)

    2014-02-15

    There has been an increasing tendency for anesthesiologists to be responsible for providing sedation or anesthesia during chest CT imaging in young children. Anesthesia-related atelectasis noted on chest CT imaging has proven to be a common and troublesome problem, affecting image quality and diagnostic sensitivity. To evaluate the safety and effectiveness of a standardized anesthesia, lung recruitment, controlled-ventilation technique developed at our institution to prevent atelectasis for chest CT imaging in young children. Fifty-six chest CT scans were obtained in 42 children using a research-based intubation, lung recruitment and controlled-ventilation CT scanning protocol. These studies were compared with 70 non-protocolized chest CT scans under anesthesia taken from 18 of the same children, who were tested at different times, without the specific lung recruitment and controlled-ventilation technique. Two radiology readers scored all inspiratory chest CT scans for overall CT quality and atelectasis. Detailed cardiorespiratory parameters were evaluated at baseline, and during recruitment and inspiratory imaging on 21 controlled-ventilation cases and 8 control cases. Significant differences were noted between groups for both quality and atelectasis scores with optimal scoring demonstrated in the controlled-ventilation cases where 70% were rated very good to excellent quality scans compared with only 24% of non-protocol cases. There was no or minimal atelectasis in 48% of the controlled ventilation cases compared to 51% of non-protocol cases with segmental, multisegmental or lobar atelectasis present. No significant difference in cardiorespiratory parameters was found between controlled ventilation and other chest CT cases and no procedure-related adverse events occurred. Controlled-ventilation infant CT scanning under general anesthesia, utilizing intubation and recruitment maneuvers followed by chest CT scans, appears to be a safe and effective method to obtain

  19. Chest pain: a time for concern?

    Science.gov (United States)

    King, Joan E; Magdic, Kathy S

    2014-01-01

    When a patient complains of chest pain, the first priority is to establish whether the situation is life threatening. Life-threatening differential diagnoses that clinicians must consider include acute coronary syndrome, cardiac tamponade, pulmonary embolus, aortic dissection, and tension pneumothorax. Nonthreatening causes of chest pain that should be considered include spontaneous pneumothorax, pleural effusion, pneumonia, valvular diseases, gastric reflux, and costochondritis. The challenge for clinicians is not to be limited by "satisfaction of search" and fail to consider important differential diagnoses. The challenge, however, can be met by developing a systematic method to assess chest pain that will lead to the appropriate diagnosis and appropriate treatment plan.

  20. Chest pain of cardiac and noncardiac origin.

    Science.gov (United States)

    Lenfant, Claude

    2010-10-01

    Chest pain is one of the most common symptoms driving patients to a physician's office or the hospital's emergency department. In approximately half of the cases, chest pain is of cardiac origin, either ischemic cardiac or nonischemic cardiac disease. The other half is due to noncardiac causes, primarily esophageal disorder. Pain from either origin may occur in the same patient. In addition, psychological and psychiatric factors play a significant role in the perception and severity of the chest pain, irrespective of its cause. Chest pain of ischemic cardiac disease is called angina pectoris. Stable angina may be the prelude of ischemic cardiac disease; and for this reason, it is essential to ensure a correct diagnosis. In most cases, further testing, such as exercise testing and angiography, should be considered. The more severe form of chest pain, unstable angina, also requires a firm diagnosis because it indicates severe coronary disease and is the earliest manifestation of acute myocardial infarction. Once a diagnosis of stable or unstable angina is established, and if a decision is made not to use invasive therapy, such as coronary bypass, percutaneous transluminal coronary angioplasty, or stent insertion, effective medical treatment of associated cardiac risk factors is a must. Acute myocardial infarction occurring after a diagnosis of angina greatly increases the risk of subsequent death. Chest pain in women warrants added attention because women underestimate their likelihood to have coronary heart disease. A factor that complicates the clinical assessment of patients with chest pain (both cardiac and noncardiac in origin) is the relatively common presence of psychological and psychiatric conditions such as depression or panic disorder. These factors have been found to cause or worsen chest pain; but unfortunately, they may not be easily detected. Noncardiac chest pain represents the remaining half of all cases of chest pain. Although there are a number of

  1. Preliminary Study of Indirect Neutron Radiography Method at CARR

    Institute of Scientific and Technical Information of China (English)

    WEI; Guo-hai; HAN; Song-bai; WANG; Hong-li; HE; Lin-feng; WANG; Yu; WU; Mei-mei; LIU; Yun-tao; CHEN; Dong-feng

    2013-01-01

    The Indirect Neutron Radiography is a powerful technique for non-destructively measuring specimens with radioactivity in the nuclear industrial field.China Advanced Research Reactor(CARR)is an excellent platform for Indirect Neutron Radiography and the experimental conditions based on CARR,mainly the first and the second exposure time,have been calculated and analyzed by the Monte Carlo

  2. Local-Reference Patient Dose Evaluation in Conventional Radiography Examinations in Mazandaran, Iran

    Directory of Open Access Journals (Sweden)

    Khoshdel-Navi D.

    2016-06-01

    Full Text Available Background: The most efficient application of ionizing radiation is serving medical purposes and using this radiation has caused people to learn that artificial sources of radiation exposure among these resources can be of highest exposure rate. Obiective: The present study is aimed at initially establishing a baseline for localreference dose level in Mazandaran, Iran in 12 projections of the most conventional x-ray examination. Methods: In this study, 13 public hospitals in Mazandaran province were selected for review and required data collected for ten adult patients with mean weight of 70±10kg in each projection. Then, information of each center was separately analyzed. Next, in order to measure x-ray output tube, the dosimeter RTI model Barracuda calibrated has been applied for measuring air karma within energy rage of 40-150kvp. ESAK and ESD parameters, usually used for monitoring DRL in conventional radiography, were calculated. Results: Mean ESDs in this study has been obtained to 1.47±0.98 for skull (PA/ AP, 1.01±0.79 for skull (LAT, 0.67±0.38 for cervical spine (AP, 0.79±0.37 for cervical (LAT, 0.49±0.38 for chest (PA/AP, 1.06±0.44 for chest (LAT, 2.15±0.73 for thoracic spine (AP, 3±0.87 for thoracic spine (LAT, 2.81 ±0.82 for lumbar spine (AP, 4.28±0.78 for lumbar (LAT, 2.07±1.17 for abdomen and 1.90±0.99 for pelvis, respectively. The ESDs calculated for chest examination in both projections, PA and LAT are more than values recommended by the UK (2000, Brazil and Slovenia. Conclusion: The present study has determined wide variations in radiation dose of x-ray examinations among hospitals in Mazandaran, Iran. In order to reduce skin dose, an optimization procedure should be considered. Application of a reference dose (DRL could be a practical method for this purpose. The role of optimization of radiography parameters for reducing patient dose is a significant issue. Through optimizing parameters, it would be possible to

  3. Simulation of computed radiography with imaging plate detectors

    Energy Technology Data Exchange (ETDEWEB)

    Tisseur, D.; Costin, M. [CEA LIST, CEA Saclay 91191 Gif sur Yvette Cedex (France); Mathy, F. [CEA-LETI, Campus Minatec, F-38054, Grenoble (France); Schumm, A. [EDF R and D, 1 avenue du général de gaulle 92141 Clamart (France)

    2014-02-18

    Computed radiography (CR) using phosphor imaging plate detectors is taking an increasing place in Radiography Testing. CR uses similar equipment as conventional radiography except that the classical X-ray film is replaced by a numerical detector, called image plate (IP), which is made of a photostimulable layer and which is read by a scanning device through photostimulated luminescence. Such digital radiography has already demonstrated important benefits in terms of exposure time, decrease of source energies and thus reduction of radioprotection area besides being a solution without effluents. This paper presents a model for the simulation of radiography with image plate detectors in CIVA together with examples of validation of the model. The study consists in a cross comparison between experimental and simulation results obtained on a step wedge with a classical X-ray tube. Results are proposed in particular with wire Image quality Indicator (IQI) and duplex IQI.

  4. Digital radiography image quality: image processing and display.

    Science.gov (United States)

    Krupinski, Elizabeth A; Williams, Mark B; Andriole, Katherine; Strauss, Keith J; Applegate, Kimberly; Wyatt, Margaret; Bjork, Sandra; Seibert, J Anthony

    2007-06-01

    This article on digital radiography image processing and display is the second of two articles written as part of an intersociety effort to establish image quality standards for digital and computed radiography. The topic of the other paper is digital radiography image acquisition. The articles were developed collaboratively by the ACR, the American Association of Physicists in Medicine, and the Society for Imaging Informatics in Medicine. Increasingly, medical imaging and patient information are being managed using digital data during acquisition, transmission, storage, display, interpretation, and consultation. The management of data during each of these operations may have an impact on the quality of patient care. These articles describe what is known to improve image quality for digital and computed radiography and to make recommendations on optimal acquisition, processing, and display. The practice of digital radiography is a rapidly evolving technology that will require timely revision of any guidelines and standards.

  5. H1N1 influenza in an Irish population: patterns of chest radiograph abnormality in patients testing positive.

    LENUS (Irish Health Repository)

    O'Sullivan, K

    2012-02-29

    The winter of 2010\\/2011 saw a second peak in the number of H1N1 cases detected in Ireland. The purpose of this study was to investigate the radiological characteristics of patients diagnosed during this period. A retrospective analysis of these cases was performed. Chest radiographs were classified as normal or abnormal. A total of 37 patients were included. Of these, 22 (59%) of chest radiographs were abnormal and 15 (41%) were normal. In the 7 paediatric patients, 4 (57%) had a perihilar distribution of disease, 2 (28%) had peripherally based disease with 1 (14%) having a mixed distribution. A series of radiographs was available for 9 patients, 6 of these showed a radiographic deterioration from the initial study. The majority of chest radiographs of patients with confirmed H1N1 infection will be abnormal. In children, disease is more likely to be perihilar in distribution. Chest radiography is an important initial investigation in patients with H1N1 infection and is useful to track progression of disease in the subset of patients requiring hospitalization for severe disease.

  6. Nuclear track radiography of 'hot' aerosol particles

    CERN Document Server

    Boulyga, S F; Kievets, M K; Lomonosova, E M; Zhuk, I V; Yaroshevich, O I; Perelygin, V P; Petrova, R I; Brandt, R; Vater, P

    1999-01-01

    Nuclear track radiography was applied to identify aerosol 'hot' particles which contain elements of nuclear fuel and fallout after Chernobyl NPP accident. For the determination of the content of transuranium elements in radioactive aerosols the measurement of the alpha-activity of 'hot' particles by SSNTD was used in this work, as well as radiography of fission fragments formed as a result of the reactions (n,f) and (gamma,f) in the irradiation of aerosol filters by thermal neutrons and high energy gamma quanta. The technique allowed the sizes and alpha-activity of 'hot' particles to be determined without extracting them from the filter, as well as the determination of the uranium content and its enrichment by sup 2 sup 3 sup 5 U, sup 2 sup 3 sup 9 Pu and sup 2 sup 4 sup 1 Pu isotopes. Sensitivity of determination of alpha activity by fission method is 5x10 sup - sup 6 Bq per particle. The software for the system of image analysis was created. It ensured the identification of track clusters on an optical imag...

  7. Clinical Applications of Reverse Panoramic Radiography

    Directory of Open Access Journals (Sweden)

    Sujatha S Reddy

    2011-09-01

    Full Text Available The essence of oral and maxil-lofacial radiology is not only to be an important tool in the diagnostic assessment of dental patients but also to equip the clinician with the ability to interpret images of certain maxillocraniofacial structures of importance to dental, medical and surgical practices. Although combinations of several conven-tional x-ray projections can be adequate in a number of clinical situations, radiographic assessment of certain craniofacial structures some-times needs to be facilitated by other imaging modalities. A not-so-recent development called reverse panoramic radiography may be a useful adjuvant to such a situation, at least in the near future. It is essentially a technique where the patient is placed backwards in the panoramic machine in a reverse position in such a way that x-ray beam is directed through the patient’s face and the exit beam then passes through the patient’s head on the opposite side where it is captured on the receptor. The following manuscript is an attempt to throw light on this technique and the impact it may have on dental, medical and surgical practices. The advantages and disadvantages of reverse panoramic radiography and it’s comparison to conventional panoramic radiographs and other skull views are also dis-cussed.

  8. Common Acupoints in Chest and Abdomen

    Institute of Scientific and Technical Information of China (English)

    Journal of Acupuncture and Tuina Science Editor; CUI Xue-jun

    2003-01-01

    @@ Tiantu (CV 21) Location: In the center of the suprasternal fossa(Fig. l ). Indications: Cough, dyspnea, chest pain, pharyngolaryngeal swelling and pains, sudden hoarseness of the voice, goiter, globus hystericus, and dysphagia.

  9. THE DEADLY DOZEN OF CHEST TRAUMA

    African Journals Online (AJOL)

    Enrique

    Severe chest injuries are responsible for 25% of all trauma deaths, and in a ... mechanical compression of the trachea, laryngeal trauma such as thyroid or cricoid ... Unit Head at Chris Hani .... mechanical ventilation to 'internally splint' the ...

  10. Tuberculosis, advanced - chest x-rays (image)

    Science.gov (United States)

    Tuberculosis is an infectious disease that causes inflammation, the formation of tubercules and other growths within tissue, ... death. These chest x-rays show advanced pulmonary tuberculosis. There are multiple light areas (opacities) of varying ...

  11. High Brightness Neutron Source for Radiography

    Energy Technology Data Exchange (ETDEWEB)

    Cremer, J. T.; Piestrup, Melvin, A.; Gary, Charles, K.; Harris, Jack, L. Williams, David, J.; Jones, Glenn, E.; Vainionpaa, J. , H.; Fuller, Michael, J.; Rothbart, George, H.; Kwan, J., W.; Ludewigt, B., A.; Gough, R.., A..; Reijonen, Jani; Leung, Ka-Ngo

    2008-12-08

    This research and development program was designed to improve nondestructive evaluation of large mechanical objects by providing both fast and thermal neutron sources for radiography. Neutron radiography permits inspection inside objects that x-rays cannot penetrate and permits imaging of corrosion and cracks in low-density materials. Discovering of fatigue cracks and corrosion in piping without the necessity of insulation removal is possible. Neutron radiography sources can provide for the nondestructive testing interests of commercial and military aircraft, public utilities and petrochemical organizations. Three neutron prototype neutron generators were designed and fabricated based on original research done at the Lawrence Berkeley National Laboratory (LBNL). The research and development of these generators was successfully continued by LBNL and Adelphi Technology Inc. under this STTR. The original design goals of high neutron yield and generator robustness have been achieved, using new technology developed under this grant. In one prototype generator, the fast neutron yield and brightness was roughly 10 times larger than previously marketed neutron generators using the same deuterium-deuterium reaction. In another generator, we integrate a moderator with a fast neutron source, resulting in a high brightness thermal neutron generator. The moderator acts as both conventional moderator and mechanical and electrical support structure for the generator and effectively mimics a nuclear reactor. In addition to the new prototype generators, an entirely new plasma ion source for neutron production was developed. First developed by LBNL, this source uses a spiral antenna to more efficiently couple the RF radiation into the plasma, reducing the required gas pressure so that the generator head can be completely sealed, permitting the possible use of tritium gas. This also permits the generator to use the deuterium-tritium reaction to produce 14-MeV neutrons with increases

  12. ACR Appropriateness Criteria(®) acute nonspecific chest pain-low probability of coronary artery disease.

    Science.gov (United States)

    Hoffmann, Udo; Venkatesh, Vikram; White, Richard D; Woodard, Pamela K; Carr, J Jeffrey; Dorbala, Sharmila; Earls, James P; Jacobs, Jill E; Mammen, Leena; Martin, Edward T; Ryan, Thomas; White, Charles S

    2012-10-01

    This document outlines the usefulness of available diagnostic imaging for patients without known coronary artery disease and at low probability for having coronary artery disease who do not present with classic signs, symptoms, or electrocardiographic abnormalities indicating acute coronary syndrome but rather with nonspecific chest pain leading to a differential diagnosis, including pulmonary, gastrointestinal, or musculoskeletal pathologies. A number of imaging modalities are available to evaluate the broad spectrum of possible pathologies in these patients, such as chest radiography, multidetector CT, MRI, ventilation-perfusion scans, cardiac perfusion scintigraphy, transesophageal and transthoracic echocardiography, PET, spine and rib radiography, barium esophageal and upper gastrointestinal studies, and abdominal ultrasound. It is considered appropriate to start the assessment of these patients with a low-cost, low-risk diagnostic test such as a chest x-ray. Contrast-enhanced gated cardiac and ungated thoracic multidetector CT as well as transthoracic echocardiography are also usually considered as appropriate in the evaluation of these patients as a second step if necessary. A number of rest and stress single-photon emission CT myocardial perfusion imaging, ventilation-perfusion scanning, aortic and chest MR angiographic, and more specific x-ray and abdominal examinations may be appropriate as a third layer of testing, whereas MRI of the heart or coronary arteries and invasive testing such as transesophageal echocardiography or selective coronary angiography are not considered appropriate in these patients. Given the low risk of these patients, it is mandated to minimize radiation exposure as much as possible using advanced and appropriate testing protocols. The ACR Appropriateness Criteria® are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review

  13. Relevant surgical anatomy of the chest wall

    OpenAIRE

    Rajesh, Pala Babu; Naidu, Babu V.

    2010-01-01

    The chest wall, like other regional anatomy, is a remarkable fusion of form and function. Principal functions are the protection of internal viscera and an expandable cylinder facilitating variable gas flow into the lungs. Knowledge of the anatomy of the whole cylinder (ribs, sternum, vertebra, diaphragm, intercostal spaces, and extrathoracic muscles) is therefore not only important in the local environment of a specific chest wall resection but also in its relation to overall function. An un...

  14. CARDIOVASCULAR DISORDERS IN ADOLESCENTS WITH CHEST PAIN

    OpenAIRE

    Sri Endah Rahayuningsih; Rahmat Budi; Herry Garna

    2014-01-01

    Objective: To detect cardiovascular abnormalities in adolescents with chest pain. Methods: In this cross sectional study, the subjects were 25 adolescents with chest pain who came to the Cardiac Center of Dr. Hasan Sadikin General Hospital, Bandung during the period of January 2008 to January 2011. The presence of established cardiovascular disorders were based on history, physical examination, electrocardiography and echocardiography Results: It was found that 13/25 adolesce...

  15. Finding on a chest radiograph: A dangerous complication of subclavian vein cannulation

    Directory of Open Acces