Science.gov

Sample records for medical diagnostic ultrasound

  1. Synergistic advances in diagnostic and therapeutic medical ultrasound

    NASA Astrophysics Data System (ADS)

    Lizzi, Frederic L.

    2003-04-01

    Significant advances are more fully exploiting ultrasound's potential for noninvasive diagnosis and treatment. Therapeutic systems employ intense focused beams to thermally kill cancer cells in, e.g., prostate; to stop bleeding; and to treat specific diseases (e.g., glaucoma). Diagnostic ultrasound techniques can quantitatively image an increasingly broad spectrum of physical tissue attributes. An exciting aspect of this progress is the emerging synergy between these modalities. Advanced diagnostic techniques may contribute at several stages in therapy. For example, treatment planning for small ocular tumors uses 50-MHz, 3-D ultrasonic images with 0.05-mm resolution. Thermal simulations employ these images to evaluate desired and undesired effects using exposure stategies with specially designed treatment beams. Therapy beam positioning can use diagnostic elastography to sense tissue motion induced by radiation pressure from high-intensity treatment beams. Therapy monitoring can sense lesion formation using elastography motion sensing (to detect the increased stiffness in lesions); harmonic imaging (to sense altered nonlinear properties); and spectrum analysis images (depicting changes in the sizes, concentration, and configuration of sub-resolution structures.) Experience from these applications will greatly expand the knowledge of acoustic phenomena in living tissues and should lead to further advances in medical ultrasound.

  2. Ultrasound Metrology in Mexico: a round robin test for medical diagnostics

    NASA Astrophysics Data System (ADS)

    Amezola Luna, R.; López Sánchez, A. L.; Elías Juárez, A. A.

    2011-02-01

    This paper presents preliminary statistical results from an on-going imaging medical ultrasound study, of particular relevance for gynecology and obstetrics areas. Its scope is twofold, firstly to compile the medical ultrasound infrastructure available in cities of Queretaro-Mexico, and second to promote the use of traceable measurement standards as a key aspect to assure quality of ultrasound examinations performed by medical specialists. The experimental methodology is based on a round robin test using an ultrasound phantom for medical imaging. The physician, using its own ultrasound machine, couplant and facilities, measures the size and depth of a set of pre-defined reflecting and absorbing targets of the reference phantom, which simulate human illnesses. Measurements performed give the medical specialist an objective feedback regarding some performance characteristics of their ultrasound examination systems, such as measurement system accuracy, dead zone, axial resolution, depth of penetration and anechoic targets detection. By the end of March 2010, 66 entities with medical ultrasound facilities, from both public and private institutions, have performed measurements. A network of medical ultrasound calibration laboratories in Mexico, with traceability to The International System of Units via national measurement standards, may indeed contribute to reduce measurement deviations and thus attain better diagnostics.

  3. Source Book of Educational Materials for Diagnostic Medical Ultrasound. Radiological Health Series.

    ERIC Educational Resources Information Center

    Pijar, Mary Lou, Comp; And Others

    This report is a compilation of educational materials that are available in the field of diagnostic medical ultrasound. Materials, which include publications, audiovisual aids, and teaching aids, are listed under the following categories: abdominal imaging; anatomy and physiology; anatomy and embryology; bioeffects; cardiology and vasculature;…

  4. Visualizing and measuring the temperature field produced by medical diagnostic ultrasound using thermography

    NASA Astrophysics Data System (ADS)

    Vachutka, J.; Grec, P.; Mornstein, V.; Caruana, C. J.

    2008-11-01

    The heating of tissues by diagnostic ultrasound can pose a significant hazard particularly in the imaging of the unborn child. The demonstration of the temperature field in tissue is therefore an important objective in the teaching of biomedical physics to healthcare professionals. The temperature field in a soft tissue model was made visible and measured using thermography. Temperature data from the images were used to investigate the dependence of temperature increase within the model on ultrasound exposure time and distance from the transducer. The experiment will be used within a multi-professional biomedical physics teaching laboratory for enhancing learning regarding the principles of thermography and the thermal effects of ultrasound to medical and healthcare students and also for demonstrating the quantitative use of thermographic imaging to students of biophysics, medical physics and medical technology.

  5. Visualizing and Measuring the Temperature Field Produced by Medical Diagnostic Ultrasound Using Thermography

    ERIC Educational Resources Information Center

    Vachutka, J.; Grec, P.; Mornstein, V.; Caruana, C. J.

    2008-01-01

    The heating of tissues by diagnostic ultrasound can pose a significant hazard particularly in the imaging of the unborn child. The demonstration of the temperature field in tissue is therefore an important objective in the teaching of biomedical physics to healthcare professionals. The temperature field in a soft tissue model was made visible and…

  6. Imaging Systems for Medical Diagnosis: Fundamentals and Technical Solutions - X-Ray Diagnostics- Computed Tomography - Nuclear Medical Diagnostics - Magnetic Resonance Imaging - Ultrasound Technology

    NASA Astrophysics Data System (ADS)

    Krestel, Erich

    1990-10-01

    Erick Krestel, Editor Imaging Systems for Medical Diagnostics This book provides physicians and clinical physicists with detailed information on todya's imaging modalities and assists them in selecting the optimal system for each clinical application. Physicists, engineers and computer specialists engaged in research and development and sales departments will also find this book to be of considerable use. It may also be employed at universities, training centers and in technical seminars. The physiological and physical fundamentals are explained in part 1. The technical solutions contained in part 2 illustrate the numerous possibilities available in x-ray diagnostics, computed tomography, nuclear medical diagnostics, magnetic resonance imaging, sonography and biomagnetic diagnostics. Overview of Contents Physiology of vision Image quality X-ray and gamma radiation X-ray diagnostics Computed tomography Nuclear medical diagnostics Magnetic resonance imaging Sonography Biomagnetic diagnostics

  7. Medical ultrasound imaging.

    PubMed

    Jensen, Jørgen Arendt

    2007-01-01

    The paper gives an introduction to current medical ultrasound imaging systems. The basics of anatomic and blood flow imaging are described. The properties of medical ultrasound and its focusing are described, and the various methods for two- and three-dimensional imaging of the human anatomy are shown. Systems using both linear and non-linear propagation of ultrasound are described. The blood velocity can also be non-invasively visualized using ultrasound and the basic signal processing for doing this is introduced. Examples for spectral velocity estimation, color flow imaging and the new vector velocity images are presented. PMID:17092547

  8. Ultrasound introscopic image quantitative characteristics for medical diagnostics and refinements of physical noise rise reasons

    NASA Astrophysics Data System (ADS)

    Novoselets, Mikhail K.; Radchenko, Sergiy P.; Tsubin, Vitaliy A.; Gridko, Alexander N.

    1994-05-01

    Ultrasound images obtained with a simple sector scan show a granular appearance, called `speckle'. The speckle is the useless property of the ultrasound introskopic images as it mask all small differences of the images. The possibility of the speckle noise reduction by special created filter is analyzed. The computer processing results of ultrasound introskopic thyroid gland images by such filter are presented.

  9. Improving medical diagnostic accuracy of ultrasound Doppler signals by combining neural network models.

    PubMed

    Ubeyli, Elif Derya; Güler, Inan

    2005-07-01

    There are a number of different quantitative models that can be used in a medical diagnostic decision support system including parametric methods (linear discriminant analysis or logistic regression), nonparametric models (k nearest neighbor or kernel density) and several neural network models. The complexity of the diagnostic task is thought to be one of the prime determinants of model selection. Unfortunately, there is no theory available to guide model selection. This paper illustrates the use of combined neural network models to guide model selection for diagnosis of ophthalmic and internal carotid arterial disorders. The ophthalmic and internal carotid arterial Doppler signals were decomposed into time-frequency representations using discrete wavelet transform and statistical features were calculated to depict their distribution. The first-level networks were implemented for the diagnosis of ophthalmic and internal carotid arterial disorders using the statistical features as inputs. To improve diagnostic accuracy, the second-level networks were trained using the outputs of the first-level networks as input data. The combined neural network models achieved accuracy rates which were higher than that of the stand-alone neural network models. PMID:15780863

  10. A proposed new clinical assessment framework for diagnostic medical ultrasound students

    PubMed Central

    2013-01-01

    Current financial pressures within higher education institutions (HEIs) are driving new ways of delivering education and assessment. New technological developments are facilitating opportunities to rethink traditional educational methods and explore more innovative, effective approaches. Set against a background of increasing pressures to integrate technology to enhance learning, both in higher education and the NHS, education is moving towards greater integration of technology. Ultrasound education is an area which is currently being reviewed in many HEIs, as these programmes are expensive to administer for the relatively low numbers of students involved. Within ultrasound education, rigorous assessment of clinical competence is an area which is particularly expensive to undertake, and methods used in many training programmes are potentially unsustainable for HEIs in the current economic climate. In addition, clinical assessment methods used are often criticised for the difficulties encountered in trying to exclude subjectivity from the process, and ensure equity across all assessments. A new framework is therefore proposed, which has recently been accredited within a HEI ultrasound training programme by the Consortium for the Accreditation of Sonographic Education (CASE), and has been piloted during 2013. One of the components of this approach is the incorporation of an ultrasound simulator, which will help to standardise assessments and ensure students are assessed over a range of pathologies, rather than only those randomly presenting on the day of assessment. This paper discusses details of the newly accredited assessment process.

  11. Medical ultrasound systems

    PubMed Central

    Powers, Jeff; Kremkau, Frederick

    2011-01-01

    Medical ultrasound imaging has advanced dramatically since its introduction only a few decades ago. This paper provides a short historical background, and then briefly describes many of the system features and concepts required in a modern commercial ultrasound system. The topics addressed include array beam formation, steering and focusing; array and matrix transducers; echo image formation; tissue harmonic imaging; speckle reduction through frequency and spatial compounding, and image processing; tissue aberration; Doppler flow detection; and system architectures. It then describes some of the more practical aspects of ultrasound system design necessary to be taken into account for today's marketplace. It finally discusses the recent explosion of portable and handheld devices and their potential to expand the clinical footprint of ultrasound into regions of the world where medical care is practically non-existent. Throughout the article reference is made to ways in which ultrasound imaging has benefited from advances in the commercial electronics industry. It is meant to be an overview of the field as an introduction to other more detailed papers in this special issue. PMID:22866226

  12. Medical Ultrasound Imaging.

    ERIC Educational Resources Information Center

    Hughes, Stephen

    2001-01-01

    Explains the basic principles of ultrasound using everyday physics. Topics include the generation of ultrasound, basic interactions with material, and the measurement of blood flow using the Doppler effect. (Author/MM)

  13. Integrated photoacoustic, ultrasound and fluorescence platform for diagnostic medical imaging-proof of concept study with a tissue mimicking phantom

    PubMed Central

    James, Joseph; Murukeshan, Vadakke Matham; Woh, Lye Sun

    2014-01-01

    The structural and molecular heterogeneities of biological tissues demand the interrogation of the samples with multiple energy sources and provide visualization capabilities at varying spatial resolution and depth scales for obtaining complementary diagnostic information. A novel multi-modal imaging approach that uses optical and acoustic energies to perform photoacoustic, ultrasound and fluorescence imaging at multiple resolution scales from the tissue surface and depth is proposed in this paper. The system comprises of two distinct forms of hardware level integration so as to have an integrated imaging system under a single instrumentation set-up. The experimental studies show that the system is capable of mapping high resolution fluorescence signatures from the surface, optical absorption and acoustic heterogeneities along the depth (>2cm) of the tissue at multi-scale resolution (<1µm to <0.5mm). PMID:25071954

  14. 5.4 Magnetic Resonance Imaging, Diagnostic Ultrasound

    NASA Astrophysics Data System (ADS)

    Bernhardt, J. H.

    This document is part of Subvolume A 'Fundamentals and Data in Radiobiology, Radiation Biophysics, Dosimetry and Medical Radiological Protection' of Volume 7 'Medical Radiological Physics' of Landolt-Börnstein - Group VIII 'Advanced Materials and Technologies'. It contains the Section '5.4 Magnetic Resonance Imaging, Diagnostic Ultrasound' of the Chapter '5 Medical Radiological Protection' with the contents:

  15. Ultrasound microscope: the new field in ultrasound diagnostics

    NASA Astrophysics Data System (ADS)

    Novyc'kyy, Victor V.; Lushchyk, Ulyana B.

    2001-06-01

    A device which is a new stage in the development of medical equipment has been developed. The device works as an ultrasound microscope in vivo and provides 4 up to 32 colored histological image. It gives possibility to estimate tissue acoustic density with the help of 4 up to 32 gradation coloring different tissues and enables tissue microcirculation visualization. With the help of the device a doctor can objectify fatty hepatitis and cirrhosis, edema of different organs and tissues as well as microcirculation in organs and tissues (e.g. muscles, myocard and bone system). New promising applications of ultrasound systems in diagnostics and for choosing individual treatment tactics, with pathogenesis being taken into account, may be developed with the help of the device.

  16. Despeckling of Medical Ultrasound Images

    PubMed Central

    Michailovich, Oleg V.; Tannenbaum, Allen

    2013-01-01

    Speckle noise is an inherent property of medical ultrasound imaging, and it generally tends to reduce the image resolution and contrast, thereby reducing the diagnostic value of this imaging modality. As a result, speckle noise reduction is an important prerequisite, whenever ultrasound imaging is used for tissue characterization. Among the many methods that have been proposed to perform this task, there exists a class of approaches that use a multiplicative model of speckled image formation and take advantage of the logarithmical transformation in order to convert multiplicative speckle noise into additive noise. The common assumption made in a dominant number of such studies is that the samples of the additive noise are mutually uncorrelated and obey a Gaussian distribution. The present study shows conceptually and experimentally that this assumption is oversimplified and unnatural. Moreover, it may lead to inadequate performance of the speckle reduction methods. The study introduces a simple preprocessing procedure, which modifies the acquired radio-frequency images (without affecting the anatomical information they contain), so that the noise in the log-transformation domain becomes very close in its behavior to a white Gaussian noise. As a result, the preprocessing allows filtering methods based on assuming the noise to be white and Gaussian, to perform in nearly optimal conditions. The study evaluates performances of three different, nonlinear filters—wavelet denoising, total variation filtering, and anisotropic diffusion—and demonstrates that, in all these cases, the proposed preprocessing significantly improves the quality of resultant images. Our numerical tests include a series of computer-simulated and in vivo experiments. PMID:16471433

  17. Despeckling of medical ultrasound images.

    PubMed

    Michailovich, Oleg V; Tannenbaum, Allen

    2006-01-01

    Speckle noise is an inherent property of medical ultrasound imaging, and it generally tends to reduce the image resolution and contrast, thereby reducing the diagnostic value of this imaging modality. As a result, speckle noise reduction is an important prerequisite, whenever ultrasound imaging is used for tissue characterization. Among the many methods that have been proposed to perform this task, there exists a class of approaches that use a multiplicative model of speckled image formation and take advantage of the logarithmical transformation in order to convert multiplicative speckle noise into additive noise. The common assumption made in a dominant number of such studies is that the samples of the additive noise are mutually uncorrelated and obey a Gaussian distribution. The present study shows conceptually and experimentally that this assumption is oversimplified and unnatural. Moreover, it may lead to inadequate performance of the speckle reduction methods. The study introduces a simple preprocessing procedure, which modifies the acquired radio-frequency images (without affecting the anatomical information they contain), so that the noise in the log-transformation domain becomes very close in its behavior to a white Gaussian noise. As a result, the preprocessing allows filtering methods based on assuming the noise to be white and Gaussian, to perform in nearly optimal conditions. The study evaluates performances of three different, nonlinear filters--wavelet denoising, total variation filtering, and anisotropic diffusion--and demonstrates that, in all these cases, the proposed preprocessing significantly improves the quality of resultant images. Our numerical tests include a series of computer-simulated and in vivo experiments. PMID:16471433

  18. Calibrated parametric medical ultrasound imaging.

    PubMed

    Valckx, F M; Thijsse, J M; van Geemen, A J; Rotteveel, J J; Mullaart, R

    2000-01-01

    The goal of this study was to develop a calibrated on-line technique to extract as much diagnostically-relevant information as possible from conventional video-format echograms. The final aim is to improve the diagnostic potentials of medical ultrasound. Video-output images were acquired by a frame grabber board incorporated in a multiprocessor workstation. Calibration images were obtained from a stable tissue-mimicking phantom with known acoustic characteristics. Using these images as reference, depth dependence of the gray level could fairly be corrected for the transducer performance characteristics, for the observer-dependent equipment settings and for attenuation in the examined tissues. Second-order statistical parameters still displayed some nonconsistent depth dependencies. The results obtained with two echoscanners for the same phantom were different; hence, an a posteriori normalization of clinical data with the phantom data is indicated. Prior to processing of clinical echograms,. the anatomical reflections and echoless voids were removed automatically. The final step in the preprocessing concerned the compensation of the overall attenuation in the tissue. A 'sliding window' processing was then applied to a region of interest (ROI) in the 'back-scan converted' images. A number of first and second order statistical texture parameters and acoustical parameters were estimated in each window and assigned to the central pixel. This procedure results in a set of new 'parametric' images of the ROI, which can be inserted in the original echogram (gray value, color) or presented as a color overlay. A clinical example is presented for illustrating the potentials of the developed technique. Depending on the choice of the parameters, four full resolution calibrated parametric images can be calculated and simultaneously displayed within 5 to 20 seconds. In conclusion, an on-line technique has been developed to estimate acoustic and texture parameters with a reduced

  19. Diagnostic ultrasound exposure in man.

    PubMed

    Gramiak, R

    1975-09-01

    In his review of the AAPM statement on ultrasound, the author feels that allowing "some" research or demonstration on normal persons in the face of cautionary statements on as yet unknown side effects is an inconsistent position. The use of videotapes and the development of simulators hacked by data banks are offered in place of tissue phantoms. PMID:1153790

  20. Virtual Guidance Ultrasound: A Tool to Obtain Diagnostic Ultrasound for Remote Environments

    NASA Technical Reports Server (NTRS)

    Caine,Timothy L.; Martin David S.; Matz, Timothy; Lee, Stuart M. C.; Stenger, Michael B.; Platts, Steven H.

    2012-01-01

    Astronauts currently acquire ultrasound images on the International Space Station with the assistance of real-time remote guidance from an ultrasound expert in Mission Control. Remote guidance will not be feasible when significant communication delays exist during exploration missions beyond low-Earth orbit. For example, there may be as much as a 20- minute delay in communications between the Earth and Mars. Virtual-guidance, a pre-recorded audio-visual tutorial viewed in real-time, is a viable modality for minimally trained scanners to obtain diagnostically-adequate images of clinically relevant anatomical structures in an autonomous manner. METHODS: Inexperienced ultrasound operators were recruited to perform carotid artery (n = 10) and ophthalmic (n = 9) ultrasound examinations using virtual guidance as their only instructional tool. In the carotid group, each each untrained operator acquired two-dimensional, pulsed, and color Doppler of the carotid artery. In the ophthalmic group, operators acquired representative images of the anterior chamber of the eye, retina, optic nerve, and nerve sheath. Ultrasound image quality was evaluated by independent imaging experts. RESULTS: Eight of the 10 carotid studies were judged to be diagnostically adequate. With one exception the quality of all the ophthalmic images were adequate to excellent. CONCLUSION: Diagnostically-adequate carotid and ophthalmic ultrasound examinations can be obtained by untrained operators with instruction only from an audio/video tutorial viewed in real time while scanning. This form of quick-response-guidance, can be developed for other ultrasound examinations, represents an opportunity to acquire important medical and scientific information for NASA flight surgeons and researchers when trained medical personnel are not present. Further, virtual guidance will allow untrained personnel to autonomously obtain important medical information in remote locations on Earth where communication is

  1. Medical Imaging with Ultrasound: Some Basic Physics.

    ERIC Educational Resources Information Center

    Gosling, R.

    1989-01-01

    Discussed are medical applications of ultrasound. The physics of the wave nature of ultrasound including its propagation and production, return by the body, spatial and contrast resolution, attenuation, image formation using pulsed echo ultrasound techniques, measurement of velocity and duplex scanning are described. (YP)

  2. Integrated medical school ultrasound: development of an ultrasound vertical curriculum

    PubMed Central

    2013-01-01

    Background Physician-performed focused ultrasonography is a rapidly growing field with numerous clinical applications. Focused ultrasound is a clinically useful tool with relevant applications across most specialties. Ultrasound technology has outpaced the education, necessitating an early introduction to the technology within the medical education system. There are many challenges to integrating ultrasound into medical education including identifying appropriately trained faculty, access to adequate resources, and appropriate integration into existing medical education curricula. As focused ultrasonography increasingly penetrates academic and community practices, access to ultrasound equipment and trained faculty is improving. However, there has remained the major challenge of determining at which level is integrating ultrasound training within the medical training paradigm most appropriate. Methods The Ohio State University College of Medicine has developed a novel vertical curriculum for focused ultrasonography which is concordant with the 4-year medical school curriculum. Given current evidenced-based practices, a curriculum was developed which provides medical students an exposure in focused ultrasonography. The curriculum utilizes focused ultrasonography as a teaching aid for students to gain a more thorough understanding of basic and clinical science within the medical school curriculum. The objectives of the course are to develop student understanding in indications for use, acquisition of images, interpretation of an ultrasound examination, and appropriate decision-making of ultrasound findings. Results Preliminary data indicate that a vertical ultrasound curriculum is a feasible and effective means of teaching focused ultrasonography. The foreseeable limitations include faculty skill level and training, initial cost of equipment, and incorporating additional information into an already saturated medical school curriculum. Conclusions Focused

  3. Comparison of Thermal Safety Practice Guidelines for Diagnostic Ultrasound Exposures.

    PubMed

    Harris, Gerald R; Church, Charles C; Dalecki, Diane; Ziskin, Marvin C; Bagley, Jennifer E

    2016-02-01

    This article examines the historical evolution of various practice guidelines designed to minimize the possibility of thermal injury during a diagnostic ultrasound examination, including those published by the American Institute of Ultrasound in Medicine, British Medical Ultrasound Society and Health Canada. The guidelines for prenatal/neonatal examinations are in general agreement, but significant differences were found for postnatal exposures. We propose sets of thermal index versus exposure time for these examination categories below which there is reasonable assurance that an examination can be conducted without risk of producing an adverse thermal effect under any scanning conditions. If it is necessary to exceed these guidelines, the occurrence of an adverse thermal event is still unlikely in most situations because of mitigating factors such as transducer movement and perfusion, but the general principle of "as low as reasonably achievable" should be followed. Some limitations of the biological effects studies underpinning the guidelines also are discussed briefly. PMID:26626492

  4. Diagnostic ultrasound: Text and cases. Second edition

    SciTech Connect

    Sarti, D.A.

    1986-01-01

    This is a textbook and reference. New added improvements and features include: approximately 1,000 new scans have been added, increasing the number to almost 1,900; new chapters have been added on the breast, neonatal head, the scrotum, pediatrics, and intraoperative ultrasound, real-time scanning; information updated to keep pace with the technological and diagnostic advances in the field; and an expanded and revised text.

  5. Review of Quantitative Ultrasound: Envelope Statistics and Backscatter Coefficient Imaging and Contributions to Diagnostic Ultrasound.

    PubMed

    Oelze, Michael L; Mamou, Jonathan

    2016-02-01

    Conventional medical imaging technologies, including ultrasound, have continued to improve over the years. For example, in oncology, medical imaging is characterized by high sensitivity, i.e., the ability to detect anomalous tissue features, but the ability to classify these tissue features from images often lacks specificity. As a result, a large number of biopsies of tissues with suspicious image findings are performed each year with a vast majority of these biopsies resulting in a negative finding. To improve specificity of cancer imaging, quantitative imaging techniques can play an important role. Conventional ultrasound B-mode imaging is mainly qualitative in nature. However, quantitative ultrasound (QUS) imaging can provide specific numbers related to tissue features that can increase the specificity of image findings leading to improvements in diagnostic ultrasound. QUS imaging can encompass a wide variety of techniques including spectral-based parameterization, elastography, shear wave imaging, flow estimation, and envelope statistics. Currently, spectral-based parameterization and envelope statistics are not available on most conventional clinical ultrasound machines. However, in recent years, QUS techniques involving spectral-based parameterization and envelope statistics have demonstrated success in many applications, providing additional diagnostic capabilities. Spectral-based techniques include the estimation of the backscatter coefficient (BSC), estimation of attenuation, and estimation of scatterer properties such as the correlation length associated with an effective scatterer diameter (ESD) and the effective acoustic concentration (EAC) of scatterers. Envelope statistics include the estimation of the number density of scatterers and quantification of coherent to incoherent signals produced from the tissue. Challenges for clinical application include correctly accounting for attenuation effects and transmission losses and implementation of QUS on

  6. Recent advances in medical ultrasound

    NASA Astrophysics Data System (ADS)

    Crum, Lawrence

    2014-03-01

    Ultrasound has become one of the most widely used imaging modalities in medicine; yet, before ultrasound-imaging systems became available, high intensity ultrasound was used as early as the 1950s to ablate regions in the brains of human patients. Recently, a variety of novel applications of ultrasound have been developed that include site-specific and ultrasound-mediated drug delivery, acoustocautery, lipoplasty, histotripsy, tissue regeneration, and bloodless surgery, among many others. This lecture will review several new applications of therapeutic ultrasound and address some of the basic scientific questions and future challenges in developing these methods and technologies for general use in our society. We shall particularly emphasize the use of High Intensity Focused Ultrasound (HIFU) in the treatment of benign and malignant tumors.

  7. Signal processing in ultrasound. [for diagnostic medicine

    NASA Technical Reports Server (NTRS)

    Le Croissette, D. H.; Gammell, P. M.

    1978-01-01

    Signal is the term used to denote the characteristic in the time or frequency domain of the probing energy of the system. Processing of this signal in diagnostic ultrasound occurs as the signal travels through the ultrasonic and electrical sections of the apparatus. The paper discusses current signal processing methods, postreception processing, display devices, real-time imaging, and quantitative measurements in noninvasive cardiology. The possibility of using deconvolution in a single transducer system is examined, and some future developments using digital techniques are outlined.

  8. Twofold processing for denoising ultrasound medical images.

    PubMed

    Kishore, P V V; Kumar, K V V; Kumar, D Anil; Prasad, M V D; Goutham, E N D; Rahul, R; Krishna, C B S Vamsi; Sandeep, Y

    2015-01-01

    Ultrasound medical (US) imaging non-invasively pictures inside of a human body for disease diagnostics. Speckle noise attacks ultrasound images degrading their visual quality. A twofold processing algorithm is proposed in this work to reduce this multiplicative speckle noise. First fold used block based thresholding, both hard (BHT) and soft (BST), on pixels in wavelet domain with 8, 16, 32 and 64 non-overlapping block sizes. This first fold process is a better denoising method for reducing speckle and also inducing object of interest blurring. The second fold process initiates to restore object boundaries and texture with adaptive wavelet fusion. The degraded object restoration in block thresholded US image is carried through wavelet coefficient fusion of object in original US mage and block thresholded US image. Fusion rules and wavelet decomposition levels are made adaptive for each block using gradient histograms with normalized differential mean (NDF) to introduce highest level of contrast between the denoised pixels and the object pixels in the resultant image. Thus the proposed twofold methods are named as adaptive NDF block fusion with hard and soft thresholding (ANBF-HT and ANBF-ST). The results indicate visual quality improvement to an interesting level with the proposed twofold processing, where the first fold removes noise and second fold restores object properties. Peak signal to noise ratio (PSNR), normalized cross correlation coefficient (NCC), edge strength (ES), image quality Index (IQI) and structural similarity index (SSIM), measure the quantitative quality of the twofold processing technique. Validation of the proposed method is done by comparing with anisotropic diffusion (AD), total variational filtering (TVF) and empirical mode decomposition (EMD) for enhancement of US images. The US images are provided by AMMA hospital radiology labs at Vijayawada, India. PMID:26697285

  9. Medical ultrasound education for bioengineers

    NASA Astrophysics Data System (ADS)

    Vaezy, Shahram

    2005-04-01

    The widespread adoption of ultrasound technologies in medicine has necessitated the development of educational programs to address the growing demand for trained expertise in both academia and industry. The demand has been especially great in the field of therapeutic ultrasound that has experienced a significant level of research and development activities in the past decade. The applications cover a wide range including cancer treatment, hemorrhage control, cardiac ablation, gene therapy, and cosmetic surgery. A comprehensive educational program in ultrasound is well suited for bioengineering departments at colleges and universities. Our educational program for students in Bioengineering at the University of Washington includes a year-long coursework covering theory and practice of ultrasound, conducting research projects, attending and presenting at weekly seminars on literature survey, presentations at scientific meetings, and attending specialized workshops offered by various institutions for specific topics. An important aspect of this training is its multi-disciplinary approach, encompassing science, engineering, and medicine. The students are required to build teams with expertise in these disciplines. Our experience shows that these students are well prepared for careers in academia, conducting cutting edge research, as well as industry, being involved in the transformation of research end-products to commercially viable technology.

  10. Diagnostic and interventional musculoskeletal ultrasound: part 2. Clinical applications.

    PubMed

    Smith, Jay; Finnoff, Jonathan T

    2009-02-01

    Musculoskeletal ultrasound involves the use of high-frequency sound waves to image soft tissues and bony structures in the body for the purposes of diagnosing pathology or guiding real-time interventional procedures. Recently, an increasing number of physicians have integrated musculoskeletal ultrasound into their practices to facilitate patient care. Technological advancements, improved portability, and reduced costs continue to drive the proliferation of ultrasound in clinical medicine. This increased interest creates a need for education pertaining to all aspects of musculoskeletal ultrasound. The primary purpose of this article is to review diagnostic ultrasound technology and its potential clinical applications in the evaluation and treatment of patients with neurological and musculoskeletal disorders. After reviewing this article, physicians should be able to (1) list the advantages and disadvantages of ultrasound compared to other available imaging modalities; (2) describe how ultrasound machines produce images using sound waves; (3) discuss the steps necessary to acquire and optimize an ultrasound image; (4) understand the difference ultrasound appearances of tendons, nerves, muscles, ligaments, blood vessels, and bones; and (5) identify multiple applications for diagnostic and interventional musculoskeletal ultrasound. Part 2 of this 2-part article will focus on the clinical applications of musculoskeletal ultrasound in clinical practice, including the ultrasonographic appearance of normal and abnormal tissues as well as specific diagnostic and interventional applications in major body regions. PMID:19627890

  11. Enhanced ultrasound for advanced diagnostics, ultrasound tomography for volume limb imaging and prosthetic fitting

    NASA Astrophysics Data System (ADS)

    Anthony, Brian W.

    2016-04-01

    Ultrasound imaging methods hold the potential to deliver low-cost, high-resolution, operator-independent and nonionizing imaging systems - such systems couple appropriate algorithms with imaging devices and techniques. The increasing demands on general practitioners motivate us to develop more usable and productive diagnostic imaging equipment. Ultrasound, specifically freehand ultrasound, is a low cost and safe medical imaging technique. It doesn't expose a patient to ionizing radiation. Its safety and versatility make it very well suited for the increasing demands on general practitioners, or for providing improved medical care in rural regions or the developing world. However it typically suffers from sonographer variability; we will discuss techniques to address user variability. We also discuss our work to combine cylindrical scanning systems with state of the art inversion algorithms to deliver ultrasound systems for imaging and quantifying limbs in 3-D in vivo. Such systems have the potential to track the progression of limb health at a low cost and without radiation exposure, as well as, improve prosthetic socket fitting. Current methods of prosthetic socket fabrication remain subjective and ineffective at creating an interface to the human body that is both comfortable and functional. Though there has been recent success using methods like magnetic resonance imaging and biomechanical modeling, a low-cost, streamlined, and quantitative process for prosthetic cup design and fabrication has not been fully demonstrated. Medical ultrasonography may inform the design process of prosthetic sockets in a more objective manner. This keynote talk presents the results of progress in this area.

  12. Schlieren metrology for high frequency medical ultrasound.

    PubMed

    Zanelli, Claudio I; Howard, Samuel M

    2006-12-22

    The increased use of medical ultrasound above 40 MHz poses the challenge of measuring beam features that may be less than 40 microm. We have successfully used the optical Schlieren technique for transducers operating as high as 110 MHz. After a brief discussion of the technique, results are presented, including comparisons to state-of-the-art hydrophones and wire targets. PMID:16949117

  13. Diagnostic and interventional musculoskeletal ultrasound: part 1. Fundamentals.

    PubMed

    Smith, Jay; Finnoff, Jonathan T

    2009-01-01

    Musculoskeletal ultrasound involves the use of high-frequency sound waves to image soft tissues and bony structures in the body for the purposes of diagnosing pathology or guiding real-time interventional procedures. Recently, an increasing number of physicians have integrated musculoskeletal ultrasound into their practices to facilitate patient care. Technological advancements, improved portability, and reduced costs continue to drive the proliferation of ultrasound in clinical medicine. This increased interest creates a need for education pertaining to all aspects of musculoskeletal ultrasound. The primary purpose of this article is to review diagnostic ultrasound technology and its potential clinical applications in the evaluation and treatment of patients with neurologic and musculoskeletal disorders. After reviewing this article, physicians should be able to (1) list the advantages and disadvantages of ultrasound compared with other available imaging modalities, (2) describe how ultrasound machines produce images using sound waves, (3) discuss the steps necessary to acquire and optimize an ultrasound image, (4) understand the different ultrasound appearances of tendons, nerves, muscles, ligaments, blood vessels, and bones, and (5) identify multiple applications for diagnostic and interventional musculoskeletal ultrasound in musculoskeletal practice. Part 1 of this 2-part article reviews the fundamentals of clinical ultrasonographic imaging, including relevant physics, equipment, training, image optimization, and scanning principles for diagnostic and interventional purposes. PMID:19627875

  14. Era of diagnostic and interventional ultrasound.

    PubMed

    Xu, Hui-Xiong

    2011-05-28

    It is an era of diagnostic and interventional ultrasound (US). Various new techniques such as three-dimensional US (3D US), interventional US, and contrast-enhanced US (CEUS) have been introduced into clinical practice. Dr. Xu and his colleagues have taken advantage of these techniques and carried out a series of relevant studies. Their use of 3D US in the liver, gallbladder, liver tumor volumetry, guidance for ablation, and 3D CEUS has widened the application of 3D US in the clinic. They found that prognosis in patients with hepatocellular carcinoma (HCC) after thermal ablation with curative intent was determined by treatment response to ablation, pretreatment serum AFP, and liver function reserve. Tumor response to treatment was the most predictive factor for long-term survival. They compared the use of percutaneous microwave ablation and radiofrequency ablation for the treatment of HCC and found that both are effective methods in treating HCCs. The local tumor control, complications related to treatment, and long-term survival were equivalent for the two modalities. They first compared the enhancement patterns of HCC and intrahepatic cholangiocarcinoma (ICC) and proposed the diagnostic clues for ICC, liver angiomyolipoma (AML), gallbladder cancer, renal carcinoma, and renal AML, which have greatly enhanced the role of CEUS in the clinic. They also evaluated the diagnostic performance of CEUS in characterizing complex cystic focal liver lesions and the agreement between two investigators with different experience levels; and found that CEUS is especially useful for the young investigator. They assessed the effect of anti-angiogenic gene therapy for HCC treated by microbubble-enhanced US exposure and concluded that gene therapy mediated by US exposure enhanced by a microbubble contrast agent may become a new treatment option for HCC. PMID:21666820

  15. Novel fusion algorithms for medical ultrasound tomography

    NASA Astrophysics Data System (ADS)

    Bashford, Gregory R.; Morse, Jonathan L.; Melander, Jennifer R.

    2004-10-01

    Ultrasound tomography is a bioimaging method that combines the geometry of X-ray computed tomography with the non-ionizing energy of ultrasound. This modality has potential clinical utility in breast cancer screening and diagnosis. In conventional ultrasound tomography, data sets from different interrogation angles are used to reconstruct an estimate of a biomechanical property of the tissue, such as sound velocity, in the form of an image. Here we describe an alternative method of reconstruction using novel algorithms which weight the data based on a "quality" score. The quality score is derived from beamforming characteristics, for example, the weighting of angle-dependent data by its distance from the transmit focal zones. The new approach is that for each data set (taken at a different view angle), the reliability of the data (in the range dimension) is assumed to vary. By fusing (combining) the data based on the quality score, a complete image is formed. In this paper, we describe the construction of a rotational translation stage and tissue-mimicking phantoms that are used in conjunction with a commercial medical ultrasound machine to test our reconstruction algorithms. The new algorithms were found to increase the contrast-to-speckle ratio of simulated cysts by 114% from raw data over a 77% improvement by spatial compounding (averaging), and to decrease wire target width by 54% over a 39% reduction by spatial compounding alone. The new method shows promise as a computationally efficient method of improving contrast and resolution in ultrasound images.

  16. Lung Ultrasound Diagnostic Accuracy in Neonatal Pneumothorax

    PubMed Central

    Copetti, Roberto

    2016-01-01

    Background. Pneumothorax (PTX) still remains a common cause of morbidity in critically ill and ventilated neonates. At the present time, lung ultrasound (LUS) is not included in the diagnostic work-up of PTX in newborns despite of excellent evidence of reliability in adults. The aim of this study was to compare LUS, chest X-ray (CXR), and chest transillumination (CTR) for PTX diagnosis in a group of neonates in which the presence of air in the pleural space was confirmed. Methods. In a 36-month period, 49 neonates with respiratory distress were enrolled in the study. Twenty-three had PTX requiring aspiration or chest drainage (birth weight 2120 ± 1640 grams; gestational age = 36 ± 5 weeks), and 26 were suffering from respiratory distress without PTX (birth weight 2120 ± 1640 grams; gestational age = 34 ± 5 weeks). Both groups had done LUS, CTR, and CXR. Results. LUS was consistent with PTX in all 23 patients requiring chest aspiration. In this group, CXR did not detect PTX in one patient while CTR did not detect it in 3 patients. Sensitivity and specificity in diagnosing PTX were therefore 1 for LUS, 0.96 and 1 for CXR, and 0.87 and 0.96 for CTR. Conclusions. Our results confirm that also in newborns LUS is at least as accurate as CXR in the diagnosis of PTX while CTR has a lower accuracy.

  17. Guideline report. Medical ultrasound imaging: progress and opportunities.

    PubMed

    Burns, M

    1989-01-01

    Utilization of medical ultrasound has expanded rapidly during the past several years. In 1988, sales of ultrasound equipment will approach $600 million, which is higher than any other individual imaging modality, including the most capital intensive, such as magnetic resonance imaging (MRI), computed tomography (CT), and cath lab angiography. This growth would have been difficult to predict previously, since ultrasound appeared to be a relatively mature imaging modality not too long ago. There are several reasons for this growth. Technological developments have been quite rapid; ultrasound has become easier to use, image quality has improved dramatically, and diagnostic accuracy has been enhanced. There has been a proliferation of new equipment at all ends of the price spectrum, allowing the user a wide choice in instrument performance, multi-function capabilities, and automated features to increase patient throughput. The DRG environment and the prospect for more pre-admission tests have also been a stimulus. Hospital buying activity has expanded, and many more ultrasound exams are now being conducted on an outpatient basis. Sales to freestanding imaging centers and individual physicians have similarly increased. The hospital user is willing to pay a large premium for advanced technical performance and is prepared to retire or replace older technology in less than three years. This replacement cycle is much shorter than the four to five year period which existed prior to 1985. By comparison, some of the more traditional imaging areas, such as radiology, have replacement rates of eight to ten years. The reason for early replacement is obvious. Ultrasound exams in hospitals generate revenues at a rate that justifies the purchase of the most advanced equipment. It also improves the referral rate and positions the hospital as a high quality provider. Even with low utilization rates, an ultrasound instrument can normally pay for itself in less than one year of regular

  18. Using Ultrasound to Teach Medical Students Cardiac Physiology

    ERIC Educational Resources Information Center

    Bell, Floyd E., III; Wilson, L. Britt; Hoppmann, Richard A.

    2015-01-01

    Ultrasound is being incorporated more into undergraduate medical education. Studies have shown that medical students have positive perceptions about the value of ultrasound in teaching courses like anatomy and physiology. The purpose of the present study was to provide objective evidence of whether ultrasound helps students learn cardiac…

  19. Diagnostic ultrasound and telemedicine utilization in the international space station

    NASA Astrophysics Data System (ADS)

    Carter, Stephen J.; Stewart, Brent K.; Kushmerick, Martin J.; Langer, Steve G.; Schmiedl, Udo P.; Winter, Thomas C.; Conley, Kevin E.; Jubrias, Sharon A.

    1999-01-01

    Clinical diagnostic ultrasound (US) is experiencing an expanding role that is well suited to application on the International Space Station (ISS). Diagnostic US can be used to reduce the risks associated with long duration human space flight by providing a non-invasive tool with head-to-toe diagnostic capability in both biomedical research and crew health care. General health care of the astronauts will be diagnosed with US, e.g., kidney stones, gall bladder disease, appendicitis, etc. Initial studies will focus on detection of ``ureteral jets'' in the bladder. This is a non-invasive test to rule out obstructive uropathy from kidney stones with minimal requirements for crew training. Biomedical research experiments, focusing on the effects of the microgravity environment, will be performed using both the HHU and the HDI 5000. US will be used to evaluate bone density and muscle mass in this environment. Prolonged or emergency EVAs may occur with the ISS. The hand-held ultrasound unit (HHU) and its telemedicine capability will be used in EVA settings to monitor events such as decompression sickness (DCS) microbubble formation in the cardiovascular system. There will be telemetry links between the HHU and the ATL/Lockheed Martin rack mounted HDI 5000 in the ISS Human Research Facility (HRF), as well as between the HRF and medical expertise on the ground. These links will provide the ISS with both real-time and store-and-forward telemedicine capabilities. The HHU can also be used with the existing telemedicine instrument pack (TIP).

  20. Wireless medical ultrasound video transmission through noisy channels.

    PubMed

    Panayides, A; Pattichis, M S; Pattichis, C S

    2008-01-01

    Recent advances in video compression such as the current state-of-the-art H.264/AVC standard in conjunction with increasingly available bitrate through new technologies like 3G, and WiMax have brought mobile health (m-Health) healthcare systems and services closer to reality. Despite this momentum towards m-Health systems and especially e-Emergency systems, wireless channels remain error prone, while the absence of objective quality metrics limits the ability of providing medical video of adequate diagnostic quality at a required bitrate. In this paper we investigate different encoding schemes and loss rates in medical ultrasound video transmission and come to conclusions involving efficiency, the trade-off between bitrate and quality, while we highlight the relationship linking video quality and the error ratio of corrupted P and B frames. More specifically, we investigate IPPP, IBPBP and IBBPBBP coding structures under packet loss rates of 2%, 5%, 8% and 10% and derive that the latter attains higher SNR ratings in all tested cases. A preliminary clinical evaluation shows that for SNR ratings higher than 30 db, video diagnostic quality may be adequate, while above 30.5 db the diagnostic information available in the reconstructed ultrasound video is close to that of the original. PMID:19163920

  1. Resolution enhancement in medical ultrasound imaging

    PubMed Central

    Ploquin, Marie; Basarab, Adrian; Kouamé, Denis

    2015-01-01

    Abstract. Image resolution enhancement is a problem of considerable interest in all medical imaging modalities. Unlike general purpose imaging or video processing, for a very long time, medical image resolution enhancement has been based on optimization of the imaging devices. Although some recent works purport to deal with image postprocessing, much remains to be done regarding medical image enhancement via postprocessing, especially in ultrasound imaging. We face a resolution improvement issue in the case of medical ultrasound imaging. We propose to investigate this problem using multidimensional autoregressive (AR) models. Noting that the estimation of the envelope of an ultrasound radio frequency (RF) signal is very similar to the estimation of classical Fourier-based power spectrum estimation, we theoretically show that a domain change and a multidimensional AR model can be used to achieve super-resolution in ultrasound imaging provided the order is estimated correctly. Here, this is done by means of a technique that simultaneously estimates the order and the parameters of a multidimensional model using relevant regression matrix factorization. Doing so, the proposed method specifically fits ultrasound imaging and provides an estimated envelope. Moreover, an expression that links the theoretical image resolution to both the image acquisition features (such as the point spread function) and a postprocessing feature (the AR model) order is derived. The overall contribution of this work is threefold. First, it allows for automatic resolution improvement. Through a simple model and without any specific manual algorithmic parameter tuning, as is used in common methods, the proposed technique simply and exclusively uses the ultrasound RF signal as input and provides the improved B-mode as output. Second, it allows for the a priori prediction of the improvement in resolution via the knowledge of the parametric model order before actual processing. Finally, to achieve

  2. Optoelectronic tweezers for medical diagnostics

    NASA Astrophysics Data System (ADS)

    Kremer, Clemens; Neale, Steven; Menachery, Anoop; Barrett, Mike; Cooper, Jonathan M.

    2012-01-01

    Optoelectronic tweezers (OET) allows the spatial patterning of electric fields through selected illumination of a photoconductive surface. This enables the manipulation of micro particles and cells by creating non-uniform electrical fields that then produce dielectrophoretic (DEP) forces. The DEP responses of cells differ and can produce negative or positive (repelled or attracted to areas of high electric field) forces. Therefore OET can be used to manipulate individual cells and separate different cell types from each other. Thus OET has many applications for medical diagnostics, demonstrated here with work towards diagnosing Human African Trypanosomiasis, also known as sleeping sickness.

  3. Diagnostic ultrasound at MACH 20: retroperitoneal and pelvic imaging in space.

    PubMed

    Jones, J A; Sargsyan, A E; Barr, Y R; Melton, S; Hamilton, D R; Dulchavsky, S A; Whitson, P A

    2009-07-01

    An operationally available diagnostic imaging capability augments spaceflight medical support by facilitating the diagnosis, monitoring and treatment of medical or surgical conditions, by improving medical outcomes and, thereby, by lowering medical mission impacts and the probability of crew evacuation due to medical causes. Microgravity-related physiological changes occurring during spaceflight can affect the genitourinary system and potentially cause conditions such as urinary retention or nephrolithiasis for which ultrasonography (U/S) would be a useful diagnostic tool. This study describes the first genitourinary ultrasound examination conducted in space, and evaluates image quality, frame rate, resolution requirements, real-time remote guidance of nonphysician crew medical officers and evaluation of on-orbit tools that can augment image acquisition. A nonphysician crew medical officer (CMO) astronaut, with minimal training in U/S, performed a self-examination of the genitourinary system onboard the International Space Station, using a Philips/ATL Model HDI-5000 ultrasound imaging unit located in the International Space Station Human Research Facility. The CMO was remotely guided by voice commands from experienced, earth-based sonographers stationed in Mission Control Center in Houston. The crewmember, with guidance, was able to acquire all of the target images. Real-time and still U/S images received at Mission Control Center in Houston were of sufficient quality for the images to be diagnostic for multiple potential genitourinary applications. Microgravity-based ultrasound imaging can provide diagnostic quality images of the retroperitoneum and pelvis, offering improved diagnosis and treatment for onboard medical contingencies. Successful completion of complex sonographic examinations can be obtained even with minimally trained nonphysician ultrasound operators, with the assistance of ground-based real-time guidance. PMID:19427106

  4. Neonatal urological ultrasound: diagnostic inaccuracies and pitfalls.

    PubMed Central

    Clarke, N W; Gough, D C; Cohen, S J

    1989-01-01

    Ninety one patients with urinary tract abnormalities diagnosed before birth were reviewed. Diagnoses based on prenatal and postnatal ultrasound scans alone were compared with the final diagnoses after full urological investigations, with operative or necropsy confirmation in 79 cases. The results confirmed that ultrasound examination before birth usually detects nonspecific abnormalities and although scanning after birth is more accurate it is not absolutely reliable. A diagnosis of "multicystic kidney' made on ultrasound scan alone is especially prone to error. Such mistakes can be avoided if full urological investigation is undertaken in every case. PMID:2665660

  5. Evaluation of various speckle reduction filters on medical ultrasound images.

    PubMed

    Wu, Shibin; Zhu, Qingsong; Xie, Yaoqin

    2013-01-01

    At present, ultrasound is one of the essential tools for noninvasive medical diagnosis. However, speckle noise is inherent in medical ultrasound images and it is the cause for decreased resolution and contrast-to-noise ratio. Low image quality is an obstacle for effective feature extraction, recognition, analysis, and edge detection; it also affects image interpretation by doctor and the accuracy of computer-assisted diagnostic techniques. Thus, speckle reduction is significant and critical step in pre-processing of ultrasound images. Many speckle reduction techniques have been studied by researchers, but to date there is no comprehensive method that takes all the constraints into consideration. In this paper we discuss seven filters, namely Lee, Frost, Median, Speckle Reduction Anisotropic Diffusion (SRAD), Perona-Malik's Anisotropic Diffusion (PMAD) filter, Speckle Reduction Bilateral Filter (SRBF) and Speckle Reduction filter based on soft thresholding in the Wavelet transform. A comparative study of these filters has been made in terms of preserving the features and edges as well as effectiveness of de-noising.We computed five established evaluation metrics in order to determine which despeckling algorithm is most effective and optimal for real-time implementation. In addition, the experimental results have been demonstrated by filtered images and statistical data table. PMID:24109896

  6. Phased-array ultrasound technology enhances accuracy of dual frequency ultrasound measurements - towards improved ultrasound bone diagnostics.

    PubMed

    Linder, Hans; Malo, Markus K H; Liukkonen, Jukka; Jurvelin, Jukka S; Töyräs, Juha

    2016-08-01

    Overlying soft tissues attenuate ultrasound backscattered from bone, complicating diagnostics of osteoporosis at the most important fracture sites. Dual-frequency ultrasound technique (DFUS) has been proposed to solve this problem through determination of thickness and composition of overlying soft tissue. This study applies DFUS technique for the first time with a phased-array transducer to investigate if the thickness of two interfering layers (oil and water) can be accurately determined in a variety of configurations. Results indicate that DFUS may be used with phased-array ultrasound systems, making them a suitable combination to consider in future development of clinical in vivo ultrasound methodologies. PMID:27187271

  7. American Medical Society for Sports Medicine recommended sports ultrasound curriculum for sports medicine fellowships.

    PubMed

    Finnoff, Jonathan T; Berkoff, David; Brennan, Fred; DiFiori, John; Hall, Mederic M; Harmon, Kimberly; Lavallee, Mark; Martin, Sean; Smith, Jay; Stovak, Mark

    2015-02-01

    The American Medical Society for Sports Medicine (AMSSM) developed a musculoskeletal ultrasound curriculum for sports medicine fellowships in 2010. As the use of diagnostic and interventional ultrasound in sports medicine has evolved, it became clear that the curriculum needed to be updated. Furthermore, the name 'musculoskeletal ultrasound' was changed to 'sports ultrasound' (SPORTS US) to reflect the broad range of diagnostic and interventional applications of ultrasound in sports medicine. This document was created to outline the core competencies of SPORTS US and to provide sports medicine fellowship directors and others interested in SPORTS US education with a guide to create a SPORTS US curriculum. By completing this SPORTS US curriculum, sports medicine fellows and physicians can attain proficiency in the core competencies of SPORTS US required for the practice of sports medicine. PMID:25361787

  8. EFSUMB statement on medical student education in ultrasound [short version].

    PubMed

    Cantisani, V; Dietrich, C F; Badea, R; Dudea, S; Prosch, H; Cerezo, E; Nuernberg, D; Serra, A L; Sidhu, P S; Radzina, M; Piscaglia, F; Bachmann Nielsen, M; Calliada, F; Gilja, O H

    2016-02-01

    The European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB) recommends that ultrasound should be used systematically as an easy accessible and instructive educational tool in the curriculum of modern medical schools. Medical students should acquire theoretical knowledge of the modality and hands-on training should be implemented and adhere to evidence-based principles. In this paper we summarise EFSUMB policy statements on medical student education in ultrasound. PMID:26871409

  9. Assessing the Risks for Modern Diagnostic Ultrasound Imaging

    NASA Astrophysics Data System (ADS)

    William, Jr.

    1998-05-01

    Some 35 years after Paul-Jacques and Pierre Curie discovered piezoelectricity, ultrasonic imaging was developed by Paul Langevin. During this work, ultrasonic energy was observed to have a detrimental biological effect. These observations were confirmed a decade later by R. W. Wood and A. L. Loomis. It was not until the early 1950s that ultrasonic exposure conditions were controlled and specified so that studies could focus on the mechanisms by which ultrasound influenced biological materials. In the late 1940s, pioneering work was initiated to image the human body by ultrasonic techniques. These engineers and physicians were aware of the deleterious ultrasound effects at sufficiently high levels; this endeavored them to keep the exposure levels reasonably low. Over the past three decades, diagnostic ultrasound has become a sophisticated technology. Yet, our understanding of the potential risks has not changed appreciably. It is very encouraging that human injury has never been attributed to clinical practice of diagnostic ultrasound.

  10. Uncertainty evaluation of dead zone of diagnostic ultrasound equipment

    NASA Astrophysics Data System (ADS)

    Souza, R. M.; Alvarenga, A. V.; Braz, D. S.; Petrella, L. I.; Costa-Felix, R. P. B.

    2016-07-01

    This paper presents a model for evaluating measurement uncertainty of a feature used in the assessment of ultrasound images: dead zone. The dead zone was measured by two technicians of the INMETRO's Laboratory of Ultrasound using a phantom and following the standard IEC/TS 61390. The uncertainty model was proposed based on the Guide to the Expression of Uncertainty in Measurement. For the tested equipment, results indicate a dead zone of 1.01 mm, and based on the proposed model, the expanded uncertainty was 0.17 mm. The proposed uncertainty model contributes as a novel way for metrological evaluation of diagnostic imaging by ultrasound.

  11. Characterization of various tissue mimicking materials for medical ultrasound imaging

    NASA Astrophysics Data System (ADS)

    Thouvenot, Audrey; Poepping, Tamie; Peters, Terry M.; Chen, Elvis C. S.

    2016-04-01

    Tissue mimicking materials are physical constructs exhibiting certain desired properties, which are used in machine calibration, medical imaging research, surgical planning, training, and simulation. For medical ultrasound, those specific properties include acoustic propagation speed and attenuation coefficient over the diagnostic frequency range. We investigated the acoustic characteristics of polyvinyl chloride (PVC) plastisol, polydimethylsiloxane (PDMS), and isopropanol using a time-of-light technique, where a pulse was passed through a sample of known thickness contained in a water bath. The propagation speed in PVC is approximately 1400ms-1 depending on the exact chemical composition, with the attenuation coefficient ranging from 0:35 dB cm-1 at 1MHz to 10:57 dB cm-1 at 9 MHz. The propagation speed in PDMS is in the range of 1100ms-1, with an attenuation coefficient of 1:28 dB cm-1 at 1MHz to 21:22 dB cm-1 at 9 MHz. At room temperature (22 °C), a mixture of water-isopropanol (7:25% isopropanol by volume) exhibits a propagation speed of 1540ms-1, making it an excellent and inexpensive tissue-mimicking liquid for medical ultrasound imaging.

  12. High definition ultrasound imaging for battlefield medical applications

    SciTech Connect

    Kwok, K.S.; Morimoto, A.K.; Kozlowski, D.M.; Krumm, J.C.; Dickey, F.M.; Rogers, B; Walsh, N.

    1996-06-23

    A team has developed an improved resolution ultrasound system for low cost diagnostics. This paper describes the development of an ultrasound based imaging system capable of generating 3D images showing surface and subsurface tissue and bone structures. We include results of a comparative study between images obtained from X-Ray Computed Tomography (CT) and ultrasound. We found that the quality of ultrasound images compares favorably with those from CT. Volumetric and surface data extracted from these images were within 7% of the range between ultrasound and CT scans. We also include images of porcine abdominal scans from two different sets of animal trials.

  13. Unilateral Opening of Rat Blood-Brain Barrier Assisted by Diagnostic Ultrasound Targeted Microbubbles Destruction.

    PubMed

    Xu, Yali; Cui, Hai; Zhu, Qiong; Hua, Xing; Xia, Hongmei; Tan, Kaibin; Gao, Yunhua; Zhao, Jing; Liu, Zheng

    2016-01-01

    Objective. Blood-brain barrier (BBB) is a key obstacle that prevents the medication from blood to the brain. Microbubble-enhanced cavitation by focused ultrasound can open the BBB and proves to be valuable in the brain drug delivery. The study aimed to explore the feasibility, efficacy, and safety of unilateral opening of BBB using diagnostic ultrasound targeted microbubbles destruction in rats. Methods. A transtemporal bone irradiation of diagnostic ultrasound and intravenous injection of lipid-coated microbubbles were performed at unilateral hemisphere. Pathological changes were monitored. Evans Blue extravasation grades, extraction from brain tissue, and fluorescence optical density were quantified. Lanthanum nitrate was traced by transmission electron microscopy. Results. After diagnostic ultrasound mediated microbubbles destruction, Evans Blue extravasation and fluorescence integrated optical density were significantly higher in the irradiated hemisphere than the contralateral side (all p < 0.01). Erythrocytes extravasations were demonstrated in the ultrasound-exposed hemisphere (4 ± 1, grade 2) while being invisible in the control side. Lanthanum nitrate tracers leaked through interendothelial cleft and spread to the nerve fiber existed in the irradiation side. Conclusions. Transtemporal bone irradiation under DUS mediated microbubble destruction provides us with a more accessible, safer, and higher selective BBB opening approach in rats, which is advantageous in brain targeted drugs delivery. PMID:27579317

  14. Unilateral Opening of Rat Blood-Brain Barrier Assisted by Diagnostic Ultrasound Targeted Microbubbles Destruction

    PubMed Central

    Cui, Hai; Zhu, Qiong; Hua, Xing; Xia, Hongmei; Tan, Kaibin; Gao, Yunhua; Zhao, Jing

    2016-01-01

    Objective. Blood-brain barrier (BBB) is a key obstacle that prevents the medication from blood to the brain. Microbubble-enhanced cavitation by focused ultrasound can open the BBB and proves to be valuable in the brain drug delivery. The study aimed to explore the feasibility, efficacy, and safety of unilateral opening of BBB using diagnostic ultrasound targeted microbubbles destruction in rats. Methods. A transtemporal bone irradiation of diagnostic ultrasound and intravenous injection of lipid-coated microbubbles were performed at unilateral hemisphere. Pathological changes were monitored. Evans Blue extravasation grades, extraction from brain tissue, and fluorescence optical density were quantified. Lanthanum nitrate was traced by transmission electron microscopy. Results. After diagnostic ultrasound mediated microbubbles destruction, Evans Blue extravasation and fluorescence integrated optical density were significantly higher in the irradiated hemisphere than the contralateral side (all p < 0.01). Erythrocytes extravasations were demonstrated in the ultrasound-exposed hemisphere (4 ± 1, grade 2) while being invisible in the control side. Lanthanum nitrate tracers leaked through interendothelial cleft and spread to the nerve fiber existed in the irradiation side. Conclusions. Transtemporal bone irradiation under DUS mediated microbubble destruction provides us with a more accessible, safer, and higher selective BBB opening approach in rats, which is advantageous in brain targeted drugs delivery. PMID:27579317

  15. Medical ultrasound - From inner space to outer space

    NASA Technical Reports Server (NTRS)

    Rooney, J. A.

    1984-01-01

    During the last decade, medical ultrasound has rapidly become a widely accepted imaging modality used in many medical specialties. It has the advantages that it is noninvasive, does not use ionizing radiation, is relatively inexpensive and is easy to use. Future trends in ultrasound include expanded areas of use, advanced signal processing and digital image analysis including tissue characterization and three-dimensional reconstructions.

  16. Ethical analysis of non-medical fetal ultrasound.

    PubMed

    Leung, John Lai Yin; Pang, Samantha Mei Che

    2009-09-01

    Obstetric ultrasound is the well-recognized prenatal test used to visualize and determine the condition of a pregnant woman and her fetus. Apart from the clinical application, some businesses have started promoting the use of fetal ultrasound machines for nonmedical reasons. Non-medical fetal ultrasound (also known as 'keepsake' ultrasound) is defined as using ultrasound to view, take a picture, or determine the sex of a fetus without a medical indication. Notwithstanding the guidelines and warnings regarding ultrasound safety issued by governments and professional bodies, the absence of scientifically proven physical harm to fetuses from this procedure seems to provide these businesses with grounds for rapid expansion. However, this argument is too simplistic because current epidemiological evidence is not synchronous with advancing ultrasound technology. As non-medical fetal ultrasound has aroused very significant public attention, a thorough ethical analysis of this topic is essential. Using a multifaceted approach, we analyse the ethical perspective of non-medical fetal ultrasound in terms of the expectant mother, the fetus and health professionals. After applying four major theories of ethics and principles (the precautionary principle; theories of consequentialism and impartiality; duty-based theory; and rights-based theories), we conclude that obstetric ultrasound practice is ethically justifiable only if the indication for its use is based on medical evidence. Non-medical fetal ultrasound can be considered ethically unjustifiable. Nevertheless, the ethical analysis of this issue is time dependent owing to rapid advancements in ultrasound technology and the safety issue. The role of health professionals in ensuring that obstetric ultrasound is an ethically justifiable practice is also discussed. PMID:19671649

  17. Induction of pulmonary hemorrhage in rats during diagnostic ultrasound.

    PubMed

    Miller, Douglas L

    2012-08-01

    The induction of pulmonary hemorrhage by pulsed ultrasound was discovered over 20 years ago. This phenomenon may pose a risk of patient lung injury, particularly for point of care pulmonary ultrasound. A diagnostic ultrasound machine (HDI 5000; Philips Healthcare, Andover MA USA) with 7.6 MHz (CL15-7) linear array was used to image the right lung of anesthetized rats in a warmed water bath. The image showed rapid initiation and progression of comet tail artifacts across the lung image for an on-screen mechanical index (MI) of 0.9, which corresponded to a pulmonary hemorrhage in the lung. Groups of rats were scanned at a range of MI settings and a threshold was located at an MI of about 0.44. This finding indicated a greater sensitivity to pulmonary ultrasound than was expected, based on previous results. Further research is needed to understand this phenomenon and to develop safety guidelines for sonographers. PMID:22698500

  18. Heating of fetal bone by diagnostic ultrasound

    NASA Astrophysics Data System (ADS)

    Doody, Claire

    Most pregnant women in the Western world undergo an ultrasound examination and so it is important to ensure that exposure of the embryo or fetus does not produce unwanted effects. It is known that ultrasound can heat tissue, especially bone, and so this thesis explores the degree to which fetal bone might be heated during a pulsed Doppler examination. This is done both by carrying out measurements and by developing computer models. Thermal measurements on human fetal thoracic vertebrae of gestational age ranging from 14 to 39 weeks are reported. The bone samples were insonated in vitro with an ultrasound beam which had power and intensity values typical of those from a clinical scanner operating in pulsed Doppler mode. Temperature rises ranging from 0.6°C to 1.8°C were observed after five minutes, with approximately 75% of the temperature rise occurring in the first minute. Two approaches to computer modelling are described. These are the heated disc technique, which is commonly used to model the temperature rise generated by an ultrasound beam, and finite element modelling, a more general approach used to obtain solutions to differential equations. The degree to which our limited knowledge of the properties of fetal tissue affect our ability to make accurate predictions of in vivo heating is explored. It is shown that the present uncertainty in the value of the thermal conductivity and attenuation coefficient of fetal bone can lead to significant uncertainty in predictions of heating. The degree to which the simplifications inherent in the heated disc model affect the results will also be discussed. The results from the models are compared with the experimental measurements in order to estimate the attenuation coefficient of the bone.

  19. Diagnostic Imaging in the Medical Support of the Future Missions to the Moon

    NASA Technical Reports Server (NTRS)

    Sargsyan, Ashot E.; Jones, Jeffrey A.; Hamilton, Douglas R.; Dulchavsky, Scott A.; Duncan, J. Michael

    2007-01-01

    This viewgraph presentation is a course that reviews the diagnostic imaging techniques available for medical support on the future moon missions. The educational objectives of the course are to: 1) Update the audience on the curreultrasound imaging in space flight; 2) Discuss the unique aspects of conducting ultrasound imaging on ISS, interplanetary transit, ultrasound imaging on ISS, interplanetary transit, and lunar surface operations; and 3) Review preliminary data obtained in simulations of medical imaging in lunar surface operations.

  20. Chest Ultrasound Integrated Teaching of Respiratory System Physiology to Medical Students: A First Experience

    ERIC Educational Resources Information Center

    Paganini, M.; Rubini, A.

    2015-01-01

    Ultrasound imaging is a useful diagnostic technique that has spread among several different medical specialties within the last few years. Initially restricted to radiology, cardiology, obstetrics, and gynecology, today it is widely used by many specialists, especially in critical care. New graduate physicians will need to be comfortable with…

  1. The ultrasound challenge 2.0: introducing interinstitutional competition in medical student ultrasound education.

    PubMed

    Cortez, Eric J; Boulger, Creagh T; Eastin, Travis; Adkins, Eric J; Granitto, Emily; Pollard, Katherine; Bahner, David P

    2014-12-01

    The Ultrasound Challenge was developed at The Ohio State University College of Medicine to introduce focused ultrasound to medical students. The goal was to develop experience in ultrasound through practice and competition. Initially this competition was held between Ohio State University College of Medicine students from years 1 through 4. The Ultrasound Challenge 2.0 was held in 2013. The event expanded on the previous structure by including students from the Wayne State University College of Medicine. The goal of this article is to describe our experiences with expansion of our interinstitutional ultrasound event. The challenge consisted of 6 stations: focused assessment with sonography for trauma, aortic ultrasound, cardiac ultrasound, pelvic ultrasound, musculoskeletal ultrasound, and vascular access. The participants were given a handbook outlining the expectations for each station ahead of time. Vascular access was graded in real time using the Brightness Mode Quality Ultrasound Imaging Examination Technique (B-QUIET) method. The remainder were timed, saved, and graded after the event by 3 independent faculty members using the B-QUIET method. The highest score with the fastest time was the winner. The Ultrasound Challenge 2.0 included 40 participants: 31 from The Ohio State University College of Medicine and 9 from the Wayne State University College of Medicine. The makeup of the winners in all categories consisted of 1 first-year medical student, 7 second-year medical students, 3 third-year medical students, and 10 fourth-year medical students. The Ultrasound Challenge 2.0 was a success for those who participated. It provided the first known interinstitutional medical student ultrasound competition. Students from both institutions were able to practice their image acquisition skills, demonstrate abilities in a competitive environment, and develop collegiality and teamwork. PMID:25425378

  2. Use of smart materials in medical diagnostics

    NASA Astrophysics Data System (ADS)

    Winzer, Stephen R.; Bridger, Keith; Caldwell, Paul J.; Sewell, James S.

    1996-05-01

    Medical diagnostic capabilities have seen explosive growth over the past decade, as new techniques, such as MRI, have been taken from the laboratory setting into the clinical environment, with considerable benefit to the population at large. In this paper, we address another area of medical diagnostics which, we believe, stands on the verge of explosive growth, driven more by the emerging requirements for cost-effective diagnostic tools, and by the evolving needs of the defense medical community, with spinoff of those into the strongly related emergency care area of the civilian market. One of the factors that will drive this area of medical diagnostics is the development of smart materials and the sensors and sensor systems developed from them. In this paper we discuss some of the developments in the field of smart materials as they apply to development of new, low cost acoustic sensors for patient monitoring and medical imaging.

  3. 75 FR 35439 - Medical Diagnostic Equipment Accessibility Standards

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-22

    ... TRANSPORTATION BARRIERS COMPLIANCE BOARD Medical Diagnostic Equipment Accessibility Standards AGENCY... consultation with the Food and Drug Administration, to issue accessibility standards for medical diagnostic... accessibility needs of individuals with disabilities with respect to medical diagnostic equipment and...

  4. Diagnostic and therapeutic research on ultrasound microbubble/nanobubble contrast agents (Review).

    PubMed

    Ma, Jing; Xu, Chang Song; Gao, Feng; Chen, Ming; Li, Fan; Du, Lian Fang

    2015-09-01

    The contrast enhanced imaging function of ultrasound contrast agents (UCAs) has been extensively investigated using physical acoustic signatures. It has a number of novel applications, including tissue‑specific molecular imaging and multi‑modal imaging. In addition there are numerous other therapeutic applications of UCAs, for example as vehicles for drug or gene delivery. These uses are discussed, as well as the acoustically‑induced biological effects, including ultrasound targeted microbubble destruction (UTMD). This review also explores the considerations for the safe use of UCA from an acoustic standpoint. The scope of the application of UCA has markedly expanded in recent years, and it is a rapidly growing field of medical research. The current article reviews recent advances in the diagnostic and therapeutic applications of ultrasound microbubble/nanobubble contrast agents. PMID:26081968

  5. Noninvasive Medical Diagnostics & Treatment Using Ultrasonics

    NASA Technical Reports Server (NTRS)

    Bar-Cohen, Y.; Siegel, R.; Grandia, W.

    1998-01-01

    In parallel to the industrial application of NDE to flaw detection and material property determination, the medical community has succesfully adapted such methods to the noninvasaive diagnostics and treatment of many conditions and disorders of the human body.

  6. Diagnostic Medical Sonographers: Seeing with Sound.

    ERIC Educational Resources Information Center

    Lacey, Alan

    2001-01-01

    Explains how diagnostic medical sonographers use special equipment to direct high frequency sound waves into areas of a patient's body. Describes specialties within the occupation, working conditions, employment and outlook, earnings, and necessary training and qualifications. (JOW)

  7. Bone Composition Diagnostics: Photoacoustics Versus Ultrasound

    NASA Astrophysics Data System (ADS)

    Yang, Lifeng; Lashkari, Bahman; Mandelis, Andreas; Tan, Joel W. Y.

    2015-06-01

    Ultrasound (US) backscatter from bones depends on the mechanical properties and the microstructure of the interrogated bone. On the other hand, photoacoustics (PA) is sensitive to optical properties of tissue and can detect composition variation. Therefore, PA can provide complementary information about bone health and integrity. In this work, a comparative study of US backscattering and PA back-propagating signals from animal trabecular bones was performed. Both methods were applied using a linear frequency modulation chirp and matched filtering. A 2.2 MHz ultrasonic transducer was employed to detect both signals. The use of the frequency domain facilitates spectral analysis. The variation of signals shows that in addition to sensitivity to mineral changes, PA exhibits sensitivity to changes in the organic part of the bone. It is, therefore, concluded that the combination of both modalities can provide complementary detailed information on bone health than either method separately. In addition, comparison of PA and US depthwise images shows the higher penetration of US. Surface scan images exhibit very weak correlation between US and PA which could be caused by the different signal generation origins in mechanical versus optical properties, respectively.

  8. The Dependence of Thresholds for Pulmonary Capillary Hemorrhage on Diagnostic Ultrasound Frequency

    PubMed Central

    Miller, Douglas L.; Dou, Chunyan; Raghavendran, Krishnan

    2015-01-01

    Pulmonary ultrasound examination has become routine for diagnosis in many clinical and point-of-care medical settings. However, the phenomenon of pulmonary capillary hemorrhage (PCH) induction during diagnostic ultrasound imaging presents a poorly understood risk factor. PCH was observed for 1.5 MHz, 4.5 MHz and 12.0 MHz diagnostic ultrasound of anesthetized rats to investigate the frequency dependence of PCH thresholds. PCH was detected in the ultrasound images as growing comet tail artifacts, and assessed using photographs of the surface of excised lungs. Previous photographs acquired with 7.6 MHz diagnostic ultrasound were also included for analysis. In addition, dosimetric parameters were measured at each frequency, including peak rarefactional pressure amplitudes (PRPA) and spatial peak pulse-average (SPPA) intensities attenuated by rat chest-wall samples. PRPA thresholds were determined at each frequency, based on the proportion of PCH occurrence in groups of 5 rats, and were 1.03 ± 0.02 MPa, 1.28 ± 0.14 MPa, 1.18 ± 0.12 MPa and 1.36 ± 0.15 MPa at 1.5, 4.5, 7.6 and 12.0 MHz, respectively. Although the PCH lesions decreased in size with increasing ultrasonic frequency, owing to the smaller beam widths and scan lengths, the PRPA thresholds remained approximately constant. This dependence was different from that of the Mechanical Index, which indicates a need for a specific dosimetric parameter for safety guidance in pulmonary ultrasound. PMID:25746909

  9. Munchausen Syndrome by Proxy: Medical Diagnostic Criteria.

    ERIC Educational Resources Information Center

    Rosenberg, Donna Andrea

    2003-01-01

    Medical diagnostic criteria for Munchausen Syndrome by Proxy (a persistent fabrication by one individual of illness in another) are presented. Since the strength of the known facts may vary from case to case, diagnostic criteria are given for a definitive diagnosis, a possible diagnosis, an inconclusive determination, and the definitely excluded…

  10. Watermarking of ultrasound medical images in teleradiology using compressed watermark.

    PubMed

    Badshah, Gran; Liew, Siau-Chuin; Zain, Jasni Mohamad; Ali, Mushtaq

    2016-01-01

    The open accessibility of Internet-based medical images in teleradialogy face security threats due to the nonsecured communication media. This paper discusses the spatial domain watermarking of ultrasound medical images for content authentication, tamper detection, and lossless recovery. For this purpose, the image is divided into two main parts, the region of interest (ROI) and region of noninterest (RONI). The defined ROI and its hash value are combined as watermark, lossless compressed, and embedded into the RONI part of images at pixel's least significant bits (LSBs). The watermark lossless compression and embedding at pixel's LSBs preserve image diagnostic and perceptual qualities. Different lossless compression techniques including Lempel-Ziv-Welch (LZW) were tested for watermark compression. The performances of these techniques were compared based on more bit reduction and compression ratio. LZW was found better than others and used in tamper detection and recovery watermarking of medical images (TDARWMI) scheme development to be used for ROI authentication, tamper detection, localization, and lossless recovery. TDARWMI performance was compared and found to be better than other watermarking schemes. PMID:26839914

  11. Prehospital stroke diagnostics based on neurological examination and transcranial ultrasound

    PubMed Central

    2014-01-01

    Background Transcranial color-coded sonography (TCCS) has proved to be a fast and reliable tool for the detection of middle cerebral artery (MCA) occlusions in a hospital setting. In this feasibility study on prehospital sonography, our aim was to investigate the accuracy of TCCS for neurovascular emergency diagnostics when performed in a prehospital setting using mobile ultrasound equipment as part of a neurological examination. Methods Following a ‘911 stroke code’ call, stroke neurologists experienced in TCCS rendezvoused with the paramedic team. In patients with suspected stroke, TCCS examination including ultrasound contrast agents was performed. Results were compared with neurovascular imaging (CTA, MRA) and the final discharge diagnosis from standard patient-centered stroke care. Results We enrolled ‘232 stroke code’ patients with follow-up data available in 102 patients with complete TCCS examination. A diagnosis of ischemic stroke was made in 73 cases; 29 patients were identified as ‘stroke mimics’. MCA occlusion was diagnosed in ten patients, while internal carotid artery (ICA) occlusion/high-grade stenosis leading to reversal of anterior cerebral artery flow was diagnosed in four patients. The initial working diagnosis ‘any stroke’ showed a sensitivity of 94% and a specificity of 48%. ‘Major MCA or ICA stroke’ diagnosed by mobile ultrasound showed an overall sensitivity of 78% and specificity of 98%. Conclusions The study demonstrates the feasibility and high diagnostic accuracy of emergency transcranial ultrasound assessment combined with neurological examinations for major ischemic stroke. Future combination with telemedical support, point-of-care analysis of blood serum markers, and probability algorithms of prehospital stroke diagnosis including ultrasound may help to speed up stroke treatment. PMID:24572006

  12. Bedside ultrasound education in Canadian medical schools: A national survey

    PubMed Central

    Steinmetz, Peter; Dobrescu, Octavian; Oleskevich, Sharon; Lewis, John

    2016-01-01

    Background This study was carried out to determine the extent and characteristics of bedside ultrasound teaching in medical schools across Canada. Methods A cross-sectional, survey-based study was used to assess undergraduate bedside ultrasound education in the 17 accredited medical schools in Canada. The survey, consisting of 19 questions was pilot-tested, web-based, and completed over a period of seven months in 2014. Results Approximately half of the 13 responding medical schools had integrated bedside ultrasound teaching into their undergraduate curriculum. The most common trends in undergraduate ultrasound teaching related to duration (1–5 hours/year in 50% of schools), format (practical and theoretical in 67% of schools), and logistics (1:4 instructor to student ratio in 67% of schools). The majority of responding vice-deans indicated that bedside ultrasound education should be integrated into the medical school curriculum (77%), and cited a lack of ultrasound machines and infrastructure as barriers to integration. Conclusions This study documents the current characteristics of undergraduate ultrasound education in Canada. PMID:27103956

  13. How 3D immersive visualization is changing medical diagnostics

    NASA Astrophysics Data System (ADS)

    Koning, Anton H. J.

    2011-03-01

    Originally the only way to look inside the human body without opening it up was by means of two dimensional (2D) images obtained using X-ray equipment. The fact that human anatomy is inherently three dimensional leads to ambiguities in interpretation and problems of occlusion. Three dimensional (3D) imaging modalities such as CT, MRI and 3D ultrasound remove these drawbacks and are now part of routine medical care. While most hospitals 'have gone digital', meaning that the images are no longer printed on film, they are still being viewed on 2D screens. However, this way valuable depth information is lost, and some interactions become unnecessarily complex or even unfeasible. Using a virtual reality (VR) system to present volumetric data means that depth information is presented to the viewer and 3D interaction is made possible. At the Erasmus MC we have developed V-Scope, an immersive volume visualization system for visualizing a variety of (bio-)medical volumetric datasets, ranging from 3D ultrasound, via CT and MRI, to confocal microscopy, OPT and 3D electron-microscopy data. In this talk we will address the advantages of such a system for both medical diagnostics as well as for (bio)medical research.

  14. Asynchronous compressed beamformer for portable diagnostic ultrasound systems.

    PubMed

    Zhou, Jun; Hoyos, Sebastian; Sadler, Brian

    2014-11-01

    State-of-the-art portable ultrasound imaging systems employ a small transducer array and a low carrier frequency to fit stringent constraints on power and form factor, and this tends to compromise the ultrasound imaging quality. In this paper, we present a low-complexity low-power asynchronous compressed beamformer (ACB) for portable diagnostic ultrasound. The proposed ACB integrates asynchronous sampling and compressive sensing (CS), and is capable of reducing data conversion power and handling a large data volume at the mixed-signal interface. A high-rate continuoustime ternary encoding (CT-TE) scheme eliminates the need for interpolation filters and coordinate rotation digital computer (CORDIC) units typically used in a conventional architecture. A split-projection least squares (SPLS) signal reconstruction algorithm is applied that replaces high-cost nonlinear signal recovery with a series of low-complexity and independent linear problems. Experiments with measured ultrasound data demonstrate the proposed ACB architecture, and the SPLS reconstruction algorithm achieves 9-fold data compression compared with Nyquist sampling. PMID:25389158

  15. Application of tele-ultrasound in emergency medical services.

    PubMed

    Su, Mei-Ju; Ma, Huei-Ming; Ko, Chow-In; Chiang, Wen-Chu; Yang, Chih-Wei; Chen, Sao-Jie; Chen, Robert; Chen, Heng-Shuen

    2008-10-01

    In emergency medical services, portable ultrasound scanners have the potential to become new-age stethoscopes for emergency physicians. For trauma cases in particular, portable ultrasound scanners can scan the chest and abdomen of emergency patients both rapidly and conveniently. This study describes the development of tele-ultrasound for pre-diagnosis in a medical emergency setting as a part of the updated Mobile Hospital Emergency Medical System (MHEMS). An emergency medical technician can provide an emergency physician with a patient's ultrasound images and medical information during the patient's pre-hospitalization and transportation period using a combination of the MHEMS, the portable ultrasound scanner, and the onboard 3G communication capabilities. The MHEMS includes a Dispatch and Mission Control Center that facilitates the communication between the Emergency Department of a specified hospital, the systems aboard the ambulance. Early receipt of information relevant to the patient will enhance pre-diagnosis options for on-duty emergency physicians and allow for a hospital's emergency department to promptly prepare necessary surgical instruments or beds. Furthermore, emergency medical technicians can also obtain instructions from on-duty physicians to enhance damage and disaster control ability in critical moments. PMID:18954253

  16. A recommender system for medical imaging diagnostic.

    PubMed

    Monteiro, Eriksson; Valente, Frederico; Costa, Carlos; Oliveira, José Luís

    2015-01-01

    The large volume of data captured daily in healthcare institutions is opening new and great perspectives about the best ways to use it towards improving clinical practice. In this paper we present a context-based recommender system to support medical imaging diagnostic. The system relies on data mining and context-based retrieval techniques to automatically lookup for relevant information that may help physicians in the diagnostic decision. PMID:25991188

  17. Diagnostic accuracy of postnatal ultrasound screening for urinary tract abnormalities.

    PubMed

    Hálek, Jan; Flögelová, Hana; Michálková, Kamila; Smakal, Oldrich; Dubrava, Lubomír; Zapletalová, Jana; Janout, Vladimír

    2010-02-01

    The study was aimed at (1) the determination of the incidence of abnormalities of the urinary tract in newborn infants detected by postnatal ultrasound screening, and (2) the evaluation of the diagnostic accuracy of postnatal ultrasound screening for detecting surgical urinary tract abnormalities. The prospective study was of full-term neonates born in the University Hospital of Olomouc in 2005-2008 who underwent renal ultrasound screening after 72 h of life. Significant findings were recorded. Subsequent diagnostic and therapeutic procedures were recorded and evaluated in a group of children with detected renal pelvic dilatation (RPD). (1) A total of 6,088 newborn infants was examined. The absolute and relative RPD incidence rates (anteroposterior diameter, APD) were as follows: 5-7 mm, 146 (2.4%); 7-10 mm, 70 (1.15%); 10-15 mm, 13 (0.21%), and 15 mm or more, 5 (0.08%). Of those, 16 children were operated on for abnormalities of the urinary tract, of which nine (56%) had been detected by prenatal screening. Other findings: six cases of unilateral renal agenesis, four cases of multicystic renal dysplasia, four of renal dystopia, one of polycystic kidney disease and one of renal hypoplasia. (2) A group of 224 children with postnatally detected RPD was examined, of whom 40 (17.9%) underwent voiding cystourethrography and/or scintigraphy and 16 (7.1%) were treated surgically. The receiver operating characteristic curves were analyzed, and the areas under the curves were calculated. Postnatal renal ultrasound screening is probably a suitable test for detecting significant urinary tract abnormalities. PMID:19856001

  18. Intelligent medical diagnostics via molecular logic

    PubMed Central

    Konry, Tania; Walt, David R.

    2009-01-01

    In this communication, we describe the integration of microarray sensor technology with logic capability for screening combinations of proteins and DNA in a biological sample. In this system, we have demonstrated the use of a single platform amenable to both protein detection and protein-DNA detection using molecular logic gates. The pattern of protein and DNA inputs results in fluorescence outputs according to a truth table for AND and INHIBIT gates, thereby demonstrating the feasibility of performing medical diagnostics using a logic gate design. One possible application of this technique would be for the direct screening of various medical conditions that are dependent on combinations of diagnostic markers. PMID:19715272

  19. An introduction to the use of diagnostic ultrasound.

    PubMed

    Sweet, E M; Arneil, G C

    1975-10-01

    This article is meant to serve as a simple introduction to diagnostic ultrasound, explaining the nature of sonar and the basic equipment for its production and use. A scans, B scans, time-position scans, and Doppler-shift techniques are described, with some examples of the clinical applications of each. Some recent innovations such as scan conversion to improve gray scaling and electrocardiographically triggered cardiac sector scans are mentioned. The limitations of the technique are indicated, with measures that can be adopted to reduce them. The safety of the procedure is emphasized, with its freedom from the known biological effects of ionizing radiation. PMID:1209271

  20. Photoacoustic sensor for medical diagnostics

    NASA Astrophysics Data System (ADS)

    Wolff, Marcus; Groninga, Hinrich G.; Harde, Hermann

    2004-03-01

    The development of new optical sensor technologies has a major impact on the progress of diagnostic methods. Of the permanently increasing number of non-invasive breath tests, the 13C-Urea Breath Test (UBT) for the detection of Helicobacter pylori is the most prominent. However, many recent developments, like the detection of cancer by breath test, go beyond gastroenterological applications. We present a new detection scheme for breath analysis that employs an especially compact and simple set-up. Photoacoustic Spectroscopy (PAS) represents an offset-free technique that allows for short absorption paths and small sample cells. Using a single-frequency diode laser and taking advantage of acoustical resonances of the sample cell, we performed extremely sensitive and selective measurements. The smart data processing method contributes to the extraordinary sensitivity and selectivity as well. Also, the reasonable acquisition cost and low operational cost make this detection scheme attractive for many biomedical applications. The experimental set-up and data processing method, together with exemplary isotope-selective measurements on carbon dioxide, are presented.

  1. American Medical Society for Sports Medicine recommended sports ultrasound curriculum for sports medicine fellowships.

    PubMed

    Finnoff, Jonathan T; Berkoff, David; Brennan, Fred; DiFiori, John; Hall, Mederic M; Harmon, Kimberly; Lavallee, Mark; Martin, Sean; Smith, Jay; Stovak, Mark

    2015-01-01

    The following sports ultrasound (SPORTS US) curriculum is a revision of the curriculum developed by the American Medical Society for Sports Medicine (AMSSM) in 2010. Several changes have been made to the curriculum with the primary aim of providing a pathway by which a sports medicine fellow can obtain sufficient SPORTS US training to become proficient in the core competencies of SPORTS US. The core competencies of SPORTS US are outlined in the learning objectives section of this document. The term "SPORTS US" was purposefully chosen rather than "musculoskeletal ultrasound" (MSK US) because it was recognized by the panel that the evolving field of SPORTS US encompasses non-MSK applications of ultrasound such as the FAST examination (focused assessment with sonography for trauma). Although the SPORTS US core competencies in this curriculum are all MSK in nature, they represent the minimum SPORTS US knowledge a sports medicine fellow should acquire during fellowship. However, additional training in more advanced MSK and non-MSK applications of ultrasound can be provided at the fellowship director's discretion. Completion of this SPORTS US curriculum fulfills the American Institute of Ultrasound in Medicine's (AIUM) requirements to perform an MSK US examination and the prerequisites for the American Registry for Diagnostic Medical Sonography's (ARDMS) MSK sonography certification examination. PMID:25536482

  2. [Clinical trial requests of indigenous diagnostic imaging ultrasound devices in first-time registration application].

    PubMed

    Guo, Zhaojun; Cao, Guofang; Tao, Kan

    2012-11-01

    This article introduces the clinical requests of indigenous diagnostic imaging ultrasound devices in first-time registration application and the clinical trial requests in Technical Review Guidance of Ultrasound Imaging Diagnostic Devices (category III) Registration and puts forward some questions of the guidance's implementation. It is hoped to help concerned people. PMID:23461122

  3. Performance of Bedside Diagnostic Ultrasound in an Ebola Isolation Unit: The Emory University Hospital Experience

    PubMed Central

    Moreno, Courtney C.; Kraft, Colleen S.; Vanairsdale, Sharon; Kandiah, Prem; Klopman, Matthew A.; Ribner, Bruce S.; Tridandapani, Srini

    2015-01-01

    OBJECTIVE Individuals with Ebola virus disease, a contagious and potentially lethal infection, are now being treated in specialized units in the United States. We describe Emory University's initial experience, current operating procedures, and ongoing planning with diagnostic ultrasound in the isolation unit. CONCLUSION Ultrasound use has been limited to date. Future planning considerations include deciding what types of ultrasound studies will be performed, which personnel will acquire the images, and which ultrasound machine will be used. PMID:25730332

  4. Compressive Deconvolution in Medical Ultrasound Imaging.

    PubMed

    Chen, Zhouye; Basarab, Adrian; Kouame, Denis

    2016-03-01

    The interest of compressive sampling in ultrasound imaging has been recently extensively evaluated by several research teams. Following the different application setups, it has been shown that the RF data may be reconstructed from a small number of measurements and/or using a reduced number of ultrasound pulse emissions. Nevertheless, RF image spatial resolution, contrast and signal to noise ratio are affected by the limited bandwidth of the imaging transducer and the physical phenomenon related to US wave propagation. To overcome these limitations, several deconvolution-based image processing techniques have been proposed to enhance the ultrasound images. In this paper, we propose a novel framework, named compressive deconvolution, that reconstructs enhanced RF images from compressed measurements. Exploiting an unified formulation of the direct acquisition model, combining random projections and 2D convolution with a spatially invariant point spread function, the benefit of our approach is the joint data volume reduction and image quality improvement. The proposed optimization method, based on the Alternating Direction Method of Multipliers, is evaluated on both simulated and in vivo data. PMID:26513780

  5. Boosting medical diagnostics by pooling independent judgments

    PubMed Central

    Kurvers, Ralf H. J. M.; Herzog, Stefan M.; Hertwig, Ralph; Krause, Jens; Carney, Patricia A.; Bogart, Andy; Argenziano, Giuseppe; Zalaudek, Iris; Wolf, Max

    2016-01-01

    Collective intelligence refers to the ability of groups to outperform individual decision makers when solving complex cognitive problems. Despite its potential to revolutionize decision making in a wide range of domains, including medical, economic, and political decision making, at present, little is known about the conditions underlying collective intelligence in real-world contexts. We here focus on two key areas of medical diagnostics, breast and skin cancer detection. Using a simulation study that draws on large real-world datasets, involving more than 140 doctors making more than 20,000 diagnoses, we investigate when combining the independent judgments of multiple doctors outperforms the best doctor in a group. We find that similarity in diagnostic accuracy is a key condition for collective intelligence: Aggregating the independent judgments of doctors outperforms the best doctor in a group whenever the diagnostic accuracy of doctors is relatively similar, but not when doctors’ diagnostic accuracy differs too much. This intriguingly simple result is highly robust and holds across different group sizes, performance levels of the best doctor, and collective intelligence rules. The enabling role of similarity, in turn, is explained by its systematic effects on the number of correct and incorrect decisions of the best doctor that are overruled by the collective. By identifying a key factor underlying collective intelligence in two important real-world contexts, our findings pave the way for innovative and more effective approaches to complex real-world decision making, and to the scientific analyses of those approaches. PMID:27432950

  6. Boosting medical diagnostics by pooling independent judgments.

    PubMed

    Kurvers, Ralf H J M; Herzog, Stefan M; Hertwig, Ralph; Krause, Jens; Carney, Patricia A; Bogart, Andy; Argenziano, Giuseppe; Zalaudek, Iris; Wolf, Max

    2016-08-01

    Collective intelligence refers to the ability of groups to outperform individual decision makers when solving complex cognitive problems. Despite its potential to revolutionize decision making in a wide range of domains, including medical, economic, and political decision making, at present, little is known about the conditions underlying collective intelligence in real-world contexts. We here focus on two key areas of medical diagnostics, breast and skin cancer detection. Using a simulation study that draws on large real-world datasets, involving more than 140 doctors making more than 20,000 diagnoses, we investigate when combining the independent judgments of multiple doctors outperforms the best doctor in a group. We find that similarity in diagnostic accuracy is a key condition for collective intelligence: Aggregating the independent judgments of doctors outperforms the best doctor in a group whenever the diagnostic accuracy of doctors is relatively similar, but not when doctors' diagnostic accuracy differs too much. This intriguingly simple result is highly robust and holds across different group sizes, performance levels of the best doctor, and collective intelligence rules. The enabling role of similarity, in turn, is explained by its systematic effects on the number of correct and incorrect decisions of the best doctor that are overruled by the collective. By identifying a key factor underlying collective intelligence in two important real-world contexts, our findings pave the way for innovative and more effective approaches to complex real-world decision making, and to the scientific analyses of those approaches. PMID:27432950

  7. Robert Apfel's contribution to clinical diagnostic ultrasound: The mechanical index

    NASA Astrophysics Data System (ADS)

    Holland, Christy K.

    2001-05-01

    The mechanical index, MI, resulted from theoretical considerations of the short-pulse acoustic threshold for inertial cavitation in water populated with microbubbles of all sizes [R. E. Apfel and C. K. Holland, Ultrasound Med Biol. 17, 179-185 (1991)]. In this review, the onset of cavitation will be discussed with reference to Robert Apfel's legacy of theoretical and experimental data. The questions arise: Can the utility of the MI be extended to situations in which the threshold MI is exceeded, thereby allowing for some estimate of the quantification of a potential bioeffect due to microcavitation? Also, can the MI be extended to situations in which pulses are, unlike the original formulation, not short? Is there a theoretical or semi-empirical basis for the MI threshold below which cavitation is unlikely? Can the MI be used to predict gas contrast agent destruction? The possible consequences of gas body activation associated with aerated lung tissue, intestinal gas pockets or encapsulated gas contrast agents represent specific instances of cavitation considerations relevant to clinical practice. Monitoring the real-time display of the MI (mandated by the FDA) helps clinicians evaluate and minimize the potential risks in the use of diagnostic ultrasound instrumentation. [Research supported by National Institutes of Health Grant R29 HL58761.

  8. Ultrasound in Space Medicine

    NASA Technical Reports Server (NTRS)

    Dulchavsky, Scott A.; Sargsyan, A.E.

    2009-01-01

    This slide presentation reviews the use of ultrasound as a diagnostic tool in microgravity environments. The goals of research in ultrasound usage in space environments are: (1) Determine accuracy of ultrasound in novel clinical conditions. (2) Determine optimal training methodologies, (3) Determine microgravity associated changes and (4) Develop intuitive ultrasound catalog to enhance autonomous medical care. Also uses of Ultrasound technology in terrestrial applications are reviewed.

  9. Diagnostic Usefulness of Transrectal Ultrasound Compared with Transvaginal Ultrasound Assessment in Young Korean Women with Polycystic Ovary Syndrome

    PubMed Central

    Lee, Da Eun; Park, So Yun; Lee, Sa Ra; Chung, Hye Won

    2015-01-01

    Objectives To determine the diagnostic performance of transrectal ultrasound in virgin patients with polycystic ovary syndrome (PCOS) by receiver operating characteristic (ROC) curve analysis, compared with conventional transvaginal ultrasound assessment. Methods Ultrasound examinations were performed in 963 Korean women, with transvaginal transducers in 677 women and transrectal transducers in 286 women at Ewha Womans University Mokdong Hospital. Transvaginal ultrasound examinations were performed in 494 normal control women and 183 PCOS patients according to National Institutes of Health (NIH) PCOS diagnostic criteria. In virgin patients, transrectal ultrasound examinations were performed in 141 normal control women and 145 PCOS patients. ROC curves were calculated for ovarian volume and follicle number. Results By transvaginal ultrasound examination, the ovarian volume showed an area under the ROC curve (AURC) of 0.838. An ovarian volume decision threshold > 7 cm3 had a sensitivity of 73.0% and a specificity of 84.2% for the diagnosis of PCOS. The follicle number showed an AURC of 0.886. A follicle number decision threshold ≥ 9 had a sensitivity of 78.6% and a specificity of 87.2% for the diagnosis of PCOS. By transrectal ultrasound examination, the ovarian volume and the follicle number showed AURCs of 0.815 as same thresholds with a sensitivity of 67.2% and 66.4%, respectively and a specificity of 86.8% each. Ovarian volume and follicle number by transvaginal and transrectal ultrasound assessment had a high diagnostic power for PCOS screening. Conclusion Transrectal ultrasound assessment is as effective as conventional transvaginal ultrasound for the detection of PCOS in virgin patients. PMID:26793680

  10. 78 FR 1166 - Medical Diagnostic Equipment Accessibility Standards Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-08

    ... Medical Diagnostic Equipment Accessibility Standards. See 77 FR 6916 (February 9, 2012). The NPRM and... TRANSPORTATION BARRIERS COMPLIANCE BOARD 36 CFR Part 1195 RIN 3014-AA40 Medical Diagnostic Equipment.... ACTION: Notice of advisory committee meeting. SUMMARY: The Medical Diagnostic Equipment...

  11. Proposed standard thermal test object for medical ultrasound.

    PubMed

    Shaw, A; Pay, N M; Preston, R C; Bond, A D

    1999-01-01

    A general design for a thermal test object (TTO) is proposed. A number of novel features make the design particularly suitable for use as a standardised device for assessing the heating capability of diagnostic ultrasound beams. To assess performance, soft-tissue TTOs have been made containing thin-film thermocouples sandwiched between discs of tissue-mimicking gel. Installed in an appropriate measurement system, these TTOs exhibit excellent thermal and spatial resolution, allowing the ultrasound beam to be located rapidly and reproducibly. The measured temperature rise after 3 minutes of heating has been compared with theoretical predictions based on measured pressure distributions, and agreement is within 10%. Other studies have shown that soft-tissue- and bone-mimicking TTOs can be used to evaluate a wide range of ultrasound fields and that different physical tissue models can be simulated. It is concluded that this design would be suitable for providing reference assessments of the thermal hazard posed by diagnostic ultrasound under standardised conditions. PMID:10048809

  12. Acoustic Waves in Medical Imaging and Diagnostics

    PubMed Central

    Sarvazyan, Armen P.; Urban, Matthew W.; Greenleaf, James F.

    2013-01-01

    Up until about two decades ago acoustic imaging and ultrasound imaging were synonymous. The term “ultrasonography,” or its abbreviated version “sonography” meant an imaging modality based on the use of ultrasonic compressional bulk waves. Since the 1990s numerous acoustic imaging modalities started to emerge based on the use of a different mode of acoustic wave: shear waves. It was demonstrated that imaging with these waves can provide very useful and very different information about the biological tissue being examined. We will discuss physical basis for the differences between these two basic modes of acoustic waves used in medical imaging and analyze the advantages associated with shear acoustic imaging. A comprehensive analysis of the range of acoustic wavelengths, velocities, and frequencies that have been used in different imaging applications will be presented. We will discuss the potential for future shear wave imaging applications. PMID:23643056

  13. A fully programmable computing architecture for medical ultrasound machines.

    PubMed

    Schneider, Fabio Kurt; Agarwal, Anup; Yoo, Yang Mo; Fukuoka, Tetsuya; Kim, Yongmin

    2010-03-01

    Application-specific ICs have been traditionally used to support the high computational and data rate requirements in medical ultrasound systems, particularly in receive beamforming. Utilizing the previously developed efficient front-end algorithms, in this paper, we present a simple programmable computing architecture, consisting of a field-programmable gate array (FPGA) and a digital signal processor (DSP), to support core ultrasound signal processing. It was found that 97.3% and 51.8% of the FPGA and DSP resources are, respectively, needed to support all the front-end and back-end processing for B-mode imaging with 64 channels and 120 scanlines per frame at 30 frames/s. These results indicate that this programmable architecture can meet the requirements of low- and medium-level ultrasound machines while providing a flexible platform for supporting the development and deployment of new algorithms and emerging clinical applications. PMID:19546045

  14. Ultrasound-based lectures on cardiovascular physiology and reflexes for medical students.

    PubMed

    Paganini, M; Rubini, A

    2016-06-01

    Ultrasound has become a widely used diagnostic technique. While its role in patient evaluation is well known, its utility during preclinical courses such as anatomy and physiology is becoming increasingly recognized. The aim of the present study was to assess the feasibility/utility of integrating ultrasound-based sessions into conventional undergraduate medical school programs of physiology of the cardiovascular system and cardiovascular reflexes and to evaluate student perceptions of an ultrasound-based didactic session. Second-year medical students enrolled in the University of Padova attended a didactic session during which basic concepts regarding ultrasound instrumentation, image production, and spatial orientation were presented. Five anatomic sectors (the heart, aorta, neck vessels, inferior vena cava, and femoral veins) were then examined on a volunteer. Student perceptions of the images that were projected, the usefulness of the presentation, and the reproducibility of the experience were assessed at the end of the lecture with an anonymous questionnaire consisting of positive and negative items that were rated using a 5-point Likert scale and with two questions. One hundred eleven students attended the lecture; 99% of them found it very interesting, and none considered it boring or a waste of time. More than 96% thought it helped them to gain a better comprehension of the subject and would recommend it to a colleague. In conclusion, as ultrasound has been found to be a valuable resource for the teaching of physiology of the cardiovascular system and cardiovascular reflexes, efforts should be made to integrate ultrasound sessions into the traditional human physiology curriculum. PMID:27161816

  15. The feasibility of non-contact ultrasound for medical imaging

    NASA Astrophysics Data System (ADS)

    Clement, G. T.; Nomura, H.; Adachi, H.; Kamakura, T.

    2013-09-01

    High intensity focused ultrasound in air may provide a means for medical and biological imaging without direct coupling of an ultrasound probe. In this study, an approach based on highly focused ultrasound in air is described and the feasibility of the technique is assessed. The overall method is based on the observations that (1) ultrasound in air has superior focusing ability and stronger nonlinear harmonic generation as compared to tissue propagation and (2) a tightly focused field directed into tissue causes point-like spreading that may be regarded as a source for generalized diffraction tomography. Simulations of a spherically-curved transducer are performed, where the transducer's radiation pattern is directed from air into tissue. It is predicted that a focal pressure of 162 dB (2.5 kPa) is sufficient to direct ultrasound through the body, and provide a small but measurable signal (∼1 mPa) upon exit. Based on the simulations, a 20 cm diameter array consisting of 298 transducers is constructed. For this feasibility study, a 40 kHz resonance frequency is selected based on the commercial availability of such transducers. The array is used to focus through water and acrylic phantoms, and the time history of the exiting signal is evaluated. Sufficient data are acquired to demonstrate a low-resolution tomographic reconstruction. Finally, to demonstrate the feasibility to record a signal in vivo, a 75 mm × 55 mm section of a human hand is imaged in a C-mode configuration.

  16. Educational Assessment of Medical Student Rotation in Emergency Ultrasound

    PubMed Central

    Fox, J. Christian; Cusick, Seric; Scruggs, William; Henson, Travis W.; Anderson, Craig L; Barajas, Graciela; Zlidenny, Alexander; McDonough, JoAnne; Langdorf, Mark I.

    2007-01-01

    Background Medical student ultrasound education is sparse. In 2002, we began the first medical student rotation in emergency ultrasound. Objective To evaluate if medical students can learn and retain sonographic skills during a two- or four-week elective. Methods We gave students an exam on the first and last days of the rotation. Six months later, students took the exam a third time. A control group was used for comparison. Results Over a 19-month period, we enrolled 45 students (25 on the two-week and 20 on the four-week elective). The four-week student post-test score was significantly better than the two- week post-test score (81% vs 72%, p=0.003). On the six-month exam, the four-week student post-test score was significantly better than the two-week post-test score (77% vs 69%, p=0.008). The control group did not statistically improve. Conclusion Medical students can learn bedside ultrasound interpretation with clinical integration and retain the knowledge six months later. PMID:19561689

  17. Noninvasive Characterization of In situ Forming Implants Using Diagnostic Ultrasound

    PubMed Central

    Solorio, Luis; Babin, Brett M.; Patel, Ravi B.; Mach, Justyna; Azar, Nami

    2010-01-01

    In situ forming drug delivery systems provide a means by which a controlled release depot can be physically inserted into a target site without the use of surgery. The release rate of drugs from these systems is often related to the rate of implant formation. Currently, only a limited number of techniques are available to monitor phase inversion, and none of these methods can be used to visualize the process directly and noninvasively. In this study, diagnostic ultrasound was used to visualize and quantify the process of implant formation in a phase inversion based system both in vitro and in vivo. Concurrently, sodium fluorescein was used as a mock drug to evaluate the drug release profiles and correlate drug release and implant formation processes. Implants comprised of three different molecular weight poly(lactic-co-glycolic acid) (PLGA) polymers dissolved in 1-methyl-2-pyrrolidinone (NMP) were studied in vitro and a 29 kDa PLGA solution was evaluated in vivo. The implants were encapsulated in a 1% agarose tissue phantom for five days, or injected into a rat subcutaneously and evaluated for 48 hrs. Quantitative measurements of the gray-scale value (corresponding to the rate of implant formation), swelling, and precipitation were evaluated using image analysis techniques, showing that polymer molecular weight has a considerable effect on the swelling and formation of the in situ drug delivery depots. A linear correlation was also seen between the in vivo release and depot formation (R2=0.93). This study demonstrates, for the first time, that ultrasound can be used to noninvasively and nondestructively monitor and evaluate the phase inversion process of in situ forming drug delivery implants, and that the formation process can be directly related to the initial phase of drug release dependent on this formation. PMID:20060859

  18. Diagnostic Reasoning across the Medical Education Continuum

    PubMed Central

    Smith, C. Scott; Hill, William; Francovich, Chris; Morris, Magdalena; Robbins, Bruce; Robins, Lynne; Turner, Andrew

    2014-01-01

    We aimed to study linguistic and non-linguistic elements of diagnostic reasoning across the continuum of medical education. We performed semi-structured interviews of premedical students, first year medical students, third year medical students, second year internal medicine residents, and experienced faculty (ten each) as they diagnosed three common causes of dyspnea. A second observer recorded emotional tone. All interviews were digitally recorded and blinded transcripts were created. Propositional analysis and concept mapping were performed. Grounded theory was used to identify salient categories and transcripts were scored with these categories. Transcripts were then unblinded. Systematic differences in propositional structure, number of concept connections, distribution of grounded theory categories, episodic and semantic memories, and emotional tone were identified. Summary concept maps were created and grounded theory concepts were explored for each learning level. We identified three major findings: (1) The “apprentice effect” in novices (high stress and low narrative competence); (2) logistic concept growth in intermediates; and (3) a cognitive state transition (between analytical and intuitive approaches) in experts. These findings warrant further study and comparison.

  19. Wideband Optical Detector of Ultrasound for Medical Imaging Applications

    PubMed Central

    Rosenthal, Amir; Kellnberger, Stephan; Omar, Murad; Razansky, Daniel; Ntziachristos, Vasilis

    2014-01-01

    Optical sensors of ultrasound are a promising alternative to piezoelectric techniques, as has been recently demonstrated in the field of optoacoustic imaging. In medical applications, one of the major limitations of optical sensing technology is its susceptibility to environmental conditions, e.g. changes in pressure and temperature, which may saturate the detection. Additionally, the clinical environment often imposes stringent limits on the size and robustness of the sensor. In this work, the combination of pulse interferometry and fiber-based optical sensing is demonstrated for ultrasound detection. Pulse interferometry enables robust performance of the readout system in the presence of rapid variations in the environmental conditions, whereas the use of all-fiber technology leads to a mechanically flexible sensing element compatible with highly demanding medical applications such as intravascular imaging. In order to achieve a short sensor length, a pi-phase-shifted fiber Bragg grating is used, which acts as a resonator trapping light over an effective length of 350 µm. To enable high bandwidth, the sensor is used for sideway detection of ultrasound, which is highly beneficial in circumferential imaging geometries such as intravascular imaging. An optoacoustic imaging setup is used to determine the response of the sensor for acoustic point sources at different positions. PMID:24895083

  20. The feasibility of non-contact ultrasound for medical imaging.

    PubMed

    Clement, G T; Nomura, H; Adachi, H; Kamakura, T

    2013-09-21

    High intensity focused ultrasound in air may provide a means for medical and biological imaging without direct coupling of an ultrasound probe. In this study, an approach based on highly focused ultrasound in air is described and the feasibility of the technique is assessed. The overall method is based on the observations that (1) ultrasound in air has superior focusing ability and stronger nonlinear harmonic generation as compared to tissue propagation and (2) a tightly focused field directed into tissue causes point-like spreading that may be regarded as a source for generalized diffraction tomography. Simulations of a spherically-curved transducer are performed, where the transducer's radiation pattern is directed from air into tissue. It is predicted that a focal pressure of 162 dB (2.5 kPa) is sufficient to direct ultrasound through the body, and provide a small but measurable signal (∼1 mPa) upon exit. Based on the simulations, a 20 cm diameter array consisting of 298 transducers is constructed. For this feasibility study, a 40 kHz resonance frequency is selected based on the commercial availability of such transducers. The array is used to focus through water and acrylic phantoms, and the time history of the exiting signal is evaluated. Sufficient data are acquired to demonstrate a low-resolution tomographic reconstruction. Finally, to demonstrate the feasibility to record a signal in vivo, a 75 mm × 55 mm section of a human hand is imaged in a C-mode configuration. PMID:23965825

  1. Lung ultrasound in the diagnosis of pneumonia in children: proposal for a new diagnostic algorithm

    PubMed Central

    Capasso, Maria; De Luca, Giuseppe; Prisco, Salvatore; Mancusi, Carlo; Laganà, Bruno; Comune, Vincenzo

    2015-01-01

    Background. Despite guideline recommendations, chest radiography (CR) for the diagnosis of community-acquired pneumonia (CAP) in children is commonly used also in mild and/or uncomplicated cases. The aim of this study is to assess the reliability of lung ultrasonography (LUS) as an alternative test in these cases and suggest a new diagnostic algorithm. Methods. We reviewed the medical records of all patients admitted to the pediatric ward from February 1, 2013 to December 31, 2014 with respiratory signs and symptoms. We selected only cases with mild/uncomplicated clinical course and in which CR and LUS were performed within 24 h of each other. The LUS was not part of the required exams recorded in medical records but performed independently. The discharge diagnosis, made only on the basis of history and physical examination, laboratory and instrumental tests, including CR (without LUS), was used as a reference test to compare CR and LUS findings. Results. Of 52 selected medical records CAP diagnosis was confirmed in 29 (55.7%). CR was positive in 25 cases, whereas LUS detected pneumonia in 28 cases. Four patients with negative CR were positive in ultrasound findings. Instead, one patient with negative LUS was positive in radiographic findings. The LUS sensitivity was 96.5% (95% CI [82.2%–99.9%]), specificity of 95.6% (95% CI [78.0%–99.9%]), positive likelihood ratio of 22.2 (95% CI [3.2–151.2]), and negative likelihood ratio of 0.04 (95% CI [0.01–0.25]) for diagnosing pneumonia. Conclusion. LUS can be considered as a valid alternative diagnostic tool of CAP in children and its use must be promoted as a first approach in accordance with our new diagnostic algorithm. PMID:26587343

  2. [Different educational programs on medical ultrasound examination for radiological technologists and medical technologists].

    PubMed

    Ganjitsuda, Kazunori; Tagawa, Masami; Ikeda, Kenichi; Fukushi, Masahiro; Kameoka, Junichi

    2012-01-01

    Radiological technologists (RTs) and medical technologists (MTs) are legally allowed to work as sonographers performing medical ultrasound examination. Despite the total number, much fewer RTs work as sonographers than MTs. To explore the reason, we investigated educational programs, universities, and colleges for both specialties. First, we established five categories of sonographers' competency: 1) Anatomy for imaging diagnosis, 2) Diseases and diagnosis, 3) Imaging, 4) Structure and principle of the equipment, and 5) Evaluation of image quality, using competence reported by the International Society of Radiographers and Radiological Technologists (ISRRT) and diagnostic competency required of sonographers in Japan. Using these categories, we analyzed the content and total instruction time by lectures and seminars based on information written in the syllabi, and explored the differences in education related to sonographers' competency in both programs. "Anatomy for imaging diagnosis" was taught in 15 RT programs (93.8%), and 6 MT programs (31.6%). "Diseases and diagnosis" was taught in 13 RT programs (86.7%), and 8 MT programs (53.3%). "Imaging" was taught in 14 RT programs (100%), and 13 MT programs (76.5%). "Structure and principle of the equipment" was taught in 12 RT programs (85.7%), and 6 MT programs (31.6%). "Evaluation of image quality" was taught in 11 RT programs (84.6%), and 3 MT programs (15.0%). The average instruction time for RT was longer than for MT programs in all categories. RTs are educated and have a foundation to be sonographers at graduation, and may have the possibility to expand their career in this field. PMID:22975696

  3. Laser optoacoustic tomography for medical diagnostics: principles

    NASA Astrophysics Data System (ADS)

    Oraevsky, Alexander A.; Esenaliev, Rinat O.; Jacques, Steven L.; Tittel, Frank K.

    1996-04-01

    This paper is to describe principles of laser optoacoustic tomography for medical diagnostics. Two types of imaging modes are presented. The first is the tomography in transmission mode, which utilizes detection of stress transients transmitted from the laser-excited volume toward the depth through thick layers of tissue. The second is the tomography in reflection mode which utilizes detection of stress transients generated in superficial tissue layer and reflected back toward tissue surface. To distinguish the two modes, we have abbreviated them as (1) laser optoacoustic tomography in transmission mode, LOATT, and (2) time-resolved stress detection tomography of light absorption, TRSDTLA, in reflection mode where emphasis is made on high spatial resolution of images. The basis for laser optoacoustic tomography is the time-resolved detection of laser-induced transient stress waves, selectively generated in absorbing tissues of diagnostic interest. Such a technique allows one to visualize absorbed light distribution in turbid biological tissues irradiated by short laser pulses. Laser optoacoustic tomography can be used for detection of tissue pathological changes that result in either increased concentration of various tissue chromophores such as hemoglobin or in development of enhanced microcirculation in diseased tissue. Potential areas of applications are diagnosis of cancer, brain hemorrhages, arterial atherosclerotic plaques, and other diseased tissues. In addition, it can provide feedback information during medical treatments. Both LOATT and TRSDTLA utilize laser excitation of biological tissues and sensitive detection of laser-induced stress waves. Optical selectivity is based upon differences in optical properties of pathologically different tissues. Sensitivity comes from stress generation under irradiation conditions of temporal stress confinement. The use of sensitive wide-band lithium niobate acoustic transducers expands limits of laser optoacoustic

  4. Medical Acoustics

    NASA Astrophysics Data System (ADS)

    Beach, Kirk; Dunmire, Barbrina

    Medical acoustics can be subdivided into diagnostics and therapy. Diagnostics are further separated into auditory and ultrasonic methods, and both employ low amplitudes. Therapy (excluding medical advice) uses ultrasound for heating, cooking, permeablizing, activating and fracturing tissues and structures within the body, usually at much higher amplitudes than in diagnostics. Because ultrasound is a wave, linear wave physics are generally applicable, but recently nonlinear effects have become more important, even in low-intensity diagnostic applications.

  5. A Porcine Pneumothorax Model for Teaching Ultrasound Diagnostics

    PubMed Central

    Oveland, Nils Petter; Sloth, Erik; Andersen, Gratien; Lossius, Hans Morten

    2012-01-01

    Objectives: Ultrasound (US) is a sensitive diagnostic tool for detecting pneumothorax (PTX), but methods are needed to optimally teach this technique outside of direct patient care. In training and research settings, porcine PTX models are sometimes used, but the description of the PTX topography in these models is lacking. The study purpose was to define the distribution of air using the reference imaging standard computed tomography (CT), to see if pleural insufflation of air into a live anaesthetized pig truly imitates a PTX in an injured patient. Methods: A unilateral catheter was inserted into one pleural cavity of each of 20 pigs, and 500 mL of air was insufflated. After a complete thoracic CT scan, the anterior, lateral, medial, basal, apical, and posterior components of the PTXs were compared. The amount of air in each location was quantified by measuring the distance from the lung edge to the chest wall (LE-CW). A supine anteroposterior chest radiograph (CXR) was taken from each model and interpreted by a senior radiologist, and the image results were compared to CT. Results: All 20 hemithoraces with PTX were correctly identified by CT, while six remained occult after interpreting the CXRs. The PTXs were anterior (100%), lateral (95%), medial (80%), basal (60%), apical (45%), and posterior (15%). The major proportion of the insufflated 500-mL volume was found in the anterior, medial, and basal recesses. Conclusions: The authors found the distribution of the intrathoracic air to be similar between a porcine model and that to be expected in human trauma patients, all having predominantly anterior PTX topographies. In a training facility, the model is easy to set up and can be scanned by the participants multiple times. To acquire the necessary skills to perform thoracic US examinations for PTX, the porcine models could be useful. PMID:22594363

  6. TOPICAL REVIEW: Capacitive micromachined ultrasonic transducer arrays for minimally invasive medical ultrasound

    NASA Astrophysics Data System (ADS)

    Chen, Jingkuang

    2010-02-01

    This paper reviews the minimally invasive capacitive micromachined ultrasonic transducer (CMUT) arrays for medical diagnosis and therapy. While piezoelectric transducers dominate today's medical ultrasound market, the capacitive micromachined ultrasonic transducer has recently emerged as a promising alternative which delivers a comparable device performance to its piezoelectric counterparts, is compatible with front-end circuit integration, allows high-density imager integration and is relative easy in miniaturization. Utilizing MEMS technology, the substrate of CMUT arrays can be micromachined into miniature platforms with various geometrical shapes, which include needles, three-dimensional prisms, as well as other flexible-substrate configurations. These arrays are useful for reaching deep inside the tissue or an organ with a minimally invasive approach. Due to the close proximity of the transducers to the target organ/tissue, a higher resolution/accuracy of diagnostic information can be achieved. In addition to pulse-echo and photoacoustic imaging, high-power CMUT devices capable of delivering ultrasounds with a pressure greater than 1.0 MPa have been monolithically integrated with imager CMUTs for image-guided therapy (IGT). Such miniature devices would facilitate diagnostic and therapy interventions not possible with conventional piezoelectric transducers.

  7. Ultrasound introscopic image quantitative characteristics for medical diagnosis

    NASA Astrophysics Data System (ADS)

    Novoselets, Mikhail K.; Sarkisov, Sergey S.; Gridko, Alexander N.; Tcheban, Anatoliy K.

    1993-09-01

    The results on computer aided extraction of quantitative characteristics (QC) of ultrasound introscopic images for medical diagnosis are presented. Thyroid gland (TG) images of Chernobil Accident sufferers are considered. It is shown that TG diseases can be associated with some values of selected QCs of random echo distribution in the image. The possibility of these QCs usage for TG diseases recognition in accordance with calculated values is analyzed. The role of speckle noise elimination in the solution of the problem on TG diagnosis is considered too.

  8. [Digital scanning converter for medical endoscopic ultrasound imaging].

    PubMed

    Chen, Xiaodong; Zhang, Hongxu; Zhou, Peifan; Wen, Shijie; Yu, Daoyin

    2009-02-01

    This paper mainly introduces the design of digital scanning converter (DSC) for medical endoscopic ultrasound imaging. Fast modified vector totational CORDIC (FMVR-CORDIC) arithmetic complete coordinate conversion is used to increase the speed of ultrasonic scanning imaging. FPGA is used as the kernel module to control data transferring, related circuits and relevant chips' working, and to accomplish data preprocessing. With the advantages of simple structure, nice flexibility and convenience, it satisfies the demand for real-time displaying in this system. Finally, the original polar coordinate image is transformed to rectangular coordinate grey image through coordinate transformation. The system performances have been validated by the experimental result. PMID:19334546

  9. Expectation-Driven Text Extraction from Medical Ultrasound Images.

    PubMed

    Reul, Christian; Köberle, Philipp; Üçeyler, Nurcan; Puppe, Frank

    2016-01-01

    In this study an expectation-driven approach is proposed to extract data stored as pixel structures in medical ultrasound images. Prior knowledge about certain properties like the position of the text and its background and foreground grayscale values is utilized. Several open source Java libraries are used to pre-process the image and extract the textual information. The results are presented in an Excel table together with the outcome of several consistency checks. After manually correcting potential errors, the outcome is automatically stored in the main database. The proposed system yielded excellent results, reaching an accuracy of 99.94% and reducing the necessary human effort to a minimum. PMID:27577478

  10. Integrated ultrasound and gamma imaging probe for medical diagnosis

    NASA Astrophysics Data System (ADS)

    Pani, R.; Pellegrini, R.; Cinti, M. N.; Polito, C.; Orlandi, C.; Fabbri, A.; De Vincentis, G.

    2016-03-01

    In the last few years, integrated multi-modality systems have been developed, aimed at improving the accuracy of medical diagnosis correlating information from different imaging techniques. In this contest, a novel dual modality probe is proposed, based on an ultrasound detector integrated with a small field of view single photon emission gamma camera. The probe, dedicated to visualize small organs or tissues located at short depths, performs dual modality images and permits to correlate morphological and functional information. The small field of view gamma camera consists of a continuous NaI:Tl scintillation crystal coupled with two multi-anode photomultiplier tubes. Both detectors were characterized in terms of position linearity and spatial resolution performances in order to guarantee the spatial correspondence between the ultrasound and the gamma images. Finally, dual-modality images of custom phantoms are obtained highlighting the good co-registration between ultrasound and gamma images, in terms of geometry and image processing, as a consequence of calibration procedures.

  11. Enhanced cytotoxic effect of cisplatin using diagnostic ultrasound and microbubbles in vitro

    NASA Astrophysics Data System (ADS)

    Sasaki, Noboru; Nakamura, Kensuke; Murakami, Masahiro; Lim, Sue Yee; Ohta, Hiroshi; Yamasaki, Masahiro; Takiguchi, Mitsuyoshi

    2012-10-01

    Diagnostic ultrasound has accomplished drug and gene delivery by ultrasound targeted microbubble destruction (UTMD). However, the efficacy of delivery is still relatively low. Therefore, we optimized conditions of UTMD using diagnostic ultrasound and ultrasound contrast agent microbubbles. Canine thyroid adenocarcinoma cells were cultured in a 96-well plate. After addition of cisplatin and Sonazoid®, the plate was inverted to raise microbubbles near cells and incubated. Cells were exposed to diagnostic ultrasound using a linear probe operated in the contrast harmonic imaging mode. The center frequency was 2.5 MHz with a mechanical index of 1.33 and a frame rate of 48 frames/sec. Cytotoxic effect of cisplatin was evaluated 24h after exposure using trypan blue dye exclusion test. We optimized incubation duration, cisplatin concentration, and the relationship between microbubble concentration and exposure duration. The optimum enhancement was observed at incubation duration of 5min, cisplatin concentration of 1 μg/ml, and microbubble concentration of 2.4 × 105 microbubbles/ml. Exposure duration did not influence the enhancement at the microbubble concentration of 2.4 × 105 microbubbles/ml. Our results suggest that relative low concentrations of drug and microbubbles with short exposure duration might be sufficient for drug delivery by UTMD using diagnostic ultrasound.

  12. 77 FR 14706 - Medical Diagnostic Equipment Accessibility Standards

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-13

    ... the Federal Register, 77 FR 6916, on accessibility standards for medical diagnostic equipment and... published an NPRM in the February 9, 2012 edition of the Federal Register, 77 FR 6916, proposing the... TRANSPORTATION BARRIERS COMPLIANCE BOARD 36 CFR Part 1195 RIN 3014-AA40 Medical Diagnostic...

  13. Medical radiation exposures for diagnostic radiology in Malaysia.

    PubMed

    Ng, K H; Abdullah, B J; Sivalingam, S

    1999-07-01

    The medical radiation usage for diagnostic radiology in Malaysia (a Level II country) for 1990-1994 is reported, enabling a comparison to be made for the first time with the United Nations Scientific Committee on the Effects of Atomic Radiation Report. In 1994, the number of physicians, radiologists, x-ray units, and x-ray examinations per 1,000 population was 0.45, 0.005, 0.065, and 183, respectively. (Level I countries had averages of 2.6, 0.072, 0.35, and 860, respectively). In 1994, a total of 3.6 million x-ray examinations were performed; the annual effective dose per capita to the population was 0.05 mSv, and the collective effective dose was 1,000 person-Sv. Chest examinations contributed 63% of the total. Almost all examinations experienced increasing frequency from 1990 to 1994 except for barium studies, cholecystography, and intravenous urography (-23%, -36%, -51%). These decreases are related to the increasing use of ultrasound and greater availability of fiberoptic endoscopy. Notable increases during the same period were observed in computed tomography (161%), cardiac procedures (190%), and mammography (240%). In order to progress from Level II to Level I status Malaysia needs to expand and upgrade radiological service in tandem with the health care development of the country. PMID:10376539

  14. Use of prehospital ultrasound in North America: a survey of emergency medical services medical directors

    PubMed Central

    2014-01-01

    Background Advances in ultrasound imaging technology have made it more accessible to prehospital providers. Little is known about how ultrasound is being used in the prehospital environment and we suspect that it is not widely used in North America at this time. We believe that EMS system characteristics such as provider training, system size, population served, and type of transport will be associated with use or non-use of ultrasound. Our study objective was to describe the current use of prehospital ultrasound in North America. Methods This study was a cross-sectional survey distributed to EMS directors on the National Association of EMS Physicians (NAEMSP) mailing list. Respondents had the option to complete a paper or electronic survey. Results Of the 755 deliverable surveys we received 255 responses from across Canada and the United states for an overall response rate of 30%. Of respondents, 4.1% of EMS systems (95% CI 1.9, 6.3) reported currently using ultrasound and an additional 21.7% (95% CI 17, 26.4) are considering implementing ultrasound. EMS services using ultrasound have a higher proportion of physicians (p < 0.001) as their highest trained prehospital providers when compared to the survey group as a whole. The most commonly cited current and projected applications are Focused Abdominal Sonography for Trauma (FAST) and assessment of pulseless electrical activity (PEA) arrest. The cost of equipment and training are the most significant barriers to implementation of ultrasound. Most medical directors want evidence that prehospital ultrasound improves patient outcomes prior to implementation. Conclusions Prehospital ultrasound is infrequently used in North America and there are a number of barriers to its implementation, including costs of equipment and training and limited evidence demonstrating improved outcomes. A research agenda for prehospital ultrasound should focus on patient-important outcomes such as morbidity and mortality. Two commonly

  15. VCSEL technology for medical diagnostics and therapeutics

    NASA Astrophysics Data System (ADS)

    Hibbs-Brenner, M. K.; Johnson, K. L.; Bendett, M.

    2009-02-01

    In the 1990's a new laser technology, Vertical Cavity Surface Emitting Lasers, or VCSELs, emerged and transformed the data communication industry. The combination of performance characteristics, reliability and performance/cost ratio allowed high data rate communication to occur over short distances at a commercially viable price. VCSELs have not been widely used outside of this application space, but with the development of new attributes, such as a wider range of available wavelengths, the demonstration of arrays of VCSELs on a single chip, and a variety of package form factors, VCSELs can have a significant impact on medical diagnostic and therapeutic applications. One area of potential application is neurostimulation. Researchers have previously demonstrated the feasibility of using 1850nm light for nerve stimulation. The ability to create an array of VCSELs emitting at this wavelength would allow significantly improved spatial resolution, and multiple parallel channels of stimulation. For instance, 2D arrays of 100 lasers or more can be integrated on a single chip less than 2mm on a side. A second area of interest is non-invasive sensing. Performance attributes such as the narrow spectral width, low power consumption, and packaging flexibility open up new possibilities in non-invasive and/or continuous sensing. This paper will suggest ways in which VCSELs can be implemented within these application areas, and the advantages provided by the unique performance characteristics of the VCSEL. The status of VCSEL technology as a function of available wavelength and array size and form factors will be summarized.

  16. The evolution of an integrated ultrasound curriculum (iUSC) for medical students: 9-year experience.

    PubMed

    Hoppmann, Richard A; Rao, Victor V; Bell, Floyd; Poston, Mary Beth; Howe, Duncan B; Riffle, Shaun; Harris, Stephen; Riley, Ruth; McMahon, Carol; Wilson, L Britt; Blanck, Erika; Richeson, Nancy A; Thomas, Lynn K; Hartman, Celia; Neuffer, Francis H; Keisler, Brian D; Sims, Kerry M; Garber, Matthew D; Shuler, C Osborne; Blaivas, Michael; Chillag, Shawn A; Wagner, Michael; Barron, Keith; Davis, Danielle; Wells, James R; Kenney, Donald J; Hall, Jeffrey W; Bornemann, Paul H; Schrift, David; Hunt, Patrick S; Owens, William B; Smith, R Stephen; Jackson, Allison G; Hagon, Kelsey; Wilson, Steven P; Fowler, Stanley D; Catroppo, James F; Rizvi, Ali A; Powell, Caroline K; Cook, Thomas; Brown, Eric; Navarro, Fernando A; Thornhill, Joshua; Burgis, Judith; Jennings, William R; McCallum, James B; Nottingham, James M; Kreiner, James; Haddad, Robert; Augustine, James R; Pedigo, Norman W; Catalana, Paul V

    2015-12-01

    Interest in ultrasound education in medical schools has increased dramatically in recent years as reflected in a marked increase in publications on the topic and growing attendance at international meetings on ultrasound education. In 2006, the University of South Carolina School of Medicine introduced an integrated ultrasound curriculum (iUSC) across all years of medical school. That curriculum has evolved significantly over the 9 years. A review of the curriculum is presented, including curricular content, methods of delivery of the content, student assessment, and program assessment. Lessons learned in implementing and expanding an integrated ultrasound curriculum are also presented as are thoughts on future directions of undergraduate ultrasound education. Ultrasound has proven to be a valuable active learning tool that can serve as a platform for integrating the medical student curriculum across many disciplines and clinical settings. It is also well-suited for a competency-based model of medical education. Students learn ultrasound well and have embraced it as an important component of their education and future practice of medicine. An international consensus conference on ultrasound education is recommended to help define the essential elements of ultrasound education globally to ensure ultrasound is taught and ultimately practiced to its full potential. Ultrasound has the potential to fundamentally change how we teach and practice medicine to the benefit of learners and patients across the globe. PMID:26589313

  17. Speckle noise reduction of medical ultrasound images in complex wavelet domain using mixture priors.

    PubMed

    Rabbani, Hossein; Vafadust, Mansur; Abolmaesumi, Purang; Gazor, Saeed

    2008-09-01

    Speckle noise is an inherent nature of ultrasound images, which may have negative effect on image interpretation and diagnostic tasks. In this paper, we propose several multiscale nonlinear thresholding methods for ultrasound speckle suppression. The wavelet coefficients of the logarithm of image are modeled as the sum of a noise-free component plus an independent noise. Assuming that the noise-free component has some local mixture distribution (MD), and the noise is either Gaussian or Rayleigh, we derive the minimum mean squared error (MMSE) and the averaged maximum a posteriori (AMAP) estimators for noise reduction. We use Gaussian and Laplacian MD for each noise-free wavelet coefficient to characterize their heavy-tailed property. Since we estimate the parameters of the MD using the expectation maximization (EM) algorithm and local neighbors, the proposed MD incorporates some information about the intrascale dependency of the wavelet coefficients. To evaluate our spatially adaptive despeckling methods, we use both real medical ultrasound and synthetically introduced speckle images for speckle suppression. The simulation results show that our method outperforms several recently and the state-of-the-art techniques qualitatively and quantitatively. PMID:18713684

  18. Acoustic Radiation Force Elasticity Imaging in Diagnostic Ultrasound

    PubMed Central

    Doherty, Joshua R.; Trahey, Gregg E.; Nightingale, Kathryn R.; Palmeri, Mark L.

    2013-01-01

    The development of ultrasound-based elasticity imaging methods has been the focus of intense research activity since the mid-1990s. In characterizing the mechanical properties of soft tissues, these techniques image an entirely new subset of tissue properties that cannot be derived with conventional ultrasound techniques. Clinically, tissue elasticity is known to be associated with pathological condition and with the ability to image these features in vivo, elasticity imaging methods may prove to be invaluable tools for the diagnosis and/or monitoring of disease. This review focuses on ultrasound-based elasticity imaging methods that generate an acoustic radiation force to induce tissue displacements. These methods can be performed non-invasively during routine exams to provide either qualitative or quantitative metrics of tissue elasticity. A brief overview of soft tissue mechanics relevant to elasticity imaging is provided, including a derivation of acoustic radiation force, and an overview of the various acoustic radiation force elasticity imaging methods. PMID:23549529

  19. Objective performance testing and quality assurance of medical ultrasound equipment.

    PubMed

    Thijssen, Johan M; Weijers, Gert; de Korte, Chris L

    2007-03-01

    There is an urgent need for a measurement protocol and software analysis for objective testing of the imaging performance of medical ultrasound equipment from a user's point of view. Methods for testing of imaging performance were developed. Simple test objects were used, which have a long life expectancy. First, the elevational focus (slice thickness) of the transducer was estimated and the in-plane transmit focus was positioned at the same depth. Next, the postprocessing look-up-table (LUT) was measured and linearized. The tests performed were echo level dynamic range (dB), contrast resolution (i.e., gamma of display, number of gray levels/dB) and sensitivity, overall system sensitivity, lateral sensitivity profile, dead zone, spatial resolution and geometric conformity of display. The concept of a computational observer was used to define the lesion signal-to-noise ratio, SNR(L) (or Mahalanobis distance), as a measure for contrast sensitivity. All the measurements were made using digitized images and quantified by objective means, i.e., by image analysis. The whole performance measurement protocol, as well as the quantitative measurements, have been implemented in software. An extensive data-base browser was implemented from which analysis of the images can be started and reports generated. These reports contain all the information about the measurements, such as graphs, images and numbers. The approach of calibrating the gamma by using a linearized LUT was validated by processing simultaneously acquired rf data. The contrast resolution and echo level of the rf data had to be compressed by a factor of two and amplified by a gain factor corresponding to 12 dB. This resulted in contrast curves that were practically identical to those obtained from DICOM image data. The effects of changing the transducer center frequency on the spatial resolution and contrast sensitivity were estimated to illustrate the practical usefulness of the developed approach of quality

  20. Training in Diagnostic Ultrasound: Essentials, Principles, and Standards. Report of a WHO Study Group. Technical Report Series 875.

    ERIC Educational Resources Information Center

    World Health Organization, Geneva (Switzerland).

    This report defines the essential training and skills necessary for the effective employment of diagnostic ultrasound in different health care settings. It reviews the present situation in ultrasonography and the trends in the utilization of diagnostic ultrasound in clinical practice. The report also examines worldwide practice with respect to…

  1. The iterative adaptive approach in medical ultrasound imaging.

    PubMed

    Jensen, Are Charles; Austeng, Andreas

    2014-10-01

    Many medical ultrasound imaging systems are based on sweeping the image plane with a set of narrow beams. Usually, the returning echo from each of these beams is used to form one or a few azimuthal image samples. We model, for each radial distance, jointly the full azimuthal scanline. The model consists of the amplitudes of a set of densely placed potential reflectors (or scatterers), cf. sparse signal representation. To fit the model, we apply the iterative adaptive approach (IAA) on data formed by a sequenced time delay and phase shift. The performance of the IAA in combination with our time-delayed and phase-shifted data are studied on both simulated data of scenes consisting of point targets and hollow cyst-like structures, and recorded ultrasound phantom data from a specially adapted commercially available scanner. The results show that the proposed IAA is more capable of resolving point targets and gives better defined and more geometrically correct cyst-like structures in speckle images compared with the conventional delay-and-sum (DAS) approach. Compared with a Capon beamformer, the IAA showed an improved rendering of cyst-like structures and a similar point-target resolvability. Unlike the Capon beamformer, the IAA has no user parameters and seems unaffected by signal cancellation. The disadvantage of the IAA is a high computational load. PMID:25265177

  2. 3D ultrasound imaging for prosthesis fabrication and diagnostic imaging

    SciTech Connect

    Morimoto, A.K.; Bow, W.J.; Strong, D.S.

    1995-06-01

    The fabrication of a prosthetic socket for a below-the-knee amputee requires knowledge of the underlying bone structure in order to provide pressure relief for sensitive areas and support for load bearing areas. The goal is to enable the residual limb to bear pressure with greater ease and utility. Conventional methods of prosthesis fabrication are based on limited knowledge about the patient`s underlying bone structure. A 3D ultrasound imaging system was developed at Sandia National Laboratories. The imaging system provides information about the location of the bones in the residual limb along with the shape of the skin surface. Computer assisted design (CAD) software can use this data to design prosthetic sockets for amputees. Ultrasound was selected as the imaging modality. A computer model was developed to analyze the effect of the various scanning parameters and to assist in the design of the overall system. The 3D ultrasound imaging system combines off-the-shelf technology for image capturing, custom hardware, and control and image processing software to generate two types of image data -- volumetric and planar. Both volumetric and planar images reveal definition of skin and bone geometry with planar images providing details on muscle fascial planes, muscle/fat interfaces, and blood vessel definition. The 3D ultrasound imaging system was tested on 9 unilateral below-the- knee amputees. Image data was acquired from both the sound limb and the residual limb. The imaging system was operated in both volumetric and planar formats. An x-ray CT (Computed Tomography) scan was performed on each amputee for comparison. Results of the test indicate beneficial use of ultrasound to generate databases for fabrication of prostheses at a lower cost and with better initial fit as compared to manually fabricated prostheses.

  3. Medical ultrasound imager based on time delay spectrometry.

    PubMed

    Heyser, R C; Hestenes, J D; Rooney, J A; Gammell, P M; Le Croissette, D H

    1989-01-01

    A reflection mode proof-of-concept medical ultrasound imager based on time delay spectrometry has been developed and tested. The system uses a broad band swept-frequency signal operating up to 10 MHz. Signal processing using a fast Fourier transform (FFT) permits extraction of range information. The imager has a higher signal-to-noise ratio than pulse-echo systems which allows high resolution at greater depths. The time delay spectrometry (TDS) spread spectrum operates at lower peak intensities than pulse-echo and permits more control of the spectral content and amplitude of the signal. At present, the system is non-real time which degrades in vivo imaging because of averaging over several cardiac cycles and tissue movement. PMID:2643838

  4. Diagnostic image quality in gynaecological ultrasound: Who should measure it, what should we measure and how?

    PubMed Central

    Knapp, Karen

    2013-01-01

    Assessment of diagnostic image quality in gynaecological ultrasound is an important aspect of imaging department quality assurance. This may be addressed through audit, but who should undertake the audit, what should be measured and how, remains contentious. The aim of this study was to identify whether peer audit is a suitable method of assessing the diagnostic quality of gynaecological ultrasound images. Nineteen gynaecological ultrasound studies were independently assessed by six sonographers utilising a pilot version of an audit tool. Outcome measures were levels of inter-rater agreement using different data collection methods (binary scores, Likert scale, continuous scale), effect of ultrasound study difficulty on study score and whether systematic differences were present between reviewers of different clinical grades and length of experience. Inter-rater agreement ranged from moderate to good depending on the data collection method. A continuous scale gave the highest level of inter-rater agreement with an intra-class correlation coefficient of 0.73. A strong correlation (r = 0.89) between study difficulty and study score was yielded. Length of clinical experience between reviewers had no effect on the audit scores, but individuals of a higher clinical grade gave significantly lower scores than those of a lower grade (p = 0.04). Peer audit is a promising tool in the assessment of ultrasound image quality. Continuous scales seem to be the best method of data collection implying a strong element of heuristically driven decision making by reviewing ultrasound practitioners.

  5. Effects of diagnostic ultrasound-targeted microbubble destruction on permeability of normal liver in rats.

    PubMed

    Yang, Dan; Tan, Kai-Bin; Gao, Yun-Hua; Liu, Hong; Yang, Wei-Xiao

    2012-12-01

    This work investigated the effect of diagnostic ultrasound-targeted microbubble destruction (UTMD) on the permeability of normal liver tissue and the safety of this technique. One hundred and four rats were divided into four groups: the control group, the microbubble-only (MB) group, the ultrasound-only (US) group, and the ultrasound-targeted microbubble destruction group (UTMD). The permeabilities of capillaries and cell membranes were determined using Evans blue and lanthanum nitrate as tracers, respectively. The amount of Evans blue was approximately fourfold higher in the UTMD group than in the control, MB-only, and US-only groups (all P<0.01). Evans blue extravasation, visualized as red fluorescence, was detectable by laser confocal scanning microscopy in the parenchyma only in the UTMD group. Lanthanum nitrate-tracing transmission electron microscopy examination indicated that intracellular lanthanum was detectable in the cytoplasm only in the UTMD group. Blood chemical analysis indicated that the effect of diagnostic ultrasound-targeted microbubble destruction on the rats' serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels was transient and recoverable and that this technique had no obvious effect on renal function. Cellular swelling was observed in liver cells in the UTMD group at 0.5 h, but this swelling was no longer apparent after 1 week. These results suggest that diagnostic ultrasound-targeted microbubble destruction can increase the capillary and cell membrane permeabilities in normal liver tissue without a significant increase in hepatic and renal toxicity. PMID:23021237

  6. 77 FR 62479 - Medical Diagnostic Equipment Accessibility Standards Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-15

    ... Medical Diagnostic Equipment Accessibility Standards. See 77 FR 6916 (February 9, 2012). The NPRM and... refrain from using perfume, cologne, and other fragrances for the comfort of other participants (see...

  7. 78 FR 10582 - Medical Diagnostic Equipment Accessibility Standards Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-14

    ... Medical Diagnostic Equipment Accessibility Standards. See 77 FR 6916 (February 9, 2012). The NPRM and... the meetings are requested to refrain from using perfume, cologne, and other fragrances for...

  8. 77 FR 53163 - Medical Diagnostic Equipment Accessibility Standards Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-31

    ...) on Medical Diagnostic Equipment Accessibility Standards. See 77 FR 6916 (February 9, 2012). The NPRM... provided. Persons attending the meetings are requested to refrain from using perfume, cologne, and...

  9. 78 FR 16448 - Medical Diagnostic Equipment Accessibility Standards Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-15

    ... previously published NPRM on Medical Diagnostic Equipment Accessibility Standards. See 77 FR 6916 (February 9... provided. Persons attending the meetings are requested to refrain from using perfume, cologne, and...

  10. Psychomotor skills in medical ultrasound imaging: an analysis of the core skill set.

    PubMed

    Nicholls, Delwyn; Sweet, Linda; Hyett, Jon

    2014-08-01

    Sonographers use psychomotor skills to perform medical ultrasound examinations. Psychomotor skills describe voluntary movements of the limb, joints, and muscles in response to sensory stimuli and are regulated by the motor neural cortex in the brain. We define a psychomotor skill in relation to medical ultrasound imaging as "the unique mental and motor activities required to execute a manual task safely and efficiently for each clinical situation." Skills in clinical ultrasound practice may be open or closed; most skills used in medical ultrasound imaging are open. Open skills are both complex and multidimensional. Visuomotor and visuospatial psychomotor skills are central components of medical ultrasound imaging. Both types of skills rely on learners having a visual exemplar or standard of performance with which to reference their skill performance and evaluate anatomic structures. These are imperative instructional design principles when teaching psychomotor skills. PMID:25063399

  11. Prenatal Sex Selection and Missing Girls in China: Evidence from the Diffusion of Diagnostic Ultrasound

    ERIC Educational Resources Information Center

    Chen, Yuyu; Li, Hongbin; Meng, Lingsheng

    2013-01-01

    How much of the increase in sex ratio (male to female) at birth since the early 1980s in China is attributed to increased prenatal sex selection? This question is addressed by exploiting the differential introduction of diagnostic ultrasound in the country during the 1980s, which significantly reduced the cost of prenatal sex selection. We…

  12. Ultrasound for Distal Forearm Fracture: A Systematic Review and Diagnostic Meta-Analysis

    PubMed Central

    Douma-den Hamer, Djoke; Blanker, Marco H.; Edens, Mireille A.; Buijteweg, Lonneke N.; Boomsma, Martijn F.; van Helden, Sven H.; Mauritz, Gert-Jan

    2016-01-01

    Study Objective To determine the diagnostic accuracy of ultrasound for detecting distal forearm fractures. Methods A systematic review and diagnostic meta-analysis was performed according to the PRISMA statement. We searched MEDLINE, Web of Science and the Cochrane Library from inception to September 2015. All prospective studies of the diagnostic accuracy of ultrasound versus radiography as the reference standard were included. We excluded studies with a retrospective design and those with evidence of verification bias. We assessed the methodological quality of the included studies with the QUADAS-2 tool. We performed a meta-analysis of studies evaluating ultrasound to calculate the pooled sensitivity and specificity with 95% confidence intervals (CI95%) using a bivariate model with random effects. Subgroup and sensitivity analysis were used to examine the effect of methodological differences and other study characteristics. Results Out of 867 publications we included 16 studies with 1,204 patients and 641 fractures. The pooled test characteristics for ultrasound were: sensitivity 97% (CI95% 93–99%), specificity 95% (CI95% 89–98%), positive likelihood ratio (LR) 20.0 (8.5–47.2) and negative LR 0.03 (0.01–0.08). The corresponding pooled diagnostic odds ratio (DOR) was 667 (142–3,133). Apparent differences were shown for method of viewing, with the 6-view method showing higher specificity, positive LR, and DOR, compared to the 4-view method. Conclusion The present meta-analysis showed that ultrasound has a high accuracy for the diagnosis of distal forearm fractures in children when used by proper viewing method. Based on this, ultrasound should be considered a reliable alternative, which has the advantages of being radiation free. PMID:27196439

  13. Handheld Diagnostic Device Delivers Quick Medical Readings

    NASA Technical Reports Server (NTRS)

    2014-01-01

    To monitor astronauts' health remotely, Glenn Research Center awarded SBIR funding to Cambridge, Massachusetts-based DNA Medical Institute, which developed a device capable of analyzing blood cell counts and a variety of medical biomarkers. The technology will prove especially useful in rural areas without easy access to labs.

  14. TEACHING PHYSICS: An experiment to demonstrate the principles and processes involved in medical Doppler ultrasound

    NASA Astrophysics Data System (ADS)

    Andrews, D. G. H.

    2000-09-01

    Doppler ultrasound is widely used in medicine for measuring blood velocity. This paper describes an experiment illustrating the principles of medical Doppler ultrasound. It is designed with A-level/undergraduate physics students in mind. Ultrasound is transmitted in air and reflected from a moving target. The return signal is processed using a series of modules, so that students can discover for themselves how each stage in the instrument works. They can also obtain a quantitative value of the speed of the target.

  15. Sherlock Holmes' methods of deductive reasoning applied to medical diagnostics.

    PubMed

    Miller, L

    1985-03-01

    Having patterned the character of Sherlock Holmes after one of his professors, Sir Arthur Conan Doyle, himself a physician, incorporated many of the didactic qualities of the 19th century medical diagnostician into the character of Holmes. In this paper I explore Holmes's techniques of deductive reasoning and their basis in 19th and 20th century medical diagnostics. PMID:3887762

  16. Sherlock Holmes's Methods of Deductive Reasoning Applied to Medical Diagnostics

    PubMed Central

    Miller, Larry

    1985-01-01

    Having patterned the character of Sherlock Holmes after one of his professors, Sir Arthur Conan Doyle, himself a physician, incorporated many of the didactic qualities of the 19th century medical diagnostician into the character of Holmes. In this paper I explore Holmes's techniques of deductive reasoning and their basis in 19th and 20th century medical diagnostics. PMID:3887762

  17. Errors made in the ultrasound diagnostics of the spleen.

    PubMed

    Walczyk, Joanna; Walas, Maria Krystyna

    2013-03-01

    Ultrasonography, like any imaging method, entails the risk of errors. From among all means of imaging, it is the most subjective and dependent on the examiner's knowledge and experience. This paper presents the causes of examiner-dependent errors as well as those which result from technical settings and preparation of the patient for the examination. Moreover, the authors discuss the most frequent errors in the diagnosis of splenic conditions, which result from insufficient knowledge concerning anatomical variants of this organ, wrong measurements and incorrect examination technique. The mistakes made in the differentiation of focal lesions of the spleen and its hilum are also discussed. Additionally, the differentiation of collateral circulation, lymph nodes and accessory spleens is mentioned. The authors also draw attention to erroneous interpretation of the left liver lobe as a fragment of the spleen as well as the prominent tail of the pancreas filled with gastric contents and intestinal loops as abnormal masses or fluid cisterns in the area of the splenic hilum. Furthermore, the pathologies of the hilum are discussed such as tumors of the splenic flexure of the colon, lesions arising from the left kidney or the left adrenal gland. The authors list characteristic imaging features of the most common focal lesions visualized in a standard ultrasound scan as well as enhancement patterns appearing in contrast-enhanced examinations. The article discusses the features and differentiation of, among others, infarction, splenic cysts including hydatid ones, abscesses and angiomas. The ultrasound appearance of lymphoma and secondary involvement of the spleen by other malignant neoplasms is also mentioned. Moreover, the authors provide useful tips connected with imaging techniques and interpretation of the findings. The ultrasound examination carried out in compliance with current standards allows for an optimal assessment of the organ and reduction of the error

  18. A survey of medical diagnostic imaging technologies

    SciTech Connect

    Heese, V.; Gmuer, N.; Thomlinson, W.

    1991-10-01

    The fields of medical imaging and medical imaging instrumentation are increasingly important. The state-of-the-art continues to advance at a very rapid pace. In fact, various medical imaging modalities are under development at the National Synchrotron Light Source (such as MECT and Transvenous Angiography.) It is important to understand how these techniques compare with today's more conventional imaging modalities. The purpose of this report is to provide some basic information about the various medical imaging technologies currently in use and their potential developments as a basis for this comparison. This report is by no means an in-depth study of the physics and instrumentation of the various imaging modalities; instead, it is an attempt to provide an explanation of the physical bases of these techniques and their principal clinical and research capabilities.

  19. A survey of medical diagnostic imaging technologies

    SciTech Connect

    Heese, V.; Gmuer, N.; Thomlinson, W.

    1991-10-01

    The fields of medical imaging and medical imaging instrumentation are increasingly important. The state-of-the-art continues to advance at a very rapid pace. In fact, various medical imaging modalities are under development at the National Synchrotron Light Source (such as MECT and Transvenous Angiography.) It is important to understand how these techniques compare with today`s more conventional imaging modalities. The purpose of this report is to provide some basic information about the various medical imaging technologies currently in use and their potential developments as a basis for this comparison. This report is by no means an in-depth study of the physics and instrumentation of the various imaging modalities; instead, it is an attempt to provide an explanation of the physical bases of these techniques and their principal clinical and research capabilities.

  20. Transcranial Doppler ultrasound in neurovascular diseases: diagnostic and therapeutic aspects.

    PubMed

    Topcuoglu, M Akif

    2012-11-01

    Albeit no direct anatomical information can be obtained, neurosonological methods provide real-time determination of velocity, and spectral waveform of blood flow in basal intracranial arteries adds significant benefit to the care of the patients with neurovascular diseases. Several features, such as relative simplicity in terms of interpretation and performance, significantly low cost, totally non-invasiveness, portability, and excellent temporal resolution, make neurosonology increasingly popular tool for evaluation, planning, and monitoring of treatment, and for determining prognosis in various neurovascular diseases. Usefulness of transcranial Doppler in diagnosing/monitoring subarachnoid hemorrhage related vasospasm and sickle cell vasculopathy is already well known. Utility in diagnosis of intracranial arterial stenosis, acute occlusion and recanalization, intracranial hemodynamic effect of the cervical arterial pathologies, intracranial pressure increase, and cerebral circulatory arrest are also well established. Neurosonological determination of vasomotor reactivity, cerebral autoregulation, neurovascular coupling, and micro-embolic signals detection are useful in the assessment of stroke risk, diagnosis of right-to-left shunting, and monitoring during surgery and interventional procedures. Transcranial Doppler is also an evolving ultrasound method with a therapeutic potential such as augmentation of clot lysis and cerebral delivery of thrombolytic or neuroprotective agent loaded nanobubbles in neurovascular diseases. The aim of this study is to give an overview of current usage of the different ultrasound modalities in different neurovascular diseases. PMID:23050641

  1. Medical ultrasound: imaging of soft tissue strain and elasticity

    PubMed Central

    Wells, Peter N. T.; Liang, Hai-Dong

    2011-01-01

    After X-radiography, ultrasound is now the most common of all the medical imaging technologies. For millennia, manual palpation has been used to assist in diagnosis, but it is subjective and restricted to larger and more superficial structures. Following an introduction to the subject of elasticity, the elasticity of biological soft tissues is discussed and published data are presented. The basic physical principles of pulse-echo and Doppler ultrasonic techniques are explained. The history of ultrasonic imaging of soft tissue strain and elasticity is summarized, together with a brief critique of previously published reviews. The relevant techniques—low-frequency vibration, step, freehand and physiological displacement, and radiation force (displacement, impulse, shear wave and acoustic emission)—are described. Tissue-mimicking materials are indispensible for the assessment of these techniques and their characteristics are reported. Emerging clinical applications in breast disease, cardiology, dermatology, gastroenterology, gynaecology, minimally invasive surgery, musculoskeletal studies, radiotherapy, tissue engineering, urology and vascular disease are critically discussed. It is concluded that ultrasonic imaging of soft tissue strain and elasticity is now sufficiently well developed to have clinical utility. The potential for further research is examined and it is anticipated that the technology will become a powerful mainstream investigative tool. PMID:21680780

  2. Managing waiting times in diagnostic medical imaging

    PubMed Central

    Nuti, Sabina; Vainieri, Milena

    2012-01-01

    Objective This paper aims to analyse the variation in the delivery of diagnostic imaging services in order to suggest possible solutions for the reduction of waiting times, increase the quality of services and reduce financial costs. Design This study provides a logic model to manage waiting times in a regional context. Waiting times measured per day were compared on the basis of the variability in the use rates of CT and MRI examinations in Tuscany for the population, as well as on the basis of the capacity offered with respect to the number of radiologists available. The analysis was performed at the local health authority level to support the decision-making process of local managers. Setting Diagnostic imaging services, in particular the CT and MRI examinations. The study involved all the 12 local health authorities that provide services for 3.7 million inhabitants of the Italian Tuscany Region. Primary and secondary outcome measures Participants: the study uses regional administrative data on outpatients and survey data on inpatient diagnostic examinations in order to measure productivity. Primary and secondary outcome measures The study uses the volumes per 1000 inhabitants, the days of waiting times and the number of examinations per radiologist. Variability was measured using the traditional SD measures. Results A significant variation in areas considered homogeneous in terms of age, gender or mortality may indicate that the use of radiological services is not optimal and underuse or overuse occurs and that there is room for improvement in the service organisation. Conclusions Considering that there is a high level of variability among district use rates and waiting times, this study provides managers with a specific tool to find the cause of the problem, identify a possible solution, assess the financial impact and initiate the eventual reduction of waste. PMID:23242480

  3. Integration of Medical Imaging Including Ultrasound into a New Clinical Anatomy Curriculum

    ERIC Educational Resources Information Center

    Moscova, Michelle; Bryce, Deborah A.; Sindhusake, Doungkamol; Young, Noel

    2015-01-01

    In 2008 a new clinical anatomy curriculum with integrated medical imaging component was introduced into the University of Sydney Medical Program. Medical imaging used for teaching the new curriculum included normal radiography, MRI, CT scans, and ultrasound imaging. These techniques were incorporated into teaching over the first two years of the…

  4. Ultrasound

    MedlinePlus

    Ultrasound is a type of imaging. It uses high-frequency sound waves to look at organs and ... liver, and other organs. During pregnancy, doctors use ultrasound to view the fetus. Unlike x-rays, ultrasound ...

  5. Ultrasound

    MedlinePlus Videos and Cool Tools

    Ultrasound is a useful procedure for monitoring the baby's development in the uterus. Ultrasound uses inaudible sound waves to ... no known risks for ultrasound at present, it is highly recommended that pregnant women consult their physician ...

  6. Plasmonic nanoprobes: from chemical sensing to medical diagnostics and therapy

    NASA Astrophysics Data System (ADS)

    Vo-Dinh, Tuan; Fales, Andrew M.; Griffin, Guy D.; Khoury, Christopher G.; Liu, Yang; Ngo, Hoan; Norton, Stephen J.; Register, Janna K.; Wang, Hsin-Neng; Yuan, Hsiangkuo

    2013-10-01

    This article provides an overview of the development and applications of plasmonics-active nanoprobes in our laboratory for chemical sensing, medical diagnostics and therapy. Molecular Sentinel nanoprobes provide a unique tool for DNA/RNA biomarker detection both in a homogeneous solution or on a chip platform for medical diagnostics. The possibility of combining spectral selectivity and high sensitivity of the surface-enhanced Raman scattering (SERS) process with the inherent molecular specificity of nanoprobes provides an important multiplex diagnostic modality. Gold nanostars can provide an excellent multi-modality platform, combining two-photon luminescence with photothermal therapy as well as Raman imaging with photodynamic therapy. Several examples of optical detection using SERS and photonics-based treatments are presented to illustrate the usefulness and potential of the plasmonic nanoprobes for theranostics, which seamlessly combines diagnostics and therapy.

  7. Temperature measurement by thermal strain imaging with diagnostic power ultrasound, with potential for thermal index determination.

    PubMed

    Liang, Hai-Dong; Zhou, Li-Xia; Wells, Peter N T; Halliwell, Michael

    2009-05-01

    Over the years, there has been a substantial increase in acoustic exposure in diagnostic ultrasound as new imaging modalities with higher intensities and frame rates have been introduced; and more electronic components have been packed into the probe head, so that there is a tendency for it to become hotter. With respect to potential thermal effects, including those which may be hazardous occurring during ultrasound scanning, there is a correspondingly growing need for in vivo techniques to guide the operator as to the actual temperature rise occurring in the examined tissues. Therefore, an in vivo temperature estimator would be of considerable practical value. The commonly-used method of tissue thermal index (TI) measurement with a hydrophone in water could underestimate the actual value of TI (in one report by as much as 2.9 times). To obtain meaningful results, it is necessary to map the temperature elevation in 2-D (or 3-D) space. We present methodology, results and validation of a 2-D spatial and temporal thermal strain ultrasound temperature estimation technique in phantoms, and its apparently novel application in tracking the evolution of heat deposition at diagnostic exposure levels. The same ultrasound probe is used for both transmission and reception. The displacement and thermal strain estimation methods are similar to those used in high-intensity focused ultrasound thermal monitoring. The use of radiofrequency signals permits the application of cross correlation as a similarity measurement for tracking feature displacement. The displacement is used to calculate the thermal strain directly related to the temperature rise. Good agreement was observed between the temperature rise and the ultrasound power and scan duration. Thermal strain up to 1.4% was observed during 4000-s scan. Based on the results obtained for the temperature range studied in this work, the technique demonstrates potential for applicability in phantom (and possibly in vivo tissue

  8. Correlation of diagnostic ultrasound and radionuclide imaging in scrotal disease

    SciTech Connect

    Chen, D.C.P.; Holder, L.E.; Kaplan, G.N.

    1984-01-01

    A retrospective study was performed to evaluate the usefulness of scrotal ultrasound imaging (SU) and radionuclide scrotal imaging (RSI) in 43 patients (pts), age: 16-75. Twenty-two of them complained of scrotal pain; 18 had a scrotal mass; and 4 had a history of trauma. The final diagnoses were conformed by surgery (n = 21) and long-term follow-up (n = 22) and included 4 late phase and 1 early testicular torsion (TT), 11 acute epididymitis (AE), 4 subacute epididymitis (SE), 5 malignant tumors, 3 testicular atrophy, 2 intratesticular hematomas, 10 hydroceles or other cystic lesions, and miscellaneous. In pts with scrotal pain, 3/4 with late phase TT were correctly diagnosed, while one pt with early TT and 11/15 with AE or SE were not diagnosed by SU. All of them were correctly diagnosed with RSI except one with scrotal cyst. SU was able to separate cystic masses (n = 10) from solid masses (n = 6), but cannot separate malignant from benign lesions. SU was excellent in detecting 19 hydroceles and 2 intratesticular hematomas, while 3 lesions < 1 cm. were not seen in RSI. The authors concluded that SU is useful in pts with scrotal mass to separate solid from cystic lesions. However, SU is unable to differentiate the acute epididymitis from early testicular torsion. In pts with acute scrotal pain, SU is not helpful and RSI should still be the first study performed.

  9. The Diagnostic Value of Pelvic Ultrasound in Girls with Central Precocious Puberty

    PubMed Central

    Lee, Sang Heon; Joo, Eun Young; Jun, Yong-Hoon; Kim, Mi-Young

    2016-01-01

    The gonadotropin-releasing hormone (GnRH) stimulation test is the gold standard for differentiating central precocious puberty (CPP) from exaggerated thelarche (ET). Because of this test's limitations, previous studies have clarified the clinical and laboratory factors that predict CPP. The present study investigated the early diagnostic significance of pelvic ultrasound in girls with CPP. The GnRH stimulation test and pelvic ultrasound were performed between March 2007 and February 2015 in 192 girls (aged <8 years) with signs of early puberty and advanced bone age. Ninety-three of 192 patients (48.4%) were diagnosed as having CPP and the others (51.6%) as having ET. The CPP group had higher uterine volumes (4.31±2.79 mL) than did the ET group (3.05±1.97 mL, p=0.03). No significant differences were found in other ultrasonographic parameters. By use of receiver operating characteristic curve analysis, the most predictive parameter for CPP was a uterine volume of least 3.30 mL, with an area under the curve of 0.659 (95% confidence interval: 0.576-0.736). The CPP group had significantly higher uterine volumes than did the ET group, but there were no reliable cutoff values in pelvic ultrasound for differentiating between CPP and ET. Pelvic ultrasound should be combined with clinical and laboratory tests to maximize its diagnostic value for CPP. PMID:26866003

  10. Porphyria or Catatonia: Diagnostic Dilemma on the Medical Wards.

    PubMed

    Kurkjian, Natalie; Tucker, Phebe

    2016-01-01

    A 24-year-old Caucasian female, DD, was admitted to the medical service at an academic hospital with symptoms of weakness in bilateral lower extremities, falls, headaches, and altered mental status. Psychiatry was consulted to evaluate for psychiatric causes of her symptoms. This case presented a diagnostic challenge as the patient's identified symptoms changed almost daily, depending on what practitioner or medical service she encountered. In this study, we discuss the differential diagnoses, tests and treatments the patient received, with a review of literature helping differentiate between diagnostic parameters. PMID:27027143

  11. Endobronchial ultrasound: an unusual diagnostic tool for pulmonary embolism.

    PubMed

    Sariaydin, Muzaffer; Günay, Sibel; Günay, Ersin; Sarinc Ulasli, Sevinc

    2016-03-01

    Pulmonary thromboembolism (PTE) is an emergent and common pulmonary vascular disease. The most common diagnostic method for PTE is computer-aided tomography angiography. Endobronchial ultrasonography (EBUS) is used in diagnosis and staging of lung cancer via transbronchial needle aspiration from mediastinal lymphadenopathies and central masses. Diagnosis of PTE with EBUS is not common, although this technique helps to monitor pulmonary vasculature. The present case, a 60-year-old female patient to whom EBUS was applied because of mediastinal lymphadenopathy, was diagnosed as incidental PTE. PMID:26992367

  12. Using ultrasound to teach anatomy in the undergraduate medical curriculum: an evaluation of the experiences of tutors and medical students

    PubMed Central

    2014-01-01

    This paper describes the experiences of staff and students at two UK medical schools, who introduced portable ultrasound (PU) as an imaging technology to deliver clinical anatomy teaching and to aid skill development in interpretation of cross-sectional anatomy (CSA). A sonographer contributed to curriculum design and teaching, but mostly anatomy tutors delivered the teaching. This case study method evaluates staff and student perspectives on the ultrasound-based anatomy teaching. Quantitative data and qualitative data were collected and analysed. Staff were positive about the experience. They described their expectations for students and solutions for practical issues regarding the teaching, but were concerned about their competency in scanning and wanted bespoke training for sonoanatomy teaching. Curriculum development was accelerated through engagement with a sonographer and an ultrasound champion. Students were extremely positive about their experience; they valued the expertise of a sonographer who taught more challenging sonoanatomy, but were equally positive regarding teaching sessions led by well-trained anatomy tutors who taught more simple sonoanatomy. Students affirmed most tutors’ expectations that ultrasound could reinforce existing anatomical knowledge, added clinical contextualisation, but not that use of ultrasound (US) assisted in interpreting CSA. Students valued the introduction to the technology and found sonoimage interpretation challenging, but not insurmountable. Students wanted more instruction on ultrasound physics, an expansion of ultrasound curriculum, with smaller groups and opportunities to scan volunteers. These data support the case for the use of PU to deliver anatomy teaching and to prime medical students for later clinical encounters with PU.

  13. Ultrasound techniques in the evaluation of the mediastinum, part 2: mediastinal lymph node anatomy and diagnostic reach of ultrasound techniques, clinical work up of neoplastic and inflammatory mediastinal lymphadenopathy using ultrasound techniques and how to learn mediastinal endosonography

    PubMed Central

    Jenssen, Christian; Annema, Jouke Tabe; Clementsen, Paul; Cui, Xin-Wu; Borst, Mathias Maximilian

    2015-01-01

    Ultrasound imaging has gained importance in pulmonary medicine over the last decades including conventional transcutaneous ultrasound (TUS), endoscopic ultrasound (EUS), and endobronchial ultrasound (EBUS). Mediastinal lymph node (MLN) staging affects the management of patients with both operable and inoperable lung cancer (e.g., surgery vs. combined chemoradiation therapy). Tissue sampling is often indicated for accurate nodal staging. Recent international lung cancer staging guidelines clearly state that endosonography should be the initial tissue sampling test over surgical staging. Mediastinal nodes can be sampled from the airways [endobronchial ultrasound combined with transbronchial needle aspiration (EBUS-TBNA)] or the esophagus [endoscopic ultrasound fine needle aspiration (EUS-FNA)]. EBUS and EUS have a complementary diagnostic yield and in combination virtually all MLNs can be biopsied. Additionally endosonography has an excellent yield in assessing granulomas in patients suspected of sarcoidosis. The aim of this review in two integrative parts is to discuss the current role and future perspectives of all ultrasound techniques available for the evaluation of mediastinal lymphadenopathy and mediastinal staging of lung cancer. A specific emphasis will be on learning mediastinal endosonography. Part 1 deals with an introduction into ultrasound techniques, MLN anatomy and diagnostic reach of ultrasound techniques and part 2 with the clinical work up of neoplastic and inflammatory mediastinal lymphadenopathy using ultrasound techniques and how to learn mediastinal endosonography. PMID:26623120

  14. Effect of Watermarking on Diagnostic Preservation of Atherosclerotic Ultrasound Video in Stroke Telemedicine.

    PubMed

    Dey, Nilanjan; Bose, Soumyo; Das, Achintya; Chaudhuri, Sheli Sinha; Saba, Luca; Shafique, Shoaib; Nicolaides, Andrew; Suri, Jasjit S

    2016-04-01

    Embedding of diagnostic and health care information requires secure encryption and watermarking. This research paper presents a comprehensive study for the behavior of some well established watermarking algorithms in frequency domain for the preservation of stroke-based diagnostic parameters. Two different sets of watermarking algorithms namely: two correlation-based (binary logo hiding) and two singular value decomposition (SVD)-based (gray logo hiding) watermarking algorithms are used for embedding ownership logo. The diagnostic parameters in atherosclerotic plaque ultrasound video are namely: (a) bulb identification and recognition which consists of identifying the bulb edge points in far and near carotid walls; (b) carotid bulb diameter; and (c) carotid lumen thickness all along the carotid artery. The tested data set consists of carotid atherosclerotic movies taken under IRB protocol from University of Indiana Hospital, USA-AtheroPoint™ (Roseville, CA, USA) joint pilot study. ROC (receiver operating characteristic) analysis was performed on the bulb detection process that showed an accuracy and sensitivity of 100 % each, respectively. The diagnostic preservation (DPsystem) for SVD-based approach was above 99 % with PSNR (Peak signal-to-noise ratio) above 41, ensuring the retention of diagnostic parameter devalorization as an effect of watermarking. Thus, the fully automated proposed system proved to be an efficient method for watermarking the atherosclerotic ultrasound video for stroke application. PMID:26860914

  15. Low complex subspace minimum variance beamformer for medical ultrasound imaging.

    PubMed

    Deylami, Ali Mohades; Asl, Babak Mohammadzadeh

    2016-03-01

    Minimum variance (MV) beamformer enhances the resolution and contrast in the medical ultrasound imaging at the expense of higher computational complexity with respect to the non-adaptive delay-and-sum beamformer. The major complexity arises from the estimation of the L×L array covariance matrix using spatial averaging, which is required to more accurate estimation of the covariance matrix of correlated signals, and inversion of it, which is required for calculating the MV weight vector which are as high as O(L(2)) and O(L(3)), respectively. Reducing the number of array elements decreases the computational complexity but degrades the imaging resolution. In this paper, we propose a subspace MV beamformer which preserves the advantages of the MV beamformer with lower complexity. The subspace MV neglects some rows of the array covariance matrix instead of reducing the array size. If we keep η rows of the array covariance matrix which leads to a thin non-square matrix, the weight vector of the subspace beamformer can be achieved in the same way as the MV obtains its weight vector with lower complexity as high as O(η(2)L). More calculations would be saved because an η×L covariance matrix must be estimated instead of a L×L. We simulated a wire targets phantom and a cyst phantom to evaluate the performance of the proposed beamformer. The results indicate that we can keep about 16 from 43 rows of the array covariance matrix which reduces the order of complexity to 14% while the image resolution is still comparable to that of the standard MV beamformer. We also applied the proposed method to an experimental RF data and showed that the subspace MV beamformer performs like the standard MV with lower computational complexity. PMID:26678788

  16. [Nuclear medical diagnostics for liver tumors].

    PubMed

    Buck, A K; Stollfuss, J C; Stahl, A; Beer, A J; Meisetschläger, G; Schwaiger, M

    2007-01-01

    Standard nuclear medical procedures, such as functional, blood-pool and colloid scintigraphy, play a minor role in the routine workup of liver tumors. However, these techniques are capable of assessing specific organ functions and frequently allow the diagnosis of unclear liver lesions. The sensitivity of scintigraphic procedures can be increased using tomographic imaging (SPECT), the specificity with the introduction of hybrid scanners such as SPECT/CT. Whole body positron emission tomography with 18F-fluoro-deoxy-glucose (FDG) in combination with CT scanning (PET/CT) represents one of the most sensitive imaging modalities for the detection of hepatic metastases and extrahepatic tumor manifestations. For the staging and follow-up of colorectal cancer, FDG-PET/CT represents a standard imaging modality. Metastases from neuroendocrine tumors can be detected using PET and specific tracers such as [68Ga]DOTATOC and [18F]DOPA. Molecular imaging with PET allows the quantification of metabolic processes which can be used for the assessment of an early response to treatment. PMID:17195061

  17. Mammotome biopsy under ultrasound control in the diagnostics and treatment of nodular breast lesions - own experience.

    PubMed

    Kibil, Wojciech; Hodorowicz-Zaniewska, Diana; Kulig, Jan

    2012-05-01

    Mammotome biopsy is an effective, minimally invasive, novel technique used in the verification of breast lesions.The aim of the study was to assess the value of ultrasound-guided vacuum-assisted core needle biopsy (mammotome biopsy) in the diagnostics and treatment of nodular breast lesions, considering own data.Material and methods. Analysis comprised 1183 mammotome biopsies under ultrasound control performed in 1177 female patients during the period between 2000 and 2010, at the Regional Clinic for Early Diagnostics and Treatment of Breast Lesions, I Chair and Department of General Surgery, Jagiellonian University, Collegium Medicum.Results. The average patient age amounted to 41.7 years. The size of the investigated lesions ranged between 4 and 65 mm (mean - 12 mm). The histopathological examination result was as follows: fibrocystic lesions (n=285), adenofibroma (n=477), adenosis sclerosans (n=188), hyperplasia without atypy (n=58), phyllode tumor (n=2), papilloma (n=14), hamartoma (n=1), atypical hyperplasia (n=25), in situ ductal carcinoma (n=4), in situ lobular carcinoma (n=5), infiltrating ductal carcinoma (n=114), infiltrating lobular carcinoma (n=4), non-diagnostic result (n=6). The histopathological diagnosis was obtained in 99.5% of cases. Patients diagnosed with atypical hyperplasia or cancer were qualified for surgery, according to accepted standards. The presence of a hematoma was the most common complication after the biopsy, observed in 16.5% of patients.Conclusions. The obtained results confirmed the high value of ultrasound-guided biopsies in the diagnostics of nodular breast lesions. The method is safe, minimally invasive, with few complications, providing a good cosmetic effect. In case of benign lesions with a diameter of less than 15 mm the mammotome biopsy enables to completely excise the lesions, being an alternative to open surgical biopsies. The mammotome biopsy should become the method of choice considering the diagnostics of nodular

  18. An Interview with Medical Diagnostics Scientist Bernhard Weigl

    ERIC Educational Resources Information Center

    Sullivan, Megan

    2010-01-01

    Medical diagnostics help us evaluate a range of disorders, such as cancer and infectious diseases. In the United States and other developed countries, doctors have access to advanced equipment and laboratories that provide reliable diagnoses. As a result, when we are sick, we feel confident that we will get the treatment we need. Unfortunately,…

  19. 77 FR 39656 - Medical Diagnostic Equipment Accessibility Standards Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-05

    ... Proposed Rulemaking (NPRM) on Medical Diagnostic Equipment Accessibility Standards. See 77 FR 14706 (March.... In February 2012, the Access Board published an NPRM proposing the accessibility standards. See 77 FR..., Washington, DC 20004. FOR FURTHER INFORMATION CONTACT: Rex Pace, Office of Technical and Information...

  20. 78 FR 32612 - Medical Diagnostic Equipment Accessibility Standards Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-31

    ... Accessibility Standards. See 77 FR 6916 (February 9, 2012). The NPRM and information related to the proposed... translation (CART) web streaming link will be posted on the Access Board's Medical Diagnostic Equipment Web..., 1331 F Street NW., suite 1000, Washington, DC 20004- 1111. Telephone number (202) 272-0023...

  1. A specialized framework for Medical Diagnostic Knowledge Based Systems.

    PubMed Central

    Lanzola, G.; Stefanelli, M.

    1991-01-01

    To have a knowledge based system (KBS) exhibiting an intelligent behavior, it must be endowed even with knowledge able to represent the expert's strategies, other than with domain knowledge. The elicitation task is inherently difficult for strategic knowledge, because strategy is often tacit, and, even when it has been made explicit, it is not an easy task to describe it in a form that may be directly translated and implemented into a program. This paper describes a Specialized Framework for Medical Diagnostic Knowledge Based Systems able to help an expert in the process of building KBSs in a medical domain. The framework is based on an epistemological model of diagnostic reasoning which has proved to be helpful in describing the diagnostic process in terms of the tasks by which it is composed of. PMID:1807566

  2. Displacement analysis of diagnostic ultrasound backscatter: a methodology for characterizing, modeling, and monitoring high intensity focused ultrasound therapy.

    PubMed

    Speyer, Gavriel; Kaczkowski, Peter J; Brayman, Andrew A; Crum, Lawrence A

    2010-07-01

    Accurate monitoring of high intensity focused ultrasound (HIFU) therapy is critical for widespread clinical use. Pulse-echo diagnostic ultrasound (DU) is known to exhibit temperature sensitivity through relative changes in time-of-flight between two sets of radio frequency (RF) backscatter measurements, one acquired before and one after therapy. These relative displacements, combined with knowledge of the exposure protocol, material properties, heat transfer, and measurement noise statistics, provide a natural framework for estimating the administered heating, and thereby therapy. The proposed method, termed displacement analysis, identifies the relative displacements using linearly independent displacement patterns, or modes, each induced by a particular time-varying heating applied during the exposure interval. These heating modes are themselves linearly independent. This relationship implies that a linear combination of displacement modes aligning the DU measurements is the response to an identical linear combination of heating modes, providing the heating estimate. Furthermore, the accuracy of coefficient estimates in this approximation is determined a priori, characterizing heating, thermal dose, and temperature estimates for any given protocol. Predicted performance is validated using simulations and experiments in alginate gel phantoms. Evidence for a spatially distributed interaction between temperature and time-of-flight changes is presented. PMID:20649206

  3. Alteration of Bacterial Antibiotic Sensitivity After Short-Term Exposure to Diagnostic Ultrasound

    PubMed Central

    Mortazavi, Seyed Mohammad Javad; Darvish, Leili; Abounajmi, Mohammad; Zarei, Samira; Zare, Tahereh; Taheri, Mohammad; Nematollahi, Samaneh

    2015-01-01

    Background Many pathogenic bacteria show different levels of antibiotic resistance. Furthermore, a lot of hospital-acquired infections are caused by highly resistant or multidrug-resistant Gram-negative bacteria. According to WHO, patients with drug-resistant infections have higher morbidity and mortality. Moreover, patients infected with bacteria that are resistant to antibiotics considerably consume more healthcare resources. Objectives In this study, we explored a physical method of converting drug-resistant bacteria to drug-sensitive ones. Materials and Methods This is an in vitro case-control study, performed at the Ionizing and Non-ionizing Radiation Protection Research Center (INIRPRC), Shiraz University of Medical Sciences (SUMS), Shiraz, Iran in 2014. All experiments were carried out using Gram-negative bacteria Klebsiella pneumonia and E. coli and Gram-positive Staphylococcus aureus and Streptococcus group A, isolated from hospitalized patients. The bacterial strains were obtained from the Persian Type Culture Collection, IROST, Iran (Klebsiella pneumonia PTCC 1290) and Bacteriology Department of Shahid Faghihi Teaching Hospital, Shiraz, Iran (E. coli, Staphylococcus aureus, and Streptococcus group A). The bacteria in culture plates were exposed to diagnostic ultrasound using a MyLab70XVG sonography system for 5 minutes. Then, the bacteria were cultured on Mueller-Hinton agar and incubated at 35°C for 18 hours. Finally, antibiotic susceptibility test was performed and the inhibition zone in both control and exposed groups were measured. Three replicate agar plates were used for each test and the inhibition zones of the plates were recorded. Results Compared with the results obtained from unexposed bacteria, statistically significant variations of sensitivity to antibiotics were found in some strains after short-term exposure. In particular, we found major differences (making antibiotic-resistant bacteria susceptible or vice versa) in the diameters of

  4. Computerized Diagnostic Assistant for the Automatic Detection of Pneumothorax on Ultrasound: A Pilot Study

    PubMed Central

    Summers, Shane M.; Chin, Eric J.; Long, Brit J.; Grisell, Ronald D.; Knight, John G.; Grathwohl, Kurt W.; Ritter, John L.; Morgan, Jeffrey D.; Salinas, Jose; Blackbourne, Lorne H.

    2016-01-01

    Introduction Bedside thoracic ultrasound (US) can rapidly diagnose pneumothorax (PTX) with improved accuracy over the physical examination and without the need for chest radiography (CXR); however, US is highly operator dependent. A computerized diagnostic assistant was developed by the United States Army Institute of Surgical Research to detect PTX on standard thoracic US images. This computer algorithm is designed to automatically detect sonographic signs of PTX by systematically analyzing B-mode US video clips for pleural sliding and M-mode still images for the seashore sign. This was a pilot study to estimate the diagnostic accuracy of the PTX detection computer algorithm when compared to an expert panel of US trained physicians. Methods This was a retrospective study using archived thoracic US obtained on adult patients presenting to the emergency department (ED) between 5/23/2011 and 8/6/2014. Emergency medicine residents, fellows, attending physicians, physician assistants, and medical students performed the US examinations and stored the images in the picture archive and communications system (PACS). The PACS was queried for all ED bedside US examinations with reported positive PTX during the study period along with a random sample of negatives. The computer algorithm then interpreted the images, and we compared the results to an independent, blinded expert panel of three physicians, each with experience reviewing over 10,000 US examinations. Results Query of the PACS system revealed 146 bedside thoracic US examinations for analysis. Thirteen examinations were indeterminate and were excluded. There were 79 true negatives, 33 true positives, 9 false negatives, and 12 false positives. The test characteristics of the algorithm when compared to the expert panel were sensitivity 79% (95 % CI [63–89]) and specificity 87% (95% CI [77–93]). For the 20 images scored as highest quality by the expert panel, the algorithm demonstrated 100% sensitivity (95% CI [56

  5. Diagnostic yield of endobronchial ultrasound-guided transbronchial needle aspiration for mediastinal staging in lung cancer*

    PubMed Central

    Fernández-Bussy, Sebastián; Labarca, Gonzalo; Canals, Sofia; Caviedes, Iván; Folch, Erik; Majid, Adnan

    2015-01-01

    OBJECTIVE: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a minimally invasive diagnostic test with a high diagnostic yield for suspicious central pulmonary lesions and for mediastinal lymph node staging. The main objective of this study was to describe the diagnostic yield of EBUS-TBNA for mediastinal lymph node staging in patients with suspected lung cancer. METHODS: Prospective study of patients undergoing EBUS-TBNA for diagnosis. Patients ≥ 18 years of age were recruited between July of 2010 and August of 2013. We recorded demographic variables, radiological characteristics provided by axial CT of the chest, location of the lesion in the mediastinum as per the International Association for the Study of Lung Cancer classification, and definitive diagnostic result (EBUS with a diagnostic biopsy or a definitive diagnostic method). RESULTS: Our analysis included 354 biopsies, from 145 patients. Of those 145 patients, 54.48% were male. The mean age was 63.75 years. The mean lymph node size was 15.03 mm, and 90 lymph nodes were smaller than 10.0 mm. The EBUS-TBNA method showed a sensitivity of 91.17%, a specificity of 100.0%, and a negative predictive value of 92.9%. The most common histological diagnosis was adenocarcinoma. CONCLUSIONS: EBUS-TBNA is a diagnostic tool that yields satisfactory results in the staging of neoplastic mediastinal lesions. PMID:26176519

  6. [Ultrasound artifacts and their diagnostic significance in internal medicine and gastroenterology - Part 1: B-mode artifacts].

    PubMed

    Tuma, J; Jenssen, C; Möller, K; Cui, X W; Kinkel, H; Uebel, S; Dietrich, C F

    2016-05-01

    Artifacts in ultrasonographic diagnostics are a result of the physical properties of the ultrasound waves and are caused by interaction of the ultrasound waves with biological structures and tissues and with foreign bodies. On the one hand, they may be distracting and may lead to misdiagnosis. On the other hand, they may be diagnostically helpful. Ultrasound imaging suffers from artifacts, because in reality, parameters assumed to be constant values, such as sound speed, sound rectilinear propagation, attenuation, etc., are often different from the actual parameters. Moreover, inadequate device settings may cause artifacts. Profound knowledge of the causes, avoidance, and interpretation of artifacts is a necessary precondition for correct clinical appraisal of ultrasound images. Part 1 of this review comments on the physics of artifacts and describes the most important B-mode artifacts. Pitfalls, as well as diagnostic chances resulting from B-mode artifacts, are discussed. PMID:27171335

  7. Diagnostic ultrasound estimates of muscle mass and muscle quality discriminate between women with and without sarcopenia

    PubMed Central

    Ismail, Catheeja; Zabal, Johannah; Hernandez, Haniel J.; Woletz, Paula; Manning, Heather; Teixeira, Carla; DiPietro, Loretta; Blackman, Marc R.; Harris-Love, Michael O.

    2015-01-01

    Introduction: Age-related changes in muscle mass and muscle tissue composition contribute to diminished strength in older adults. The objectives of this study are to examine if an assessment method using mobile diagnostic ultrasound augments well-known determinants of lean body mass (LBM) to aid sarcopenia staging, and if a sonographic measure of muscle quality is associated with muscle performance. Methods: Twenty community-dwelling female subjects participated in the study (age = 43.4 ± 20.9 years; BMI: 23.8, interquartile range: 8.5). Dual energy X-ray absorptiometry (DXA) and diagnostic ultrasound morphometry were used to estimate LBM. Muscle tissue quality was estimated via the echogenicity using grayscale histogram analysis. Peak force was measured with grip dynamometry and scaled for body size. Bivariate and multiple regression analyses were used to determine the association of the predictor variables with appendicular lean mass (aLM/ht2), and examine the relationship between scaled peak force values and muscle echogenicity. The sarcopenia LBM cut point value of 6.75 kg/m2 determined participant assignment into the Normal LBM and Low LBM subgroups. Results: The selected LBM predictor variables were body mass index (BMI), ultrasound morphometry, and age. Although BMI exhibited a significant positive relationship with aLM/ht2 (adj. R2 = 0.61, p < 0.001), the strength of association improved with the addition of ultrasound morphometry and age as predictor variables (adj. R2 = 0.85, p < 0.001). Scaled peak force was associated with age and echogenicity (adj. R2 = 0.53, p < 0.001), but not LBM. The Low LBM subgroup of women (n = 10) had higher scaled peak force, lower BMI, and lower echogenicity values in comparison to the Normal LBM subgroup (n = 10; p < 0.05). Conclusions: Diagnostic ultrasound morphometry values are associated with LBM, and improve the BMI predictive model for aLM/ht2 in women. In addition, ultrasound proxy measures of muscle quality are more

  8. Development of a portable therapeutic and high intensity ultrasound system for military, medical, and research use.

    PubMed

    Lewis, George K; Olbricht, William L

    2008-11-01

    We have developed a portable high power ultrasound system with a very low output impedance amplifier circuit (less than 0.3 Omega) that can transfer more than 90% of the energy from a battery supply to the ultrasound transducer. The system can deliver therapeutic acoustical energy waves at lower voltages than those in conventional ultrasound systems because energy losses owing to a mismatched impedance are eliminated. The system can produce acoustic power outputs over the therapeutic range (greater then 50 W) from a PZT-4, 1.54 MHz, and 0.75 in diameter piezoelectric ceramic. It is lightweight, portable, and powered by a rechargeable battery. The portable therapeutic ultrasound unit has the potential to replace "plug-in" medical systems and rf amplifiers used in research. The system is capable of field service on its internal battery, making it especially useful for military, ambulatory, and remote medical applications. PMID:19045903

  9. Development of a portable therapeutic and high intensity ultrasound system for military, medical, and research use

    PubMed Central

    Lewis, George K.; Olbricht, William L.

    2008-01-01

    We have developed a portable high power ultrasound system with a very low output impedance amplifier circuit (less than 0.3 Ω) that can transfer more than 90% of the energy from a battery supply to the ultrasound transducer. The system can deliver therapeutic acoustical energy waves at lower voltages than those in conventional ultrasound systems because energy losses owing to a mismatched impedance are eliminated. The system can produce acoustic power outputs over the therapeutic range (greater then 50 W) from a PZT-4, 1.54 MHz, and 0.75 in diameter piezoelectric ceramic. It is lightweight, portable, and powered by a rechargeable battery. The portable therapeutic ultrasound unit has the potential to replace “plug-in” medical systems and rf amplifiers used in research. The system is capable of field service on its internal battery, making it especially useful for military, ambulatory, and remote medical applications. PMID:19045903

  10. Diagnostic sensitivity of ultrasound, radiography and computed tomography for gender determination in four species of lizards.

    PubMed

    Di Ianni, Francesco; Volta, Antonella; Pelizzone, Igor; Manfredi, Sabrina; Gnudi, Giacomo; Parmigiani, Enrico

    2015-01-01

    Gender determination is frequently requested by reptile breeders, especially for species with poor or absent sexual dimorphism. The aims of the current study were to describe techniques and diagnostic sensitivities of ultrasound, radiography, and computed tomography for gender determination (identification of hemipenes) in four species of lizards. Nineteen lizards of known sex, belonging to four different species (Pogona vitticeps, Uromastyx aegyptia, Tiliqua scincoides, Gerrhosaurus major) were prospectively enrolled. With informed owner consent, ultrasound, noncontrast CT, contrast radiography, and contrast CT (with contrast medium administered into the cloaca) were performed in conscious animals. Imaging studies were reviewed by three different operators, each unaware of the gender of the animals and of the results of the other techniques. The lizard was classified as a male when hemipenes were identified. Nineteen lizards were included in the study, 10 females and nine males. The hemipenes were seen on ultrasound in only two male lizards, and appeared as oval hypoechoic structures. Radiographically, hemipenes filled with contrast medium appeared as spindle-shaped opacities. Noncontrast CT identified hemipenes in only two lizards, and these appeared as spindle-shaped kinked structures with hyperattenuating content consistent with smegma. Hemipenes were correctly identified in all nine males using contrast CT (accuracy of 100%). Accuracy of contrast radiography was excellent (94.7%). Accuracy of ultrasound and of noncontrast CT was poor (64.3% and 63.1%, respectively). Findings from the current study supported the use of contrast CT or contrast radiography for gender determination in lizards. PMID:25065912

  11. Clinical benefits of combined diagnostic three-dimensional digital breast tomosynthesis and ultrasound imaging

    NASA Astrophysics Data System (ADS)

    Varjonen, Mari; Pamilo, Martti; Raulisto, Leena

    2005-04-01

    Our goal is to evaluate diagnostic digital breast tomosynthesis and ultrasound imaging clinical value in detecting and diagnosing early stage breast cancers. Determine if fusion imaging would decrease the number of biopsies and reduce further patient workup otherwise required to establish a definitive diagnosis. This paper presents the clinical results based on the study conducted at Helsinki University Central Hospital. Presentation demonstrates clinical dual modality images and results. Tomosynthesis of amorphous selenium based full field digital mammography system will be also presented. Forty asymptomatic women enrolled in the study based on prior identification of suspicious findings on screening mammograms where the possibility of breast cancer could not be excluded. Abnormal screening mammogram findings included tumor-like densities, parenchymal asymmetries and architectural distortions. Eight women were operated and 32 were not referred for surgery. Those cases, which were operated, three lesions represented ductal carcinoma in situ, two ductal carcinomas, one atypical ductal hyperplasia, one fibroadenoma and one radial scar. The 32 not operated cases revealed to be benign or superimposition of normal parenchymal breast tissue. The cases were returned to biennial screening. Ultrasound did not show clearly any lesions, but using tomosynthesis and ultrasound together we were able to analyze and locate the lesions exactly. Special tomosynthesis improves overall lesion detection and analysis. The value of tomosynthesis and ultrasound fusion imaging will be to provide additional clinical information in order to improve decision making accuracy to either confirm or exclude a suspected abnormality and in particular detect small breast cancers.

  12. Diagnostic value of contrast-enhanced ultrasound in solid thyroid nodules with and without enhancement.

    PubMed

    Wu, Qiong; Wang, Yan; Li, Yi; Hu, Bing; He, Zhi-Yan

    2016-08-01

    We aimed to investigate different enhancement patterns of solid thyroid nodules on contrast-enhanced ultrasound (CEUS) and then to evaluate the corresponding diagnostic performance in the differentiation of benign and malignant nodules with and without enhancement. 229 solid thyroid nodules in 196 patients who had undergone both conventional ultrasound and CEUS examinations were classified into enhancement and non-enhancement groups. Besides, different enhancement patterns in the enhancement group were characterised with five indicators including arrival time, mode of entrance, echo intensity, homogeneity, and washout time. Then aforementioned indicators were compared between benign and malignant nodules of different sizes (<10 mm and >10 mm), and diagnostic performance of significant enhancement indicators was calculated. As for the enhancement group, there were statistically significant differences of <10 mm subgroup among three CEUS indicators including arrival time, mode of entrance, and washout time between malignant and benign thyroid nodules (p < 0.05), while all CEUS indicators showed statistically significant differences in the total group and ≥10 mm subgroup (p < 0.05). All the five CEUS indicators displayed better diagnostic performance with specificity (92.86, 92.14, 95.71, 90.71, and 90.71 %, respectively) and diagnostic accuracy (80.79, 79.48, 74.67, 75.11, and 81.66 %, respectively), while the sensitivity and negative predictive value of non-enhancement were 95.51 and 95.83 %, respectively, with an accuracy of 77.29 %. CEUS is a very promising diagnostic technique that could improve the diagnostic accuracy of identifying benign thyroid lesions to spare a large number of patients an unnecessary invasive procedure. PMID:26732040

  13. Diagnostic computing: an elective for fourth-year medical students.

    PubMed

    Bartold, S; Hannigan, G G

    1995-01-01

    The complex problems that patients pose require familiarity with the use and limitations of diagnostic computer systems. Independent of practice specialty, physicians may expect to encounter computer applications and digital image systems to provide information for diagnosis and management. This poster describes an elective for fourth-year medical students that introduces students to diagnostic computing through the use of decision-assist software and imaging processing systems. The poster includes photographs, examples of course exercises and readings, and a summary of course evaluation information. PMID:8591394

  14. Ultrasound

    MedlinePlus

    Ultrasound uses high-frequency sound waves to make images of organs and structures inside the body. ... An ultrasound machine makes images so that organs inside the body can be examined. The machine sends out high- ...

  15. Computational Diagnostic: A Novel Approach to View Medical Data.

    SciTech Connect

    Mane, K. K.; Börner, K.

    2007-01-01

    A transition from traditional paper-based medical records to electronic health record is largely underway. The use of electronic records offers tremendous potential to personalize patient diagnosis and treatment. In this paper, we discuss a computational diagnostic tool that uses digital medical records to help doctors gain better insight about a patient's medical condition. The paper details different interactive features of the tool which offer potential to practice evidence-based medicine and advance patient diagnosis practices. The healthcare industry is a constantly evolving domain. Research from this domain is often translated into better understanding of different medical conditions. This new knowledge often contributes towards improved diagnosis and treatment solutions for patients. But the healthcare industry lags behind to seek immediate benefits of the new knowledge as it still adheres to the traditional paper-based approach to keep track of medical records. However recently we notice a drive that promotes a transition towards electronic health record (EHR). An EHR stores patient medical records in digital format and offers potential to replace the paper health records. Earlier attempts of an EHR replicated the paper layout on the screen, representation of medical history of a patient in a graphical time-series format, interactive visualization with 2D/3D generated images from an imaging device. But an EHR can be much more than just an 'electronic view' of the paper record or a collection of images from an imaging device. In this paper, we present an EHR called 'Computational Diagnostic Tool', that provides a novel computational approach to look at patient medical data. The developed EHR system is knowledge driven and acts as clinical decision support tool. The EHR tool provides two visual views of the medical data. Dynamic interaction with data is supported to help doctors practice evidence-based decisions and make judicious choices about patient

  16. Medical decision-making system of ultrasound carotid artery intima-media thickness using neural networks.

    PubMed

    Santhiyakumari, N; Rajendran, P; Madheswaran, M

    2011-12-01

    The objective of this work is to develop and implement a medical decision-making system for an automated diagnosis and classification of ultrasound carotid artery images. The proposed method categorizes the subjects into normal, cerebrovascular, and cardiovascular diseases. Two contours are extracted for each and every preprocessed ultrasound carotid artery image. Two types of contour extraction techniques and multilayer back propagation network (MBPN) system have been developed for classifying carotid artery categories. The results obtained show that MBPN system provides higher classification efficiency, with minimum training and testing time. The outputs of decision support system are validated with medical expert to measure the actual efficiency. MBPN system with contour extraction algorithms and preprocessing scheme helps in developing medical decision-making system for ultrasound carotid artery images. It can be used as secondary observer in clinical decision making. PMID:21181487

  17. The role of ultrasound and nuclear medicine methods in the preoperative diagnostics of primary hyperparathyroidism

    PubMed Central

    Cacko, Marek; Królicki, Leszek

    2015-01-01

    Primary hyperparathyroidism (PH) represents one of the most common endocrine diseases. In most cases, the disorder is caused by parathyroid adenomas. Bilateral neck exploration has been a widely used treatment method for adenomas since the 20's of the twentieth century. In the last decade, however, it has been increasingly replaced by a minimally invasive surgical treatment. Smaller extent, shorter duration and lower complication rate of such a procedure are emphasized. Its efficacy depends on a precise location of parathyroid tissue during the preoperative imaging. Scintigraphy and ultrasound play a major role in the diagnostic algorithms. The efficacy of both methods has been repeatedly verified and compared. The still-current guidelines of the European Association of Nuclear Medicine (2009) emphasize the complementary role of scintigraphy and ultrasonography in the preoperative diagnostics in patients with primary hyperparathyroidism. At the same time, attempts are made to improve both these techniques by implementing new study protocols or innovative technologies. Publications have emerged in the recent years in the field of ultrasonography, whose authors pointed out the usefulness of elastography and contrast media. Nuclear medicine studies, on the other hand, focus mainly on the assessment of new radiotracers used in the positron emission tomography (PET). The aim of this article is to present, based on literature data, the possibilities of ultrasound and scintigraphy in the preoperative diagnostics in patients with primary hyperparathyroidism. Furthermore, the main directions in the development of imaging techniques in PH patients were evaluated. PMID:26807297

  18. The role of ultrasound and nuclear medicine methods in the preoperative diagnostics of primary hyperparathyroidism.

    PubMed

    Nieciecki, Michał; Cacko, Marek; Królicki, Leszek

    2015-12-01

    Primary hyperparathyroidism (PH) represents one of the most common endocrine diseases. In most cases, the disorder is caused by parathyroid adenomas. Bilateral neck exploration has been a widely used treatment method for adenomas since the 20's of the twentieth century. In the last decade, however, it has been increasingly replaced by a minimally invasive surgical treatment. Smaller extent, shorter duration and lower complication rate of such a procedure are emphasized. Its efficacy depends on a precise location of parathyroid tissue during the preoperative imaging. Scintigraphy and ultrasound play a major role in the diagnostic algorithms. The efficacy of both methods has been repeatedly verified and compared. The still-current guidelines of the European Association of Nuclear Medicine (2009) emphasize the complementary role of scintigraphy and ultrasonography in the preoperative diagnostics in patients with primary hyperparathyroidism. At the same time, attempts are made to improve both these techniques by implementing new study protocols or innovative technologies. Publications have emerged in the recent years in the field of ultrasonography, whose authors pointed out the usefulness of elastography and contrast media. Nuclear medicine studies, on the other hand, focus mainly on the assessment of new radiotracers used in the positron emission tomography (PET). The aim of this article is to present, based on literature data, the possibilities of ultrasound and scintigraphy in the preoperative diagnostics in patients with primary hyperparathyroidism. Furthermore, the main directions in the development of imaging techniques in PH patients were evaluated. PMID:26807297

  19. Diagnostic Ultrasound High Mechanical Index Impulses Restore Microvascular Flow in Peripheral Arterial Thromboembolism.

    PubMed

    Porter, Thomas R; Radio, Stanley; Lof, John; Everbach, Carr; Powers, Jeffry E; Vignon, Francois; Shi, William T; Xie, Feng

    2016-07-01

    We sought to explore mechanistically how intermittent high-mechanical-index (MI) diagnostic ultrasound impulses restore microvascular flow. Thrombotic microvascular obstruction was created in the rat hindlimb muscle of 36 rats. A diagnostic transducer confirmed occlusion with low-MI imaging during an intravenous microbubble infusion. This same transducer was used to intermittently apply ultrasound with an MI that produced stable or inertial cavitation (IC) for 10 min through a tissue-mimicking phantom. A nitric oxide inhibitor, L-Nω-nitroarginine methyl ester (L-NAME), was pre-administered to six rats. Plateau microvascular contrast intensity quantified skeletal microvascular blood volume, and postmortem staining was used to detect perivascular hemorrhage. Intermittent IC impulses produced the greatest recovery of microvascular blood volume (p < 0.0001, analysis of variance). Nitric oxide inhibition did not affect the skeletal microvascular blood volume improvement, but did result in more perivascular hemorrhage. IC inducing pulses from a diagnostic transducer can reverse microvascular obstruction after acute arterial thromboembolism. Nitric oxide may prevent unwanted bio-effects of these IC pulses. PMID:27083977

  20. High-resolution medical ultrasound arrays using smart materials technology

    NASA Astrophysics Data System (ADS)

    Bridger, Keith; Caldwell, Paul J.; Kuhn, Phillip; Winzer, Stephen R.

    1996-05-01

    Current ultrasound images have relatively low contrast (high levels of clutter) and resolution. Image quality could be dramatically improved if 2D ultrasound transducer arrays were available to perform the scans. These improvements would come from reducing clutter by eliminating target echoes that the beam width of a 1D array causes to be superimposed on a scan plane, and enhancing resolution by enabling the use of algorithms which correct the wavefront distortion introduced by propagation through tissue. The advent of 2D arrays would also enable 3D images to be displayed--eventually in real time. The fabrication of 2D ultrasound arrays is, however, very difficult. This stems from the acoustic requirements of the array (aperture, pitch and element size) which combine together to dictate large numbers (> 1000) of very-low capacitance (< 10 pF) elements. The technology problems revolve around interconnecting the elements and reducing signal losses due to stray capacitance and impedance mismatch. This paper will show how the development of composite smart materials involving the integration of electromechanical elements with electronics is being extended to the development of relatively-inexpensive high-sensitivity 2D ultrasound arrays.

  1. [Pediatric patient sedation and analgesia for diagnostic medical procedures].

    PubMed

    Kadosaki, Mamoru

    2014-08-01

    There is an increasing demand for anesthesiologists to work outside the operating room in order to provide general anesthesia or monitored sedation for a variety of medical investigations or procedures in infants and children. The concept that treatment should be a pain- and stress-free experience is now well accepted, and this has placed additional responsibilities on anesthesiologists. We describe pediatric anesthesia and monitored sedation for diagnostic medical procedures. Children requiring a painful procedure and prolonged examination should be provided with optimal sedation and analgesia. The child should be monitored with standard ASA monitors. In the case of medical procedures such as gastrointestinal endoscopy, transesophageal echocardiography, and cardiac catheterization, general endotracheal anesthesia with neuromuscular block is recommended. Several short-acting anesthetic drugs, including sevoflurane, propofol, remifentanil, and rocuronium, have become available in Japan, and the safety and efficacy of pediatric general anesthesia for diagnostic medical procedures have improved. Infants who require a noninvasive and short examination may not be provided with anesthetics. The feed and wrap method is recommended. Satisfactory immobilization of the child during noninvasive medical procedures, including magnetic resonance imaging, may be achieved by intravenous sedation or general anesthesia. Monitored intravenous sedation using propofol is the most widely used for healthy children; general anesthesia with a laryngeal mask airway or endotracheal intubation and controlled ventilation is required for a critically ill child. PMID:25669029

  2. Conditionally Increased Acoustic Pressures in Nonfetal Diagnostic Ultrasound Examinations Without Contrast Agents: A Preliminary Assessment

    PubMed Central

    Nightingale, Kathryn R.; Church, Charles C.; Harris, Gerald; Wear, Keith A.; Bailey, Michael R.; Carson, Paul L.; Jiang, Hui; Sandstrom, Kurt L.; Szabo, Thomas L.; Ziskin, Marvin C.

    2016-01-01

    The mechanical index (MI) has been used by the US Food and Drug Administration (FDA) since 1992 for regulatory decisions regarding the acoustic output of diagnostic ultrasound equipment. Its formula is based on predictions of acoustic cavitation under specific conditions. Since its implementation over 2 decades ago, new imaging modes have been developed that employ unique beam sequences exploiting higher-order acoustic phenomena, and, concurrently, studies of the bioeffects of ultrasound under a range of imaging scenarios have been conducted. In 2012, the American Institute of Ultrasound in Medicine Technical Standards Committee convened a working group of its Output Standards Subcommittee to examine and report on the potential risks and benefits of the use of conditionally increased acoustic pressures (CIP) under specific diagnostic imaging scenarios. The term “conditionally” is included to indicate that CIP would be considered on a per-patient basis for the duration required to obtain the necessary diagnostic information. This document is a result of that effort. In summary, a fundamental assumption in the MI calculation is the presence of a preexisting gas body. For tissues not known to contain preexisting gas bodies, based on theoretical predications and experimentally reported cavitation thresholds, we find this assumption to be invalid. We thus conclude that exceeding the recommended maximum MI level given in the FDA guidance could be warranted without concern for increased risk of cavitation in these tissues. However, there is limited literature assessing the potential clinical benefit of exceeding the MI guidelines in these tissues. The report proposes a 3-tiered approach for CIP that follows the model for employing elevated output in magnetic resonance imaging and concludes with summary recommendations to facilitate Institutional Review Board (IRB)-monitored clinical studies investigating CIP in specific tissues. PMID:26112617

  3. The Resolution Integral – a tool for characterising the performance of diagnostic ultrasound scanners

    PubMed Central

    Inglis, Scott; Pye, Stephen D

    2014-01-01

    In this paper, we describe how the resolution integral can be used as a tool for characterising the grey-scale imaging of diagnostic ultrasound scanners. The definitions of resolution integral, characteristic resolution and depth of field are discussed in relation to grey-scale imaging performance, together with a method of measuring these parameters using the Edinburgh Pipe Phantom. We show how the characteristic resolution and depth of field can be used to quantify the differences between transducers designed for different applications and how they are useful in identifying and quantifying changes in the performance of individual transducers.

  4. Quantitative medical imaging: Initial studies of noncontact ultrasound applied to cortical bone phantoms

    NASA Astrophysics Data System (ADS)

    Halcrow, Peter William

    The purpose of this study was to take the initial steps towards applying Noncontact Ultrasound (NCU) to the in vivo monitoring of osteoporosis and to skeletal quantitative ultrasound imaging (QUS) using cortical bone phantoms. This project sought additional applications of NCU beyond its past limited usage in assessing third-degree burns. With this noncontact ultrasound imaging system, noncontact transducers and cortical bone phantoms with known bone mineral density (BMD) were used to determine speed of sound (SOS), integrated acoustical response (IR), and ultrasonic transmittance. Air gaps greater than 3 cm, two transmission and two reflection paths, and a digital signal processor were used to collect data. Significant correlations between BMD and measured SOS, IR, and transmittance were obtained. These NCU results were shown to be in agreement with results from contact ultrasound within 1-2%, which suggests that NCU might find additional applications in a clinical setting in the future in medical imaging.

  5. Development of distance accuracy measurement program for quality control of diagnostic ultrasound system

    NASA Astrophysics Data System (ADS)

    Kim, Yon-Min; Kim, Moon-Chan; Han, Dong-Kyoon; Cho, Jae-Hwan; Kim, Sang-Hyun

    2013-12-01

    Evaluating the performance of a diagnostic ultrasound system is important. Above all, establishing standards for such evaluations in an objective and systematic way is critical. However, quality control is currently measured based on subjective judgment of an observer. Against this background, this study intended to suggest quantified and objective data that would enable inter-observer variation to be overcome. Five radiological technologists used an ATS-539 multi-purpose ultrasound phantom to conduct measurements in the predetermined method. A digital imaging and communications in medicine (DICOM) standard image was obtained in an ultrasound system by using a self-developed software to measure the accuracy of the distance before the 95% confidence interval was calculated. In order to examine the accuracy of the distance in longitudinal and transverse measurements, we conducted t-tests to evaluate the significance for the results of quality control that was performed manually for the past one year and for the results of quality control that was performed by using software with the same equipment. For the longitudinal and the transverse measurements, the 95% confidence intervals were 100.96-101.29 mm and 83.18-84.26 mm, respectively. The computerized longitudinal measurement showed no significant difference from the manual measurement ( p > 0.05). The results of measurements using of software showed a higher reproducibility.

  6. Monitoring and guidance of minimally-invasive thermal therapy using diagnostic ultrasound.

    PubMed

    Ebbini, Emad S; Bischof, John C

    2009-01-01

    We present specialized ultrasound imaging modes for monitoring and guidance of noninvasive and minimally-invasive thermal therapy. One mode is based on two-dimensional imaging of temperature change using diagnostic ultrasound. We have validated this method both in vivo and in vitro in monitoring the heating patterns produced by noninvasive HIFU source and minimally-invasive RF ablation device, respectively. In addition, a nonlinear method for imaging the quadratic echo components from HIFU-induced lesions has also been developed and tested in vivo. Illustrative results from both modes of imaging are presented. These results demonstrate the unique advantages of ultrasound as an image-guidance modality. Specifically, the high spatial and temporal resolutions that allow for imaging highly-localized short-duration therapeutic and sub-therapeutic HIFU beams. With the advent of highperformance computing hardware, these imaging modes are now implementable in real-time. This will lead to active realtime monitoring and control of a range of thermal therapies in the very near future. PMID:19963819

  7. Ultrasound and stethoscope as tools in medical education and practice: considerations for the archives

    PubMed Central

    Fakoya, Francis A; du Plessis, Maira; Gbenimacho, Ikechi B

    2016-01-01

    Objectives In recent years, the use and portability of ultrasound has threatened the utility of the stethoscope, with many debating and even advocating its replacement. The authors set out to assess opinions in this regard among faculty within a medical school and specifically within an anatomy department where ultrasound is incorporated into the curriculum from the first term. Methods A debate was elicited during a biweekly Anatomy Journal Club session and was centered on three published papers presented. Several questions were raised regarding the possible replacement of stethoscope – the value of early exposure to students as well as how ultrasound and stethoscope should be considered by physicians, students, and teachers. Results The general consensus was that the stethoscope should not be replaced but should be used in conjunction with emerging portable ultrasound. Caution was given that technology could “overcomplicate” diagnosis and lead to increased tests resulting in increased cost of care. In terms of exposing students to ultrasound, just as the stethoscope requires practice to use effectively, so does the ultrasound and should be introduced as early on as possible. As is the case with the stethoscope, students may not initially appreciate all the finer details on ultrasound; however, continual use would improve skill. Conclusion The stethoscope should always remain part of the physical examination and ultrasound should be used in addition to, not replacement of. As technology advances the need for apprenticeship, training increases and students of the medical profession should be exposed to these technologies as early as possible. Hence, it is not yet time to archive the stethoscope. Perhaps never. PMID:27471420

  8. Diagnostic Accuracy of Ultrasound B scan using 10 MHz linear probe in ocular trauma;results from a high burden country

    PubMed Central

    Shazlee, Muhammad Kashif; Ali, Muhammad; SaadAhmed, Muhammad; Hussain, Ammad; Hameed, Kamran; Lutfi, Irfan Amjad; Khan, Muhammad Tahir

    2016-01-01

    Objective: To study the diagnostic accuracy of Ultrasound B scan using 10 MHz linear probe in ocular trauma. Methods: A total of 61 patients with 63 ocular injuries were assessed during July 2013 to January 2014. All patients were referred to the department of Radiology from Emergency Room since adequate clinical assessment of the fundus was impossible because of the presence of opaque ocular media. Based on radiological diagnosis, the patients were provided treatment (surgical or medical). Clinical diagnosis was confirmed during surgical procedures or clinical follow-up. Results: A total of 63 ocular injuries were examined in 61 patients. The overall sensitivity was 91.5%, Specificity was 98.87%, Positive predictive value was 87.62 and Negative predictive value was 99%. Conclusion: Ultrasound B-scan is a sensitive, non invasive and rapid way of assessing intraocular damage caused by blunt or penetrating eye injuries. PMID:27182245

  9. Comparison of Diagnostic Performance of Semi-Quantitative Knee Ultrasound and Knee Radiography with MRI: Oulu Knee Osteoarthritis Study.

    PubMed

    Podlipská, Jana; Guermazi, Ali; Lehenkari, Petri; Niinimäki, Jaakko; Roemer, Frank W; Arokoski, Jari P; Kaukinen, Päivi; Liukkonen, Esa; Lammentausta, Eveliina; Nieminen, Miika T; Tervonen, Osmo; Koski, Juhani M; Saarakkala, Simo

    2016-01-01

    Osteoarthritis (OA) is a common degenerative musculoskeletal disease highly prevalent in aging societies worldwide. Traditionally, knee OA is diagnosed using conventional radiography. However, structural changes of articular cartilage or menisci cannot be directly evaluated using this method. On the other hand, ultrasound is a promising tool able to provide direct information on soft tissue degeneration. The aim of our study was to systematically determine the site-specific diagnostic performance of semi-quantitative ultrasound grading of knee femoral articular cartilage, osteophytes and meniscal extrusion, and of radiographic assessment of joint space narrowing and osteophytes, using MRI as a reference standard. Eighty asymptomatic and 79 symptomatic subjects with mean age of 57.7 years were included in the study. Ultrasound performed best in the assessment of femoral medial and lateral osteophytes, and medial meniscal extrusion. In comparison to radiography, ultrasound performed better or at least equally well in identification of tibio-femoral osteophytes, medial meniscal extrusion and medial femoral cartilage morphological degeneration. Ultrasound provides relevant additional diagnostic information on tissue-specific morphological changes not depicted by conventional radiography. Consequently, the use of ultrasound as a complementary imaging tool along with radiography may enable more accurate and cost-effective diagnostics of knee osteoarthritis at the primary healthcare level. PMID:26926836

  10. Comparison of Diagnostic Performance of Semi-Quantitative Knee Ultrasound and Knee Radiography with MRI: Oulu Knee Osteoarthritis Study

    PubMed Central

    Podlipská, Jana; Guermazi, Ali; Lehenkari, Petri; Niinimäki, Jaakko; Roemer, Frank W.; Arokoski, Jari P.; Kaukinen, Päivi; Liukkonen, Esa; Lammentausta, Eveliina; Nieminen, Miika T.; Tervonen, Osmo; Koski, Juhani M.; Saarakkala, Simo

    2016-01-01

    Osteoarthritis (OA) is a common degenerative musculoskeletal disease highly prevalent in aging societies worldwide. Traditionally, knee OA is diagnosed using conventional radiography. However, structural changes of articular cartilage or menisci cannot be directly evaluated using this method. On the other hand, ultrasound is a promising tool able to provide direct information on soft tissue degeneration. The aim of our study was to systematically determine the site-specific diagnostic performance of semi-quantitative ultrasound grading of knee femoral articular cartilage, osteophytes and meniscal extrusion, and of radiographic assessment of joint space narrowing and osteophytes, using MRI as a reference standard. Eighty asymptomatic and 79 symptomatic subjects with mean age of 57.7 years were included in the study. Ultrasound performed best in the assessment of femoral medial and lateral osteophytes, and medial meniscal extrusion. In comparison to radiography, ultrasound performed better or at least equally well in identification of tibio-femoral osteophytes, medial meniscal extrusion and medial femoral cartilage morphological degeneration. Ultrasound provides relevant additional diagnostic information on tissue-specific morphological changes not depicted by conventional radiography. Consequently, the use of ultrasound as a complementary imaging tool along with radiography may enable more accurate and cost-effective diagnostics of knee osteoarthritis at the primary healthcare level. PMID:26926836

  11. [Ultrasound artifacts and their diagnostic significance in internal medicine and gastroenterology - part 2: color and spectral Doppler artifacts].

    PubMed

    Jenssen, C; Tuma, J; Möller, K; Cui, X W; Kinkel, H; Uebel, S; Dietrich, C F

    2016-06-01

    Artifacts in ultrasonographic diagnostics are a result of the physical properties of the ultrasound waves and are caused by interaction of the ultrasound waves with biological structures and tissues of the body and with foreign materials. On the one hand, they may be diagnostically helpful. On the other hand, they may be distracting and may lead to misdiagnosis. Profound knowledge of the causes, avoidance, and interpretation of artifacts is a necessary precondition for correct clinical appraisal of ultrasound images. Part 1 of this review commented on the physics of artifacts and described the most important B-mode artifacts. Part 2 focuses on the clinically relevant artifacts in Doppler and color-coded duplex sonography. Problems and pitfalls of interpretation arising from artifacts, as well as the diagnostic use of Doppler and colour-coded duplex sonography, are discussed. PMID:27284933

  12. 3D freehand ultrasound for medical assistance in diagnosis and treatment of breast cancer: preliminary results

    NASA Astrophysics Data System (ADS)

    Torres, Fabian; Fanti, Zian; Arambula Cosío, F.

    2013-11-01

    Image-guided interventions allow the physician to have a better planning and visualization of a procedure. 3D freehand ultrasound is a non-invasive and low-cost imaging tool that can be used to assist medical procedures. This tool can be used in the diagnosis and treatment of breast cancer. There are common medical practices that involve large needles to obtain an accurate diagnosis and treatment of breast cancer. In this study we propose the use of 3D freehand ultrasound for planning and guiding such procedures as core needle biopsy and radiofrequency ablation. The proposed system will help the physician to identify the lesion area, using image-processing techniques in the 3D freehand ultrasound images, and guide the needle to this area using the information of position and orientation of the surgical tools. We think that this system can upgrade the accuracy and efficiency of these procedures.

  13. In vivo gas body efficacy for glomerular capillary hemorrhage induced by diagnostic ultrasound in rats.

    PubMed

    Miller, Douglas L; Dou, Chunyan; Wiggins, Roger C

    2010-01-01

    Glomerular capillary hemorrhage (GCH) in rat kidney provided a model for assessing in vivo gas body efficacy in diagnostic or therapeutic applications of ultrasound. Two diagnostic ultrasound machines were utilized: one monitored the harmonic B-mode contrast enhancement of the left kidney and the other exposed the right kidney for GCH production. Definity contrast agent was infused at 1, 2, 5, or 10 microL/(kg x min) and infusion durations were 30, 60, 120, or 300 s. Exposure of the right kidney was at a peak rarefactional pressure amplitude of 2.3 MPa at 1.5 MHz. The circulating dose was estimated with a simple model of agent dilution and gas body loss. For 300 s infusion at 5 microL/(kg x min), the left kidney image brightness increased to a plateau with an estimated 6.4 +/- 1.3 microL/kg circulating dose with no GCH in histological sections. Exposure of the right kidney with a 1-s image interval reduced the estimated circulating dose to 1.3 +/- 0.3 microL/kg and induced 68.4% GCH. Dose and duration increases gave rapidly diminishing treatment effectiveness per gas body. The effective in vivo agent dose in rats can be reduced greatly due to high gas body destruction in the small animal, complicating predictions for similar conditions of human treatment. PMID:19709948

  14. In Vivo Gas Body Efficacy for Glomerular Capillary Hemorrhage Induced by Diagnostic Ultrasound in Rats

    PubMed Central

    Miller, Douglas L.; Dou, Chunyan; Wiggins, Roger C.

    2009-01-01

    Glomerular capillary hemorrhage (GCH) in rat kidney provided a model for assessing in vivo gas body efficacy in diagnostic or therapeutic applications of ultrasound. Two diagnostic ultrasound machines were utilized: one monitored the harmonic B-mode contrast-enhancement of the left kidney and the other exposed the right kidney for GCH production. Definity contrast agent was infused at 1, 2, 5 or 10 μl/kg/min and infusion durations were 30, 60, 120 or 300 s. Exposure of the right kidney was at a peak rarefactional pressure amplitude of 2.3 MPa at 1.5 MHz. The circulating dose was estimated with a simple model of agent dilution and gas body loss. For 300 s infusion at 5 μl/kg/min, the left kidney image brightness increased to a plateau with an estimated 6.4±1.3 μl/kg circulating dose with no GCH in histological sections. Exposure of the right kidney with a 1 s image interval reduced the estimated circulating dose to 1.3±0.3 μl/kg and induced 68.4 % GCH. Dose and duration increases gave rapidly diminishing treatment effectiveness per gas body. The effective in vivo agent dose in rats can be reduced greatly due to high gas body destruction in the small animal, complicating predictions for similar conditions of human treatment. PMID:19709948

  15. High-resolution, low-delay, and error-resilient medical ultrasound video communication using H.264/AVC over mobile WiMAX networks.

    PubMed

    Panayides, Andreas; Antoniou, Zinonas C; Mylonas, Yiannos; Pattichis, Marios S; Pitsillides, Andreas; Pattichis, Constantinos S

    2013-05-01

    In this study, we describe an effective video communication framework for the wireless transmission of H.264/AVC medical ultrasound video over mobile WiMAX networks. Medical ultrasound video is encoded using diagnostically-driven, error resilient encoding, where quantization levels are varied as a function of the diagnostic significance of each image region. We demonstrate how our proposed system allows for the transmission of high-resolution clinical video that is encoded at the clinical acquisition resolution and can then be decoded with low-delay. To validate performance, we perform OPNET simulations of mobile WiMAX Medium Access Control (MAC) and Physical (PHY) layers characteristics that include service prioritization classes, different modulation and coding schemes, fading channels conditions, and mobility. We encode the medical ultrasound videos at the 4CIF (704 × 576) resolution that can accommodate clinical acquisition that is typically performed at lower resolutions. Video quality assessment is based on both clinical (subjective) and objective evaluations. PMID:23232416

  16. A computerized data base system for medical diagnostic studies (Diastu).

    PubMed

    Rosen, I I; Hall, T C; Mettler, F; Wicks, J; Kelsey, C A; Gustafson, D E

    1980-12-01

    A computerized database system (DIASTU) has been developed for the storage and selective retrieval of the results of medical diagnostic studies. The system is being used to analyze the disease process and the efficacy and yield of selected diagnostic studies. The system runs on a DEC PDP-11/60 computer. It consists of three FORTRAN IV programs linked to a general-purpose assembly language database handler. One program, DSENT, interactively modifies the information in the database. The second, DSLIST, prints all or portions of the database. The third program, DSTAT, interactively assembles the parameters for selective searches of the database and executes them. A query language is used that allows the use of time and size specifications and Boolean operators in nested loops. PMID:7249603

  17. Hazard analysis of a computer based medical diagnostic system.

    PubMed

    Chudleigh, M F

    1994-07-01

    Medical screening of sectors of the population is now a routine and vital part of health care: an example is cervical smear testing. There is currently significant interest in the possible introduction of semi-automated microscopy systems for cervical cytology and one such experimental system is now undergoing laboratory trials. A collaborative project has been set up to demonstrate the benefits and constraints that arise from applying safety-critical methods developed in other domains to such a diagnostic system. We have carried out a system hazard analysis, successfully using the HAZOP technique adapted from the petrochemical industry. PMID:7988111

  18. Distributed Network, Wireless and Cloud Computing Enabled 3-D Ultrasound; a New Medical Technology Paradigm

    PubMed Central

    Meir, Arie; Rubinsky, Boris

    2009-01-01

    Medical technologies are indispensable to modern medicine. However, they have become exceedingly expensive and complex and are not available to the economically disadvantaged majority of the world population in underdeveloped as well as developed parts of the world. For example, according to the World Health Organization about two thirds of the world population does not have access to medical imaging. In this paper we introduce a new medical technology paradigm centered on wireless technology and cloud computing that was designed to overcome the problems of increasing health technology costs. We demonstrate the value of the concept with an example; the design of a wireless, distributed network and central (cloud) computing enabled three-dimensional (3-D) ultrasound system. Specifically, we demonstrate the feasibility of producing a 3-D high end ultrasound scan at a central computing facility using the raw data acquired at the remote patient site with an inexpensive low end ultrasound transducer designed for 2-D, through a mobile device and wireless connection link between them. Producing high-end 3D ultrasound images with simple low-end transducers reduces the cost of imaging by orders of magnitude. It also removes the requirement of having a highly trained imaging expert at the patient site, since the need for hand-eye coordination and the ability to reconstruct a 3-D mental image from 2-D scans, which is a necessity for high quality ultrasound imaging, is eliminated. This could enable relatively untrained medical workers in developing nations to administer imaging and a more accurate diagnosis, effectively saving the lives of people. PMID:19936236

  19. Distributed network, wireless and cloud computing enabled 3-D ultrasound; a new medical technology paradigm.

    PubMed

    Meir, Arie; Rubinsky, Boris

    2009-01-01

    Medical technologies are indispensable to modern medicine. However, they have become exceedingly expensive and complex and are not available to the economically disadvantaged majority of the world population in underdeveloped as well as developed parts of the world. For example, according to the World Health Organization about two thirds of the world population does not have access to medical imaging. In this paper we introduce a new medical technology paradigm centered on wireless technology and cloud computing that was designed to overcome the problems of increasing health technology costs. We demonstrate the value of the concept with an example; the design of a wireless, distributed network and central (cloud) computing enabled three-dimensional (3-D) ultrasound system. Specifically, we demonstrate the feasibility of producing a 3-D high end ultrasound scan at a central computing facility using the raw data acquired at the remote patient site with an inexpensive low end ultrasound transducer designed for 2-D, through a mobile device and wireless connection link between them. Producing high-end 3D ultrasound images with simple low-end transducers reduces the cost of imaging by orders of magnitude. It also removes the requirement of having a highly trained imaging expert at the patient site, since the need for hand-eye coordination and the ability to reconstruct a 3-D mental image from 2-D scans, which is a necessity for high quality ultrasound imaging, is eliminated. This could enable relatively untrained medical workers in developing nations to administer imaging and a more accurate diagnosis, effectively saving the lives of people. PMID:19936236

  20. Ultrasound

    MedlinePlus

    ... please enable JavaScript. Ultrasound uses high-frequency sound waves to make images of organs and structures inside ... examined. The machine sends out high-frequency sound waves, which reflect off body structures. A computer receives ...

  1. The Role of Anthropomorphic Phantoms in Diagnostic Ultrasound Imaging for Disease Characterization (abstract)

    NASA Astrophysics Data System (ADS)

    Cannon, L. M.; King, D. M.; Browne, J. E.

    2009-04-01

    An anthropomorhic phantom is an object that can mimic a region of the human anatomy. Anthropomorphic phantoms have a variety of roles in diagnostic ultrasound. These roles include quality assurance testing of ultrasound machines, calibration and testing of new imaging techniques, training of sonographers, and-most importantly-use as a tool to obtain a better understanding of disease progression in the relevant anatomy. To be anthropomorphic a phantom must accurately mimic the body in terms of its ultrasonic and mechanical properties, as well as anatomically. The acoustic properties are speed of sound, attenuation, and backscatter. The mechanical properties are elasticity and density. Phantoms are constructed from tissue-mimicking materials (TMMs). TMMs are prepared from a variety of ingredients, such as gelatine, agar, safflower oil, and glass beads. These ingredients are then boiled and cooled under controlled conditions to produce a solid TMM. To determine if the TMM has the correct acoustic properties, acoustic measurements are performed using a scanning acoustic macroscope. Mechanical measurements are also performed to test the elasticity and density properties. TMMs with the correct properties are subsequently put through a series of moulding procedures to produce the anthropomorphic phantom.

  2. Prenatal diagnostic testing of the Noonan syndrome genes in fetuses with abnormal ultrasound findings.

    PubMed

    Croonen, Ellen A; Nillesen, Willy M; Stuurman, Kyra E; Oudesluijs, Gretel; van de Laar, Ingrid M B M; Martens, Liesbeth; Ockeloen, Charlotte; Mathijssen, Inge B; Schepens, Marga; Ruiterkamp-Versteeg, Martina; Scheffer, Hans; Faas, Brigitte H W; van der Burgt, Ineke; Yntema, Helger G

    2013-09-01

    In recent studies on prenatal testing for Noonan syndrome (NS) in fetuses with an increased nuchal translucency (NT) and a normal karyotype, mutations have been reported in 9-16% of cases. In this study, DNA of 75 fetuses with a normal karyotype and abnormal ultrasound findings was tested in a diagnostic setting for mutations in (a subset of) the four most commonly mutated NS genes. A de novo mutation in either PTPN11, KRAS or RAF1 was detected in 13 fetuses (17.3%). Ultrasound findings were increased NT, distended jugular lymphatic sacs (JLS), hydrothorax, renal anomalies, polyhydramnios, cystic hygroma, cardiac anomalies, hydrops fetalis and ascites. A second group, consisting of anonymized DNA of 60 other fetuses with sonographic abnormalities, was tested for mutations in 10 NS genes. In this group, five possible pathogenic mutations have been identified (in PTPN11 (n=2), RAF1, BRAF and MAP2K1 (each n=1)). We recommend prenatal testing of PTPN11, KRAS and RAF1 in pregnancies with an increased NT and at least one of the following additional features: polyhydramnios, hydrops fetalis, renal anomalies, distended JLS, hydrothorax, cardiac anomalies, cystic hygroma and ascites. If possible, mutation analysis of BRAF and MAP2K1 should be considered. PMID:23321623

  3. The significance of the ultrasound diagnostics in evaluation of the emboligenic pathogenesis of transient ischemic attacks.

    PubMed

    Jovanović, Z B; Pavlović, M A; Vujisić Tešić, P B; Boričić Kostić, V M; Cvitan, Ž E; Pekmezović, P T; Šternić Čovičković, M N; Zagorka, Jovanović B; Aleksandra, Pavlović M; Bosiljka, Vujisić Tešić P; Marija, Boričić Kostić V; Edita, Cvitan Ž; Tatjana, Pekmezović P; Nadežda, Sternić Čovičković M

    2013-04-01

    The objective of this study was to examine the possibilities of ultrasound diagnostics in the evaluation of emboligenic pathogenesis of transient ischemic attacks (TIAs) and the frequency of specific origins of embolism. A total of 150 adult patients with TIA and 50 control patients, were examined by neurosonologic, echocardiographic and venous ultrasound examination. Emboligenic pathogenesis of TIA was established in 36.6% of patients. Microembolic signals were detected in 22.7% of the whole group, and 61.8% in emboligenic TIA subgroup. Artery-to-artery embolism from ulcerated plaque of the carotid arteries was found in 12.6% of patients, from the aortic arch atheroma in 3.3% and cardioembolism in 12.6% (atrial fibrillation 7.3%, atrial septal aneurysm 2%, mitral valve prolapse 2%, mechanical heart valve 0.7%, left atrium thrombus 0.7%). Paradoxic embolism with the patent foramen ovale was established in 6% of patients, and with the pulmonary right-to-left shunt in 2%. Correlation with controls showed significantly higher frequency of the ulcerated carotid plaque and frequency of microembolic signals in the TIA group (p < 0.05). The patients with potential sources of embolism had a greater risk of developing TIA than those without these sources. PMID:23384465

  4. Influence of Scan Duration on Pulmonary Capillary Hemorrhage Induced by Diagnostic Ultrasound.

    PubMed

    Miller, Douglas L; Dong, Zhihong; Dou, Chunyan; Raghavendran, Krishnan

    2016-08-01

    Diagnostic ultrasound can induce pulmonary capillary hemorrhage (PCH) in rats and display this as "comet tail" artifacts (CTAs) after a time delay. To test the hypothesis that no PCH occurs for brief scans, anesthetized rats were scanned using a 6-MHz linear array for different durations. PCH was characterized by ultrasound CTAs, micro-computed tomography (μCT), and measurements of fixed lung tissue. The μCT images revealed regions of PCH, sometimes penetrating the entire depth of a lobe, which were reflected in the fixed tissue measurements. At -3 dB of power, PCH was substantial for 300-s scans, but not significant for 25-s scans. At 0 dB, PCH was not strongly dependent on scan durations of 300 to 10 s. Contrary to the hypothesis, CTAs were not evident during most 10-s scans (p > 0.05), but PCH was significant (p = 0.02), indicating that PCH could occur without evidence of the injury in the images. PMID:27117631

  5. The Role of Anthropomorphic Phantoms in Diagnostic Ultrasound Imaging for Disease Characterization

    SciTech Connect

    Cannon, L. M.; King, D. M.; Browne, J. E.

    2009-04-19

    An anthropomorhic phantom is an object that can mimic a region of the human anatomy. Anthropomorphic phantoms have a variety of roles in diagnostic ultrasound. These roles include quality assurance testing of ultrasound machines, calibration and testing of new imaging techniques, training of sonographers, and--most importantly--use as a tool to obtain a better understanding of disease progression in the relevant anatomy. To be anthropomorphic a phantom must accurately mimic the body in terms of its ultrasonic and mechanical properties, as well as anatomically. The acoustic properties are speed of sound, attenuation, and backscatter. The mechanical properties are elasticity and density. Phantoms are constructed from tissue-mimicking materials (TMMs). TMMs are prepared from a variety of ingredients, such as gelatine, agar, safflower oil, and glass beads. These ingredients are then boiled and cooled under controlled conditions to produce a solid TMM. To determine if the TMM has the correct acoustic properties, acoustic measurements are performed using a scanning acoustic macroscope. Mechanical measurements are also performed to test the elasticity and density properties. TMMs with the correct properties are subsequently put through a series of moulding procedures to produce the anthropomorphic phantom.

  6. The Speckle Noise Reduction and the Boundary Enhancement on Medical Ultrasound Images using the Cellular Neural Networks

    NASA Astrophysics Data System (ADS)

    Park, Hyunkyung; Miyazaki, Ryota; Nishimura, Toshihiro; Tamaki, Yasuhiro

    The purpose is to remove the speckle noise and to emphasize the boundary of a tumor by filtering based on the intensity difference in the medical ultrasound images. The proposed method is evaluated using numerical phantom simulating ultrasound B-mode images, and the effect is confirmed by applying to medical ultrasound images. Therefore, some important features such as tissue boundaries and small tumors may be overlooked. A CNN (cellular neural networks) for the speckle reduction and the edge enhancement are proposed in this paper. A CNN which is a kind of recurrent neural network can deal with images by the weight of neurons called a cell. It could be obtained more detail images recognition compared with the previous studies. A determination template parameters of the CNN for ultrasound image processing is discussed. The experimental results show effectiveness of applying the proposed method to boundary enhancement and the speckle reduction of medical ultrasound image.

  7. Educating the future sonographic workforce: membership survey report from the British Medical Ultrasound Society.

    PubMed

    Parker, P C; Harrison, G

    2015-11-01

    The British Medical Ultrasound Society (BMUS), the Consortium for the Accreditation of Sonographic Education (CASE), education providers and the NHS are working together to review how best to develop education for the future sonographic workforce. There is currently a national vacancy rate of approximately 12% across NHS Trusts. Education course placements are often limited to the number of clinical training places available within departments, resulting in a disparity between vacancies and the numbers of qualified sonographers graduating. Clearly there is a need for education to match the service demand. A term often used as a solution to the workforce problem is 'direct entry' ultrasound education. Anecdotally this term has caused confusion amongst health care professionals and as such the aim of this work was to gain an understanding of the views and opinions of BMUS members and interested professionals about direct entry training and subsequent development of any future training programmes. BMUS undertook an online survey with 286 responses. The survey provided insight into the opinions of ultrasound practitioners and the complexities of developing a relevant educational programme for the future sonographer workforce. The results suggested a number of concerns with direct entry ultrasound programmes, including insufficient training places, lack of health care background knowledge, lack of imaging knowledge and no state registration specific to sonographers. Benefits of direct entry to ultrasound training were perceived to be increasing the number of sonographers trained each year, whilst training people in their first choice profession with skills developed specific to the sonographer role. Support for direct entry ultrasound training was limited to 51% of respondents who would advocate this form of ultrasound training if it led to qualified sonographers with the same skills as sonographers exiting from current CASE accredited programmes. PMID:27433263

  8. Use of 'non-medical' ultrasound imaging before mid-pregnancy in Copenhagen.

    PubMed

    Thorup, Tine J; Zingenberg, Helle

    2015-01-01

    We have investigated prospectively how many pregnant women purchase ultrasound imaging before week 20, why they purchase scans, and which professional skills and certifications women expect the person performing the scan to have. In addition, we wanted to investigate whether the women were aware of any professional authorization procedures. Women attending the second trimester malformation scan of the Danish Prenatal Screening Program (n = 645) filled in a questionnaire about their use of non-medical ultrasound scans. Of these women, 154 (24%) had bought ultrasound scans: 50% wanted to have the fetal health and development checked and 49% wanted to find out the gender of the fetus. In addition, 68% felt that they received an evaluation of the fetal health state and 58% believed that there was legislation demanding a professional authorization needed to perform ultrasound imaging. This study shows that there is a significant demand among pregnant women for commercial ultrasound imaging of their fetus for various reasons. Knowledge of certifications and requirements for legal authorization is, however, sparse. PMID:25252095

  9. Acoustic holography as a metrological tool for characterizing medical ultrasound sources and fields

    PubMed Central

    Sapozhnikov, Oleg A.; Tsysar, Sergey A.; Khokhlova, Vera A.; Kreider, Wayne

    2015-01-01

    Acoustic holography is a powerful technique for characterizing ultrasound sources and the fields they radiate, with the ability to quantify source vibrations and reduce the number of required measurements. These capabilities are increasingly appealing for meeting measurement standards in medical ultrasound; however, associated uncertainties have not been investigated systematically. Here errors associated with holographic representations of a linear, continuous-wave ultrasound field are studied. To facilitate the analysis, error metrics are defined explicitly, and a detailed description of a holography formulation based on the Rayleigh integral is provided. Errors are evaluated both for simulations of a typical therapeutic ultrasound source and for physical experiments with three different ultrasound sources. Simulated experiments explore sampling errors introduced by the use of a finite number of measurements, geometric uncertainties in the actual positions of acquired measurements, and uncertainties in the properties of the propagation medium. Results demonstrate the theoretical feasibility of keeping errors less than about 1%. Typical errors in physical experiments were somewhat larger, on the order of a few percent; comparison with simulations provides specific guidelines for improving the experimental implementation to reduce these errors. Overall, results suggest that holography can be implemented successfully as a metrological tool with small, quantifiable errors. PMID:26428789

  10. A perspective on high-frequency ultrasound for medical applications

    NASA Astrophysics Data System (ADS)

    Mamou, Jonathan; Aristizába, Orlando; Silverman, Ronald H.; Ketterling, Jeffrey A.

    2010-01-01

    High-frequency ultrasound (HFU, >15 MHz) is a rapidly developing field. HFU is currently used and investigated for ophthalmologic, dermatologic, intravascular, and small-animal imaging. HFU offers a non-invasive means to investigate tissue at the microscopic level with resolutions often better than 100 μm. However, fine resolution is only obtained over the limited depth-of-field (˜1 mm) of single-element spherically-focused transducers typically used for HFU applications. Another limitation is penetration depth because most biological tissues have large attenuation at high frequencies. In this study, two 5-element annular arrays with center frequencies of 17 and 34 MHz were fabricated and methods were developed to obtain images with increased penetration depth and depth-of-field. These methods were used in ophthalmologic and small-animal imaging studies. Improved blood sensitivity was obtained when a phantom mimicking a vitreous hemorrhage was imaged. Central-nervous systems of 12.5-day-old mouse embryos were imaged in utero and in three dimensions for the first time.

  11. Diagnostic value of endobronchial ultrasound-guided transbronchial needle aspiration in various lung diseases

    PubMed Central

    Ortakoylu, Mediha Gonenc; Iliaz, Sinem; Bahadir, Ayse; Aslan, Asuman; Iliaz, Raim; Ozgul, Mehmet Akif; Urer, Halide Nur

    2015-01-01

    Objective: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a new method for the diagnosis and staging of lung disease, and its use is increasing worldwide. It has been used as a means of diagnosing lung cancer in its initial stages, and there are data supporting its use for the diagnosis of benign lung disease. The aim of this study was to share our experience with EBUS-TBNA and discuss its diagnostic value. Methods: We retrospectively analyzed the results related to 159 patients who underwent EBUS-TBNA at our pulmonary medicine clinic between 2010 and 2013. We recorded the location and size of lymph nodes seen during EBUS. Lymph nodes that appeared to be affected on EBUS were sampled at least twice. We recorded the diagnostic results of EBUS-TBNA and (for cases in which EBUS-TBNA yielded an inconclusive diagnosis) the final diagnoses after further investigation and follow-up. Results: We evaluated 159 patients, of whom 89 (56%) were male and 70 (44%) were female. The mean age was 54.6 ± 14.2 years among the male patients and 51.9 ± 11.3 years among the female patients. Of the 159 patients evaluated, 115 (84%) were correctly diagnosed by EBUS. The diagnostic accuracy of EBUS-TBNA was 83% for benign granulomatous diseases and 77% for malignant diseases. Conclusions: The diagnostic value of EBUS-TBNA is also high for benign pathologies, such as sarcoidosis and tuberculosis. In patients with mediastinal disorders, the use of EBUS-TBNA should be encouraged, primarily because it markedly reduces the need for mediastinoscopy. PMID:26578131

  12. Using computer aided system to determine the maximum depth of visualization of B-Mode diagnostic ultrasound image

    NASA Astrophysics Data System (ADS)

    Maslebu, G.; Adi, K.; Suryono

    2016-03-01

    In the service unit of radiology, ultrasound modality is widely used because it has advantages over other modalities, such as relatively inexpensive, non-invasive, does not use ionizing radiation, and portable. Until now, the method for determining the depth visualization on quality control program is through the visual observation of ultrasound image on the monitor. The purpose of this study is to develop a computer-aided system to determine maximum depth of visualization. Data acquisition was done by using B-Mode Diagnostic Ultrasound machine and Multi-purpose Multi-tissue Ultrasound Phantom model 040GSE. Phantom was scanned at fixed frequency of 1,8 MHz, 2,2 MHz, 3,6 MHz and 5,0 MHz with a gain variation of 30 dB, 45 dB, and 60 dB. Global thresholding and Euclidean distance method were used to determine maximum visualization depth. From this study, it is proved that the visualization depth using computer aided provide deeper visualization than visual interpretation. The differences between expert verification and the result of image processing are <6%. Thus, computer aided system can be used for the purpose of quality control in determining maximum visualization depth of B-Mode diagnostic ultrasound image.

  13. The future of novel diagnostics in medical mycology.

    PubMed

    Teles, Fernando; Seixas, Jorge

    2015-04-01

    Several fungal diseases have become serious threats to human health and life, especially upon the advent of human immunodeficiency virus/AIDS epidemics and of other typical immunosuppressive conditions of modern life. Accordingly, the burden posed by these diseases and, concurrently, by intensive therapeutic regimens against these diseases has increased worldwide. Existing and available rapid tests for point-of-care diagnosis of important fungal diseases could enable the limitations of current laboratory methods for detection and identification of medically important fungi to be surpassed, both in low-income countries and for first-line diagnosis (screening) in richer countries. As with conventional diagnostic methods and devices, former immunodiagnostics have been challenged by molecular biology-based platforms, as a way to enhance the sensitivity and shorten the assay time, thus enabling early and more accurate diagnosis. Most of these tests have been developed in-house, without adequate validation and standardization. Another challenge has been the DNA extraction step, which is especially critical when dealing with fungi. In this paper, we have identified three major research trends in this field: (1) the application of newer biorecognition techniques, often applied in analytical chemistry; (2) the development of new materials with improved physico-chemical properties; and (3) novel bioanalytical platforms, allowing fully automated testing. Keeping up to date with the fast technological advances registered in this field, primarily at the proof-of-concept level, is essential for wise assessment of those that are likely to be more cost effective and, as already observed for bacterial and viral pathogens, may provide leverage to the current tepid developmental status of novel and improved diagnostics for medical mycology. PMID:25418735

  14. Novel x-ray optics for medical diagnostic techniques

    NASA Astrophysics Data System (ADS)

    Kuyumchyan, A.; Arvanian, V.; Kuyumchyan, D.; Aristov, V.; Shulakov, E.

    2009-08-01

    A new hard X - ray hologram with using crystal Fresnel zone plates (ZP) has been described. An image of Fourier hologram for hard X- ray is presented. X-ray phase contrast methods for medical diagnostics techniques are presented. We have developed an X-ray microscope, based on micro focus source which is capable of high resolution phasecontrast imaging and holograms. We propose a new imaging technique with the x-ray energy 8 keV. The method is expected to have wide applications in imaging of low absorbing samples such as biological and medical tissue. We used FIB to reproduction three dimension structures of damaged spinal cord of rat before and after combined treatment with NT3 and NR2D. PUBLISHER'S NOTE 12/16/09: This SPIE Proceedings paper has been updated with an erratum correcting several issues throughout the paper. The corrected paper was published in place of the earlier version on 9/1/2009. If you purchased the original version of the paper and no longer have access, please contact SPIE Digital Library Customer Service at CustomerService@SPIEDigitalLibrary.org for assistance.

  15. A new method for tracking organ motion on diagnostic ultrasound images

    SciTech Connect

    Kubota, Yoshiki Matsumura, Akihiko; Fukahori, Mai; Minohara, Shin-ichi; Yasuda, Shigeo; Nagahashi, Hiroshi

    2014-09-15

    Purpose: Respiratory-gated irradiation is effective in reducing the margins of a target in the case of abdominal organs, such as the liver, that change their position as a result of respiratory motion. However, existing technologies are incapable of directly measuring organ motion in real-time during radiation beam delivery. Hence, the authors proposed a novel quantitative organ motion tracking method involving the use of diagnostic ultrasound images; it is noninvasive and does not entail radiation exposure. In the present study, the authors have prospectively evaluated this proposed method. Methods: The method involved real-time processing of clinical ultrasound imaging data rather than organ monitoring; it comprised a three-dimensional ultrasound device, a respiratory sensing system, and two PCs for data storage and analysis. The study was designed to evaluate the effectiveness of the proposed method by tracking the gallbladder in one subject and a liver vein in another subject. To track a moving target organ, the method involved the control of a region of interest (ROI) that delineated the target. A tracking algorithm was used to control the ROI, and a large number of feature points and an error correction algorithm were used to achieve long-term tracking of the target. Tracking accuracy was assessed in terms of how well the ROI matched the center of the target. Results: The effectiveness of using a large number of feature points and the error correction algorithm in the proposed method was verified by comparing it with two simple tracking methods. The ROI could capture the center of the target for about 5 min in a cross-sectional image with changing position. Indeed, using the proposed method, it was possible to accurately track a target with a center deviation of 1.54 ± 0.9 mm. The computing time for one frame image using our proposed method was 8 ms. It is expected that it would be possible to track any soft-tissue organ or tumor with large deformations and

  16. An improved automatic time-of-flight picker for medical ultrasound tomography

    PubMed Central

    Li, Cuiping; Huang, Lianjie; Duric, Nebojsa; Zhang, Haijiang; Rowe, Charlotte

    2014-01-01

    Objective and motivation Time-of-flight (TOF) tomography used by a clinical ultrasound tomography device can efficiently and reliably produce sound–speed images of the breast for cancer diagnosis. Accurate picking of TOFs of transmitted ultrasound signals is extremely important to ensure high-resolution and high-quality ultrasound sound–speed tomograms. Since manually picking is time-consuming for large datasets, we developed an improved automatic TOF picker based on the Akaike information criterion (AIC), as described in this paper. Methods We make use of an approach termed multi-model inference (model averaging), based on the calculated AIC values, to improve the accuracy of TOF picks. By using multi-model inference, our picking method incorporates all the information near the TOF of ultrasound signals. Median filtering and reciprocal pair comparison are also incorporated in our AIC picker to effectively remove outliers. Results We validate our AIC picker using synthetic ultrasound waveforms, and demonstrate that our automatic TOF picker can accurately pick TOFs in the presence of random noise with absolute amplitudes up to 80% of the maximum absolute signal amplitude. We apply the new method to 1160 in vivo breast ultrasound waveforms, and compare the picked TOFs with manual picks and amplitude threshold picks. The mean value and standard deviation between our TOF picker and manual picking are 0.4 μs and 0.29 μs, while for amplitude threshold picker the values are 1.02 μs and 0.9 μs, respectively. Tomograms for in vivo breast data with high signal-to-noise ratio (SNR) (~25 dB) and low SNR (~18 dB) clearly demonstrate that our AIC picker is much less sensitive to the SNRs of the data, compared to the amplitude threshold picker. Discussion and conclusions The picking routine developed here is aimed at determining reliable quantitative values, necessary for adding diagnostic information to our clinical ultrasound tomography device – CURE. It has been

  17. A comprehensive evaluation of the 8-gauge vacuum-assisted Mammotome® system for ultrasound-guided diagnostic biopsy and selective excision of breast lesions

    PubMed Central

    Povoski, Stephen P; Jimenez, Rafael E

    2007-01-01

    Background Minimally invasive breast biopsy technology is now considered a standard of care for the diagnostic evaluation of suspicious breast lesions. The aim of the current study was to present a comprehensive evaluation of the 8-gauge vacuum-assisted Mammotome® system for ultrasound-guided diagnostic biopsy and selective excision of breast lesions. Methods A retrospective analysis was conducted of a series of 304 consecutive 8-gauge Mammotome® procedures that were performed under ultrasound guidance by a single surgeon from March 2004 to December 2006. Multiple variables, including patient demographics, characteristics of the breast lesion (based on ultrasound and mammography), procedural and histopathology variables, and interval follow-up variables (based on ultrasound and mammography), were evaluated. Results Among 304 procedures, 235 (77%) were performed with the presumption of complete excision of the ultrasound lesion during Mammotome® core acquisition, while 69 (23%) were performed with only partial excision of the ultrasound lesion during Mammotome® core acquisition (diagnostic tissue sampling only). 100% of all ultrasound lesions were accurately diagnosed, demonstrating no apparent false-negative results among the 256 patients that were compliant with follow-up at a median interval follow-up duration of 11 months (range 1 to 37). Likewise, 89% of all appropriately selected ultrasound lesions were completely excised, as demonstrated on interval follow-up ultrasound at a median time of 6 months (range, 3 to 16). There were no independent predictors of successful complete excision of any given appropriately selected ultrasound lesion by the ultrasound-guided 8-gauge Mammotome® biopsy technique. Conclusion The 8-gauge vacuum-assisted Mammotome® system is highly accurate for ultrasound-guided diagnostic biopsy of suspicious breast lesions and is highly successful for complete excision of appropriately selected presumed benign breast lesions. This

  18. Development of polymer 'chips' used in medical diagnostics

    SciTech Connect

    Brush, Zachary G; Schultz, Laura M; Vanness, Justin W; Farinholt, Kevin M; Sarles, Stephen; Leo, Donald

    2011-01-26

    In recent years, there has been growing interest in creating bio-inspired devices that feature artificial bilayer lipid membranes (BLM), or lipid bilayers. These membranes can be tailored to mimic the structure and transport properties of cellular walls and can be used to selectively transport ions and other species between aqueous volumes. One application of this research is the formation of a standardized BLM contained within a portable and disposable housing for use in medical diagnostics. This concept utilizes a flexible polymer 'chip' that has internal compartments for housing both an organic solvent and an aqueous solution, which contains phospholipid molecules, proteins, and specific analyte molecules. The formation of a BLM within the chip enables integration of the chip into an electronic reader to perform diagnostic measurements of the sample. A key element of the bilayer formation process requires a single aqueous volume to first be separated into multiple volumes such that it can then be reattached to form a bilayer at the interface. This process, called the regulated attachment method, relies on the geometry of the deformable 'chip' to separate and reattach the aqueous contents held inside by opening and closing an aperture that divides adjacent compartments through the application of mechanical force. The purpose of this research is to develop an optimized chip that provides a controllable method for initially separating the aqueous phase via dynamic excitation. This study focuses on two specific aspects: designing an efficient excitation method for separating the aqueous volume, and optimizing the geometry of the chip to decrease the required input energy and better target the location and duration of the separation. Finite Element (FE) models are used to optimize the chip geometry and to identify suitable excitation signals. A series of experimental studies are also presented to validate the FE models.

  19. Development of polymer 'chips' used in medical diagnostics

    SciTech Connect

    Brush, Zachary G; Schultz, Laura M; Vanness, Justin W; Farinholt, Kevin M; Sarles, Stephen; Leo, Donald

    2010-11-03

    In recent years, there has been growing interest in creating bio-inspired devices that feature artificial bilayer lipid membranes (BLM), or lipid bilayers. These membranes can be tailored to mimic the structure and transport properties of cellular walls and can be used to selectively transport ions and other species between aqueous volumes. One application of this research is the formation of a standardized BLM contained within a portable and disposable housing for use in medical diagnostics. This concept utilizes a flexible polymer 'chip' that has internal compartments for housing both an organic solvent and an aqueous solution, which contains phospholipid molecules, proteins, and specific analyte molecules. The formation of a BLM within the chip enables integration of the chip into an electronic reader to perform diagnostic measurements of the sample. A key element of the bilayer formation process requires a single aqueous volume to first be separated into multiple volumes such that it can then be reattached to form a bilayer at the interface. This process, called the regulated attachment method, relies on the geometry of the deformable 'chip' to separate and reattach the aqueous contents held inside by opening and closing an aperture that divides adjacent compartments through the application of mechanical force. The purpose of this research is to develop an optimized chip that provides a controllable method for initially separating the aqueous phase via dynamic excitation. This study focuses on two specific aspects: designing an efficient excitation method for separating the aqueous volume, and optimizing the geometry of the chip to decrease the required input energy and better target the location and duration of the separation. Finite Element (FE) models are used to optimize the chip geometry and to identify suitable excitation signals. A series of experimental studies are also presented to validate the FE models.

  20. Preoperative Ultrasound Guided Fine Needle Aspiration Cytology of Ovarian Lesions- Is It a Rapid and Effective Diagnostic Modality?

    PubMed Central

    Datta, Saikat; Chaudhuri, Snehamay; Paul, Prabir Chandra; Khandakar, Binny; Mandal, Sonali

    2016-01-01

    Introduction The deep seated ovarian lesions unapproachable by unguided aspiration cytology were easily done under ultrasound guidance. It gave a before hand cytological diagnosis of the lesion to the surgeon determining the modality of treatment for the patient. Aim To find the diagnostic accuracy of the method of ultrasound guided cytological assessment of ovarian lesion. Materials and Methods The study was conducted as a prospective observational study over a period of one year, in hospital setting, where ultrasound guided fine needle aspiration had been used to aspirate ovarian lesions, giving a rapid cytological diagnosis. In 43 sample cases, aspiration of fluid done from ovarian lesions were followed by cyto-centrifugation and staining by May-Grunwald-Giemsa (MGG) and Papanicolaou (Pap) stain providing a cytological opinion regarding benign/malignant nature of the lesion and further categorization. Later the cytological diagnosis was compared with final histopathological diagnosis, taking it as a gold standard. Results The overall sensitivity, specificity, and diagnostic accuracy of ultrasound guided aspiration and cytological analysis were high, 96%, 76.92% and 89.47% respectively as calculated by comparing the cytological diagnosis with histological diagnosis, taking it as gold standard. Conclusion This method has evolved as a highly sensitive, rapid, simple and effective modality for screening and as well as accurate preoperative diagnosis of ovarian lesions. PMID:27134878

  1. Use of modulated excitation signals in medical ultrasound. Part II: Design and performance for medical imaging applications.

    PubMed

    Misaridis, Thanassis; Jensen, Jørgen Arendt

    2005-02-01

    In the first paper, the superiority of linear FM signals was shown in terms of signal-to-noise ratio and robustness to tissue attenuation. This second paper in the series of three papers on the application of coded excitation signals in medical ultrasound presents design methods of linear FM signals and mismatched filters, in order to meet the higher demands on resolution in ultrasound imaging. It is shown that for the small time-bandwidth (TB) products available in ultrasound, the rectangular spectrum approximation is not valid, which reduces the effectiveness of weighting. Additionally, the distant range sidelobes are associated with the ripples of the spectrum amplitude and, thus, cannot be removed by weighting. Ripple reduction is achieved through amplitude or phase predistortion of the transmitted signals. Mismatched filters are designed to efficiently use the available bandwidth and at the same time to be insensitive to the transducer's impulse response. With these techniques, temporal sidelobes are kept below 60 to 100 dB, image contrast is improved by reducing the energy within the sidelobe region, and axial resolution is preserved. The method is evaluated first for resolution performance and axial sidelobes through simulations with the program Field II. A coded excitation ultrasound imaging system based on a commercial scanner and a 4 MHz probe driven by coded sequences is presented and used for the clinical evaluation of the coded excitation/compression scheme. The clinical images show a significant improvement in penetration depth and contrast, while they preserve both axial and lateral resolution. At the maximum acquisition depth of 15 cm, there is an improvement of more than 10 dB in the signal-to-noise ratio of the images. The paper also presents acquired images, using complementary Golay codes, that show the deleterious effects of attenuation on binary codes when processed with a matched filter, also confirmed by presented simulated images. PMID

  2. Diagnostic value of ultrasound in calcium pyrophosphate deposition disease: a systematic review and meta-analysis

    PubMed Central

    Gamon, Etienne; Combe, Bernard; Barnetche, Thomas; Mouterde, Gaël

    2015-01-01

    Objective A systematic review and meta-analysis of data from cohort studies to analyse the diagnostic performances (ie, sensitivity and specificity) of ultrasound (US) for diagnosis of calcium pyrophosphate deposition (CPPD) disease with microscopic crystal detection used as a gold standard. Methods We performed a systematic review of articles published up to December 2014 using EMBASE, MEDLINE and Cochrane databases and abstracts from the past two EULAR and ACR annual meetings. Only studies reporting the performance of US for diagnosis of CPPD disease were selected. A meta-analysis involved the inverse variance method to evaluate global sensitivity and specificity of US. Statistical heterogeneity was assessed by the Cochran Q-test and I2 values. Results The search resulted in 85 articles and 11 abstracts; 17 and 4, respectively, were selected for the systematic review. A total of 262 patients with CPPD disease and 335 controls from 4 original articles and 4 abstracts were included in the meta-analysis. The US diagnostic patterns most frequently recorded were thin hyperechoic bands in the hyaline cartilage (8 articles); hyperechoic spots in fibrous cartilage or in tendons (7 articles); and homogeneous hyperechoic nodules localised in bursa or articular recesses (4 articles). The meta-analysis revealed a heterogeneity of the data, with a sensitivity of 87.9% (95% CI 80.9% to 94.9%) and specificity of 91.5% (95% CI 85.5% to 97.5%) using a random model. Conclusions This meta-analysis confirmed that US has high sensitivity and specificity for the diagnosis of CPPD and may be a promising tool for the diagnosis and management of CPPD. PMID:26535143

  3. Ultrasound Elastography and MR Elastography for Assessing Liver Fibrosis: Part 2, Diagnostic Performance, Confounders, and Future Directions

    PubMed Central

    Tang, An; Cloutier, Guy; Szeverenyi, Nikolaus M.; Sirlin, Claude B.

    2016-01-01

    OBJECTIVE The purpose of the article is to review the diagnostic performance of ultrasound and MR elastography techniques for detection and staging of liver fibrosis, the main current clinical applications of elastography in the abdomen. CONCLUSION Technical and instrument-related factors and biologic and patient-related factors may constitute potential confounders of stiffness measurements for assessment of liver fibrosis. Future developments may expand the scope of elastography for monitoring liver fibrosis and predict complications of chronic liver disease. PMID:25905762

  4. Safety Assurance in Obstetrical Ultrasound

    PubMed Central

    Miller, Douglas L

    2008-01-01

    Safety assurance for diagnostic ultrasound in obstetrics began with a tacit assumption of safety allowed by a federal law enacted in 1976 for then-existing medical ultrasound equipment. The implementation of the 510(k) pre-market approval process for diagnostic ultrasound resulted in the establishment of guideline upper limits for several examination categories in 1985. The obstetrical category has undergone substantial evolution from initial limits (I. e., 46 mW/cm2 spatial peak temporal average (SPTA) intensity) set in 1985. Thermal and mechanical exposure indices, which are displayed on-screen according to an Output Display Standard (ODS), were developed for safety assurance with relaxed upper limits. In 1992, with the adoption of the ODS, the allowable output for obstetrical ultrasound was increased both in terms of the average exposure (e. g. to a possible 720 mW/cm2 SPTA intensity) and of the peak exposure (via the Mechanical Index). There has been little or no subsequent research with the modern obstetrical ultrasound machines to systematically assess potential risks to the fetus using either relevant animal models of obstetrical exposure or human epidemiology studies. The assurance of safety for obstetrical ultrasound therefore is supported by three ongoing means: (I) review of a substantial but uncoordinated bioeffect research literature, (ii) the theoretical evaluation of diagnostic ultrasound exposure in terms of thermal and nonthermal mechanisms for bioeffects, and (iii) the skill and knowledge of professional sonographers. At this time, there is no specific reason to suspect that there is any significant health risk to the fetus or mother from exposure to diagnostic ultrasound in obstetrics. This assurance of safety supports the prudent use of diagnostic ultrasound in obstetrics by trained professionals for any medically indicated examination. PMID:18450141

  5. Safety assurance in obstetrical ultrasound.

    PubMed

    Miller, Douglas L

    2008-04-01

    Safety assurance for diagnostic ultrasound in obstetrics began with a tacit assumption of safety allowed by a federal law enacted in 1976 for then-existing medical ultrasound equipment. The implementation of the 510(k) pre-market-approval process for diagnostic ultrasound resulted in the establishment of guideline upper limits for several examination categories in 1985. The obstetrical category has undergone substantial evolution from initial limits (ie, 46 mW/cm2 spatial peak temporal average [SPTA] intensity) set in 1985. Thermal and mechanical exposure indices, which are displayed onscreen according to an Output Display Standard, were developed for safety assurance with relaxed upper limits. In 1992, with the adoption of the Output Display Standard, the allowable output for obstetrical ultrasound was increased in terms of both the average exposure (eg, to a possible 720 mW/cm2 SPTA intensity) and the peak exposure (via the Mechanical Index). There has been little or no subsequent research with the modern obstetrical ultrasound machines to systematically assess potential risks to the fetus using either relevant animal models of obstetrical exposure or human epidemiology studies. The assurance of safety for obstetrical ultrasound therefore is supported by three ongoing means: (1) review of a substantial but uncoordinated bioeffect research literature; (2) the theoretical evaluation of diagnostic ultrasound exposure in terms of thermal and nonthermal mechanisms for bioeffects; and (3) the skill and knowledge of professional sonographers. At this time, there is no specific reason to suspect that there is any significant health risk to the fetus or mother from exposure to diagnostic ultrasound in obstetrics. This assurance of safety supports the prudent use of diagnostic ultrasound in obstetrics by trained professionals for any medically indicated examination. PMID:18450141

  6. Efforts to improve the diagnostic accuracy of endoscopic ultrasound-guided fine-needle aspiration for pancreatic tumors

    PubMed Central

    Yamabe, Akane; Irisawa, Atsushi; Bhutani, Manoop S.; Shibukawa, Goro; Fujisawa, Mariko; Sato, Ai; Yoshida, Yoshitsugu; Arakawa, Noriyuki; Ikeda, Tsunehiko; Igarashi, Ryo; Maki, Takumi; Yamamoto, Shogo

    2016-01-01

    Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is widely used to obtain a definitive diagnosis of pancreatic tumors. Good results have been reported for its diagnostic accuracy, with high sensitivity and specificity of around 90%; however, technological developments and adaptations to improve it still further are currently underway. The endosonographic technique can be improved when several tips and tricks useful to overcome challenges of EUS-FNA are known. This review provides various techniques and equipment for improvement in the diagnostic accuracy in EUS-FNA. PMID:27503153

  7. Diagnostic value of contrast-enhanced ultrasound in papillary thyroid microcarcinoma

    PubMed Central

    CHEN, HONG YAN; LIU, WEI YAN; ZHU, HUI; JIANG, DAO WEN; WANG, DONG HUA; CHEN, YONGQI; LI, WEIHUA; PAN, GAOFENG

    2016-01-01

    The aim of the present study was to explore the value and characteristics of contrast-enhanced ultrasound (CEUS) in the diagnosis of papillary thyroid microcarcinoma (PTMC). By analyzing CEUS information of 130 nodules obtained from 106 patients with PTMC, who had been diagnosed by surgery and pathological analysis, CEUS characteristics of PTMC nodules were concluded. Based on the results, the PTMC nodules were divided into three groups as follows: 32 nodules (24.62%) were found to be enhanced earlier than the surrounding normal thyroid tissue, 95 nodules (73.08%) were enhanced at the same time as the normal thyroid tissue and 3 nodules (2.30%) were enhanced later than the normal thyroid tissue. The results also demonstrated that the peak enhancement intensity of the 130 nodules was lower compared with the irregular intensity of the normal parenchyma in corresponding thyroids, and that PTMC enhancement washed out faster than in normal thyroid parenchyma. In conclusion, the PTMC characteristics that CEUS can detect may improve the diagnostic accuracy and provide valuable information for the treatment of the disease. PMID:27168773

  8. Medical diagnostics with mobile devices: Comparison of intrinsic and extrinsic sensing.

    PubMed

    Kwon, L; Long, K D; Wan, Y; Yu, H; Cunningham, B T

    2016-01-01

    We review the recent development of mobile detection instruments used for medical diagnostics, and consider the relative advantages of approaches that utilize the internal sensing capabilities of commercially available mobile communication devices (such as smartphones and tablet computers) compared to those that utilize a custom external sensor module. In this review, we focus specifically upon mobile medical diagnostic platforms that are being developed to serve the need in global health, personalized medicine, and point-of-care diagnostics. PMID:26952640

  9. Pancreatic cystic lesions: How endoscopic ultrasound morphology and endoscopic ultrasound fine needle aspiration help unlock the diagnostic puzzle

    PubMed Central

    Barresi, Luca; Tarantino, Ilaria; Granata, Antonino; Curcio, Gabriele; Traina, Mario

    2012-01-01

    Cystic lesions of the pancreas are being diagnosed with increasing frequency, covering a vast spectrum from benign to malignant and invasive lesions. Numerous investigations can be done to discriminate between benign and non-evolutive lesions from those that require surgery. At the moment, there is no single test that will allow a correct diagnosis in all cases. Endoscopic ultrasound (EUS) morphology, cyst fluid analysis and cytohistology with EUS-guided fine needle aspiration can aid in this difficult diagnosis. PMID:22720127

  10. Despeckling of medical ultrasound images using data and rate adaptive lossy compression.

    PubMed

    Gupta, Nikhil; Swamy, M N S; Plotkin, Eugene

    2005-06-01

    A novel technique for despeckling the medical ultrasound images using lossy compression is presented. The logarithm of the input image is first transformed to the multiscale wavelet domain. It is then shown that the subband coefficients of the log-transformed ultrasound image can be successfully modeled using the generalized Laplacian distribution. Based on this modeling, a simple adaptation of the zero-zone and reconstruction levels of the uniform threshold quantizer is proposed in order to achieve simultaneous despeckling and quantization. This adaptation is based on: (1) an estimate of the corrupting speckle noise level in the image; (2) the estimated statistics of the noise-free subband coefficients; and (3) the required compression rate. The Laplacian distribution is considered as a special case of the generalized Laplacian distribution and its efficacy is demonstrated for the problem under consideration. Context-based classification is also applied to the noisy coefficients to enhance the performance of the subband coder. Simulation results using a contrast detail phantom image and several real ultrasound images are presented. To validate the performance of the proposed scheme, comparison with two two-stage schemes, wherein the speckled image is first filtered and then compressed using the state-of-the-art JPEG2000 encoder, is presented. Experimental results show that the proposed scheme works better, both in terms of the signal to noise ratio and the visual quality. PMID:15957598

  11. Cancer among medical diagnostic x-ray workers in China

    SciTech Connect

    Wang, J.X.; Boice, J.D. Jr.; Li, B.X.; Zhang, J.Y.; Fraumeni, J.F. Jr.

    1988-05-04

    Cancer incidence among 27,011 diagnostic x-ray workers was compared to that of 25,782 other medical specialists employed between 1950 and 1980 in China. X-ray workers had a 50% higher risk of developing cancer than the other specialists (relative risk (RR) = 1.5; 95% CI = 1.3-1.7). Leukemia was strongly linked to radiation work (RR = 3.5, n = 30). Cancers of the breast (RR = 1.4, n = 11), thyroid (RR = 2.1, n = 7), and skin (RR = 1.5, n = 6) were increased among x-ray workers employed for 10 or more years. High risks of cancers of the esophagus (RR = 3.5, n = 15) and liver (RR = 2.4, n = 48) were not consistent with a radiation effect since risk did not vary by duration of employment. This finding suggested that some differences might exist between groups of hospital workers in social class, alcohol intake, dietary habits, and other risk factors. No excess lung cancer (RR = 0.9, n = 22) or multiple myeloma (n = 0) was observed. Significant excesses of leukemia and cancers of the breast and thyroid occurred among x-ray workers first employed prior to 1960 when radiation exposures in China were high. In fact, it was not uncommon for employees to be given time off from x-ray work because their wbc count was severely depressed. These data indicated that repeated exposure to x-rays over many years can increase the risk of leukemia and several other tumors but apparently not that of lung cancer.

  12. Diagnostic value of preoperative axillary lymph node ultrasound assessment in patients with breast cancer qualified for sentinel lymph node biopsy

    PubMed Central

    Nowak, Adam; Wiśniewska, Magdalena; Wiśniewski, Michał; Zegarski, Wojciech

    2015-01-01

    Introduction Sentinel lymph node biopsy (SLNB) is a standard procedure in the therapeutic management of patients with non-advanced breast cancer. Aim To analyse the utility of ultrasound scan (USS) examination in the process of patient qualification for SLNB and to estimate the optimal time to perform USS in the clinical preoperational assessment of axillary lymph nodes. Material and methods A prospective analysis of 702 patients with invasive breast cancer treated with SLNB between 7.03.2012 and 27.05.2013 was performed. The patients were divided into three groups: I (USS < 8 weeks before SLNB), II (USS > 8 weeks before SLNB and another one on the day before SLNB) and III (USS > 8 weeks before SLNB without perioperative USS). In these patients the percentage of metastases in the sentinel lymph node and the clinical factors influencing the diagnostic value of preoperative ultrasound scan were assessed. Results Metastatic lesions in sentinel lymph nodes were found in 154 (21.9%) patients. The highest percentage of metastases was noted in patients operated on in the second and third month from the beginning of preoperative diagnostics. None of the factors tested (size of the original tumour, histological malignancy grading, kind of preoperative diagnostics, Ki-67 value, biological type of the tumour, age) had a statistically significant influence on the diagnostic value of perioperative USS examination in the analysed time span. Conclusions The lowest percentage of metastases in the sentinel lymph node was noted in the patients qualified for SLNB who had the ultrasound performed directly before the surgical procedure (not more than 4 weeks before the surgery). PMID:26240616

  13. Medical physics: some recollections in diagnostic X-ray imaging and therapeutic radiology.

    PubMed

    Gray, J E; Orton, C G

    2000-12-01

    Medical physics has changed dramatically since 1895. There was a period of slow evolutionary change during the first 70 years after Roentgen's discovery of x rays. With the advent of the computer, however, both diagnostic and therapeutic radiology have undergone rapid growth and changes. Technologic advances such as computed tomography and magnetic resonance imaging in diagnostic imaging and three-dimensional treatment planning systems, stereotactic radiosurgery, and intensity modulated radiation therapy in radiation oncology have resulted in substantial changes in medical physics. These advances have improved diagnostic imaging and radiation therapy while expanding the need for better educated and experienced medical physics staff. PMID:11110920

  14. The delay multiply and sum beamforming algorithm in ultrasound B-mode medical imaging.

    PubMed

    Matrone, Giulia; Savoia, Alessandro Stuart; Caliano, Giosue; Magenes, Giovanni

    2015-04-01

    Most of ultrasound medical imaging systems currently on the market implement standard Delay and Sum (DAS) beamforming to form B-mode images. However, image resolution and contrast achievable with DAS are limited by the aperture size and by the operating frequency. For this reason, different beamformers have been presented in the literature that are mainly based on adaptive algorithms, which allow achieving higher performance at the cost of an increased computational complexity. In this paper, we propose the use of an alternative nonlinear beamforming algorithm for medical ultrasound imaging, which is called Delay Multiply and Sum (DMAS) and that was originally conceived for a RADAR microwave system for breast cancer detection. We modify the DMAS beamformer and test its performance on both simulated and experimentally collected linear-scan data, by comparing the Point Spread Functions, beampatterns, synthetic phantom and in vivo carotid artery images obtained with standard DAS and with the proposed algorithm. Results show that the DMAS beamformer outperforms DAS in both simulated and experimental trials and that the main improvement brought about by this new method is a significantly higher contrast resolution (i.e., narrower main lobe and lower side lobes), which turns out into an increased dynamic range and better quality of B-mode images. PMID:25420256

  15. Spatially adaptive Bayesian wavelet thresholding for speckle removal in medical ultrasound images

    NASA Astrophysics Data System (ADS)

    Hou, Jianhua; Xiong, Chengyi; Chen, Shaoping; He, Xiang

    2007-12-01

    In this paper, a novel spatially adaptive wavelet thresholding method based on Bayesian maximum a posteriori (MAP) criterion is proposed for speckle removal in medical ultrasound (US) images. The method firstly performs logarithmical transform to original speckled ultrasound image, followed by redundant wavelet transform. The proposed method uses the Rayleigh distribution for speckle wavelet coefficients and Laplacian distribution for modeling the statistics of wavelet coefficients due to signal. A Bayesian estimator with analytical formula is derived from MAP estimation, and the resulting formula is proven to be equivalent to soft thresholding in nature which makes the algorithm very simple. In order to exploit the correlation among wavelet coefficients, the parameters of Laplacian model are assumed to be spatially correlated and can be computed from the coefficients in a neighboring window, thus making our method spatially adaptive in wavelet domain. Theoretical analysis and simulation experiment results show that this proposed method can effectively suppress speckle noise in medical US images while preserving as much as possible important signal features and details.

  16. Detection of increased intracranial pressure by ultrasound.

    PubMed

    Hightower, Stephanie; Chin, Eric J; Heiner, Jason D

    2012-01-01

    Increases in intracranial pressure (ICP) may damage the brain by compression of its structures or restriction of its blood flow, and medical providers my encounter elevated ICP in conventional and non-conventional medical settings. Early identification of elevated ICP is critical to ensuring timely and appropriate management. However, few diagnostic methods are available for detecting increased ICP in an acutely ill patient, which can be performed quickly and noninvasively at the bedside. The optic nerve sheath is a continuation of the dura mater of the central nervous system and can be viewed by ocular ultrasound. Pressure changes within the intracranial cavity affect the diameter of the optic nerve sheath. Data acquired from multiple clinical settings suggest that millimetric increases in the optic nerve sheath diameter detected via ocular ultrasound correlate with increasing levels of ICP. In this review, we discuss the use of ocular ultrasound to evaluate for the presence of elevated ICP via assessment of optic nerve sheath diameter, and describe critical aspects of this valuable diagnostic procedure. Ultrasound is increasingly becoming a medical fixture in the modern battlefield where other diagnostic modalities can be unavailable or impractical to employ. As Special Forces and other austere medical providers become increasingly familiar with ultrasound, ocular ultrasound for the assessment of increased intracranial pressure may help optimize their ability to provide the most effective medical management for their patients. PMID:23032316

  17. Eigenspace-Based Generalized Sidelobe Canceler Beamforming Applied to Medical Ultrasound Imaging.

    PubMed

    Li, Jiake; Chen, Xiaodong; Wang, Yi; Li, Wei; Yu, Daoyin

    2016-01-01

    The use of a generalized sidelobe canceler (GSC) can significantly improve the lateral resolution of medical ultrasound systems, but the contrast improvement isn't satisfactory. Thus a new Eigenspace-based generalized sidelobe canceler (EBGSC) approach is proposed for medical ultrasound imaging, which can improve both the lateral resolution and contrast of the system. The weight vector of the EBGSC is obtained by projecting the GSC weight vector onto a vector subspace constructed from the eigenstructure of the covariance matrix, and using the new weight vector instead of the GSC ones leads to reduced sidelobe level and improved contrast. Simulated and experimental data are used to evaluate the performance of the proposed method. The Field II software is applied to obtain the simulated echo data of scattering points and circular cysts. Imaging of scattering points show that EBGSC has the same full width at half maximum (FWHM) as GSC, while the lateral resolution improves by 35.3% and 52.7% compared with synthetic aperture (SA) and delay-and-sum (DS), respectively. Compared with GSC, SA and DS, EBGSC improves the peak sidelobe level (PSL) by 23.55, 33.11 and 50.38 dB, respectively. Also the cyst contrast increase by EBGSC was calculated as 16.77, 12.43 and 26.73 dB, when compared with GSC, SA and DS, respectively. Finally, an experiment is conducted on the basis of the complete echo data collected by a medical ultrasonic imaging system. Results show that the proposed method can produce better lateral resolution and contrast than non-adaptive beamformers. PMID:27483272

  18. Ultrasound-guided biopsy as a diagnostic aid in three horses with a cranial mediastinal lymphosarcoma.

    PubMed

    De Clercq, D; van Loon, G; Lefère, L; Deprez, P

    2004-06-01

    An ultrasound examination of the thorax of three horses which were performing poorly or had mild signs of colic showed that they had a cranial mediastinal mass and a pleural effusion. A cytological examination of the pleural fluid showed that it did not contain neoplastic cells. A histological examination of an ultrasound-guided core biopsy of the cranial mediastinal mass showed that in each of the three horses it was a lymphosarcoma. PMID:15214516

  19. Goal-Directed Ultrasound for the Diagnosis of Long-Bone Fractures by Crew Medical Officer Analogs

    NASA Technical Reports Server (NTRS)

    Marshburn, Thomas H.; Legome, Eric; Li, James; Melton, Shannon; Sargsyan, Ashot; Noble, Vickie; Sims, Carrie; Thomsen, Todd; Peralta, Ruben; Briggs, Sue

    2002-01-01

    Current construction activities on-board the International space Station (ISS) may increase fracture incidence in space, and ultrasound (US) is the only tm-board diagnostic imaging capability. The clinical utility of US in identifying long-bone fractures is un1aowe, particularly using non-radiologist operators. We sought to determine the accuracy of US in identifying fractures of the humerus and femur, as performed by emergency medicine physicians and surgeons with minimal experience in ultrasound image acquisition and interpretation, after a standardized taming session.

  20. Implementation of a versatile research data acquisition system using a commercially available medical ultrasound scanner.

    PubMed

    Hemmsen, Martin Christian; Nikolov, Svetoslav Ivanov; Pedersen, Mads Møller; Pihl, Michael Johannes; Enevoldsen, Marie Sand; Hansen, Jens Munk; Jensen, Jørgen Arendt

    2012-07-01

    This paper describes the design and implementation of a versatile, open-architecture research data acquisition system using a commercially available medical ultrasound scanner. The open architecture will allow researchers and clinicians to rapidly develop applications and move them relatively easy to the clinic. The system consists of a standard PC equipped with a camera link and an ultrasound scanner equipped with a research interface. The ultrasound scanner is an easy-to-use imaging device that is capable of generating high-quality images. In addition to supporting the acquisition of multiple data types, such as B-mode, M-mode, pulsed Doppler, and color flow imaging, the machine provides users with full control over imaging parameters such as transmit level, excitation waveform, beam angle, and focal depth. Beamformed RF data can be acquired from regions of interest throughout the image plane and stored to a file with a simple button press. For clinical trials and investigational purposes, when an identical image plane is desired for both an experimental and a reference data set, interleaved data can be captured. This form of data acquisition allows switching between multiple setups while maintaining identical transducer, scanner, region of interest, and recording time. Data acquisition is controlled through a graphical user interface running on the PC. This program implements an interface for third-party software to interact with the application. A software development toolkit is developed to give researchers and clinicians the ability to utilize third-party software for data analysis and flexible manipulation of control parameters. Because of the advantages of speed of acquisition and clinical benefit, research projects have successfully used the system to test and implement their customized solutions for different applications. Three examples of system use are presented in this paper: evaluation of synthetic aperture sequential beamformation, transverse

  1. A sequential decision-theoretic model for medical diagnostic system.

    PubMed

    Li, Aiping; Jin, Songchang; Zhang, Lumin; Jia, Yan

    2015-01-01

    Although diagnostic expert systems using a knowledge base which models decision-making of traditional experts can provide important information to non-experts, they tend to duplicate the errors made by experts. Decision-Theoretic Model (DTM) is therefore very useful in expert system since they prevent experts from incorrect reasoning under uncertainty. For the diagnostic expert system, corresponding DTM and arithmetic are studied and a sequential diagnostic decision-theoretic model based on Bayesian Network is given. In the model, the alternative features are categorized into two classes (including diseases features and test features), then an arithmetic for prior of test is provided. The different features affect other features weights are also discussed. Bayesian Network is adopted to solve uncertainty presentation and propagation. The model can help knowledge engineers model the knowledge involved in sequential diagnosis and decide evidence alternative priority. A practical example of the models is also presented: at any time of the diagnostic process the expert is provided with a dynamically updated list of suggested tests in order to support him in the decision-making problem about which test to execute next. The results show it is better than the traditional diagnostic model which is based on experience. PMID:26410326

  2. Diagnostic reference levels for medical exposure of patients: ICRP guidance and related ICRU quantities.

    PubMed

    Rosenstein, Marvin

    2008-11-01

    In Publication 60 of the International Commission on Radiological Protection reference levels were described as values of measured quantities at which some specified action or decision should be taken. One particular form of reference level, the diagnostic reference level, applies specifically to medical exposure of patients. The objective of a diagnostic reference level is to help avoid radiation dose to the patient that does not contribute to the clinical purpose of a medical imaging task. This is accomplished by comparison between the numerical value of the diagnostic reference level and the mean or other appropriate value observed in practice for a suitable reference group of patients or a suitable reference phantom. A diagnostic reference level is not applied to individual patients. Diagnostic reference levels have no direct linkage to the numerical values for dose limits or dose constraints, and it is inappropriate to use them for regulatory or commercial purposes. Diagnostic reference levels should be selected by professional medical bodies (often in conjunction with health and radiation protection authorities) and their values may be specific to a country or region. A diagnostic reference level can be used: (1) to improve a regional, national or local distribution of observed results for a general medical imaging task, by reducing the frequency of unjustified high or low values; (2) to promote attainment of a narrower range of values that represent good practice for a more specific medical imaging task; or (3) to promote attainment of an optimum range of values for a specified medical imaging protocol. Authorized bodies are encouraged to set diagnostic reference levels that best meet their specific needs and that are consistent for the regional, national or local area to which they apply. Report 74 of the International Commission on Radiation Units and Measurements includes a commentary regarding quantities useful in establishing diagnostic reference levels

  3. Temporal and spatial detection of HIFU-induced inertial and hot-vapor cavitation with a diagnostic ultrasound system.

    PubMed

    Farny, Caleb H; Holt, R Glynn; Roy, Ronald A

    2009-04-01

    The onset and presence of inertial cavitation and near-boiling temperatures in high-intensity focused ultrasound (HIFU) therapy have been identified as important indicators of energy deposition for therapy guidance. Passive cavitation detection is commonly used to detect bubble emissions, where a fixed-focus single-element acoustic transducer is typically used as a passive cavitation detector (PCD). This technique is suboptimal for clinical applications, because most PCD transducers are tightly focused and afford limited spatial coverage of the HIFU focal region. A Terason 2000 Ultrasound System was used as a PCD array to expand the spatial detection region for cavitation by operating in passive mode, obtaining the radiofrequency signals corresponding to each scan line and filtering the contribution from scattering of the HIFU signal harmonics. This approach allows for spatially resolved detection of both inertial and stable cavitation throughout the focal region. Measurements with the PCD array during sonication with a 1.1-MHz HIFU source in tissue phantoms were compared with single-element PCD and thermocouple sensing. Stable cavitation signals at the harmonics and superharmonics increased in a threshold fashion for temperatures >90 degrees C, an effect attributed to high vapor pressure in the cavities. Incorporation of these detection techniques in a diagnostic ultrasound platform could result in a powerful tool for improving HIFU guidance and treatment. PMID:19110368

  4. Examining Shifts in Medical Students' Microanalytic Motivation Beliefs and Regulatory Processes during a Diagnostic Reasoning Task

    ERIC Educational Resources Information Center

    Cleary, Timothy J.; Dong, Ting; Artino, Anthony R., Jr.

    2015-01-01

    This study examined within-group shifts in the motivation beliefs and regulatory processes of second-year medical students as they engaged in a diagnostic reasoning activity. Using a contextualized assessment methodology called self-regulated learning microanalysis, the authors found that the 71 medical student participants showed statistically…

  5. Diagnostic Yield of Medical Thoracoscopy in Undiagnosed Pleural Effusion

    PubMed Central

    Kiani, Arda; Karimi, Mahmoud; Samadi, Katayoun; Sheikhy, Kambiz; Farzanegan, Behrooz; Pour Abdollah, Mihan; Jamaati, Hamidreza; Jabardarjani, Hamid Reza; Masjedi, Mohammad Reza

    2015-01-01

    Background: One of the most common indications for pleuroscopy is undiagnosed pleural effusion, which comprises about 25% of all cases of pleural effusions, which remain undiagnosed despite primary tests. Pleuroscopy was performed for the first time in Iran in Masih Daneshvari hospital located in Tehran. The aim of this study was to assess the diagnostic yield of pleuroscopy performed in this center in Iran. Materials and Methods: Three-hundred patients with undiagnosed pleural effusions were enrolled in this study. For all patients, primary tests including pleural effusion analysis, cytology and closed pleural biopsy (if needed) were conducted and all of them were inconclusive. The semirigid thoracoscopy (pleuroscopy) was performed for all patients for diagnostic purposes. Results: Eighty-seven percent of the peluroscopies were diagnostic and 67% of them were diagnosed as malignancy while the rest were diagnosed as tuberculosis. Only 11 patients developed minor complications. Conclusion: In conclusion, pleuroscopy is a safe procedure when performed by a skilled and experienced practitioner; it has a high diagnostic yield and results in only minor complications. PMID:27114723

  6. In vivo demonstration of ultrasound power delivery to charge implanted medical devices via acute and survival porcine studies.

    PubMed

    Radziemski, Leon; Makin, Inder Raj S

    2016-01-01

    Animal studies are an important step in proving the utility and safety of an ultrasound based implanted battery recharging system. To this end an Ultrasound Electrical Recharging System (USER™) was developed and tested. Experiments in vitro demonstrated power deliveries at the battery of up to 600 mW through 10-15 mm of tissue, 50 mW of power available at tissue depths of up to 50 mm, and the feasibility of using transducers bonded to titanium as used in medical implants. Acute in vivo studies in a porcine model were used to test reliability of power delivery, temperature excursions, and cooling techniques. The culminating five-week survival study involved repeated battery charging, a total of 10.5h of ultrasound exposure of the intervening living tissue, with an average RF input to electrical charging efficiency of 20%. This study was potentially the first long term cumulative living-tissue exposure using transcutaneous ultrasound power transmission to an implanted receiver in situ. Histology of the exposed tissue showed changes attributable primarily due to surgical implantation of the prototype device, and no damage due to the ultrasound exposure. The in vivo results are indicative of the potential safe delivery of ultrasound energy for a defined set of source conditions for charging batteries within implants. PMID:26243566

  7. Do we need a critical care ultrasound certification program? Implications from an Australian medical-legal perspective.

    PubMed

    Huang, Stephen J; McLean, Anthony S

    2010-01-01

    Medical practitioners have a duty to maintain a certain standard of care in providing their services. With critical care ultrasound gaining popularity in the ICU, it is envisaged that more intensivists will use the tool in managing their patients. Ultrasound, especially echocardiography, can be an 'easy to learn, difficult to manage' skill, and the competency in performing the procedure varies greatly. In view of this, several recommendations for competency statements have been published in recent years to advocate the need for a unified approach to training and certification. In this paper, we take a slightly different perspective, from an Australian medical-legal viewpoint, to argue for the need to implement a critical care ultrasound certification program. We examine various issues that can potentially lead to a breach of the standard of care, hence exposing the practitioners and/or the healthcare institutions to lawsuits in professional negligence or breach of contract. These issues, among others, include the failure to use ultrasound in appropriate situations, the failure of hospitals to ensure practitioners are properly trained in the skills, the failure of practitioners to perform an ultrasound study that is of a reasonable standard, and the failure of practitioners to keep themselves abreast of the latest developments in treatment and management. The implications of these issues and the importance of having a certification process are discussed. PMID:20550724

  8. Do we need a critical care ultrasound certification program? Implications from an Australian medical-legal perspective

    PubMed Central

    2010-01-01

    Medical practitioners have a duty to maintain a certain standard of care in providing their services. With critical care ultrasound gaining popularity in the ICU, it is envisaged that more intensivists will use the tool in managing their patients. Ultrasound, especially echocardiography, can be an 'easy to learn, difficult to manage' skill, and the competency in performing the procedure varies greatly. In view of this, several recommendations for competency statements have been published in recent years to advocate the need for a unified approach to training and certification. In this paper, we take a slightly different perspective, from an Australian medical-legal viewpoint, to argue for the need to implement a critical care ultrasound certification program. We examine various issues that can potentially lead to a breach of the standard of care, hence exposing the practitioners and/or the healthcare institutions to lawsuits in professional negligence or breach of contract. These issues, among others, include the failure to use ultrasound in appropriate situations, the failure of hospitals to ensure practitioners are properly trained in the skills, the failure of practitioners to perform an ultrasound study that is of a reasonable standard, and the failure of practitioners to keep themselves abreast of the latest developments in treatment and management. The implications of these issues and the importance of having a certification process are discussed. PMID:20550724

  9. The Future of Medical Diagnostics: Large Digitized Databases

    PubMed Central

    Kerr, Wesley T.; Lau, Edward P.; Owens, Gwen E.; Trefler, Aaron

    2012-01-01

    The electronic health record mandate within the American Recovery and Reinvestment Act of 2009 will have a far-reaching affect on medicine. In this article, we provide an in-depth analysis of how this mandate is expected to stimulate the production of large-scale, digitized databases of patient information. There is evidence to suggest that millions of patients and the National Institutes of Health will fully support the mining of such databases to better understand the process of diagnosing patients. This data mining likely will reaffirm and quantify known risk factors for many diagnoses. This quantification may be leveraged to further develop computer-aided diagnostic tools that weigh risk factors and provide decision support for health care providers. We expect that creation of these databases will stimulate the development of computer-aided diagnostic support tools that will become an integral part of modern medicine. PMID:23012584

  10. Fluorocarbon compounds in MRI diagnostics and medical therapy

    NASA Astrophysics Data System (ADS)

    Pirogov, Yu

    2016-02-01

    The lecture describes the application of fluorocarbon compounds as blood substitutes and contrasting preparations in MRI diagnostics. A blood substitute product fluorocarbon Perfluorane® has shown effectiveness in oxygen delivery to the tissues of living organisms, and cardioprotective effect which does not depend on the patient's blood group. Inclusion of paramagnetic atoms (gadolinium, iron, etc.) to the Perfluorane® chemical formula creates a new compound with high MRI contrast efficiencies at Larmor frequencies of protons so and fluorine-19 nuclei.

  11. AMUM LECTURE: Therapeutic ultrasound

    NASA Astrophysics Data System (ADS)

    Crum, Lawrence A.

    2004-01-01

    The use of ultrasound in medicine is now quite commonplace, especially with the recent introduction of small, portable and relatively inexpensive, hand-held diagnostic imaging devices. Moreover, ultrasound has expanded beyond the imaging realm, with methods and applications extending to novel therapeutic and surgical uses. These applications broadly include: tissue ablation, acoustocautery, lipoplasty, site-specific and ultrasound mediated drug activity, extracorporeal lithotripsy, and the enhancement of natural physiological functions such as wound healing and tissue regeneration. A particularly attractive aspect of this technology is that diagnostic and therapeutic systems can be combined to produce totally non-invasive, imageguided therapy. This general lecture will review a number of these exciting new applications of ultrasound and address some of the basic scientific questions and future challenges in developing these methods and technologies for general use in our society. We shall particularly emphasize the use of High Intensity Focused Ultrasound (HIFU) in the treatment of benign and malignant tumors as well as the introduction of acoustic hemostasis, especially in organs which are difficult to treat using conventional medical and surgical techniques.

  12. Medical diagnostic decision support systems--past, present, and future: a threaded bibliography and brief commentary.

    PubMed Central

    Miller, R A

    1994-01-01

    Articles about medical diagnostic decision support (MDDS) systems often begin with a disclaimer such as, "despite many years of research and millions of dollars of expenditures on medical diagnostic systems, none is in widespread use at the present time." While this statement remains true in the sense that no single diagnostic system is in widespread use, it is misleading with regard to the state of the art of these systems. Diagnostic systems, many simple and some complex, are now ubiquitous, and research on MDDS systems is growing. The nature of MDDS systems has diversified over time. The prospects for adoption of large-scale diagnostic systems are better now than ever before, due to enthusiasm for implementation of the electronic medical record in academic, commercial, and primary care settings. Diagnostic decision support systems have become an established component of medical technology. This paper provides a review and a threaded bibliography for some of the important work on MDDS systems over the years from 1954 to 1993. PMID:7719792

  13. Optimizing breast cancer follow-up: diagnostic value and costs of additional routine breast ultrasound.

    PubMed

    Wojcinski, Sebastian; Farrokh, Andre; Hille, Ursula; Hirschauer, Elke; Schmidt, Werner; Hillemanns, Peter; Degenhardt, Friedrich

    2011-02-01

    A total of 2,546,325 breast cancer survivors are estimated to live in the United States. The organized breast cancer follow-up programs do not generally include breast ultrasound in asymptomatic women. The purpose of our prospective study was to investigate the efficacy of breast ultrasound in detecting previously occult recurrences. A total of 735 eligible patients with a history of breast cancer were recruited. We assessed the same patient population before (routine follow-up program) and after (study follow-up program) the introduction of an additional ultrasound examination. In the routine follow-up program 245 of 735 patients (33.3% [95% confidence-interval (CI): 29.9-36.7]) had an ultrasound due to abnormal local or mammographic findings. 490 of 735 patients (66.7% [95% CI: 63.3-70.1]) were initially considered asymptomatic and received an additional ultrasound exclusively within the study follow-up program. All positive examination results were followed by accelerated core needle biopsy. The routine follow-up program led to a biopsy in 66 of 735 patients (9.0%) revealing a recurrent cancer in 27 cases (3.7%). The study follow-up program with the additional ultrasound led to another 21 biopsies raising the total number of patients who had to undergo a biopsy from 9.0% (95% CI: 6.9-11.1) to 11.8% (95% CI: 9.5-14.2). Finally, we diagnosed a previously occult malignant lesion in an additional six patients following this protocol. Therefore, the rate of detected recurrences rose from 3.7% (95% CI: 2.3-5.0) in the routine follow-up program to 4.5% (95% CI: 3.0-6.0) in the study follow-up program (p = 0.041). Negative side effects were the additional costs (the costs per detected malignancy in the routine follow-up program were $2455.69; the costs for each additionally detected malignancy in the study follow-up program were $7580.30), the higher overall biopsy rate (9.0 vs. 11.8%) and the elevated benign biopsies rate (59.1% vs. 71.4%). Regarding these results, the

  14. The Relationship between Diagnostic Accuracy and Confidence in Medical Students.

    ERIC Educational Resources Information Center

    Mann, Doug

    Studies in psychology and clinical decision making have shown that research subjects and physicians are often overconfident in the accuracy of their judgments. In these studies, groups of 20 first-year and 27 third-year osteopathic medical students at the Ohio University College of Osteopathic Medicine (Athens) were slightly underconfident in…

  15. Medical Student Assessment of Videotape for Teaching in Diagnostic Radiology

    ERIC Educational Resources Information Center

    Moss, J. R.; McLachlan, M. S. F.

    1976-01-01

    A series of six recordings that describe some aspects of the radiology of the chest, using only radiographs, were viewed by a small group of final year medical students. Their scores for factual questions immediately afterwards were compared with their attitudes to the learning experience; higher scores correlated with positive attitudes. (LBH)

  16. 77 FR 6915 - Medical Diagnostic Equipment Accessibility Standards

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-09

    ... accommodations are accessible to individuals with disabilities.\\7\\ See 75 FR 43452 (July 26, 2010). Among other... Rehabilitation Engineering Research Center on Accessible Medical Instrumentation conducted a national survey in.... Consultation With Food and Drug Administration G. ANSI/AAMI HE 75 H. Barriers Affecting Accessibility...

  17. Therapeutic Endoscopic Ultrasound

    PubMed Central

    Cheriyan, Danny

    2015-01-01

    Endoscopic ultrasound (EUS) technology has evolved dramatically over the past 20 years, from being a supplementary diagnostic aid available only in large medical centers to being a core diagnostic and therapeutic tool that is widely available. Although formal recommendations and practice guidelines have not been developed, there are considerable data supporting the use of EUS for its technical accuracy in diagnosing pancreaticobiliary and gastrointestinal pathology. Endosonography is now routine practice not only for pathologic diagnosis and tumor staging but also for drainage of cystic lesions and celiac plexus neurolysis. In this article, we cover the use of EUS in biliary and pancreatic intervention, ablative therapy, enterostomy, and vascular intervention. PMID:27118942

  18. Registration and identification of pulse signal for medical diagnostics

    NASA Astrophysics Data System (ADS)

    Buldakova, Tatyana I.; Suyatinov, Sergey I.

    2002-07-01

    Registration and identification of pulse signal requires the development and the use of special diagnostic equipment and modern methods of processing of the registered data. There are recognized that photoelectric and piezoelectric gauges are the most perspective converters for measurement of pulse signal. In this paper the approach to registration of pulse curves on the basis of the optical gauge is developed. The problem of identification of pulse signal is considered as the problem of recognition of images. The system of identification of pulse waves is offered. It is functioning as a visual system of recognition of images of the man and is based on artificial neural networks.

  19. Evaluation of lymph node status after neoadjuvant chemotherapy in breast cancer patients: comparison of diagnostic performance of ultrasound, MRI and 18F-FDG PET/CT

    PubMed Central

    You, S; Kang, D K; Jung, Y S; An, Y-S; Jeon, G S

    2015-01-01

    Objective: To evaluate the diagnostic performance of ultrasound, MRI and fluorine-18 fludeoxyglucose positron emission tomography (18F-FDG PET)/CT for the diagnosis of metastatic axillary lymph node (ALN) after neoadjuvant chemotherapy (NAC) and to find out histopathological factors affecting the diagnostic performance of these imaging modalities. Methods: From January 2012 to November 2014, 191 consecutive patients with breast cancer who underwent NAC before surgery were retrospectively reviewed. We included 139 patients with ALN metastasis that was confirmed on fine needle aspiration or core needle biopsy at initial diagnosis. Results: After NAC, 39 (28%) patients showed negative conversion of ALN on surgical specimens of sentinel lymph node (LN) or ALN. The sensitivity of ultrasound, MRI and PET/CT was 50% (48/96), 72% (70/97) and 22% (16/73), respectively. The specificity of ultrasound, MRI and PET/CT was 77% (30/39), 54% (21/39) and 85% (22/26), respectively. The Az value of combination of ultrasound and PET/CT was the highest (0.634) followed by ultrasound (0.626) and combination of ultrasound, MRI and PET/CT (0.617). The size of tumour deposit in LN and oestrogen receptor was significantly associated with the diagnostic performance of ultrasound (p < 0.001 and p = 0.009, respectively) and MRI (p = 0.045 and p = 0.036, respectively). The percentage diameter decrease, size of tumour deposit in LN, progesterone receptor, HER2 and histological grade were significantly associated with the diagnostic performance of PET/CT (p = 0.023, p = 0.002, p = 0.036, p = 0.044 and p = 0.008, respectively). On multivariate logistic regression analysis, size of tumour deposit within LN was identified as being independently associated with diagnostic performance of ultrasound [odds ratio, 13.07; 95% confidence interval (CI), 2.95–57.96] and PET/CT (odds ratio, 6.47; 95% CI, 1.407–29.737). Conclusion: Combination of three imaging modalities

  20. 21 CFR 1000.50 - Recommendation for the use of specific area gonad shielding on patients during medical diagnostic...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... shielding on patients during medical diagnostic x-ray procedures. 1000.50 Section 1000.50 Food and Drugs... shielding on patients during medical diagnostic x-ray procedures. Specific area gonad shielding covers an... that may cause genetic mutations during many medical x-ray procedures in which the gonads lie within...

  1. 21 CFR 1000.50 - Recommendation for the use of specific area gonad shielding on patients during medical diagnostic...

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... shielding on patients during medical diagnostic x-ray procedures. 1000.50 Section 1000.50 Food and Drugs... shielding on patients during medical diagnostic x-ray procedures. Specific area gonad shielding covers an... that may cause genetic mutations during many medical x-ray procedures in which the gonads lie within...

  2. 21 CFR 1000.50 - Recommendation for the use of specific area gonad shielding on patients during medical diagnostic...

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... shielding on patients during medical diagnostic x-ray procedures. 1000.50 Section 1000.50 Food and Drugs... shielding on patients during medical diagnostic x-ray procedures. Specific area gonad shielding covers an... that may cause genetic mutations during many medical x-ray procedures in which the gonads lie within...

  3. 21 CFR 1000.50 - Recommendation for the use of specific area gonad shielding on patients during medical diagnostic...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... shielding on patients during medical diagnostic x-ray procedures. 1000.50 Section 1000.50 Food and Drugs... shielding on patients during medical diagnostic x-ray procedures. Specific area gonad shielding covers an... that may cause genetic mutations during many medical x-ray procedures in which the gonads lie within...

  4. 21 CFR 1000.50 - Recommendation for the use of specific area gonad shielding on patients during medical diagnostic...

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... shielding on patients during medical diagnostic x-ray procedures. 1000.50 Section 1000.50 Food and Drugs... shielding on patients during medical diagnostic x-ray procedures. Specific area gonad shielding covers an... that may cause genetic mutations during many medical x-ray procedures in which the gonads lie within...

  5. Application of the local similarity filter for the suppression of multiplicative noise in medical ultrasound images

    NASA Astrophysics Data System (ADS)

    Kusnik, Damian; Smolka, Bogdan; Cyganek, Boguslaw

    2016-04-01

    In this paper we address the problem of the reduction of multiplicative noise in digital images. This kind of image distortion, also known as speckle noise, severely decreases the quality of medical ultrasound images and therefore their effective enhancement and restoration is of vital importance for proper visual inspection and quantitative measurements. The structure of the proposed Pixel-Patch Similarity Filter (PPSF) is a weighted average of pixels in a processing block and the weights are determined calculating the sum of squared differences between the mean of a patch and the intensities of pixels of the local window at the block center. The structure of the proposed design is similar to the bilateral and non-local means filters, however we neglect the topographic distance between pixels, which decreases substantially its computational complexity. The new technique was evaluated on standard gray scale test images contaminated with multiplicative noise modelled using Gaussian and uniform distribution. Its efficiency was also assessed utilizing a set of simulated ultrasonographic images distorted by means of the Field II simulation software and real ultrasound images of a finger joint. The comparison with the state-of-the-art techniques revealed very high efficiency of the proposed filtering framework, especially for strongly degraded images. Visually, the homogeneous areas are smoother, while image edges and small details are better preserved. The experiments have shown that satisfactory results were obtained with patches consisting of only 9 samples belonging to a relatively small processing block of 7x7 pixels, which ensures low computational complexity of the proposed denoising scheme and allows its application in real-time image processing scenarios.

  6. [Interventional ultrasound].

    PubMed

    Blázquez Sánchez, N; Fernández Canedo, I; Valdés Vilches, L; de Troya Martín, M

    2015-11-01

    High-frequency ultrasound has become increasingly used in dermatology. This technique is accessible, non-invasive, and rapid and provides information in real time. Consequently, it has become of great diagnostic value in dermatology. However, high-frequency ultrasound also has a promising future as a complementary technique in interventional diagnostic procedures, even though its application in this field has been little studied by dermatologists. PMID:26895944

  7. Impact of Endobronchial Ultrasound Guided Transbronchial Needle Aspiration on Diagnostic Yield of Bronchoscopy in Patients with Mediastinal Lymph Node Enlargement.

    PubMed

    Osinka, K; Zielińska-Krawczyk, M; Korczyński, P; Górnicka, B; Krenke, R

    2016-01-01

    Endobronchial ultrasound guided transbronchial needle aspiration (EBUS-TBNA) had an enormous impact on the current advancement in diagnostic bronchoscopy. The aims of the present study were: (1) to evaluate the added value of EBUS-TBNA to routine diagnostic bronchoscopy performed in patients with mediastinal lymph node enlargement and (2) to identify factors that affect the diagnostic yield of EBUS-TBNA. We retrospectively analyzed 712 EBUS-TBNA procedures out of the 4081 bronchoscopies performed in the years 2009-2014. The number of EBUS-TBNA procedures increased from 61 (8.8 % of all bronchoscopies) in 2009 to 160 (21.4 %) in 2014. In 625 (87.8 %) patients adequate cytological material was obtained. Based on cytological examination of EBUS-TBNA aspirates, specific diagnosis was made in 367 (51.5 %) patients. The forceps biopsy of endobronchial lesions provided specific diagnosis in only 204 (28.6 %) patients. The percentage of patients with EBUS-TBNA based diagnosis increased steadily from 34.4 % in 2009 to 65.0 % in 2014 (p < 0.0001). The median lymph node diameter in patients with positive EBUS-TBNA findings was 20 (IQR 15-30) mm and was significantly larger than that in patients with negative EBUS-TBNA results (15 (IQR 10-20) mm, p = 0.0001). The highest diagnostic yield (78.5 %) was found in patients with lymph node dimension between 31 mm and 40 mm. We conclude that EBUS-TBNA is a valuable diagnostic method in an unselected group of patients with mediastinal lymph node enlargement. The percentage of positive EBUS-TBNA diagnoses is related to lymph node dimensions. The overall efficacy of EBUS-TBNA improves with increasing years of experience. PMID:26987324

  8. Robust non-homomorphic approach for speckle reduction in medical ultrasound images.

    PubMed

    Gupta, S; Chauhan, R C; Saxena, S C

    2005-03-01

    Most existing wavelet-based image denoising techniques are developed for additive white Gaussian noise. In applications to speckle reduction in medical ultrasound (US) images, the traditional approach is first to perform the logarithmic transform (homomorphic processing) to convert the multiplicative speckle noise model to an additive one, and then the wavelet filtering is performed on the log-transformed image, followed by an exponential operation. However, this non-linear operation leads to biased estimation of the signal and increases the computational complexity of the filtering method. To overcome these drawbacks, an efficient, non-homomorphic technique for speckle reduction in medical US images is proposed. The method relies on the true characterisation of the marginal statistics of the signal and speckle wavelet coefficients. The speckle component was modelled using the generalised Nakagami distribution, which is versatile enough to model the speckle statistics under various scattering conditions of interest in medical US images. By combining this speckle model with the generalised Gaussian signal first, the Bayesian shrinkage functions were derived using the maximum a posteriori (MAP) criterion. The resulting Bayesian processor used the local image statistics to achieve soft-adaptation from homogeneous to highly heterogeneous areas. Finally, the results showed that the proposed method, named GNDShrink, yielded a signal-to-noise ratio (SNR) gain of 0.42dB over the best state-of-the-art despeckling method reported in the literature, 1.73dB over the Lee filter and 1.31dB over the Kaun filter at an input SNR of 12.0dB, when tested on a US image. Further, the visual comparison of despeckled US images indicated that the new method suppressed the speckle noise well, while preserving the texture and organ surfaces. PMID:15865126

  9. General Principles of Radiation Protection in Fields of Diagnostic Medical Exposure

    PubMed Central

    2016-01-01

    After the rapid development of medical equipment including CT or PET-CT, radiation doses from medical exposure are now the largest source of man-made radiation exposure. General principles of radiation protection from the hazard of ionizing radiation are summarized as three key words; justification, optimization, and dose limit. Because medical exposure of radiation has unique considerations, diagnostic reference level is generally used as a reference value, instead of dose limits. In Korea, medical radiation exposure has increased rapidly. For medical radiation exposure control, Korea has two separate control systems. Regulation is essential to control medical radiation exposure. Physicians and radiologists must be aware of the radiation risks and benefits associated with medical exposure, and understand and implement the principles of radiation protection for patients. The education of the referring physicians and radiologists is also important. PMID:26908991

  10. Nonlinear effects in ultrasound fields of diagnostic-type transducers used for kidney stone propulsion: Characterization in water

    SciTech Connect

    Karzova, M.; Cunitz, B.; Kreider, W.; Bailey, M.; Yuldashev, P.; Andriyakhina, Y.; Sapozhnikov, O.; Khokhlova, V.

    2015-10-28

    Newer imaging and therapeutic ultrasound technologies require higher in situ pressure levels compared to conventional diagnostic values. One example is the recently developed use of focused ultrasonic radiation force to move kidney stones and residual fragments out of the urinary collecting system. A commercial diagnostic 2.3 MHz C5-2 array probe is used to deliver the acoustic pushing pulses. The probe comprises 128 elements equally spaced at the 55 mm long convex cylindrical surface with 38 mm radius of curvature. The efficacy of the treatment can be increased by using higher intensity at the focus to provide stronger pushing force; however, nonlinear acoustic saturation can be a limiting factor. In this work nonlinear propagation effects were analyzed for the C5-2 transducer using a combined measurement and modeling approach. Simulations were based on the 3D Westervelt equation; the boundary condition was set to match the focal geometry of the beam as measured at a low power output. Focal waveforms simulated for increased output power levels were compared with the fiber-optic hydrophone measurements and were found in good agreement. It was shown that saturation effects do limit the acoustic pressure in the focal region of the transducer. This work has application to standard diagnostic probes and imaging.

  11. Nonlinear Effects in Ultrasound Fields of Diagnostic-type Transducers Used for Kidney Stone Propulsion: Characterization in Water

    PubMed Central

    Karzova, M.; Cunitz, B.; Yuldashev, P.; Andriyakhina, Y.; Kreider, W.; Sapozhnikov, O.; Bailey, M.; Khokhlova, V.

    2016-01-01

    Newer imaging and therapeutic ultrasound technologies require higher in situ pressure levels compared to conventional diagnostic values. One example is the recently developed use of focused ultrasonic radiation force to move kidney stones and residual fragments out of the urinary collecting system. A commercial diagnostic 2.3 MHz C5-2 array probe is used to deliver the acoustic pushing pulses. The probe comprises 128 elements equally spaced at the 55 mm long convex cylindrical surface with 38 mm radius of curvature. The efficacy of the treatment can be increased by using higher transducer output to provide stronger pushing force; however, nonlinear acoustic saturation effect can be a limiting factor. In this work nonlinear propagation effects were analyzed for the C5-2 transducer using a combined measurement and modeling approach. Simulations were based on the 3D Westervelt equation; the boundary condition was set to match low power pressure beam scans. Focal waveforms simulated for increased output power levels were compared with the fiber-optic hydrophone measurements and were found in good agreement. It was shown that saturation effects do limit the acoustic pressure in the focal region of the transducer. This work has application to standard diagnostic probes and imaging. PMID:27087711

  12. Nonlinear effects in ultrasound fields of diagnostic-type transducers used for kidney stone propulsion: Characterization in water

    NASA Astrophysics Data System (ADS)

    Karzova, M.; Cunitz, B.; Yuldashev, P.; Andriyakhina, Y.; Kreider, W.; Sapozhnikov, O.; Bailey, M.; Khokhlova, V.

    2015-10-01

    Newer imaging and therapeutic ultrasound technologies require higher in situ pressure levels compared to conventional diagnostic values. One example is the recently developed use of focused ultrasonic radiation force to move kidney stones and residual fragments out of the urinary collecting system. A commercial diagnostic 2.3 MHz C5-2 array probe is used to deliver the acoustic pushing pulses. The probe comprises 128 elements equally spaced at the 55 mm long convex cylindrical surface with 38 mm radius of curvature. The efficacy of the treatment can be increased by using higher intensity at the focus to provide stronger pushing force; however, nonlinear acoustic saturation can be a limiting factor. In this work nonlinear propagation effects were analyzed for the C5-2 transducer using a combined measurement and modeling approach. Simulations were based on the 3D Westervelt equation; the boundary condition was set to match the focal geometry of the beam as measured at a low power output. Focal waveforms simulated for increased output power levels were compared with the fiber-optic hydrophone measurements and were found in good agreement. It was shown that saturation effects do limit the acoustic pressure in the focal region of the transducer. This work has application to standard diagnostic probes and imaging.

  13. Advanced synchronous luminescence imaging for chemical and medical diagnostics

    DOEpatents

    Vo-Dinh, Tuan

    2006-09-05

    A diagnostic method and associated system includes the steps of exposing at least one sample location with excitation radiation through a single optical waveguide or a single optical waveguide bundle, wherein the sample emits emission radiation in response to the excitation radiation. The same single optical waveguide or the single optical waveguide bundle receives at least a portion of the emission radiation from the sample, thus providing co-registration of the excitation radiation and the emission radiation. The wavelength of the excitation radiation and emission radiation is synchronously scanned to produce a spectrum upon which an image can be formed. An increased emission signal is generated by the enhanced overlap of the excitation and emission focal volumes provided by co-registration of the excitation and emission signals thus increasing the sensitivity as well as decreasing the exposure time necessary to obtain an image.

  14. Isotope-selective sensor for medical diagnostics based on PAS

    NASA Astrophysics Data System (ADS)

    Wolff, M.; Groninga, H. G.; Harde, H.

    2005-06-01

    Development of new optical sensor technologies has a major impact on the progression of diagnostic methods. Of the permanently increasing number of non-invasive 13C-breath tests, the Urea Breath Test for detection of Helicobacter pylori is the most prominent. However, many recent developments go beyond gastroenterological applications. We present a new detection scheme for breath analysis that employs an especially compact and simple set-up based on Photoacoustic Spectroscopy. Using a wavelength-modulated DFB-diode laser and taking advantage of acoustical resonances of the sample cell, we performed very sensitive isotope-selective measurements on CO2. Detection limits for 13CO2 of a few ppm and for the variation of the 13CO2 concentration of approximately 1% were achieved.

  15. Towards real-time medical diagnostics using hyperspectral imaging technology

    NASA Astrophysics Data System (ADS)

    Bjorgan, Asgeir; Randeberg, Lise L.

    2015-07-01

    Hyperspectral imaging provides non-contact, high resolution spectral images which has a substantial diagnostic potential. This can be used for e.g. diagnosis and early detection of arthritis in finger joints. Processing speed is currently a limitation for clinical use of the technique. A real-time system for analysis and visualization using GPU processing and threaded CPU processing is presented. Images showing blood oxygenation, blood volume fraction and vessel enhanced images are among the data calculated in real-time. This study shows the potential of real-time processing in this context. A combination of the processing modules will be used in detection of arthritic finger joints from hyperspectral reflectance and transmittance data.

  16. The Diagnostic Value of Nerve Ultrasound in an Atypical Palmar Cutaneous Nerve Lesion.

    PubMed

    Zanette, Giampietro; Tamburin, Stefano

    2016-07-01

    Detailed knowledge of the fascicular anatomy of peripheral nerves is important for microsurgical repair and functional electrostimulation.We report a patient with a lesion on the left palmar cutaneous branch of the median nerve (PCBMN) and sensory signs expanding outside the PCBMN cutaneous innervation territory. Nerve conduction study showed the absence of left PCBMN sensory nerve action potential, but apparently, no median nerve (MN) involvement. Nerve ultrasound documented a neuroma of the left PCBMN and a coexistent lateral neuroma of the left MN in the carpal tunnel after the PCBMN left the main nerve trunk.Nerve ultrasound may offer important information in patients with peripheral nerve lesions and atypical clinical and/or nerve conduction study findings. The present case may shed some light on the somatotopy of MN fascicles at the wrist. PMID:26945219

  17. WE-D-18C-01: Art of Imaging: Diagnostic Ultrasound Image Artifacts

    SciTech Connect

    Zagzebski, J; Lu, Z

    2014-06-15

    Assumptions followed during construction of B-mode and color flow images are that the pulse-echo transit time can be converted to reflector depth through uniform tissue models, echoes originate only from locations along the transmit-receive axes of pulse propagation, and first order correction schemes adequately account for acoustic wave attenuation and absorption. The latter allows the display brightness to encode tissue echogenicity. This course will challenge participants to identify imaging artifacts whose origins stem from the more complex and realistic propagating and scattering conditions common in clinical ultrasound. Speckle, a very common artifact but a clinically employed feature, originates from simultaneous echoes from diffuse scatterers and is a result of coherent detection of signals. One of the most bothersome artifacts are those due to reverberations especially that originating from superficial tissue interfaces. Methods to overcome these will be discussed. This presentation also will describe and illustrate speed of sound, refraction, enhancement, shadowing, mirroring, beam width, beam-forming, and slice thickness artifacts. All are useful examples of limitations introduced by acoustic waves propagating through complex tissue paths. New formats for physician board certification exams are demanding the inclusion of image-based examples of ultrasound physics. Instructors' knowledge of, and access to examples of ultrasound artifacts are important in this effort. The presentation will incorporate an audience response system to challenge participants in correct identification of some of these artifacts. Learning Objectives: Review basic mechanisms for producing ultrasound images. Identify the etiology of speckle, reverberation noise, beam width and slice thickness artifacts, and artifacts associated with pulse propagation. Discuss methods that reduce the impact of artifacts OR employ artifacts effectively to facilitate clinical diagnosis.

  18. Use of high-resolution ultrasound as a diagnostic tool in veterinary ophthalmology.

    PubMed

    Bentley, Ellison; Miller, Paul E; Diehl, Kathryn A

    2003-12-01

    The recent development of a 20-MHz, high-frequency ultrasound probe has allowed tissue to be visualized at resolutions of 20 to 80 microm, which is similar to a low-power histologic view. This high degree of resolution, however, limits tissue penetration to 5 to 10 mm, which is ideal for examination of the anterior segment of the eye. The detail provided by high-resolution ultrasound readily permits the clinician to distinguish between various anterior segment entities that may appear similar but are treated quite differently, such as anterior uveal tumors, iridociliary cysts, and iris bombé. High-frequency ultrasound is also a valuable aid in creating a surgical plan for treatment of ocular disorders in which the cornea is opaque, such as feline corneal sequestrum and tumor invasion into the cornea. Other applications of this technology include elucidation of the pathogenesis of glaucoma in veterinary patients and evaluation of regions of the lens that are difficult to examine directly. PMID:14664449

  19. Target detection in diagnostic ultrasound: Evaluation of a method based on the CLEAN algorithm.

    PubMed

    Masoom, Hassan; Adve, Raviraj S; Cobbold, Richard S C

    2013-02-01

    A technique is proposed for the detection of abnormalities (targets) in ultrasound images using little or no a priori information and requiring little operator intervention. The scheme is a combination of the CLEAN algorithm, originally proposed for radio astronomy, and constant false alarm rate (CFAR) processing, as developed for use in radar systems. The CLEAN algorithm identifies areas in the ultrasound image that stand out above a threshold in relation to the background; CFAR techniques allow for an adaptive, semi-automated, selection of the threshold. Neither appears to have been previously used for target detection in ultrasound images and never together in any context. As a first step towards assessing the potential of this method we used a widely used method of simulating B-mode images (Field II). We assumed the use of a 256 element linear array operating at 3.0MHz into a water-like medium containing a density of point scatterers sufficient to simulate a background of fully developed speckle. Spherical targets with diameters ranging from 0.25 to 6.0mm and contrasts ranging from 0 to 12dB relative to the background were used as test objects. Using a contrast-detail analysis, the probability of detection curves indicate these targets can be consistently detected within a speckle background. Our results indicate that the method has considerable promise for the semi-automated detection of abnormalities with diameters greater than a few millimeters, depending on the contrast. PMID:22853949

  20. Ultrasound annual, 1986

    SciTech Connect

    Sanders, R.C.; Hill, M.C.

    1986-01-01

    This book provides an analyses of developments in the field of diagnostic ultrasound. Endoscopic ultrasound and ultrasound-guided aspiration of ovarian follicles for in vitro fertilization are addressed. The use of Doppler ultrasound to measure blood flow in obstetrics is also examined.

  1. On-line integration of computer controlled diagnostic devices and medical information systems in undergraduate medical physics education for physicians.

    PubMed

    Hanus, Josef; Nosek, Tomas; Zahora, Jiri; Bezrouk, Ales; Masin, Vladimir

    2013-01-01

    We designed and evaluated an innovative computer-aided-learning environment based on the on-line integration of computer controlled medical diagnostic devices and a medical information system for use in the preclinical medical physics education of medical students. Our learning system simulates the actual clinical environment in a hospital or primary care unit. It uses a commercial medical information system for on-line storage and processing of clinical type data acquired during physics laboratory classes. Every student adopts two roles, the role of 'patient' and the role of 'physician'. As a 'physician' the student operates the medical devices to clinically assess 'patient' colleagues and records all results in an electronic 'patient' record. We also introduced an innovative approach to the use of supportive education materials, based on the methods of adaptive e-learning. A survey of student feedback is included and statistically evaluated. The results from the student feedback confirm the positive response of the latter to this novel implementation of medical physics and informatics in preclinical education. This approach not only significantly improves learning of medical physics and informatics skills but has the added advantage that it facilitates students' transition from preclinical to clinical subjects. PMID:22200603

  2. Introducing a Fresh Cadaver Model for Ultrasound-guided Central Venous Access Training in Undergraduate Medical Education

    PubMed Central

    Miller, Ryan; Ho, Hang; Ng, Vivienne; Tran, Melissa; Rappaport, Douglas; Rappaport, William J.A.; Dandorf, Stewart J.; Dunleavy, James; Viscusi, Rebecca; Amini, Richard

    2016-01-01

    Introduction Over the past decade, medical students have witnessed a decline in the opportunities to perform technical skills during their clinical years. Ultrasound-guided central venous access (USG-CVA) is a critical procedure commonly performed by emergency medicine, anesthesia, and general surgery residents, often during their first month of residency. However, the acquisition of skills required to safely perform this procedure is often deficient upon graduation from medical school. To ameliorate this lack of technical proficiency, ultrasound simulation models have been introduced into undergraduate medical education to train venous access skills. Criticisms of simulation models are the innate lack of realistic tactile qualities, as well as the lack of anatomical variances when compared to living patients. The purpose of our investigation was to design and evaluate a life-like and reproducible training model for USG-CVA using a fresh cadaver. Methods This was a cross-sectional study at an urban academic medical center. An 18-point procedural knowledge tool and an 18-point procedural skill evaluation tool were administered during a cadaver lab at the beginning and end of the surgical clerkship. During the fresh cadaver lab, procedure naïve third-year medical students were trained on how to perform ultrasound-guided central venous access of the femoral and internal jugular vessels. Preparation of the fresh cadaver model involved placement of a thin-walled latex tubing in the anatomic location of the femoral and internal jugular vein respectively. Results Fifty-six third-year medical students participated in this study during their surgical clerkship. The fresh cadaver model provided high quality and lifelike ultrasound images despite numerous cannulation attempts. Technical skill scores improved from an average score of 3 to 12 (p<0.001) and procedural knowledge scores improved from an average score of 4 to 8 (p<0.001). Conclusion The use of this novel cadaver

  3. Multiplexed label-free optical biosensor for medical diagnostics.

    PubMed

    Bottazzi, Barbara; Fornasari, Lucia; Frangolho, Ana; Giudicatti, Silvia; Mantovani, Alberto; Marabelli, Franco; Marchesini, Gerardo; Pellacani, Paola; Therisod, Rita; Valsesia, Andrea

    2014-01-01

    This paper describes a new multiplexed label-free biosensor. The detection technology is based on nanostructured gold-polymer surfaces. These surfaces support surface plasmon resonance modes that can be probed by a miniaturized optical setup. The optical characterization of the sensing chip shows the sensitivity and the limit-of-detection to refractive index changes. Moreover, by studying the progressive adhesion of molecular monolayers of polyelectrolytes, the decay of the plasmonic mode electric field above the surface has been reconstructed. A multiplexed label-free biosensing device is then described and characterized in terms of sensitivity, lateral resolution, and sensitivity to a model biological assay. The sensitivity in imaging mode of the device is of the order of 10-6 refractive index units, while the measured lateral resolution is 6.25 μm within a field of view of several tenths of mm2, making the instrument unique in terms of multiplexing capability. Finally, the proof-of-concept application of the technology as a point-of-care diagnostic tool for an inflammatory marker is demonstrated. PMID:24474511

  4. Low Temperature Atmospheric Argon Plasma: Diagnostics and Medical Applications

    NASA Astrophysics Data System (ADS)

    Ermolaeva, Svetlana; Petrov, Oleg; Zigangirova, Nailya; Vasiliev, Mikhail; Sysolyatina, Elena; Antipov, Sergei; Alyapyshev, Maxim; Kolkova, Natalia; Mukhachev, Andrei; Naroditsky, Boris; Shimizu, Tetsuji; Grigoriev, Anatoly; Morfill, Gregor; Fortov, Vladimir; Gintsburg, Alexander

    This study was devoted to diagnostic of low temperature plasma produced by microwave generator and investigation of its bactericidal effect against bacteria in biofilms and within eukaryotic cells. The profile of gas temperature near the torch outlet was measured. The spectrum in a wide range of wavelengths was derived by the method of optical emission spec-troscopy. Probe measurements of the floating potential of plasma were car-ried out. The estimation and adaptation of parameters of plasma flow (tem-perature, velocity, ion number density) according to medico-technical requirements were produced. The model of immersed surface-associated biofilms formed by Gram-negative bacteria, Pseudomonas aeruginosa and Burkholderia cenocepacia, and Gram-positive bacteria, Staphylococcus aureus, was used to assess bactericidal effects of plasma treatment. Reduction in the concentration of live bacteria in biofilms treated with plasma for 5 min was demonstrated by measuring Live/Dead fluorescent labeling and using direct plating. The intracellular infection model with the pathogenic bacterium, Chlamydia trachomatis, was used to study the efficacy of microwave argon plasma against intracellular parasites. A 2 min plasma treatment of mouse cells infected with C. trachomatis reduced infectious bacteria by a factor of 2×106. Plasma treatment diminished the number of viable host cells by about 20%. When the samples were covered with MgF2 glass to obstruct active particles and UV alone was applied, the bactericidal effect was re-duced by 5×104 fold compared to the whole plasma.

  5. Polymeric rapid prototyping for inexpensive and portable medical diagnostics

    NASA Astrophysics Data System (ADS)

    Ma, Tianchi; Northrup, Victoria; Fung, Andrew O.; Glerum, D. Moira; Backhouse, Christopher J.

    2012-10-01

    The advent of inexpensive CO2 laser systems has led to a wide range of demonstrations of microfabricated lab on chip systems built of acrylic. However, there has been little application of these systems to building microfluidics for DNA analysis. In this work we explore the use of CO2 laser systems for building microfluidics for DNA analysis and relate the artifacts of the fabrication technology to the performance of the system. We show that surface roughness that leads to significant constrictions in the separation channel provides an upper limit of the size of DNA that can be analysed. Below that upper limit, the resolution of the chip is strongly affected by the degree to which the separation channel is exposed to redeposited by-products of the ablation process. We show that by controlling these effects we are reliably able to discern two types of PCR product as a test representative of a real application. By being able to do this is in microfluidic devices the size of a postage stamp we have shown that we can now use CO2 laser systems for the development of extremely inexpensive diagnostic systems using a rapid prototyping approach.

  6. Medical devices; general and plastic surgery devices; classification of the low energy ultrasound wound cleaner. Final rule.

    PubMed

    2005-11-01

    The Food and Drug Administration (FDA) is classifying the low energy ultrasound wound cleaner into class II (special controls). The special control that will apply to the device is the guidance document entitled "Class II Special Controls Guidance Document: Low Energy Ultrasound Wound Cleaner." The agency is taking this action in response to a petition submitted under the Federal Food, Drug, and Cosmetic Act (the act) as amended by the Medical Device Amendments of 1976, the Safe Medical Devices Act of 1990, and the Food and Drug Administration Modernization Act of 1997 (FDAMA). The agency is classifying this device into class II (special controls) in order to provide a reasonable assurance of safety and effectiveness of the device. Elsewhere in this issue of the Federal Register, FDA is announcing the availability of the guidance document that will serve as the special control for the class II device. PMID:16273747

  7. The diagnostic challenges presented by patients with medically unexplained symptoms in general practice

    PubMed Central

    Aiarzaguena, José M.; Grandes, Gonzalo; Salazar, Agustín; Gaminde, Idoia; Sánchez, Álvaro

    2008-01-01

    Objective To describe the complexity of somatizing patients’ symptomatology and the difficulties involved in the diagnostic process. Design Cross-sectional study of patients with medically unexplained symptoms. Setting Basque Health Service primary care centres in Bizkaia, Spain. Subjects The study comprised 156 patients selected at random from a list of 468 patients who had presented, over the course of their lives, six or more medically unexplained somatic symptoms for females and four or more for males, identified retrospectively by their practitioners. Main outcome measures Physicians interviewed these patients using the somatoform symptoms section of the Composite International Diagnostic Interview (CIDI), and the Primary Care Evaluation of Mental Disorders (PRIME-MD). The Medical Outcomes Survey Short Form 36 (SF-36) was filled in at home. Organic diseases whose diagnosis was established during the previous year were included in the study by consulting patients’ medical records. Results Patients were found to have a median of three medically explained and 12 medically unexplained symptoms. Mental disorders were found in 83% of cases, associated with other morbidity categories in 78%. The predictive value of symptoms was lower than 26% for diagnosing broad disease categories. Conclusions These results depict an extremely difficult scenario for dichotomous diagnostic strategies aimed at classifying patients’ symptoms as either organic or functional. Rather than struggling to choose one of these hypotheses, it is suggested that both of them should always be addressed concurrently. PMID:18570008

  8. Synthetic transmit aperture technique in medical ultrasound imaging implemented on a GPU

    NASA Astrophysics Data System (ADS)

    Li, Ying; Chen, Xiaodong; Zhang, Chuang; Wang, Yi; Jiao, Zhihai; Yu, Daoyin

    2014-11-01

    In the medical ultrasound imaging, the synthetic transmit aperture (STA) technique is very promising and has been a hot research topic. It is dynamically focused in both transmit and receive yielding an improvement in resolution. But this imaging technique sets high demands on processing capabilities and makes implementation of a full STA system very challenging and costly. Many attempts have been made to reduce the demands on the system making it a more realistic task to implement. In this paper we don't consider how to reduce the demands, but consider how to accelerate the processing speed of the system. The recent introduction of general-purpose graphic processing units (GPU) seems to be quite promising in this view, especially for the affordable programming complexity. In this paper we explain the main computational features of STA processing unit, trying to disclose the degree of parallelism in the operations. On the basis of the compute unified device architecture (CUDA) programming model and the extremely flexible structure of the Single Instruction Multiple Threads (SIMT) model, we show that the optimization of STA processing unit can be performed more efficiently. The input data is read from Matlab, the post-processing and display also use Matlab. Performance shows that, using a single NIVDIA GTX-650 GPU board, this amount to a speed up of more than a factor of 30 compared to a highly optimized beamformer running on our test workstation with a 3.20-GHz Intel Core-i5 processor.

  9. Design and performance of Huffman sequences in medical ultrasound coded excitation.

    PubMed

    Polpetta, Alessandro; Banelli, Paolo

    2012-04-01

    This paper deals with coded-excitation techniques for ultrasound medical echography. Specifically, linear Huffman coding is proposed as an alternative approach to other widely established techniques, such as complementary Golay coding and linear frequency modulation. The code design is guided by an optimization procedure that boosts the signal-to-noise ratio gain (GSNR) and, interestingly, also makes the code robust in pulsed-Doppler applications. The paper capitalizes on a thorough analytical model that can be used to design any linear coded-excitation system. This model highlights that the performance in frequency-dependent attenuating media mostly depends on the pulse-shaping waveform when the codes are characterized by almost ideal (i.e., Kronecker delta) autocorrelation. In this framework, different pulse shapers and different code lengths are considered to identify coded signals that optimize the contrast resolution at the output of the receiver pulse compression. Computer simulations confirm that the proposed Huffman codes are particularly effective, and that there are scenarios in which they may be preferable to the other established approaches, both in attenuating and non-attenuating media. Specifically, for a single scatterer at 150 mm in a 0.7-dB/(MHz·cm) attenuating medium, the proposed Huffman design achieves a main-to-side lobe ratio (MSR) equal to 65 dB, whereas tapered linear frequency modulation and classical complementary Golay codes achieve 35 and 45 dB, respectively. PMID:22547275

  10. Eigenfunction analysis of stochastic backscatter for characterization of acoustic aberration in medical ultrasound imaging

    NASA Astrophysics Data System (ADS)

    Varslot, Trond; Krogstad, Harald; Mo, Eirik; Angelsen, Bjørn A.

    2004-06-01

    Presented here is a characterization of aberration in medical ultrasound imaging. The characterization is optimal in the sense of maximizing the expected energy in a modified beamformer output of the received acoustic backscatter. Aberration correction based on this characterization takes the form of an aberration correction filter. The situation considered is frequently found in applications when imaging organs through a body wall: aberration is introduced in a layer close to the transducer, and acoustic backscatter from a scattering region behind the body wall is measured at the transducer surface. The scattering region consists of scatterers randomly distributed with very short correlation length compared to the acoustic wavelength of the transmit pulse. The scatterer distribution is therefore assumed to be δ correlated. This paper shows how maximizing the expected energy in a modified beamformer output signal naturally leads to eigenfunctions of a Fredholm integral operator, where the associated kernel function is a spatial correlation function of the received stochastic signal. Aberration characterization and aberration correction are presented for simulated data constructed to mimic aberration introduced by the abdominal wall. The results compare well with what is obtainable using data from a simulated point source.

  11. Statistical properties of radio-frequency and envelope-detected signals with applications to medical ultrasound

    SciTech Connect

    Wagner, R.F.; Insana, M.F.; Brown, D.G.

    1987-05-01

    Both radio-frequency (rf) and envelope-detected signal anlayses have lead to successful tissue discrimination in medical ultrasound. The extrapolation from tissue discrimination to a description of the tissue structure requires an analysis of the statistics of complex signals. To that end, first- and second-order statistics of complex random signals are reviewed, and an example is taken from rf signal analysis of the backscattered echoes from diffuse scatterers. In this case the scattering form factor of small scatterers can be easily separated from long-range structure and corrected for the transducer characteristics, thereby yielding an instrument-independent tissue signature. The statistics of the more economical envelope- and square-law-detected signals are derived next and found to be almost identical when normalized autocorrelation functions are used. Of the two nonlinear methods of detection, the square-law or intensity scheme gives rise to statistics that are more transparent to physical insight. Moreover, an analysis of the intensity-correlation structure indicates that the contributions to the total echo signal from the diffuse scatter and from the steady and variable components of coherent scatter can still be separated and used for tissue characterization. However, this anlaysis is not system independent. Finally, the statistical methods of this paper may be applied directly to envelope signals in nuclear-magnetic-resonance imaging because of the approximate equivalence of second-order statistics for magnitude and intensity.

  12. System architecture for intraoperative ultrasound registration in image-based medical navigation.

    PubMed

    Dekomien, Claudia; Roeschies, Benjamin; Winter, Susanne

    2012-08-01

    Medical navigation systems for orthopedic surgery are becoming more and more important with the increasing proportion of older people in the population, and hence the increasing incidence of diseases of the musculoskeletal system. The central problem for such systems is the exact transformation of the preoperatively acquired datasets to the coordinate system of the patient's body, which is crucial for the accuracy of navigation. Our approach, based on the use of intraoperative ultrasound for image registration, is capable of robustly registering bone structures for different applications, e.g., at the spine or the knee. Nevertheless, this new procedure demands additional steps of preparation of preoperative data. To increase the clinical acceptance of this procedure, it is useful to automate most of the data processing steps. In this article, we present the architecture of our system with focus on the automation of the data processing steps. In terms of accuracy, a mean target registration error of 0.68 mm was achieved for automatically segmented and registered phantom data where the reference transformation was obtained by performing point-based registration using artificial structures. As the overall accuracy for subject data cannot be determined non-invasively, automatic segmentation and registration were judged by visual inspection and precision, which showed a promising result of 1.76 mm standard deviation for 100 registration trials based on automatic segmentation of magnetic resonance imaging data of the spine. PMID:22868778

  13. Analysis and Development of Piezoelectric Composites for Medical Ultrasound Transducer Applications

    NASA Astrophysics Data System (ADS)

    Oakley, Clyde Gerald

    Over the past several years 1-3 piezoelectric composites have become increasingly important in medical ultrasound transducer applications. A substantial body of literature has been written regarding construction techniques, predicted and measured performance, and applications. Still, several important issues remain to be answered which are of importance to transducer designers. This thesis deals with several of those issues and presents new conceptual and computational tools specifically related to the design of piezoelectric composites for transducers used in medical imaging. The important topic of the symmetry of stopband edge resonance modes is investigated by use of an exact one-dimensional solution for infinite 2-2 composites. A simple conceptual model relating the stopband structure to the resonance of the individual components is presented and a computationally simple and accurate means of calculating stopband edge resonance frequencies is developed. The techniques are used to investigate the behavior of some composites with double periodicities. Effective medium theories are reviewed and calculations are compared to experimental results. A matrix version of the theory is used to calculate the slowness diagrams for a 1-3 composite and to investigate the design trade -offs which must be made in optimizing composite performance. A novel composite is proposed which consists of free-standing piezoelectric posts surrounded on the sides by air and bounded on front and back by stiff layers. Potential performance improvements and problems are presented. Experimental results showing excellent bandwidth and pulse length but only moderate sensitivity are given along with a proposed explanation for the results. Proposals for further work are suggested.

  14. Medical Diagnostic Breath Analysis by Cavity Ring Down Spectroscopy

    NASA Astrophysics Data System (ADS)

    Guss, Joseph S.; Metsälä, Markus; Halonen, Lauri

    2009-06-01

    Certain medical conditions give rise to the presence of chemicals in the bloodstream. These chemicals - known as biomarkers - may also be present in low concentrations in human breath. Cavity ring down spectroscopy possesses the requisite selectivity and sensitivity to detect such biomarkers in the congested spectrum of a breath sample. The ulcer-causing bacterium, Helicobacter pylori, is a prolific producer of the enzyme urease, which catalyses the breakdown of urea ((NH_2)_2CO) in the stomach as follows: (NH_2)_2CO + H_2O ⟶ CO_2 + 2NH_3 Currently, breath tests seeking altered carbon-isotope ratios in exhaled CO_2 after the ingestion of ^{13}C- or ^{14}C-labeled urea are used to diagnose H. pylori infection. We present recent results from an ongoing collaboration with Tampere Area University Hospital. The study involves 100 patients (both infected and uninfected) and concerns the possible correlation between the bacterial infection and breath ammonia. D. Y. Graham, P. D. Klein, D. J. Evans, Jr, D. G. Evans, L. C. Alpert, A. R. Opekun, T. W. Boutton, Lancet 1(8543), 1174-7 March 1987.

  15. Predictive Modeling of Student Performances for Retention and Academic Support in a Diagnostic Medical Sonography Program

    ERIC Educational Resources Information Center

    Borghese, Peter; Lacey, Sandi

    2014-01-01

    As part of a retention and academic support program, data was collected to develop a predictive model of student performances in core classes in a Diagnostic Medical Sonography (DMS) program. The research goal was to identify students likely to have difficulty with coursework and provide supplemental tutorial support. The focus was on the…

  16. Crossing the Great Divide: Adoption of New Technologies, Therapeutics and Diagnostics at Academic Medical Centers

    ERIC Educational Resources Information Center

    DeMonaco, Harold J.; Koski, Greg

    2007-01-01

    The role of new technology in healthcare continues to expand from both the clinical and financial perspectives. Despite the importance of innovation, most academic medical centers do not have a clearly defined process for technology assessment. Recognizing the importance of new drugs, diagnostics and procedures in the care of patients and in the…

  17. Principles for new optical techniques in medical diagnostics for mHealth applications

    NASA Astrophysics Data System (ADS)

    Balsam, Joshua Michael

    Medical diagnostics is a critical element of effective medical treatment. However, many modern and emerging diagnostic technologies are not affordable or compatible with the needs and conditions found in low-income and middle-income countries and regions. Resource-poor areas require low-cost, robust, easy-to-use, and portable diagnostics devices compatible with telemedicine (i.e. mHealth) that can be adapted to meet diverse medical needs. Many suitable devices will need to be based on optical technologies, which are used for many types of biological analyses. This dissertation describes the fabrication and detection principles for several low-cost optical technologies for mHealth applications including: (1) a webcam based multi-wavelength fluorescence plate reader, (2) a lens-free optical detector used for the detection of Botulinum A neurotoxin activity, (3) a low cost micro-array reader that allows the performance of typical fluorescence based assays demonstrated for the detection of the toxin staphylococcal enterotoxin (SEB), and (4) a wide-field flow cytometer for high throughput detection of fluorescently labeled rare cells. This dissertation discusses how these technologies can be harnessed using readily available consumer electronics components such as webcams, cell phones, CCD cameras, LEDs, and laser diodes. There are challenges in developing devices with sufficient sensitivity and specificity, and approaches are presented to overcoming these challenges to create optical detectors that can serve as low cost medical diagnostics in resource-poor settings for mHealth.

  18. Motion tracking in infrared imaging for quantitative medical diagnostic applications

    PubMed Central

    Cheng, Tze-Yuan; Herman, Cila

    2014-01-01

    In medical applications, infrared (IR) thermography is used to detect and examine the thermal signature of skin abnormalities by quantitatively analyzing skin temperature in steady state conditions or its evolution over time, captured in an image sequence. However, during the image acquisition period, the involuntary movements of the patient are unavoidable, and such movements will undermine the accuracy of temperature measurement for any particular location on the skin. In this study, a tracking approach using a template-based algorithm is proposed, to follow the involuntary motion of the subject in the IR image sequence. The motion tacking will allow to associate a temperature evolution to each spatial location on the body while the body moves relative to the image frame. The affine transformation model is adopted to estimate the motion parameters of the template image. The Lucas–Kanade algorithm is applied to search for the optimized parameters of the affine transformation. A weighting mask is incorporated into the algorithm to ensure its tracking robustness. To evaluate the feasibility of the tracking approach, two sets of IR image sequences with random in-plane motion were tested in our experiments. A steady-state (no heating or cooling) IR image sequence in which the skin temperature is in equilibrium with the environment was considered first. The thermal recovery IR image sequence, acquired when the skin is recovering from 60-s cooling, was the second case analyzed. By proper selection of the template image along with template update, satisfactory tracking results were obtained for both IR image sequences. The achieved tracking accuracies are promising in terms of satisfying the demands imposed by clinical applications of IR thermography. PMID:24587692

  19. Motion tracking in infrared imaging for quantitative medical diagnostic applications

    NASA Astrophysics Data System (ADS)

    Cheng, Tze-Yuan; Herman, Cila

    2014-01-01

    In medical applications, infrared (IR) thermography is used to detect and examine the thermal signature of skin abnormalities by quantitatively analyzing skin temperature in steady state conditions or its evolution over time, captured in an image sequence. However, during the image acquisition period, the involuntary movements of the patient are unavoidable, and such movements will undermine the accuracy of temperature measurement for any particular location on the skin. In this study, a tracking approach using a template-based algorithm is proposed, to follow the involuntary motion of the subject in the IR image sequence. The motion tacking will allow to associate a temperature evolution to each spatial location on the body while the body moves relative to the image frame. The affine transformation model is adopted to estimate the motion parameters of the template image. The Lucas-Kanade algorithm is applied to search for the optimized parameters of the affine transformation. A weighting mask is incorporated into the algorithm to ensure its tracking robustness. To evaluate the feasibility of the tracking approach, two sets of IR image sequences with random in-plane motion were tested in our experiments. A steady-state (no heating or cooling) IR image sequence in which the skin temperature is in equilibrium with the environment was considered first. The thermal recovery IR image sequence, acquired when the skin is recovering from 60-s cooling, was the second case analyzed. By proper selection of the template image along with template update, satisfactory tracking results were obtained for both IR image sequences. The achieved tracking accuracies are promising in terms of satisfying the demands imposed by clinical applications of IR thermography.

  20. Abdominal ultrasound (image)

    MedlinePlus

    Abdominal ultrasound is a scanning technique used to image the interior of the abdomen. Like the X-ray, MRI, ... it has its place as a diagnostic tool. Ultrasound scans use high frequency sound waves to produce ...

  1. Smart Ultrasound Remote Guidance Experiment (SURGE) Preliminary Findings

    NASA Technical Reports Server (NTRS)

    Hurst, Victor; Dulchavsky, Scott; Garcia, Kathleen; Sargsyan, Ashot; Ebert, Doug

    2009-01-01

    To date, diagnostic quality ultrasound images were obtained aboard the International Space Station (ISS) using the ultrasound of the Human Research Facility (HRF) rack in the Laboratory module. Through the Advanced Diagnostic Ultrasound in Microgravity (ADUM) and the Braslet-M Occlusion Cuffs (BRASLET SDTO) studies, non-expert ultrasound operators aboard the ISS have performed cardiac, thoracic, abdominal, vascular, ocular, and musculoskeletal ultrasound assessments using remote guidance from ground-based ultrasound experts. With exploration class missions to the lunar and Martian surfaces on the horizon, crew medical officers will necessarily need to operate with greater autonomy given communication delays (round trip times of up to 5 seconds for the Moon and 90 minutes for Mars) and longer periods of communication blackouts (due to orbital constraints of communication assets). The SURGE project explored the feasibility and training requirements of having non-expert ultrasound operators perform autonomous ultrasound assessments in a simulated exploration mission outpost. The project aimed to identify experience, training, and human factors requirements for crew medical officers to perform autonomous ultrasonography. All of these aims pertained to the following risks from the NASA Bioastronautics Road Map: 1) Risk 18: Major Illness and Trauna; 2) Risk 20) Ambulatory Care; 3) Risk 22: Medical Informatics, Technologies, and Support Systems; and 4) Risk 23: Medical Skill Training and Maintenance.

  2. Diagnostic accuracy of integrated intravascular ultrasound and optical coherence tomography (IVUS-OCT) system for coronary plaque characterization

    NASA Astrophysics Data System (ADS)

    Li, Jiawen; Ma, Teng; Mohar, Dilbahar; Correa, Adrian; Minami, Hataka; Jing, Joseph; Zhou, Qifa; Patel, Pranav M.; Chen, Zhongping

    2014-03-01

    Intravascular ultrasound (IVUS) imaging and optical coherence tomography (OCT), two commonly used intracoronary imaging modalities, play important roles in plaque evaluation. The combined use of IVUS (to visualize the entire plaque volume) and OCT (to quantify the thickness of the plaque cap, if any) is hypothesized to increase plaque diagnostic accuracy. Our group has developed a fully-integrated dual-modality IVUS-OCT imaging system and 3.6F catheter for simultaneous IVUS-OCT imaging with a high resolution and deep penetration depth. However, the diagnostic accuracy of an integrated IVUS-OCT system has not been investigated. In this study, we imaged 175 coronary artery sites (241 regions of interest) from 20 cadavers using our previous reported integrated IVUS-OCT system. IVUS-OCT images were read by two skilled interventional cardiologists. Each region of interest was classified as either calcification, lipid pool or fibrosis. Comparing the diagnosis by cardiologists using IVUSOCT images with the diagnosis by the pathologist, we calculated the sensitivity and specificity for characterization of calcification, lipid pool or fibrosis with this integrated system. In vitro imaging of cadaver coronary specimens demonstrated the complementary nature of these two modalities for plaques classification. A higher accuracy was shown than using a single modality alone.

  3. Diagnostic Laparoscopy with Ultrasound Still Has a Role in the Staging of Pancreatic Cancer: A Systematic Review of the Literature

    PubMed Central

    Levy, Jordan; Tahiri, Mehdi; Vanounou, Tsafrir; Maimon, Geva; Bergman, Simon

    2016-01-01

    Background. The reported incidence of noncurative laparotomies for pancreatic cancer using standard imaging (SI) techniques for staging remains high. The objectives of this study are to determine the diagnostic accuracy of diagnostic laparoscopy with ultrasound (DLUS) in assessing resectability of pancreatic tumors. Study Design. We systematically searched the literature for prospective studies investigating the accuracy of DLUS in determining resectability of pancreatic tumors. Results. 104 studies were initially identified and 19 prospective studies (1,573 patients) were included. DLUS correctly predicted resectability in 79% compared to 55% for SI. DLUS prevented noncurative laparotomies in 33%. Of those, the most frequent DLUS findings precluding resection were liver metastases, vascular involvement, and peritoneal metastases. DLUS had a morbidity rate of 0.8% with no mortalities. DLUS remained superior to SI when analyzing studies published only in the last five years (100% versus 81%), enrolling patients after the year 2000 (74% versus 58%), or comparing DLUS to modern multidimensional CT (100% versus 78%). Conclusion. DLUS seems to still have a role in the preoperative staging of pancreatic cancer. With its ability to detect liver metastases, vascular involvement, and peritoneal metastases, the use of DLUS leads to less noncurative laparotomies. PMID:27122655

  4. SMS-Based Medical Diagnostic Telemetry Data Transmission Protocol for Medical Sensors

    PubMed Central

    Townsend, Ben; Abawajy, Jemal; Kim, Tai-Hoon

    2011-01-01

    People with special medical monitoring needs can, these days, be sent home and remotely monitored through the use of data logging medical sensors and a transmission base-station. While this can improve quality of life by allowing the patient to spend most of their time at home, most current technologies rely on hardwired landline technology or expensive mobile data transmissions to transmit data to a medical facility. The aim of this paper is to investigate and develop an approach to increase the freedom of a monitored patient and decrease costs by utilising mobile technologies and SMS messaging to transmit data from patient to medico. To this end, we evaluated the capabilities of SMS and propose a generic communications protocol which can work within the constraints of the SMS format, but provide the necessary redundancy and robustness to be used for the transmission of non-critical medical telemetry from data logging medical sensors. PMID:22163845

  5. Formal Art Observation Training Improves Medical Students’ Visual Diagnostic Skills

    PubMed Central

    Naghshineh, Sheila; Hafler, Janet P.; Miller, Alexa R.; Blanco, Maria A.; Lipsitz, Stuart R.; Dubroff, Rachel P.; Khoshbin, Shahram

    2008-01-01

    Background Despite evidence of inadequate physical examination skills among medical students, teaching these skills has declined. One method of enhancing inspection skills is teaching “visual literacy,” the ability to reason physiology and pathophysiology from careful and unbiased observation. Objective To improve students’ visual acumen through structured observation of artworks, understanding of fine arts concepts and applying these skills to patient care. Design Prospective, partially randomized pre- vs. post-course evaluation using mixed-methods data analysis. Participants Twenty-four pre-clinical student participants were compared to 34 classmates at a similar stage of training. Intervention Training the Eye: Improving the Art of Physical Diagnosis consists of eight paired sessions of art observation exercises with didactics that integrate fine arts concepts with physical diagnosis topics and an elective life drawing session. Measurements The frequency of accurate observations on a 1-h visual skills examination was used to evaluate pre- vs. post-course descriptions of patient photographs and art imagery. Content analysis was used to identify thematic categories. All assessments were blinded to study group and pre- vs. post-course evaluation. Results Following the course, class participants increased their total mean number of observations compared to controls (5.41 ± 0.63 vs. 0.36 ± 0.53, p < 0.0001) and had increased sophistication in their descriptions of artistic and clinical imagery. A ‘dose-response’ was found for those who attended eight or more sessions, compared to participants who attended seven or fewer sessions (6.31 + 0.81 and 2.76 + 1.2, respectively, p = 0.03). Conclusions This interdisciplinary course improved participants’ capacity to make accurate observations of art and physical findings. Electronic supplementary material The online version of this article (doi:10.1007/s11606-008-0667-0) contains

  6. Development and characterization of hollow polymeric microcapsules for use as contrast agents for diagnostic ultrasound

    NASA Astrophysics Data System (ADS)

    Narayan, Padma Jyothi

    1999-09-01

    This thesis concerns the development and characterization of a new type of rigid-shelled ultrasound contrast agent. A novel method was devised for producing hollow, gas- filled, polymer microcapsules, sized to less than 10 μm in diameter for contrast imaging. This method involved the encapsulation of a solid, volatile core material, and its subsequent evacuation by sublimation. The biodegradable polymer, 50/50 poly(D,L-lactide-co- glycolide), was the main focus of this study. Polymer- based contrast agents have many advantages, such as their applicability for concomitant imaging and drug delivery. Three encapsulation techniques were evaluated: solvent evaporation, coacervation, and spray drying. The polymer molecular weight and polydispersity in the solvent evaporation and coacervation techniques strongly affected microcapsule size and morphology. Efficient mechanical agitation and shear were crucial for obtaining high yields in the desired size range (less than 6 μm). In spray drying, a factorial design approach was used to optimize conditions to produce microcapsules. The main factors affecting spray drying were found to be the temperature driving force for drying and initial polymer concentration. The smallest microcapsule mean diameters were produced by spray drying (3-4 μm) and solvent evaporation (5-6 μm). Zeta potential (ζ) studies for all microcapsule types indicated that the encapsulation technique affected their surface properties due to the orientation of the polymer chains within nascent polymer droplets. Microcapsules with the most hydrophilic tendency were produced with solvent evaporation (ζ ~ -50 mV). In vitro acoustic testing revealed that the 20-41 μm size fractions of coacervate microcapsules were the most echogenic. In vivo ultrasound studies with both solvent evaporation and coacervate microcapsules showed visible enhancement of the color Doppler image in the rabbit kidney for the samples less than 10 μm in diameter. A mathematical

  7. Utilization of diagnostic ultrasound and intravenous lipid-encapsulated perfluorocarbons in non-invasive targeted cardiovascular therapeutics.

    PubMed

    Porter, Thomas R; Choudhury, Songita A; Xie, Feng

    2016-01-01

    Diagnostic ultrasound (DUS) pressures have the ability to induce inertial cavitation (IC) of systemically administered microbubbles; this bioeffect has many diagnostic and therapeutic implications in cardiovascular care. Diagnostically, commercially available lipid-encapsulated perfluorocarbons (LEP) can be utilized to improve endocardial and vascular border delineation as well as assess myocardial perfusion. Therapeutically, the liquid jets induced by IC can alter endothelial function and dissolve thrombi within the immediate vicinity of the cavitating microbubbles. The cavitating LEP can also result in the localized release of any bound therapeutic substance at the site of insonation. DUS-induced IC has been tested in pre-clinical studies to determine what effect it has on acute vascular and microvascular thrombosis as well as nitric oxide (NO) release. These pre-clinical studies have consistently shown that DUS-induced IC of LEP is effective in restoring coronary vascular and microvascular flow in acute ST segment elevation myocardial infarction (STEMI), with microvascular flow improving even if upstream large vessel flow has not been achieved. The initial clinical trials examining the efficacy of short pulse duration DUS high mechanical index impulses in patients with STEMI are underway, and preliminary studies have suggested that earlier epicardial vessel recanalization can be achieved prior to arriving in the cardiac catheterization laboratory. DUS high mechanical index impulses have also been effective in pre-clinical studies for targeting DNA delivery that has restored islet cell function in type I diabetes and restored vascular flow in the extremities downstream from a peripheral vascular occlusion. Improvements in this technique will come from three dimensional arrays for therapeutic applications, more automated delivery techniques that can be applied in the field, and use of submicron-sized acoustically activated LEP droplets that may better permeate the

  8. Droplets, Bubbles and Ultrasound Interactions.

    PubMed

    Shpak, Oleksandr; Verweij, Martin; de Jong, Nico; Versluis, Michel

    2016-01-01

    The interaction of droplets and bubbles with ultrasound has been studied extensively in the last 25 years. Microbubbles are broadly used in diagnostic and therapeutic medical applications, for instance, as ultrasound contrast agents. They have a similar size as red blood cells, and thus are able to circulate within blood vessels. Perfluorocarbon liquid droplets can be a potential new generation of microbubble agents as ultrasound can trigger their conversion into gas bubbles. Prior to activation, they are at least five times smaller in diameter than the resulting bubbles. Together with the violent nature of the phase-transition, the droplets can be used for local drug delivery, embolotherapy, HIFU enhancement and tumor imaging. Here we explain the basics of bubble dynamics, described by the Rayleigh-Plesset equation, bubble resonance frequency, damping and quality factor. We show the elegant calculation of the above characteristics for the case of small amplitude oscillations by linearizing the equations. The effect and importance of a bubble coating and effective surface tension are also discussed. We give the main characteristics of the power spectrum of bubble oscillations. Preceding bubble dynamics, ultrasound propagation is introduced. We explain the speed of sound, nonlinearity and attenuation terms. We examine bubble ultrasound scattering and how it depends on the wave-shape of the incident wave. Finally, we introduce droplet interaction with ultrasound. We elucidate the ultrasound-focusing concept within a droplets sphere, droplet shaking due to media compressibility and droplet phase-conversion dynamics. PMID:26486337

  9. The analysis of in-air reverberation patterns from medical ultrasound transducers

    PubMed Central

    Quinn, T

    2014-01-01

    National guidelines for routine ultrasound quality assurance include the measurement of transducer sensitivity using the in-air reverberation pattern generated from a transducer operating in air. The in-air reverberation method has been compared with other well-known measures of transducer sensitivity, such as the Sonora FirstCall probe tester (Sonora Medical Systems Inc, Longmont, CO, USA) and phantom-based images. There is good agreement between the in-air reverberation images and the Sonora FirstCall probe data for individual crystal sensitivity. However, the in-air reverberation approach is cheaper and easier to implement for linear and curvilinear transducers. The methods used for measuring the in-air reverberation pattern and the influence of scanner parameters such as gain and output power have been investigated. In general, reliance on a visual assessment of reverberation depth can lead to inconsistencies in the measurement of reverberation depth, when taken over a period of several months. The value of scanner parameters, in particular scanner gain, is also important when trying to measure changes in reverberation depth due to changes in transducer performance. A more accurate assessment of changes in transducer sensitivity, using the in-air reverberation method, is found by measuring the peak pixel grey scale values within a chosen reverberation band in the image. This quantitative approach can be taken a step further by assessing changes within the whole in-air reverberation pattern, by applying a two-dimensional cross correlation between two reverberation images to assess changes in transducer performance. PMID:27433190

  10. Children’s Exposure to Diagnostic Medical Radiation and Cancer Risk: Epidemiologic and Dosimetric Considerations

    PubMed Central

    Linet, Martha S.; Kim, Kwang pyo; Rajaraman, Preetha

    2009-01-01

    While the etiology of most childhood cancers is largely unknown, epidemiologic studies have consistently found an association between exposure to medical radiation during pregnancy and risk of childhood cancer in offspring. The relation between early life diagnostic radiation exposure and occurrence of pediatric cancer risks is less clear. This review summarizes current and historical estimated doses for common diagnostic radiologic procedures as well as the epidemiologic literature on the role of maternal prenatal, children’s postnatal and parental preconception diagnostic radiologic procedures on subsequent risk of childhood malignancies Risk estimates are presented according to factors such as the year of birth of the child, trimester and medical indication for the procedure, and the number of films taken. The paper also discusses limitations of the methods employed in epidemiologic studies to assess pediatric cancer risks, the effects on clinical practice of the results reported from the epidemiologic studies, and clinical and public health policy implications of the findings. Gaps in understanding and additional research needs are identified. Important research priorities include nationwide surveys to estimate fetal and childhood radiation doses from common diagnostic procedures, and epidemiologic studies to quantify pediatric and lifetime cancer risks from prenatal and early childhood exposures to diagnostic radiography, computed tomography, and fluoroscopically-guided procedures. PMID:19083224

  11. Duplex ultrasound

    MedlinePlus

    Vascular ultrasound; Peripheral vascular ultrasound ... A duplex ultrasound combines traditional ultrasound with Doppler ultrasound . Traditional ultrasound uses sound waves that bounce off blood vessels to create ...

  12. Diagnostic accuracy of ovarian cyst segmentation in B-mode ultrasound images

    NASA Astrophysics Data System (ADS)

    Bibicu, Dorin; Moraru, Luminita; Stratulat (Visan), Mirela

    2013-11-01

    Cystic and polycystic ovary syndrome is an endocrine disorder affecting women in the fertile age. The Moore Neighbor Contour, Watershed Method, Active Contour Models, and a recent method based on Active Contour Model with Selective Binary and Gaussian Filtering Regularized Level Set (ACM&SBGFRLS) techniques were used in this paper to detect the border of the ovarian cyst from echography images. In order to analyze the efficiency of the segmentation an original computer aided software application developed in MATLAB was proposed. The results of the segmentation were compared and evaluated against the reference contour manually delineated by a sonography specialist. Both the accuracy and time complexity of the segmentation tasks are investigated. The Fréchet distance (FD) as a similarity measure between two curves and the area error rate (AER) parameter as the difference between the segmented areas are used as estimators of the segmentation accuracy. In this study, the most efficient methods for the segmentation of the ovarian were analyzed cyst. The research was carried out on a set of 34 ultrasound images of the ovarian cyst.

  13. Diagnostic efficacy of color Doppler ultrasound in evaluation of cervical lymphadenopathy

    PubMed Central

    Misra, Deepankar; Panjwani, Sapna; Rai, Shalu; Misra, Akansha; Prabhat, Mukul; Gupta, Prashant; Talukder, Subrata K.

    2016-01-01

    Background: To evaluate the efficacy of color Doppler ultrasound (CDUS) in differentiating benign and malignant cervical lymph nodes by detecting differences in blood flow patterns. Materials and Methods: In this cross-sectional prospective study, 25 untreated patients with clinical evidence of cervical lymphadenopathy were evaluated. CDUS was performed for 80 cervical lymph nodes. The gray scale parameters of the lymph node and intranodal perfusion sites were the key CDUS features used to differentiate between reactive and metastatic lymph nodes. Histopathological confirmations were obtained and compared with the results of CDUS. Results: Initially, 53 cervical lymph nodes were evaluated by clinical examination. Twenty-seven additional lymph nodes (53 + 27 = 80) were discovered by CDUS evaluation. Gray scale parameters for lymph nodes such as size of lymph node, shape of lymph node, and presence or absence of hilum revealed highly significant results (P < 0.0001). Color Doppler flow signals revealed that central/hilar flow was characteristic for benign nodes whereas peripheral/mixed flow was characteristic for malignant nodes, the findings were highly significant (P < 0.0001). Gray scale and color Doppler features are used to differentiate benign and malignant nodes. Conclusion: Within the limitations of this study, CDUS evaluation was found to be highly significant with a high sensitivity and specificity over clinical evaluation CDUS examination provides a prospect to reduce the need for biopsy/fine needle aspiration cytology in reactive nodes. PMID:27274341

  14. Examining shifts in medical students' microanalytic motivation beliefs and regulatory processes during a diagnostic reasoning task.

    PubMed

    Cleary, Timothy J; Dong, Ting; Artino, Anthony R

    2015-08-01

    This study examined within-group shifts in the motivation beliefs and regulatory processes of second-year medical students as they engaged in a diagnostic reasoning activity. Using a contextualized assessment methodology called self-regulated learning microanalysis, the authors found that the 71 medical student participants showed statistically significant and relatively robust declines in their self-efficacy beliefs and strategic regulatory processes following negative feedback about their performance on the diagnostic reasoning task. Descriptive statistics revealed that changes in strategic thinking following negative corrective feedback were most characterized by shifts away from task-specific processes (e.g., integration, differentiating diagnoses) to non-task related factors. Implications and areas for future research are presented and discussed. PMID:25209963

  15. Principles and applications of polymerase chain reaction in medical diagnostic fields: a review

    PubMed Central

    Valones, Marcela Agne Alves; Guimarães, Rafael Lima; Brandão, Lucas André Cavalcanti; de Souza, Paulo Roberto Eleutério; de Albuquerque Tavares Carvalho, Alessandra; Crovela, Sergio

    2009-01-01

    Recent developments in molecular methods have revolutionized the detection and characterization of microorganisms in a broad range of medical diagnostic fields, including virology, mycology, parasitology, microbiology and dentistry. Among these methods, Polymerase Chain Reaction (PCR) has generated great benefits and allowed scientific advancements. PCR is an excellent technique for the rapid detection of pathogens, including those difficult to culture. Along with conventional PCR techniques, Real-Time PCR has emerged as a technological innovation and is playing an ever-increasing role in clinical diagnostics and research laboratories. Due to its capacity to generate both qualitative and quantitative results, Real-Time PCR is considered a fast and accurate platform. The aim of the present literature review is to explore the clinical usefulness and potential of both conventional PCR and Real-Time PCR assays in diverse medical fields, addressing its main uses and advances. PMID:24031310

  16. Qualitative differences in knowledge structure are associated with diagnostic performance in medical students.

    PubMed

    Coderre, Sylvain; Jenkins, Deirdre; McLaughlin, Kevin

    2009-12-01

    Diagnosing is a knowledge-based skill: to diagnose one must retrieve knowledge from long-term memory and then apply this to a new clinical problem. Prior research on expertise found differences in knowledge structure between experts and novices, and it is assumed that the superior diagnostic performance of experts is somehow related to their superior knowledge structure. Here our objective was to study knowledge structure in final year medical students and to examine the association between knowledge structure and diagnostic performance. Ninety-one students participated. We used concept sorting to assess knowledge structures for four clinical problems. We performed qualitative analysis of knowledge structures, categorizing these as either problem-specific, where knowledge was predominantly structured around concepts specific to that clinical problem, or generic, where knowledge was structured around general concepts that could apply to all clinical problems. We evaluated diagnostic performance using problem-solving questions. Knowledge structure varied between different problems, but for each problem most students had problem-specific knowledge structure. These students had better diagnostic performance than those with generic structure (68.5 vs. 55.3%, d = 0.45, P = 0.004). This difference persisted after adjusting for overall medical knowledge (performance on the Medical Council of Canada Part 1 examination) and clinical problem. We found that most students organize their knowledge around problem-specific concepts, and that this type of knowledge was associated with better diagnostic performance. This may be due to easier knowledge retrieval if there is congruence between how knowledge is stored and how it is applied when diagnosing. PMID:19107567

  17. Evaluation of the diagnostic utility of endobronchial ultrasound-guided transbronchial needle aspiration for metastatic mediastinal tumors

    PubMed Central

    Dziedzic, Dariusz; Peryt, Adam; Szolkowska, Malgorzata; Langfort, Renata; Orlowski, Tadeusz

    2016-01-01

    Background and Objectives: The mediastinum is a relatively uncommon site of distant metastases, which typically appear as peripheral lung nodules. We chose to assess the utility of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for the diagnosis of distant metastases to the mediastinum. Materials and Methods: Over the period 2008–2013, a total of 446 patients with concurrent or previously diagnosed and treated extrathoracic malignancies were evaluated. Results: Surgical treatment was carried out in 414 patients (156 women and 237 men aged 26–68 years, mean age of 56.5 years) presenting with distant metastases to the lungs: Thoracoscopic wedge resection was completed in 393 patients and lobectomy and segmentectomy were performed in 7 and 14 patients, respectively. The median time from primary tumor resection was 6.5 years (range: 4.5 months to 17 years). Thirty-two of these patients underwent EBUS-TBNA for mediastinal manifestation of the underlying disease. EBUS-TBNA specimens were aspirated from the subcarinal or right paratracheal lymph node stations in 26 (81%) patients and from the hilar lymph nodes in 6 (18.8%) patients only. Metastases to lymph nodes were confirmed in 14 of these patients (43.8%). Primary lung cancer was diagnosed in seven patients. Mediastinoscopy was performed in two patients to reveal either lymph node metastasis or sarcoidosis. Thoracotomy for pulmonary metastases resection and mediastinal lymph node biopsy was performed in nine patients. Lymph node metastasis was confirmed in five patients (15.6%). The diagnostic efficacy, sensitivity, specificity, and negative predictive value (NPV) of EBUS-TBNA were 78.8%, 93.3%, 100%, and 87.5%, respectively. Conclusion: EBUS-TBNA is a valuable diagnostic tool in a selected group of patients with secondary tumors in the mediastinum and lungs. PMID:27386474

  18. Diagnostic value of CT compared to ultrasound in the evaluation of acute abdominal pain in children younger than 10 years old.

    PubMed

    Simanovsky, Natalia; Dola, Tamar; Hiller, Nurith

    2016-02-01

    To assess the diagnostic value of ultrasound compared to CT in evaluating acute abdominal pain of different causes in children 10 years of age and under, hospital records and imaging files of 4052 patients under age of 10 who had imaging for abdominal pain were reviewed. One-hundred-thirty-two patients (3 %), (74 males/58 females) who underwent ultrasound and CT within 24 h were divided by age: group I, ages 0-48 months (25 patients); group II, 49-84 months (53 patients); and group III, 85-120 months (54 patients). Diagnoses at ultrasound, CT, and discharge were compared. Cases of a change in diagnosis following CT and impact of the changed diagnosis on patient management were assessed. Non-diagnostic ultrasound or a diagnostic conundrum was present in a small percentage (3 %) of our patients. In the group of patients imaged with two modalities, CT changed the diagnosis in 73/132 patients (55.3 %). Patient management changed in 63/132 patients (47.7 %). CT changed the diagnosis in 46/64 patients with surgical conditions (71.8 %, p < 0.001). Among patients with surgical conditions, the difference between ultrasonography (US) and CT diagnoses was significant in groups 2 (p = 0.046) and 3 (p =  .001). The impact of the change in diagnosis in surgical patients imaged with two modalities was significant in the group as a whole and in each age group separately. Non-diagnostic or equivocal US in a small percentage of patients is probably sufficient to justify the additional radiation burden. PMID:26453370

  19. Anesthetic Techniques Influence the Induction of Pulmonary Capillary Hemorrhage During Diagnostic Ultrasound Scanning in Rats

    PubMed Central

    Miller, Douglas L.; Dou, Chunyan; Raghavendran, Krishnan

    2015-01-01

    Objectives Puhnonary apillary hemorrhage can be induced by diagnostic ultrasonnd (US) during direct pulmonary US scanning in rats. The influence of specific anesthetic tedmiques on this bioeffect was examined. Methods Ketamine plus xylazine has been used previously. In this study, the influence of intraperitoneal injections of ketamine and pentobarbital, inhalational isoflurane, and the supplemental use of xylazine with ketamine and isollurane was tested. A diagnostic US machine with a7.6-MHz linear array was used to image the right lung of anesthetized rats in a warmed water bath at different mechanical index (MI) settings. Pulmonary capillary hemorrhage was assessed by measuring comet tail artifacts in the image and by morphometry of the hemorrhagic areas on excised lungs. Results Pulmonary capillary hemorrhage was greatest for pentobarbital, lower for inhalational isoflurane, and lowest for ketamine anesthesia, with occurrence thresholds at at Mis of about 0.44, 0.8, and 0.8, respectively. Addition of xylazine produced a substantial increaseinhemorrhageanda significant proportion of hemorrhage occurrence for ketamineat an MI of 0.7 (P < .01) and forisofluraneat an MI of 0.52 (P < .01). Conclusions Ketamine plus xylazine and pentobarbital yield lower thresholds than ketamine or isoflurane alone by nearly a factor of 2 in MI. These results suggest that the choice of the anesthetic agent substantially modifies the relative risks of pulmonary capillary hemorrhage from pulmonary US. PMID:25614402

  20. The Diagnostic Accuracy of Linear Endoscopic Ultrasound for Evaluating Symptoms Suggestive of Common Bile Duct Stones.

    PubMed

    Wang, Min; He, Xu; Tian, Chuan; Li, Jian; Min, Feng; Li, Hong-Yan

    2016-01-01

    Background. In order to assess the diagnostic accuracy of linear EUS for evaluating clinically suggestive CBD stones in high-risk groups. Methods. 202 patients with clinically suggestive CBD stones in high-risk groups who underwent linear EUS examination between January 2012 and January 2015 were retrospectively reviewed. Endoscopic retrograde cholangiopancreatography (ERCP) with stone extraction or surgical choledochoscopy was only performed when a CBD stone was detected by linear EUS. Cases that were negative for CBD stones were followed up for at least 6 months. Results. Of 202 enrolled patients, 126 were positive for CBD stones according to linear EUS findings. 124 patients successfully underwent ERCP, and ERCP failed in 2 who were later successfully treated by surgical intervention. There were 2 false-positive cases with positive findings for CBD stones on ERCP. Among 76 patients without CBD stones, no false-negative cases were identified during the mean 6-month follow-up. Linear EUS had sensitivity, specificity, and positive and negative predictive values for the detection of CBD stones of 100%, 92.88%, 98.21%, and 100%, respectively. Conclusions. Linear EUS is a safe and efficacious diagnostic tool for evaluating clinically suggestive CBD stones with high risk of choledocholithiasis. Performing linear EUS prior to ERCP in patients with symptoms suggestive of CBD stones can reduce unnecessary ERCP procedures. PMID:27610131

  1. The Diagnostic Accuracy of Linear Endoscopic Ultrasound for Evaluating Symptoms Suggestive of Common Bile Duct Stones

    PubMed Central

    He, Xu; Li, Jian; Min, Feng; Li, Hong-yan

    2016-01-01

    Background. In order to assess the diagnostic accuracy of linear EUS for evaluating clinically suggestive CBD stones in high-risk groups. Methods. 202 patients with clinically suggestive CBD stones in high-risk groups who underwent linear EUS examination between January 2012 and January 2015 were retrospectively reviewed. Endoscopic retrograde cholangiopancreatography (ERCP) with stone extraction or surgical choledochoscopy was only performed when a CBD stone was detected by linear EUS. Cases that were negative for CBD stones were followed up for at least 6 months. Results. Of 202 enrolled patients, 126 were positive for CBD stones according to linear EUS findings. 124 patients successfully underwent ERCP, and ERCP failed in 2 who were later successfully treated by surgical intervention. There were 2 false-positive cases with positive findings for CBD stones on ERCP. Among 76 patients without CBD stones, no false-negative cases were identified during the mean 6-month follow-up. Linear EUS had sensitivity, specificity, and positive and negative predictive values for the detection of CBD stones of 100%, 92.88%, 98.21%, and 100%, respectively. Conclusions. Linear EUS is a safe and efficacious diagnostic tool for evaluating clinically suggestive CBD stones with high risk of choledocholithiasis. Performing linear EUS prior to ERCP in patients with symptoms suggestive of CBD stones can reduce unnecessary ERCP procedures. PMID:27610131

  2. Evaluation of Diagnostic Efficiency of Ultrasound Features on Malignant Thyroid Nodules in Chinese Patients

    PubMed Central

    Li, Ru-Qiang; Yuan, Ge-Heng; Chen, Ming; Shao, Yi-Min; Zhu, Sai-Nan; Zhang, Jun-Qing; Guo, Xiao-Hui

    2016-01-01

    Background: The aim of this study was to evaluate the efficacy of ultrasonic features in predicting the malignancy of thyroid nodules in a group of Chinese patients. Methods: In all, 762 patients with thyroid nodules (424 malignant and 338 benign) underwent ultrasound (US) check and surgery between March 2011 and July 2014 at Peking University First Hospital were identified. Univariate and receiver operating characteristic (ROC) analyses were performed to calculate the sensitivity, specificity, negative and positive predictive values of each US feature, and the accuracy of their combinations for prediction of malignancy. Results: Patients with malignant nodules were younger and without obvious risk history than those in the benign group (P < 0.001, P = 0.93). No individual US sign was fully predictive of a malignant lesion. The Youden indexes of irregular margins and hypoechogenicity were the first and second highest in all US features, which were 51.9% and 45.2%, respectively. The sensitivity of solid components (89.7%) and hypoechogenicity (89.2%) and the specificity of taller-than-wide shape (98.5%) and microcalcifications (90.6%) were the first and second highest in all US features. Intranodular flow on a color Doppler examination was a weak predictor of malignancy. Under ROC analysis excepting intranodular flow, the 95% confidence interval (CI) of areas under the curves of hypoechogenicity and irregular margins with any one of the US features were overlapped that of five-feature combinations (95% CI: 0.850–0.901). Conclusions: We should be alert with taller-than-wide shape and microcalcifications. Intranodular flow was a weak predictor of malignancy. According to Youden indexes and ROC analysis, irregular margins and hypoechogenicity combined with solid component or taller-than-wide shapes or microcalcifications have a high predicative value for malignant thyroid nodules in Chinese patients. PMID:27453225

  3. Diagnostic Yield of Fine-Needle Aspiration for Axillary Lymph Nodes During Screening Breast Ultrasound.

    PubMed

    Youn, Inyoung; Kim, Eun-Kyung; Yoon, Jung Hyun; Moon, Hee Jung; Kim, Min Jung

    2016-06-01

    The purpose of our study was to assess the positive predictive value (PPV) of ultrasound (US)-guided fine-needle aspiration (FNA) and the cancer detection rate for incidentally detected abnormal axillary lymph node (LN) in patients who underwent screening US. We retrospectively reviewed 72 LNs of 69 patients (mean age, 44.9 years) who underwent US-FNA for incidentally detected abnormal axillary LNs on 50,488 screening US from January 2005 to December 2011. The PPV of US-FNA and the cancer detection rate were calculated. We evaluated US images for lymph node size, abnormal findings (hilum loss, eccentric cortical thickening, round shape, extranodal extension, or marked hypoechoic cortex), and mammography for the identification of abnormal LNs. The PPV of each finding was also calculated. The PPV of US-FNA and the cancer detection rate were 2.8% (2/72) and 0.004% (2/50,488), respectively. The mean (SD) measurements for long-axis, short-axis, and cortical thickening of the LNs were 14.9 (5.9) mm, 8.5 (3.5) mm, and 5.8 (2.8) mm, respectively. Of the positive LNs, US findings of hilum loss, eccentric cortical thickening, and extranodal extension were found, and each corresponding PPV was 6.3% (1/16), 1.8% (1/56), and 14.3% (1/7), respectively. The PPV of mammography was 14.3% (1/7). Our results suggest that the PPVs of US-FNA and the cancer detection rate for incidentally detected abnormal axillary LNs during screening US are too low to recommend axillary US during breast US screening and that follow-up is acceptable for abnormal LNs detected during screening breast US that do not have extranodal extension or are negative on mammography. PMID:27054655

  4. Design of a Global Medical Database which is Searchable by Human Diagnostic Patterns

    PubMed Central

    Orthuber, Wolfgang; Fiedler, Gunar; Kattan, Michael; Sommer, Thorsten; Fischer-Brandies, Helge

    2008-01-01

    We describe a global medical database which is designed for efficient evaluation. It allows language independent search for human diagnostic parameters. Core of the database is a fully automated electronic archive and distribution server for medical histories of real but anonymous patients which contain patterns of diagnosis, chosen treatment, and outcome. Every pattern is represented by a feature vector which is usually a sequence of numbers, and labeled by an unambiguous "pattern name" which identifies its meaning. Similarity search is always done only over patterns with the same pattern name, because these are directly comparable. Similarities of patterns are mapped to spatial similarities (small distances) of their feature vectors using an appropriate metric. This makes them searchable. Pattern names can be "owned" like today domain names. This facilitates unbureaucratic definition of patterns e.g. by manufacturers of diagnostic devices. Application: If there is a new patient with certain diagnostic patterns, it is possible to combine a part or all of them and to search in the database for completed histories of patients with similar patterns to find the best treatment. Confinement of the result by conventional language based search terms is possible, and immediate individual statistics or regression analyses can quantify probabilities of success in case of different treatment choices. Conclusions: Efficient searching with diagnostic patterns is technically feasible. Labeled feature vectors induce a systematic and expandable approach. The database also allows immediate calculation of individual up to date prediction models. PMID:19415132

  5. Multidimensional, multistage wavelet footprints: a new tool for image segmentation and feature extraction in medical ultrasound

    NASA Astrophysics Data System (ADS)

    Jansen, Christian H. P.; Arigovindan, Muthuvel; Suhling, Michael; Marsch, Stefan; Unser, Michael A.; Hunziker, Patrick

    2003-05-01

    We present a new wavelet-based strategy for autonomous feature extraction and segmentation of cardiac structures in dynamic ultrasound images. Image sequences subjected to a multidimensional (2D plus time) wavelet transform yield a large number of individual subbands, each coding for partial structural and motion information of the ultrasound sequence. We exploited this fact to create an analysis strategy for autonomous analysis of cardiac ultrasound that builds on shape- and motion specific wavelet subband filters. Subband selection was in an automatic manner based on subband statistics. Such a collection of predefined subbands corresponds to the so-called footprint of the target structure and can be used as a multidimensional multiscale filter to detect and localize the target structure in the original ultrasound sequence. Autonomous, unequivocal localization by the autonomous algorithm is then done using a peak finding algorithm, allowing to compare the findings with a reference standard. Image segmentation is then possible using standard region growing operations. To test the feasibility of this multiscale footprint algorithm, we tried to localize, enhance and segment the mitral valve autonomously in 182 non-selected clinical cardiac ultrasound sequences. Correct autonomous localization by the algorithm was feasible in 165 of 182 reconstructed ultrasound sequences, using the experienced echocardiographer as reference. This corresponds to a 91% accuracy of the proposed method in unselected clinical data. Thus, multidimensional multiscale wavelet footprints allow successful autonomous detection and segmentation of the mitral valve with good accuracy in dynamic cardiac ultrasound sequences which are otherwise difficult to analyse due to their high noise level.

  6. A comparison of the diagnostic accuracy of MARS MRI and ultrasound of the painful metal-on-metal hip arthroplasty

    PubMed Central

    Siddiqui, Imran A; Sabah, Shiraz A; Satchithananda, Keshthra; Lim, Adrian K; Cro, Suzie; Henckel, Johann; Skinner, John A

    2014-01-01

    Background and purpose Metal artifact reduction sequence (MARS) MRI and ultrasound scanning (USS) can both be used to detect pseudotumors, abductor muscle atrophy, and tendinous pathology in patients with painful metal-on-metal (MOM) hip arthroplasty. We wanted to determine the diagnostic test characteristics of USS using MARS MRI as a reference for detection of pseudotumors and muscle atrophy. Patients and methods We performed a prospective cohort study to compare MARS MRI and USS findings in 19 consecutive patients with unilateral MOM hips. Protocolized USS was performed by consultant musculoskeletal radiologists who were blinded regarding clinical details. Reports were independently compared with MARS MRI, the imaging gold standard, to calculate predictive values. Results The prevalence of pseudotumors on MARS MRI was 68% (95% CI: 43–87) and on USS it was 53% (CI: 29–76). The sensitivity of USS in detecting pseudotumors was 69% (CI 39–91) and the specificity was 83% (CI: 36–97). The sensitivity of detection of abductor muscle atrophy was 47% (CI: 24–71). In addition, joint effusion was detected in 10 cases by USS and none were seen by MARS MRI. Interpretation We found a poor agreement between USS and MARS MRI. USS was inferior to MARS MRI for detection of pseudotumors and muscle atrophy, but it was superior for detection of joint effusion and tendinous pathologies. MARS MRI is more advantageous than USS for practical reasons, including preoperative planning and longitudinal comparison. PMID:24694273

  7. Medication Adherence in Patients with Rheumatoid Arthritis: The Effect of Patient Education, Health Literacy, and Musculoskeletal Ultrasound

    PubMed Central

    Joplin, Samantha; van der Zwan, Rick; Joshua, Fredrick; Wong, Peter K. K.

    2015-01-01

    Background. Rheumatoid arthritis (RA) is a chronic systemic inflammatory disease affecting <1% of the population. Incompletely controlled RA results in fatigue, joint and soft tissue pain, progressive joint damage, reduced quality of life, and increased cardiovascular mortality. Despite an increasing range of disease modifying agents which halt disease progression, poor patient adherence with medication is a significant barrier to management. Objective. The goal of this review was to examine the effectiveness of measures to improve patient medication adherence. Methods. Studies addressing treatment adherence in patients with RA were identified by trawling PsycINFO, Medline, Cochrane, Pubmed, and ProQuest for studies published between January 2000 and October 2014. Articles were independently reviewed to identify relevant studies. Results. Current strategies were of limited efficacy in improving patient adherence with medications used to treat RA. Conclusion. Poor medication adherence is a complex issue. Low educational levels and limited health literacy are contributory factors. Psychological models may assist in explaining medication nonadherence. Increasing patient knowledge of their disease seems sensible. Existing educational interventions appear ineffective at improving medication adherence, probably due to an overemphasis on provision of biomedical information. A novel approach to patient education using musculoskeletal ultrasound is proposed. PMID:26060812

  8. Abdominal ultrasound

    MedlinePlus

    ... AK, Gillard JH, et al, eds. Grainger & Allison's Diagnostic Radiology: A Textbook of Medical Imaging . 6th ed. New York, NY: Churchill Livingstone; 2014:chap 3. Kim DH, Pickhardt PJ. Diagnostic imaging procedures in gastroenterology. In: Goldman L, Ausiello ...

  9. Design and Control of Functional Microbubbles for Medical Applications of Ultrasound

    NASA Astrophysics Data System (ADS)

    Takagi, Shu; Osaki, Taichi; Ariyoshi, Takuya; Azuma, Takashi; Ichiyanagi, Mitsuhisa; Kinefuchi, Ikuya

    2015-11-01

    Microbubbles are used as a contrast agent for ultrasound diagnosis. It is also expected to be use for the treatment. One of the possible applications is microbubble DDS. For that purpose, microbubbles need to be well-controlled for the generating process and manipulation. In this talk, for the design and control of the functional microbubbles, an experimental study on generation and surface modification of microbubbles are explained. Using a T-junction type microchannel, small bubbles about 5 μm size are successfully generated. For the surface modification, Biotin-coated microbubbles are tried to adhere the Avidin-coated wall. Furthermore, the manipulation of the microbubbles using ultrasound is also discussed. Plane-wave and focused ultrasound is used to manipulate a microbubble and bubble clusters. The experimental results are shown in the presentation. Supported by JSPS KAKENHI Grant Number 15K13865.

  10. Review article: Use of ultrasound in the developing world

    PubMed Central

    2011-01-01

    As portability and durability improve, bedside, clinician-performed ultrasound is seeing increasing use in rural, underdeveloped parts of the world. Physicians, nurses and medical officers have demonstrated the ability to perform and interpret a large variety of ultrasound exams, and a growing body of literature supports the use of point-of-care ultrasound in developing nations. We review, by region, the existing literature in support of ultrasound use in the developing world and training guidelines currently in use, and highlight indications for emergency ultrasound in the developing world. We suggest future directions for bedside ultrasound use and research to improve diagnostic capacity and patient care in the most remote areas of the globe. PMID:22152055

  11. Diagnostic imaging.

    PubMed

    Morris, Peter; Perkins, Alan

    2012-04-21

    Physical techniques have always had a key role in medicine, and the second half of the 20th century in particular saw a revolution in medical diagnostic techniques with the development of key imaging instruments: x-ray imaging and emission tomography (nuclear imaging and PET), MRI, and ultrasound. These techniques use the full width of the electromagnetic spectrum, from gamma rays to radio waves, and sound. In most cases, the development of a medical imaging device was opportunistic; many scientists in physics laboratories were experimenting with simple x-ray images within the first year of the discovery of such rays, the development of the cyclotron and later nuclear reactors created the opportunity for nuclear medicine, and one of the co-inventors of MRI was initially attempting to develop an alternative to x-ray diffraction for the analysis of crystal structures. What all these techniques have in common is the brilliant insight of a few pioneering physical scientists and engineers who had the tenacity to develop their inventions, followed by a series of technical innovations that enabled the full diagnostic potential of these instruments to be realised. In this report, we focus on the key part played by these scientists and engineers and the new imaging instruments and diagnostic procedures that they developed. By bringing the key developments and applications together we hope to show the true legacy of physics and engineering in diagnostic medicine. PMID:22516558

  12. Evaluation of diagnostic utility, safety considerations, and effect on fertility of transvaginal ultrasound-guided ovarian biopsy in mares.

    PubMed

    Diel de Amorim, Mariana; Nairn, Dawne; Manning, Steve; Dedden, Ilse; Ripley, Elinorah; Nielsen, Kayla; Card, Claire

    2016-04-01

    Ultrasound-guided biopsies of corpora lutea have been previously used for research purposes in the mare and cow. However, the health effects and fertility after transvaginal luteal biopsies (TVLB) or transvaginal ovarian biopsies (TVOB) obtained for diagnostic purposes in cases of suspected ovarian tumors have not been previously evaluated in the horse. The aim of this study was to determine the effects on health and fertility of TVLB and TVOB in mares; 53 mares were included in the study (11 control non-biopsied mares, 37 TVLB mares biopsied on one or more of the following Days 8, 10, 12, 15, 21, and 5 TVOB mares with ovarian abnormalities), resulting in a total of 108 TVLB and TVOB cycles and 183 procedures. Mares were divided into Groups 1 to 3 by the number of TVLB per estrous cycle (mare in Group 1 had 1 TVLB procedure, mares in Group 2 had 2 TVLB procedures, and mares in Group 3 had 3 TVLB procedures). Group 4 comprised TVOB mare cycles with ovarian abnormalities (n = 5). Mares were examined to determine day of ovulation (Day 0) and the presence of a corpora lutea using transrectal ultrasonography. Mares were sedated, and an ultrasound-guided transvaginal biopsy was performed of luteal or ovarian tissue. Health effects of TVLB or TVOB were assessed by daily rectal temperatures, appetite, and general demeanor for 72 hours post-procedure, and 3 mares were examined at necropsy. Fertility was not significantly different in control and TVLB Groups 1 to 3 (P = 0.7648) and in the first or subsequent cycles where the ovulation was from an ovary that had a previous TVLB (P = 0.7147). A TVLB on Day 8 post-ovulation may induce an early return to estrus. In conclusion, the TVLB or TVOB procedure had no effect on health and fertility in this study if the procedure was correctly performed with good technique. Because of the low number of cycles (n = 37), the fertility data should be interpreted with caution. The TVOB may be applied in the diagnosis of mares with

  13. Diagnostic agreement when comparing still and video imaging for the medical evaluation of child sexual abuse.

    PubMed

    Killough, Emily; Spector, Lisa; Moffatt, Mary; Wiebe, Jan; Nielsen-Parker, Monica; Anderst, Jim

    2016-02-01

    Still photo imaging is often used in medical evaluations of child sexual abuse (CSA) but video imaging may be superior. We aimed to compare still images to videos with respect to diagnostic agreement regarding hymenal deep notches and transections in post-pubertal females. Additionally, we evaluated the role of experience and expertise on agreement. We hypothesized that videos would result in improved diagnostic agreement of multiple evaluators as compared to still photos. This was a prospective quasi-experimental study using imaging modality as the quasi-independent variable. The dependent variable was diagnostic agreement of participants regarding presence/absence of findings indicating penetrative trauma on non-acute post-pubertal genital exams. Participants were medical personnel who regularly perform CSA exams. Diagnostic agreement was evaluated utilizing a retrospective selection of videos and still photos obtained directly from the videos. Videos and still photos were embedded into an on-line survey as sixteen cases. One-hundred sixteen participants completed the study. Participant diagnosis was more likely to agree with study center diagnosis when using video (p<0.01). Use of video resulted in statistically significant changes in diagnosis in four of eight cases. In two cases, the diagnosis of the majority of participants changed from no hymenal transection to transection present. No difference in agreement was found based on experience or expertise. Use of video vs. still images resulted in increased agreement with original examiner and changes in diagnostic impressions in review of CSA exams. Further study is warranted, as video imaging may have significant impacts on diagnosis. PMID:26746111

  14. 4D Ultrasound - Medical Devices for Recent Advances on the Etiology of Cerebral Palsy

    PubMed Central

    Tomasovic, Sanja; Predojevic, Maja

    2011-01-01

    Children cerebral palsy (CCP) encompasses a group of nonprogessive and noninfectious conditions, which cause light, moderate, and severe deviations in neurological development. Diagnosis of CCP is set mostly by the age of 3 years. The fact that a large number of cerebral damage occurs prenatally and the fact that early intervention in cases of neurological damage is successful, prompted some researchers to explore the possibility of detecting neurologically damaged fetus in the uterus. This research was made possible thanks to the development of two-dimensional ultrasound technology in a real time, which enabled the display of the mobility of the fetus. Advancement of the ultrasound technology has enabled the development of 4D ultrasound where a spontaneous fetal movement can be observed almost in a real time. Estimate of the number and quality of spontaneous fetal movements and stitches on the head, the neurology thumb and a high palate were included in the prenatal neurological screening of the fetus. This raises the question, as to does the fetal behavior reflect, (which was revealed in 2D or 4D ultrasound), fetal neurological development in a manner that will allow the detection of the brain damage. PMID:23407920

  15. Automatic segmentation and classification of gestational sac based on mean sac diameter using medical ultrasound image

    NASA Astrophysics Data System (ADS)

    Khazendar, Shan; Farren, Jessica; Al-Assam, Hisham; Sayasneh, Ahmed; Du, Hongbo; Bourne, Tom; Jassim, Sabah A.

    2014-05-01

    Ultrasound is an effective multipurpose imaging modality that has been widely used for monitoring and diagnosing early pregnancy events. Technology developments coupled with wide public acceptance has made ultrasound an ideal tool for better understanding and diagnosing of early pregnancy. The first measurable signs of an early pregnancy are the geometric characteristics of the Gestational Sac (GS). Currently, the size of the GS is manually estimated from ultrasound images. The manual measurement involves multiple subjective decisions, in which dimensions are taken in three planes to establish what is known as Mean Sac Diameter (MSD). The manual measurement results in inter- and intra-observer variations, which may lead to difficulties in diagnosis. This paper proposes a fully automated diagnosis solution to accurately identify miscarriage cases in the first trimester of pregnancy based on automatic quantification of the MSD. Our study shows a strong positive correlation between the manual and the automatic MSD estimations. Our experimental results based on a dataset of 68 ultrasound images illustrate the effectiveness of the proposed scheme in identifying early miscarriage cases with classification accuracies comparable with those of domain experts using K nearest neighbor classifier on automatically estimated MSDs.

  16. Capillary waveguide optrodes: an approach to optical sensing in medical diagnostics

    NASA Astrophysics Data System (ADS)

    Lippitsch, Max E.; Draxler, Sonja; Kieslinger, Dietmar; Lehmann, Hartmut; Weigl, Bernhard H.

    1996-07-01

    Glass capillaries with a chemically sensitive coating on the inner surface are used as optical sensors for medical diagnostics. A capillary simultaneously serves as a sample compartment, a sensor element, and an inhomogeneous optical waveguide. Various detection schemes based on absorption, fluorescence intensity, or fluorescence lifetime are described. In absorption-based capillary waveguide optrodes the absorption in the sensor layer is analyte dependent; hence light transmission along the inhomogeneous waveguiding structure formed by the capillary wall and the sensing layer is a function of the analyte concentration. Similarly, in fluorescence-based capillary optrodes the fluorescence intensity or the fluorescence lifetime of an indicator dye fixed in the sensing layer is analyte dependent; thus the specific property of fluorescent light excited in the sensing layer and thereafter guided along the inhomogeneous waveguiding structure is a function of the analyte concentration. Both schemes are experimentally demonstrated, one with carbon dioxide as the analyte and the other one with oxygen. The device combines optical sensors with the standard glass capillaries usually applied to gather blood drops from fingertips, to yield a versatile diagnostic instrument, integrating the sample compartment, the optical sensor, and the light-collecting optics into a single piece. This ensures enhanced sensor performance as well as improved handling compared with other sensors. waveguide, blood gases, medical diagnostics.

  17. Medical thoracoscopy: Analysis on diagnostic yield through 30 years of experience

    PubMed Central

    Valsecchi, Alberto; Arondi, Sabrina; Marchetti, Giampietro

    2016-01-01

    BACKGROUND: Medical thoracoscopy (MT) or pleuroscopy is a procedure performed to diagnose and treat malignant and benign pleural diseases. Totally 2752 pleuroscopies executed in 1984–2013 in our center were considered in this study. METHODS: A retrospective observational study was performed. Observational time was divided into six series of 5 years. We calculated MT diagnostic yield and analyzed trends of main diseases diagnosed along the time. RESULTS: Along the 30 years population became progressively older. Number of pleuroscopies firstly increased, then stabilized and decreased in the last 5 years. The overall diagnostic yield of MT was 71%, increasing from 57% to 79%. The diagnostic yield was significantly higher in the presence of monolateral pleural effusion. Cancer represented more than half of diagnosis; tuberculosis was the most common nonneoplastic disease. The frequency of all cancers, mesothelioma, and lung cancer increased through the time; tuberculosis first decreased and then increased. All specimens resulted appropriate during the last 25 years. CONCLUSION: MT has a great diagnostic yield that can be improved by practice, permitting to achieve a specific histological diagnosis in about 80% of patients. Our experience demonstrates that the accurate selection of the patients undergoing to MT is very important to reach these results. PMID:27512506

  18. Selection of diagnostic tests for clinical decision making and translation to a problem oriented medical record.

    PubMed

    Realdi, Giuseppe; Previato, Lorenzo; Vitturi, Nicola

    2008-07-01

    The leading function of the physician is the clinical reasoning, which involves appropriate investigation of the problems of the patient, formulation of a diagnostic suspect based on the patient's symptoms and signs, gathering of additional relevant information, to select necessary tests and administration of the most suitable therapy. The problems of the patient are expressed by symptoms or signs or abnormal test results, requested for a variety of reasons. The entire scientific, as well as diagnostic approach, is based on three steps: to stumble in a problem; to try a solution through a hypothesis; to disprove or to prove the hypothesis by a process of criticism. Clinicians use the information obtained from the history and physical examination to estimate initial (or pre-test) probability and then use the results from tests and other diagnostic procedures to modify this probability until the post-test probability is such that the suspected diagnosis is either confirmed or ruled out. When the pre-test probability of disease is high, tests characterized by high specificity will be preferred, in order to confirm the diagnostic suspect. When the pre-test probability of disease is low, a test with high sensitivity is advisable to exclude the hypothetical disease. The above mentioned process of decision making has been transferred to a problem oriented medical record that is currently employed in our Clinic. PMID:18420030

  19. The Changing Landscape of Molecular Diagnostic Testing: Implications for Academic Medical Centers

    PubMed Central

    Rehm, Heidi L.; Hynes, Elizabeth; Funke, Birgit H.

    2016-01-01

    Over the last decade, the field of molecular diagnostics has undergone tremendous transformation, catalyzed by the clinical implementation of next generation sequencing (NGS). As technical capabilities are enhanced and current limitations are addressed, NGS is increasingly capable of detecting most variant types and will therefore continue to consolidate and simplify diagnostic testing. It is likely that genome sequencing will eventually serve as a universal first line test for disorders with a suspected genetic origin. Academic Medical Centers (AMCs), which have been at the forefront of this paradigm shift are now presented with challenges to keep up with increasing technical, bioinformatic and interpretive complexity of NGS-based tests in a highly competitive market. Additional complexity may arise from altered regulatory oversight, also triggered by the unprecedented scope of NGS-based testing, which requires new approaches. However, these challenges are balanced by unique opportunities, particularly at the interface between clinical and research operations, where AMCs can capitalize on access to cutting edge research environments and establish collaborations to facilitate rapid diagnostic innovation. This article reviews present and future challenges and opportunities for AMC associated molecular diagnostic laboratories from the perspective of the Partners HealthCare Laboratory for Molecular Medicine (LMM). PMID:26828522

  20. [The provision of quality and security of medical care on the basis of standardization of medical nurse activities in counseling diagnostic center].

    PubMed

    Chikineva, A V

    2010-01-01

    The enhancement of curative diagnostic process and the increase of its quality depend not only on the management, but on the reasonable implementation of high-tech new technologies. Nowadays, the evidence-based medical nursing practice represents an actively developing direction of medical nurse business. The State Novosibirsk oblast diagnostic center has developed the standards of nurse activities targeted to decrease the duplication in work, the provision of personnel and patient security. The audit of implementation of standards and the monitoring of nursing process permit to timely input the adjustments to the provision of quality of medical nurse care. PMID:20967968

  1. Non-invasive medical diagnostics by nanoparticle-based solid-state gas sensors

    NASA Astrophysics Data System (ADS)

    Tricoli, Antonio

    2013-08-01

    Chemical sensors made of tailored nanoparticles offer excellent miniaturization capability and are able to rapidly and continuously detect trace amounts of important analytes down to trace concentrations. Application of these sensing materials to non-invasive medical diagnostics by breath analysis has the potential to drastically reduce diagnostics costs while offering better service quality to the patients and enabling very early-stage detection of severe illnesses such as lung cancer. Here, we present a flexible approach to synthesize advanced solid-state gas sensor materials that have demonstrated reliable detection of important breath markers. In particular, the feasibility of capturing highly performing, meta-stable sensing nanoparticles by flame-synthesis of multi component metal-oxides is critically discussed.

  2. Expert Facilitated Development of an Objective Assessment Tool for Point-of-Care Ultrasound Performance in Undergraduate Medical Education

    PubMed Central

    Black, Holly; Sheppard, Gillian; Metcalfe, Brian; Stone-McLean, Jordan; McCarthy, Heather

    2016-01-01

    Background: With the various applications of point-of-care ultrasound (PoCUS) steadily increasing, many medical schools across North America are incorporating PoCUS training into their undergraduate curricula. The Faculty of Medicine at Memorial University also intends to introduce PoCUS training into its own undergraduate medical program. The proposed approach is to introduce a PoCUS curriculum focusing on anatomy and physiology while developing cognitive and psychomotor skills that are later transferred into clinical applications. This has been the common approach taken by most undergraduate ultrasound programs in the United States. This project highlights the development and the challenges involved in creating an objective assessment tool that meets the unique needs of this proposed undergraduate ultrasound curriculum. Methods: After a thorough review of existing literature and input from experts in PoCUS, a prototype global rating scale (GRS) and three exam-specific checklists were created by researchers. The exam-specific checklists include aorta exam, subxiphoid cardiac exam, and focused abdominal exam. A panel of 18 emergency room physicians certified in PoCUS were recruited to evaluate the GRS and three checklists. This was accomplished using a modified Delphi technique. The items were rated on a 5-point Likert scale. If an item received a mean score of less than 4, it was deemed unimportant for the assessment of PoCUS performance in undergraduate medical learners and was excluded. Experts were also encouraged to provide comments and suggest further items to be added to the GRS or checklists. Items were modified according to these comments. All of the edits were then sent back to the experts for revisions. Results: A consensus was achieved after three rounds of surveys, with the final GRS containing nine items. The final aorta checklist contained nine items, and the subxiphoid cardiac and focused abdominal checklists each contained 11 items. Conclusion: By

  3. Ultrasound Imaging System Video

    NASA Technical Reports Server (NTRS)

    2002-01-01

    In this video, astronaut Peggy Whitson uses the Human Research Facility (HRF) Ultrasound Imaging System in the Destiny Laboratory of the International Space Station (ISS) to image her own heart. The Ultrasound Imaging System provides three-dimension image enlargement of the heart and other organs, muscles, and blood vessels. It is capable of high resolution imaging in a wide range of applications, both research and diagnostic, such as Echocardiography (ultrasound of the heart), abdominal, vascular, gynecological, muscle, tendon, and transcranial ultrasound.

  4. [Forensic medical diagnostics of intra-vitality of the strangulation mark by morphological methods].

    PubMed

    Bogomolov, D V; Zbrueva, Yu V; Putintsev, V A; Denisova, O P

    2016-01-01

    The objective of the present study WaS to overview the current domestic and foreign literature concerning the up-to-date methods employed for the expert evaluation of intra-vitality of the strangulation mark. The secondary objective was to propose the new approaches for addressing this problem. The methods of expert diagnostics with a view to determining the time of infliction of injuries as exemplified by mechanical asphyxia are discussed. It is concluded that immunohistochemical and morphometric studies provide the most promising tools for the evaluation of intra-vitality of the strangulation mark for the purpose of forensic medical expertise. PMID:27358932

  5. Calibration of an Ultrasound Tomography System for Medical Imaging with 2D Contrast-Source Inversion

    NASA Astrophysics Data System (ADS)

    Faucher, Gabriel Paul

    This dissertation describes two possible methods for the calibration of an ultrasound tomography system developed at University of Manitoba's Electromagnetic Imaging Laboratory for imaging with the contrast-source inversion algorithm. The calibration techniques are adapted from existing procedures employed for microwave tomography. A theoretical model of these calibration principles is developed in order to provide a rationale for the effectiveness of the proposed procedures. The applicability of such an imaging algorithm and calibration methods in the context of ultrasound are discussed. Also presented are 2D and 3D finite-difference time-domain update equations for the simulation of acoustic wave propagation in inhomogeneous media. Details regarding the application of an absorbing boundary-condition, point-source modelling and the treatment of penetrable objects are included in this document.

  6. [The metrology of medical devices for the diagnostic in vitro: the European approach].

    PubMed

    Antonov, V S

    2011-12-01

    In the European Union, the measurement devices are regulated by the Directive 2004/22/EU establishing the mandatory requirements, rules of admittance and control/surveillance on the market. The medical laboratory analyzers don't come under the force of this Directive and are regulated by the Directive 98/72/EU in the same way as all medical devices for diagnostics in vitro. The new Russian Federal Law No102 "On the provision of the unification of measurements" came into force in 2009 is significantly harmonized with the similar international legislation and enable to eliminate the contradictions which for many years impeded the development of metrological support of clinical laboratory examinations. PMID:22416434

  7. Investigation of radiation protection of medical staff performing medical diagnostic examinations by using PET/CT technique.

    PubMed

    Wrzesień, Małgorzata; Napolska, Katarzyna

    2015-03-01

    Positron emission tomography (PET) is now one of the most important methods in the diagnosis of cancer diseases. Due to the rapid growth of PET/CT centres in Poland in less than a decade, radiation protection and, consequently, the assessment of worker exposure to ionising radiation, emitted mainly by the isotope (18)F, have become essential issues. The main aim of the study was to analyse the doses received by workers employed in the Medical Diagnostic Centre. The analysis comprises a physicist, three nurses, three physicians, three technicians, as well as two administrative staff employees. High-sensitivity thermoluminescent detectors (TLDs) were used to measure the doses for medical staff. The personnel was classified into categories, among them employees having direct contact with the 'source of radiation'-(18)FDG. The TLDs were placed on the fingertips of both hands and they were also attached at the level of eye lenses, thyroid and gonads depending on the assigned category. The highest dose of radiation was observed during the administration of the (18)FDG to the patients. In the case of the physicist, the highest dose was recorded during preparation of the radiopharmaceutical-(18)FDG. The body parts most exposed to ionizing radiation are the fingertips of the thumb, index and middle finger. PMID:25647828

  8. Parallel Digital Watermarking Process on Ultrasound Medical Images in Multicores Environment

    PubMed Central

    Khor, Hui Liang; Liew, Siau-Chuin; Zain, Jasni Mohd.

    2016-01-01

    With the advancement of technology in communication network, it facilitated digital medical images transmitted to healthcare professionals via internal network or public network (e.g., Internet), but it also exposes the transmitted digital medical images to the security threats, such as images tampering or inserting false data in the images, which may cause an inaccurate diagnosis and treatment. Medical image distortion is not to be tolerated for diagnosis purposes; thus a digital watermarking on medical image is introduced. So far most of the watermarking research has been done on single frame medical image which is impractical in the real environment. In this paper, a digital watermarking on multiframes medical images is proposed. In order to speed up multiframes watermarking processing time, a parallel watermarking processing on medical images processing by utilizing multicores technology is introduced. An experiment result has shown that elapsed time on parallel watermarking processing is much shorter than sequential watermarking processing. PMID:26981111

  9. Parallel Digital Watermarking Process on Ultrasound Medical Images in Multicores Environment.

    PubMed

    Khor, Hui Liang; Liew, Siau-Chuin; Zain, Jasni Mohd

    2016-01-01

    With the advancement of technology in communication network, it facilitated digital medical images transmitted to healthcare professionals via internal network or public network (e.g., Internet), but it also exposes the transmitted digital medical images to the security threats, such as images tampering or inserting false data in the images, which may cause an inaccurate diagnosis and treatment. Medical image distortion is not to be tolerated for diagnosis purposes; thus a digital watermarking on medical image is introduced. So far most of the watermarking research has been done on single frame medical image which is impractical in the real environment. In this paper, a digital watermarking on multiframes medical images is proposed. In order to speed up multiframes watermarking processing time, a parallel watermarking processing on medical images processing by utilizing multicores technology is introduced. An experiment result has shown that elapsed time on parallel watermarking processing is much shorter than sequential watermarking processing. PMID:26981111

  10. Update of diagnostic medical and dental x-ray exposures in Romania.

    PubMed

    Sorop, Ioana; Mossang, Daniela; Iacob, Mihai Radu; Dadulescu, Elena; Iacob, Olga

    2008-12-01

    This national study, the third in the last 15 years, updates the magnitude of medical radiation exposure from conventional x-ray examinations, in order to optimise the radiological protection to the population in a cost-effective manner. Effective doses from diagnostic radiology were estimated for adult and paediatric patients undergoing the 20 most important types of x-ray examination. Data were collected from 179 x-ray departments, selected by their annual workload, throughout the country. Estimates were made using two dosimetric quantities: entrance surface dose, derived from the absorbed dose in air measured by simulation of radiographic examinations, and dose-area product, measured during fluoroscopic examinations performed on adult and paediatric patients. Conversion coefficients to effective dose of the UK National Radiological Protection Board (NRPB) have been used in all calculations. The effective dose per patient from all medical x-ray examinations was 0.74 mSv and the resulting annual collective effective dose was 6930 man Sv, with annual effective dose per caput of 0.33 mSv. The current size of population exposure from diagnostic radiology is lower than the previous one by 40%, but could be about 30% higher by taking into account the estimated contribution from computed tomography (CT) procedures. PMID:19029586

  11. A prospective study of medical diagnostic radiography and risk of thyroid cancer.

    PubMed

    Neta, Gila; Rajaraman, Preetha; Berrington de Gonzalez, Amy; Doody, Michele M; Alexander, Bruce H; Preston, Dale; Simon, Steven L; Melo, Dunstana; Miller, Jeremy; Freedman, D Michal; Linet, Martha S; Sigurdson, Alice J

    2013-04-15

    Although diagnostic x-ray procedures provide important medical benefits, cancer risks associated with their exposure are also possible, but not well characterized. The US Radiologic Technologists Study (1983-2006) is a nationwide, prospective cohort study with extensive questionnaire data on history of personal diagnostic imaging procedures collected prior to cancer diagnosis. We used Cox proportional hazard regressions to estimate thyroid cancer risks related to the number and type of selected procedures. We assessed potential modifying effects of age and calendar year of the first x-ray procedure in each category of procedures. Incident thyroid cancers (n = 251) were diagnosed among 75,494 technologists (1.3 million person-years; mean follow-up = 17 years). Overall, there was no clear evidence of thyroid cancer risk associated with diagnostic x-rays except for dental x-rays. We observed a 13% increase in thyroid cancer risk for every 10 reported dental radiographs (hazard ratio = 1.13, 95% confidence interval: 1.01, 1.26), which was driven by dental x-rays first received before 1970, but we found no evidence that the relationship between dental x-rays and thyroid cancer was associated with childhood or adolescent exposures as would have been anticipated. The lack of association of thyroid cancer with x-ray procedures that expose the thyroid to higher radiation doses than do dental x-rays underscores the need to conduct a detailed radiation exposure assessment to enable quantitative evaluation of risk. PMID:23529772

  12. Model selection for a medical diagnostic decision support system: a breast cancer detection case.

    PubMed

    West, D; West, V

    2000-11-01

    There are a number of different quantitative models that can be used in a medical diagnostic decision support system (MDSS) including parametric methods (linear discriminant analysis or logistic regression), non-parametric models (K nearest neighbor, or kernel density) and several neural network models. The complexity of the diagnostic task is thought to be one of the prime determinants of model selection. Unfortunately, there is no theory available to guide model selection. Practitioners are left to either choose a favorite model or to test a small subset using cross validation methods. This paper illustrates the use of a self-organizing map (SOM) to guide model selection for a breast cancer MDSS. The topological ordering properties of the SOM are used to define targets for an ideal accuracy level similar to a Bayes optimal level. These targets can then be used in model selection, variable reduction, parameter determination, and to assess the adequacy of the clinical measurement system. These ideas are applied to a successful model selection for a real-world breast cancer database. Diagnostic accuracy results are reported for individual models, for ensembles of neural networks, and for stacked predictors. PMID:10998586

  13. Radiological safety status and quality assurance audit of medical X-ray diagnostic installations in India.

    PubMed

    Sonawane, A U; Singh, Meghraj; Sunil Kumar, J V K; Kulkarni, Arti; Shirva, V K; Pradhan, A S

    2010-10-01

    We conducted a radiological safety and quality assurance (QA) audit of 118 medical X-ray diagnostic machines installed in 45 major hospitals in India. The main objective of the audit was to verify compliance with the regulatory requirements stipulated by the national regulatory body. The audit mainly covered accuracy check of accelerating potential (kVp), linearity of tube current (mA station) and timer, congruence of radiation and optical field, and total filtration; in addition, we also reviewed medical X-ray diagnostic installations with reference to room layout of X-ray machines and conduct of radiological protection survey. A QA kit consisting of a kVp Test-O-Meter (ToM) (Model RAD/FLU-9001), dose Test-O-Meter (ToM) (Model 6001), ionization chamber-based radiation survey meter model Gun Monitor and other standard accessories were used for the required measurements. The important areas where there was noncompliance with the national safety code were: inaccuracy of kVp calibration (23%), lack of congruence of radiation and optical field (23%), nonlinearity of mA station (16%) and timer (9%), improper collimator/diaphragm (19.6%), faulty adjustor knob for alignment of field size (4%), nonavailability of warning light (red light) at the entrance of the X-ray room (29%), and use of mobile protective barriers without lead glass viewing window (14%). The present study on the radiological safety status of diagnostic X-ray installations may be a reasonably good representation of the situation in the country as a whole. The study contributes significantly to the improvement of radiological safety by the way of the steps already taken and by providing a vital feed back to the national regulatory body. PMID:21170188

  14. Case report of medical thoracoscopy and endobronchial ultrasound bronchoscopy in the workup of giant solitary fibrous tumor of the pleura.

    PubMed

    Dammad, Tarek; Duchesne, Joshua; Pasnick, Susan

    2016-07-01

    Solitary fibrous tumor of the pleura (SFTP) is a rare tumor of fibroblastic origin. It can be quite vascular, and its surgical management carries the risk of a major intra-operative bleed. The pre-operative use of endobronchial ultrasound (EBUS) to visualize the vascular supply of the tumor has not been reported.We report a case of a patient presenting with progressive shortness of breath and cough who was found to have a very large pleural-based tumor. We describe the use of medical thoracoscopy and EBUS to establish the diagnosis of SFTP and to characterize the blood supply of the tumor.In the future, EBUS may provide an alternative to conventional angiography for both mapping and embolizing tumor blood supply. PMID:27399107

  15. Dual Processing Model for Medical Decision-Making: An Extension to Diagnostic Testing.

    PubMed

    Tsalatsanis, Athanasios; Hozo, Iztok; Kumar, Ambuj; Djulbegovic, Benjamin

    2015-01-01

    Dual Processing Theories (DPT) assume that human cognition is governed by two distinct types of processes typically referred to as type 1 (intuitive) and type 2 (deliberative). Based on DPT we have derived a Dual Processing Model (DPM) to describe and explain therapeutic medical decision-making. The DPM model indicates that doctors decide to treat when treatment benefits outweigh its harms, which occurs when the probability of the disease is greater than the so called "threshold probability" at which treatment benefits are equal to treatment harms. Here we extend our work to include a wider class of decision problems that involve diagnostic testing. We illustrate applicability of the proposed model in a typical clinical scenario considering the management of a patient with prostate cancer. To that end, we calculate and compare two types of decision-thresholds: one that adheres to expected utility theory (EUT) and the second according to DPM. Our results showed that the decisions to administer a diagnostic test could be better explained using the DPM threshold. This is because such decisions depend on objective evidence of test/treatment benefits and harms as well as type 1 cognition of benefits and harms, which are not considered under EUT. Given that type 1 processes are unique to each decision-maker, this means that the DPM threshold will vary among different individuals. We also showed that when type 1 processes exclusively dominate decisions, ordering a diagnostic test does not affect a decision; the decision is based on the assessment of benefits and harms of treatment. These findings could explain variations in the treatment and diagnostic patterns documented in today's clinical practice. PMID:26244571

  16. Dual Processing Model for Medical Decision-Making: An Extension to Diagnostic Testing

    PubMed Central

    Tsalatsanis, Athanasios; Hozo, Iztok; Kumar, Ambuj; Djulbegovic, Benjamin

    2015-01-01

    Dual Processing Theories (DPT) assume that human cognition is governed by two distinct types of processes typically referred to as type 1 (intuitive) and type 2 (deliberative). Based on DPT we have derived a Dual Processing Model (DPM) to describe and explain therapeutic medical decision-making. The DPM model indicates that doctors decide to treat when treatment benefits outweigh its harms, which occurs when the probability of the disease is greater than the so called “threshold probability” at which treatment benefits are equal to treatment harms. Here we extend our work to include a wider class of decision problems that involve diagnostic testing. We illustrate applicability of the proposed model in a typical clinical scenario considering the management of a patient with prostate cancer. To that end, we calculate and compare two types of decision-thresholds: one that adheres to expected utility theory (EUT) and the second according to DPM. Our results showed that the decisions to administer a diagnostic test could be better explained using the DPM threshold. This is because such decisions depend on objective evidence of test/treatment benefits and harms as well as type 1 cognition of benefits and harms, which are not considered under EUT. Given that type 1 processes are unique to each decision-maker, this means that the DPM threshold will vary among different individuals. We also showed that when type 1 processes exclusively dominate decisions, ordering a diagnostic test does not affect a decision; the decision is based on the assessment of benefits and harms of treatment. These findings could explain variations in the treatment and diagnostic patterns documented in today’s clinical practice. PMID:26244571

  17. Infrared mapping of ultrasound fields generated by medical transducers: Feasibility of determining absolute intensity levels

    PubMed Central

    Khokhlova, Vera A.; Shmeleva, Svetlana M.; Gavrilov, Leonid R.; Martin, Eleanor; Sadhoo, Neelaksh; Shaw, Adam

    2013-01-01

    Considerable progress has been achieved in the use of infrared (IR) techniques for qualitative mapping of acoustic fields of high intensity focused ultrasound (HIFU) transducers. The authors have previously developed and demonstrated a method based on IR camera measurement of the temperature rise induced in an absorber less than 2 mm thick by ultrasonic bursts of less than 1 s duration. The goal of this paper was to make the method more quantitative and estimate the absolute intensity distributions by determining an overall calibration factor for the absorber and camera system. The implemented approach involved correlating the temperature rise measured in an absorber using an IR camera with the pressure distribution measured in water using a hydrophone. The measurements were conducted for two HIFU transducers and a flat physiotherapy transducer of 1 MHz frequency. Corresponding correction factors between the free field intensity and temperature were obtained and allowed the conversion of temperature images to intensity distributions. The system described here was able to map in good detail focused and unfocused ultrasound fields with sub-millimeter structure and with local time average intensity from below 0.1 W/cm2 to at least 50 W/cm2. Significantly higher intensities could be measured simply by reducing the duty cycle. PMID:23927199

  18. Infrared mapping of ultrasound fields generated by medical transducers: feasibility of determining absolute intensity levels.

    PubMed

    Khokhlova, Vera A; Shmeleva, Svetlana M; Gavrilov, Leonid R; Martin, Eleanor; Sadhoo, Neelaksh; Shaw, Adam

    2013-08-01

    Considerable progress has been achieved in the use of infrared (IR) techniques for qualitative mapping of acoustic fields of high intensity focused ultrasound (HIFU) transducers. The authors have previously developed and demonstrated a method based on IR camera measurement of the temperature rise induced in an absorber less than 2 mm thick by ultrasonic bursts of less than 1 s duration. The goal of this paper was to make the method more quantitative and estimate the absolute intensity distributions by determining an overall calibration factor for the absorber and camera system. The implemented approach involved correlating the temperature rise measured in an absorber using an IR camera with the pressure distribution measured in water using a hydrophone. The measurements were conducted for two HIFU transducers and a flat physiotherapy transducer of 1 MHz frequency. Corresponding correction factors between the free field intensity and temperature were obtained and allowed the conversion of temperature images to intensity distributions. The system described here was able to map in good detail focused and unfocused ultrasound fields with sub-millimeter structure and with local time average intensity from below 0.1 W/cm(2) to at least 50 W/cm(2). Significantly higher intensities could be measured simply by reducing the duty cycle. PMID:23927199

  19. [Ultrasound and color Doppler in nephrology. Physical and technical principles].

    PubMed

    Meola, Mario; Petrucci, Ilaria

    2012-01-01

    Sonography is an imaging technique that generates tomographic images using ultrasound. The sound constitutes mechanical energy transmitted in a medium by pressure waves. Sound waves with frequencies greater than 20 kHz are called ultrasounds. Diagnostic ultrasounds use frequencies from 1 to 20 MHz. Ultrasound equipment is composed of a scanner, an image monitor, and different transducers that transform acoustic energy into electrical signals and electrical energy into acoustic energy (piezoelectric effect). The spatial resolution defines the minimum distance between two reflectors or echogenic regions that can be imaged as separate reflectors. The spatial resolution is mainly determined by the array design (linear, curved and sectorial) and by the operative system of the transducer. Modern ultrasound machines are very sophisticated medical devices that often support many transducers, imaging modes and display devices. The scan converter memory is the device in which images are formed and then presented to the monitor and to the hard copy devices. PMID:22388909

  20. Diagnostic Value of Convex Probe Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration in Mediastinal Tuberculous Lymphadenitis: A Systematic Review and Meta-Analysis

    PubMed Central

    Li, Wei; Zhang, Ting; Chen, Yuqing; Liu, Chao; Peng, Wenjia

    2015-01-01

    Background Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) has been widely used in the diagnosis of mediastinal lymphadenopathies. Here, we performed a systematic review and meta-analysis to explore the diagnostic value of EBUS-TBNA in mediastinal tuberculous lymphadenopathy (TBLA). Material/Methods PubMed, EMBASE, and Sinoced were systematically searched for articles published in English or Chinese that reported the diagnostic yield of EBUS-TBNA in mediastinal TBLA. The quality of studies was assessed using the QualSyst tool. Using 95% confidence intervals (CI), the diagnostic yields of EBUS-TBNA were calculated for the individual studies, and the results were then pooled using a random-effects model. Heterogeneity and publication bias were also assessed. Results A total of 14 studies, consisting of 684 patients with mediastinal TBLA, were finally included. The pooled diagnostic yield of EBUS-TBNA for mediastinal TBLA was 80% (95% CI: 74–86%). Significant heterogeneity (I2=77.9%) and significant publication bias were detected (Begg’s test p=0.05 and Egger’s test p=0.02). From subgroup analyses, significant differences in the diagnostic yield of EBUS-TBNA were associated with Asian vs. European (UK) studies, retrospective vs. prospective studies, those employing rapid on-site cytological evaluation vs. not, those employing different anesthetic types, and those employing smear vs. culture. However, microbiological examination and the number of lymph node passes did not have a significant effect on the diagnostic yield of EBUS-TBNA. Fifteen minor complications for EBUS-TBNA were reported. Conclusions EBUS-TBNA appears to be an efficacious and safe procedure and should be used as an initial diagnostic tool for mediastinal TBLA. PMID:26177653

  1. High-Frequency (>50 MHz) Medical Ultrasound Linear Arrays Fabricated From Micromachined Bulk PZT Materials

    PubMed Central

    Liu, Changgeng; Zhou, Qifa; Djuth, Frank T.; Shung, K. Kirk

    2012-01-01

    This paper describes the development and characterization of a high-frequency (65-MHz) ultrasound transducer linear array. The array was built from bulk PZT which was etched using an optimized chlorine-based plasma dry-etching process. The median etch rate of 8 μm/h yielded a good profile (wall) angle (>83°) and a reasonable processing time for etch depths up to 40 μm (which corresponds to a 50-MHz transducer). A backing layer with an acoustic impedance of 6 MRayl and a front-end polymer matching layer yielded a transducer bandwidth of 40%. The major parameters of the transducer have been characterized. The two-way insertion loss and crosstalk between adjacent channels at the center frequency are 26.5 and −25 dB, respectively. PMID:24626041

  2. Note: Comparative experimental studies on the performance of 2-2 piezocomposite for medical ultrasound transducers.

    PubMed

    Marinozzi, F; Bini, F; Biagioni, A; Grandoni, A; Spicci, L

    2013-09-01

    The paper reports the experimental investigation of the behavior of 2-2 Lead Zirconate Titanate (PZT)-polymer composite transducers array for clinical ultrasound equipments. Several 2-2 plate composites having the same dicing pitch of 0.11 mm and different volume fractions were manufactured and investigated. Measurements were performed through different techniques such as electrical impedance, pulse-echo, and Laser Doppler Vibrometer. With the last one, maps of the surface displacement were presented relative to thickness mode and first lateral mode resonance frequencies. The transducers with volume fractions of the 40% resulted markedly inefficient, whereas the largest bandwidth and best band shape were achieved by the 50%. PMID:24089885

  3. ASIC design of a digital fuzzy system on chip for medical diagnostic applications.

    PubMed

    Roy Chowdhury, Shubhajit; Roy, Aniruddha; Saha, Hiranmay

    2011-04-01

    The paper presents the ASIC design of a digital fuzzy logic circuit for medical diagnostic applications. The system on chip under consideration uses fuzzifier, memory and defuzzifier for fuzzifying the patient data, storing the membership function values and defuzzifying the membership function values to get the output decision. The proposed circuit uses triangular trapezoidal membership functions for fuzzification patients' data. For minimizing the transistor count, the proposed circuit uses 3T XOR gates and 8T adders for its design. The entire work has been carried out using TSMC 0.35 µm CMOS process. Post layout TSPICE simulation of the whole circuit indicates a delay of 31.27 ns and the average power dissipation of the system on chip is 123.49 mW which indicates a less delay and less power dissipation than the comparable embedded systems reported earlier. PMID:20703567

  4. Iliad and Medical HouseCall: evaluating the impact of common sense knowledge on the diagnostic accuracy of a medical expert system.

    PubMed Central

    Bouhaddou, O.; Lambert, J. G.; Morgan, G. E.

    1995-01-01

    Diagnostic expert systems are gaining acceptance among physicians. Recently, a comparative study of the performance of four major commercial diagnostic programs demonstrated that the information they produce contains a certain amount of irrelevancy that the trained physician ignores. Medical HouseCall is a consumer health information expert system based on a medical expert system for physicians, Iliad. To enhance the usefulness of Medical HouseCall to health care consumers, we are interested in significantly reducing the amount of irrelevancy contained in the diagnostic differential list. Testing with over 470 'textbook' cases revealed that a large part of the irrelevancy can be eliminated by adding universal and medical 'common sense' knowledge. Using four performance measures, we compared, on a subset of cases, the differential lists from two versions of the program: the refined knowledge base (1995) and an older version (1994) 'pre-common sense'. The results suggest that the performance of a diagnostic expert system can be significantly improved with the addition of common sense knowledge. PMID:8563388

  5. Tracked ultrasound elastography (TRUE)

    NASA Astrophysics Data System (ADS)

    Foroughi, Pezhman

    Medical ultrasound research has experienced a renaissance in the past decade leading to innovations in flow mapping, elasticity and thermal imaging, measurement of optical properties, beamforming, and image enhancement. In this thesis, we focus on ultrasound elastography, an emerging imaging modality with great potential to become a part of several ultrasound diagnostic applications. Elastography images the stiffness of soft tissue by applying a mechanical stimulus and estimating the disturbance created by this stimulus. In freehand elastography, soft tissue is palpated by hand using the ultrasound transducer. The elastography image is generated by comparing the pre- and post-compression images to form a displacement map which is then differentiated to produce the final strain map. To achieve the best result in freehand elastography, the sonographer must compress and decompress the tissue uniformly in a specific direction with adequate compression. This can be a difficult task even for trained users. A small rotational or out-of-plane motion in the collected ultrasound frames can render them unusable for elastography. This has made freehand elastography highly qualitative and user-dependent. We tackle this issue by incorporating the extra information from a position sensor attached to the ultrasound transducer. Our aim is to show that the localization information of ultrasound images may be utilized to improve the quality and reliability of freehand elastography. For this purpose, we have developed a frame selection scheme that finds pairs of images with optimal compression and minimal lateral and out-of-plane displacement. Relying on the localization information, our algorithm merges multiple strain images computed from the selected frame pairs. This method is applicable to both 2D and 3D elastography. Our 3D elastography does not require for the transducer to be held still during the acquisition of each volume. Instead, the sonographer freely palpates the tissue

  6. A new high definition zoom method based on compounded direct pixel beamforming for medical ultrasound imaging: preliminary results

    NASA Astrophysics Data System (ADS)

    Yoon, Sungsoo; Lee, Jongpil; Chang, Jin Ho; Song, Tai-Kyong; Yoo, Yangmo

    2013-03-01

    Conventional ultrasound imaging based on scan conversion suffers from blurring artifacts caused by interpolation[1]. Especially, when zooming an image for enlarging lesions during scan conversion (i.e., read-zoom), this blurring artifact becomes severe. To reduce blurring artifacts, a write-zoom method was previously proposed. However, it still presents blurring artifacts and lowers the frame rate due to increased line density. In this paper, a new high definition zoom method based on compounded direct pixel beamforming (CDPB) capable enhancing the detail and boundary of lesions is presented. The performance of the proposed method was evaluated with phantom and in vivo experiments by measuring the information entropy contrast (IEC). The radio-frequency channel data were acquired by using a 3.5-MHz convex array transducer with the SonixTouch research platform (Ultrasonix Medical Corp., Vancouver, BC, Canada). The enlarged images using a new high-definition zoom method based on CDPB (i.e., HDZ-CDPB) with 128 transmit scanlines were reconstructed along with read- and write zoom (RZ and WZ) images based on scan conversion by using 128 and 256 transmit scanlines, respectively. From the phantom experiments, the IEC value with the proposed HDZCDPB method was enhanced by maximally 42% and 29% compared to the RZ and WZ methods, respectively. This preliminary results indicate that the proposed HDZ-CDPB method would be useful for generating a high definition ultrasound zoom image with improved image quality compared to the conventional scan conversion based methods (i.e., RZ and WZ) while achieving the high frame rate.

  7. Impact of Endobronchial Ultrasound (EBUS) Training on the Diagnostic Yield of Conventional Transbronchial Needle Aspiration for Lymph Node Stations 4R and 7

    PubMed Central

    Sehgal, Inderpaul Singh; Dhooria, Sahajal; Gupta, Nalini; Bal, Amanjit; Ram, Babu; Aggarwal, Ashutosh Nath; Behera, Digambar; Agarwal, Ritesh

    2016-01-01

    Background There is sparse literature on whether training in endobronchial ultrasound (EBUS)-guided transbronchial needle aspiration (TBNA) improves the diagnostic yield of conventional TBNA (cTBNA). Objectives The aim of this study was to evaluate the diagnostic yield of cTBNA before and after the introduction of EBUS. Methods This was a retrospective analysis of patients who underwent cTBNA at our center. The study was divided into two periods, before and after the introduction of EBUS at our facility. The diagnostic yield of cTBNA was compared between the study periods. Rapid on-site cytological examination was not available. Results A total of 1,050 patients (61.6% men; mean age 45.6 years) underwent cTBNA during the study period (849 before EBUS; 201 after EBUS). Sarcoidosis (n = 527) followed by bronchogenic carcinoma (n = 222) formed the most common indications for performing cTBNA. There was a significant increase in both the success of obtaining a representative sample (from 71% to 85%), and the diagnostic yield (from 33% to 49.5%) of cTBNA, after the introduction of EBUS. The increase in the diagnostic yield of cTBNA after introduction of EBUS remained significant even after adjusting for years of performing cTBNA and the type of anesthesia (topical vs. sedation and topical) on a multivariate analysis. Conclusion The diagnostic yield of cTBNA at our facility increased after the introduction of EBUS-TBNA. However, given the retrospective nature of the study, prospective studies are required to confirm our findings. PMID:27083009

  8. Evaluation of Human Research Facility Ultrasound With the ISS Video System

    NASA Technical Reports Server (NTRS)

    Melton, Shannon; Sargsyan, Ashot

    2003-01-01

    Most medical equipment on the International Space Station (ISS) is manifested as part of the U.S. or the Russian medical hardware systems. However, certain medical hardware is also available as part of the Human Research Facility. The HRF and the JSC Medical Operations Branch established a Memorandum of Agreement for joint use of certain medical hardware, including the HRF ultrasound system, the only diagnostic imaging device currently manifested to fly on ISS. The outcome of a medical contingency may be changed drastically, or an unnecessary evacuation may be prevented, if clinical decisions are supported by timely and objective diagnostic information. In many higher-probability medical scenarios, diagnostic ultrasound is a first-choice modality or provides significant diagnostic information. Accordingly, the Clinical Care Capability Development Project is evaluating the HRF ultrasound system for its utility in relevant clinical situations on board ISS. For effective management of these ultrasound-supported ISS medical scenarios, the resulting data should be available for viewing and interpretation on the ground, and bidirectional voice communication should be readily available to allow ground experts (sonographers, physicians) to provide guidance to the Crew Medical Officer. It may also be vitally important to have the capability of real-time guidance via video uplink to the CMO-operator during an exam to facilitate the diagnosis in a timely fashion. In this document, we strove to verify that the HRF ultrasound video output is compatible with the ISS video system, identify ISS video system field rates and resolutions that are acceptable for varying clinical scenaiios, and evaluate the HRF ultrasound video with a commercial, off-the-shelf video converter, and compare it with the ISS video system.

  9. Surface tension in human pathophysiology and its application as a medical diagnostic tool

    PubMed Central

    Fathi-Azarbayjani, Anahita; Jouyban, Abolghasem

    2015-01-01

    Introduction: Pathological features of disease appear to be quite different. Despite this diversity, the common feature of various disorders underlies physicochemical and biochemical factors such as surface tension. Human biological fluids comprise various proteins and phospholipids which are capable of adsorption at fluid interfaces and play a vital role in the physiological function of human organs. Surface tension of body fluids correlates directly to the development of pathological states. Methods: In this review, the variety of human diseases mediated by the surface tension changes of biological phenomena and the failure of biological fluids to remain in their native state are discussed. Results: Dynamic surface tension measurements of human biological fluids depend on various parameters such as sex, age and changes during pregnancy or certain disease. It is expected that studies of surface tension behavior of human biological fluids will provide additional information and might become useful in medical practice. Theoretical background on surface tension measurement and surface tension values of reference fluids obtained from healthy and sick patients are depicted. Conclusion: It is well accepted that no single biomarker will be effective in clinical diagnosis. The surface tension measurement combined with routine lab tests may be a novel non-invasive method which can not only facilitate the discovery of diagnostic models for various diseases and its severity, but also be a useful tool for monitoring treatment efficacy. We therefore expect that studies of surface tension behavior of human biological fluids will provide additional useful information in medical practice. PMID:25901295

  10. Design of an affordable fluorescence confocal laser scanning microscope for medical diagnostics

    NASA Astrophysics Data System (ADS)

    Bechtel, Christin; Knobbe, Jens; Grüger, Heinrich; Lakner, Hubert

    2012-12-01

    Confocal fluorescence microscopes are a promising imaging tool in medical diagnostics due to their capability to selectively survey cross-sections of individual layers from `thick' samples. Non-invasive depth resolved investigation of neoplastic skin disorders is one example among other applications. However these microscopes are at present uncommon in medical practice. This is due to their main application area in research. The instruments dealt with here are generally complex, stationary units and are accordingly cost-intensive. It is for this reason, that we have designed a robust and portable MEMS based confocal fluorescence microscope with a field of view of 0.6mm x 0.6mm. This has been made possible by the integration of a 2D micro scanner mirror developed at Fraunhofer IPMS. A variable acquisition depth of cross-sectional images of the fluorescence specimen is enabled by an integrated z-shifter. With the use of commercially available optics an optical demonstrator set up has been realized. To characterize and to demonstrate the ability of this system test measurements were performed. The resolution of the microscope is better than 228 lp/mm determined by 1951 USAF resolution test target. Images of various biological samples are presented and optical sectioning capabilities are shown. A comparison of the measured with the predicted system performance will be given.

  11. Computational evidence for a discrete-scatterer aberration model in medical ultrasound

    NASA Astrophysics Data System (ADS)

    Lacefield, James C.

    2001-05-01

    Many techniques for correcting ultrasound focus distortion model the aberrating properties of tissue with a single time-shift screen, but simulations and phantom studies suggest single-screen models are ineffective for transmit focus compensation. Extension of the models to include multiple parallel screens is a logical increment in complexity, but the number of screens must be manageable and readily determined to yield practical aberration correction methods. To assess the feasibility of multi-screen strategies, simulations were performed to search for a general form for the aberration profile of breast tissue. Two-dimensional propagation of 3-MHz planar wavefronts through digitized breast specimens was computed using a k-space method [Tabei et al., J. Acoust. Soc. Am. 111, 53-63 (2002)] and waveforms were sampled at 1-mm intervals along the propagation direction. Arrival time, amplitude, and coherence fluctuations were correlated with scattering from distinct structures. This observation was most apparent when the first derivatives of those parameters with respect to the propagation direction were compared with the connective tissue architecture in the specimens. The assumption underlying time-shift screen models that aberration arises from smooth fluctuations in the acoustic properties of tissue merits reexamination. [Research supported by an NSERC Discovery Grant.

  12. The modified ultrasound pattern sum score mUPSS as additional diagnostic tool for genetically distinct hereditary neuropathies.

    PubMed

    Grimm, Alexander; Rasenack, Maria; Athanasopoulou, Ioanna M; Dammeier, Nele Maria; Lipski, Christina; Wolking, Stefan; Vittore, Debora; Décard, Bernhard F; Axer, Hubertus

    2016-02-01

    The objective of this study is to evaluate the nerve ultrasound characteristics in genetically distinct inherited neuropathies, the value of the modified ultrasound pattern sum score (mUPSS) to differentiate between the subtypes and the correlation of ultrasound with nerve conduction studies (NCS), disease duration and severity. All patients underwent a standardized neurological examination, ultrasound, and NCS. In addition, genetic testing was performed. Consequently, mUPSS was applied, which is a sum-score of cross-sectional areas (CSA) at predefined anatomical points in different nerves. 31 patients were included (10xCharcot-Marie-Tooth (CMT)1a, 3xCMT1b, 3xCMTX, 9xCMT2, 6xHNPP [Hereditary neuropathy with liability to pressure palsies]). Generalized, homogeneous nerve enlargement and significantly increased UPS scores emphasized the diagnosis of demyelinating neuropathy, particularly CMT1a and CMT1b. The amount of enlargement did not depend on disease duration, symptom severity, height and weight. In CMTX the nerves were enlarged, as well, however, only in the roots and lower limbs, most prominent in men. In CMT2 no significant enlargement was detectable. In HNPP the CSA values were increased at entrapped sites, and not elsewhere. However, a distinction from CMT1, which also showed enlarged CSA values at entrapment sites, was only possible by calculating the entrapment ratios and entrapment score. The mUPSS allowed distinction between CMT1a (increased UPS scores, entrapment ratios <1.0) and HNPP (low UPS scores, entrapment ratios >1.4), while CMT1b and CMTX showed intermediate UPS types and entrapment ratios <1.0. Although based on few cases, ultrasound revealed consistent and homogeneous nerve alteration in certain inherited neuropathies. The modified UPSS is a quantitative tool, which may provide useful information for diagnosis, differentiation and follow-up evaluation in addition to NCS and molecular testing. PMID:26559821

  13. SU-E-P-01: An Informative Review On the Role of Diagnostic Medical Physicist in the Academic and Private Medical Centers

    SciTech Connect

    Weir, V; Zhang, J

    2014-06-01

    Purpose: The role of physicist in the academic and private hospital environment continues to evolve and expand. This becomes more obvious with the newly revised requirements of the Joint Commission (JC) on imaging modalities and the continued updated requirements of ACR accreditation for medical physics (i.e., starting in June 2014, a physicists test will be needed before US accreditation). We provide an informative review on the role of diagnostic medical physicist and hope that our experience will expedite junior physicists in understanding their role in medical centers, and be ready to more opportunities. Methods: Based on our experience, diagnostic medical physicists in both academic and private medical centers perform several clinical functions. These include providing clinical service and physics support, ensuring that all ionizing radiation devices are tested and operated in compliance with the State and Federal laws, regulations and guidelines. We also discuss the training and education required to ensure that the radiation exposure to patients and staff is as low as reasonably achievable. We review the overlapping roles of medical and health physicist in some institutions. Results: A detailed scheme on the new requirements (effective 7/1/2014) of the JC is provided. In 2015, new standards for fluoroscopy, cone beam CT and the qualifications of staff will be phased in. A summary of new ACR requirements for different modalities is presented. Medical physicist have other duties such as sitting on CT and fluoroscopy committees for protocols design, training of non-radiologists to meet the new fluoroscopy rules, as well as helping with special therapies such as Yittrium 90 cases. Conclusion: Medical physicists in both academic and private hospitals are positioned to be more involved and prominent. Diagnostic physicists need to be more proactive to involve themselves in the day to day activities of the radiology department.

  14. Protection of patients in diagnostic and interventional medical imaging: collaboration is the key.

    PubMed

    Applegate, Kimberly E

    2015-02-01

    The radiology community (medical physicists, radiologic technologists, radiologists, and interventional proceduralists) has led the educational and awareness efforts in the medical arena to reduce radiation dose to patients through effective collaborations that bridge traditional medical specialty silos to reach health worker stakeholders. These successful collaborations have also included both vendors and regulators, with the overarching goal of radiation protection of patients (justification, optimization, and use of dose reference levels). This focus on patients often raises overall safety awareness and lowers occupational radiation doses as well. It is critical that the entire radiology community continue to act as leaders in these radiation safety efforts for both employees and patients. In order to be successful, it is important to understand safety culture and the growing, worldwide, multimedia resources that are available. There is little time or budget to recreate or duplicate training materials or risk communication information that may already exist. Together with the increasingly fast-paced and demanding healthcare environment and sharp focus on quality, it has never been more important to understand how to achieve better quality care for radiology departments. It is also important to measure and report quality for many customers, including patients, referring providers, and many other stakeholders. This short report will briefly define safety culture and describe methods for using collective learning tools that document radiation protection of patients in diagnostic and interventional imaging. These tools include the use of imaging modality registries, such as the Computed Tomography Does Index Registry, peer review of imaging reports, the use of clinical decision support, and guidelines. Finally, the Image Gently and Image Wisely campaigns provide examples of cross-disciplinary collaboration to improve radiation protection of patients. PMID:25551505

  15. CT and Ultrasound Guided Stereotactic High Intensity Focused Ultrasound (HIFU)

    SciTech Connect

    Wood, Bradford J.; Frenkel, V.; Viswanathan, A.; Dromi, S.; Oh, K.; Kam, A.; Li, K. C. P.; Yanof, J.; Bauer, C.; Kruecker, J.; Seip, R.

    2006-05-08

    To demonstrate the feasibility of CT and B-mode Ultrasound (US) targeted HIFU, a prototype coaxial focused ultrasound transducer was registered and integrated to a CT scanner. CT and diagnostic ultrasound were used for HIFU targeting and monitoring, with the goals of both thermal ablation and non-thermal enhanced drug delivery. A 1 megahertz coaxial ultrasound transducer was custom fabricated and attached to a passive position-sensing arm and an active six degree-of-freedom robotic arm via a CT stereotactic frame. The outer therapeutic transducer with a 10 cm fixed focal zone was coaxially mounted to an inner diagnostic US transducer (2-4 megahertz, Philips Medical Systems). This coaxial US transducer was connected to a modified commercial focused ultrasound generator (Focus Surgery, Indianapolis, IN) with a maximum total acoustic power of 100 watts. This pre-clinical paradigm was tested for ability to heat tissue in phantoms with monitoring and navigation from CT and live US. The feasibility of navigation via image fusion of CT with other modalities such as PET and MRI was demonstrated. Heated water phantoms were tested for correlation between CT numbers and temperature (for ablation monitoring). The prototype transducer and integrated CT/US imaging system enabled simultaneous multimodality imaging and therapy. Pre-clinical phantom models validated the treatment paradigm and demonstrated integrated multimodality guidance and treatment monitoring. Temperature changes during phantom cooling corresponded to CT number changes. Contrast enhanced or non-enhanced CT numbers may potentially be used to monitor thermal ablation with HIFU. Integrated CT, diagnostic US, and therapeutic focused ultrasound bridges a gap between diagnosis and therapy. Preliminary results show that the multimodality system may represent a relatively inexpensive, accessible, and simple method of both targeting and monitoring HIFU effects. Small animal pre-clinical models may be translated to large

  16. CT and Ultrasound Guided Stereotactic High Intensity Focused Ultrasound (HIFU)

    NASA Astrophysics Data System (ADS)

    Wood, Bradford J.; Yanof, J.; Frenkel, V.; Viswanathan, A.; Dromi, S.; Oh, K.; Kruecker, J.; Bauer, C.; Seip, R.; Kam, A.; Li, K. C. P.

    2006-05-01

    To demonstrate the feasibility of CT and B-mode Ultrasound (US) targeted HIFU, a prototype coaxial focused ultrasound transducer was registered and integrated to a CT scanner. CT and diagnostic ultrasound were used for HIFU targeting and monitoring, with the goals of both thermal ablation and non-thermal enhanced drug delivery. A 1 megahertz coaxial ultrasound transducer was custom fabricated and attached to a passive position-sensing arm and an active six degree-of-freedom robotic arm via a CT stereotactic frame. The outer therapeutic transducer with a 10 cm fixed focal zone was coaxially mounted to an inner diagnostic US transducer (2-4 megahertz, Philips Medical Systems). This coaxial US transducer was connected to a modified commercial focused ultrasound generator (Focus Surgery, Indianapolis, IN) with a maximum total acoustic power of 100 watts. This pre-clinical paradigm was tested for ability to heat tissue in phantoms with monitoring and navigation from CT and live US. The feasibility of navigation via image fusion of CT with other modalities such as PET and MRI was demonstrated. Heated water phantoms were tested for correlation between CT numbers and temperature (for ablation monitoring). The prototype transducer and integrated CT/US imaging system enabled simultaneous multimodality imaging and therapy. Pre-clinical phantom models validated the treatment paradigm and demonstrated integrated multimodality guidance and treatment monitoring. Temperature changes during phantom cooling corresponded to CT number changes. Contrast enhanced or non-enhanced CT numbers may potentially be used to monitor thermal ablation with HIFU. Integrated CT, diagnostic US, and therapeutic focused ultrasound bridges a gap between diagnosis and therapy. Preliminary results show that the multimodality system may represent a relatively inexpensive, accessible, and simple method of both targeting and monitoring HIFU effects. Small animal pre-clinical models may be translated to large

  17. 2011 Mississippi Curriculum Framework: Postsecondary Diagnostic Medical Sonography Technology. (Program CIP: 51.0910 - Diagnostic Medical Sonography/Sonographer and Ultrasound)

    ERIC Educational Resources Information Center

    Finch, Wanda; Wilson, Lesa

    2011-01-01

    As the world economy continues to evolve, businesses and industries must adopt new practices and processes in order to survive. Quality and cost control, work teams and participatory management, and an infusion of technology are transforming the way people work and do business. Employees are now expected to read, write, and communicate…

  18. 2007 Mississippi Curriculum Framework: Postsecondary Diagnostic Medical Sonography Technology. (Program CIP: 51.0910 - Diagnostic Medical Sonography/Sonographer and Ultrasound Technician)

    ERIC Educational Resources Information Center

    Larimore, Crystal; Megginson, Nita; Weekley, Tracy B.

    2007-01-01

    As the world economy continues to evolve, businesses and industries must adopt new practices and processes in order to survive. Quality and cost control, work teams and participatory management, and an infusion of technology are transforming the way people work and do business. Employees are now expected to read, write, and communicate…

  19. Special operator level clinical ultrasound: an experience in application and training.

    PubMed

    Morgan, Andrew R; Vasios, William N; Hubler, David A; Benson, Peter J

    2010-01-01

    Over the past few decades, ultrasound has evolved from a radiology and subspecialist-centric instrument, to a common tool for bedside testing in a variety of specialties. The SOF community is now recognizing the relevancy of training medics to employ this technology for multiple clinical indications in the austere operating environment. In the Fall 2008 issue of Journal of Special Operations Medicine two of the authors described the concept of training SOF medics to employ portable ultrasound as a diagnostic aid. After over two years of concerted effort, the authors trained 29 out of 40 medics of a Special Forces battalion. Retrospective analysis of the quality assurance data for ultrasound studies conducted placed the 109 studies into six categories, allowing inference of trends in clinical indication for ultrasound exams as determined by the SOF medic-ultrasonographer. The resulting distribution suggests that indications for fractures and superficial applications are as prevalent as those for focused abdominal sonography in trauma (FAST) and pneumothorax exams. This analysis focuses on Special Operator Level Clinical Ultrasound (SOLCUS), an ultrasound training curriculum specifically for SOF medics, and helps appropriately prioritize its objectives. Despite the success of this experience, there are several issues requiring resolution before being able to integrate ultrasound training and fielding into the SOF medical armamentarium. PMID:20936599

  20. Task Descriptions in Diagnostic Radiology. Research Report No. 7. Volume 1, Medical Tasks: What the Radiologist Does.

    ERIC Educational Resources Information Center

    Gilpatrick, Eleanor

    The first of four volumes in Research Report No. 7 of the Health Services Mobility Study (HSMS), this book contains 143 task descriptions covering most of the medical activities carried out by diagnostic radiologists. (The work carried out by radiologic technologists, and administrative, machine-related, and nursing-type functions are found in…

  1. Assessment of Factors Affecting the Usefulness and Diagnostic Yield of Core Biopsy Needles with a Side Hole in Endoscopic Ultrasound-Guided Fine-Needle Aspiration

    PubMed Central

    Inoue, Tadahisa; Okumura, Fumihiro; Mizushima, Takashi; Nishie, Hirotada; Iwasaki, Hiroyasu; Anbe, Kaiki; Ozeki, Takanori; Kachi, Kenta; Fukusada, Shigeki; Suzuki, Yuta; Sano, Hitoshi

    2016-01-01

    Background/Aims A barbed puncture needle with a side hole was recently developed to improve sample quality and quantity in endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA). In this study, we retrospectively assessed the usefulness of this puncture needle. Methods Factors affecting diagnostic yield, safety, and diagnostic accuracy were investigated in 76 patients who consecutively underwent EUS-FNA for neoplastic lesions at our hospital between January and December 2013. Results The procedure was successful in all cases; the rates of sample collection and determination of the correct diagnosis were 92.1% and 89.5%, respectively. The mean number of needle passes required for diagnosis was 1.1. Complications included mild intraluminal bleeding in two patients (2.6%). Multivariate analysis revealed that lesion size (≤20 mm) was significantly associated with a decreased chance of determining the correct diagnosis. Conclusions Core biopsy needles with a side hole are safe and provide a satisfactory diagnostic yield. However, the side hole may potentially reduce the rate of making the correct diagnosis in small lesions. PMID:25963081

  2. Design of a Web-tool for diagnostic clinical trials handling medical imaging research.

    PubMed

    Baltasar Sánchez, Alicia; González-Sistal, Angel

    2011-04-01

    New clinical studies in medicine are based on patients and controls using different imaging diagnostic modalities. Medical information systems are not designed for clinical trials employing clinical imaging. Although commercial software and communication systems focus on storage of image data, they are not suitable for storage and mining of new types of quantitative data. We sought to design a Web-tool to support diagnostic clinical trials involving different experts and hospitals or research centres. The image analysis of this project is based on skeletal X-ray imaging. It involves a computerised image method using quantitative analysis of regions of interest in healthy bone and skeletal metastases. The database is implemented with ASP.NET 3.5 and C# technologies for our Web-based application. For data storage, we chose MySQL v.5.0, one of the most popular open source databases. User logins were necessary, and access to patient data was logged for auditing. For security, all data transmissions were carried over encrypted connections. This Web-tool is available to users scattered at different locations; it allows an efficient organisation and storage of data (case report form) and images and allows each user to know precisely what his task is. The advantages of our Web-tool are as follows: (1) sustainability is guaranteed; (2) network locations for collection of data are secured; (3) all clinical information is stored together with the original images and the results derived from processed images and statistical analysis that enable us to perform retrospective studies; (4) changes are easily incorporated because of the modular architecture; and (5) assessment of trial data collected at different sites is centralised to reduce statistical variance. PMID:20517632

  3. Ultrasound skin imaging.

    PubMed

    Alfageme Roldán, F

    2014-12-01

    The interaction of high-frequency ultrasound waves with the skin provides the basis for noninvasive, fast, and accessible diagnostic imaging. This tool is increasingly used in skin cancer and inflammatory conditions as well as in cosmetic dermatology. This article reviews the basic principles of skin ultrasound and its applications in the different areas of dermatology. PMID:24838227

  4. The Value of In Vitro Diagnostic Testing in Medical Practice: A Status Report

    PubMed Central

    Dieterle, Thomas; Giusti, Francesco; Messina, Carlo Guiseppe Mario; Toerien, Eduard; Moch, Holger; Schäfer, Hans Hendrik

    2016-01-01

    Background In vitro diagnostic (IVD) investigations are indispensable for routine patient management. Appropriate testing allows early-stage interventions, reducing late-stage healthcare expenditure (HCE). Aim To investigate HCE on IVDs in two developed markets and to assess the perceived value of IVDs on clinical decision-making. Physician-perceived HCE on IVD was evaluated, as well as desired features of new diagnostic markers. Methods Past and current HCE on IVD was calculated for the US and Germany. A total of 79 US/German oncologists and cardiologists were interviewed to assess the number of cases where: physicians ask for IVDs; IVDs are used for initial diagnosis, treatment monitoring, or post-treatment; and decision-making is based on an IVD test result. A sample of 201 US and German oncologists and cardiologists was questioned regarding the proportion of HCE they believed to be attributable to IVD testing. After disclosing the actual IVD HCE, the physician’s perception of the appropriateness of the amount was captured. Finally, the association between physician-rated impact of IVD on decision-making and perceived contribution of IVD expenditure on overall HCE was assessed. Results IVD costs account for 2.3% and 1.4% of total HCE in the US and Germany. Most physicians (81%) believed that the actual HCE on IVDs was >5%; 19% rated the spending correctly (0–4%, p<0.001). When informed of the actual amount, 64% of physicians rated this as appropriate (p<0.0001); 66% of decision-making was based on IVD. Significantly, more physicians asked for either additional clinical or combined clinical/health economic data than for the product (test/platform) alone (p<0.0001). Conclusions Our results indicate a poor awareness of actual HCE on IVD, but a high attributable value of diagnostic procedures for patient management. New markers should deliver actionable and medically relevant information, to guide decision-making and foster improved patient outcomes. PMID

  5. Prehospital Evaluation of Effusion, Pneumothorax, and Standstill (PEEPS): Point-of-care Ultrasound in Emergency Medical Services

    PubMed Central

    Bhat, Sundeep R.; Johnson, David A.; Pierog, Jessica E.; Zaia, Brita E.; Williams, Sarah R.; Gharahbaghian, Laleh

    2015-01-01

    Introduction In the United States, there are limited studies regarding use of prehospital ultrasound (US) by emergency medical service (EMS) providers. Field diagnosis of life-threatening conditions using US could be of great utility. This study assesses the ability of EMS providers and students to accurately interpret heart and lung US images. Methods We tested certified emergency medical technicians (EMT-B) and paramedics (EMT-P) as well as EMT-B and EMT-P students enrolled in prehospital training programs within two California counties. Participants completed a pre-test of sonographic imaging of normal findings and three pathologic findings: pericardial effusion, pneumothorax, and cardiac standstill. A focused one-hour lecture on emergency US imaging followed. Post-tests were given to all EMS providers immediately following the lecture and to a subgroup one week later. Results We enrolled 57 prehospital providers (19 EMT-B students, 16 EMT-P students, 18 certified EMT-B, and 4 certified EMT-P). The mean pre-test score was 65.2%±12.7% with mean immediate post-test score of 91.1%±7.9% (95% CI [22%–30%], p<0.001). Scores significantly improved for all three pathologic findings. Nineteen subjects took the one-week post-test. Their mean score remained significantly higher: pre-test 65.8%±10.7%; immediate post-test 90.5%±7.0% (95% CI [19%–31%], p<0.001), one-week post-test 93.1%±8.3% (95% CI [21%–34%], p<0.001). Conclusion Using a small sample of EMS providers and students, this study shows the potential feasibility for educating prehospital providers to accurately identify images of pericardial effusion, pneumothorax, and cardiac standstill after a focused lecture. PMID:26265961

  6. Ultrafest: A Novel Approach to Ultrasound in Medical Education Leads to Improvement in Written and Clinical Examinations

    PubMed Central

    Connolly, Kiah; Beier, Lancelot; Langdorf, Mark I.; Anderson, Craig L.; Fox, John C.

    2015-01-01

    Introduction Our objective was to evaluate the effectiveness of hands-on training at a bedside ultrasound (US) symposium (“Ultrafest”) to improve both clinical knowledge and image acquisition skills of medical students. Primary outcome measure was improvement in multiple choice questions on pulmonary or Focused Assessment with Sonography in Trauma (FAST) US knowledge. Secondary outcome was improvement in image acquisition for either pulmonary or FAST. Methods Prospective cohort study of 48 volunteers at “Ultrafest,” a free symposium where students received five contact training hours. Students were evaluated before and after training for proficiency in either pulmonary US or FAST. Proficiency was assessed by clinical knowledge through written multiple-choice exam, and clinical skills through accuracy of image acquisition. We used paired sample t-tests with students as their own controls. Results Pulmonary knowledge scores increased by a mean of 10.1 points (95% CI [8.9–11.3], p<0.00005), from 8.4 to a posttest average of 18.5/21 possible points. The FAST knowledge scores increased by a mean of 7.5 points (95% CI [6.3–8.7] p<0.00005), from 8.1 to a posttest average of 15.6/21. We analyzed clinical skills data on 32 students. The mean score was 1.7 pretest and 4.7 posttest of 12 possible points. Mean improvement was 3.0 points (p<0.00005) overall, 3.3 (p=0.0001) for FAST, and 2.6 (p=0.003) for the pulmonary US exam. Conclusion This study suggests that a symposium on US can improve clinical knowledge, but is limited in achieving image acquisition for pulmonary and FAST US assessments. US training external to official medical school curriculum may augment students’ education. PMID:25671024

  7. Incidence of sepsis following transrectal ultrasound guided prostate biopsy at a tertiary-care medical center in Lebanon

    PubMed Central

    Shahait, Mohammed; Degheili, Jad; El-Merhi, Fadi; Tamim, Hani; Nasr, Rami

    2016-01-01

    ABSTRACT Background Urosepsis is a rare but life-threatening complication following transrectal ultrasound (TRUS) guided needle prostate biopsy. Despite the technological and pharmacological improvements, the problem of bacterial urosepsis after prostate biopsy remains. A strategy for preventing urosepsis following TRUS prostate biopsy in areas with high prevalence of resistant strains or patients presenting risk factors is lacking. Objectives The aim of this study was to assess the prevalence of urosepsis, as well its predictors, following TRUS guided needle biopsy of the prostate in a tertiary care medical center in Lebanon. Materials and Methods We carried out a retrospective study on all patients who underwent TRUS prostate biopsy at the American University of Beirut Medical Center between January 1, 2011 and June 31, 2013. Patients’ hospital charts were reviewed. Data collected included demographic information, pre-procedure disease specific information, as well as post-procedure information. Predictors of urosepsis following TRUS were assessed. Results In total, 265 patients were included in this study, where the prevalence of urosepsis following TRUS prostate biopsy was found to be 9.4%. The significant independent predictors of urosepsis were found to be: age with an OR=0.93 (95% CI: 0.88–1.00, p-value=0.03), and hypertension comorbidity with an OR=3.25 (95% CI: 1.19–8.85, p-value=0.02). Conclusion We found a high prevalence of urosepsis among patients who have undergone TRUS prostate biopsy, and identified two significant risk factors. The results of this study highlight the importance of implementing strategies for prevention of urosepsis following TRUS prostate biopsy. PMID:27136468

  8. Using diffuse near-infrared light to characterize tissue optical and physiologic properties for medical diagnostics

    NASA Astrophysics Data System (ADS)

    Pham, Tuan Hoai

    2001-05-01

    Methods based on near-infrared (NIR) diffuse reflectance offer novel and functional approaches to medical diagnostics. NIR diffuse reflectance techniques are well suited for non-invasive, quantitative characterization of tissue optical properties, namely macroscopic absorption (μa) and reduced scattering (μs') coefficient. Tissue optical properties, in turn, provide unique and clinically relevant functional and structural information about tissues. Needless to say, understanding light- tissue interactions and light transport in multiply scattering (turbid) media is essential in order to fully capitalize on the useful features of NIR diffuse reflectance spectroscopy. This thesis addresses the practical and, to a limited extent, the theoretical issues of NIR diffuse light spectroscopy. The goals of the thesis are two folds: (1)to investigate, from an instrumental and analytical perspectives, the accuracy and limitation of the various diffuse reflectance techniques in quantifying the optical properties of homogenous and layered turbid media, and (2)to evaluate the feasibility and applicability of using NIR diffuse reflectance spectroscopy to quantify in vivo tissue optical and physiologic properties during pathophysiologic processes. With respect to the first objective, we conducted validation studies to assess the accuracy of the frequency-domain and spatially-resolved techniques in quantifying μa and μs' of homogenous turbid media. Similarly, frequency-domain and time-domain approaches were used to characterize the optical properties and thickness of two-layered turbid media. For the second objective, frequency-domain system was used to quantify the changes in the in vivo optical and physiologic properties secondary to cancerous transformation, cardiovascular dysfunction, and photodynamic therapy of tumors. In summary, studies results clearly indicate that NIR diffuse reflectance techniques accurately quantify the in vivo tissue optical and physiologic

  9. Evaluation of the medical diagnostic imaging support system based on 2 years of clinical experience.

    PubMed

    Smith, D V; Smith, S; Bender, G N; Carter, J R; Kim, Y; Cawthon, M A; Leckie, R G; Weiser, J C; Romlein, J; Goeringer, F

    1995-05-01

    The Medical Diagnostic Imaging Support (MDIS) system at Madigan Army Medical Center (MAMC) has been operational in a phased approach since March 1992. Since then, nearly all image acquisition has been digital with progressively increasing primary softcopy diagnosis used. More than 375,000 computed radiography (CR) images as well as other modality images have been archived. Considerable experience in installation and implementation phasing has been gained. The location and ergonomic aspects of equipment placement were refined with time. The original clinical scenario was insufficiently detailed and additions were made to facilitate smoother and more complete transition toward a filmless environment. The MDIS system effectiveness and performance have been good in terms of operational workload throughout, background operations, and reliability. The important areas regarding reliability are image acquisition, output, display, database operations, storage, and the local area network. Fail-safe strategies have been continually improved to maintain continuous clinical image availability during the times when the MDIS system or components malfunction. Many invaluable lessons have been learned for effective quality assurance in a hospital-wide picture archiving and communication system. These issues include training, operational quality control, practical aspects of CR image quality, and increased timeliness in the generation and distribution of radiographic reports. Clinical acceptability has been a continuous process as each phase has been implemented. Clinical physicians quickly used the workstations soon after the start of MDIS at MAMC. The major advantage for clinicians has been the amount of time saved when retrieving multimodality images for review. On the other hand, the radiologists have been slower in their acceptance of the workstation for routine use.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7612705

  10. Opto-acoustic diagnostics of the thermal action of high-intensity focused ultrasound on biological tissues: the possibility of its applications and model experiments

    SciTech Connect

    Khokhlova, Tanya D; Pelivanov, Ivan M; Solomatin, Vladimir S; Karabutov, Aleksander A; Sapozhnikov, Oleg A

    2006-12-31

    The possibility of using the opto-acoustic (OA) method for monitoring high-intensity ultrasonic therapy is studied. The optical properties of raw and boiled liver samples used as the undamaged model tissue and tissue destroyed by ultrasound, respectively, are measured. Experiments are performed with samples consisting of several alternating layers of raw and boiled liver of different thickness. The position and transverse size of the thermal lesion were determined from the temporal shape of the OA signals. The results of measurements are compared with the real size and position of the thermal lesion determined from the subsequent cuts of the sample. It is shown that the OA method permits the diagnostics of variations in biological tissues upon ultrasonic therapy. (special issue devoted to multiple radiation scattering in random media)

  11. Justification of diagnostic medical exposures: some practical issues. Report of an International Atomic Energy Agency Consultation

    PubMed Central

    Malone, J; Guleria, R; Craven, C; Horton, P; Järvinen, H; Mayo, J; O’reilly, G; Picano, E; Remedios, D; Le Heron, J; Rehani, M; Holmberg, O; Czarwinski, R

    2012-01-01

    Objectives The Radiation Protection of Patients Unit of the International Atomic Energy Agency (IAEA) is concerned about the effectiveness of justification of diagnostic medical exposures. Recent published work and the report of an initial IAEA consultation in the area gave grounds for such concerns. There is a significant level of inappropriate usage, and, in some cases, a poor level of awareness of dose and risk among some key groups involved. This article aims to address this. Methods The IAEA convened a second group of experts in November 2008 to review practical and achievable actions that might lead to more effective justification. Results This report summarises the matters that this group considered and the outcome of their deliberations. There is a need for improved communication, both within professions and between professionals on one hand, and between professionals and the patients/public on the other. Coupled with this, the issue of consent to imaging procedures was revisited. The need for good evidence-based referral guidelines or criteria of acceptability was emphasised, as was the need for their global adaptation and dissemination. Conclusion Clinical audit was regarded as a key tool in ensuring that justification becomes an effective, transparent and accountable part of normal radiological practice. In summary, justification would be facilitated by the “3 As”: awareness, appropriateness and audit. PMID:21343316

  12. Development and use of analytical quality specifications in the in vitro diagnostics medical device industry.

    PubMed

    Powers, D M; Greenberg, N

    1999-11-01

    Manufacturers of in vitro diagnostic (IVD) medical devices have become integral partners with their customers in determining the quality of laboratory results. Design controls imposed by ISO 9001 quality system standards and various regulations require manufacturers to implement a formal design process, which begins and ends with customer requirements. For IVD systems, this means that manufacturers must establish analytical quality specifications as part of their design input. This provides greater assurance that commercial products will satisfy customer requirements. In the case of quantitative IVD measurement systems, analytical quality specifications include total allowable uncertainty (bias, imprecision, non-specificity). The primary source of customer requirements is the laboratory-customer, who should have established analytical quality specifications based on the needs of its physician-clients. The total allowable uncertainty budget is allocated in the design process to the individual components of the system, such as reagents, instrumentation, calibrators and accessories, and to other factors such as operator, specimen and environmental interactions. Their performance must collectively meet the total allowable uncertainty specification when they are finally integrated into a measurement system. The design control model requires objective evidence that design specifications have been met (verification) and, finally, that the system will satisfy the needs of its intended users (validation). Compliance with the quality system standards is monitored through independent audits, government inspections and post-market surveillance. PMID:10667695

  13. Authentication and recovery of medical diagnostic image using dual reversible digital watermarking.

    PubMed

    Deng, Xiaohong; Chen, Zhigang; Zeng, Feng; Zhang, Yaoping; Mao, Yimin

    2013-03-01

    This paper proposes a new region-based tampering detection and recovering method that utilizes both reversible digital watermarking and quad-tree decomposition for medical diagnostic image's authentication. Firstly, the quad-tree decomposition is used to divide the original image into blocks with high homogeneity, and then we computer pixels' linear interpolation as each block's recovery feature. Secondly, these recovery features as the first layer watermarking information is embedded by using simple invertible integer transformation. In order to enhance the proposed method's security, the logistic chaotic map is exploited to choose each block's reference pixel. The second layer watermark comprises by the quad-tree information and essential parameters for extraction are embedded by LSB replacement. In the authentication phase, the embedded watermark is extracted and the source image is recovered, and the similar linear interpolation technique is utilized to get each block's feature. Therefore, the tampering detection and localization can be achieved through comparing the extracted feature with the recomputed one, and the extracted feature can be used to recover those tampered regions with high similarity to their original state. Experimental results show that, compared with previous similar existing scheme, the proposed method not only achieves high embedding capacity and good visual quality of marked and restored image, but also has more accuracy for tampering detection. PMID:23755652

  14. Sounding out the future of ultrasound education

    PubMed Central

    Dawson, M; Goudie, A; Mallin, M

    2014-01-01

    As in so many other fields, the internet has revolutionised medical education. It has done this by circumventing the traditional constraints of medical education, in particular the availability of local resources such as teachers and textbooks. This “education revolution” has been most successful in the areas of theoretical knowledge. This article explores the available resources, and the challenges that arise when attempting to teach point-of-care ultrasound via the internet, such as the visuomotor and visuospatial skills required to create a diagnostic image. This article also describes the progress to date in this field. PMID:27433235

  15. The Technologist Function in Fields Related to Radiology: Tasks in Radiation Therapy and Diagnostic Ultrasound. Research Report No. 9; Relating Technologist Tasks in Diagnostic Radiology, Ultrasound and Radiation Therapy. Research Report No. 10.

    ERIC Educational Resources Information Center

    Gilpatrick, Eleanor

    The two research reports included in this document describe the application of the Health Services Mobility Study (HSMS) task analysis method to two technologist functions and examine the interrelationships of these tasks with those in diagnostic radiology. (The HSMS method includes processes for using the data for designing job ladders, for…

  16. TOPICAL REVIEW: Synthesis and applications of magnetic nanoparticles for biorecognition and point of care medical diagnostics

    NASA Astrophysics Data System (ADS)

    Sandhu, Adarsh; Handa, Hiroshi; Abe, Masanori

    2010-11-01

    Functionalized magnetic nanoparticles are important components in biorecognition and medical diagnostics. Here, we present a review of our contribution to this interdisciplinary research field. We start by describing a simple one-step process for the synthesis of highly uniform ferrite nanoparticles (d = 20-200 nm) and their functionalization with amino acids via carboxyl groups. For real-world applications, we used admicellar polymerization to produce 200 nm diameter 'FG beads', consisting of several 40 nm diameter ferrite nanoparticles encapsulated in a co-polymer of styrene and glycidyl methacrylate for high throughput molecular screening. The highly dispersive FG beads were functionalized with an ethylene glycol diglycidyl ether spacer and used for affinity purification of methotrexate—an anti-cancer agent. We synthesized sub-100 nm diameter magnetic nanocapsules by exploiting the self-assembly of viral capsid protein pentamers, where single 8, 20, and 27 nm nanoparticles were encapsulated with VP1 pentamers for applications including MRI contrast agents. The FG beads are now commercially available for use in fully automated bio-screening systems. We also incorporated europium complexes inside a polymer matrix to produce 140 nm diameter fluorescent-ferrite beads (FF beads), which emit at 618 nm. These FF beads were used for immunofluorescent staining for diagnosis of cancer metastases to lymph nodes during cancer resection surgery by labeling tumor cell epidermal growth factor receptor (EGFRs), and for the detection of brain natriuretic peptide (BNP)—a hormone secreted in excess amounts by the heart when stressed—to a level of 2.0 pg ml - 1. We also describe our work on Hall biosensors made using InSb and GaAs/InGaAs/AlGaAs 2DEG heterostructures integrated with gold current strips to reduce measurement times. Our approach for the detection of sub-200 nm magnetic bead is also described: we exploit the magnetically induced capture of micrometer sized 'probe

  17. Focal bowel wall changes detected with colour Doppler ultrasound: diagnostic value in acute non-diverticular diseases of the colon.

    PubMed

    Danse, E M; Jamart, J; Hoang, P; Laterre, P F; Kartheuser, A; Van Beers, B E

    2004-11-01

    We performed a study to determine if colour Doppler findings may help to identify the cause of wall thickening in acute non-diverticular diseases of the colon. The study group included 66 patients admitted to the emergency department with a final diagnosis of infectious colitis (n=23), inflammatory colitis (n=10), ischaemic colitis (n=23) and malignant tumours (n=10). The following ultrasound features were assessed: maximal wall thickness, wall stratification, arterial flow in the colonic wall and arteriolar resistive index. Higher values of wall thickness were observed in malignant tumour (18.2+/-6.2 mm, p<0.001). Moderately thickened wall (6.6+/-1.3 mm, p< or =0.06), preserved stratification (90% versus 46% in the remainder of the study population) and lower resistive index (0.51+/-0.10, p< or =0.05) were significantly related to inflammatory colitis. Absence of arterial flow was more frequently observed in ischaemia (43% versus 12% in the remainder of the study population). In conclusion, despite some overlap, both ultrasound and colour Doppler features are helpful in the differential diagnosis of colonic thickening related to non-diverticular colonic lesions. PMID:15507414

  18. Ultrasound applications in mass casualties and extreme environments.

    PubMed

    Ma, O John; Norvell, Jeffrey G; Subramanian, Srikala

    2007-05-01

    A mass-casualty incident is one in which the number of patients with injuries exceeds the available medical resources to care for them in a timely manner. In such a situation, the numerous advantages of ultrasonography make it an ideal triage tool for helping clinicians rapidly screen patients. Experiences during the 1988 Armenian earthquake and the 1999 Turkish earthquake demonstrated the proficiency of ultrasound in providing rapid clinical data to the physicians caring for the mass-casualty patients. Wireless and satellite transmission of ultrasound images also has been shown to be feasible and may be applied to mass-casualty situations. In addition, ultrasound applications have been demonstrated to aid in the diagnosis of various conditions, including pneumothorax, in the International Space Station. Ultrasound's portability, reproducibility, accuracy, and ease of use will make it an important diagnostic instrument for future space missions. PMID:17446788

  19. Wavelet-based ultrasound image denoising: performance analysis and comparison.

    PubMed

    Rizi, F Yousefi; Noubari, H Ahmadi; Setarehdan, S K

    2011-01-01

    Ultrasound images are generally affected by multiplicative speckle noise, which is mainly due to the coherent nature of the scattering phenomenon. Speckle noise filtering is thus a critical pre-processing step in medical ultrasound imaging provided that the diagnostic features of interest are not lost. A comparative study of the performance of alternative wavelet based ultrasound image denoising methods is presented in this article. In particular, the contourlet and curvelet techniques with dual tree complex and real and double density wavelet transform denoising methods were applied to real ultrasound images and results were quantitatively compared. The results show that curvelet-based method performs superior as compared to other methods and can effectively reduce most of the speckle noise content of a given image. PMID:22255196

  20. Radiative-SPR platform for the detection of apolipoprotein E for use in medical diagnostics

    NASA Astrophysics Data System (ADS)

    Sciacca, Beniamino; Francois, Alexandre; Penno, Megan A. S.; Brazzatti, Julie A.; Klingler-Hoffmann, Manuela; Hoffmann, Peter; Monro, Tanya M.

    2012-03-01

    Surface Plasmon Resonance (SPR) based sensors enable the rapid, label-free and highly sensitive detection of a large range of biomolecules. We have previously shown that, using silver coated optical fibres with an high surface roughness, a re-scattering of the surface plasmons is possible, turning SPR into a radiative process. This approach overcomes limitations associated with current SPR technologies such as the tight tolerance on the metallic coating thickness, and results in a more compact, versatile, robust and cost-effective approach. However, the specific detection of small molecules is a challenge in SPR systems, regardless of the SPR architecture that is used. This new sensing platform, which has proved effective for the detection of large molecules such as viruses, is now demonstrated to be able to detect small proteins thanks to an improved surface functionalization procedure, a key point for reliable and robust immunosensors. Avidin, a tetrameric biotin-binding protein, was used to link biotinylated antibodies to the biotinylated surface, with a given orientation, to enable efficient sensing of the analyte. This approach may offer significant advantages compared to protein A surface functionalization strategies such as a limited cross reactivity with free IgG antibodies in clinical samples. We demonstrate that by bringing together this novel emission-based fibre SPR platform, with an improved surface functionalization process, is possible to rapidly and specifically detect human apolipoprotein E, a low molecular weight protein (~39kDa) known to be involved in cardiovascular diseases, in Alzheimer's disease and in gastric cancer. The results obtained clearly show that this new sensing platform has the potential to serve as a tool for point-of-decision medical diagnostics.

  1. Parameterized algorithms for quantitative differentials in spectrally equivalent medical diagnostic x-ray beams.

    PubMed

    Okunade, Akintunde Akangbe

    2005-06-01

    Qualitative and quantitative equivalence of spectra transmitted by two different elemental filters require a good match in terms of shape and size over the entire energy range of 0-150 keV used in medical diagnostic radiology. However, the photoelectric absorptions and Compton scattering involved in the interaction of x rays with matter at these relatively low photon energies differ in a nonuniform manner with energy and atomic number. By careful choice of thicknesses for filter materials with an atomic number between 12 and 39, when compared with aluminum, it is possible to obtain transmitted beams of the same shape (quality) but not of the same size (quantity). In this paper, calculations have been carried out for the matching of the shapes and sizes of beams transmitted through specified thicknesses of aluminium filter and spectrally equivalent thicknesses of other filter materials (different from aluminium) using FORTRAN source codes traceable to the American Association of Physics in Medicine (AAPM), College Park, MD, USA. Parametrized algorithms for the evaluation of quantitative differentials (deficit or surplus) in radiation output (namely, photon fluence, exposure, kerma, energy imparted, absorbed dose, and effective dose) from these transmitted spectrally equivalent beams were developed. These differentials range between 1%, and 4% at 1 mm Al filtration and between 8%, and 25% for filtration of 6 mm Al for different filter materials in comparison with aluminum. Also developed were models for factors for converting measures of photon fluence, exposure-area product, (EAP), and kerma-area product (KAP) to risk related quantities such as energy imparted, absorbed dose, and effective dose from the spectrally equivalent beams. The thicknesses of other filter materials that are spectrally equivalent to given thicknesses of aluminum filter were characterized using polynomial functions. The fact that the use of equivalent spectra in radiological practice can

  2. Organ Doses From Diagnostic Medical Radiography-Trends Over Eight Decades (1930 to 2010).

    PubMed

    Melo, Dunstana R; Miller, Donald L; Chang, Lienard; Moroz, Brian; Linet, Martha S; Simon, Steven L

    2016-09-01

    This study provides a retrospective assessment of doses to 13 organs for the most common radiographic examinations conducted between the 1930s and 2010, taking into account typical technical parameters used for radiography during those years. This study is intended to be a resource on changes in medical diagnostic radiation exposure over time with a specific purpose of supporting retrospective epidemiological studies of radiation health risks. The authors derived organ doses to the brain, esophagus, thyroid, red bone marrow, lungs, breast, heart, stomach, liver, colon, urinary bladder, ovaries, and testes based on 14 common radiographic procedures and compared, when possible, with doses reported in the literature. These dose estimates were based on radiographic exposure parameters described in textbooks widely used by radiologic technologists in training from 1939 to 2010. The derived estimated doses presented here are believed to be representative of typical organs for an average-size adult who might be considered to be similar to the reference person. There were large variations in organ doses noted among the different types of radiographic examinations. Doses were highest in organs within the area imaged and next highest in organs in close proximity to the area imaged. Estimated organ doses have declined substantially [overall 22-fold (±38)] over time as a consequence of changes in technology, imaging protocols and protective measures. For some examinations, only slight differences were observed in doses for the decades of the 1960s, 1970s, and 1980s due to minor changes in technical parameters. Substantial dose reductions were observed in the 1990s and 2000s. PMID:27472750

  3. Parameterized algorithms for quantitative differentials in spectrally equivalent medical diagnostic x-ray beams

    SciTech Connect

    Okunade, Akintunde Akangbe

    2005-06-15

    Qualitative and quantitative equivalence of spectra transmitted by two different elemental filters require a good match in terms of shape and size over the entire energy range of 0-150 keV used in medical diagnostic radiology. However, the photoelectric absorptions and Compton scattering involved in the interaction of x rays with matter at these relatively low photon energies differ in a nonuniform manner with energy and atomic number. By careful choice of thicknesses for filter materials with an atomic number between 12 and 39, when compared with aluminum, it is possible to obtain transmitted beams of the same shape (quality) but not of the same size (quantity). In this paper, calculations have been carried out for the matching of the shapes and sizes of beams transmitted through specified thicknesses of aluminium filter and spectrally equivalent thicknesses of other filter materials (different from aluminium) using FORTRAN source codes traceable to the American Association of Physics in Medicine (AAPM), College Park, MD, USA. Parametrized algorithms for the evaluation of quantitative differentials (deficit or surplus) in radiation output (namely, photon fluence, exposure, kerma, energy imparted, absorbed dose, and effective dose) from these transmitted spectrally equivalent beams were developed. These differentials range between 1%, and 4% at 1 mm Al filtration and between 8%, and 25% for filtration of 6 mm Al for different filter materials in comparison with aluminum. Also developed were models for factors for converting measures of photon fluence, exposure-area product, (EAP), and kerma-area product (KAP) to risk related quantities such as energy imparted, absorbed dose, and effective dose from the spectrally equivalent beams. The thicknesses of other filter materials that are spectrally equivalent to given thicknesses of aluminum filter were characterized using polynomial functions. The fact that the use of equivalent spectra in radiological practice can

  4. Clinically Unjustified Diagnostic Imaging – a Worrisome Tendency in Today’s Medical Practice

    PubMed Central

    Sobiecka, Aleksandra; Bekiesińska-Figatowska, Monika; Rutkowska, Milena; Latos, Tomasz; Walecki, Jerzy

    2016-01-01

    Summary Background The purpose of the study was to evaluate the percentage of unjustified examinations among all the CT and MRI studies performed by two radiology departments and to determine the types of examinations which are most commonly carried out unnecessarily. Material/Methods Three radiologists assessed the justification of CT and MRI examinations performed during a period of 14 days based on the referrals. The radiologists assessed 799 referrals for CT scans (847 examinations of a particular part of the body) and 269 MRI referrals (269 examinations). The criteria for justification were: medical expertise and the guidelines. During the first stage radiologists divided the examinations into 3 groups: justified, unjustified and the examinations of questionable justification. The second step was to determine the reasons why the studies were considered as unjustified or of questionable justification. Results 73 of 1116 examinations (6.54%) were considered to be unjustified or of a questionable justification. There were 59 CT scans (59/847=6.97%) and 14 MRI studies (14/269=5.20%). The most common reasons to consider them as unjustified or of questionable justification were: inadequate method of diagnostic imaging chosen as a first-line tool and lacking or insufficient clinical details. Conclusions In our investigation 6.54% of both CT and MRI examinations were considered as unjustified or of questionable justification, which is lower than described in other studies (from 7% to 26%). The assessment was based only on referrals, therefore a total share of these examinations is likely to be higher. PMID:27471577

  5. In vitro diagnostic company recalls and medical laboratory practices: an Italian case

    PubMed Central

    Lippi, Giuseppe; Salvagno, Gian Luca; Brocco, Giorgio; Guidi, Gian Cesare

    2015-01-01

    Introduction In vitro human diagnostic (IVD) company recalls are a common practice aimed to either minimize a potential error or eliminate an existing failure. In this case report, we aim to provide a critical analysis of a recent IVD recall and to provide a practical framework about what to do when an IVD company recalls product(s) based on the International Organization for Standardization - ISO 15189:2012 standard. Case report In 2014, Abbott Laboratories® (Green Oaks, IL) published an urgent field safety notice regarding a product recall (Architect Intact parathyroid hormone (PTH) Assay List Number 8K25) with immediate action required. The IVD company explained the reasons for the recall as follows: i) Abbott has confirmed that a performance shift in the Architect Intact PTH assay has the potential to generate falsely elevated results on patient samples; ii) results generated with impacted lots may demonstrate a positive shift relative to those generated with previous reagent and/or calibrator lots. This issue may also impact established Architect Intact PTH reference ranges; iii) the magnitude of shift averages approximately 13% to 45%; iv) Abbott Architect Intact PTH controls do not detect the shift; and v) all current reagent, calibrator, and control inventory are impacted. The recall could have resulted in ~40,000 inaccurate laboratory tests reported by 18 laboratories from Italy (Lombardy region). Conclusion IVD company recalls have a serious impact on the patient safety and require a thorough investigation and responsible approach to minimize the possible damage. Medical laboratories accredited according to the ISO 15189 standard have procedures in place to manage such situations and ensure that patient safety is maintained when such recalls are issued. PMID:26110040

  6. The impact of using musculoskeletal ultrasound imaging and other influencing factors on medication adherence in patients with rheumatoid arthritis: a qualitative study

    PubMed Central

    Kumar, Kanta; Raza, Karim; Gill, Paramjit; Greenfield, Sheila

    2016-01-01

    Background Medication can ease symptoms and limit disease progression in rheumatoid arthritis (RA). Despite this, nonadherence to medication is common in RA. We explored the determinants of high and low adherence to disease-modifying antirheumatic drugs (DMARDs) in patients with RA and provide suggestions on approaches to improving adherence to DMARDs. Methods Patients with RA were identified from those who had previously participated in a questionnaire measuring levels of medication adherence. Twenty patients participated (ten high and ten low adherers, as determined by responses to the Medication Adherence Report Scale). In-depth individual semistructured interviews were undertaken until data saturation was reached. Interviews were transcribed and analyzed using a constant comparative method. Results Four main themes related to adherence were identified: 1) symptom severity; 2) illness perception; 3) perceived benefits and risks of DMARDs; and 4) the quality and quantity of information about RA and DMARDs. In addition, patients’ suggestions about strategies to optimize adherence to DMARDs were captured and they fell within the following themes: 1) musculoskeletal ultrasound to explain the disease process and to provide objective feedback about the extent to which their disease activity is being effectively controlled; 2) better explanations of the consequences of poorly controlled RA; and 3) a good relationship with the health professional. Conclusion Patients’ beliefs about medicines, perceptions about RA, and level of satisfaction with information about DMARDs influenced their adherence to DMARDs. The use of musculoskeletal ultrasound to image the inflamed joint may help to improve patient adherence to DMARDs. PMID:27366054

  7. [One third of Danish doctors specializing in diagnostic radiology do not feel sufficiently equipped in terms of medical expertise].

    PubMed

    Lange, Benedicte; Carlsen, Charlotte Green; Jurik, Anne Grethe

    2014-02-01

    An internet-based survey among Danish doctors specializing in diagnostic radiology revealed differences with respect to the length of internships at regional and university hospitals as well as the educational environment. The university hospitals were generally evaluated to have the best educational facilities except within practical skills. Therefore, it seems necessary to optimize the educational environment at regional hospitals, especially within medical expertise and scientific skills which are key elements regarding continuous development and quality assurance within radiology. PMID:25347440

  8. Improved cardiovascular diagnostic accuracy by pocket size imaging device in non-cardiologic outpatients: the NaUSiCa (Naples Ultrasound Stethoscope in Cardiology) study

    PubMed Central

    2010-01-01

    Miniaturization has evolved in the creation of a pocket-size imaging device which can be utilized as an ultrasound stethoscope. This study assessed the additional diagnostic power of pocket size device by both experts operators and trainees in comparison with physical examination and its appropriateness of use in comparison with standard echo machine in a non-cardiologic population. Three hundred four consecutive non cardiologic outpatients underwent a sequential assessment including physical examination, pocket size imaging device and standard Doppler-echo exam. Pocket size device was used by both expert operators and trainees (who received specific training before the beginning of the study). All the operators were requested to give only visual, qualitative insights on specific issues. All standard Doppler-echo exams were performed by expert operators. One hundred two pocket size device exams were performed by experts and two hundred two by trainees. The time duration of the pocket size device exam was 304 ± 117 sec. Diagnosis of cardiac abnormalities was made in 38.2% of cases by physical examination and in 69.7% of cases by physical examination + pocket size device (additional diagnostic power = 31.5%, p < 0.0001). The overall K between pocket size device and standard Doppler-echo was 0.67 in the pooled population (0.84 by experts and 0.58 by trainees). K was suboptimal for trainees in the eyeball evaluation of ejection fraction, left atrial dilation and right ventricular dilation. Overall sensitivity was 91% and specificity 76%. Sensitivity and specificity were lower in trainees than in experts. In conclusion, pocket size device showed a relevant additional diagnostic value in comparison with physical examination. Sensitivity and specificity were good in experts and suboptimal in trainees. Specificity was particularly influenced by the level of experience. Training programs are needed for pocket size device users. PMID:21110840

  9. Two-layer Lab-on-a-chip (LOC) with passive capillary valves for mHealth medical diagnostics.

    PubMed

    Balsam, Joshua; Bruck, Hugh Alan; Rasooly, Avraham

    2015-01-01

    There is a new potential to address needs for medical diagnostics in Point-of-Care (PoC) applications using mHealth (Mobile computing, medical sensors, and communications technologies for health care), a mHealth based lab test will require a LOC to perform clinical analysis. In this work, we describe the design of a simple Lab-on-a-chip (LOC) platform for mHealth medical diagnostics. The LOC utilizes a passive capillary valve with no moving parts for fluid control using channels with very low aspect ratios cross sections (i.e., channel width ≫ height) achieved through transitions in the channel geometry via that arrest capillary flow. Using a CO2 laser in raster engraving mode, we have designed and fabricated an eight-channel LOC for fluorescence signal detection fabricated by engraving and combining just two polymer layers. Each of the LOC channels is capable of mixing two reagents (e.g., enzyme and substrate) for various assays. For mHealth detection, we used a mobile CCD detector equipped with LED multispectral illumination in the red, green, blue, and white range. This technology enables the development of low-cost LOC platforms for mHealth whose fabrication is compatible with standard industrial plastic fabrication processes to enable mass production of mHealth diagnostic devices, which may broaden the use of LOCs in PoC applications, especially in global health settings. PMID:25626544

  10. Intravascular ultrasound

    MedlinePlus

    IVUS; Ultrasound - coronary artery; Endovascular ultrasound; Intravascular echocardiography ... A tiny ultrasound wand is attached to the top of a thin tube called a catheter. This ultrasound catheter is inserted ...

  11. Duplex ultrasound

    MedlinePlus

    ... ultrasound with Doppler ultrasound . Traditional ultrasound uses sound waves that bounce off blood vessels to create pictures. Doppler ultrasound records sound waves reflecting off moving objects, such as blood, to ...

  12. A Two-Criterion Model for Microvascular Bio-Effects Induced In Vivo by Contrast Microbubbles Exposed to Medical Ultrasound.

    PubMed

    Church, Charles C; Miller, Douglas L

    2016-06-01

    The mechanical index (MI) is a theoretical exposure parameter for cavitational bio-effects of diagnostic ultrasound. The theory for the MI assumed that bubbles of all relevant sizes exist in tissue, a condition that is approximated for tissues that include a microbubble contrast agent. Therefore, the MI should allow science-based safety guidance for contrast-enhanced diagnostic ultrasound. However, theoretical predictions of bio-effects thresholds based on the MI typically do not concur with the frequency dependence of experimentally measured thresholds for bio-effects. For example, experimental thresholds for glomerular capillary hemorrhage in rats infused with contrast microbubbles increased approximately linearly with frequency, whereas the MI predicted a square root dependence. Here, cavitation thresholds were computed for linear versions of the acoustic pulses used in that study assuming bubbles containing either air, C3F8, or a 1:1 mixture of the two and surrounded by either blood or kidney tissue. Although no single threshold criterion was successful, combining results for one criterion that maximized circumferential stress in the capillary wall with another that ensured an inertial collapse produced thresholds that were consistent with experimental data. This suggests that a contrast-specific safety metric may be achieved following validation of this two-criterion model. PMID:27033330

  13. Nonlinear acoustics in biomedical ultrasound

    NASA Astrophysics Data System (ADS)

    Cleveland, Robin O.

    2015-10-01

    Ultrasound is widely used to image inside the body; it is also used therapeutically to treat certain medical conditions. In both imaging and therapy applications the amplitudes employed in biomedical ultrasound are often high enough that nonlinear acoustic effects are present in the propagation: the effects have the potential to be advantageous in some scenarios but a hindrance in others. In the case of ultrasound imaging the nonlinearity produces higher harmonics that result in images of greater quality. However, nonlinear effects interfere with the imaging of ultrasound contrast agents (typically micron sized bubbles with a strong nonlinear response of their own) and nonlinear effects also result in complications when derating of pressure measurements in water to in situ values in tissue. High intensity focused ultrasound (HIFU) is emerging as a non-invasive therapeutic modality which can result in thermal ablation of tissue. For thermal ablation, the extra effective attenuation resulting from nonlinear effects can result in enhanced heating of tissue if shock formation occurs in the target region for ablation - a highly desirable effect. However, if nonlinearity is too strong it can also result in undesired near-field heating and reduced ablation in the target region. The disruption of tissue (histotripsy) and fragmentation of kidney stones (lithotripsy) exploits shock waves to produce mechanically based effects, with minimal heating present. In these scenarios it is necessary for the waves to be of sufficient amplitude that a shock exists when the waveform reaches the target region. This talk will discuss how underlying nonlinear phenomenon act in all the diagnostic and therapeutic applications described above.

  14. Developing an automated database for monitoring ultrasound- and computed tomography-guided procedure complications and diagnostic yield.

    PubMed

    Itri, Jason N; Jones, Lisa P; Kim, Woojin; Boonn, William W; Kolansky, Ana S; Hilton, Susan; Zafar, Hanna M

    2014-04-01

    Monitoring complications and diagnostic yield for image-guided procedures is an important component of maintaining high quality patient care promoted by professional societies in radiology and accreditation organizations such as the American College of Radiology (ACR) and Joint Commission. These outcome metrics can be used as part of a comprehensive quality assurance/quality improvement program to reduce variation in clinical practice, provide opportunities to engage in practice quality improvement, and contribute to developing national benchmarks and standards. The purpose of this article is to describe the development and successful implementation of an automated web-based software application to monitor procedural outcomes for US- and CT-guided procedures in an academic radiology department. The open source tools PHP: Hypertext Preprocessor (PHP) and MySQL were used to extract relevant procedural information from the Radiology Information System (RIS), auto-populate the procedure log database, and develop a user interface that generates real-time reports of complication rates and diagnostic yield by site and by operator. Utilizing structured radiology report templates resulted in significantly improved accuracy of information auto-populated from radiology reports, as well as greater compliance with manual data entry. An automated web-based procedure log database is an effective tool to reliably track complication rates and diagnostic yield for US- and CT-guided procedures performed in a radiology department. PMID:24146357

  15. Evidence of Second-Order Factor Structure in a Diagnostic Problem Space: Implications for Medical Education.

    ERIC Educational Resources Information Center

    Papa, Frank J.; And Others

    1997-01-01

    Chest pain was identified as a specific medical problem space, and disease classes were modeled to define it. Results from a test taken by 628 medical residents indicate a second-order factor structure that suggests that chest pain is a multidimensional problem space. Implications for medical education are discussed. (SLD)

  16. Potentialities for Learning in Medical Students' Ways of Approaching a Diagnostic Task

    ERIC Educational Resources Information Center

    Bonnevier, Anna; Josephson, Anna; Scheja, Max

    2012-01-01

    The study investigates medical students' ways of approaching a medical task. Fourteen medical students in their clinical years responded to a written patient case on chest pain. Variations in the students' responses to the task were analysed from a contextual and linguistic perspective. Students approached the task in two distinctly different…

  17. Histological Knowledge as a Predictor of Medical Students' Performance in Diagnostic Pathology

    ERIC Educational Resources Information Center

    Nivala, Markus; Lehtinen, Erno; Helle, Laura; Kronqvist, Pauliina; Paranko, Jorma; Säljö, Roger

    2013-01-01

    Over the years, the role and extent of the basic sciences in medical curricula have been challenged by research on clinical expertise, clinical teachers, and medical students, as well as by the development and diversification of the medical curricula themselves. The aim of this study was to examine how prior knowledge of basic histology and…

  18. Assessment of Diagnostic Accuracy and Efficiency of Categories 4 and 5 of the Second Edition of the BI-RADS Ultrasound Lexicon in Diagnosing Breast Lesions.

    PubMed

    Zou, Xuebin; Wang, Jianwei; Lan, Xiaowen; Lin, Qingguang; Han, Feng; Liu, Longzhong; Li, Anhua

    2016-09-01

    The purpose of this study was to evaluate the diagnostic accuracy and efficiency of categories 4 and 5 of the second edition of the Breast Imaging Reporting and Data System (BI-RADS) ultrasound (US) lexicon in diagnosing breast lesions. In our retrospective study, 579 lesions in 544 patients were assessed by US as the preliminary diagnosis and classified in subcategories 4a-4c and category 5 based on the second edition of the BI-RADS US lexicon with some obvious changes, such as the redefined margin, new calcification type, associated features and some special cases. Inter-observer agreement was determined. Ultrasound results were compared with the pathologic results for confirmation. Positive predictive values (PPVs) of subcategories 4a-4c were compared with theoretical values using the χ(2) test; the binomial test was used for category 5 lesions. Of the 579 lesions, 212 were confirmed as benign (36.61%), and the remaining 367 lesions were confirmed as borderline/malignant (63.39%). Inter-observer agreement was moderate for subcategories 4a-4c (κ = 0.52), moderate for subcategories 4a-4c and category 5 (κ = 0.56) and substantial for categories 4 and 5 (κ = 0.67). The PPVs for subcategories 4a-4c were 23.74%, 70.67% and 81.25%, respectively. In addition, the total PPV for category 4 was 46.92% (183/390), and the total PPV for category 5 was 97.35% (184/189). Statistical results revealed that the PPVs of subcategories 4a and 4b differed significantly from the theoretical values (p < 0.05); the PPVs of subcategory 4c and category 5 were significantly correlated with the theoretical PPVs (p > 0.05). In conclusion, subcategories 4a and 4b have lower diagnostic efficiency than subcategory 4c and category 5. Inter-observer agreement for subcategories 4a-4c remains to be improved. The most common features of subcategories 4a-4c differ, but overlap. It is recommended that inexperienced doctors in primary hospitals not classify lesions into subcategories in

  19. The sensitivity of medical diagnostic decision-support knowledge bases in delineating appropriate terms to document in the medical record.

    PubMed Central

    Feldman, M. J.; Barnett, G. O.; Morgan, M. M.

    1991-01-01

    A pertinent, legible and complete medical record facilitates good patient care. The recording of the symptoms, signs and lab findings which are relevant to a patient's condition contributes importantly to the medical record. The consideration and documentation of other disease states known to be related to the patient's primary illness provide further enhancement. We propose that developing sets of disease-specific core elements which a physician may want to document in the medical record can have many benefits. We hypothesize that for a given disease, terms with high importance (TI) and frequency (TF) in the DX-plain, QMR and Iliad knowledge bases (KBs) are terms which are used commonly in the medical record, and may be, in fact, terms which physicians would find useful to document. A study was undertaken to validate ten such sets of disease-specific core elements. For each of ten prevalent diseases, high TI and TF terms from the three KBs mentioned were pooled to derive the set of core elements. For each disease, all patient records (range 385 to 16,972) from a computerized ambulatory medical record database were searched to document the actual use by physicians of each of these core elements. A significant percentage (range 50 to 86%) of each set of core elements was confirmed as being used by the physicians. In addition, all medical concepts from a selection of full text records were identified, and an average of 65% of the concepts were found to be core elements.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1807600

  20. Design, construction, and validation of a rotary multifunctional intravascular diagnostic catheter combining multispectral fluorescence lifetime imaging and intravascular ultrasound

    PubMed Central

    Bec, Julien; Xie, Hongtao; Yankelevich, Diego R.; Zhou, Feifei; Sun, Yang; Ghata, Narugopal; Aldredge, Ralph

    2012-01-01

    Abstract. We report the development and validation of an intravascular rotary catheter for bimodal interrogation of arterial pathologies. This is based on a point-spectroscopy scanning time-resolved fluorescence spectroscopy technique enabling reconstruction of fluorescence lifetime images (FLIm) and providing information on arterial intima composition and intravascular ultrasound (IVUS) providing information on arterial wall morphology. The catheter design allows for independent rotation of the ultrasonic and optical channels within an 8 Fr outer diameter catheter sheath and integrates a low volume flushing channel for blood removal in the optical pathways. In the current configuration, the two channels consist of (a) a standard 3 Fr IVUS catheter with single element transducer (40 MHz) and (b) a side-viewing fiber optic (400 μm core). Experiments conducted in tissue phantoms showed the ability of the catheter to operate in an intraluminal setting and to generate coregistered FLIm and IVUS in one pull-back scan. Current results demonstrate the feasibility of the catheter for simultaneous bimodal interrogation of arterial lumen and for generation of robust fluorescence lifetime data under IVUS guidance. These results facilitate further development of a FLIm-IVUS technique for intravascular diagnosis of atherosclerotic cardiovascular diseases including vulnerable plaques. PMID:23224011

  1. Design, construction, and validation of a rotary multifunctional intravascular diagnostic catheter combining multispectral fluorescence lifetime imaging and intravascular ultrasound

    NASA Astrophysics Data System (ADS)

    Bec, Julien; Xie, Hongtao; Yankelevich, Diego R.; Zhou, Feifei; Sun, Yang; Ghata, Narugopal; Aldredge, Ralph; Marcu, Laura

    2012-10-01

    We report the development and validation of an intravascular rotary catheter for bimodal interrogation of arterial pathologies. This is based on a point-spectroscopy scanning time-resolved fluorescence spectroscopy technique enabling reconstruction of fluorescence lifetime images (FLIm) and providing information on arterial intima composition and intravascular ultrasound (IVUS) providing information on arterial wall morphology. The catheter design allows for independent rotation of the ultrasonic and optical channels within an 8 Fr outer diameter catheter sheath and integrates a low volume flushing channel for blood removal in the optical pathways. In the current configuration, the two channels consist of (a) a standard 3 Fr IVUS catheter with single element transducer (40 MHz) and (b) a side-viewing fiber optic (400 μm core). Experiments conducted in tissue phantoms showed the ability of the catheter to operate in an intraluminal setting and to generate coregistered FLIm and IVUS in one pull-back scan. Current results demonstrate the feasibility of the catheter for simultaneous bimodal interrogation of arterial lumen and for generation of robust fluorescence lifetime data under IVUS guidance. These results facilitate further development of a FLIm-IVUS technique for intravascular diagnosis of atherosclerotic cardiovascular diseases including vulnerable plaques.

  2. Clinical applications of high-intensity focused ultrasound.

    PubMed

    She, W H; Cheung, T T; Jenkins, C R; Irwin, M G

    2016-08-01

    Ultrasound has been developed for therapeutic use in addition to its diagnostic ability. The use of focused ultrasound energy can offer a non-invasive method for tissue ablation, and can therefore be used to treat various solid tumours. High-intensity focused ultrasound is being increasingly used in the treatment of both primary and metastatic tumours as these can be precisely located for ablation. It has been shown to be particularly useful in the treatment of uterine fibroids, and various solid tumours including those of the pancreas and liver. High-intensity focused ultrasound is a valid treatment option for liver tumours in patients with significant medical co-morbidity who are at high risk for surgery or who have relatively poor liver function that may preclude hepatectomy. It has also been used as a form of bridging therapy while patients awaiting cadaveric donor liver transplantation. In this article, we outline the principles of high-intensity focused ultrasound and its clinical applications, including the management protocol development in the treatment of hepatocellular carcinoma in Hong Kong by performing a search on MEDLINE (OVID), EMBASE, and PubMed. The search of these databases ranged from the date of their establishment until December 2015. The search terms used were: high-intensity focused ultrasound, ultrasound, magnetic resonance imaging, liver tumour, hepatocellular carcinoma, pancreas, renal cell carcinoma, prostate cancer, breast cancer, fibroids, bone tumour, atrial fibrillation, glaucoma, Parkinson's disease, essential tremor, and neuropathic pain. PMID:27380753

  3. Real-time implementation of the echo signal processing and digital scan conversion for medical ultrasound imaging with a single TMS320C6416 DSP

    NASA Astrophysics Data System (ADS)

    Lee, Choong; Sohn, Hak-Yeol; Han, Dong-Hoon; Song, Tai-Kyong

    2008-03-01

    Software implementation of a medical ultrasound imaging system using commercial DSPs (Digital Signal Processor) has advantages over FPGA- or ASIC-based system in development cost and time. The authors have developed a full software-based ultrasound scanner consisting of a typical analog front-end block and a DSP system. In this work, we present efficient methods for software realization of an echo processor to perform all the ultrasound signal processing functions following the receive beamforming. For implementation with a single TMS320C6416 DSP, the most computationally demanding functions such as dynamic filtering, quadrature demodulation, decimation, magnitude calculation, and log compression are implemented using modified algorithms and structures optimized to best match the DSP architecture for fast computation. The DSC (digital scan converter) is realized with an LUT for generating memory addresses and interpolation coefficients for each display point. The LUT table is stored in a single external SDRAM so that the internal DSP memory can be fully utilized by the DSP core to maximize the processing speed. The possible memory stall that can be caused by the external memory access is removed by properly employing the enhanced direct memory access channels. Experimental results show that the proposed implementation can support up to 4 kHz PRF (pulse repetition frequency) when the input data rate is 40 MHz.

  4. Medical Imaging Physics, 4th Edition

    NASA Astrophysics Data System (ADS)

    Hendee, William R.; Ritenour, E. Russell

    2002-05-01

    This comprehensive publication covers all aspects of image formation in modern medical imaging modalities, from radiography, fluoroscopy, and computed tomography, to magnetic resonance imaging and ultrasound. It addresses the techniques and instrumentation used in the rapidly changing field of medical imaging. Now in its fourth edition, this text provides the reader with the tools necessary to be comfortable with the physical principles, equipment, and procedures used in diagnostic imaging, as well as appreciate the capabilities and limitations of the technologies.

  5. Diagnostic performance of axial-strain sonoelastography in confirming clinically diagnosed Achilles tendinopathy: comparison with B-mode ultrasound and color Doppler imaging.

    PubMed

    Ooi, Chin Chin; Schneider, Michal Elisabeth; Malliaras, Peter; Chadwick, Martine; Connell, David Alister

    2015-01-01

    This primary aim of this study was to evaluate the diagnostic performance of axial-strain sonoelastography (ASE), B-mode ultrasound (US) and color Doppler US in confirming clinically symptomatic Achilles tendinopathy. The secondary aim was to establish the relationship between the strain ratio during sonoelastography and Victorian Institute of Sport Assessment-Achilles (VISA-A) scores. The VISA-A questionnaire is a validated clinical rating scale that evaluates the symptoms and dysfunction of the Achilles tendon. One hundred twenty Achilles tendons of 120 consecutively registered patients with clinical symptoms of Achilles tendinopathy and another 120 gender- and age-matched, asymptomatic Achilles tendons of 120 healthy volunteers were assessed with B-mode US, ASE and color Doppler US. Symptomatic patients had significantly higher strain ratio scores and softer Achilles tendon properties compared with controls (p < 0.001). The strain ratio was moderately correlated with VISA-A scores (r = -0.62, p < 0.001). The diagnostic accuracy of B-mode US, ASE and color Doppler US in confirming clinically symptomatic Achilles tendinopathy was 94.7%, 97.8% and 82.5% respectively. There was excellent correlation between the clinical reference standard and the grade of tendon quality on ASE (κ = 0.91, p < 0.05), compared with B-mode US (κ = 0.74, p < 0.05) and color Doppler imaging (κ = 0.49, p < 0.05). ASE is an accurate clinical tool in the evaluation of Achilles tendinopathy, with results comparable to those of B-mode US and excellent correlation with clinical findings. The strain ratio may offer promise as a supplementary tool for the objective evaluation of Achilles tendon properties. PMID:25438847

  6. Learning tumor diagnostics and medical image processing via the WWW--the case-based radiological textbook ODITEB.

    PubMed

    Horsch, A; Balbach, T; Melnitzki, S; Knauth, J

    2000-09-01

    New Internet technologies offer excellent chances to build high-quality on-line learning media for the education in medicine. Especially, the teaching of diagnostics with medical imaging as well as medical image processing can be supported by the excellent visualization and interaction capabilities. In cooperation with three radiological departments at German universities in Munich, Erlangen and Würzburg, the case-based open distributed Internet text book (ODITEB) for tumor diagnosis of the GI-tract, liver, pancreas and thorax has been developed at the Institut für Medizinische Statistik und Epidemiologie (IMSE) of the Technische Universität München. It offers a big collection of clinical tumor cases located on servers at the provider sites Munich, Erlangen and Würzburg, visualization and interaction similar to a real CT or MRI console, original DICOM data, X-rays and endoscopic and endosonographic videos, and expert-guided tours through the cases. In a first evaluation in summer 1998, 32 medical students graded the application with 1.9 ('good') on a scale from 1 ('very good') to 5 ('very bad'). The textbook supports German language, an English version is in preparation. In a second part, it contains lessons in medical image processing for students of medical informatics. An ODITEB release 2 with several improvements will be finished until February 2000. The use of the textbook is free of cost. PMID:10978908

  7. TH-E-9A-01: Medical Physics 1.0 to 2.0, Session 4: Computed Tomography, Ultrasound and Nuclear Medicine

    SciTech Connect

    Samei, E; Nelson, J; Hangiandreou, N

    2014-06-15

    communication, use optimization (dose and technique factors), automated analysis and data management (automated QC methods, protocol tracking, dose monitoring, issue tracking), and meaningful QC considerations. US 2.0: Ultrasound imaging is evolving at a rapid pace, adding new imaging functions and modes that continue to enhance its clinical utility and benefits to patients. The ultrasound talk will look ahead 10–15 years and consider how medical physicists can bring maximal value to the clinical ultrasound practices of the future. The roles of physics in accreditation and regulatory compliance, image quality and exam optimization, clinical innovation, and education of staff and trainees will all be considered. A detailed examination of expected technology evolution and impact on image quality metrics will be presented. Clinical implementation of comprehensive physics services will also be discussed. Nuclear Medicine 2.0: Although the basic science of nuclear imaging has remained relatively unchanged since its inception, advances in instrumentation continue to advance the field into new territories. With a great number of these advances occurring over the past decade, the role and testing strategies of clinical nuclear medicine physicists must evolve in parallel. The Nuclear Medicine 2.0 presentation is designed to highlight some of the recent advances from a clinical medical physicist perspective and provide ideas and motivation for designing better evaluation strategies. Topics include improvement of traditional physics metrics and analytics, testing implications of hybrid imaging and advanced detector technologies, and strategies for effective implementation into the clinic. Learning Objectives: Become familiar with new physics metrics and analytics in nuclear medicine, CT, and ultrasound. To become familiar with the major new developments of clinical physics support. To understand the physics testing implications of new technologies, hardware, software, and applications

  8. Effect of the angular aperture of medical ultrasound transducers on the parameters of nonlinear ultrasound field with shocks at the focus

    NASA Astrophysics Data System (ADS)

    Rosnitskiy, P. B.; Yuldashev, P. V.; Khokhlova, V. A.

    2015-05-01

    Certain modern applications of high-intensity focused ultrasound (HIFU) in medicine use the nonlinear effect of shock front formation in the focal waveform. However, an important problem remains unsolved: determination of transducer parameters that provide the given pressure levels of the shock wave field at the focus required for a specific application. In this paper, simulations based on the Khokhlov-Zabolotskaya equation are performed to test and confirm the hypothesis that angular aperture of the transducer is the main parameter that determines the characteristic amplitude of the shock front and corresponding values for the peak positive and negative pressures at the focus. A criterion for formation of a developed shock in the acoustic waveform, as well as a method for determining its amplitude is proposed. Quantitative dependences of the amplitude of the developed shock and the peak pressures in the wave profile on the angular aperture of the transducer are calculated. The effects of saturation and the range of changes of the shock waveform parameters at the focus are analyzed for a typical HIFU transducer.

  9. Ultrasound in perinatology

    SciTech Connect

    Maklad, N.F.

    1986-01-01

    This 19th volume in the series Clinics in Diagnostic Ultrasound provides an overview and update of some of the recent applications of ultrasound (US) in the pernatal period. Prenatal topics include estimation of gestational age; evaluation of intrauterine growth retardation, non-immune hydrops, and fetal urinary abnormalities; fetal echocardiography; and biophysical scoring. The discussion of postnatal topics includes US studies of the head and abdomen, echocardiography, and interventional procedures.

  10. Ultrasound simulation in bone.

    PubMed

    Kaufman, Jonathan J; Luo, Gangming; Siffert, Robert S

    2008-01-01

    The manner in which ultrasound interacts with bone is of key interest in therapy and diagnosis alike. These may include applications directly to bone, as, for example, in treatment to accelerate the healing of bone fractures and in assessment of bone density in osteoporosis, or indirectly in diagnostic imaging of soft tissue with interest in assessing exposure levels to nearby bone. Because of the lack of analytic solutions to virtually every "practical problem" encountered clinically, ultrasound simulation has become a widely used technique for evaluating ultrasound interactions in bone. This paper provides an overview of the use of ultrasound simulation in bone. A brief description of the mathematical model used to characterize ultrasound propagation in bone is first provided. A number of simulation examples are then presented that explain how simulation may be utilized in a variety of practical configurations. The focus of this paper in terms of examples presented is on diagnostic applications in bone, and, in particular, for assessment of osteoporosis. However, the use of simulation in other areas of interest can easily be extrapolated from the examples presented. In conclusion, this paper describes the use of ultrasound simulation in bone and demonstrates the power of computational methods for ultrasound research in general and tissue and bone applications in particular. PMID:18599409

  11. Integrating Nursing Diagnostic Concepts into the Medical Entities Dictionary Using the ISO Reference Terminology Model for Nursing Diagnosis

    PubMed Central

    Hwang, Jee-In; Cimino, James J.; Bakken, Suzanne

    2003-01-01

    Objective: The purposes of the study were (1) to evaluate the usefulness of the International Standards Organization (ISO) Reference Terminology Model for Nursing Diagnoses as a terminology model for defining nursing diagnostic concepts in the Medical Entities Dictionary (MED) and (2) to create the additional hierarchical structures required for integration of nursing diagnostic concepts into the MED. Design and Measurements: The authors dissected nursing diagnostic terms from two source terminologies (Home Health Care Classification and the Omaha System) into the semantic categories of the ISO model. Consistent with the ISO model, they selected Focus and Judgment as required semantic categories for creating intensional definitions of nursing diagnostic concepts in the MED. Because the MED does not include Focus and Judgment hierarchies, the authors developed them to define the nursing diagnostic concepts. Results: The ISO model was sufficient for dissecting the source terminologies into atomic terms. The authors identified 162 unique focus concepts from the 266 nursing diagnosis terms for inclusion in the Focus hierarchy. For the Judgment hierarchy, the authors precoordinated Judgment and Potentiality instead of using Potentiality as a qualifier of Judgment as in the ISO model. Impairment and Alteration were the most frequently occurring judgments. Conclusions: Nursing care represents a large proportion of health care activities; thus, it is vital that terms used by nurses are integrated into concept-oriented terminologies that provide broad coverage for the domain of health care. This study supports the utility of the ISO Reference Terminology Model for Nursing Diagnoses as a facilitator for the integration process. PMID:12668692

  12. Can Doppler or contrast-enhanced ultrasound analysis add diagnostically important information about the nature of breast lesions?

    PubMed Central

    Stanzani, Daniela; Chala, Luciano F.; de Barros, Nestor; Cerri, Giovanni G.; Chammas, Maria Cristina

    2014-01-01

    OBJECTIVES: Despite evidence suggesting that Doppler ultrasonography can help to differentiate between benign and malignant breast lesions, it is rarely applied in clinical practice. The aim of this study was to determine whether certain vascular features of breast masses observed by duplex Doppler and color Doppler ultrasonography (before and/or after microbubble contrast injection) add information to the gray-scale analysis and support the Breast Imaging-Reporting and Data System (BI-RADS) classification. METHODS: Seventy solid lesions were prospectively evaluated with gray-scale ultrasonography, color Doppler ultrasonography, and contrast-enhanced ultrasonography. The morphological analysis and lesion vascularity were correlated with the histological results. RESULTS: Percutaneous core biopsies revealed that 25/70 (17.5%) lesions were malignant, while 45 were benign. Hypervascular lesions with tortuous and central vessels, a resistive index (RI)≥0.73 before contrast injection, and an RI≥0.75 after contrast injection were significantly predictive of malignancy (p<0.001). CONCLUSION: The combination of gray-scale ultrasonography data with unenhanced or enhanced duplex Doppler and color Doppler US data can provide diagnostically useful information. These techniques can be easily implemented because Doppler devices are already present in most health centers. PMID:24519198

  13. Exploring medical diagnostic performance using interactive, multi-parameter sourced receiver operating characteristic scatter plots.

    PubMed

    Moore, Hyatt E; Andlauer, Olivier; Simon, Noah; Mignot, Emmanuel

    2014-04-01

    Determining diagnostic criteria for specific disorders is often a tedious task that involves determining optimal diagnostic thresholds for symptoms and biomarkers using receiver-operating characteristic (ROC) statistics. To help this endeavor, we developed softROC, a user-friendly graphic-based tool that lets users visually explore possible ROC tradeoffs. The software requires MATLAB installation and an Excel file containing threshold symptoms/biological measures, with corresponding gold standard diagnoses for a set of patients. The software scans the input file for diagnostic and symptom/biomarkers columns, and populates the graphical-user-interface (GUI). Users select symptoms/biomarkers of interest using Boolean algebra as potential inputs to create diagnostic criteria outputs. The software evaluates subtests across the user-established range of cut-points and compares them to a gold standard in order to generate ROC and quality ROC scatter plots. These plots can be examined interactively to find optimal cut-points of interest for a given application (e.g. sensitivity versus specificity needs). Split-set validation can also be used to set up criteria and validate these in independent samples. Bootstrapping is used to produce confidence intervals. Additional statistics and measures are provided, such as the area under the ROC curve (AUC). As a testing set, softROC is used to investigate nocturnal polysomnogram measures as diagnostic features for narcolepsy. All measures can be outputted to a text file for offline analysis. The softROC toolbox, with clinical training data and tutorial instruction manual, is provided as supplementary material and can be obtained online at http://www.stanford.edu/~hyatt4/software/softroc or from the open source repository at http://www.github.com/informaton/softroc. PMID:24561350

  14. Prostate Ultrasound

    MedlinePlus

    ... waves. Ultrasound imaging, also called ultrasound scanning or sonography , involves the use of a small transducer (probe) and ultrasound gel placed directly on the skin. High-frequency sound waves are transmitted from the ...

  15. Hip Ultrasound

    MedlinePlus

    ... waves. Ultrasound imaging, also called ultrasound scanning or sonography , involves the use of a small transducer (probe) and ultrasound gel placed directly on the skin. High-frequency sound waves are transmitted from the ...

  16. Ultrasound -- Vascular

    MedlinePlus

    ... waves. Ultrasound imaging, also called ultrasound scanning or sonography , involves the use of a small transducer (probe) and ultrasound gel placed directly on the skin. High-frequency sound waves are transmitted from the ...

  17. Musculoskeletal Ultrasound

    MedlinePlus

    ... waves. Ultrasound imaging, also called ultrasound scanning or sonography , involves the use of a small transducer (probe) and ultrasound gel placed directly on the skin. High-frequency sound waves are transmitted from the ...

  18. Ultrasound - Scrotum

    MedlinePlus

    ... waves. Ultrasound imaging, also called ultrasound scanning or sonography , involves the use of a small transducer (probe) and ultrasound gel placed directly on the skin. High-frequency sound waves are transmitted from the ...

  19. The Adult Patient with Eisenmenger Syndrome: A Medical Update After Dana Point Part I: Epidemiology, Clinical Aspects and Diagnostic Options

    PubMed Central

    Kaemmerer, Harald; Mebus, Siegrun; Schulze-Neick, Ingram; Eicken, Andreas; Trindade, Pedro T; Hager, Alfred; Oechslin, Erwin; Niwa, Koichiro; Lang, Irene; Hess, John

    2010-01-01

    Eisenmenger syndrome is the most severe form of pulmonary arterial hypertension and arises on the basis of congenital heart disease with a systemic-to-pulmonary shunt. Due to the chronic slow progressive hypoxemia with central cyanosis, adult patients with the Eisenmenger syndrome suffer from a complex and multisystemic disorder including coagulation disorders (bleeding complications and paradoxical embolisms), renal dysfunction, hypertrophic osteoarthropathy, heart failure, reduced quality of life and premature death. For a long time, therapy has been limited to symptomatic options or lung or combined heart-lung transplantation. As new selective pulmonary vasodilators have become available and proven to be beneficial in various forms of pulmonary arterial hypertension, this targeted medical treatment has been expected to show promising effects with a delay of deterioration also in Eisenmenger patients. Unfortunately, data in Eisenmenger patients suffer from small patient numbers and a lack of randomized controlled studies. To optimize the quality of life and the outcome, referral of Eisenmenger patients to spezialized centers is required. In such centers, specific interdisciplinary management strategies of physicians specialized on congenital heart diseases and PAH should be warranted. This medical update emphasizes the current diagnostic and therapeutic options for Eisenmenger patients with particularly focussing on epidemiology, clinical aspects and specific diagnostic options. PMID:22043211

  20. Performance analysis of medical video streaming over mobile WiMAX.

    PubMed

    Alinejad, Ali; Philip, N; Istepanian, R H

    2010-01-01

    Wireless medical ultrasound streaming is considered one of the emerging application within the broadband mobile healthcare domain. These applications are considered as bandwidth demanding services that required high data rates with acceptable diagnostic quality of the transmitted medical images. In this paper, we present the performance analysis of a medical ultrasound video streaming acquired via special robotic ultrasonography system over emulated WiMAX wireless network. The experimental set-up of this application is described together with the performance of the relevant medical quality of service (m-QoS) metrics. PMID:21097263

  1. [Delayed appendectomy because of diagnostic malpractice: Experiences of the Arbitration Board of the North German Medical Associations].

    PubMed

    Vinz, Heinrich; von Bülow, Markward; Neu, Johann

    2015-01-01

    From 2000 to 2012, 447 panel proceedings concerning acute appendicitis were evaluated. 271 cases (57 %) were related to alleged diagnostic malpractice. This was confirmed in 176 cases (67 %). The following medical specialities were involved (m = quote of malpractice): general surgery 33 %, m = 51 %; paediatric surgery 3 %, m = 44 %; general practitioner and prehospital emergency services 24 %, m = 62 %; internal medicine 19 %, m = 70 %; paediatrics 13 %, m = 57 %; gynaecology 3 %, m = 91 %; urology 2 %, m = 17 %. The most frequent misdiagnosis was gastroenteritis (43 % in adults, 69 % in children), obviously based on the concomitant symptom of diarrhoea. Surgery revealed all stages of advanced appendicitis up to peritoneal sepsis, organic failure and death (n = 5). The evaluation of the files and the experts' reports of the 176 cases of diagnostic malpractice allowed to define the following basic failures, which led to unjustified delay of operation: careless history-taking, no or incomplete physical examination, no follow-up investigations, incorrect interpretation of the patient's complaints and clinical findings, no or incomplete documentation. Conducting a thorough investigation is essential to avoiding diagnostic malpractice. Internal analysis of failures or near failures may contribute to reducing the number of future cases of malpractice. PMID:26699259

  2. Raman spectroscopy for medical diagnostics--From in-vitro biofluid assays to in-vivo cancer detection.

    PubMed

    Kong, Kenny; Kendall, Catherine; Stone, Nicholas; Notingher, Ioan

    2015-07-15

    Raman spectroscopy is an optical technique based on inelastic scattering of light by vibrating molecules and can provide chemical fingerprints of cells, tissues or biofluids. The high chemical specificity, minimal or lack of sample preparation and the ability to use advanced optical technologies in the visible or near-infrared spectral range (lasers, microscopes, fibre-optics) have recently led to an increase in medical diagnostic applications of Raman spectroscopy. The key hypothesis underpinning this field is that molecular changes in cells, tissues or biofluids, that are either the cause or the effect of diseases, can be detected and quantified by Raman spectroscopy. Furthermore, multivariate calibration and classification models based on Raman spectra can be developed on large "training" datasets and used subsequently on samples from new patients to obtain quantitative and objective diagnosis. Historically, spontaneous Raman spectroscopy has been known as a low signal technique requiring relatively long acquisition times. Nevertheless, new strategies have been developed recently to overcome these issues: non-linear optical effects and metallic nanoparticles can be used to enhance the Raman signals, optimised fibre-optic Raman probes can be used for real-time in-vivo single-point measurements, while multimodal integration with other optical techniques can guide the Raman measurements to increase the acquisition speed and spatial accuracy of diagnosis. These recent efforts have advanced Raman spectroscopy to the point where the diagnostic accuracy and speed are compatible with clinical use. This paper reviews the main Raman spectroscopy techniques used in medical diagnostics and provides an overview of various applications. PMID:25809988

  3. Are natural products and medical diagnostic tests still eligible for patents in the USA?

    PubMed

    Cockbain, Julian; Sterckx, Sigrid

    2012-09-01

    In 2010, the biotechnology and molecular diagnostics industries were shocked by the decision from a US District Court to the effect that isolated endogenous DNA and diagnostic tests based on newly discovered DNA sequences were not eligible for US patents. The case related to the BRCA1/2 genes for breast and ovarian cancer. On appeal, the decision was almost entirely overturned. However, in March 2012, the US Supreme Court vacated the appeal court decision and instructed the appeals court to rehear the case in the light of its very recent decision, which suggested that products of nature and their obvious uses should not be patentable. This commentary explores the points at issue. PMID:24236874

  4. The Value of Ultrasound and Magnetic Resonance Imaging in Diagnostics and Prediction of Morbidity in Cases of Placenta Previa with Abnormal Placentation

    PubMed Central

    Algebally, Ahmed M.; Yousef, Reda Ramadan Hussein; Badr, Sanaa Sayed Hussein; Al Obeidly, Amal; Szmigielski, Wojciech; Al Ibrahim, Abdullah A.

    2014-01-01

    Summary Background The purpose of the study was to evaluate the role of ultrasound (US) and magnetic resonance imaging (MRI) in the diagnostics and management of abnormal placentation in women with placenta previa and to compare the morbidity associated with that to placenta previa alone. Material/Methods The study includes 100 pregnant women with placenta previa with and without abnormal placentation. The results of MRI and US in abnormal placentation were compared with post-operative data. The patients’ files were reviewed for assessment of operative and post-operative morbidity. The results of our statistical analysis were compared with data from the literature. Results US and MRI showed no significant difference in sensitivity and specificity in diagnosing abnormal placentation (97–100% and 94–100%, respectively). MRI was more sensitive than US for the detection of myometrial invasion and the type of abnormal placentation (73.5% and 47%, respectively). The difference between pre- and post-operative hemoglobin values and estimated blood loss were the most significant risk factors for abnormal placentation, added to risk factors known for placenta previa. Post-partum surgical complications and prolonged hospital stay were more common in the cases of placenta previa with abnormal placentation, however statistically insignificant. Conclusions US and MRI are accurate imaging modalities for diagnosing abnormal placentation. MRI was more sensitive for the detection of the degree of placental invasion. The patient’s morbidity increased in cases with abnormal placentation. There was no significant difference in post operative-complications and hospitalization time due to pre-operative planning when the diagnosis was established with US and MRI. PMID:25411586

  5. Assessment of portal contribution to liver perfusion by quantitative sequential scintigraphy and Doppler ultrasound in alcoholic cirrhosis. Diagnostic value in the detection of portal hypertension.

    PubMed

    Dao, T; Elfadel, S; Bouvard, G; Bouvard, N; Lecointe, I; Jardin-Grimaux, I; Verwaerde, J C; Valla, A

    1993-03-01

    To assess the portal contribution to liver perfusion, we carried out quantitative sequential scintigraphy in 110 patients with alcoholic cirrhosis (22 Child-Pugh class A, 39 class B, 49 class C) and 15 normal subjects. Duplex Doppler ultrasound found a type of intrahepatic circulation that made the standard scintigraphic procedure inaccurate in four cases of cirrhosis, which were reevaluated. Portal contribution to liver perfusion was lower in cirrhotics than in normal subjects (48.7 +/- 29% versus 78.4 +/- 6%; p < 0.001). The sensitivity of scintigraphy in detecting portal hypertension, based on portal contribution < or = 66%, was 61.8% (with a 100% specificity) compared with 66.7% for endoscopy (diagnosis based on existence of varices). The overall sensitivity of the two tests together was 86.1%. Portal contribution to liver perfusion was inversely correlated to Child-Pugh score (r = 0.53; p < 0.001), to prothrombin time (r = 0.52; p < 0.001), and to hepatic venous pressure gradient (r = 0.43; p < 0.001) and positively correlated to albuminemia (r = 0.42; p < 0.001). Concurrent alcoholic hepatitis and the existence of large portosystemic collaterals were related to a decrease in portal contribution to liver perfusion. We conclude that quantitative sequential scintigraphy, which shows a direct relationship between portal contribution to liver perfusion, on the one hand, and the amount of portosystemic shunting, the progression of liver disease, and/or acute liver injury, on the other, could serve as a diagnostic test for portal hypertension. The addition of scintigraphy improves the overall sensitivity of endoscopy. PMID:8463621

  6. Design of decision support system when undertaking medical-diagnostic action

    NASA Astrophysics Data System (ADS)

    Povoroznyuk, Anatoliy I.; Filatova, Anna E.; Surtel, Wojciech; Burlibay, Aron; Zhassandykyzy, Maral

    2015-12-01

    In the work the formalization of the problem of diagnostic and treatment activities (DTA) steps complex estimation for increasing of their efficiency and minimization of the risk of doctor's mistakes was completed. The decision support system during conducting of DTA based on formalizations of steps of DTA performing with theirs complex estimation was developed that allows to minimize the risks of doctor's mistakes, raise validity of decisions.

  7. Integration of a bioMEMS device into a disposable microfluidic cartridge for medical diagnostics

    NASA Astrophysics Data System (ADS)

    Ortiz, Pedro; Keegan, Neil; Spoors, Julia; Hedley, John; Harris, Alun; Burdess, Jim; Burnett, Richard; Velten, Thomas; Biehl, Margit; Knoll, Thorsten; Haberer, Werner; Solomon, Matthew; Campitelli, Andrew; McNeil, Calum

    2009-02-01

    A microfluidic system for cancer diagnostics based around a core MEMS biosensor technology is presented in this paper. The principle of the MEMS biosensor is introduced and the functionalisation strategy for cancer marker recognition is described. In addition, the successful packaging and integration of functional MEMS biosensor devices are reported herein. This ongoing work represents one of the first hybrid systems to integrate a PCB packaged silicon MEMS device into a disposable microfluidic cartridge.

  8. Contrast-enhanced and targeted ultrasound

    PubMed Central

    Postema, Michiel; Gilja, Odd Helge

    2011-01-01

    Ultrasonic imaging is becoming the most popular medical imaging modality, owing to the low price per examination and its safety. However, blood is a poor scatterer of ultrasound waves at clinical diagnostic transmit frequencies. For perfusion imaging, markers have been designed to enhance the contrast in B-mode imaging. These so-called ultrasound contrast agents consist of microscopically small gas bubbles encapsulated in biodegradable shells. In this review, the physical principles of ultrasound contrast agent microbubble behavior and their adjustment for drug delivery including sonoporation are described. Furthermore, an outline of clinical imaging applications of contrast-enhanced ultrasound is given. It is a challenging task to quantify and predict which bubble phenomenon occurs under which acoustic condition, and how these phenomena may be utilized in ultrasonic imaging. Aided by high-speed photography, our improved understanding of encapsulated microbubble behavior will lead to more sophisticated detection and delivery techniques. More sophisticated methods use quantitative approaches to measure the amount and the time course of bolus or reperfusion curves, and have shown great promise in revealing effective tumor responses to anti-angiogenic drugs in humans before tumor shrinkage occurs. These are beginning to be accepted into clinical practice. In the long term, targeted microbubbles for molecular imaging and eventually for directed anti-tumor therapy are expected to be tested. PMID:21218081

  9. Contrast-enhanced and targeted ultrasound.

    PubMed

    Postema, Michiel; Gilja, Odd Helge

    2011-01-01

    Ultrasonic imaging is becoming the most popular medical imaging modality, owing to the low price per examination and its safety. However, blood is a poor scatterer of ultrasound waves at clinical diagnostic transmit frequencies. For perfusion imaging, markers have been designed to enhance the contrast in B-mode imaging. These so-called ultrasound contrast agents consist of microscopically small gas bubbles encapsulated in biodegradable shells. In this review, the physical principles of ultrasound contrast agent microbubble behavior and their adjustment for drug delivery including sonoporation are described. Furthermore, an outline of clinical imaging applications of contrast-enhanced ultrasound is given. It is a challenging task to quantify and predict which bubble phenomenon occurs under which acoustic condition, and how these phenomena may be utilized in ultrasonic imaging. Aided by high-speed photography, our improved understanding of encapsulated microbubble behavior will lead to more sophisticated detection and delivery techniques. More sophisticated methods use quantitative approaches to measure the amount and the time course of bolus or reperfusion curves, and have shown great promise in revealing effective tumor responses to anti-angiogenic drugs in humans before tumor shrinkage occurs. These are beginning to be accepted into clinical practice. In the long term, targeted microbubbles for molecular imaging and eventually for directed anti-tumor therapy are expected to be tested. PMID:21218081

  10. Medical Diagnostic Consultation concerning Mental Retardation: An Analogue Study of School Psychologists' Attitudes

    ERIC Educational Resources Information Center

    Wodrich, David L.; Tarbox, Jennifer; Balles, John; Gorin, Joanna

    2010-01-01

    Recent research of relevance to school psychologists suggests that the cause, or etiology, of mental retardation can be established by medical diagnosticians in approximately one-half of cases. In the current study, 109 practicing school psychologists considered a hypothetical case of an elementary student with mental retardation and indicated…

  11. The Ambulatory Diagnostic and Treatment Center: A Unique Model for Educating Medical Trainees and Providing Expedited Care.

    PubMed

    Serrao, Richard A; Orlander, Jay D

    2016-05-01

    In this article, the authors reexamine the Ambulatory Diagnostic and Treatment Center (ADTC) model, which uniquely combines the education of trainees with the care of referred patients at one Veterans Affairs medical center. As an ambulatory clinic with an inpatient mind-set, the ADTC uses a series of closely spaced outpatient appointments that are longer than typical ambulatory visits, offering a VIP-level of evaluation with the patient-centered goal of expedited diagnosis and treatment. Faculty triage patients by weighing factors such as urgency, educational value, complexity, and instability of diseases in conjunction with the resources, availability, and appropriateness of other services within the medical center.The ADTC's unique focus on the education of trainees in comparison with other clinical rotations is evident in the ratio of learning to patient care. This intensive training environment expects postgraduate year 2 and 3 internal medicine residents and fourth-year medical students to read, reflect, and review literature daily. This mix of education and care delivery is ripe for reexploration in light of recent calls for curriculum reform amidst headlines exposing delays in veterans' access to care.A low-volume, high-intensity clinic like the ADTC can augment the clinical services provided by a busy primary care and subspecialty workforce without losing its emphasis on education. Other academic health centers can learn from this model and adapt its structure in settings where accountable care organizations and education meet. PMID:26839944

  12. The benomyl test as a fundamental diagnostic method for medical mycology.

    PubMed Central

    Summerbell, R C

    1993-01-01

    The fungicide benomyl has long been known to differentially affect major taxonomic groups of fungi. In the present study 163 species or aggregates of closely similar species of medically important fungi and actinomycetes, as well as species commonly isolated as clinical contaminants, were tested to determine their reactions to three concentrations of benomyl. Fungi of basidiomycetous, endomycetous, and microascaceous affinities were highly resistant, including all common yeasts and Geotrichum, Pseudallescheria, Scedosporium, and Scopulariopsis species. Also resistant were fungi of pleosporalean affinities with poroconidial anamorphs, such as Alternaria, Bipolaris, Curvularia, and Exserohilum species. Most other fungi of ascomycetous affinity were moderately to strongly susceptible. Such fungi included dermatophytes; Coccidioides, Blastomyces, and Histoplasma species; Sporothrix schenckii; medically important aspergilli; and "black yeasts." Benomyl testing aided in the provisional identification of nonsporulating mycelia, including common basidiomycetous isolates obtained as contaminants as well as nonsporulating Aspergillus fumigatus from pulmonary sources. PMID:8458952

  13. A Diagnostic Analysis of Erroneous Language in Iranian Medical Specialists’ Research Papers

    PubMed Central

    Gholami, Javad; Zeinolabedini, Maryam

    2015-01-01

    Abstract Background: As English has increasingly become the lingua franca in science and international journals require native-like academic writing standards from nonnative researchers, there is more pressure on nonnative scholars to write their research articles more accurately and appropriately in English. This study was conducted to determine the most-occurring language-related errors which Iranian medical authors/researchers commit while trying to have their research published in international English journals. Also, this article seeks to provide useful guidelines to reduce such linguistic mistakes. Methods: The present study investigated the most common language-related errors in Iranian medical specialists’ research articles. To this end, the first drafts of 60 published research articles in medical sciences were cross-checked against their peer-reviewed published versions in order to identify the most frequent non-target language forms which received discoursal, lexical, grammatical, and mechanical revisions by peer editors. Results: The findings revealed that the editors had surprisingly dealt with discoursal errors more than any other linguistic aspects of these research articles. This was followed by lexical replacements. In third place were grammatical improvements, where erroneous structures mostly related to tenses, usage of articles and prepositions, and agreement between verbs and nouns were treated. The least common revisions were on the mechanics of academic writing, consisting of hyphenating, spelling, case lettering, spacing, and spacing with commas. Conclusion: Although most of the Iranian medical authors/researchers enjoyed a good level of proficiency in English, their manuscripts required discoursal, lexical, grammatical, and mechanical revisions before publication in credited international journals. PMID:26157466

  14. Advanced diagnostic approaches and current medical management of insulinomas and adrenocortical disease in ferrets (Mustela putorius furo).

    PubMed

    Chen, Sue

    2010-09-01

    Endocrine neoplasia is the most common tumor type in domestic ferrets, especially in middle-aged to older ferrets. Islet cell tumors and adrenocortical tumors constitute the major types of endocrine neoplasms. Insulinoma is a tumor that produces and releases excessive amounts of insulin. Evaluation of fasted blood glucose levels provides a quick diagnostic assessment for the detection of insulinomas. Use of glucocorticoids, diazoxide, and diet modification are some of the medical treatment options for insulinomas. Adrenocortical neoplasia in ferrets usually overproduces one or more sex hormones. Sex hormones which can result in progressive alopecia, vulvar swelling in females, and prostagomegaly in males. Abdominal ultrasonography and sex hormone assays can be used to diagnose adrenocortical neoplasms. Drugs such as leuprolide acetate, deslorelin acetate, and the hormone melatonin can be used to treat adrenocortical neoplasms in ferrets when surgery is not an option. PMID:20682429

  15. Microfluidic blood plasma separation for medical diagnostics: is it worth it?

    PubMed

    Mielczarek, W S; Obaje, E A; Bachmann, T T; Kersaudy-Kerhoas, M

    2016-09-21

    Circulating biomarkers are on the verge of becoming powerful diagnostic tools for various human diseases. However, the complex sample composition makes it difficult to detect biomarkers directly from blood at the bench or at the point-of-care. Blood cells are often a source of variability of the biomarker signal. While the interference of hemoglobin is a long known source of variability, the release of nucleic acids and other cellular components from hemocytes is a new concern for measurement and detection of circulating extracellular markers. Research into miniaturised blood plasma separation has been thriving in the last 10 years (2006-2016). Most point-of-care systems need microscale blood plasma separation, but developed solutions differ in complexity and sample volume range. But could blood plasma separation be avoided completely? This focused review weights the advantages and limits of miniaturised blood plasma separation and highlights the most interesting advances in direct capture as well as smart blood plasma separation. PMID:27502438

  16. Ultrasound and the IRB

    ERIC Educational Resources Information Center

    Epstein, Melissa A.

    2005-01-01

    The purpose of this paper is to assist researchers in writing their research protocols and subject consent forms so that both the Institutional Review Board (IRB) and subjects are assured of the minimal risk associated with diagnostic B-scan ultrasound as it is used in speech research. There have been numerous epidemiological studies on fetal…

  17. Performance of Physical Examination Skills in Medical Students during Diagnostic Medicine Course in a University Hospital of Northwest China

    PubMed Central

    Li, Yan; Li, Na; Han, Qunying; He, Shuixiang; Bae, Ricard S.; Liu, Zhengwen; Lv, Yi; Shi, Bingyin

    2014-01-01

    This study was conducted to evaluate the performance of physical examination (PE) skills during our diagnostic medicine course and analyze the characteristics of the data collected to provide information for practical guidance to improve the quality of teaching. Seventy-two fourth-year medical students were enrolled in the study. All received an assessment of PE skills after receiving a 17-week formal training course and systematic teaching. Their performance was evaluated and recorded in detail using a checklist, which included 5 aspects of PE skills: examination techniques, communication and care skills, content items, appropriateness of examination sequence, and time taken. Error frequency and type were designated as the assessment parameters in the survey. The results showed that the distribution and the percentage in examination errors between male and female students and among the different body parts examined were significantly different (p<0.001). The average error frequency per student in females (0.875) was lower than in males (1.375) although the difference was not statistically significant (p = 0.167). The average error frequency per student in cardiac (1.267) and pulmonary (1.389) examinations was higher than in abdominal (0.867) and head, neck and nervous system examinations (0.917). Female students had a lower average error frequency than males in cardiac examinations (p = 0.041). Additionally, error in examination techniques was the highest type of error among the 5 aspects of PE skills irrespective of participant gender and assessment content (p<0.001). These data suggest that PE skills in cardiac and pulmonary examinations and examination techniques may be included in the main focus of improving the teaching of diagnostics in these medical students. PMID:25329685

  18. Diagnostic Analysis Of Ultrasound Data

    DOEpatents

    Chambers, David H.; Mast, Jeffrey; Azevedo, Stephen G.; Wuebbeling, Frank; Natterer, Frank; Duric, Neb; Littrup, Peter J.; Holsapple, Earle

    2006-01-10

    A method and apparatus are provided for investigating tissue in which acoustic data are derived from scattering a plurality of pulsed spherical or cylindrical acoustic waves from a plurality of transmission elements through the tissue to a plurality of receiving elements. The acoustic data, which include a mix of reflected and transmitted acoustic waves, are received and digitized, and a representation of a portion of the tissue is generated from the digitized acoustic data.

  19. Delay, change and bifurcation of the immunofluorescence distribution attractors in health statuses diagnostics and in medical treatment

    NASA Astrophysics Data System (ADS)

    Galich, Nikolay E.; Filatov, Michael V.

    2008-07-01

    Communication contains the description of the immunology experiments and the experimental data treatment. New nonlinear methods of immunofluorescence statistical analysis of peripheral blood neutrophils have been developed. We used technology of respiratory burst reaction of DNA fluorescence in the neutrophils cells nuclei due to oxidative activity. The histograms of photon count statistics the radiant neutrophils populations' in flow cytometry experiments are considered. Distributions of the fluorescence flashes frequency as functions of the fluorescence intensity are analyzed. Statistic peculiarities of histograms set for healthy and unhealthy donors allow dividing all histograms on the three classes. The classification is based on three different types of smoothing and long-range scale averaged immunofluorescence distributions and their bifurcation. Heterogeneity peculiarities of long-range scale immunofluorescence distributions allow dividing all histograms on three groups. First histograms group belongs to healthy donors. Two other groups belong to donors with autoimmune and inflammatory diseases. Some of the illnesses are not diagnosed by standards biochemical methods. Medical standards and statistical data of the immunofluorescence histograms for identifications of health and illnesses are interconnected. Possibilities and alterations of immunofluorescence statistics in registration, diagnostics and monitoring of different diseases in various medical treatments have been demonstrated. Health or illness criteria are connected with statistics features of immunofluorescence histograms. Neutrophils populations' fluorescence presents the sensitive clear indicator of health status.

  20. Verification of in vitro medical diagnostics (IVD) metrological traceability: responsibilities and strategies.

    PubMed

    Braga, Federica; Panteghini, Mauro

    2014-05-15

    To be accurate and equivalent, laboratory results should be traceable to higher-order references. Furthermore, their analytical performance should fulfill acceptable measurement uncertainty criteria defined to fit the intended clinical use. With this aim, In Vitro Diagnostics (IVD) manufacturers should define a calibration hierarchy to assign traceable values to their system calibrators and to fulfill during this process uncertainty limits for calibrators, which should represent a proportion of the uncertainty budget allowed for laboratory results. It is important that end-users may know and verify how manufacturers have implemented the traceability of their calibrators and estimated the corresponding uncertainty. However, full information about traceability and combined uncertainty of calibrators is currently not available. Important tools for IVD traceability surveillance are the verification by laboratories of the consistency of declared performance during daily operations performed in accordance with the manufacturer's instructions and the organization of appropriately structured External Quality Assessment (EQA) programs. The former activity should be accomplished by analyzing system control materials and confirming that current measurements are in the manufacturer's established control range. With regard to EQA, it is mandatory that target values for materials are assigned with reference procedures by accredited laboratories, that materials are commutable and that a clinically allowable inaccuracy for participant's results is defined. PMID:24291059

  1. [Forensic medical diagnostics of intoxication with certain poisonous mushrooms in the case of the lethal outcome in a hospital].

    PubMed

    Zaraf'aynts, G N

    2016-01-01

    The present study was undertaken with a view to improving forensic medical diagnostics of intoxication with poisonous mushrooms in the cases of patients' death in a hospital. A total of 15 protocols of forensic medical examination of the corpses of the people who had died from acute poisoning were available for the analysis. The deathly toxins were amanitin and muscarine contained in various combinations in the death cap (Amanita phalloides) and the early false morels (Gyromitra esculenta and G. gigas). The main poisoning season in the former case was May and in the latter case August and September (93.4%). The mortality rate in the case of group intoxication (such cases accounted for 40% of the total) amounted to 28.6%. 40% of the deceased subjects consumed mushrooms together with alcohol. The poisoning caused the development of either phalloidin- or gyromitrin-intoxication syndromes (after consumption of Amanita phalloides and Gyromitra esculenta respectively). It is emphasized that the forensic medical experts must substantiate the diagnosis of poisoning with mushroom toxins based on the results of the chemical-toxicological and/or forensic chemical investigations. The relevant materials taken from the victim or the corpse should be dispatched for analysis not only within the first day but also on days 2-4 after intoxication. The mycological and genetic analysis must include the detection and identification of mushroom microparticles and spores in the smears from the oral cavity, vomiting matter, wash water, gastric and intestinal contents. In addition, the macro- and microscopic morphological signs, clinical data (major syndromes, results of laboratory studies, methods of treatment) should be taken into consideration as well as the time (season) of mushroom gathering, simultaneous poisoning in a group of people, and other pertinent information. PMID:27030094

  2. Building a diagnostic algorithm on localized neuropathic pain (LNP) and targeted topical treatment: focus on 5% lidocaine-medicated plaster

    PubMed Central

    Casale, Roberto; Mattia, Consalvo

    2014-01-01

    Within the broad definition of neuropathic pain, the refinement of clinical diagnostic procedures has led to the introduction of the concept of localized neuropathic pain (LNP). It is characterized by consistent and circumscribed area(s) of maximum pain, which are associated with negative or positive sensory signs and/or spontaneous symptoms typical of neuropathic pain. This description outlines the clinical features (currently lacking in guidelines and treatment recommendations) in patients for whom topical targeted treatment with 5% lidocaine-medicated plaster is suggested as first-line therapy. Few epidemiologic data are present in the literature but it is generally estimated that about 60% of neuropathic pain conditions are localized, and therefore identifiable as LNP. A mandatory clinical criterion for the diagnosis of LNP is that signs and symptoms must be present in a clearly identified and defined area(s). Cartographic recordings can help to define each area and to assess variations. The diagnosis of LNP relies on careful neurological examination more than on pain questionnaires, but it is recognized that they can be extremely useful for recording the symptom profiles and establishing a more targeted treatment. The most widely studied frequent/relevant clinical presentations of LNP are postherpetic neuralgia, diabetic neuropathy, and neuropathic postoperative pain. They successfully respond to treatment with 5% lidocaine-medicated plaster with equal if not better pain control but with fewer side effects versus conventional systemic treatments. Generally, the more localized the pain (ie, the area of an A4 sheet of paper) the better the results of topical treatment. This paper proposes an easy-to-understand algorithm to identify patients with LNP and to guide targeted topical treatments with 5% lidocaine medicated plaster. PMID:24790451

  3. Medical Imaging.

    ERIC Educational Resources Information Center

    Barker, M. C. J.

    1996-01-01

    Discusses four main types of medical imaging (x-ray, radionuclide, ultrasound, and magnetic resonance) and considers their relative merits. Describes important recent and possible future developments in image processing. (Author/MKR)

  4. Automatic segmentation of medical images using image registration: diagnostic and simulation applications.

    PubMed

    Barber, D C; Hose, D R

    2005-01-01

    Automatic identification of the boundaries of significant structure (segmentation) within a medical image is an are of ongoing research. Various approaches have been proposed but only two methods have achieved widespread use: manual delineation of boundaries and segmentation using intensity values. In this paper we describe an approach based on image registration. A reference image is prepared and segmented, by hand or otherwise. A patient image is registered to the reference image and the mapping then applied to ther reference segmentation to map it back to the patient image. In general a high-resolution nonlinear mapping is required to achieve accurate segmentation. This paper describes an algorithm that can efficiently generate such mappings, and outlines the uses of this tool in two relevant applications. An important feature of the approach described in this paper is that the algorithm is independent of the segmentation problem being addresses. All knowledge about the problem at hand is contained in files of reference data. A secondary benefit is that the continuous three-dimensional mapping generated is well suited to the generation of patient-specific numerical models (e.g. finite element meshes) from the library models. Smoothness constraints in the morphing algorithm tend to maintain the geometric quality of the reference mesh. PMID:15804853

  5. Ultrasound-guided greater occipital nerve blocks and pulsed radiofrequency ablation for diagnosis and treatment of occipital neuralgia.

    PubMed

    Vanderhoek, Matthew David; Hoang, Hieu T; Goff, Brandon

    2013-09-01

    Occipital neuralgia is a condition manifested by chronic occipital headaches and is thought to be caused by irritation or trauma to the greater occipital nerve (GON). Treatment for occipital neuralgia includes medications, nerve blocks, and pulsed radiofrequency ablation (PRFA). Landmark-guided GON blocks are the mainstay in both the diagnosis and treatment of occipital neuralgia. Ultrasound is being utilized more and more in the chronic pain clinic to guide needle advancement when performing procedures; however, there are no reports of ultrasound used to guide a diagnostic block or PRFA of the GON. We report two cases in which ultrasound was used to guide diagnostic greater occipital nerve blocks and greater occipital nerve pulsed radiofrequency ablation for treatment of occipital neuralgia. Two patients with occipital headaches are presented. In Case 1, ultrasound was used to guide diagnostic blocks of the greater occipital nerves. In Case 2, ultrasound was utilized to guide placement of radiofrequency probes for pulsed radiofrequency ablation of the greater occipital nerves. Both patients reported immediate, significant pain relief, with continued pain relief for several months. Further study is needed to examine any difference in outcomes or morbidity between the traditional landmark method versus ultrasound-guided blocks and pulsed radiofrequency ablation of the greater occipital nerves. PMID:24282778

  6. Diagnostic Imaging

    MedlinePlus

    Diagnostic imaging lets doctors look inside your body for clues about a medical condition. A variety of machines and ... and activities inside your body. The type of imaging your doctor uses depends on your symptoms and ...

  7. Progress in developing a thermal method for measuring the output power of medical ultrasound transducers that exploits the pyroelectric effect.

    PubMed

    Zeqiri, Bajram; Zauhar, Gordana; Hodnett, Mark; Barrie, Jill

    2011-05-01

    Progress in developing a new measurement method for ultrasound output power is described. It is a thermal-based technique with the acoustic power generated by a transducer being absorbed within a specially developed polyurethane rubber material, whose high absorption coefficient ensures energy deposition within a few mm of the ultrasonic wave entering the material. The rate of change of temperature at the absorber surface is monitored using the pyroelectric voltage generated from electrodes disposed either side of a 60 mm diameter, 0.061 mm thick membrane of the piezoelectric polymer polyvinylidene fluoride (pvdf) bonded to the absorber. The change in the pyroelectric output voltage generated by the sensor when the transducer is switched ON and OFF is proportional to the delivered ultrasound power. The sensitivity of the device is defined as the magnitude of these switch voltages to a unit input stimulus of power (watt). Three important aspects of the performance of the pyroelectric sensor have been studied. Firstly, measurements have revealed that the temperature dependent sensitivity increases over the range from approximately 20°C to 30°C at a rate of +1.6% °C(-1). Studies point to the key role that the properties of both the absorbing backing layer and pvdf membrane play in controlling the sensor response. Secondly, the high sensitivity of the technique has been demonstrated using an NPL Pulsed Checksource, a 3.5 MHz focused transducer delivering a nominal acoustic power level of 4 mW. Finally, proof-of-concept of a new type of acoustic sensor responding to time-averaged intensity has been demonstrated, through fabrication of an absorber-backed hydrophone of nominal active element diameter 0.4 mm. A preliminary study using such a device to resolve the spatial distribution of acoustic intensity within plane-piston and focused 3.5 MHz acoustic fields has been completed. Derived beam profiles are compared to conventional techniques that depend on deriving

  8. High dynamic range pixel architecture for advanced diagnostic medical x-ray imaging applications

    SciTech Connect

    Izadi, Mohammad Hadi; Karim, Karim S.

    2006-05-15

    The most widely used architecture in large-area amorphous silicon (a-Si) flat panel imagers is a passive pixel sensor (PPS), which consists of a detector and a readout switch. While the PPS has the advantage of being compact and amenable toward high-resolution imaging, small PPS output signals are swamped by external column charge amplifier and data line thermal noise, which reduce the minimum readable sensor input signal. In contrast to PPS circuits, on-pixel amplifiers in a-Si technology reduce readout noise to levels that can meet even the stringent requirements for low noise digital x-ray fluoroscopy (<1000 noise electrons). However, larger voltages at the pixel input cause the output of the amplified pixel to become nonlinear thus reducing the dynamic range. We reported a hybrid amplified pixel architecture based on a combination of PPS and amplified pixel designs that, in addition to low noise performance, also resulted in large-signal linearity and consequently higher dynamic range [K. S. Karim et al., Proc. SPIE 5368, 657 (2004)]. The additional benefit in large-signal linearity, however, came at the cost of an additional pixel transistor. We present an amplified pixel design that achieves the goals of low noise performance and large-signal linearity without the need for an additional pixel transistor. Theoretical calculations and simulation results for noise indicate the applicability of the amplified a-Si pixel architecture for high dynamic range, medical x-ray imaging applications that require switching between low exposure, real-time fluoroscopy and high-exposure radiography.

  9. Ultrasound imaging in the general practitioner's office – a literature review

    PubMed Central

    Ryk, Małgorzata; Suwała, Magdalena; Żurakowska, Tatiana; Kosiak, Wojciech

    2016-01-01

    Ultrasound, which is a safe and non-invasive diagnostic modality that uses more and more advanced imaging techniques, has become the first-choice examination in various diseases. It is more and more often used in the general practitioner's office to supplement physical examination and interview. Aim The aim of this paper is to review the Polish medical literature pertaining to the usage of ultrasound imaging in general practice as well as to present advantages, disadvantages and utility associated with conducting ultrasound examinations by general practitioners based on selected publications. Material and methods The analysis involved 15 articles found in Polish medical literature published in 1994–2013 in 9 medical journals. These publications were obtained using various data bases, such as Polish Medical Bibliography, Google Scholar as well as websites of “Lekarz Rodzinny” and “Ultrasonografia.” Results Of 15 available publications, 5 papers present the usage of ultrasound imaging by a primary care physician for general purposes, 4 discuss the usage of abdominal scans, 3 – imaging of the neck and lymph nodes, 1 – lungs, and 2 discuss its usage for specific disease entities. In over 70% of the papers, the financial aspect associated with the usage of this modality in general practice is mentioned. More than a half of the publications draw attention to the possibility of using point-of-care ultrasound examinations. Advantages of ultrasonography most often mentioned by the authors include: good effects of screening, safety, short duration and low cost. The authors of eight publications also indicate disadvantages associated with ultrasound imaging used by a general practitioner. Conclusions In the Polish literature, there are relatively few papers on the role of ultrasonography in the office of a primary care physician. This modality is more and more often becoming a tool that helps primary care physicians to establish diagnoses, accelerates the

  10. Assessment of ultrasound as a diagnostic modality for detecting potentially unstable cervical spine fractures in pediatric severe traumatic brain injury: A feasibility study

    PubMed Central

    Agrawal, Deepak; Sinha, Tej Prakash; Bhoi, Sanjeev

    2015-01-01

    Background: Early cervical spine clearance is extremely important in unconscious trauma patients and may be difficult to achieve in emergency setting. Objectives: The aim of this study was to assess the feasibility of standard portable ultrasound in detecting potentially unstable cervical spine injuries in severe traumatic brain injured (TBI) patients during initial resuscitation. Materials and Methods: This retro-prospective pilot study carried out over 1-month period (June–July 2013) after approval from the institutional ethics committee. Initially, the technique of cervical ultrasound was standardized by the authors and tested on ten admitted patients of cervical spine injury. To assess feasibility in the emergency setting, three hemodynamically stable pediatric patients (≦18 years) with isolated severe head injury (Glasgow coma scale ≤8) coming to emergency department underwent an ultrasound examination. Results: The best window for the cervical spine was through the anterior triangle using the linear array probe (6–13 MHz). In the ten patients with documented cervical spine injury, bilateral facet dislocation at C5–C6 was seen in 4 patients and at C6–C7 was seen in 3 patients. C5 burst fracture was present in one and cervical vertebra (C2) anterolisthesis was seen in one patient. Cervical ultrasound could easily detect fracture lines, canal compromise and ligamental injury in all cases. Ultrasound examination of the cervical spine was possible in the emergency setting, even in unstable patients and could be done without moving the neck. Conclusions: Cervical ultrasound may be a useful tool for detecting potentially unstable cervical spine injury in TBI patients, especially those who are hemodynamically unstable. PMID:26167212

  11. Endoscopic ultrasound

    MedlinePlus

    Endoscopic ultrasound is a type of imaging test. It is used to see organs in and near the digestive ... Ultrasound is a way to see the inside of the body using high-frequency sound waves. Endoscopic ...

  12. Scrotal ultrasound

    MedlinePlus

    ... the scrotal sac to help transmit the sound waves. A handheld probe (the ultrasound transducer) is then ... The ultrasound machine sends out high-frequency sound waves. These waves reflect off areas in the scrotum ...

  13. Pregnancy ultrasound

    MedlinePlus

    ... 3D ultrasound References Richards DS. Obstetrical ultrasound: Imaging, dating, and growth. In: Gabbe SG, Niebyl JR, Simpson ... the first to achieve this important distinction for online health information and services. Learn more about A. ...

  14. 21 CFR 890.5860 - Ultrasound and muscle stimulator.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ultrasound and muscle stimulator. 890.5860 Section... Ultrasound and muscle stimulator. (a) Ultrasound and muscle stimulator for use in applying therapeutic deep heat for selected medical conditions—(1) Identification. An ultrasound and muscle stimulator for use...

  15. 21 CFR 890.5860 - Ultrasound and muscle stimulator.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Ultrasound and muscle stimulator. 890.5860 Section... Ultrasound and muscle stimulator. (a) Ultrasound and muscle stimulator for use in applying therapeutic deep heat for selected medical conditions—(1) Identification. An ultrasound and muscle stimulator for use...

  16. 21 CFR 890.5860 - Ultrasound and muscle stimulator.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Ultrasound and muscle stimulator. 890.5860 Section... Ultrasound and muscle stimulator. (a) Ultrasound and muscle stimulator for use in applying therapeutic deep heat for selected medical conditions—(1) Identification. An ultrasound and muscle stimulator for use...

  17. 21 CFR 890.5860 - Ultrasound and muscle stimulator.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Ultrasound and muscle stimulator. 890.5860 Section... Ultrasound and muscle stimulator. (a) Ultrasound and muscle stimulator for use in applying therapeutic deep heat for selected medical conditions—(1) Identification. An ultrasound and muscle stimulator for use...

  18. 21 CFR 890.5860 - Ultrasound and muscle stimulator.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ultrasound and muscle stimulator. 890.5860 Section... Ultrasound and muscle stimulator. (a) Ultrasound and muscle stimulator for use in applying therapeutic deep heat for selected medical conditions—(1) Identification. An ultrasound and muscle stimulator for use...

  19. Acousto-optic-tunable-filter-based spectropolarimetric imagers for medical diagnostic applications--instrument design point of view.

    PubMed

    Gupta, Neelam

    2005-01-01

    Compact optical imagers that can detect both spectral and polarization signatures are required in many biomedical applications. An acousto-optic-tunable-filter (AOTF)-based imager is ideally suited to provide both agile spectral and polarization signatures. Such an imager can be readily used for real-time in vivo medical diagnostic applications. We develop a family of small, robust, and programmable hyperspectral imagers operating from the ultraviolet (UV) to the long-wave IR (LWIR). Such imagers require minimal data processing because they can acquire images at only select wavelengths of interest. We use AOTFs made of KDP, TeO2, and TAS with Si-based CCD, InGaAs, InSb, and HgCdTe cameras to cover different spectral regions from the UV to the LWIR. Operation of each of these imagers and image acquisition is computer controlled. The most developed imager covers the visible to near-infrared (VNIR) region from 400 to 900 nm, with a 10-nm spectral resolution at 600 nm, it uses an electronically tunable TeO2 AOTF as a bandpass filter, and a nematic liquid crystal retarder to change polarization. We describe our concept in the development of these imagers and present new results obtained using the VNIR imager. PMID:16292960

  20. Safety in numbers 2: Competency modelling and diagnostic error assessment in medication dosage calculation problem-solving.

    PubMed

    Weeks, Keith W; Hutton, B Meriel; Young, Simon; Coben, Diana; Clochesy, John M; Pontin, David

    2013-03-01

    Accurately defining and modelling competence in medication dosage calculation problem-solving (MDC-PS) is a fundamental pre-requisite to measuring competence, diagnosing errors and determining the necessary design and content of professional education programmes. In this paper we advance an MDC-PS competence model that illustrates the relationship between conceptual competence (dosage problem-understanding), calculation competence (dosage-computation) and technical measurement competence (dosage-measurement). To facilitate bridging of the theory-practice gap it is critical that such models are operationalised within a wider education framework that supports the learning, assessment and synthesis of cognitive competence (the knowing that and knowing why of MDC-PS) and functional competence (the know-how and skills associated with the professional practice of MDC-PS in clinical settings). Within the context of supporting the learning and diagnostic assessment of MDC-PS we explore PhD fieldwork that challenges the value of pedagogical approaches that focus solely on abstract information, that isolate the process of knowledge construction from its application in practice settings and contribute to the generation of conceptual errors. We consider misconceptions theory and the concept of mathematical 'dropped stitches' and offer an assessment model and program designed to diagnose flawed arithmetical operation and computation constructs. PMID:23276625

  1. A CMUT probe for medical ultrasonography: from microfabrication to system integration.

    PubMed

    Savoia, Alessandro Stuart; Calianov, Giosuè; Pappalardo, Massimo

    2012-06-01

    Medical ultrasonography is a powerful and cost-effective diagnostic technique. To date, high-end medical imaging systems are able to efficiently implement real-time image formation techniques that can dramatically improve the diagnostic capabilities of ultrasound. Highly performing and thermally efficient ultrasound probes are then required to successfully enable the most advanced techniques. In this context, ultrasound transducer technology is the current limiting factor. Capacitive micromachined ultrasonic transducers (CMUTs) are micro-electro-mechanical systems (MEMS)-based devices that have been widely recognized as a valuable alternative to piezoelectric transducer technology in a variety of medical imaging applications. Wideband operation, good thermal efficiency, and low fabrication cost, especially for those applications requiring high-volume production of small-area dice, are strength factors that may justify the adoption of this MEMS technology in the medical ultrasound imaging field. This paper presents the design, development, fabrication, and characterization of a 12-MHz ultrasound probe for medical imaging, based on a CMUT array. The CMUT array is microfabricated and packed using a novel fabrication concept specifically conceived for imaging transducer arrays. The performance of the developed probe is optimized by including analog front-end reception electronics. Characterization and imaging results are used to assess the performance of CMUTs with respect to conventional piezoelectric transducers. PMID:22711408

  2. Medical X-Rays

    MedlinePlus

    ... Diagnostic X-Ray Equipment Compliance Program Guidance Manual CP 7386.003 Field Compliance Testing of Diagnostic (Medical) ... and Exporting Electronic Products Compliance Program Guidance Manual CP 7386.003 Field Compliance Testing of Diagnostic (Medical) ...

  3. What's new in urologic ultrasound?

    PubMed

    Lal, Anupam; Naranje, Priyanka; Pavunesan, Santhosh Kumar

    2015-01-01

    Ultrasound is an imaging technology that has evolved swiftly and has come a long way since its beginnings. It is a commonly used initial diagnostic imaging modality as it is rapid, effective, portable, relatively inexpensive, and causes no harm to human health. In the last few decades, there have been significant technological improvements in the equipment as well as the development of contrast agents that allowed ultrasound to be even more widely adopted for urologic imaging. Ultrasound is an excellent guidance tool for an array of urologic interventional procedures and also has therapeutic application in the form of high-intensity focused ultrasound (HIFU) for tumor ablation. This article focuses on the recent advances in ultrasound technology and its emerging clinical applications in urology. PMID:26166960

  4. [The use of physiotherapy tools in medical treatment. The use of heat, light, electric, magnetic, ultrasound and shock wave therapy as well as medical massage in Hungarian medical practice].

    PubMed

    Bálint, Géza; Bálint, Péter

    2013-12-01

    The authors overview the possible use of different modalities of passive physiotherapy in the Hungarian medical practice. These modalities can be used in most of the medical specialities as well as family practice, not only in the treatment of the musculoskeletal disorders and medical rehabilitation. PMID:24273289

  5. [High frequency ultrasound].

    PubMed

    Sattler, E

    2015-07-01

    Diagnostic ultrasound has become a standard procedure in clinical dermatology. Devices with intermediate high frequencies of 7.5-15 MHz are used in dermato-oncology for the staging and postoperative care of skin tumor patients and in angiology for improved vessel diagnostics. In contrast, the high frequency ultrasound systems with 20-100 MHz probes offer a much higher resolution, yet with a lower penetration depth of about 1 cm. The main indications are the preoperative measurements of tumor thickness in malignant melanoma and other skin tumors and the assessment of inflammatory and soft tissue diseases, offering information on the course of these dermatoses and allowing therapy monitoring. This article gives an overview on technical principles, devices, mode of examination, influencing factors, interpretation of the images, indications but also limitations of this technique. PMID:25636803

  6. Ultrasound techniques in the evaluation of the mediastinum, part I: endoscopic ultrasound (EUS), endobronchial ultrasound (EBUS) and transcutaneous mediastinal ultrasound (TMUS), introduction into ultrasound techniques

    PubMed Central

    Annema, Jouke Tabe; Clementsen, Paul; Cui, Xin Wu; Borst, Mathias Maximilian; Jenssen, Christian

    2015-01-01

    Ultrasound imaging has gained importance in pulmonary medicine over the last decades including conventional transcutaneous ultrasound (TUS), endoscopic ultrasound (EUS), and endobronchial ultrasound (EBUS). Mediastinal lymph node staging affects the management of patients with both operable and inoperable lung cancer (e.g., surgery vs. combined chemoradiation therapy). Tissue sampling is often indicated for accurate nodal staging. Recent international lung cancer staging guidelines clearly state that endosonography (EUS and EBUS) should be the initial tissue sampling test over surgical staging. Mediastinal nodes can be sampled from the airways [EBUS combined with transbronchial needle aspiration (EBUS-TBNA)] or the esophagus [EUS fine needle aspiration (EUS-FNA)]. EBUS and EUS have a complementary diagnostic yield and in combination virtually all mediastinal lymph nodes can be biopsied. Additionally endosonography has an excellent yield in assessing granulomas in patients suspected of sarcoidosis. The aim of this review, in two integrative parts, is to discuss the current role and future perspectives of all ultrasound techniques available for the evaluation of mediastinal lymphadenopathy and mediastinal staging of lung cancer. A specific emphasis will be on learning mediastinal endosonography. Part I is dealing with an introduction into ultrasound techniques, mediastinal lymph node anatomy and diagnostic reach of ultrasound techniques and part II with the clinical work up of neoplastic and inflammatory mediastinal lymphadenopathy using ultrasound techniques and how to learn mediastinal endosonography. PMID:26543620

  7. The differentiation of the character of solid lesions in the breast in the compression sonoelastography. Part I: The diagnostic value of the ultrasound B-mode imaging in the differentiation diagnostics of solid, focal lesions in the breast in relation to the pathomorphological verification

    PubMed Central

    2012-01-01

    The aim of this study was to evaluate the diagnostic value of the ultrasound B-mode imaging in the differentiation diagnostics of solid lesions in the breast in relation to the pathomorphological verification. From January to July 2010, 375 ultrasound breast examinations were conducted. The study enrolled 80 women aged 17–83, with 99 solid, focal lesions present in breasts, which were qualified for pathomorphological verification on the basis of the ultrasound examination. All patients underwent: the interview, physical examination, ultrasound examination and sonoelastography. The ultrasound features of the lesions, their vascularization patterns in the Doppler examination as well as the adjacent tissues were determined. Next, the focal lesions were categorized according to the BIRADS-US classification. The obtained results were analyzed statistically. In the group of 80 patients, 99 focal, solid lesions in breasts were visualized, including 39 neoplastic, malignant lesions (group I) and 60 lesions of benign nature (group II). The malignant lesions were often characterized by: greater size, irregular shape (34/39), prevalence of the anteroposterior dimension over the lateral-lateral dimension (22/39), acoustic shadowing (20/39), the margins not well-circumscribed (37/39), spiculated margins (16/39) and the presence of calcifications (14/39). The benign lesions were much more often hyper- and isoechogenic (14/60). In group I the lesions more often demonstrated the features of increased vascularization (29/39) and the presence of irregularly shaped vessels (23/29). This vascularization more often originated in the adjacent tissues. In the surroundings of the malignant neoplastic lesions, the presence of edema (16/39) and skin thickening (6/39) occurred more frequently and the abnormal axillary lymph nodes were more often diagnosed. The lesions of group I were assigned to the following BIRADS categories: BIRADS-US 4 (9 lesions) and BIRADS-US 5 (30 lesions). In group

  8. Solid cancer incidence among Chinese medical diagnostic x-ray workers, 1950-1995: Estimation of radiation-related risks.

    PubMed

    Sun, Zhijuan; Inskip, Peter D; Wang, Jixian; Kwon, Deukwoo; Zhao, Yongcheng; Zhang, Liangan; Wang, Qin; Fan, Saijun

    2016-06-15

    The objective of this study was to estimate solid cancer risk attributable to long-term, fractionated occupational exposure to low doses of ionizing radiation. Based on cancer incidence for the period 1950-1995 in a cohort of 27,011 Chinese medical diagnostic X-ray workers and a comparison cohort of 25,782 Chinese physicians who did not use X-ray equipment in their work, we used Poisson regression to fit excess relative risk (ERR) and excess absolute risk (EAR) dose-response models for incidence of all solid cancers combined. Radiation dose reconstruction was based on a previously published method that relied on simulating measurements for multiple X-ray machines, workplaces and working conditions, information about protective measures, including use of lead aprons, and work histories. The resulting model was used to estimate calendar year-specific badge dose calibrated as personal dose equivalent (Sv). To obtain calendar year-specific colon doses (Gy), we applied a standard organ conversion factor. A total of 1,643 cases of solid cancer were identified in 1.45 million person-years of follow-up. In both ERR and EAR models, a statistically significant radiation dose-response relationship was observed for solid cancers as a group. Averaged over both sexes, and using colon dose as the dose metric, the estimated ERR/Gy was 0.87 (95% CI: 0.48, 1.45), and the EAR was 22 per 10(4)PY-Gy (95% CI: 14, 32) at age 50. We obtained estimates of the ERR and EAR of solid cancers per unit dose that are compatible with those derived from other populations chronically exposed to low dose-rate occupational or environmental radiation. PMID:26860236

  9. Capturing and displaying microscopic images used in medical diagnostics and forensic science using 4K video resolution - an application in higher education.

    PubMed

    Maier, Hans; de Heer, Gert; Ortac, Ajda; Kuijten, Jan

    2015-11-01

    To analyze, interpret and evaluate microscopic images, used in medical diagnostics and forensic science, video images for educational purposes were made with a very high resolution of 4096 × 2160 pixels (4K), which is four times as many pixels as High-Definition Video (1920 × 1080 pixels). The unprecedented high resolution makes it possible to see details that remain invisible to any other video format. The images of the specimens (blood cells, tissue sections, hair, fibre, etc.) are recorded using a 4K video camera which is attached to a light microscope. After processing, this resulted in very sharp and highly detailed images. This material was then used in education for classroom discussion. Spoken explanation by experts in the field of medical diagnostics and forensic science was also added to the high-resolution video images to make it suitable for self-study. PMID:26250075

  10. Therapeutic ultrasound: Recent trends and future perspectives

    NASA Astrophysics Data System (ADS)

    Crum, Lawrence; Bailey, Michael; Hwang, Joo Ha; Khokhlova, Vera; Sapozhnikov, Oleg

    2010-01-01

    Before ultrasound-imaging systems became widely available, ultrasound therapy devices showed great promise for general use in medicine. However, it is only in the last decade that ultrasound therapy has begun to obtain clinical acceptance. Recently, a variety of novel applications of therapeutic ultrasound have been developed that include sonothrombolysis, site-specific and ultrasound-mediated drug delivery, shock wave therapy, lithotripsy, tumor ablation, acoustic hemostasis and several others. This paper reviews a few selected applications of therapeutic ultrasound. It will address some of the basic scientific questions and future challenges in developing these methods and technologies for general use in our society. As a plenary presentation, its audience is intended for the ultrasound scientist or engineer, and thus is not presented at the level of the experienced medical ultrasound professional.

  11. [Periostal interposition in epiphysiolysis, diagnosed by ultrasound].

    PubMed

    Ostergård, L L; Gaster, P; Hjarbaek, J

    2000-06-01

    Musculoskeletal ultrasound is a rapidly expanding diagnostic field. High frequency transducers with high spacial resolution make it possible to demonstrate superficial soft tissue structures such as tendons, muscles, ligaments and even, under certain circumstances, fractures and periosteum. A case is presented where ultrasound clearly visualised periostal interposition in a distal tibial epiphysiolysis in an eight year-old boy, and some aspects of ultrasound in musculo-skeletal imaging are discussed. PMID:10895603

  12. Interventional ultrasound

    SciTech Connect

    Holm, H.H.; Kristensen, J.K.

    1985-01-01

    This book discusses: Introduction to interventional ultrasound/handling of aspirated material/general principles of fine needle aspiration cytology/procedure and principles in ultrasonically guided puncture/puncture of focal liver lesions/intraoperative puncture of the liver guided by ultrasound/Interventional ultrasound in cancer therapy/Interventional echocardiography/Fine-needle aspiration biopsy: Are there any risks./Puncture of renal mass lesions/Intrauterine needle diagnosis/Percutaneous nephrolithotomy.

  13. Vaginal ultrasound in assisted reproduction.

    PubMed

    Wikland, M

    1992-06-01

    Vaginal scanning of the ovaries and the uterus is a diagnostic and monitoring tool of utmost importance in assisted conception. Although the value of ultrasound for monitoring follicular growth has been questioned, few groups working on assisted conception do not use it. Follicle aspiration under the guidance of vaginal sonography is the method of choice. With such a simple and safe technique available, using laparoscopy for retrieving oocytes for assisted conception cannot be justified. The introduction of ultrasound-guided transvaginal retrograde tubal catheterization has meant that laparoscopic GIFT and ZIFT procedures will probably soon be unnecessary. Vaginal sonography is one of the most clinically important diagnostic instruments in assisted conception. PMID:1424325

  14. [Ultrasound in the management of inflammatory dermatosis].

    PubMed

    Habicheyn Hiar, S; Segura Palacios, J M; Bernal Ruiz, A I

    2015-11-01

    Cutaneous ultrasound is a dermatological diagnostic imaging technique based on the interaction of high-frequency ultrasounds with the skin. Because it is non-invasive, rapid and accessible, it has increasingly wide clinical applications. This article reviews its use in the management of inflammatory dermatological diseases. PMID:26895938

  15. Ultrasound in space

    NASA Technical Reports Server (NTRS)

    Martin, David S.; South, Donna A.; Garcia, Kathleen M.; Arbeille, Philippe

    2003-01-01

    Physiology of the human body in space has been a major concern for space-faring nations since the beginning of the space era. Ultrasound (US) is one of the most cost effective and versatile forms of medical imaging. As such, its use in characterizing microgravity-induced changes in physiology is being realized. In addition to the use of US in related ground-based studies, equipment has also been modified to fly in space. This involves alteration to handle the stresses of launch and different power and cooling requirements. Study protocols also have been altered to accommodate the microgravity environment. Ultrasound studies to date have shown a pattern of adaptation to microgravity that includes changes in cardiac chamber sizes and vertebral spacing. Ultrasound has been and will continue to be an important component in the investigation of physiological and, possibly, pathologic changes occurring in space or as a result of spaceflight.

  16. Emergency department bedside ultrasound diagnosis of retinoblastoma in a child.

    PubMed

    Presley, Bradley C; Flannigan, Matthew J

    2013-10-01

    A 30-month-old boy presented to a Haitian emergency department with proptosis, periorbital edema, and progressive blindness. Bedside ultrasound examination revealed bilateral ocular masses with dense calcifications pathognomonic for retinoblastoma. This case illustrates the diagnostic utility of bedside ultrasound for an advanced case of retinoblastoma in a resource-poor setting. Ocular ultrasound technique is also reviewed. PMID:24084617

  17. Ultrasound imaging as an undergraduate physics laboratory exercise

    NASA Astrophysics Data System (ADS)

    Stiles, Timothy A.

    2014-05-01

    Ultrasound imaging provides an interesting and accessible example of the intersection between biology, medicine, and physics. This article provides a review of the physics and technology currently available and discusses two recent methods that have expanded the diagnostic capabilities of ultrasound imaging. We also describe two undergraduate physics laboratory exercises involving ultrasound imaging.

  18. A single-chip 32-channel analog beamformer with 4-ns delay resolution and 768-ns maximum delay range for ultrasound medical imaging with a linear array transducer.

    PubMed

    Um, Ji-Yong; Kim, Yoon-Jee; Cho, Seong-Eun; Chae, Min-Kyun; Kim, Byungsub; Sim, Jae-Yoon; Park, Hong-June

    2015-02-01

    A single-chip 32-channel analog beamformer is proposed. It achieves a delay resolution of 4 ns and a maximum delay range of 768 ns. It has a focal-point based architecture, which consists of 7 sub-analog beamformers (sub-ABF). Each sub-ABF performs a RX focusing operation for a single focal point. Seven sub-ABFs perform a time-interleaving operation to achieve the maximum delay range of 768 ns. Phase interpolators are used in sub-ABFs to generate sampling clocks with the delay resolution of 4 ns from a low frequency system clock of 5 MHz. Each sub-ABF samples 32 echo signals at different times into sampling capacitors, which work as analog memory cells. The sampled 32 echo signals of each sub-ABF are originated from one target focal point at one instance. They are summed at one instance in a sub-ABF to perform the RX focusing for the target focal point. The proposed ABF chip has been fabricated in a 0.13- μ m CMOS process with an active area of 16 mm (2). The total power consumption is 287 mW. In measurement, the digital echo signals from a commercial ultrasound medical imaging machine were applied to the fabricated chip through commercial DAC chips. Due to the speed limitation of the DAC chips, the delay resolution was relaxed to 10 ns for the real-time measurement. A linear array transducer with no steering operation is used in this work. PMID:25069119

  19. A New Scheme for Curved Needle Segmentation in Three-Dimensional Ultrasound Images

    PubMed Central

    Aboofazeli, Mohammad; Abolmaesumi, Purang; Mousavi, Parvin; Fichtinger, Gabor

    2010-01-01

    Ultrasound image guided needle insertion is the method of choice for a wide variety of medical diagnostic and therapeutic procedures. When flexible needles are inserted in soft tissue, these needles generally follow a curved path. Segmenting the trajectory of the needles in ultrasound images will facilitate guiding them within the tissue. In this paper, a novel algorithm for curved needle segmentation in three-dimensional (3D) ultrasound images is presented. The algorithm is based on the projection of a filtered 3D image onto a two-dimensional (2D) image. Detection of the needle in the resulting 2D image determines a surface on which the needle is located. The needle is then segmented on the surface. The proposed technique is able to detect needles without any previous assumption about the needle shape, or any a priori knowledge about the needle insertion axis line. PMID:20563242

  20. Evaluating the Use of a Negative D-Dimer and Modified Low Wells Score in Excluding above Knee Deep Venous Thrombosis in an Outpatient Population, Assessing Need for Diagnostic Ultrasound

    PubMed Central

    Rastogi, Anshul; Prabhudesai, Shirish; Mcclinton, David; MacCallum, Peter; Platton, Sean; Friedman, Emma

    2014-01-01

    Aims. Colour doppler ultrasonography (CDUS) is widely used in the diagnosis of deep venous thrombosis (DVT); however, the number of scans positive for above knee DVT is low. The present study evaluates the reliability of the D-dimer test combined with a clinical probability score (Wells score) in ruling out an above knee DVT and identifying patients who do not need a CDUS. Materials and Method. This study is a retrospective audit and reaudit of a total of 816 outpatients presenting with suspected lower limb DVT from March 2009 to March 2010 and from September 2011 to February 2012. Following the initial audit, a revised clinical diagnostic pathway was implemented. Results. In our initial audit, seven patients (4.9%) with a negative D-dimer and a low Wells score had a DVT. On review, all seven had a risk factor identified that was not included in the Wells score. No patient with negative D-dimer and low Wells score with no extra clinical risk factor had a DVT on CDUS (negative predictive value 100%). A reaudit confirmed adherence to our revised clinical diagnostic pathway. Conclusions. A negative D-dimer together with a low Wells score and no risk factors effectively excludes a lower limb DVT and an ultrasound is unnecessary in these patients. PMID:24967296