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 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

  14. 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

  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. [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

  8. 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.

  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 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 ...

  5. 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 ...

  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. 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...

  19. 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...

  20. 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,…

  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. 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.

  11. 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

  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

    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 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

  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. 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

  2. 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.

  3. 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

  4. 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.

  5. 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

  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 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

  8. 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

  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.