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Sample records for modern ultrasound techniques

  1. Clinical application of modern ultrasound techniques after liver transplantation.

    PubMed

    Teegen, Eva Maria; Denecke, Timm; Eisele, Robert; Lojewski, Christian; Neuhaus, Peter; Chopra, Sascha Santosh

    2016-10-01

    Liver transplantation has been established as a first-line therapy for a number of indications. Conventional ultrasound and contrast-enhanced ultrasound (CEUS) are methods of choice during the postoperative period as a safe and fast tool to detect potential complications and to enable early intervention if necessary. CEUS increases diagnostic quality and is an appropriate procedure for the examination of vessels and possibly bile ducts. This article presents the state of the art of ultrasound application during the early period after liver transplantation. It addresses common vascular complications and describes the identification of postoperative abnormal findings using ultrasound and CEUS.

  2. Modern spectral analysis techniques for blood flow velocity and spectral measurements with pulsed Doppler ultrasound.

    PubMed

    David, J Y; Jones, S A; Giddens, D P

    1991-06-01

    Four spectral analysis techniques were applied to pulsed Doppler ultrasonic quadrature signals to compare the relative merits of each technique for estimation of flow velocity and Doppler spectra. The four techniques were 1) the fast Fourier transform method, 2) the maximum likelihood method, 3) the Burg autoregressive algorithm, and 4) the modified covariance approach to autoregressive modeling. Both simulated signals and signals obtained from an in vitro flow system were studied. Optimal parameter values (e.g., model orders) were determined for each method, and the effects of signal-to-noise ratio and signal bandwidth were investigated. The modern spectral analysis techniques were shown to be superior to Fourier techniques in most circumstances, provided the model order was chosen appropriately. Robustness considerations tended to recommend the maximum likelihood method for both velocity and spectral estimation. Despite the restrictions of steady laminar flow, the results provide important basic information concerning the applicability of modern spectral analysis techniques to Doppler ultrasonic evaluation of arterial disease.

  3. Robert's uterus: modern imaging techniques and ultrasound-guided hysteroscopic treatment without laparoscopy or laparotomy.

    PubMed

    Ludwin, A; Ludwin, I; Martins, W P

    2016-10-01

    Robert's uterus is a unique malformation, described as a septate uterus with a non-communicating hemicavity, consisting of a blind uterine horn usually with unilateral hematometra, a contralateral unicornuate uterine cavity and a normally shaped external uterine fundus. The main symptom in affected young women is pelvic pain that becomes intensified near menses. We describe the case of a 22-year-old woman who was referred for diagnostic assessment and treatment of a congenital uterine anomaly. We used three-dimensional sonohysterography with volume-contrast imaging, HDLive rendering mode and automatic volume calculation (SonoHysteroAVC) for the diagnosis, surgical planning and postoperative evaluation. These imaging techniques provided a complete understanding of the internal and external uterine structures, enabling us to perform a minimally invasive hysteroscopic metroplasty, guided by transrectal ultrasound, and therefore avoiding the need for laparotomy/laparoscopy. The outcome of treatment was considered satisfactory; menstruation ceased to be painful and, after two hysteroscopic procedures, the communicating 0.3-cm(3) hemicavity was visualized as a 3.6-cm(3) normalized uterine cavity using the same imaging techniques. The findings of this case report raise questions about the embryological origin of Robert's uterus, the suitability of current classification systems, and the role of more invasive approaches (laparoscopy/laparotomy) and surgical procedures (horn resection/endometrectomy) that do not aim to improve uterine cavity shape and volume in women with this condition. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

  4. Endoscopic ultrasound hemostasis techniques.

    PubMed

    Artifon, Everson L A; Aparicio, Dayse P S; Otoch, Jose P; Carvalho, Paulo B; Marson, Fernando P; Fernandes, Kaie; Tchekmedyian, Asadur J

    2014-04-01

    Since its development, endoscopic ultrasound (EUS) has evolved from a simple diagnostic technique to an important therapeutic tool for interventional endoscopy. EUS analysis provides real-time imaging of most major thoracic and abdominal vessels, and the possibility to use needle puncture with a curved linear array echoendoscope as a vascular intervention. In this review, we describe the endoscopic ultrasound approach to vascular therapy outside of the gastrointestinal wall.

  5. Thumb ultrasound: Technique and pathologies

    PubMed Central

    Singh, Jatinder P; Kumar, Shwetam; Kathiria, Atman V; Harjai, Rachit; Jawed, Akram; Gupta, Vikas

    2016-01-01

    Ultrasound is ideally suited for the assessment of complex anatomy and pathologies of the thumb. Focused and dynamic thumb ultrasound can provide a rapid real-time diagnosis and can be used for guided treatment in certain clinical situations. We present a simplified approach to scanning technique for thumb-related pathologies and illustrate a spectrum of common and uncommon pathologies encountered. PMID:27857468

  6. Human uses of ultrasound: ancient and modern.

    PubMed

    Wade, G

    2000-03-01

    For untold millennia certain animals have used ultrasound to probe places where light is unavailable, echo-locating bats being among the most adept. With ultrasonics, bats can quickly and safely 'see' at night in pursuing insects or flying in dark caves. Unable to hear ultrasound, humans have nevertheless made use of it. They did this anciently by taming wolves, with their keen ultrasonic hearing, for aiding in the hunt. Currently, they are doing this by developing technology to detect, generate and process ultrasound for searching in air or other gases, in water or other liquids, and in solids. The story of these technological developments is a large and fascinating mirror of human history involving the advent of such discoveries and inventions as magnetostriction, piezoelectricity, sonar, ultrasonic microscopy, etc.--the list is long. By now we are skilled in probing for underwater objects, the internal structure in materials, organs inside the human body, etc.--again the list is long. A number of different ultrasonic systems can be categorized into one of three key generic approaches: pulse-echo exploration, intensity mapping, and phase-amplitude measurement. In addition, each of these categories can be combined with the others to produce hybrid systems for which an unambiguous categorization is difficult or impossible. Challenging problems remain but solutions are being found. New principles and techniques are being discovered that will improve the use of ultrasound. Employing tomo-holographic techniques to reduce ambiguity in probing three-dimensional objects, near-field techniques to boost resolution and using limited-diffraction beams to provide image construction with ultra high frame rates are cases in point.

  7. Ultrasound Techniques for Space Applications

    NASA Technical Reports Server (NTRS)

    Rooney, James A.

    1985-01-01

    Ultrasound has proven to be a safe non-invasive technique for imaging organs and measuring cardiovascular function. It has unique advantages for application to problems with man in space including evaluation of cardiovascular function both in serial studies and during critical operations. In addition, specialized instrumentation may be capable of detecting the onset of decompression sickness during EVA activities. A spatial location and three-dimensional reconstruction system is being developed to improve the accuracy and reproducibility for serial comparative ultrasound studies of cardiovascular function. The three-dimensional method permits the acquisition of ultrasonic images from many views that can be recombined into a single reconstruction of the heart or vasculature. In addition to conventional imaging and monitoring systems, it is sometimes necessary or desirable to develop instrumentation for special purposes. One example of this type of development is the design of a pulsed-Doppler system to monitor cerebral blood flow during critical operations such as re-entry. A second example is the design of a swept-frequency ultrasound system for the detection of bubbles in the circulatory system and/or soft tissues as an early indication of the onset of decompression sickness during EVA activities. This system exploits the resonant properties of bubbles and can detect both fundamental and second harmonic emissions from the insonified region.

  8. Ultrasound Techniques for Space Applications

    NASA Technical Reports Server (NTRS)

    Rooney, James A.

    1985-01-01

    Ultrasound has proven to be a safe non-invasive technique for imaging organs and measuring cardiovascular function. It has unique advantages for application to problems with man in space including evaluation of cardiovascular function both in serial studies and during critical operations. In addition, specialized instrumentation may be capable of detecting the onset of decompression sickness during EVA activities. A spatial location and three-dimensional reconstruction system is being developed to improve the accuracy and reproducibility for serial comparative ultrasound studies of cardiovascular function. The three-dimensional method permits the acquisition of ultrasonic images from many views that can be recombined into a single reconstruction of the heart or vasculature. In addition to conventional imaging and monitoring systems, it is sometimes necessary or desirable to develop instrumentation for special purposes. One example of this type of development is the design of a pulsed-Doppler system to monitor cerebral blood flow during critical operations such as re-entry. A second example is the design of a swept-frequency ultrasound system for the detection of bubbles in the circulatory system and/or soft tissues as an early indication of the onset of decompression sickness during EVA activities. This system exploits the resonant properties of bubbles and can detect both fundamental and second harmonic emissions from the insonified region.

  9. Contrast-specific ultrasound techniques.

    PubMed

    Quaia, E

    2007-06-01

    The advent of microbubble contrast agents has determined an important evolution of ultrasound (US) technology due to the introduction of contrast-specific US techniques. This was due to the fact that neither colour or power Doppler are suitable for correct management of the signals produced by microbubble insonation, as they are limited by the heavy presence of artefacts. Microbubbles may be insonated by a characteristic frequency named resonance or fundamental frequency (f (0)) by using a high or low transmit power. If insonated by a high transmit power, microbubbles produce a wideband harmonic signal due to microbubble destruction. If insonated by a low transmit power, microbubbles produce harmonic frequencies (2f, 3f, 4f) due to their nonlinear physical behaviour. Contrast-specific US techniques have recently undergone an important technical development with the introduction of innovative algorithms able to register selectively the harmonic signals produced by microbubbles and to suppress the signal produced by stationary tissues. The different contrast-specific US techniques may be distinguished by their basic principle into pseudo-Doppler, harmonic, phase-modulation, amplitude-modulation and phase-and amplitude-modulation techniques.

  10. Integrating ultrasound into modern medical curricula.

    PubMed

    Patel, Shilpan G; Benninger, Brion; Mirjalili, S Ali

    2017-05-01

    Ultrasonography is widely practiced in many disciplines. It is becoming increasingly important to design well-structured curricula to introduce imaging to students during medical school. This review aims to analyze the literature for evidence of how ultrasonography has been incorporated into anatomy education in medical school curricula worldwide. A literature search was conducted using multiple databases with the keywords: "Ultrasound OR Ultrasonographic examination*" and "Medical student* OR Undergraduate teaching* OR Medical education*" and "Anatomy* OR Living anatomy* OR Real-time anatomy.*" This review found that ultrasound curricula vary in stage of implementation, course length, number of sessions offered to students as well as staffing and additional course components. Most courses consisted of didactic lectures supplemented with demonstration sessions and/or hands-on ultrasound scanning sessions. The stage of course implementation tended to depend on the aim of the course; introductory courses were offered earlier in a student's career. Most courses improved student confidence and exam performance, and more junior students tended to benefit more from learning anatomy with ultrasound guidance rather than learning clinical examination skills. Students tended to prefer smaller groups when learning ultrasound to get more access to using the machines themselves. Ultrasonography is an important skill, which should be taught to medical students early in their careers as it facilitates anatomical education and is clinically relevant, though further objective research required to support the use of ultrasound education as a tool to improve clinical examination skills in medical students. Clin. Anat. 30:452-460, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  11. Ultrasound elastography: principles, techniques, and clinical applications.

    PubMed

    Dewall, Ryan J

    2013-01-01

    Ultrasound elastography is an emerging set of imaging modalities used to image tissue elasticity and are often referred to as virtual palpation. These techniques have proven effective in detecting and assessing many different pathologies, because tissue mechanical changes often correlate with tissue pathological changes. This article reviews the principles of ultrasound elastography, many of the ultrasound-based techniques, and popular clinical applications. Originally, elastography was a technique that imaged tissue strain by comparing pre- and postcompression ultrasound images. However, new techniques have been developed that use different excitation methods such as external vibration or acoustic radiation force. Some techniques track transient phenomena such as shear waves to quantitatively measure tissue elasticity. Clinical use of elastography is increasing, with applications including lesion detection and classification, fibrosis staging, treatment monitoring, vascular imaging, and musculoskeletal applications.

  12. Pulse Compression Techniques for Laser Generated Ultrasound

    NASA Technical Reports Server (NTRS)

    Anastasi, R. F.; Madaras, E. I.

    1999-01-01

    Laser generated ultrasound for nondestructive evaluation has an optical power density limit due to rapid high heating that causes material damage. This damage threshold limits the generated ultrasound amplitude, which impacts nondestructive evaluation inspection capability. To increase ultrasound signal levels and improve the ultrasound signal-to-noise ratio without exceeding laser power limitations, it is possible to use pulse compression techniques. The approach illustrated here uses a 150mW laser-diode modulated with a pseudo-random sequence and signal correlation. Results demonstrate the successful generation of ultrasonic bulk waves in aluminum and graphite-epoxy composite materials using a modulated low-power laser diode and illustrate ultrasound bandwidth control.

  13. 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.

  14. Hybrid ultrasound imaging techniques (fusion imaging).

    PubMed

    Sandulescu, Daniela Larisa; Dumitrescu, Daniela; Rogoveanu, Ion; Saftoiu, Adrian

    2011-01-07

    Visualization of tumor angiogenesis can facilitate non-invasive evaluation of tumor vascular characteristics to supplement the conventional diagnostic imaging goals of depicting tumor location, size, and morphology. Hybrid imaging techniques combine anatomic [ultrasound, computed tomography (CT), and/or magnetic resonance imaging (MRI)] and molecular (single photon emission CT and positron emission tomography) imaging modalities. One example is real-time virtual sonography, which combines ultrasound (grayscale, colour Doppler, or dynamic contrast harmonic imaging) with contrast-enhanced CT/MRI. The benefits of fusion imaging include an increased diagnostic confidence, direct comparison of the lesions using different imaging modalities, more precise monitoring of interventional procedures, and reduced radiation exposure.

  15. Modern Observational Techniques for Comets

    NASA Technical Reports Server (NTRS)

    Brandt, J. C. (Editor); Greenberg, J. M. (Editor); Donn, B. (Editor); Rahe, J. (Editor)

    1981-01-01

    Techniques are discussed in the following areas: astrometry, photometry, infrared observations, radio observations, spectroscopy, imaging of coma and tail, image processing of observation. The determination of the chemical composition and physical structure of comets is highlighted.

  16. Ultrasound elastographic techniques in focal liver lesions

    PubMed Central

    Conti, Clara Benedetta; Cavalcoli, Federica; Fraquelli, Mirella; Conte, Dario; Massironi, Sara

    2016-01-01

    Elastographic techniques are new ultrasound-based imaging techniques developed to estimate tissue deformability/stiffness. Several ultrasound elastographic approaches have been developed, such as static elastography, transient elastography and acoustic radiation force imaging methods, which include point shear wave and shear wave imaging elastography. The application of these methods in clinical practice aims at estimating the mechanical tissues properties. One of the main settings for the application of these tools has been liver stiffness assessment in chronic liver disease, which has been studied mainly using transient elastography. Another field of application for these techniques is the assessment of focal lesions, detected by ultrasound in organs such as pancreas, prostate, breast, thyroid, lymph nodes. Considering the frequency and importance of the detection of focal liver lesions through routine ultrasound, some studies have also aimed to assess the role that elestography can play in studying the stiffness of different types of liver lesions, in order to predict their nature and thus offer valuable non-invasive methods for the diagnosis of liver masses. PMID:26973405

  17. Ultrasound elastographic techniques in focal liver lesions.

    PubMed

    Conti, Clara Benedetta; Cavalcoli, Federica; Fraquelli, Mirella; Conte, Dario; Massironi, Sara

    2016-03-07

    Elastographic techniques are new ultrasound-based imaging techniques developed to estimate tissue deformability/stiffness. Several ultrasound elastographic approaches have been developed, such as static elastography, transient elastography and acoustic radiation force imaging methods, which include point shear wave and shear wave imaging elastography. The application of these methods in clinical practice aims at estimating the mechanical tissues properties. One of the main settings for the application of these tools has been liver stiffness assessment in chronic liver disease, which has been studied mainly using transient elastography. Another field of application for these techniques is the assessment of focal lesions, detected by ultrasound in organs such as pancreas, prostate, breast, thyroid, lymph nodes. Considering the frequency and importance of the detection of focal liver lesions through routine ultrasound, some studies have also aimed to assess the role that elestography can play in studying the stiffness of different types of liver lesions, in order to predict their nature and thus offer valuable non-invasive methods for the diagnosis of liver masses.

  18. [Modern ultrasonographic techniques for the study of the synovial membrane in rheumatic diseases].

    PubMed

    Jeka, Sławomir; Sokólska, Elzbieta; Ignaczak, Piotr; Dura, Marta

    2010-01-01

    In recent years ultrasonography has become one of basic imaging techniques used by radiologists, orthopedists, and rheumatologists for the study of the musculoskeletal system, particularly in patients with rheumatic diseases. This position of ultrasonography is the result of rapid technical advances. Contemporary ultrasound scanners have little in common with those used when ultrasonography was introduced into medicine. Modern ultrasound scanners offer additional options like tissue harmonic imaging, power color Doppler, volumetric ultrasonography (3D/4D imaging), and contrast-enhanced ultrasonography. Moreover, image resolution during examination has significantly been improved thanks to high-resolution transducers and software for image analysis. This article discusses modern ultrasonographic techniques and their use.

  19. Modern Experimental Techniques in Turbine Engine Testing

    NASA Technical Reports Server (NTRS)

    Lepicovsky, J.; Bruckner, R. J.; Bencic, T. J.; Braunscheidel, E. P.

    1996-01-01

    The paper describes application of two modern experimental techniques, thin-film thermocouples and pressure sensitive paint, to measurement in turbine engine components. A growing trend of using computational codes in turbomachinery design and development requires experimental techniques to refocus from overall performance testing to acquisition of detailed data on flow and heat transfer physics to validate these codes for design applications. The discussed experimental techniques satisfy this shift in focus. Both techniques are nonintrusive in practical terms. The thin-film thermocouple technique improves accuracy of surface temperature and heat transfer measurements. The pressure sensitive paint technique supplies areal surface pressure data rather than discrete point values only. The paper summarizes our experience with these techniques and suggests improvements to ease the application of these techniques for future turbomachinery research and code verifications.

  20. Ultrasound and ultrasound-related techniques in endocrine diseases.

    PubMed

    Trimboli, Pierpaolo; Dietrich, Christoph F; David, Emanuele; Mastroeni, Giampiero; Ventura Spagnolo, Orazio; Sidhu, Paul S; Letizia, Claudio; Messineo, Daniela; D'Ambrosio, Ferdinando; Radzina, Maija; Cantisani, Vito

    2017-09-05

    Ultrasound examination has become essential to evaluate morphology and size of several endocrine glands and detect the presence of lesions within these organs. Nevertheless, with the recent advances of ultrasound technology, we have opportunity to correlate the echostructure of thyroid, ovary, testis, parathyroids, etc. to their function. Thus, the ultrasound systems are in-office essential instruments for many clinical specialists. Herein we presented the most updated information about the use of ultrasound in specific endocrine-related issues, such as thyroid, parathyroid, adrenal gland, and testicle.

  1. [Abdominal ultrasound course an introduction to the ultrasound technique. Physical basis. Ultrasound language].

    PubMed

    Segura-Grau, A; Sáez-Fernández, A; Rodríguez-Lorenzo, A; Díaz-Rodríguez, N

    2014-01-01

    Ultrasound is a non-invasive, accessible, and versatile diagnostic technique that uses high frequency ultrasound waves to define outline the organs of the human body, with no ionising radiation, in real time and with the capacity to visual several planes. The high diagnostic yield of the technique, together with its ease of uses plus the previously mentioned characteristics, has currently made it a routine method in daily medical practice. It is for this reason that the multidisciplinary character of this technique is being strengthened every day. To be able to perform the technique correctly requires knowledge of the physical basis of ultrasound, the method and the equipment, as well as of the human anatomy, in order to have the maximum information possible to avoid diagnostic errors due to poor interpretation or lack of information. Copyright © 2013 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España. All rights reserved.

  2. [Imaging techniques in modern trauma diagnostics].

    PubMed

    Vogl, T J; Eichler, K; Marzi, I; Wutzler, S; Zacharowski, K; Frellessen, C

    2017-08-17

    Modern trauma room management requires interdisciplinary teamwork and synchronous communication between a team of anaesthesists, surgeons and radiologists. As the length of stay in the trauma room influences morbidity and mortality of a severely injured person, optimizing time is one of the main targets. With the direct involvement of modern imaging techniques the injuries caused by trauma should be detected within a very short period of time in order to enable a priority-orientated treatment. Radiology influences structure and process quality, management and development of trauma room algorithms regarding the use of imaging techniques. For the individual case interventional therapy methods can be added. Based on current data and on the Frankfurt experience the current diagnostic concepts of trauma diagnostics are presented.

  3. [Imaging techniques in modern trauma diagnostics].

    PubMed

    Vogl, T J; Eichler, K; Marzi, I; Wutzler, S; Zacharowski, K; Frellessen, C

    2017-05-01

    Modern trauma room management requires interdisciplinary teamwork and synchronous communication between a team of anaesthesists, surgeons and radiologists. As the length of stay in the trauma room influences morbidity and mortality of a severely injured person, optimizing time is one of the main targets. With the direct involvement of modern imaging techniques the injuries caused by trauma should be detected within a very short period of time in order to enable a priority-orientated treatment. Radiology influences structure and process quality, management and development of trauma room algorithms regarding the use of imaging techniques. For the individual case interventional therapy methods can be added. Based on current data and on the Frankfurt experience the current diagnostic concepts of trauma diagnostics are presented.

  4. [Imaging techniques in modern trauma diagnostics].

    PubMed

    Vogl, T J; Eichler, K; Marzi, I; Wutzler, S; Zacharowski, K; Frellessen, C

    2017-09-21

    Modern trauma room management requires interdisciplinary teamwork and synchronous communication between a team of anaesthesists, surgeons and radiologists. As the length of stay in the trauma room influences morbidity and mortality of a severely injured person, optimizing time is one of the main targets. With the direct involvement of modern imaging techniques the injuries caused by trauma should be detected within a very short period of time in order to enable a priority-orientated treatment. Radiology influences structure and process quality, management and development of trauma room algorithms regarding the use of imaging techniques. For the individual case interventional therapy methods can be added. Based on current data and on the Frankfurt experience the current diagnostic concepts of trauma diagnostics are presented.

  5. Ultrasound Guidance as a Rescue Technique for Peripheral Intravenous Cannulation

    DTIC Science & Technology

    2006-09-14

    Leave blank) 12. REPORT DATE 14.Sep.06 13. REPORT TYPE AND DATES COVERED MAJOR REPORT 4. TITLE AND SUBTITLE 5. FUNDING NUMBERS ULTRASOUND GUIDANCE...OIOR, Oct 94 Ultrasound Guidance as a Rescue Technique for Peripheral Intravenous Cannulation Major Nancy L. Pappas, BSN, USAF, NC Captain Terese E...landmark or visual/palpation technique in patients with access difficulties such as deep, sclerotic, small, or fragile veins. Ultrasound guidance has

  6. Cache Energy Optimization Techniques For Modern Processors

    SciTech Connect

    Mittal, Sparsh

    2013-01-01

    Modern multicore processors are employing large last-level caches, for example Intel's E7-8800 processor uses 24MB L3 cache. Further, with each CMOS technology generation, leakage energy has been dramatically increasing and hence, leakage energy is expected to become a major source of energy dissipation, especially in last-level caches (LLCs). The conventional schemes of cache energy saving either aim at saving dynamic energy or are based on properties specific to first-level caches, and thus these schemes have limited utility for last-level caches. Further, several other techniques require offline profiling or per-application tuning and hence are not suitable for product systems. In this book, we present novel cache leakage energy saving schemes for single-core and multicore systems; desktop, QoS, real-time and server systems. Also, we present cache energy saving techniques for caches designed with both conventional SRAM devices and emerging non-volatile devices such as STT-RAM (spin-torque transfer RAM). We present software-controlled, hardware-assisted techniques which use dynamic cache reconfiguration to configure the cache to the most energy efficient configuration while keeping the performance loss bounded. To profile and test a large number of potential configurations, we utilize low-overhead, micro-architecture components, which can be easily integrated into modern processor chips. We adopt a system-wide approach to save energy to ensure that cache reconfiguration does not increase energy consumption of other components of the processor. We have compared our techniques with state-of-the-art techniques and have found that our techniques outperform them in terms of energy efficiency and other relevant metrics. The techniques presented in this book have important applications in improving energy-efficiency of higher-end embedded, desktop, QoS, real-time, server processors and multitasking systems. This book is intended to be a valuable guide for both newcomers

  7. Normal shoulder ultrasound: anatomy and technique.

    PubMed

    Gupta, Harun; Robinson, Philip

    2015-07-01

    Shoulder ultrasound (US) is one of the most common applications of musculoskeletal US due to the high incidence of rotator cuff disorders. It can be used effectively for the diagnosis of rotator cuff diseases, and several studies have shown very high sensitivity and specificity for rotator cuff tears comparable with that of MRI. Shoulder US has several advantages over MRI such as lower cost, comparatively easier availability, short examination duration, dynamic capability, and ability to perform guided injection at the same appointment. However, it depends on the skill of the operator and therefore requires a standardized detailed protocol to avoid errors in diagnosis. A symptomatic area-only focused examination should not be performed because it is not uncommon to have symptoms away from the actual site of pathology. Detailed understanding of what anatomy can be evaluated is required, and this article discusses the relevant anatomy covering the rotator cuff, subacromial bursa, and acromioclavicular joint. The equipment requirements and technique of examination of different anatomical structures with transducer positions and normal sonographic appearances are described. Pitfalls and artifacts associated with shoulder US are covered; understanding them is crucial to avoid misinterpretation of findings.

  8. [Tomographic ultrasound imaging (TUI)--technique and methodological study].

    PubMed

    Markov, D

    2008-01-01

    We present a new form of data image processing obtained through three-dimensional scanning named tomographic ultrasound imaging (TUI) and discuss its technique and clinical implications in obstetrics and gynecology.

  9. Tumor functional and molecular imaging utilizing ultrasound and ultrasound-mediated optical techniques.

    PubMed

    Yuan, Baohong; Rychak, Joshua

    2013-02-01

    Tumor functional and molecular imaging has significantly contributed to cancer preclinical research and clinical applications. Among typical imaging modalities, ultrasonic and optical techniques are two commonly used methods; both share several common features such as cost efficiency, absence of ionizing radiation, relatively inexpensive contrast agents, and comparable maximum-imaging depth. Ultrasonic and optical techniques are also complementary in imaging resolution, molecular sensitivity, and imaging space (vascular and extravascular). The marriage between ultrasonic and optical techniques takes advantages of both techniques. This review introduces tumor functional and molecular imaging using microbubble-based ultrasound and ultrasound-mediated optical imaging techniques.

  10. Diagnostic Emergency Ultrasound: Assessment Techniques In The Pediatric Patient.

    PubMed

    Guttman, Joshua; Nelson, Bret P

    2016-01-01

    Emergency ultrasound is performed at the point of care to answer focused clinical questions in a rapid manner. Over the last 20 years, the use of this technique has grown rapidly, and it has become a core requirement in many emergency medicine residencies and in some pediatric emergency medicine fellowships. The use of emergency ultrasound in the pediatric setting is increasing due to the lack of ionizing radiation with these studies, as compared to computed tomography. Utilizing diagnostic ultrasound in the emergency department can allow clinicians to arrive at a diagnosis at the bedside rather than sending the patient out of the department for another study. This issue focuses on common indications for diagnostic ultrasound, as found in the pediatric literature or extrapolated from adult literature where pediatric evidence is scarce. Limitations, current trends, controversies, and future directions of diagnostic ultrasound in the emergency department are also discussed.

  11. Technique as a Consideration in Modern Dance Injuries.

    ERIC Educational Resources Information Center

    Solomon, Ruth L.; Micheli, Lyle J.

    1986-01-01

    The many different techniques of modern dance each make unique demands on the dancer's body. A study of 164 modern dancers compared injury sites and frequency with the dance technique. Results indicate technique is a factor in injuries. (Author/MT)

  12. Technique as a Consideration in Modern Dance Injuries.

    ERIC Educational Resources Information Center

    Solomon, Ruth L.; Micheli, Lyle J.

    1986-01-01

    The many different techniques of modern dance each make unique demands on the dancer's body. A study of 164 modern dancers compared injury sites and frequency with the dance technique. Results indicate technique is a factor in injuries. (Author/MT)

  13. Comparison of modern techniques for saliva screening.

    PubMed

    Myers, Jarrah R; Adkins, William K

    2008-07-01

    Saliva stains present a unique challenge in the forensic setting, often challenging the analyst to weigh the value of presumptive indication of the fluid versus the potential for DNA analysis to yield identification information. There are many situations in which determining the presence of a body fluid is probative and further corroborates DNA evidence. That said, even a minute portion of sample consumed by a screening test could mean the difference between a full, partial, or null profile obtained through DNA analysis. The basis of presumptive testing or screening of saliva has historically been based on the presence of amylase, a component found in relatively high concentrations in human saliva versus other body fluids and substances. Though the current available methods for the screening of saliva in a forensic application have grown in number, the popularity of these methods seemingly has not. This study attempts to identify a specific and sensitive saliva screening test by comparing three modern techniques--the recently released SALIgAE, Phadebas, and starch-iodine mini-centrifuge test--on the basis of sensitivity, specificity, mixtures, and simulated casework samples while also considering sample consumption. The Phadebas method for presumptive saliva testing detected dilutions of neat saliva down to 1:200 versus considerably less sensitive results with SALIgAE and the starch-iodine mini-centrifuge test. Utilizing a screening test with a high degree of sensitivity, such as Phadebas, allows an analyst to gain a maximum amount of information in the form of body fluid indication and DNA results because of the consumption of a small portion of sample.

  14. Ultrasound-Guided Needle Technique Accuracy

    PubMed Central

    Johnson, Angela N.; Peiffer, Jeffery S.; Halmann, Nahi; Delaney, Luke; Owen, Cindy A.; Hersh, Jeff

    2017-01-01

    Background and Objectives Ultrasound-guided regional anesthesia facilitates an approach to sensitive targets such as nerve clusters without contact or inadvertent puncture. We compared accuracy of needle placement with a novel passive magnetic ultrasound needle guidance technology (NGT) versus conventional ultrasound (CU) with echogenic needles. Methods Sixteen anesthesiologists and 19 residents performed a series of 16 needle insertion tasks each, 8 using NGT (n = 280) and 8 using CU (n = 280), in high-fidelity porcine phantoms. Tasks were stratified based on aiming to contact (target-contact) or place in close proximity with (target-proximity) targets, needle gauge (no. 18/no. 22), and in-plane (IP) or out-of-plane (OOP) approach. Distance to the target, task completion by aim, number of passes, and number of tasks completed on the first pass were reported. Results Needle guidance technology significantly improved distance, task completion, number of passes, and completion on the first pass compared with CU for both IP and OOP approaches (P ≤ 0.001). Average NGT distance to target was lower by 57.1% overall (n = 560, 1.5 ± 2.4 vs 3.5 ± 3.7 mm), 38.5% IP (n = 140, 1.6 ± 2.6 vs 2.6 ± 2.8 mm), and 68.2% OOP (n = 140, 1.4 ± 2.2 vs 4.4 ± 4.3 mm) (all P ≤ 0.01). Subgroup analyses revealed accuracy gains were largest among target-proximity tasks performed by residents and for OOP approaches. Needle guidance technology improved first-pass completion from 214 (76.4%) per 280 to 249 (88.9%) per 280, a significant improvement of 16.4% (P = 0.001). Conclusions Passive magnetic NGT can improve accuracy of needle procedures, particularly among OOP procedures requiring close approach to sensitive targets, such as nerve blocks in anesthesiology practice. PMID:28079754

  15. Ultrasound Elastography: Review of Techniques and Clinical Applications

    PubMed Central

    Sigrist, Rosa M.S.; Liau, Joy; Kaffas, Ahmed El; Chammas, Maria Cristina; Willmann, Juergen K.

    2017-01-01

    Elastography-based imaging techniques have received substantial attention in recent years for non-invasive assessment of tissue mechanical properties. These techniques take advantage of changed soft tissue elasticity in various pathologies to yield qualitative and quantitative information that can be used for diagnostic purposes. Measurements are acquired in specialized imaging modes that can detect tissue stiffness in response to an applied mechanical force (compression or shear wave). Ultrasound-based methods are of particular interest due to its many inherent advantages, such as wide availability including at the bedside and relatively low cost. Several ultrasound elastography techniques using different excitation methods have been developed. In general, these can be classified into strain imaging methods that use internal or external compression stimuli, and shear wave imaging that use ultrasound-generated traveling shear wave stimuli. While ultrasound elastography has shown promising results for non-invasive assessment of liver fibrosis, new applications in breast, thyroid, prostate, kidney and lymph node imaging are emerging. Here, we review the basic principles, foundation physics, and limitations of ultrasound elastography and summarize its current clinical use and ongoing developments in various clinical applications. PMID:28435467

  16. Techniques for Field Application of Lingual Ultrasound Imaging

    ERIC Educational Resources Information Center

    Gick, Bryan; Bird, Sonya; Wilson, Ian

    2005-01-01

    Techniques are discussed for using ultrasound for lingual imaging in field-related applications. The greatest challenges we have faced distinguishing the field setting from the laboratory setting are the lack of controlled head/transducer movement, and the related issue of tissue compression. Two experiments are reported. First, a pilot study…

  17. Techniques for Field Application of Lingual Ultrasound Imaging

    ERIC Educational Resources Information Center

    Gick, Bryan; Bird, Sonya; Wilson, Ian

    2005-01-01

    Techniques are discussed for using ultrasound for lingual imaging in field-related applications. The greatest challenges we have faced distinguishing the field setting from the laboratory setting are the lack of controlled head/transducer movement, and the related issue of tissue compression. Two experiments are reported. First, a pilot study…

  18. Improvement of ultrasound speckle image velocimetry using image enhancement techniques.

    PubMed

    Yeom, Eunseop; Nam, Kweon-Ho; Paeng, Dong-Guk; Lee, Sang Joon

    2014-01-01

    Ultrasound-based techniques have been developed and widely used in noninvasive measurement of blood velocity. Speckle image velocimetry (SIV), which applies a cross-correlation algorithm to consecutive B-mode images of blood flow has often been employed owing to its better spatial resolution compared with conventional Doppler-based measurement techniques. The SIV technique utilizes speckles backscattered from red blood cell (RBC) aggregates as flow tracers. Hence, the intensity and size of such speckles are highly dependent on hemodynamic conditions. The grayscale intensity of speckle images varies along the radial direction of blood vessels because of the shear rate dependence of RBC aggregation. This inhomogeneous distribution of echo speckles decreases the signal-to-noise ratio (SNR) of a cross-correlation analysis and produces spurious results. In the present study, image-enhancement techniques such as contrast-limited adaptive histogram equalization (CLAHE), min/max technique, and subtraction of background image (SB) method were applied to speckle images to achieve a more accurate SIV measurement. A mechanical sector ultrasound scanner was used to obtain ultrasound speckle images from rat blood under steady and pulsatile flows. The effects of the image-enhancement techniques on SIV analysis were evaluated by comparing image intensities, velocities, and cross-correlation maps. The velocity profiles and wall shear rate (WSR) obtained from RBC suspension images were compared with the analytical solution for validation. In addition, the image-enhancement techniques were applied to in vivo measurement of blood flow in human vein. The experimental results of both in vitro and in vivo SIV measurements show that the intensity gradient in heterogeneous speckles has substantial influence on the cross-correlation analysis. The image-enhancement techniques used in this study can minimize errors encountered in ultrasound SIV measurement in which RBCs are used as flow

  19. Modern Reservoir Sedimentation Management Techniques with Examples

    NASA Astrophysics Data System (ADS)

    Annandale, G. W.

    2014-12-01

    Implementation of reservoir sedimentation management approaches results in a win-win scenario, it assists in enhancing the environment by preserving river function downstream of dams while concurrently providing opportunities to sustainably manage water resource infrastructure. This paper summarizes the most often used reservoir sedimentation management techniques with examples of where they have been implemented. Three categories can be used to classify these technologies, i.e. catchment management, sediment routing and sediment removal. The objective of catchment management techniques is to minimize the amount of sediment that may discharge into a reservoir, thereby reducing the loss of storage space due to sedimentation. Reservoir routing is a set of techniques that aim at minimizing the amount of sediment that may deposit in a reservoir, thereby maximizing the amount of sediment that may be passed downstream. The third group consists of techniques that may be used to remove previously deposited sediment from reservoirs. The selection of reservoir sedimentation management approaches is site specific and depends on various factors, including dam height, reservoir volume, reservoir length, valley shape, valley slope, sediment type and hydrology. Description of the different reservoir sedimentation management techniques that are used in practice will be accompanied by case studies, including video, illustrating criteria that may be used to determine the potential success of implementing the techniques.

  20. Synthesis of Hydroxyapatite through Ultrasound and Calcination Techniques

    NASA Astrophysics Data System (ADS)

    Akindoyo, John O.; Beg, M. D. H.; Ghazali, Suriati; Akindoyo, Edward O.; Jeyaratnam, Nitthiyah

    2017-05-01

    There is a growing demand for hydroxyapatite (HA) especially in medical applications, production of HA which is totally green is however a challenge. In this research, HA was produced from biowaste through ultrasound followed by calcination techniques. Pre-treatment of the biowaste was effectively achieved through the help of ultrasound. After calcination at 950°C, the obtained HA was characterized through Thermogravimetric (TGA) analysis, X-ray diffraction analysis (XRD) and Fourier transform infrared spectroscopy (FTIR). Spectrum of the produced HA was compared with standard HA index. The spectrum is in agreement with the standard HA as confirmed through FTIR, XRD and TGA result. Furthermore, morphological study of the HA through Field emission scanning electron microscope (FESEM) shows almost uniform spherical shape for the HA as expected. Based on the results obtained herein, combining ultrasound with calcination can help to produce pure HA with potential medical applications without the use of any organic solvent.

  1. Modern Ultrasound Imaging: AN Exciting Window Into the Sub-Surface World

    NASA Astrophysics Data System (ADS)

    Simonetti, F.

    2009-03-01

    Progress in solid state electronics and micromachining has led to the rapid development of ultrasound array technology. It is now possible to measure spatial maps of ultrasonic fields almost instantaneously, with high sensitivity and under various insonification conditions. The technology has become central to imaging in combination with beamforming techniques for applications in medical diagnostics and now in NDE for defect characterization. However, the resolution of current beamforming technology is limited. Indeed, it is not possible to observe the sub-wavelength structure of an object due to diffraction as demonstrated by Lord Rayleigh more than a century ago. This paper introduces the notion that ultrasonic measurements encode more information about the object's structure than beamforming can extract. The key to unlock this information is provided by the knowledge of the scattering mechanism that has caused the encoding in the first instance. This leads to a modern imaging strategy that goes beyond beamforming, can achieve subwavelength resolution and shares some of the underpinning physics with near field microscopy—known to break the Rayleigh criterion. These arguments are supported by experimental images showing unprecedented subwavelength resolution and tomographic reconstructions of a complex 3-D breast phantom that exhibit striking similarities with X-ray CT.

  2. Modern Language Classroom Techniques. A Handbook.

    ERIC Educational Resources Information Center

    Allen, Edward David; Valette, Rebecca M.

    The aim of this handbook is to show the teacher ways of implementing and supplementing existing materials. The suggested teaching procedures may be used in classes of varying sizes and levels, and with any method. Although the emphasis is on teacher-made materials, many of the techniques suggested may be implemented with commercial programs,…

  3. Wrist ultrasound examination – scanning technique and ultrasound anatomy. Part 1: Dorsal wrist

    PubMed Central

    Łasecki, Mateusz; Zaleska-Dorobisz, Urszula

    2015-01-01

    Ultrasound imaging of the musculoskeletal system is superior to other imaging methods in many aspects, such as multidimensional character of imaging, possibility of dynamic evaluation and precise assessment of soft tissues. Moreover, it is a safe and relatively inexpensive method, broadly available and well-tolerated by patients. A correctly conducted ultrasound examination of the wrist delivers detailed information concerning the condition of tendons, muscles, ligaments, nerves and vessels. However, the knowledge of anatomy is crucial to establish a correct ultrasound diagnosis, also in wrist assessment. An ultrasound examination of the wrist is one of the most common US examinations conducted in patients with rheumatological diseases. Ultrasonographic signs depend on the advancement of the disease. The examination is equally frequently conducted in patients with pain or swelling of the wrist due to non-rheumatological causes. The aim of this publication was to present ultrasound images and anatomic schemes corresponding to them. The correct scanning technique of the dorsal part of the wrist was discussed and some practical tips, thanks to which highly diagnostic images can be obtained, were presented. The following anatomical structures should be visualized in an ultrasound examination of the dorsal wrist: distal radio-ulnar joint, radiocarpal joint, midcarpal joint, carpometacarpal joints, dorsal radiocarpal ligament, compartments of extensor tendons, radial artery, cephalic vein, two small branches of the radial nerve: superficial and deep, as well as certain midcarpal ligaments, particularly the scapholunate ligament and lunotriquetral ligament. The paper was distinguished in 2014 as the “poster of the month” (poster number C-1896) during the poster session of the European Congress of Radiology in Vienna. PMID:26675810

  4. 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

  5. Treatment of petroleum-contaminated water resources: modern techniques

    NASA Astrophysics Data System (ADS)

    Pogharnitskaya, O. V.; Konovalov, V. V.; Dmitrieva, N. V.; Belozerova, D. S.; Strelnikova, A. B.

    2016-09-01

    The article deals with the issue of petroleum-contaminated water resources. The authors have analyzed the dynamics of oil spills, including the world's largest ones, and claimed the issue to be global. The modern methods of mitigating oil spill effects have been studied, as well as the modern techniques of water resource treatment. The particular attention is paid to peat sorbent production, which is considered a promising trend of petroleum- contaminated water treatment.

  6. Internal Jugular Vein Cannulation: An Ultrasound-Guided Technique Versus a Landmark-Guided Technique

    PubMed Central

    Turker, Gurkan; Kaya, Fatma Nur; Gurbet, Alp; Aksu, Hale; Erdogan, Cuneyt; Atlas, Ahmet

    2009-01-01

    OBJECTIVES To compare the landmark-guided technique versus the ultrasound-guided technique for internal jugular vein cannulation in spontaneously breathing patients. METHODS A total of 380 patients who required internal jugular vein cannulation were randomly assigned to receive internal jugular vein cannulation using either the landmark- or ultrasound-guided technique in Bursa, Uludag University Faculty of Medicine, between April and November, 2008. Failed catheter placement, risk of complications from placement, risk of failure on first attempt at placement, number of attempts until successful catheterization, time to successful catheterization and the demographics of each patient were recorded. RESULTS The overall complication rate was higher in the landmark group than in the ultrasound-guided group (p < 0.01). Carotid puncture rate and hematoma were more frequent in the landmark group than in the ultrasound-guided group (p < 0.05). The number of attempts for successful placement was significantly higher in the landmark group than in the ultrasound-guided group, which was accompanied by a significantly increased access time observed in the landmark group (p < 0.05 and p < 0.01, respectively). Although there were a higher number of attempts, longer access time, and a more frequent complication rate in the landmark group, the success rate was found to be comparable between the two groups. CONCLUSION The findings of this study indicate that internal jugular vein catheterization guided by real-time ultrasound results in a lower access time and a lower rate of immediate complications. PMID:19841706

  7. Automatic Cataract Hardness Classification Ex Vivo by Ultrasound Techniques.

    PubMed

    Caixinha, Miguel; Santos, Mário; Santos, Jaime

    2016-04-01

    To demonstrate the feasibility of a new methodology for cataract hardness characterization and automatic classification using ultrasound techniques, different cataract degrees were induced in 210 porcine lenses. A 25-MHz ultrasound transducer was used to obtain acoustical parameters (velocity and attenuation) and backscattering signals. B-Scan and parametric Nakagami images were constructed. Ninety-seven parameters were extracted and subjected to a Principal Component Analysis. Bayes, K-Nearest-Neighbours, Fisher Linear Discriminant and Support Vector Machine (SVM) classifiers were used to automatically classify the different cataract severities. Statistically significant increases with cataract formation were found for velocity, attenuation, mean brightness intensity of the B-Scan images and mean Nakagami m parameter (p < 0.01). The four classifiers showed a good performance for healthy versus cataractous lenses (F-measure ≥ 92.68%), while for initial versus severe cataracts the SVM classifier showed the higher performance (90.62%). The results showed that ultrasound techniques can be used for non-invasive cataract hardness characterization and automatic classification.

  8. A novel fast full inversion based breast ultrasound elastography technique.

    PubMed

    Karimi, Hirad; Fenster, Aaron; Samani, Abbas

    2013-04-07

    Cancer detection and classification have been the focus of many imaging and therapeutic research studies. Elastography is a non-invasive technique to visualize suspicious soft tissue areas where tissue stiffness is used as image contrast mechanism. In this study, a breast ultrasound elastography system including software and hardware is proposed. Unlike current elastography systems that image the tissue strain and present it as an approximation to relative tissue stiffness, this system is capable of imaging the breast absolute Young's modulus in fast fashion. To improve the quality of elastography images, a novel system consisting of two load cells has been attached to the ultrasound probe. The load cells measure the breast surface forces to be used for calculating the tissue stress distribution throughout the breast. To facilitate fast imaging, this stress calculation is conducted by an accelerated finite element method. Acquired tissue displacements and surface force data are used as input to the proposed Young's modulus reconstruction technique. Numerical and tissue mimicking phantom studies were conducted for validating the proposed system. These studies indicated that fast imaging of breast tissue absolute Young's modulus using the proposed ultrasound elastography system is feasible. The tissue mimicking phantom study indicated that the system is capable of providing reliable absolute Young's modulus values for both normal tissue and tumour as the maximum Young's modulus reconstruction error was less than 6%. This demonstrates that the proposed system has a good potential to be used for clinical breast cancer assessment.

  9. A novel fast full inversion based breast ultrasound elastography technique

    NASA Astrophysics Data System (ADS)

    Karimi, Hirad; Fenster, Aaron; Samani, Abbas

    2013-04-01

    Cancer detection and classification have been the focus of many imaging and therapeutic research studies. Elastography is a non-invasive technique to visualize suspicious soft tissue areas where tissue stiffness is used as image contrast mechanism. In this study, a breast ultrasound elastography system including software and hardware is proposed. Unlike current elastography systems that image the tissue strain and present it as an approximation to relative tissue stiffness, this system is capable of imaging the breast absolute Young’s modulus in fast fashion. To improve the quality of elastography images, a novel system consisting of two load cells has been attached to the ultrasound probe. The load cells measure the breast surface forces to be used for calculating the tissue stress distribution throughout the breast. To facilitate fast imaging, this stress calculation is conducted by an accelerated finite element method. Acquired tissue displacements and surface force data are used as input to the proposed Young’s modulus reconstruction technique. Numerical and tissue mimicking phantom studies were conducted for validating the proposed system. These studies indicated that fast imaging of breast tissue absolute Young’s modulus using the proposed ultrasound elastography system is feasible. The tissue mimicking phantom study indicated that the system is capable of providing reliable absolute Young’s modulus values for both normal tissue and tumour as the maximum Young’s modulus reconstruction error was less than 6%. This demonstrates that the proposed system has a good potential to be used for clinical breast cancer assessment.

  10. High intensity focused ultrasound surgery (HIFU) of the brain: A historical perspective, with modern applications

    PubMed Central

    Jagannathan, Jay; Sanghvi, Narendra K; Crum, Lawrence A; Yen, Chun-Po; Medel, Ricky; Dumont, Aaron S; Sheehan, Jason P; Steiner, Ladislau; Jolesz, Ferenc; Kassell, Neal F

    2014-01-01

    The field of MRI-guided high intensity focused ultrasound surgery (MRgFUS) is a rapidly evolving one with many potential applications in neurosurgery. This is the first of three articles on MRgFUS, this paper focuses on the historical development of the technology and it's potential applications to modern neurosurgery. The evolution of MRgFUS has occurred in parallel with modern neurological surgery and the two seemingly distinct disciplines share many of the same pioneering figures. Early studies on focused ultrasound treatment in the 1940's and 1950's demonstrated the ability to perform precise lesioning in the human brain, with a favorable risk-benefit profile. However, the need for a craniotomy, as well as lack of sophisticated imaging technology resulted in limited growth of HIFU for neurosurgery. More recently, technological advances, have permitted the combination of HIFU along with MRI guidance to provide an opportunity to effectively treat a variety of CNS disorders. Although challenges remain, HIFU-mediated neurosurgery may offer the ability to target and treat CNS conditions that were previously extremely difficult to perform. The remaining two articles in this series will focus on the physical principles of modern MRgFUS as well as current and future avenues for investigation. PMID:19190451

  11. Modern reconstructive techniques for abdominal wall defects after oncologic resection.

    PubMed

    Khansa, Ibrahim; Janis, Jeffrey E

    2015-04-01

    Resection of abdominal wall tumors often leaves patients with debilitating soft tissue defects. Modern reconstructive techniques can be used to restore abdominal wall integrity. In this article, we present an overview of preoperative patient evaluation, analysis of the defect, surgical planning, and the spectrum of available surgical techniques, ranging from simple to complex. The established clinical evidence in the field of abdominal wall reconstruction is summarized and a case example is provided.

  12. Modern techniques for condition monitoring of railway vehicle dynamics

    NASA Astrophysics Data System (ADS)

    Ngigi, R. W.; Pislaru, C.; Ball, A.; Gu, F.

    2012-05-01

    A modern railway system relies on sophisticated monitoring systems for maintenance and renewal activities. Some of the existing conditions monitoring techniques perform fault detection using advanced filtering, system identification and signal analysis methods. These theoretical approaches do not require complex mathematical models of the system and can overcome potential difficulties associated with nonlinearities and parameter variations in the system. Practical applications of condition monitoring tools use sensors which are mounted either on the track or rolling stock. For instance, monitoring wheelset dynamics could be done through the use of track-mounted sensors, while vehicle-based sensors are preferred for monitoring the train infrastructure. This paper attempts to collate and critically appraise the modern techniques used for condition monitoring of railway vehicle dynamics by analysing the advantages and shortcomings of these methods.

  13. Cardiac Limited Ultrasound Examination Techniques to Augment the Bedside Cardiac Physical Examination.

    PubMed

    Kimura, Bruce J; Shaw, David J; Amundson, Stan A; Phan, James N; Blanchard, Daniel G; DeMaria, Anthony N

    2015-09-01

    The current practice of physical diagnosis is dependent on physician skills and biases, inductive reasoning, and time efficiency. Although the clinical utility of echocardiography is well known, few data exist on how to integrate 2-dimensional screening "quick-look" ultrasound applications into a novel, modernized cardiac physical examination. We discuss the evidence basis behind ultrasound "signs" pertinent to the cardiovascular system and elemental in synthesis of bedside diagnoses and propose the application of a brief cardiac limited ultrasound examination based on these signs. An ultrasound-augmented cardiac physical examination can be taught in traditional medical education and has the potential to improve bedside diagnosis and patient care.

  14. Noninvasive skin tightening: focus on new ultrasound techniques.

    PubMed

    Fabi, Sabrina Guillen

    2015-01-01

    Microfocused ultrasound (MFU) has been recently developed to meet the ever-growing public demand for achieving significant, noninvasive skin lifting and tightening. MFU can be focused on subcutaneous tissue where the temperature briefly reaches greater than 60°C, producing small (<1 mm(3)) thermal coagulation points to a depth of up to 5 mm within the mid-to-deep reticular layer of the dermis and subdermis. The intervening papillary dermal and epidermal layers of skin remain unaffected. The application of heat at these discrete thermal coagulation points causes collagen fibers in the facial planes such as the superficial musculoaponeurotic system and platysma, as well as the deep reticular dermis, to become denatured, contracting and stimulating de novo collagen. A commercially available device combines MFU with high-resolution ultrasound imaging (MFU-V), which enables visualization of tissue planes to a depth of 8 mm and allows the user to see where the MFU energy will be applied (Ultherapy(®); Ulthera Inc., Mesa, AZ, USA). Using different transducers, MFU-V treatment can be customized to meet the unique physical characteristics of each patient by adjusting energy and focal depth of the emitted ultrasound. By targeting the facial superficial musculoaponeurotic system, noninvasive tightening and lifting of sagging facial and neck skin and improvements in the appearance of wrinkles can be achieved. MFU-V can also improve lines and wrinkles of the décolleté. Treatment protocols for the use of MFU-V continue to be refined, and its use in combination with other rejuvenation techniques has been demonstrated. Brief discomfort that often occurs during treatment can be minimized with oral nonsteroidal anti-inflammatory drugs. Other treatment-related adverse events include transient erythema, edema, and occasional bruising. MFU-V is best suited for patients with mild-to-moderate skin and soft tissue laxity. For older patients with severe skin laxity and marked platysmal

  15. Noninvasive skin tightening: focus on new ultrasound techniques

    PubMed Central

    Fabi, Sabrina Guillen

    2015-01-01

    Microfocused ultrasound (MFU) has been recently developed to meet the ever-growing public demand for achieving significant, noninvasive skin lifting and tightening. MFU can be focused on subcutaneous tissue where the temperature briefly reaches greater than 60°C, producing small (<1 mm3) thermal coagulation points to a depth of up to 5 mm within the mid-to-deep reticular layer of the dermis and subdermis. The intervening papillary dermal and epidermal layers of skin remain unaffected. The application of heat at these discrete thermal coagulation points causes collagen fibers in the facial planes such as the superficial musculoaponeurotic system and platysma, as well as the deep reticular dermis, to become denatured, contracting and stimulating de novo collagen. A commercially available device combines MFU with high-resolution ultrasound imaging (MFU-V), which enables visualization of tissue planes to a depth of 8 mm and allows the user to see where the MFU energy will be applied (Ultherapy®; Ulthera Inc., Mesa, AZ, USA). Using different transducers, MFU-V treatment can be customized to meet the unique physical characteristics of each patient by adjusting energy and focal depth of the emitted ultrasound. By targeting the facial superficial musculoaponeurotic system, noninvasive tightening and lifting of sagging facial and neck skin and improvements in the appearance of wrinkles can be achieved. MFU-V can also improve lines and wrinkles of the décolleté. Treatment protocols for the use of MFU-V continue to be refined, and its use in combination with other rejuvenation techniques has been demonstrated. Brief discomfort that often occurs during treatment can be minimized with oral nonsteroidal anti-inflammatory drugs. Other treatment-related adverse events include transient erythema, edema, and occasional bruising. MFU-V is best suited for patients with mild-to-moderate skin and soft tissue laxity. For older patients with severe skin laxity and marked platysmal

  16. Implementation of a burn scar assessment system by ultrasound techniques.

    PubMed

    Du, Yi-Chun; Lin, Chih-Ming; Chen, Yung-Fu; Chen, Chung-Lin; Chen, Tainsong

    2006-01-01

    Tissue injury and its ensuing healing process cause scar formation. In addition to physical disability, the subsequent disfigurements from burns often bring negative psychological impacts on the survivors. Scar hypertrophy and contracture limit the joint motion and body function of the patient. With fast development of the current available technologies regarding the scar therapies, not only the process of wound healing has to be focused, but also the cosmetic and functional outcomes need to be emphasized. Therefore, proper evaluation and assessment of the healing process to nil scar status is highly recommended. However, the currently employed tools for scar evaluation are mostly subjective. For example, Vancouver General Hospital (VGH) scar index uses color, pigmentation, vascularity, pliability, and depth of the scar as dependent variables for scar evaluation. These parameters only estimate the superficial surface of the scar, but they can not evaluate the deeper tissue within dermis. Ultrasound is a safe, inexpensive, and multifunctional technique for probing tissue characteristics. In addition, its resolution is not inferior to other measurement techniques. Although 3D-ultrasound is available in clinical application, it's still not widely used in scar evaluation because of its high cost. In this study, we proposed a system for scar assessment using B-mode ultrasonic technique. By utilizing the reconstruction methods to search the scar border, many characteristic parameters, including depth, area and volume, can be estimated. The proposed method is useful in assisting the clinician to evaluate the treatment effect and to plan further therapeutic strategy more objectively. In this report, the quantitative assessment system was used to evaluate the scar of a seriously burned patient. In order to verify the reliability of systematic reconstruction method, we constructed a phantom to imitate the scar tissue. The results show that it can achieve more than 90% in

  17. Rhytidectomy assisted with ultrasound techniques: the ultra-lipo-lift technique.

    PubMed

    Navarro-Viana, F

    2001-01-01

    Ultrasound-assisted liposuction has been practiced in Europe and South America for more than 10 years. This method was clinically introduced in 1989 for removal of fat by Dr. Zocchi, who developed the concept of applying ultrasound energy to adipose tissue [13,14]. Since 1992, we have been using ultrasound lipoplasty, first in body remodeling, then in face and neck surgery, after establishing working and safety rules in a study of 300 patients. In the beginning we were only looking to eliminate deposits of fat in oval faces with acne-scars, subdermal fibrosis, and thick skin, as these types of cases are not good candidates for rithidectomy. We found good skin retraction when we adjusted the superficial movements of the canula and had adequate machine power to avoid complications beneath the skin. Afterwards, we can break and release the adhesion zones of scarring and fibrosis, consequences of subdermic infiltrations or thread implants. Now we report our technique of rithidectomy assisted with ultrasound, which we have called ultra-lipo-lift (ULL). During the two last years we used this technique on 67 patients (48 females and 19 males) with good results and very few complications.

  18. Modern acoustic emission technique and its application in aviation industry.

    PubMed

    Geng, Rongsheng

    2006-12-22

    This paper proposes the concept of modern acoustic emission (MAE) technique and describes its application in aviation industry. Modern AE is characterized by the combination of AE parameter and waveform analysis based on the understanding of AE source mechanism, the property of sound wave propagation and the interaction between sound wave and the medium in which the sound wave is propagating. Another feature of MAE is characterized by the application of so-called fully digital AE apparatus with low noise, high speed of data transmission and accurate AE source locating capability. MAE is merely an imagination without the realization of the advanced fully digital AE instrument. The application of MAE in monitoring the conditions of aircraft structures during a fatigue test was taken as an example for showing the important role played by AE. Roles of AE in the evaluation of (environment-related) corrosion damage of aircraft were also presented.

  19. Basics, principles, techniques and modern methods in paediatric ultrasonography.

    PubMed

    Riccabona, Michael

    2014-09-01

    Ultrasonography (US) is the mainstay of paediatric Radiology. This review aims at revisiting basic US principles, to list specific needs throughout childhood, and to discuss the application of new and modern US methods. The various sections elude to basic US physics, technical requisites and tips for handling, diagnostically valuable applications of modern techniques, and how to properly address hazards, risks and limitations. In conclusion, US holds vast potential throughout childhood in almost all body regions and many childhood specific queries - helping to reduce the need for or to optimize more invasive or irradiating imaging. Make the most of US and offerings a dedicated paediatric US service throughout the day, the week and the year thus is and will stay a major task of Paediatric Radiology.

  20. 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 ...

  1. Endoscopic ultrasound-assisted gastrointestinal hemostasis: an evolving technique

    PubMed Central

    Jain, Deepanshu; Thosani, Nirav; Singhal, Shashideep

    2016-01-01

    Gastrointestinal bleeding can range from grossly visible blood in stool or vomitus to microscopic bleed. However, any kind of bleeding can lead to potential life-threatening consequences. A small proportion of patients with gastrointestinal bleeding remain refractory to initial endoscopic hemostasis. While some are successfully managed by repeat endoscopic intervention, a few fail to respond or are not amenable to endoscopic hemostasis. As of now, the next level of intervention is passed on to either surgeons or interventional radiologists. There is new evidence suggesting the increased utility of endoscopic ultrasound (EUS) in diagnosis and treatment of culprit vascular lesions across the gut. In addition, EUS-assisted technique has also been used in the primary prevention of bleeding from gastroesophageal varices. In this review article, we have summarized case series and reports describing the use of EUS-assisted hemostasis. Indications, techniques, complications and success rates reported are discussed. While most of the authors describe their experience with primary and secondary treatment of gastric varices, treatment of other gastrointestinal lesions with EUS assisted hemostatic techniques is also discussed. PMID:27366229

  2. Advanced endoscopic ultrasound management techniques for preneoplastic pancreatic cystic lesions

    PubMed Central

    Arshad, Hafiz Muhammad Sharjeel; Bharmal, Sheila; Duman, Deniz Guney; Liangpunsakul, Suthat; Turner, Brian G

    2017-01-01

    Pancreatic cystic lesions can be benign, premalignant or malignant. The recent increase in detection and tremendous clinical variability of pancreatic cysts has presented a significant therapeutic challenge to physicians. Mucinous cystic neoplasms are of particular interest given their known malignant potential. This review article provides a brief but comprehensive review of premalignant pancreatic cystic lesions with advanced endoscopic ultrasound (EUS) management approaches. A comprehensive literature search was performed using PubMed, Cochrane, OVID and EMBASE databases. Preneoplastic pancreatic cystic lesions include mucinous cystadenoma and intraductal papillary mucinous neoplasm. The 2012 International Sendai Guidelines guide physicians in their management of pancreatic cystic lesions. Some of the advanced EUS management techniques include ethanol ablation, chemotherapeutic (paclitaxel) ablation, radiofrequency ablation and cryotherapy. In future, EUS-guided injections of drug-eluting beads and neodymium:yttrium aluminum agent laser ablation is predicted to be an integral part of EUS-guided management techniques. In summary, International Sendai Consensus Guidelines should be used to make a decision regarding management of pancreatic cystic lesions. Advanced EUS techniques are proving extremely beneficial in management, especially in those patients who are at high surgical risk. PMID:27574295

  3. Osteotomy in direct sinus lift. A comparative study of the rotary technique and ultrasound.

    PubMed

    Peñarrocha-Diago, María; Peñarrocha-Diago, Miguel; Sanchez-Recio, Cristina; Peñarrocha-Oltra, David; Romero-Millán, Javier

    2012-05-01

    The present study investigates sinus membrane rupture in direct maxillary sinus lift with the rotary technique and with ultrasound, examining the survival of implants placed after sinus augmentation, and analyzing the bone gain obtained after the operation and 12 months after placement of the prosthetic restoration. A retrospective study was made of 45 patients requiring maxillary sinus lift or augmentation for implant-prosthetic rehabilitation. Use was made of the handpiece and ostectomy drills for the rotary technique, and of specific tips for ultrasound. The implant success criteria were based on those developed by Buser. The bone gain obtained as a result of sinus lift was calculated from the postoperative panoramic X-rays. A total of 57 direct elevations of the maxillary sinus were carried out: 32 with the rotary technique and 25 with ultrasound. Perforations of Schneider's membrane with the rotary technique and ultrasound occurred in 7% and 1.7% of the cases, respectively, with membrane integrity being preserved in 91.2%. Of the 100 implants placed, 5 failed after one year of follow-up in the rotary technique group, while one implant failed in the ultrasound group. The rotary technique in turn afforded a bone gain of 5.9 mm, versus 6.7 mm with ultrasound. Perforations of the membrane sinusal in direct lift were more frequent with the rotary technique (7%) than with ultrasound (1.7%). Implant survival and bone gain were both greater when ultrasound was used.

  4. Modern approach to an old technique: Narrative revision of techniques used to locate the epidural space.

    PubMed

    Brogly, N; Guasch Arévalo, E; Kollmann Camaiora, A; Alsina Marcos, E; García García, C; Gilsanz Rodríguez, F

    2017-03-16

    Since the first description of the epidural technique during the 1920s, the continuous progress of knowledge of the anatomy and physiology of the epidural space has allowed the development of different techniques to locate this space while increasing both the safety and efficacy of the procedure. The most common techniques used today are based on the two main characteristics of the epidural space: the difference in distensibility between the ligamentum flavum and the epidural space, and the existence of negative pressure within the epidural space. However, over recent years, technological advances have allowed the development of new techniques to locate the epidural space based on other physical properties of tissues. Some are still in the experimental phase, but others, like ultrasound-location have reached a clinical phase and are being used increasingly in daily practice.

  5. Nonlinear modulation technique for NDE with air-coupled ultrasound.

    PubMed

    Ballad, E M; Vezirov, S Yu; Pfleiderer, K; Solodov, I Yu; Busse, G

    2004-04-01

    The present study is aimed at expanding flexibility and application area of nonlinear acoustic modulation (NAM-) technique by combining the benefits of noncontact ultrasound excitation (remote locating and imaging of defects) with sensitivity of nonlinear methods in a new air-coupled NAM-version. A pair of focused air-coupled transducers was used to generate and receive (high-frequency) longitudinal or flexural waves in plate-like samples. Low-frequency (LF-) vibrations were excited with a shaker or a loudspeaker. Temporal and spectral analysis of the output signal revealed an extremely efficient nonlinear amplitude modulation and multiple frequency side-bands for sound transmission and flexural wave propagation through cracked defects. On the contrary, a negligible modulation was observed for large and medium scale inclusions and material inhomogeneities (linear defects). A new subharmonic mode of the NAM was observed at high excitation levels. It was also shown for the first time that nonlinear vibrations of cracks resulted in radiation of a very high-order harmonics (well above 100) of the driving excitation in air that enabled imaging of cracks remotely by registration their highly nonlinear "acoustic emission" with air-coupled transducers.

  6. Healing of apical periodontitis through modern endodontic retreatment techniques.

    PubMed

    Ray, Jarom J; Kirkpatrick, Timothy C

    2013-01-01

    The presence of apical periodontitis in teeth which have undergone initial root canal treatment is largely attributed to bacteria residing in or invading from the apical root canal space. Bacteria-associated apical periodontitis will not heal spontaneously, nor will systemic antibiotics eradicate the infection. Only endodontic retreatment, endodontic surgery, or extraction will control the bacterial etiology. Modern retreatment is an effective means of addressing apical periodontitis. A mandibular premolar with apical periodontitis, apical root resorption, and overfilled gutta percha was retreated with post removal, retrieval of gutta percha from beyond the apex, ultrasonic irrigation and disinfection, and placement of a collagen internal matrix to facilitate a well-controlled MTA apical fill. The magnification and illumination imparted by the operating microscope was integral to achievement of treatment objectives. The patient's symptoms were resolved and complete osseous healing occurred. During treatment planning, clinicians should consider the capability of modern endodontic techniques to overcome technical challenges, often allowing the natural dentition to be preserved and restored to function days after retreatment.

  7. Development of Impurity Profiling Methods Using Modern Analytical Techniques.

    PubMed

    Ramachandra, Bondigalla

    2017-01-02

    This review gives a brief introduction about the process- and product-related impurities and emphasizes on the development of novel analytical methods for their determination. It describes the application of modern analytical techniques, particularly the ultra-performance liquid chromatography (UPLC), liquid chromatography-mass spectrometry (LC-MS), high-resolution mass spectrometry (HRMS), gas chromatography-mass spectrometry (GC-MS) and high-performance thin layer chromatography (HPTLC). In addition to that, the application of nuclear magnetic resonance (NMR) spectroscopy was also discussed for the characterization of impurities and degradation products. The significance of the quality, efficacy and safety of drug substances/products, including the source of impurities, kinds of impurities, adverse effects by the presence of impurities, quality control of impurities, necessity for the development of impurity profiling methods, identification of impurities and regulatory aspects has been discussed. Other important aspects that have been discussed are forced degradation studies and the development of stability indicating assay methods.

  8. [A preliminary study on data mining techniques for utilizing the breast ultrasound database].

    PubMed

    Peng, Yulan; Zhang, Heqing; Jing, Jigang; Ma, Buyun; Lu, Xiao; Tang, Chong; Nie, Shan; Liu, Ying; Qin, Yuzhou; Luo, Yan

    2010-08-01

    Based on the breast ultrasound database of West China Hospital from January 1, 2002 to December 31, 2007, a study of data mining techniques for utilizing the diagnostic information of breast ultrasound and breast pathology was carried out. An innovative computerized retrieval system was invented. With the visual user interface of the system, the data of benignancy or malignancy diagnosed by ultrasound and pathologic examination, and the data on the diagnostic correlation of ultrasound and pathology were obtained, respectively. The qualities of data mining were 99. 98%-100%. By means of the retrieval system, the users can secure numerous data from the breast ultrasound database rapidly and accurately; so it contributes to the rational utilization of information from medical database for serving various medical studies. This method may also be helpful for doctors to utilize ultrasound database in other fields.

  9. A Robust Model-Based Coding Technique for Ultrasound Video

    NASA Technical Reports Server (NTRS)

    Docef, Alen; Smith, Mark J. T.

    1995-01-01

    This paper introduces a new approach to coding ultrasound video, the intended application being very low bit rate coding for transmission over low cost phone lines. The method exploits both the characteristic noise and the quasi-periodic nature of the signal. Data compression ratios between 250:1 and 1000:1 are shown to be possible, which is sufficient for transmission over ISDN and conventional phone lines. Preliminary results show this approach to be promising for remote ultrasound examinations.

  10. Characterization of controlled bone defects using 2D and 3D ultrasound imaging techniques.

    PubMed

    Parmar, Biren J; Longsine, Whitney; Sabonghy, Eric P; Han, Arum; Tasciotti, Ennio; Weiner, Bradley K; Ferrari, Mauro; Righetti, Raffaella

    2010-08-21

    Ultrasound is emerging as an attractive alternative modality to standard x-ray and CT methods for bone assessment applications. As of today, however, there is a lack of systematic studies that investigate the performance of diagnostic ultrasound techniques in bone imaging applications. This study aims at understanding the performance limitations of new ultrasound techniques for imaging bones in controlled experiments in vitro. Experiments are performed on samples of mammalian and non-mammalian bones with controlled defects with size ranging from 400 microm to 5 mm. Ultrasound findings are statistically compared with those obtained from the same samples using standard x-ray imaging modalities and optical microscopy. The results of this study demonstrate that it is feasible to use diagnostic ultrasound imaging techniques to assess sub-millimeter bone defects in real time and with high accuracy and precision. These results also demonstrate that ultrasound imaging techniques perform comparably better than x-ray imaging and optical imaging methods, in the assessment of a wide range of controlled defects both in mammalian and non-mammalian bones. In the future, ultrasound imaging techniques might provide a cost-effective, real-time, safe and portable diagnostic tool for bone imaging applications.

  11. In situ sensor techniques in modern bioprocess monitoring.

    PubMed

    Beutel, Sascha; Henkel, Steffen

    2011-09-01

    New reactor concepts as multi-parallel screening systems or disposable bioreactor systems for decentralized and reproducible production increase the need for new and easy applicable sensor technologies to access data for process control. These sophisticated reactor systems require sensors to work with the lowest sampling volumes or, even better, to measure directly in situ, but in situ sensors are directly incorporated into a reactor or fermenter within the sterility barrier and have therefore to stand the sterilization procedures. Consequently, these in situ sensor technologies should enable the measurement of multi-analytes simultaneously online and in real-time at a low price for the robust sensing element. Current research therefore focuses on the implementation of noninvasive spectroscopic and optical technologies, and tries to employ them through fiber optics attached to disposable sensing connectors. Spectroscopic methods reach from ultraviolet to infrared and further comprising fluorescence and Raman spectroscopy. Also, optic techniques like microscopy are adapted for the direct use in bioreactor systems (Ulber et al. in Anal Bioanal Chem 376:342-348, 2003) as well as various electrochemical methods (Joo and Brown in Chem Rev 108:638-651, 2008). This review shows the variety of modern in situ sensing principles in bioprocess monitoring with emphasis on spectroscopic and optical techniques and the progress in the adaption to latest reactor concepts.

  12. Ultrasound Imaging Techniques for Spatiotemporal Characterization of Composition, Microstructure, and Mechanical Properties in Tissue Engineering.

    PubMed

    Deng, Cheri X; Hong, Xiaowei; Stegemann, Jan P

    2016-08-01

    Ultrasound techniques are increasingly being used to quantitatively characterize both native and engineered tissues. This review provides an overview and selected examples of the main techniques used in these applications. Grayscale imaging has been used to characterize extracellular matrix deposition, and quantitative ultrasound imaging based on the integrated backscatter coefficient has been applied to estimating cell concentrations and matrix morphology in tissue engineering. Spectral analysis has been employed to characterize the concentration and spatial distribution of mineral particles in a construct, as well as to monitor mineral deposition by cells over time. Ultrasound techniques have also been used to measure the mechanical properties of native and engineered tissues. Conventional ultrasound elasticity imaging and acoustic radiation force imaging have been applied to detect regions of altered stiffness within tissues. Sonorheometry and monitoring of steady-state excitation and recovery have been used to characterize viscoelastic properties of tissue using a single transducer to both deform and image the sample. Dual-mode ultrasound elastography uses separate ultrasound transducers to produce a more potent deformation force to microscale characterization of viscoelasticity of hydrogel constructs. These ultrasound-based techniques have high potential to impact the field of tissue engineering as they are further developed and their range of applications expands.

  13. Ultrasound of the elbow: Examination techniques and US appearance of the normal and pathologic joint.

    PubMed

    Draghi, F; Danesino, G M; de Gautard, R; Bianchi, S

    2007-06-01

    Ultrasound studies are frequently requested for the work-up of patients with local elbow pain, which is generally caused by overuse syndromes, trauma, inflammatory diseases, or neuropathies. The technique used to examine this joint will vary to some extent depending on the precise location of the pain and other clinical findings. The aim of this article is to describe the standard technique used for elbow ultrasound, the normal anatomy of the joint, and the appearance on ultrasound of normal elbow anatomy and the alterations associated with some of the more common disorders affecting this joint.

  14. Osteotomy in direct sinus lift. A comparative study of the rotary technique and ultrasound

    PubMed Central

    Peñarrocha-Diago, Miguel; Sanchez-Recio, Cristina; Peñarrocha-Oltra, David; Romero-Millán, Javier

    2012-01-01

    Purpose: The present study investigates sinus membrane rupture in direct maxillary sinus lift with the rotary technique and with ultrasound, examining the survival of implants placed after sinus augmentation, and analyzing the bone gain obtained after the operation and 12 months after placement of the prosthetic restoration. Material and Methods: A retrospective study was made of 45 patients requiring maxillary sinus lift or augmentation for implant-prosthetic rehabilitation. Use was made of the hand piece and ostectomy drills for the rotary technique, and of specific tips for ultrasound. The implant success criteria were based on those developed by Buser. The bone gain obtained as a result of sinus lift was calculated from the postoperative panoramic X-rays. Results: A total of 57 direct elevations of the maxillary sinus were carried out: 32 with the rotary technique and 25 with ultrasound. Perforations of Schneider’s membrane with the rotary technique and ultrasound occurred in 7% and 1.7% of the cases, respectively, with membrane integrity being preserved in 91.2%. Of the 100 implants placed, 5 failed after one year of follow-up in the rotary technique group, while one implant failed in the ultrasound group. The rotary technique in turn afforded a bone gain of 5.9 mm, versus 6.7 mm with ultrasound. Conclusions: Perforations of the membrane sinusal in direct lift were more frequent with the rotary technique (7%) than with ultrasound (1.7%). Implant survival and bone gain were both greater when ultrasound was used. Key words:Bone sectioning, maxillary sinus augmentation, piezosurgery. PMID:22143735

  15. Evaluation of ultrasound techniques for brain injury detection

    NASA Astrophysics Data System (ADS)

    Mobley, Joel; Kasili, Paul M.; Norton, Stephen J.; Vo-Dinh, Tuan

    1998-05-01

    In this work, we examine the physics underlying wave propagation in the head to evaluate various ultrasonic transducers for use in a brian injury detection device. The results of measurements of the attenuation coefficient and phase velocity for ultrasonic propagation in samples of brain tissue and skull bone from sheep are presented. The material properties are then used to investigate the propagation of ultrasonic pressure fields in the head. The ultrasound fields for three different transducers are calculated for propagation in a simulated brain/skull model. The model is constructed using speed-of-sound and mass density values of the two tissue types. The impact of the attenuation on the ultrasound fields is then examined. Finally, the relevant points drawn from these discussions are summarized. We hope to minimize the confounding effects of the skull by using sub-MHz ultrasound while maintaining the necessary temporal and spatial resolution to successfully detect injury in the brain.

  16. Evaluation of frequency-dependent ultrasound attenuation in transparent medium using focused shadowgraph technique

    NASA Astrophysics Data System (ADS)

    Iijima, Yukina; Kudo, Nobuki

    2017-07-01

    Acoustic fields of a short-pulsed ultrasound propagating through a transparent medium with ultrasound attenuation were visualized by the focused shadowgraph technique. A brightness waveform and its spatial integrations were derived from a visualized field image and compared with a pressure waveform measured by a membrane hydrophone. The experimental results showed that first-order integration of the brightness wave has good agreement with the pressure waveforms. Frequency-dependent attenuation of the pulse propagating through castor oil was derived from brightness and pressure waveforms, and attenuation coefficients determined from focused shadowgraphy and hydrophone techniques showed good agreement. The results suggest the usefulness of the shadowgraph technique not only for the visualization of ultrasound fields but also for noncontact estimation of rough pressure waveforms and correct ultrasound attenuation.

  17. Point-of-care cardiac ultrasound techniques in the physical examination: better at the bedside.

    PubMed

    Kimura, Bruce J

    2017-03-04

    The development of hand-carried, battery-powered ultrasound devices has created a new practice in ultrasound diagnostic imaging, called 'point-of-care' ultrasound (POCUS). Capitalising on device portability, POCUS is marked by brief and limited ultrasound imaging performed by the physician at the bedside to increase diagnostic accuracy and expediency. The natural evolution of POCUS techniques in general medicine, particularly with pocket-sized devices, may be in the development of a basic ultrasound examination similar to the use of the binaural stethoscope. This paper will specifically review how POCUS improves the limited sensitivity of the current practice of traditional cardiac physical examination by both cardiologists and non-cardiologists. Signs of left ventricular systolic dysfunction, left atrial enlargement, lung congestion and elevated central venous pressures are often missed by physical techniques but can be easily detected by POCUS and have prognostic and treatment implications. Creating a general set of repetitive imaging skills for these entities for application on all patients during routine examination will standardise and reduce heterogeneity in cardiac bedside ultrasound applications, simplify teaching curricula, enhance learning and recollection, and unify competency thresholds and practice. The addition of POCUS to standard physical examination techniques in cardiovascular medicine will result in an ultrasound-augmented cardiac physical examination that reaffirms the value of bedside diagnosis.

  18. Assess sleep stage by modern signal processing techniques.

    PubMed

    Wu, Hau-tieng; Talmon, Ronen; Lo, Yu-Lun

    2015-04-01

    In this paper, two modern adaptive signal processing techniques, empirical intrinsic geometry and synchrosqueezing transform, are applied to quantify different dynamical features of the respiratory and electroencephalographic signals. We show that the proposed features are theoretically rigorously supported, as well as capture the sleep information hidden inside the signals. The features are used as input to multiclass support vector machines with the radial basis function to automatically classify sleep stages. The effectiveness of the classification based on the proposed features is shown to be comparable to human expert classification-the proposed classification of awake, REM, N1, N2, and N3 sleeping stages based on the respiratory signal (resp. respiratory and EEG signals) has the overall accuracy 81.7% (resp. 89.3%) in the relatively normal subject group. In addition, by examining the combination of the respiratory signal with the electroencephalographic signal, we conclude that the respiratory signal consists of ample sleep information, which supplements to the information stored in the electroencephalographic signal.

  19. Inside Out: Modern Imaging Techniques to Reveal Animal Anatomy

    PubMed Central

    Lauridsen, Henrik; Hansen, Kasper; Wang, Tobias; Agger, Peter; Andersen, Jonas L.; Knudsen, Peter S.; Rasmussen, Anne S.; Uhrenholt, Lars; Pedersen, Michael

    2011-01-01

    Animal anatomy has traditionally relied on detailed dissections to produce anatomical illustrations, but modern imaging modalities, such as MRI and CT, now represent an enormous resource that allows for fast non-invasive visualizations of animal anatomy in living animals. These modalities also allow for creation of three-dimensional representations that can be of considerable value in the dissemination of anatomical studies. In this methodological review, we present our experiences using MRI, CT and μCT to create advanced representation of animal anatomy, including bones, inner organs and blood vessels in a variety of animals, including fish, amphibians, reptiles, mammals, and spiders. The images have a similar quality to most traditional anatomical drawings and are presented together with interactive movies of the anatomical structures, where the object can be viewed from different angles. Given that clinical scanners found in the majority of larger hospitals are fully suitable for these purposes, we encourage biologists to take advantage of these imaging techniques in creation of three-dimensional graphical representations of internal structures. PMID:21445356

  20. Modern Radar Techniques for Geophysical Applications: Two Examples

    NASA Technical Reports Server (NTRS)

    Arokiasamy, B. J.; Bianchi, C.; Sciacca, U.; Tutone, G.; Zirizzotti, A.; Zuccheretti, E.

    2005-01-01

    The last decade of the evolution of radar was heavily influenced by the rapid increase in the information processing capabilities. Advances in solid state radio HF devices, digital technology, computing architectures and software offered the designers to develop very efficient radars. In designing modern radars the emphasis goes towards the simplification of the system hardware, reduction of overall power, which is compensated by coding and real time signal processing techniques. Radars are commonly employed in geophysical radio soundings like probing the ionosphere; stratosphere-mesosphere measurement, weather forecast, GPR and radio-glaciology etc. In the laboratorio di Geofisica Ambientale of the Istituto Nazionale di Geofisica e Vulcanologia (INGV), Rome, Italy, we developed two pulse compression radars. The first is a HF radar called AIS-INGV; Advanced Ionospheric Sounder designed both for the purpose of research and for routine service of the HF radio wave propagation forecast. The second is a VHF radar called GLACIORADAR, which will be substituting the high power envelope radar used by the Italian Glaciological group. This will be employed in studying the sub glacial structures of Antarctica, giving information about layering, the bed rock and sub glacial lakes if present. These are low power radars, which heavily rely on advanced hardware and powerful real time signal processing. Additional information is included in the original extended abstract.

  1. An investigative graduate laboratory course for teaching modern DNA techniques.

    PubMed

    de Lencastre, Alexandre; Thomas Torello, A; Keller, Lani C

    2017-07-08

    This graduate-level DNA methods laboratory course is designed to model a discovery-based research project and engages students in both traditional DNA analysis methods and modern recombinant DNA cloning techniques. In the first part of the course, students clone the Drosophila ortholog of a human disease gene of their choosing using Gateway(®) cloning. In the second part of the course, students examine the expression of their gene of interest in human cell lines by reverse transcription PCR and learn how to analyze data from quantitative reverse transcription PCR (qRT-PCR) experiments. The adaptability of the Gateway(®) cloning system is ideally suited for students to design and create different types of expression constructs to achieve a particular experimental goal (e.g., protein purification, expression in cell culture, and/or subcellular localization), and the genes chosen can be aligned to the research interests of the instructor and/or ongoing research in a department. Student evaluations indicate that the course fostered a genuine excitement for research and in depth knowledge of both the techniques performed and the theory behind them. Our long-term goal is to incorporate this DNA methods laboratory as the foundation for an integrated laboratory sequence for the Master of Science degree program in Molecular and Cellular Biology at Quinnipiac University, where students use the reagents and concepts they developed in this course in subsequent laboratory courses, including a protein methods and cell culture laboratory. © 2017 by The International Union of Biochemistry and Molecular Biology, 45(4):351-359, 2017. © 2017 The International Union of Biochemistry and Molecular Biology.

  2. Ultrasound Use in Urinary Stones: Adapting Old Technology for a Modern-Day Disease.

    PubMed

    Tzou, David T; Usawachintachit, Manint; Taguchi, Kazumi; Chi, Thomas

    2017-04-01

    Ultrasound has become a mainstay tool in urologists' armamentarium for the diagnosis and management of nephrolithiasis. From starting as a rudimentary form of imaging, it has come to play a more prominent role over time, paralleling evolution in ultrasound technology. Throughout the medical community there is a growing emphasis on reducing the amount of ionizing radiation delivered to patients during routine imaging. As such there has been a resurgence of interest in ultrasound given its lack of associated radiation exposure and proven effectiveness as a diagnostic and therapeutic imaging modality. Herein, we provide a review of the history of ultrasound, how the use of ultrasound is expanding in both diagnosis and treatment of urinary stone disease, and finally how promising applications of ultrasound are shaping the future of kidney stone management.

  3. Quality Improvement of Liver Ultrasound Images Using Fuzzy Techniques

    PubMed Central

    Bayani, Azadeh; Langarizadeh, Mostafa; Radmard, Amir Reza; Nejad, Ahmadreza Farzaneh

    2016-01-01

    Background: Liver ultrasound images are so common and are applied so often to diagnose diffuse liver diseases like fatty liver. However, the low quality of such images makes it difficult to analyze them and diagnose diseases. The purpose of this study, therefore, is to improve the contrast and quality of liver ultrasound images. Methods: In this study, a number of image contrast enhancement algorithms which are based on fuzzy logic were applied to liver ultrasound images - in which the view of kidney is observable - using Matlab2013b to improve the image contrast and quality which has a fuzzy definition; just like image contrast improvement algorithms using a fuzzy intensification operator, contrast improvement algorithms applying fuzzy image histogram hyperbolization, and contrast improvement algorithms by fuzzy IF-THEN rules. Results: With the measurement of Mean Squared Error and Peak Signal to Noise Ratio obtained from different images, fuzzy methods provided better results, and their implementation - compared with histogram equalization method - led both to the improvement of contrast and visual quality of images and to the improvement of liver segmentation algorithms results in images. Conclusion: Comparison of the four algorithms revealed the power of fuzzy logic in improving image contrast compared with traditional image processing algorithms. Moreover, contrast improvement algorithm based on a fuzzy intensification operator was selected as the strongest algorithm considering the measured indicators. This method can also be used in future studies on other ultrasound images for quality improvement and other image processing and analysis applications. PMID:28077898

  4. Quality Improvement of Liver Ultrasound Images Using Fuzzy Techniques.

    PubMed

    Bayani, Azadeh; Langarizadeh, Mostafa; Radmard, Amir Reza; Nejad, Ahmadreza Farzaneh

    2016-12-01

    Liver ultrasound images are so common and are applied so often to diagnose diffuse liver diseases like fatty liver. However, the low quality of such images makes it difficult to analyze them and diagnose diseases. The purpose of this study, therefore, is to improve the contrast and quality of liver ultrasound images. In this study, a number of image contrast enhancement algorithms which are based on fuzzy logic were applied to liver ultrasound images - in which the view of kidney is observable - using Matlab2013b to improve the image contrast and quality which has a fuzzy definition; just like image contrast improvement algorithms using a fuzzy intensification operator, contrast improvement algorithms applying fuzzy image histogram hyperbolization, and contrast improvement algorithms by fuzzy IF-THEN rules. With the measurement of Mean Squared Error and Peak Signal to Noise Ratio obtained from different images, fuzzy methods provided better results, and their implementation - compared with histogram equalization method - led both to the improvement of contrast and visual quality of images and to the improvement of liver segmentation algorithms results in images. Comparison of the four algorithms revealed the power of fuzzy logic in improving image contrast compared with traditional image processing algorithms. Moreover, contrast improvement algorithm based on a fuzzy intensification operator was selected as the strongest algorithm considering the measured indicators. This method can also be used in future studies on other ultrasound images for quality improvement and other image processing and analysis applications.

  5. Ultrasound in sports medicine: relevance of emerging techniques to clinical care of athletes.

    PubMed

    Yim, Eugene Sun; Corrado, Gianmichael

    2012-08-01

    The applications of ultrasound in managing the clinical care of athletes have been expanding over the past decade. This review provides an analysis of the research that has been published regarding the use of ultrasound in athletes and focuses on how these emerging techniques can impact the clinical management of athletes by sports medicine physicians. Electronic database literature searches were performed using the subject terms 'ultrasound' and 'athletes' from the years 2003 to 2012. The following databases were searched: PubMed, Web of Science, Cochrane Library, CINAHL, and SPORTDiscus™. The search produced 617 articles in total, with a predominance of articles focused on cardiac and musculoskeletal ultrasound. 266 of the studies involved application of ultrasound in evaluating the cardiovascular properties of athletes, and 151 studies involved musculoskeletal ultrasound. Other applications of ultrasound included abdominal, vascular, bone density and volume status. New techniques in echocardiography have made significant contributions to the understanding of the physiological changes that occur in the athlete's heart in response to the haemodynamic stress associated with different types of activity. The likely application of these techniques will be in managing athletes with hypertrophic cardiomyopathy, and the techniques are near ready for application into clinical practice. These techniques are highly specialized, however, and will require referral to dedicated laboratories to influence the clinical management of athletes. Investigation of aortic root pathology and pulmonary vascular haemodynamics are also emerging, but will require additional studies with larger numbers and outcomes analysis to validate their clinical utility. Some of these techniques are relatively simple, and thus hold the potential to enter clinical management in a point-of-care fashion. Musculoskeletal ultrasound has demonstrated a number of diagnostic and therapeutic techniques

  6. [Modern ultrasound methods of examination in clinical ophthalmology. Background problems and future prospects].

    PubMed

    Kharlap, S I

    2003-01-01

    Historic aspects of ultrasound diagnostics in ophthalmology are described. The technological development of ultrasound diagnostic systems and the clinical application of different ultrasound modes in examining the eye and its choroids are traced back. The efficiency of Doppler mapping in the mode of three-dimension reconstruction at examining the orbital vascular system is evaluated. An experience obtained at the Research Institute for Eye Disease of the Russian Academy of Medical Sciences and outlooks for the diagnostic usage of computer ultrasound in clinical ophthalmology and angiologia are presented.

  7. Comparison of ultrasound-guided and fluoroscopy-assisted antegrade common femoral artery puncture techniques.

    PubMed

    Slattery, Michael M; Goh, Gerard S; Power, Sarah; Given, Mark F; McGrath, Frank P; Lee, Michael J

    2015-06-01

    To prospectively compare the procedural time and complication rates of ultrasound-guided and fluoroscopy-assisted antegrade common femoral artery (CFA) puncture techniques. Hundred consecutive patients, undergoing a vascular procedure for which an antegrade approach was deemed necessary/desirable, were randomly assigned to undergo either ultrasound-guided or fluoroscopy-assisted CFA puncture. Time taken from administration of local anaesthetic to vascular sheath insertion in the superficial femoral artery (SFA), patients' age, body mass index (BMI), fluoroscopy radiation dose, haemostasis method and immediate complications were recorded. Mean and median values were calculated and statistically analysed with unpaired t tests. Sixty-nine male and 31 female patients underwent antegrade puncture (mean age 66.7 years). The mean BMI was 25.7 for the ultrasound-guided (n = 53) and 25.3 for the fluoroscopy-assisted (n = 47) groups. The mean time taken for the ultrasound-guided puncture was 7 min 46 s and for the fluoroscopy-assisted technique was 9 min 41 s (p = 0.021). Mean fluoroscopy dose area product in the fluoroscopy group was 199 cGy cm(2). Complications included two groin haematomas in the ultrasound-guided group and two retroperitoneal haematomas and one direct SFA puncture in the fluoroscopy-assisted group. Ultrasound-guided technique is faster and safer for antegrade CFA puncture when compared to the fluoroscopic-assisted technique alone.

  8. Degradation of glass artifacts: application of modern surface analytical techniques.

    PubMed

    Melcher, Michael; Wiesinger, Rita; Schreiner, Manfred

    2010-06-15

    A detailed understanding of the stability of glasses toward liquid or atmospheric attack is of considerable importance for preserving numerous objects of our cultural heritage. Glasses produced in the ancient periods (Egyptian, Greek, or Roman glasses), as well as modern glass, can be classified as soda-lime-silica glasses. In contrast, potash was used as a flux in medieval Northern Europe for the production of window panes for churches and cathedrals. The particular chemical composition of these potash-lime-silica glasses (low in silica and rich in alkali and alkaline earth components), in combination with increased levels of acidifying gases (such as SO(2), CO(2), NO(x), or O(3)) and airborne particulate matter in today's urban or industrial atmospheres, has resulted in severe degradation of important cultural relics, particularly over the last century. Rapid developments in the fields of microelectronics and computer sciences, however, have contributed to the development of a variety of nondestructive, surface analytical techniques for the scientific investigation and material characterization of these unique and valuable objects. These methods include scanning electron microscopy in combination with energy- or wavelength-dispersive spectrometry (SEM/EDX or SEM/WDX), secondary ion mass spectrometry (SIMS), and atomic force microscopy (AFM). In this Account, we address glass analysis and weathering mechanisms, exploring the possibilities (and limitations) of modern analytical techniques. Corrosion by liquid substances is well investigated in the glass literature. In a tremendous number of case studies, the basic reaction between aqueous solutions and the glass surfaces was identified as an ion-exchange reaction between hydrogen-bearing species of the attacking liquid and the alkali and alkaline earth ions in the glass, causing a depletion of the latter in the outermost surface layers. Although mechanistic analogies to liquid corrosion are obvious, atmospheric

  9. An update around the evidence base for the lower extremity ultrasound regional block technique

    PubMed Central

    Fanelli, Andrea; Ghisi, Daniela; Melotti, Rita Maria

    2016-01-01

    Ultrasound guidance currently represents the gold standard for regional anesthesia. In particular for lower extremity blocks, despite the heterogeneity and the lack of large randomized controlled trials, current literature shows a modest improvement in block onset and quality compared with other localization techniques. This review aims to present the most recent findings on the application of ultrasound guidance for each single lower extremity approach. PMID:26918177

  10. Ultrasound Recycling of Natural Rubber, Characterized with NMR Techniques.

    NASA Astrophysics Data System (ADS)

    Massey, J. C.; Massey, J. L.; von Meerwall, E.; Hong, C.-K.; Isayev, A.

    1999-04-01

    We have used ^1H NMR transverse relaxation and pulsed-gradient spin-echo self-diffusion measurements at 70^oC, and ^13C solids NMR, to study molecular and segmental mobilities in natural rubber before and after crosslinking, and after subsequent devulcanization using intense ultrasound. NMR relaxation does not distinguish entanglements and crosslinks, but unentangled sol is evident as a long T2 component. Ultrasound reactor settings affect the amount of sol generated; unentangled sol is of molecular weight M between approx. 2,000 and 10,000 g/mol. Some two-thirds of total extractable sol consists of fragments with M greater than 10,000. Samples contain some 2 percent of inert light material (M less than about 400). Mobility of sol molecules and gel segments increases as more mobile sol is produced. As in our analogous study of SBR devulcanization, main-chain (^13C) mobility differs significantly from proton mobility dominated by interchain motions. But in NR neither the glass transition temperature nor the light sol diffusion rate is greatly affected by ultrasound exposure.

  11. Comparison of thyroid segmentation techniques for 3D ultrasound

    NASA Astrophysics Data System (ADS)

    Wunderling, T.; Golla, B.; Poudel, P.; Arens, C.; Friebe, M.; Hansen, C.

    2017-02-01

    The segmentation of the thyroid in ultrasound images is a field of active research. The thyroid is a gland of the endocrine system and regulates several body functions. Measuring the volume of the thyroid is regular practice of diagnosing pathological changes. In this work, we compare three approaches for semi-automatic thyroid segmentation in freehand-tracked three-dimensional ultrasound images. The approaches are based on level set, graph cut and feature classification. For validation, sixteen 3D ultrasound records were created with ground truth segmentations, which we make publicly available. The properties analyzed are the Dice coefficient when compared against the ground truth reference and the effort of required interaction. Our results show that in terms of Dice coefficient, all algorithms perform similarly. For interaction, however, each algorithm has advantages over the other. The graph cut-based approach gives the practitioner direct influence on the final segmentation. Level set and feature classifier require less interaction, but offer less control over the result. All three compared methods show promising results for future work and provide several possible extensions.

  12. A novel software-based technique for quantifying placental calcifications and infarctions from ultrasound

    NASA Astrophysics Data System (ADS)

    Ryan, John T.; McAuliffe, Fionnuala; Higgins, Mary; Stanton, Marie; Brennan, Patrick

    2008-03-01

    In obstetrics, antenatal ultrasound assessment of placental morphology comprises an important part of the estimation of fetal health. Ultrasound analysis of the placenta may reveal abnormalities such as placental calcification and infarcts. Current methods of quantification of these abnormalities are subjective and involve a grading system of Grannum stages I-III. The aim of this project is to develop a software tool that quantifies semi-automatically placental ultrasound images and facilitates the assessment of placental morphology. We have developed a 2D ultrasound imaging software tool that allows the obstetrician or sonographer to define the placental region of interest. A secondary reference map is created for use in our quantification algorithm. Using a slider technique the user can easily define an upper threshold based on high intensity for calcification classification and a lower threshold to define infarction regions based on low intensity within the defined region of interest. The percentage of the placental area that is calcified and also the percentage of infarction is calculated and this is the basis of our new metric. Ultrasound images of abnormal and normal placentas have been acquired to aid our software development. A full clinical prospective evaluation is currently being performed and we are currently applying this technology to the three-dimensional ultrasound domain. We have developed a novel software-based technique for calculating the extent of placental calcification and infarction, providing a new metric in this field. Our new metric may provide a more accurate measurement of placental calcification and infarction than current techniques.

  13. Developing High-Frequency Quantitative Ultrasound Techniques to Characterize Three-Dimensional Engineered Tissues

    NASA Astrophysics Data System (ADS)

    Mercado, Karla Patricia E.

    Tissue engineering holds great promise for the repair or replacement of native tissues and organs. Further advancements in the fabrication of functional engineered tissues are partly dependent on developing new and improved technologies to monitor the properties of engineered tissues volumetrically, quantitatively, noninvasively, and nondestructively over time. Currently, engineered tissues are evaluated during fabrication using histology, biochemical assays, and direct mechanical tests. However, these techniques destroy tissue samples and, therefore, lack the capability for real-time, longitudinal monitoring. The research reported in this thesis developed nondestructive, noninvasive approaches to characterize the structural, biological, and mechanical properties of 3-D engineered tissues using high-frequency quantitative ultrasound and elastography technologies. A quantitative ultrasound technique, using a system-independent parameter known as the integrated backscatter coefficient (IBC), was employed to visualize and quantify structural properties of engineered tissues. Specifically, the IBC was demonstrated to estimate cell concentration and quantitatively detect differences in the microstructure of 3-D collagen hydrogels. Additionally, the feasibility of an ultrasound elastography technique called Single Tracking Location Acoustic Radiation Force Impulse (STL-ARFI) imaging was demonstrated for estimating the shear moduli of 3-D engineered tissues. High-frequency ultrasound techniques can be easily integrated into sterile environments necessary for tissue engineering. Furthermore, these high-frequency quantitative ultrasound techniques can enable noninvasive, volumetric characterization of the structural, biological, and mechanical properties of engineered tissues during fabrication and post-implantation.

  14. Increasing the reliability of ecological models using modern software engineering techniques

    Treesearch

    Robert M. Scheller; Brian R. Sturtevant; Eric J. Gustafson; Brendan C. Ward; David J. Mladenoff

    2009-01-01

    Modern software development techniques are largely unknown to ecologists. Typically, ecological models and other software tools are developed for limited research purposes, and additional capabilities are added later, usually in an ad hoc manner. Modern software engineering techniques can substantially increase scientific rigor and confidence in ecological models and...

  15. Ultrasound

    MedlinePlus Videos and Cool Tools

    ... baby's development in the uterus. Ultrasound uses inaudible sound waves to produce a two-dimensional image of the baby while inside the mother's uterus. The sound waves bounce off solid structures in the body ...

  16. Ultrasound

    MedlinePlus

    ... called multiples) To screen for birth defects, like spina bifida or heart defects . Screening means seeing if your ... example, if the ultrasound shows your baby has spina bifida, she may be treated in the womb before ...

  17. Ultrasound

    MedlinePlus

    ... a pregnant woman and assess her fetus Diagnose gallbladder disease Evaluate flow in blood vessels Guide a ... For some ultrasound exams, such as of the gallbladder, your doctor may ask that you not eat ...

  18. The measurements of ultrasound parameters on calcaneus by two-sided interrogation techniques

    NASA Astrophysics Data System (ADS)

    Chen, Pei-Jarn; Chen, Tainsong; Lu, Ming-Chang; Yao, Wei-Jen

    2005-06-01

    Recently, ultrasound techniques have become an important alternative in the assessment of osteoporosis. The speed of sound (SOS) and broadband ultrasound attenuation (BUA) on calcaneus are commonly used in an ultrasound densitometer for osteoporosis evaluation. However, the quantitative ultrasound (QUS) parameters provided by a densitometer using most commercial ultrasound instruments are based on the assumption of a fixed bone thickness. Information on bone thickness is a critical factor for accurate estimation of SOS through conventional approaches; yet, the thickness of bone tissue is not available through in vivo measurements and it is almost impossible to obtain the thickness of bone tissue via conventional approaches. Therefore, the SOS measurements will be incorrect. The purpose of this work is to develop a two-sided interrogation technique for the SOS measurements that is less susceptible to bone thickness. The results show that this proposed technique can obtain a better SOS estimation on bone tissue. Using bone phantoms that mimic actual tissue, the validity of the approach is confirmed with measurements showing high accuracy (>99%) and low standard deviation (<0.5%). Finally, the measurements of 14 healthy subjects are also reported. The results show that this technique can provide the bone thickness information to reduce the SOS estimation errors compared with the fixed bone thickness assumption.

  19. Navigated high frequency ultrasound: description of technique and clinical comparison with conventional intracranial ultrasound.

    PubMed

    Coburger, Jan; König, Ralph W; Scheuerle, Angelika; Engelke, Jens; Hlavac, Michal; Thal, Dietmar R; Wirtz, Christian Rainer

    2014-01-01

    Conventional curved or sector array ultrasound (cioUS) is the most commonly used intraoperative imaging modality worldwide. Although highly beneficial in various clinical applications, at present the impact of linear array intraoperative ultrasound (lioUS) has not been assessed for intracranial use. We provide a technical description to integrate an independent lioUS probe into a commercially available neuronavigation system and evaluate the use of navigated lioUS as a resection control in glioblastoma surgery. We performed a prospective study assessing residual tumor detection after complete microsurgical resection using either cioUS or lioUS in 15 consecutive patients. We compared the imaging findings of both ultrasound modalities in 44 sites surrounding the resection cavity. The respective findings were correlated with the histopathologic findings of tissue specimen obtained from those sites. Use of cioUS leaded to an additional resection in 9 patients, whereas lioUS detected residual tumor during all surgeries. A further resection was performed at 33 of 44 intraoperative sites (75%) based on results of lioUS alone. Resected tissue was solid tumor in 66% and infiltration zone in 34%. No false-positive or false-negative findings were seen using lioUS. There was no case of a tumor detection in cioUS combined with a negative finding in lioUS. The difference of imaging results between cioUS and lioUS was significant (sign test, P<0.001). lioUS can be used as a safe and precise tool for intracranial image-guided resection control of glioblastomas. It can be integrated in a commercially available navigation system and shows a significant higher detection rate of residual tumor compared with conventional cioUS. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Ultrasound Recycling of Silicone Rubber, Characterized with NMR Techniques

    NASA Astrophysics Data System (ADS)

    Parr, J. C.; von Meerwall, E.; Shim, S. E.; Isayev, A.

    2000-10-01

    We have used proton NMR transverse relaxation and pulsed-gradient spin-echo self-diffusion measurements at 70 deg. C to study molecular and segmental mobilities in poly (dimethyl siloxane) rubber before and after crosslinking, and after subsequent devulcanization by intense ultrasound. Transverse NMR relaxation cannot clearly distinguish the effects of entanglements and crosslinks. Hence the three distinct components of the T2 decays are attributed to entangled and crosslinked network; light sol and network fragments; and oligomers including an unreactive component of 4 percent. Devulcanization produces extractable sol dependent on cavity gap width and transducer amplitude. Our results correlate strongly with the amount of sol: all three mobilities and the amounts of the two more mobile fractions increase with sol content, but the diffusion rates decrease, likely due to a broadening of the molecular mass distribution. These results resemble those of our previous studies of ultrasound devulcanization of styrene-butadiene and natural rubbers. The main difference is the much greater extent in PDMS of loosely attached network fragments.

  1. [Inheritance and evolution of acupuncture manipulation techniques of Zhejiang acupuncture masters in modern times].

    PubMed

    Yu, Daxiong; Ma, Ruijie; Fang, Jianqiao

    2015-05-01

    There are many eminent acupuncture masters in modern times in the regions of Zhejiang province, which has developed the acupuncture schools of numerous characteristics and induces the important impacts at home and abroad. Through the literature collection on the acupuncture schools in Zhejiang and the interviews to the parties involved, it has been discovered that the acupuncture manipulation techniques of acupuncture masters in modern times are specifically featured. Those techniques are developed on the basis of Neijing (Internal Classic), Jinzhenfu (Ode to Gold Needle) and Zhenjiu Dacheng (Great Compendium of Acupuncture and Moxibustion). No matter to obey the old maxim or study by himself, every master lays the emphasis on the research and interpretation of classical theories and integrates the traditional with the modern. In the paper, the acupuncture manipulation techniques of Zhejiang acupuncture masters in modern times are stated from four aspects, named needling techniques in Internal Classic, feijingzouqi needling technique, penetrating needling technique and innovation of acupuncture manipulation.

  2. Carpal tunnel: Normal anatomy, anatomical variants and ultrasound technique

    PubMed Central

    Presazzi, A.; Bortolotto, C.; Zacchino, M.; Madonia, L.; Draghi, F.

    2011-01-01

    The carpal tunnel is an osteofibrous canal situated in the volar wrist. The boundaries are the carpal bones and the flexor retinaculum. In addition to the medial nerve, the carpal tunnel contains nine tendons: the flexor pollicis longus, the four flexor digitorum superficialis and the four flexor digitorum profundus. Ultrasound (US) study of the carpal tunnel generally involves short-axis imaging of the tendons, and in the presence of disease, long-axis imaging and dynamic maneuvers are added. There are numerous reports of anatomical variants of the wrist involving vessels, nerves, tendons and muscles, and they can all be studied by US. Some are particularly relevant from a clinical point of view and will therefore be accurately described. The anatomy is complex, and the US operator should therefore be thoroughly familiar with the normal anatomy as well as the anatomical variants that may have a role in the pathogenesis of carpal tunnel syndrome or influence treatment. PMID:23396809

  3. Carpal tunnel: Normal anatomy, anatomical variants and ultrasound technique.

    PubMed

    Presazzi, A; Bortolotto, C; Zacchino, M; Madonia, L; Draghi, F

    2011-03-01

    The carpal tunnel is an osteofibrous canal situated in the volar wrist. The boundaries are the carpal bones and the flexor retinaculum. In addition to the medial nerve, the carpal tunnel contains nine tendons: the flexor pollicis longus, the four flexor digitorum superficialis and the four flexor digitorum profundus. Ultrasound (US) study of the carpal tunnel generally involves short-axis imaging of the tendons, and in the presence of disease, long-axis imaging and dynamic maneuvers are added. There are numerous reports of anatomical variants of the wrist involving vessels, nerves, tendons and muscles, and they can all be studied by US. Some are particularly relevant from a clinical point of view and will therefore be accurately described. The anatomy is complex, and the US operator should therefore be thoroughly familiar with the normal anatomy as well as the anatomical variants that may have a role in the pathogenesis of carpal tunnel syndrome or influence treatment.

  4. Ultrasound Elastography and MR Elastography for Assessing Liver Fibrosis: Part 1, Principles and Techniques

    PubMed Central

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

    2016-01-01

    Objective The purpose of this article is to provide an overview of ultrasound and magnetic resonance elastography, including a glossary of relevant terminology, a classification of elastography techniques, and a discussion of their respective strengths and limitations. Conclusion Elastography is an emerging technique for the non-invasive assessment of mechanical tissue properties. These techniques report metrics related to tissue stiffness such as shear wave speed, magnitude of the complex shear modulus, and Young’s modulus. PMID:25905647

  5. Volume Navigation Technique for Ultrasound-Guided Biopsy of Breast Lesions Detected Only at MRI.

    PubMed

    Aribal, Erkin; Tureli, Derya; Kucukkaya, Fikret; Kaya, Handan

    2017-06-01

    The purpose of this study is to assess the utility of a volume navigation technique (VNT) for ultrasound-guided biopsy of MRI-detected, but sonographically ambiguous or occult, breast lesions. Within a recruitment period of 13 months (January 1, 2014, through February 1, 2015), 22 patients with 26 BI-RADS category 4 or 5 lesions that were detected at MRI but missed at second-look ultrasound were reimaged using a rapid sequence and a flexible body coil in a 3-T MRI scanner. Patients were supine, with three skin markers placed on the breasts. MRI volume data were coregistered to real-time ultrasound in a dedicated platform, and MRI-detected lesions (six masses, 11 nonmass enhancements, eight foci, and one architectural distortion) were sought using VNT-guided ultrasound. Five needle biopsy specimens were obtained either from each sonographically detected lesion (n = 11) or from VNT-guided sonographically localized breast volume corresponding to the MRI-detected, but still ultrasound-occult, lesions (n = 15). Histopathologic analysis revealed 18 benign and six malignant lesions. The remaining two lesions, both of which appeared as masses at MRI, were high risk and were upgraded to carcinoma after excisional biopsy. All malignant lesions underwent curative surgery; the final histopathologic diagnoses remained unchanged. Of the six malignant lesions, one was a mass, three were nonmass enhancements, and two were enhancing foci at MRI. Three malignant lesions were occult at ultrasound, and three were discerned as subtle hypoechoic changes. No benign lesion was sonographically visualized as a mass, and none progressed, with 56% disappearing at MRI performed during the follow-up period (mean, 14 months). Coregistration of MRI and real-time ultrasound enables sonographic localization of breast lesions detected at MRI only. VNT is a feasible alternative to MRI-guided biopsy of ultrasound-occult breast lesions.

  6. Comparison of Ultrasound-Guided and Fluoroscopy-Assisted Antegrade Common Femoral Artery Puncture Techniques

    SciTech Connect

    Slattery, Michael M.; Goh, Gerard S.; Power, Sarah; Given, Mark F.; McGrath, Frank P.; Lee, Michael J.

    2015-06-15

    PurposeTo prospectively compare the procedural time and complication rates of ultrasound-guided and fluoroscopy-assisted antegrade common femoral artery (CFA) puncture techniques.Materials and MethodsHundred consecutive patients, undergoing a vascular procedure for which an antegrade approach was deemed necessary/desirable, were randomly assigned to undergo either ultrasound-guided or fluoroscopy-assisted CFA puncture. Time taken from administration of local anaesthetic to vascular sheath insertion in the superficial femoral artery (SFA), patients’ age, body mass index (BMI), fluoroscopy radiation dose, haemostasis method and immediate complications were recorded. Mean and median values were calculated and statistically analysed with unpaired t tests.ResultsSixty-nine male and 31 female patients underwent antegrade puncture (mean age 66.7 years). The mean BMI was 25.7 for the ultrasound-guided (n = 53) and 25.3 for the fluoroscopy-assisted (n = 47) groups. The mean time taken for the ultrasound-guided puncture was 7 min 46 s and for the fluoroscopy-assisted technique was 9 min 41 s (p = 0.021). Mean fluoroscopy dose area product in the fluoroscopy group was 199 cGy cm{sup 2}. Complications included two groin haematomas in the ultrasound-guided group and two retroperitoneal haematomas and one direct SFA puncture in the fluoroscopy-assisted group.ConclusionUltrasound-guided technique is faster and safer for antegrade CFA puncture when compared to the fluoroscopic-assisted technique alone.

  7. Modern Computational Techniques for the HMMER Sequence Analysis

    PubMed Central

    2013-01-01

    This paper focuses on the latest research and critical reviews on modern computing architectures, software and hardware accelerated algorithms for bioinformatics data analysis with an emphasis on one of the most important sequence analysis applications—hidden Markov models (HMM). We show the detailed performance comparison of sequence analysis tools on various computing platforms recently developed in the bioinformatics society. The characteristics of the sequence analysis, such as data and compute-intensive natures, make it very attractive to optimize and parallelize by using both traditional software approach and innovated hardware acceleration technologies. PMID:25937944

  8. Ultrasound-guided trigger point injections in the cervicothoracic musculature: a new and unreported technique.

    PubMed

    Botwin, Kenneth P; Sharma, Kavita; Saliba, Romeo; Patel, Bharat C

    2008-01-01

    Myofascial pain is defined as pain that originates from myofascial trigger points in skeletal muscle. It is prevalent in regional musculoskeletal pain syndromes, either alone or in combination with other pain generators. The myofascial pain syndrome is one of the largest groups of under diagnosed and under treated medical problems encountered in clinical practice. Trigger points are commonly seen in patients with myofascial pain which is responsible for localized pain in the affected muscles as well as referred pain patterns. Correct needle placement in a myofascial trigger point is vital to prevent complications and improve efficacy of the trigger point injection to help reduce or relieve myofascial pain. In obese patients, these injections may not reach the target tissue. In the cervicothoracic spine, a misguided or misplaced injection can result in a pneumothorax. Here, we describe an ultrasound-guided trigger point injection technique to avoid this potential pitfall. Office based ultrasound-guided injection techniques for musculoskeletal disorders have been described in the literature with regard to tendon, bursa, cystic, and joint pathologies. For the interventionalist, utilizing ultrasound yields multiple advantages technically and practically, including observation of needle placement in real-time, ability to perform dynamic studies, the possibility of diagnosing musculoskeletal pathologies, avoidance of radiation exposure, reduced overall cost, and portability of equipment within the office setting. To our knowledge, the use of ultrasound guidance in performing trigger point injection in the cervicothoracic area, particularly in obese patients, has not been previously reported. A palpable trigger point in the cervicothoracic musculature was localized and marked by indenting the skin with the tip of a plastic needle cover. The skin was then sterile prepped. Then, using an ultrasound machine with sterile coupling gel and a sterile latex free transducer cover

  9. [A standardized technique for ultrasound controlled placement of a central venous catheter].

    PubMed

    Mergelsberg, M

    1991-12-01

    To reduce the rate of complications and failures in central venous catheterisation a technique for ultrasonically controlled puncture of the internal jugular vein was standardised. The puncture procedure, including the application of local anaesthesia, is continuously observed and guided by real-time ultrasound. Imaging, control and practising of the puncture are described and discussed.

  10. Ultrasound techniques for the detection of tumors and metastases in small animals.

    PubMed

    Didié, Michael; Zimmermann, Wolfram-Hubertus

    2014-01-01

    Small animals are widely used for the identification of new therapeutic targets and the evaluation of potential anticancer therapies. To study tumors and metastasis in longitudinal studies of tumor progression, fast noninvasive and easy-to-handle imaging modalities are required. Here, techniques for the analysis of tumors and metastases by ultrasound imaging are described and the potential technical pitfalls are discussed.

  11. Modern Techniques and Technologies Applied to Training and Performance Monitoring.

    PubMed

    Sands, William A; Kavanaugh, Ashley A; Murray, Steven R; McNeal, Jeni R; Jemni, Monèm

    2016-12-05

    Athlete preparation and performance continues to increase in complexity and costs. Modern coaches are shifting from reliance on personal memory, experience, and opinion to evidence from collected training load data. Training load monitoring may hold vital information for developing systems of monitoring that follow the training process with such precision that both performance prediction and day-to-day management of training become an adjunct to preparation and performance. Time series data collection and analyses in sport are still in their infancy with considerable efforts being applied in "big-data" analytics and models of the appropriate variables to monitor and methods for doing so. Training monitoring has already garnered important applications, but lacks a theoretical framework from which to develop further. As such, we propose a framework involving the following: analyses of individuals, trend analyses, rules-based analysis, and statistical process control.

  12. [Marking techniques and ultrasound guided mastografía prior to obtaining biopsy breast excisional].

    PubMed

    Navari González, Faride; Ortíz de Iturbide, María Cecilia; Zúñiga Lara, Daniel Silveiro

    2009-06-01

    Breast cancer is the most common gynecologic malignancy worldwide. Localization under ultrasound guidance or mammography prior to biopsy is one of the procedures used for diagnosis of subclinical malignant or premalignant lesions. To describe techniques for localization by mammography or ultrasound at our institution, prior to excisional breast biopsy. Localization under ultrasound guidance or mammography from July 1 to December 31, 2008 at the HospitalAngeles del Pedregal. An analysis of the category BIRADS, histopathologic results, the imaging procedure and the surgical approach. We made 78 procedures. 56% under mammography guidance and 44% by ultrasound. 23% of biopsies with histopathological result of malignancy and 77% were benign, the outcome depended on the category of BIRADS granted. Success depends on the technique of covering the lesion in its entirety and was 100% in our study. Localization of nonpalpable lesions of the breast remains a useful procedure for diagnosis of suspicious lesions. The choice of the imaging technique depends on the characteristics of the lesion under study.

  13. Comparison of mouse mammary gland imaging techniques and applications: Reflectance confocal microscopy, GFP Imaging, and ultrasound

    PubMed Central

    Tilli, Maddalena T; Parrish, Angela R; Cotarla, Ion; Jones, Laundette P; Johnson, Michael D; Furth, Priscilla A

    2008-01-01

    Background Genetically engineered mouse models of mammary gland cancer enable the in vivo study of molecular mechanisms and signaling during development and cancer pathophysiology. However, traditional whole mount and histological imaging modalities are only applicable to non-viable tissue. Methods We evaluated three techniques that can be quickly applied to living tissue for imaging normal and cancerous mammary gland: reflectance confocal microscopy, green fluorescent protein imaging, and ultrasound imaging. Results In the current study, reflectance confocal imaging offered the highest resolution and was used to optically section mammary ductal structures in the whole mammary gland. Glands remained viable in mammary gland whole organ culture when 1% acetic acid was used as a contrast agent. Our application of using green fluorescent protein expressing transgenic mice in our study allowed for whole mammary gland ductal structures imaging and enabled straightforward serial imaging of mammary gland ducts in whole organ culture to visualize the growth and differentiation process. Ultrasound imaging showed the lowest resolution. However, ultrasound was able to detect mammary preneoplastic lesions 0.2 mm in size and was used to follow cancer growth with serial imaging in living mice. Conclusion In conclusion, each technique enabled serial imaging of living mammary tissue and visualization of growth and development, quickly and with minimal tissue preparation. The use of the higher resolution reflectance confocal and green fluorescent protein imaging techniques and lower resolution ultrasound were complementary. PMID:18215290

  14. An Integrated Backscatter Ultrasound Technique for the Detection of Coronary and Carotid Atherosclerotic Lesions

    PubMed Central

    Kawasaki, Masanori

    2015-01-01

    The instability of carotid and coronary plaques has been reported to be associated with acute coronary syndrome, strokes and other cerebrovascular events. Therefore, recognition of the tissue characteristics of carotid and coronary plaques is important to understand and prevent coronary and cerebral artery disease. Recently, an ultrasound integrated backscatter (IB) technique has been developed. The ultrasound IB power ratio is a function of the difference in acoustic characteristic impedance between the medium and target tissue, and the acoustic characteristic impedance is determined by the density of tissue multiplied by the speed of sound. This concept allows for tissue characterization of carotid and coronary plaques for risk stratification of patients with coronary and cerebral artery disease. Two- and three-dimensional IB color-coded maps for the evaluation of tissue components consist of four major components: fibrous, dense fibrosis, lipid pool and calcification. Although several ultrasound techniques using special mathematical algorithms have been reported, a growing body of literature has shown the reliability and usefulness of the IB technique for the tissue characterization of carotid and coronary plaques. This review summarizes concepts, experimental procedures, image reliability and the application of the IB technique. Furthermore, the IB technique is compared with other techniques. PMID:25574937

  15. An integrated backscatter ultrasound technique for the detection of coronary and carotid atherosclerotic lesions.

    PubMed

    Kawasaki, Masanori

    2015-01-07

    The instability of carotid and coronary plaques has been reported to be associated with acute coronary syndrome, strokes and other cerebrovascular events. Therefore, recognition of the tissue characteristics of carotid and coronary plaques is important to understand and prevent coronary and cerebral artery disease. Recently, an ultrasound integrated backscatter (IB) technique has been developed. The ultrasound IB power ratio is a function of the difference in acoustic characteristic impedance between the medium and target tissue, and the acoustic characteristic impedance is determined by the density of tissue multiplied by the speed of sound. This concept allows for tissue characterization of carotid and coronary plaques for risk stratification of patients with coronary and cerebral artery disease. Two- and three-dimensional IB color-coded maps for the evaluation of tissue components consist of four major components: fibrous, dense fibrosis, lipid pool and calcification. Although several ultrasound techniques using special mathematical algorithms have been reported, a growing body of literature has shown the reliability and usefulness of the IB technique for the tissue characterization of carotid and coronary plaques. This review summarizes concepts, experimental procedures, image reliability and the application of the IB technique. Furthermore, the IB technique is compared with other techniques.

  16. Understanding modern breast reduction techniques with a simplified approach.

    PubMed

    Andrades, Patricio; Prado, Arturo

    2008-11-01

    The purpose of this study was to analyse the geometrical principles of breast reduction, to propose a classification of reduction mammaplasty techniques and to show a simplified approach based on the authors experience. A thorough analysis of the geometrical differences between the normal and enlarged breast was performed. As a result of this analysis, the concept of separate management of the skin and gland for breast reduction was used as a method to classify the different techniques. Some aspects of technique selection and the authors' preferences are also discussed. The four geometric differences between the normal and enlarged breast are: vertical excess, broadened base, horizontal excess and a descended nipple-areola complex. All breast reduction techniques use a specific pedicle and a separate skin incision pattern, so they should be named after the scar and pedicle used. Technique selection must consider the degree of hypertrophy and ptosis, the skin and gland quality, the patient's requirements, and the surgeon's experience and preferences. Some clinical examples are provided. The comprehension of basic breast geometry, a universal language for communication and a simple algorithm to approach the breast reduction patient are valuable tools, particularly for the surgeon who is becoming acquainted with reduction mammaplasty procedures.

  17. Evaluation of macrozone dimensions by ultrasound and EBSD techniques

    SciTech Connect

    Moreau, Andre; Toubal, Lotfi; Bocher, Philippe; Humbert, Michel; Uta, Elena; Gey, Nathalie

    2013-01-15

    Titanium alloys are known to have texture heterogeneities, i.e. regions much larger than the grain dimensions, where the local orientation distribution of the grains differs from one region to the next. The electron backscattering diffraction (EBSD) technique is the method of choice to characterize these macro regions, which are called macrozones. Qualitatively, the images obtained by EBSD show that these macrozones may be larger or smaller, elongated or equiaxed. However, often no well-defined boundaries are observed between the macrozones and it is very hard to obtain objective and quantitative estimates of the macrozone dimensions from these data. In the present work, we present a novel, non-destructive ultrasonic technique that provides objective and quantitative characteristic dimensions of the macrozones. The obtained dimensions are based on the spatial autocorrelation function of fluctuations in the sound velocity. Thus, a pragmatic definition of macrozone dimensions naturally arises from the ultrasonic measurement. This paper has three objectives: 1) to disclose the novel, non-destructive ultrasonic technique to measure macrozone dimensions, 2) to propose a quantitative and objective definition of macrozone dimensions adapted to and arising from the ultrasonic measurement, and which is also applicable to the orientation data obtained by EBSD, and 3) to compare the macrozone dimensions obtained using the two techniques on two samples of the near-alpha titanium alloy IMI834. In addition, it was observed that macrozones may present a semi-periodical arrangement. - Highlights: Black-Right-Pointing-Pointer Discloses a novel, ultrasonic NDT technique to measure macrozone dimensions Black-Right-Pointing-Pointer Proposes a quantitative and objective definition of macrozone dimensions Black-Right-Pointing-Pointer Compares macrozone dimensions obtained using EBSD and ultrasonics on 2 Ti samples Black-Right-Pointing-Pointer Observes that macrozones may have a semi

  18. The Political Persuaders; The Techniques of Modern Election Campaigns.

    ERIC Educational Resources Information Center

    Nimmo, Dan

    Over the last 20 years, a successful election campaign has come to depend in large part on successful use of the broadcast media. As a result, media experts are part of most politicians' teams, and their strategies help determine the results of the election. Usually, themes or "images" are more important than issues. The techniques of mass…

  19. In vivo evaluation of drug delivery after ultrasound application: A new use for the photoacoustic technique

    NASA Astrophysics Data System (ADS)

    Barja, P. R.; Acosta-Avalos, D.; Rompe, P. C. B.; Dos Anjos, F. H.; Marciano, F. R.; da Silva, M. D.

    2005-06-01

    Ultrasound application is a therapeutical resource widely employed in physiotherapy. One of its applications is the phonophoresis, a technique in which the ultrasound radiation is utilized to deliver drugs through the skin to soft tissues. The proposal of our study was to employ the Photoacoustic Technique to evaluate the efficacy of such treatment, analyzing if phonophoresis could enhance drug delivery through skin when compared to the more traditional method of manual massage. The configuration of the system employed was such that it was possible to perform in vivo measurements, which is a pre-requisite for this kind of study. The changes observed in the photoacoustic signal amplitude after each form of drug application were attributed to changes in the thermal effusivity of the system, due to penetration of the drug. The technique was able to detect differences in drug delivery between the specified physiotherapy treatments, indicating that phonophoresis enhances drug absorption by tissue.

  20. Analgesic Efficacy and Technique of Ultrasound-Guided Suprascapular Nerve Catheters after Shoulder Arthroscopy

    PubMed Central

    Elsharkawy, Hesham A.; Abd-Elsayed, Alaa A.; Cummings, Kenneth C.; Soliman, Loran Mounir

    2014-01-01

    Background Conventional approaches to brachial plexus blocks may not cover the suprascapular nerve. Accordingly, after shoulder arthroscopy, sensation from the posterior part of the shoulder is commonly spared. Most previous research involving suprascapular nerve blocks described single-injection techniques. However, with the widespread availability and fairly reasonable cost of disposable infusion pumps, continuous catheter techniques provide a more appealing method of prolonging postoperative analgesia. Case Report We describe 2 patients who were successfully treated with ultrasound-guided continuous suprascapular nerve catheters. With the patient seated, a high-frequency linear ultrasound probe was used. Both patients experienced excellent pain relief without complications. Conclusion Continuous suprascapular catheter techniques provide good pain relief and improve postoperative analgesia after shoulder arthroscopy. PMID:24940138

  1. Modernized Techniques for Dealing with Quality Data and Derived Products

    NASA Astrophysics Data System (ADS)

    Neiswender, C.; Miller, S. P.; Clark, D.

    2008-12-01

    "I just want a picture of the ocean floor in this area" is expressed all too often by researchers, educators, and students in the marine geosciences. As more sophisticated systems are developed to handle data collection and processing, the demand for quality data, and standardized products continues to grow. Data management is an invisible bridge between science and researchers/educators. The SIOExplorer digital library presents more than 50 years of ocean-going research. Prior to publication, all data is checked for quality using standardized criterion developed for each data stream. Despite the evolution of data formats and processing systems, SIOExplorer continues to present derived products in well- established formats. Standardized products are published for each cruise, and include a cruise report, MGD77 merged data, multi-beam flipbook, and underway profiles. Creation of these products is made possible by processing scripts, which continue to change with ever-evolving data formats. We continue to explore the potential of database-enabled creation of standardized products, such as the metadata-rich MGD77 header file. Database-enabled, automated processing produces standards-compliant metadata for each data and derived product. Metadata facilitates discovery and interpretation of published products. This descriptive information is stored both in an ASCII file, and a searchable digital library database. SIOExplorer's underlying technology allows focused search and retrieval of data and products. For example, users can initiate a search of only multi-beam data, which includes data-specific parameters. This customization is made possible with a synthesis of database, XML, and PHP technology. The combination of standardized products and digital library technology puts quality data and derived products in the hands of scientists. Interoperable systems enable distribution these published resources using technology such as web services. By developing modernized

  2. Could modern forecasting techniques have predicted the blizzard of 1888?

    NASA Technical Reports Server (NTRS)

    Kocin, Paul J.

    1988-01-01

    Surface meteorological data for March 1888, which were collected at 170 stations across the U.S. three times a day, are combined with ship reports to construct a surface weather analysis for the blizzard of 1888. Surface weather charts are constructed to determine the ability of current forecasting techniques to predict the blizzard. The evolution of the storm is described in detail and current methods for treating a storm of similar intensity are discussed.

  3. Ultrasound-guided synovial Tru-cut biopsy: indications, technique, and outcome in 111 cases.

    PubMed

    Sitt, Jacqueline C M; Griffith, James F; Lai, Fernand M; Hui, Mamie; Chiu, K H; Lee, Ryan K L; Ng, Alex W H; Leung, Jason

    2017-05-01

    To investigate the diagnostic performance of ultrasound-guided synovial biopsy. Clinical notes, pathology and microbiology reports, ultrasound and other imaging studies of 100 patients who underwent 111 ultrasound-guided synovial biopsies were reviewed. Biopsies were compared with the final clinical diagnosis established after synovectomy (n = 43) or clinical/imaging follow-up (n = 57) (mean 30 months). Other than a single vasovagal episode, no complication of synovial biopsy was encountered. One hundred and seven (96 %) of the 111 biopsies yielded synovium histologically. Pathology ± microbiology findings for these 107 conclusive biopsies comprised synovial tumour (n = 30, 28 %), synovial infection (n = 18, 17 %), synovial inflammation (n = 45, 42 %), including gouty arthritis (n = 3), and no abnormality (n = 14, 13 %). The accuracy, sensitivity, and specificity of synovial biopsy was 99 %, 97 %, and 100 % for synovial tumour; 100 %, 100 %, and 100 % for native joint infection; and 78 %, 45 %, and 100 % for prosthetic joint infection. False-negative synovial biopsy did not seem to be related to antibiotic therapy. Ultrasound-guided Tru-cut synovial biopsy is a safe and reliable technique with a high diagnostic yield for diagnosing synovial tumour and also, most likely, for joint infection. Regarding joint infection, synovial biopsy of native joints seems to have a higher diagnostic yield than that for infected prosthetic joints. • Ultrasound-guided Tru-cut synovial biopsy has high accuracy (99 %) for diagnosing synovial tumour. • It has good accuracy, sensitivity, and high specificity for diagnosis of joint infection. • Synovial biopsy of native joints works better than biopsy of prosthetic joints. • A negative synovial biopsy culture from a native joint largely excludes septic arthritis. • Ultrasound-guided Tru-cut synovial biopsy is a safe and well-tolerated procedure.

  4. Modern Micro and Nanoparticle-Based Imaging Techniques

    PubMed Central

    Ryvolova, Marketa; Chomoucka, Jana; Drbohlavova, Jana; Kopel, Pavel; Babula, Petr; Hynek, David; Adam, Vojtech; Eckschlager, Tomas; Hubalek, Jaromir; Stiborova, Marie; Kaiser, Jozef; Kizek, Rene

    2012-01-01

    The requirements for early diagnostics as well as effective treatment of insidious diseases such as cancer constantly increase the pressure on development of efficient and reliable methods for targeted drug/gene delivery as well as imaging of the treatment success/failure. One of the most recent approaches covering both the drug delivery as well as the imaging aspects is benefitting from the unique properties of nanomaterials. Therefore a new field called nanomedicine is attracting continuously growing attention. Nanoparticles, including fluorescent semiconductor nanocrystals (quantum dots) and magnetic nanoparticles, have proven their excellent properties for in vivo imaging techniques in a number of modalities such as magnetic resonance and fluorescence imaging, respectively. In this article, we review the main properties and applications of nanoparticles in various in vitro imaging techniques, including microscopy and/or laser breakdown spectroscopy and in vivo methods such as magnetic resonance imaging and/or fluorescence-based imaging. Moreover the advantages of the drug delivery performed by nanocarriers such as iron oxides, gold, biodegradable polymers, dendrimers, lipid based carriers such as liposomes or micelles are also highlighted. PMID:23202187

  5. Knuckle technique guided by intravascular ultrasound for in-stent restenosis occlusion treatment

    PubMed Central

    Tasic, Mladen; Jagic, Nikola; Miloradovic, Vladimir; Nikolic, Dusan

    2015-01-01

    One of the rarest lesions is in-stent restenosis chronic total occlusion (CTO). Limited data suggest that the treatment success rate is dependent on the possibility to cross into the lumen of an occluded stent, and the decision about what technique to use varies by operator preference. The knuckle technique is used to create a deliberate dissection plane in various CTO techniques. A guide wire is pushed until a complex loop is formed and advanced through the lesion. In this report we present a case where a knuckle wire guided by intravascular ultrasound control is used to penetrate the distal cap in an in-stent restenosis CTO lesion. PMID:25848374

  6. Quantitative ultrasound techniques for the assessment of osteoporosis: expert agreement on current status. The International Quantitative Ultrasound Consensus Group.

    PubMed

    Glüer, C C

    1997-08-01

    Quantitative ultrasound (QUS) methods have been introduced in recent years for the assessment of skeletal status in osteoporosis. The performance of QUS techniques has been evaluated in a large number of studies. Reviewing existing knowledge, an international expert panel formulated the following consensus regarding the current status of this technology. To date, evidence supports the use of QUS techniques for the assessment of fracture risk in elderly women. This has been best established for water-based calcaneal QUS systems. Future studies should include the predictive validity of other QUS systems. Additional clinical applications of QUS, specifically the assessment of rates of change for monitoring disease progression or response to treatment, require further investigation. Its low cost and portability make QUS an attractive technology for assessing risk of fractures in larger populations than may be suitable or feasible for bone densitometry. Additional investigations that assess innovative QUS techniques in well defined research settings are important to determine and utilize the full potential of this technology for the benefit of early detection and monitoring of osteoporosis.

  7. Modern Techniques in Acoustical Signal and Image Processing

    SciTech Connect

    Candy, J V

    2002-04-04

    Acoustical signal processing problems can lead to some complex and intricate techniques to extract the desired information from noisy, sometimes inadequate, measurements. The challenge is to formulate a meaningful strategy that is aimed at performing the processing required even in the face of uncertainties. This strategy can be as simple as a transformation of the measured data to another domain for analysis or as complex as embedding a full-scale propagation model into the processor. The aims of both approaches are the same--to extract the desired information and reject the extraneous, that is, develop a signal processing scheme to achieve this goal. In this paper, we briefly discuss this underlying philosophy from a ''bottom-up'' approach enabling the problem to dictate the solution rather than visa-versa.

  8. Bypassing absorbing objects in focused ultrasound using computer generated holographic technique.

    PubMed

    Hertzberg, Y; Navon, G

    2011-12-01

    Focused ultrasound (FUS) technology is based on heating a small volume of tissue, while keeping the temperature outside the focus region with minimal heating only. Several FUS applications, such as brain and liver, suffer from the existence of ultrasound absorbers in the acoustic path between the transducer and the focus. These absorbers are a potential risk for the FUS therapy since they might cause to unwanted heating outside the focus region. An acoustic simulation based solution for reducing absorbers' heating is proposed, demonstrated, and compared to the standard geometrical solution. The proposed solution uses 3D continuous acoustic holograms, generated by the Gerchberg-Saxton (GS) algorithm, which are described and demonstrated for the first time using ultrasound planar phased-array transducer. Holograms were generated using the iterative GS algorithm and fast Fourier transform (FFT) acoustic simulation. The performances of the holograms are demonstrated by temperature elevation images of the absorber, acquired by GE 1.5T MRI scanner equipped with InSightec FUS planar phased-array transducer built out of 986 transmitting elements. The acoustic holographic technology is demonstrated numerically and experimentally using the three letters patterns, "T," "A," and "U," which were manually built into 1 × 1 cm masks to represent the requested target fields. 3D holograms of a focused ultrasound field with a hole in intensity at the absorber region were generated and compared to the standard geometrical solution. The proposed holographic solution results in 76% reduction of heating on absorber, while keeping similar heating at the focus. In the present work we show for the first time the generation of efficient and uniform continuous ultrasound holograms in 3D. We use the holographic technology to generate a FUS beams that bypasses an absorber in the acoustic path to reduce unnecessary heating and potential clinical risk. The developed technique is superior

  9. Validation of ultrasound techniques applied to body fat measurement. A comparison between ultrasound techniques, air displacement plethysmography and bioelectrical impedance vs. dual-energy X-ray absorptiometry.

    PubMed

    Pineau, Jean-Claude; Guihard-Costa, Anne-Marie; Bocquet, Michel

    2007-01-01

    To evaluate the accuracy of body fat percentage (BF%) estimates from a portable, non-traumatizing ultrasound device with high accuracy and reliability compared to dual-energy X-ray absorptiometry (DEXA), the reference technique. Cross-validation between ultrasound technique (UT), DEXA, air displacement plethysmography (ADP) and bioelectrical impedance (BIA) was developed in the study. A total of 89 healthy subjects (41 women, 48 men), aged 48.4 +/- 17.7 (mean +/- SD), with Body mass index (28.5 +/- 7.7 kg/m(2)) and body fat DEXA (29.6 +/- 10.8 kg) participated. BF% was measured using an UT associated with anthropometric parameters and simultaneously, with the DEXA reference technique, BIA and ADP. UT estimates of BF% were better correlated with those of DEXA in both males and females (r = 0.98, SEE = 2.0) than with ADP (r = 0.94, SEE = 3.7) or BIA (r = 0.92, SEE = 4.4). The UT in both genders was better (TE = 1.0) than BIA (TE = 2.6) and ADP (TE = 3.0). The 95% limits of agreement were also better for the UT (-2%; 2%) than with BIA (-5.1%; 4.9%) and ADP (-6.3%; 5.3%). The limits of agreement with BIA and ADP are unacceptably high compared to a DEXA measure criterion. The use of a new portable device based on a UT produced a very accurate BF% estimate in relation to the DEXA reference technique. (c) 2007 S. Karger AG, Basel.

  10. Modern integral equation techniques for quantum reactive scattering theory

    SciTech Connect

    Auerbach, Scott Michael

    1993-11-01

    Rigorous calculations of cross sections and rate constants for elementary gas phase chemical reactions are performed for comparison with experiment, to ensure that our picture of the chemical reaction is complete. We focus on the H/D+H2 → H2/DH + H reaction, and use the time independent integral equation technique in quantum reactive scattering theory. We examine the sensitivity of H+H2 state resolved integral cross sections σ{sub v'j',vj}(E) for the transitions (v = 0,j = 0) to (v'} = 1,j' = 1,3), to the difference between the Liu-Siegbahn-Truhlar-Horowitz (LSTH) and double many body expansion (DMBE) ab initio potential energy surfaces (PES). This sensitivity analysis is performed to determine the origin of a large discrepancy between experimental cross sections with sharply peaked energy dependence and theoretical ones with smooth energy dependence. We find that the LSTH and DMBE PESs give virtually identical cross sections, which lends credence to the theoretical energy dependence.

  11. Transrectal ultrasoundTechniques and outcomes in the management of intestinal endometriosis

    PubMed Central

    Rossini, Lucio G.B.; Ribeiro, Paulo A.A.G.; Rodrigues, Francisco C.M.; Filippi, Sheila S.; Zago, Rodrigo de R.; Schneider, Nutianne C.; Okawa, Luciano; Klug, Wilmar A.

    2012-01-01

    The widespread use of endoscopic ultrasound has facilitated the evaluation of subepithelial and surrounding lesions of the gastrointestinal tract. Deep pelvic endometriosis, with or without infiltration of the intestinal wall, is a frequent disease that can be observed in women in their fertile age. Patients of this disease may present nonspecific signs and symptoms or be completely asymptomatic. Laparoscopic surgical resection of endometriotic lesions is the treatment of choice in symptomatic patients. An accurate preoperative evaluation is indispensable for therapeutic decisions mainly in the suspicion of intestinal wall and/or urinary tract infiltration, and also in cases where we need to establish histological diagnosis or to rule out malignant disease. Diagnostic tools, including transrectal ultrasound, magnetic resonance image, transvaginal ultrasound, barium enema, and colonoscopy, play significant roles in determining the presence, depth, histology, and other relevant data about the extension of the disease. Diagnostic algorithm depends on the clinical presentation, the expertise of the medical team, and the technology available at each institution. This article reviews and discusses relevant clinical points in endometriosis, including techniques and outcomes of the study of the disease through transrectal ultrasound and fine-needle aspiration. PMID:24949332

  12. Visualization of ultrasound induced cavitation bubbles using the synchrotron x-ray Analyzer Based Imaging technique.

    PubMed

    Izadifar, Zahra; Belev, George; Izadifar, Mohammad; Izadifar, Zohreh; Chapman, Dean

    2014-12-07

    Observing cavitation bubbles deep within tissue is very difficult. The development of a method for probing cavitation, irrespective of its location in tissues, would improve the efficiency and application of ultrasound in the clinic. A synchrotron x-ray imaging technique, which is capable of detecting cavitation bubbles induced in water by a sonochemistry system, is reported here; this could possibly be extended to the study of therapeutic ultrasound in tissues. The two different x-ray imaging techniques of Analyzer Based Imaging (ABI) and phase contrast imaging (PCI) were examined in order to detect ultrasound induced cavitation bubbles. Cavitation was not observed by PCI, however it was detectable with ABI. Acoustic cavitation was imaged at six different acoustic power levels and six different locations through the acoustic beam in water at a fixed power level. The results indicate the potential utility of this technique for cavitation studies in tissues, but it is time consuming. This may be improved by optimizing the imaging method.

  13. Comparison of a novel real-time SonixGPS needle-tracking ultrasound technique with traditional ultrasound for vascular access in a phantom gel model.

    PubMed

    Kopac, Daniel S; Chen, Jerry; Tang, Raymond; Sawka, Andrew; Vaghadia, Himat

    2013-09-01

    Ultrasound-guided percutaneous vascular access for endovascular procedures is well established in surgical practice. Despite this, rates of complications from venous and arterial access procedures remain a significant cause of morbidity. We hypothesized that the use of a new technique of vascular access using an ultrasound with a novel needle-guidance positioning system (GPS) would lead to improved success rates of vascular puncture for both in-plane and out-of-plane techniques compared with traditional ultrasound. A prospective, randomized crossover study of medical students from all years of medical school was conducted using a phantom gel model. Each medical student performed three ultrasound-guided punctures with each of the four modalities (in-plane no GPS, in-plane with GPS, out-of-plane no GPS, out-of-plane with GPS) for a total of 12 attempts. The success or failure was judged by the ability to aspirate a simulated blood solution from the model. The time to successful puncture was also recorded. A poststudy validated NASA Task Load Index workload questionnaire was conducted to assess the student's perceptions of the two different techniques. A total of 30 students completed the study. There was no significant difference seen in the mean times of vascular access for each of the modalities. Higher success rates for vascular access using the GPS for both the in-plane (94% vs 91%) and the out-of-plane (86% vs 70%) views were observed; however, this was not statistically significant. The students perceived the mental demand (median 12.0 vs 14.00; P = .035) and effort to be lower (mean 11.25 vs 14.00; P = .044) as well as the performance to be higher (mean 15.50 vs 14.00; P = .041) for the GPS vs the traditional ultrasound-guided technique. Students also perceived their ability to access vessels increased with the aid of the GPS (7.00 vs 6.50; P = .007). The majority of students expressed a preference for GPS (26/30, 87%) as opposed to the traditional counterpart

  14. New endoscopic ultrasound techniques for digestive tract diseases: A comprehensive review

    PubMed Central

    Meng, Fan-Sheng; Zhang, Zhao-Hong; Ji, Feng

    2015-01-01

    Endoscopic ultrasound (EUS) is one of the most important modalities for the diagnosis of digestive tract diseases. EUS has been evolving ever since it was introduced. New techniques such as elastography and contrast enhancement have emerged, increasing the accuracy, sensitivity and specificity of EUS for the diagnosis of digestive tract diseases including pancreatic masses and lymphadenopathy. EUS-elastography evaluates tissue elasticity and therefore, can be used to differentiate various lesions. Contrast-enhanced EUS can distinguish benign from malignant pancreatic lesions and lymphadenopathy using the intravenous injection of contrast agents. This review discusses the principles and types of these new techniques, as well as their clinical applications and limitations. PMID:25944994

  15. Comparison of ultrasound and optical coherence tomography techniques for evaluation of integrity of spontaneously repaired horse cartilage.

    PubMed

    Virén, T; Huang, Y P; Saarakkala, S; Pulkkinen, H; Tiitu, V; Linjama, A; Kiviranta, I; Lammi, M J; Brünott, A; Brommer, H; Van Weeren, R; Brama, P A J; Zheng, Y P; Jurvelin, J S; Töyräs, J

    2012-04-01

    The aim of this study was to compare sensitivity of ultrasound and optical coherence tomography (OCT) techniques for the evaluation of the integrity of spontaneously repaired horse cartilage. Articular surfaces of horse intercarpal joints, featuring both intact tissue and spontaneously healed chondral or osteochondral defects, were imaged ex vivo with arthroscopic ultrasound and laboratory OCT devices. Quantitative ultrasound (integrated reflection coefficient (IRC), apparent integrated backscattering coefficient (AIB) and ultrasound roughness index (URI)) and optical parameters (optical reflection coefficient (ORC), optical roughness index (ORI) and optical backscattering (OBS)) were determined and compared with histological integrity and mechanical properties of the tissue. Spontaneously healed tissue could be quantitatively discerned from the intact tissue with ultrasound and OCT techniques. Furthermore, several significant correlations (p < 0.05) were detected between ultrasound and OCT parameters. Superior resolution of OCT provided a more accurate measurement of cartilage surface roughness, while the ultrasound backscattering from the inner structures of the cartilage matched better with the histological findings. Since the techniques were found to be complementary to each other, dual modality imaging techniques could provide a useful tool for the arthroscopic evaluation of the integrity of articular cartilage.

  16. Advantages in using multi-frequency driving ultrasound for optimizing echo particle image velocimetry techniques.

    PubMed

    Zheng, Hairong; Mukdadi, Osama; Hertzberg, Jean; Shandas, Robin

    2004-01-01

    We have recently developed an ultrasound based velocimetry technique, termed echo particle image velocimetry (echo PIV). This method takes advantage of the non-linear backscatter characteristics of ultrasound contrast microbubbles when exposed to certain ultrasonic field. Preliminary in vitro, animal and clinical studies have shown significant promise of this method for measuring multiple velocity components with good temporal and spatial resolution. However, there is still difficulty in maximizing the non-linearity of bubble backscatter using conventional Gaussian-pulse excitation techniques because significant harmonic components may not be produced at modest pressure amplitudes and the higher incident pressure amplitudes required to induce non-linear behavior may cause bubble destruction. We present here a potential solution to this problem through the use of multi-frequency excitation. A rectangular pulse with multiple harmonics is used to drive the bubble. The backscatter process is studied through a modified Rayleigh-Plesset equation. Results show that the rectangular wave is effective in improving the visibility of microbubbles with ultrasound backscattered efficiency significantly higher than the widely used Gaussian waveform. Use of rectangular pulses with 4 and 2 harmonics showed no significant difference in bubble backscatter behavior, indicating that a two-frequency excitation may be sufficient to induce non-linear behavior of the microbubbles practically at modest incident pressures.

  17. Development of a High-Throughput Ultrasound Technique for the Analysis of Tissue Engineering Constructs.

    PubMed

    Stukel, Jessica M; Goss, Monika; Zhou, Haoyan; Zhou, Wenda; Willits, Rebecca Kuntz; Exner, Agata A

    2016-03-01

    Development of hydrogel-based tissue engineering constructs is growing at a rapid rate, yet translation to patient use has been sluggish. Years of costly preclinical tests are required to predict clinical performance and safety of these devices. The tests are invasive, destructive to the samples and, in many cases, are not representative of the ultimate in vivo scenario. Biomedical imaging has the potential to facilitate biomaterial development by enabling longitudinal noninvasive device characterization directly in situ. Among the various available imaging modalities, ultrasound stands out as an excellent candidate due to low cost, wide availability, and a favorable safety profile. The overall goal of this work was to demonstrate the utility of clinical ultrasound in longitudinal characterization of 3D hydrogel matrices supporting cell growth. Specifically, we developed a quantitative technique using clinical B-mode ultrasound to differentiate collagen content and fibroblast density within poly(ethylene glycol) (PEG) hydrogels and validated it in an in vitro phantom environment. By manipulating the hydrogel gelation, differences in ultrasound signal intensity were found between gels with collagen fibers and those with non-fiber forming collagen, indicating that the technique was sensitive to the configuration of the protein. At a collagen density of 2.5 mg/mL collagen, fiber forming collagen had a significantly increased signal intensity of 14.90 ± 2.58 × 10(-5) a.u. compared to non-fiber forming intensity at 2.74 ± 0.36 × 10(-5) a.u. Additionally, differences in intensity were found between living and fixed fibroblasts, with an increased signal intensity detected in living cells (5.00 ± 0.80 × 10(-5) a.u. in 1 day live cells compared to 2.26 ± 0.39 × 10(-5) a.u.in fixed cells at a concentration of 1 × 10(6) cells/mL in gels containing collagen). Overall, there was a linear correlation >0.90 for ultrasound intensity with increasing

  18. Development of a High-Throughput Ultrasound Technique for the Analysis of Tissue Engineering Constructs

    PubMed Central

    Stukel, Jessica; Goss, Monika; Zhou, Haoyan; Zhou, Wenda; Willits, Rebecca; Exner, Agata A.

    2015-01-01

    Development of hydrogel-based tissue engineering constructs is growing at a rapid rate, yet translation to patient use has been sluggish. Years of costly preclinical tests are required to predict clinical performance and safety of these devices. The tests are invasive, destructive to the samples and, in many cases, are not representative of the ultimate in vivo scenario. Biomedical imaging has the potential to facilitate biomaterial development by enabling longitudinal noninvasive device characterization directly in situ. Among the various available imaging modalities, ultrasound stands out as an excellent candidate due to low cost, wide availability, and a favorable safety profile. The overall goal of this work was to demonstrate the utility of clinical ultrasound in longitudinal characterization of 3D hydrogel matrices supporting cell growth. Specifically, we developed a quantitative technique using clinical B-mode ultrasound to differentiate collagen content and fibroblast density within poly(ethylene glycol) (PEG) hydrogels and validated it in an in vitro phantom environment. By manipulating the hydrogel gelation, differences in ultrasound signal intensity were found between gels with collagen fibers and those with non-fiber forming collagen, indicating that the technique was sensitive to the configuration of the protein. At a collagen density of 2.5 mg/mL collagen, fiber forming collagen had a significantly increased signal intensity of 14.90± 2.58*10−5 a.u. compared to non-fiber forming intensity at 2.74± 0.36*10−5 a.u. Additionally, differences in intensity were found between living and fixed fibroblasts, with an increased signal intensity detected in living cells (5 ± 0.8*10−5 a.u. in 1 day live cells compared to 2.26 ± 0.39*10−5 a.u. in fixed cells at a concentration of 1*106 cells/mL in gels containing collagen). Overall, there was a linear correlation >0.90 for ultrasound intensity with increasing cell density. Results demonstrate the

  19. Endoscopic ultrasound-guided techniques for diagnosing pancreatic mass lesions: Can we do better?

    PubMed Central

    Storm, Andrew C; Lee, Linda S

    2016-01-01

    The diagnostic approach to a possible pancreatic mass lesion relies first upon various non-invasive imaging modalities, including computed tomography, ultrasound, and magnetic resonance imaging techniques. Once a suspect lesion has been identified, tissue acquisition for characterization of the lesion is often paramount in developing an individualized therapeutic approach. Given the high prevalence and mortality associated with pancreatic cancer, an ideal approach to diagnosing pancreatic mass lesions would be safe, highly sensitive, and reproducible across various practice settings. Tools, in addition to radiologic imaging, currently employed in the initial evaluation of a patient with a pancreatic mass lesion include serum tumor markers, endoscopic retrograde cholangiopancreatography, and endoscopic ultrasound-guided fine needle aspiration (EUS-FNA). EUS-FNA has grown to become the gold standard in tissue diagnosis of pancreatic lesions. PMID:27818584

  20. Automatic Cataract Classification based on Ultrasound Technique Using Machine Learning: A comparative Study

    NASA Astrophysics Data System (ADS)

    Caxinha, Miguel; Velte, Elena; Santos, Mário; Perdigão, Fernando; Amaro, João; Gomes, Marco; Santos, Jaime

    This paper addresses the use of computer-aided diagnosis (CAD) system for the cataract classification based on ultrasound technique. Ultrasound A-scan signals were acquired in 220 porcine lenses. B-mode and Nakagami images were constructed. Ninety-seven parameters were extracted from acoustical, spectral and image textural analyses and were subjected to feature selection by Principal Component Analysis (PCA). Bayes, K Nearest-Neighbors (KNN), Fisher Linear Discriminant (FLD) and Support Vector Machine (SVM) classifiers were tested. The classification of healthy and cataractous lenses shows a good performance for the four classifiers (F-measure ≥92.68%) with SVM showing the highest performance (90.62%) for initial versus severe cataract classification.

  1. Modern modelling techniques are data hungry: a simulation study for predicting dichotomous endpoints.

    PubMed

    van der Ploeg, Tjeerd; Austin, Peter C; Steyerberg, Ewout W

    2014-12-22

    Modern modelling techniques may potentially provide more accurate predictions of binary outcomes than classical techniques. We aimed to study the predictive performance of different modelling techniques in relation to the effective sample size ("data hungriness"). We performed simulation studies based on three clinical cohorts: 1282 patients with head and neck cancer (with 46.9% 5 year survival), 1731 patients with traumatic brain injury (22.3% 6 month mortality) and 3181 patients with minor head injury (7.6% with CT scan abnormalities). We compared three relatively modern modelling techniques: support vector machines (SVM), neural nets (NN), and random forests (RF) and two classical techniques: logistic regression (LR) and classification and regression trees (CART). We created three large artificial databases with 20 fold, 10 fold and 6 fold replication of subjects, where we generated dichotomous outcomes according to different underlying models. We applied each modelling technique to increasingly larger development parts (100 repetitions). The area under the ROC-curve (AUC) indicated the performance of each model in the development part and in an independent validation part. Data hungriness was defined by plateauing of AUC and small optimism (difference between the mean apparent AUC and the mean validated AUC <0.01). We found that a stable AUC was reached by LR at approximately 20 to 50 events per variable, followed by CART, SVM, NN and RF models. Optimism decreased with increasing sample sizes and the same ranking of techniques. The RF, SVM and NN models showed instability and a high optimism even with >200 events per variable. Modern modelling techniques such as SVM, NN and RF may need over 10 times as many events per variable to achieve a stable AUC and a small optimism than classical modelling techniques such as LR. This implies that such modern techniques should only be used in medical prediction problems if very large data sets are available.

  2. Current role of modern radiotherapy techniques in the management of breast cancer

    PubMed Central

    Ozyigit, Gokhan; Gultekin, Melis

    2014-01-01

    Breast cancer is the most common type of malignancy in females. Advances in systemic therapies and radiotherapy (RT) provided long survival rates in breast cancer patients. RT has a major role in the management of breast cancer. During the past 15 years several developments took place in the field of imaging and irradiation techniques, intensity modulated RT, hypofractionation and partial-breast irradiation. Currently, improvements in the RT technology allow us a subsequent decrease in the treatment-related complications such as fibrosis and long-term cardiac toxicity while improving the loco-regional control rates and cosmetic results. Thus, it is crucial that modern radiotherapy techniques should be carried out with maximum care and efficiency. Several randomized trials provided evidence for the feasibility of modern radiotherapy techniques in the management of breast cancer. However, the role of modern radiotherapy techniques in the management of breast cancer will continue to be defined by the mature results of randomized trials. Current review will provide an up-to-date evidence based data on the role of modern radiotherapy techniques in the management of breast cancer. PMID:25114857

  3. Comparison of paravertebral blockade techniques with and without ultrasound guidance in calves.

    PubMed

    Re, Michela; Blanco-Murcia, Javier; Villaescusa, Alejandra; De Gaspar, Ignacio; de Segura, Ignacio A Gómez

    2016-11-01

    OBJECTIVE To compare the effectiveness of an ultrasound-guided paravertebral nerve blockade technique (UGPNB) with distal and proximal paravertebral nerve blockade techniques without ultrasound guidance (DPNB and PPNB, respectively) in calves. ANIMALS 4 calf cadavers and 7 healthy calves. PROCEDURES A suitable acoustic window was identified to facilitate access to the T13, L1, and L2 spinal nerves in cadavers and live calves. In cadavers, nerves were injected with dye under ultrasound guidance. In calves, the UGPNB, DPNB, and PPNB were performed in random order at 10-day intervals by injection of an anesthetic solution containing 2% lidocaine hydrochloride. Nociceptive withdrawal responses were assessed to determine the effects of the blockades. RESULTS In cadavers, nerve staining success rates (ie, ≥ 2-cm-long dye path) achieved with ultrasound guidance were 88% (T13 [ventral branch]), 75% (T13 and L1 [dorsal branches] and L1 and L2 [ventral branches]), and 38% (L2 [dorsal branch]). The nerves were each identified as a hyperechoic band in a longitudinal plane. In calves, the UGPNB, DPNB, and PPNB reduced the withdrawal response to the noxious stimulus, mainly in the dorsal-cranial, dorsal-caudal, and ventral-cranial areas of the flank. Overall, the UGPNB resulted in a better nociceptive cumulative score, administering only one half of the local anaesthetic dose, compared with findings for the DPNB and PPNB. However, time to perform the UGPNB was longer. CONCLUSIONS AND CLINICAL RELEVANCE The UGPNB evaluated may be an improved alternative to the DPNB and PPNB for provision of anesthesia for flank surgery in calves. However, effectiveness of the UGPNB should be evaluated in a clinical setting and in adult cattle.

  4. In Vivo Quantification of Flow Dynamics in Intracranial Aneurysms Using Intra-Operative Contrast-Specific Ultrasound and PIV Techniques

    NASA Astrophysics Data System (ADS)

    CantÓN, G.Á.}Dor

    2005-11-01

    The goal of this study is to assess in vivo the hemodynamics of intracranial aneurysms using ultrasound and Digital Particle Imaging Velocimetry (DPIV) techniques. An ultrasound machine, equipped with an intra-operative transducer, was used to visualize the flow features inside an aneurysm with the aid of microbubbles as ultrasound contrast agent. The ultrasound studies were done using a Phase Inversion technique. Operating in the Doppler mode, the flow velocities in the afferent and the downstream vascular segments as well as inside the aneurysm were recorded and assessed. We analyzed the ultrasound data sets with a DPIV technique using backscattered signals from the microbubbles. The spatial and temporal distribution of velocity, vorticity, and stress fields was measured. These quantities were also measured in an in vitro aneurysmal model using the DPIV system. Our study shows that an advanced contrast-specific ultrasound technique in combination with a DPIV technique can be used to quantify in real time the flow-mechanical patterns inside the aneurysm.

  5. A novel dehydration technique for carrot slices implementing ultrasound and vacuum drying methods.

    PubMed

    Chen, Zhi-Gang; Guo, Xiao-Yu; Wu, Tao

    2016-05-01

    A novel drying technique using a combination of ultrasound and vacuum dehydration was developed to shorten the drying time and improve the quality of carrot slices. Carrot slices were dried with ultrasonic vacuum (USV) drying and vacuum drying at 65 °C and 75 °C. The drying rate was significantly influenced by the drying techniques and temperatures. Compared with vacuum drying, USV drying resulted in a 41-53% decrease in the drying time. The drying time for the USV and vacuum drying techniques at 75 °C was determined to be 140 and 340 min for carrot slices, respectively. The rehydration potential, nutritional value (retention of β-carotene and ascorbic acid), color, and textural properties of USV-dried carrot slices are predominately better compared to vacuum-dried carrot slices. Moreover, lower energy consumption was used in the USV technique. The drying data (time versus moisture ratio) were successfully fitted to Wang and Singh model.

  6. Thyroid ultrasound

    PubMed Central

    Chaudhary, Vikas; Bano, Shahina

    2013-01-01

    Thyroid ultrasonography has established itself as a popular and useful tool in the evaluation and management of thyroid disorders. Advanced ultrasound techniques in thyroid imaging have not only fascinated the radiologists but also attracted the surgeons and endocrinologists who are using these techniques in their daily clinical and operative practice. This review provides an overview of indications for ultrasound in various thyroid diseases, describes characteristic ultrasound findings in these diseases, and illustrates major diagnostic pitfalls of thyroid ultrasound. PMID:23776892

  7. Consequences of modern anthropometric dimensions for radiographic techniques and patient radiation exposures.

    PubMed

    Shah, Chintan; Jones, A Kyle; Willis, Charles E

    2008-08-01

    Radiographic techniques are devised on the basis of anatomic dimensions. Inaccurate dimensions can cause radiographs to be exposed inappropriately and patient radiation exposures to be calculated incorrectly. The source of anatomic dimensions in common usage dates back to 1948. The objective of this study was to compare traditional and modern anthropometric data, use modern dimensions to estimate potential errors in patient exposure, and suggest modified technique guidelines. Anthropometry software was used to derive modern anatomic dimensions. Data from routine annual testing were analyzed to develop an x-ray generator output curve. Published tabulated data were used to determine the relationship between tissue half-value layer and kilovoltage. These relationships were used to estimate entrance skin exposure and create a provisional technique guide. While most anatomic regions were actually larger than previously indicated, some were similar, and a few were smaller. Accordingly, exposure estimates were higher, similar, or lower, depending on the anatomic region. Exposure estimates using modern dimensions for clinically significant regions of the trunk were higher than those calculated with traditional dimensions. Exposures of the postero-anterior chest, lateral chest, antero-posterior (AP) abdomen, male AP pelvis, and female AP pelvis were larger by 48%, 31%, 54%, 52%, and 112%, respectively. The dimensions of bony regions of the anatomy, such as the joints and skull, were unchanged. These findings are consistent with the idea that anatomic areas where fat is deposited are larger in the modern U.S. population than they were in previous years. Exposure techniques for manual radiography and calculations of patient dose for automatic exposure control radiography should be adjusted according to the modern dimensions. Population radiation exposure estimates calculated in national surveys should also be modified appropriately.

  8. Prospective Study Comparing Two Second-Look Ultrasound Techniques: Handheld Ultrasound and an Automated Breast Volume Scanner.

    PubMed

    Kim, Yoonsoo; Kang, Bong Joo; Kim, Sung Hun; Lee, Eun Jae

    2016-10-01

    The aim of this study was to compare the diagnostic performance of handheld ultrasound (US) and an automated breast volume scanner (ABVS) as second-look US techniques subsequent to preoperative breast magnetic resonance imaging (MRI). We prospectively enrolled patients with breast cancer who underwent handheld US and ABVS examinations as second-look US modalities for additional suspicious lesions found via preoperative breast MRI. We reviewed each second-look US modality independently and evaluated the detection rate of each modality. We then analyzed the correlation between the detection rate and the MRI factors (size, distance, and enhancement type). From March to September 2014, both types of second-look US examinations were performed on 40 patients with breast cancer who had 76 additional suspicious lesions detected via preoperative breast MRI. The detection rate of the ABVS was higher than that of handheld US for the second-look examination (94.7% versus 86.8%; P< .05). Among the 76 total lesions, 7 were only identified by the ABVS, 1 was only found by handheld US, and 3 were not detected by either the ABVS or handheld US. When we analyzed the correlation between the detection rate and MRI factors, the only meaningful factor was the enhancement type. The ability to detect a nonmass lesion was lower than the ability to detect a mass-type lesion (P < 0.05) for both the ABVS and handheld US. For a second-look US examination subsequent to preoperative breast MRI in patients with breast cancer, the ABVS is a more efficient modality than handheld US for preoperative evaluations. However, both techniques have limitations in detecting nonmass lesions.

  9. [Randomized prospective study of three different techniques for ultrasound-guided axillary brachial plexus block].

    PubMed

    Ferraro, Leonardo Henirque Cunha; Takeda, Alexandre; Sousa, Paulo César Castello Branco de; Mehlmann, Fernanda Moreira Gomes; Junior, Jorge Kiyoshi Mitsunaga; Falcão, Luiz Fernando Dos Reis

    2017-06-23

    Randomized prospective study comparing two perivascular techniques with the perineural technique for ultrasound-guided axillary brachial plexus block (US-ABPB). The primary objective was to verify if these perivascular techniques are noninferior to the perineural technique. 240 patients were randomized to receive the techniques: below the artery (BA), around the artery (AA) or perineural (PN). The anesthetic volume used was 40mL of 0.375% bupivacaine. All patients received a musculocutaneous nerve blockade with 10mL. In BA technique, 30mL were injected below the axillary artery. In AA technique, 7.5mL were injected at 4 points around the artery. In PN technique, the median, ulnar, and radial nerves were anesthetized with 10mL per nerve. Confidence interval analysis showed that the perivascular techniques studied were not inferior to the perineural technique. The time to perform the blockade was shorter for the BA technique (300.4±78.4sec, 396.5±117.1sec, 487.6±172.6sec, respectively). The PN technique showed a lower latency time (PN - 655.3±348.9sec; BA -1044±389.5sec; AA-932.9±314.5sec), and less total time for the procedure (PN-1132±395.8sec; BA -1346.2±413.4sec; AA 1329.5±344.4sec). TA technique had a higher incidence of vascular puncture (BA - 22.5%; AA - 16.3%; PN - 5%). The perivascular techniques are viable alternatives to perineural technique for US-ABPB. There is a higher incidence of vascular puncture associated with the BA technique. Copyright © 2017. Publicado por Elsevier Editora Ltda.

  10. Community to Classroom: Reflections on Community-Centered Pedagogy in Contemporary Modern Dance Technique

    ERIC Educational Resources Information Center

    Fitzgerald, Mary

    2017-01-01

    This article reflects on the ways in which socially engaged arts practices can contribute to reconceptualizing the contemporary modern dance technique class as a powerful site of social change. Specifically, the author considers how incorporating socially engaged practices into pedagogical models has the potential to foster responsible citizenship…

  11. Community to Classroom: Reflections on Community-Centered Pedagogy in Contemporary Modern Dance Technique

    ERIC Educational Resources Information Center

    Fitzgerald, Mary

    2017-01-01

    This article reflects on the ways in which socially engaged arts practices can contribute to reconceptualizing the contemporary modern dance technique class as a powerful site of social change. Specifically, the author considers how incorporating socially engaged practices into pedagogical models has the potential to foster responsible citizenship…

  12. Application of metabonomic analytical techniques in the modernization and toxicology research of traditional Chinese medicine

    PubMed Central

    Lao, Yong-Min; Jiang, Jian-Guo; Yan, Lu

    2009-01-01

    In the recent years, a wide range of metabonomic analytical techniques are widely used in the modern research of traditional Chinese medicine (TCM). At the same time, the international community has attached increasing importance to TCM toxicity problems. Thus, many studies have been implemented to investigate the toxicity mechanisms of TCM. Among these studies, many metabonomic-based methods have been implemented to facilitate TCM toxicity investigation. At present, the most prevailing methods for TCM toxicity research are mainly single analysis techniques using only one analytical means. These techniques include nuclear magnetic resonance (NMR), gas chromatography-mass spectrometry (GC-MS), and liquid chromatography-mass spectrometry (LC-MS), etc.; with these techniques, some favourable outcomes have been gained in the toxic reaction studies of TCM, such as the action target organs assay, the establishment of action pattern, the elucidation of action mechanism and the exploration of action material foundation. However, every analytical technique has its advantages and drawbacks, no existing analytical technique can be versatile. Multi-analysed techniques can partially overcome the shortcomings of single-analysed techniques. Combination of GC-MS and LC-MS metabolic profiling approaches has unravelled the pathological outcomes of aristolochic acid-induced nephrotoxicity, which can not be achieved by single-analysed techniques. It is believed that with the further development of metabonomic analytical techniques, especially multi-analysed techniques, metabonomics will greatly promote TCM toxicity research and be beneficial to the modernization of TCM in terms of extending the application of modern means in the TCM safety assessment, assisting the formulation of TCM safety norms and establishing the international standards indicators. PMID:19508399

  13. Blind percutaneous liver biopsy in infants and children: Comparison of safety and efficacy of percussion technique and ultrasound assisted technique.

    PubMed

    Mogahed, Engy A; Mansy, Yasmeen A; Al Hawi, Yasmeen; El-Sayed, Rokaya; El-Raziky, Mona; El-Karaksy, Hanaa

    2016-12-01

    Liver biopsy remains the most reliable method to diagnose various hepatic disorders in children. We aimed to assess the technical success and complication rate of ultrasound (US) assisted percutaneous liver biopsy versus transthoracic percussion guided technique in paediatrics. This randomized controlled study included all cases performing liver biopsy at Paediatric Hepatology Unit, Cairo University Paediatric Hospital over 12months. Patients were 102 cases; 62 were males, with age range 18days to 12years. Fifty seven procedures were done using the percussion guided technique and 45 cases were US assisted. The total number of complicated biopsies was 14 (13.7%), with more serious complications occurring in the percussion group. Complications were more frequent with younger age, lower platelet count, number of passes and occurrence of hypotension. US assisted percutaneous liver biopsy, although more costly, but may be safer to perform particularly in younger age. Copyright © 2016 Pan-Arab Association of Gastroenterology. Published by Elsevier B.V. All rights reserved.

  14. A novel technique for fetal heart rate estimation from Doppler ultrasound signal

    PubMed Central

    2011-01-01

    Background The currently used fetal monitoring instrumentation that is based on Doppler ultrasound technique provides the fetal heart rate (FHR) signal with limited accuracy. It is particularly noticeable as significant decrease of clinically important feature - the variability of FHR signal. The aim of our work was to develop a novel efficient technique for processing of the ultrasound signal, which could estimate the cardiac cycle duration with accuracy comparable to a direct electrocardiography. Methods We have proposed a new technique which provides the true beat-to-beat values of the FHR signal through multiple measurement of a given cardiac cycle in the ultrasound signal. The method consists in three steps: the dynamic adjustment of autocorrelation window, the adaptive autocorrelation peak detection and determination of beat-to-beat intervals. The estimated fetal heart rate values and calculated indices describing variability of FHR, were compared to the reference data obtained from the direct fetal electrocardiogram, as well as to another method for FHR estimation. Results The results revealed that our method increases the accuracy in comparison to currently used fetal monitoring instrumentation, and thus enables to calculate reliable parameters describing the variability of FHR. Relating these results to the other method for FHR estimation we showed that in our approach a much lower number of measured cardiac cycles was rejected as being invalid. Conclusions The proposed method for fetal heart rate determination on a beat-to-beat basis offers a high accuracy of the heart interval measurement enabling reliable quantitative assessment of the FHR variability, at the same time reducing the number of invalid cardiac cycle measurements. PMID:21999764

  15. Acoustic angiography: a new high frequency contrast ultrasound technique for biomedical imaging

    NASA Astrophysics Data System (ADS)

    Shelton, Sarah E.; Lindsey, Brooks D.; Gessner, Ryan; Lee, Yueh; Aylward, Stephen; Lee, Hyunggyun; Cherin, Emmanuel; Foster, F. Stuart; Dayton, Paul A.

    2016-05-01

    Acoustic Angiography is a new approach to high-resolution contrast enhanced ultrasound imaging enabled by ultra-broadband transducer designs. The high frequency imaging technique provides signal separation from tissue which does not produce significant harmonics in the same frequency range, as well as high resolution. This approach enables imaging of microvasculature in-vivo with high resolution and signal to noise, producing images that resemble x-ray angiography. Data shows that acoustic angiography can provide important information about the presence of disease based on vascular patterns, and may enable a new paradigm in medical imaging.

  16. Ultrasound-Guided Obturator Nerve Block: A Focused Review on Anatomy and Updated Techniques

    PubMed Central

    Nakamoto, Tatsuo; Kamibayashi, Takahiko

    2017-01-01

    This review outlines the anatomy of the obturator nerve and the indications for obturator nerve block (ONB). Ultrasound-guided ONB techniques and unresolved issues regarding these procedures are also discussed. An ONB is performed to prevent thigh adductor jerk during transurethral resection of bladder tumor, provide analgesia for knee surgery, treat hip pain, and improve persistent hip adductor spasticity. Various ultrasound-guided ONB techniques can be used and can be classified according to whether the approach is distal or proximal. In the distal approach, a transducer is placed at the inguinal crease; the anterior and posterior branches of the nerve are then blocked by two injections of local anesthetic directed toward the interfascial planes where each branch lies. The proximal approach comprises a single injection of local anesthetic into the interfascial plane between the pectineus and obturator externus muscles. Several proximal approaches involving different patient and transducer positions are reported. The proximal approach may be superior for reducing the dose of local anesthetic and providing successful blockade of the obturator nerve, including the hip articular branch, when compared with the distal approach. This hypothesis and any differences between the proximal ONB techniques need to be explored in future studies. PMID:28280738

  17. Speckle noise reduction in ultrasound images using a discrete wavelet transform-based image fusion technique.

    PubMed

    Choi, Hyun Ho; Lee, Ju Hwan; Kim, Sung Min; Park, Sung Yun

    2015-01-01

    Here, the speckle noise in ultrasonic images is removed using an image fusion-based denoising method. To optimize the denoising performance, each discrete wavelet transform (DWT) and filtering technique was analyzed and compared. In addition, the performances were compared in order to derive the optimal input conditions. To evaluate the speckle noise removal performance, an image fusion algorithm was applied to the ultrasound images, and comparatively analyzed with the original image without the algorithm. As a result, applying DWT and filtering techniques caused information loss and noise characteristics, and did not represent the most significant noise reduction performance. Conversely, an image fusion method applying SRAD-original conditions preserved the key information in the original image, and the speckle noise was removed. Based on such characteristics, the input conditions of SRAD-original had the best denoising performance with the ultrasound images. From this study, the best denoising technique proposed based on the results was confirmed to have a high potential for clinical application.

  18. Real-Time MRI Navigated Ultrasound for Preoperative Tumor Evaluation in Breast Cancer Patients: Technique and Clinical Implementation.

    PubMed

    Park, Ah Young; Seo, Bo Kyoung

    2016-01-01

    Real-time magnetic resonance imaging (MRI) navigated ultrasound is an image fusion technique to display the results of both MRI and ultrasonography on the same monitor. This system is a promising technique to improve lesion detection and analysis, to maximize advantages of each imaging modality, and to compensate the disadvantages of both MRI and ultrasound. In evaluating breast cancer stage preoperatively, MRI and ultrasound are the most representative imaging modalities. However, sometimes difficulties arise in interpreting and correlating the radiological features between these two different modalities. This pictorial essay demonstrates the technical principles of the real-time MRI navigated ultrasound, and clinical implementation of the system in preoperative evaluation of tumor extent, multiplicity, and nodal status in breast cancer patients.

  19. Doppler ultrasound surveillance in deep tunneling compressed-air work with Trimix breathing: bounce dive technique compared to saturation-excursion technique.

    PubMed

    Vellinga, T P van Rees; Sterk, W; de Boer, A G E M; van der Beek, A J; Verhoeven, A C; van Dijk, F J H

    2008-01-01

    The Western Scheldt Tunneling Project in The Netherlands provided a unique opportunity to evaluate two deep-diving techniques with Doppler ultrasound surveillance. Divers used the bounce diving techniques for repair and maintenance of the TBM. The tunnel boring machine jammed at its deepest depth. As a result the work time was not sufficient. The saturation diving technique was developed and permitted longer work time at great depth. Thirty-one divers were involved in this project. Twenty-three divers were examined using Doppler ultrasound. Data analysis addressed 52 exposures to Trimix at 4.6-4.8 bar gauge using the bounce technique and 354 exposures to Trimix at 4.0-6.9 bar gauge on saturation excursions. No decompression incidents occurred with either technique during the described phase of the project. Doppler ultrasound revealed that the bubble loads assessed in both techniques were generally low. We find out, that despite longer working hours, shorter decompression times and larger physical workloads, the saturation-excursion technique was associated with significant lower bubble grades than in the bounce technique using Doppler Ultrasound. We conclude that the saturation-excursion technique with Trimix is a good option for deep and long exposures in caisson work. The Doppler technique proved valuable, and it should be incorporated in future compressed-air work.

  20. Dynamics of nanometer- and submicrometer-sized particles in suspension probed by dynamic ultrasound scattering techniques

    NASA Astrophysics Data System (ADS)

    Kobayashi, Keisuke; Norisuye, Tomohisa; Sugita, Kazuki; Nakanishi, Hideyuki; Tran-Cong-Miyata, Qui

    2017-07-01

    The Dynamic ultraSound Scattering (DSS) technique, which is an acoustic analog of dynamic light scattering (DLS), has been developed to achieve particle sizing with a wide range of particle sizes from nanometers to micrometers. In the submicron regime, it was difficult to evaluate the particle size by DSS because of the competition between the Brownian and sedimentation motions as we addressed in the previous work [Igarashi et al., J. Appl. Phys. 115, 203506 (2014)]. We propose here a new function to evaluate the particle size in the submicron regime, and with 10% accuracy, the good agreement between DSS and Field-Emission Scanning Electron Microscopy results was confirmed. By improving the transducer, the recording system, as well as the analysis technique, the detectable particle size by the DSS technique now could be extended down to several tens of nanometers.

  1. Ultrasound Imaging and Its Modeling

    NASA Astrophysics Data System (ADS)

    Jensen, Jorgen A.

    Modern medical ultrasound scanners are used to image nearly all soft tissue structures in the body. The anatomy can be studied from gray-scale B-mode images, where the reflectivity and scattering strength of the tissues are displayed. The imaging is performed in real time with 20 to 100 images per second. The technique is widely used, since it does not use ionizing radiation and is safe and painless for the patient. This chapter gives a short introduction to modern ultrasound imaging using array transducers. It includes a description of the different imaging methods, the beam-forming strategies used, and the resulting fields and their modeling.

  2. Ex Vivo Assessment of an Ultrasound-Guided Injection Technique of the Navicular Bursa in the Horse.

    PubMed

    Perrin, R; Diguet, A C; Cantet, P; Bailly, C; Brogniez, L; Dugdale, A; Nisolle, J F; Vandeweerd, J M

    2016-12-01

    Synovitis of the navicular bursa is common in performance horses. The objective of this study was to describe an ultrasound-guided technique to inject a distended navicular bursa and to evaluate its feasibility for use by a clinician not trained in the technique. Twenty distal limbs of horses of various breeds and sizes were used. To produce synovial distension, the navicular bursa of each limb was injected with contrast medium using a lateral approach and radiography was performed to confirm that the contrast medium was distending the bursa. The digit was positioned with the distal interphalangeal joint in hyperextension. A microconvex ultrasound probe was placed in the hollow of the pastern, palmar to the middle phalanx and the region was assessed in a transverse plane slightly oblique to the horizontal plane. The ultrasound probe was rotated to visualize both the lateral and medial recesses and to select which side was more distended to inject. A 21G 0.8 × 50 mm needle was inserted abaxially to the probe in the plane of the ultrasound beam into the proximal recess of this navicular bursa and a methylene blue solution was injected. Following injection, dissection was performed to assess whether the navicular bursa had been successfully injected. This ultrasound-guided technique was reliably performed with a success rate of 68%. The success of injection is influenced by hyperextension of the foot, quality of ultrasound images and degree of distension of the bursa. © 2015 Blackwell Verlag GmbH.

  3. Therapeutic Modulation of Calcium Dynamics using Ultrasound and Other Energy-based Techniques.

    PubMed

    Castellanos, Ivan; Balteanu, Bogdan; Singh, Tania; Zderic, Vesna

    2016-04-21

    Ultrasound, along with other types of energy-based methods, has been widely investigated for use in various therapeutic applications because of its ability to stimulate specific biological processes. Many of these processes are mediated by calcium (Ca2+) signaling, thus making modulation of Ca2+ dynamics an evident therapeutic target for energy-based techniques. Various diseases have been associated with abnormal Ca2+ signaling and could therefore benefit from therapeutic approaches trying to regulate the transport of Ca2+ across cell membranes. Here, we review published literature on the use of mechanical, electrical, magnetic and electromagnetic energy in modulating Ca2+ transients with particular emphasis on therapeutic ultrasound. We further provide brief discussions on the role of Ca2+ in living cells and the use of different experimental techniques to determine and measure its contribution to different biological processes. Finally, we explore the benefits, limitations and potential clinical applications of different energy-based modalities that can be utilized in modulation of Ca2+ signaling.

  4. Ultrasound Elastography--Review of Techniques and Its Clinical Applications in Pediatrics--Part 1.

    PubMed

    Pawluś, Aleksander; Sokołowska-Dąbek, Dąbrówka; Szymańska, Kinga; Inglot, Marcin S; Zaleska-Dorobisz, Urszula

    2015-01-01

    Sonoelastography is a novel technique that uses ultrasound waves to assess the elasticity of tissues noninvasively. It provides an ultrasound-based method to detect and display the relative stiffness of tissue. The main principle of sonoelastography is the measurement of tissue distortion in response to external compression. Changes in elasticity and tissue deformation elicited by compression are measured, processed and then shown in real time presentation with color-coded elastograms. One of the most important applications of sonoelastography is the evaluation of liver diseases, mainly liver fibrosis assessment and staging. Although in terms of definite diagnosis the liver biopsy still remains the golden standard, elastography seems to be a very inexpensive, repeatable and noninvasive method to evaluate most of liver conditions. The technique is also applicable in detection and differential diagnosis of focal lesions. It provides better imaging information and therefore more accurate evaluation of the lesions nature, e.g. in liver, lymphatic nodes or thyroid gland. Most of the applications mentioned above are well known and have been described in details in adults. Similarly, most of sonoelastographic studies are based on groups of adults. The purpose of this review article is to bring this technology closer to pediatric clinicians and to summarize some of its current clinical applications that are being pursued. In this part we focus on utility of elastography in liver assessment in pediatric patients.

  5. Conventional Landmark-Guided Midline Versus Preprocedure Ultrasound-Guided Paramedian Techniques in Spinal Anesthesia.

    PubMed

    Kallidaikurichi Srinivasan, Karthikeyan; Iohom, Gabriella; Loughnane, Frank; Lee, Peter J

    2015-10-01

    Multiple passes and attempts while administering spinal anesthesia are associated with a greater incidence of postdural puncture headache, paraesthesia, and spinal hematoma. We hypothesized that the routine use of a preprocedural ultrasound-guided paramedian technique for spinal anesthesia would reduce the number of passes required to achieve entry into the subarachnoid space when compared with the conventional landmark-guided midline approach. One hundred consenting patients scheduled for elective total joint replacements (hip and knee) were randomized into group C (conventional) and group P (preprocedural ultrasound-guided paramedian technique) with 50 in each group. The patients were blinded to the study group. All spinal anesthetics were administered by a consultant anesthesiologist. In group C, spinal anesthetic was done via the midline approach using clinically palpated landmarks. In group P, a preprocedural ultrasound scan was used to mark the paramedian insertion site, and spinal anesthetic was performed via the paramedian approach. The average number of passes (defined as the number of forward advancements of the spinal needle in a given interspinous space, i.e., withdrawal and redirection of spinal needle without exiting the skin) in group P was approximately 0.34 times that in group C, a difference that was statistically significant (P = 0.01). Similarly, the average number of attempts (defined as the number of times the spinal needle was withdrawn from the skin and reinserted) in group P was approximately 0.25 times that of group C (P = 0.0021). In group P, on an average, it took 81.5 (99% confidence interval, 68.4-97 seconds) seconds longer to identify the landmarks than in group C (P = 0.0002). All other parameters, including grading of palpated landmarks, time taken for spinal anesthetic injection, periprocedural pain scores, periprocedural patient discomfort visual analog scale score, conversion to general anesthetic, paresthesia, and radicular pain

  6. Characterization of Zirconium Hydride Orientations in Zircaloy Cladding Tubes with a Laser Ultrasound Technique

    NASA Astrophysics Data System (ADS)

    Yeh, Cheng-Hung; Yang, Che-Hua

    2010-02-01

    This research is focused on characterizing Zircaloy cladding tubes with different concentration ratios between radially(R) orientated hydrides and circumferential(C) ones. A procedure corporate with an experimental technique and an inversion algorism is used to investigate the effects of R/C ratio on the dispersion spectra of GW. A laser ultrasound technique (LUT) is used to measure the dispersions of circumferentially guided waves (CGW) propagating along the circumferential direction of the cladding tubes. An inversion algorism based on simplex method is used to extract interested properties from the measured GW dispersion spectra. It is shown that the procedure introduced in the current research is able to relate the phase velocities with hydrogen concentration. In the meanwhile, this procedure is able to distinguish the R/C ratio in a quantitative way as well. It is also found out that the bulk elastic modulus increases as the R/C ratio increases.

  7. Ultrasound contrast imaging: influence of scatterer motion in multi-pulse techniques.

    PubMed

    Lin, Fanglue; Cachard, Christian; Mori, Riccardo; Varray, Francois; Guidi, Francesco; Basset, Olivier

    2013-10-01

    In ultrasound contrast imaging, many techniques based on multiple transmissions have been proposed to increase the contrast-to-tissue ratio (CTR). They are generally based on the response of static scatterers inside the imaged region. However, scatterer motion, for example in blood vessels, has an inevitable influence on multi-pulse techniques, which can either enhance or degrade the technique involved. This paper investigates the response of static nonlinear media insonated by multi-pulses with various phase shifts, and the influence of scatterer motion on multi-pulse techniques. Simulations and experimental results from a single bubble and clouds of bubbles show that the phase shift of the echoes backscattered from bubbles is dependent on the transmissions' phase shift, and that the bubble motion influences the efficiency of multi-pulse techniques: fundamental and second-harmonic amplitudes of the processed signal change periodically, exhibiting maximum or minimum values, according to scatterer motion. Furthermore, experimental results based on the second-harmonic inversion (SHI) technique reveal that bubble motion can be taken into account to regulate the pulse repetition frequency (PRF). With the optimal PRF, the CTR of SHI images can be improved by about 12 dB compared with second-harmonic images.

  8. Prostate clinical study of a full inversion unconstrained ultrasound elastography technique

    NASA Astrophysics Data System (ADS)

    Mousavi, S. Reza; Sadeghi-Naini, Ali; Czarnota, Gregory J.; Samani, Abbas

    2014-03-01

    Prostate cancer detection at early stages is crucial for desirable treatment outcome. Among available imaging modalities, ultrasound (US) elastography is being developed as an effective clinical tool for prostate cancer diagnosis. Current clinical US elastography systems utilise strain imaging where tissue strain images are generated to approximate the tissue elastic modulus distribution. While strain images can be generated in real-time fashion, they lack the accuracy necessary for having desirable sensitivity and specificity. To improve strain imaging, full inversion based elastography techniques were proposed. Among these techniques, a constrained elastography technique was developed which showed promising results as long as the tumor and prostate geometry can be obtained accurately from the imaging modality used in conjunction with the elastography system. This requirement is not easy to fulfill, especially with US imaging. To address this issue, we present an unconstrained full inversion prostate elastography method in conjunction with US imaging where knowledge of tissue geometry is not necessary. One of the reasons that full inversion elastography techniques have not been routinely used in the clinic is lack of clinical validation studies. To our knowledge, no quasistatic full inversion based prostate US elastography technique has been applied in vivo before. In this work, the proposed method was applied to clinical prostate data and reconstructed elasticity images were compared to corresponding annotated histopathology images which is the first quasi-static full inversion based prostate US elastography technique applied successfully in vivo. Results demonstrated a good potential for clinical utility of the proposed method.

  9. A review of modern instrumental techniques for measurements of ice cream characteristics.

    PubMed

    Bahram-Parvar, Maryam

    2015-12-01

    There is an increasing demand of the food industries and research institutes to have means of measurement allowing the characterization of foods. Ice cream, as a complex food system, consists of a frozen matrix containing air bubbles, fat globules, ice crystals, and an unfrozen serum phase. Some deficiencies in conventional methods for testing this product encourage the use of alternative techniques such as rheometry, spectroscopy, X-ray, electro-analytical techniques, ultrasound, and laser. Despite the development of novel instrumental applications in food science, use of some of them in ice cream testing is few, but has shown promising results. Developing the novel methods should increase our understanding of characteristics of ice cream and may allow online testing of the product. This review article discusses the potential of destructive and non-destructive methodologies in determining the quality and characteristics of ice cream and similar products.

  10. Screening and early diagnosis of osteoporosis through X-ray and ultrasound based techniques

    PubMed Central

    Pisani, Paola; Renna, Maria Daniela; Conversano, Francesco; Casciaro, Ernesto; Muratore, Maurizio; Quarta, Eugenio; Paola, Marco Di; Casciaro, Sergio

    2013-01-01

    Effective prevention and management of osteoporosis would require suitable methods for population screenings and early diagnosis. Current clinically-available diagnostic methods are mainly based on the use of either X-rays or ultrasound (US). All X-ray based methods provide a measure of bone mineral density (BMD), but it has been demonstrated that other structural aspects of the bone are important in determining fracture risk, such as mechanical features and elastic properties, which cannot be assessed using densitometric techniques. Among the most commonly used techniques, dual X-ray absorptiometry (DXA) is considered the current “gold standard” for osteoporosis diagnosis and fracture risk prediction. Unfortunately, as other X-ray based techniques, DXA has specific limitations (e.g., use of ionizing radiation, large size of the equipment, high costs, limited availability) that hinder its application for population screenings and primary care diagnosis. This has resulted in an increasing interest in developing reliable pre-screening tools for osteoporosis such as quantitative ultrasound (QUS) scanners, which do not involve ionizing radiation exposure and represent a cheaper solution exploiting portable and widely available devices. Furthermore, the usefulness of QUS techniques in fracture risk prediction has been proven and, with the last developments, they are also becoming a more and more reliable approach for assessing bone quality. However, the US assessment of osteoporosis is currently used only as a pre-screening tool, requiring a subsequent diagnosis confirmation by means of a DXA evaluation. Here we illustrate the state of art in the early diagnosis of this “silent disease” and show up recent advances for its prevention and improved management through early diagnosis. PMID:24349644

  11. Solving real decay and conservation problems of building materials by ultrasounds technique

    NASA Astrophysics Data System (ADS)

    Alvarez de Buergo, Monica; Fort, Rafael; Gomez-Heras, Miguel; Vazquez-Calvo, Carmen

    2010-05-01

    In this study a variety of case studies and different building materials in which ultrasounds velocity played a significant role are shown, either to characterize building materials, to measure deterioration, to assess conservation techniques or for preventive purposes. Regarding to materials properties, ultrasounds velocity provided interesting indices such as the quality index (useful when selecting replacing materials, materials for new constructions or either for sculptures); alteration index (very much related to pores and voids, and fissures); mechanical strength (assessing its reduction when materials are affected by several decay processes, being fire one of them) or anisotropy indices, which highly condition the decay of elements and materials in buildings and sculptures, and which vary themselves with decay progress. The technique is also a tool for detecting and locating elements inside structures, like metallic ones, and also to detect and locate discontinuities inside elements, both for consolidation purposes or even in cases of structures movement, which is quite common nowadays. Using some specific software, ultrasounds results can be plotted as iso-areas, which allows to define areas or zones of structures with the highest risk of detachment in a short-time in order to plan the most adequate interventions. Not new is also the aid of ultrasonics to assess consolidation products and to determine the degree of materials decay when submitted to artificial ageing. Much more innovative is the fact that ultrasonics measurement can be also helpful to determine different building periods in a same building, even the fact of determining an element's lifetime. The results obtained by this non destructive and portable technique that will be presented in this session correspond to both real case studies (results that helped to solve a real problem), some of them corresponding to emblematic monuments de España (Royal Palace of Madrid and some other monuments

  12. Ultrasound physics and instrumentation for pathologists.

    PubMed

    Lieu, David

    2010-10-01

    Interest in pathologist-performed ultrasound-guided fine-needle aspiration is increasing. Educational courses discuss clinical ultrasound and biopsy techniques but not ultrasound physics and instrumentation. To review modern ultrasound physics and instrumentation to help pathologists understand the basis of modern ultrasound. A review of recent literature and textbooks was performed. Ultrasound physics and instrumentation are the foundations of clinical ultrasound. The key physical principle is the piezoelectric effect. When stimulated by an electric current, certain crystals vibrate and produce ultrasound. A hand-held transducer converts electricity into ultrasound, transmits it into tissue, and listens for reflected ultrasound to return. The returning echoes are converted into electrical signals and used to create a 2-dimensional gray-scale image. Scanning at a high frequency improves axial resolution but has low tissue penetration. Electronic focusing moves the long-axis focus to depth of the object of interest and improves lateral resolution. The short-axis focus in 1-dimensional transducers is fixed, which results in poor elevational resolution away from the focal zone. Using multiple foci improves lateral resolution but degrades temporal resolution. The sonographer can adjust the dynamic range to change contrast and bring out subtle masses. Contrast resolution is limited by processing speed, monitor resolution, and gray-scale perception of the human eye. Ultrasound is an evolving field. New technologies include miniaturization, spatial compound imaging, tissue harmonics, and multidimensional transducers. Clinical cytopathologists who understand ultrasound physics, instrumentation, and clinical ultrasound are ready for the challenges of cytopathologist-performed ultrasound-guided fine-needle aspiration and core-needle biopsy in the 21st century.

  13. Sex-determination and sex-preselection tests in India: modern techniques for femicide.

    PubMed

    Patel, V

    1989-01-01

    "In India during recent years techniques that were developed to detect genetic deformities in fetuses have been increasingly used mainly for determining the sex of fetuses so that female fetuses can be exterminated. This paper explores the factors underlying this practice and the related practice of preselecting the sex of offspring, examining both the widespread availability and use of sex-determination and sex-preselection techniques and the root causes of female devaluation in India. Also presented and analyzed are the responses of women's groups and the government to these uses of modern technology to carry out the ultimate abuse of women--not allowing them to be born."

  14. Compensation technique for the intrinsic error in ultrasound motion estimation using a speckle tracking method

    NASA Astrophysics Data System (ADS)

    Taki, Hirofumi; Yamakawa, Makoto; Shiina, Tsuyoshi; Sato, Toru

    2015-07-01

    High-accuracy ultrasound motion estimation has become an essential technique in blood flow imaging, elastography, and motion imaging of the heart wall. Speckle tracking has been one of the best motion estimators; however, conventional speckle-tracking methods neglect the effect of out-of-plane motion and deformation. Our proposed method assumes that the cross-correlation between a reference signal and a comparison signal depends on the spatio-temporal distance between the two signals. The proposed method uses the decrease in the cross-correlation value in a reference frame to compensate for the intrinsic error caused by out-of-plane motion and deformation without a priori information. The root-mean-square error of the estimated lateral tissue motion velocity calculated by the proposed method ranged from 6.4 to 34% of that using a conventional speckle-tracking method. This study demonstrates the high potential of the proposed method for improving the estimation of tissue motion using an ultrasound speckle-tracking method in medical diagnosis.

  15. Ultrasound Elastography--Review of Techniques and Its Clinical Applications in Pediatrics--Part 2.

    PubMed

    Zaleska-Dorobisz, Urszula; Pawluś, Aleksander; Szymańska, Kinga; Łasecki, Mateusz; Ziajkiewicz, Marcin

    2015-01-01

    Sonoelastography is a novel technique that uses ultrasound waves to assess the elasticity of tissues noninvasively. It provides an ultrasound-based method to detect and display the relative stiffness of tissue. The main principle of sonoelastography is the measurement of tissue distortion in response to external compression. Changes in elasticity and tissues deformation elicited by compression are measured, processed and then shown in real time presentation with color-coded elastograms. Most of the elastography applications are well known and have been described in detail in adults, e.g. evaluation of liver fibrosis or thyroid nodules. Similarly, most of sonoelastographic studies are based on groups of adults. The purpose of this review article is to bring this technology closer to pediatric clinicians and to summarize some of its current clinical applications that are being pursued. In this part we take into consideration utility of elastography in evaluation pathologies of musculoskeletal system, lymphatic nodes, thyroid, kidneys in pediatric patients and also elastography of placenta.

  16. Ultrasound-guided catheterisation of the subclavian vein: freehand vs needle-guided technique.

    PubMed

    Maecken, T; Heite, L; Wolf, B; Zahn, P K; Litz, R J

    2015-11-01

    The objective of this prospective, randomised study was to examine the impact of a multi-angle needle guide for ultrasound-guided, in-plane, central venous catheter placement in the subclavian vein. One hundred and sixty patients were randomly allocated to two groups, freehand or needle-guided, and then 159 catheterisations were analysed. Cannulation of the first examined access site was successful in 96.9% of cases with no significant difference between groups. There were three arterial punctures and no other severe injuries. Catheter misplacements did not differ between the groups. Higher success rates within the first and second attempts in the needle-guided group were observed (p = 0.041 and p = 0.019, respectively). Use of the needle guide reduced the access time from a median (IQR [range]) of 30 (18-76 [6-1409]) s to 16 (10-30 [4-295]) s; p = 0.0001, and increased needle visibility from 31.8% (9.7%-52.2% [0-96.67]) to 86.2% (62.5%-100% [0-100]); p < 0.0001. A multi-angle needle guide significantly improved aligning the needle and ultrasound plane compared with the freehand technique when cannulating the subclavian vein. Use of the guide resulted in faster access times and increased success at the first and second attempts.

  17. Endoscopic ultrasound-guided hepatic and perihepatic abscess drainage: an evolving technique

    PubMed Central

    Changela, Kinesh; Lane, Devin; Anand, Sury; Duddempudi, Sushil

    2014-01-01

    Interventional radiology-guided percutaneous drainage of liver abscesses with concomitant use of antibiotics has been the conventional approach for the treatment of liver abscesses. Hepatic abscesses refractory or not amenable to percutaneous drainage have been treated with surgical drainage, either via laparoscopic or open laparotomy techniques. The aim of this review was to evaluate the technical feasibility and efficacy of endoscopic ultrasound (EUS)-guided drainage of liver abscesses. A literature review was performed to identify the studies describing the technique. In this review article we have summarized case series or reports describing EUS-guided liver abscess drainage. The indications, techniques, endoprostheses, limitations and complications reported are discussed. A total of seven cases have been described so far in the literature which included patients with failed conventional treatment modalities. The EUS-guided drainage technique involves puncturing the abscess using endosonography to gain access, passing a guidewire followed by tract dilation and placement of an endoprosthesis for drainage. Studies have reported 100% technical and clinical success rates in selected cases. No complications were reported. EUS-guided drainage of liver abscesses can be a safe and effective alternative approach in the management of liver abscesses in selected patients. PMID:24587822

  18. [Ultrasound diagnostics of diffuse liver diseases].

    PubMed

    Jung, E M; Wiggermann, P; Stroszczynski, C; Reiser, M F; Clevert, D-A

    2012-08-01

    The current improvements in modern high resolution ultrasound technology, like Tissue Harmonic Imaging (THI), Speckle Reduction Imaging (SRI), partial color coding of B-mode (Color Coded Imaging), and also the advent of ultrasound based elastography as well as contrast-enhanced ultrasound (CEUS) offer fundamentally new ways to characterize diffuse alterations of the liver parenchyma. Besides metabolic disease, disorders of liver fat distribution, infectious and malignant diseases can cause diffuse alterations of the liver parenchyma. In case of liver fibrosis, only a combination of different ultrasound techniques including CEUS, allows the differentiation between benign dysplastic and malignant lesions. Ultrasound elastography allows assessing the extent of the fibrosis. This article focuses on the different ultrasound based diagnostic possibilities in case of diffuse liver disease.

  19. Modern morphological engineering techniques for improving productivity of filamentous fungi in submerged cultures.

    PubMed

    Antecka, Anna; Bizukojc, Marcin; Ledakowicz, Stanislaw

    2016-12-01

    Morphological engineering techniques have recently gained popularity as they are used for increasing the productivity of a variety of metabolites and enzymes in fungi growing in submerged cultures. Their action is mainly associated with the changes they evoke in fungal morphology. Traditional morphological engineering approaches include manipulation of spore concentration, pH-shifting and mechanical stress exerted by stirring and aeration. As the traditional methods proved to be insufficient, modern techniques such as changes of medium osmolality or addition of mineral microparticles to the media (microparticle-enhanced cultivation, MPEC) were proposed. Despite the fact that this area of knowledge is still being developed, there are a fair amount of scientific articles concerning the cultivations of filamentous fungi with the use of these techniques. It was described that in Ascomycetes fungi both MPEC or change of osmolality successfully led to the change of mycelial morphology, which appeared to be favorable for increased productivity of secondary metabolites and enzymes. There are also limited but very promising reports involving the successful application of MPEC with Basidiomycetes species. Despite the fact that the mineral microparticles behave differently for various microorganisms, being strain and particle specific, the low cost of its application is a great benefit. This paper reviews the application of the modern morphology engineering techniques. The authors critically assess the advantages, shortcomings, and future prospects of their application in the cultivation of fungi.

  20. [Consensus document on ultrasound training in Intensive Care Medicine. Care process, use of the technique and acquisition of professional skills].

    PubMed

    Ayuela Azcárate, J M; Clau-Terré, F; Vicho Pereira, R; Guerrero de Mier, M; Carrillo López, A; Ochagavia, A; López Pérez, J M; Trenado Alvarez, J; Pérez, L; Llompart-Pou, J A; González de Molina, F J; Fojón, S; Rodríguez Salgado, A; Martínez Díaz, M C; Royo Villa, C; Romero Bermejo, F J; Ruíz Bailén, M; Arroyo Díez, M; Argueso García, M; Fernández Fernández, J L

    2014-01-01

    Ultrasound has become an essential tool in assisting critically ill patients. His knowledge, use and instruction requires a statement by scientific societies involved in its development and implementation. Our aim are to determine the use of the technique in intensive care medicine, clinical situations where its application is recommended, levels of knowledge, associated responsibility and learning process also implement the ultrasound technique as a common tool in all intensive care units, similar to the rest of european countries. The SEMICYUC's Working Group Cardiac Intensive Care and CPR establishes after literature review and scientific evidence, a consensus document which sets out the requirements for accreditation in ultrasound applied to the critically ill patient and how to acquire the necessary skills. Training and learning requires a structured process within the specialty. The SEMICYUC must agree to disclose this document, build relationships with other scientific societies and give legal cover through accreditation of the training units, training courses and different levels of training.

  1. Learning mediastinoscopy: the need for education, experience and modern techniques--interdependency of the applied technique and surgeon's training level.

    PubMed

    Walles, Thorsten; Friedel, Godehard; Stegherr, Tobias; Steger, Volker

    2013-04-01

    Mediastinoscopy represents the gold standard for invasive mediastinal staging. While learning and teaching the surgical technique are challenging due to the limited accessibility of the operation field, both benefited from the implementation of video-assisted techniques. However, it has not been established yet whether video-assisted mediastinoscopy improves the mediastinal staging in itself. Retrospective single-centre cohort analysis of 657 mediastinoscopies performed at a specialized tertiary care thoracic surgery unit from 1994 to 2006. The number of specimens obtained per procedure and per lymph node station (2, 4, 7, 8 for mediastinoscopy and 2-9 for open lymphadenectomy), the number of lymph node stations examined, sensitivity and negative predictive value with a focus on the technique employed (video-assisted vs standard technique) and the surgeon's experience were calculated. Overall sensitivity was 60%, accuracy was 90% and negative predictive value 88%. With the conventional technique, experience alone improved sensitivity from 49 to 57% and it was predominant at the paratracheal right region (from 62 to 82%). But with the video-assisted technique, experienced surgeons rose sensitivity from 57 to 79% in contrast to inexperienced surgeons who lowered sensitivity from 49 to 33%. We found significant differences concerning (i) the total number of specimens taken, (ii) the amount of lymph node stations examined, (iii) the number of specimens taken per lymph node station and (iv) true positive mediastinoscopies. The video-assisted technique can significantly improve the results of mediastinoscopy. A thorough education on the modern video-assisted technique is mandatory for thoracic surgeons until they can fully exhaust its potential.

  2. Transvaginal ultrasound

    MedlinePlus

    ... Uterine bleeding - transvaginal ultrasound; Menstrual bleeding - transvaginal ultrasound; Infertility - transvaginal ultrasound; Ovarian - transvaginal ultrasound; Abscess - transvaginal ultrasound

  3. Ultrasound pregnancy

    MedlinePlus

    Pregnancy sonogram; Obstetric ultrasonography; Obstetric sonogram; Ultrasound - pregnancy; IUGR - ultrasound; Intrauterine growth - ultrasound; Polyhydramnios - ultrasound; Oligohydramnios - ultrasound; ...

  4. A novel three-dimensional endoscopic ultrasound technique for the freehand examination of the oesophagus.

    PubMed

    Inglis, Scott; Christie, Derek; Plevris, John N

    2011-11-01

    This study details the development and evaluation of a freehand radial three-dimensional endoscopic ultrasound (3D-EUS) technique for use in the upper gastro-intestinal tract. It comprised of a commercial EUS system, a custom acquisition system to simultaneous acquire radial B-mode images and corresponding incremental changes in position of the scope as it was withdrawn and a custom 3D-EUS package written in Matlab™, to reconstruct and analyse the volume. This technique was evaluated using an EUS phantom with embedded objects of known dimensions and volumes and with clinical images acquired during routine cancer staging. For the phantom measurements, average Z-dimensional error was <1% and volume errors were 1.4% (volume(1) = 48930 mm(3)) and 4.5% (volume(2) = 5100 mm(3)). Application of this technique to EUS acquired clinical images produced excellent characterisation of oesophageal structures and accurate dimension and volume measurements. It also enabled the endoscopist to review "off-line" the EUS examination in case important information was missed.

  5. Coronary bifurcation lesions treated with double kissing crush technique compared to classical crush technique: serial intravascular ultrasound analysis.

    PubMed

    Shan, Shou-Jie; Ye, Fei; Liu, Zhi-Zhong; Tian, Nai-Liang; Zhang, Jun-Jie; Chen, Shao-Liang

    2013-04-01

    The double kissing (DK) crush technique is a modified version of the crush technique. It is specifically designed to increase the success rate of the final kissing balloon post-dilatation, but its efficacy and safety remain unclear. Data were obtained from the DKCRUSH-I trial, a prospective, randomized, multi-center study to evaluate safety and efficacy. Post-procedural and eight-month follow-up intravascular ultrasound (IVUS) analysis was available in 61 cases. Volumetric analysis using Simpson's method within the Taxus stent, and cross-sectional analysis at the five sites of the main vessel (MV) and three sites of the side branch (SB) were performed. Impact of the bifurcation angle on stent expansion at the carina was also evaluated. Stent expansion in the SB ostium was significantly less in the classical crush group ((53.81 ± 13.51)%) than in the DK crush group ((72.27 ± 11.46)%) (P = 0.04). For the MV, the incidence of incomplete crush was 41.9% in the DK group and 70.0% in the classical group (P = 0.03). The percentage of neointimal area at the ostium had a tendency to be smaller in the DK group compared with the classical group ((16.4 ± 19.2)% vs. (22.8 ± 27.1)%, P = 0.06). The optimal threshold of post-procedural minimum stent area (MSA) to predict follow-up minimum lumen area (MLA) < 4.0 mm(2) at the SB ostium was 4.55 mm(2), yielding an area under the curve of 0.80 (95% confidence interval: 0.61 to 0.92). Our data suggest that the DK crush technique is associated with improved quality of the final kissing balloon inflation (FKBI) and had smaller optimal cutoff value of post-procedural MSA at the SB ostium.

  6. MODERN PROPAGATION TECHNIQUES- A CONSERVAION TOOL FOR CERTAIN ENDEMIC MEDICINAL PLANTS IN NILGIRI BIOSPHERE RESERVE

    PubMed Central

    Paulsamy, S.; Arumugasamy, K.

    2002-01-01

    There plant species of medicinal and vegatational fire break importance such as Berberis tinctoria, Elaegnus kologa and Rhodomyrtus tomentosa were identified in Nilgiri Biosphere Reserve and their eco-physiological behaviors were analysed. The study revealed that generally all the there species were having shorter period of seed dormacy, poor viability of seeds and higher mortality of saplings. These poor eco-physiological features are the major factors for their limited distribution, lesser population and weaker establishment. Hence to overcome these factors the modern reproductive strategies like tissue culture techniques are suggested. PMID:22557048

  7. Modern propagation techniques- a conservaion tool for certain endemic medicinal plants in nilgiri biosphere reserve.

    PubMed

    Paulsamy, S; Arumugasamy, K

    2002-01-01

    There plant species of medicinal and vegatational fire break importance such as Berberis tinctoria, Elaegnus kologa and Rhodomyrtus tomentosa were identified in Nilgiri Biosphere Reserve and their eco-physiological behaviors were analysed. The study revealed that generally all the there species were having shorter period of seed dormacy, poor viability of seeds and higher mortality of saplings. These poor eco-physiological features are the major factors for their limited distribution, lesser population and weaker establishment. Hence to overcome these factors the modern reproductive strategies like tissue culture techniques are suggested.

  8. Ultrasound-guided percutaneous tenotomy for the treatment of iliopsoas impingement: a description of technique and case study.

    PubMed

    Sampson, Matthew J; Rezaian, Nimah; Hopkins, James M K

    2015-04-01

    Iliopsoas impingement is a commonly recognised source of groin pain following total hip replacement. When conservative measures fail, open or arthroscopic iliopsoas tendon release can reliably alleviate pain and improve function. This article describes an alternative ultrasound-guided percutaneous technique, achieving iliopsoas tenotomy utilising a modified 18G coaxial needle and thus minimising the morbidity and cost associated with an open or arthroscopic procedure. This method proved successful with resultant complete resolution of patient symptoms. To the knowledge of the authors, this is the first case of ultrasound-guided percutaneous iliopsoas tenotomy for iliopsoas impingement post total hip replacement. © 2015 The Royal Australian and New Zealand College of Radiologists.

  9. Strain-compounding technique with ultrasound Nakagami imaging for distinguishing between benign and malignant breast tumors.

    PubMed

    Liao, Yin-Yin; Li, Chia-Hui; Tsui, Po-Hsiang; Chang, Chien-Cheng; Kuo, Wen-Hung; Chang, King-Jen; Yeh, Chih-Kuang

    2012-05-01

    The scatterer properties of breast tissues are related to the presence of collagen structures, while the elasticity properties of breast tissues depend on their structural organization; these two characteristics are functionally complementary in ultrasound-based tissue characterizations. This study investigated the use of a strain-compounding technique with Nakagami imaging to provide information associated with the scatterer and elasticity characteristics of tissues when attempting to identify benign and malignant breast tumors. The efficacy of the proposed method was tested by collecting raw data of ultrasound backscattered signals from 50 clinical cases (25 benign tumors and 25 malignant tumors, as verified by histology biopsies). The different strain conditions were created by applying manual compression. For each region in which breast tumors were suspected, estimates of the full width at half maximum (FWHM) from the Gaussian fitting curve for the Nakagami-parameter histogram in the strain-compounding Nakagami images were divided by those of the corresponding reference Nakagami images (uncompressed images); this parameter was denoted as the FWHM ratio. Receiver operating characteristic (ROC) curve analysis was adopted to assess the diagnostic performance. The results demonstrated that the difference in scatterer distributions between before and after compounding was greater for benign tumors than for malignant tumors. The FWHM ratio estimates for benign and malignant tumors were 0.76 ± 0.14 and 0.96 ± 0.06 (mean ± standard deviation), respectively (p < 0.01). The mean area under the ROC curve using the FWHM ratio estimates was 0.92, with a 95% confidence interval of 0.83-1.00. These findings indicate that the strain-compounding Nakagami imaging method based on the acquisition of multiple frames under different strain states could provide objective information that would improve the ability to classify benign and malignant breast tumors.

  10. Delineation of atherosclerotic plaque using subharmonic imaging filtering techniques and a commercial intravascular ultrasound system.

    PubMed

    Sridharan, Anush; Eisenbrey, John R; Machado, Priscilla; deMuinck, Ebo D; Doyley, Marvin M; Forsberg, Flemming

    2013-01-01

    The ability to delineate atherosclerotic plaque from the surrounding tissue using custom-developed subharmonic imaging (SHI) digital filtering techniques was investigated in vivo using a commercially available system. Atherosclerosis was induced in the aorta of two Watanabe Heritable Hyperlipidemic rabbits following which injections of an ultrasound contrast agent (UCA) Definity (Lantheus Medical Imaging, N Billerica, Massachusetts) were administered. Imaging was performed using a Galaxy intravascular ultrasound (IVUS) scanner (Boston Scientific, Natick, Massachusetts) equipped with an Atlantis® SR Pro Imaging Catheter (Boston Scientific). Four preliminary band-pass filters were designed to isolate the subharmonic signal (from surrounding tissue) and applied to the radio-frequency (RF) data. Preliminary filter performances were compared in terms of vessel-tissue contrast-to-tissue ratio (CTR) and visual examination. Based on preliminary results, a subharmonic adaptive filter and a stopband (SB) filter were designed and applied to the RF data. Images were classified as fundamental, SHI, and SB. Four readers performed qualitative analysis of 168 randomly selected images (across all three imaging modes). The images were scored for overall image quality, image noise, plaque visualization, and vessel lumen visualization. A Wilcoxon signed-rank test was used to compare the scores followed by intraclass correlation (ICC) evaluation. Quantitative analysis was performed by calculating the CTRs for the vessel-to-plaque and vessel-to-tissue (compared using a paired student's t test). Qualitative analysis showed SHI and SB to have significantly less image noise relative to the fundamental mode (p < 0.001). Fundamental mode scored significantly higher than SHI and SB for the remaining three categories. ICC showed mixed results among reader evaluation for delineation of plaque. However, quantitatively, SHI produced the best vessel-plaque CTR.

  11. Can Abdominal Hypopressive Technique Change Levator Hiatus Area?: A 3-Dimensional Ultrasound Study.

    PubMed

    Resende, Ana Paula Magalhães; Torelli, Luiza; Zanetti, Miriam Raquel Diniz; Petricelli, Carla Dellabarba; Jármy-Di Bella, Zsuzsanna IIona Katalin; Nakamura, Mary Uchiyama; Araujo Júnior, E; Moron, Antonio Fernandes; Girão, Manoel João Batista Castello; Sartori, Marair Gracio Ferreira

    2016-06-01

    This study aimed to evaluate the levator hiatus area (LHA) at rest and during the performance of maximal pelvic floor muscle (PFM) contractions, during the abdominal hypopressive technique (AHT), and during the combination of PFM contractions (PFMCs) and the AHT. The study included 17 healthy nulliparous women who had no history of pelvic floor disorders. The LHA was evaluated with the patients in the lithotomy position. After a physiotherapist instructed the patients on the proper performance of the PFM and AHT exercises, 1 gynecologist performed the 3-dimensional translabial ultrasound examinations. The LHA was measured with the patients at rest. The PFMC alone, the AHT alone or the AHT in combination with a PFMC with 30 seconds of rest between the evaluations were performed. Each measurement was performed 2 times, and the mean value was used for statistical analysis. The Wilcoxon test was used to test the differences between the 2 maneuvers. Similar values were observed when comparing the LHA of the PFM at rest (12.2 ± 2.4) cm and during the AHT (11.7 ± 2.6) cm (P = 0.227). The AHT+ PFMC (10.2 ± 1.9) cm demonstrated lower values compared with AHT alone (11.7 ± 2.6) cm (P = 0.002). When comparing the PFMC (10.4 ± 2.1) cm with the AHT + PFMC (10.2 ± 1.9) cm, no significant difference (P = 0.551) was observed. During PFMC, the constriction was 1.8 cm; during the AHT, the constriction was 0.5 cm; and during the AHT + PFMC, it was 2 cm. The LHA assessed by 3-dimensional ultrasound did not significantly change with AHT. These results support the theory that AHT does not strengthen PFM.

  12. Two-photon photoacoustics ultrasound measurement by a loss modulation technique

    NASA Astrophysics Data System (ADS)

    Lai, Yu-Hung; Chang, Chieh-Feng; Cheng, Yu-Hsiang; Sun, Chi-Kuang

    2013-03-01

    In this work, we investigated the principle of the two-photon absorption (TPA) detection with a loss modulation technique, and first demonstrated the existence of two-photon photoacoustics ultrasound excited by a femtosecond high repetition rate laser. By using the AO modulation with different modulation frequencies, we successfully create the beating of the light signal when the two arms of the beams are both spatial and temporal overlapping. The pulse train of the femtosecond laser causes the narrow band excitation, providing the frequency selectivity and sensitivity. Moreover, the pulse energy is no more than 15nJ/pulse, which is at least 3 orders of magnitude smaller than that of the nanosecond laser, and therefore prevents the thermal damage of the sample. With the help of lock-in detection and a low noise amplifier, we can separate the signal of two-photon absorption from one-photon absorption. We used an ultrasonic transducer to detect the response of the sample, and verified the existence of the two-photon photoacoustics ultrasound generating by the femtosecond laser. Several contrast agents, such as the black carbon solution, the fluorescence dye and the nano-particles, were used in the experiment. In the end, we demonstrated the application, two photo-acoustic imaging, which provides the high spatial resolution (<10μm) and large penetration depth (~1mm), to the simulated biological tissue. This is a milestone to develop the two-photon photoacoustics microscopy, which, in principle, has the great potential to achieve the in vitro and in vivo high resolution deep tissue imaging.

  13. Procedural ultrasound in pediatric patients: techniques and tips for accuracy and safety.

    PubMed

    Lin, Sophia

    2016-06-01

    Point-of-care ultrasound is becoming more prevalent in pediatric emergency departments as a critical adjunct to both diagnosis and procedure guidance. It is cost-effective, safe for unstable patients, and easily repeatable as a patient's clinical status changes. Point-of-care ultrasound does not expose the patient to ionizing radiation and may care ultrasound in pediatric emergency medicine is relatively new, the body of literature evaluating its utility is small, but growing. Data from adult emergency medicine, radiology, critical care, and anesthesia evaluating the utility of ultrasound guidance must be extrapolated to pediatric emergency medicine. This issue will review the adult literature and the available pediatric literature comparing ultrasound guidance to more traditional approaches. Methods for using ultrasound guidance to perform various procedures, and the pitfalls associated with each procedure, will also be described.

  14. A technique for evaluating the oil/heavy-oil viscosity changes under ultrasound in a simulated porous medium.

    PubMed

    Hamidi, Hossein; Mohammadian, Erfan; Junin, Radzuan; Rafati, Roozbeh; Manan, Mohammad; Azdarpour, Amin; Junid, Mundzir

    2014-02-01

    Theoretically, Ultrasound method is an economical and environmentally friendly or "green" technology, which has been of interest for more than six decades for the purpose of enhancement of oil/heavy-oil production. However, in spite of many studies, questions about the effective mechanisms causing increase in oil recovery still existed. In addition, the majority of the mechanisms mentioned in the previous studies are theoretical or speculative. One of the changes that could be recognized in the fluid properties is viscosity reduction due to radiation of ultrasound waves. In this study, a technique was developed to investigate directly the effect of ultrasonic waves (different frequencies of 25, 40, 68 kHz and powers of 100, 250, 500 W) on viscosity changes of three types of oil (Paraffin oil, Synthetic oil, and Kerosene) and a Brine sample. The viscosity calculations in the smooth capillary tube were based on the mathematical models developed from the Poiseuille's equation. The experiments were carried out for uncontrolled and controlled temperature conditions. It was observed that the viscosity of all the liquids was decreased under ultrasound in all the experiments. This reduction was more significant for uncontrolled temperature condition cases. However, the reduction in viscosity under ultrasound was higher for lighter liquids compare to heavier ones. Pressure difference was diminished by decreasing in the fluid viscosity in all the cases which increases fluid flow ability, which in turn aids to higher oil recovery in enhanced oil recovery (EOR) operations. Higher ultrasound power showed higher liquid viscosity reduction in all the cases. Higher ultrasound frequency revealed higher and lower viscosity reduction for uncontrolled and controlled temperature condition experiments, respectively. In other words, the reduction in viscosity was inversely proportional to increasing the frequency in temperature controlled experiments. It was concluded that cavitation

  15. Optical detection of ultrasound using AFC-based quantum memory technique in cryogenic rare earth ion doped crystals

    NASA Astrophysics Data System (ADS)

    Taylor, Luke R.; McAuslan, David L.; Longdell, Jevon J.

    2013-03-01

    We present results of a novel and highly sensitive technique for the optical detection of ultrasound using the selective storage of frequency shifted photons in an inherently highly efficient and low noise atomic frequency comb (AFC) based quantum memory. The ultrasound `tagged' optical sidebands are absorbed within a pair of symmetric AFCs, generated via optical pumping in a Pr3+:Y2SiO5 sample (tooth separation Δ = 150 kHz, comb finesse fc ~ 2 and optical depth αL ~ 2), separated by twice the ultrasound modulation frequency (1.5 MHz) and centered on either side of a broad spectral pit (1.7 MHz width) allowing transmission of the carrier. The stored sidebands are recovered with 10-20% efficiency as a photon echo (as defined by the comb parameters), and we demonstrate a record 49 dB discrimination between the sidebands and the carrier pulse, high discrimination being important for imaging tissues at depth. We further demonstrate detector limited discrimination (~29 dB) using a highly scattered beam, confirming that the technique is immune to speckle decorrelation. We show that it also remains valid in the case of optically thin samples, and thus represents a significant improvement over other ultrasound detection methods based on rare-earth-ion-doped crystals. These results strongly suggest the suitability of our technique for high-resolution non-contact real-time imaging of biological tissues.

  16. A Computer-Controlled Ultrasound Pulser-Receiver System for Transkull Fluid Detection using a Shear Wave Transmission Technique

    PubMed Central

    Tang, Sai Chun; Clement, Gregory T.; Hynynen, Kullervo

    2007-01-01

    The purpose of this study was to evaluate the performance of a computer-controlled ultrasound pulser-receiver system incorporating a shear mode technique for transkull fluid detection. The presence of fluid in the sinuses of an ex vivo human was examined using pulse-echo method by transmitting an ultrasound beam through the maxilla bone towards the back wall on the other side of the sinus cavity. The pulser was programmed to generate bipolar pulse trains with 5 cycles, at frequency of 1MHz, repetition frequency of about 20Hz, and amplitude of 100V to drive a 1MHz piezoelectric transducer. Shear and longitudinal waves in the maxilla bone were produced by adjusting the bone surface incident angle to 45° and 0°, respectively. CT scans of the skull were performed to verify the ultrasound experiment. Using the shear mode technique, the echo waveform clearly distinguishes the presence of fluid, and the estimated distance of the ultrasound traveled in the sinus is consistent with the measurement from the CT images. Contrarily, using the longitudinal mode, no detectable back wall echo was observed under the same condition. As a conclusion, this study demonstrated that the proposed pulser-receiver system with the shear mode technique is promising for transkull fluid detecting, such as mucous in sinus. PMID:17941383

  17. Thermal dependence of ultrasound contrast agents scattering efficiency for echographic imaging techniques

    NASA Astrophysics Data System (ADS)

    Biagioni, Angelo; Bettucci, Andrea; Passeri, Daniele; Alippi, Adriano

    2015-06-01

    Ultrasound contrast agents are used in echographic imaging techniques to enhance image contrast. In addition, they may represent an interesting solution to the problem of non-invasive temperature monitoring inside the human body, based on some thermal variations of their physical properties. Contrast agents, indeed, are inserted into blood circulation and they reach the most important organs inside the human body; consequently, any thermometric property that they may possess, could be exploited for realizing a non-invasive thermometer. They essentially are a suspension of microbubbles containing a gas enclosed in a phospholipid membrane; temperature variations induce structural modifications of the microbubble phospholipid shell, thus causing thermal dependence of contrast agent's elastic characteristics. In this paper, the acoustic scattering efficiency of a bulk suspension of of SonoVue® (Bracco SpA Milan, Italy) has been studied using a pulse-echo technique in the frequency range 1-17 MHz, as it depends upon temperatures between 25 and 65°C. Experimental data confirm that the ultrasonic attenuation coefficient of SonoVue® depends on temperature between 25 and 60°C. Chemical composition of the bubble shell seem to support the hypothesis that a phase transition in the microstructure of lipid-coated microbubbles could play a key role in explaining such effect.

  18. Ultrasound submucosal inferior nasal turbinate reduction technique: histological study of wound healing in a sheep model.

    PubMed

    Nousia, Christina; Gouveris, Haralampos; Giatromanolaki, Alexandra; Ypsilantis, Petros; Katotomichelakis, Michael; Watelet, Jean-Baptiste; Simopoulos, Konstantinos; Danielides, Vassilios

    2010-06-01

    To describe histological changes after application of an ultrasound tissue reduction (UTR) technique in a newly introduced sheep model to study inferior nasal turbinate mucosal wound healing. An experimental study in a sheep model. Stromal fibrosis, submucosal interstitial space volume (ISV), mucosal epithelial cell necrosis, mucosal inflammation and blood vessels' engorgement in inferior turbinate samples were assessed after application of UTR using hematoxylin/eosin staining in 12 turbinate samples after different time points. Histological grading was performed using a 4-point scale After one week, extensive development of fibrosis (p = 0.006) and significant reduced stromal ISV (p < 0.001) compared to controls were observed. The degree of fibrosis and the stromal ISV remained constant during the 8-week period. The extensive epithelial cell necrosis observed at week 1, diminished later, so that at 8 weeks no significant difference with controls in the necrosis extent was noted. Significant reduction of engorgement of blood vessels in the submucosal layer was noted after 8 weeks (p = 0.008, compared with baseline). Mucosal inflammation, while pronounced at week 1 (p = 0.005, compared with baseline), was normalized at week 8. Due to the rapid induction of extensive fibrosis, to the limited inflammation reaction, to the moderate degree of epithelial necrosis, to the reduction of subepithelial ISV and the persistence of these features till week 8 at least, UTR emerges as an effective minimally invasive technique for inferior nasal turbinate volume reduction.

  19. Traditional endodontic surgery versus modern technique: a 5-year controlled clinical trial.

    PubMed

    Tortorici, Silvia; Difalco, Paolo; Caradonna, Luigi; Tetè, Stefano

    2014-05-01

    In this study, we compared outcomes of traditional apicoectomy versus modern apicoectomy, by means of a controlled clinical trial with a 5-year follow-up. The study investigated 938 teeth in 843 patients. On the basis of the procedure performed, the teeth were grouped in 3 groups. Differences between the groups were the method of osteotomy (type of instruments used), type of preparation of retrograde cavity (different apicoectomy angles and instruments used for root-end preparation), and root-end filling material used (gray mineral trioxide aggregate or silver amalgam). Outcome (tooth healing) was estimated after 1 and 5 years, postoperatively. Clinical success rates after 1 year were 67% (306 teeth), 90% (186 teeth), and 94% (256 teeth) according to traditional apicoectomy (group 1), modern microsurgical apicoectomy using burns for osteotomy (group 2) or using piezo-osteotomy (group 3), respectively. After 1 year, group comparison results were statistically significant (P < 0.0001). Linear trend test was also statistically significant (P < 0.0001), pointing out larger healing from group 1 to group 3. After 5 years, teeth were classified into 2 groups on the basis of root-end filling material used. Clinical success was 90.8% (197 teeth) in the silver amalgam group versus 96% (309 teeth) in the mineral trioxide aggregate group (P < 0.00214). Multiple logistic regression analysis found that surgical technique was independently associated to tooth healing. In conclusion, modern apicoectomy resulted in a probability of success more than 5 times higher (odds ratio, 5.20 [95% confidence interval, 3.94-6.92]; P < 0.001) compared with the traditional technique.

  20. Do Anesthetic Techniques Influence the Threshold for Glomerular Capillary Hemorrhage induced in Rats by Contrast Enhanced Diagnostic Ultrasound?

    PubMed Central

    Miller, Douglas L.; Lu, Xiaofang; Fabiilli, Mario; Dou, Chunyan

    2016-01-01

    Objectives Glomerular capillary hemorrhage (GCH) can be induced by ultrasonic cavitation during contrast enhanced diagnostic ultrasound (CEDUS), an important nonthermal ultrasound bioeffect. Recent studies of pulmonary ultrasound exposure have shown that thresholds for another nonthermal bioeffect of ultrasound, pulmonary capillary hemorrhage, is strongly influenced by whether or not xylazine is included in the specific anesthetic technique. Methods In this study, anesthesia with ketamine only was compared to ketamine plus xylazine for the induction of GCH in rats by 1.6 MHz intermittent diagnostic ultrasound with contrast agent (similar to Definity). GCH was measured as a percentage of glomeruli with hemorrhage found in histological sections for groups of rats scanned at different peak rarefactional pressure amplitudes. Results There was a significant difference between the magnitude of the GCH between the two anesthetics at 2.3 MPa with 45.6 % GCH for ketamine only, increasing to 63.2 % GCH for ketamine plus xylazine anesthesia (P<0.001). However, the thresholds for the two anesthesia methods were virtually identical at 1.0 MPa, based on linear regression of the exposure response data. Conclusions Therefore, thresholds for CEDUS induced injury of the microvasculature appears to be minimally affected by anesthesia methods. PMID:26764276

  1. Ultrasound-guided central venous catheterization: A review of the relevant anatomy, technique, complications, and anatomical variations.

    PubMed

    Hoffman, Taryn; Du Plessis, Maira; Prekupec, Matthew P; Gielecki, Jerzy; Zurada, Anna; Shane Tubbs, R; Loukas, Marios

    2017-03-01

    Central venous catheterization is a commonly used and important intervention. Despite its regular use it is still associated with a high incidence of complications especially infection and catheter tip embolization. Addition of ultrasound guidance to the technique has shown great improvement to the time and number of attempts for successful catheterization. The preference of vein depends greatly on the situation; subclavian vein is the preferred method overall but internal jugular vein is preferred in patients undergoing cardiac or thoracic surgery. This is especially true for pediatric patients in whom femoral vein catheterization is still preferred despite it carrying a higher risk than other locales. Addition of ultrasound guidance greatly reduces the incidence of arterial puncture and subsequent hematoma formation regardless of location. This is because it allows for visualization of anatomical variation prior to intervention and continual visualization of the needle during the placement. It is noteworthy however, that addition of ultrasound does not prevent complications such as catheter tip embolization as this may occur even with perfect placement. The value of ultrasound usage is undisputable since all studies assessing the difference between it and landmark based methods showed preferable outcome. Reduction of time and number of attempts is sufficient argument to make ultrasound guidance standard practice. Clin. Anat. 30:237-250, 2017. © 2017 Wiley Periodicals, Inc.

  2. Power ultrasound-assisted cleaner leather dyeing technique: influence of process parameters.

    PubMed

    Sivakumar, Venkatasubramanian; Rao, Paruchuri Gangadhar

    2004-03-01

    The application of power ultrasound to leather processing has a significant role in the concept of "clean technology" for leather production. The effect of power ultrasound in leather dyeing has been compared with dyeing in the absence of ultrasound and conventional drumming. The power ultrasound source used in these experiments was ultrasonic cleaner (150 W and 33 kHz). The effect of various process parameters such as amount of dye offer, temperature, and type of dye has been experimentally found out. The effect of presonication of dye solution as well as leather has been studied. Experiments at ultrasonic bath temperature were carried out to find out the combined thermal as well as stirring effects of ultrasound. Dyeing in the presence of ultrasound affords about 37.5 (1.8 times) difference as increase in % dye exhaustion or about 50% decrease in the time required for dyeing compared to dyeing in the absence of ultrasound for 4% acid red dye. About 29 (1.55 times) increase in % dye exhaustion or 30% reduction in time required for dyeing was observed using ultrasound at stationary condition compared with conventional dynamic drumming conditions. The effect of ultrasound at constant temperature conditions with a control experiment has also been studied. The dye exhaustion increases as the temperature increases (30-60 degrees C) and better results are observed at higher temperature due to the use of ultrasound. Presonication of dye solution or crust leather prior to the dyeing process has no significant improvement in dye exhaustion, suggesting ultrasound effect is realized when it is applied during the dyeing process. The results indicate that 1697 and 1416 ppm of dye can be reduced in the spent liquor due to the use of ultrasound for acid red (for 100 min) and acid black (for 3 h) dyes, respectively, thereby reducing the pollution load in the effluent stream. The color yield of the leather as inferred from the reflectance measurement indicates that dye offer can

  3. Continuous independent quality control for fetal ultrasound biometry provided by the cumulative summation technique.

    PubMed

    Balsyte, D; Schäffer, L; Burkhardt, T; Wisser, J; Zimmermann, R; Kurmanavicius, J

    2010-04-01

    To apply the cumulative summation (CUSUM) technique for an evaluation of the learning process of sonographic fetal weight estimation at term in combination with the z-scores of biometry determinants and to assess the time of appearance and sources of errors. Learning curve (LC-CUSUM) and double CUSUM charts for systematic error detection based on absolute and signed mean percentage error were generated to retrospectively estimate the longitudinal accuracy of sonographic fetal weight estimation conducted by three trainees and one experienced examiner. For LC-CUSUM analysis an examination was considered to be a failure when there was an absolute error in birth weight estimation >/= 15%. Fetal biometry measurements (head circumference, abdominal circumference (AC) and femur length (FL)) from 227 routine ultrasound scans of one examiner were separately transformed into z-scores and double CUSUM charts were generated to assess the systematic errors for each determinant. The LC-CUSUM charts revealed that different numbers of scans are required for different examiners to achieve competence in estimating birth weight. AC and FL deviated most significantly from expected values (P < 0.05). The double CUSUM charts revealed exact periods of systematic errors in the measurement of biometry determinants, clearly reflecting errors of fetal weight estimation. The use of CUSUM techniques in the analysis of sonographic data allows observation of the development of an examiner's skill and maintenance of competence. The CUSUM technique not only allows the reasons for impaired fetal weight estimation to be revealed but also allows determination of the exact time when inaccurate measurements start to occur. We suggest that CUSUM charts should be implemented in routine clinical practice as a measure of objective quality evaluation of sonographic fetal biometry. Copyright 2009 ISUOG. Published by John Wiley & Sons, Ltd.

  4. The Imaging Modulography Technique Revisited for High-Definition Intravascular Ultrasound: Theoretical Framework.

    PubMed

    Tacheau, Antoine; Le Floc'h, Simon; Finet, Gérard; Doyley, Marvin M; Pettigrew, Roderic I; Cloutier, Guy; Ohayon, Jacques

    2016-03-01

    Mechanical characterization of atherosclerotic lesions remains an essential step for the detection of vulnerable plaques (VPs). Recently, an intravascular ultrasound (IVUS) elasticity reconstruction method (iMOD) has been tested in vivo by our group. The major limitation of iMOD is the need to estimate the strain field in the entire VP despite attenuated depth penetration signals when using high-definition (HD) IVUS systems. Therefore, an extended iMOD approach (E-iMOD) was designed and applied to coronary lesions of patients imaged in vivo with IVUS. The E-iMOD method (i) quantified necrotic core areas with a mean absolute relative error of 3.5 ± 3.5% and (ii) identified Young's moduli of the necrotic cores and fibrous regions with mean values of 5.7 ± 0.8 kPa and 794.5 ± 22.0 kPa instead of 5 kPa and 800 kPa, respectively. This study demonstrates the potential of the improved HD-IVUS modulography technique E-iMOD to characterize coronary VPs.

  5. 3D dynamic model of healthy and pathologic arteries for ultrasound technique evaluation.

    PubMed

    Balocco, Simone; Basset, Olivier; Azencot, Jacques; Tortoli, Piero; Cachard, Christian

    2008-12-01

    A 3D model reproducing the biomechanical behavior of human blood vessels is presented. The model, based on a multilayer geometry composed of right generalized cylinders, enables the representation of different vessel morphologies, including bifurcations, either healthy or affected by stenoses. Using a finite element approach, blood flow is simulated by considering a dynamic displacement of the scatterers (erythrocytes), while arterial pulsation due to the hydraulic pressure is taken into account through a fluid-structure interaction based on a wall model. Each region is acoustically characterized using FIELD II software, which produces the radio frequency echo signals corresponding to echographic scans. Three acoustic physiological phantoms of carotid arteries surrounded by elastic tissue are presented to illustrate the model's capability. The first corresponds to a healthy blood vessel, the second includes a 50% stenosis, and the third represents a carotid bifurcation. Examples of M mode, B mode and color Doppler images derived from these phantoms are shown. Two examples of M-mode image segmentation and the identification of the atherosclerotic plaque boundaries on Doppler color images are reported. The model could be used as a tool for the preliminary evaluation of ultrasound signal processing and visualization techniques.

  6. Air-coupled ultrasound: a novel technique for monitoring the curing of thermosetting matrices.

    PubMed

    Lionetto, Francesca; Tarzia, Antonella; Maffezzoli, Alfonso

    2007-07-01

    A custom-made, air-coupled ultrasonic device was applied to cure monitoring of thick samples (7-10 mm) of unsaturated polyester resin at room temperature. A key point was the optimization of the experimental setup in order to propagate compression waves during the overall curing reaction by suitable placement of the noncontact transducers, placed on the same side of the test material, in the so-called pitch-catch configuration. The progress of polymerization was monitored through the variation of the time of flight of the propagating longitudinal waves. The exothermic character of the polymerization was taken into account by correcting the measured value of time of flight with that one in air, obtained by sampling the air velocity during the experiment. The air-coupled ultrasonic results were compared with those obtained from conventional contact ultrasonic measurements. The good agreement between the air-coupled ultrasonic results and those obtained by the rheological analysis demonstrated the reliability of air-coupled ultrasound in monitoring the changes of viscoelastic properties at gelation and vitrification. The position of the transducers on the same side of the sample makes this technique suitable for on-line cure monitoring during several composite manufacturing technologies.

  7. Randomized controlled trial of ultrasound-guided peripheral intravenous catheter placement versus traditional techniques in difficult-access pediatric patients.

    PubMed

    Doniger, Stephanie J; Ishimine, Paul; Fox, John Christian; Kanegaye, John T

    2009-03-01

    We hypothesized that the use of ultrasound guidance would improve the success rate of peripheral intravenous catheter placement in pediatric patients with difficult access in a pediatric emergency department (ED). Our secondary hypotheses were that ultrasound guidance would reduce the number of attempts, the number of needle redirections, and the overall time to catheter placement. This was a prospective randomized study of pediatric ED patients younger than 10 years old requiring intravenous access, presenting between August 2006 and May 2007. Inclusion criteria were 2 unsuccessful traditional attempts at peripheral intravenous access or history of difficult access. Exclusion was critical illness or instability. Patients were randomized to undergo peripheral intravenous catheter placement using continued traditional approaches or real-time, dual-operator ultrasound-guided technique. Measured outcomes were success of cannulation, number of attempts, number of needle redirections, and overall time to catheter placement. Fifty patients were enrolled, with 25 patients randomized to each group. The overall success rates for the ultrasound-guided group were 80% and for the traditional-attempts group, 64%, with a difference in proportions of 16% (95% confidence interval, -9% to 38%, P = 0.208). The ultrasound-guided group required less overall time (6.3 vs 14.4 minutes, difference of -8.1 minutes [95% confidence interval, -12.5 to -3.6], P = 0.001), fewer attempts (median, 1 vs 3; P = 0.004), and fewer needle redirections (median, 2 vs 10; P G 0.0001) than traditional approaches. In a sample of pediatric ED patients with difficult access, ultrasound-guided intravenous cannulation required less overall time, fewer attempts, and fewer needle redirections than traditional approaches.

  8. Breast Ultrasound: Indications and Findings.

    PubMed

    Gundry, Kathleen R

    2016-06-01

    Breast ultrasound is a widely used adjuvant to mammography for the detection of breast cancer. This chapter will review some of the basic ultrasound technical factors and techniques, describe findings on ultrasound with an emphasis on the Breast Imaging Reporting and Data System terminology, and present the indications for breast ultrasound. New innovations in breast ultrasound, such as elastography, ultrasound contrast, 3-dimensional, and automated whole-breast ultrasound, will be reviewed. Ultrasound-guided breast procedures are also presented.

  9. Standardization of a compound Unani herbal formulation “Qurs-e-Luk” with modern techniques

    PubMed Central

    Rasheed, N. M. A.; Gupta, V. C.

    2010-01-01

    Background: With global realization that use of synthetic drugs is not safe on the long run, the medical fraternity at large is looking at alternatives from natural sources to combat diseases particularly those wherein conventional modern system of medicine has little to offer. On one hand, this realization has increased demand for herbal drugs and on the other hand need for quality standardization of these drugs has increased. Central Research Institute of Unani Medicine, Hyderabad, being engaged in multidisciplinary research in Unani Medicine, has taken up standardization of herbomineral drugs used in this system of medicine. One such drug “Qurs-e-Luk” that is widely used by the practitioners of this system in mobilizing and reducing body fat has been utilized for standardization by modern techniques, so as to ascertain its quality. Methods: The parameters which were carried out are pharmacognostic studies, physicochemical parameters, high-performance thin layer chromatography, microbial load, aflatoxins, heavy metals, and pesticidal residues revealing specific identities for the particular drug and to evaluate pharmacopoeial standards. Results and Conclusion: Results suggest that the drug is safe for therapeutic use and its batch to batch identification for quality control is possible on the basis of present study. PMID:21808574

  10. Accuracy and sampling error of two age estimation techniques using rib histomorphometry on a modern sample.

    PubMed

    García-Donas, Julieta G; Dyke, Jeffrey; Paine, Robert R; Nathena, Despoina; Kranioti, Elena F

    2016-02-01

    Most age estimation methods are proven problematic when applied in highly fragmented skeletal remains. Rib histomorphometry is advantageous in such cases; yet it is vital to test and revise existing techniques particularly when used in legal settings (Crowder and Rosella, 2007). This study tested Stout & Paine (1992) and Stout et al. (1994) histological age estimation methods on a Modern Greek sample using different sampling sites. Six left 4th ribs of known age and sex were selected from a modern skeletal collection. Each rib was cut into three equal segments. Two thin sections were acquired from each segment. A total of 36 thin sections were prepared and analysed. Four variables (cortical area, intact and fragmented osteon density and osteon population density) were calculated for each section and age was estimated according to Stout & Paine (1992) and Stout et al. (1994). The results showed that both methods produced a systemic underestimation of the individuals (to a maximum of 43 years) although a general improvement in accuracy levels was observed when applying the Stout et al. (1994) formula. There is an increase of error rates with increasing age with the oldest individual showing extreme differences between real age and estimated age. Comparison of the different sampling sites showed small differences between the estimated ages suggesting that any fragment of the rib could be used without introducing significant error. Yet, a larger sample should be used to confirm these results.

  11. Improved image guidance technique for minimally invasive mitral valve repair using real-time tracked 3D ultrasound

    NASA Astrophysics Data System (ADS)

    Rankin, Adam; Moore, John; Bainbridge, Daniel; Peters, Terry

    2016-03-01

    In the past ten years, numerous new surgical and interventional techniques have been developed for treating heart valve disease without the need for cardiopulmonary bypass. Heart valve repair is now being performed in a blood-filled environment, reinforcing the need for accurate and intuitive imaging techniques. Previous work has demonstrated how augmenting ultrasound with virtual representations of specific anatomical landmarks can greatly simplify interventional navigation challenges and increase patient safety. These techniques often complicate interventions by requiring additional steps taken to manually define and initialize virtual models. Furthermore, overlaying virtual elements into real-time image data can also obstruct the view of salient image information. To address these limitations, a system was developed that uses real-time volumetric ultrasound alongside magnetically tracked tools presented in an augmented virtuality environment to provide a streamlined navigation guidance platform. In phantom studies simulating a beating-heart navigation task, procedure duration and tool path metrics have achieved comparable performance to previous work in augmented virtuality techniques, and considerable improvement over standard of care ultrasound guidance.

  12. Variability of Liver Shear Wave Measurements Using a New Ultrasound Elastographic Technique.

    PubMed

    Nadebaum, David P; Nicoll, Amanda J; Sood, Siddharth; Gorelik, Alexandra; Gibson, Robert N

    2017-09-29

    A new 2-dimensional (2D) shear wave elastographic (SWE) device has been developed for the noninvasive assessment of liver fibrosis. Guidelines on measurement acquisition parameters are not yet well established for this technique. Our study aimed to assess 2D SWE measurement variability and to determine the number of measurements required per patient to reliably assess liver stiffness. Two-dimensional SWE was assessed in 55 patients with mixed-etiology chronic liver disease on an Aplio 500 ultrasound system (Toshiba Medical Systems Corporation, Tochigi, Japan). Ten measurements were obtained per patient by an operator blinded to all preceding readings. Results were analyzed with clinical information obtained from medical records. The median interquartile range/median ratio for 2D SWE was 0.131 (quartiles 1-3, 0.089-0.174). Five readings provided an approximation within 0.11 m/s, or 4.2% of the median velocity of 10 measurements. Factors associated with increased measurement variability included body mass index (ρ = 0.388; P = .01), increased skin-to-liver capsule distance (ρ = 0.426; P = .002), and measurements taken within 1.5 cm of the liver capsule (P < .001). Measurements with heterogeneous shear wave profiles (indicated by a region of interest [ROI] SD/speed ratio > 0.15) showed greater deviation from the set's median velocity than those with an ROI SD/speed ratio of 0.15 or lower (0.42 versus 0.22 m/s; P = .001). Two-dimensional SWE showed low overall measurement variability, with a minimum of 5 readings providing equivalent precision to the existing method using 10 samples. Obesity, increasing abdominal wall thickness, subcapsular measurements and an ROI SD/speed ratio of greater than 0.15 were all associated with increased measurement variability. The ROI SD/speed ratio warrants further evaluation as a quality assessment metric, to allow objective operator assessment of individual 2D SWE measurement reliability in real

  13. Modern control techniques in active flutter suppression using a control moment gyro

    NASA Technical Reports Server (NTRS)

    Buchek, P. M.

    1974-01-01

    Development of organized synthesis techniques, using concepts of modern control theory was studied for the design of active flutter suppression systems for two and three-dimensional lifting surfaces, utilizing a control moment gyro (CMG) to generate the required control torques. Incompressible flow theory is assumed, with the unsteady aerodynamic forces and moments for arbitrary airfoil motion obtained by using the convolution integral based on Wagner's indicial lift function. Linear optimal control theory is applied to find particular optimal sets of gain values which minimize a quadratic performance function. The closed loop system's response to impulsive gust disturbances and the resulting control power requirements are investigated, and the system eigenvalues necessary to minimize the maximum value of control power are determined.

  14. Modern techniques for the determination of anabolic-androgenic steroid doping in the horse.

    PubMed

    McKinney, Andrew R

    2009-07-01

    Control of the use of performance-affecting substances in the horse is critical to the integrity of a wide range of equine sports, with major implications for both animal welfare and revenue streams. One class of medications enjoying particular public notoriety is the anabolic-androgenic steroid group, as highlighted by the recent 'Big Brown' affair and Congressional inquiries into the use of steroids in professional sports, including horse racing, in the USA. This review examines the latest developments pertaining to the analytical detection of these substances in equine biological samples and the supporting regulatory environment. Consideration is given to the full variety of sample matrices available, together with modern sample preparative approaches and instrumental techniques. Issues concerning the regulation of endogenous steroids, including thresholds where applicable, are also discussed.

  15. Evaluation of an ultrasound-guided technique for axillary brachial plexus blockade in cats.

    PubMed

    Ansón, Agustina; Laredo, Francisco G; Gil, Francisco; Soler, Marta; Belda, Eliseo; Agut, Amalia

    2017-02-01

    Objectives The aim of this study was to evaluate and refine an ultrasound (US)-guided technique to block the brachial plexus (BP) at the level of the axillary space in live cats. Methods Eight adult experimental cats were enrolled into the study. The animals were sedated and positioned in dorsal recumbency with the limb to be blocked abducted 90º. The US transducer was placed in the axillary region and a non-traumatic peripheral nerve block needle was inserted in-plane with respect to the transducer, medial to the BP up to the level of the axillary artery. Lidocaine 1% (0.4 ml/kg) was injected as the needle was being progressively withdrawn in a caudal-to-cranial direction. The efficacy of the block was confirmed by evaluation of the motor and sensory functions of the blocked forelimb. Motor blockade was assessed observing the position of the blocked leg on standing and walking patterns. Sensory blockade was evaluated by the stimulation of mechanical nociceptors in the dermatomes supplied by the four major sensory nerves of the distal thoracic limb. Results The BP was successfully located by US in all cases. The achieved BP block was complete in six cats (75%) and partial in the remaining two cats (25%). All animals recovered uneventfully from the sedation and the BP blocks. Conclusions and relevance The US-guided block at the axillary space evaluated in this study is a feasible, reproducible and safe technique to block the BP plexus in experimental live cats.

  16. Computed tomography-ultrasound fusion brachytherapy: description and evolution of the technique.

    PubMed

    Fuller, Donald B; Jin, Haoran

    2007-01-01

    In this manuscript, we describe our computed tomography (CT)-ultrasound (US) fusion prostate brachytherapy method and report the updated dosimetry result and trend. This cohort of 132 consecutive patients received CT-US fusion prostate brachytherapy from the first author (DBF) from December 2002 to August 2006. The technique consists of a hybrid preplanned and intraoperative dynamic dosimetry method, which initially delivers a standard preplanned source distribution, and then uses interval CT-based source identification dosimetry, fused to an identically spaced intraoperative US volume study series, to direct remedial sources that correct initial dosimetry deficiencies. The median and minimum prostate Day 0 prostate volume of interest receiving 100% of prescribed dose (V(100)) results in this patient cohort measured 98.26% and 92.61%, respectively, with all Day 0 prostate dose received by 90% of the volume of interest (D(90)) results exceeding 100% of the prescribed dose, and the maximum Day 0 prostate D(90) value measuring 128% of the prescribed dose. During the period of this analysis, a trend to the decreased quantity of dynamic remedial millicuries per case was identified, with the total sources decreasing from 116% to 106% of the preplanned level, resulting in minimal V(100) and D(90) decreases, while continuing to exceed the minimum Day 0 dosimetry requirements. CT-US fusion dynamic prostate brachytherapy represents a consistent prostate brachytherapy dosimetry delivery mechanism, creating a tight lower and upper bound to the final Day 0 prostate V(100) and D(90) parameters. The practice and pitfalls of this technique are discussed in detail.

  17. 20th International Conference for Students and Young Scientists: Modern Techniques and Technologies (MTT'2014)

    NASA Astrophysics Data System (ADS)

    2014-10-01

    The active involvement of young researchers in scientific processes and the acquisition of scientific experience by gifted youth currently have a great value for the development of science. One of the research activities of National Research Tomsk Polytechnic University, aimed at the preparing and formation of the next generation of scientists, is the International Conference of Students and Young Scientists ''Modern Techniques and Technologies'', which was held in 2014 for the twentieth time. Great experience in the organization of scientific events has been acquired through years of carrying the conference. There are all the necessary resources for this: a team of organizers - employees of Tomsk Polytechnic University, premises provided with modern office equipment and equipment for demonstration, and leading scientists - professors of TPU, as well as the status of the university as a leading research university in Russia. This way the conference is able to attract world leading scientists for the collaboration. For the previous years the conference proved itself as a major scientific event at international level, which attracts more than 600 students and young scientists from Russia, CIS and other countries. The conference provides oral plenary and section reports. The conference is organized around lectures, where leading Russian and foreign scientists deliver plenary presentations to young audiences. An important indicator of this scientific event is the magnitude of the coverage of scientific fields: energy, heat and power, instrument making, engineering, systems and devices for medical purposes, electromechanics, material science, computer science and control in technical systems, nanotechnologies and nanomaterials, physical methods in science and technology, control and quality management, design and technology of artistic materials processing. The main issues considered by young researchers at the conference were related to the analysis of contemporary

  18. Ultrasound-Guided Trigger Point Injection for Serratus Anterior Muscle Pain Syndrome: Description of Technique and Case Series.

    PubMed

    Vargas-Schaffer, Grisell; Nowakowsky, Michal; Eghtesadi, Marzieh; Cogan, Jennifer

    2015-09-15

    Chronic chest pain is a challenge, and serratus anterior muscle pain syndrome (SAMPS) is often overlooked. We have developed an ultrasound-guided technique for infiltrating local anesthetics and steroids in patients with SAMPS. In 8 patients, the duration of chronic pain was approximately 19 months. Three months after treatment, all patients had experienced a significant reduction in pain. Infiltration for SAMPS confirms the diagnosis and provides adequate pain relief.

  19. Clinical effect of peripherally inserted central catheters based on modified seldinger technique under guidance of vascular ultrasound

    PubMed Central

    Wang, Qingguo; Wang, Ni; Sun, Yuzhen

    2016-01-01

    Objective: To observe and analyze the application effect of ultrasound-guided modified Seldinger technique (MST) in Peripherally Inserted Central Catheter (PICC) catheterization. Methods: Two hundred patients treated with PICC catheterization from January 2013 to December 2015 were selected and randomly divided into two groups, namely, observation group and control group. The observation group adopted ultrasound-guided MST for catheterization while the control group applied traditional puncture technique for catheterization. Then efficacy of catheterization, success rate of catheterization and incidence rates of complications were compared between two groups. Results: Various indicators of catheterization effects of the observation group were better than those of the control group, and the differences were statistically significant (P<0.05); one-time success rate of puncture and catheterization of the observation group was both higher than the control group (P<0.05);. Moreover, the incidence of puncture points bleeding, phlebitis and thrombus were all lower than those of the control group (P<0.05). Conclusion: Implementing PICC catheterization based on ultrasound-guided modified Seldinger puncture technique can increase success rate of puncture, improve the effect of catheterization, lower incidence rate of adverse effects of catheterization and improve satisfaction and comfort level of patients. PMID:27882017

  20. Comparison of three techniques for ultrasound-guided femoral nerve catheter insertion: A randomized, blinded trial

    PubMed Central

    Farag, Ehab; Atim, Abdulkadir; Ghosh, Raktim; Bauer, Maria; Sreenivasalu, Thilak; Kot, Michael; Kurz, Andrea; Dalton, Jarrod E.; Mascha, Edward J.; Mounir-Soliman, Loran; Zaky, Sherif; Esa, Wael Ali Sakr; Udeh, Belinda L.; Barsoum, Wael; Sessler, Daniel I.

    2014-01-01

    Background Ultrasound guidance for continuous femoral perineural catheters may be supplemented by electrical stimulation through a needle or through a stimulating catheter. We tested the primary hypothesis that ultrasound guidance alone is noninferior on both postoperative pain scores and opioid requirement and superior on at least one of the two. Secondarily, we compared all interventions on insertion time and incremental cost. Methods Patients having knee arthroplasty with femoral nerve catheters were randomly assigned to catheter insertion guided by: 1) ultrasound alone (n=147); 2) ultrasound and electrical stimulation through the needle (n=152); or, 3) ultrasound and electrical stimulation through both the needle and catheter (n=138). Noninferiority between any two interventions was defined for pain as no more than 0.5 points worse on a 0–10 Verbal Response Scale (VRS) scale and for opioid consumption as no more than 25% greater than the mean. Results The stimulating needle group was significantly noninferior to the stimulating catheter (difference (95% CI) in mean VRS pain score [stimulating needle versus stimulating catheter] of −0.16 (−0.61, 0.29), P<0.001; percent difference in mean IV morphine equivalent dose of −5% (−25%, 21%), P=0.002) and to ultrasound only (difference in mean VRS pain score of −0.28 (−0.72, 0.16), P<0.001; percent difference in mean IV morphine equivalent dose of −2% (−22%, 25%), P=0.006). In addition, the use of ultrasound alone for femoral nerve catheter insertion was faster and cheaper than the other two methods. Conclusion Ultrasound guidance alone without adding either stimulating needle or needle/catheter combination thus appears to be the best approach to femoral perineural catheters. PMID:24758775

  1. Involved-Node Radiotherapy and Modern Radiation Treatment Techniques in Patients With Hodgkin Lymphoma

    SciTech Connect

    Paumier, Amaury; Ghalibafian, Mithra; Beaudre, Anne; Ferreira, Ivaldo; Pichenot, Charlotte; Messai, Taha; Lessard, Nathalie Athalie; Lefkopoulos, Dimitri; Girinsky, Theodore

    2011-05-01

    Purpose: To assess the clinical outcome of the involved-node radiotherapy (INRT) concept using modern radiation treatments (intensity-modulated radiotherapy [IMRT]or deep-inspiration breath-hold radiotherapy [DIBH) in patients with localized supradiaphragmatic Hodgkin lymphoma. Methods and Materials: All but 2 patients had early-stage Hodgkin lymphoma, and they were treated with chemotherapy prior to irradiation. Radiation treatments were delivered using the INRT concept according to European Organization for Research and Treatment of Cancer guidelines. IMRT was performed with the patient free-breathing. For the adapted breath-hold technique, a spirometer dedicated to DIBH radiotherapy was used. Three-dimensional conformal radiotherapy was performed with those patients. Results: Fifty patients with Hodgkin lymphoma (48 patients with primary Hodgkin lymphoma, 1 patient with recurrent disease, and 1 patient with refractory disease) entered the study from January 2003 to August 2008. Thirty-two patients were treated with IMRT, and 18 patients were treated with the DIBH technique. The median age was 28 years (range, 17-62 years). Thirty-four (68%) patients had stage I - (I-IIA) IIA disease, and 16 (32%) patients had stage I - (I-IIB) IIB disease. All but 3 patients received three to six cycles of adriamycin, bleomycin, vinblastine, and dacarbazine (ABVD). The median radiation doses to patients treated with IMRT and DIBH were, respectively, 40 Gy (range, 21.6-40 Gy) and 30.6 Gy (range, 19.8-40 Gy). Protection of various organs at risk was satisfactory. Median follow-up was 53.4 months (range, 19.1-93 months). The 5-year progression-free and overall survival rates for the whole population were 92% (95% confidence interval [CI], 80%-97%) and 94% (95% CI, 75%-98%), respectively. Recurrences occurred in 4 patients: 2 patients had in-field relapses, and 2 patients had visceral recurrences. Grade 3 acute lung toxicity (transient pneumonitis) occurred in 1 case. Conclusions

  2. Advanced grazing-incidence techniques for modern soft-matter materials analysis.

    PubMed

    Hexemer, Alexander; Müller-Buschbaum, Peter

    2015-01-01

    The complex nano-morphology of modern soft-matter materials is successfully probed with advanced grazing-incidence techniques. Based on grazing-incidence small- and wide-angle X-ray and neutron scattering (GISAXS, GIWAXS, GISANS and GIWANS), new possibilities arise which are discussed with selected examples. Due to instrumental progress, highly interesting possibilities for local structure analysis in this material class arise from the use of micro- and nanometer-sized X-ray beams in micro- or nanofocused GISAXS and GIWAXS experiments. The feasibility of very short data acquisition times down to milliseconds creates exciting possibilities for in situ and in operando GISAXS and GIWAXS studies. Tuning the energy of GISAXS and GIWAXS in the soft X-ray regime and in time-of flight GISANS allows the tailoring of contrast conditions and thereby the probing of more complex morphologies. In addition, recent progress in software packages, useful for data analysis for advanced grazing-incidence techniques, is discussed.

  3. Advanced grazing-incidence techniques for modern soft-matter materials analysis

    PubMed Central

    Hexemer, Alexander; Müller-Buschbaum, Peter

    2015-01-01

    The complex nano-morphology of modern soft-matter materials is successfully probed with advanced grazing-incidence techniques. Based on grazing-incidence small- and wide-angle X-ray and neutron scattering (GISAXS, GIWAXS, GISANS and GIWANS), new possibilities arise which are discussed with selected examples. Due to instrumental progress, highly interesting possibilities for local structure analysis in this material class arise from the use of micro- and nanometer-sized X-ray beams in micro- or nanofocused GISAXS and GIWAXS experiments. The feasibility of very short data acquisition times down to milliseconds creates exciting possibilities for in situ and in operando GISAXS and GIWAXS studies. Tuning the energy of GISAXS and GIWAXS in the soft X-ray regime and in time-of flight GISANS allows the tailoring of contrast conditions and thereby the probing of more complex morphologies. In addition, recent progress in software packages, useful for data analysis for advanced grazing-incidence techniques, is discussed. PMID:25610632

  4. A comparison of the modern Lie scaling method to classical scaling techniques

    NASA Astrophysics Data System (ADS)

    Polsinelli, James; Kavvas, M. Levent

    2016-07-01

    In the past 2 decades a new modern scaling technique has emerged from the highly developed theory on the Lie group of transformations. This new method has been applied by engineers to several problems in hydrology and hydraulics, including but not limited to overland flow, groundwater dynamics, sediment transport, and open channel hydraulics. This study attempts to clarify the relationship this new technology has with the classical scaling method based on dimensional analysis, non-dimensionalization, and the Vaschy-Buckingham-Π theorem. Key points of the Lie group theory, and the application of the Lie scaling transformation, are outlined and a comparison is made with two classical scaling models through two examples: unconfined groundwater flow and contaminant transport. The Lie scaling method produces an invariant scaling transformation of the prototype variables, which ensures the dynamics between the model and prototype systems will be preserved. Lie scaling can also be used to determine the conditions under which a complete model is dynamically, kinematically, and geometrically similar to the prototype phenomenon. Similarities between the Lie and classical scaling methods are explained, and the relative strengths and weaknesses of the techniques are discussed.

  5. The design of a turboshaft speed governor using modern control techniques

    NASA Technical Reports Server (NTRS)

    Delosreyes, G.; Gouchoe, D. R.

    1986-01-01

    The objectives of this program were: to verify the model of off schedule compressor variable geometry in the T700 turboshaft engine nonlinear model; to evaluate the use of the pseudo-random binary noise (PRBN) technique for obtaining engine frequency response data; and to design a high performance power turbine speed governor using modern control methods. Reduction of T700 engine test data generated at NASA-Lewis indicated that the off schedule variable geometry effects were accurate as modeled. Analysis also showed that the PRBN technique combined with the maximum likelihood model identification method produced a Bode frequency response that was as accurate as the response obtained from standard sinewave testing methods. The frequency response verified the accuracy of linear models consisting of engine partial derivatives and used for design. A power turbine governor was designed using the Linear Quadratic Regulator (LQR) method of full state feedback control. A Kalman filter observer was used to estimate helicopter main rotor blade velocity. Compared to the baseline T700 power turbine speed governor, the LQR governor reduced droop up to 25 percent for a 490 shaft horsepower transient in 0.1 sec simulating a wind gust, and up to 85 percent for a 700 shaft horsepower transient in 0.5 sec simulating a large collective pitch angle transient.

  6. Advanced grazing-incidence techniques for modern soft-matter materials analysis

    DOE PAGES

    Hexemer, Alexander; Müller-Buschbaum, Peter

    2015-01-01

    The complex nano-morphology of modern soft-matter materials is successfully probed with advanced grazing-incidence techniques. Based on grazing-incidence small- and wide-angle X-ray and neutron scattering (GISAXS, GIWAXS, GISANS and GIWANS), new possibilities arise which are discussed with selected examples. Due to instrumental progress, highly interesting possibilities for local structure analysis in this material class arise from the use of micro- and nanometer-sized X-ray beams in micro- or nanofocused GISAXS and GIWAXS experiments. The feasibility of very short data acquisition times down to milliseconds creates exciting possibilities forin situandin operandoGISAXS and GIWAXS studies. Tuning the energy of GISAXS and GIWAXS in themore » soft X-ray regime and in time-of flight GISANS allows the tailoring of contrast conditions and thereby the probing of more complex morphologies. In addition, recent progress in software packages, useful for data analysis for advanced grazing-incidence techniques, is discussed.« less

  7. Advanced grazing-incidence techniques for modern soft-matter materials analysis

    SciTech Connect

    Hexemer, Alexander; Müller-Buschbaum, Peter

    2015-01-01

    The complex nano-morphology of modern soft-matter materials is successfully probed with advanced grazing-incidence techniques. Based on grazing-incidence small- and wide-angle X-ray and neutron scattering (GISAXS, GIWAXS, GISANS and GIWANS), new possibilities arise which are discussed with selected examples. Due to instrumental progress, highly interesting possibilities for local structure analysis in this material class arise from the use of micro- and nanometer-sized X-ray beams in micro- or nanofocused GISAXS and GIWAXS experiments. The feasibility of very short data acquisition times down to milliseconds creates exciting possibilities forin situandin operandoGISAXS and GIWAXS studies. Tuning the energy of GISAXS and GIWAXS in the soft X-ray regime and in time-of flight GISANS allows the tailoring of contrast conditions and thereby the probing of more complex morphologies. In addition, recent progress in software packages, useful for data analysis for advanced grazing-incidence techniques, is discussed.

  8. Spinal anaesthesia for caesarean section: an ultrasound comparison of two different landmark techniques.

    PubMed

    Srinivasan, K Kallidaikurichi; Deighan, M; Crowley, L; McKeating, K

    2014-08-01

    Spinal anaesthesia performed at levels higher than the L3-4 intervertebral space may result in spinal cord injury. Our aim was to establish a protocol to reduce the chance of spinal anaesthesia performed at or above L2-3. One hundred and ten consenting patients at 32weeks of gestation or greater scheduled for non-emergency caesarean section under spinal anaesthesia were randomly allocated to have needle insertion performed at an intervertebral space determined by one of two landmark techniques. In Group A, if the intercristal line intersected an intervertebral space, this space was selected or if the intercristal line intersected a spinous process the space immediately above was selected. In Group B, if the intercristal line intersected an intervertebral space or a spinous process, the intervertebral space immediately below was chosen. The actual intervertebral space chosen was identified using ultrasound by a blinded investigator. In Group A, an intervertebral space at or above L2-3 was marked in 25 (45.5%) patients compared with 4 (7.3%) in Group B (P <0.001). In 5/55 (9.1%) patients in Group A, the intervertebral space initially chosen was L1-2 whereas this occurred in no patient in Group B. There was no difference between groups in number of needle passes or attempts, onset of block at 5, 10 and 15min or need for rescue analgesia. Our data suggest that when performing spinal anaesthesia in pregnant patients, if the intercristal line intersects an intervertebral space then the space below should be chosen and if the intercristal line intersects a spinous process then the interspace below should be chosen. This will reduce the incidence of spinal anaesthesia performed at or above L2-3. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Detection of the intima and media layer thickness of ultrasound common carotid artery image using efficient active contour segmentation technique.

    PubMed

    Santhiyakumari, N; Rajendran, P; Madheswaran, M; Suresh, S

    2011-11-01

    An active contour segmentation technique for extracting the intima-media layer of the common carotid artery (CCA) ultrasound images employing semiautomatic region of interest identification and speckle reduction techniques is presented in this paper. An attempt has been made to test the ultrasound images of the carotid artery of different subjects with this contour segmentation based on improved dynamic programming method. It is found that the preprocessing of ultrasound images of the CCA with region identification and despeckleing followed by active contour segmentation algorithm can be successfully used in evaluating the intima-media thickness (IMT) of the normal and abnormal subjects. It is also estimated that the segmentation used in this paper results an intermethod error of 0.09 mm and a coefficient of variation of 18.9%, for the despeckled images. The magnitudes of the IMT values have been used to explore the rate of prediction of blockage existing in the cerebrovascular and cardiovascular pathologies and also hypertension and atherosclerosis.

  10. Comparison of tissue heating between manual and hands-free ultrasound techniques.

    PubMed

    Gulick, Dawn T

    2010-02-01

    The objective of this single-factor repeated-measures design was to examine the effectiveness of tissue heating with a hands-free ultrasound (US) technique compared to a hand-held US transducer using the Rich-Mar AutoSound unit. US is a therapeutic modality often used to provide deep tissue heating. Recently, a "hands-free" US unit was introduced by Rich-Mar Incorporated. This unit allows the clinician to choose the mode of US delivery, using either a handheld (manual) transducer or a hands-free device that pulses the US beam through the transducer. However, the Center for Medicare and Medicaid Services has deemed delivery of US via a hands-free unit to be investigational. Forty volunteers over 18 years of age participated. Treatment was provided at a 3-MHz US frequency. Muscle temperature was measured with 26-gauge, 4-cm Physiotemp thermistors placed in the triceps surae muscle. The depth of thermistor placement was at 1 - and 2-cm deep. One calf was treated with a manual transducer (5-cm(2) US head at three times the effective radiating area [ERA]), and one calf was treated with the hands-free transducer (14-cm(2) [ERA]). Both methods used a 1.5 W/cm(2) intensity for 10 minutes. The manual technique used an overlapping circular method at 4 cm/sec, and the hands-free method used a sequential pulsing at 4 cm/sec. Tissue temperatures were recorded at baseline and every 30 seconds. The hands-free technique resulted in a tissue temperature increase from 33.68 to 38.7 degrees C and an increase from 33.45 to 40.1 degrees C using the manual technique at 1-cm depth. The tissue temperature increase at the 2-cm depth was from 34.95 to 35.44 degrees C for the hands-free device and 34.44 to 38.42 degrees C for the manual device. Thus, there was a significant difference between the hands-free and the manual mode of US delivery for the 3-MHz frequency (5.02 degrees C vs. 6.65 degrees C at 1 cm and 1.49 degrees C vs. 3.98 degrees C at 2 cm). In this study, the "hands

  11. A model system and technique to study the effects of ultrasound irradiation on embryonic development.

    PubMed

    Rosenthal, M S; Yip, Y P; Capriotti, C; Yip, J W

    1991-08-01

    To study the effects of ultrasound on development it is important to have a system which provides reliable results. We have designed a system which allows for reproducible irradiations of chick embryos in ovo. The irradiation system includes a heated sonation tank with ultrasound absorbers and a PC/AT computer-based data acquisition system for on-line monitoring of irradiations. The ultrasound detection microprobe and irradiation transducers were calibrated against an NBS traceable balance meter. An acoustic spacer was utilized to provide a more uniform profile of the irradiation beam. At the position of the embryo the ultrasound field geometry was determined. To maintain the chick embryo in its natural physiological state while minimizing ultrasonic reflections and standing-wave generation, two diametrically opposed windows were made in the eggshell along the ultrasound pathway and covered with polyethylene membranes. Using this irradiation system at intensity levels as high as 1.1 W/cm2 (spatial average, temporal average) for 10 min, the temperature rise is minimal.

  12. A novel technique of needle setting for curvilinear endobronchial ultrasound: Improved efficiency with no cost

    PubMed Central

    Meena, Nikhil; Innabi, Ayoub; Alzghoul, Bashar; Bartter, Thaddeus

    2016-01-01

    Background: Standard instructions for biopsy using the convex curvilinear endobronchial ultrasound scope include visualization and adjustment of the sheath housing the biopsy needle before every puncture. In our practice, we pre-set this relationship before inserting the endobronchial ultrasound scope and leave it fixed for every puncture. Objective: We postulated that this approach is more efficient than repeated re-adjustment and aimed to show that it would not increase the frequency of endobronchial ultrasound scope damage. Methods: Retrospective review of every biopsy using the endobronchial ultrasound scope over a 6-year period with documentation of damages and costs. Results: There were 15 scope damages out of 1792 procedures (0.8%). Eight damages were determined to be due to needle damage, one due to patient bite, three due to Williams airway abrasions, and three were camera failures. All damages occurred during the first 5 years of the study. Costs totaled US$138,725, for an average of US$23,120 per year. This rate of damages appears to be similar to or lower than that reported when standard instructions are followed. Conclusion: Pre-setting of the biopsy needle when the endobronchial ultrasound scope is used leads to greater efficiency and no increase in scope damages. PMID:27974969

  13. PREFACE: IX International Conference on Modern Techniques of Plasma Diagnostics and their Application

    NASA Astrophysics Data System (ADS)

    Savjolov, A. S.; Dodulad, E. I.

    2016-01-01

    The IX Conference on ''Modern Techniques of Plasma Diagnosis and their Application'' was held on 5 - 7 November, 2014 at National Research Nuclear University MEPhI (NRNU MEPhI). The goal of the conference was an exchange of information on both high-temperature and low-temperature plasma diagnostics as well as deliberation and analysis of various diagnostic techniques and their applicability in science, industry, ecology, medicine and other fields. The Conference also provided young scientists from scientific centres and universities engaged in plasma diagnostics with an opportunity to attend the lectures given by the leading specialists in this field as well as present their own results and findings. The first workshop titled ''Modern problems of plasma diagnostics and their application for control of chemicals and the environment'' took place at Moscow Engineering and Physics Institute (MEPhI) in June 1998 with the support of the Section on Diagnostics of the Council of Russian Academic of Science on Plasma Physics and since then these forums have been held at MEPhI every two years. In 2008 the workshop was assigned a conference status. More than 150 specialists on plasma diagnostics and students took part in the last conference. They represented leading Russian scientific centres (such as Troitsk Institute of Innovative and Thermonuclear Research, National Research Centre ''Kurchatov Institute'', Russian Federal Nuclear Centre - All-Russian Scientific Research Institute of Experimental Physics and others) and universities from Belarus, Ukraine, Germany, USA, Belgium and Sweden. About 30 reports were made by young researchers, students and post-graduate students. All presentations during the conference were broadcasted online over the internet with viewers in Moscow, Prague, St. Petersburgh and other cities. The Conference was held within the framework of the Centre of Plasma, Laser Research and Technology supported by MEPhI Academic Excellence Project (Russian

  14. PREFACE: 21th International Conference for Students and Young Scientists: Modern Technique and Technologies (MTT'2015)

    NASA Astrophysics Data System (ADS)

    2015-10-01

    Involving young researchers in the scientific process, and allowing them to gain scientific experience, are important issues for scientific development. The International Conference for Students and Young Scientists ''Modern Technique and Technologies'' is one of a number of scientific events, held at National Research Tomsk Polytechnic University aimed at training and forming the scientific elite. During previous years the conference established itself as a serious scientific event at an international level, attracting members which annually number about 400 students and young scientists from Russia and near and far abroad. An important indicator of this scientific event is the large number of scientific areas covered, such as power engineering, heat power engineering, electronic devices for monitoring and diagnostics, instrumentation, materials and technologies of new generations, methods of research and diagnostics of materials, automatic control and system engineering, physical methods science and engineering, design and artistic aspects of engineering, social and humanitarian aspects of engineering. The main issues, which are discussed at the conference by young researchers, are connected with analysis of contemporary problems, application of new techniques and technologies, and consideration of their relationship. Over the years, the conference committee has gained a lot of experience in organizing scientific meetings. There are all the necessary conditions: the staff of organizers includes employees of Tomsk Polytechnic University; the auditoriums are equipped with modern demonstration and office equipment; leading scientists are TPU professors; the status of the Tomsk Polytechnic University as a leading research university in Russia also plays an important role. All this allows collaboration between leading scientists from all around the world, who are annually invited to give lectures at the conference. The editorial board expresses gratitude to the

  15. Incidence of posterior wall penetration during internal jugular vein cannulation: A comparison of two techniques using real-time ultrasound

    PubMed Central

    Srinivasan, Shrikanth; Govil, Deepak; Gupta, Sachin; Patel, Sweta; Jagadeesh, KN; Tomar, Deeksha Singh

    2017-01-01

    Background and Aims: The true incidence of penetration of the posterior wall (through-and-through puncture) of the internal jugular vein (IJV) during cannulation is unknown. This may have implications if there is hematoma formation, penetration and/or inadvertent cannulation of an underlying carotid artery. This study compared the incidence of posterior wall puncture during IJV cannulation using ultrasound guidance versus traditional landmarks-guided technique. Methods: One hundred and seventy adult patients admitted to a gastro-liver Intensive Care Unit who required central venous lines were randomly divided into Group A: IJV cannulation using anatomical landmark-guided technique and Group B: IJV cannulation using real-time ultrasound guidance. In both groups, a second investigator followed the needle path using real-time ultrasound. The incidence of posterior wall puncture, number of attempts for successful cannulation, incidence of inadvertent arterial punctures and occurrence of complications such as hematoma formation and pneumothorax were recorded. Results: Significantly more (37/80, 46%) patients in Group A had posterior wall puncture compared to 19/90 (21%) in Group B. Incidence of arterial puncture was 8/80 (10%) in Group A, 5/90 (5.5%) in Group B. The number of attempts for venous cannulation and hematoma formation was significantly less in Group B. Conclusion: Real-time ultrasound-guided IJV cannulation significantly reduces but does not wholly eliminate the incidence of posterior venous wall penetrations. It also significantly reduces the incidence of inadvertent arterial punctures and number of attempts for successful cannulation. PMID:28405038

  16. Review on Enhanced Heat Transfer Techniques using Modern Technologies for 4S Air Cooled Engines

    NASA Astrophysics Data System (ADS)

    Ramasubramanian, S.; Bupesh Raja, V. K.

    2017-05-01

    Engine performance is a biggest challenge and a vital area of concern when it comes to automobiles. Researchers across the globe have been working decades together meticulously improvising the performance of engine in terms of efficiency. The durability of the engine components mainly depends on the thermal stress it undergoes over the period of operation. Air cooling of engine is the simplest and most desirous technique that has been adopted for ages. In this regard fins or extended surfaces are employed for effective cooling of the cylinder while in operation. The conductive and convective heat transfer rate from the cylinder to the fins and in turn from the fins to surrounding ambience determines the effective performance of the engine. In this paper an attempt is made to review and summarize the various researches that were conducted on the Fins in terms of profile geometry, number of fins, size, thickness factor, material used etc., and to bring about a long term solution with the modern technologies like nano coatings and nano materials.

  17. [A brief history of resuscitation - the influence of previous experience on modern techniques and methods].

    PubMed

    Kucmin, Tomasz; Płowaś-Goral, Małgorzata; Nogalski, Adam

    2015-02-01

    Cardiopulmonary resuscitation (CPR) is relatively novel branch of medical science, however first descriptions of mouth-to-mouth ventilation are to be found in the Bible and literature is full of descriptions of different resuscitation methods - from flagellation and ventilation with bellows through hanging the victims upside down and compressing the chest in order to stimulate ventilation to rectal fumigation with tobacco smoke. The modern history of CPR starts with Kouwenhoven et al. who in 1960 published a paper regarding heart massage through chest compressions. Shortly after that in 1961Peter Safar presented a paradigm promoting opening the airway, performing rescue breaths and chest compressions. First CPR guidelines were published in 1966. Since that time guidelines were modified and improved numerously by two leading world expert organizations ERC (European Resuscitation Council) and AHA (American Heart Association) and published in a new version every 5 years. Currently 2010 guidelines should be obliged. In this paper authors made an attempt to present history of development of resuscitation techniques and methods and assess the influence of previous lifesaving methods on nowadays technologies, equipment and guidelines which allow to help those women and men whose life is in danger due to sudden cardiac arrest. © 2015 MEDPRESS.

  18. Processing of calamine with modern analytical techniques: Processed with Huanglian Decoction () and Sanhuang Decoction ().

    PubMed

    Meng, Xiang-Long; Ma, Jun-Nan; Guo, Xiao-Hui; Liu, Bing-Chen; Cui, Nan-Nan; Li, Kun; Zhang, Shuo-Sheng

    2017-07-28

    To determine the pyrolysis characteristics of calcined and processed calamine, qualitatively and quantitatively compare the contents of related elements, morphology and functional groups of the pyrolysis products dried at different heating temperatures and explore the critical temperature and the optimal drying temperature for the process of calamine with Huanglian Decoction (HLD, ) and San Huang Decoction (SHD, ). Pyrolysis products were prepared by programmable and constantly heating the calcined and processed calamine to or at different heating temperatures. Thermogravimetry (TG) was used to test their pyrolysis characteristics. Fourier transform infrared spectroscopy and scanning electron microscopeenergy dispersive spectrometer were used to determine their morphology, functional groups and element contents. Page model was used to investigate the constant drying kinetics of processed calamine. The adding of HLD or SHD to calcined calamine (CC) can slow its weight loss in drying pyrolysis process. The temperature ranges where HLD and SHD can affect its weight loss were 65-150 °C and 74-180 °C, respectively. The drying temperature was optimized as 90 °C. The drying kinetic for the processed calamine fits Page model shows good linearity. The critical temperature and the optimal drying temperature where HLD and SHD can affect the weight loss rate in the process of calamine were explored using the theories and methods of both biophysical chemistry and processing of Chinese materia medica. This work provides a good example for the study of the process of other Chinese medicines using modern analytical techniques.

  19. Modern Chemistry Techniques Applied to Metal Behavior and Chelation in Medical and Environmental Systems ? Final Report

    SciTech Connect

    Sutton, M; Andresen, B; Burastero, S R; Chiarappa-Zucca, M L; Chinn, S C; Coronado, P R; Gash, A E; Perkins, J; Sawvel, A M; Szechenyi, S C

    2005-02-03

    This report details the research and findings generated over the course of a 3-year research project funded by Lawrence Livermore National Laboratory (LLNL) Laboratory Directed Research and Development (LDRD). Originally tasked with studying beryllium chemistry and chelation for the treatment of Chronic Beryllium Disease and environmental remediation of beryllium-contaminated environments, this work has yielded results in beryllium and uranium solubility and speciation associated with toxicology; specific and effective chelation agents for beryllium, capable of lowering beryllium tissue burden and increasing urinary excretion in mice, and dissolution of beryllium contamination at LLNL Site 300; {sup 9}Be NMR studies previously unstudied at LLNL; secondary ionization mass spec (SIMS) imaging of beryllium in spleen and lung tissue; beryllium interactions with aerogel/GAC material for environmental cleanup. The results show that chelator development using modern chemical techniques such as chemical thermodynamic modeling, was successful in identifying and utilizing tried and tested beryllium chelators for use in medical and environmental scenarios. Additionally, a study of uranium speciation in simulated biological fluids identified uranium species present in urine, gastric juice, pancreatic fluid, airway surface fluid, simulated lung fluid, bile, saliva, plasma, interstitial fluid and intracellular fluid.

  20. World War II, tantalum, and the evolution of modern cranioplasty technique.

    PubMed

    Flanigan, Patrick; Kshettry, Varun R; Benzel, Edward C

    2014-04-01

    Cranioplasty is a unique procedure with a rich history. Since ancient times, a diverse array of materials from coconut shells to gold plates has been used for the repair of cranial defects. More recently, World War II greatly increased the demand for cranioplasty procedures and renewed interest in the search for a suitable synthetic material for cranioprostheses. Experimental evidence revealed that tantalum was biologically inert to acid and oxidative stresses. In fact, the observation that tantalum did not absorb acid resulted in the metal being named after Tantalus, the Greek mythological figure who was condemned to a pool of water in the Underworld that would recede when he tried to take a drink. In clinical use, malleability facilitated a single-stage cosmetic repair of cranial defects. Tantalum became the preferred cranioplasty material for more than 1000 procedures performed during World War II. In fact, its use was rapidly adopted in the civilian population. During World War II and the heyday of tantalum cranioplasty, there was a rapid evolution in prosthesis implantation and fixation techniques significantly shaping how cranioplasties are performed today. Several years after the war, acrylic emerged as the cranioplasty material of choice. It had several clear advantages over its metallic counterparts. Titanium, which was less radiopaque and had a more optimal thermal conductivity profile (less thermally conductive), eventually supplanted tantalum as the most common metallic cranioplasty material. While tantalum cranioplasty was popular for only a decade, it represented a significant breakthrough in synthetic cranioplasty. The experiences of wartime neurosurgeons with tantalum cranioplasty played a pivotal role in the evolution of modern cranioplasty techniques and ultimately led to a heightened understanding of the necessary attributes of an ideal synthetic cranioplasty material. Indeed, the history of tantalum cranioplasty serves as a model for innovative

  1. Measurement of the normalized broadband ultrasound attenuation in trabecular bone by using a bidirectional transverse transmission technique

    NASA Astrophysics Data System (ADS)

    Lee, Kang Il

    2015-01-01

    A new method for measuring the normalized broadband ultrasound attenuation (nBUA) in trabecular bone by using a bidirectional transverse transmission technique was proposed and validated with measurements obtained by using the conventional transverse transmission technique. There was no significant difference between the nBUA measurements obtained for 14 bovine femoral trabecular bone samples by using the bidirectional and the conventional transverse transmission techniques. The nBUA measured by using the two transverse transmission techniques showed strong positive correlations of r = 0.87 to 0.88 with the apparent bone density, consistent with the behavior in human trabecular bone invitro. We expect that the new method can be usefully applied for improved accuracy and precision in clinical measurements.

  2. Technique for iliopsoas ultrasound-guided active electromyography-directed botulinum a toxin injection in cerebral palsy.

    PubMed

    Willenborg, Michael J; Shilt, Jeffrey S; Smith, Beth Paterson; Estrada, Roquel L; Castle, Jason A; Koman, L Andrew

    2002-01-01

    Symptomatic hip flexion deformity secondary to iliopsoas spasticity may interfere with gait, impair sitting balance, or contribute to hip subluxation or dislocation. A nonsurgical, minimally invasive technique to ameliorate iliopsoas spasticity is presented. The technique uses intramuscular injections of botulinum A toxin to provide selective neuromuscular blockade of the iliacus or psoas muscles or both. Because of the anatomic location of the target muscles, this technique uses ultrasound guidance for needle placement. Active electromyographic stimulation is used to verify the needle position adjacent to active myoneural interfaces. The authors' experience to date includes the treatment of 28 patients (53 hips). Use of this technique has resulted in improved hip range of motion. No intraoperative or postoperative adverse events or complications have been observed.

  3. Role of contrast-enhanced ultrasound (CEUS) in the diagnosis of endometrial pathology

    PubMed Central

    POP, CIPRIAN MIHAITA; MIHU, DAN; BADEA, RADU

    2015-01-01

    Ultrasound is the reference imaging procedure used for the exploration of endometrial pathology. As medical procedures improve and the requirements of modern medicine become more demanding, gray-scale ultrasound is insufficient in establishing gynecological diagnosis. Thus, more complex examination techniques are required: Doppler ultrasound, contrast-enhanced ultrasound (CEUS), 3D ultrasound, etc. Contrast-enhanced ultrasound is a special examination technique that gains more and more ground. This allows a detailed real-time evaluation of microcirculation in a certain territory, which is impossible to perform by Doppler ultrasound. The aim of this review is to synthesize current knowledge regarding CEUS applications in endometrial pathology, to detail the technical aspects of endometrial CEUS and the physical properties of the equipment and contrast agents used, as well as to identify the limitations of the method. PMID:26733740

  4. COMPARISON OF ULTRASOUND-GUIDED VS. STANDARD LANDMARK TECHNIQUES FOR TRAINING NOVICE OPERATORS IN PLACING NEEDLES INTO THE LUMBAR SUBARACHNOID SPACE OF CANINE CADAVERS.

    PubMed

    Etienne, Anne-Laure; Delguste, Catherine; Busoni, Valeria

    2016-07-01

    The standard technique for placing a needle into the canine lumbar subarachnoid space is primarily based on palpation of anatomic landmarks and use of probing movements of the needle, however, this technique can be challenging for novice operators. The aim of the current observational, prospective, ex vivo, feasibility study was to compare ultrasound-guided vs. standard anatomic landmark approaches for novices performing needle placement into the lumbar subarachnoid space using dog cadavers. Eight experienced operators validated the canine cadaver model as usable for training landmark and ultrasound-guided needle placement into the lumbar subarachnoid space based on realistic anatomy and tissue consistency. With informed consent, 67 final year veterinary students were prospectively enrolled in the study. Students had no prior experience in needle placement into the lumbar subarachnoid space or use of ultrasound. Each student received a short theoretical training about each technique before the trial and then attempted blind landmark-guided and ultrasound-guided techniques on randomized canine cadavers. After having performed both procedures, the operators completed a self-evaluation questionnaire about their performance and self-confidence. Total success rates for students were 48% and 77% for the landmark- and ultrasound-guided techniques, respectively. Ultrasound guidance significantly increased total success rate when compared to the landmark-guided technique and significantly reduced the number of attempts. With ultrasound guidance self-confidence was improved, without bringing any significant change in duration of the needle placement procedure. Findings indicated that use of ultrasound guidance and cadavers are feasible methods for training novice operators in needle placement into the canine lumbar subarachnoid space. © 2016 American College of Veterinary Radiology.

  5. Ultrasound-guided bilateral superficial cervical plexus block is more effective than landmark technique for reducing pain from thyroidectomy

    PubMed Central

    Senapathi, Tjokorda Gde Agung; Widnyana, I Made Gede; Aribawa, I Gusti Ngurah Mahaalit; Wiryana, Made; Sinardja, I Ketut; Nada, I Ketut Wibawa; Jaya, AA Gde Putra Semara; Putra, I Gede Koko Swadharma

    2017-01-01

    Purpose Thyroidectomy causes postoperative pain and patient discomfort. Bilateral superficial cervical plexus block is a regional anesthesia technique that can provide analgesia during and after surgery. This study aims to compare the effectiveness of ultrasound (US)-guided versus landmark (LM) technique for bilateral superficial cervical plexus block in thyroidectomy. Patients and methods Thirty-six patients undergoing thyroidectomy were divided into two groups randomly (n=18); either US-guided (US group) or LM technique (LM group) for bilateral superficial cervical plexus block. Patient-controlled analgesia was used to control postoperative pain. Intraoperative opioid rescue, postoperative visual analog scale (VAS) score and opioid consumption were measured. Results The number of patients who required intraoperative opioid rescue was significantly lower in the US group (p≤0.05). There was no significant difference in postoperative VAS score at 3 hours (p>0.05), but postoperative VAS score at 6 and 24 hours was significantly lower in the US group (p≤0.05). Twenty-four hour postoperative opioid consumption was significantly lower in the US group (p≤0.05). Conclusion Ultrasound-guided bilateral superficial cervical plexus block is more effective in reducing pain both intra- and postoperatively compared with landmark technique in patients undergoing thyroidectomy. PMID:28761368

  6. Ultrasound-guided bilateral superficial cervical plexus block is more effective than landmark technique for reducing pain from thyroidectomy.

    PubMed

    Senapathi, Tjokorda Gde Agung; Widnyana, I Made Gede; Aribawa, I Gusti Ngurah Mahaalit; Wiryana, Made; Sinardja, I Ketut; Nada, I Ketut Wibawa; Jaya, Aa Gde Putra Semara; Putra, I Gede Koko Swadharma

    2017-01-01

    Thyroidectomy causes postoperative pain and patient discomfort. Bilateral superficial cervical plexus block is a regional anesthesia technique that can provide analgesia during and after surgery. This study aims to compare the effectiveness of ultrasound (US)-guided versus landmark (LM) technique for bilateral superficial cervical plexus block in thyroidectomy. Thirty-six patients undergoing thyroidectomy were divided into two groups randomly (n=18); either US-guided (US group) or LM technique (LM group) for bilateral superficial cervical plexus block. Patient-controlled analgesia was used to control postoperative pain. Intraoperative opioid rescue, postoperative visual analog scale (VAS) score and opioid consumption were measured. The number of patients who required intraoperative opioid rescue was significantly lower in the US group (p≤0.05). There was no significant difference in postoperative VAS score at 3 hours (p>0.05), but postoperative VAS score at 6 and 24 hours was significantly lower in the US group (p≤0.05). Twenty-four hour postoperative opioid consumption was significantly lower in the US group (p≤0.05). Ultrasound-guided bilateral superficial cervical plexus block is more effective in reducing pain both intra- and postoperatively compared with landmark technique in patients undergoing thyroidectomy.

  7. Workflow and intervention times of MR-guided focused ultrasound - Predicting the impact of new techniques.

    PubMed

    Loeve, Arjo J; Al-Issawi, Jumana; Fernandez-Gutiérrez, Fabiola; Langø, Thomas; Strehlow, Jan; Haase, Sabrina; Matzko, Matthias; Napoli, Alessandro; Melzer, Andreas; Dankelman, Jenny

    2016-04-01

    Magnetic resonance guided focused ultrasound surgery (MRgFUS) has become an attractive, non-invasive treatment for benign and malignant tumours, and offers specific benefits for poorly accessible locations in the liver. However, the presence of the ribcage and the occurrence of liver motion due to respiration limit the applicability MRgFUS. Several techniques are being developed to address these issues or to decrease treatment times in other ways. However, the potential benefit of such improvements has not been quantified. In this research, the detailed workflow of current MRgFUS procedures was determined qualitatively and quantitatively by using observation studies on uterine MRgFUS interventions, and the bottlenecks in MRgFUS were identified. A validated simulation model based on discrete events simulation was developed to quantitatively predict the effect of new technological developments on the intervention duration of MRgFUS on the liver. During the observation studies, the duration and occurrence frequencies of all actions and decisions in the MRgFUS workflow were registered, as were the occurrence frequencies of motion detections and intervention halts. The observation results show that current MRgFUS uterine interventions take on average 213min. Organ motion was detected on average 2.9 times per intervention, of which on average 1.0 actually caused a need for rework. Nevertheless, these motion occurrences and the actions required to continue after their detection consumed on average 11% and up to 29% of the total intervention duration. The simulation results suggest that, depending on the motion occurrence frequency, the addition of new technology to automate currently manual MRgFUS tasks and motion compensation could potentially reduce the intervention durations by 98.4% (from 256h 5min to 4h 4min) in the case of 90% motion occurrence, and with 24% (from 5h 19min to 4h 2min) in the case of no motion. In conclusion, new tools were developed to predict how

  8. "Reinventing" Techniques for the Estimation of the Area of Irregular Plane Figures: From the Eighteenth Century to the Modern Classroom

    ERIC Educational Resources Information Center

    Papadopoulos, Ioannis

    2010-01-01

    The issue of the area of irregular shapes is absent from the modern mathematical textbooks in elementary education in Greece. However, there exists a collection of books written for educational purposes by famous Greek scholars dating from the eighteenth century, which propose certain techniques concerning the estimation of the area of such…

  9. Hypothesis Testing, "p" Values, Confidence Intervals, Measures of Effect Size, and Bayesian Methods in Light of Modern Robust Techniques

    ERIC Educational Resources Information Center

    Wilcox, Rand R.; Serang, Sarfaraz

    2017-01-01

    The article provides perspectives on p values, null hypothesis testing, and alternative techniques in light of modern robust statistical methods. Null hypothesis testing and "p" values can provide useful information provided they are interpreted in a sound manner, which includes taking into account insights and advances that have…

  10. Synthesis of titanium dioxide by ultrasound assisted sol-gel technique: effect of calcination and sonication time.

    PubMed

    Pinjari, D V; Prasad, Krishnamurthy; Gogate, P R; Mhaske, S T; Pandit, A B

    2015-03-01

    Nanostructured titanium dioxide has been synthesized using both conventional and ultrasound assisted sol-gel technique with an objective of understanding the role of cavitational effects in the synthesis process. The experiments were conducted at a constant calcination temperature of 750 °C and the calcination time was varied from 30 min to 3 h to study the effect of calcination time on the properties of the synthesized TiO₂. The TiO₂ specimens were characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The influence of the sonication time on the phase transformation process from anatase to rutile and also on the crystallite size and percentage crystallinity of the synthesized TiO₂ has also been investigated. It was observed that 100% phase transformation occurred after 3 h of calcination for the ultrasound assisted sol-gel synthesized TiO₂. The study on the phase transformation via variation of sonication time yielded interesting results. It was observed that as the sonication time increased, an initial increase in the rutile content is obtained and beyond optimum sonication time, the rutile content decreased. In general, the ultrasound assisted process results in synthesis of TiO₂ material with higher rutile content as compared to the conventional sol-gel process.

  11. Ultrasound-guided spinal anaesthesia in obstetrics: is there an advantage over the landmark technique in patients with easily palpable spines?

    PubMed

    Ansari, T; Yousef, A; El Gamassy, A; Fayez, M

    2014-08-01

    Data are scarce on the advantage of ultrasound-guided spinal anaesthesia in patients with easily identifiable bony landmarks. In this study, we compared the use of ultrasound to the landmark method in patients with no anticipated technical difficulty, presenting for caesarean delivery under spinal anaesthesia. A total of 150 pregnant women were recruited in this randomized, controlled study. Ultrasound examination and spinal anaesthesia were performed by three anaesthetists with experience in ultrasound-guided neuraxial block. Patients were randomized to either the Ultrasound Group (n=75) or the Landmark Group (n=75). In both groups the level of L3-4 or L4-5 was identified by ultrasound (transverse and longitudinal approach) or palpation. The primary outcome was the procedure time, measured from the time of skin puncture by the introducer to the time of viewing cerebrospinal fluid at the hub of the spinal needle. Secondary outcomes were the number of skin punctures, number of passes, and incidence of successful spinal blockade. The average procedure time, number of skin punctures and needle passes, were similar in both groups. The number of patients with successful spinal anaesthesia after one puncture was not statistically different between the groups. The present results indicate that when performed by anaesthetists experienced in both ultrasound and landmark techniques, the use of ultrasound does not appear to increase the success rate of spinal anaesthesia, or reduce the procedure time or number of attempts in obstetric patients with easily palpable spines. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Technical communication: new teaching model for practicing ultrasound-guided regional anesthesia techniques: no perishable food products!

    PubMed

    Liu, Yang; Glass, Nancy L; Power, Robert W

    2010-04-01

    There is a pronounced learning curve for the technique of ultrasound-guided regional anesthesia. Practicing with a simulator model has been shown to speed the acquisition of these skills for various ultrasound-guided procedures. However, commercial models for ultrasound-guided regional anesthesia may be too costly or not readily available. Models using turkey breasts or tofu blocks have the disadvantage of containing perishable food products that can be a source for infection. We describe an alternative inexpensive model that is made from nonperishable components readily available in the operating room. The materials required include 1 clean used 500-mL bag of IV fluids, a bottle of Premisorb (TYCO Healthcare Group, Mansfield, MA), and a piece of foam material approximately 0.3 cm in diameter and 5 cm in length trimmed from operating room foam pads. After filling the IV bag with tap water and inserting the foam into the IV bag from the outlet port of the IV bag, one-third of a bottle of Premisorb (approximately 15 g) is poured into the IV bag. The outlet port of the bag is then sealed by taping the rubber stopper that originally came with the bag. Premisorb, a solidifying agent frequently used to absorb irrigating fluids or blood in operating room suction canisters, produces a gel-like material in the IV bag. The foam inserted into the bag creates a relatively hyperechoic target. This gel-like substance in the bag will seal the holes created after multiple practice needle insertions, resulting in minimal leakage. The semitransparent nature of the gel allows the trainee to visualize the target directly and on the ultrasound screen. The model we describe is inexpensive and easy to make from materials readily available in the operating room with the advantages of being nonperishable, easy to carry, and reusable.

  13. 2013 European Thyroid Association Guidelines for Cervical Ultrasound Scan and Ultrasound-Guided Techniques in the Postoperative Management of Patients with Thyroid Cancer

    PubMed Central

    Leenhardt, L.; Erdogan, M.F.; Hegedus, L.; Mandel, S.J.; Paschke, R.; Rago, T.; Russ, G.

    2013-01-01

    Cervical ultrasound scanning (US) is considered a key examination, by all major thyroid and endocrine specialist societies for the postoperative follow-up of thyroid cancer patients to assess the risk of recurrence. Neck US imaging is readily available, non-invasive, relatively easy to perform, cost-effective, and can guide diagnostic and therapeutic procedures with low complication rates. Its main shortcoming is its operator-dependency. Because of the pivotal role of US in the care of thyroid cancer patients, the European Thyroid Association convened a panel of international experts to review technical aspects, indications, results, and limitations of cervical US in the initial staging and follow-up of thyroid cancer patients. The main aim is to establish guidelines for both a cervical US scanning protocol and US-guided diagnostic and therapeutic procedures in patients with thyroid cancer. This report presents (1) standardization of the US scanning procedure, techniques of US-guided fine-needle aspiration, and reporting of findings; (2) definition of criteria for classification of malignancy risk based on cervical US imaging characteristics of neck masses and lymph nodes; (3) indications for US-guided fine-needle aspiration and for biological in situ assessments; (4) proposal of an algorithm for the follow-up of thyroid cancer patients based on risk stratification following histopathological and cervical US findings, and (5) discussion of the potential use of US-guided localization and ablation techniques for locoregional thyroid metastases. PMID:24847448

  14. Basic technique in endoscopic ultrasound-guided fine needle aspiration for solid lesions: What needle is the best?

    PubMed Central

    Lachter, Jesse

    2014-01-01

    Basic technique for endoscopic ultrasound (EUS) of solid lesions has developed during 30 years of EUS, as endoscopes and accessory equipment, particularly needles, have been developed. Systematic high-quality examinations require understanding and planning. Needles used for EUS-guided fine needle aspiration (FNA) have gone through many improvements; some 18 characteristics of any needle are presented and these come under consideration whenever choosing the best needle for each procedure. The bright future of EUS and FNA for solid lesions currently still leaves much room for continued developments. PMID:24949410

  15. Diuretic Agent and Normal Saline Infusion Technique for Ultrasound-Guided Percutaneous Nephrostomies in Nondilated Pelvicaliceal Systems

    SciTech Connect

    Yagci, Cemil Ustuner, Evren Atman, Ebru Dusunceli; Baltaci, Sumer; Uzun, Caglar Akyar, Serdar

    2013-04-15

    Percutaneous nephrostomy (PCN) in a nondilated pelvicaliceal system is technically challenging. We describe an effective method to achieve transient dilatation of the pelvicaliceal system via induction of diuresis using infusion of a diuretic agent in normal saline, therefore allowing easier access to the pelvicaliceal system. Under real-time ultrasound guidance, the technique had been tested in 22 nephrostomies with nondilated system (a total of 20 patients with 2 patients having bilateral nephrostomies) during a 5-year period. Patients were given 40 mg of furosemide in 250 ml of normal saline solution intravenously by rapid infusion. As soon as maximum calyceal dilatation of more than 5 mm was observed, which is usually 15 min later after the end of rapid infusion, patients were positioned obliquely, and PCN procedure under ultrasound guidance was performed. The procedure was successful in 19 of the nephrostomies in 17 patients with a success rate of 86.36 % per procedure and 85 % per patient in nondilated pelvicaliceal systems. No major nephrostomy-, drug-, or technique-related complications were encountered. The technique failed to work in three patients due to the presence of double J catheters and preexisting calyceal perforation which avoided transient dilation of the pelvicaliceal system with diuresis. Diuretic infusion in saline is a feasible and effective method for PCN in nondilated pelvicaliceal systems.

  16. In vitro comparison of a novel facilitated ultrasound targeting technology vs standard technique for percutaneous renal biopsy.

    PubMed

    Menhadji, Ashleigh; Nguyen, Vien; Cho, Jane; Chu, Ringo; Osann, Kathyrn; Bucur, Philip; Patel, Puja; Lusch, Achim; McDougall, Elspeth; Landman, Jaime

    2013-09-01

    To improve the understanding of the epidemiology of renal cortical neoplasms through pretreatment biopsy, we evaluated a facilitated ultrasound targeting (FUT) technology. The technology allows a needle to be passed through the transducer probe and guided along a virtual dotted line on the monitor. We compared the FUT with standard percutaneous biopsy (PB) technique. Forty-eight participants with various levels of training were recruited. Participants performed ultrasound-guided biopsies on phantom models using FUT and the standard biopsy technique in a randomized sequence. The phantom models consisted of pimento olives embedded in an opaque mold of Metamucil and Knox gelatin. Patients were given up to 10 attempts to achieve 3 complete specimens from the olives. Patients rated each biopsy technique. Results were stratified by level of experience. The mean time to obtain 3 complete biopsy specimens was significantly faster for FUT compared with the standard technique (140 seconds vs 246 seconds, P = .0001). The mean number of attempts needed to obtain 3 specimens was significantly less with FUT compared with the standard technique (4.3 vs 5.6 attempts, P = .0007). Patients reported that FUT was significantly easier to use compared with the standard technique (P = .0005). No significant order effect was observed. In this in vitro comparison, FUT increased the efficiency and efficacy of PB for users of all experience levels. FUT may allow urologists with limited PB experience to perform the procedure reliably and easily. Clinical evaluation of this technology is actively in progress. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Ultrasound-guided percutaneous cholecystostomy in acute cholecystitis: case vignette and review of the technique.

    PubMed

    Blanco, Pablo A; Do Pico, Juan J

    2015-12-01

    Acute cholecystitis is a frequent condition. Although cholecystectomy is the indicated treatment of this entity, it cannot be performed in some high-risk surgery patients, such as critically ill or those with multiple comorbidities. In these non-uncommon scenarios, percutaneous cholecystostomy is the recommended alternative treatment, which allows immediate decompression and drainage of the acutely inflamed gallbladder and thus reducing the patient's symptoms and the systemic inflammatory response. Ultrasound is the imaging method of choice to guide the percutaneous cholecystostomy procedure due to its real-time guidance, lack of ionizing radiation and portability, avoiding the need to transfer unhealthy patients to the radiology department. We will review the ultrasound-guided percutaneous cholecystostomy procedure, of special interest for radiologists, surgeons, and also intensive care and emergency physicians.

  18. Dual-/tri-apodization techniques for high frequency ultrasound imaging: a simulation study.

    PubMed

    Sung, Jin Ho; Jeong, Jong Seob

    2014-10-11

    In the ultrasound B-mode (Brightness-mode) imaging, high side-lobe level reduces contrast to noise ratio (CNR). A linear apodization scheme by using the window function can suppress the side-lobe level while the main-lobe width is increased resulting in degraded lateral resolution. In order to reduce the side-lobe level without sacrificing the main-lobe width, a non-linear apodization method has been suggested. In this paper, we computationally evaluated the performance of the non-linear apodization method such as dual-/tri-apodization focusing on the high frequency ultrasound image. The rectangular, Dolph-Chebyshev, and Kaiser window functions were employed to implement dual-/tri-apodization algorithms. The point and cyst target simulations were conducted by using a dedicated ultrasound simulation tool called Field-II. The center frequency of the simulated linear array transducer was 40 MHz and the total number of elements was 128. The performance of dual-/tri-apodization was compared with that of the rectangular window function focusing on the side-lobe level and the main-lobe widths (at -6 dB and -35 dB). In the point target simulation, the main-lobe widths of the dual-/tri-apodization were very similar to that of the rectangular window, and the side-lobe levels of the dual-/tri-apodization were more suppressed by 9~10 dB. In the cyst target simulation, CNR values of the dual-/tri-apodization were improved by 41% and 51%, respectively. The performance of the non-linear apodization was numerically investigated. In comparison with the rectangular window function, the non-linear apodization method such as dual- and tri-apodization had low side-lobe level without sacrificing the main-lobe width. Thus, it can be a potential way to increase CNR maintaining the main-lobe width in the high frequency ultrasound imaging.

  19. Modelling of ultrasound tomography technique for Glass Fibre Reinforced Epoxy (GFRE) composites liquid transportation pipeline

    NASA Astrophysics Data System (ADS)

    Siow, L. T.; Rahiman, M. H. F.; Majid, M. S. Abdul; Rahim, R. A.; Zakaria, Z.; Thomas W. K., T.; Ang, Vernoon

    2017-03-01

    The purpose of this paper is to model the ultrasonic tomography on the E-glass fibre reinforced epoxy composite pipe for process monitoring and control. Finite element software and mathematical estimation were applied to model and study the ultrasound wave propagation, especially the reflection and transmission coefficient. While there is a significant result achieved between mathematical estimation and finite element analysis with maximum percentage distinctly in 2.33.

  20. A harmonic cancellation technique for an ultrasound transducer excited by a switched-mode power converter.

    PubMed

    Tang, Sai Chun; Clement, Gregory T

    2008-02-01

    The aim of this study is to evaluate the feasibility of using harmonic cancellation for a therapeutic ultrasound transducer excited by a switched-mode power converter without an additional output filter. A switching waveform without the third harmonic was created by cascading two switched-mode power inverter modules at which their output waveforms were pi/3 phase shifted from each other. A PSPICE simulation model for the power converter output stage was developed. The simulated results were in good agreement with the measurement. The waveform and harmonic contents of the acoustic pressure generated by a 1-MHz, self-focused piezoelectric transducer with and without harmonic cancellation have been evaluated. Measured results indicated that the acoustic third harmonicto- fundamental ratio at the focus was small (-48 dB) with harmonic cancellation, compared to that without harmonic cancellation (-20 dB). The measured acoustic levels of the fifth harmonic for both cases with and without harmonic cancellation also were small (-46 dB) compared to the fundamental. This study shows that it is viable to drive a piezoelectric ultrasound transducer using a switched-mode power converter without the requirement of an additional output filter in many high-intensity focused ultrasound (HIFU) applications.

  1. A novel ultrasound based technique for classifying gas bubble sizes in liquids

    NASA Astrophysics Data System (ADS)

    Hussein, Walid; Salman Khan, Muhammad; Zamorano, Juan; Espic, Felipe; Becerra Yoma, Nestor

    2014-12-01

    Characterizing gas bubbles in liquids is crucial to many biomedical, environmental and industrial applications. In this paper a novel method is proposed for the classification of bubble sizes using ultrasound analysis, which is widely acknowledged for being non-invasive, non-contact and inexpensive. This classification is based on 2D templates, i.e. the average spectrum of events representing the trace of bubbles when they cross an ultrasound field. The 2D patterns are obtained by capturing ultrasound signals reflected by bubbles. Frequency-domain based features are analyzed that provide discrimination between bubble sizes. These features are then fed to an artificial neural network, which is designed and trained to classify bubble sizes. The benefits of the proposed method are that it facilitates the processing of multiple bubbles simultaneously, the issues concerning masking interference among bubbles are potentially reduced and using a single sinusoidal component makes the transmitter-receiver electronics relatively simpler. Results from three bubble sizes indicate that the proposed scheme can achieve an accuracy in their classification that is as high as 99%.

  2. Harmonic motion imaging for focused ultrasound (HMIFU): a fully integrated technique for sonication and monitoring of thermal ablation in tissues.

    PubMed

    Maleke, C; Konofagou, E E

    2008-03-21

    FUS (focused ultrasound), or HIFU (high-intensity-focused ultrasound) therapy, a minimally or non-invasive procedure that uses ultrasound to generate thermal necrosis, has been proven successful in several clinical applications. This paper discusses a method for monitoring thermal treatment at different sonication durations (10 s, 20 s and 30 s) using the amplitude-modulated (AM) harmonic motion imaging for focused ultrasound (HMIFU) technique in bovine liver samples in vitro. The feasibility of HMI for characterizing mechanical tissue properties has previously been demonstrated. Here, a confocal transducer, combining a 4.68 MHz therapy (FUS) and a 7.5 MHz diagnostic (pulse-echo) transducer, was used. The therapy transducer was driven by a low-frequency AM continuous signal at 25 Hz, producing a stable harmonic radiation force oscillating at the modulation frequency. A pulser/receiver was used to drive the pulse-echo transducer at a pulse repetition frequency (PRF) of 5.4 kHz. Radio-frequency (RF) signals were acquired using a standard pulse-echo technique. The temperature near the ablation region was simultaneously monitored. Both RF signals and temperature measurements were obtained before, during and after sonication. The resulting axial tissue displacement was estimated using one-dimensional cross correlation. When temperature at the focal zone was above 48 degrees C during heating, the coagulation necrosis occurred and tissue damage was irreversible. The HMI displacement profiles in relation to the temperature and sonication durations were analyzed. At the beginning of heating, the temperature at the focus increased sharply, while the tissue stiffness decreased resulting in higher HMI displacements. This was confirmed by an increase of 0.8 microm degrees C(-1)(r=0.93, p<.005). After sustained heating, the tissue became irreversibly stiffer, followed by an associated decrease in the HMI displacement (-0.79 microm degrees C(-1), r=-0.92, p<0.001). Repeated

  3. Abdominal ultrasound (image)

    MedlinePlus

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

  4. A novel technique for ultrasound-guided central venous catheterization under short-axis out-of-plane approach: "stepwise flashing with triangulation".

    PubMed

    Horiuchi, Toshinori; Okuda, Chie; Kurita, Naoko; Yamaguchi, Ayako; Kitagawa, Kazuhiko; Takeda, Masafumi; Sha, Keiichi; Nagahata, Toshihiro

    2017-06-20

    In ultrasound-guided central venous catheterization, there is no standard technique either for the needle tip visualization or for the adequate needle angle and entry to the skin with short-axis view under out-of-plane technique. In the present study, we propose a novel technique named "stepwise flashing with triangulation", and the efficacy of this technique is assessed. Before and after a didactic session in which the technique was explained, 12 novice residents were asked to position the needle tip on or into the imitation vessels and to avoid deeper penetration by using an agar tissue phantom with ultrasound guidance. "Stepwise flashing" technique was for stepwise visualization of the needle tip, and "triangulation" technique was for adequate needle angle and entry to the skin. After the session, the success rate was increased and a deeper penetration rate was decreased. This technique will help us to facilitate vascular access and to avoid complications in clinical settings.

  5. Flight control design using a blend of modern nonlinear adaptive and robust techniques

    NASA Astrophysics Data System (ADS)

    Yang, Xiaolong

    In this dissertation, the modern control techniques of feedback linearization, mu synthesis, and neural network based adaptation are used to design novel control laws for two specific applications: F/A-18 flight control and reusable launch vehicle (an X-33 derivative) entry guidance. For both applications, the performance of the controllers is assessed. As a part of a NASA Dryden program to develop and flight test experimental controllers for an F/A-18 aircraft, a novel method of combining mu synthesis and feedback linearization is developed to design longitudinal and lateral-directional controllers. First of all, the open-loop and closed-loop dynamics of F/A-18 are investigated. The production F/A-18 controller as well as the control distribution mechanism are studied. The open-loop and closed-loop handling qualities of the F/A-18 are evaluated using low order transfer functions. Based on this information, a blend of robust mu synthesis and feedback linearization is used to design controllers for a low dynamic pressure envelope of flight conditions. For both the longitudinal and the lateral-directional axes, a robust linear controller is designed for a trim point in the center of the envelope. Then by including terms to cancel kinematic nonlinearities and variations in the aerodynamic forces and moments over the flight envelope, a complete nonlinear controller is developed. In addition, to compensate for the model uncertainty, linearization error and variations between operating points, neural network based adaptation is added to the designed longitudinal controller. The nonlinear simulations, robustness and handling qualities analysis indicate that the performance is similar to or better than that for the production F/A-18 controllers. When the dynamic pressure is very low, the performance of both the experimental and the production flight controllers is degraded, but Level I handling qualities are still achieved. A new generation of Reusable Launch Vehicles

  6. Ultrasound-guided ilioinguinal and iliohypogastric nerve block, a comparison with the conventional technique: An observational study

    PubMed Central

    Khedkar, Sunita Milind; Bhalerao, Pradnya Milind; Yemul-Golhar, Shweta Rahul; Kelkar, Kalpana Vinod

    2015-01-01

    Background: The conventional technique of ilioinguinal and iliohypogastric nerve block may be associated with drug toxicity, block failure and needs large drug volume. The ultrasound-guided (USG) nerve block enables accurate needle positioning that may reduce the chances of drug toxicity, drug dose and block failure. Aim: In this study, we compared the onset and duration of the motor and sensory nerve block, the drug volume required and time to rescue analgesic between USG and conventional technique. Settings and Design: Sixty male patients aged between 18 and 60 years, belonging to American society of Anesthesiology I-II, scheduled for inguinal hernia repair were enrolled in this prospective study and were randomly allocated into two groups of thirty each by computerized method. Materials and Methods: Group A patients received hernia block by conventional method using 0.75% ropivacaine 15 ml, and Group B patients were given the block guided by ultrasound using 0.75% ropivacaine, till the nerves were surrounded on all sides by the drug. Statistical Analysis: The data were analyzed using two independent sample t-tests for demographic and hemodynamic parameters. Nonparametric test (Mann-Whitney U-test) was used to find the significance between visual analog scale. Results: There was significantly early onset of sensory block in Group B 14.03 ± 2.82 min as compared to Group A 15.57 ± 1.52 min (P = 0.047). The onset of motor block was also earlier in Group B 19.40 ± 2.85 min as compared to Group A 20.67 ± 1.90 min. The time to rescue analgesia was more in Group B 7.22 ± 0.97 h as compared to Group A 6.80 ± 0.70 h (P = 0.062). The volume of drug required was less with ultrasound guided block. Conclusions: Ultrasound-guided hernia block thus has the advantage of early onset, less dose requirement and increase in time to rescue analgesia. PMID:26240549

  7. Computer aided prognosis for cell death categorization and prediction in vivo using quantitative ultrasound and machine learning techniques.

    PubMed

    Gangeh, M J; Hashim, A; Giles, A; Sannachi, L; Czarnota, G J

    2016-12-01

    At present, a one-size-fits-all approach is typically used for cancer therapy in patients. This is mainly because there is no current imaging-based clinical standard for the early assessment and monitoring of cancer treatment response. Here, the authors have developed, for the first time, a complete computer-aided-prognosis (CAP) system based on multiparametric quantitative ultrasound (QUS) spectroscopy methods in association with texture descriptors and advanced machine learning techniques. This system was used to noninvasively categorize and predict cell death levels in fibrosarcoma mouse tumors treated using ultrasound-stimulated microbubbles as novel endothelial-cell radiosensitizers. Sarcoma xenograft tumor-bearing mice were treated using ultrasound-stimulated microbubbles, alone or in combination with x-ray radiation therapy, as a new antivascular treatment. Therapy effects were assessed at 2-3, 24, and 72 h after treatment using a high-frequency ultrasound. Two-dimensional spectral parametric maps were generated using the power spectra of the raw radiofrequency echo signal. Subsequently, the distances between "pretreatment" and "post-treatment" scans were computed as an indication of treatment efficacy, using a kernel-based metric on textural features extracted from 2D parametric maps. A supervised learning paradigm was used to either categorize cell death levels as low, medium, or high using a classifier, or to "continuously" predict the levels of cell death using a regressor. The developed CAP system performed at a high level for the classification of cell death levels. The area under curve of the receiver operating characteristic was 0.87 for the classification of cell death levels to both low/medium and medium/high levels. Moreover, the prediction of cell death levels using the proposed CAP system achieved a good correlation (r = 0.68,  p < 0.001) with histological cell death levels as the ground truth. A statistical test of significance between

  8. Comparison of time-frequency distribution techniques for analysis of simulated Doppler ultrasound signals of the femoral artery.

    PubMed

    Guo, Z; Durand, L G; Lee, H C

    1994-04-01

    The time-frequency distribution of the Doppler ultrasound blood flow signal is normally computed by using the short-time Fourier transform or autoregressive modeling. These two techniques require stationarity of the signal during a finite interval. This requirement imposes some limitations on the distribution estimate. In the present study, three new techniques for nonstationary signal analysis (the Choi-Williams distribution, a reduced interference distribution, and the Bessel distribution) were tested to determine their advantages and limitations for analysis of the Doppler blood flow signal of the femoral artery. For the purpose of comparison, a model stimulating the quadrature Doppler signal was developed, and the parameters of each technique were optimized based on the theoretical distribution. Distributions computed using these new techniques were assessed and compared with those computed using the short-time Fourier transform and autoregressive modeling. Three indexes, the correlation coefficient, the integrated squared error, and the normalized root-mean-squared error of the mean frequency waveform, were used to evaluate the performance of each technique. The results showed that the Bessel distribution performed the best, but the Choi-Williams distribution and autoregressive modeling are also techniques which can generate good time-frequency distributions of Doppler signals.

  9. Ultrasound-guided breast interventions: accuracy of biopsy techniques and applications in patient management.

    PubMed

    Shulman, Suzanne G; March, David E

    2006-08-01

    Ultrasound (US) provides a versatile approach for guiding biopsies and other breast interventions. The wide availability, real-time capability, technical improvements, and increasing user experience have greatly expanded the role of US-guided interventions in the diagnosis and management of breast disease. This article reviews the accuracy of US-guided fine-needle aspiration biopsy, automated core biopsy, and vacuum-assisted biopsy. Some of the more specialized procedures that reflect the growing role of US-guided interventions in patient management will also be discussed.

  10. Magnetic Resonance Imaging-Ultrasound Fusion-Guided Prostate Biopsy: Review of Technology, Techniques, and Outcomes.

    PubMed

    Kongnyuy, Michael; George, Arvin K; Rastinehad, Ardeshir R; Pinto, Peter A

    2016-04-01

    Transrectal ultrasound (TRUS)-guided (12-14 core) systematic biopsy of the prostate is the recommended standard for patients with suspicion of prostate cancer (PCa). Advances in imaging have led to the application of magnetic resonance imaging (MRI) for the detection of PCa with subsequent development of software-based co-registration allowing for the integration of MRI with real-time TRUS during prostate biopsy. A number of fusion-guided methods and platforms are now commercially available with common elements in image and analysis and planning. Implementation of fusion-guided prostate biopsy has now been proven to improve the detection of clinically significant PCa in appropriately selected patients.

  11. Multimodal in vivo imaging of oral cancer using fluorescence lifetime, photoacoustic and ultrasound techniques

    PubMed Central

    Fatakdawala, Hussain; Poti, Shannon; Zhou, Feifei; Sun, Yang; Bec, Julien; Liu, Jing; Yankelevich, Diego R.; Tinling, Steven P.; Gandour-Edwards, Regina F.; Farwell, D. Gregory; Marcu, Laura

    2013-01-01

    This work reports a multimodal system for label-free tissue diagnosis combining fluorescence lifetime imaging (FLIm), ultrasound backscatter microscopy (UBM), and photoacoustic imaging (PAI). This system provides complementary biochemical, structural and functional features allowing for enhanced in vivo detection of oral carcinoma. Results from a hamster oral carcinoma model (normal, precancer and carcinoma) are presented demonstrating the ability of FLIm to delineate biochemical composition at the tissue surface, UBM and related radiofrequency parameters to identify disruptions in the tissue microarchitecture and PAI to map optical absorption associated with specific tissue morphology and physiology. PMID:24049693

  12. A review of post-modern management techniques as currently applied to Turkish forestry.

    PubMed

    Dölarslan, Emre Sahin

    2009-01-01

    This paper reviews the effects of six post-modern management concepts as applied to Turkish forestry. Up to now, Turkish forestry has been constrained, both in terms of its operations and internal organization, by a highly bureaucratic system. The application of new thinking in forestry management, however, has recently resulted in new organizational and production concepts that promise to address problems specific to this Turkish industry and bring about positive changes. This paper will elucidate these specific issues and demonstrate how post-modern management thinking is influencing the administration and operational capacity of Turkish forestry within its current structure.

  13. Safety of early ambulation in patients undergoing ultrasound-guided femoral low angle arterial access technique (FLAT).

    PubMed

    Shukla, P A; Kolber, M K; Kumar, A; Patel, R I

    2017-06-01

    To evaluate the safety of early ambulation in patients undergoing transfemoral arterial interventions via ultrasound-guided femoral low angle arterial access technique (FLAT). A total of 58 patients undergoing 72 transfemoral arterial procedures that underwent an attempt at FLAT for femoral artery cannulation at our institution from November 2014 to July 2015 were retrospectively identified. Technical success was defined as obtaining less than a 35-degree angle of entry through the anterior wall of the common femoral artery. Patients for which a low angle was achieved were ambulated after 2hours after hemostasis was achieved with manual compression. All patients received out-patient clinic follow-up which included ultrasound examination of the femoral artery. Chart review provided demographic data, pertinent past medical history, procedural information (type of procedure, size of femoral access sheath, time to ambulation), complications related to arterial access and follow up. Twelve patients were excluded from the study due to inability to analyze ultrasound images. A low angle was achieved in 37 patients (17 men, 20 women; mean age: 58.5 years±13.1 [SD]) undergoing 45 procedures who met inclusion criteria for the study, yielding technical success rate of 75%. There was a moderate positive correlation between the access angle and depth of the common femoral artery at the site of puncture (r=0.45; P<0.01). All patients were followed up within 2 weeks of the initial procedure in the outpatient clinic. No arterial access-related complications occurred. Femoral artery cannulation using FLAT followed by manual compression and ambulation after 2 hours appears to be a safe approach. Copyright © 2016 Éditions françaises de radiologie. Published by Elsevier Masson SAS. All rights reserved.

  14. A new technique for intraluminal hollow organ imaging: three-dimensional ultrasound.

    PubMed

    Cavaye, D M; Tabbara, M R; Kopchok, G E; Laas, T E; Cormier, F; White, R A

    1991-10-01

    Intraluminal ultrasound (ILUS) is a new catheter-based system which produces two-dimensional (2D), cross-sectional images of tubular structures. The principle of image acquisition using 5.0 Fr (30 MHz) and 8.0 Fr (20 MHz) ILUS catheters containing ultrasound transducers at the tip, is equally applicable to all tubular or hollow organs. This article illustrates the feasibility of intraluminal imaging of hollow organ structures, and describes computerized three-dimensional (3D) reconstruction of the 2D images, using a PC-based image analysis system. A set (n = 90) of longitudinally aligned, consecutive 2D images was sampled from various organs (canine bladder, urethra, jejunum, esophagus, and trachea) and computer processed to produce 3D images. By adjusting image density threshold and viewing angle, the lumen and wall morphology can be examined in any projection. Possible applications include diagnosis of lumen encroaching pathology, guidance of intraluminal instruments, and assessment of the effects of endoluminal interventions.

  15. Ultrasound-assisted emulsification of cosmetic samples prior to elemental analysis by different atomic spectrometric techniques.

    PubMed

    Lavilla, I; Cabaleiro, N; Costas, M; de la Calle, I; Bendicho, C

    2009-11-15

    In this work, ultrasound-assisted emulsification with a probe system is proposed as a rapid and simple sample treatment for atomic spectrometric determinations (Electrothermal Atomic Absorption Spectrometry, Inductively Coupled Plasma Optical Emission Spectrometry, Flame Atomic Absorption Spectrometry and Cold Vapour Atomic Absorption Spectrometry) of trace elements (As, Cd, Cr, Cu, Hg, Mg, Mn, Ni, Sr and Zn) in cosmetic samples such as shampoos, gel (hair gel), crèmes (body milk, hair conditioner) and oil (body oil). The type of dispersion medium, the sample mass-to-dispersion medium volume ratio, as well as the parameters related to the ultrasound-assisted emulsification (sonication amplitude and treatment time) were exhaustively studied. Only 1 min of ultrasonic shaking and a dispersion medium containing 0.5% (w/v) of SDS+3% (v/v) of HNO(3) or HCl allows obtaining a stable emulsion at least for 3 months. Thermal programs, nebulization of emulsions, speed of pumps and concentration of reagents used in cold vapour generation were optimized. Calibration using aqueous standards was feasible in all cases. Calibration by the standard addition method and recovery studies was also applied for validation. Microwave-assisted digestion and Inductively Coupled Plasma Mass Spectrometry were used for comparison purposes. Relative standard deviations from analysis of five independent emulsions were less than 9% in all cases.

  16. Modern Methodology and Techniques Aimed at Developing the Environmentally Responsible Personality

    ERIC Educational Resources Information Center

    Ponomarenko, Yelena V.; Zholdasbekova, Bibisara A.; Balabekov, Aidarhan T.; Kenzhebekova, Rabiga I.; Yessaliyev, Aidarbek A.; Larchenkova, Liudmila A.

    2016-01-01

    The article discusses the positive impact of an environmentally responsible individual as the social unit able to live in harmony with the natural world, himself/herself and other people. The purpose of the article is to provide theoretical substantiation of modern teaching methods. The authors considered the experience of philosophy, psychology,…

  17. Accuracy of velocity and shear rate measurements using pulsed Doppler ultrasound: a comparison of signal analysis techniques.

    PubMed

    Markou, C P; Ku, D N

    1991-01-01

    An experimental investigation was instituted to evaluate the performance of Doppler ultrasound signal processing techniques for measuring fluid velocity under well-defined flow conditions using a 10-MHz multigated pulsed ultrasound instrument. Conditions of fully developed flow in a rigid, circular tube were varied over a Reynolds number range between 500 and 8000. The velocity across the tube was determined using analog and digital zero crossing detectors and three digital spectrum estimators. Determination of the Doppler frequency from analog or digital zero crossing detectors gave accurate velocity values for laminar and moderately turbulent flow away from the wall (0.969 less than or equal to r less than or equal to 0.986). Three digital spectrum estimators, Fast Fourier Transform, Burg autoregressive method, and minimum variance method, were slightly more accurate than the zero crossing detector (0.984 less than or equal to r less than or equal to 0.994), especially at points close to the walls and with higher levels of turbulence. Steep velocity gradients and transit-time-effects from high velocities produced significantly larger errors in velocity measurement. Wall shear rate estimates were most precise when calculated using the position of the wall and two velocity points. The calculated wall shears were within 20%-30% of theoretically predicted values.

  18. Characterization of thyroid cancer in mouse models using high-frequency quantitative ultrasound techniques.

    PubMed

    Lavarello, Roberto J; Ridgway, William R; Sarwate, Sandhya S; Oelze, Michael L

    2013-12-01

    Currently, the evaluation of thyroid cancer relies on the use of fine-needle aspiration biopsy, as non-invasive imaging methods do not provide sufficient levels of accuracy for the diagnosis of this disease. In this study, the potential of quantitative ultrasound methods for characterization of thyroid tissues was studied using a rodent model ex vivo. A high-frequency ultrasonic scanning system (40 MHz) was used to scan thyroids extracted from mice that had spontaneously developed thyroid lesions (cancerous or benign). Three sets of mice were acquired having different predispositions to developing three thyroid anomalies: C-cell adenoma, papillary thyroid carcinoma (PTC) and follicular variant papillary thyroid carcinoma (FV-PTC). A fourth set of mice that did not develop thyroid anomalies (normal mice) were used as controls. The backscatter coefficient was estimated from excised thyroid lobes the different mice. From the backscatter coefficient versus frequency (25-45 MHz), the effective scatterer diameter (ESD) and effective acoustic concentration (EAC) were estimated. From the envelope of the backscattered signal, the homodyned K distribution was used to estimate the k parameter (ratio of coherent to incoherent signal energy) and the μ parameter (number of scatterers per resolution cell). Statistically significant differences were observed between cancerous thyroids and normal thyroids based on the ESD, EAC and μ parameters. The mean ESD values were 18.0 ± 0.92, 15.9 ± 0.81 and 21.5 ± 1.80 μm for the PTC, FV-PTC and normal thyroids, respectively. The mean EAC values were 59.4 ± 1.74, 62.7 ± 1.61 and 52.9 ± 3.42 dB (mm(-3)) for the PTC, FV-PTC and normal thyroids, respectively. The mean μ values were 2.55 ± 0.37, 2.59 ± 0.43 and 1.56 ± 0.99 for the PTC, FV-PTC and normal thyroids, respectively. Statistically significant differences were observed between cancerous thyroids and C-cell adenomas based on the ESD and EAC parameters, with an estimated ESD

  19. [Ultrasound and color Doppler in nephrology. Physical and technical principles].

    PubMed

    Meola, Mario; Petrucci, Ilaria

    2012-01-01

    Sonography is an imaging technique that generates tomographic images using ultrasound. The sound constitutes mechanical energy transmitted in a medium by pressure waves. Sound waves with frequencies greater than 20 kHz are called ultrasounds. Diagnostic ultrasounds use frequencies from 1 to 20 MHz. Ultrasound equipment is composed of a scanner, an image monitor, and different transducers that transform acoustic energy into electrical signals and electrical energy into acoustic energy (piezoelectric effect). The spatial resolution defines the minimum distance between two reflectors or echogenic regions that can be imaged as separate reflectors. The spatial resolution is mainly determined by the array design (linear, curved and sectorial) and by the operative system of the transducer. Modern ultrasound machines are very sophisticated medical devices that often support many transducers, imaging modes and display devices. The scan converter memory is the device in which images are formed and then presented to the monitor and to the hard copy devices.

  20. Evaluation of cost-effectiveness from the funding body's point of view of ultrasound-guided central venous catheter insertion compared with the conventional technique.

    PubMed

    Noritomi, Danilo Teixeira; Zigaib, Rogério; Ranzani, Otavio T; Teich, Vanessa

    2016-01-01

    To evaluate the cost-effectiveness, from the funding body's point of view, of real-time ultrasound-guided central venous catheter insertion compared to the traditional method, which is based on the external anatomical landmark technique. A theoretical simulation based on international literature data was applied to the Brazilian context, i.e., the Unified Health System (Sistema Único de Saúde - SUS). A decision tree was constructed that showed the two central venous catheter insertion techniques: real-time ultrasonography versus external anatomical landmarks. The probabilities of failure and complications were extracted from a search on the PubMed and Embase databases, and values associated with the procedure and with complications were taken from market research and the Department of Information Technology of the Unified Health System (DATASUS). Each central venous catheter insertion alternative had a cost that could be calculated by following each of the possible paths on the decision tree. The incremental cost-effectiveness ratio was calculated by dividing the mean incremental cost of real-time ultrasound compared to the external anatomical landmark technique by the mean incremental benefit, in terms of avoided complications. When considering the incorporation of real-time ultrasound and the concomitant lower cost due to the reduced number of complications, the decision tree revealed a final mean cost for the external anatomical landmark technique of 262.27 Brazilian reals (R$) and for real-time ultrasound of R$187.94. The final incremental cost of the real-time ultrasound-guided technique was -R$74.33 per central venous catheter. The incremental cost-effectiveness ratio was -R$2,494.34 due to the pneumothorax avoided. Real-time ultrasound-guided central venous catheter insertion was associated with decreased failure and complication rates and hypothetically reduced costs from the view of the funding body, which in this case was the SUS.

  1. Evaluation of cost-effectiveness from the funding body's point of view of ultrasound-guided central venous catheter insertion compared with the conventional technique

    PubMed Central

    Noritomi, Danilo Teixeira; Zigaib, Rogério; Ranzani, Otavio T.; Teich, Vanessa

    2016-01-01

    Objective To evaluate the cost-effectiveness, from the funding body's point of view, of real-time ultrasound-guided central venous catheter insertion compared to the traditional method, which is based on the external anatomical landmark technique. Methods A theoretical simulation based on international literature data was applied to the Brazilian context, i.e., the Unified Health System (Sistema Único de Saúde - SUS). A decision tree was constructed that showed the two central venous catheter insertion techniques: real-time ultrasonography versus external anatomical landmarks. The probabilities of failure and complications were extracted from a search on the PubMed and Embase databases, and values associated with the procedure and with complications were taken from market research and the Department of Information Technology of the Unified Health System (DATASUS). Each central venous catheter insertion alternative had a cost that could be calculated by following each of the possible paths on the decision tree. The incremental cost-effectiveness ratio was calculated by dividing the mean incremental cost of real-time ultrasound compared to the external anatomical landmark technique by the mean incremental benefit, in terms of avoided complications. Results When considering the incorporation of real-time ultrasound and the concomitant lower cost due to the reduced number of complications, the decision tree revealed a final mean cost for the external anatomical landmark technique of 262.27 Brazilian reals (R$) and for real-time ultrasound of R$187.94. The final incremental cost of the real-time ultrasound-guided technique was -R$74.33 per central venous catheter. The incremental cost-effectiveness ratio was -R$2,494.34 due to the pneumothorax avoided. Conclusion Real-time ultrasound-guided central venous catheter insertion was associated with decreased failure and complication rates and hypothetically reduced costs from the view of the funding body, which in this

  2. Magnetic Resonance Imaging-Ultrasound Fusion-Guided Prostate Biopsy: Review of Technology, Techniques, and Outcomes

    PubMed Central

    Kongnyuy, Michael; George, Arvin K.; Rastinehad, Ardeshir R.; Pinto, Peter A.

    2016-01-01

    Transrectal ultrasound (TRUS)-guided (12–14 core) systematic biopsy of the prostate is the recommended standard for patients with suspicion of prostate cancer (PCa). Advances in imaging have led to the application of magnetic resonance imaging (MRI) for the detection of PCa with subsequent development of software-based co-registration allowing for the integration of MRI with real-time TRUS during prostate biopsy. A number of fusion-guided methods and platforms are now commercially available with common elements in image and analysis and planning. Implementation of fusion-guided prostate biopsy has now been proven to improve the detection of clinically significant PCa in appropriately selected patients. PMID:26902626

  3. Targeted drug delivery across the blood–brain barrier using ultrasound technique

    PubMed Central

    Deng, Cheri X

    2011-01-01

    Effective delivery of therapeutic agents into the brain can greatly improve the treatments of neurological and neurodegenerative diseases. Application of focused ultrasound facilitated by microbubbles has shown the potential to deliver drugs across the blood–brain barrier into targeted sites within the brain noninvasively. This review provides a summary of the technological background and principle, highlights of recent significant developments and research progress, as well as a critical commentary on the challenges and future directions in the field. This review also outlines and discusses the tasks that researchers face in order to successfully translate the technology into a clinical reality, including obtaining improved understanding of the mechanisms, demonstration of therapeutic efficacy and safety for specific applications, and development of methodology for rational design to achieve optimized and consistent outcome. PMID:21785679

  4. Characterization of biomechanical properties of agar based tissue mimicking phantoms for ultrasound stiffness imaging techniques.

    PubMed

    Manickam, Kavitha; Machireddy, Ramasubba Reddy; Seshadri, Suresh

    2014-07-01

    Pathological changes of the body have been observed to change the mechanical properties of soft tissue types which can be imaged by ultrasound elastography. Though initial clinical results using ultrasound elastography in detection of tumors are promising, quantification of signal to noise ratio, resolution and strain image patterns are the best achieved under a controlled study using phantoms with similar biomechanical properties of normal and abnormal tissues. The purpose of this work is to characterize the biomechanical properties of agar based tissue mimicking phantoms by varying the agar concentration from 1.7 to 6.6% by weight and identify the optimum property to be used in classification of cancerous tissues. We performed quasi-static uniaxial compression test under a strain rate of 0.5mm/min up to 15% strain and measured Young's modulus of phantom samples which are from 50kPa to 450kPa. Phantoms show nonlinear stress-strain characteristics at finite strain which were characterized using hyperelastic parameters by fitting Neo-Hookean, Mooney Rivlin, Ogden and Veronda Westmann models. We also investigated viscoelastic parameters of the samples by conducting oscillatory shear rheometry at various precompression levels (2-5%). Loss modulus values are always less than storage modulus which represents the behavior of soft tissues. The increase in agar concentration increases the shear modulus of the samples as well as decreases the linear viscoelastic region. The results suggest that dynamic shear modul are more promising than linear and nonlinear elastic modul in differentiation of various classes of abnormal tissues. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Application of enhanced modern structured analysis techniques to Space Station Freedom electric power system requirements

    NASA Technical Reports Server (NTRS)

    Biernacki, John; Juhasz, John; Sadler, Gerald

    1991-01-01

    A team of Space Station Freedom (SSF) system engineers are in the process of extensive analysis of the SSF requirements, particularly those pertaining to the electrical power system (EPS). The objective of this analysis is the development of a comprehensive, computer-based requirements model, using an enhanced modern structured analysis methodology (EMSA). Such a model provides a detailed and consistent representation of the system's requirements. The process outlined in the EMSA methodology is unique in that it allows the graphical modeling of real-time system state transitions, as well as functional requirements and data relationships, to be implemented using modern computer-based tools. These tools permit flexible updating and continuous maintenance of the models. Initial findings resulting from the application of EMSA to the EPS have benefited the space station program by linking requirements to design, providing traceability of requirements, identifying discrepancies, and fostering an understanding of the EPS.

  6. Modern surgical techniques for management of soft tissue sarcomas involving the spine: outcomes and complications.

    PubMed

    Mattei, Tobias A; Teles, Alisson R; Mendel, Ehud

    2015-04-01

    Several types of soft tissue sarcomas may locally extend to the spine. The best therapeutic strategy for such lesions strongly depends on the histological diagnosis. In this article the authors provide an up-to-date review of current guidelines regarding the management of soft tissue sarcomas involving the spine. Special attention is given to outcomes and complications of modern surgical series in order to highlight current challenges in the management of such lesions. © 2014 Wiley Periodicals, Inc.

  7. Socio-cultural inhibitors to use of modern contraceptive techniques in rural Uganda: a qualitative study.

    PubMed

    Kabagenyi, Allen; Reid, Alice; Ntozi, James; Atuyambe, Lynn

    2016-01-01

    Family planning is one of the cost-effective strategies in reducing maternal and child morbidity and mortality rates. Yet in Uganda, the contraceptive prevalence rate is only 30% among married women in conjunction with a persistently high fertility rate of 6.2 children per woman. These demographic indicators have contributed to a high population growth rate of over 3.2% annually. This study examines the role of socio-cultural inhibitions in the use of modern contraceptives in rural Uganda. This was a qualitative study conducted in 2012 among men aged 15-64 and women aged 15-49 in the districts of Mpigi and Bugiri in rural Uganda. Eighteen selected focus group discussions (FGDs), each internally homogeneous, and eight in-depth interviews (IDIs) were conducted among men and women. Data were collected on sociocultural beliefs and practices, barriers to modern contraceptive use and perceptions of and attitudes to contraceptive use. All interviews were tape recoded, translated and transcribed verbatim. All the transcripts were coded, prearranged into categories and later analyzed using a latent content analysis approach, with support of ATLAS.ti qualitative software. Suitable quotations were used to provide in-depth explanations of the findings. Three themes central in hindering the uptake of modern contraceptives emerged: (i) persistence of socio-cultural beliefs and practices promoting births (such as polygamy, extending family lineage, replacement of the dead, gender-based violence, power relations and twin myths). (ii) Continued reliance on traditional family planning practices and (iii) misconceptions and fears about modern contraception. Sociocultural expectations and values attached to marriage, women and child bearing remain an impediment to using family planning methods. The study suggests a need to eradicate the cultural beliefs and practices that hinder people from using contraceptives, as well as a need to scale-up family planning services and sensitization

  8. Socio-cultural inhibitors to use of modern contraceptive techniques in rural Uganda: a qualitative study

    PubMed Central

    Kabagenyi, Allen; Reid, Alice; Ntozi, James; Atuyambe, Lynn

    2016-01-01

    Introduction Family planning is one of the cost-effective strategies in reducing maternal and child morbidity and mortality rates. Yet in Uganda, the contraceptive prevalence rate is only 30% among married women in conjunction with a persistently high fertility rate of 6.2 children per woman. These demographic indicators have contributed to a high population growth rate of over 3.2% annually. This study examines the role of socio-cultural inhibitions in the use of modern contraceptives in rural Uganda. Methods This was a qualitative study conducted in 2012 among men aged 15-64 and women aged 15-49 in the districts of Mpigi and Bugiri in rural Uganda. Eighteen selected focus group discussions (FGDs), each internally homogeneous, and eight in-depth interviews (IDIs) were conducted among men and women. Data were collected on sociocultural beliefs and practices, barriers to modern contraceptive use and perceptions of and attitudes to contraceptive use. All interviews were tape recoded, translated and transcribed verbatim. All the transcripts were coded, prearranged into categories and later analyzed using a latent content analysis approach, with support of ATLAS.ti qualitative software. Suitable quotations were used to provide in-depth explanations of the findings. Results Three themes central in hindering the uptake of modern contraceptives emerged: (i) persistence of socio-cultural beliefs and practices promoting births (such as polygamy, extending family lineage, replacement of the dead, gender-based violence, power relations and twin myths). (ii) Continued reliance on traditional family planning practices and (iii) misconceptions and fears about modern contraception. Conclusion Sociocultural expectations and values attached to marriage, women and child bearing remain an impediment to using family planning methods. The study suggests a need to eradicate the cultural beliefs and practices that hinder people from using contraceptives, as well as a need to scale

  9. Search of Superfluidity of Solid 4He in a Porous Vycor Glass by Means of the Ultrasound Technique

    NASA Astrophysics Data System (ADS)

    Kobayashi, T.; Fukazawa, S.; Taniguchi, J.; Suzuki, M.; Shirahama, K.

    2006-09-01

    Kim and Chan have reported that solid 4He shows a reduction of the rotational moment of inertia below 0.2 K, which suggests an onset of superfluidity. Ultrasound should be sensitive to mass decoupling caused by superfluidity. If a superfluid component exists, the sound velocity of a porous material filled with solid 4He could increase. We have carried out ultrasonic measurements for a porous Vycor glass filled with solid 4He. Since the reported "critical velocity" is very low, we have adopted a continuous wave resonance technique which realizes the oscillating velocity less than 1 × 10-7 m/s. The resolution of the sound velocity is 10-5 for small oscillating velocities, and is enough to detect the expected mass decoupling. Although the present experimental conditions are rather limited, no signature of supersolid has been observed.

  10. Physiological patterns during practice of the Transcendental Meditation technique compared with patterns while reading Sanskrit and a modern language.

    PubMed

    Travis, F; Olson, T; Egenes, T; Gupta, H K

    2001-07-01

    This study tested the prediction that reading Vedic Sanskrit texts, without knowledge of their meaning, produces a distinct physiological state. We measured EEG, breath rate, heart rate, and skin conductance during: (1) 15-min Transcendental Meditation (TM) practice; (2) 15-min reading verses of the Bhagavad Gita in Sanskrit; and (3) 15-min reading the same verses translated in German, Spanish, or French. The two reading conditions were randomly counterbalanced, and subjects filled out experience forms between each block to reduce carryover effects. Skin conductance levels significantly decreased during both reading Sanskrit and TM practice, and increased slightly during reading a modern language. Alpha power and coherence were significantly higher when reading Sanskrit and during TM practice, compared to reading modern languages. Similar physiological patterns when reading Sanskrit and during practice of the TM technique suggests that the state gained during TM practice may be integrated with active mental processes by reading Sanskrit.

  11. Ultrasound-Guided Percutaneous Removal of Wooden Foreign Bodies in the Extremities with Hydro-Dissection Technique

    PubMed Central

    Park, Hee Jin; Lee, So Yeon; Son, Eun Seok; Chung, Eun Chul; Rho, Myung Ho; Lee, Sun Joo

    2015-01-01

    Objective We described the technique of ultrasound (US)-guided percutaneous removal of the foreign bodies (FB) with hydro-dissection in the radiologic department and presented video files of several cases. Materials and Methods Four patients referred to the radiology department for US evaluation and US-guided percutaneous removal of the FBs in the upper and lower extremities between November, 2006 and November, 2013 were included in this study. The procedures started with US evaluation for the exact location and shape of the FB. A 5 mm-sized skin incision was made at the site of the nearest point from the FB where no passing arteries or tendons were present. We adopted a hydrodissection technique to separate the FB from adjacent tissue using a 2% lidocaine solution. Injected anesthetics detached the FBs from surrounding tissue and thereby facilitated removal. After the tip of the mosquito forceps reached the FB, the wooden FBs were removed. Results The mean time required for the entire procedure was approximately 20 minutes. There were no significant complications during the US-guided removal or long-term complications after the procedure. All 4 FBs were successfully removed from the soft tissue under US guidance. Conclusion Ultrasound-guided percutaneous removal of the FBs with hydro-dissection in the radiology department is a less invasive and safe method over surgical removal in the operating room. Additionally, the use of a guide wire and serial dilator may help minimize soft tissue injury and facilitate the introduction of forceps. PMID:26576123

  12. SIMMAX: A modern analog technique to deduce Atlantic sea surface temperatures from planktonic foraminifera in deep-sea sediments

    NASA Astrophysics Data System (ADS)

    Pflaumann, Uwe; Duprat, Josette; Pujol, Claude; Labeyrie, Laurent D.

    1996-02-01

    We present a data set of 738 planktonic foraminiferal species counts from sediment surface samples of the eastern North Atlantic and the South Atlantic between 87°N and 40°S, 35°E and 60°W including published Climate: Long-Range Investigation, Mapping, and Prediction (CLIMAP) data. These species counts are linked to Levitus's [1982] modern water temperature data for the four caloric seasons, four depth ranges (0, 30, 50, and 75 m), and the combined means of those depth ranges. The relation between planktonic foraminiferal assemblages and sea surface temperature (SST) data is estimated using the newly developed SIMMAX technique, which is an acronym for a modern analog technique (MAT) with a similarity index, based on (1) the scalar product of the normalized faunal percentages and (2) a weighting procedure of the modern analog's SSTs according to the inverse geographical distances of the most similar samples. Compared to the classical CLIMAP transfer technique and conventional MAT techniques, SIMMAX provides a more confident reconstruction of paleo-SSTs (correlation coefficient is 0.994 for the caloric winter and 0.993 for caloric summer). The standard deviation of the residuals is 0.90°C for caloric winter and 0.96°C for caloric summer at 0-m water depth. The SST estimates reach optimum stability (standard deviation of the residuals is 0.88°C) at the average 0- to 75-m water depth. Our extensive database provides SST estimates over a range of -1.4 to 27.2°C for caloric winter and 0.4 to 28.6°C for caloric summer, allowing SST estimates which are especially valuable for the high-latitude Atlantic during glacial times. An electronic supplement of this material may be obtained on adiskette or Anonymous FTP from KOSMOS.AGU.ORG. (LOGIN toAGU's FTP account using ANONYMOUS as the username and GUESTas the password. Go to the right directory by typing CD APPEND. TypeLS to see what files are available. Type GET and the name of the file toget it. Finally type EXIT to

  13. Characterization of thyroid cancer in mouse models using high-frequency quantitative ultrasound techniques

    PubMed Central

    Lavarello, R. J.; Ridgway, W. R.; Sarwate, S.; Oelze, M. L.

    2013-01-01

    Currently, the evaluation of thyroid cancer relies on the use of fine needle aspiration biopsy as non-invasive imaging methods do not provide sufficient levels of accuracy for the diagnosis of this disease. In this study, the potential of quantitative ultrasound methods for characterizing thyroid tissues was studied using a rodent model ex vivo. A high-frequency ultrasonic scanning system (40 MHz) was used to scan thyroids extracted from mice that had spontaneously developed thyroid lesions (cancerous or benign). Three sets of mice were acquired having different predispositions to developing thyroid anomalies (a C-cell adenoma, a papillary thyroid carcinoma (PTC), and a follicular variant papillary thyroid carcinoma (FV-PTC)). A fourth set of mice did not develop thyroid anomalies (normal mice) and were used as controls. The backscatter coefficient was estimated from excised thyroid lobes for the different mice. From the backscatter coefficient versus frequency (25 to 45 MHz), the effective scatterer diameter (ESD) and effective acoustic concentration (EAC) were estimated. From the envelope of the backscattered signal, the homodyned K distribution was used to estimate the k parameter (ratio of coherent to incoherent signal energy) and the μ parameter (number of scatterers per resolution cell). Statistically significant differences were observed between the malignant thyroids and the normal thyroids based on the ESD, EAC and μ parameters. The mean values of the ESDs were 18.0 ± 0.92, 15.9 ± 0.81, and 21.5 ± 1.80 µm for the PTC, FV-PTC and the normal thyroids, respectively. The mean values of the EACs were 59.4 ± 1.74, 62.7 ± 1.61, and 52.9 ± 3.42 dB (mm−3) for the PTC, FV-PTC and the normal thyroids, respectively. The mean values of the μ parameters were 2.55 ± 0.37, 2.59 ± 0.43, and 1.56 ± 0.99 for the PTC, FV-PTC and the normal thyroids, respectively. Statistically significant differences were observed between the malignant thyroids and the C

  14. 3D goes digital: from stereoscopy to modern 3D imaging techniques

    NASA Astrophysics Data System (ADS)

    Kerwien, N.

    2014-11-01

    In the 19th century, English physicist Charles Wheatstone discovered stereopsis, the basis for 3D perception. His construction of the first stereoscope established the foundation for stereoscopic 3D imaging. Since then, many optical instruments were influenced by these basic ideas. In recent decades, the advent of digital technologies revolutionized 3D imaging. Powerful readily available sensors and displays combined with efficient pre- or post-processing enable new methods for 3D imaging and applications. This paper draws an arc from basic concepts of 3D imaging to modern digital implementations, highlighting instructive examples from its 175 years of history.

  15. Technical note: A novel technique to assess internal body fat of cattle by using real-time ultrasound.

    PubMed

    Ribeiro, F R B; Tedeschi, L O; Stouffer, J R; Carstens, G E

    2008-03-01

    The objectives of this study were to describe a system to assess KPH fat by using real-time ultrasound (RTU) and to develop equations to predict total physical separable internal fat (IFAT) based on ultrasound measurements. Data for this study were obtained from 24 Angus steers fed either hay- or corn-based diets during the backgrounding phase. Steers were serially slaughtered in 3 groups: at weaning (baseline), then at 4 and 8 mo after weaning. A fourth group was composed of 4 steers from the hay-fed group that were slaughtered at approximately 10 mo after weaning. The RTU measurements were collected every 2 mo, with a preslaughter scan approximately 7 d before the slaughter time. The RTU measurements consisted of 12th- to 13th-rib backfat thickness, 12th to 13th ribeye area, percentage of intramuscular fat, and kidney fat depth, which was measured in a cross-sectional image collected between the first lumbar vertebra and the 13th rib. For kidney fat, the ultrasound probe was placed on the flank region approximately 15 cm from the midline of the animal. Images were stored in the ultrasound console, and measurements were taken between the ventral part of the iliocostalis muscle and the end of the KPH fat at the chute side. The relationship between carcass and ultrasound measurements in the depths of kidney fat (cKFd and uKFd, respectively) had an r(2) of 0.93, with a root mean square error (RMSE) of 1.14 cm. An allometric regression between carcass KPH weight (cKPHwt) and cKFd was identified, and the untransformed regression had an r(2) of 0.96. The linear regression between total IFAT and cKPHwt had an r(2) of 0.97, with an RMSE of 2.67 kg. Therefore, a system was developed to predict IFAT from uKFd measurements by combining these equations. Additionally, a single linear regression between IFAT and uKFd measurements was developed (r(2) = 0.89, RMSE = 5.32 kg). Even though the system of equations had a lower RMSE of prediction and greater r(2) compared with the

  16. Bone micro-damage assessment using non-linear resonant ultrasound spectroscopy (NRUS) techniques: a feasibility study.

    PubMed

    Muller, M; Tencate, J A; Darling, T W; Sutin, A; Guyer, R A; Talmant, M; Laugier, P; Johnson, P A

    2006-12-22

    Non-linear resonant ultrasound spectroscopy (NRUS) is a technique exploiting the significant non-linear behavior of damaged materials, related to the presence of damage. This study shows for the first time the feasibility of this technique for damage assessment in bone. Two samples of bovine cortical bone were subjected to a progressive damage experiment. Damage accumulation was progressively induced in the samples by mechanical testing. For independent assessment of damage, X-ray CT imaging was performed at each damage step, but only helped in the detection of the prominent cracks. Synchrotron micro-CT imaging and histology using epifluorescence microscopy were performed in one of the two samples at the last damage step and allowed detection of micro-cracks for this step. As the quantity of damage accumulation increased, NRUS revealed a corresponding increase in the non-linear response. The measured change in non-linear response is much more sensitive than the change in elastic modulus. The results suggest that NRUS could be a potential tool for micro-damage assessment in bone. Further work has to be carried out for a better understanding of the physical nature of damaged bone, and for the ultimate goal of in vivo implementation of the technique where bone access will be a challenging problem.

  17. A novel ultrasound technique for detection of osteochondral defects in the ankle joint: a parametric and feasibility study.

    PubMed

    Sarkalkan, Nazli; Loeve, Arjo J; van Dongen, Koen W A; Tuijthof, Gabrielle J M; Zadpoor, Amir A

    2014-12-24

    (Osteo)chondral defects (OCDs) in the ankle are currently diagnosed with modalities that are not convenient to use in long-term follow-ups. Ultrasound (US) imaging, which is a cost-effective and non-invasive alternative, has limited ability to discriminate OCDs. We aim to develop a new diagnostic technique based on US wave propagation through the ankle joint. The presence of OCDs is identified when a US signal deviates from a reference signal associated with the healthy joint. The feasibility of the proposed technique is studied using experimentally-validated 2D finite-difference time-domain models of the ankle joint. The normalized maximum cross correlation of experiments and simulation was 0.97. Effects of variables relevant to the ankle joint, US transducers and OCDs were evaluated. Variations in joint space width and transducer orientation made noticeable alterations to the reference signal: normalized root mean square error ranged from 6.29% to 65.25% and from 19.59% to 8064.2%, respectively. The results suggest that the new technique could be used for detection of OCDs, if the effects of other parameters (i.e., parameters related to the ankle joint and US transducers) can be reduced.

  18. Monitoring of HIFU thermal damage using integrated photoacoustic imaging and high intensity focused ultrasound technique

    NASA Astrophysics Data System (ADS)

    Cui, Huizhong; Yang, Xinmai

    2011-03-01

    In this study, we applied an integrated photoacoustic imaging (PAI) and high intensity focused ultrasound (HIFU) system to noninvasively monitor the thermal damage due to HIFU ablation in vivo. A single-element, spherically focused ultrasonic transducer, with a central frequency of 5MHz, was used to generate a HIFU area in soft tissue. Photoacoustic signals were detected by the same ultrasonic transducer before and after HIFU treatments using different wavelengths. The feasibility of combined contrast imaging and treatment of solid tumor in vivo by the integrated PAI and HIFU system was also studied. Gold nanorods were used to enhance PAI during the imaging of a CT26 tumor, which was subcutaneously inoculated on the hip of a BALB/c mouse. Subsequently, the CT26 tumor was ablated by HIFU with the guidance of photoacoustic images. Our results suggested that the tumor was clearly visible on photoacoustic images after the injection of gold nanorods and was ablated by HIFU. In conclusion, PAI may potentially be used for monitoring HIFU thermal lesions with possible diagnosis and treatment of solid tumors.

  19. The use of a needle guide kit improves the stability of ultrasound-guided techniques.

    PubMed

    Ueshima, Hironobu; Kitamura, Akira

    2015-10-01

    A needle guide kit will be able to improve visibility on ultrasonic images. We examined the degree of stability using a SIVA guide. The SIVA guide is a needle guide kit in which the angle is not restricted, allowing the puncture to be made at any angle. We punctured the Blue Phantom™ with a high-frequency linear probe with a SIVA guide and measured the intensities of the needle at depths of 0.5, 1.0, 1.5, and 2.0 cm on the ultrasound image with Image J software. We set all punctures angles at 45 degrees from the Blue Phantom™. Six anesthesiologists with >7 years experience performed two punctures-one case was punctured with a SIVA guide and the other was punctured without a SIVA guide. Some significant differences were noted in the results between the two punctures at depths of 1.0, 1.5, and 2.0 cm. We were able to prove that the use of a needle guide kit could improve visibility on ultrasonic images.

  20. Fast characterization of two ultrasound longitudinal waves in cancellous bone using an adaptive beamforming technique.

    PubMed

    Taki, Hirofumi; Nagatani, Yoshiki; Matsukawa, Mami; Mizuno, Katsunori; Sato, Toru

    2015-04-01

    The received signal in through-transmission ultrasound measurements of cancellous bone consists of two longitudinal waves, called the fast and slow waves. Analysis of these fast and slow waves may reveal characteristics of the cancellous bone that would be good indicators of osteoporosis. Because the two waves often overlap, decomposition of the received signal is an important problem in the characterization of bone quality. This study proposes a fast and accurate decomposition method based on the frequency domain interferometry imaging method with a modified wave transfer function that uses a phase rotation parameter. The proposed method accurately characterized the fast and slow waves in the experimental study, and the residual intensity, which was normalized with respect to the received signal intensity, was less than -20 dB over the bone specimen thickness range from 6 to 15 mm. In the simulation study, the residual intensity was less than -20 dB over the specimen thickness range from 3 to 8 mm. Decomposition of a single received signal takes only 5 s using a laptop personal computer with a single central processing unit. The proposed method has great potential to provide accurate and rapid measurements of indicators of osteoporosis in cancellous bone.

  1. Efficacy of topical 0.05% retinaldehyde in skin aging by ultrasound and rheological techniques.

    PubMed

    Diridollou, S; Vienne, M P; Alibert, M; Aquilina, C; Briant, A; Dahan, S; Denis, P; Launais, B; Turlier, V; Dupuy, P

    1999-01-01

    The natural precursor of retinoic acid, i.e. retinaldehyde, has been proven to exert retinoid activities. The aim of this prospective instrument study was to determine the effect of topical retinaldehyde 0.05% on the physical properties of aging skin. This was performed using two devices, namely a high-resolution (70-80 microm) ultrasound scanner, which visualizes the thickness of both the epidermis and the dermis, and an echorheometer, which assesses the stiffness and elasticity of the skin by suction. In a 1-year study, 21 patients applied retinaldehyde cream 0.05% on the face, while another group of 19 volunteers were only treated with an emollient (control group). Epidermal and dermal thicknesses were measured on the forehead and temple, and stiffness and elasticity were measured on the forehead only. All the instrumental parameters were assessed at baseline and at the end of treatment. Compared to the control group, retinaldehyde treatment induced a significant increase in epidermal thickness of the temple, as well as in cutaneous elasticity (p < 0. 01). Similarly, retinaldehyde treatment tended to increase dermal thickness and reduce cutaneous stiffness, but no statistical difference could be observed between the two groups. Taken together, the results further suggest that retinaldehyde has counteracting effects on skin aging

  2. Last interglacial sea-surface temperature estimates from the California margin; improvements to the modern analog technique

    USGS Publications Warehouse

    Dowsett, Harry J.; Poore, Richard Z.

    1999-01-01

    Total faunal analyses of planktic foraminifer assemblages are used to derive sea surface temperature estimates for the last interglacial from Ocean Drilling Program Sites 1018 and 1020 off northern and central California. Foraminifer assemblage data were transformed to sea-surface temperature (SST) estimates by using the modern analog technique (MAT). In order to improve our ability to estimate SST in this area, the coretop calibration data base used in the MAT was augmented by 13 new age-validated coretop assemblages from the U.S. Pacific Margin.

  3. The iLappSurgery taTME app: a modern adjunct to the teaching of surgical techniques.

    PubMed

    Atallah, S; Brady, R R W

    2016-09-01

    Application-based technology has emerged as a method of modern information communication, and this has been applied towards surgical training and education. It allows surgeons the ability to obtain portable and instant access to information that is otherwise difficult to deliver. The iLappSurgery Foundation has recently launched the transanal total mesorectal excision educational application (taTME app) which provides a useful adjunct, especially for surgeons interested in mastery of the taTME technique and its principles. The article provides a detailed review of the application, which has achieved a large user-base since its debut in June, 2016.

  4. Prospective study of ultrasound-guided percutaneous renal cryotherapy: case selection as an optimization factor for a technique.

    PubMed

    Rodríguez-Faba, O; Palou, J; Rosales, A; de la Torre, P; Martí, J; Palazzetti, A; Villavicencio, H

    2015-01-01

    To evaluate the technical and oncological effectiveness of ultrasound-guided percutaneous renal cryotherapy (PRC) in a selected group of patients with renal cancer. We conducted a prospective study of 28 patients with posterior-facing T1a renal tumors with middle and inferior external borders. All patients underwent ultrasound-guided PRC. Follow-up was conducted with computed tomography at 1 month and then every 6 months, with a good result defined as the total absence of contrast incorporation. We performed a descriptive and survival study using the Kaplan-Meier estimator. The 28 patients had a mean age (SD) of 68.3 (10.1) years, and the group underwent 28 procedures. The mean (SD) size of the tumors was 25.5 (7.5) mm, the mean nephrometry score was 1.41 (0.52) and the mean preoperative creatinine level was 133.5 (144.1) mmol/L. There were no intraoperative complications. In terms of postoperative complications, there was only 1 case (3.5%) of a skin lesion resulting from treating a tumor in a transplanted kidney (Clavien II). The median follow-up was 25 months, and the mean (SD) postoperative creatinine level was 135.5 (110.3) mmol/L. Two cases presented radiological recurrence (93% efficacy), with a mean time to recurrence of 12 and 19 months, respectively. There were no tumor-related deaths. Our series (the largest on PRC in our country to date) shows that, with an appropriate selection of tumors, PRC is a safe technique with minimal morbidity. Ultrasonography enables the controlled performance of the procedure and saves the patient from radiation and reduces costs. Copyright © 2013 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.

  5. Study and implementation of a novel ultrasound imaging technique combining digital beamforming with synthetical aperture.

    PubMed

    Shuguang, Zhao; Hailong, Zhao; Yanhong, Fang; Min, Tang

    2005-01-01

    Aiming at higher performances and lower cost of an ultrasonic imaging system, a novel digital imaging approach was proposed, which combines the dual beamforming technique to double frame rate with the synthetical aperture technique to halve receive channels. Besides theoretical analyses and simulations, its hardware implementation was discussed in detail, embodied and finally tested on a real ultrasonic imaging system. The experimental results show that with this approach, system cost can be remarkably reduced without lowering the frame rate and image quality.

  6. Quantitative estimation of bioclimatic parameters from presence/absence vegetation data in North America by the modern analog technique

    USGS Publications Warehouse

    Thompson, R.S.; Anderson, K.H.; Bartlein, P.J.

    2008-01-01

    The method of modern analogs is widely used to obtain estimates of past climatic conditions from paleobiological assemblages, and despite its frequent use, this method involved so-far untested assumptions. We applied four analog approaches to a continental-scale set of bioclimatic and plant-distribution presence/absence data for North America to assess how well this method works under near-optimal modern conditions. For each point on the grid, we calculated the similarity between its vegetation assemblage and those of all other points on the grid (excluding nearby points). The climate of the points with the most similar vegetation was used to estimate the climate at the target grid point. Estimates based the use of the Jaccard similarity coefficient had smaller errors than those based on the use of a new similarity coefficient, although the latter may be more robust because it does not assume that the "fossil" assemblage is complete. The results of these analyses indicate that presence/absence vegetation assemblages provide a valid basis for estimating bioclimates on the continental scale. However, the accuracy of the estimates is strongly tied to the number of species in the target assemblage, and the analog method is necessarily constrained to produce estimates that fall within the range of observed values. We applied the four modern analog approaches and the mutual overlap (or "mutual climatic range") method to estimate bioclimatic conditions represented by the plant macrofossil assemblage from a packrat midden of Last Glacial Maximum age from southern Nevada. In general, the estimation approaches produced similar results in regard to moisture conditions, but there was a greater range of estimates for growing-degree days. Despite its limitations, the modern analog technique can provide paleoclimatic reconstructions that serve as the starting point to the interpretation of past climatic conditions.

  7. Modern analytical techniques in the assessment of the authenticity of Serbian honey.

    PubMed

    Milojković Opsenica, Dušanka; Lušić, Dražen; Tešić, Živoslav

    2015-12-01

    Food authenticity in a broader sense means fulfilling chemical and physical criteria prescribed by the proposed legislation. In the case of honey authenticity, two aspects are of major concern: the manufacturing process and the labelling of final products in terms of their geographical and botanical origin. A reliable assessment of honey authenticity has been a longterm preoccupation of chemists-analysts and it usually involves the use of several criteria and chemical markers, as well as a combination of analytical and statistical (chemometric) methods. This paper provides an overview of different criteria and modern methods for the assessment of honey authenticity in the case of a statistically significant number of authentic honey samples of several botanical types from various regions of Serbia.

  8. A Course in Heterogeneous Catalysis: Principles, Practice, and Modern Experimental Techniques.

    ERIC Educational Resources Information Center

    Wolf, Eduardo E.

    1981-01-01

    Outlines a multidisciplinary course which comprises fundamental, practical, and experimental aspects of heterogeneous catalysis. The course structure is a combination of lectures and demonstrations dealing with the use of spectroscopic techniques for surface analysis. (SK)

  9. A Course in Heterogeneous Catalysis: Principles, Practice, and Modern Experimental Techniques.

    ERIC Educational Resources Information Center

    Wolf, Eduardo E.

    1981-01-01

    Outlines a multidisciplinary course which comprises fundamental, practical, and experimental aspects of heterogeneous catalysis. The course structure is a combination of lectures and demonstrations dealing with the use of spectroscopic techniques for surface analysis. (SK)

  10. Management of pudendal neuralgia using ultrasound-guided pulsed radiofrequency: a report of two cases and discussion of pudendal nerve block techniques.

    PubMed

    Hong, Myong-Joo; Kim, Yeon-Dong; Park, Jeong-Ki; Hong, Hyon-Joo

    2016-04-01

    Pudendal neuralgia is characterized by chronic pain or discomfort in the area innervated by the pudendal nerve, with no obvious cause. A successful pudendal nerve block is crucial for the diagnosis of pudendal neuralgia. Blind or fluoroscopy-guided pudendal nerve blocks have been conventionally used for diagnosis and treatment; however, ultrasound-guided pudendal nerve blocks were also reported recently. With regard to the achievement of long-term effects, although pulsed radiofrequency performed under fluoroscopic guidance has been reported, that performed under ultrasound guidance is not well reported. This report describes two cases of pudendal neuralgia that were successfully managed using ultrasound-guided pulsed radiofrequency and presents a literature review of pudendal nerve block techniques. However, in the management of chronic neuropathic pain, physicians should keep in mind that the placebo effect related to invasive approaches must not be neglected.

  11. Use of Modern Chemical Protein Synthesis and Advanced Fluorescent Assay Techniques to Experimentally Validate the Functional Annotation of Microbial Genomes

    SciTech Connect

    Kent, Stephen

    2012-07-20

    The objective of this research program was to prototype methods for the chemical synthesis of predicted protein molecules in annotated microbial genomes. High throughput chemical methods were to be used to make large numbers of predicted proteins and protein domains, based on microbial genome sequences. Microscale chemical synthesis methods for the parallel preparation of peptide-thioester building blocks were developed; these peptide segments are used for the parallel chemical synthesis of proteins and protein domains. Ultimately, it is envisaged that these synthetic molecules would be ‘printed’ in spatially addressable arrays. The unique ability of total synthesis to precision label protein molecules with dyes and with chemical or biochemical ‘tags’ can be used to facilitate novel assay technologies adapted from state-of-the art single molecule fluorescence detection techniques. In the future, in conjunction with modern laboratory automation this integrated set of techniques will enable high throughput experimental validation of the functional annotation of microbial genomes.

  12. The modernization of cooking techniques in two rural Mayan communities of Yucatán: the case of lard frying.

    PubMed

    Arroyo, Pedro; Pardío-López, Jeanette; Loria, Alvar; Fernández-García, Victoria

    2010-01-01

    The objective of this article is to provide information on cooking techniques used by two rural communities of Yucatán. We used a 24-hour recall method with 275 participants consuming 763 dishes. Dishes were classified according to cooking technique: 205 were lard-fried (27%), 169 oil-fried (22%), and 389 boiled/grilled (51%). The smaller more secluded community (San Rafael) consumed more fried dishes than the larger community (Uci) (54% versus 45%) and used more lard-frying than Uci (65% versus 46%). The more extensive use of lard in the smaller community appears to be due to fewer modernizing influences such as the availability and use of industrialized vegetable oils. Copyright © Taylor & Francis Group, LLC

  13. Indirect fluorometric detection techniques on thin layer chromatography and effect of ultrasound on gel electrophoresis

    SciTech Connect

    Yinfa, Ma.

    1990-12-10

    Thin-layer chromatography (TLC) is a broadly applicable separation technique. It offers many advantages over high performance liquid chromatography (HPLC), such as easily adapted for two-dimensional separation, for whole-column'' detection and for handling multiple samples, etc. However, due to its draggy development of detection techniques comparing with HPLC, TLC has not received the attention it deserves. Therefore, exploring new detection techniques is very important to the development of TLC. It is the principal of this dissertation to present a new detection method for TLC -- indirect fluorometric detection method. This detection technique is universal sensitive, nondestructive, and simple. This will be described in detail from Sections 1 through Section 5. Section 1 and 3 describe the indirect fluorometric detection of anions and nonelectrolytes in TLC. In Section 2, a detection method for cations based on fluorescence quenching of ethidium bromide is presented. In Section 4, a simple and interesting TLC experiment is designed, three different fluorescence detection principles are used for the determination of caffeine, saccharin and sodium benzoate in beverages. A laser-based indirect fluorometric detection technique in TLC is developed in Section 5. Section 6 is totally different from Sections 1 through 5. An ultrasonic effect on the separation of DNA fragments in agarose gel electrophoresis is investigated. 262 refs.

  14. Comparison of 2 transabdominal ultrasound image guidance techniques for prostate and prostatic fossa radiation therapy.

    PubMed

    Salter, Bill J; Szegedi, Martin; Boehm, Christine; Sarkar, Vikren; Rassiah-Szegedi, Prema; Wang, Brian; Zhao, Hui; Huang, Jessica; Huang, Long; Kokeny, Kris; Tward, Jonathan D

    Our clinic is a long-term user of a first-generation transabdominal (TA) biplanar (2.5-dimensional [2.5D]) ultrasound image guidance (USIG) system for prostate cancer treatments. We are also an early adopter and development partner for a new, second-generation, fully 3D USIG system that allows for volumetric TA localization of the prostate. This new system has been evaluated at our institution by direct comparison with the previously established first-generation TA method for prostate alignment. We compared the 2 TA-USIG methods on the same subjects and same treatment sessions. A total of 1428 fractions delivered to 41 treated patients (16 intact prostate, 25 fossa) were analyzed regarding the agreement of alignments between the 2 US positioning systems. Patients were first aligned to tattoos using treatment room lasers. TA-USIG using the 3D system was then performed to align contours derived during the computed tomography simulation process to their corresponding daily US-visualized structures. The US-3D system image guidance shifts were performed and recorded as the "initial" shifts. A 2.5D system alignment was then immediately performed using the same computed tomography derived reference contours and the indicated shifts, relative to the 3D system, were recorded as the difference between the 2 alignment methods. The average difference between the 2 TA-USIG alignments for all patients was 0.4 ± 0.7 mm, 0.7 ± 0.9 mm, and 0.5 ± 0.9 mm in the left-right, anteroposterior, and superoinferior directions, respectively. No significant difference in system agreement between intact prostate versus fossa patients was observed. Our comparison of an established 2.5D USIG method with a newer, fully 3D approach for prostate alignment of 41 different patients (1428 fractions) shows excellent agreement with each other, despite the nontrivial difference in imaging approaches. This shows that the 2 specific USIG approaches yield results that are consistent with each other, and

  15. AMS-14C analysis of modern teeth: A comparison between two sample preparation techniques

    NASA Astrophysics Data System (ADS)

    Solis, C.; Solis-Meza, E.; Morales, M. E.; Rodriguez-Ceja, M.; Martínez-Carrillo, M. A.; Garcia-Calderon, D.; Huerta, A.; Chávez, E.

    2017-09-01

    AMS-14C analysis of modern teeth has become important for forensic studies. 14C content in human teeth reflects the 14C atmospheric concentration during its formation and allows the calculation of the actual year of birth. Through AMS, it is possible to measure the 14C concentrations in a tissue with high precision. However, there is a debate about which should be the best fraction for teeth carbon dating: collagen or enamel. This work focuses on the results obtained from enamel and collagen extracted from Mexican people in order to compare them. Collagen from dental pieces donated from people older than 60-years-old have been included to understand the turnover process and usefulness of collagen to determine the date of birth. Our results indicate that when a single dental piece is available, enamel method allows the determination of the tooth formation date. Dating collagen of the same tooth helps to discriminate if the formation date belongs to the left or the right side of the peak bomb, but also corroborates, the ages obtained through enamel analysis.

  16. Practical Problems in the Cement Industry Solved by Modern Research Techniques

    ERIC Educational Resources Information Center

    Daugherty, Kenneth E.; Robertson, Les D.

    1972-01-01

    Practical chemical problems in the cement industry are being solved by such techniques as infrared spectroscopy, gas chromatography-mass spectrometry, X-ray diffraction, atomic absorption and arc spectroscopy, thermally evolved gas analysis, Mossbauer spectroscopy, transmission and scanning electron microscopy. (CP)

  17. Dysphagia Screening: Contributions of Cervical Auscultation Signals and Modern Signal-Processing Techniques.

    PubMed

    Dudik, Joshua M; Coyle, James L; Sejdić, Ervin

    2015-08-01

    Cervical auscultation is the recording of sounds and vibrations caused by the human body from the throat during swallowing. While traditionally done by a trained clinician with a stethoscope, much work has been put towards developing more sensitive and clinically useful methods to characterize the data obtained with this technique. The eventual goal of the field is to improve the effectiveness of screening algorithms designed to predict the risk that swallowing disorders pose to individual patients' health and safety. This paper provides an overview of these signal processing techniques and summarizes recent advances made with digital transducers in hopes of organizing the highly varied research on cervical auscultation. It investigates where on the body these transducers are placed in order to record a signal as well as the collection of analog and digital filtering techniques used to further improve the signal quality. It also presents the wide array of methods and features used to characterize these signals, ranging from simply counting the number of swallows that occur over a period of time to calculating various descriptive features in the time, frequency, and phase space domains. Finally, this paper presents the algorithms that have been used to classify this data into 'normal' and 'abnormal' categories. Both linear as well as non-linear techniques are presented in this regard.

  18. Practical Problems in the Cement Industry Solved by Modern Research Techniques

    ERIC Educational Resources Information Center

    Daugherty, Kenneth E.; Robertson, Les D.

    1972-01-01

    Practical chemical problems in the cement industry are being solved by such techniques as infrared spectroscopy, gas chromatography-mass spectrometry, X-ray diffraction, atomic absorption and arc spectroscopy, thermally evolved gas analysis, Mossbauer spectroscopy, transmission and scanning electron microscopy. (CP)

  19. Dysphagia Screening: Contributions of Cervical Auscultation Signals and Modern Signal-Processing Techniques

    PubMed Central

    Dudik, Joshua M.; Coyle, James L.

    2015-01-01

    Cervical auscultation is the recording of sounds and vibrations caused by the human body from the throat during swallowing. While traditionally done by a trained clinician with a stethoscope, much work has been put towards developing more sensitive and clinically useful methods to characterize the data obtained with this technique. The eventual goal of the field is to improve the effectiveness of screening algorithms designed to predict the risk that swallowing disorders pose to individual patients’ health and safety. This paper provides an overview of these signal processing techniques and summarizes recent advances made with digital transducers in hopes of organizing the highly varied research on cervical auscultation. It investigates where on the body these transducers are placed in order to record a signal as well as the collection of analog and digital filtering techniques used to further improve the signal quality. It also presents the wide array of methods and features used to characterize these signals, ranging from simply counting the number of swallows that occur over a period of time to calculating various descriptive features in the time, frequency, and phase space domains. Finally, this paper presents the algorithms that have been used to classify this data into ‘normal’ and ‘abnormal’ categories. Both linear as well as non-linear techniques are presented in this regard. PMID:26213659

  20. Modern thermoelectrochemistry.

    PubMed

    Gründler, Peter; Kirbs, Andreas; Dunsch, Lothar

    2009-08-03

    Thermoelectrochemistry as a branch of electrochemistry like photoelectrochemistry is reviewed in an integral treatment of the subject. Especially modern thermoelectrochemistry is focused on new techniques to vary the temperature as an independent variable. This review based on a definition of modern thermoelectrochemistry includes all the classical work which contributes to the formation of modern thermoelectrochemistry, among them high-temperature electrochemistry, subcritical- and supercritical electrochemistry and in-situ electrochemical calorimetry. The main focus is on modern techniques like fast electrode heating by lasers or by alternating current as well as on heating of solution spots by microwaves and related methods. Here the state of the art in modern thermoelectrochemistry is critically reviewed for the first time.

  1. Overview of Some New Techniques for Inspection: Using 1950's Physics to Solve Modern Problems

    NASA Astrophysics Data System (ADS)

    Lanza, Richard

    2007-04-01

    The goal of any inspection technique is to non-intrusively determine the presence of such materials in a manner which is consistent with not interrupting the normal scheme of commerce and which, at the same time, exhibits a high probability of detection and a low probability of false alarms. A great deal of work has been reported in the literature on neutron based techniques for the detection of explosives with by far the largest impetus coming from the requirements of the commercial aviation industry for the inspection of luggage and, to a lesser extent, cargo; for baggage, the major techniques are either x-ray based or are chemical trace detection methods which look for small traces of explosive residues. Nuclear techniques have been proposed for the detection of explosives and contraband for a number of years due to their ability to penetrate shielding and to identify the elemental composition of materials, thus leading to enhanced detection probability and lower false alarm rates. Nuclear techniques are virtually the only method which can both detect and identify the presence of fissile materials, either in the form of bulk material or assembled weapons. Some examples of current work in nuclear based systems currently under development will be discussed such as nuclear resonance radiography, nuclear resonance fluorescence, pulsed fast neutron analysis and pulsed photonuclear detection. The physical basis of these techniques is well known, the physics having been studied in the 1950's, but there remain limitations on current technology with respect to e.g. radiation sources and detectors and data acquisition methods. Accelerator-based systems often are large and are often not well suited for field use; radiation detectors often suffer from limited count rate ability, low sensitivity and poor energy resolution and data acquisition and analysis methods usually rely on analog techniques which are not always stable in field operation. Current research in basic

  2. A two-pulse technique for extracting 3rd harmonic from ultrasound contrast agent echo signal.

    PubMed

    Song, Jae-hee; Kim, Sang-min; Song, Tai-kyong

    2008-01-01

    Multi-pulse techniques like CPS (contrast pulse sequence) and TPS (triplet pulse sequence) are the most popular methods for separating the 3rd harmonic signals from received signal. Those two methods, however, transmit a pulse at least three times along each scanline with different phase and amplitude, which results in the frame rate reduction. In this paper, we propose a technique using two pulses whose phase difference is 90 degrees and a simple digital filter. The second harmonic signal is eliminated by summing two received signals as their phase difference becomes 180 degrees and then the fundamental signals are eliminated by using a digital filter. Computer simulations are performed for different values of signal bandwidths and filter specifications. The results show the maximum error is -35.5 dB compared to TPS.

  3. Suprapubic catheter insertion using an ultrasound-guided technique and literature review.

    PubMed

    Jacob, Preman; Rai, Bhavan Prasad; Todd, Alistair W

    2012-09-01

    What's known on the subject? and What does the study add? The conventional 'blind' technique for suprapubic catheter (SPC) insertion relies on adequate filling of the bladder to displace bowel away from the site of needle puncture. However, in a small percentage of patients this fails to happen, which can occasionally lead to life-threatening bowel injury. Recently published British Association of Urological Surgeons (BAUS) guidelines have recommended that ultrasonography (US) may be helpful to identify bowel loops and recommends its usage whenever possible. This paper describes the technique of US-guided needle puncture and SPC insertion to reduce the likelihood of bowel injury. The paper addresses training, equipment and logistical issues associated with this advice. We have reviewed the available publications on the outcomes from this technique and also present our experience. Suprapubic catheter (SPC) insertion is a common method of bladder drainage in contemporary urological practice. The procedure involves insertion of a sharp trocar into the bladder percutaneously, usually by palpation, percussion or cystoscopy for guidance. Although generally considered a safe procedure, the risk of bowel injury is estimated at up to 2.4% with a mortality rate of 1.8%. Recently published British Association of Urological Surgeons (BAUS) guidelines have recommended that ultrasonography (US) may be helpful to identify bowel loops and recommends its usage whenever possible. The present paper describes the use of US for SPC insertion and discusses the implications of this advice. This paper is designed to support and supplement practical techniques learnt on a course and in clinical practice. © 2012 THE AUTHORS. BJU INTERNATIONAL © 2012 BJU INTERNATIONAL.

  4. Acoustic puncture assist device™ versus conventional loss of resistance technique for thoracic paravertebral space identification: Clinical and ultrasound evaluation

    PubMed Central

    Ali, Monaz Abdulrahman; Abdellatif, Ashraf Abualhasan

    2017-01-01

    Background: Acoustic puncture assist device (APAD™) is a pressure measurement combined with a related acoustic signal that has been successfully used to facilitate epidural punctures. The principal of loss of resistance (LOR) is similar when performing paravertebral block (PVB). We investigated the usefulness of APAD™ by comparing it with the conventional LOR techniques for identifying paravertebral space (PVS). Subjects and Methods: A total of 100 women who were scheduled for elective breast surgery under general anesthesia with PVB were randomized into two equal groups. The first group (APAD group) was scheduled for PVB using APAD™. The second group (C group) was scheduled for PVB using conventional LOR technique. We recorded the success rate assessed by clinical and ultrasound findings, the time required to identify the PVS, the depth of the PVS and the number of attempts. The attending anesthesiologist was also questioned about the usefulness of the acoustic signal for detection of the PVS. Results: The incidence of successful PVB was (49) in APAD group compared to (42) in C group P < 0.05. The time required to do PVB was significantly shorter in APAD group than in C group (3.5 ± 1.35 vs. 4.1 ± 1.42) minutes. Two patients in APAD group needed two or more attempts compared to four patients in C group. The attending anesthesiologist found the acoustic signal valuable in all patients in APAD group. Conclusion: Using APAD™ compared to the conventional LOR technique showed a lower failure rate and a shorter time to identify the PVS. PMID:28217050

  5. Comparison of modern and conventional imaging techniques in establishing multiple myeloma-related bone disease: a systematic review.

    PubMed

    Regelink, Josien C; Minnema, Monique C; Terpos, Evangelos; Kamphuis, Marjolein H; Raijmakers, Pieter G; Pieters-van den Bos, Indra C; Heggelman, Ben G F; Nievelstein, Rutger-Jan; Otten, Rene H J; van Lammeren-Venema, Danielle; Zijlstra, Josee M; Arens, Anne I J; de Rooy, Jacky W; Hoekstra, Otto S; Raymakers, Reinier; Sonneveld, Pieter; Ostelo, Raymond W; Zweegman, Sonja

    2013-07-01

    This systematic review of studies compared magnetic resonance imaging (MRI), (18) F-fluorodeoxyglucose positron emission tomography (FDG-PET), FDG-PET with computerized tomography (PET-CT) and CT with whole body X-Ray (WBXR) or (whole body) CT in order to provide evidence-based diagnostic guidelines in multiple myeloma bone disease. A comprehensive search of 3 bibliographic databases was performed; methodological quality was assessed using Quality Assessment of Diagnostic Accuracy Studies (QUADAS) criteria (score 1-14). Data from 32 directly comparative studies were extracted. The mean QUADAS score was 7·1 (3-11), with quality hampered mainly by a poor description of selection and execution criteria. All index tests had a higher detection rate when compared to WBXR, with up to 80% more lesions detected by the newer imaging techniques; MRI (1·12-1·82) CT (1·04-1·33), PET (1·00-1·58) and PET-CT (1·27-1·45). However, the modern imaging techniques detected fewer lesions in the skull and ribs. In a direct comparison CT and MRI performed equally with respect to detection rate and sensitivity. This systematic review supports the International Myeloma Working Group guidelines, which recommend that WBCT can replace WBXR. In our opinion, the equal performance of MRI also indicates that it is a valuable alternative. As lesions of the skull and ribs are underdiagnosed by modern imaging techniques we advise additional X-rays of these regions. The consequences of this approach are discussed. © 2013 John Wiley & Sons Ltd.

  6. Comparison and analysis of two modern methods in the structural health monitoring techniques in aerospace

    NASA Astrophysics Data System (ADS)

    Riahi, Mohammad; Ahmadi, Alireza

    2016-04-01

    Role of air transport in the development and expansion of world trade leading to economic growth of different countries is undeniable. Continuing the world's trade sustainability without expansion of aerospace is next to impossible. Based on enormous expenses for design, manufacturing and maintenance of different aerospace structures, correct and timely diagnosis of defects in those structures to provide for maximum safety has the highest importance. Amid all this, manufacturers of commercial and even military aircrafts are after production of less expensive, lighter, higher fuel economy and nonetheless, higher safety. As such, two events has prevailed in the aerospace industries: (1) Utilization of composites for the fuselage as well as other airplane parts, (2) using modern manufacturing methods. Arrival of two these points have created the need for upgrading of the present systems as well as innovating newer methods in diagnosing and detection of defects in aerospace structures. Despite applicability of nondestructive testing (NDT) methods in aerospace for decades, due to some limitations in the defect detection's certainty, particularly for composite material and complex geometries, shadow of doubt has fallen on maintaining complete confidence in using NDT. These days, two principal approach are ahead to tackle the above mentioned problems. First, approach for the short range is the creative and combinational mean to increase the reliability of NDT and for the long run, innovation of new methods on the basis of structural health monitoring (SHM) is in order. This has led to new philosophy in the maintenance area and in some instances; field of design has also been affected by it.

  7. Chemometric experimental design based optimization techniques in capillary electrophoresis: a critical review of modern applications.

    PubMed

    Hanrahan, Grady; Montes, Ruthy; Gomez, Frank A

    2008-01-01

    A critical review of recent developments in the use of chemometric experimental design based optimization techniques in capillary electrophoresis applications is presented. Current advances have led to enhanced separation capabilities of a wide range of analytes in such areas as biological, environmental, food technology, pharmaceutical, and medical analysis. Significant developments in design, detection methodology and applications from the last 5 years (2002-2007) are reported. Furthermore, future perspectives in the use of chemometric methodology in capillary electrophoresis are considered.

  8. Right atrial and right ventricular ultrasound-guided biopsy technique in standing horses.

    PubMed

    Decloedt, A; de Clercq, D; Ven, S; van der Vekens, N; Chiers, K; van Loon, G

    2016-05-01

    Endomyocardial biopsies could be a valuable tool in equine cardiology for diagnosing myocardial disease, which is probably underdiagnosed in horses because of lack of specific diagnostic measures and limitations of currently available diagnostic methods. To describe a technique for serial right atrial and right ventricular endomyocardial biopsy in standing horses using a percutaneous approach through the jugular vein. Prospective study. Biopsy was performed in 10 healthy standing horses sedated with detomidine, under continuous electrocardiography monitoring. A 10 cm (n = 6), 45 cm (n = 1) or 98 cm (n = 3) introducer sheath was inserted into the right jugular vein. Under echocardiographic guidance, a biopsy forceps was introduced through the sheath into the right ventricle and right atrium and endomyocardial biopsies were acquired. In all horses, 3 right ventricular biopsies were obtained from the right ventricular apex and 3 right atrial biopsies were obtained from the dorsal right atrial wall near the tuberculum intervenosum. The presence of myocardial tissue was confirmed by histology. All horses showed atrial and ventricular premature depolarisations associated with acquisition of the biopsies. In 9 horses, the arrhythmia disappeared after retraction of the forceps and introducer sheath. In one horse, ventricular premature depolarisations disappeared only after 8 h. No other complications were observed. Endomyocardial biopsy of the right atrium and right ventricle could be performed in standing horses using a percutaneous approach through the jugular vein and was not associated with complications other than temporary arrhythmias. This technique may be useful for research purposes or as a diagnostic tool, although further research is needed to establish the safety of the technique in clinical patients with myocardial disease. © 2015 EVJ Ltd.

  9. Ultrasound-Guided Interventional Procedures of the Wrist and Hand: Anatomy, Indications, and Techniques.

    PubMed

    Colio, Sean W; Smith, Jay; Pourcho, Adam M

    2016-08-01

    Acute and chronic wrist and hand conditions are commonly seen by neuromuscular and musculoskeletal specialists. High-frequency diagnostic ultrasonography (US) has facilitated advances in the diagnosis and interventional management of wrist and hand disorders. US provides excellent soft tissue resolution, accessibility, portability, lack of ionizing radiation, and the ability to dynamically assess disorders and precisely guide interventional procedures. This article review the relevant anatomy, indications, and interventional techniques for common disorders of the wrist and hand, including radiocarpal joint arthritis, scaphotrapeziotrapezoidal joint arthritis, trapeziometacarpal joint arthritis, phalangeal joint arthritis, first dorsal compartment tenosynovitis, ganglion cysts, and stenosing tenosynovitis. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Ultrasound-guided percutaneous neuroplasty of the lateral femoral cutaneous nerve for the treatment of meralgia paresthetica: a case report and description of a new ultrasound-guided technique.

    PubMed

    Mulvaney, Sean W

    2011-01-01

    The lateral femoral cutaneous nerve (LFCN) can be visualized with ultrasound imaging using a high frequency linear transducer. The entrapment of the LFCN, often near the lateral aspect of the inguinal ligament, is accepted as an etiology of meralgia paresthetica (MP). This case report describes an ultrasound-guided, percutaneous technique that utilizes injected fluid to facilitate blunt dissection (or hydrodissection) to perform an external neuroplasty of the LFCN. This procedure resulted in immediate, long-term relief of pain associated with severe, chronic MP. This procedure may potentially represent an alternate treatment for patients with contraindications or partial contraindications to surgical neurolysis, nerve transection (usually described as being performed under general anesthesia), or corticosteroid injection, or in patients not responding to conservative treatment measures.

  11. Abdominal Ultrasound

    MedlinePlus

    ... Ultrasound - Abdomen Ultrasound imaging of the abdomen uses sound waves to produce pictures of the structures within ... pictures of the inside of the body using sound waves. Ultrasound imaging, also called ultrasound scanning or ...

  12. Hip Ultrasound

    MedlinePlus

    ... Index A-Z Hip Ultrasound Hip ultrasound uses sound waves to produce pictures of muscles, tendons, ligaments, ... pictures of the inside of the body using sound waves. Ultrasound imaging, also called ultrasound scanning or ...

  13. Ultrasound - Breast

    MedlinePlus

    ... Ultrasound - Breast Ultrasound imaging of the breast uses sound waves to produce pictures of the internal structures ... pictures of the inside of the body using sound waves. Ultrasound imaging, also called ultrasound scanning or ...

  14. Obstetrical Ultrasound

    MedlinePlus

    ... Index A-Z Obstetric Ultrasound Obstetric ultrasound uses sound waves to produce pictures of a baby (embryo ... pictures of the inside of the body using sound waves. Ultrasound imaging, also called ultrasound scanning or ...

  15. Randomized double-blind clinical trial comparing two anesthetic techniques for ultrasound-guided transvaginal follicular puncture

    PubMed Central

    de Oliveira, Gilvandro Lins; Serralheiro, Fernando Cesar; Fonseca, Fernando Luiz Affonso; Ribeiro, Onésimo Duarte; Adami, Fernando; Christofolini, Denise Maria; Bianco, Bianca; Barbosa, Caio Parente

    2016-01-01

    ABSTRACT Objective: To compare the anesthetic techniques using propofol and fentanyl versus midazolam and remifentanil associated with a paracervical block with lidocaine in performing ultrasound-guided transvaginal oocyte aspiration. Methods: A randomized double-blind clinical trial (#RBR-8kqqxh) performed in 61 women submitted to assisted reproductive treatment. The patients were divided into two groups: anesthetic induction with 1mcg/kg of fentanyl associated with 1.5mg/kg of propofol (FP Group, n=32), in comparison with anesthetic induction using 0.075mg/kg of midazolam associated with 0.25mcg/kg/min of remifentanil, and paracervical block with 3mL of 2% lidocaine (MRPB Group, n=29). Main outcome measures: human reproduction outcomes, modified Aldrete-Kroulik index, hemodynamic parameters, and salivary cortisol. Results: The results revealed a higher number of embryos formed in the FP Group (p50=2 versus 1; p=0.025), gestation rate two times higher in the FP Group (44.4% versus 22.2%; p=0.127), less time to reach AK=10 in the MRPB Group (p50=10 versus 2; p<0.001), and lower mean of hemodynamic parameters in the MRPB Group (p<0.05). Conclusion: Anesthesia with fentanyl and propofol as well as with midazolam, remifentanil, and paracervical block offered satisfactory anesthetic conditions when performing assisted reproduction procedures, providing comfort for the patient and physician. PMID:27759816

  16. Degradation of aromatic amines in textile-dyeing sludge by combining the ultrasound technique with potassium permanganate treatment.

    PubMed

    Liang, Jieying; Ning, Xun-An; An, Taicheng; Sun, Jian; Zhang, Yaping; Wang, Yujie

    2016-08-15

    This paper reports, for the first time, a combined technique of ultrasound (US) with KMnO4 degradation of aromatic amines in a textile-dyeing sludge. The reaction mechanisms and the degradation kinetics of aromatic amines at various operating parameters (KMnO4 dosage, US power density and pH) were systematically examined by the combined system of US-KMnO4. The results indicated that there was a synergistic effect between US and KMnO4, as US greatly enhanced KMnO4 in the degradation of aromatic amines and exhibited apparent sludge disintegration and separated pollutants from the sludge. In addition to accelerating the Mn(VII) reaction with pollutants in the filtrate, US also caused Mn(VII) to enter the porous sludge and sufficiently facilitated the reaction of the strongly absorbed aromatic amines. The combined treatment of US-KMnO4 was effective in the degradation of aromatic amines in textile-dyeing sludge. On average, 58.7% of monocyclic anilines, 88.3% of other forms of aromatic amines, and 24.0% of TOC were removed under the optimal operating conditions of a KMnO4 dosage of 12mM, an US power density of 1.80W/cm(3) and pH 5. The present study proposed US-KMnO4 treatment as a practical method for the disposal of aromatic amines in textile-dyeing sludge.

  17. Evaluation of modern camera calibration techniques for conventional diagnostic X-ray imaging settings.

    PubMed

    Albiol, Francisco; Corbi, Alberto; Albiol, Alberto

    2017-03-01

    We explore three different alternatives for obtaining intrinsic and extrinsic parameters in conventional diagnostic X-ray frameworks: the direct linear transform (DLT), the Zhang method, and the Tsai approach. We analyze and describe the computational, operational, and mathematical background differences for these algorithms when they are applied to ordinary radiograph acquisition. For our study, we developed an initial 3D calibration frame with tin cross-shaped fiducials at specific locations. The three studied methods enable the derivation of projection matrices from 3D to 2D point correlations. We propose a set of metrics to compare the efficiency of each technique. One of these metrics consists of the calculation of the detector pixel density, which can be also included as part of the quality control sequence in general X-ray settings. The results show a clear superiority of the DLT approach, both in accuracy and operational suitability. We paid special attention to the Zhang calibration method. Although this technique has been extensively implemented in the field of computer vision, it has rarely been tested in depth in common radiograph production scenarios. Zhang's approach can operate on much simpler and more affordable 2D calibration frames, which were also tested in our research. We experimentally confirm that even three or four plane-image correspondences achieve accurate focal lengths.

  18. Adhesion, friction, wear, and lubrication research by modern surface science techniques.

    NASA Technical Reports Server (NTRS)

    Keller, D. V., Jr.

    1972-01-01

    The field of surface science has undergone intense revitalization with the introduction of low-energy electron diffraction, Auger electron spectroscopy, ellipsometry, and other surface analytical techniques which have been sophisticated within the last decade. These developments have permitted submono- and monolayer structure analysis as well as chemical identification and quantitative analysis. The application of a number of these techniques to the solution of problems in the fields of friction, lubrication, and wear are examined in detail for the particular case of iron; and in general to illustrate how the accumulation of pure data will contribute toward the establishment of physiochemical concepts which are required to understand the mechanisms that are operational in friction systems. In the case of iron, LEED, Auger and microcontact studies have established that hydrogen and light-saturated organic vapors do not establish interfaces which prevent iron from welding, whereas oxygen and some oxygen and sulfur compounds do reduce welding as well as the coefficient of friction. Interpretation of these data suggests a mechanism of sulfur interaction in lubricating systems.

  19. Magnetic Resonance and Ultrasound Image Fusion Supported Transperineal Prostate Biopsy Using the Ginsburg Protocol: Technique, Learning Points, and Biopsy Results.

    PubMed

    Hansen, Nienke; Patruno, Giulio; Wadhwa, Karan; Gaziev, Gabriele; Miano, Roberto; Barrett, Tristan; Gnanapragasam, Vincent; Doble, Andrew; Warren, Anne; Bratt, Ola; Kastner, Christof

    2016-08-01

    high, prostate biopsies may not be needed for all men with elevated prostate-specific antigen values and nonsuspicious mpMRI. We present our technique to sample (biopsy) the prostate by the transperineal route (the area between the scrotum and the anus) to detect prostate cancer using a fusion of magnetic resonance and ultrasound images to guide the sampling. Copyright © 2016 European Association of Urology. All rights reserved.

  20. Noninvasive Diagnosis of Nonalcoholic Fatty Liver Disease and Quantification of Liver Fat Using a New Quantitative Ultrasound Technique

    PubMed Central

    Lin, Steven C.; Heba, Elhamy; Wolfson, Tanya; Ang, Brandon; Gamst, Anthony; Han, Aiguo; Erdman, John W.; O’Brien, William D.; Andre, Michael P.; Sirlin, Claude B.; Loomba, Rohit

    2014-01-01

    Background & Aims Liver biopsy analysis is the standard method used to diagnose nonalcoholic fatty liver disease (NAFLD). Advanced magnetic resonance imaging is a noninvasive procedure that can accurately diagnose and quantify steatosis, but is expensive. Conventional ultrasound is more accessible but identifies steatosis with low levels of sensitivity, specificity, and quantitative accuracy, and results vary among operators. A new quantitative ultrasound (QUS) technique can identify steatosis in animal models. We assessed the accuracy of QUS in the diagnosis and quantification hepatic steatosis, comparing findings with those from MRI proton density fat fraction (MRI-PDFF) analysis as a reference. Methods We performed a prospective, cross-sectional analysis of a cohort of adults (n=204) with NAFLD (MRI-PDFF≥5%) and without NAFLD (controls). Subjects underwent MRI-PDFF and QUS analyses of the liver on the same day at the University of California, San Diego, from February 2012 through March 2014. QUS parameters and backscatter coefficient (BSC) values were calculated. Patients were randomly assigned to training (n=102; mean age, 51±17 years; mean body mass index, 31±7 kg/m2) and validation (n=102; mean age, 49±17 years; body mass index, 30±6 kg/m2) groups; 69% of patients in each group had NAFLD. Results BSC (range 0.00005–0.25 1/cm-sr) correlated with MRI-PDFF (Spearman’s ρ=0.80; P<.0001). In the training group, the BSC analysis identified patients with NAFLD with an area under the curve value of 0.98 (95% confidence interval, 0.95–1.00; P<.0001). The optimal BSC cutoff value identified patients with NAFLD in the training and validation groups with 93% and 87% sensitivity, 97% and 91% specificity, 86% and 76% negative predictive values, and 99% and 95% positive predictive values, respectively. Conclusions QUS measurements of BSC can accurately diagnose and quantify hepatic steatosis, based on a cross-sectional analysis that used MRI-PDFF as the

  1. Ultrasound of tibialis anterior muscle and tendon: anatomy, technique of examination, normal and pathologic appearance.

    PubMed

    Varghese, Ajay; Bianchi, Stefano

    2014-06-01

    Lesions of the tibialis anterior muscle and tendon are not frequently reported in international literature although pathology is not rare. Pathology can be spontaneous, associated with arthropathy or more generalized conditions. Clinical assessment may not be sufficient for distinguishing conditions like tendinopathy, tears, bursitis, etc. Therefore, imaging studies are necessary to plan appropriate therapy. US has a number of advantages, including widespread availability, absence of contraindications and low cost. It can also be used for dynamic studies of the muscle during contraction and relaxation. This article reviews the anatomy of the tibialis anterior, normal variants, the technique used for standard US examination of this muscle and tendon, its normal appearance on US and the sonographic characteristics of the most common lesions that affect it including tips on US-guided injections used for treatment.

  2. Ultrasound-Guided Quadratus Lumborum Block: An Updated Review of Anatomy and Techniques.

    PubMed

    Ueshima, Hironobu; Otake, Hiroshi; Lin, Jui-An

    2017-01-01

    Purpose of Review. Since the original publication on the quadratus lumborum (QL) block, the technique has evolved significantly during the last decade. This review highlights recent advances in various approaches for administering the QL block and proposes directions for future research. Recent Findings. The QL block findings continue to become clearer. We now understand that the QL block has several approach methods (anterior, lateral, posterior, and intramuscular) and the spread of local anesthetic varies with each approach. In particular, dye injected using the anterior QL block approach spread to the L1, L2, and L3 nerve roots and within psoas major and QL muscles. Summary. The QL block is an effective analgesic tool for abdominal surgery. However, the best approach is yet to be determined. Therefore, the anesthetic spread of the several QL blocks must be made clear.

  3. Ultrasound-Guided Quadratus Lumborum Block: An Updated Review of Anatomy and Techniques

    PubMed Central

    Otake, Hiroshi

    2017-01-01

    Purpose of Review. Since the original publication on the quadratus lumborum (QL) block, the technique has evolved significantly during the last decade. This review highlights recent advances in various approaches for administering the QL block and proposes directions for future research. Recent Findings. The QL block findings continue to become clearer. We now understand that the QL block has several approach methods (anterior, lateral, posterior, and intramuscular) and the spread of local anesthetic varies with each approach. In particular, dye injected using the anterior QL block approach spread to the L1, L2, and L3 nerve roots and within psoas major and QL muscles. Summary. The QL block is an effective analgesic tool for abdominal surgery. However, the best approach is yet to be determined. Therefore, the anesthetic spread of the several QL blocks must be made clear. PMID:28154824

  4. Testing the applicability of six macroscopic skeletal aging techniques on a modern Southeast Asian sample.

    PubMed

    Gocha, Timothy P; Ingvoldstad, Megan E; Kolatorowicz, Adam; Cosgriff-Hernandez, Meghan-Tomasita J; Sciulli, Paul W

    2015-04-01

    Most macroscopic skeletal aging techniques used by forensic anthropologists have been developed and tested only on reference material from western populations. This study examined the performance of six aging techniques on a known age sample of 88 Southeast Asian individuals. Methods examined included the Suchey-Brooks method of aging the symphyseal face of the os pubis (Brooks and Suchey, Hum. Evol. 5 (1990) 227), Buckberry and Chamberlain's, Am. J. Phys. Anthropol. 119 (2002) 231 and Osborne et al.'s, J. Forensic Sci. 49 (2004) 1 revisions of the Lovejoy et al., Am. J. Phys. Anthropol. 68 (1985) 15 method of aging the auricular surface of the ilium, İşcan et al.'s, J. Forensic Sci. 29 (1984) 1094, İşcan et al.'s, J. Forensic Sci. 30 (1985) 853 method of aging the sternal end of the fourth rib, and Meindl and Lovejoy's, Am. J. Phys. Anthropol. 68 (1985) 57 methods for aging both lateral-anterior and vault sutures on the cranium. The results of this study indicate that application of aging techniques commonly used in forensic anthropology to individuals identified as Asian, and more specifically Southeast Asian, should not be undertaken injudiciously. Of the six individual methods tested here, the Suchey-Brooks pubic symphysis aging method performs best, though average age estimates were still off by nearly 10 years or greater. Methods for aging the auricular surface perform next best, though the Osborne et al. method works better for individuals below 50 years and the Buckberry and Chamberlain method works better for those above 50 years. Methods for age estimation from the sternal ends of the fourth rib and vault and lateral-anterior cranial sutures perform poorly and are not recommended for use on remains of Southeast Asian ancestry. Combining age estimates from multiple indicators, specifically the pubic symphysis and one auricular surface method, was superior to individual methods. Data and a worked example are provided for calculating the conditional

  5. A technique for ultrasound-guided blood sampling from a dry and gel-free puncture area.

    PubMed

    Thorn, Sofie; Gopalasingam, Nigopan; Bendtsen, Thomas Fichtner; Knudsen, Lars; Sloth, Erik

    2016-05-07

    Vein punctures are performed daily to sample blood. Ultrasound (US) offers an alternative to the blind landmark technique for difficult vascular access. A challenge for this procedure is the presence of US gel in the puncture area. We present a technique for US-guided puncture from extremity veins not palpable or visible to the human eye, while keeping the puncture area dry and gel-free. Ten healthy volunteers underwent two US-guided vein punctures from veins that were neither palpable nor visible. One was drawn from an antebrachial vein and another from a brachial vein. A sterile barrier drape was made from a commercially available dressing and a piece of transparent sterile plastic. The barrier drape consists of an adhesive part placed on the skin designed for sonography and a free transparent flap constituting the barrier between the unsterile sonographic site and the sterile gel-free puncture site. The success rate for vein puncture was 100% in both locations. A total of 22 skin punctures were performed (11 antebrachial and 11 brachial). Gain output was increased 7% (4-12%), and 8% (4-15%), respectively, to compensate for attenuation of the US signal due to the drape. Alignment of the centre of the transducer with the long-axis of the target vein during the procedure was reported as a challenge. US-guided blood sampling from a brachial and antebrachial vein was possible with a 100% success rate, while ensuring a dry and gel-free venipuncture area on one side and the transducer on the other side of a sterile barrier.

  6. Ultrasound melted polymer sleeve for improved screw anchorage in trabecular bone--A novel screw augmentation technique.

    PubMed

    Schmoelz, W; Mayr, R; Schlottig, F; Ivanovic, N; Hörmann, R; Goldhahn, J

    2016-03-01

    Screw anchorage in osteoporotic bone is still limited and makes treatment of osteoporotic fractures challenging for surgeons. Conventional screws fail in poor bone quality due to loosening at the screw-bone interface. A new technology should help to improve this interface. In a novel constant amelioration process technique, a polymer sleeve is melted by ultrasound in the predrilled screw hole prior to screw insertion. The purpose of this study was to investigate in vitro the effect of the constant amelioration process platform technology on primary screw anchorage. Fresh frozen femoral heads (n=6) and vertebrae (n=6) were used to measure the maximum screw insertion torque of reference and constant amelioration process augmented screws. Specimens were cut in cranio-caudal direction, and the screws (reference and constant amelioration process) were implanted in predrilled holes in the trabecular structure on both sides of the cross section. This allowed the pairwise comparison of insertion torque for constant amelioration process and reference screws (femoral heads n=18, vertebrae n=12). Prior to screw insertion, a micro-CT scan was made to ensure comparable bone quality at the screw placement location. The mean insertion torque for the constant amelioration process augmented screws in both, the femoral heads (44.2 Ncm, SD 14.7) and the vertebral bodies (13.5 Ncm, SD 6.3) was significantly higher than for the reference screws of the femoral heads (31.7 Ncm, SD 9.6, p<0.001) and the vertebral bodies (7.1 Ncm, SD 4.5, p<0.001). The interconnection of the melted polymer sleeve with the surrounding trabecular bone in the constant amelioration process technique resulted in a higher screw insertion torque and can improve screw anchorage in osteoporotic trabecular bone. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Biogeosystem technique - the fundamental base of modern Water Policy and Management

    NASA Astrophysics Data System (ADS)

    Kalinitchenko, Valery; Batukaev, Abdulmalik; Minkina, Tatiana; Solntseva, Natalia; Skovpen, Andrey; Zarmaev, Ali; Jusupov, Vaha; Lohmanova, Olga

    2014-05-01

    out from active biosphere stage to vadose zone. These substances are entering the undesired stage of sedimentation and lithogenesis. Such adverse events are enhanced by irrigation. As a result, up to 80-90% of the fresh water taken for irrigation from lakes, rivers, storage reservoirs, desalinators are lost useless entailing economic losses. As a result of irrigation the quality of water is deteriorated as well as the quality of soil and landscape. A quality of human environment and a quality of biosphere as a whole is reduced. It is much more dangerous than economic losses. The irrigation paradigm shift is essential for successful water policy and water management in modern world. In a framework of Biogeosystem technics the new intrasoil pulse continuous-discrete paradigm of irrigation is developed. Water is supplied by small discrete portions into individual volumes of a soil continuum without excess soil mass transfer, transpiration, evaporation and seepage. New paradigm of irrigation optimizes plant growth, reduces consumption of water per unit of biological product, the yield increases. It provides the soil and landscape conservation, fresh water - the global deficit - saving up to 10-20 times, biological productivity and sustainability of biosphere. Intrasoil pulse continuous-discrete robotic irrigation technologies match the nowadays noosphere technological platform.

  8. Three dimensional ultrasound and hdlive technology as possible tools in teaching embryology.

    PubMed

    Popovici, Razvan; Pristavu, Anda; Sava, Anca

    2017-10-01

    Embryology is an important subject in order to gain an understanding of medicine and surgery; however, sometimes students find the subject difficult to grasp and apply to clinical practice. Modern imaging techniques can be useful aids in teaching and understanding embryology. Imaging techniques have very rapidly evolved over the last few years, advancing from two- to three-dimensional (3D) ultrasound. HDlive is an innovative ultrasound technique that generates near-realistic images of the human fetus. In order to evince the capabilities of 3D ultrasound and HDlive technology in teaching embryology, we evaluated using this technique the normal evolution of the embryo and fetus from the fifth to eleventh week of amenorrhea. Our conclusion is that by yielding clear and impressive images, 3D ultrasound and HDlive could be useful tools in teaching embryology to medical students. Clin. Anat. 30:953-957, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  9. Outcomes of Bankart Repairs Using Modern Arthroscopic Technique in an Athletic Population.

    PubMed

    Milchteim, Charles; Tucker, Scott A; Nye, Darin D; Lamour, Richard J; Liu, Wei; Andrews, James R; Ostrander, Roger V

    2016-07-01

    To report a large number of highly active patients who underwent arthroscopic Bankart repair at our institution over the last decade. A retrospective analysis of patients who underwent primary and revision arthroscopic Bankart repairs using bioabsorbable anchors was performed. Outcome measures included recurrence of dislocation, American Shoulder and Elbow Scores (ASES), Rowe, visual analog scale (VAS), return to sports, and satisfaction scores. A total of 94 shoulders met the inclusion criteria. The recurrence rate was 6/94 (6.4%) at a mean follow-up of 5 years (range, 3 to 8.3). The mean postoperative scores were as follows: ASES = 91.5/100; Rowe = 84.3/100; VAS = 0.8/10; satisfaction = 8.8/10. In those who attempted to return to sports, 82.5% were able to return to the same level of competition. Statistical analyses revealed a significant increase in risk of recurrence among high school and recreational athletes. No recurrences were observed among professional or college-level athletes. No significant difference in recurrence rates was observed in regards to age, time to surgery, type of athlete (collision v limited contact), repair of SLAP lesion, number of anchors, or revision surgery. Although several repair techniques exist for traumatic anterior shoulder instability, arthroscopic repair remains a viable option even in a highly active patient population. This study uniquely identified high school and recreational athletes at higher risk for recurrence. This is perhaps due to inferior shoulder development and technique as well as to limited access to postoperative physical therapy. Level IV, therapeutic case series. Copyright © 2016 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  10. Portable ultrasound in disaster triage: a focused review.

    PubMed

    Wydo, S M; Seamon, M J; Melanson, S W; Thomas, P; Bahner, D P; Stawicki, S P

    2016-04-01

    Ultrasound technology has become ubiquitous in modern medicine. Its applications span the assessment of life-threatening trauma or hemodynamic conditions, to elective procedures such as image-guided peripheral nerve blocks. Sonographers have utilized ultrasound techniques in the pre-hospital setting, emergency departments, operating rooms, intensive care units, outpatient clinics, as well as during mass casualty and disaster management. Currently available ultrasound devices are more affordable, portable, and feature user-friendly interfaces, making them well suited for use in the demanding situation of a mass casualty incident (MCI) or disaster triage. We have reviewed the existing literature regarding the application of sonology in MCI and disaster scenarios, focusing on the most promising and practical ultrasound-based paradigms applicable in these settings.

  11. Body composition in sport: a comparison of a novel ultrasound imaging technique to measure subcutaneous fat tissue compared with skinfold measurement.

    PubMed

    Müller, Wolfram; Horn, Martin; Fürhapter-Rieger, Alfred; Kainz, Philipp; Kröpfl, Julia M; Maughan, Ronald J; Ahammer, Helmut

    2013-11-01

    Extremely low weight and rapid changes in weight and body composition have become major concerns in many sports, but sufficiently accurate field methods for body composition assessment in athletes are missing. This study aimed to explore the use of ultrasound methods for assessment of body fat content in athletes. 19 female athletes (stature: 1.67(± 0.06) m, weight: 59.6(± 7.6) kg; age: 19.5(± 3.3) years) were investigated by three observers using a novel ultrasound method for thickness measurement of uncompressed subcutaneous adipose tissue and of embedded structures. Two observers also measured skinfold thickness at eight International Society for the Advancement of Kinanthrometry (ISAK) sites; mean skinfold values were compared to mean subcutaneous adipose tissue thicknesses measured by ultrasound. Interobserver reliability of imaging and evaluation obtained by this ultrasound technique: intraclass correlation coefficient ICC=0.968 (95% CI 0.957 to 0.977); evaluation of given images: ICC=0.997 (0.993 to 0.999). Skinfold compared to ultrasound thickness showed that compressibility of subcutaneous adipose tissue depends largely on the site and the person: regression slopes ranged from 0.61 (biceps) to 1.59 (thigh) and CIs were large. Limits of agreement ranged from 2.6 to 8.6 mm. Regression lines did not intercept the skinfold axis at zero because of the skin thickness being included in the skinfold. The four ISAK trunk sites caused ultrasound imaging problems in 13 of 152 sites (8 ISAK sites, 19 athletes). The ultrasound method allows measurement of uncompressed subcutaneous adipose tissue thickness with an accuracy of 0.1-0.5 mm, depending on the probe frequency. Compressibility of the skinfold depends on the anatomical site, and skin thickness varies by a factor of two. This inevitably limits the skinfold methods for body fat estimation. Ultrasound accuracy for subcutaneous adipose tissue measurement is limited by the plasticity of fat and furrowed tissue

  12. Validation of a technique using microbubbles and contrast enhanced ultrasound (CEUS) to biopsy sentinel lymph nodes (SLN) in pre-operative breast cancer patients with a normal grey-scale axillary ultrasound.

    PubMed

    Cox, K; Sever, A; Jones, S; Weeks, J; Mills, P; Devalia, H; Fish, D; Jones, P

    2013-07-01

    In patients with breast cancer, grey-scale ultrasound often fails to identify lymph node (LN) metastases. We aimed to validate the technique of contrast-enhanced ultrasound (CEUS) as a test to identify sentinel lymph node (SLN) metastases and reduce the numbers of patients requiring a completion axillary node clearance (ANC). 371 patients with breast cancer and a normal axillary ultrasound were recruited. Patients received periareolar intra-dermal injection of microbubble contrast agent. Breast lymphatics were visualised by CEUS and followed to identify and biopsy axillary SLN. Patients then underwent standard tumour excision and either SLN excision (benign biopsy) or axillary clearance (malignant biopsy) with subsequent histopathological analysis. The technique failed in 46 patients, 6 patients had indeterminate biopsy results and 24 patients were excluded. In 295 patients with a conclusive SLN biopsy, the sensitivity of the technique was 61% and specificity 100%. Given a benign SLN biopsy result, the post-test probability that a patient had SLN metastases was 8%. 35 patients were found to have SLN metastases and had a primary ANC (29 macrometastases and 6 micrometastases/ITC). There were 22 false negative results (10 macrometastases and 12 micrometastases). Macrometastases in core biopsy specimens correlated with LN macrometastases on surgical excision. Pre-operative biopsy of SLN reduced the numbers of patients requiring completion ANC. Despite the low sensitivity, only 22 patients (8%) with a benign SLN biopsy were subsequently found to have LN metastases. Without the confirmation of macrometastases on core biopsy specimens, patients with micrometastases/ITC may be inadvertently selected for primary ANC. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Real-time ultrasound-guided catheterisation of the internal jugular vein: a prospective comparison with the landmark technique in critical care patients

    PubMed Central

    Karakitsos, Dimitrios; Labropoulos, Nicolaos; De Groot, Eric; Patrianakos, Alexandros P; Kouraklis, Gregorios; Poularas, John; Samonis, George; Tsoutsos, Dimosthenis A; Konstadoulakis, Manousos M; Karabinis, Andreas

    2006-01-01

    Introduction Central venous cannulation is crucial in the management of the critical care patient. This study was designed to evaluate whether real-time ultrasound-guided cannulation of the internal jugular vein is superior to the standard landmark method. Methods In this randomised study, 450 critical care patients who underwent real-time ultrasound-guided cannulation of the internal jugular vein were prospectively compared with 450 critical care patients in whom the landmark technique was used. Randomisation was performed by means of a computer-generated random-numbers table, and patients were stratified with regard to age, gender, and body mass index. Results There were no significant differences in gender, age, body mass index, or side of cannulation (left or right) or in the presence of risk factors for difficult venous cannulation such as prior catheterisation, limited sites for access attempts, previous difficulties during catheterisation, previous mechanical complication, known vascular abnormality, untreated coagulopathy, skeletal deformity, and cannulation during cardiac arrest between the two groups of patients. Furthermore, the physicians who performed the procedures had comparable experience in the placement of central venous catheters (p = non-significant). Cannulation of the internal jugular vein was achieved in all patients by using ultrasound and in 425 of the patients (94.4%) by using the landmark technique (p < 0.001). Average access time (skin to vein) and number of attempts were significantly reduced in the ultrasound group of patients compared with the landmark group (p < 0.001). In the landmark group, puncture of the carotid artery occurred in 10.6% of patients, haematoma in 8.4%, haemothorax in 1.7%, pneumothorax in 2.4%, and central venous catheter-associated blood stream infection in 16%, which were all significantly increased compared with the ultrasound group (p < 0.001). Conclusion The present data suggest that ultrasound

  14. Postprostatectomy ultrasound-guided transrectal implantation of gold markers for external beam radiotherapy. Technique and complications rate.

    PubMed

    Langenhuijsen, J F; Donker, R; McColl, G M; Kiemeney, L A L M; Witjes, J A; van Lin, E N J T

    2013-06-01

    Postprostatectomy radiotherapy (RT) improves survival in adjuvant and salvage settings. The implantation technique and complications rate of gold markers in the prostate bed for high-precision RT were analyzed. Patients undergoing postprostatectomy RT for prostate-specific antigen (PSA) relapse or high-risk disease were enrolled in the study. Under transrectal ultrasound guidance, three fine gold markers were implanted in the prostate bed and the technical difficulties of insertion were documented. Patients received our self-designed questionnaires concerning complications and pain. The influence of anticoagulants and coumarins on bleeding was analyzed, as was the effect of potential risk factors on pain. In 77 consecutive patients, failure of marker implantation or marker migration was seen in six cases. Rectal bleeding was reported by 10 patients and 1 had voiding complaints. No macroscopic hematuria persisting for more than 3 days was observed. Other complications included rectal discomfort (n = 2), nausea (n = 1), abdominal discomfort (n = 1), and pain requiring analgesics (n = 4). No major complications were reported. On a 0-10 visual analogue scale (VAS), the mean pain score was 3.7. No clinically significant risk factors for complications were identified. Transrectal implantation of gold markers in the prostate bed is feasible and safe. Alternatives like cone beam computed tomography (CBCT) should be considered, but the advantages of gold marker implantation for high-precision postprostatectomy RT would seem to outweigh the minor risks involved.

  15. A clinical study of thermal monitoring techniques of ultrasound-guided microwave ablation for hepatocellular carcinoma in high-risk locations

    PubMed Central

    Zhi-yu, Han; Ping, Liang; Xiao-ling, Yu; Zhi-gang, Cheng; Fang-yi, Liu; Jie, Yu

    2017-01-01

    To confirm the safety and effectiveness of the minimally invasive thermal monitor technique on percutaneous ultrasound-guided microwave ablation (MWA) for hepatocellular carcinoma (HCC) in high-risk locations, a total of 189 patients with 226 HCC nodules in high-risk locations were treated with MWA. The real-time temperature of the tissue between the lesion margin and the vital structures was monitored by inserting a 21G thermal monitoring needle. The major indexes of technical success, technique effectiveness, local tumour progression and complications were observed during the follow-up period. Technical success was acquired in all patients. Technique effectiveness was achieved with one session in 119 lesions based on contrast-enhanced ultrasound (CEUS) 3–5 days after treatment. An additional 95 lesions achieved technique effectiveness at the second session. Within the follow–up period of 6–58 months (median 38 months), the 1-, 2-, 3-, and 4-year local tumour progression rate was 11.1%, 18.1%, 19.1%, and 19.9%, respectively. There were no major complications in all the patients except for the common side effects. These results indicate that the thermal monitor technique can be applied to prevent major complications in vulnerable structures and allow percutaneous MWA to achieve satisfactory technique effectiveness in the treatment of HCC in high-risk locations. PMID:28112263

  16. Obtaining accurate and precise environmental reconstructions from the modern analog technique and North American surface pollen dataset

    NASA Astrophysics Data System (ADS)

    Williams, J. W.; Shuman, B.

    2008-04-01

    Using a recently compiled surface-sample pollen dataset for North America, we test methods to improve the skillfulness (i.e. accuracy and precision) of the modern analog technique (MAT) for continental- to sub-continental-scale paleoenvironmental reconstructions. Interregional floristic differences challenge such reconstructions, because with widening spatial extent each pollen type represents an increasing number of species, each with its unique niche, thus blurring pollen-climate relationships. We conduct a series of cross-validation experiments in which we first explore (1) whether increasing the spatial extent of the pool of potential analogs improves or worsens MAT skill, (2) whether MAT skill is improved by increasing the number of pollen taxa and splitting pollen taxa into regional groups, and (3) the differences in MAT skill among environmental variables. Regional splits are guided by the range boundaries of parent species. Results are analyzed for multiple environmental variables. We then systematically explore options for (a) the value of the no-analog/analog threshold (T), (b) the maximum number of modern analogs (N) allowed for a target fossil sample, and (c) whether the environmental average constructed from the modern analogs should be weighted by their compositional dissimilarity (D) to the target sample. We demonstrate that substantial interregional differences in pollen-climate relationships, particularly between eastern and western North America, degrade MAT precision and accuracy, but these adverse effects can be overcome by expanding the list of taxa used and/or splitting pollen types into regional groups. MAT precision was best when pollen types were regionally split and better when more taxa were used, although increasing the taxon list from 64 to 135 types did not substantially increase performance. Temperature-related variables were reconstructed more precisely than hydrological variables, and there was little difference in MAT skill between

  17. Percutaneous Ultrasound-Guided TOPAZ Radiofrequency Coblation: A Novel Coaxial Technique for the Treatment of Recalcitrant Plantar Fasciitis-Our Experience.

    PubMed

    Shah, Amit; Best, Alistair J; Rennie, Winston J

    2016-06-01

    Various therapeutic options are available for treatment of recalcitrant plantar fasciitis. Studies using TOPAZ coblation (ArthroCare, Sunnyvale, CA) have had good early results. The current coblation technique involves a surgical incision or breach of the highly specialized plantar fat pad, which can be associated with risks. We describe a novel technique of ultrasound-guided percutaneous coblation with a lateral heel approach. Advantages include precise targeting of the plantar fascia by direct dynamic visualization of the coblation tip, a true percutaneous approach with a needle skin puncture (<5 mm), and preservation of the plantar fat pad by using a lateral heel approach.

  18. Extraction of Natural Antioxidants from the Thelephora ganbajun Mushroom by an Ultrasound-Assisted Extraction Technique and Evaluation of Antiproliferative Activity of the Extract against Human Cancer Cells.

    PubMed

    Xu, Dong-Ping; Zheng, Jie; Zhou, Yue; Li, Ya; Li, Sha; Li, Hua-Bin

    2016-10-01

    The Thelephora ganbajun mushroom has been found to be a potential rich source of natural antioxidants. In this study, an ultrasound-assisted extraction (UAE) technique together with GRAS (generally recognized as safe) solvents (ethanol and water) was used to maximize the extraction of antioxidants from Thelephora ganbajun. Five extraction parameters (ethanol concentration, solvent to solid ratio, extraction time, temperature and ultrasound power) were investigated by single-factor experiments, and then a central composite rotatable design was employed to study interaction of three key extraction parameters. The optimum conditions were as follows: 57.38% ethanol, 70.15 mL/g solvent to solid ratio, 10.58 min extraction time, 40 °C extraction temperature and 500 W ultrasound power. Under the optimum conditions, the antioxidant activity obtained was 346.98 ± 12.19 µmol Trolox/g DW, in accordance with the predicted value of 344.67 µmol Trolox/g DW. Comparison of UAE with conventional maceration and Soxhlet extraction, the UAE method showed stronger extract efficiency in a shorter extraction time. These results showed that UAE was an effective technique to extract antioxidants from Thelephora ganbajun. Furthermore, the extracts obtained under the optimized conditions exhibited antiproliferative activities toward human lung (A549), breast (MCF-7), liver (HepG2) and colon (HT-29) cancer cells, especially for liver and lung cancer cells. In addition, rutin, 2-hydrocinnamic acid and epicatechin were identified in the extract, which might contribute to antioxidant and antiproliferative activities.

  19. Applications of ultrasound in food technology: Processing, preservation and extraction.

    PubMed

    Chemat, Farid; Zill-e-Huma; Khan, Muhammed Kamran

    2011-07-01

    Ultrasound is well known to have a significant effect on the rate of various processes in the food industry. Using ultrasound, full reproducible food processes can now be completed in seconds or minutes with high reproducibility, reducing the processing cost, simplifying manipulation and work-up, giving higher purity of the final product, eliminating post-treatment of waste water and consuming only a fraction of the time and energy normally needed for conventional processes. Several processes such as freezing, cutting, drying, tempering, bleaching, sterilization, and extraction have been applied efficiently in the food industry. The advantages of using ultrasound for food processing, includes: more effective mixing and micro-mixing, faster energy and mass transfer, reduced thermal and concentration gradients, reduced temperature, selective extraction, reduced equipment size, faster response to process extraction control, faster start-up, increased production, and elimination of process steps. Food processes performed under the action of ultrasound are believed to be affected in part by cavitation phenomena and mass transfer enhancement. This review presents a complete picture of current knowledge on application of ultrasound in food technology including processing, preservation and extraction. It provides the necessary theoretical background and some details about ultrasound the technology, the technique, and safety precautions. We will also discuss some of the factors which make the combination of food processing and ultrasound one of the most promising research areas in the field of modern food engineering.

  20. Ultrasound in anesthesia: applying scientific principles to clinical practice.

    PubMed

    Falyar, Christian R

    2010-08-01

    The use of ultrasound as an adjunct to invasive anesthesia procedures is becoming commonplace. The U.S. Agency for Health Care Quality and the United Kingdom National Institute for Clinical Excellence have identified the role of ultrasound in improving patient safety. Numerous studies have demonstrated the benefits of ultrasound, yet there have also been articles inferring it may not offer additional benefits to traditional landmark techniques. The major disadvantage often cited is that success is user-dependent, and using ultrasound is a unique skill that requires training and experience to become proficient. Modern ultrasound systems incorporate 2 sound technologies to provide users with specific information about what is being viewed. Brightness mode imaging and pulsed-wave Doppler can be combined to reduce potential complications associated with central venous access and regional anesthesia. Human tissue is also an important factor in ultrasound imaging. The different densities of soft tissues, bone, fluid, and air all interact with sound, creating distinctive images that can aid and potentially hinder accuracy. Comprehension of basic ultrasound principles and how it is affected by tissue will enable anesthetists to better understand what is being seen and reduce the potential for errors.

  1. A Temporal View of Soft Tissue Quantitative Ultrasound

    NASA Astrophysics Data System (ADS)

    O'Brien, William D.

    The objective of soft tissue quantitative ultrasound (QUS) is to improve diagnostic ultrasound imaging capabilities via quantitative outcomes. Over the past three or so decades, there have been an increasing number of QUS successes. A temporal view moves us back in history almost six decades when techniques and theoretical developments were in their earliest stages that impacted modern QUS successes. The earliest theoretical developments and techniques some six decades ago can be attributed to Lev Chernov, Philip Morse, Herman Feshbach, Uno Ingard, John Wild and Jack Reid. Later, Floyd Dunn developed important views as to how connective tissue affected the interaction between ultrasound and soft tissue. Then, as the theory of wave propagation in soft tissues with random inhomogeneities was extended and applied by Fred Lizzi, Jim Zagzebski and Mike Insana (and their colleagues), contemporary QUS successes started to emerge.

  2. Intravascular ultrasound imaging

    SciTech Connect

    Cavaye, D.M.; White, R.A. )

    1992-01-01

    This book will give vascular surgeons, cardiologists, radiologists, and technologists a complete working knowledge of intravascular ultrasound imaging and the crucial role of this new technology in endovascular diagnosis and therapy. The book reviews the essential principles of vascular pathology and ultrasound imaging and then provides state-of-the-art information on intraluminal ultrasound imaging devices and techniques, including practical guidelines for using catheters, optimizing image quality, and avoiding artifacts. Image interpretation and computerized image reconstruction are also discussed in detail. The first section explains the diagnostic, therapeutic, and experimental applications of intravascular ultrasound, particularly as a adjunct to angioplasty and other current interventional procedures.

  3. Mutational Spectrum of DMD Mutations in Dystrophinopathy Patients: Application of Modern Diagnostic Techniques to a Large Cohort

    PubMed Central

    Flanigan, Kevin M.; Dunn, Diane; von Niederhausern, Andrew; Soltanzadeh, Payam; Gappmaier, Eduard; Howard, Michael T.; Sampson, Jacinda; Mendell, Jerry; Wall, Cheryl; King, Wendy; Pestronk, Alan; Florence, Julaine; Connolly, Anne; Mathews, Katherine D.; Stephan, Carrie; Laubenthal, Karla; Wong, Brenda; Morehart, Paula; Meyer, Amy; Finkel, Richard; Bonnemann, Carsten G.; Medne, Livija; Day, John W.; Dalton, Joline C.; Margolis, Marcia; Hinton, Veronica; Weiss, Robert B.

    2010-01-01

    Mutations in the DMD gene, encoding the dystrophin protein, are responsible for the dystrophinopathies Duchenne Muscular Dystrophy (DMD), Becker Muscular Dystrophy (BMD), and X-linked Dilated Cardiomyopathy (XLDC). Mutation analysis has traditionally been challenging, due to the large gene size (79 exons over 2.2 Mb of genomic DNA). We report a very large aggregate data set comprised of DMD mutations detected in samples from patients enrolled in the United Dystrophinopathy Project, a multicenter research consortium, and in referral samples submitted for mutation analysis with a diagnosis of dystrophinopathy. We report 1111 mutations in the DMD gene, including 891 mutations with associated phenotypes. These results encompass 506 point mutations (including 294 nonsense mutations) and significantly expand the number of mutations associated with the dystrophinopathies, highlighting the utility of modern diagnostic techniques. Our data supports the uniform hypermutability of CGA>TGA mutations, establishes the frequency of polymorphic muscle (Dp427m) protein isoforms and reveals unique genomic haplotypes associated with `private' mutations. We note that 60% of these patients would be predicted to benefit from skipping of a single DMD exon using antisense oligonucleotide therapy, and 62% would be predicted to benefit from an inclusive multi-exon skipping approach directed toward exons 45 through 55. PMID:19937601

  4. Total Skin Electron Therapy for Cutaneous T-Cell Lymphoma Using a Modern Dual-Field Rotational Technique

    SciTech Connect

    Heumann, Thatcher R.; Esiashvili, Natia; Parker, Sareeta; Switchenko, Jeffrey M.; Dhabbaan, Anees; Goodman, Michael; Lechowicz, Mary Jo; Flowers, Christopher R.; Khan, Mohammad K.

    2015-05-01

    Purpose: To report our experience with rotational total skin electron irradiation (RTSEI) in cutaneous T-cell lymphoma (CTCL), and to examine response by disease stage and race. Methods and Materials: We reviewed our outcomes for 68 CTCL patients who received RTSEI (≥30 Gy) from 2000 to 2013. Primary outcomes were complete clinical response (CCR), recurrence-free survival (RFS), and overall survival (OS). Using log–rank tests and Cox proportional hazards, OS and RFS were compared across tumor stages at time of RTSEI with further racial subgroup analysis. Results: Median age at diagnosis and at time of radiation was 52 and 56 years, respectively. Median follow-up was 5.1 years, 49% were African American, and 49% were female. At time of treatment, 18, 37, and 13 patients were T stage 2, 3, and 4, respectively. At 6 weeks after RTSEI, overall CCR was 82% (88%, 83%, and 69% for T2, T3, and T4, respectively). Median RFS was 11 months for all patients and 14, 10, and 12 months for stage T2, T3, and T4, respectively. Tumor stage was not associated with RFS or CCR. Maintenance therapy after RTSEI was associated with improved RFS in both crude and multivariable analysis, controlling for T stage. Median OS was 76 months (91 and 59 months for T3 and T4, respectively). With the exception of improved OS in African Americans compared with whites at stage T2, race was not associated with CCR, RFS, or OS. Conclusions: These results represent the largest RTSEI clinical outcomes study in the modern era using a dual-field rotational technique. Our observed response rates match or improve upon the standard set by previous outcome studies using conventional TSEI techniques, despite a large percentage of advanced CTCL lesions in our cohort. We found that clinical response after RTSEI did not seem to be affected by T stage or race.

  5. Total skin electron therapy for cutaneous T-cell lymphoma using a modern dual-field rotational technique.

    PubMed

    Heumann, Thatcher R; Esiashvili, Natia; Parker, Sareeta; Switchenko, Jeffrey M; Dhabbaan, Anees; Goodman, Michael; Lechowicz, Mary Jo; Flowers, Christopher R; Khan, Mohammad K

    2015-05-01

    To report our experience with rotational total skin electron irradiation (RTSEI) in cutaneous T-cell lymphoma (CTCL), and to examine response by disease stage and race. We reviewed our outcomes for 68 CTCL patients who received RTSEI (≥ 30 Gy) from 2000 to 2013. Primary outcomes were complete clinical response (CCR), recurrence-free survival (RFS), and overall survival (OS). Using log-rank tests and Cox proportional hazards, OS and RFS were compared across tumor stages at time of RTSEI with further racial subgroup analysis. Median age at diagnosis and at time of radiation was 52 and 56 years, respectively. Median follow-up was 5.1 years, 49% were African American, and 49% were female. At time of treatment, 18, 37, and 13 patients were T stage 2, 3, and 4, respectively. At 6 weeks after RTSEI, overall CCR was 82% (88%, 83%, and 69% for T2, T3, and T4, respectively). Median RFS was 11 months for all patients and 14, 10, and 12 months for stage T2, T3, and T4, respectively. Tumor stage was not associated with RFS or CCR. Maintenance therapy after RTSEI was associated with improved RFS in both crude and multivariable analysis, controlling for T stage. Median OS was 76 months (91 and 59 months for T3 and T4, respectively). With the exception of improved OS in African Americans compared with whites at stage T2, race was not associated with CCR, RFS, or OS. These results represent the largest RTSEI clinical outcomes study in the modern era using a dual-field rotational technique. Our observed response rates match or improve upon the standard set by previous outcome studies using conventional TSEI techniques, despite a large percentage of advanced CTCL lesions in our cohort. We found that clinical response after RTSEI did not seem to be affected by T stage or race. Published by Elsevier Inc.

  6. Total Skin Electron Therapy for Cutaneous T-Cell Lymphoma Using a Modern Dual-Field Rotational Technique

    PubMed Central

    Heumann, Thatcher R.; Esiashvili, Natia; Parker, Sareeta; Switchenko, Jeffrey M.; Dhabbaan, Anees; Goodman, Michael; Lechowicz, Mary Jo; Flowers, Christopher R.; Khan, Mohammad K.

    2016-01-01

    Purpose To report our experience with rotational total skin electron irradiation (RTSEI) in cutaneous T-cell lymphoma (CTCL), and to examine response by disease stage and race. Methods and Materials We reviewed our outcomes for 68 CTCL patients who received RTSEI (≥30 Gy) from 2000 to 2013. Primary outcomes were complete clinical response (CCR), recurrence-free survival (RFS), and overall survival (OS). Using log–rank tests and Cox proportional hazards, OS and RFS were compared across tumor stages at time of RTSEI with further racial subgroup analysis. Results Median age at diagnosis and at time of radiation was 52 and 56 years, respectively. Median follow-up was 5.1 years, 49% were African American, and 49% were female. At time of treatment, 18, 37, and 13 patients were T stage 2, 3, and 4, respectively. At 6 weeks after RTSEI, overall CCR was 82% (88%, 83%, and 69% for T2, T3, and T4, respectively). Median RFS was 11 months for all patients and 14, 10, and 12 months for stage T2, T3, and T4, respectively. Tumor stage was not associated with RFS or CCR. Maintenance therapy after RTSEI was associated with improved RFS in both crude and multivariable analysis, controlling for T stage. Median OS was 76 months (91 and 59 months for T3 and T4, respectively). With the exception of improved OS in African Americans compared with whites at stage T2, race was not associated with CCR, RFS, or OS. Conclusions These results represent the largest RTSEI clinical outcomes study in the modern era using a dual-field rotational technique. Our observed response rates match or improve upon the standard set by previous outcome studies using conventional TSEI techniques, despite a large percentage of advanced CTCL lesions in our cohort. We found that clinical response after RTSEI did not seem to be affected by T stage or race. PMID:25670538

  7. Long-axis view for ultrasound-guided central venous catheter placement via the internal jugular vein

    PubMed Central

    Mahan, Angel F.; McEvoy, Matthew D.; Gravenstein, Nikolaus

    2016-01-01

    Background In modern practice, real-time ultrasound guidance is commonly employed for the placement of internal jugular vein catheters. With a new tool, such as ultrasound, comes the opportunity to refine and further optimize the ultrasound view during jugular vein catheterization. We describe jugular vein access techniques and use the long-axis view as an alternative to the commonly employed short-axis cross-section view for internal jugular vein access and cannulation. Conclusion The long-axis ultrasound-guided internal jugular vein approach for internal jugular vein cannulation is a useful alternative technique that can provide better needle tip and guidewire visualization than the more traditional short-axis ultrasound view. PMID:28913474

  8. Abdominal Ultrasound

    MedlinePlus

    ... waves. Ultrasound imaging, also called ultrasound scanning or sonography , involves the use of a small transducer (probe) and ultrasound gel placed directly on the skin. High-frequency sound waves are transmitted from the ...

  9. Musculoskeletal Ultrasound

    MedlinePlus

    ... waves. Ultrasound imaging, also called ultrasound scanning or sonography , involves the use of a small transducer (probe) and ultrasound gel placed directly on the skin. High-frequency sound waves are transmitted from the ...

  10. Ultrasound - Breast

    MedlinePlus

    ... waves. Ultrasound imaging, also called ultrasound scanning or sonography , involves the use of a small transducer (probe) and ultrasound gel placed directly on the skin. High-frequency sound waves are transmitted from the ...

  11. Hip Ultrasound

    MedlinePlus

    ... waves. Ultrasound imaging, also called ultrasound scanning or sonography , involves the use of a small transducer (probe) and ultrasound gel placed directly on the skin. High-frequency sound waves are transmitted from the ...

  12. Ultrasound - Scrotum

    MedlinePlus

    ... waves. Ultrasound imaging, also called ultrasound scanning or sonography , involves the use of a small transducer (probe) and ultrasound gel placed directly on the skin. High-frequency sound waves are transmitted from the ...

  13. Obstetrical Ultrasound

    MedlinePlus

    ... waves. Ultrasound imaging, also called ultrasound scanning or sonography , involves the use of a small transducer (probe) and ultrasound gel placed directly on the skin. High-frequency sound waves are transmitted from the ...

  14. Duplex ultrasound

    MedlinePlus

    ... duplex ultrasound combines: Traditional ultrasound: This uses sound waves that bounce off blood vessels to create pictures. Doppler ultrasound: This records sound waves reflecting off moving objects, such as blood, to ...

  15. Ultrasound -- Pelvis

    MedlinePlus

    ... waves. Ultrasound imaging, also called ultrasound scanning or sonography , involves the use of a small transducer (probe) and ultrasound gel placed directly on the skin. High-frequency sound waves are transmitted from the ...

  16. Prostate Ultrasound

    MedlinePlus

    ... waves. Ultrasound imaging, also called ultrasound scanning or sonography , involves the use of a small transducer (probe) and ultrasound gel placed directly on the skin. High-frequency sound waves are transmitted from the ...

  17. Accuracy of Liver Fat Quantification With Advanced CT, MRI, and Ultrasound Techniques: Prospective Comparison With MR Spectroscopy

    PubMed Central

    Kramer, Harald; Pickhardt, Perry J.; Kliewer, Mark A.; Hernando, Diego; Chen, Guang-Hong; Zagzebski, James A.; Reeder, Scott B.

    2016-01-01

    OBJECTIVE The purpose of this study was to prospectively evaluate the accuracy of proton-density fat-fraction, single- and dual-energy CT (SECT and DECT), gray-scale ultrasound (US), and US shear-wave elastography (US-SWE) in the quantification of hepatic steatosis with MR spectroscopy (MRS) as the reference standard. SUBJECTS AND METHODS Fifty adults who did not have symptoms (23 men, 27 women; mean age, 57 ± 5 years; body mass index, 27 ± 5) underwent liver imaging with unenhanced SECT, DECT, gray-scale US, US-SWE, proton-density fat-fraction MRI, and MRS for this prospective trial. MRS voxels for the reference standard were colocalized with all other modalities under investigation. For SECT (120 kVp), attenuation values were recorded. For rapid-switching DECT (80/140 kVp), monochromatic images (70–140 keV) and fat density–derived material decomposition images were reconstructed. For proton-density fat fraction MRI, a quantitative chemical shift–encoded method was used. For US, echogenicity was evaluated on a qualitative 0–3 scale. Quantitative US shear-wave velocities were also recorded. Data were analyzed by linear regression for each technique compared with MRS. RESULTS There was excellent correlation between MRS and both proton-density fat-fraction MRI (r2 = 0.992; slope, 0.974; intercept, −0.943) and SECT (r2 = 0.856; slope, −0.559; intercept, 35.418). DECT fat attenuation had moderate correlation with MRS measurements (r2 = 0.423; slope, 0.034; intercept, 8.459). There was good correlation between qualitative US echogenicity and MRS measurements with a weighted kappa value of 0.82. US-SWE velocity did not have reliable correlation with MRS measurements (r2 = 0.004; slope, 0.069; intercept, 6.168). CONCLUSION Quantitative MRI proton-density fat fraction and SECT fat attenuation have excellent linear correlation with MRS measurements and can serve as accurate noninvasive biomarkers for quantifying steatosis. Material decomposition with DECT does

  18. Vascular color Doppler ultrasound for assessing renovascular hypertension: accuracy of the direct technique for assessing the renal arteries.

    PubMed

    Engelhorn, Carlos Alberto; Engelhorn, Ana Luiza; Pullig, Renata

    2004-05-01

    To assess the accuracy of vascular color Doppler ultrasound as compared with digital subtraction arteriography for identifying hemodynamically significant renal artery stenoses. One hundred and thirty-seven renal arteries from 69 adult patients suspected of having renovascular arterial hypertension were prospectively studied with ultrasound. The results obtained were compared in a double-blind manner with those obtained on digital subtraction arteriography, and the following parameters were calculated according to previously defined criteria: sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy. The inconclusive results (7 arteries) were excluded. The comparison of the 2 methods in regard to the 130 remaining arteries showed concordant results for 116 (89.2%) arteries and discordant results for 14 (10.8%) arteries. The sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy of vascular color Doppler ultrasound were, respectively, 95.33%, 88.14%, 89.86%, 94.55%, and 91.94%. A good correlation between the 2 examinations was observed in the evaluation of the hemodynamically significant renal artery stenoses, making vascular color Doppler ultrasound a noninvasive method useful for selecting patients with suspected renovascular hypertension.

  19. Motion tracking in the liver: Validation of a method based on 4D ultrasound using a nonrigid registration technique

    SciTech Connect

    Vijayan, Sinara; Klein, Stefan; Hofstad, Erlend Fagertun; Langø, Thomas; Lindseth, Frank; Ystgaard, Brynjulf

    2014-08-15

    Purpose: Treatments like radiotherapy and focused ultrasound in the abdomen require accurate motion tracking, in order to optimize dosage delivery to the target and minimize damage to critical structures and healthy tissues around the target. 4D ultrasound is a promising modality for motion tracking during such treatments. In this study, the authors evaluate the accuracy of motion tracking in the liver based on deformable registration of 4D ultrasound images. Methods: The offline analysis was performed using a nonrigid registration algorithm that was specifically designed for motion estimation from dynamic imaging data. The method registers the entire 4D image data sequence in a groupwise optimization fashion, thus avoiding a bias toward a specifically chosen reference time point. Three healthy volunteers were scanned over several breathing cycles (12 s) from three different positions and angles on the abdomen; a total of nine 4D scans for the three volunteers. Well-defined anatomic landmarks were manually annotated in all 96 time frames for assessment of the automatic algorithm. The error of the automatic motion estimation method was compared with interobserver variability. The authors also performed experiments to investigate the influence of parameters defining the deformation field flexibility and evaluated how well the method performed with a lower temporal resolution in order to establish the minimum frame rate required for accurate motion estimation. Results: The registration method estimated liver motion with an error of 1 mm (75% percentile over all datasets), which was lower than the interobserver variability of 1.4 mm. The results were only slightly dependent on the degrees of freedom of the deformation model. The registration error increased to 2.8 mm with an eight times lower temporal resolution. Conclusions: The authors conclude that the methodology was able to accurately track the motion of the liver in the 4D ultrasound data. The authors believe

  20. Pain related to robotic cholecystectomy with lower abdominal ports: effect of the bilateral ultrasound-guided split injection technique of rectus sheath block in female patients

    PubMed Central

    Kim, Jin Soo; Choi, Jong Bum; Lee, Sook Young; Kim, Wook Hwan; Baek, Nam Hyun; Kim, Jayoun; Park, Chu Kyung; Lee, Yeon Ju; Park, Sung Yong

    2016-01-01

    Abstract Background: Robotic cholecystectomy (RC) using port sites in the lower abdominal area (T12-L1) rather than the upper abdomen has recently been introduced as an alternative procedure for laparoscopic cholecystectomy. Therefore, we investigated the time course of different components of pain and the analgesic effect of the bilateral ultrasound-guided split injection technique for rectus sheath block (sRSB) after RC in female patients. Methods: We randomly assigned 40 patients to undergo ultrasound-guided sRSB (RSB group, n = 20) or to not undergo any block (control group, n = 20). Pain was subdivided into 3 components: superficial wound pain, deep abdominal pain, and referred shoulder pain, which were evaluated with a numeric rating scale (from 0 to 10) at baseline (time of awakening) and at 1, 6, 9, and 24 hours postoperatively. Consumption of fentanyl and general satisfaction were also evaluated 1 hour (before discharge from the postanesthesia care unit) and 24 hours postoperatively (end of study). Results: Superficial wound pain was predominant only at awakening, and after postoperative 1 hour in the control group. Bilateral ultrasound-guided sRSB significantly decreased superficial pain after RC (P < 0.01) and resulted in a better satisfaction score (P < 0.05) 1 hour after RC in the RSB group compared with the control group. The cumulative postoperative consumption of fentanyl at 6, 9, and 24 hours was not significantly different between groups. Conclusions: After RC with lower abdominal ports, superficial wound pain predominates over deep intra-abdominal pain and shoulder pain only at the time of awakening. Afterwards, superficial and deep pain decreased to insignificant levels in 6 hours. Bilateral ultrasound-guided sRSB was effective only during the first hour. This limited benefit should be balanced against the time and risks entailed in performing RSB. PMID:27495072

  1. Cranial Ultrasound/Head Ultrasound

    MedlinePlus

    ... waves. Ultrasound imaging, also called ultrasound scanning or sonography , involves the use of a small transducer (probe) and ultrasound gel placed directly on the skin. High-frequency sound waves are transmitted from the ...

  2. An ultrasound-guided fascia iliaca catheter technique does not impair ambulatory ability within a clinical pathway for total hip arthroplasty

    PubMed Central

    Mudumbai, Seshadri C.; Kim, T. Edward; Howard, Steven K.; Giori, Nicholas J.; Woolson, Steven; Ganaway, Toni; Kou, Alex; King, Robert

    2016-01-01

    Background Both neuraxial and peripheral regional analgesic techniques offer postoperative analgesia for total hip arthroplasty (THA) patients. While no single technique is preferred, quadriceps muscle weakness from peripheral nerve blocks may impede rehabilitation. We designed this study to compare postoperative ambulation outcome in THA patients who were treated with a new ultrasound-guided fascia iliaca catheter (FIC) technique or intrathecal morphine (ITM). Methods We reviewed the electronic health records of a sequential series of primary unilateral THA patients who were part of a standardized clinical pathway; apart from differences in regional analgesic technique, all other aspects of the pathway were the same. Our primary outcome was total ambulation distance (meters) combined for postoperative days 1 and 2. Secondary outcomes included daily opioid consumption (morphine milligram equivalents) and analgesic-related side effects. We examined the association between the primary outcome and analgesic technique by performing crude and adjusted ordinary least-squares linear regression. A P value < 0.05 was considered statistically-significant. Results The study analyzed the records of 179 patients (fascia iliaca, n = 106; intrathecal, n = 73). The primary outcome (total ambulation distance) did not differ between the groups (P = 0.08). Body mass index (BMI) was the only factor (β = -1.7 [95% CI -0.5 to -2.9], P < 0.01) associated with ambulation distance. Opioid consumption did not differ, while increased pruritus was seen in the intrathecal group (P < 0.01). Conclusions BMI affects postoperative ambulation outcome after hip arthroplasty, whereas the type of regional analgesic technique used does not. An ultrasound-guided FIC technique offers similar analgesia with fewer side effects when compared with ITM. PMID:27482314

  3. An automated technique for potential differentiation of ovarian mature teratomas from other benign tumours using neural networks classification of 2D ultrasound static images: a pilot study

    NASA Astrophysics Data System (ADS)

    Al-karawi, Dhurgham; Sayasneh, A.; Al-Assam, Hisham; Jassim, Sabah; Page, N.; Timmerman, D.; Bourne, T.; Du, Hongbo

    2017-05-01

    Ovarian cysts are a common pathology in women of all age groups. It is estimated that 5-10% of women have a surgical intervention to remove an ovarian cyst in their lifetime. Given this frequency rate, characterization of ovarian masses is essential for optimal management of patients. Patients with benign ovarian masses can be managed conservatively if they are asymptomatic. Mature teratomas are common benign ovarian cysts that occur, in most cases, in premenopausal women. These ovarian cysts can contain different types of human tissue including bone, cartilage, fat, hair, or other tissue. If they are causing no symptoms, they can be harmless and may not require surgery. Subjective assessment by ultrasound examiners has a high diagnostic accuracy when characterising mature teratomas from other types of tumours. The aim of this study is to develop a computerised technique with the potential to characterise mature teratomas and distinguish them from other types of benign ovarian tumours. Local Binary Pattern (LBP) was applied to extract texture features that are specific in distinguishing teratomas. Neural Networks (NN) was then used as a classifier for recognising mature teratomas. A pilot sample set of 130 B-mode static ovarian ultrasound images (41 mature teratomas tumours and 89 other types of benign tumours) was used to test the effectiveness of the proposed technique. Test results show an average accuracy rate of 99.4% with a sensitivity of 100%, specificity of 98.8% and positive predictive value of 98.9%. This study demonstrates that the NN and LBP techniques can accurately classify static 2D B-mode ultrasound images of benign ovarian masses into mature teratomas and other types of benign tumours.

  4. Biogeosystem technique as a method to overcome the Biological and Environmental Hazards of modern Agricultural, Irrigational and Technological Activities

    NASA Astrophysics Data System (ADS)

    Kalinitchenko, Valery; Batukaev, Abdulmalik; Zinchenko, Vladimir; Zarmaev, Ali; Magomadov, Ali; Chernenko, Vladimir; Startsev, Viktor; Bakoev, Serojdin; Dikaev, Zaurbek

    2014-05-01

    Modern challenge for humanity is to replace the paradigm of nature use and overcome environmental hazards of agronomy, irrigation, industry, and other human activities in biosphere. It is utterly reasonable to stop dividing biosphere on shares - the human habitat and the environment. In the 21st century it is an outdated anthropocentrism. Contradicting himself to biosphere Humankind has the problems. The new paradigm of biosphere control by methods of Biogeosystem technique is on agenda of Humankind. Key directions of Biogeosystem technique. Tillage. Single rotary milling 20…30-50…60 sm soil layer optimizes the evolution and environment of soil, creates a favorable conditions for the rhizosphere, increases the biological productivity of biosphere by 30-50% compared to the standard agricultural practices for the period up to 40 years. Recycle material. Recycling of mineral and organic substances in soil layer of 20…30-50…60 sm in rotary milling soil processing provides wastes clean return to biosphere. Direct intrasoil substances synthesis. Environmentally friendly robot wasteless nanotechnology provides direct substances synthesis, including fertilizers, inside the soil. It eliminates the prerequisites of the wastes formation under standard industrial technologies. Selective substance's extraction from soil. Electrochemical robotic nanotechnology provides selective substances extraction from soil. The technology provides recovery, collection and subsequent safe industrial use of extracted substances out of landscape. Saving fresh water. An important task is to save fresh water in biosphere. Irrigation spends water 4-5 times more of biological requirements of plants, leads to degradation of soil and landscape. The intrasoil pulse continuous-discrete paradigm of irrigation is proposed. It provides the soil and landscape conservation, increases the biological productivity, save the fresh water up to 10-20 times. The subsurface soil rotary processing and

  5. Differentiating between spatial and temporal effects by applying modern data analyzing techniques to measured soil moisture data

    NASA Astrophysics Data System (ADS)

    Hohenbrink, Tobias L.; Lischeid, Gunnar; Schindler, Uwe

    2013-04-01

    Large data sets containing time series of soil hydrological variables exist due to extensive monitoring work in the last decades. The interplay of different processes and influencing factors cause spatial and temporal patterns which contribute to the total variance. That implies that monitoring data sets contain information about the most relevant processes. That information can be extracted using modern data analysis techniques. Our objectives were (i) to decompose the total variance of an example data set of measured soil moisture time series in independent components and (ii) relate them to specific influencing factors. Soil moisture had been measured at 12 plots in an Albeluvisol located in Müncheberg, northeastern Germany, between May 1st, 2008 and July 1st, 2011. Each plot was equipped with FDR probes in 7 depths between 30 cm and 300 cm. Six plots were cultivated with winter rye and silage maize (Crop Rotation System I) and the other six with silage maize, winter rye/millet, triticale/lucerne and lucerne (Crop Rotation System II). We applied a principal component analysis to the soil moisture data set. The first component described the mean behavior in time of all soil moisture time series. The second component reflected the impact of soil depth. Together they explained 80 % of the data set's total variance. An analysis of the first two components confirmed that measured plots showed similar signal damping extend in each depth. The fourth component revealed the impact of the two different crop rotation systems which explained about 4 % of the total variance and 13 % of the spatial variance of soil moisture data. That is only a minor fraction compared to small scale soil texture heterogeneity effects. Principal component analysis has proven to be a useful tool to extract less apparent signals.

  6. Ultrasound-Induced Organogel Formation Followed by Thin Film Fabrication via Simple Doctor Blading Technique for Field-Effect Transistor Applications.

    PubMed

    Xu, Jiaju; Wang, Yulong; Shan, Haiquan; Lin, Yiwei; Chen, Qian; Roy, V A L; Xu, Zongxiang

    2016-07-27

    We demonstrate doctor blading technique to fabricate high performance transistors made up of printed small molecular materials. In this regard, we synthesize a new soluble phthalocyanine, tetra-n-butyl peripheral substituted copper(II) phthalocaynine (CuBuPc), that can easily undergo gel formation upon ultrasonic irradiation, leading to the formation of three-dimensional (3D) network composed of one-dimensional (1D) nanofibers structure. Finally, taking the advantage of thixotropic nature of the CuBuPc organogel, we use the doctor blade processing technique that limits the material wastage for the fabrication of transistor devices. Due to the ultrasound induced stronger π-π interaction, the transistor fabricated by doctor blading based on CuBuPc organogel exhibits significant increase in charge carrier mobility in comparison with other solution process techniques, thus paving a way for a simple and economically viable preparation of electronic circuits.

  7. Effective porosity and density of carbonate rocks (Maynardville Limestone and Copper Ridge Dolomite) within Bear Creek Valley on the Oak Ridge Reservation based on modern petrophysical techniques

    SciTech Connect

    Dorsch, J.

    1997-02-01

    The purpose of this study is to provide quantitative data on effective porosity of carbonate rock from the Maynardville Limestone and Copper Ridge Dolomite within Bear Creek Valley based on modern petrophysical techniques. The data will be useful for groundwater-flow and contaminant-flow modeling in the vicinity of the Y-12 Plant on the Oak Ridge Reservation (ORR). Furthermore, the data provides needed information on the amount of interconnected pore space potentially available for operation of matrix diffusion as a transport process within the fractured carbonate rock. A second aspect of this study is to compare effective porosity data based on modern petrophysical techniques to effective porosity data determined earlier by Goldstrand et al. (1995) with a different technique. An added bonus of the study is quantitative data on the bulk density and grain density of dolostone and limestone of the Maynardville Limestone and Copper Ridge Dolomite which might find use for geophysical modeling on the ORR.

  8. Comparison of Acute and Late Toxicities for Three Modern High-Dose Radiation Treatment Techniques for Localized Prostate Cancer

    SciTech Connect

    Mohammed, Nasiruddin; Kestin, Larry; Ghilezan, Mihai; Krauss, Daniel; Vicini, Frank; Brabbins, Donald; Gustafson, Gary; Ye Hong; Martinez, Alavaro

    2012-01-01

    Purpose: We compared acute and late genitourinary (GU) and gastrointestinal (GI) toxicities in prostate cancer patients treated with three different high-dose radiation techniques. Methods and Materials: A total of 1,903 patients with localized prostate cancer were treated with definitive RT at William Beaumont Hospital from 1992 to 2006: 22% with brachytherapy alone (BT), 55% with image-guided external beam (EB-IGRT), and 23% external beam with high-dose-rate brachytherapy boost (EBRT+HDR). Median dose with BT was 120 Gy for LDR and 38 Gy for HDR (9.5 Gy Multiplication-Sign 4). Median dose with EB-IGRT was 75.6 Gy (PTV) to prostate with or without seminal vesicles. For EBRT+HDR, the pelvis was treated to 46 Gy with an additional 19 Gy (9.5 Gy Multiplication-Sign 2) delivered via HDR. GI and GU toxicity was evaluated utilizing the NCI-CTC criteria (v.3.0). Median follow-up was 4.8 years. Results: The incidences of any acute {>=} Grade 2 GI or GU toxicities were 35%, 49%, and 55% for BT, EB-IGRT, and EBRT+HDR (p < 0.001). Any late GU toxicities {>=} Grade 2 were present in 22%, 21%, and 28% for BT, EB-IGRT, and EBRT+HDR (p = 0.01), respectively. Patients receiving EBRT+HDR had a higher incidence of urethral stricture and retention, whereas dysuria was most common in patients receiving BT. Any Grade {>=}2 late GI toxicities were 2%, 20%, and 9% for BT, EB-IGRT, and EBRT+HDR (p < 0.001). Differences were most pronounced for rectal bleeding, with 3-year rates of 0.9%, 20%, and 6% (p < 0.001) for BT, EB-IGRT, and EBRT+HDR respectively. Conclusions: Each of the three modern high-dose radiation techniques for localized prostate cancer offers a different toxicity profile. These data can help patients and physicians to make informed decisions regarding radiotherapy for prostate andenocarcinoma.

  9. Comparing the performance of different ultrasonic images enhancement for speckle noise reduction in ultrasound images using techniques: a preference study

    NASA Astrophysics Data System (ADS)

    Rana, Md. Shohel; Sarker, Kaushik; Bhuiyan, Touhid; Hassan, Md. Maruf

    2017-06-01

    Diagnostic ultrasound (US) is an important tool in today's sophisticated medical diagnostics. Nearly every medical discipline benefits itself from this relatively inexpensive method that provides a view of the inner organs of the human body without exposing the patient to any harmful radiations. Medical diagnostic images are usually corrupted by noise during their acquisition and most of the noise is speckle noise. To solve this problem, instead of using adaptive filters which are widely used, No-Local Means based filters have been used to de-noise the images. Ultrasound images of four organs such as Abdomen, Ortho, Liver, Kidney, Brest and Prostrate of a Human body have been used and applied comparative analysis study to find out the output. These images were taken from Siemens SONOLINE G60 S System and the output was compared by matrices like SNR, RMSE, PSNR IMGQ and SSIM. The significance and compared results were shown in a tabular format.

  10. Tomographic ultrasound imaging of the fetal heart: a new technique for identifying normal and abnormal cardiac anatomy.

    PubMed

    Devore, Greggory R; Polanko, Bardo

    2005-12-01

    In 2003 and 2004, the American College of Radiology, the American Institute of Ultrasound in Medicine, and the American College of Obstetricians and Gynecologists published guidelines for the standard ultrasound examination of the fetus. Each group recommended that the outflow tracts of the fetal heart be examined if technically feasible. One method to accomplish this task is to perform a free-hand sweep of the transducer beam directed in a transverse plane from the 4-chamber view to the fetal neck. One problem with this approach is that the examiner may not direct the beam transversely and, therefore, may not accurately identify the outflow tract anatomy. A new technology, tomographic ultrasound imaging (TUI), allows the examiner to obtain a volume data set that simultaneously displays multiple images at specific distances from the 4-chamber view. This study examined TUI technology for identifying normal and abnormal fetal cardiac anatomy with the use of either static or spatiotemporal image correlation volume data sets. The 4 views used in the screening examination of the outflow tracts of the fetal heart (4-chamber, 5-chamber, 3-vessel, and tracheal views) could be identified with the use of TUI technology in fetuses between 13 and 40 weeks' gestation. Examples of fetuses with abnormal cardiac anatomy of the outflow tracts (tetralogy of Fallot, transposition of the great vessels, and pulmonary stenosis) all showed abnormal anatomy on TUI. Tomographic ultrasound imaging technology enables the fetal examiner to evaluate the 4-chamber view and the outflow tracts in a systematic manner to identify normal and abnormal cardiac anatomy.

  11. Periapical surgery using the ultrasound technique and silver amalgam retrograde filling. A study of 71 teeth with 100 canals.

    PubMed

    Martí-Bowen, Eva; Peñarrocha-Diago, Miguel; García-Mira, Berta

    2005-04-01

    Periapical surgery using ultrasound allows the treatment of root canals of difficult access, with the sacrifice of little root tissue. As a result, periapical disorders which were condemned to treatment failure in the past can now be dealt with successfully. In 71 teeth presenting 100 root canals treated with ultrasound and subjected to retrograde filling with silver amalgam, the course and short-term success of management was evaluated in relation to lesion size, the magnitude of apical resection, and the size of the retrograde filling cavity. The duration of follow-up was one year, with post-treatment controls after 6 and 12 months. After 6 months, the percentage clinical and radiological success was 92% and 58%, respectively. One year after periapical surgery the corresponding percentages were 95% and 80%. Global success after 6 months was 63%, versus 84.2% after 12 months. No statistically significant relation was observed between treatment success and the size of the periapical lesion, the amount of apex resected, or the size of retrograde filling. Periapical surgery using ultrasound and retrograde filling with silver amalgam affords a high success rate after 12 months.

  12. Monitoring radiofrequency ablation using real-time ultrasound Nakagami imaging combined with frequency and temporal compounding techniques.

    PubMed

    Zhou, Zhuhuang; Wu, Shuicai; Wang, Chiao-Yin; Ma, Hsiang-Yang; Lin, Chung-Chih; Tsui, Po-Hsiang

    2015-01-01

    Gas bubbles induced during the radiofrequency ablation (RFA) of tissues can affect the detection of ablation zones (necrosis zone or thermal lesion) during ultrasound elastography. To resolve this problem, our previous study proposed ultrasound Nakagami imaging for detecting thermal-induced bubble formation to evaluate ablation zones. To prepare for future applications, this study (i) created a novel algorithmic scheme based on the frequency and temporal compounding of Nakagami imaging for enhanced ablation zone visualization, (ii) integrated the proposed algorithm into a clinical scanner to develop a real-time Nakagami imaging system for monitoring RFA, and (iii) investigated the applicability of Nakagami imaging to various types of tissues. The performance of the real-time Nakagami imaging system in visualizing RFA-induced ablation zones was validated by measuring porcine liver (n = 18) and muscle tissues (n = 6). The experimental results showed that the proposed algorithm can operate on a standard clinical ultrasound scanner to monitor RFA in real time. The Nakagami imaging system effectively monitors RFA-induced ablation zones in liver tissues. However, because tissue properties differ, the system cannot visualize ablation zones in muscle fibers. In the future, real-time Nakagami imaging should be focused on the RFA of the liver and is suggested as an alternative monitoring tool when advanced elastography is unavailable or substantial bubbles exist in the ablation zone.

  13. Monitoring Radiofrequency Ablation Using Real-Time Ultrasound Nakagami Imaging Combined with Frequency and Temporal Compounding Techniques

    PubMed Central

    Zhou, Zhuhuang; Wu, Shuicai; Wang, Chiao-Yin; Ma, Hsiang-Yang; Lin, Chung-Chih; Tsui, Po-Hsiang

    2015-01-01

    Gas bubbles induced during the radiofrequency ablation (RFA) of tissues can affect the detection of ablation zones (necrosis zone or thermal lesion) during ultrasound elastography. To resolve this problem, our previous study proposed ultrasound Nakagami imaging for detecting thermal-induced bubble formation to evaluate ablation zones. To prepare for future applications, this study (i) created a novel algorithmic scheme based on the frequency and temporal compounding of Nakagami imaging for enhanced ablation zone visualization, (ii) integrated the proposed algorithm into a clinical scanner to develop a real-time Nakagami imaging system for monitoring RFA, and (iii) investigated the applicability of Nakagami imaging to various types of tissues. The performance of the real-time Nakagami imaging system in visualizing RFA-induced ablation zones was validated by measuring porcine liver (n = 18) and muscle tissues (n = 6). The experimental results showed that the proposed algorithm can operate on a standard clinical ultrasound scanner to monitor RFA in real time. The Nakagami imaging system effectively monitors RFA-induced ablation zones in liver tissues. However, because tissue properties differ, the system cannot visualize ablation zones in muscle fibers. In the future, real-time Nakagami imaging should be focused on the RFA of the liver and is suggested as an alternative monitoring tool when advanced elastography is unavailable or substantial bubbles exist in the ablation zone. PMID:25658424

  14. Real-time 3D ultrasound fetal image enhancment techniques using motion-compensated frame rate up-conversion

    NASA Astrophysics Data System (ADS)

    Lee, Gun-Ill; Park, Rae-Hong; Song, Young-Seuk; Kim, Cheol-An; Hwang, Jae-Sub

    2003-05-01

    In this paper, we present a motion compensated frame rate up-conversion method for real-time three-dimensional (3-D) ultrasound fetal image enhancement. The conventional mechanical scan method with one-dimensional (1-D) array converters used for 3-D volume data acquisition has a slow frame rate of multi-planar images. This drawback is not an issue for stationary objects, however in ultrasound images showing a fetus of more than about 25 weeks, we perceive abrupt changes due to fast motions. To compensate for this defect, we propose the frame rate up-conversion method by which new interpolated frames are inserted between two input frames, giving smooth renditions to human eyes. More natural motions can be obtained by frame rate up-conversion. In the proposed algorithm, we employ forward motion estimation (ME), in which motion vectors (MVs) ar estimated using a block matching algorithm (BMA). To smooth MVs over neighboring blocks, vector median filtering is performed. Using these smoothed MVs, interpolated frames are reconstructed by motion compensation (MC). The undesirable blocking artifacts due to blockwise processing are reduced by block boundary filtering using a Gaussian low pass filter (LPF). The proposed method can be used in computer aided diagnosis (CAD), where more natural 3-D ultrasound images are displayed in real-time. Simulation results with several real test sequences show the effectiveness of the proposed algorithm.

  15. Extraction of Natural Antioxidants from the Thelephora ganbajun Mushroom by an Ultrasound-Assisted Extraction Technique and Evaluation of Antiproliferative Activity of the Extract against Human Cancer Cells

    PubMed Central

    Xu, Dong-Ping; Zheng, Jie; Zhou, Yue; Li, Ya; Li, Sha; Li, Hua-Bin

    2016-01-01

    The Thelephora ganbajun mushroom has been found to be a potential rich source of natural antioxidants. In this study, an ultrasound-assisted extraction (UAE) technique together with GRAS (generally recognized as safe) solvents (ethanol and water) was used to maximize the extraction of antioxidants from Thelephora ganbajun. Five extraction parameters (ethanol concentration, solvent to solid ratio, extraction time, temperature and ultrasound power) were investigated by single-factor experiments, and then a central composite rotatable design was employed to study interaction of three key extraction parameters. The optimum conditions were as follows: 57.38% ethanol, 70.15 mL/g solvent to solid ratio, 10.58 min extraction time, 40 °C extraction temperature and 500 W ultrasound power. Under the optimum conditions, the antioxidant activity obtained was 346.98 ± 12.19 µmol Trolox/g DW, in accordance with the predicted value of 344.67 µmol Trolox/g DW. Comparison of UAE with conventional maceration and Soxhlet extraction, the UAE method showed stronger extract efficiency in a shorter extraction time. These results showed that UAE was an effective technique to extract antioxidants from Thelephora ganbajun. Furthermore, the extracts obtained under the optimized conditions exhibited antiproliferative activities toward human lung (A549), breast (MCF-7), liver (HepG2) and colon (HT-29) cancer cells, especially for liver and lung cancer cells. In addition, rutin, 2-hydrocinnamic acid and epicatechin were identified in the extract, which might contribute to antioxidant and antiproliferative activities. PMID:27706082

  16. Clinical, histological, and ultrasound follow-up of breast reconstruction with one-stage muscle-sparing "wrap" technique: A single-center experience.

    PubMed

    Onesti, Maria Giuseppina; Maruccia, Michele; Di Taranto, Giuseppe; Albano, Antonio; Soda, Giuseppe; Ballesio, Laura; Scuderi, Nicolò

    2017-06-29

    Prepectoral implant placement and complete coverage with porcine acellular matrix after mastectomy is a new concept in breast surgery presented in few cases in the literature. This paper aimed to present our single-center experience in one-stage breast reconstruction muscle-sparing "wrap" technique by evaluating clinical and aesthetic outcomes, ultrasound and histological examination, and patient quality of life. From January 2014 to January 2017, 52 patients (40 unilateral, 12 bilateral) underwent one-stage muscle-sparing breast reconstructions with Braxon(®) acellular dermal matrix and implant. In 3 patients, a surgical biopsy and histological examination with immunohistochemical analysis of the periprosthetic tissue were performed. All patients underwent breast ultrasound examination, and the occurrence of capsular contracture was assessed through the Baker classification and by measuring the mammary compliance scores with the Antoon Paar Mammary compliance system. Breast appearance was evaluated using a visual analogue scale (VAS) and in terms of quality of life using the EOCRT QLQ C-30 and QLQ BR-23 questionnaires. Early and late postoperative complications are reported. Histological and ultrasound evaluation showed a complete integration of the matrix. According to the VAS scale, the EOCRT QLQ C-30, and QLQ BR-23, patients' satisfaction resulted in a high score in terms of quality of life and aesthetic outcomes. The results of this new surgical technique in selected cases are promising in terms of effectiveness and low rate of postoperative complications, but further long-terms evaluations are required. Copyright © 2017 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  17. Randomized double-blind clinical trial comparing two anesthetic techniques for ultrasound-guided transvaginal follicular puncture.

    PubMed

    Oliveira, Gilvandro Lins de; Serralheiro, Fernando Cesar; Fonseca, Fernando Luiz Affonso; Ribeiro, Onésimo Duarte; Adami, Fernando; Christofolini, Denise Maria; Bianco, Bianca; Barbosa, Caio Parente

    2016-01-01

    To compare the anesthetic techniques using propofol and fentanyl versus midazolam and remifentanil associated with a paracervical block with lidocaine in performing ultrasound-guided transvaginal oocyte aspiration. A randomized double-blind clinical trial (#RBR-8kqqxh) performed in 61 women submitted to assisted reproductive treatment. The patients were divided into two groups: anesthetic induction with 1mcg/kg of fentanyl associated with 1.5mg/kg of propofol (FP Group, n=32), in comparison with anesthetic induction using 0.075mg/kg of midazolam associated with 0.25mcg/kg/min of remifentanil, and paracervical block with 3mL of 2% lidocaine (MRPB Group, n=29). Main outcome measures: human reproduction outcomes, modified Aldrete-Kroulik index, hemodynamic parameters, and salivary cortisol. The results revealed a higher number of embryos formed in the FP Group (p50=2 versus 1; p=0.025), gestation rate two times higher in the FP Group (44.4% versus 22.2%; p=0.127), less time to reach AK=10 in the MRPB Group (p50=10 versus 2; p<0.001), and lower mean of hemodynamic parameters in the MRPB Group (p<0.05). Anesthesia with fentanyl and propofol as well as with midazolam, remifentanil, and paracervical block offered satisfactory anesthetic conditions when performing assisted reproduction procedures, providing comfort for the patient and physician. Comparar as técnicas anestésicas utilizando propofol e fentanil contra midazolam e remifentanil associados a um bloqueio paracervical com lidocaína na aspiração de oócitos transvaginal guiada por ultrassom. Ensaio clínico randomizado duplocego (#RBR-8kqqxh) realizado em 61 mulheres submetidas ao tratamento de reprodução assistida. As pacientes foram divididas em dois grupos: um grupo foi submetido à indução da anestesia com 1mcg/kg de fentanil associada com 1,5mg/kg de propofol (Grupo FP, n=32), em comparação com ao grupo submetido à indução da anestesia utilizando 0,075mg/kg de midazolam associada com 0,25mcg

  18. Randomized, prospective, observational simulation study comparing residents' needle-guided vs free-hand ultrasound techniques for central venous catheter access.

    PubMed

    Ball, R D; Scouras, N E; Orebaugh, S; Wilde, J; Sakai, T

    2012-01-01

    Short-axis ultrasound-guided placement of central venous catheters (CVCs) is widely accepted as safe practice. However, utilizing the long-axis approach could further improve safety, as it allows for better visualization of the needle as it is advanced to the target vessel. However, the long-axis approach has not widely been used due to the technical difficulty. Recently, a new needle guidance device has become available to aid in the long-axis approach. We hypothesized that the use of a needle guide paired with the long-axis approach would facilitate puncture of the target vessel in a simulation model more effectively than similar free-hand techniques. A prospective observational study of anaesthesia residents using a CVC partial-task training device was conducted. Each resident performed needle puncture of the target vessel with three different techniques, assigned in random order: short-axis free hand (S-FH), long-axis free hand (L-FH), and long-axis needle guide (NG). To prove the effectiveness of the needle guide, the fraction of time the needle tip remained in view of the ultrasound was recorded and compared. Time required for completing the task and the number of needle sticks and needle re-directions were compared. Thirty-three residents participated in the study. The fraction of time the needle tip remained in view of the ultrasound was significantly higher for the residents using NG [0.90 (0.10)] compared with residents using the other techniques [L-FH: 0.36 (0.20), S-FH: 0.18 (0.10)] (P<0.001). For each resident, the use of the needle guide in the long-axis approach increased visualization by 352 (276)% compared with that of L-FH and by 1028 (1804) % compared with that of S-FH. There was no significant difference in time required to puncture the target between NG [23.7 (14.6) s] and L-FH [30.3 (36.5) s] (P=0.21); however, both were significantly longer than S-FH [17.0 (13.3) s] (P=0.012). The numbers of needle sticks and of needle re-directions did not

  19. Combination of modified mixing technique and low frequency ultrasound to control the elution profile of vancomycin-loaded acrylic bone cement

    PubMed Central

    Wendling, A.; Mar, D.; Wischmeier, N.; Anderson, D.

    2016-01-01

    Objectives The objective of this study was to determine if combining variations in mixing technique of antibiotic-impregnated polymethylmethacrylate (PMMA) cement with low frequency ultrasound (LFUS) improves antibiotic elution during the initial high phase (Phase I) and subsequent low phase (Phase II) while not diminishing mechanical strength. Methods Three batches of vancomycin-loaded PMMA were prepared with different mixing techniques: a standard technique; a delayed technique; and a control without antibiotic. Daily elution samples were analysed using flow injection analysis (FIA). Beginning in Phase II, samples from each mix group were selected randomly to undergo either five, 15, 45, or 0 minutes of LFUS treatment. Elution amounts between LFUS treatments were analysed. Following Phase II, compression testing was done to quantify strength. A-priori t-tests and univariate ANOVAs were used to compare elution and mechanical test results between the two mix groups and the control group. Results The delayed technique showed a significant increase in elution on day one compared with the standard mix technique (p < 0.001). The transition point from Phase I to Phase II occurred on day ten. LFUS treatments significantly increased elution amounts for all groups above control. Delayed technique resulted in significantly higher elution amounts for the five-minute- (p = 0.004) and 45-minute- (p < 0.001) duration groups compared with standard technique. Additionally, the correlations between LFUS duration and total elution amount for both mix techniques were significant (p = 0.03). Both antibiotic-impregnated groups exhibited a significant decrease in offset yield stress compared with the control group (p < 0.001), however, their lower 95% confidence intervals were all above the 70 MPa limit defined by International Standards Organization (ISO) 5833-2 reference standard for acrylic bone cement. Conclusion The combination of a delayed mix technique with LFUS treatments

  20. Breast ultrasound.

    PubMed

    Ueno, E

    1996-03-01

    to the diagnosis of breast cancer. Breast cancer is rich in blood vessels. The feeding arteries flow directly into the tumor and are characterized by tortuosity and flexion. Since the intraductal spread of breast cancer can easily be evaluated, ultrasound has come to play an important role in breast conserving treatment. Breast cancer with intraductal spreading causes dilation of the mammary ducts, and the resolution of ultrasound at present has been improved to the degree that this dilation is shown as a tubular hypoechoic area. With the progress made in imaging diagnosis, nonpalpable breast cancer has increased and ultrasonically-guided aspiration cytology and biopsy techniques have been developed to obtain definite diagnoses of these lesions. In cases of micro-calcification detected by mammography, ultrasonically guided biopsy is recommended when identification by ultrasound is possible. Since this is a simple technique, it should be mastered.

  1. A Modern Automatic Chamber Technique as a Powerful Tool for CH4 and CO2 Flux Monitoring

    NASA Astrophysics Data System (ADS)

    Mastepanov, M.; Christensen, T. R.; Lund, M.; Pirk, N.

    2014-12-01

    A number of similar systems were used for monitoring of CH4 and CO2 exchange by the automatic chamber method in a range of different ecosystems. The measurements were carried out in northern Sweden (mountain birch forest near Abisko, 68°N, 2004-2010), southern Sweden (forest bog near Hässleholm, 56°N, 2007-2014), northeastern Greenland (arctic fen in Zackenberg valley, 74°N, 2005-2014), southwestern Greenland (fen near Nuuk, 64°N, 2007-2014), central Svalbard (arctic fen near Longyearbyen, 78°N, 2011-2014). Those in total 37 seasons of measurements delivered not only a large amount of valuable flux data, including a few novel findings (Mastepanov et al., Nature, 2008; Mastepanov et al., Biogeosciences, 2013), but also valuable experience with implementation of the automatic chamber technique using modern analytical instruments and computer technologies. A range of high resolution CH4 analysers (DLT-100, FMA, FGGA - Los Gatos Research), CO2 analyzers (EGM-4, SBA-4 - PP Systems; Li-820 - Li-Cor Biosciences), as well as Methane Carbon Isotope Analyzer (Los Gatos Research) has shown to be suitable for precise measurements of fluxes, from as low as 0.1 mg CH4 m-1 d-1 (wintertime measurements at Zackenberg, unpublished) to as high as 2.4 g CH4 m-1 d-1 (autumn burst 2007 at Zackenberg, Mastepanov et al., Nature, 2008). Some of these instruments had to be customized to accommodate 24/7 operation in harsh arctic conditions. In this presentation we will explain some of these customizations. High frequency of concentration measurements (1 Hz in most cases) provides a unique opportunity for quality control of flux calculations; on the other hand, this enormous amount of data can be analyzed only using highly automated algorithms. A specialized software package was developed and improved through the years of measurements and data processing. This software automates the data flow from raw concentration data of different instruments and sensors and various status records

  2. Role of pelvic ultrasound simulation.

    PubMed

    Arya, Sushila; Mulla, Zuber D; Kupesic Plavsic, Sanja

    2017-10-10

    Pelvic ultrasound is a critical diagnostic imaging tool in obstetrics and gynaecology. Training opportunities in transvaginal ultrasound have not kept pace with the demand among learners because of the increased complexity of modern ultrasound technology and duty-hour restrictions. Ultrasound simulation training has the potential to overcome this gap. Training opportunities in transvaginal ultrasound have not kept pace with the demand OBJECTIVE: Our study aimed to determine the usefulness, applicability and attitudes toward pelvic ultrasound simulation training among residents, sonographers and practising doctors. Pelvic ultrasound simulation activity using high-fidelity virtual reality ultrasound simulators lasted 4 hours and consisted of three modules: abnormal uterine bleeding, adnexal masses and bleeding in pregnancy. All learners completed a pre- and post-encounter quiz, and an anonymous post-simulation survey on the relevance of ultrasound simulation to clinical learning, and its usefulness to improve scanning performance and interpretation skills. Thirty-one participants attended the workshop, and 28 (90.3%) of them responded to the survey. Five respondents agreed and 23 strongly agreed that pelvic ultrasound simulation applies to their clinical ultrasound practice, and seven of them agreed and 21 strongly agreed that their performance of ultrasound and interpretation skills will be improved following their simulation training. The average post-activity knowledge score for all three topics significantly increased (paired Student's t-test, p < 0.0001). All 28 respondents believe that ultrasound simulation is a useful complement to learning with real patients, with the potential to improve their pelvic ultrasound performance, interpretation skills and clinical reasoning. © 2017 John Wiley & Sons Ltd and The Association for the Study of Medical Education.

  3. Cardiac 4D Ultrasound Imaging

    NASA Astrophysics Data System (ADS)

    D'hooge, Jan

    Volumetric cardiac ultrasound imaging has steadily evolved over the last 20 years from an electrocardiography (ECC) gated imaging technique to a true real-time imaging modality. Although the clinical use of echocardiography is still to a large extent based on conventional 2D ultrasound imaging it can be anticipated that the further developments in image quality, data visualization and interaction and image quantification of three-dimensional cardiac ultrasound will gradually make volumetric ultrasound the modality of choice. In this chapter, an overview is given of the technological developments that allow for volumetric imaging of the beating heart by ultrasound.

  4. Ultrasound-guided thyroid nodule fine-needle biopsies--comparison of sample adequacy with different sampling techniques, different needle sizes, and with/without onsite cytological analysis.

    PubMed

    Cerit, Mahinur; Yücel, Cem; Göçün, Pınar Uyar; Poyraz, Aylar; Cerit, Ethem Turgay; Taneri, Ferit

    2015-01-01

    The aim of this study was to compare the diagnostic adequacy of thyroid samples obtained by aspiration or capillary biopsy techniques, with 22 or 27 gauge needles, and with or without on-site cytological analysis (OCA). Four hundred patients with thyroid nodules underwent ultrasound (US)-guided fine-needle biopsies. Patients were divided into eight groups according to needle size (22 vs. 27 gauge), biopsy technique (aspiration vs. capillary), and whether or not OCA was performed. Sample adequacy rates were calculated for each group and subgroups and compared using chi-square tests. When all nodes were evaluated (n = 400), the adequacy rate was significantly greater with the capillary than with the aspiration technique (97% vs. 91.5%, p = 0.032) and when OCA was than was not performed (97% vs. 91.5%, p = 0.032). When only solid nodules were evaluated (n = 205) the adequacy rate was also significantly greater with the capillary than with the aspiration technique (98.9% vs. 89.7%, p = 0.008) and when OCA was than was not performed (97.9% vs. 89.6%, p = 0.014). In contrast, the adequacy rate was similar for 22 and 27 gauge needles (94.2% vs. 93.1%, p = 0.733). Optimal results were obtained with the capillary technique and OCA. The capillary technique and OCA should be the preferred approach in thyroid nodule biopsy, optimising adequacy rates and patient comfort.

  5. MRI-guided vacuum-assisted breast biopsy: comparison with stereotactically guided and ultrasound-guided techniques.

    PubMed

    Imschweiler, Thomas; Haueisen, Harald; Kampmann, Gert; Rageth, Luzi; Seifert, Burkhardt; Rageth, Christoph; Freiwald, Bianka; Kubik-Huch, Rahel A

    2014-01-01

    To analyse the development of MRI-guided vacuum-assisted biopsy (VAB) in Switzerland and to compare the procedure with stereotactically guided and ultrasound-guided VAB. We performed a retrospective analysis of VABs between 2009 and 2011. A total of 9,113 VABs were performed. Of these, 557 were MRI guided. MRI-guided VAB showed the highest growth rate (97 %) of all three procedures. The technical success rates for MRI-guided, stereotactically guided and ultrasound-guided VAB were 98.4 % (548/557), 99.1 % (5,904/5,960) and 99.6 % (2,585/2,596), respectively. There were no significant differences (P = 0.12) between the MRI-guided and the stereotactically guided procedures. The technical success rate for ultrasound-guided VAB was significantly higher than that for MRI-guided VAB (P < 0.001). There were no complications using MRI-guided VAB requiring open surgery. The malignancy diagnosis rate for MRI-guided VAB was similar to that for stereotactically guided VAB (P = 0.35). MRI-guided VAB is a safe and accurate procedure that provides insight into clinical breast findings. • Three vacuum-assisted breast biopsy (VAB) procedures were compared. • Technical success rates were high for all three VAB procedures. • Medical complications were relatively low using all three VAB procedures. • The use of MRI-guided vacuum-assisted breast biopsy is growing.

  6. True Reproducibility of UltraSound Techniques (TRUST): systematic review of reliability studies in obstetrics and gynecology.

    PubMed

    Coelho Neto, M A; Roncato, P; Nastri, C O; Martins, W P

    2015-07-01

    To examine the quality of methods used and the accuracy of the interpretation of agreement in existing studies that examine the reliability of ultrasound measurements and judgments in obstetrics and gynecology. A systematic search of MEDLINE was performed on 25 March 2014, looking for studies that examined the reliability of ultrasound measurements and judgments in obstetrics and gynecology with evaluation of concordance (CCC) or intraclass (ICC) correlation coefficients or kappa as a main objective. Seven hundred and thirty-three records were examined on the basis of their title and abstract, of which 141 full-text articles were examined completely for eligibility. We excluded 29 studies because they did not report CCC/ICC/kappa, leaving 112 studies that were included in our analysis. Two studies reported both ICC and kappa and were counted twice, therefore, the number used as the denominator in the analyses was 114. Only 16/114 (14.0%) studies were considered to be well designed (independent acquisition and blinded analysis) and to have interpreted the results properly. Most errors occurring in the studies are likely to overestimate the reliability of the method examined. The vast majority of published studies examined had important flaws in design, interpretation and/or reporting. Such limitations are important to identify as they might create false confidence in the existing measurements and judgments, jeopardizing clinical practice and future research. Specific guidelines aimed at improving the quality of reproducibility studies that examine ultrasound methods should be encouraged. Copyright © 2014 ISUOG. Published by John Wiley & Sons Ltd.

  7. A comparison of free-hand vs laser-guided long-axis ultrasound techniques in novice users.

    PubMed

    Collins, G B; Fanou, E-M; Young, J; Bhogal, P

    2013-09-01

    The increasing use of point-of-care ultrasonography for targeted procedures justifies a device that helps both novices in training and experts perform the long-axis needle approach. The initial success of traditional needle guidance devices in reducing the time of target procedures is not universal and they can be cumbersome. We aim to investigate whether the less bulky and previously untested laser guide can succeed in reducing procedure time in novice ultrasonographers. 82 medical students with no ultrasound experience volunteered. Random allocation determined whether, during a targeted procedure in a turkey breast and olive phantom, participants were assisted by the laser guide or not. The time taken to pierce the target was recorded at 1-cm depth. The mean procedure time in the laser-assisted (LA) group was 25.1 s (14.0 s; 18.0-25.0 s). The mean procedure time in the free-hand group was 45.5 s (23.0 s; 7.0-55.0 s). The procedure time in the LA group was significantly reduced (p<0.01). The laser guide significantly improved procedure times. It is felt that the cheaper, smaller, easy to integrate, sterile and more user-friendly laser guidance unit may be a better alternative to the needle guide in improving procedure times for the novice ultrasonographer or to assist the expert, during training for, or performance of, ultrasound-guided targeted procedures. Following from the prototype paper, this is the first study to investigate the effectiveness of attaching a laser-guidance device to an ultrasound probe. The device succeeded in reducing the procedure times of targeted procedures.

  8. Value of Ultrasound in Rheumatologic Diseases

    PubMed Central

    Kang, Taeyoung; Horton, Laura; Emery, Paul

    2013-01-01

    The use of musculoskeletal ultrasound in rheumatology clinical practice has rapidly increased over the past decade. Ultrasound has enabled rheumatologists to diagnose, prognosticate and monitor disease outcome. Although international standardization remains a concern still, the use of ultrasound in rheumatology is expected to grow further as costs fall and the opportunity to train in the technique improves. We present a review of value of ultrasound, focusing on major applications of ultrasound in rheumatologic diseases. PMID:23580002

  9. Ultrasound-Guided Suprainguinal Fascia Iliaca Technique Provides Benefit as an Analgesic Adjunct for Patients Undergoing Total Hip Arthroplasty.

    PubMed

    Bullock, W Michael; Yalamuri, Suraj M; Gregory, Stephen H; Auyong, David B; Grant, Stuart A

    2017-02-01

    Analgesia after total hip arthroplasty is often accomplished by the fascia iliaca compartment block, traditionally performed below the inguinal ligament, to anesthetize both femoral and lateral femoral cutaneous nerves. The course of the lateral femoral cutaneous nerve below the inguinal ligament is variable as opposed to consistent above the inguinal ligament in the pelvis. In this case series including 5 patients, we demonstrate that an ultrasound-guided suprainguinal fascia iliaca approach would consistently anesthetize the lateral femoral cutaneous nerve along with anterior cutaneous femoral nerve branches and provide cutaneous analgesia after total hip arthroplasty, as shown by decreased opioid consumption.

  10. Application of modern tools and techniques to maximize engineering productivity in the development of orbital operations plans for the space station progrm

    NASA Technical Reports Server (NTRS)

    Manford, J. S.; Bennett, G. R.

    1985-01-01

    The Space Station Program will incorporate analysis of operations constraints and considerations in the early design phases to avoid the need for later modifications to the Space Station for operations. The application of modern tools and administrative techniques to minimize the cost of performing effective orbital operations planning and design analysis in the preliminary design phase of the Space Station Program is discussed. Tools and techniques discussed include: approach for rigorous analysis of operations functions, use of the resources of a large computer network, and providing for efficient research and access to information.

  11. Application of modern tools and techniques to maximize engineering productivity in the development of orbital operations plans for the space station progrm

    NASA Technical Reports Server (NTRS)

    Manford, J. S.; Bennett, G. R.

    1985-01-01

    The Space Station Program will incorporate analysis of operations constraints and considerations in the early design phases to avoid the need for later modifications to the Space Station for operations. The application of modern tools and administrative techniques to minimize the cost of performing effective orbital operations planning and design analysis in the preliminary design phase of the Space Station Program is discussed. Tools and techniques discussed include: approach for rigorous analysis of operations functions, use of the resources of a large computer network, and providing for efficient research and access to information.

  12. Ultrasound in regional anaesthesia.

    PubMed

    Griffin, J; Nicholls, B

    2010-04-01

    Ultrasound guidance is rapidly becoming the gold standard for regional anaesthesia. There is an ever growing weight of evidence, matched with improving technology, to show that the use of ultrasound has significant benefits over conventional techniques, such as nerve stimulation and loss of resistance. The improved safety and efficacy that ultrasound brings to regional anaesthesia will help promote its use and realise the benefits that regional anaesthesia has over general anaesthesia, such as decreased morbidity and mortality, superior postoperative analgesia, cost-effectiveness, decreased postoperative complications and an improved postoperative course. In this review we consider the evidence behind the improved safety and efficacy of ultrasound-guided regional anaesthesia, before discussing its use in pain medicine, paediatrics and in the facilitation of neuraxial blockade. The Achilles' heel of ultrasound-guided regional anaesthesia is that anaesthetists are far more familiar with providing general anaesthesia, which in most cases requires skills that are achieved faster and more reliably. To this ends we go on to provide practical advice on ultrasound-guided techniques and the introduction of ultrasound into a department.

  13. [Celiac block in paediatric patients using endoscopic ultrasound for management of severe pain due to chronic pancreatitis. Review of the technique in 2 cases].

    PubMed

    Membrillo-Romero, Alejandro; Rascón-Martínez, Dulce María

    Pancreatic diseases such as cancer, idiopathic recurrent pancreatitis, and chronic pancreatitis, can cause pain that is difficult to control. Pain is one of the most debilitating symptoms and demands increasing doses of analgesics and narcotics, as well as the number of hospital admissions, with a direct implication in the costs of medical treatments. To describe the experience with 2 paediatric patients who were subjected to an ultrasound-guided endoscopic celiac ganglion block for difficult pain management, secondary to chronic pancreatitis disease. The first case concerns a 9-year-old male with a diagnosis of chronic pancreatitis, and the second case is a 12-year-old female who developed episodes of intermittent acute pancreatitis. Both cases suffered from chronic abdominal pain, which was difficult to control with stronger painkillers, such as opioids. The pain decreased after patients were subjected to an ultrasound-guided endoscopic celiac ganglion block. This technique showed that both patients obtained satisfactory pain relief, with significant improvements in general symptomatology and the stopping of almost all analgesic medication. The authors suggest that celiac ganglion block must be considered, and implemented early before the usual complications, such as a consumption syndrome that is frequent in paediatric patients with chronic pancreatitis. Copyright © 2016 Academia Mexicana de Cirugía A.C. Publicado por Masson Doyma México S.A. All rights reserved.

  14. Spatial and frequency-based super-resolution of ultrasound images.

    PubMed

    Wu, Mon-Ju; Karls, Joseph; Duenwald-Kuehl, Sarah; Vanderby, Ray; Sethares, William

    2014-07-01

    Modern ultrasound systems can output video images containing more spatial and temporal information than still images. Super-resolution techniques can exploit additional information but face two challenges: image registration and complex motion. In addition, information from multiple available frequencies is unexploited. Herein, we utilised these information sources to create better ultrasound images and videos, extending existing technologies for image capture. Spatial and frequency-based super-resolution processing using multiple motion estimation and frequency combination was applied to ultrasound videos of deforming models. Processed images are larger, have greater clarity and detail, and less variability in intensity between frames. Significantly, strain measurements are more accurate and precise than those from raw videos, and have a higher contrast ratio between 'tumour' and 'surrounding tissue' in a phantom model. We attribute improvements to reduced noise and increased resolution in processed images. Our methods can significantly improve quantitative and qualitative assessments of ultrasound images when compared assessments of standard images.

  15. A review of viscosupplementation for osteoarthritis of the hip and a description of an ultrasound-guided hip injection technique.

    PubMed

    Mulvaney, Sean W

    2009-01-01

    Viscosupplementation of the hip for symptomatic osteoarthritis appears to be safe and effective in more than 25 yr of use in Europe. More than 11 studies suggest that viscosupplementation in the hip is as effective as viscosupplementation in the knee. It appears to be a safe and reasonable alternative to nonsteroidal antiinflammatory drugs or intra-articular steroids for the treatment of osteoarthritis pain. Viscosupplementation in the hip may delay the need for hip replacement surgery. Viscosupplementation in the hip appears to work better in patients with fewer radiographic changes of osteoarthritis. Placement of viscosupplement in the hip under real-time ultrasound or fluoroscopic guidance is safe and well tolerated. Hip joint communication with the iliopsoas bursa may be a factor in studies of the effectiveness of viscosupplementation in the hip.

  16. Ultrasound -- Vascular

    MedlinePlus

    ... ultrasound uses sound waves to evaluate the body’s circulatory system and help identify blockages in the arteries and ... is a useful way of evaluating the body's circulatory system. Vascular ultrasound is performed to: help monitor the ...

  17. Abdominal ultrasound

    MedlinePlus

    ... Kidney - blood and urine flow Abdominal ultrasound References Chen L. Abdominal ultrasound imaging. In: Sahani DV, Samir ... the Health on the Net Foundation (www.hon.ch). The information provided herein should not be used ...

  18. Ultrasound -- Pelvis

    MedlinePlus Videos and Cool Tools

    ... needles are used to extract a sample of cells from organs for laboratory testing. Doppler ultrasound images ... ultrasound, measures the direction and speed of blood cells as they move through vessels. The movement of ...

  19. Ultrasound -- Vascular

    MedlinePlus

    ... ultrasound uses sound waves to evaluate the body’s circulatory system and help identify blockages and detect blood clots. ... is a useful way of evaluating the body's circulatory system. Vascular ultrasound is performed to: help monitor the ...

  20. Ultrasound contrast agents for ultrasound molecular imaging.

    PubMed

    Tranquart, F; Arditi, M; Bettinger, T; Frinking, P; Hyvelin, J M; Nunn, A; Pochon, S; Tardy, I

    2014-11-01

    Ultrasound is a real-time imaging technique which is widely used in many clinical applications for its capacity to provide anatomic information with high spatial and temporal resolution. The advent of ultrasound contrast agents in combination with contrast-specific imaging modes has given access to perfusion assessments at an organ level, leading to an improved diagnostic accuracy. More recently, the development of biologically-targeted ultrasound contrast agents has expanded the role of ultrasound even further into molecular imaging applications. Ultrasound molecular imaging can be used to visualize the expression of intravascular markers, and to assess their local presence over time and/or during therapeutic treatment. Major applications are in the field of inflammation and neoangiogenesis due to the strictly intravascular presence of microbubbles. Various technologies have been investigated for attaching the targeting moiety to the shell from simple biotin-avidin constructs to more elaborated insertion within the shell through attachment to PEG residues. This important improvement has allowed a clinical translation of initial pre-clinical investigations, opening the way for an early detection and an accurate characterization of lesions in patients. The combination of anatomic, functional and molecular information/data provided by contrast ultrasound is a powerful tool which is still in its infancy due to the lack of agents suitable for clinical use. The advantages of ultrasound techniques combined with the molecular signature of lesions will represent a significant advance in imaging in the field of personalized medicine. © Georg Thieme Verlag KG Stuttgart · New York.

  1. Carotid Ultrasound

    MedlinePlus

    ... this page from the NHLBI on Twitter. Carotid Ultrasound Also known as carotid duplex. Carotid ultrasound is a painless imaging test that uses high- ... of your carotid arteries. This test uses an ultrasound machine, which includes a computer, a screen, and ...

  2. Slow-pull and different conventional suction techniques in endoscopic ultrasound-guided fine-needle aspiration of pancreatic solid lesions using 22-gauge needles

    PubMed Central

    Chen, Jia-Ying; Ding, Qing-Yu; Lv, Yang; Guo, Wen; Zhi, Fa-Chao; Liu, Si-De; Cheng, Tian-Ming

    2016-01-01

    AIM To evaluate the cytological diagnostic capacity and sample quality of the slow-pull technique and compare them with different suction techniques. METHODS From July 2010 to December 2015, 102 patients with pancreatic solid lesions who underwent endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) with 22-gauge needles were retrospectively evaluated. EUS-FNA diagnosis was based on a cytological examination, and final diagnosis was based on a comprehensive standard of cytological diagnosis, surgical pathology and clinical or imaging follow-up. Cytological specimens were characterized for cellularity and blood contamination. The cytological diagnostic capacity and sample quality of the slow-pull technique and suction techniques with 5-mL/10-mL/20-mL syringes were analyzed. RESULTS Of all of the EUS-FNA procedures, the slow-pull technique and suction techniques with 5-mL/10-mL/20-mL syringes were used in 31, 19, 34 and 18 procedures, respectively. There were significant differences between these four suction techniques in terms of cytological diagnostic accuracy (90.3% vs 63.2% vs 58.8% vs 55.6%, P = 0.019), sensitivity (88.2% vs 41.7% vs 40.0% vs 36.4%, P = 0.009) and blood contamination (score ≥ 2 for 29.0% vs 52.6% vs 70.6% vs 72.2%, P = 0.003). The accuracy and sensitivity of the slow-pull technique were significantly higher than those of the suction techniques using 5-mL (P = 0.03, P = 0.014), 10-mL (P = 0.005; P = 0.006) and 20-mL syringes (P = 0.01, P = 0.01). Blood contamination was significantly lower in the slow-pull technique than in the suction techniques with 10-mL (P = 0.001) and 20-mL syringes (P = 0.007). CONCLUSION The slow-pull technique may increase the cytological diagnostic accuracy and sensitivity with slight blood contamination during EUS-FNA when using 22-gauge needles for solid pancreatic masses. PMID:27818594

  3. Slow-pull and different conventional suction techniques in endoscopic ultrasound-guided fine-needle aspiration of pancreatic solid lesions using 22-gauge needles.

    PubMed

    Chen, Jia-Ying; Ding, Qing-Yu; Lv, Yang; Guo, Wen; Zhi, Fa-Chao; Liu, Si-De; Cheng, Tian-Ming

    2016-10-21

    To evaluate the cytological diagnostic capacity and sample quality of the slow-pull technique and compare them with different suction techniques. From July 2010 to December 2015, 102 patients with pancreatic solid lesions who underwent endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) with 22-gauge needles were retrospectively evaluated. EUS-FNA diagnosis was based on a cytological examination, and final diagnosis was based on a comprehensive standard of cytological diagnosis, surgical pathology and clinical or imaging follow-up. Cytological specimens were characterized for cellularity and blood contamination. The cytological diagnostic capacity and sample quality of the slow-pull technique and suction techniques with 5-mL/10-mL/20-mL syringes were analyzed. Of all of the EUS-FNA procedures, the slow-pull technique and suction techniques with 5-mL/10-mL/20-mL syringes were used in 31, 19, 34 and 18 procedures, respectively. There were significant differences between these four suction techniques in terms of cytological diagnostic accuracy (90.3% vs 63.2% vs 58.8% vs 55.6%, P = 0.019), sensitivity (88.2% vs 41.7% vs 40.0% vs 36.4%, P = 0.009) and blood contamination (score ≥ 2 for 29.0% vs 52.6% vs 70.6% vs 72.2%, P = 0.003). The accuracy and sensitivity of the slow-pull technique were significantly higher than those of the suction techniques using 5-mL (P = 0.03, P = 0.014), 10-mL (P = 0.005; P = 0.006) and 20-mL syringes (P = 0.01, P = 0.01). Blood contamination was significantly lower in the slow-pull technique than in the suction techniques with 10-mL (P = 0.001) and 20-mL syringes (P = 0.007). The slow-pull technique may increase the cytological diagnostic accuracy and sensitivity with slight blood contamination during EUS-FNA when using 22-gauge needles for solid pancreatic masses.

  4. Role of ultrasound in the understanding and management of vasculitis

    PubMed Central

    2014-01-01

    Vasculitis is characterized by a circumferential vessel-wall thickening (‘halo’), which can be visualized by modern imaging techniques. In particular, the resolution of ultrasound has increased to 0.1 mm. Ultrasound detects abnormalities that are pathognomonic even in arteries with a diameter below 1 mm. It is particularly helpful in the diagnosis of large-vessel vasculitides, such as classic temporal arteritis, large-vessel giant-cell arteritis (GCA), Takayasu arteritis and idiopathic aortitis. Echocardiography is important for determining cardiac involvement in Takayasu arteritis and also for examining the coronary arteries of children with suspected Kawasaki disease, which is a medium-vessel vasculitis. In small vessel vasculitides ultrasound has only a role for determining the distribution or organ involvement. Fast-track clinics for the diagnosis of GCA help to initiate treatment before complications such as blindness occur; patients receive appointments within 24 h in these clinics. Clinical examination and ultrasound of temporal and axillary arteries are performed by an experienced rheumatologist. In most cases this is able to determine if GCA is present. Temporal artery biopsy can be still carried out in ambivalent cases. The wall swelling of temporal arteries disappears after 2–3 weeks of glucocorticoid treatment. After 3 days of treatment, diagnosis becomes more difficult with ultrasound in some cases. In larger arteries, such as the axillary arteries, wall thickening disappears within months. It tends to be darker (more hypoechoic) in acute disease because of oedema. PMID:24688604

  5. Contrast-enhanced ultrasound for imaging of adrenal masses.

    PubMed

    Dietrich, C F; Ignee, A; Barreiros, A P; Schreiber-Dietrich, D; Sienz, M; Bojunga, J; Braden, B

    2010-04-01

    The number of incidentally discovered adrenal masses is growing due to the increased use of modern high-resolution imaging techniques. However, the characterization and differentiation of benign and malignant adrenal lesions is challenging. This study aimed to evaluate contrast-enhanced ultrasound for the characterization of adrenal masses. We studied 58 patients with adrenal masses detected with computed tomography, magnetic resonance imaging, or ultrasound. 7 patients had bilateral adrenal lesions. Contrast-enhanced ultrasound was performed using high-resolution ultrasound (3.5 - 7 MHz) and intravenous injection of 2.4 ml SonoVue. The contrast enhancement pattern of all adrenal lesions was documented. The 18 malignant adrenal tumors were significantly larger at the time of diagnosis compared to the 40 benign lesions (p < 0.03). The majority of benign adrenal lesions (37 / 40) had a nonspecific type of contrast enhancement (24 / 40) or a peripheral to central contrast filling (13 / 40) described as the iris phenomenon. Similar findings were observed in malignant adrenal tumors: most malignant lesions also showed nonspecific (6 / 18) or peripheral to central contrast filling (9 / 18). Peripheral to central contrast filling had 50 % sensitivity (26 - 74 %) and 68 % specificity (51 - 81 %) for indicating malignancy. Contrast-enhanced ultrasound facilitates the visualization of vascularization even in small adrenal masses, but it does not help to distinguish malignant and benign lesions. Georg Thieme Verlag KG Stuttgart . New York.

  6. Medical ultrasound systems.

    PubMed

    Powers, Jeff; Kremkau, Frederick

    2011-08-06

    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.

  7. Ultrasound tracking for intra-fractional motion compensation in radiation therapy.

    PubMed

    Schwaab, J; Prall, M; Sarti, C; Kaderka, R; Bert, C; Kurz, C; Parodi, K; Günther, M; Jenne, J

    2014-07-01

    Modern techniques as ion beam therapy or 4D imaging require precise target position information. However, target motion particularly in the abdomen due to respiration or patient movement is still a challenge and demands methods that detect and compensate this motion. Ultrasound represents a non-invasive, dose-free and model-independent alternative to fluoroscopy, respiration belt or optical tracking of the patient surface. Thus, ultrasound based motion tracking was integrated into irradiation with actively scanned heavy ions. In a first in vitro experiment, the ultrasound tracking system was used to compensate diverse sinusoidal target motions in two dimensions. A time delay of ∼200 ms between target motion and reported position data was compensated by a prediction algorithm (artificial neural network). The irradiated films proved feasibility of the proposed method. Furthermore, a practicable and reliable calibration workflow was developed to enable the transformation of ultrasound tracking data to the coordinates of the treatment delivery or imaging system - even if the ultrasound probe moves due to respiration. A first proof of principle experiment was performed during time-resolved positron emission tomography (4DPET) to test the calibration workflow and to show the accuracy of an ultrasound based motion tracking in vitro. The results showed that optical ultrasound tracking can reach acceptable accuracies and encourage further research.

  8. Ultrasound-guided sciatic nerve block in overweight and obese patients: a randomized comparison of performance time between the infragluteal and subgluteal space techniques.

    PubMed

    Abdallah, Faraj W; Chan, Vincent W; Koshkin, Arkadiy; Abbas, Sherif; Brull, Richard

    2013-01-01

    Despite ultrasound (US) guidance, sciatic nerve block (SNB) remains among the least performed peripheral blocks. By targeting the tissue plane between the gluteus maximus and quadratus femoris muscles, the US-guided subgluteal space technique may facilitate the performance of US-guided SNB. We aimed to evaluate whether the subgluteal space technique shortens SNB performance time in overweight and obese patients compared with the conventional infragluteal technique. Overweight and obese patients (body mass index, > 25 kg m ) undergoing US-guided SNB for knee arthroplasty received 30 mL admixture (1:2 lidocaine 2%; bupivacaine 0.5% with 1:200,000 epinephrine) in the tissue plane between the gluteus maximus and quadratus femoris (subgluteal space group) or around the sciatic nerve at the infragluteal level (infragluteal group). All patients received spinal anesthesia, continuous femoral nerve block, and postoperative multimodal analgesia. The primary outcome was SNB performance time defined as the time interval between placement of the US transducer on skin, and needle withdrawal after injection. Number of needle passes, procedural pain, SNB-related complications, SNB success, postoperative pain, and opioid consumption were also assessed. Twenty-seven patients were assessed (subgluteal space, 14; infragluteal, 13). Mean SNB performance time was 4.4 minutes (95% confidence interval, 3.7-5.0) for the subgluteal space group and 9.0 minutes (95% confidence interval, 7.7-10.3) for the infragluteal group (P < 0.0001). Number of needle passes and procedural pain scores were lower in the subgluteal space group. There were no differences in SNB success or analgesic outcomes. The subgluteal space technique may be performed 50% faster, with no detectable differences in block success and analgesic efficacy, compared with the infragluteal technique for US-guided SNB in overweight and obese patients receiving multimodal analgesia. Injection of local anesthetics along tissue

  9. Comparative Effectiveness of Two Ultrasound-Guided Regional Block Techniques for Surgical Anesthesia in Open Unilateral Inguinal Hernia Repair.

    PubMed

    Steffel, Lauren; Kim, T Edward; Howard, Steven K; Ly, Daphne P; Kou, Alex; King, Robert; Mariano, Edward R

    2016-01-01

    Transversus abdominis plane (TAP) and ilioinguinal/iliohypogastric (II/IH) nerve blocks have been described as analgesic adjuncts for inguinal hernia repair, but the efficacy of these techniques in providing intraoperative anesthesia, either individually or together, is not known. We designed this retrospective cohort study to test the hypothesis that combining TAP and II/IH nerve blocks ("double TAP" technique) results in greater accordance between the preoperative anesthetic plan and actual anesthetic technique provided when compared to TAP alone. Based on this study, double TAP may be preferred for patients undergoing open inguinal hernia repair who wish to avoid general anesthesia.

  10. Optimized Retroperitoneoscopic Excision of Large (>25 cm) Adult Polycystic Kidneys Using 3-Dimensional Image Reconstruction and Preresection Ultrasound-Guided Aspiration: Technique and Early Outcomes.

    PubMed

    Li, Chunhui; Kennedy, Chris; Nabi, Ghulam

    2015-12-01

    Laparoscopic excision of large polycystic kidneys remains a challenging procedure. Most of the literature describes transperitoneal approaches. Alterations in anatomy due to size of kidneys can make vascular and hilar control difficult. Retroperitoneal access with direct control of pedicle avoids risks without dissection for structures anterior to the kidneys. The technique of retroperitoneoscopic excision of massively enlarged kidneys is described with early outcomes. Patient DICOM images of kidneys were segmented and reconstructed for 3-dimensional visualization before surgery. Total excision of large polycystic kidneys was performed in 10 patients (11 procedures). After creation of retroperitoneal space, renal pedicle dissection was started with the incision of thinned out Gerota's fascia. Occasionally aspiration of large cysts using ultrasound assistance created space for precise dissection. Following control of vascular pedicle under laparoscopic vision, further aspiration of cysts was accomplished with the help of 3-dimensional reconstructed kidney. Postaspiration, remaining renal specimen was extracted through a small incision using an endobag or as an intact specimen. The operative time was between 180 and 240 minutes (median 200 minutes). Intraoperative blood loss was 100 to 300 mL (median 175 mL). Median time to control pedicle was 12 minutes (range 10-25 minutes). The postoperative periods were uneventful, except for blockage of arteriovenous fistula in 1 patient. Mean hospital stay was 7 days (range 6-14 days). The retroperitoneasocopic approach to large polycystic kidneys under the guidance of 3-dimensional image reconstruction, occasionally with the assistance of ultrasound aspiration is technically feasible, safe, with good perioperative outcomes. It facilitates early control of vascular pedicle with minimal risk of intraoperative bleeding. © The Author(s) 2015.

  11. Overview on modern approaches to speed up protein identification workflows relying on enzymatic cleavage and mass spectrometry-based techniques.

    PubMed

    Capelo, J L; Carreira, R; Diniz, M; Fernandes, L; Galesio, M; Lodeiro, C; Santos, H M; Vale, G

    2009-09-21

    Recent tools addressed to accelerate the different steps of the sample treatment for protein identification in modern workflows are reviewed and critically commented in this manuscript. Heating, microspin columns, ultrasonic energy, high pressure, infrared energy, microwave energy, alternating electric fields and microreactors are outlined as useful tools that can be used to accelerate all or some of the following steps for in-gel or in-liquid based approaches for protein identification: (i) protein dissolution/denaturation, (ii) protein reduction, (iii) protein alkylation and (iv) protein digestion. The advantages and drawbacks, along with the main differences among the different tools are also commented. Future prospects for hyphenation of methods are also discussed. Researchers are informed also in this work regarding the main problems to be found when implementing any of the above mentioned methods.

  12. Standards of the Polish Ultrasound Society - update. The liver, gallbladder and bile ducts examinations.

    PubMed

    Walas, Maria Krystyna; Skoczylas, Krzysztof; Gierbliński, Ireneusz

    2012-12-01

    Ultrasonography, which usually constitutes an initial imaging method of the gallbladder, liver and bile ducts diseases, allows for final diagnosis or determines another diagnostic step. The continuously progressing technological advancement forces to broaden the indications for ultrasound diagnostics and enables easier and more precise imaging of the tested structures. Performing the examination in accordance with current standards allows for the optimization of the sensitivity and specificity parameters of ultrasound examinations in the diagnosis of the liver, gallbladder and bile ducts pathologies as well as minimizes the probability of error-making. This article presents a recommended liver, gallbladder and bile ducts ultrasound technique which indicates an optimal positioning of the patient for the exam as well as the sites of the ultrasound transducer application. Minimum technical parameters of the apparatus have been specified with respect to the requirements of modern ultrasound techniques which enable imaging with the use of contrast agents and elastography. Furthermore, the article proposes a standard exam description containing essential patient-related data and provides required ultrasound evaluation parameters for the tested organs. Attention has been drawn to the appropriate manner of preparing the patient for the examination and the features of the tested structures have been presented. The article also contains a brief description of the liver, gallbladder and bile ducts diseases which are most often diagnosed by ultrasound examinations. Moreover, the use of elastography as well as contrast-enhanced examinations in the diagnostics of fibrosis and focal changes in the liver have been discussed. This article has been prepared on the basis of the Ultrasound Examination Standards of the Polish Ultrasound Society (2011) and updated with reference to the latest findings in pertinent literature.

  13. Standards of the Polish Ultrasound Society – update. The liver, gallbladder and bile ducts examinations

    PubMed Central

    Walas, Maria Krystyna; Gierbliński, Ireneusz

    2012-01-01

    Ultrasonography, which usually constitutes an initial imaging method of the gallbladder, liver and bile ducts diseases, allows for final diagnosis or determines another diagnostic step. The continuously progressing technological advancement forces to broaden the indications for ultrasound diagnostics and enables easier and more precise imaging of the tested structures. Performing the examination in accordance with current standards allows for the optimization of the sensitivity and specificity parameters of ultrasound examinations in the diagnosis of the liver, gallbladder and bile ducts pathologies as well as minimizes the probability of error-making. This article presents a recommended liver, gallbladder and bile ducts ultrasound technique which indicates an optimal positioning of the patient for the exam as well as the sites of the ultrasound transducer application. Minimum technical parameters of the apparatus have been specified with respect to the requirements of modern ultrasound techniques which enable imaging with the use of contrast agents and elastography. Furthermore, the article proposes a standard exam description containing essential patient-related data and provides required ultrasound evaluation parameters for the tested organs. Attention has been drawn to the appropriate manner of preparing the patient for the examination and the features of the tested structures have been presented. The article also contains a brief description of the liver, gallbladder and bile ducts diseases which are most often diagnosed by ultrasound examinations. Moreover, the use of elastography as well as contrast-enhanced examinations in the diagnostics of fibrosis and focal changes in the liver have been discussed. This article has been prepared on the basis of the Ultrasound Examination Standards of the Polish Ultrasound Society (2011) and updated with reference to the latest findings in pertinent literature. PMID:26673807

  14. Randomized controlled trial comparing the effectiveness of the ultrasound-guided galvanic electrolysis technique (USGET) versus conventional electro-physiotherapeutic treatment on patellar tendinopathy.

    PubMed

    Abat, F; Sánchez-Sánchez, J L; Martín-Nogueras, A M; Calvo-Arenillas, J I; Yajeya, J; Méndez-Sánchez, R; Monllau, J C; Gelber, P E

    2016-12-01

    Patellar tendinopathy has a high prevalence rate among athletes. Different therapeutic options can be found in the current literature, but none of them has been clearly established as the gold standard. The purpose of this study is to compare, in a randomized controlled trial, the clinical efficacy of eccentric exercise combined with either an ultrasound-guided galvanic electrolysis technique (USGET) or conventional electrophysiotherapy to treat patellar tendinopathy. Sixty patients diagnosed with patellar tendinopathy were randomized into two groups. Group 1 (n = 30) received electrophysiotherapy treatment consisting of ultrasound, laser and interferential current techniques. Group 2 (n = 30) received USGET. Both groups did the same standardized eccentric exercise program. Periodic assessments of the subjects were carried out with the Victorian Institute of Sport Assessment-Patella (VISA-P) score. An analysis of means and a survival study were performed. There were statistically significant differences in the VISA-P between the baseline and final follow-up in each treatment group. Group 1 (conventional electrophysiotherapy) went from 52.5 ± 18.8 to 61.9 ± 13.7 (in VISA-P < 90 subgroup) and from 69.1 ± 9.1 to 95.2 ± 2.5 (in VISA-P > 90 subgroup). Group 2 (USGET) went from 51.4 ± 17.9 to 63.3 ± 14.3 (in VISA-P < 90 subgroup) and from 66.3 ± 13.1 to 97.1 ± 1.7 (in VISA-P > 90 subgroup). There were statistically significant correlations between the baseline and final score in the VISA-P > 90 subjects upon completing the study but no statistically significant correlations between subjects with VISA-P < 90. The mean number of sessions applied was 22.6 ± 2.5 in Group 1 and 3.2 ± 0.9 in Group 2. The success probability in Group 1 was 36.1% versus 72.4% in Group 2. The difference was statistically significant. The results obtained with the combination of USGET and eccentric exercise reported

  15. Ultrasound-guided synovial biopsy

    PubMed Central

    Sitt, Jacqueline C M; Wong, Priscilla

    2016-01-01

    Ultrasound-guided needle biopsy of synovium is an increasingly performed procedure with a high diagnostic yield. In this review, we discuss the normal synovium, as well as the indications, technique, tissue handling and clinical applications of ultrasound-guided synovial biopsy. PMID:26581578

  16. Xampling in ultrasound imaging

    NASA Astrophysics Data System (ADS)

    Wagner, Noam; Eldar, Yonina C.; Feuer, Arie; Danin, Gilad; Friedman, Zvi

    2011-03-01

    Recent developments of new medical treatment techniques put challenging demands on ultrasound imaging systems in terms of both image quality and raw data size. Traditional sampling methods result in very large amounts of data, thus, increasing demands on processing hardware and limiting the flexibility in the postprocessing stages. In this paper, we apply Compressed Sensing (CS) techniques to analog ultrasound signals, following the recently developed Xampling framework. The result is a system with significantly reduced sampling rates which, in turn, means significantly reduced data size while maintaining the quality of the resulting images.

  17. Application of ultrasound irradiation on sol-gel technique for corrosion protection of Al65Cu20Fe15 alloy powder

    NASA Astrophysics Data System (ADS)

    Liang, Bo; Zhang, Baoyan; Wang, Guodong; Li, Di; Zhang, Xiaoming

    2013-11-01

    Al65Cu20Fe15 alloy powder was firstly encapsulated by the conventional sol-gel technique utilizing tetraethoxysilane (TEOS) as the precursor in order to improve its corrosion resistance. The optimization was based on nine well-planned orthogonal experiments (L9 (34)). Four main factors in the encapsulation process (i.e. reaction temperature, ethylenediamine concentration, TEOS concentration and feeding method) were investigated. According to the visual analyses of the result, the optimum condition was obtained. Based on the optimal condition in the conventional sol-gel technique, the encapsulation process was then conducted under ultrasonic irradiation. The effects of ultrasound amplitude and irradiation time on the encapsulation process were also studied. FTIR, XRD, SEM, DLS and EDS were also used to characterize the resulting sample. Finally, the corrosion inhibition efficiency of encapsulated powder attained 99.3% in the acidic condition of pH 1, and the average grain size (d50) of the encapsulated powder was just 4.8% larger than that of the raw powder, implying that there was a thin silica film on the surface of powder.

  18. Real-time ultrasound-guided fine needle cytology of the thyroid gland by capillary action. A modified technique without aspiration.

    PubMed

    Gkeli, M G; Daskalopoulou, D

    2011-01-01

    To present a modified technique of real-time (Rt) ultrasound-guided (Ug) fine-needle (FN) cytology of thyroid nodules without aspiration (RtUg-FNNAC). We retrospectively studied 958 patients with 1202 thyroid nodules referred to our institution between January 2009-January 2010. The efficacy of RtUg-FNNAC was determined by the number of satisfactory specimens that were obtained. Furthermore, we compared the RtUg-FNNAC results with the surgical histological results. All specimens were adequate for diagnosis. Two hundred and twelve (22.1% patients with malignant cytological findings and 20 (2.1%) with indeterminate cytological findings were referred for surgery. All nodules with malignant and indeterminate cytological findings were confirmed histologically. From 20 indeterminate cytological findings 17 (85%) were malignant. From 66 patients with initial benign RtUg-FNNAC who were subjected to surgery the results were true negative in 65 and false negative in 1. Finally, RtUg-FNNAC was true positive in 229 cases and false positive in 3. The overall sensitivity, specificity, positive predictive value and negative predictive value of RtUg-FNNAC were 99.6, 95.6, 98.7 and 98.7%, respectively. Accuracy for the detection of malignancy was 98.7%. RtUg-FNNAC is a technique that combines the benefits of real time US-guidance with those of capillary action sampling, maximizing cellular yield and minimizing bloody artefacts in cytologic examination.

  19. Learning, techniques, and complications of endoscopic ultrasound (EUS)-guided sampling in gastroenterology: European Society of Gastrointestinal Endoscopy (ESGE) Technical Guideline.

    PubMed

    Polkowski, M; Larghi, A; Weynand, B; Boustière, C; Giovannini, M; Pujol, B; Dumonceau, J-M

    2012-02-01

    This article is the second of a two-part publication that expresses the current view of the European Society of Gastrointestinal Endoscopy (ESGE) about endoscopic ultrasound (EUS)-guided sampling, including EUS-guided fine needle aspiration (EUS-FNA) and EUS-guided Trucut biopsy. The first part (the Clinical Guideline) focused on the results obtained with EUS-guided sampling, and the role of this technique in patient management, and made recommendations on circumstances that warrant its use. The current Technical Guideline discusses issues related to learning, techniques, and complications of EUS-guided sampling, and to processing of specimens. Technical issues related to maximizing the diagnostic yield (e.g., rapid on-site cytopathological evaluation, needle diameter, microcore isolation for histopathological examination, and adequate number of needle passes) are discussed and recommendations are made for various settings, including solid and cystic pancreatic lesions, submucosal tumors, and lymph nodes. The target readership for the Clinical Guideline mostly includes gastroenterologists, oncologists, internists, and surgeons while the Technical Guideline should be most useful to endoscopists who perform EUS-guided sampling. A two-page executive summary of evidence statements and recommendations is provided. © Georg Thieme Verlag KG Stuttgart · New York.

  20. 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)

  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. Prospective evaluation of new 22 gauge endoscopic ultrasound core needle using capillary sampling with stylet slow-pull technique for intra-abdominal solid masses.

    PubMed

    Paik, Woo Hyun; Park, Yangsoon; Park, Do Hyun; Hong, Seung-Mo; Lee, Byung Uk; Choi, Jun-Ho; Lee, Sang Soo; Seo, Dong-Wan; Lee, Sung Koo; Kim, Myung-Hwan

    2015-03-01

    The aim of this study was to evaluate the adequacy and diagnostic yield of the histologic core obtained with a 22 G endoscopic ultrasound histology needle using capillary sampling with stylet slow-pull technique without on-site cytopathologist. No standard technique for new EUS histology needle has been established. A total of 125 consecutive patients with intra-abdominal solid masses were enrolled prospectively between October 2011 and March 2013. EUS-guided fine needle biopsy (EUS-FNB) with a 22 G histology needle using capillary sampling with stylet slow-pull technique was performed. A total of 133 EUS-FNB procedures targeting the pancreas, lymph node, retroperitoneal mass, ampulla of Vater, gallbladder, common bile duct, duodenum, and liver were performed in 125 patients. EUS-FNB was technically feasible in all cases, and a visible core was obtained in 128 cases (96%). Histologic core specimens suitable for pathologic assessment were reported in 111 cases (83%). There were no procedure-related adverse events. According to the determinants of malignancy with EUS-FNB, the sensitivity, specificity, positive and negative predictive values, and accuracy were 85%, 98%, 99%, 77%, and 89%, respectively. In addition, histologic architecture with or without immunohistochemical staining of the core biopsy specimens was useful for pathologic confirmation in 101 cases (76%). A 22 G EUS-FNB using capillary sampling with stylet slow-pull technique showed a high diagnostic yield and histologic core acquisition for the histologic diagnosis of various intra-abdominal masses without an on-site cytopathologist. Furthermore, a histologic core with or without immunohistochemical staining was helpful for clinical decision making in 76% of the intra-abdominal solid masses.

  3. Usefulness of modified BRB technique in treatment to ablate uterine fibroids with magnetic resonance image-guided high-intensity focused ultrasound

    PubMed Central

    Jeong, Jae-Heok; Hong, Kil-Pyo; Kim, Yu-Ri; Ha, Jae-Eun

    2017-01-01

    Objective If bowels and other structures are in the pathway of high-intensity focused ultrasound (HIFU) beam during magnetic resonance image-guided HIFU (MRgFUS) therapy, filling to the bladder and the rectum and then emptying the bladder (i.e., the BRB technique) is used to avoid them. A modified BRB technique might be useful method to using a uterine elevator method or by inducing uterus downward traction to lower the position of the uterus. Methods A total of 156 patients who had undergone MRgFUS surgery treatment for uterine fibroids from March 2015 to February 2016 were included in this retrospective study. Of the 156 patients, 40 were treated using a uterine elevator while 29 were treated using downward traction of uterus. HIFU was performed using Philips Achieva 1.5 Tesla MR and Sonalleve HIFU system. Results MRgFUS surgery was feasible with modified BRB technique in 69 cases. Using uterine elevator method, the intensity of HIFU for group with antefletxio uteri was significantly lower than that for the group without antefletxio uteri (105.37±17.62 vs. 118.71±26.88 W). The group with downward traction of uterus induced was found to have significantly lower intensity of HIFU compared to the group without downward traction of uterus induced (110.26±22.60 vs. 130.51±27.81 W). Conclusion Modified BRB technique was useful in avoiding bowels and other structures located in HIFU beam pathway during MRgFUS treatment to ablate uterine fibroids. PMID:28217678

  4. Usefulness of modified BRB technique in treatment to ablate uterine fibroids with magnetic resonance image-guided high-intensity focused ultrasound.

    PubMed

    Jeong, Jae-Heok; Hong, Kil-Pyo; Kim, Yu-Ri; Ha, Jae-Eun; Lee, Kyu-Sup

    2017-01-01

    If bowels and other structures are in the pathway of high-intensity focused ultrasound (HIFU) beam during magnetic resonance image-guided HIFU (MRgFUS) therapy, filling to the bladder and the rectum and then emptying the bladder (i.e., the BRB technique) is used to avoid them. A modified BRB technique might be useful method to using a uterine elevator method or by inducing uterus downward traction to lower the position of the uterus. A total of 156 patients who had undergone MRgFUS surgery treatment for uterine fibroids from March 2015 to February 2016 were included in this retrospective study. Of the 156 patients, 40 were treated using a uterine elevator while 29 were treated using downward traction of uterus. HIFU was performed using Philips Achieva 1.5 Tesla MR and Sonalleve HIFU system. MRgFUS surgery was feasible with modified BRB technique in 69 cases. Using uterine elevator method, the intensity of HIFU for group with antefletxio uteri was significantly lower than that for the group without antefletxio uteri (105.37±17.62 vs. 118.71±26.88 W). The group with downward traction of uterus induced was found to have significantly lower intensity of HIFU compared to the group without downward traction of uterus induced (110.26±22.60 vs. 130.51±27.81 W). Modified BRB technique was useful in avoiding bowels and other structures located in HIFU beam pathway during MRgFUS treatment to ablate uterine fibroids.

  5. Interventional ultrasound

    SciTech Connect

    Holm, H.H.; Kristensen, J.K.

    1985-01-01

    This book discusses: Introduction to interventional ultrasound/handling of aspirated material/general principles of fine needle aspiration cytology/procedure and principles in ultrasonically guided puncture/puncture of focal liver lesions/intraoperative puncture of the liver guided by ultrasound/Interventional ultrasound in cancer therapy/Interventional echocardiography/Fine-needle aspiration biopsy: Are there any risks./Puncture of renal mass lesions/Intrauterine needle diagnosis/Percutaneous nephrolithotomy.

  6. Why Anesthesiologists Must Incorporate Focused Cardiac Ultrasound Into Daily Practice.

    PubMed

    Coker, Bradley J; Zimmerman, Josh M

    2017-03-01

    The size, availability, cost, and quality of modern ultrasound devices have, for the first time in modern medicine, enabled point-of-care ultrasound by the noncardiologist physician. The appropriate application of focused cardiac ultrasound (FoCUS) by anesthesiologists has the potential to alter management and affect outcomes for a wide range of patients. In this article, the indications, benefits, and limitations of FoCUS are described. The training and equipment required to perform FoCUS are also discussed.

  7. Magnetic resonance imaging of the brain in children with headache: the clinical relevance with modern acquisition techniques.

    PubMed

    Streibert, Phillipp Fridolin; Piroth, Werner; Mansour, Michael; Haage, Patrick; Langer, Thorsten; Borusiak, Peter

    2011-12-01

    The aim of this study was to evaluate the frequency of abnormal findings in magnetic resonance imaging (MRI) in children with headache, the clinical relevance of these findings, and whether more sophisticated technologies also result in more relevant abnormal findings. The MRIs of 1004 children with age ranging from 1 to 17 years were retrospectively analyzed. Children who were investigated with established sequences (n = 419) were compared with those examined with state-of-the-art MRI acquisition technology (n = 585). In 216/1004 investigations, MRI was performed because of headache (74/216 with established sequences, 142/216 with state-of-the-art acquisition technology). In 114/216 (52.8%) patients with headache, the MRI was abnormal with relevant findings in 23/114 patients and findings without clinical relevance in 91/114 children. A higher incidence of abnormal findings than in previous reports was found but there was only limited clinical gain of information using modern sequences in children with headache.

  8. Physiological actions of preservative agents: prospective of use of modern microbiological techniques in assessing microbial behaviour in food preservation.

    PubMed

    Brul, Stanley; Coote, Peter; Oomes, Suus; Mensonides, Femke; Hellingwerf, Klaas; Klis, Frans

    2002-11-15

    In this mini-review, various aspects of homeostasis of microbial cells and its perturbation by antimicrobial agents will be discussed. First, outlining the position that the physiological studies on microbial behaviour using the modern molecular tools should have in food science sets the scene for the studies. Subsequently, the advent of functional genomics is discussed that allows full coverage of cellular reactions at unprecedented levels. Examples of weak organic acid resistance, the stress response against natural antimicrobial agents and responses against physicochemical factors show how we can now "open the black box" that microbes are, look inside and begin to understand how different cellular signalling cables are wired together. Using the analogy with machines, it will be indicated how the use of various signalling systems depends on the availability of substrates "fuel" to let the systems act in the context of the minimum energetic requirement cells have to let their housekeeping systems run. The outlook illustrates how new insights might be used to device knowledge-based rather than empirical combinations of preservation systems and how risk assessment models might be deviced that link the mechanistic insight to risk distributions of events in food manufacturing.

  9. Comparison of ultrasound and nerve stimulation techniques for interscalene brachial plexus block for shoulder surgery in a residency training environment: a randomized, controlled, observer-blinded trial.

    PubMed

    Thomas, Leslie C; Graham, Sean K; Osteen, Kristie D; Porter, Heather Scuderi; Nossaman, Bobby D

    2011-01-01

    The ability to provide adequate intraoperative anesthesia and postoperative analgesia for orthopedic shoulder surgery continues to be a procedural challenge. Anesthesiology training programs constantly balance the time needed for procedural education versus associated costs. The administration of brachial plexus anesthesia can be facilitated through nerve stimulation or by ultrasound guidance. The benefits of using a nerve stimulator include a high incidence of success and less cost when compared to ultrasonography. Recent studies with ultrasonography suggest high success rates and decreased procedural times, but less is known about the comparison of these procedural times in training programs. We conducted a prospective, randomized, observer-blinded study with inexperienced clinical anesthesia (CA) residents-CA-1 to CA-3-to compare differences in these 2 guidance techniques in patients undergoing interscalene brachial plexus block for orthopedic surgery. In this study, 41 patients scheduled for orthopedic shoulder surgery were randomly assigned to receive an interscalene brachial plexus block guided by either ultrasound (US group) or nerve stimulation (NS group). Preoperative analgesics and sedatives were controlled in both groups. The US group required significantly less time to conduct the block (4.3 ± 1.5 minutes) than the NS group (10 ± 1.5 minutes), P  =  .009. Moreover, the US group achieved a significantly faster onset of sensory block (US group, 12 ± 2 minutes; NS group, 19 ± 2 minutes; P  =  .02) and motor block (US group, 13.5 ± 2.3 minutes; NS group, 20.2 ± 2.1 minutes; P  =  .03). Success rates were high for both techniques and were not statistically different (US group, 95%; NS group, 91%). No differences were found in operative times, postoperative pain scores, need for rescue analgesics, or incidences of perioperative or postdischarge side effects. On the basis of our results with inexperienced residents, we

  10. Intra-channel stent release technique for fluoroless endoscopic ultrasound-guided lumen-apposing metal stent placement: changing the paradigm

    PubMed Central

    Anderloni, Andrea; Attili, Fabia; Carrara, Silvia; Galasso, Domenico; Di Leo, Milena; Costamagna, Guido; Repici, Alessandro; Kunda, Rastislav; Larghi, Alberto

    2017-01-01

    Background Recently, a novel lumen-apposing fully covered self-expanding metal stent (LA-FCSEMS) mounted on an electrocautery-enhanced delivery system has been developed to perform endoscopic ultrasound (EUS)-guided transluminal drainage. From early experience, however, release of the proximal flange of the stent has mostly been done using endoscopic view guidance to ensure proper positioning. Aim We describe a new technique that we have named the Intra-Channel Stent Release Technique (ICSRT) to perform stent placement under complete EUS control, without the use of either fluoroscopic or endoscopic views. Material and methods Data on all consecutive patients who underwent EUS-guided drainage using the new ICSRT between June 2014 and April 2016 were retrospectively retrieved from two institution databases. All EUS procedures were performed by experienced endoscopists with the patient under conscious or deep sedation. The total procedure and stent deployment time, and adverse events related to stent positioning with the ICSRT were evaluated. Results One hundred consecutive patients (51 women; mean age ± SD, 66 ± 15.2 years, range 34 – 95) underwent EUS-guided transluminal drainage with the Hot AXIOS™ device using the new ICSRT. The procedure was technically successful in all but one patient (1 %). The mean total procedural time was 21.9 minutes (range 7 – 50), while the mean time for stent placement was 3.2 minutes (range 1 – 15). No major adverse events occurred. Discussion The ICSRT has been used to deploy the newly developed lumen-apposing FCSEMS under complete EUS guidance without fluoroscopic and/or endoscopic assistance. The technique appears to be safe and highly effective and should be learned by all interventional endosonographers in order to be able to perform drainage in all clinical scenarios.

  11. Ultrasound spectroscopy

    NASA Astrophysics Data System (ADS)

    Giles, C. L.

    An ultrasound spectrometer was designed, constructed and used to measure the frequency dependence of forward scattered ultrasound from biological specimens. A piezoelectric transducer was continuously tuned through the frequency range of 150 to 400 MHz, producing ultrasound of the same frequency. Pulse modulation of the input signal permitted a frequency resolution of 2 MHz. The received pulse was detected at various temporal positions of its amplitude, thereby allowing measurement of the interference of the scattered and unscattered ultrasound radiation. Because of system nonlinearities all received signals were calibrated with respect to the attenuation of ultrasound in water over the system frequency range. The attenuation of water over the frequency range of 150 to 400 MHz was measured. Forward scattering experiments were performed with both physical objects and biological specimens. Sapphire spheres and plastic cylinders exhibited the expected Mie scattering resonant structure.

  12. Quantitative Study of Elasticity of Rabbit VX2 Liver Tumor with Alternated Cooling and Heating Treatment based on ARFI Ultrasound Imaging Technique

    PubMed Central

    Sun, Di; Wei, Cong; Shen, E.; Ying, Tao; Hu, Bing

    2016-01-01

    Acoustic radiation force impulse (ARFI) ultrasound imaging technique is used to quantitatively evaluate the elasticity of rabbit VX2 liver tumor with alternated cooling and heating treatment (ACHT). ACHT was performed on fifteen VX2 liver tumor models established in fifteen male New Zealand white rabbits with open tumor plant. ARFI was performed on day 0, 1, 7 and 14 after ACHT and shear wave velocity (SWV) in ARFI was recorded to evaluate the elasticity of the treated area. The SWV value of the lesion on day 0, 1, 7 and 14 was 2.33 ± 0.19 m/s, 3.09 ± 0.40 m/s, 2.64 ± 0.37 m/s and 2.26 ± 0.24 m/s, respectively, indicating the treated areas get stiffer on day 1 and then get softer gradually by day. All the difference between adjacent time points was statistically significant. The SWV value of different parts on day 7 approved that the hardness of the treated area is heterogenous: the treated area in the center >the peripheral strip-shaped area >normal liver tissues, consistent with pathological changes. Meanwhile, ARFI combined with conventional US imaging can qualitatively and quantitatively exam the healing process of rabbit VX2 liver tumor after ACHT, and corresponds well to the pathological results. PMID:27381362

  13. The Intravascular Ultrasound Elasticity-Palpography Technique Revisited: A Reliable Tool for the in vivo Detection of Vulnerable Coronary Atherosclerotic Plaques

    PubMed Central

    Deleaval, Flavien; Bouvier, Adeline; Finet, Gérard; Cloutier, Guy; Yazdani, Saami K.; Le Floc’h, Simon; Clarysse, Patrick; Pettigrew, Roderic I.; Ohayon, Jacques

    2016-01-01

    A critical key in detection of vulnerable plaques (VPs) is the quantification of its mechanical properties. From the intravascular ultrasound (IVUS) echogram and strain images, Céspedes et al. (2000) proposed an elasticity-palpography technique (E-PT) to estimate the apparent stress-strain modulus (S-SM) palpogram of the thick endoluminal layer of the arterial wall. However, this approach suffers from major limitations because it was developed for homogeneous, circular and concentric VPs. The present study was therefore designed to improve the E-PT by considering the anatomical shape of the VP. This improved E-PT (IE-PT) was successfully applied to six coronary lesions of patients imaged in vivo with IVUS. Our results demonstrated that the mean relative error of the S-SM decreased from 61.02±9.01% to 15.12±12.57% when considering the IE-PT instead of the E-PT. The accuracy of the S-SM palpograms computed by using the improved theoretical framework was also investigated with regard to noise which may affect prediction of plaque vulnerability. PMID:23727295

  14. Comparison of stroke volume and cardiac output as measured by a single observer using four different ultrasound techniques in six clinically healthy cats.

    PubMed

    Biermann, K; Hungerbühler, S; Kästner, S B R

    2012-12-01

    The aim of this study was to assess agreement and repeatability of four ultrasound methods for measuring stroke volume (SV) and cardiac output (CO) in cats. Measurement of SV and CO was performed by the Teichholz method, the Simpson's method (SM), the area length method (ALM) and a volumetric flow method across the aorta (Trace method). For each method, the coefficient of variation (CV) was calculated and agreement was determined by Bland-Altman analysis. The CV was acceptable (<20%) for all parameters, except for SV and CO obtained by SM (28.8% and 22.4%, respectively) and ALM (21.6% and 22.6%, respectively). Narrow limits of agreement were observed between both planimetric methods (SM and ALM). The Trace method was the most repeatable, followed by the Teichholz method. Despite excellent inter-method agreement, neither of the planimetric methods produced results with adequate repeatability. As the Teichholz and Trace methods were acceptably repeatable, and probably gave the most representative values, they appear to be the most useful methods for the measurement of SV and CO in cats. Further investigations are needed to compare the echocardiographic methods described here with a standard technique such as thermodilution.

  15. Straighten the Back to Sit: Belly-Cultivation Techniques as "Modern Health Methods" in Japan, 1900-1945.

    PubMed

    Wu, Yu-Chuan

    2016-09-01

    In Japan, the first half of the twentieth century saw a remarkable revival of concern with the cultivation of the belly, with a variety of belly-cultivation techniques, particularly breathing exercise and meditative sitting, widely practiced for improving health and treating diseases. This article carefully examines some practitioners' experiences of belly-cultivation practice in attempting to understand its healing effects for them within their life histories and contemporary intellectual, social and cultural contexts. It shows that belly-cultivation practice served as a medium for some practitioners to reflect on and retell their life stories, and that the personal charisma of certain masters and the communities developing around them provided practitioners with a valuable sense of belonging in an increasingly industrialized and urbanized society. Moreover, these belly-cultivation techniques provided an embodied way for some to explore and affirm their sense of self and develop individual identity. While they were increasingly promoted as cultural traditions capable of cultivating national character, they also served as healing practices by inspiring practitioners with a sense of collective identity and purpose. With these analyses, this article sheds light on the complicated meanings of belly-cultivation for practitioners, and provides illustrative examples of the multitude of meanings of the body, bodily cultivation and healing.

  16. Neuromuscular ultrasound of cranial nerves.

    PubMed

    Tawfik, Eman A; Walker, Francis O; Cartwright, Michael S

    2015-04-01

    Ultrasound of cranial nerves is a novel subdomain of neuromuscular ultrasound (NMUS) which may provide additional value in the assessment of cranial nerves in different neuromuscular disorders. Whilst NMUS of peripheral nerves has been studied, NMUS of cranial nerves is considered in its initial stage of research, thus, there is a need to summarize the research results achieved to date. Detailed scanning protocols, which assist in mastery of the techniques, are briefly mentioned in the few reference textbooks available in the field. This review article focuses on ultrasound scanning techniques of the 4 accessible cranial nerves: optic, facial, vagus and spinal accessory nerves. The relevant literatures and potential future applications are discussed.

  17. Techniques and Evaluation From a Cross-Platform Imaging Comparison of Quantitative Ultrasound Parameters in an In Vivo Rodent Fibroadenoma Model

    PubMed Central

    Wirtzfeld, Lauren A.; Nam, Kibo; Labyed, Yassin; Ghoshal, Goutam; Haak, Alexander; Sen-Gupta, Ellora; He, Zhi; Hirtz, Nathaniel R.; Miller, Rita J.; Sarwate, Sandhya; Simpson, Douglas G.; Zagzebski, James A.; Bigelow, Timothy A.; Oelze, Michael L.; Hall, Timothy J.; O’Brien, William D.

    2013-01-01

    This contribution demonstrates that quantitative ultrasound (QUS) capabilities are platform independent, using an in vivo model. Frequency-dependent attenuation estimates, backscatter coefficient, and effective scatterer diameter estimates are shown to be comparable across four different ultrasound imaging systems with varied processing techniques. The backscatter coefficient (BSC) is a fundamental material property from which several QUS parameters are estimated; therefore, consistent BSC estimates among different systems must be demonstrated. This study is an intercomparison of BSC estimates acquired by three research groups (UIUC, UW, ISU) from four in vivo spontaneous rat mammary fibroadenomas using three clinical array systems and a single-element laboratory scanner system. Because of their highly variable backscatter properties, fibroadenomas provided an extreme test case for BSC analysis, and the comparison is across systems for each tumor, not across the highly heterogeneous tumors. RF echo data spanning the 1 to 12 MHz frequency range were acquired in three dimensions from all animals using each system. Each research group processed their RF data independently, and the resulting attenuation, BSC, and effective scatterer diameter (ESD) estimates were compared. The attenuation estimates across all systems showed the same trends and consistently fit the power-law dependence on frequency. BSCs varied among the multiple slices of data acquired by each transducer, with variations between transducers being of a similar magnitude as those from slice to slice. Variation between BSC estimates was assessed via functional signal-to-noise ratios derived from back-scatter data. These functional signal-to-noise ratios indicated that BSC versus frequency variations between systems ranged from negligible compared with the noise level to roughly twice the noise level. The corresponding functional analysis of variance (fANOVA) indicated statistically significant differences

  18. Techniques and evaluation from a cross-platform imaging comparison of quantitative ultrasound parameters in an in vivo rodent fibroadenoma model.

    PubMed

    Wirtzfeld, Lauren A; Nam, Kibo; Labyed, Yassin; Ghoshal, Goutam; Haak, Alexander; Sen-Gupta, Ellora; He, Zhi; Hirtz, Nathaniel R; Miller, Rita J; Sarwate, Sandhya; Simpson, Douglas G; Zagzebski, James A; Bigelow, Timothy A; Oelze, Michael; Hall, Timothy J; O'Brien, William D

    2013-07-01

    This contribution demonstrates that quantitative ultrasound (QUS) capabilities are platform independent, using an in vivo model. Frequency-dependent attenuation estimates, backscatter coefficient, and effective scatterer diameter estimates are shown to be comparable across four different ultrasound imaging systems with varied processing techniques. The backscatter coefficient (BSC) is a fundamental material property from which several QUS parameters are estimated; therefore, consistent BSC estimates among different systems must be demonstrated. This study is an intercomparison of BSC estimates acquired by three research groups (UIUC, UW, ISU) from four in vivo spontaneous rat mammary fibroadenomas using three clinical array systems and a single-element laboratory scanner system. Because of their highly variable backscatter properties, fibroadenomas provided an extreme test case for BSC analysis, and the comparison is across systems for each tumor, not across the highly heterogeneous tumors. RF echo data spanning the 1 to 12 MHz frequency range were acquired in three dimensions from all animals using each system. Each research group processed their RF data independently, and the resulting attenuation, BSC, and effective scatterer diameter (ESD) estimates were compared. The attenuation estimates across all systems showed the same trends and consistently fit the power-law dependence on frequency. BSCs varied among the multiple slices of data acquired by each transducer, with variations between transducers being of a similar magnitude as those from slice to slice. Variation between BSC estimates was assessed via functional signal-to-noise ratios derived from backscatter data. These functional signal-to-noise ratios indicated that BSC versus frequency variations between systems ranged from negligible compared with the noise level to roughly twice the noise level. The corresponding functional analysis of variance (fANOVA) indicated statistically significant differences

  19. Three-dimensional ultrasound imaging.

    PubMed

    Fenster, A; Downey, D B; Cardinal, H N

    2001-05-01

    Ultrasound is an inexpensive and widely used imaging modality for the diagnosis and staging of a number of diseases. In the past two decades, it has benefited from major advances in technology and has become an indispensable imaging modality, due to its flexibility and non-invasive character. In the last decade, research investigators and commercial companies have further advanced ultrasound imaging with the development of 3D ultrasound. This new imaging approach is rapidly achieving widespread use with numerous applications. The major reason for the increase in the use of 3D ultrasound is related to the limitations of 2D viewing of 3D anatomy, using conventional ultrasound. This occurs because: (a) Conventional ultrasound images are 2D, yet the anatomy is 3D, hence the diagnostician must integrate multiple images in his mind. This practice is inefficient, and may lead to variability and incorrect diagnoses. (b) The 2D ultrasound image represents a thin plane at some arbitrary angle in the body. It is difficult to localize the image plane and reproduce it at a later time for follow-up studies. In this review article we describe how 3D ultrasound imaging overcomes these limitations. Specifically, we describe the developments of a number of 3D ultrasound imaging systems using mechanical, free-hand and 2D array scanning techniques. Reconstruction and viewing methods of the 3D images are described with specific examples. Since 3D ultrasound is used to quantify the volume of organs and pathology, the sources of errors in the reconstruction techniques as well as formulae relating design specification to geometric errors are provided. Finally, methods to measure organ volume from the 3D ultrasound images and sources of errors are described.

  20. Determination and identification of synthetic cannabinoids and their metabolites in different matrices by modern analytical techniques - a review.

    PubMed

    Znaleziona, Joanna; Ginterová, Pavlína; Petr, Jan; Ondra, Peter; Válka, Ivo; Ševčík, Juraj; Chrastina, Jan; Maier, Vítězslav

    2015-05-18

    Synthetic cannabinoids have gained popularity due to their easy accessibility and psychoactive effects. Furthermore, they cannot be detected in urine by routine drug monitoring. The wide range of active ingredients in analyzed matrices hinders the development of a standard analytical method for their determination. Moreover, their possible side effects are not well known which increases the danger. This review is focused on the sample preparation and the determination of synthetic cannabinoids in different matrices (serum, urine, herbal blends, oral fluid, hair) published since 2004. The review includes separation and identification techniques, such as thin layer chromatography, gas and liquid chromatography and capillary electrophoresis, mostly coupled with mass spectrometry. The review also includes results by spectral methods like infrared spectroscopy, nuclear magnetic resonance or direct-injection mass spectrometry.

  1. Precision of MRI/ultrasound-fusion biopsy in prostate cancer diagnosis: an ex vivo comparison of alternative biopsy techniques on prostate phantoms.

    PubMed

    Westhoff, N; Siegel, F P; Hausmann, D; Polednik, M; von Hardenberg, J; Michel, M S; Ritter, M

    2017-07-01

    Comparing the accuracy of MRI/ultrasound-guided target-biopsy by transrectal biopsy (TRB) with elastic versus rigid image fusion versus transperineal biopsy (TPB) with rigid image fusion in a standardized setting. Target-biopsy of six differently sized and located lesions was performed on customized CIRS 070L prostate phantoms. Lesions were only MRI-visible. After prior MRI for lesion location, one targeted biopsy per lesion was obtained by TRB with elastic image fusion with Artemis™ (Eigen, USA), TRB with rigid image fusion with real-time virtual sonography (Hitachi, Japan) and TPB with rigid image fusion with a brachytherapy approach (Elekta, Sweden), each on a phantom of 50, 100 and 150 ml prostate volume. The needle trajectories were marked by contrast agent and detected in a postinterventional MRI. Overall target detection rate was 79.6% with a slight superiority for the TPB (83.3 vs. 77.8 vs. 77.8%). TRB with elastic image fusion showed the highest overall precision [median distance to lesion center 2.37 mm (0.14-4.18 mm)], independent of prostate volume. Anterior lesions were significantly more precisely hit than transitional and basal lesions (p = 0.034; p = 0.015) with comparable accuracy for TRB with elastic image fusion and TPB. In general, TRB with rigid image fusion was inferior [median 3.15 mm (0.37-10.62 mm)], particularly in small lesions. All biopsy techniques allow detection of clinically significant tumors with a median error of 2-3 mm. Elastic image fusion appears to be the most precise technique, independent of prostate volume, target size or location.

  2. Cranial Ultrasound/Head Ultrasound

    MedlinePlus

    ... sickle cell disease. It is also used to measure conditions affecting blood flow to and within the brain, such as: Stenosis : ... saved. Doppler ultrasound, a special application of ultrasound, measures ... represent the flow of blood through the blood vessels. top of ...

  3. Mass-spring matching layers for high-frequency ultrasound transducers: a new technique using vacuum deposition.

    PubMed

    Brown, Jeremy; Sharma, Srikanta; Leadbetter, Jeff; Cochran, Sandy; Adamson, Rob

    2014-11-01

    We have developed a technique of applying multiple matching layers to high-frequency (>30 MHz) imaging transducers, by using carefully controlled vacuum deposition alone. This technique uses a thin mass-spring matching layer approach that was previously described in a low-frequency (1 to 10 MHz) transducer design with epoxied layers. This mass- spring approach is more suitable to vacuum deposition in highfrequency transducers over the conventional quarter-wavelength resonant cavity approach, because thinner layers and more versatile material selection can be used, the difficulty in precisely lapping quarter-wavelength matching layers is avoided, the layers are less attenuating, and the layers can be applied to a curved surface. Two different 3-mm-diameter 45-MHz planar lithium niobate transducers and one geometrically curved 3-mm lithium niobate transducer were designed and fabricated using this matching layer approach with copper as the mass layer and parylene as the spring layer. The first planar lithium niobate transducer used a single mass-spring matching network, and the second planar lithium niobate transducer used a single mass-spring network to approximate the first layer in a dual quarter-wavelength matching layer system in addition to a conventional quarter-wavelength layer as the second matching layer. The curved lithium niobate transducer was press focused and used a similar mass-spring plus quarter-wavelength matching layer network. These transducers were then compared with identical transducers with no matching layers and the performance improvement was quantified. The bandwidth of the lithium niobate transducer with the single mass-spring layer was measured to be 46% and the insertion loss was measured to be -21.9 dB. The bandwidth and insertion loss of the lithium niobate transducer with the mass-spring network plus quarter-wavelength matching were measured to be 59% and -18.2 dB, respectively. These values were compared with the unmatched

  4. Intravascular ultrasound guidance of percutaneous coronary intervention in ostial chronic total occlusions: a description of the technique and procedural results.

    PubMed

    Ryan, Nicola; Gonzalo, Nieves; Dingli, Philip; Cruz, Oscar Vedia; Jiménez-Quevedo, Pilar; Nombela-Franco, Luis; Nuñez-Gil, Ivan; Trigo, María Del; Salinas, Pablo; Macaya, Carlos; Fernandez-Ortiz, Antonio; Escaned, Javier

    2017-02-14

    Inability to cross the lesion with a guidewire is the most common reason for failure in percutaneous revascularization (PCI) of chronic total occlusions (CTOs). An ostial or stumpless CTO is an acknowledged challenge for CTO recanalization due to difficulty in successful wiring. IVUS imaging provides the opportunity to visualize the occluded vessel and to aid guidewire advancement. We review the value of this technique in a single-centre experience of CTO PCI. This series involves 22 patients who underwent CTO-PCI using IVUS guidance for stumpless CTO wiring at our institution. CTO operators with extensive IVUS experience in non-CTO cases carried out all procedures. Procedural and outcome data was prospectively entered into the institutional database and a retrospective analysis of clinical, angiographic and technical data performed. 17 (77%) of the 22 procedures were successful. The mean age was 59.8 ± 11.5 years, and 90.9% were male. The most commonly attempted lesions were located in the left anterior descending 36.4% (Soon et al. in J Intervent Cardiol 20(5):359-366, 2007) and Circumflex artery (LCx) 31.8% (Mollet et al. in Am J Cardiol 95(2):240-243, 2005). Mean JCTO score was 3.09 ± 0.75 (3.06 ± 0.68, 3.17 ± 0.98 in the successful and failed groups respectively p = 0.35). The mean contrast volume was 378.7 ml ± 114.7 (389.9 ml ± 130.5, 349.2 ml ± 52.2 p = 0.3 in the successful and failed groups respectively). There was no death, coronary artery bypass grafting or myocardial infarction requiring intervention in this series. When the success rates were analyzed taking into account the date of adoption of this technique, the learning curve had no significant impact on CTO-PCI success. This series describes a good success rate in IVUS guided stumpless wiring of CTOs in consecutive patients with this complex anatomical scenario.

  5. Single, double or multiple-injection techniques for non-ultrasound guided axillary brachial plexus block in adults undergoing surgery of the lower arm.

    PubMed

    Chin, Ki Jinn; Cubillos, Javier E; Alakkad, Husni

    2016-09-02

    Regional anaesthesia comprising axillary block of the brachial plexus is a common anaesthetic technique for distal upper limb surgery. This is an update of a review first published in 2006 and previously updated in 2011 and 2013. To compare the relative effects (benefits and harms) of three injection techniques (single, double and multiple) of axillary block of the brachial plexus for distal upper extremity surgery. We considered these effects primarily in terms of anaesthetic effectiveness; the complication rate (neurological and vascular); and pain and discomfort caused by performance of the block. We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 3), MEDLINE (1946 to April Week 1 2016), Embase (1947 to April 18 2016) and reference lists of trials. We contacted trial authors. The date of the last search was April 2016 (updated from March 2013). We included randomized controlled trials that compared double with single-injection techniques, multiple with single-injection techniques, or multiple with double-injection techniques for axillary block in adults undergoing surgery of the distal upper limb. We excluded trials using ultrasound-guided techniques. Independent study selection, 'Risk of bias' assessment and data extraction were performed by at least two investigators. We undertook meta-analysis. We included one new trial involving 45 participants in this updated review. In total we included 22 trials involving a total of 2193 participants who received regional anaesthesia for hand, wrist, forearm or elbow surgery. 'Risk of bias' assessment indicated that trial design and conduct were generally adequate; the most common areas of weakness were in blinding and allocation concealment.Nine trials comparing double versus single injections showed a statistically significant decrease in primary anaesthesia failure (risk ratio (RR) 0.55, 95% confidence interval (CI) 0.34 to 0.89, high-quality evidence). Subgroup analysis by method of

  6. Historical considerations in the development of modern IUD's: patient and device selection and the importance of insertion techniques.

    PubMed

    Mishell, D R

    1978-03-01

    The Cooperative Statistical Program was initiated in 1963, the 1st effort to evaluate a method of contraception by using pooled data from several clinics and a systematic statistical method. Progress reports were issued from 1963 through 1970. The reports provided epidemiological evidence that Lippes Loop D has the best overall performance of all the IUDs studied. Expulsion, pregnancy, and removal rates for bleeding and pain were measured. Performance rates for all these indices are better with the duration of the device. Since 1970, numbers of new IUDs have been designed and tested clinically. The aim was to improve efficacy, to make IUDs suitable for women who had never been pregnant, and to reduce the incidence of pain and bleeding. The T-shaped IUD has been found to cause lowered rates of removal for pain and bleeding. To counteract the higher pregnancy rate with this device, an antifertility agent can be added to the IUD for timed release. Steroids and copper have both been used. Clinics differ in their performance rates due to differing patient populations, differing physician experience, and differing clinic attitudes. The insertion technique is important to long-term performance.

  7. Clinical ophthalmic ultrasound improvements

    NASA Technical Reports Server (NTRS)

    Garrison, J. B.; Piro, P. A.

    1981-01-01

    The use of digital synthetic aperture techniques to obtain high resolution ultrasound images of eye and orbit was proposed. The parameters of the switched array configuration to reduce data collection time to a few milliseconds to avoid eye motion problems in the eye itself were established. An assessment of the effects of eye motion on the performance of the system was obtained. The principles of synthetic techniques are discussed. Likely applications are considered.

  8. Current standards in abdominal cavity ultrasound examination in children.

    PubMed

    Brzewski, Michał

    2017-03-01

    Technological progress forces us to present after several years the updated standards in ultrasound examination of newborns, infants and older children. It should be emphasized that the examination of the youngest patients requires one to use high-class equipment. Lack of cooperation on the part of the child and imaging small structures constitute a huge challenge for the examiner. The work presents equipment requirements, the technology of examining the abdominal cavity in children and the manner of preparing the examination result. Moreover, modern expectations as regards ultrasound surgery equipment, where children are subject to examination have been presented. The minimum set of transducers the ultrasound apparatus should be equipped with has also been pointed out as well as the minimum requirements concerning image recording. Extending the scope of transducers over "minimum" significantly raises the imaging possibilities in pediatrics. Standard preparation of children for ultrasound has been discussed, taking into consideration the age of the patient and indications. It is essential to understand that it differs from standard preparation for examination in the case of adults. The technique of examining the abdominal cavity has been described, which enables the repeatability of examinations and ensuring making all the available structures visible. It proves imperative especially in the case of a large number of examinations. Attention should be paid particularly to the urinary system imaging - owing to the greatest incidence of congenital diseases in that system.

  9. Ultrasound physics.

    PubMed

    Shriki, Jesse

    2014-01-01

    Bedside ultrasound has become an important modality for obtaining critical information in the acute care of patients. It is important to understand the physics of ultrasound in order to perform and interpret images at the bedside. The physics of both continuous wave and pulsed wave sound underlies diagnostic ultrasound. The instrumentation, including transducers and image processing, is important in the acquisition of appropriate sonographic images. Understanding how these concepts interplay with each other enables practitioners to obtain the best possible images. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Ultrasound in analytical chemistry.

    PubMed

    Priego Capote, F; Luque de Castro, M D

    2007-01-01

    Ultrasound is a type of energy which can help analytical chemists in almost all their laboratory tasks, from cleaning to detection. A generic view of the different steps which can be assisted by ultrasound is given here. These steps include preliminary operations usually not considered in most analytical methods (e.g. cleaning, degassing, and atomization), sample preparation being the main area of application. In sample preparation ultrasound is used to assist solid-sample treatment (e.g. digestion, leaching, slurry formation) and liquid-sample preparation (e.g. liquid-liquid extraction, emulsification, homogenization) or to promote heterogeneous sample treatment (e.g. filtration, aggregation, dissolution of solids, crystallization, precipitation, defoaming, degassing). Detection techniques based on use of ultrasonic radiation, the principles on which they are based, responses, and the quantities measured are also discussed.

  11. WE-EF-210-05: Diagnosis and Quantification of Liver Steatosis with Quantitative Ultrasound Backscatter Technique

    SciTech Connect

    Andre, M; Heba, E; Lin, S; Wolfson, T; Ang, B; Gamst, A; Sirlin, C; Loomba, R; Han, A; Erdman, J; O’Brien, W

    2015-06-15

    Purpose: Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in the United States, affects 30% of adult Americans and may progress to more serious diseases. Liver biopsy is the standard method for diagnosing NAFLD. MRI can accurately diagnose and quantify hepatic steatosis but is expensive. Sonography with qualitative interpretation by radiologists is lower cost, more accessible but less sensitive for detection. The objective of this study, using MRI proton density fat fraction (PDFF) as reference, is to assess the accuracy for diagnosing and quantifying steatosis with two quantitative US parameters-- backscatter coefficient (BSC) and attenuation coefficient (AC)--derived from RF signals using the calibration phantom technique. Methods: We performed a prospective, cross-sectional analysis of a cohort of adults (n=204) with NAFLD (MRI-PDFF≥5%) and without NAFLD (controls). Subjects underwent MRI-PDFF and BSC and AC US analyses of the liver on the same day. Patients were randomly assigned to training (n=102, mean age 51±17 years, mean body mass index 31±7 kg/m{sup 2}) and validation (n=102, mean age 49±17 years, body mass index 30±6 kg/m{sup 2}) groups; 69% of patients in each group had NAFLD. Results: BSC provided AUC 0.98 (95% CI 0.95–1.00, p<0.0001) for diagnosis of NAFLD; the optimal BSC cut-off provided sensitivity, specificity, positive and negative predictive values (PPV, NPV) of 87%, 91%, 95%, and 76%, respectively. AC provided AUC 0.89 (95% CI 0.81–0.96, p<0.0001) for diagnosis of steatosis; the optimal AC cut-off provided sensitivity, specificity, PPV, NPV of 80%, 84%, 92%, and 66%, respectively. BSC and AC both correlated significantly with MRI-PDFF (P<0.0001). Conclusion: QUS BSC and AC can accurately diagnose and quantify hepatic steatosis, using MRI-PDFF as reference. With further validation, QUS may emerge as an inexpensive, widely available tool for NAFLD assessment. General support: NIH R01 CA111289, K

  12. 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

  13. Lessons in modern digital field geology: Open source software, 3D techniques, and the new world of digital mapping

    NASA Astrophysics Data System (ADS)

    Pavlis, Terry; Hurtado, Jose; Langford, Richard; Serpa, Laura

    2014-05-01

    Although many geologists refuse to admit it, it is time to put paper-based geologic mapping into the historical archives and move to the full potential of digital mapping techniques. For our group, flat map digital geologic mapping is now a routine operation in both research and instruction. Several software options are available, and basic proficiency with the software can be learned in a few hours of instruction and practice. The first practical field GIS software, ArcPad, remains a viable, stable option on Windows-based systems. However, the vendor seems to be moving away from ArcPad in favor of mobile software solutions that are difficult to implement without GIS specialists. Thus, we have pursued a second software option based on the open source program QGIS. Our QGIS system uses the same shapefile-centric data structure as our ArcPad system, including similar pop-up data entry forms and generic graphics for easy data management in the field. The advantage of QGIS is that the same software runs on virtually all common platforms except iOS, although the Android version remains unstable as of this writing. A third software option we are experimenting with for flat map-based field work is Fieldmove, a derivative of the 3D-capable program Move developed by Midland Valley. Our initial experiments with Fieldmove are positive, particularly with the new, inexpensive (<300Euros) Windows tablets. However, the lack of flexibility in data structure makes for cumbersome workflows when trying to interface our existing shapefile-centric data structures to Move. Nonetheless, in spring 2014 we will experiment with full-3D immersion in the field using the full Move software package in combination with ground based LiDAR and photogrammetry. One new workflow suggested by our initial experiments is that field geologists should consider using photogrammetry software to capture 3D visualizations of key outcrops. This process is now straightforward in several software packages, and

  14. [Ultrasound-guided peripheral catheterization].

    PubMed

    Salleras-Duran, Laia; Fuentes-Pumarola, Concepció

    2016-01-01

    Peripheral catheterization is a technique that can be difficult in some patients. Some studies have recently described the use of ultrasound to guide the venous catheterization. To describe the success rate, time required, complications of ultrasound-guided peripheral venous catheterization. and patients and professionals satisfaction The search was performed in databases (Medline-PubMed, Cochrane Library, CINAHL and Cuiden Plus) for studies published about ultrasound-guided peripheral venous catheterization performed on patients that provided results on the success of the technique, complications, time used, patient satisfaction and the type of professional who performed the technique. A total of 21 studies were included. Most of them get a higher success rate 80% in the catheterization ecoguide and time it is not higher than the traditional technique. The Technical complications analyzed were arterial puncture rates and lower nerve 10%. In all studies measuring and comparing patient satisfaction in the art ecoguide is greater. Various professional groups perform the technique. The use of ultrasound for peripheral pipes has a high success rate, complications are rare and the time used is similar to that of the traditional technique. The technique of inserting catheters through ultrasound may be learned by any professional group performing venipuncture. Finally, it gets underscores the high patient satisfaction with the use of this technique. Copyright © 2015 Elsevier España, S.L.U. All rights reserved.

  15. Diagnostic accuracies of endoscopic ultrasound-guided fine-needle aspiration with distinct negative pressure suction techniques in solid lesions: A retrospective study

    PubMed Central

    Wang, Ronghua; Wang, Jinlin; Li, Yawen; Duan, Yaqi; Wu, Xiaoli; Cheng, Bin

    2017-01-01

    Endoscopic ultrasound (EUS)-guided fine-needle aspiration (EUS-FNA) is highly accurate in obtaining specific diagnoses for various diseases. The present study aimed to evaluate the diagnostic yields, accuracies and sampling adequacies, of slow-pull, 5 ml suction and 10 ml suction techniques in EUS-FNA of solid lesions. The present study was a retrospective comparative study, which was performed in tertiary academic centers, recognized for their expertise in EUS and EUS-guided FNA. The present study involved 149 patients who underwent EUS-FNA of solid masses. A total of 34 (22.8%), 37 (24.8%) and 78 (52.4%) patients underwent EUS-FNA with slow-pull, 5 ml suction and 10 ml suction techniques, respectively. The EUS-FNA cytology and histology results were compared with those from the gold standard of surgical histopathology [hematoxylin-eosin staining; immunohistochemical test of cluster of differentiation (CD) 79a, CD20 and flow cytometry test] or long-term clinical follow-up. The present retrospective comparative study demonstrated that the diagnostic yields and accuracies of EUS-FNA with slow-pull (86.1%) were significantly superior to those achieved with 5 ml suction (83.3%) or 10 ml suction (69.9%; P<0.0001; χ2 test). Consistently, 86.5% (32/37) of the samples obtained from the 5 ml suction group were adequate for histological diagnosis. By contrast, 70.6 (24/34) and 85.9% (67/78) of samples from the slow-pull and 10 ml suction groups were adequate for histological diagnosis, respectively. The samples obtained using 10 ml suction contained more blood compared with those obtained via slow-pull and 5 ml suction (P=0.0056; χ2 test). No complications were noted in any of the three groups. The samples that were obtained for histopathological diagnosis using 5 ml suction were superior to those obtained using slow-pull or 10 ml suction. Additional multi-central prospective studies in which EUS-FNA is performed with variable negative pressures are required to improve

  16. Endoscopic ultrasound

    MedlinePlus

    ... Pancreatitis References Lee LS. Endoscopic ultrasound. In: McNalley PR, ed. GI/Liver Secrets Plus . 5th ed. Philadelphia, ... member of Hi-Ethics and subscribes to the principles of the Health on the Net Foundation (www. ...

  17. Inspecting what you expect: Applying modern tools and techniques to evaluate the effectiveness of household energy interventions

    NASA Astrophysics Data System (ADS)

    Pillarisetti, Ajay

    Exposure to fine particles (PM2.5) resulting from solid fuel use for household energy needs - including cooking, heating, and lighting - is one of the leading causes of ill-health globally and is responsible for approximately 4 million premature deaths and 84 million lost disability-adjusted life years globally. The well-established links between cooking and ill-health are modulated by complex social, behavioral, technological, and environmental issues that pose unique challenges to efforts that seek to reduce this large health burden. Despite growing interest in the field - and numerous technical solutions that, in the laboratory at least, reduce emissions of harmful air pollutants from solid fuel combustion - there exists a need for refined tools, models, and techniques (1) for measuring environmental pollution in households using solid fuel, (2) for tracking adoption of interventions, and (3) for estimating the potential health benefits attributable to an intervention. Part of the need for higher spatial and temporal resolution data on particular concentrations and dynamics is being met by low-cost sensing platforms that provide large amounts of time-resolved data on critical parameters of interest, including PM2.5 concentrations and time-of-use metrics for heat-generating appliances, like stoves. Use of these sensors can result in non-trivial challenges, including those related to data management and analysis, and field logistics, but also enables novel lines of inquiry and insight. Chapter 2 presents a long-term deployment of real-time PM2.5 sensors in rural, solid-fuel-using kitchens, specifically seeking to evaluate how well commonly measured 24 or 48-hour samples represent long-term means. While short-term measures were poor predictors of long-term means, the dataset enabled evaluation of numerous sampling strategies - including sampling once per week, month, or season - that had much lower errors and higher probabilities of estimating the true mean

  18. The use of ultrasound in obstetric anesthesia.

    PubMed

    Weiniger, Carolyn F; Sharoni, Limor

    2017-06-01

    The current review considers an array of recent applications for point-of-care ultrasound in clinical practice including diagnostic and therapeutic procedures that may be relevant for the obstetric anesthesiologist. The rapid advancement of technology and clinical applications for bedside ultrasound in obstetric anesthesiology requires an appraisal of the limitations and uses. The review presents the most recent literature describing ultrasound-guided airway assessments, airway management, cricothyroidotomy, transthoracic echocardiography, gastric volume assessments, point-of-care lung ultrasound diagnoses, intracranial pressure assessments, vascular access, neuraxial blocks, and transversus abdominis plane blocks. Each ultrasound technique is presented along with the most recent advances in knowledge and some limitations to integration of these ultrasound skills in clinical practice. Anesthesiologists have clearly embraced this facile versatile tool for bedside diagnostics and procedures. One limitation to widespread adoption is availability of suitable ultrasound skills and technology. Many of these ultrasound techniques have not yet established clear patient benefit, yet the sheer breadth of ultrasound techniques reported in the past few years demonstrate that our colleagues are becoming more proficient. It is important to follow the development of this emerging field to be aware of limitations to learning these skills and their potential clinical benefit. Proficiency in some of these point-of-care ultrasound techniques may become prerequisite for obstetric anesthesiologists to provide the best care.

  19. [A variant of the classic technique of ultrasound guided percutaneous renal biopsy: the perpendicular entry by longitudinal viewing planes with a perforated probe].

    PubMed

    Brardi, Simone; Cevenini, Gabriele; Bonadio, Angelo Giovanni; Ponchietti, Roberto; Caremani, Marcello; Duranti, Ennio

    2017-04-01

    The percutaneous biopsy of native kidneys according to the classic methodology, takes place with the introduction of the needle and its guide with ultrasound sagittal viewing planes, with a 30-degree angle, up to the lower pole of the kidney. Since the longitudinal axis of the kidneys converges towards the spine with a sharp angle, we observed that starting from a longitudinal scan of the kidney (conducted along the posterior axillary line with the patient prone) you can drive the needle by a perforated probe through a shorter path perpendicular to the end section of the lower pole of the kidney where the front and rear rims of the cortex bearings without the renal sinus interposed so increasing the chance to obtain, even with a single pass, a good sample of cortical tissue while limiting the possibility to damage the lower chalices that may cause hematuria. We biopsied in that manner 26 patients and we compared the data with those reported in the literature performed with the same needle gauge and post-biopsy monitoring period. With a statistically lower number of needle passes, it is thus obtained the 100% of the sample validity for histological analysis, in absence of major complications and statistically hemoglobin variance when compared with a group of 44 patients biopsied with a significantly greater number of needle passes in the only work carried out with classical technique in the literature (Ori et al.) which is directly comparable to our for gauge of the needles and duration of monitoring. Copyright by Società Italiana di Nefrologia SIN, Rome, Italy.

  20. Trauma Ultrasound.

    PubMed

    Wongwaisayawan, Sirote; Suwannanon, Ruedeekorn; Prachanukool, Thidathit; Sricharoen, Pungkava; Saksobhavivat, Nitima; Kaewlai, Rathachai

    2015-10-01

    Ultrasound plays a pivotal role in the evaluation of acute trauma patients through the use of multi-site scanning encompassing abdominal, cardiothoracic, vascular and skeletal scans. In a high-speed polytrauma setting, because exsanguinations are the primary cause of trauma morbidity and mortality, ultrasound is used for quick and accurate detection of hemorrhages in the pericardial, pleural, and peritoneal cavities during the primary Advanced Trauma Life Support (ATLS) survey. Volume status can be assessed non-invasively with ultrasound of the inferior vena cava (IVC), which is a useful tool in the initial phase and follow-up evaluations. Pneumothorax can also be quickly detected with ultrasound. During the secondary survey and in patients sustaining low-speed or localized trauma, ultrasound can be used to help detect abdominal organ injuries. This is particularly helpful in patients in whom hemoperitoneum is not identified on an initial scan because findings of organ injuries will expedite the next test, often computed tomography (CT). Moreover, ultrasound can assist in detection of fractures easily obscured on radiography, such as rib and sternal fractures.

  1. Bio-refinery of orange peels waste: a new concept based on integrated green and solvent free extraction processes using ultrasound and microwave techniques to obtain essential oil, polyphenols and pectin.

    PubMed

    Boukroufa, Meryem; Boutekedjiret, Chahrazed; Petigny, Loïc; Rakotomanomana, Njara; Chemat, Farid

    2015-05-01

    In this study, extraction of essential oil, polyphenols and pectin from orange peel has been optimized using microwave and ultrasound technology without adding any solvent but only "in situ" water which was recycled and used as solvent. The essential oil extraction performed by Microwave Hydrodiffusion and Gravity (MHG) was optimized and compared to steam distillation extraction (SD). No significant changes in yield were noticed: 4.22 ± 0.03% and 4.16 ± 0.05% for MHG and SD, respectively. After extraction of essential oil, residual water of plant obtained after MHG extraction was used as solvent for polyphenols and pectin extraction from MHG residues. Polyphenols extraction was performed by ultrasound-assisted extraction (UAE) and conventional extraction (CE). Response surface methodology (RSM) using central composite designs (CCD) approach was launched to investigate the influence of process variables on the ultrasound-assisted extraction (UAE). The statistical analysis revealed that the optimized conditions of ultrasound power and temperature were 0.956 W/cm(2) and 59.83°C giving a polyphenol yield of 50.02 mgGA/100 g dm. Compared with the conventional extraction (CE), the UAE gave an increase of 30% in TPC yield. Pectin was extracted by conventional and microwave assisted extraction. This technique gives a maximal yield of 24.2% for microwave power of 500 W in only 3 min whereas conventional extraction gives 18.32% in 120 min. Combination of microwave, ultrasound and the recycled "in situ" water of citrus peels allow us to obtain high added values compounds in shorter time and managed to make a closed loop using only natural resources provided by the plant which makes the whole process intensified in term of time and energy saving, cleanliness and reduced waste water.

  2. Contrast-Enhanced Ultrasound (CEUS) for Echographic Detection of Hepato Cellular Carcinoma in Cirrhotic Patients Previously Treated with Multiple Techniques: Comparison of Conventional US, Spiral CT and 3-Dimensional CEUS with Navigator Technique (3DNav CEUS)

    PubMed Central

    Giangregorio, Francesco

    2011-01-01

    A commercially available technique named “NAVIGATOR” (Esaote, Italy) easily enables a 3-D reconstruction of a single 2-D acquisition of Co