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Sample records for venous elastography validation

  1. Hepatic Venous Outflow Stenosis After Auxiliary Left Hemiliver Transplantation Diagnosed by Ultrasonic Shear Wave Elastography Combined With Doppler Ultrasonography

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    Li, Jia-Wu; Lu, Qiang; Luo, Yan

    2017-01-01

    Abstract Hepatic vein stenosis after liver transplantation is a relatively rare complication that could even result in graft loss. However, it is difficult to arrive at a definite diagnosis at the early stage of postoperation, and there are few researches on ultrasonic shear wave elastography in the diagnosis of hepatic vein stenosis. We report the case of an 11-year-old male patient with cirrhosis due to hepatolenticular degeneration who received an auxiliary left hemiliver graft from his uncle. Massive ascites developed in 4 days after the operation. Stenosis was suspected at the site of anastomosis by Doppler ultrasonography when elevating the velocity of the left hepatic vein. Meanwhile, increased stiffness of the graft was revealed by ultrasonic shear wave elastography. The stenosis was confirmed by subsequent digital subtraction angiography. Ascites decreased gradually after the stent implantation. Our case indicates that ultrasonic shear wave elastography combined with Doppler ultrasonography is a promising method for noninvasive diagnosis of hepatic venous outflow stenosis following liver transplantation. PMID:29190228

  2. Ultrasound Elastography for Determination of the Age of Venous Thrombi. Evaluation of Thrombus Evolution in Patients After Sclerotherapy.

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    Paluch, Łukasz; Nawrocka-Laskus, Ewa; Dąbrowska, Agnieszka; Popiela, Tadeusz; Walecki, Jerzy

    2017-01-01

    Venous thrombosis is a multicausal disease involving intravenous clot formation. It may occur spontaneously or after provoking events, such as traumatic injuries to the pelvis, upper and lower extermities, immobilization, intravascular procedures, including venous catheterization or injection. Color Doppler ultrasonography is a rapid and non-invasive technique for evaluation of venous disease. It is a very sensitive method for detection of thrombi, but has some limitations, e.g. inability to distinguish between an old and fresh thrombus. Elastography as a method for evaluation of tissue elasticity and allows more accurate assessment of venous thombosis. The thrombus solidifies significantly during the process of remodeling, thereby changing elasticity, while the tissues located around the vessel remain unchanged. Moreover, the homogeneity of the thrombus is also changed. These factors allow for exact determination of the age of the thrombus depending on changes of its elasticity. The object of this study was to assess thrombus age in patients with saphenous vein insufficiency treated with sclerotherapy. We examined 34 patients, 30 women and 4 men, aged 18-62 years. All short-listed patients with initial 7-8 mm vessel diameter underwent treatment with 3% Aetoxysklerol mixed with CO2 and other respiratory gases. Data acquisition was performed using an Esaote MyLab Twice device with LA523 linear probe. On the sixth day after the treatment 31 patients presented uniform, hypoechogenic thrombus in B-mode image. Ultrasound-based elasticity images (elastography) showed significant predominant red and green areas. Blue area was either invisible or appeared in insignificant grade on examined area. The mosaic image of colors appeared on 2 patients. On the fourteenth day of study 21 patients still presented hypoechogenic thrombus, whereas mixed echogenicity of thrombus appeared on 11 patients. On 28 examined patients mosaics of red, green and blue colors were observed, with

  3. Ultrasound-Based Carotid Elastography for Detection of Vulnerable Atherosclerotic Plaques Validated by Magnetic Resonance Imaging.

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    Huang, Chengwu; Pan, Xiaochang; He, Qiong; Huang, Manwei; Huang, Lingyun; Zhao, Xihai; Yuan, Chun; Bai, Jing; Luo, Jianwen

    2016-02-01

    Ultrasound-based carotid elastography has been developed to estimate the mechanical properties of atherosclerotic plaques. The objective of this study was to evaluate the in vivo capability of carotid elastography in vulnerable plaque detection using high-resolution magnetic resonance imaging as reference. Ultrasound radiofrequency data of 46 carotid plaques from 29 patients (74 ± 5 y old) were acquired and inter-frame axial strain was estimated with an optical flow method. The maximum value of absolute strain rate for each plaque was derived as an indicator for plaque classification. Magnetic resonance imaging of carotid arteries was performed on the same patients to classify the plaques into stable and vulnerable groups for carotid elastography validation. The maximum value of absolute strain rate was found to be significantly higher in vulnerable plaques (2.15 ± 0.79 s(-1), n = 27) than in stable plaques (1.21 ± 0.37 s(-1), n = 19) (p magnetic resonance imaging, was proven, revealing the potential of carotid elastography as an important tool in atherosclerosis assessment and stroke prevention. Copyright © 2016 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  4. Transient elastography versus hepatic venous pressure gradient for diagnosing portal hypertension: a systematic review and meta-analysis

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    Gaeun Kim

    2017-03-01

    Full Text Available Background/Aims Transient elastography (TE has been proposed as a promising noninvasive alternative to hepatic venous pressure gradient (HVPG for detecting portal hypertension (PH. However, previous studies have yielded conflicting results. We gathered evidence from literature on the clinical usefulness of TE versus HVPG for assessing PH. Methods We conducted a systematic review by searching databases for relevant literature evaluating the clinical usefulness of non-invasive TE for assessing PH in patients with cirrhosis. A literature search in Ovid Medline, EMBASE and the Cochrane Library was performed for all studies published prior to December 30, 2015. Results Eight studies (1,356 patients met our inclusion criteria. For the detection of PH (HVPG ≥6 mmHg, the summary sensitivity and specificity were 0.88 (95% confidence interval [CI] 0.86-0.90 and 0.74 (95% CI 0.67-0.81, respectively. Regarding clinically significant PH (HVPG ≥10 mmHg, the summary sensitivity and specificity were 0.85 (95% CI 0.63-0.97 and 0.71 (95% CI 0.50-0.93, respectively. The overall correlation estimate of TE and HVPG was large (0.75, 95% CI: 0.65; 0.82, P<0.0001. Conclusions TE showed high accuracy and correlation for detecting the severity of PH. Therefore, TE shows promise as a reliable and non-invasive procedure for the evaluation of PH that should be integrated into clinical practice.

  5. Arterial waveguide model for shear wave elastography: implementation and in vitro validation

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    Vaziri Astaneh, Ali; Urban, Matthew W.; Aquino, Wilkins; Greenleaf, James F.; Guddati, Murthy N.

    2017-07-01

    Arterial stiffness is found to be an early indicator of many cardiovascular diseases. Among various techniques, shear wave elastography has emerged as a promising tool for estimating local arterial stiffness through the observed dispersion of guided waves. In this paper, we develop efficient models for the computational simulation of guided wave dispersion in arterial walls. The models are capable of considering fluid-loaded tubes, immersed in fluid or embedded in a solid, which are encountered in in vitro/ex vivo, and in vivo experiments. The proposed methods are based on judiciously combining Fourier transformation and finite element discretization, leading to a significant reduction in computational cost while fully capturing complex 3D wave propagation. The developed methods are implemented in open-source code, and verified by comparing them with significantly more expensive, fully 3D finite element models. We also validate the models using the shear wave elastography of tissue-mimicking phantoms. The computational efficiency of the developed methods indicates the possibility of being able to estimate arterial stiffness in real time, which would be beneficial in clinical settings.

  6. Assistance protocol for venous ulcers patients: validation of contents

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    Daniele Vieira Dantas

    2013-07-01

    Full Text Available Venous ulcers require complex treatment and are responsible for significant morbidity and mortality rates. This study aims at identifying aspects validated by the jury for the preparation of an assistance protocol for venous ulcer sufferers. It is a descriptive and quantitative research, with 39 professionals (30 nurses, 7 doctors and two physiotherapists, held at the Onofre Lopes University Hospital, between April and July/2010. Data collection began through a questionnaire checklist. Analysis was performed through Statistical Package for Social Science 15.0, assessing compliance with guidelines. Results were the compositional aspects of the protocol: assessment of patient and lesion history/documentation, wound care/perilesional skin, dressing suggestion, use of antibiotics and pain treatment, surgical treatment/medication, improving venous return and relapse prevention, patient referral, professional training and referral/counter-referral. It was concluded that to compose the protocol, aspects related to diagnosis, treatment and injury prevention must be considered.

  7. Validation and reproducibility assessment of modality independent elastography in a pre-clinical model of breast cancer

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    Weis, Jared A.; Kim, Dong K.; Yankeelov, Thomas E.; Miga, Michael I.

    2014-03-01

    Clinical observations have long suggested that cancer progression is accompanied by extracellular matrix remodeling and concomitant increases in mechanical stiffness. Due to the strong association of mechanics and tumor progression, there has been considerable interest in incorporating methodologies to diagnose cancer through the use of mechanical stiffness imaging biomarkers, resulting in commercially available US and MR elastography products. Extension of this approach towards monitoring longitudinal changes in mechanical properties along a course of cancer therapy may provide means for assessing early response to therapy; therefore a systematic study of the elasticity biomarker in characterizing cancer for therapeutic monitoring is needed. The elastography method we employ, modality independent elastography (MIE), can be described as a model-based inverse image-analysis method that reconstructs elasticity images using two acquired image volumes in a pre/post state of compression. In this work, we present preliminary data towards validation and reproducibility assessment of our elasticity biomarker in a pre-clinical model of breast cancer. The goal of this study is to determine the accuracy and reproducibility of MIE and therefore the magnitude of changes required to determine statistical differences during therapy. Our preliminary results suggest that the MIE method can accurately and robustly assess mechanical properties in a pre-clinical system and provide considerable enthusiasm for the extension of this technique towards monitoring therapy-induced changes to breast cancer tissue architecture.

  8. Development and validation of educational technology for venous ulcer care.

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    Benevides, Jéssica Lima; Coutinho, Janaina Fonseca Victor; Pascoal, Liliane Chagas; Joventino, Emanuella Silva; Martins, Mariana Cavalcante; Gubert, Fabiane do Amaral; Alves, Allana Mirella

    2016-04-01

    To develop and validate an educational technology venous ulcers care. Methodological study conducted in five steps: Situational diagnosis; literature review; development of texts, illustrations and layout; apparent and content validity by the Content Validity Index, assessment of Flesch Readability Index; and pilot testing. The developed technology was a type of booklet entitled Booklet for Venous Ulcers Care, consisting of seven topics: Diet and food intake, walking and light exercise, resting with elevated leg, bandage care, compression therapy, family support, and keeping healthy habits. The apparent validity revealed minimal agreement of 85.7% in the clarity and comprehensibility. The total content validity index was 0.97, the Flesch Readability Index was 75%, corresponding to the reading "fairly easy". The pilot test showed that 100% of people with venous ulcers evaluated the text and the illustrations as understandable, as appropriate. The educational technology proved to be valid for the appearance and content with potential for use in clinical practice. Construir e validar uma tecnologia educativa para cuidados com úlcera venosa. Estudo metodológico realizado em cinco fases: diagnóstico situacional; revisão da literatura; desenvolvimento de textos, ilustrações e diagramação; validade de aparência e de conteúdo pelo Índice de Validade de Conteúdo, avaliação do Índice de Legibilidade de Flesch; e teste piloto. A tecnologia desenvolvida foi do tipo cartilha intitulada Cartilha para cuidados com úlcera venosa, constituída de sete tópicos: Alimentação, Caminhadas e exercícios leves, Repouso com a perna elevada, Cuidados com o curativo, Terapia compressiva, Apoio familiar, e manter hábitos saudáveis. A validade aparente revelou concordância mínima de 85,7% na clareza e compreensibilidade. O Índice de Validade de Conteúdo total foi de 0,97, o Índice de legibilidade de Flesch foi de 75%, o que correspondeu à leitura "razoavelmente f

  9. Validation of Ultrasound Elastography Imaging for Nondestructive Characterization of Stiffer Biomaterials.

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    Zhou, Haoyan; Goss, Monika; Hernandez, Christopher; Mansour, Joseph M; Exner, Agata

    2016-05-01

    Ultrasound elastography (UE) has been widely used as a "digital palpation" tool to characterize tissue mechanical properties in the clinic. UE benefits from the capability of noninvasively generating 2-D elasticity encoded maps. This spatial distribution of elasticity can be especially useful in the in vivo assessment of tissue engineering scaffolds and implantable drug delivery platforms. However, the detection limitations have not been fully characterized and thus its true potential has not been completely discovered. Characterization studies have focused primarily on the range of moduli corresponding to soft tissues, 20-600 kPa. However, polymeric biomaterials used in biomedical applications such as tissue scaffolds, stents, and implantable drug delivery devices can be much stiffer. In order to explore UE's potential to assess mechanical properties of biomaterials in a broader range of applications, this work investigated the detection limit of UE strain imaging beyond soft tissue range. To determine the detection limit, measurements using standard mechanical testing and UE on the same polydimethylsiloxane samples were compared and statistically evaluated. The broadest detection range found based on the current optimized setup is between 47 kPa and 4 MPa which exceeds the modulus of normal soft tissue suggesting the possibility of using this technique for stiffer materials' mechanical characterization. The detectable difference was found to be as low as 157 kPa depending on sample stiffness and experimental setup.

  10. Noninvasive vascular ultrasound elastography applied to the characterization of experimental aneurysms and follow-up after endovascular repair

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    Fromageau, Jeremie; Maurice, Roch Listz; Cloutier, Guy [Laboratory of Biorheology and Medical Ultrasonics, University of Montreal Hospital Research Center (CRCHUM), Montreal, Quebec, H2L 2W5 (Canada); Lerouge, Sophie [Laboratory of Endovascular Biomaterials, University of Montreal Hospital Research Center (CRCHUM), Montreal, Quebec, H2L 2W5 (Canada) and Department of Mechanical Engineering, Ecole de Technologie Superieure, Montreal, Quebec, H3C 1K3 (Canada); Soulez, Gilles [Department of Radiology, University of Montreal Hospital, Montreal, Quebec, H2L 4M1 (Canada)], E-mail: guy.cloutier@umontreal.ca

    2008-11-21

    Experimental and simulation studies were conducted to noninvasively characterize abdominal aneurysms with ultrasound (US) elastography before and after endovascular treatment. Twenty three dogs having bilateral aneurysms surgically created on iliac arteries with venous patches were investigated. In a first set of experiments, the feasibility of elastography to differentiate vascular wall elastic properties between the aneurismal neck (healthy region) and the venous patch (pathological region) was evaluated on six dogs. Lower strain values were found in venous patches (p < 0.001). In a second set of experiments, 17 dogs having endovascular repair (EVAR) by stent graft (SG) insertion were examined three months after SG implantation. Angiography, color Doppler US, examination of macroscopic sections and US elastography were used. The value of elastography was validated with the following end points by considering a solid thrombus of a healed aneurysm as a structure with small deformations and a soft thrombus associated with endoleaks as a more deformable tissue: (1) the correlation between the size of healed organized thrombi estimated by elastography and by macroscopic examinations; (2) the correlation between the strain amplitude measured within vessel wall elastograms and the leak size; and (3) agreement on the presence and size of endoleaks as determined by elastography and by combined reference imaging modalities (angiography + Doppler US). Mean surfaces of solid thrombi estimated with elastography were found correlated with those measured on macroscopic sections (r = 0.88, p < 0.001). Quantitative strain values measured within the vessel wall were poorly linked with the leak size (r = 0.12, p = 0.5). However, the qualitative evaluation of leak size in the aneurismal sac was very good, with a Kappa agreement coefficient of 0.79 between elastography and combined reference imaging modalities. In summary, complementing B-scan and color Doppler, noninvasive US

  11. Female striated urogenital sphincter contraction measured by shear wave elastography during pelvic floor muscle activation: Proof of concept and validation.

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    Aljuraifani, Rafeef; Stafford, Ryan E; Hug, François; Hodges, Paul W

    2017-04-13

    Investigation of the function of the striated urogenital sphincter (SUS) is challenging because it is difficult to access and requires invasive measures. Ultrasound shear wave elastography (SWE) is a non-invasive real-time technique used to estimate tissue stiffness. As muscle stiffness can be used as an estimate of muscle force, SWE provides an opportunity to study contraction of the peri-urethral musculature. Validation of SWE to study SUS during functional tasks, such as pelvic floor muscle contractions, is required prior to application in clinical populations. Ten healthy females (34[5] years) participated. Stiffness in a region expected to contain the SUS was quantified using SWE at rest and during a pelvic floor muscle contractions performed at 10%, 25%, and 50% of maximal voluntary contraction (MVC). Two repetitions were performed for 10 s. During contraction, stiffness increased in the region of the SUS in all participants and at all contraction intensities. Multiple regions of increased stiffness were detected, with 95.8% of regions situated ventral to the mid-urethra within the anatomical area of the SUS. The increase in stiffness was greater for 50% MVC than both 10% and 25% MVC contraction intensities (P < 0.01). Stiffness increased within the anatomical region of the SUS during voluntary pelvic floor muscle contractions with predictable response to changes in contraction intensity. These observations support the potential for ultrasound SWE to study SUS function non-invasively. © 2017 Wiley Periodicals, Inc.

  12. A content validated questionnaire for assessment of self reported venous blood sampling practices

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    Bölenius Karin

    2012-01-01

    Full Text Available Abstract Background Venous blood sampling is a common procedure in health care. It is strictly regulated by national and international guidelines. Deviations from guidelines due to human mistakes can cause patient harm. Validated questionnaires for health care personnel can be used to assess preventable "near misses"--i.e. potential errors and nonconformities during venous blood sampling practices that could transform into adverse events. However, no validated questionnaire that assesses nonconformities in venous blood sampling has previously been presented. The aim was to test a recently developed questionnaire in self reported venous blood sampling practices for validity and reliability. Findings We developed a questionnaire to assess deviations from best practices during venous blood sampling. The questionnaire contained questions about patient identification, test request management, test tube labeling, test tube handling, information search procedures and frequencies of error reporting. For content validity, the questionnaire was confirmed by experts on questionnaires and venous blood sampling. For reliability, test-retest statistics were used on the questionnaire answered twice. The final venous blood sampling questionnaire included 19 questions out of which 9 had in total 34 underlying items. It was found to have content validity. The test-retest analysis demonstrated that the items were generally stable. In total, 82% of the items fulfilled the reliability acceptance criteria. Conclusions The questionnaire could be used for assessment of "near miss" practices that could jeopardize patient safety and gives several benefits instead of assessing rare adverse events only. The higher frequencies of "near miss" practices allows for quantitative analysis of the effect of corrective interventions and to benchmark preanalytical quality not only at the laboratory/hospital level but also at the health care unit/hospital ward.

  13. Prosthetic venous valve patient selection by validated physics-based computational models.

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    Chen, Henry Y; Berwick, Zachary C; Kemp, Arika; Krieger, Joshua; Chambers, Sean; Lurie, Fedor; Kassab, Ghassan S

    2015-01-01

    There is significant interest in a venous prosthesis to replace insufficient valves. The aim of the current study was to select the patients with hemodynamic conditions most likely to benefit from a valve implant. The hypothesis is that the venous valve prosthesis is most suitable for patients with significant reflux, such as in chronic venous insufficiency (CVI), right heart hypertrophy (RHH), and right heart failure (RHF). Conversely, a prosthetic valve is likely to be of least benefit for deep venous thrombosis (DVT) patients with low flow. To address this hypothesis, fully coupled fluid and solid mechanics computational models were developed and validated in five acute canine implants. The animal-validated simulations were then carried out for the CVI, RHH, RHF, and DVT patients based on literature hemodynamic data. A mechanical stress ratio of leaflet wall stress to fluid wall shear stress was defined to combine the effects of both fluid mechanics and solid mechanics on leaflet function, for which a lower stress ratio is hemodynamically desirable. The simulation results of mean valve flow velocity and percentage valve opening were found to be within 10% of the measurements in canines. The simulations show that the patients in the CVI classes 4 to 6, RHH patients, and RHF patients may have a significant reduction in stress ratio with virtual implant of a prosthetic valve. The DVT patient simulations demonstrate a minimal reduction in the stress ratio. After thrombus removal where flow is restored, however, the prosthetic valve may be helpful for post-thrombotic patients. For patient selections of the venous valve prosthesis, the most suitable patients are the CVI classes 4 to 6, RHH, and RHF patients. The least suitable patients are the DVT patients because a valve is not effective under low-flow conditions. The present study demonstrates a physics-based approach to patient selection that can be tested in future clinical trials. Copyright © 2015 Society for

  14. A computational model-based validation of Guyton's analysis of cardiac output and venous return curves

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    Mukkamala, R.; Cohen, R. J.; Mark, R. G.

    2002-01-01

    Guyton developed a popular approach for understanding the factors responsible for cardiac output (CO) regulation in which 1) the heart-lung unit and systemic circulation are independently characterized via CO and venous return (VR) curves, and 2) average CO and right atrial pressure (RAP) of the intact circulation are predicted by graphically intersecting the curves. However, this approach is virtually impossible to verify experimentally. We theoretically evaluated the approach with respect to a nonlinear, computational model of the pulsatile heart and circulation. We developed two sets of open circulation models to generate CO and VR curves, differing by the manner in which average RAP was varied. One set applied constant RAPs, while the other set applied pulsatile RAPs. Accurate prediction of intact, average CO and RAP was achieved only by intersecting the CO and VR curves generated with pulsatile RAPs because of the pulsatility and nonlinearity (e.g., systemic venous collapse) of the intact model. The CO and VR curves generated with pulsatile RAPs were also practically independent. This theoretical study therefore supports the validity of Guyton's graphical analysis.

  15. Magnetic resonance elastography: Inversions in bounded media.

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    Kolipaka, Arunark; McGee, Kiaran P; Manduca, Armando; Romano, Anthony J; Glaser, Kevin J; Araoz, Philip A; Ehman, Richard L

    2009-12-01

    Magnetic resonance elastography is a noninvasive imaging technique capable of quantifying and spatially resolving the shear stiffness of soft tissues by visualization of synchronized mechanical wave displacement fields. However, magnetic resonance elastography inversions generally assume that the measured tissue motion consists primarily of shear waves propagating in a uniform, infinite medium. This assumption is not valid in organs such as the heart, eye, bladder, skin, fascia, bone and spinal cord, in which the shear wavelength approaches the geometric dimensions of the object. The aim of this study was to develop and test mathematical inversion algorithms capable of resolving shear stiffness from displacement maps of flexural waves propagating in bounded media such as beams, plates, and spherical shells, using geometry-specific equations of motion. Magnetic resonance elastography and finite element modeling of beam, plate, and spherical shell phantoms of various geometries were performed. Mechanical testing of the phantoms agreed with the stiffness values obtained from finite element modeling and magnetic resonance elastography data, and a linear correlation of r(2) >or= 0.99 was observed between the stiffness values obtained using magnetic resonance elastography and finite element modeling data. In conclusion, we have demonstrated new inversion methods for calculating shear stiffness that may be more appropriate for waves propagating in bounded media. (c) 2009 Wiley-Liss, Inc.

  16. Mechanics of ultrasound elastography.

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    Li, Guo-Yang; Cao, Yanping

    2017-03-01

    Ultrasound elastography enables in vivo measurement of the mechanical properties of living soft tissues in a non-destructive and non-invasive manner and has attracted considerable interest for clinical use in recent years. Continuum mechanics plays an essential role in understanding and improving ultrasound-based elastography methods and is the main focus of this review. In particular, the mechanics theories involved in both static and dynamic elastography methods are surveyed. They may help understand the challenges in and opportunities for the practical applications of various ultrasound elastography methods to characterize the linear elastic, viscoelastic, anisotropic elastic and hyperelastic properties of both bulk and thin-walled soft materials, especially the in vivo characterization of biological soft tissues.

  17. Mechanics of ultrasound elastography

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    Li, Guo-Yang

    2017-01-01

    Ultrasound elastography enables in vivo measurement of the mechanical properties of living soft tissues in a non-destructive and non-invasive manner and has attracted considerable interest for clinical use in recent years. Continuum mechanics plays an essential role in understanding and improving ultrasound-based elastography methods and is the main focus of this review. In particular, the mechanics theories involved in both static and dynamic elastography methods are surveyed. They may help understand the challenges in and opportunities for the practical applications of various ultrasound elastography methods to characterize the linear elastic, viscoelastic, anisotropic elastic and hyperelastic properties of both bulk and thin-walled soft materials, especially the in vivo characterization of biological soft tissues. PMID:28413350

  18. Improving the validity of peripheral venous blood gas analysis as an estimate of arterial blood gas by correcting the venous values with SvO₂.

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    Lemoël, Fabien; Govciyan, Sandra; El Omri, Mouna; Marquette, Charles-Hugo; Levraut, Jacques

    2013-03-01

    Peripheral venous blood gas (pVBG) analysis in replacement of arterial blood gas (ABG) is limited by the unpredictable differences between arterial and venous values, especially for PCO2 and pH (ΔPCO2 and ΔpH). We hypothesized that, using the theoretical relationship linking SvO2 and blood flow, we could diminish the effect of local circulatory conditions on ΔPCO2 and ΔpH and thereby increase pVBG validity. This was a prospective cross-sectional study performed in emergency patients requiring a blood gas analysis in which ABG and pVBG were performed simultaneously. The data of 50 randomly selected patients (model group) were used for developing two equations to correct PvCO2 and pHv according to the peripheral SvO2 (SpvO2) level. The formulas derived were PvCO2cor = PvCO2 - 0.30 × (75 - SpvO2), and pHvcor = pHv + 0.001 × (75 - SpvO2). The validity of the corrected values was then tested on the remaining population (validation group). There were 281 patients included in the study, mainly for dyspnea. ΔPCO2 and ΔpH were strongly correlated with SpvO2 (r(2) = 0.62 and r(2) = 0.53, respectively, p 45 mm Hg (AUC ROC = 0.96 ± 0.01 vs. 0.89 ± 0.02, p 7.45 (AUC = 0.91 ± 0.02 vs. 0.81 ± 0.04, p < 0.001). The variability of ΔPCO2 and ΔpH is significantly lowered when the venous values are corrected according to the SpvO2 value, and pVBG is therefore more accurate and valid for detecting an arterial abnormality. Copyright © 2013 Elsevier Inc. All rights reserved.

  19. Validation of the VEINES-QOL quality of life instrument in venous leg ulcers: repeatability and validity study embedded in a randomised clinical trial.

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    Bland, J Martin; Dumville, Jo C; Ashby, Rebecca L; Gabe, Rhian; Stubbs, Nikki; Adderley, Una; Kang'ombe, Arthur R; Cullum, Nicky A

    2015-08-11

    VEINES-QOL/Sym is a disease-specific quality of life instrument for use in venous diseases of the leg. Its relative scoring system precludes comparisons between studies. There were very few venous leg ulcer patients in the validation samples. We report a validation study for venous leg ulcers and develop a scoring system which enables comparison between studies. Four hundred fifty-one participants in the VenUS IV trial of the management of venous leg ulcers were asked to complete a VEINES-QOL questionnaire at recruitment, along with SF-12, pain, and other aspects of quality of life. VEINES-QOL was repeated after two weeks and after 4 months. Healing of ulcers was confirmed by blind assessment of digital photographs. Three scoring systems for VEINES-QOL were compared. No floor or ceiling effects were observed for VEINES-QOL items, item-item correlations were weak to moderate, item-score correlations were moderate. Internal reliability was good. The VEINES-Sym subscale was confirmed by factor analysis. Test-retest reliability was satisfactory for the scale scores; individual items showed moderate to good agreement. Relationships with SF-12, pain, and the quality items confirmed construct validity. Participants whose ulcers had healed showed greater mean increase in scores than did those yet to heal, though they continued to report leg problems. An intrinsic scoring method appeared superior to the original relative method. VEINES-QOL was suitable for use in the study of venous leg ulcers. The intrinsic scoring method should be adopted, to facilitate comparisons between studies. VenUS IV is registered with the ISRCTN register, number ISRCTN49373072 .

  20. Sonographic Elastography of Mastitis.

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    Sousaris, Nicholas; Barr, Richard G

    2016-08-01

    Sonographic elastography has been shown to be a useful imaging modality in characterizing breast lesions as benign or malignant. However, in preliminary research, mastitis has given false-positive findings on both strain and shear wave elastography. In this article, we review the findings in mastitis with and without abscess formation on both strain and shear wave elastography. The elastographic findings in all cases were suggestive of a malignancy according to published thresholds. In cases of mastitis with abscess formation, there is a characteristic appearance, with a central very soft area (abscess cavity) and a very stiff outer rim (edema and inflammation). This appearance should raise the suspicion of mastitis with abscess formation, since these findings are rare in breast cancers.

  1. Hemoglobin measured by Hemocue and a reference method in venous and capillary blood: a validation study

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    Neufeld Lynnette

    2002-01-01

    Full Text Available Objective. To assess the comparability of hemoglobin concentration (Hb in venous and capillary blood measured by Hemocue and an automated spectrophotometer (Celldyn and to document the influence of type of blood (capillary or venous and analysis method on anemia prevalence estimates. Material and Methods. Between February and May 2000, capillary and venous samples were collected from 72 adults and children at Hospital del Niño Morelense (Morelos State Children's Hospital in Cuernavaca, Morelos, Mexico, and assessed for Hb using the Hemocue and Celldyn methods. Estimated Hb levels were compared using the concordance correlation coefficient and Student's t test for paired data. The sensitivity and specificity for anemia diagnosis were estimated and compared between type of blood and method of assessment. Results. Capillary blood had higher Hb (+0.5g/dl than venous blood in adults and children, as did samples assessed by Celldyn compared to Hemocue (+0.3g/dl. Specificity to detect anemia was adequate (>0.90 but sensitivity was low for capillary blood assessed by Hemocue (<0.80. Conclusions. The difference in Hb between venous and capillary blood is likely related to biological variability. Hemoglobin concentration in capillary blood assessed by Hemocue provides an adequate estimation of population anemia prevalence but may result in excess false negative diagnoses among individuals. The results of this study stress the importance of sample collection technique, particularly for children. Method of analysis and sampling site need to be taken into consideration in field studies.

  2. Hemoglobin measured by Hemocue and a reference method in venous and capillary blood: a validation study.

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    Neufeld, Lynnette; García-Guerra, Armando; Sánchez-Francia, Domingo; Newton-Sánchez, Oscar; Ramírez-Villalobos, María Dolores; Rivera-Dommarco, Juan

    2002-01-01

    To assess the comparability of hemoglobin concentration (Hb) in venous and capillary blood measured by Hemocue and an automated spectrophotometer (Celldyn) and to document the influence of type of blood (capillary or venous) and analysis method on anemia prevalence estimates. Between February and May 2000, capillary and venous samples were collected from 72 adults and children at Hospital del Niño Morelense (Morelos State Children's Hospital) in Cuernavaca, Morelos, Mexico, and assessed for Hb using the Hemocue and Celldyn methods. Estimated Hb levels were compared using the concordance correlation coefficient and Student's t test for paired data. The sensitivity and specificity for anemia diagnosis were estimated and compared between type of blood and method of assessment. Capillary blood had higher Hb (+0.5 g/dl) than venous blood in adults and children, as did samples assessed by Celldyn compared to Hemocue (+0.3 g/dl). Specificity to detect anemia was adequate (> 0.90) but sensitivity was low for capillary blood assessed by Hemocue (< 0.80). The difference in Hb between venous and capillary blood is likely related to biological variability. Hemoglobin concentration in capillary blood assessed by Hemocue provides an adequate estimation of population anemia prevalence but may result in excess false negative diagnoses among individuals. The results of this study stress the importance of sample collection technique, particularly for children. Method of analysis and sampling site need to be taken into consideration in field studies. The English version of this paper is available too at: http://www.insp.mx/salud/index.html.

  3. Elastography of the thyroid.

    Science.gov (United States)

    Monpeyssen, H; Tramalloni, J; Poirée, S; Hélénon, O; Correas, J-M

    2013-05-01

    Thyroid nodules are very common, while thyroid cancer is rare and has a very good prognosis. Thyroid nodule ultrasound characterization performed by experienced clinicians allows the selection of the tumours to be punctured and guiding fine needle aspiration (FNA). FNA provide cytology information able to differentiate benign tumours from cancer in approximately 80% of cases. However, it remains difficult to identify thyroid cancers with ultrasound imaging, as demonstrated by the very low rate of cancers detected in all of the carried out FNA (approximately 5%). As a majority of thyroid cancers are hard, the stiffness evaluation has become part of nodular characterization. Since 2005, elastography has been used for the evaluation of thyroid nodules; quasi-static elastography was the first technique available and used, at first, an external pressure induced by the probe, which was then replaced by carotid internal excitation allowing improvement in sensitivity. Semi-quantitative analysis allows comparison of tissue elasticities between tissue with elasticity anomalies and normal tissue and provides therefore useful analytic information. Shear wave elastography (SWE) provides a map of the elasticity in a region and allows stiffness quantification of lesions in kilopascals in order to reinforce the predictive value of malignancy. A tumour whose stiffness is greater than 65kPa or for which the stiffness ratio is greater than 3.7 compared to surrounding healthy tissue is highly suspicious. SWE may enable the detection of malignant follicular tumours that currently escape detection by the ultrasound-guided ultrasound/aspiration cytology couple. Lymph node metastasis of papillary thyroid cancer can also be detected by elastography due to its increased stiffness. Copyright © 2013. Published by Elsevier Masson SAS.

  4. Psychometric Validation of the 14 items ChronIc Venous Insufficiency Quality of Life Questionnaire (CIVIQ-14): Confirmatory Factor Analysis.

    Science.gov (United States)

    Le Moine, J-G; Fiestas-Navarrete, L; Katumba, K; Launois, R

    2016-02-01

    The study aim was to confirm the factorial structure of the short (14 item) version of the ChronIc Venous Insufficiency quality of life Questionnaire (CIVIQ-14) using the Vein Consult Program (VCP) results. The international VCP study sought to evaluate the impact of chronic venous disease (CVD) on health care costs and quality of life (QoL). The factorial structure of the CIVIQ-14 was evaluated using two methods: exploratory factor analysis (EFA) to calculate the probabilities of items and dimensions remaining stable and to study the dimensionality of the scale using explained variance criteria, followed by confirmatory factor analysis (CFA) to confirm the original three dimensional structure and investigate alternative models that may have arisen from the dimensionality analysis. We also used the VCP results to evaluate the psychometric properties of the questionnaire and conducted subgroup analyses on countries with validated translations. A total of 47,149 questionnaires from 17 countries were available in the VCP. EFA revealed both items and dimensions as 100% stable. Dimensionality analysis showed that a two factor approach could be considered. CFA revealed the CIVIQ-14 three dimensional structure to be acceptable while rejecting the two dimensional model. Psychometric analysis confirmed the construct validity, internal consistency, and known groups validity of the CIVIQ-14. The results of subgroup analyses were consistent with those of the primary analysis. CFA of VCP data supported the factorial structure of the CIVIQ-14. The analysis corroborates the wide use of CIVIQ-14 as a valid instrument for reporting QoL in CVD patients. Copyright © 2015 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

  5. The Anti-Clot Treatment Scale (ACTS in clinical trials: cross-cultural validation in venous thromboembolism patients

    Directory of Open Access Journals (Sweden)

    Cano Stefan J

    2012-09-01

    Full Text Available Abstract Background The Anti-Clot Treatment Scale (ACTS is a 15-item patient-reported instrument of satisfaction with anticoagulant treatment. It includes a 12-item ACTS Burdens scale and a 3-item ACTS Benefits scale. Its role in clinical trials and other settings should be supported by evidence that it is both clinically meaningful and scientifically sound. The aim of the study was to evaluate the measurement performance of the ACTS (Dutch, Italian, French, German and English language versions in patients with venous thromboembolism based on traditional psychometric methods. Methods ACTS Burdens and Benefits scale data from a large clinical trial (EINSTEIN DVT involving 1336 people with venous thromboembolism were analysed at both the scale and item level. Five key psychometric properties were examined using traditional psychometric methods: acceptability, scaling assumptions, reliability (including internal consistency reliability, test-retest reproducibility; validity (including known groups and discriminant validity; and responsiveness. These methods of examination underpin the US Food and Drug Administration recommendations for patient-reported outcome instrument evaluation. Results Overall, the 12-item ACTS Burdens scale and 3-item ACTS Benefits scale met the psychometric criteria evaluated at both item and scale levels, with the exception of some relatively minor issues in the Dutch language version, which were just below reliability criteria (i.e. alpha = 0.72, test-retest intraclass correlation = 0.79. A consistent finding from item-level evaluations of aggregate endorsement frequencies and skewness suggested that response scales may be improved by reducing the number of response options from five to four. Conclusions Both the ACTS Burdens and ACTS Benefits scales consistently satisfied traditional reliability and validity criteria across multiple language datasets, supporting it as a clinically useful patient

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  8. Experimental Validation of Methods for Prophylaxis against Deep Venous Thrombosis: A Review and Proposal

    Directory of Open Access Journals (Sweden)

    Paul S. Agutter

    2012-01-01

    Full Text Available The experimental procedure by which the valve cusp hypoxia (VCH hypothesis of the etiology of deep venous thrombosis (DVT was confirmed lends itself to testing of methods of prophylaxis. Similar animal experiments could end the present exclusive reliance on statistical analysis of data from large patient cohorts to evaluate prophylactic regimes. The reduction of need for such (usually retrospective analyses could enable rationally-based clinical trials of prophylactic methods to be conducted more rapidly, and the success of such trials would lead to decreased incidences of DVT-related mortality and morbidity. This paper reviews the VCH hypothesis (“VCH thesis”, following its corroboration and its implications for understanding DVT and its sequelae, and outlines the experimental protocol for testing prophylactic methods. The advantages and limitations of the protocol are briefly discussed.

  9. Non-invasive estimation of venous admixture: validation of a new formula.

    Science.gov (United States)

    Hope, D A; Jenkins, B J; Willis, N; Maddock, H; Mapleson, W W

    1995-05-01

    We have developed a computer program that estimates venous admixture (intra-pulmonary shunt) from four measurements: haemoglobin concentration, end-tidal carbon dioxide tension (PE'CO2), fractional inspired oxygen concentration (FIO2) and pulse oximetry (SpO2). The formula was tested on patients in an intensive therapy unit by using it to estimate shunt while it was measured simultaneously by a standard, invasive method. A total of 101 measurements were made in 29 patients. After correcting the systematic errors in the assumed differences between PE'CO2 and arterial PCO2, and between SpO2 and co-oximetrically measured SaO2, and correcting for a trend in the arteriovenous oxygen concentration difference (C(a-v))2) with shunt, the bias of the non-invasive minus invasive shunt differences was negligible, with no significant dependence on shunt. The limits of agreement were then +/- 16% shunt overall (+/- 13% within patients). When SaO2 was used instead of SpO2, the limits were +/- 11% (+/- 8% within patients).

  10. [Multicenter validation study of a questionnaire assessing patient satisfaction with and acceptance of totally-implanted central venous access devices].

    Science.gov (United States)

    Marcy, Pierre Yves; Dahlet, Christian; Brenet, Olivier; Yazbec, Gabriel; Dubois, Pierre Yves; Salm, Bernard; Fouche, Yves; Mari, Veronique; Montastruc, Marion; Lebrec, Nathalie; Ancel, Benoit; Paillocher, Nicolas; Dupoiron, Denis; Rangeard, Olivier; Michel, Cécile; Chateau, Yann; Ettaiche, Marc; Ferrero, Jean-Marc; Chamorey, Emmanuel

    2015-04-01

    Most cancer patients require a totally-implanted central venous access device (TIVAD) for their treatment. This was a prospective, multicenter, open study to: (i) develop and validate a French-language questionnaire dubbed QASICC (Questionnaire for Acceptance of and Satisfaction with Implanted Central Venous Catheter) assessing patient's satisfaction with and acceptance of their TIVAD; (ii) develop a mean score of patient's acceptance and satisfaction; (iii) look for correlation between QASICC score and TIVAD patient/tumor pathology/device characteristics. From 2011 November to 2012 December, the first version of the QASICC questionnaire that included 27 questions assessing seven dimensions was re-tested among 998 cancer patients in eleven French cancer hospitals (eight cancer research institutes and three university/general hospitals). The goal was: (i) to reduce the questionnaire item and dimension number (pertinency, saturation effect, item correlation); (ii) to assess its psychometric properties, demonstrate its validity and independency compared to (EORTC) QLQC30; (iii) to correlate clinical and pathological patient's/tumor's/TIVAD's parameters with the QASICC questionnaire score (the higher the overall score, the greater the acceptance and satisfaction). The questionnaire was administered to the patient 30 days (±15 days) after TIVAD's implantation. Among 998 questionnaires given to cancer patients, 658 were analyzed and 464 were fully assessed as there was no missing data. Time to fill-in the questionnaire was five minutes in 90% patients. Final QASICC tool included twenty-two questions assessing four homogeneous dimensions (65%

  11. Instrument validation for peripheral venous puncture with over-the-needle catheter

    Directory of Open Access Journals (Sweden)

    Aminna Kelly Almeida de Oliveira

    2015-05-01

    Full Text Available Objective: to validate an instrument for the assessment of the peripheral venipuncture technique with over-the-needle catheter. Methods: methodological, transversal study developed with 24 judge nurses, professors of the subject semiology and/or physical examination techniques, with at least 1 year of experience in those disciplines in three stages: preparation of checklist; submission to the judges for evaluation; and content validation through the application of the Kappa index. Results: out of the 26 items of the instrument, only 2 did not have Kappa index and content validity index within the established parameters. Out of these 24 items, 7 showed perfect concordance index, 10 great and 7 good. Conclusion: the instrument had representation and extension about the area of ​​interest.

  12. Vorticity visualization: phantom study for a new discriminant parameter in US elastography

    Science.gov (United States)

    Sosa-Cabrera, D.; Rodriguez-Florido, M. A.; Suarez-Santana, E.; Ruiz-Alzola, Juan

    2007-03-01

    Ultrasound elastography measures the elastic properties of soft tissues using ultrasound signals. The elastic problem can be analyzed with tensor signal processing. In this work, we propose a new interpretation of elastography through the deformation tensor and its decomposition into both the strain and vorticity tensors. Vorticity gives information about the rotation of the inclusions that might help in the discrimination between malign and benign tumors without using biopsy. Although clinical validation is needed, synthetic experiments present reliable results.

  13. An instrument for measuring health-related quality of life in patients with Deep Venous Thrombosis (DVT: development and validation of Deep Venous Thrombosis Quality of Life (DVTQOL questionnaire

    Directory of Open Access Journals (Sweden)

    Stigendal Lennart

    2004-06-01

    Full Text Available Abstract Background Few studies have evaluated patient-reported outcomes in connection with a primary event of deep venous thrombosis, partly due to a lack of disease-specific measures. The aim here was to develop a disease-specific health-related quality of life (HRQL measure, the deep venous thrombosis quality of life questionnaire (DVTQOL, for patients with recent exposition and treatment of proximal deep venous thrombosis. Methods A total of 121 consecutive outpatients (50 % males; mean age 61.2 ± 14 years treated with warfarin (Waran® for symptomatic proximal deep venous thrombosis were included in the study. Patients completed the SF-36, EQ-5D and the pilot version of the DVTQOL. Results Items having: high ceiling and floor effect, items with lower factor loadings than 0.50 and items loading in several factors were removed from the pilot version of DVTQOL. In addition, overlapping and redundant items identified by the Rasch analysis were excluded. The final DVTQOL questionnaire consists of 29 items composing six dimensions depicting problems with: emotional distress; symptoms (e.g. pain, swollen ankles, cramp, bruising; limitation in physical activity; hassle with coagulation monitoring; sleep disturbance; and dietary problems. The internal consistency reliability was high (alpha value ranged from 0.79 to 0.93. The relevant domains of the SF-36 and EQ-5D significantly correlated with DVTQOL, thereby confirming its construct validity. Conclusions The DVTQOL is a short and user-friendly instrument with good reliability and validity. Its test-retest reliability and responsiveness to change in clinical trials, however, must be explored.

  14. Elastography using multi-stream GPU: an application to online tracked ultrasound elastography, in-vivo and the da Vinci Surgical System.

    Directory of Open Access Journals (Sweden)

    Nishikant P Deshmukh

    Full Text Available A system for real-time ultrasound (US elastography will advance interventions for the diagnosis and treatment of cancer by advancing methods such as thermal monitoring of tissue ablation. A multi-stream graphics processing unit (GPU based accelerated normalized cross-correlation (NCC elastography, with a maximum frame rate of 78 frames per second, is presented in this paper. A study of NCC window size is undertaken to determine the effect on frame rate and the quality of output elastography images. This paper also presents a novel system for Online Tracked Ultrasound Elastography (O-TRuE, which extends prior work on an offline method. By tracking the US probe with an electromagnetic (EM tracker, the system selects in-plane radio frequency (RF data frames for generating high quality elastograms. A novel method for evaluating the quality of an elastography output stream is presented, suggesting that O-TRuE generates more stable elastograms than generated by untracked, free-hand palpation. Since EM tracking cannot be used in all systems, an integration of real-time elastography and the da Vinci Surgical System is presented and evaluated for elastography stream quality based on our metric. The da Vinci surgical robot is outfitted with a laparoscopic US probe, and palpation motions are autonomously generated by customized software. It is found that a stable output stream can be achieved, which is affected by both the frequency and amplitude of palpation. The GPU framework is validated using data from in-vivo pig liver ablation; the generated elastography images identify the ablated region, outlined more clearly than in the corresponding B-mode US images.

  15. Elastography Using Multi-Stream GPU: An Application to Online Tracked Ultrasound Elastography, In-Vivo and the da Vinci Surgical System

    Science.gov (United States)

    Deshmukh, Nishikant P.; Kang, Hyun Jae; Billings, Seth D.; Taylor, Russell H.; Hager, Gregory D.; Boctor, Emad M.

    2014-01-01

    A system for real-time ultrasound (US) elastography will advance interventions for the diagnosis and treatment of cancer by advancing methods such as thermal monitoring of tissue ablation. A multi-stream graphics processing unit (GPU) based accelerated normalized cross-correlation (NCC) elastography, with a maximum frame rate of 78 frames per second, is presented in this paper. A study of NCC window size is undertaken to determine the effect on frame rate and the quality of output elastography images. This paper also presents a novel system for Online Tracked Ultrasound Elastography (O-TRuE), which extends prior work on an offline method. By tracking the US probe with an electromagnetic (EM) tracker, the system selects in-plane radio frequency (RF) data frames for generating high quality elastograms. A novel method for evaluating the quality of an elastography output stream is presented, suggesting that O-TRuE generates more stable elastograms than generated by untracked, free-hand palpation. Since EM tracking cannot be used in all systems, an integration of real-time elastography and the da Vinci Surgical System is presented and evaluated for elastography stream quality based on our metric. The da Vinci surgical robot is outfitted with a laparoscopic US probe, and palpation motions are autonomously generated by customized software. It is found that a stable output stream can be achieved, which is affected by both the frequency and amplitude of palpation. The GPU framework is validated using data from in-vivo pig liver ablation; the generated elastography images identify the ablated region, outlined more clearly than in the corresponding B-mode US images. PMID:25541954

  16. Endoscopic ultrasound duplex scanning for measurement of portal venous flow. Validation against transit time ultrasound flowmetry in pigs

    DEFF Research Database (Denmark)

    Hansen, E F; Strandberg, C; Bendtsen, F

    1999-01-01

    with that of transit time ultrasound (TTU) in healthy pigs. The ability of EUS to detect changes in the portal venous flow after pharmacologic intervention was also investigated. METHODS: Six anaesthetized pigs were studied. Portal venous flow was measured simultaneously by EUS duplex scanning, using a Pentax FG-32UA......BACKGROUND: Endoscopic ultrasound (EUS) is a new technique that makes it possible to measure portal venous flow when transabdominal ultrasound fails. As the technique has not been evaluated previously, we compared simultaneous measurements of portal venous flow using EUS Doppler...... administration. RESULTS: Portal venous flow measured by EUS flowmetry and TTU flowmetry correlated significantly (R = 0.92, P flow after terlipressin measured by EUS and TTU...

  17. Liver elastography, comments on EFSUMB elastography guidelines 2013

    Science.gov (United States)

    Cui, Xin-Wu; Friedrich-Rust, Mireen; Molo, Chiara De; Ignee, Andre; Schreiber-Dietrich, Dagmar; Dietrich, Christoph F

    2013-01-01

    Recently the European Federation of Societies for Ultrasound in Medicine and Biology Guidelines and Recommendations have been published assessing the clinical use of ultrasound elastography. The document is intended to form a reference and to guide clinical users in a practical way. They give practical advice for the use and interpretation. Liver disease forms the largest section, reflecting published experience to date including evidence from meta-analyses with shear wave and strain elastography. In this review comments and illustrations on the guidelines are given. PMID:24151351

  18. Continuous monitoring of central venous oxygen saturation (Pediasat) in pediatric patients undergoing cardiac surgery: a validation study of a new technology.

    Science.gov (United States)

    Ranucci, Marco; Isgrò, Giuseppe; De La Torre, Teresa; Romitti, Federica; De Benedetti, Donatella; Carlucci, Concetta; Kandil, Hassan; Ballotta, Andrea

    2008-12-01

    Mixed venous oxygen saturation and central venous oxygen saturation are considered possible indicators of the adequacy of oxygen delivery with respect to the oxygen needs of critically ill adult and pediatric patients. The present study was aimed at validating the accuracy of a new technology (Pediasat central venous catheter) in providing a continuous measurement of the central venous oxygen saturation in pediatric patients. A prospective observational study. Thirty pediatric patients (age, 6 days-9 years) undergoing cardiac operations. Data obtained with the Pediasat during and after the operation were compared with simultaneously collected venous blood samples analyzed with standard laboratory techniques. A clinical research hospital. None. A Bland and Altman analysis was performed on 30 matched sets of data collected before cardiopulmonary bypass, during cardiopulmonary bypass, and during the intensive care unit stay. Before cardiopulmonary bypass, there was a bias of 0.003, with lower and upper limits of agreement, -5.84 and 5.84 (percentage error, 17.3%). During cardiopulmonary bypass, the bias was 0.57 and lower and upper limits of agreement were -7.7 and 8.7 (percentage error, 23.2%). At 2 hours after the arrival in the intensive care unit, the bias was -0.6 and the lower and upper limits of agreement were -8 and 6.8 (percentage error, 20.3%). Because of the minimal bias and the acceptable value of percentage error, the Pediasat may be considered as an accurate tool for the continuous measurement of the central venous oxygen saturation in neonates and pediatric patients during and after cardiac operations.

  19. Ultrasound Elastography Is Useful for Evaluation of Liver Fibrosis in Children

    DEFF Research Database (Denmark)

    Andersen, Sofie Bech; Ewertsen, Caroline; Carlsen, Jonathan Frederik

    2016-01-01

    was investigated in 14 studies and were comparable to those existing for adults. Twelve studies compared elastography with liver biopsy in children with liver disease and found that cirrhosis was correctly diagnosed, whereas it was more difficult to assess severe fibrosis correctly. For the distinction between no......OBJECTIVES: Adult studies have proven ultrasound elastography as a validated measure of liver fibrosis. The present study aimed to review the available literature on ultrasound elastography in children to evaluate the ability of the method to distinguish healthy from fibrotic liver tissue...... and investigate whether cutoff values for liver fibrosis in children have been established. METHODS: A literature search was performed in MEDLINE, EMBASE, the Cochrane Library, and Web of Science to identify studies on ultrasound elastography of the liver in children. Only original research articles in English...

  20. Endoscopic ultrasound duplex scanning for measurement of portal venous flow. Validation against transit time ultrasound flowmetry in pigs

    DEFF Research Database (Denmark)

    Hansen, Erik Feldager; Strandberg, C; Bendtsen, F

    1999-01-01

    BACKGROUND: Endoscopic ultrasound (EUS) is a new technique that makes it possible to measure portal venous flow when transabdominal ultrasound fails. As the technique has not been evaluated previously, we compared simultaneous measurements of portal venous flow using EUS Doppler...... with that of transit time ultrasound (TTU) in healthy pigs. The ability of EUS to detect changes in the portal venous flow after pharmacologic intervention was also investigated. METHODS: Six anaesthetized pigs were studied. Portal venous flow was measured simultaneously by EUS duplex scanning, using a Pentax FG-32UA...... echoendoscope connected to a Hitachi EUB 515-A ultrasound scanner, and by TTU with a Cardiomed CM 4000 flowmeter probe placed on the portal vein. Terlipressin, 1 mg, and placebo were administered in a blind, randomized, crossover design. Measurements were taken at base line and 30 min after each drug...

  1. Quasi-Static Ultrasound Elastography

    Science.gov (United States)

    Varghese, Tomy

    2010-01-01

    Elastography is a new imaging modality where elastic tissue parameters related to the structural organization of normal and pathological tissues are imaged. Basic principles underlying the quasi-static elastography concept and principles are addressed. The rationale for elastographic imaging is reinforced using data on elastic properties of normal and abnormal soft tissues. The several orders of magnitude difference between the elastic modulus of normal and abnormal tissues which is the primary contrast mechanism in elastographic imaging underlines the probability of success with this imaging modality. Recent advances enabling the clinical practice of elastographic imaging in real-time on clinical ultrasound systems is also discussed. In quasi-static elastography, radiofrequency echo signals acquired before and after a small (about 1%) of applied deformation are correlated to estimate tissue displacements. Local tissue displacement vector estimates between small segments of the pre- and post-deformation signals are estimated and the corresponding strain distribution imaged. Elastographic imaging techniques are based on the hypothesis that soft tissues deform more than stiffer tissue, and these differences can be quantified in images of the tissue strain tensor or the Young’s modulus. Clinical applications of quasi-static elastography have mushroomed over the last decade, with the most commonly imaged areas being the breast, prostate, thyroid, cardiac, treatment monitoring of ablation procedures and vascular imaging applications. PMID:20798841

  2. Building an open-source simulation platform of acoustic radiation force-based breast elastography.

    Science.gov (United States)

    Wang, Yu; Peng, Bo; Jiang, Jingfeng

    2017-03-07

    Ultrasound-based elastography including strain elastography, acoustic radiation force impulse (ARFI) imaging, point shear wave elastography and supersonic shear imaging (SSI) have been used to differentiate breast tumors among other clinical applications. The objective of this study is to extend a previously published virtual simulation platform built for ultrasound quasi-static breast elastography toward acoustic radiation force-based breast elastography. Consequently, the extended virtual breast elastography simulation platform can be used to validate image pixels with known underlying soft tissue properties (i.e. 'ground truth') in complex, heterogeneous media, enhancing confidence in elastographic image interpretations. The proposed virtual breast elastography system inherited four key components from the previously published virtual simulation platform: an ultrasound simulator (Field II), a mesh generator (Tetgen), a finite element solver (FEBio) and a visualization and data processing package (VTK). Using a simple message passing mechanism, functionalities have now been extended to acoustic radiation force-based elastography simulations. Examples involving three different numerical breast models with increasing complexity-one uniform model, one simple inclusion model and one virtual complex breast model derived from magnetic resonance imaging data, were used to demonstrate capabilities of this extended virtual platform. Overall, simulation results were compared with the published results. In the uniform model, the estimated shear wave speed (SWS) values were within 4% compared to the predetermined SWS values. In the simple inclusion and the complex breast models, SWS values of all hard inclusions in soft backgrounds were slightly underestimated, similar to what has been reported. The elastic contrast values and visual observation show that ARFI images have higher spatial resolution, while SSI images can provide higher inclusion-to-background contrast. In

  3. Building an open-source simulation platform of acoustic radiation force-based breast elastography

    Science.gov (United States)

    Wang, Yu; Peng, Bo; Jiang, Jingfeng

    2017-03-01

    Ultrasound-based elastography including strain elastography, acoustic radiation force impulse (ARFI) imaging, point shear wave elastography and supersonic shear imaging (SSI) have been used to differentiate breast tumors among other clinical applications. The objective of this study is to extend a previously published virtual simulation platform built for ultrasound quasi-static breast elastography toward acoustic radiation force-based breast elastography. Consequently, the extended virtual breast elastography simulation platform can be used to validate image pixels with known underlying soft tissue properties (i.e. ‘ground truth’) in complex, heterogeneous media, enhancing confidence in elastographic image interpretations. The proposed virtual breast elastography system inherited four key components from the previously published virtual simulation platform: an ultrasound simulator (Field II), a mesh generator (Tetgen), a finite element solver (FEBio) and a visualization and data processing package (VTK). Using a simple message passing mechanism, functionalities have now been extended to acoustic radiation force-based elastography simulations. Examples involving three different numerical breast models with increasing complexity—one uniform model, one simple inclusion model and one virtual complex breast model derived from magnetic resonance imaging data, were used to demonstrate capabilities of this extended virtual platform. Overall, simulation results were compared with the published results. In the uniform model, the estimated shear wave speed (SWS) values were within 4% compared to the predetermined SWS values. In the simple inclusion and the complex breast models, SWS values of all hard inclusions in soft backgrounds were slightly underestimated, similar to what has been reported. The elastic contrast values and visual observation show that ARFI images have higher spatial resolution, while SSI images can provide higher inclusion-to-background contrast

  4. Validating the utilisation of venous bicarbonate as a predictor of acute kidney injury in crush syndrome from sjambok injuries.

    Science.gov (United States)

    Skinner, David Lee; Laing, Grant L; Bruce, John; Biccard, Bruce; Muckart, David J J

    2017-04-25

    Crush injury secondary to sjambok beatings is a well-described phenomenon in southern Africa. Owing to a number of factors, it can result in acute kidney injury (AKI). In 1992, Muckart et al. described a risk stratification system using venous bicarbonate (VB) that can be used in the management of these patients. To validate this score in the modern era of AKI risk stratification. A retrospective study was performed on a local trauma database from June 2010 to December 2012. All patients with crush injury from sjambok/blunt instrument beatings were included in the analysis. VB was compared with the Kidney Disease Improving Global Outcomes scoring system for AKI. Serum base excess (BE) and creatine kinase were also examined as biomarkers. The endpoints were the need for renal replacement therapy (RRT) and mortality. Three hundred and ten patients were included. The overall mortality rate was 1.9%, 14.8% of patients had AKI, and 3.9% required RRT. Both VB and BE performed well in RRT prediction, with areas under the receiver operating characteristic curve of 0.847 (95% confidence interval (CI) 0.756 - 0.938; p<0.001) and 0.871 (95% CI 0.795 - 0.947; p<0.001), respectively. The sensitivity and specificity of BE were 83.3% and 80.2% at an optimal cut-point of -7.25 mmol/L, while those of VB were 83.3% and 79.5% at an optimal cut-point of 18.85 mmol/L. VB was significantly different across the AKI risk groups (p<0.001), in keeping with the original Muckart risk stratification system. The risk stratification score using VB is valid and should continue to be used as a tool in the management of patients with sjambok injuries. BE performs well in predicting the need for RRT, with a value of <-7.25 mmol/L indicating severe injury.

  5. Ultrasound elastography in patients with rectal cancer treated with chemoradiation

    DEFF Research Database (Denmark)

    Rafaelsen, S R; Vagn-Hansen, C; Sørensen, T

    2013-01-01

    OBJECTIVE: The current literature has described several predictive markers in rectal cancer patients treated with chemoradiation, but so far none of them have been validated for clinical use. The purpose of the present study was to compare quantitative elastography based on ultrasound measurements...... in the course of chemoradiation with tumor response based on T stage classification and the Mandard tumor regression grading (TRG). MATERIALS AND METHODS: We prospectively examined 31 patients with rectal cancer planned for high dose radiochemotherapy. The tumor and the mesorectal fat elasticity were measured...... using the Acoustic Radiation Force Impulse to generate information on the mechanical properties of the tissue. The objective quantitative elastography shear wave velocity was compared to the T stage classification and TRG. RESULTS: The baseline mean tumor elasticity was 3.13m/s. Two and six weeks after...

  6. Novel ultrasound elastography system for multifocal breast cancer assessment

    Science.gov (United States)

    Shavakh, Shadi; Fenster, Aaron; Samani, Abbas

    2012-03-01

    Elastography is a non-invasive imaging technique that images tissue stiffness. Given the well known association between tissue stiffness and cancer type, it can be used effectively for breast cancer detection and assessment. This study involves system development of a real-time ultrasound based elastography system designed for assessing multifocal breast cancer. This system is capable of imaging breast tissues absolute Young's Moduli. The imaging involves tissue mechanical stimulation, displacement and force data acquisition followed by Young's modulus reconstruction using a constrained full-inversion approach. This approach utilizes axial strain field and surface force data acquired by the elastography system via an iterative numerical process to construct the breast tissue Young's modulus. The strain field is obtained using an ultrasound machine equipped with an RF signal processing module. For force data acquisition, a system comprised of two load cells attached at the ultrasound system probe was employed. Each iteration of the reconstruction algorithm involves tissue stress calculation followed by tissue Young's modulus updating. To speed up the reconstruction process, a novel accelerated finite element method developed in our laboratory was used for stress calculation. To validate the proposed method, tissue-mimicking phantom studies were conducted. These studies showed promising results paving the way for further validation and application in a clinical setting.

  7. Elastography of the Thyroid Glands

    Energy Technology Data Exchange (ETDEWEB)

    Kwak, Jin Young [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2011-06-15

    Although the current resolution of ultrasound (US) has markedly improved the ability to detect nodules and it can be used to differentiate malignant thyroid nodules from benign thyroid nodules, gray scale US alone is not perfectly capable of making this differentiation. US elastography is a relatively novel dynamic technique that evaluates the degree of distortion of a tissue under the application of an external force and it is based on the principle that the softer parts of tissues deform more easily than do the harder parts under compression, thus allowing an objective determination of tissue consistency. This review provides the basic concepts of US elastography and the potential clinical applications and limitations for diagnosing thyroid nodules

  8. Quantitative micro-elastography: imaging of tissue elasticity using compression optical coherence elastography

    Science.gov (United States)

    Kennedy, Kelsey M.; Chin, Lixin; McLaughlin, Robert A.; Latham, Bruce; Saunders, Christobel M.; Sampson, David D.; Kennedy, Brendan F.

    2015-10-01

    Probing the mechanical properties of tissue on the microscale could aid in the identification of diseased tissues that are inadequately detected using palpation or current clinical imaging modalities, with potential to guide medical procedures such as the excision of breast tumours. Compression optical coherence elastography (OCE) maps tissue strain with microscale spatial resolution and can delineate microstructural features within breast tissues. However, without a measure of the locally applied stress, strain provides only a qualitative indication of mechanical properties. To overcome this limitation, we present quantitative micro-elastography, which combines compression OCE with a compliant stress sensor to image tissue elasticity. The sensor consists of a layer of translucent silicone with well-characterized stress-strain behaviour. The measured strain in the sensor is used to estimate the two-dimensional stress distribution applied to the sample surface. Elasticity is determined by dividing the stress by the strain in the sample. We show that quantification of elasticity can improve the ability of compression OCE to distinguish between tissues, thereby extending the potential for inter-sample comparison and longitudinal studies of tissue elasticity. We validate the technique using tissue-mimicking phantoms and demonstrate the ability to map elasticity of freshly excised malignant and benign human breast tissues.

  9. Quantitative micro-elastography: imaging of tissue elasticity using compression optical coherence elastography.

    Science.gov (United States)

    Kennedy, Kelsey M; Chin, Lixin; McLaughlin, Robert A; Latham, Bruce; Saunders, Christobel M; Sampson, David D; Kennedy, Brendan F

    2015-10-27

    Probing the mechanical properties of tissue on the microscale could aid in the identification of diseased tissues that are inadequately detected using palpation or current clinical imaging modalities, with potential to guide medical procedures such as the excision of breast tumours. Compression optical coherence elastography (OCE) maps tissue strain with microscale spatial resolution and can delineate microstructural features within breast tissues. However, without a measure of the locally applied stress, strain provides only a qualitative indication of mechanical properties. To overcome this limitation, we present quantitative micro-elastography, which combines compression OCE with a compliant stress sensor to image tissue elasticity. The sensor consists of a layer of translucent silicone with well-characterized stress-strain behaviour. The measured strain in the sensor is used to estimate the two-dimensional stress distribution applied to the sample surface. Elasticity is determined by dividing the stress by the strain in the sample. We show that quantification of elasticity can improve the ability of compression OCE to distinguish between tissues, thereby extending the potential for inter-sample comparison and longitudinal studies of tissue elasticity. We validate the technique using tissue-mimicking phantoms and demonstrate the ability to map elasticity of freshly excised malignant and benign human breast tissues.

  10. Venous thrombosis: an overview

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, C.W.

    1986-07-01

    Venous thromboembolic disease contributes to morbidity and mortality in certain groups of hospitalized patients, particularly those who have undergone surgery. Although principles of treatment have changed relatively little during the past 20 years, significant advances have been made in the diagnosis of deep vein thrombosis (DVT). Venography, once the only reliable diagnostic technique, has been largely replaced by noninvasive tests: impedance plethysmography, venous Doppler, /sup 125/I-radiofibrinogen-uptake test, and phleborheography. Virchow's triad of stasis, vessel injury, and hypercoagulability remains a valid explanation of the pathogenesis of thrombus formation, but laboratory and clinical data have refined our knowledge of how these factors interact to result in clinically significant disease. Knowledge of the natural history of venous thrombosis, plus heightened awareness of the long-term morbidity and expense associated with the postphlebitic syndrome, have led to increased interest in preventing DVT. Clinically and economically, venous thrombosis is best managed by prevention. 61 references.

  11. SWE elastography in assessment of liver fibrosis

    Directory of Open Access Journals (Sweden)

    Urszula Zaleska-Dorobisz

    2015-02-01

    Full Text Available Liver fibrosis is a relatively common consequence of chronic liver diseases, especially chronic viral hepatitis B and C. Biopsy still remains the gold standard in the assessment of liver fibrosis. However, due to its invasiveness and possible complications, less or even non-invasive methods are being developed, e.g. using biochemical parameters (Fibrotest or elastography. Elastography is a new diagnostic tool that aims to evaluate stiffness of the tissues. Elastography techniques that are used in the assessment of liver fibrosis are transient elastography (TE, acoustic radiation force impulse (ARFI and shear-wave elastography (SWE. SWE is a novel real-time two-dimensional elastography technique, which allows one to estimate stiffness quantitatively in kilopascals (kPa. Moreover, lapping elastography over regular B-mode allows precise choice of the region of interest. Therefore SWE creates the opportunity for accurate assessment of liver fibrosis. In this paper we describe processes leading to liver fibrosis as well as methods of liver fibrosis assessment, e.g. liver biopsy, biochemical tests or elastography. The main goal of this paper is to present the SWE technique, its role in liver fibrosis assessment and a short review of the most important clinical studies on SWE. We also present several examples of SWE examinations performed on patients with different stages of liver fibrosis – F0 to F4 on the METAVIR scale.

  12. Ultrasound Elastography in Breast Cancer Diagnosis

    DEFF Research Database (Denmark)

    Carlsen, J.; Ewertsen, C; Sletting, S

    2015-01-01

    Ultrasound elastography is an established method for characterization of focal lesions in the breast. Different techniques and analyses of the images may be used for the characterization. This article addresses the use of ultrasound elastography in breast cancer diagnosis. In the first part...

  13. [Venous ulcer].

    Science.gov (United States)

    Böhler, Kornelia

    2016-06-01

    Venous disorders causing a permanent increase in venous pressure are by far the most frequent reason for ulcers of the lower extremity. With a prevalence of 1 % in the general population rising to 4 % in the elderly over 80 and its chronic character, 1 % of healthcare budgets of the western world are spent on treatment of venous ulcers. A thorough investigation of the underlying venous disorder is the prerequisite for a differenciated therapy. This should comprise elimination of venous reflux as well as local wound management. Chronic ulcers can successfully be treated by shave therapy and split skin grafting. Compression therapy is a basic measure not only in venous ulcer treatment but also in prevention of ulcer recurrence. Differential diagnosis which have to be considered are arterial ulcers, vasculitis and neoplasms.

  14. Translation, cultural adaptation to Brazil and validation of the Venous leg ulcer quality of life questionnaire (VLU-QoL-Br).

    Science.gov (United States)

    Araújo, Renata Boldrin de; Fortes, Maria Rita Parise; Abbade, Luciana Patrícia Fernandes; Miot, Hélio Amante

    2014-01-01

    Translating the Venous leg ulcer quality of life questionnaire (VLU-QoL), and culturally adapting it to Brazilian Portuguese and validate it with patients at the Hospital das Clínicas of the Botucatu Medical School - Unesp. The questionnaire was translated by a professional translator and two dermatologists specialized in the area of venous ulcers (VU), reformulated in a meeting of the three translators. The construct (VLU-QoL-Br) was submitted to pre-interviews with ten VU patients for adaptation of the language. Subsequently, it was applied to patients at the HC-Unesp, and for test-retest reliability for verification of its reproducibility. 82 patients were evaluated, with 56 (68%) women. The age average was 67.3 years. The questionnaire was translated, adapted and applied to the patients. The construct presented high internal consistency (alpha = 0.94) and adequate item-total correlation. When the 32 retests were evaluated, an intra-class correlation was noted for concordance of 0.78 (ptranslation, adaptation and validation of the VLU-QoL-Br questionnaire were concluded, demonstrating good psychometric performance, and enabling its clinical use in Brazil. It is important to evaluate its performance in other regions and different samples of individuals.

  15. Shear-wave elastography of the liver and spleen identifies clinically significant portal hypertension

    DEFF Research Database (Denmark)

    Jansen, Christian; Bogs, Christopher; Verlinden, Wim

    2017-01-01

    BACKGROUND & AIMS: Clinically significant portal hypertension (CSPH) is associated with severe complications and decompensation of cirrhosis. Liver stiffness measured either by transient elastography (TE) or Shear-wave elastography (SWE) and spleen stiffness by TE might be helpful in the diagnosis...... correlate with portal pressure and can both be used as a non-invasive method to investigate CSPH. Even though external validation is still missing, these algorithms to rule-out and rule-in CSPH using sequential SWE of liver and spleen might change the clinical practice....

  16. Rescaled Local Interaction Simulation Approach for Shear Wave Propagation Modelling in Magnetic Resonance Elastography

    Science.gov (United States)

    Packo, P.; Staszewski, W. J.; Uhl, T.

    2016-01-01

    Properties of soft biological tissues are increasingly used in medical diagnosis to detect various abnormalities, for example, in liver fibrosis or breast tumors. It is well known that mechanical stiffness of human organs can be obtained from organ responses to shear stress waves through Magnetic Resonance Elastography. The Local Interaction Simulation Approach is proposed for effective modelling of shear wave propagation in soft tissues. The results are validated using experimental data from Magnetic Resonance Elastography. These results show the potential of the method for shear wave propagation modelling in soft tissues. The major advantage of the proposed approach is a significant reduction of computational effort. PMID:26884808

  17. Shear wave induced resonance elastography of spherical masses with polarized torsional waves.

    Science.gov (United States)

    Henni, Anis Hadj; Schmitt, Cédric; Trop, Isabelle; Cloutier, Guy

    2012-03-26

    Shear Wave Induced Resonance (SWIR) is a technique for dynamic ultrasound elastography of confined mechanical inclusions. It was developed for breast tumor imaging and tissue characterization. This method relies on the polarization of torsional shear waves modeled with the Helmholtz equation in spherical coordinates. To validate modeling, an in vitro set-up was used to measure and image the first three eigenfrequencies and eigenmodes of a soft sphere. A preliminary in vivo SWIR measurement on a breast fibroadenoma is also reported. Results revealed the potential of SWIR elastography to detect and mechanically characterize breast lesions for early cancer detection.

  18. Rescaled Local Interaction Simulation Approach for Shear Wave Propagation Modelling in Magnetic Resonance Elastography

    Directory of Open Access Journals (Sweden)

    Z. Hashemiyan

    2016-01-01

    Full Text Available Properties of soft biological tissues are increasingly used in medical diagnosis to detect various abnormalities, for example, in liver fibrosis or breast tumors. It is well known that mechanical stiffness of human organs can be obtained from organ responses to shear stress waves through Magnetic Resonance Elastography. The Local Interaction Simulation Approach is proposed for effective modelling of shear wave propagation in soft tissues. The results are validated using experimental data from Magnetic Resonance Elastography. These results show the potential of the method for shear wave propagation modelling in soft tissues. The major advantage of the proposed approach is a significant reduction of computational effort.

  19. Noise reduction for ultrasonic elastography using transmit-side frequency compounding: a preliminary study.

    Science.gov (United States)

    Cui, Shaoguo; Liu, Dong C

    2011-03-01

    Ultrasonic elastography is an imaging technique providing information about the relative stiffness of biological tissues. In general, elastography suffers from noise artifacts, which degrade lesion detectability and increase the likelihood of misdiagnosis. This paper proposes a method called transmit- side frequency compounding for elastography (TSFC). Beamforming is modified to transmit frames with N alternating center frequencies. Pairs of frames with the same center frequency are used to calculate sub-elastograms that are then averaged to produce one compounded elastogram. Simulation results based on an uniformly elastic tissue model demonstrate the decorrelation among sub-elastograms and the improvement in elastographic signal-to-noise ratio (SNRe) achieved by compounding sub-elastograms. An elastic phantom experiment further validates the noise reduction obtained by the proposed technique.

  20. Real-Time Elastography of the Prostate

    Directory of Open Access Journals (Sweden)

    D. Junker

    2014-01-01

    Full Text Available Palpation of organs is one of the oldest clinical examination techniques, for instance, if you think of the palpation of the breast or the digital rectal examination of the prostate, where hard palpable regions are suspicious for cancer. This is the basic principle of real-time elastography, an ultrasound technique, which is able to visualise tissue elasticity. Since prostate cancer features an increased stiffness due to the higher cell and vessel density than the normal surrounding tissue, real-time elastography has been used for several years for prostate cancer detection. This review introduces the different techniques of ultrasound elastography and furthermore summarises its limitations and potentials.

  1. Optical coherence elastography in ophthalmology.

    Science.gov (United States)

    Kirby, Mitchell A; Pelivanov, Ivan; Song, Shaozhen; Ambrozinski, Łukasz; Yoon, Soon Joon; Gao, Liang; Li, David; Shen, Tueng T; Wang, Ruikang K; O'Donnell, Matthew

    2017-12-01

    Optical coherence elastography (OCE) can provide clinically valuable information based on local measurements of tissue stiffness. Improved light sources and scanning methods in optical coherence tomography (OCT) have led to rapid growth in systems for high-resolution, quantitative elastography using imaged displacements and strains within soft tissue to infer local mechanical properties. We describe in some detail the physical processes underlying tissue mechanical response based on static and dynamic displacement methods. Namely, the assumptions commonly used to interpret displacement and strain measurements in terms of tissue elasticity for static OCE and propagating wave modes in dynamic OCE are discussed with the ultimate focus on OCT system design for ophthalmic applications. Practical OCT motion-tracking methods used to map tissue elasticity are also presented to fully describe technical developments in OCE, particularly noting those focused on the anterior segment of the eye. Clinical issues and future directions are discussed in the hope that OCE techniques will rapidly move forward to translational studies and clinical applications. (2017) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).

  2. Characterizing vulnerable plaque features with intravascular elastography.

    NARCIS (Netherlands)

    Schaar, J.A.; Korte, C.L. de; Mastik, F.; Strijder, C.; Pasterkamp, G.; Boersma, E.; Serruys, P.W.; Steen, A.F.W. van der

    2003-01-01

    BACKGROUND: In vivo detection of vulnerable plaques is presently limited by a lack of diagnostic tools. Intravascular ultrasound elastography is a new technique based on intravascular ultrasound and has the potential to differentiate between different plaques phenotypes. However, the predictive

  3. Venous Ulcers

    Science.gov (United States)

    Caprini, J.A.; Partsch, H.; Simman, R.

    2013-01-01

    Venous leg ulcers are the most frequent form of wounds seen in patients. This article presents an overview on some practical aspects concerning diagnosis, differential diagnosis and treatment. Duplex ultrasound investigations are essential to ascertain the diagnosis of the underlying venous pathology and to treat venous refluxes. Differential diagnosis includes mainly other vascular lesions (arterial, microcirculatory causes), hematologic and metabolic diseases, trauma, infection, malignancies. Patients with superficial venous incompetence may benefit from endovenous or surgical reflux abolition diagnosed by Duplex ultrasound. The most important basic component of the management is compression therapy, for which we prefer materials with low elasticity applied with high initial pressure (short-stretch bandages and Velcro-strap devices). Local treatment should be simple, absorbing and not sticky dressings keeping adequate moisture balance after debridement of necrotic tissue and biofilms are preferred. After the ulcer is healed compression therapy should be continued in order to prevent recurrence. PMID:26236636

  4. Non-Invasive Method for the Rapid Assessment of Central Venous Pressure: Description and Validation by a Single Examiner

    Directory of Open Access Journals (Sweden)

    Zidulka, Arnold

    2008-11-01

    Full Text Available Objectives: This study describes a means of assessing the external jugular venous pressure (JVP as an indicator of normal or elevated central venous pressure (CVP.Methods: Intensive care unit patients having CVP monitoring were examined. With patients in bed, the external jugular vein (EJV was occluded at the base of the neck and observed to distend. The occlusion was then removed and the vein observed for collapse. Complete collapse was hypothesized to indicate a non-elevated CVP (≤8cm of water. In those patients whose EJV collapsed incompletely, the vein was then occluded with the finger near the angle of the jaw. With the occlusion maintained, the vein was milked downwards with the other hand to cause its emptying and was then observed for filling from below. Filling from below was hypothesized to indicate an elevated CVP (>8cm of water.Results: In 12 of the 40 patients examined, the EJV could not be assessed (EJV not seen at all: 5, and difficult to visualize: 7. For the remaining 28 patients, 11 had a CVP > 8 cm, while 17 had a CVP of < 8. EJV assessment was 100% accurate (95% Confidence Interval 88-100 in predicting whether or not a patient’s CVP was greater or less than 8 cm of water.Conclusion: EJV assessment, when visible, is accurate to clinically assess a patient’s CVP in the hands of the author. Further studies are needed to see if they are reproducible by other observer.[WestJEM. 2008;9:201-205.

  5. Translation, cultural adaptation to Brazil and validation of the venous leg ulcer quality of life questionnaire (VLU-QoL-Br

    Directory of Open Access Journals (Sweden)

    Renata Boldrin de Araújo

    2014-06-01

    Full Text Available Objective: translating the Venous leg ulcer quality of life questionnaire (VLU-QoL, and culturally adapting it to Brazilian Portuguese and validate it with patients at the Hospital das Clínicas of the Botucatu Medical School - Unesp. Methods: the questionnaire was translated by a professional translator and two dermatologists specialized in the area of venous ulcers (VU, reformulated in a meeting of the three translators. The construct (VLU-QoL-Br was submitted to pre-interviews with ten VU patients for adaptation of the language. Subsequently, it was applied to patients at the HC-Unesp, and for test-retest reliability for verification of its reproducibility. Results: 82 patients were evaluated, with 56 (68% women. The age average was 67.3 years. The questionnaire was translated, adapted and applied to the patients. The construct presented high internal consistency (alpha = 0.94 and adequate item-total correlation. When the 32 retests were evaluated, an intra-class correlation was noted for concordance of 0.78 (p<0.01, indicating good reproducibility of the construct. The confirmatory factor analysis corroborated the dimensions of the original questionnaire: activities, psychologies, and symptoms. VLU-QoL-Br scores were associated, independently, to the total area of the ulcers and a lower education level of the subjects (p<0.01. Conclusion: the translation, adaptation and validation of the VLU-QoL-Br questionnaire were concluded, demonstrating good psychometric performance, and enabling its clinical use in Brazil. It is important to evaluate its performance in other regions and different samples of individuals.

  6. What is to be done when transient elastography is not feasible?

    Directory of Open Access Journals (Sweden)

    Raluca Lupusoru

    2016-12-01

    Full Text Available OBJECTIVES AND BACKGROUND The aim of this study was to find an alternative to Transient Elastography when its’ application is impossible or when no valid and reliable measurements can be obtained through its usage. MATERIALS AND METHODS Liver stiffness values were assessed with transient elastography [TE- (Fibroscan], 2D shear wave elastography (SuperSonic Shear Imaging-SSI and point shear wave elastography (pSWE using VTQ and ElastPQ, in a cohort of 90 patients with chronic liver diseases. With the help of linear regression, we made a multivariate analysis in order to test the relationship between TE and the other three methods (ElastPQ, SSI, VTQ. Given the very well correlated factors, we consider them predictors for our model. RESULTS The model conducted with all the used factorsElastPQ+SSI+VTQ compared with TE explained the 90.7% of the model variability (R=0.907. We tempted the probability to exclude the factors one by one. SSI+VTQ explained 90% of the model variability (R=0.90. ElastPQ+VTQ explained 77% of the model variability (R=0.77 and SSI+ElastPQ explained 89% of the model variability (R=0.89. CONCLUSIONS SSI in combination with ElastPQ or VTQ is as good as the TE single use. Therefore, these combinations can be applied when TE can’t be performed or is not valid. REFERENCES 1.Tsochatzis EA el al,.Elastography for the diagnosis of severity of fibrosis in chronic liver disease: a meta-analysis of diagnostic accuracy. J Hepatology. 2011;54:650-9. 2.Nierhoff J et.al . The efficiency of acoustic radiation force imaging for the staging of liver fibrosis: a meta-analysisEurRadiol. 2013;23:3040-53. 3.Ferraioli G et al. Performace of ElastPq Shear Wave Elastography Technique for Assessing Fibrosis in Chronic Vira Hepatitis. J. Hepatology. 2013;58:S7. 4.Herrmann E et al. 2D-shear wave elastography is equivalent or superior to transient elastography for liver fibrosis assessment: an individual patient data based meta-analysis . EASL 2015

  7. Practice guideline for the performance of breast ultrasound elastography

    Directory of Open Access Journals (Sweden)

    Su Hyun Lee

    2014-01-01

    Full Text Available

    Ultrasound (US elastography is a valuable imaging technique for tissue characterization. Two main types of elastography, strain and shear-wave, are commonly used to image breast tissue. The use of elastography is expected to increase, particularly with the increased use of US for breast screening. Recently, the US elastographic features of breast masses have been incorporated into the 2nd edition of the Breast Imaging Reporting and Data System (BI-RADS US lexicon as associated findings. This review suggests practical guidelines for breast US elastography in consensus with the Korean Breast Elastography Study Group, which was formed in August 2013 to perform a multicenter prospective study on the use of elastography for US breast screening. This article is focused on the role of elastography in combination with B-mode US for the evaluation of breast masses. Practical tips for adequate data acquisition and the interpretation of elastography results are also presented.

  8. Association between kidney intracapsular pressure and ultrasound elastography.

    Science.gov (United States)

    Kashani, Kianoush B; Mao, Shennen A; Safadi, Sami; Amiot, Bruce P; Glorioso, Jaime M; Lieske, John C; Nyberg, Scott L; Zhang, Xiaoming

    2017-10-19

    Kidney congestion is a common pathophysiologic pathway of acute kidney injury (AKI) in sepsis and heart failure. There is no noninvasive tool to measure kidney intracapsular pressure (KIP) directly. We evaluated the correlation of KIP with kidney elasticity measured by ultrasound surface wave elastography (USWE). We directly measured transcatheter KIP in three pigs at baseline and after bolus infusion of normal saline, norepinephrine, vasopressin, dopamine, and fenoldopam; infiltration of 2-L peritoneal dialysis solution in the intra-abdominal space; and venous, arterial, and ureteral clamping. KIP was compared with USWE wave speed. Only intra-abdominal installation of peritoneal dialysis fluid was associated with significant change in KIP (mean (95% CI) increase, 3.7 (3.2-4.2)] mmHg; P < .001). Although intraperitoneal pressure and KIP did not differ under any experimental condition, bladder pressure was consistently and significantly greater than KIP under all circumstances (mean (95% CI) bladder pressure vs. KIP, 3.8 (2.9-4.) mmHg; P < .001). USWE wave speed significantly correlated with KIP (adjusted coefficient of determination, 0.71; P < .001). Estimate (95% CI) USWE speed for KIP prediction stayed significant after adjustment for KIP hypertension (-0.8 (- 1.4 to - 0.2) m/s; P = .008) whereas systolic and diastolic blood pressures were not significant predictors of KIP. In a pilot study of the swine model, we found ultrasound surface wave elastography speed is significantly correlated with transcatheter measurement of kidney intracapsular and intra-abdominal pressures, while bladder pressure overestimated kidney intracapsular pressure.

  9. Shear wave elastography for localization of prostate cancer lesions and assessment of elasticity thresholds: implications for targeted biopsies and active surveillance protocols.

    Science.gov (United States)

    Boehm, Katharina; Salomon, Georg; Beyer, Burkhard; Schiffmann, Jonas; Simonis, Kathrin; Graefen, Markus; Budaeus, Lars

    2015-03-01

    Shear wave elastography allows the detection of cancer by using focused ultrasound pulses for locally deforming tissue. The differences in tissue elasticity and stiffness have been used increasingly in breast cancer imaging and help detect potential tumor lesions in the prostate. In this study we localized prostate cancer lesions using shear wave elastography before radical prostatectomy and assessed the examiner independent elasticity threshold for cancer foci detection. Shear wave elastography scanning of the whole prostate was performed before radical prostatectomy in 60 consecutive patients with high, intermediate and low risk disease. Localization of suspected lesions and density threshold (kPa) were recorded in up to 12 areas and resulted in 703 different fields. Shear wave elastography findings were correlated with final pathology. Initially 381 areas were used to establish shear wave elastography cutoffs (development cohort 32 patients). Subsequently these cutoffs were validated in 322 areas (validation cohort 28 patients). Using shear wave elastography significant differences were recorded for the elasticity of benign tissue vs prostate cancer nodules at 42 kPa (range 29 to 71.3) vs 88 kPa (range 54 to 132) (all p <0.001). Median cancer lesion diameter was 26 mm (range 18 to 41). Applying the most informative cutoff of 50 kPa to the validation cohort resulted in 80.9% and 69.1% sensitivity and specificity, respectively, and 74.2% accuracy for detecting cancer nodules based on final pathological finding. The corresponding positive and negative predictive values were 67.1% and 82.2%, respectively. Shear wave elastography allows the identification of cancer foci based on shear wave elastography differences. Moreover, reliable cutoffs for this approach can be established, allowing examiner independent localization of prostate cancer foci. Copyright © 2015 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights

  10. The emergence of optical elastography in biomedicine

    Science.gov (United States)

    Kennedy, Brendan F.; Wijesinghe, Philip; Sampson, David D.

    2017-04-01

    Optical elastography, the use of optics to characterize and map the mechanical properties of biological tissue, involves measuring the deformation of tissue in response to a load. Such measurements may be used to form an image of a mechanical property, often elastic modulus, with the resulting mechanical contrast complementary to the more familiar optical contrast. Optical elastography is experiencing new impetus in response to developments in the closely related fields of cell mechanics and medical imaging, aided by advances in photonics technology, and through probing the microscale between that of cells and whole tissues. Two techniques -- optical coherence elastography and Brillouin microscopy -- have recently shown particular promise for medical applications, such as in ophthalmology and oncology, and as new techniques in cell mechanics.

  11. Transient elastography for liver fibrosis diagnosis

    DEFF Research Database (Denmark)

    Andersen, Ellen Sloth; Christensen, Peer Brehm; Weis, Nina

    2009-01-01

    Liver biopsy is considered the "golden standard" for assessment of hepatic fibrosis. However, the procedure has limitations because of inconvenience and rare but serious complications as bleeding. Furthermore, sampling errors are frequent, and interobserver variability often poses problems....... Recently, a modified ultrasound scanner (transient elastography) has been developed to assess fibrosis. The device measures liver elasticity, which correlates well with the degree of fibrosis. Studies have shown that transient elastography is more accurate in diagnosing cirrhosis than minor to moderate...... to be a valuable diagnostic procedure and follow-up of patients with chronic liver diseases....

  12. Sonographic Elastography of the Thyroid Gland.

    Science.gov (United States)

    Menzilcioglu, Mehmet Sait; Duymus, Mahmut; Avcu, Serhat

    2016-01-01

    Thyroid gland disorders include benign and malignant thyroid nodules and diffuse thyroid disorders. The incidence of malignant thyroid nodules is low and the prognosis is good. The diagnosis of thyroid cancer and diffuse parenchymal disorders is generally based on clinical manifestations and histopathological evaluation. Ultrasonography has its place in the diagnostics and follow-up of thyroid disorders. Ultrasonographic elastography is a new, developing method that shows increase in clinical practice. In this study, we aimed to review the data on thyroid ultrasound elastography.

  13. Clinical applications of transient elastography

    Directory of Open Access Journals (Sweden)

    Kyu Sik Jung

    2012-06-01

    Full Text Available Chronic liver disease represents a major public health problem, accounting for significant morbidity and mortality worldwide. As prognosis and management depend mainly on the amount and progression of liver fibrosis, accurate quantification of liver fibrosis is essential for therapeutic decision-making and follow-up of chronic liver diseases. Even though liver biopsy is the gold standard for evaluation of liver fibrosis, non-invasive methods that could substitute for invasive procedures have been investigated during past decades. Transient elastography (TE, FibroScan® is a novel non-invasive method for assessment of liver fibrosis with chronic liver disease. TE can be performed in the outpatient clinic with immediate results and excellent reproducibility. Its diagnostic accuracy for assessment of liver fibrosis has been demonstrated in patients with chronic viral hepatitis; as a result, unnecessary liver biopsy could be avoided in some patients. Moreover, due to its excellent patient acceptance, TE could be used for monitoring disease progression or predicting development of liver-related complications. This review aims at discussing the usefulness of TE in clinical practice.

  14. Ultrasound-based transient elastography compared to magnetic resonance elastography in soft tissue-mimicking gels

    Energy Technology Data Exchange (ETDEWEB)

    Oudry, Jennifer; Vappou, Jonathan; Willinger, Remy [Institut de mecanique des fluides et des solides, CNRS-Universite Louis Pasteur, UMR 7507, Strasbourg (France); Choquet, Philippe; Constantinesco, Andre [Service de Biophysique et Medecine Nucleaire, CHU Hautepierre, UMR 7507, Strasbourg (France); Sandrin, Laurent [Echosens, Research and Development Department, Paris (France)], E-mail: jennifer.oudry@echosens.com, E-mail: jvappou@imfs.u-strasbg.fr, E-mail: philippe.choquet@chru-strasbourg.fr, E-mail: willi@imfs.u-strasbg.fr, E-mail: laurent.sandrin@echosens.com, E-mail: andre.constantinesco@chru-strasbourg.fr

    2009-11-21

    Ultrasound-based transient elastography (TE) and magnetic resonance elastography (MRE) are increasingly used methods for the clinical evaluation of soft tissue mechanical properties and their alteration under diseased conditions. This study proposes a comparison between magnetic resonance elastography (MRE) and ultrasound-based transient elastography (TE). Both methods were tested on the same soft tissue-mimicking gels in a common frequency range in order to allow for direct quantitative comparison. For the four gels tested, relatively good agreement was found between the shear moduli measured by both methods, with an averaged relative difference of 23%. This study demonstrates that under the assumption of homogeneous media that are significantly more elastic than viscous, quantitative results obtained by both methods are comparable.

  15. Strain Elastography Evaluation of Rectal Tumors

    DEFF Research Database (Denmark)

    Waage, J. E. R.; Rafaelsen, S. R.; Borley, N. R.

    2015-01-01

    on two separate occasions. Observers were blinded to all clinical information except the circumferential location of the tumor. A continuous visual analog scale (VAS) and a categorical scale (W-score) were used for elastography evaluation. ERUS loops were T-staged according to the TNM classification...

  16. Intravascular elastography: from bench to bedside.

    NARCIS (Netherlands)

    Korte, C.L. de; Schaar, J.A.; Mastik, F.; Serruys, P.W.; Steen, A.F.W. van der

    2003-01-01

    An unstable lesion may rupture and cause an acute thrombotic reaction. These lesions contain a large lipid pool covered by a thin fibrous cap. The stress in the cap increased with decreasing thickness and increasing macrophage infiltration. Intravascular ultrasound (IVUS) elastography might be an

  17. Cervical elastography during pregnancy: clinical perspectives

    Directory of Open Access Journals (Sweden)

    Swiatkowska-Freund M

    2017-04-01

    Full Text Available Malgorzata Swiatkowska-Freund, Krzysztof Preis Department of Obstetrics, Medical University of Gdansk, Gdansk, Poland Abstract: Uterine cervix is a part of the uterus responsible for maintaining pregnancy till term. As long as the cervix remains long and firm and its internal orifice (os is closed, it can withstand enlargement of the uterine contents and resultant growing pressure. Mechanical properties of the cervix change during pregnancy; the cervix ripens prior to delivery, then effaces and dilates with contractions of the uterus. Ripening of the cervix can be assessed using the Bishop score and ultrasonographically determined length of the cervical canal and internal os. Consistency is one of the cervical properties that change during the course of the maturation process. Until recently, cervical consistency has been assessed only manually, but in 2007, the first report on elastographic imaging of the cervix during pregnancy has been published. Elastography presents the ability of a tissue to deform under pressure. The softer the tissue, the easier it changes its shape. Different methods of elastography are used – static, when tissue displacement in response to manual compression or physiological movements of vessels is measured, or dynamic, when the speed of shear wave propagation is determined. Irrespective of the method, elastography provides information on the internal os stiffness; this parameter, impossible for manual assessment, was shown to correlate with pregnancy outcome and is a strong predictor of preterm delivery or successful labor induction. Although elastography seems to be a highly promising diagnostic option, still no consensus has been reached regarding an optimal method for uterine cervix assessment, and virtually all previous studies of various elastographic methods produced highly satisfactory results. Future studies need to identify the most promising and objective elastographic method which may serve as a novel

  18. Limitations of Elastography Based Prostate Biopsy.

    Science.gov (United States)

    Schiffmann, Jonas; Grindei, Mircea; Tian, Zhe; Yassin, Dany-Jan; Steinwender, Tobias; Leyh-Bannurah, Sami-Ramzi; Randazzo, Marco; Kwiatkowski, Maciej; Karakiewicz, Pierre I; Hammerer, Peter; Manka, Lukas

    2016-06-01

    The role of elastography in patients initially and at repeat prostate biopsy is still indeterminate. The existing literature is sparse and controversial. We studied patients who underwent elastography based and systematic biopsy between October 2009 and February 2015 at Braunschweig Prostate Cancer Center. Patients were separated according to first vs repeat biopsy setting. Each prostate sextant was considered an individual case. The sensitivity, specificity, positive and negative predictive values, and accuracy of elastography to predict biopsy results were analyzed. The 95% CIs were determined by bootstrapping analysis of 2,000 samples. Overall 679 men and a total of 4,074 sextants were identified. Of the 679 men 160 (23.6%) underwent first biopsy and 519 (76.4%) underwent repeat biopsy. In the 160 men at first biopsy sensitivity was 18.0% (95% CI 14.5-21.3), specificity was 87.7% (95% CI 85.3-89.9), positive predictive value was 36.6% (95% CI 28.4-45.4), negative predictive value was 73.0% (95% CI 67.5-77.9) and accuracy was 67.9% (95% CI 63.4-72.2). Results in 519 men (76.4%) at repeat biopsy were 19.8% (95% CI 16.0-23.7), 90.9% (95% CI 89.9-91.9), 20.1% (95% CI 15.8-24.8), 90.7% (95% CI 89.0-92.3) and 83.5% (95% CI 81.6-85.2), respectively. We found limited reliability of elastography prediction at prostate biopsy in patients at first and repeat biopsies. Based on our analyses we cannot recommend a variation of well established systematic biopsy patterns or a decrease in biopsy cores based on elastography. Copyright © 2016 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  19. Ultrasound elastography for evaluation of cervical lymph nodes

    Directory of Open Access Journals (Sweden)

    Young Jun Choi

    2015-07-01

    Full Text Available Ultrasound (US elastography has been introduced as a noninvasive imaging technique for evaluating cervical lymph nodes. US elastography techniques include strain elastography and shear wave-based elastography. The application of this technique is based on the fact that stiff tissues tend to deform less and show less strain than compliant tissues when the same force is applied. In general, metastatic lymph nodes demonstrate higher stiffness than benign lymph nodes. Overall, preliminary studies suggest that US elastography may be useful in differentiating benign and malignant cervical lymph nodes, thereby informing decisions to perform a biopsy and facilitating follow-up. For US elastography to be accepted into clinical practice, however, its techniques, associated diagnostic criteria, and reliability need to be further refined.

  20. Usefulness of semiquantitative elastography in predicting malignancy in thyroid nodules.

    Science.gov (United States)

    Franco Uliaque, C; Pardo Berdún, F J; Laborda Herrero, R; Pérez Lórenz, C

    2016-01-01

    To retrospectively review the diagnostic capacity of semiquantitative elastography in differentiating between benign and malignant thyroid nodules. We analyzed 314 thyroid nodules in 295 consecutive patients referred to the endocrinology department for cytological study, studying all by conventional ultrasonography, elastography, and fine-needle aspiration cytology (FNAC). Using a semiquantitative elastography system that portrays tissue stiffness through a color map, we designed our own classification system for thyroid nodules based on their characteristics on elastography. We classified nodules into three groups: predominantly soft, predominantly stiff, and mosaic patterned. We used logistic regression analysis to investigate the relation between elastography and thyroid cancer. We obtained a definite diagnosis of malignancy after surgery in 19 nodules, of which on elastography 8 had the mosaic pattern, 6 were predominantly stiff, and 5 were predominantly soft. We found no significant association between the pattern on elastography and the probability of malignancy in any of the models. According to our study, la probability of malignancy in a thyroid nodule is not related to the findings at elastography. Therefore, semiquantitative elastography as used in this study cannot obviate FNAC. Copyright © 2016 SERAM. Publicado por Elsevier España, S.L.U. All rights reserved.

  1. Endorectal ultrasonography, strain elastography and MRI differentiation of rectal adenomas and adenocarcinomas

    DEFF Research Database (Denmark)

    Waage, Jo Erling Riise; Leh, Sabine; Røsler, Cornelia

    2015-01-01

    adenomas from adenocarcinomas. ERUS and MRI were performed according to standard routine at the institution, defining T0 as adenomas and T1-4 as adenocarcinomas. Subsequent histopathology was used as reference standard. RESULTS: Histopathological evaluation revealed 21 adenomas and 99 adenocarcinomas...... confirms that the elastography SR assessment accurately differentiates sessile adenomas from adenocarcinomas. SR assessment has a superior ability to differentiate adenomas and adenocarcinomas when compared with ERUS and MRI. MRI examination seems unable to recognize adenomas, and should be interpreted......AIM: Strain elastography is a method for recording tissue hardness. Strain in different areas may be compared using strain ratio (SR). The aims of this study were to validate a previously proposed SR cut-off value of 1.25 for differentiating adenocarcinomas from adenomas and to compare...

  2. Attenuation measuring ultrasound shearwave elastography and in vivo application in post-transplant liver patients

    Science.gov (United States)

    Nenadic, Ivan Z.; Qiang, Bo; Urban, Matthew W.; Zhao, Heng; Sanchez, William; Greenleaf, James F.; Chen, Shigao

    2017-01-01

    Ultrasound and magnetic resonance elastography techniques are used to assess mechanical properties of soft tissues. Tissue stiffness is related to various pathologies such as fibrosis, loss of compliance, and cancer. One way to perform elastography is measuring shear wave velocity of propagating waves in tissue induced by intrinsic motion or an external source of vibration, and relating the shear wave velocity to tissue elasticity. All tissues are inherently viscoelastic and ignoring viscosity biases the velocity-based estimates of elasticity and ignores a potentially important parameter of tissue health. We present attenuation measuring ultrasound shearwave elastography (AMUSE), a technique that independently measures both shear wave velocity and attenuation in tissue and therefore allows characterization of viscoelasticity without using a rheological model. The theoretical basis for AMUSE is first derived and validated in finite element simulations. AMUSE is validated against the traditional methods for assessing shear wave velocity (phase gradient) and attenuation (amplitude decay) in tissue mimicking phantoms and excised tissue. The results agreed within one standard deviation. AMUSE was used to measure shear wave velocity and attenuation in 15 transplanted livers in patients with potential acute rejection, and the results were compared with the biopsy findings in a preliminary study. The comparison showed excellent agreement and suggests that AMUSE can be used to separate transplanted livers with acute rejection from livers with no rejection.

  3. Attenuation measuring ultrasound shearwave elastography and in vivo application in post-transplant liver patients.

    Science.gov (United States)

    Nenadic, Ivan Z; Qiang, Bo; Urban, Matthew W; Zhao, Heng; Sanchez, William; Greenleaf, James F; Chen, Shigao

    2017-01-21

    Ultrasound and magnetic resonance elastography techniques are used to assess mechanical properties of soft tissues. Tissue stiffness is related to various pathologies such as fibrosis, loss of compliance, and cancer. One way to perform elastography is measuring shear wave velocity of propagating waves in tissue induced by intrinsic motion or an external source of vibration, and relating the shear wave velocity to tissue elasticity. All tissues are inherently viscoelastic and ignoring viscosity biases the velocity-based estimates of elasticity and ignores a potentially important parameter of tissue health. We present attenuation measuring ultrasound shearwave elastography (AMUSE), a technique that independently measures both shear wave velocity and attenuation in tissue and therefore allows characterization of viscoelasticity without using a rheological model. The theoretical basis for AMUSE is first derived and validated in finite element simulations. AMUSE is validated against the traditional methods for assessing shear wave velocity (phase gradient) and attenuation (amplitude decay) in tissue mimicking phantoms and excised tissue. The results agreed within one standard deviation. AMUSE was used to measure shear wave velocity and attenuation in 15 transplanted livers in patients with potential acute rejection, and the results were compared with the biopsy findings in a preliminary study. The comparison showed excellent agreement and suggests that AMUSE can be used to separate transplanted livers with acute rejection from livers with no rejection.

  4. [Elastography of cervix to predict delay from induction to delivery].

    Science.gov (United States)

    Sonnier, L; Bouhanna, P; Arnou, C; Rozenberg, P

    2014-12-01

    Induction of labor for medical indications has become a routine practice. To date, the Bishop score remains as the standard method to predict the duration of induced labor. Elastography is an objective method of assessing the relative consistency of tissues. Therefore, we sought to assess strain elastography of cervix to predict delay from induction to delivery in pregnant women with a low Bishop score. Ultrasound elastography was immediately performed before induction of labor for medical indications among patients with a singleton pregnancy at>36 weeks of gestation and a Bishop scorecolor map from blue (hardest tissue) to red (softest tissue) was produced. The cervical elastography was considered as positive if at least one part of its anterior wall was red. We assessed the predictive value of elastography on vaginal delivery within 24 hours. Patients delivering by cesarean section were excluded from this study. Elastography was initially performed in 48 patients. Twelve patients delivering by cesarean section after induction of labor were excluded, leading to 36 patients evaluated in this study. Among these 36 patients with elastography performed before induction of labor, 20 had a second elastography before the second dose of misoprostol. Sensibility, specificity, positive predictive value (PPV) and negative predictive value (NPV) of elastography performed before induction of labor on vaginal delivery within 24 hours were 40%, 27.3%, 55.6%, and 16.7%, respectively. Sensibility, specificity, PPV and NPV of elastography performed before the second dose of misoprostol were 64.3%, 16.7%, 64.3% and 16.7%, respectively. Among the 8 patients with red color occurring on the second cervical color map, sensibility, specificity, PPV and NPV were 83.3%, 0%, 62.5%, and 0%. Qualitative cervical elastography is a poor predictor for delay from induction to delivery in pregnant women with a low Bishop score. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  5. Sonographic Elastography of the Thyroid Gland

    OpenAIRE

    Menzilcioglu, Mehmet Sait; Duymus, Mahmut; Avcu, Serhat

    2016-01-01

    Summary Thyroid gland disorders include benign and malignant thyroid nodules and diffuse thyroid disorders. The incidence of malignant thyroid nodules is low and the prognosis is good. The diagnosis of thyroid cancer and diffuse parenchymal disorders is generally based on clinical manifestations and histopathological evaluation. Ultrasonography has its place in the diagnostics and follow-up of thyroid disorders. Ultrasonographic elastography is a new, developing method that shows increase in ...

  6. Real-Time Elastography of the Prostate

    OpenAIRE

    Junker, D; T. De Zordo; Quentin, M.; Ladurner, M; Bektic, J.; Horniger, W.; Jaschke, W.; Aigner, F.

    2014-01-01

    Palpation of organs is one of the oldest clinical examination techniques, for instance, if you think of the palpation of the breast or the digital rectal examination of the prostate, where hard palpable regions are suspicious for cancer. This is the basic principle of real-time elastography, an ultrasound technique, which is able to visualise tissue elasticity. Since prostate cancer features an increased stiffness due to the higher cell and vessel density than the normal surrounding tissue, r...

  7. Compressed Sensing for Elastography in Portable Ultrasound.

    Science.gov (United States)

    Shin, Bonghun; Jeon, Soo; Ryu, Jeongwon; Kwon, Hyock Ju

    2017-11-01

    Portable ultrasound is recently emerging as a new medical imaging modality featuring high portability, easy connectivity, and real-time on-site diagnostic ability. However, it does not yet provide ultrasound elastography function that enables the diagnosis of malignant lesions using elastic properties. This is mainly due to the limitations of hardware performance and wireless data transfer speed for processing the large amount of data for elastography. Therefore, data transfer reduction is one of the feasible solutions to overcome these limitations. Recently, compressive sensing (CS) theory has been rigorously studied as a means to break the conventional Nyquist sampling rate and thus can significantly decrease the amount of measurement signals without sacrificing signal quality. In this research, we implemented various CS reconstruction frameworks and comparatively evaluated their reconstruction performance for realizing ultrasound elastography function on portable ultrasound. Combinations of three most common model bases (Fourier transform [FT], discrete cosine transform [DCT], and wave atom [WA]) and two reconstruction algorithms (L1 minimization and block sparse Bayesian learning [BSBL]) were considered for CS frameworks. Echoic and elastography phantoms, were developed to evaluate the performance of CS on B-mode images and elastograms. To assess the reconstruction quality, mean absolute error (MAE), signal-to-noise ratio (SNRe), and contrast-to-noise ratio (CNRe) were measured on the B-mode images and elastograms from CS reconstructions. Results suggest that CS reconstruction adopting BSBL algorithm with DCT model basis can yield the best results for all the measures tested, and the maximum data reduction rate for producing readily discernable elastograms is around 60%.

  8. Management of rotator cuff calcific tendinosis guided by ultrasound elastography

    Directory of Open Access Journals (Sweden)

    Yen-Huai Lin

    2015-10-01

    Conclusion: Ultrasound elastography is a useful modality for evaluation of rotator cuff calcific tendinosis, and as an aid to guide management. If elastography shows the calcified area as a non-dark pattern, then fine-needle aspiration should be performed.

  9. Current status of musculoskeletal application of shear wave elastography

    Directory of Open Access Journals (Sweden)

    JeongAh Ryu

    2017-07-01

    Full Text Available Ultrasonography (US is a very powerful diagnostic modality for the musculoskeletal system due to the ability to perform real-time dynamic high-resolution examinations with the Doppler technique. In addition to acquiring morphologic data, we can now obtain biomechanical information by quantifying the elasticity of the musculoskeletal structures with US elastography. The earlier diagnosis of degeneration and the ability to perform follow-up evaluations of healing and the effects of treatment are possible. US elastography enables a transition from US-based inspection to US-based palpation in order to diagnose the characteristics of tissue. Shear wave elastography is considered the most suitable type of US elastography for the musculoskeletal system. It is widely used for tendons, ligaments, and muscles. It is important to understand practice guidelines in order to enhance reproducibility. Incorporating viscoelasticity and overcoming inconsistencies among manufacturers are future tasks for improving the capabilities of US elastography.

  10. Endoscopic Ultrasound Elastography: Current Clinical Use in Pancreas.

    Science.gov (United States)

    Mondal, Utpal; Henkes, Nichole; Patel, Sandeep; Rosenkranz, Laura

    2016-08-01

    Elastography is a newer technique for the assessment of tissue elasticity using ultrasound. Cancerous tissue is known to be stiffer (hence, less elastic) than corresponding healthy tissue, and as a result, could be identified in an elasticity-based imaging. Ultrasound elastography has been used in the breast, thyroid, and cervix to differentiate malignant from benign neoplasms and to guide or avoid unnecessary biopsies. In the liver, elastography has enabled a noninvasive and reliable estimate of fibrosis. Endoscopic ultrasound has become a robust diagnostic and therapeutic tool for the management of pancreatic diseases. The addition of elastography to endoscopic ultrasound enabled further characterization of pancreas lesions, and several European and Asian studies have reported encouraging results. The current clinical role of endoscopic ultrasound elastography in the management of pancreas disorders and related literature are reviewed.

  11. Current status of musculoskeletal application of shear wave elastography

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Jeong Ah [Dept. of Radiology, Hanyang University Guri Hospital, Hanyang University School of Medicine, Guri (Korea, Republic of); Jeong, Woo Kyoung [Dept. of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2017-07-15

    Ultrasonography (US) is a very powerful diagnostic modality for the musculoskeletal system due to the ability to perform real-time dynamic high-resolution examinations with the Doppler technique. In addition to acquiring morphologic data, we can now obtain biomechanical information by quantifying the elasticity of the musculoskeletal structures with US elastography. The earlier diagnosis of degeneration and the ability to perform follow-up evaluations of healing and the effects of treatment are possible. US elastography enables a transition from US-based inspection to US-based palpation in order to diagnose the characteristics of tissue. Shear wave elastography is considered the most suitable type of US elastography for the musculoskeletal system. It is widely used for tendons, ligaments, and muscles. It is important to understand practice guidelines in order to enhance reproducibility. Incorporating viscoelasticity and overcoming inconsistencies among manufacturers are future tasks for improving the capabilities of US elastography.

  12. Ultrasound Elastography for Estimation of Regional Strain of Multilayered Hydrogels and Tissue-Engineered Cartilage.

    Science.gov (United States)

    Chung, Chen-Yuan; Heebner, Joseph; Baskaran, Harihara; Welter, Jean F; Mansour, Joseph M

    2015-12-01

    Tissue-engineered (TE) cartilage constructs tend to develop inhomogeneously, thus, to predict the mechanical performance of the tissue, conventional biomechanical testing, which yields average material properties, is of limited value. Rather, techniques for evaluating regional and depth-dependent properties of TE cartilage, preferably non-destructively, are required. The purpose of this study was to build upon our previous results and to investigate the feasibility of using ultrasound elastography to non-destructively assess the depth-dependent biomechanical characteristics of TE cartilage while in a sterile bioreactor. As a proof-of-concept, and to standardize an assessment protocol, a well-characterized three-layered hydrogel construct was used as a surrogate for TE cartilage, and was studied under controlled incremental compressions. The strain field of the construct predicted by elastography was then validated by comparison with a poroelastic finite-element analysis (FEA). On average, the differences between the strains predicted by elastography and the FEA were within 10%. Subsequently engineered cartilage tissue was evaluated in the same test fixture. Results from these examinations showed internal regions where the local strain was 1-2 orders of magnitude greater than that near the surface. These studies document the feasibility of using ultrasound to evaluate the mechanical behaviors of maturing TE constructs in a sterile environment.

  13. Clinical quality indicators of venous leg ulcers

    DEFF Research Database (Denmark)

    Kjaer, Monica L; Mainz, Jan; Soernsen, Lars T

    2005-01-01

    In the clinical setting, diagnosis and treatment of venous leg ulcers can vary considerably from patient to patient. The first step to reducing this variation is to document venous leg ulcer care through use of quantitative scientific documentation principles. This requires the development of valid...... and reliable evidence-based quality indicators of venous leg ulcer care. A Scandinavian multidisciplinary, cross-sectional panel of wound healing experts developed clinical quality indicators on the basis of scientific evidence from the literature and subsequent group nominal consensus of the panel......; an independent medical doctor tested the feasibility and reliability of these clinical indicators, assessing the quality of medical technical care on 100 consecutive venous leg ulcer patients. Main outcome measures were healing, recurrence, pain, venous disease diagnosis, differential diagnosis and treatment...

  14. Central venous catheter - flushing

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000157.htm Central venous catheter - flushing To use the sharing features on this page, please enable JavaScript. You have a central venous catheter. This is a tube that goes into a ...

  15. Endobronchial Ultrasound Elastography for Diagnosing Mediastinal and Hilar Lymph Nodes

    Directory of Open Access Journals (Sweden)

    Hai-Yan He

    2015-01-01

    Full Text Available Background: Pathophysiological processes, such as malignancy, can lead to the formation of stiffer tissue in lung cancers. Endobronchial ultrasound (EBUS elastography is a novel technique for measuring tissue stiffness during EBUS-guided transbronchial needle aspiration (EBUS-TBNA. The current study was conducted to investigate the diagnostic value of EBUS elastography for mediastinal and hilar lymph node metastasis in lung cancers. Methods: From January 2014 to January 2015, 40 patients suspected of lung cancer were enrolled, and a total of 68 lymph nodes were evaluated by EBUS-TBNA. EBUS-guided elastography of lymph nodes was performed prior to EBUS-TBNA. Standard EBUS characteristics were also described. Pathological determination of malignant or benign lymph nodes was used as the gold standard for this study. If EBUS-TBNA did not result in a formal pathological diagnosis of malignancy, patients were referred for a surgical procedure. Comparisons of elastography and standard EBUS characteristics were made between benign and malignant lymph nodes. Results: Elastography grading scores and strain ratios showed significant differences between benign and malignant lymph nodes (P = 0.000. The elastography strain ratio was more sensitive and specific for determining malignant lymph nodes than elastography grading score or standard EBUS criteria. The receiver operating characteristic curve for the elastography strain ratio showed an area under the curve of 0.933. The best cut-off point of the strain ratio for differentiating malignant from benign lymph nodes was 32.07. The elastography strain ratio had a sensitivity of 88.1%, the specificity of 80.8%, positive predictive value of 88.1%, and negative predictive value of 80.8% for distinguishing malignant from benign nodes. The overall accuracy of elastography strain ratio was 85.3%. The strain ratio of malignant and benign lymph nodes positively correlated with the elastography grading score (r = 0

  16. Ultrasound elastography in the early diagnosis of plantar fasciitis.

    Science.gov (United States)

    Lee, So-Yeon; Park, Hee Jin; Kwag, Hyon Joo; Hong, Hyun-Pyo; Park, Hae-Won; Lee, Yong-Rae; Yoon, Kyung Jae; Lee, Yong-Taek

    2014-01-01

    The purpose of this study was to investigate whether ultrasound (US) elastography is useful for the early diagnosis of plantar fasciitis. We retrospectively reviewed US elastography findings of 18 feet with a clinical history and physical examination highly suggestive of plantar fasciitis but with normal findings on conventional US imaging as well as 18 asymptomatic feet. Softening of the plantar fascia was significantly greater in the patient than in the control group [Reviewers 1 and 2: 89% (16/18) vs. 50% (9/18), P=.027, respectively]. US elastography is useful for the early diagnosis of plantar fasciitis. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Contemporary use of elastography in liver fibrosis and portal hypertension

    DEFF Research Database (Denmark)

    Thiele, Maja; Kjærgaard, Maria; Thielsen, Peter

    2017-01-01

    The risk and speed of progression from fibrosis to compensated and decompensated cirrhosis define the prognosis in liver diseases. Therefore, early detection and preventive strategies affect outcomes. Patients with liver disease have traditionally been diagnosed at an advanced stage of disease......, in part due to lack of non-invasive markers. Ultrasound elastography to measure liver stiffness can potentially change this paradigm. The purpose of this review was therefore to summarize advances in the field of ultrasound elastography with focus on diagnosis of liver fibrosis, cirrhosis and clinically...... significant portal hypertension, techniques and limitations. Four types of ultrasound elastography exist, but there is scarce evidence comparing the different techniques. The majority of experience concern transient elastography for diagnosing fibrosis and cirrhosis in patients with chronic viral hepatitis C...

  18. Nodular thyroid cancer. Diagnostic value of real time elastography

    National Research Council Canada - National Science Library

    Stoian, D; Cornianuz, M; Dobrescu, A; Lazăr, F

    2012-01-01

    The most important aspect in the diagnostic approach of thyroid nodule is identifying the malignancy Elastography is a newly technique that measures the elasticity of tissue, after applying a external...

  19. Strain Elastography of Breast and Prostata Cancer: Similarities and Differences.

    Science.gov (United States)

    Daniaux, M; Auer, T; De Zordo, T; Junker, D; Santner, W; Hubalek, M; Jaschke, W; Aigner, F

    2016-03-01

    Typically both breast and prostate cancer present as tissue with decreased elasticity. Palpation is the oldest technique of tumor detection in both organs and is based on this principle. Thus an operator can grade a palpable mass as suspicious for cancer. Strain elastography as modern ultrasound technique allows the visualization of tissue elasticity in a color coded elastogram and can be understood as technical finger. The following article shows similarities and differences of ultrasound strain elastography in the diagnosis of breast and prostate cancer. • In prostata cancer elastography, in breast cancer B-mode is the primary sonographic search modality. • The diagnostic value of the search modalities change with increasing age.• A cut-off value for a strain ratio is hard to obtain in the elastography of the prostata, because there is no stabile reference tissue in the prostata. © Georg Thieme Verlag KG Stuttgart · New York.

  20. Predicting target displacements using ultrasound elastography and finite element modeling

    NARCIS (Netherlands)

    Buijs, J.O. den; Hansen, H.H.G.; Lopata, R.G.P.; Korte, C.L. de; Misra, S.

    2011-01-01

    Soft tissue displacements during minimally invasive surgical procedures may cause target motion and subsequent misplacement of the surgical tool. A technique is presented to predict target displacements using a combination of ultrasound elastography and finite element (FE) modeling. A cubic

  1. Predicting target displacements using ultrasound elastography and finite element modeling

    NARCIS (Netherlands)

    op den Buijs, J.; Hansen, Hendrik H.G.; Lopata, Richard G.P.; de Korte, Chris L.; Misra, Sarthak

    Soft tissue displacements during minimally invasive surgical procedures may cause target motion and subsequent misplacement of the surgical tool. A technique is presented to predict target displacements using a combination of ultrasound elastography and finite element (FE) modeling. A cubic

  2. Elastography of the Breast: Imaging Techniques and Pitfalls in Interpretation

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Woo Kyung; Chang, Jung Min; Cho, Nariya [Seoul National University Hospital, Seoul (Korea, Republic of)

    2011-12-15

    Ultrasound (US) elastography is a tool that indicates the hardness of a lesion. Recent studies using elastography with freehand compression have shown similar diagnostic performance to conventional US in differentiating benign lesions from malignant breast masses. On the other hand, the acquired information is not quantitative, and the reliability of the imaging technique to correctly compress the tissue depends on the skill of the operator, resulting in substantial interobserver variability during data acquisition and interpretation. To overcome this, shear wave elastography was developed to provide quantitative information on the tissue elasticity. The system works by remotely inducing mechanical vibrations through the acoustic radiation force created by a focused US beam. This review discusses the principles and examination techniques of the two types of elastography systems and provides practical points to reduce the interobserver variability or errors during data acquisition and interpretation

  3. Differential diagnosis of breast lesions using ultrasound elastography

    Directory of Open Access Journals (Sweden)

    Ioana Andreea Gheonea

    2011-01-01

    Full Text Available Context: The recent introduction of elastography has increased the specificity of USG and enabled early diagnosis of breast cancer. Quantitative elastography, especially with strain ratio (SR index, improves diagnostic accuracy and decreased number of biopsies. Aims: The purpose of this study was to assess the role of USG elastography in the differential diagnosis of breast lesions. Settings and Design: This prospective study was conducted in the University of Medicine and Pharmacy Research Centre of Craiova. Materials and Methods: Fifty-eight patients diagnosed with breast lesions between January 2009 and January 2010 were included in this prospective study. All the patients were examined in the supine position, and the B-mode USG image was displayed alongside the elastography strain image. For obtaining the elastography images we used a EUS Hitachi EUB 8500 ultrasound system with a 6.5-MHz linear probe. The elastography strain images were scored according to the Tsukuba elasticity score. Statistical Analysis: We performed receiver operator characteristic (ROC analysis for assessment of the role of USG elastography in the diagnosis of breast lesions. Results: We obtained a sensitivity of 86.7% and a specificity of 92.9% for elasticity score and a sensitivity of 93.3% and a specificity of 92.9% for SR (when a cutoff point of 3.67 was used. There was very good correlation between SR and elasticity score (Spearman coefficient of 0.911. Conclusions: Elastography is a fast, simple method that can complement conventional USG examination. This method has the lowest cost/efficiency ratio and it is also the most noninvasive and accessible imaging method, with an accuracy comparable to MRI.

  4. Clinical validation of semi-automated software for volumetric and dynamic contrast enhancement analysis of soft tissue venous malformations on magnetic resonance imaging examination

    Energy Technology Data Exchange (ETDEWEB)

    Caty, Veronique [Hopital Maisonneuve-Rosemont, Universite de Montreal, Department of Radiology, Montreal, QC (Canada); Kauffmann, Claude; Giroux, Marie-France; Oliva, Vincent; Therasse, Eric [Centre Hospitalier de l' Universite de Montreal (CHUM), Universite de Montreal and Research Centre, CHUM (CRCHUM), Department of Radiology, Montreal, QC (Canada); Dubois, Josee [Centre Hospitalier Universitaire Sainte-Justine et Universite de Montreal, Department of Radiology, Montreal, QC (Canada); Mansour, Asmaa [Institut de Cardiologie de Montreal, Heart Institute Coordinating Centre, Montreal, QC (Canada); Piche, Nicolas [Object Research System, Montreal, QC (Canada); Soulez, Gilles [Centre Hospitalier de l' Universite de Montreal (CHUM), Universite de Montreal and Research Centre, CHUM (CRCHUM), Department of Radiology, Montreal, QC (Canada); CHUM - Hopital Notre-Dame, Department of Radiology, Montreal, Quebec (Canada)

    2014-02-15

    To evaluate venous malformation (VM) volume and contrast-enhancement analysis on magnetic resonance imaging (MRI) compared with diameter evaluation. Baseline MRI was undertaken in 44 patients, 20 of whom were followed by MRI after sclerotherapy. All patients underwent short-tau inversion recovery (STIR) acquisitions and dynamic contrast assessment. VM diameters in three orthogonal directions were measured to obtain the largest and mean diameters. Volumetric reconstruction of VM was generated from two orthogonal STIR sequences and fused with acquisitions after contrast medium injection. Reproducibility (interclass correlation coefficients [ICCs]) of diameter and volume measurements was estimated. VM size variations in diameter and volume after sclerotherapy and contrast enhancement before sclerotherapy were compared in patients with clinical success or failure. Inter-observer ICCs were similar for diameter and volume measurements at baseline and follow-up (range 0.87-0.99). Higher percentages of size reduction after sclerotherapy were observed with volume (32.6 ± 30.7 %) than with diameter measurements (14.4 ± 21.4 %; P = 0.037). Contrast enhancement values were estimated at 65.3 ± 27.5 % and 84 ± 13 % in patients with clinical failure and success respectively (P = 0.056). Venous malformation volume was as reproducible as diameter measurement and more sensitive in detecting therapeutic responses. Patients with better clinical outcome tend to have stronger malformation enhancement. (orig.)

  5. Acoustic Radiation Force Impulse Elastography for fibrosis evaluation in patients with chronic hepatitis C: An international multicenter study

    Energy Technology Data Exchange (ETDEWEB)

    Sporea, Ioan, E-mail: isporea@umft.ro [Department of Gastroenterology and Hepatology, University of Medicine and Pharmacy Timisoara (Romania); Bota, Simona, E-mail: bota_simona1982@yahoo.com [Department of Gastroenterology and Hepatology, University of Medicine and Pharmacy Timisoara (Romania); Peck-Radosavljevic, Markus, E-mail: markus.peck@meduniwien.ac.at [Internal Medicine III, Division of Gastroenterology and Hepatology, Medical University of Vienna (Austria); Sirli, Roxana, E-mail: roxanasirli@gmail.com [Department of Gastroenterology and Hepatology, University of Medicine and Pharmacy Timisoara (Romania); Tanaka, Hironori, E-mail: hironori@hyo-med.ac.jp [Department of Internal Medicine, Hyogo College of Medicine, Nishinomiya (Japan); Iijima, Hiroko, E-mail: hiroko.iijima@nifty.com [Department of Internal Medicine, Hyogo College of Medicine, Nishinomiya (Japan); Badea, Radu, E-mail: rbadea2003@yahoo.com [3rd Medical Clinic, University of Medicine, Cluj Napoca (Romania); Lupsor, Monica, E-mail: monica.lupsor@umfcluj.ro [3rd Medical Clinic, University of Medicine, Cluj Napoca (Romania); Fierbinteanu-Braticevici, Carmen, E-mail: cfierbinteanu@yahoo.com [2nd Medical Clinic and Gastroenterology, University Hospital, Bucharest (Romania); Petrisor, Ana, E-mail: ana1petrisor@yahoo.com [2nd Medical Clinic and Gastroenterology, University Hospital, Bucharest (Romania); Saito, Hidetsugu, E-mail: hidetsugusaito@gmail.com [Department of Internal Medicine, School of Medicine, Keio University, Tokyo (Japan); Ebinuma, Hirotoshi, E-mail: ebinuma@a5.keio.jp [Department of Internal Medicine, School of Medicine, Keio University, Tokyo (Japan); Friedrich-Rust, Mireen, E-mail: Mireen.Friedrich-Rust@kgu.de [Department of Internal Medicine, J.W. Goethe University, Frankfurt/Main (Germany); Sarrazin, Christoph, E-mail: sarrazin@em.uni-frankfurt.de [Department of Internal Medicine, J.W. Goethe University, Frankfurt/Main (Germany); and others

    2012-12-15

    Aim: The aim of this international multicenter study was to evaluate the reliability of Acoustic Radiation Force Impulse (ARFI) elastography for predicting fibrosis severity, in patients with chronic hepatitis C. Patients and methods: We compared ARFI to liver biopsy (LB) in 914 patients (10 centers, 5 countries) with chronic hepatitis C. In each patient LB (evaluated according to the METAVIR score) and ARFI measurements were performed (median of 5–10 valid measurements, expressed in meters/second – m/s). In 400 from the 914 patients, transient elastography (TE) was also performed (median of 6–10 valid measurements, expressed in kiloPascals – kPa). Results: Valid ARFI measurements were obtained in 911 (99.6%) of 914 cases. On LB 61 cases (6.7%) had F0, 241 (26.4%) had F1, 202 (22.1%) had F2, 187 (20.4%) had F3, and 223 (24.4%) had F4 fibrosis. A highly significant correlation (r = 0.654) was found between ARFI measurements and fibrosis (p < 0.0001). The predictive values of ARFI for various stages of fibrosis were: F ≥ 1 – cut-off > 1.19 m/s (AUROC = 0.779), F ≥ 2 – cut-off > 1.33 m/s (AUROC = 0.792), F ≥ 3 – cut-off > 1.43 m/s (AUROC = 0.829), F = 4 – cut-off > 1.55 m/s (AUROC = 0.842). The correlation with histological fibrosis was not significantly different for TE in comparison with ARFI elastography: r = 0.728 vs. 0.689, p = 0.28. TE was better than ARFI for predicting the presence of liver cirrhosis (p = 0.01) and fibrosis (F ≥ 1, METAVIR) (p = 0.01). Conclusion: ARFI elastography is a reliable method for predicting fibrosis severity in chronic hepatitis C patients.

  6. Management of rotator cuff calcific tendinosis guided by ultrasound elastography.

    Science.gov (United States)

    Lin, Yen-Huai; Chiou, Hong-Jen; Wang, Hsin-Kai; Lai, Yi-Chen; Chou, Yi-Hong; Chang, Cheng-Yen

    2015-10-01

    Ultrasound (US) elastography can provide information about the hardness of calcification and might help decide treatment strategy. The purpose of this study was to evaluate the hardness of the calcific area within rotator cuffs by US elastography as an aid for the selection of aspiration or fine-needle repeated puncture for the treatment of rotator cuff calcific tendinosis. This prospective study included 39 patients (32 males, 7 females; mean age, 52.9 years) who received US elastography and gray-scale ultrasonography before US-guided treatment for rotator cuff calcific tendinosis. The morphology of the calcifications was classified as arc, fragmented, nodular, and cystic types. US elastography using virtual touch imaging (acoustic radiation force impulse) technique was performed to examine the calcified region to obtain an elastogram that was graded dark, intermediate, or bright. The hardness of the calcifications were recorded, and graded as hard, sand-like, or fluid-like tactile patterns during the US-guided treatment, and the tactile patterns were compared with the results of US elastography and gray-scale ultrasonography. Though the morphologies of the calcifications were significantly related to the tactile pattern of the needle punctures (p tendinosis, and as an aid to guide management. If elastography shows the calcified area as a non-dark pattern, then fine-needle aspiration should be performed. Copyright © 2015. Published by Elsevier Taiwan.

  7. Shear wave elastography with a new reliability indicator

    Directory of Open Access Journals (Sweden)

    Christoph F. Dietrich

    2016-09-01

    Full Text Available Non-invasive methods for liver stiffness assessment have been introduced over recent years. Of these, two main methods for estimating liver fibrosis using ultrasound elastography have become established in clinical practice: shear wave elastography and quasi-static or strain elastography. Shear waves are waves with a motion perpendicular (lateral to the direction of the generating force. Shear waves travel relatively slowly (between 1 and 10 m/s. The stiffness of the liver tissue can be assessed based on shear wave velocity (the stiffness increases with the speed. The European Federation of Societies for Ultrasound in Medicine and Biology has published Guidelines and Recommendations that describe these technologies and provide recommendations for their clinical use. Most of the data available to date has been published using the Fibroscan (Echosens, France, point shear wave speed measurement using an acoustic radiation force impulse (Siemens, Germany and 2D shear wave elastography using the Aixplorer (SuperSonic Imagine, France. More recently, also other manufacturers have introduced shear wave elastography technology into the market. A comparison of data obtained using different techniques for shear wave propagation and velocity measurement is of key interest for future studies, recommendations and guidelines. Here, we present a recently introduced shear wave elastography technology from Hitachi and discuss its reproducibility and comparability to the already established technologies.

  8. An analytical poroelastic model for ultrasound elastography imaging of tumors

    Science.gov (United States)

    Tauhidul Islam, Md; Chaudhry, Anuj; Unnikrishnan, Ginu; Reddy, J. N.; Righetti, Raffaella

    2018-01-01

    The mechanical behavior of biological tissues has been studied using a number of mechanical models. Due to the relatively high fluid content and mobility, many biological tissues have been modeled as poroelastic materials. Diseases such as cancers are known to alter the poroelastic response of a tissue. Tissue poroelastic properties such as compressibility, interstitial permeability and fluid pressure also play a key role for the assessment of cancer treatments and for improved therapies. At the present time, however, a limited number of poroelastic models for soft tissues are retrievable in the literature, and the ones available are not directly applicable to tumors as they typically refer to uniform tissues. In this paper, we report the analytical poroelastic model for a non-uniform tissue under stress relaxation. Displacement, strain and fluid pressure fields in a cylindrical poroelastic sample containing a cylindrical inclusion during stress relaxation are computed. Finite element simulations are then used to validate the proposed theoretical model. Statistical analysis demonstrates that the proposed analytical model matches the finite element results with less than 0.5% error. The availability of the analytical model and solutions presented in this paper may be useful to estimate diagnostically relevant poroelastic parameters such as interstitial permeability and fluid pressure, and, in general, for a better interpretation of clinically-relevant ultrasound elastography results.

  9. Cerebral venous angiomas

    Energy Technology Data Exchange (ETDEWEB)

    Agnoli, A.L.; Hildebrandt, G.

    1985-01-01

    Clinical symptoms and radiological signs in 15 patients with cerebral venous malformations are presented and the diagnostic problems discussed. The circulation time in combination with cerebral malformations and angiomas of the scalp are described. CT findings in cases of venous malformations of the brain stem are evaluated. Spot-like enhancement, as well as sharply demarcated round shaped enhancement are characteristic for venous angiomas. Cavernous angiomas usually present as homogenous or inhomogenous round shaped enhanced areas. (Author).

  10. Persistent portal venous gas.

    Science.gov (United States)

    Huurman, Volkert A L; Visser, Leo G; Steens, Stefan C A; Terpstra, Onno T; Schaapherder, Alexander F M

    2006-05-01

    This case report describes a patient diagnosed with ongoing portal venous gas, initiated by a rather common Campylobacter enterocolitis and maintained by septic thrombophlebitis and possibly by chronic cholecystitis. Cholecystectomy attenuated the patient's septic condition. The etiology of portal venous gas determines both the patient's prognosis and the choice for either conservative or surgical treatment. This report describes persistence of portal venous gas for a long period and a possible role for chronic cholecystitis as a cause.

  11. Lifestyle and venous thrombosis

    NARCIS (Netherlands)

    Pomp, Elisabeth Rebekka

    2008-01-01

    In the Multiple Environmental and Genetic Assessment of risk factors for venous thrombosis (MEGA study), a large population-based case-control study, we investigated lifestyle factors as risk factors for venous thrombosis. Overweight, smoking and alcohol consumption were addressed and pregnancy and

  12. Shear-wave elastography of the breast: value of a quality measure and comparison with strain elastography.

    Science.gov (United States)

    Barr, Richard G; Zhang, Zheng

    2015-04-01

    To determine whether addition of quality measure (QM) of shear-wave (SW) velocity (Vs) estimation can increase SW elastography sensitivity for breast cancer. With written informed consent, this institutional review board-approved, HIPAA-compliant study included 143 women (mean age, 48.5 years ± 8.7) scheduled for breast biopsy. Mean lesion size was 16.4 mm ± 11.8; 95 (66%) lesions were benign; 48 (34%), malignant. If more than one lesion was present, lesion with highest Breast Imaging Reporting and Data System (BI-RADS) category was chosen. If there were more than one with highest BI-RADS category, a lesion was randomly selected. Conventional ultrasonography (US), strain elastography, and SW elastography were performed with QM. QM assesses SW quality to provide accurate Vs. Lesions were evaluated for Vs and QM (high or low). Lesions with Vs of less than 4.5 m/sec were classified benign; lesions with Vs of 4.5 m/sec or greater, malignant. Results were correlated with pathologic findings. Vs data with or without incorporating QM were used to determine SW elastography diagnostic performance. Binomial proportions and exact 95% confidence intervals (CIs) were calculated. In 95 benign lesions, 13 (14%) had no SW elastography signal; 77 (81%), Vs of less than 4.5 m/sec; and five (5%), Vs of 4.5 m/sec or greater. In 48 malignant lesions, eight (17%) had no SW elastography signal; 20 (42%), Vs of less than 4.5 m/sec; and 20 (42%), V of 4.5 m/sec or greater. QM was low in 17 of 20 (85%) malignant lesions with Vs of less than 4.5 m/sec. Without QM, using Vs of 4.5 m/sec or greater as test positive, SW elastography had lesion-level sensitivity of 50% (95% CI: 34%, 66%); specificity, 94% (95% CI: 86%, 98%); positive predictive value (PPV), 80% (95% CI: 59%, 93%); and negative predictive value (NPV), 79% (95% CI: 70%, 87%). Using QM where additional lesions with both low Vs and low QM were treated as test positive, SW elastography had lesion-level sensitivity of 93% (95% CI

  13. What we need to know when performing and interpreting US elastography

    Directory of Open Access Journals (Sweden)

    So Hyun Park

    2016-09-01

    Full Text Available According to the increasing need for accurate staging of hepatic fibrosis, the ultrasound (US elastography techniques have evolved significantly over the past two decades. Currently, US elastography is increasingly used in clinical practice. Previously published studies have demonstrated the excellent diagnostic performance of US elastography for the detection and staging of liver fibrosis. Although US elastography may seem easy to perform and interpret, there are many technical and clinical factors which can affect the results of US elastography. Therefore, clinicians who are involved with US elastography should be aware of these factors. The purpose of this article is to present a brief overview of US techniques with the relevant technology, the clinical indications, diagnostic performance, and technical and biological factors which should be considered in order to avoid misinterpretation of US elastography results.

  14. Chart validation of inpatient International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) administrative diagnosis codes for venous thromboembolism (VTE) among intravenous immune globulin (IGIV) users in the Sentinel Distributed Database.

    Science.gov (United States)

    Ammann, Eric M; Cuker, Adam; Carnahan, Ryan M; Perepu, Usha S; Winiecki, Scott K; Schweizer, Marin L; Leonard, Charles E; Fuller, Candace C; Garcia, Crystal; Haskins, Cole; Chrischilles, Elizabeth A

    2018-02-01

    The Sentinel Distributed Database (SDD) is a database of patient administrative healthcare records, derived from insurance claims and electronic health records, sponsored by the US Food and Drug Administration for evaluation of medical product outcomes. There is limited information on the validity of diagnosis codes for acute venous thromboembolism (VTE) in the SDD and administrative healthcare data more generally.In this chart validation study, we report on the positive predictive value (PPV) of inpatient administrative diagnosis codes for acute VTE-pulmonary embolism (PE) or lower-extremity or site-unspecified deep vein thrombosis (DVT)-within the SDD. As part of an assessment of thromboembolic adverse event risk following treatment with intravenous immune globulin (IGIV), charts were obtained for 75 potential VTE cases, abstracted, and physician-adjudicated.VTE status was determined for 62 potential cases. PPVs for lower-extremity DVT and/or PE were 90% (95% CI: 73-98%) for principal-position diagnoses, 80% (95% CI: 28-99%) for secondary diagnoses, and 26% (95% CI: 11-46%) for position-unspecified diagnoses (originating from physician claims associated with an inpatient stay). Average symptom onset was 1.5 days prior to hospital admission (range: 19 days prior to 4 days after admission).PPVs for principal and secondary VTE discharge diagnoses were similar to prior study estimates. Position-unspecified diagnoses were less likely to represent true acute VTE cases.

  15. Chlorhexidine and silver sulfadiazine coating on central venous catheters is not sufficient for protection against catheter-related infection: Simulation-based laboratory research with clinical validation

    Science.gov (United States)

    Choi, Yoon Ji; Lim, Jae Kwan; Park, Jeong Jun; Huh, Hyub; Kim, Dong-Joo; Gong, Chang-Hoon

    2017-01-01

    Objective The efficacy of chlorhexidine- and silver sulfadiazine-coated central venous catheters (CSS-CVC) against catheter-related infection remains controversial. We hypothesized that the loss of silver nanoparticles may reduce the antibacterial efficacy of CSS-CVCs and that this loss could be due to the frictional force between the surface of the CVC and the bloodstream. The objective of this study was to investigate whether the antimicrobial effect of CSS-CVCs decreases with increasing exposure time in a bloodstream model and quantitatively assay the antimicrobial effect of CSS-CVCs compared with polyurethane and antiseptic-impregnated CVCs. Methods Each CVC was subjected to 120 hours of saline flow and analyzed at intervals over 24 hours. The analyses included energy-dispersive X-ray spectroscopy, scanning electron microscopy, and optical density after a Staphylococcus aureus incubation test. Results The weight percentage of silver in the CSS-CVCs significantly decreased to 56.18% (44.10% ± 3.32%) with 48-hour catheterization and to 18.88% (14.82% ± 1.33%) with 120-hour catheterization compared with the initial weight percentage (78.50% ± 6.32%). In the S. aureus incubation test, the antibacterial function of CSS-CVCs was lost after 48 hours [3 (N/D) of OD]. Similar results were observed in a pilot clinical study using 18 CSS-CVCs. Conclusions We found that the efficacy of CSS-CVCs decreased over time and that the antibacterial function was lost after 48 hours of simulated wear-out. Therefore, antibiotic-impregnated CVCs may be a better option when longer (>48 hours) indwelling is needed. PMID:28534703

  16. EUS Elastography: Advances in Diagnostic EUS of the Pancreas

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Tae Hee; Cha, Sang Woo; Cho, Young Deok [Soonchunhyang University College of Medicine, Seoul (Korea, Republic of)

    2012-02-15

    Elastography is an imaging modality for the evaluation of tissue stiffness, which has been used for the analysis of superficial organs, such as those of the breast and prostate. The measurement of tissue elasticity has been reported to be useful for the diagnosis and differentiation of tumors, which are stiffer than normal tissues. Endoscopic ultrasonography elastography (EUS-EG) is a promising imaging technique with a high degree of accuracy for the differential diagnosis of solid pancreatic tumors. Recent introduction of second generation EUS-EG allows for the quantitative analysis of tissue stiffness. Here, we review our knowledge and preliminary experience with the use of EUS-elastography for the diagnosis of pancreatic disease.

  17. Hemoglobin measured by Hemocue and a reference method in venous and capillary blood: a validation study Hemoglobina medida por Hemocue y por un método de referencia en sangre venosa y capilar: estudio de validación

    OpenAIRE

    Lynnette Neufeld; Armando García-Guerra; Domingo Sánchez-Francia; Oscar Newton-Sánchez; María Dolores Ramírez-Villalobos; Juan Rivera-Dommarco

    2002-01-01

    Objective. To assess the comparability of hemoglobin concentration (Hb) in venous and capillary blood measured by Hemocue and an automated spectrophotometer (Celldyn) and to document the influence of type of blood (capillary or venous) and analysis method on anemia prevalence estimates. Material and Methods. Between February and May 2000, capillary and venous samples were collected from 72 adults and children at Hospital del Niño Morelense (Morelos State Children's Hospital) in Cuernavaca, Mo...

  18. Contrast-Enhanced Quantitative Intravascular Elastography: The Impact of Microvasculature on Model-Based Elastography.

    Science.gov (United States)

    Huntzicker, Steven; Shekhar, Himanshu; Doyley, Marvin M

    2016-05-01

    Model-based intravascular ultrasound elastography visualizes the stress distribution within vascular tissue-information that clinicians could use to predict the propensity of atherosclerotic plaque rupture. However, there are concerns that clusters of microvessels may reduce the accuracy of the estimated stress distribution. Consequently, we have developed a contrast-enhanced intravascular ultrasound system to investigate how plaque microvasculature affects the performance of model-based elastography. In simulations, diameters of 200, 400 and 800 μm were used, where the latter diameter represented a cluster of microvessels. In phantoms, we used a microvessel with a diameter of 750 μm. Peak stress errors of 3% and 38% were incurred in the fibrous cap when stress recovery was performed with and without a priori information about microvessel geometry. The results indicate that incorporating geometric information about plaque microvasculature obtained with contrast-enhanced ultrasound imaging improves the accuracy of estimates of the stress distribution within the fibrous cap precisely. Copyright © 2016 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  19. Can acoustic radiation force impulse elastography be a substitute for liver biopsy in predicting liver fibrosis?

    Science.gov (United States)

    Jain, V; Dixit, R; Chowdhury, V; Puri, A S; Gondal, R

    2016-09-01

    To evaluate the clinical feasibility and accuracy of acoustic radiation force impulse (ARFI) elastography for the detection of liver fibrosis in patients with chronic viral hepatitis. ARFI-based ultrasound elastography was performed in 69 patients with chronic liver disease (CLD) of viral aetiology and 36 healthy volunteers. Fifty-eight patients with CLD also underwent liver biopsy. ARFI was feasible in all 36 healthy volunteers and all 69 CLD patients, while valid measurements were obtained in 65 patients (95.6%) and all healthy volunteers. The mean shear-wave velocity (SWV) in healthy volunteers was 1.12±0.2 m/s. A gradual increase in mean SWV was noted from fibrosis of Grade F0 to F6 (Ishak's score) and a high positive correlation was found between the mean SWV on ARFI and fibrosis scores at liver biopsy (rho=0.789). The difference between the mild (F1 and F2) versus significant fibrosis (F3 and F4) was also statistically significant (pliver stiffness and may help to distinguish between no/mild fibrosis and significant fibrosis and guide management decisions. Copyright © 2016 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  20. Noncontact phase-sensitive dynamic optical coherence elastography at megahertz rate

    Science.gov (United States)

    Singh, Manmohan; Wu, Chen; Liu, Chih-Hao; Li, Jiasong; Schill, Alexander; Nair, Achuth; Kistenev, Yury V.; Larin, Kirill V.

    2016-03-01

    Dynamic optical coherence elastography (OCE) techniques have shown great promise at quantitatively obtaining the biomechanical properties of tissue. However, the majority of these techniques have required multiple temporal OCT acquisitions (M-B mode) and corresponding excitations, which lead to clinically unfeasible acquisition times and potential tissue damage. Furthermore, the large data sets and extended laser exposures hinder their translation to the clinic, where patient discomfort and safety are critical criteria. In this work we demonstrate noncontact true kilohertz frame-rate dynamic optical coherence elastography by directly imaging a focused air-pulse induced elastic wave with a home-built phase-sensitive OCE system based on a 4X buffered Fourier Domain Mode Locked swept source laser with an A-scan rate of ~1.5 MHz. The elastic wave was imaged at a frame rate of ~7.3 kHz using only a single excitation. In contrast to previous techniques, successive B-scans were acquired over the measurement region (B-M mode) in this work. The feasibility of this method was validated by quantifying the elasticity of tissue-mimicking agar phantoms as well as porcine corneas ex vivo at different intraocular pressures. The results demonstrate that this method can acquire a depth-resolved elastogram in milliseconds. The reduced data set enabled a rapid elasticity assessment, and the ultra-fast acquisition speed allowed for a clinically safe laser exposure to the cornea.

  1. Forward and inverse viscoelastic wave scattering by irregular inclusions for shear wave elastography.

    Science.gov (United States)

    Bernard, Simon; Cloutier, Guy

    2017-10-01

    Inversion methods in shear wave elastography use simplifying assumptions to recover the mechanical properties of soft tissues. Consequently, these methods suffer from artifacts when applied to media containing strong stiffness contrasts, and do not provide a map of the viscosity. In this work, the shear wave field recorded inside and around an inclusion was used to estimate the viscoelastic properties of the inclusion and surrounding medium, based on an inverse problem approach assuming local homogeneity of both media. An efficient semi-analytical method was developed to model the scattering of an elastic wave by an irregular inclusion, based on a decomposition of the field by Bessel functions and on a decomposition of the boundaries as Fourier series. This model was validated against finite element modeling. Shear waves were experimentally induced by acoustic radiation force in soft tissue phantoms containing stiff and soft inclusions, and the displacement field was imaged at a high frame rate using plane wave imaging. A nonlinear least-squares algorithm compared the model to the experimental data and adjusted the geometrical and mechanical parameters. The estimated shear storage and loss moduli were in good agreement with reference measurements, as well as the estimated inclusion shape. This approach provides an accurate estimation of geometry and viscoelastic properties for a single inclusion in a homogeneous background in the context of radiation force elastography.

  2. Calf venous compliance measured by venous occlusion plethysmography: methodological aspects.

    Science.gov (United States)

    Skoog, Johan; Zachrisson, Helene; Lindenberger, Marcus; Ekman, Mikael; Ewerman, Lea; Länne, Toste

    2015-02-01

    Calf venous compliance (C calf) is commonly evaluated with venous occlusion plethysmography (VOP) during a standard cuff deflation protocol. However, the technique relies on two not previously validated assumptions concerning thigh cuff pressure (P cuff) transmission and the impact of net fluid filtration (F filt) on C calf. The aim was to validate VOP in the lower limb and to develop a model to correct for F filt during VOP. Strain-gauge technique was used to study calf volume changes in 15 women and 10 age-matched men. A thigh cuff was inflated to 60 mmHg for 4 and 8 min with a subsequent decrease of 1 mmHg s(-1). Intravenous pressure (P iv) was measured simultaneously. C calf was determined with the commonly used equation [Compliance = β 1 + 2β 2 × P cuff] describing the pressure-compliance relationship. A model was developed to identify and correct for F filt. Transmission of P cuff to P iv was 100 %. The decrease in P cuff correlated well with P iv reduction (r = 0.99, P < 0.001). Overall, our model showed that C calf was underestimated when F filt was not accounted for (all P < 0.01). F filt was higher in women (P < 0.01) and showed a more pronounced effect on C calf compared to men (P < 0.05). The impact of F filt was similar during 4- and 8-min VOP. P cuff is an adequate substitute for P iv in the lower limb. F filt is associated with an underestimation of C calf and differences in the effect of F filt during VOP can be accounted for with the correction model. Thus, our model seems to be a valuable tool in future studies of venous wall function.

  3. [Developmental venous anomaly (DVA)].

    Science.gov (United States)

    Zimmer, A; Hagen, T; Ahlhelm, F; Viera, J; Reith, W; Schulte-Altedorneburg, G

    2007-10-01

    As congenital anatomic variants of venous drainage, developmental venous anomalies (DVA) represent up to 60% of all cerebral vascular malformations. The prior term "venous angioma" is a misnomer implicating an abnormal vascular structure with an increased bleeding risk. They are often found incidentally and are hardly ever symptomatic. Their morphologic characteristics are dilated vessels in the white matter, which converge on a greater collector vein, forming the typical caput medusae. They drain into the superficial or deep venous system. The frequent association with other, potentially bleeding-prone vascular malformations is clinically relevant, in particular cavernous angioma, which might require therapeutic action. Therefore, coincident vascular lesions need to be actively sought by appropriate additional imaging techniques.

  4. Venous ulcer review

    Science.gov (United States)

    Bevis, Paul; Earnshaw, Jonothan

    2011-01-01

    Clinical question: What is the best treatment for venous ulcers? Results: Compression aids ulcer healing. Pentoxifylline can aid ulcer healing. Artificial skin grafts are more effective than other skin grafts in helping ulcer healing. Correction of underlying venous incompetence reduces ulcer recurrence. Implementation: Potential pitfalls to avoid are: Failure to exclude underlying arterial disease before application of compression.Unusual-looking ulcers or those slow to heal should be biopsied to exclude malignant transformation. PMID:21673869

  5. Venous ulcer review

    OpenAIRE

    Bevis, Paul; Earnshaw, Jonothan

    2011-01-01

    Paul Bevis, Jonothan Earnshaw Department of Vascular Surgery, Gloucestershire Royal Hospital, Great Western Road, Gloucester, UKDate of preparation: 3 February 2011Conflict of interest: None declared.Clinical question: What is the best treatment for venous ulcers?Results: Compression aids ulcer healing. Pentoxifylline can aid ulcer healing. Artificial skin grafts are more effective than other skin grafts in helping ulcer healing. Correction of underlying venous incompetence reduces ulcer recu...

  6. Ultrasound Vascular Elastography as a Tool for Assessing Atherosclerotic Plaques

    DEFF Research Database (Denmark)

    Mahmood, Badar; Ewertsen, C; Carlsen, Jørn

    2016-01-01

    Library and Web of Science databases. A standardized template was used to extract relevant data following the PRISMA 2009 checklist. 20 articles were included in this paper. The studies were heterogeneous. All studies reported that elastography was a feasible technique and provided additional information...

  7. Suture granuloma after orchiectomy: sonography, doppler and elastography features

    Directory of Open Access Journals (Sweden)

    Mustafa Secil

    2015-08-01

    Full Text Available ABSTRACTSuture granuloma is a mass forming benign lesion that develops at the site of surgery as a foreign body reaction to non-absorbable suture material. We present a case of suture granuloma that developed at the inguinal region after orchiectomy, and define the sonography, color Doppler sonography and real-time ultrasound elastography findings in correlation with the histopathological findings.

  8. Ultrasound Elastography: Review of Techniques and Clinical Applications

    Science.gov (United States)

    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

  9. Ultrasound elastography for imaging tendons and muscles

    Directory of Open Access Journals (Sweden)

    Elena Drakonaki

    2012-06-01

    Full Text Available Ultrasound elastography is a recently developed ultrasound-based method which allows the qualitative or quantitative evaluation of the mechanical properties of tissue. Strain (compression ultrasound elastography is the commonest technique performed by ap‑ plying mild compression with the hand-held transducer to create real-time strain dis‑ tribution maps, which are color-coded and superimposed on the B-mode images. There is increasing evidence that ultrasound elastography can be used in the investigation of muscle, tendon and soft tissue disease in the clinical practice, as a supplementary tool to conventional ultrasound examination. Based on preliminary data, potential clinical appli‑ cations include early diagnosis, staging, and guiding interventions musculotendinous and neuromuscular disease as well as monitoring disease during rehabilitation. Ultrasound elastography could also be used for research into the biomechanics and pathophysiology of musculotendinous disease. Despite the great interest in the technique, there is still limited evidence in the literature and there are several technical issues which limit the reproducibility of the method, including differences in quantification methods, artefacts, limitations and variation in the application of the technique by different users. This re‑ view presents the published evidence on musculoskeletal applications of strain elastogra‑ phy, discusses the technical issues and future perspectives of this method and emphasizes the need for standardization and further research.

  10. Cardiac magnetic resonance elastography. Initial results.

    Science.gov (United States)

    Elgeti, Thomas; Rump, Jens; Hamhaber, Uwe; Papazoglou, Sebastian; Hamm, Bernd; Braun, Jürgen; Sack, Ingolf

    2008-11-01

    To develop cardiac magnetic resonance elastography (MRE) for noninvasively measuring left ventricular (LV) pressure-volume (P-V) work. The anterior chest wall of 8 healthy volunteers was vibrated by 24.3-Hz acoustic waves for stimulating oscillating shear deformation in myocardium and adjacent blood. The induced motion was recorded by an electrocardiogram-gated, vibration-synchronized and segmented gradient-recalled echo MRE sequence acquiring 360 phase-contrast wave images with a temporal resolution of 5.16 milliseconds in the short-axis view during controlled breathing. Relative changes in wave amplitudes served as a measure of LV pressure variation during the cardiac cycle. MRE pressure data were combined with LV volumes obtained from segmentation of 3D cine-steady-state free precession data sets. Shear wave amplitudes decreased from diastole to systole, which reflects the dynamics of myocardial shear modulus variations during the cardiac cycle. Assuming spherical shear stress, a linear relationship between myocardial stiffness and LV pressure was derived. The MRE-measured pressure was plotted as a function of LV volumes. Characteristic P-V cycles displayed an isovolumetric increase in pressure during early systole, whereas less pronounced volume conservation was observed in early diastole. Mean cardiac P-V work in all volunteers was 0.85 +/- 0.11 J. In vivo cardiac MRE is a noninvasive method for measuring pressure-related heart function determined by shear modulus variations in the LV wall. This is the first noninvasive mechanical test of cardiac work in the human heart and is potentially useful for assessing pathologies associated with increased myocardial stiffness such as diastolic dysfunction.

  11. Ultrasound elastography using empirical mode decomposition analysis.

    Science.gov (United States)

    Sadeghi, Sajjad; Behnam, Hamid; Tavakkoli, Jahan

    2014-01-01

    Ultrasound elastography is a non-invasive method which images the elasticity of soft-tissues. To make an image, pre and after a small compression, ultrasound radio frequency (RF) signals are acquired and the time delays between them are estimated. The first differentiation of displacement estimations is called elastogram. In this study, we are going to make an elastogram using the processing method named empirical mode decomposition (EMD). EMD is an analytic technique which decomposes a complicated signal to a collection of simple signals called intrinsic mode functions (IMFs). The idea of paper is using these IMFs instead of primary RF signals. To implement the algorithms two different datasets selected. The first one was data from a sandwich structure of normal and cooked tissue. The second dataset consisted of around 180 frames acquired from a malignant breast tumor. For displacement estimating, two different methods, cross-correlation and wavelet transform, were used too and for evaluating the quality, two conventional parameters, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) calculated for each image. Results show that in both methods after using EMD the quality improves. In first dataset and cross correlation technique CNR and SNR improve about 16 dB and 9 dB respectively. In same dataset by using wavelet technique, the parameters show 14 dB and 10 dB improvement respectively. In second dataset (breast tumor data) CNR and SNR in cross correlation method improve 18 dB and 7 dB and in wavelet technique improve 17 dB and 6 dB respectively.

  12. Shear wave elastography versus real-time elastography on evaluation thyroid nodules: A preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Bao-Xian, E-mail: xian_1121@163.com [Department of Medical Ultrasonics, the First Affiliated Hospital of Sun Yat-sen University, Institute of Diagnostic and Interventional Ultrasound, Sun Yat-Sen University, 58 Zhong Shan Road 2, Guangzhou 510080 (China); Xie, Xiao-Yan, E-mail: xxy1992@21cn.com [Department of Medical Ultrasonics, the First Affiliated Hospital of Sun Yat-sen University, Institute of Diagnostic and Interventional Ultrasound, Sun Yat-Sen University, 58 Zhong Shan Road 2, Guangzhou 510080 (China); Liang, Jin-Yu, E-mail: fishgrace1124@gmail.com [Department of Medical Ultrasonics, the First Affiliated Hospital of Sun Yat-sen University, Institute of Diagnostic and Interventional Ultrasound, Sun Yat-Sen University, 58 Zhong Shan Road 2, Guangzhou 510080 (China); Zheng, Yan-Ling, E-mail: zhyanl@mail.sysu.edu.cn [Department of Medical Ultrasonics, the First Affiliated Hospital of Sun Yat-sen University, Institute of Diagnostic and Interventional Ultrasound, Sun Yat-Sen University, 58 Zhong Shan Road 2, Guangzhou 510080 (China); Huang, Guang-Liang, E-mail: venice0016@163.com [Department of Medical Ultrasonics, the First Affiliated Hospital of Sun Yat-sen University, Institute of Diagnostic and Interventional Ultrasound, Sun Yat-Sen University, 58 Zhong Shan Road 2, Guangzhou 510080 (China); Zhou, Lu-Yao, E-mail: 5454kill@163.com [Department of Medical Ultrasonics, the First Affiliated Hospital of Sun Yat-sen University, Institute of Diagnostic and Interventional Ultrasound, Sun Yat-Sen University, 58 Zhong Shan Road 2, Guangzhou 510080 (China); Wang, Zhu, E-mail: 160395191@qq.com [Department of Medical Ultrasonics, the First Affiliated Hospital of Sun Yat-sen University, Institute of Diagnostic and Interventional Ultrasound, Sun Yat-Sen University, 58 Zhong Shan Road 2, Guangzhou 510080 (China); and others

    2014-07-15

    Objective: To comparatively evaluate shear wave elastography (SWE) and real-time elastography (RTE) in distinguishing malignant from benign thyroid nodules. Methods: 49 patients with 64 focal thyroid nodules were enrolled and underwent SWE and RTE before surgery. SWE elasticity indices (mean, minimum and maximum value of 2-mm region of interest) of nodules were measured. For RTE, elastograms were assessed by Rago criteria and nodules with scores of 4 or 5 were classified as suspicious for malignancy. Surgery histopathologic results were adopted as diagnostic standard. Results: Of the 64 nodules, 19 were papillary thyroid carcinomas and 45 were benign. SWE indices were significantly higher in malignant than benign nodules (P < 0.05). Areas under the ROC curves (AUC) of SWE parameters were 0.840, 0.831 and 0.788, which were not significantly different from that of RTE showed as 0.880 (P = 0.148–0.482). When the most accurate cut-off, 38.3 kPa for mean value was applied to predict malignancy, the diagnostic specificity, sensitivity, accuracy, positive predictive value and negative predictive value of SWE and RTE were 68.4% versus 79.0%, 86.7% versus 84.4%, 81.3% versus 78.1%, 68.4% versus 64.7% and 86.7% versus 83.3%, respectively (P = 0.683–1.000). Conclusion: SWE as a promising tool can be performed in differentiating thyroid nodules with comparable results to RTE.

  13. Evaluation of tomosynthesis elastography in a breast-mimicking phantom

    Energy Technology Data Exchange (ETDEWEB)

    Engelken, Florian Jan, E-mail: florian.engelken@charite.de [Department of Radiology, Charité Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin (Germany); Sack, Ingolf, E-mail: ingolf.sack@charite.de [Department of Radiology, Charité Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin (Germany); Klatt, Dieter, E-mail: dieter.klatt@charite.de [Department of Radiology, Charité Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin (Germany); Fischer, Thomas, E-mail: thom.fischer@charite.de [Department of Radiology, Charité Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin (Germany); Fallenberg, Eva Maria, E-mail: eva.fallenberg@charite.de [Department of Radiology, Charité Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin (Germany); Bick, Ulrich, E-mail: ulrich.bick@charite.de [Department of Radiology, Charité Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin (Germany); Diekmann, Felix, E-mail: felix.diekmann@charite.de [Department of Radiology, Charité Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin (Germany)

    2012-09-15

    Objective: To evaluate whether measurement of strain under static compression in tomosynthesis of a breast-mimicking phantom can be used to distinguish tumor-simulating lesions of different elasticities and to compare the results to values predicted by rheometric analysis as well as results of ultrasound elastography. Materials and methods: We prepared three soft breast-mimicking phantoms containing simulated tumors of different elasticities. The phantoms were imaged using a wide angle tomosynthesis system with increasing compression settings ranging from 0 N to 105 N in steps of 15 N. Strain of the inclusions was measured in two planes using a commercially available mammography workstation. The elasticity of the phantom matrix and inclusion material was determined by rheometric analysis. Ultrasound elastography of the inclusions was performed using two different ultrasound elastography algorithms. Results: Strain at maximal compression was 24.4%/24.5% in plane 1/plane 2, respectively, for the soft inclusion, 19.6%/16.9% for the intermediate inclusion, and 6.0%/10.2% for the firm inclusion. The strain ratios predicted by rheometrical testing were 0.41, 0.83 and 1.26 for the soft, intermediate, and firm inclusions, respectively. The strain ratios obtained for the soft, intermediate, and firm inclusions were 0.72 ± 0.13, 1.02 ± 0.21 and 2.67 ± 1.70, respectively for tomosynthesis elastography, 0.91, 1.64 and 2.07, respectively, for ultrasound tissue strain imaging, and 0.97, 2.06 and 2.37, respectively, for ultrasound real-time elastography. Conclusions: Differentiation of tumor-simulating inclusions by elasticity in a breast mimicking phantom may be possible by measuring strain in tomosynthesis. This method may be useful for assessing elasticity of breast lesions tomosynthesis of the breast.

  14. In vivo study of myocardial elastography under graded ischemia conditions

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Wei-Ning; Provost, Jean; Konofagou, Elisa E [Department of Biomedical Engineering, Columbia University, New York, NY (United States); Fujikura, Kana [Department of Radiology, Columbia University, New York, NY (United States); Wang Jie, E-mail: ek2191@columbia.edu [Department of Medicine, Columbia University, New York, NY (United States)

    2011-02-21

    The capability of currently available echocardiography-based strain estimation techniques to fully map myocardial abnormality at early stages of myocardial ischemia is yet to be investigated. In this study, myocardial elastography (ME), a radio-frequency (RF)-based strain imaging technique that maps the full 2D transmural angle-independent strain tensor in standard echocardiographic views at both high spatial and temporal resolution is presented. The objectives were to (1) evaluate the performance of ME on mapping the onset, extent and progression of myocardial ischemia at graded coronary constriction levels (from partial to complete coronary flow reduction), and (2) validate the accuracy of the strain estimates against sonomicrometry (SM) measurements. A non-survival canine ischemic model (n = 5) was performed by gradually constricting the left anterior descending (LAD) coronary blood flow from 0% (baseline blood flow) to 100% (zero blood flow) at 20% increments. An open-architecture ultrasound system was used to acquire RF echocardiograms in a standard full short-axis view at the frame rate of 211 fps, at least twice higher than what is typically used in conventional echocardiographic systems, using a previously developed, fully automated composite technique. Myocardial deformation was estimated by ME and validated against sonomicrometry. ME estimates and maps transmural (1) 2D displacements using RF cross-correlation and recorrelation; and (2) 2D polar (radial and circumferential) strains, derived from 2D (i.e. both lateral and axial) displacement components, at high accuracy. Full-view strain images were shown and found to reliably depict decreased myocardial function in the region at risk at increased levels of coronary flow reduction. The ME radial strain was deemed to be a more sensitive, quantitative, regional measure of myocardial ischemia as a result of coronary flow reduction when compared to the conventional wall motion score index and ejection fraction

  15. In vivo study of myocardial elastography under graded ischemia conditions

    Science.gov (United States)

    Lee, Wei-Ning; Provost, Jean; Fujikura, Kana; Wang, Jie; Konofagou, Elisa E.

    2011-02-01

    The capability of currently available echocardiography-based strain estimation techniques to fully map myocardial abnormality at early stages of myocardial ischemia is yet to be investigated. In this study, myocardial elastography (ME), a radio-frequency (RF)-based strain imaging technique that maps the full 2D transmural angle-independent strain tensor in standard echocardiographic views at both high spatial and temporal resolution is presented. The objectives were to (1) evaluate the performance of ME on mapping the onset, extent and progression of myocardial ischemia at graded coronary constriction levels (from partial to complete coronary flow reduction), and (2) validate the accuracy of the strain estimates against sonomicrometry (SM) measurements. A non-survival canine ischemic model (n = 5) was performed by gradually constricting the left anterior descending (LAD) coronary blood flow from 0% (baseline blood flow) to 100% (zero blood flow) at 20% increments. An open-architecture ultrasound system was used to acquire RF echocardiograms in a standard full short-axis view at the frame rate of 211 fps, at least twice higher than what is typically used in conventional echocardiographic systems, using a previously developed, fully automated composite technique. Myocardial deformation was estimated by ME and validated against sonomicrometry. ME estimates and maps transmural (1) 2D displacements using RF cross-correlation and recorrelation; and (2) 2D polar (radial and circumferential) strains, derived from 2D (i.e. both lateral and axial) displacement components, at high accuracy. Full-view strain images were shown and found to reliably depict decreased myocardial function in the region at risk at increased levels of coronary flow reduction. The ME radial strain was deemed to be a more sensitive, quantitative, regional measure of myocardial ischemia as a result of coronary flow reduction when compared to the conventional wall motion score index and ejection fraction

  16. Quantitative assessment of corneal viscoelasticity using optical coherence elastography and a modified Rayleigh-Lamb equation

    Science.gov (United States)

    Han, Zhaolong; Aglyamov, Salavat R.; Li, Jiasong; Singh, Manmohan; Wang, Shang; Vantipalli, Srilatha; Wu, Chen; Liu, Chih-hao; Twa, Michael D.; Larin, Kirill V.

    2015-02-01

    We demonstrate the use of a modified Rayleigh-Lamb frequency equation in conjunction with noncontact optical coherence elastography to quantify the viscoelastic properties of the cornea. Phase velocities of air-pulse-induced elastic waves were extracted by spectral analysis and used for calculating the Young's moduli of the samples using the Rayleigh-Lamb frequency equation (RLFE). Validation experiments were performed on 2% agar phantoms (n=3) and then applied to porcine corneas (n=3) in situ. The Young's moduli of the porcine corneas were estimated to be ˜60 kPa with a shear viscosity ˜0.33 Pa.s. The results demonstrate that the RLFE is a promising method for noninvasive quantification of the corneal biomechanical properties and may potentially be useful for clinical ophthalmological applications.

  17. Recovering vector displacement estimates in quasistatic elastography using sparse relaxation of the momentum equation

    CERN Document Server

    Babaniyi, Olalekan A; Barbone, Paul E

    2015-01-01

    We consider the problem of estimating the $2D$ vector displacement field in a heterogeneous elastic solid deforming under plane stress conditions. The problem is motivated by applications in quasistatic elastography. From precise and accurate measurements of one component of the $2D$ vector displacement field and very limited information of the second component, the method reconstructs the second component quite accurately. No a priori knowledge of the heterogeneous distribution of material properties is required. This method relies on using a special form of the momentum equations to filter ultrasound displacement measurements to produce more precise estimates. We verify the method with applications to simulated displacement data. We validate the method with applications to displacement data measured from a tissue mimicking phantom, and in-vivo data; significant improvements are noticed in the filtered displacements recovered from all the tests. In verification studies, error in lateral displacement estimate...

  18. Musculoskeletal Applications of Elastography: a Pictorial Essay of Our Initial Experience

    OpenAIRE

    Lalitha, Palle; Reddy, M.Ch. Balaji; Reddy, K.Jagannath

    2011-01-01

    Elastography is an ultrasound-based newer imaging technique that is currently being used for the evaluation of breast lesions and hepatic pathology. It is also being evaluated for characterizing lesions of the prostate, thyroid, cervix and lymph nodes. We have applied real-time sonoelastography to a variety of musculoskeletal pathologies and here we report the findings of elastography for the evaluation of various musculoskeletal pathologies. Elastography of musculoskeletal lesions is not yet...

  19. Trans-vaginal sono-elastography in the differentiation of endometrial hyperplasia and endometrial carcinoma

    OpenAIRE

    Mahmoud Abdel Latif; Magda Shady; Hanan Nabil; Yasser Mesbah

    2016-01-01

    Aim: To evaluate efficiency of sono-elastography in differentiation of endometrial hyperplasia and endometrial carcinoma. Patients and methods: Between January 2014 and January 2015, 45 perimenopausal female patients with endometrial thickness more than 6 mm were examined by TV sono-elastography procedure. Results of ultrasound and elastography were compared with pathological data (reference standard). Strain ratios were compared between typical, atypical endometrial hyperplasia and endome...

  20. Ultrasound Shear Wave Elastography for Liver Disease. A Critical Appraisal of the Many Actors on the Stage.

    Science.gov (United States)

    Piscaglia, F; Salvatore, V; Mulazzani, L; Cantisani, V; Schiavone, C

    2016-02-01

    measuring both liver 13 and spleen stiffness, which is a new application of elastography 14, of interest for the prediction of the degree of portal hypertension 15 16.Nowadays other companies have started producing equipment with pSWE technology, but only very few articles have been published so far, for instance describing the use of Philips(®) equipment, which was the second to provide pSWE. These articles show preliminary good results also in comparison with TE 17 18. Not enough evidence is currently available in the literature about the elastographic performance of the products most recently introduced to the market. Furthermore, with some products the shear wave velocities generated by a single ultrasound acoustic push pulse can be measured in a bidimensional area (a box in the range of 2 - 3 cm per side) rather than in a single small point, producing a so-called bidimensional 2D-SWE 1. The stiffness is depicted in color within the area and refreshing of the measurement occurs every 1 - 2 seconds. Once the best image is acquired, the operator chooses a Region Of Interest (ROI) within the color box, where the mean stiffness is then calculated. 2D-SWE can be performed as a "one shot" technique or as a semi-"real-time" technique for a few seconds (at about 1 frame per second) in order to obtain a stable elastogram. With either technique, there should be no motion/breathing during image acquisition. A bidimensional averaged area should overcome the limitation of pSWE to inadvertently investigate small regions of greater or lesser stiffness than average. A shear wave quality indicator could be useful to provide real-time feedback and optimize placement of the sampling ROIs, a technology recently presented by Toshiba(®), but which is still awaiting validation in the literature.Supersonic Imagine by Aixplorer(®) which works with a different modality of insonation and video analysis compared to the the previously-mentioned three techniques (i. e., transient

  1. A novel breast software phantom for biomechanical modeling of elastography.

    Science.gov (United States)

    Bhatti, Syeda Naema; Sridhar-Keralapura, Mallika

    2012-04-01

    In developing breast imaging technologies, testing is done with phantoms. Physical phantoms are normally used but their size, shape, composition, and detail cannot be modified readily. These difficulties can be avoided by creating a software breast phantom. Researchers have created software breast phantoms using geometric and/or mathematical methods for applications like image fusion. The authors report a 3D software breast phantom that was built using a mechanical design tool, to investigate the biomechanics of elastography using finite element modeling (FEM). The authors propose this phantom as an intermediate assessment tool for elastography simulation; for use after testing with commonly used phantoms and before clinical testing. The authors design the phantom to be flexible in both, the breast geometry and biomechanical parameters, to make it a useful tool for elastography simulation. The authors develop the 3D software phantom using a mechanical design tool based on illustrations of normal breast anatomy. The software phantom does not use geometric primitives or imaging data. The authors discuss how to create this phantom and how to modify it. The authors demonstrate a typical elastography experiment of applying a static stress to the top surface of the breast just above a simulated tumor and calculate normal strains in 3D and in 2D with plane strain approximations with linear solvers. In particular, they investigate contrast transfer efficiency (CTE) by designing a parametric study based on location, shape, and stiffness of simulated tumors. The authors also compare their findings to a commonly used elastography phantom. The 3D breast software phantom is flexible in shape, size, and location of tumors, glandular to fatty content, and the ductal structure. Residual modulus, maps, and profiles, served as a guide to optimize meshing of this geometrically nonlinear phantom for biomechanical modeling of elastography. At best, low residues (around 1-5 KPa) were

  2. Venous thromboembolism in pregnancy and the puerperal period: a study of 1210 events

    DEFF Research Database (Denmark)

    Virkus, Rie Adser; Løkkegaard, Ellen Cl; Lidegaard, Ojvind

    2013-01-01

    The aim of this study was to describe venous thromboembolism (VTE) in pregnancy and the puerperal period and to validate diagnoses of VTE.......The aim of this study was to describe venous thromboembolism (VTE) in pregnancy and the puerperal period and to validate diagnoses of VTE....

  3. Hormonal contraception and venous thromboembolism

    DEFF Research Database (Denmark)

    Lidegaard, Øjvind; Milsom, Ian; Geirsson, Reynir Tomas

    2012-01-01

    New studies about the influence of hormonal contraception on the risk of venous thromboembolism (VTE) have been published.......New studies about the influence of hormonal contraception on the risk of venous thromboembolism (VTE) have been published....

  4. Transient elastography: Kill two birds with one stone?

    Science.gov (United States)

    Wong, Grace Lai-Hung

    2013-01-01

    Assessment of liver fibrosis and steatosis is crucial in chronic liver diseases in order to determine the prognosis, the need of treatment, as well as monitor disease progression and response to treatment. Liver biopsy is limited by its invasiveness and patient acceptability. Transient elastography (TE, Fibroscan®) is a non-invasive tool with satisfactory accuracy and reproducibility to estimate liver fibrosis and steatosis. TE has been well validated in major liver diseases including chronic hepatitis B and C, non-alcoholic fatty liver disease, alcoholic liver disease, primary biliary cirrhosis, and primary sclerosing cholangitis. As alanine aminotransferase (ALT) is one of the major confounding factors of liver stiffness in chronic hepatitis B, an ALT-based algorithm has been developed and higher liver stiffness measurements (LSM) cutoff values for different stages of liver fibrosis should be used in patients with elevated ALT levels up to 5 times of the upper limit of normal. Otherwise falsely-high LSM results up to cirrhotic range may occur during ALT flare. TE is also useful in predicting patient prognosis such as development of hepatocellular carcinoma (HCC), portal hypertension, post-operative complications in HCC patients, and also survival. Unfortunately, failed acquisition of TE is common in obese patients. Furthermore, obese patients may have higher LSM results even in the same stage of liver fibrosis. The new XL probe, a larger probe with lower ultrasound frequency and deeper penetration, increases the success rate of TE in obese patients. The median LSM value with XL probe was found to be lower than that by the conventional M probe, hence cutoff values approximately 1.2 to 1.3 kPa lower than those of M probe should be adopted. Recent studies revealed a novel ultrasonic controlled attenuation parameter (CAP) of the machine is a useful parameter to detect even low-grade steatosis noninvasively. CAP may also be used to quantify liver steatosis by

  5. Multicentre validation of the Geneva Risk Score for hospitalised medical patients at risk of venous thromboembolism. Explicit ASsessment of Thromboembolic RIsk and Prophylaxis for Medical PATients in SwitzErland (ESTIMATE).

    Science.gov (United States)

    Nendaz, M; Spirk, D; Kucher, N; Aujesky, D; Hayoz, D; Beer, J H; Husmann, M; Frauchiger, B; Korte, W; Wuillemin, W A; Jäger, K; Righini, M; Bounameaux, H

    2014-03-03

    There is a need to validate risk assessment tools for hospitalised medical patients at risk of venous thromboembolism (VTE). We investigated whether a predefined cut-off of the Geneva Risk Score, as compared to the Padua Prediction Score, accurately distinguishes low-risk from high-risk patients regardless of the use of thromboprophylaxis. In the multicentre, prospective Explicit ASsessment of Thromboembolic RIsk and Prophylaxis for Medical PATients in SwitzErland (ESTIMATE) cohort study, 1,478 hospitalised medical patients were enrolled of whom 637 (43%) did not receive thromboprophylaxis. The primary endpoint was symptomatic VTE or VTE-related death at 90 days. The study is registered at ClinicalTrials.gov, number NCT01277536. According to the Geneva Risk Score, the cumulative rate of the primary endpoint was 3.2% (95% confidence interval [CI] 2.2-4.6%) in 962 high-risk vs 0.6% (95% CI 0.2-1.9%) in 516 low-risk patients (p=0.002); among patients without prophylaxis, this rate was 3.5% vs 0.8% (p=0.029), respectively. In comparison, the Padua Prediction Score yielded a cumulative rate of the primary endpoint of 3.5% (95% CI 2.3-5.3%) in 714 high-risk vs 1.1% (95% CI 0.6-2.3%) in 764 low-risk patients (p=0.002); among patients without prophylaxis, this rate was 3.2% vs 1.5% (p=0.130), respectively. Negative likelihood ratio was 0.28 (95% CI 0.10-0.83) for the Geneva Risk Score and 0.51 (95% CI 0.28-0.93) for the Padua Prediction Score. In conclusion, among hospitalised medical patients, the Geneva Risk Score predicted VTE and VTE-related mortality and compared favourably with the Padua Prediction Score, particularly for its accuracy to identify low-risk patients who do not require thromboprophylaxis.

  6. Models of the venous system

    DEFF Research Database (Denmark)

    Mehlsen, J

    2000-01-01

    of the venous system require at least three elements: a resistor, a capacitor and an inductor, with the latter being of more importance in the venous than in the arterial system. Non-linearities must be considered in pressure/flow relations in the small venules, during venous collapse, or low flow conditions...

  7. Venous oxygen saturation.

    Science.gov (United States)

    Hartog, Christiane; Bloos, Frank

    2014-12-01

    Early detection and rapid treatment of tissue hypoxia are important goals. Venous oxygen saturation is an indirect index of global oxygen supply-to-demand ratio. Central venous oxygen saturation (ScvO2) measurement has become a surrogate for mixed venous oxygen saturation (SvO2). ScvO2 is measured by a catheter placed in the superior vena cava. After results from a single-center study suggested that maintaining ScvO2 values >70% might improve survival rates in septic patients, international practice guidelines included this target in a bundle strategy to treat early sepsis. However, a recent multicenter study with >1500 patients found that the use of central hemodynamic and ScvO2 monitoring did not improve long-term survival when compared to the clinical assessment of the adequacy of circulation. It seems that if sepsis is recognized early, a rapid initiation of antibiotics and adequate fluid resuscitation are more important than measuring venous oxygen saturation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Magnetic resonance elastography (MRE) in cancer: Technique, analysis, and applications

    Science.gov (United States)

    Pepin, Kay M.; Ehman, Richard L.; McGee, Kiaran P.

    2015-01-01

    Tissue mechanical properties are significantly altered with the development of cancer. Magnetic resonance elastography (MRE) is a noninvasive technique capable of quantifying tissue mechanical properties in vivo. This review describes the basic principles of MRE and introduces some of the many promising MRE methods that have been developed for the detection and characterization of cancer, evaluation of response to therapy, and investigation of the underlying mechanical mechanisms associated with malignancy. PMID:26592944

  9. Association between kidney intracapsular pressure and ultrasound elastography

    OpenAIRE

    Kashani, Kianoush B.; Mao, Shennen A; Safadi, Sami; Amiot, Bruce P.; Glorioso, Jaime M; Lieske, John C.; Nyberg, Scott L.; Zhang, Xiaoming

    2017-01-01

    Background Kidney congestion is a common pathophysiologic pathway of acute kidney injury (AKI) in sepsis and heart failure. There is no noninvasive tool to measure kidney intracapsular pressure (KIP) directly. Methods We evaluated the correlation of KIP with kidney elasticity measured by ultrasound surface wave elastography (USWE). We directly measured transcatheter KIP in three pigs at baseline and after bolus infusion of normal saline, norepinephrine, vasopressin, dopamine, and fenoldopam; ...

  10. Improvement of Lesion Detection by Complete Angular Compound Ultrasonic Elastography.

    Science.gov (United States)

    Liu, Chenhui; Zhou, Yufeng

    2016-01-24

    Quasi -: static ultrasound elastography is an emerging diagnostic imaging modality for determining the stiffness of pathologically changed soft tissues, which do not show significant differences in acoustic impedance for B-mode imaging. Although some methods were applied to improve the signal-to-noise ratio (SNRe) and contrast-to-noise ratio (CNRe) of the constructed elastogram, nonuniform strain distribution at the internal boundary of a hard inclusion, even with the uniform displacement on the surface, is an inherent mechanical effect and results in distortion at the detected lesion boundary. To overcome such stress concentrations, a new elastographic modality was proposed, where the elastograms from different angles throughout 360° were compounded. The strain field and subsequent ultrasound images were calculated using the finite element method (FEM) and Field II, respectively, from which the elastograms were constructed. The performance of complete angular compound elastography with varied interval angles, lesion sizes, and ratios of Young's moduli of the lesion to the background was simulated and compared with that of conventional axial strain elastography. It is found that viewing the lesion from only about 10 angles (interval of 36°) would significantly improve the image quality of elastogram (increasing SNRe by at least 13% and CNRe by at least 5.8 dB), reduce the lesion distortion in the lateral direction, and enhance the sensitivity, resolution, and accuracy of lesion detection. A preliminary phantom study showed similar improvements. Altogether, complete angular compound elastography improves the elastogram quality and reduces the mechanical effects in lesion detection. © The Author(s) 2016.

  11. Breast mass evaluation: factors influencing the quality of US elastography.

    Science.gov (United States)

    Chang, Jung Min; Moon, Woo Kyung; Cho, Nariya; Kim, Seung Ja

    2011-04-01

    To investigate factors influencing the quality of ultrasonographic (US) elastography in the evaluation of suspicious breast masses. This prospective study was conducted with institutional review board approval; written informed consent was obtained. Between January 2009 and February 2009, real-time US elastography of 312 breast masses (245 benign, 67 malignant) was performed in 268 consecutive patients (mean age, 45.7 years ± 10.2 [standard deviation]) prior to US-guided core biopsy. Five breast radiologists who had performed the examinations assessed the quality of elasticity images as inadequate, low, or high without histologic information. Age, body mass index (BMI), mammographic density, lesion size, lesion depth, and breast thickness at US were analyzed for their association with image quality by using the χ(2) test, Student t test, and multivariate analysis. Sensitivities and specificities for the differentiation of benign from malignant masses on the basis of elastography were calculated and compared between groups of quality scores by using the logistic regression method. The quality of elasticity images was assessed as inadequate in 21 (6.7%) cases, low in 134 (42.9%), and high in 157 (50.3%). According to univariate analysis, smaller lesion size (P = .001), shallower lesion depth (P = .005), less breast thickness where the lesion was located (P image quality. There was no correlation of image quality with age (P = .213), BMI (P = .191), mammographic density (P = .091), or distance from the nipple (P = .100). Multivariable analysis showed that breast thickness at the location of target lesions was the most important factor influencing elasticity image quality (P = .001). There were significant differences in sensitivity between higher-quality and lower-quality images (87.0% vs 56.8%, respectively; P = .015) in the differentiation of benign from malignant masses. Breast thickness at the location of the lesion was the most important factor influencing

  12. Quantitative photoacoustic elastography of Young's modulus in humans

    Science.gov (United States)

    Hai, Pengfei; Zhou, Yong; Gong, Lei; Wang, Lihong V.

    2017-03-01

    Elastography can noninvasively map the elasticity distribution of biological tissue, which is often altered in pathological states. In this work, we report quantitative photoacoustic elastography (QPAE), capable of measuring Young's modulus of human tissue in vivo. By combining photoacoustic elastography with a stress sensor having known stress-strain behavior, QPAE can simultaneously measure strain and stress, from which Young's modulus is calculated. We first applied QPAE to quantify the Young's modulus of tissue-mimicking agar phantoms with different concentrations. The measured values fitted well with both the empirical expectations based on the agar concentrations and those measured in independent standard compression tests. We then demonstrated the feasibility of QPAE by measuring the Young's modulus of human skeletal muscle in vivo. The data showed a linear relationship between muscle stiffness and loading. The results proved that QPAE can noninvasively quantify the absolute elasticity of biological tissue, thus enabling longitudinal imaging of tissue elasticity. QPAE can be exploited for both preclinical biomechanics studies and clinical applications.

  13. The aetiology of deep venous thrombosis.

    Science.gov (United States)

    Malone, P C; Agutter, P S

    2006-09-01

    Most ideas about the pathogenesis of deep venous thrombosis (DVT) are dominated by a 'consensus model' first articulated around 1962. This model invokes 'Virchow's triad' and attributes thrombogenesis in veins to some combination of 'hypercoagulability', 'stasis' and 'intimal injury'. This arose as a by-product of studies on the mechanisms of haemostasis and bleeding diatheses that were at best only indirectly relevant to thrombosis, and there are reasons for doubting the causal significance of 'hypercoagulability' and 'stasis' in the aetiology of DVT. Proponents of the consensus model make little reference to a substantial literature, mostly historical, that: (a) emphasizes the significance of the venous valve pockets (VVP) and blood rheology in DVT pathogenesis; and (b) describes morphological features specific to venous thrombi that a valid aetiological model must explain. This literature provides the basis for an alternative hypothesis of DVT aetiology, published some 30 years ago, which has been experimentally corroborated and is compatible with recent cell and molecular biological studies of the venous endothelium. We review this alternative hypothesis, considering its potential value for future research on DVT and embolism, and its significance for clinical practice.

  14. Comparison of shear-wave and strain ultrasound elastography in the differentiation of benign and malignant breast lesions.

    Science.gov (United States)

    Chang, Jung Min; Won, Jae-Kyung; Lee, Kyoung-Bun; Park, In Ae; Yi, Ann; Moon, Woo Kyung

    2013-08-01

    The purpose of this article is to compare the diagnostic performances of shearwave and strain elastography for the differentiation of benign and malignant breast lesions. B-mode ultrasound and shear-wave and strain elastography were performed in 150 breast lesions; 71 were malignant. BI-RADS final assessment, elasticity values in kilopascals, and elasticity scores on a 5-point scale were assessed before biopsy. The results were compared using the area under the receiver operating characteristic curve (AUC). The AUC for shear-wave elastography was similar to that of strain elastography (0.928 vs 0.943). The combined use of B-mode ultrasound and either elastography technique improved diagnostic performance in the differentiation of benign and malignant breast lesions compared with the use of B-mode ultrasound alone (B-mode alone, AUC = 0.851; B-mode plus shear-wave elastography, AUC = 0.964; B-mode plus strain elastography, AUC = 0.965; p < 0.001). With the best cutoff points of 80 kPa on shear-wave elastography and a score between 3 and 4 on strain elastography, the sensitivity was higher in shear-wave elastography, and specificity was higher in strain elastography (95.8% vs 81.7%, p = 0.002; 93.7% vs 84.8%, p = 0.016). In cases of infiltrating ductal carcinoma, mean elasticity scores were lower in grade 3 than in grade 1 and 2 cancers (p = 0.017) with strain elastography causing false-negative findings. The diagnostic performance of shear-wave and strain elastography was similar. Either elastography technique can improve overall diagnostic performance in the differentiation of benign and malignant lesions when combined with B-mode ultrasound. However, the sensitivity and specificity of shear-wave and strain elastography were different according to lesion histologic profile, tumor grade, and breast thickness.

  15. Accuracy of endoscopic ultrasound elastography used for differential diagnosis of focal pancreatic masses

    DEFF Research Database (Denmark)

    Săftoiu, A; Vilmann, P; Gorunescu, F

    2011-01-01

    Endoscopic ultrasound (EUS) elastography represents a new imaging procedure that might characterize the differences of hardness and strain between diseased tissue and normal tissue. The aim of this study was to assess the efficiency of EUS elastography for the differentiation of focal masses...

  16. Venous ulcer: what is new?

    Science.gov (United States)

    Raffetto, Joseph D; Marston, William A

    2011-01-01

    The pathophysiology of venous dermal abnormality in chronic venous ulcers is reflective of a complex interplay that involves sustained venous hypertension, inflammation, changes in the microcirculation, cytokine and matrix metalloproteinase activation, and altered cellular function. Red blood cells and macromolecules extravasate into the interstitium and activate endothelial cells. Endothelial expression of specific adhesion molecules recruits leukocytes and causes diapedesis of these cells into the dermal microvasculature, promoting an inflammatory response with activation of cytokines and proteinases. Altered cell function enhances a state of vulnerability in the surrounding tissues, initiating specific changes associated with venous disease. Ultimately, the persistent inflammatory-proteinase activity leads to advanced chronic venous insufficiency and ulcer formation. The mainstay of therapy in venous ulcer abnormality is correction of the underlying venous hypertension through compression therapy and/or surgery. Understanding the science involved in the pathophysiology of venous ulcer formation has led to the development of adjunctive treatment directed at the dysregulated molecular pathways. Randomized clinical trials are critical for determining the most effective evidence-based treatments for venous ulcer, and this review discusses important trials that have had a significant impact on venous ulcer healing. In addition, the authors have included subsections referred to as "Translational Implications for Therapy" in the basic science sections of the review to help bridge the basic science knowledge with clinical applications that may help to modulate the molecular abnormalities in the pathophysiologic cascade leading to venous ulcers.

  17. Comparison of elastography, contrast-enhanced ultrasonography, and computed tomography for assessment of lesion margin after radiofrequency ablation in livers of healthy dogs.

    Science.gov (United States)

    Moon, Sohyeon; Park, Seungjo; Lee, Sang-Kwon; Cheon, Byunggyu; Hong, Sunghwa; Cho, Hyun; Park, Jun-Gyu; Alfajaro, Mia Madel; Cho, Kyoung-Oh; Woo, Dong; Choi, Jihye

    2017-03-01

    OBJECTIVE To assess by use of various diagnostic imaging modalities acute changes in livers of healthy dogs after radiofrequency ablation (RFA) and determine the capability of each imaging modality to monitor ablation lesion changes. ANIMALS 6 healthy Beagles. PROCEDURES 12 ablation lesions were created in the liver of the dogs (2 lesions/dog). Ablation lesions were evaluated by use of conventional ultrasonography, strain elastography, and contrast-enhanced ultrasonography immediately after (time 0), 30 to 60 minutes after, and 3 days after RFA, and by use of CT 30 minutes and 3 days after RFA. Three dogs were euthanized shortly after RFA, and the other 3 dogs were euthanized on day 3. Lesion size measured by each imaging modality was compared with necropsy findings. RESULTS Immediately after RFA, clear margins were more visible with elastography and contrast-enhanced ultrasonography than with conventional ultrasonography, which had acoustic shadowing. On triphasic contrast CT, the ablation zone, which indicated necrosis and hemorrhage, was not enhanced and could be measured. Marked enhancement of the periablation rim was observed during the venous phase and was identified as granulation tissue. Size of the ablation area measured on enhanced CT images was strongly correlated with actual lesion size. CONCLUSIONS AND CLINICAL RELEVANCE For dogs of this study, CT was the most reliable method for lesion size determination. Although ultrasonographic imaging measurements underestimated lesion size, all modalities could be used to provide additional real-time guidance for RFA procedures of the liver as well as for other RFA procedures.

  18. Prospective comparison of liver stiffness measurements between two point wave elastography methods: Virtual ouch quantification and elastography point quantification

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Hyun Suk; Lee, Jeong Min; Yoon, Jeong Hee; Lee, Dong Ho; Chang, Won; Han, Joon Koo [Seoul National University Hospital, Seoul (Korea, Republic of)

    2016-09-15

    To prospectively compare technical success rate and reliable measurements of virtual touch quantification (VTQ) elastography and elastography point quantification (ElastPQ), and to correlate liver stiffness (LS) measurements obtained by the two elastography techniques. Our study included 85 patients, 80 of whom were previously diagnosed with chronic liver disease. The technical success rate and reliable measurements of the two kinds of point shear wave elastography (pSWE) techniques were compared by χ{sup 2} analysis. LS values measured using the two techniques were compared and correlated via Wilcoxon signed-rank test, Spearman correlation coefficient, and 95% Bland-Altman limit of agreement. The intraobserver reproducibility of ElastPQ was determined by 95% Bland-Altman limit of agreement and intraclass correlation coefficient (ICC). The two pSWE techniques showed similar technical success rate (98.8% for VTQ vs. 95.3% for ElastPQ, p = 0.823) and reliable LS measurements (95.3% for VTQ vs. 90.6% for ElastPQ, p = 0.509). The mean LS measurements obtained by VTQ (1.71 ± 0.47 m/s) and ElastPQ (1.66 ± 0.41 m/s) were not significantly different (p = 0.209). The LS measurements obtained by the two techniques showed strong correlation (r = 0.820); in addition, the 95% limit of agreement of the two methods was 27.5% of the mean. Finally, the ICC of repeat ElastPQ measurements was 0.991. Virtual touch quantification and ElastPQ showed similar technical success rate and reliable measurements, with strongly correlated LS measurements. However, the two methods are not interchangeable due to the large limit of agreement.

  19. Efficacy of ultrasound elastography in detecting active myositis in children: can it replace MRI?

    Energy Technology Data Exchange (ETDEWEB)

    Berko, Netanel S.; Levin, Terry L. [Montefiore Medical Center, Department of Radiology, Bronx, NY (United States); Hay, Arielle [Montefiore Medical Center, Department of Pediatrics, Division of Pediatric Rheumatology, Bronx, NY (United States); Miami Children' s Hospital, Department of Pediatrics, Miami, FL (United States); Sterba, Yonit; Wahezi, Dawn [Montefiore Medical Center, Department of Pediatrics, Division of Pediatric Rheumatology, Bronx, NY (United States)

    2015-09-15

    Juvenile idiopathic inflammatory myopathy is a rare yet potentially debilitating condition. MRI is used both for diagnosis and to assess response to treatment. No study has evaluated the performance of US elastography in the diagnosis of this condition in children. To assess the performance of compression-strain US elastography in detecting active myositis in children with clinically confirmed juvenile idiopathic inflammatory myopathy and to compare its efficacy to MRI. Children with juvenile idiopathic inflammatory myopathy underwent non-contrast MR imaging as well as compression-strain US elastography of the quadriceps muscles. Imaging findings from both modalities were compared to each other as well as to the clinical determination of active disease based on physical examination and laboratory data. Active myositis on MR was defined as increased muscle signal on T2-weighted images. Elastography images were defined as normal or abnormal based on a previously published numerical scale of muscle elastography in normal children. Muscle echogenicity was graded as normal or abnormal based on gray-scale sonographic images. Twenty-one studies were conducted in 18 pediatric patients (15 female, 3 male; age range 3-19 years). Active myositis was present on MRI in ten cases. There was a significant association between abnormal MRI and clinically active disease (P = 0.012). US elastography was abnormal in 4 of 10 cases with abnormal MRI and in 4 of 11 cases with normal MRI. There was no association between abnormal elastography and either MRI (P > 0.999) or clinically active disease (P > 0.999). Muscle echogenicity was normal in 11 patients; all 11 had normal elastography. Of the ten patients with increased muscle echogenicity, eight had abnormal elastography. There was a significant association between muscle echogenicity and US elastography (P < 0.001). The positive and negative predictive values for elastography in the determination of active myositis were 75% and 31

  20. Shear-wave elastography of the liver and spleen identifies clinically significant portal hypertension: A prospective multicentre study.

    Science.gov (United States)

    Jansen, Christian; Bogs, Christopher; Verlinden, Wim; Thiele, Maja; Möller, Philipp; Görtzen, Jan; Lehmann, Jennifer; Vanwolleghem, Thomas; Vonghia, Luisa; Praktiknjo, Michael; Chang, Johannes; Krag, Aleksander; Strassburg, Christian P; Francque, Sven; Trebicka, Jonel

    2017-03-01

    Clinically significant portal hypertension (CSPH) is associated with severe complications and decompensation of cirrhosis. Liver stiffness measured either by transient elastography (TE) or Shear-wave elastography (SWE) and spleen stiffness by TE might be helpful in the diagnosis of CSPH. We recently showed the algorithm to rule-out CSPH using sequential liver- (L-SWE) and spleen-Shear-wave elastography (S-SWE). This study investigated the diagnostic value of S-SWE for diagnosis of CSPH. One hundred and fifty-eight cirrhotic patients with pressure gradient measurements were included into this prospective multicentre study. L-SWE was measured in 155 patients, S-SWE in 112 patients, and both in 109 patients. Liver-shear-wave elastography and S-SWE correlated with clinical events and decompensation. SWE of liver and spleen revealed strong correlations with the pressure gradient and to differentiate between patients with and without CSPH. The best cut-off values were 24.6 kPa:L-SWE and 26.3 kPa:S-SWE. L-SWE ≤16.0 kPa and S-SWE ≤21.7 kPa were able to rule-out CSPH. Cut-off values of L-SWE >29.5 kPa and S-SWE >35.6 kPa were able to rule-in CSPH (specificity >92%). Patients with a L-SWE >38.0 kPa had likely CSPH. In patients with L-SWE ≤38.0 kPa, a S-SWE >27.9 kPa ruled in CSPH. This algorithm has a sensitivity of 89.2% and a specificity of 91.4% to rule-in CSPH. Patients not fulfilling these criteria may undergo HVPG measurement. Liver and spleen SWE correlate with portal pressure and can both be used as a non-invasive method to investigate CSPH. Even though external validation is still missing, these algorithms to rule-out and rule-in CSPH using sequential SWE of liver and spleen might change the clinical practice. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Genetics in chronic venous disease.

    Science.gov (United States)

    Grant, Yasmin; Onida, Sarah; Davies, Alun

    2017-02-01

    Chronic venous disease is highly prevalent in the Western world, with varicose veins being the most common form of clinical manifestation. With recent developments in sequencing technology, clinicians and geneticists alike are embarking on a journey to identify and unravel the genetic candidates of chronic venous disease. There is now currently substantial evidence to suggest the presence of genetic influences in the aetiology and pathology of venous disease. Despite this, the precise nature and profile of the genes involved in chronic venous disease remain a poorly understood entity. Moreover, it is strikingly apparent that the majority of venous genetic studies conducted over the past decade do not adhere to fundamental research principles. The emergence of high-throughput genotyping platforms permits a more systematic search for inherited components of venous disease. Pursuing a genome-wide frontier has the potential to reveal novel critical metabolic pathways and explain the genetic susceptibility of chronic venous disease. An expedited knowledge of the genetic factors in the aetiology of venous disease may translate into better prevention or treatment, which would benefit patients suffering from its clinical sequelae. Researchers should be urged to foster collaborative links and design a genome-wide case-control association study as an international consortium to provide a statistically robust paradigm in the field of chronic venous disease genetics. This will carry promise for clinically relevant progress and represent a first step towards better understanding of the genetics of chronic venous disease aetiology.

  2. Performance of real-time elastography for the staging of hepatic fibrosis: a meta-analysis.

    Directory of Open Access Journals (Sweden)

    Huisuo Hong

    Full Text Available BACKGROUND: With the rapid development of real-time elastography (RTE, a variety of measuring methods have been developed for the assessment of hepatic fibrosis. We evaluated the overall performance of four methods based on RTE by performing meta-analysis of published literature. METHODS: Online journal databases and a manual search from April 2000 to April 2014 were used. Studies from different databases that meet inclusion criteria were enrolled. The statistical analysis was performed using a random-effects model and fixed-effects model for the overall effectiveness of RTE. The area under the receiver operating characteristic curve (AUROC was calculated for various means. Fagan plot analysis was used to estimate the clinical utility of RTE, and the heterogeneity of the studies was explored with meta-regression analysis. RESULTS: Thirteen studies from published articles were enrolled and analyzed. The combined AUROC of the liver fibrosis index (LFI for the evaluation of significant fibrosis (F≥2, advanced fibrosis (F≥3, and cirrhosis (F = 4 were 0.79, 0.94, and 0.85, respectively. The AUROC of the elasticity index (EI ranged from 0.75 to 0.92 for F≥2 and 0.66 to 0.85 for F = 4. The overall AUROC of the elastic ratio of the liver for the intrahepatic venous vessels were 0.94, 0.93, and 0.96, respectively. The AUROC of the elastic ratio of the liver for the intercostal muscle in diagnosing advanced fibrosis and cirrhosis were 0.96 and 0.92, respectively. There was significant heterogeneity in the diagnostic odds ratio (DOR for F≥2 of LFI mainly due to etiology (p<0.01. CONCLUSION: The elastic ratio of the liver for the intrahepatic vein has excellent precision in differentiating each stage of hepatic fibrosis and is recommend to be applied to the clinic.

  3. Understanding Guyton's venous return curves

    National Research Council Canada - National Science Library

    Beard, Daniel A; Feigl, Eric O

    2011-01-01

    ...) was experimentally increased the right atrial pressure decreased, Arthur Guyton and coworkers proposed an interpretation that right atrial pressure represents a back pressure restricting venous return...

  4. Evaluation of ocular and periocular elasticity after panretinal photocoagulation: an ultrasonic elastography study.

    Science.gov (United States)

    Pekel, Gökhan; Ağladıoğlu, Kadir; Acer, Semra; Yağcı, Ramazan; Kaşıkçı, Alper

    2015-03-01

    Our aim was to evaluate the effects of argon laser panretinal photocoagulation on ocular and periocular ultrasound elastography values in diabetic retinopathy. Also, we wanted to test the applicability of ultrasound elastography in ophthalmological practice. This is a prospective cross-sectional study comparing proliferative diabetic retinopathy patients (study group) who had undergone panretinal photocoagulation and non-proliferative diabetic retinopathy patients (control group). There were 15 participants (11 males and 4 females) in the study group and 16 participants (10 males and 6 females) in the control group. The ultrasound elastography measurements were done with the LOGİQ E9 Ultrasound Elastography. The elastography values of vitreous, retrobulbar fat, and optic nerve were similar in both groups (p > 0.05). But, the mean retina-choroid-scleral elastography value of the study group was higher than that of the control group, which indicates increased hardness (p = 0.002). The argon laser panretinal photocoagulation decreases elasticity of the retina-choroid-sclera complex. The ultrasound elastography technique, that gives reproducible and consistent values, could be used effectively in ophthalmological practice.

  5. The usefulness of transient elastography, acoustic-radiation-force impulse elastography, and real-time elastography for the evaluation of liver fibrosis

    Directory of Open Access Journals (Sweden)

    Jong Ho Chung

    2013-06-01

    Full Text Available Background/AimsSeveral noninvasive methods have recently been developed for the evaluation of liver fibrosis. The accuracy of transient elastography (TE, acoustic-radiation-force impulse (ARFI elastography, and real-time elastography (RTE in predicting liver fibrosis were evaluated.MethodsSeventy-four patients who had undergone a liver biopsy within the previous 6 months were submitted to evaluation with TE, ARFI, and RTE on the same day.ResultsThere were significant correlations between fibrosis stage and liver stiffness measurement (LSM using the three tested methods: TE, r2=0.272, P=0.0002; ARFI, r2=0.225, P=0.0017; and RTE, r2=0.228, P=0.0015. The areas under the receiver operating characteristic curves (AUROC for the diagnosis of significant fibrosis (≥F2, Metavir stage by TE, ARFI, RTE, TE/platelet count (PLT, velocity of shear wave (Vs/PLT, and elasticity score (Es/PLT were 0.727, 0.715, 0.507, 0.876, 0.874, and 0.811, respectively. The AUROC for the diagnosis of cirrhosis by TE, ARFI, RTE, TE/PLT, Vs/PLT, and Es/PLT were 0.786, 0.807, 0.767, 0.836, 0.819, and 0.838, respectively. Comparisons of AUROC between all LSMs for predicting significant fibrosis (≥F2 produced the following results: TE vs. RTE, P=0.0069; ARFI vs. RTE, P=0.0277; and TE vs. ARFI, P=0.8836. Applying PLT, the ability of each LSM to predict fibrosis stage significantly increased: TE/PLT vs. TE, P=0.0004; Vs/PLT vs. ARFI, P=0.0022; and Es/PLT vs. RTE, P<0.0001. However, the ability to predict cirrhosis was not enhanced, combining LSM and PLT.ConclusionsTE and ARFI may be better methods for predicting significant liver fibrosis than RTE. This predictive ability increased significantly when accounting for platelet count. However, all of the measures had comparable efficacies for predicting cirrhosis.

  6. In vivo skin elastography with high-definition optical videos.

    Science.gov (United States)

    Zhang, Yong; Brodell, Robert T; Mostow, Eliot N; Vinyard, Christopher J; Marie, Hazel

    2009-08-01

    Continuous measurements of biomechanical properties of skin provide potentially valuable information to dermatologists for both clinical diagnosis and quantitative assessment of therapy. This paper presents an experimental study on in vivo imaging of skin elastic properties using high-definition optical videos. The objective is to (i) investigate whether skin property abnormalities can be detected in the computed strain elastograms, (ii) quantify property abnormalities with a Relative Strain Index (RSI), so that an objective rating system can be established, (iii) determine whether certain skin diseases are more amenable to optical elastography and (iv) identify factors that may have an adverse impact on the quality of strain elastograms. There are three steps in optical skin elastography: (i) skin deformations are recorded in a video sequence using a high-definition camcorder, (ii) a dense motion field between two adjacent video frames is obtained using a robust optical flow algorithm, with which a cumulative motion field between two frames of a larger interval is derived and (iii) a strain elastogram is computed by applying two weighted gradient filters to the cumulative motion data. Experiments were carried out using videos of 25 patients. In the three cases presented in this article (hypertrophic lichen planus, seborrheic keratosis and psoriasis vulgaris), abnormal tissues associated with the skin diseases were successfully identified in the elastograms. There exists a good correspondence between the shape of property abnormalities and the area of diseased skin. The computed RSI gives a quantitative measure of the magnitude of property abnormalities that is consistent with the skin stiffness observed on clinical examinations. Optical elastography is a promising imaging modality that is capable of capturing disease-induced property changes. Its main advantage is that an elastogram presents a continuous description of the spatial variation of skin properties on

  7. Histoscanning and shear wave ultrasound elastography for prostate cancer diagnosis

    Directory of Open Access Journals (Sweden)

    A. V. Amosov

    2016-01-01

    Full Text Available Introduction. The shear wave ultrasound elastography is a recently developed ultrasound-based method in the clinical practice, which allows the qualitative visual and quantitative measurements of tissue stiffness. In the 2010 this technology of the shear wave was called Shear Wave Elastograhpy. Due to the front of the shear waves the qualitative and quantitative assessment of the tissue stiffness is possible.Objective is to examine the efficacy of the shear wave ultrasound elastography in the evaluation of the prevalence of the oncological disease in patients with the prostate cancer and to compare the obtained results with the routine method X-ray diagnostics.Materials and methods. From the april 2015 in the I.M. Sechenov First Moscow State Medical University Urology Clinic there were conducted 314 shear wave ultrasound elastography examinations of the prostate. The ultrasound system Aixplorer® by SuperSonic Imagine was used. This system provides information provided by B-mode and shear wave ultrasound elastography mode. The transrectal echograms were made in 6 dimensions, so called Q-boxes (3 demensions in the every lobe on the segments from the base to the apex, according to the biopsy zone. The unit of measurement was the mean value in the kilopaskals (kPa. All the patients were randomized into 3 groups. There were 146 men with the possible prostate cancer in the first group (prospective study, 120 men with the certain diagnosis of the prostate cancer in the second group (retrospective study and 48 healthy men in the third group (control study. In all the patients of the first and the second groups the routine complete examination, including the prostate specific antigen (PSA level examination, digital rectal examination (DRE, doppler transrectal ultrasonography (TRUS, histoscanning and ultrasound shear wave elastography (SWE, was conducted. In the 229 patients of the first and the second groups the prostatectomy with the

  8. Magnetic resonance elastography of the liver; Magnetresonanzelastographie der Leber

    Energy Technology Data Exchange (ETDEWEB)

    Sack, I.; Fischer, T.; Thomas, A. [Charite-Universitaetsmedizin Berlin, Campus Charite Mitte, Institut fuer Radiologie, Berlin (Germany); Braun, J. [Charite-Universitaetsmedizin Berlin, Campus Benjamin Franklin, Institut fuer Medizinische Informatik, Berlin (Germany)

    2012-08-15

    The early detection of liver fibrosis remains a major challenge in medical imaging. Nowadays staging of liver fibrosis is not a task for radiological examinations and the gold standard is liver puncture. Elastography is sensitive to the mechanical properties of soft tissues and in the liver stiffness is highly correlated to the degree of fibrosis. In magnetic resonance imaging elastography (MRE) time-harmonic vibrations are induced in the liver and encoded by motion-sensitive phase-contrast sequences. Viscoelastic constants are recovered from the obtained wave images and displayed by so-called elastograms. The MRE procedure is able to discriminate low grades of fibrosis (F0-F1) from medium and severe fibrosis (F2-F4) with a diagnostic accuracy (AUROC) of 0.92. Currently, MRE is the most sensitive imaging modality for the noninvasive staging of liver fibrosis. Current technical developments of MRE may further improve the accuracy of the method towards a new gold standard for noninvasive staging of fibrosis by radiologists. (orig.) [German] Die Leberfibrose laesst sich nichtinvasiv und bildgestuetzt nur schwer von normal gesundem Gewebe unterscheiden. Morphologische Kenngroessen geben kaum Aufschluss ueber das Vorliegen einer Leberfibrose, insbesondere der Schweregrad der Erkrankung kann nicht sicher beurteilt werden. Diagnose und Graduierung der Leberfibrose sind derzeit keine Aufgabenstellungen der Radiologie, als Goldstandard gilt die Leberpunktion. Die Elastographie ist sensitiv auf Veraenderungen mechanischer Eigenschaften eines Organs. In der Leber korreliert der Fibrosegrad mit der Steifigkeit. Die Elastographie in der MRT (MRE) nutzt harmonische Schwingungen, welche ueber bewegungssensitive Phasenkontrastaufnahmetechniken kodiert werden. Aus den aufgenommenen Wellenbildern koennen Karten viskoelastischer Kenngroessen berechnet werden. Auf dem derzeitigen Stand der Technik ist die MRE in der Lage, fruehe Fibrosegrade (F0-F1) von mittlerer und schwerer Fibrose

  9. New Mathematical Data Analysis for Magnetic Resonance Elastography

    OpenAIRE

    吉川, 功剛

    2013-01-01

    For the diagnosing modality called MRE (Magnetic Resonance Elastogra-phy), the displacement vector of a wave propagating in a human tissue can bemeasured. The average of the local wave length of the wave from this mea-sured data could be an index for the diagnosing, because the local wave lengthbecomes larger when the tissue is stiffer. By assuming that the local form ofthe wave is given approximately as multiple complex plane waves, we identifythe real part of the complex linear phase of the...

  10. Update on ultrasound elastography: Miscellanea. Prostate, testicle, musculo-skeletal

    Energy Technology Data Exchange (ETDEWEB)

    Correas, J.M. [Descartes University and Necker University Hospital, Department of Adult Radiology, Paris (France); Drakonakis, E. [Nuffield Orthopaedic Centre, Oxford (United Kingdom); Isidori, A.M. [Sapienza University of Rome, Department of Experimental Medicine, Rome (Italy); Hélénon, O. [Descartes University and Necker University Hospital, Department of Adult Radiology, Paris (France); Pozza, C. [Sapienza University of Rome, Department of Experimental Medicine, Rome (Italy); Cantisani, V., E-mail: vito.cantisani@uniroma1.it [Sapienza University of Rome, Department of Radiology, Rome (Italy); Di Leo, N.; Maghella, F.; Rubini, A.; Drudi, F.M.; D’ambrosio, F. [Sapienza University of Rome, Department of Radiology, Rome (Italy)

    2013-11-01

    Nowadays ultrasound elastosonography is an established technique, although with limited clinical application, used to assess tissue stiffness, which is a parameter that in most cases is associated with malignancy. However, although a consistent number of articles have been published about several applications of elastosonography, its use in certain human body districts is still not well defined. In this paper we write on the use of elastosonography in prostate, testicle and musculo-skeletal apparatus. We report and compare the work of several authors, different type of elastosonography (shear wave, strain elastography, etc.) and instrumental data obtained in the study of both benign and malignant lesions.

  11. Venous function after pharmacomechanical thrombolysis for ...

    African Journals Online (AJOL)

    Background: Chronic venous insufficiency is an important complication following iliofemoral deep venous thrombosis. Early thrombus removal may preserve venous function and prevent this complication. This study represents the largest reported South African series of pharmacomechanical thrombolysis for iliofemoral ...

  12. Value of ultrasound elastography in the diagnosis of native kidney fibrosis.

    Science.gov (United States)

    Peride, Ileana; Rădulescu, Daniela; Niculae, Andrei; Ene, Vladimir; Bratu, Ovidiu Gabriel; Checheriță, Ionel Alexandru

    2016-09-01

    In the last decade, ultrasound elastography, an already widely used technique in the diagnosis of hepatic fibrosis, has raised the attention of nephrologists as a potential valuable noninvasive tool for the diagnosis of renal fibrosis. Due to renal deep location and anatomic complexity, the shear wave techniques are the most appropriate elastography methods for exploring native kidneys. Recent research offers promising results, but further larger studies are required for a better standardization of this method and also for establishing reference values of normal kidney elasticity. This article reviews the studies conducted for exploring the native kidney, highlighting the advantages and limitations of ultrasound elastography for assessing fibrosis development in chronic kidney diseases.

  13. Musculoskeletal applications of elastography: a pictorial essay of our initial experience.

    Science.gov (United States)

    Lalitha, Palle; Reddy, M Ch Balaji; Reddy, K Jagannath

    2011-01-01

    Elastography is an ultrasound-based newer imaging technique that is currently being used for the evaluation of breast lesions and hepatic pathology. It is also being evaluated for characterizing lesions of the prostate, thyroid, cervix and lymph nodes. We have applied real-time sonoelastography to a variety of musculoskeletal pathologies and here we report the findings of elastography for the evaluation of various musculoskeletal pathologies. Elastography of musculoskeletal lesions is not yet being routinely used in clinical practice, but it is being extensively researched.

  14. Musculoskeletal Applications of Elastography: a Pictorial Essay of Our Initial Experience

    Energy Technology Data Exchange (ETDEWEB)

    Lalitha, Palle; Reddy, Balaji; Reddy, K. Jagannath [Focus Diagnostic Center, Punjagutta (India)

    2011-06-15

    Elastography is an ultrasound-based newer imaging technique that is currently being used for the evaluation of breast lesions and hepatic pathology. It is also being evaluated for characterizing lesions of the prostate, thyroid, cervix and lymph nodes. We have applied real-time sonoelastography to a variety of musculoskeletal pathologies and here we report the findings of elastography for the evaluation of various musculoskeletal pathologies. Elastography of musculoskeletal lesions is not yet being routinely used in clinical practice, but it is being extensively researched.

  15. The clinical importance of air plethysmography in the assessment of chronic venous disease

    Directory of Open Access Journals (Sweden)

    Nei Rodrigues Alves Dezotti

    Full Text Available Abstract Air plethysmography is a non-invasive test that can quantify venous reflux and obstruction by measuring volume changes in the leg. Its findings correlate with clinical and hemodynamic measures. It can quantitatively assess several components of venous hemodynamics: valvular reflux, calf muscle pump function, and venous obstruction. Although clinical uses of air plethysmography have been validated, it is used almost exclusively for medical research. Air plethysmography can be used to assess chronic venous disease, to evaluate improvement after venous surgery, to diagnose acute and past episodes of deep venous thrombosis, to evaluate compression stocking therapy, to study the physiological implications of high-heeled shoes in healthy women, and even to evaluate the probability of ulcer healing.

  16. Central venous catheter - dressing change

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000156.htm Central venous catheter - dressing change To use the sharing features on this page, please enable JavaScript. You have a central venous catheter. This is a tube that goes into a ...

  17. Chronic Venous Disease under pressure

    NARCIS (Netherlands)

    S.W.I. Reeder (Suzan)

    2013-01-01

    textabstractIn chapter 1 we provide a general introduction of this thesis. Chronic venous disease (CVD) is a common medical condition that affects 2-64% of the worldwide population and leads to leg ulcers in 1% of the Western population. Venous leg ulceration (VLU) has an unfavorable prognosis with

  18. Venous Thromboembolism in Adolescents

    Directory of Open Access Journals (Sweden)

    Aneta Samková

    2012-01-01

    Full Text Available The incidence of venous thromboembolism (VTE during childhood is low with two peaks – neonatal and adolescent age. This retrospective study is focused on clinical characteristics of VTE during adolescence. The main goals are to assess the most frequent inherited and acquired risk factors and to evaluate the benefit of D-dimers in diagnostics of venous thromboemblism. The data of 18 adolescents were analysed – 16 girls (88.9%, 2 boys (11.1%. In 9 patients (50% thrombosis of the lower limb deep veins was diagnosed, six patients (33.3% suffered from symptomatic pulmonary embolism (PE and 3 patients (16.7% from thrombosis at unusual sites. One patient had an idiopathic VTE, the mean number of the inherited and acquired risk factors was 2.6. The most frequent inherited risk factor was Leiden mutation of factor V (27.8%. The most frequent acquired risk factor was oral contraception (OC in 12 out of 16 girls (75%. All of our patients on oral contraception had one or more additional risk factors. 10 out of 18 (55.6% patients with VTE had elevated activity of factor VIII. The sensitivity of D-dimers was low (50% in patients with distal lower limb thrombosis, but very high (100% in patients with PE.

  19. Imaging mechanical properties of hepatic tissue by magnetic resonance elastography

    Science.gov (United States)

    Yin, Meng; Rouviere, Olivier; Burgart, Lawrence J.; Fidler, Jeff L.; Manduca, Armando; Ehman, Richard L.

    2006-03-01

    PURPOSE: To assess the feasibility of a modified phase-contrast MRI technique (MR Elastography) for quantitatively assessing the mechanical properties of hepatic tissues by imaging propagating acoustic shear waves. MATERIALS AND METHODS: Both phantom and human studies were performed to develop and optimize a practical imaging protocol by visualizing and investigating the diffraction field of shear waves generated from pneumatic longitudinal drivers. The effects of interposed ribs in a transcostal approach were also investigated. A gradient echo MRE pulse sequence was adapted for shear wave imaging in the liver during suspended respiration, and then tested to measure hepatic shear stiffness in 13 healthy volunteers and 1 patient with chronic liver disease to determine the potential of non-invasively detecting liver fibrosis. RESULTS: Phantom studies demonstrate that longitudinal waves generated by the driver are mode-converted to shear waves in a distribution governed by diffraction principles. The transcostal approach was determined to be the most effective method for generating shear waves in human studies. Hepatic stiffness measurements in the 13 normal volunteers demonstrated a mean value of 2.0+/-0.2kPa. The shear stiffness measurement in the patient was much higher at 8.5kPa. CONCLUSION: MR Elastography of the liver shows promise as a method to non-invasively detect and characterize diffuse liver disease, potentially reducing the need for biopsy to diagnose hepatic fibrosis.

  20. Computer-Aided tumor diagnosis in 3-D breast elastography.

    Science.gov (United States)

    Huang, Yao-Sian; Takada, Etsuo; Konno, Sachiyo; Huang, Chiun-Shen; Kuo, Ming-Hao; Chang, Ruey-Feng

    2018-01-01

    Breast cancer is the major cause of cancer-related mortality in women. However, the death rate can be effectively decreased if the breast cancer can be detected early and treated appropriately. In recent years, many studies have indicated that the elastography has the better diagnosis performance than conventional ultrasound (US). In this study, the 3-D tumor contour is obtained by using the proposed segmentation methods and then the features containing texture information, shape information, ellipsoid fitting information are extracted respectively by using the segmented 3-D tumor contour and B-mode images, and the features containing elasticity information are calculated using the same contour and elastographic images. In this experiment, totally 40 biopsy-proved lesions containing 20 benign tumors and 20 malignant tumors are used to evaluate the proposed computer-aided diagnosis (CAD) system. From the experimental results, the combination of shape, ellipsoid fitting and elastographic features has the best performance with accuracy 90.50% (36/40), sensitivity 85.00% (17/20), specificity 95.00% (19/20), and the area under the ROC curve Az 0.987. The result shows that tumors can be diagnosed more precisely by using the elastography images. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Outreach screening of drug users for cirrhosis with transient elastography

    DEFF Research Database (Denmark)

    Moessner, Belinda K; Jørgensen, Tina R; Skamling, Merete

    2011-01-01

    Aims  Transient elastography (TE) is a non-invasive sensitive tool for diagnosing cirrhosis in hospital-based cohorts. This study aimed to evaluate TE as a screening tool for cirrhosis among drug users. Design  Cross-sectional study. Setting  All treatment centres in the county of Funen, Denmark....... Participants  Drug users attending treatment centres during the presence of the study team. Measurements  Liver stiffness measurements (LSM) by transient elastography using the Fibroscan device; blood tests for viral hepatitis, HIV infection and hyaluronic acid (HA) levels; and routine liver tests. Individuals...... with LSM ≥ 8 kPa were referred to the hospital for treatment evaluation. Individuals with LSM ≥ 12 kPa were recommended a liver biopsy. Findings  Among 175 drug users negative for hepatitis C, 13% had LSM = 8-11.9 kPa and 4% had LSM ≥ 12 kPa; elevated LSM was associated with a body mass index (BMI) > 30...

  2. Influence of catheter position on estimated strain in intravascular elastography.

    Science.gov (United States)

    De Korte, C L; Cespedes, E I; Van Der Steen, A W

    1999-01-01

    In elastography, an erroneous strain estimate is obtained when the radial strain and the probing ultrasound beam are not properly aligned: the "strain projection artifact". In practice, an angle between the strain and the ultrasound beam will be present in most of the cases due to inhomogeneities or nonuniform compression. In this study, a theoretical function describing the strain projection artifact is derived as a function of the angle between the radial strain and the ultrasound beam. Two main factors for an angle between strain and ultrasound beam in intravascular elastographic experiments are eccentricity and tilt of the transducer. The theoretical functions describing these errors are corroborated with strain estimates from an experiment with a circular, homogeneous gel-based vessel phantom. Comparison between the theoretical functions and the experimental results reveals that the strain projection artifact is well described by the theoretical findings. As a result, the experimental data can be corrected for this artifact. The corrected elastograms reveal that correct strain estimates are obtained when the eccentricity of the intravascular catheter is less than 63%. An "off-the-wall" device may be required to advance intravascular elastography to in vivo implementation.

  3. Shear wave elastography using phase sensitive optical coherence tomography

    Science.gov (United States)

    Song, Shaozhen; Huang, Zhihong; Nguyen, Thu-Mai; Wong, Emily Y.; Arnal, Bastien; O'Donnell, Matthew; Wang, Ruikang K.

    2014-03-01

    Optical coherence tomography (OCT) provides high spatial resolution and sensitivity that are ideal for imaging the cornea and lens. Quantifying the biomechanical properties of these tissues could add clinically valuable information. Thus, we propose a dynamic elastography method combining OCT detection and a mechanical actuator to map the shear modulus of soft tissues. We used a piezoelectric actuator driven in the kHz range and we used phase-sensitive OCT (PhS-OCT) to track the resulting shear waves at an equivalent frame rate of 47 kHz. We mapped the shear wave speed of anesthetized mice cornea using monochromatic excitations. We found a significant difference between a group of knock-out (3.92 +/- 0.35 m/s, N=4) and wild-type mice (5.04 +/- 0.51 m/s, N=3). These preliminary results demonstrate the feasibility of using PhS-OCT to perform in vivo shear wave elastography of the cornea. We then implemented a shear pulse compression approach on ex vivo human cornea. For that purpose, frequency- modulated excitations were used and the resulting displacement field was digitally compressed in a short broadband pulse with a 7 dB gain in signal-to-noise ratio (SNR).

  4. Diagnostic Performance of MR Elastography and Vibration-controlled Transient Elastography in the Detection of Hepatic Fibrosis in Patients with Severe to Morbid Obesity.

    Science.gov (United States)

    Chen, Jun; Yin, Meng; Talwalkar, Jayant A; Oudry, Jennifer; Glaser, Kevin J; Smyrk, Thomas C; Miette, Véronique; Sandrin, Laurent; Ehman, Richard L

    2017-05-01

    Purpose To evaluate the diagnostic performance and examination success rate of magnetic resonance (MR) elastography and vibration-controlled transient elastography (VCTE) in the detection of hepatic fibrosis in patients with severe to morbid obesity. Materials and Methods This prospective and HIPAA-compliant study was approved by the institutional review board. A total of 111 patients (71 women, 40 men) participated. Written informed consent was obtained from all patients. Patients underwent MR elastography with two readers and VCTE with three observers to acquire liver stiffness measurements for liver fibrosis assessment. The results were compared with those from liver biopsy. Each pathology specimen was evaluated by two hepatopathologists according to the METAVIR scoring system or Brunt classification when appropriate. All imaging observers were blinded to the biopsy results, and all hepatopathologists were blinded to the imaging results. Examination success rate, interobserver agreement, and diagnostic accuracy for fibrosis detection were assessed. Results In this obese patient population (mean body mass index = 40.3 kg/m2; 95% confidence interval [CI]: 38.7 kg/m2, 41.8 kg/m2]), the examination success rate was 95.8% (92 of 96 patients) for MR elastography and 81.3% (78 of 96 patients) or 88.5% (85 of 96 patients) for VCTE. Interobserver agreement was higher with MR elastography than with biopsy (intraclass correlation coefficient, 0.95 vs 0.89). In patients with successful MR elastography and VCTE examinations (excluding unreliable VCTE examinations), both MR elastography and VCTE had excellent diagnostic accuracy in the detection of clinically significant hepatic fibrosis (stage F2-F4) (mean area under the curve: 0.93 [95% CI: 0.85, 0.97] vs 0.91 [95% CI: 0.83, 0.96]; P = .551). Conclusion In this obese patient population, both MR elastography and VCTE had excellent diagnostic performance for assessing hepatic fibrosis; MR elastography was more technically

  5. Venous Thrombosis Risk after Cast Immobilization of the Lower Extremity: Derivation and Validation of a Clinical Prediction Score, L-TRiP(cast, in Three Population-Based Case-Control Studies.

    Directory of Open Access Journals (Sweden)

    Banne Nemeth

    2015-11-01

    Full Text Available Guidelines and clinical practice vary considerably with respect to thrombosis prophylaxis during plaster cast immobilization of the lower extremity. Identifying patients at high risk for the development of venous thromboembolism (VTE would provide a basis for considering individual thromboprophylaxis use and planning treatment studies. The aims of this study were (1 to investigate the predictive value of genetic and environmental risk factors, levels of coagulation factors, and other biomarkers for the occurrence of VTE after cast immobilization of the lower extremity and (2 to develop a clinical prediction tool for the prediction of VTE in plaster cast patients.We used data from a large population-based case-control study (MEGA study, 4,446 cases with VTE, 6,118 controls without designed to identify risk factors for a first VTE. Cases were recruited from six anticoagulation clinics in the Netherlands between 1999 and 2004; controls were their partners or individuals identified via random digit dialing. Identification of predictor variables to be included in the model was based on reported associations in the literature or on a relative risk (odds ratio > 1.2 and p ≤ 0.25 in the univariate analysis of all participants. Using multivariate logistic regression, a full prediction model was created. In addition to the full model (all variables, a restricted model (minimum number of predictors with a maximum predictive value and a clinical model (environmental risk factors only, no blood draw or assays required were created. To determine the discriminatory power in patients with cast immobilization (n = 230, the area under the curve (AUC was calculated by means of a receiver operating characteristic. Validation was performed in two other case-control studies of the etiology of VTE: (1 the THE-VTE study, a two-center, population-based case-control study (conducted in Leiden, the Netherlands, and Cambridge, United Kingdom with 784 cases and 523

  6. Venous Thrombosis Risk after Cast Immobilization of the Lower Extremity: Derivation and Validation of a Clinical Prediction Score, L-TRiP(cast), in Three Population-Based Case-Control Studies.

    Science.gov (United States)

    Nemeth, Banne; van Adrichem, Raymond A; van Hylckama Vlieg, Astrid; Bucciarelli, Paolo; Martinelli, Ida; Baglin, Trevor; Rosendaal, Frits R; le Cessie, Saskia; Cannegieter, Suzanne C

    2015-11-01

    Guidelines and clinical practice vary considerably with respect to thrombosis prophylaxis during plaster cast immobilization of the lower extremity. Identifying patients at high risk for the development of venous thromboembolism (VTE) would provide a basis for considering individual thromboprophylaxis use and planning treatment studies. The aims of this study were (1) to investigate the predictive value of genetic and environmental risk factors, levels of coagulation factors, and other biomarkers for the occurrence of VTE after cast immobilization of the lower extremity and (2) to develop a clinical prediction tool for the prediction of VTE in plaster cast patients. We used data from a large population-based case-control study (MEGA study, 4,446 cases with VTE, 6,118 controls without) designed to identify risk factors for a first VTE. Cases were recruited from six anticoagulation clinics in the Netherlands between 1999 and 2004; controls were their partners or individuals identified via random digit dialing. Identification of predictor variables to be included in the model was based on reported associations in the literature or on a relative risk (odds ratio) > 1.2 and p ≤ 0.25 in the univariate analysis of all participants. Using multivariate logistic regression, a full prediction model was created. In addition to the full model (all variables), a restricted model (minimum number of predictors with a maximum predictive value) and a clinical model (environmental risk factors only, no blood draw or assays required) were created. To determine the discriminatory power in patients with cast immobilization (n = 230), the area under the curve (AUC) was calculated by means of a receiver operating characteristic. Validation was performed in two other case-control studies of the etiology of VTE: (1) the THE-VTE study, a two-center, population-based case-control study (conducted in Leiden, the Netherlands, and Cambridge, United Kingdom) with 784 cases and 523 controls

  7. Characterization of plaque components with intravascular ultrasound elastography in human femoral and coronary arteries in vitro

    NARCIS (Netherlands)

    C.L. de Korte (Chris); G. Pasterkamp (Gerard); H.A. Woutman; N. Bom (Klaas); A.F.W. van der Steen (Ton)

    2000-01-01

    textabstractBACKGROUND: The composition of plaque is a major determinant of coronary-related clinical syndromes. Intravascular ultrasound (IVUS) elastography has proven to be a technique capable of reflecting the mechanical properties of phantom material and the femoral arterial

  8. Liver elastography: what it is, how it is done, and how it is interpreted.

    Science.gov (United States)

    Murad Gutiérrez, V; Romero Enciso, J A

    2017-12-13

    Liver elastography is a noninvasive method for diagnosing fibrosis that has been developed over the last decade in response to the limitations of liver biopsies, blood markers, and traditional imaging modalities. There are different methods of measuring tissue stiffness through ultrasound; thus far, shear wave elastography has proven superior for diagnosing clinically significant liver fibrosis, where early detection modifies the approach to treatment and improves prognosis. This article aims to provide a brief review of the different methods for performing elastography with ultrasound, focusing especially on shear wave elastography and on technical aspects for carrying out the procedure and key points for interpreting the findings. Copyright © 2017 SERAM. Publicado por Elsevier España, S.L.U. All rights reserved.

  9. Collecting optical coherence elastography depth profiles with a micromachined cantilever probe

    NARCIS (Netherlands)

    Chavan, D.C.; Mo, J.; de Groot, M.; Meijering, A.E.C.; de Boer, J.F.; Iannuzzi, D.

    2013-01-01

    We present an experimental setup that combines optical coherence elastography depth sensing with atomic force microscope indentation. The instrument relies on a miniaturized cantilever probe that compresses a sample with a small footprint force and simultaneously collects an optical coherence

  10. Elasticity reconstruction for ultrasound elastography using a radial compression: an inverse approach.

    Science.gov (United States)

    Luo, Jianwen; Ying, Kui; Bai, Jing

    2006-12-22

    To reduce the inherent mechanical artifacts in the strain images, many groups have investigated solutions to the inverse problem in elastography. However, in prostate elastography or intravascular elastography where the compression direction is radial, the inverse problem has not been studied thoroughly. In this paper, an iterative approach is proposed to reconstruct tissue elasticity for ultrasound elastography using a radial compression. The method is based upon the stress-strain relations in the polar coordinates. Computer simulations in an intravascular model are performed to illustrate the feasibility of this method in reducing the mechanical artifacts of the strain images. The reconstructed elasticity error and the contrast-transfer efficiency (CTE) as a function of the iteration number show that the inverse approach converges with a few iterations.

  11. Acoustic radiation force impulse induced strain elastography and point shear wave elastography for evaluation of thyroid nodules.

    Science.gov (United States)

    Huang, Xian; Guo, Le-Hang; Xu, Hui-Xiong; Gong, Xue-Hao; Liu, Bo-Ji; Xu, Jun-Mei; Zhang, Yi-Feng; Li, Xiao-Long; Li, Dan-Dan; Qu, Shen; Fang, Lin

    2015-01-01

    The aim of the study was to evaluate the diagnostic performance of acoustic radiation force impulse (ARFI) induced strain elastography (SE), point shear wave elastography (p-SWE), and their combined use in differentiating thyroid nodules. This retrospective study included 155 thyroid nodules (94 benign and 61 malignant) in 136 patients. Ultrasound, ARFI-induced SE and p-SWE were performed on each nodule. Receiver operating characteristic curve (ROC) analyses were performed to assess the diagnostic efficacy of ARFI-induced SE, p-SWE and their combined use to distinguish benign from malignant thyroid nodules with histological results used as the reference standard. The areas under the ROC for ARFI-induced SE, p-SWE, and their combined use were 0.828, 0.829, and 0.840, respectively (both P > 0.05). The specificity of ARFI-induced SE was higher than that of p-SWE as well as their combined use (both P 10 mm, there were no significant differences in sensitivity and NPV among the three methods in differentiating thyroid nodules (all P > 0.05). In conclusions, ARFI-induced SE and p-SWE are both valuable tools for detecting malignant thyroid nodules. The combined use of ARFI-induced SE and p-SWE improves the diagnostic sensitivity and NPV significantly whereas ARFI-induced SE alone achieves the highest specificity.

  12. Acoustic radiation force impulse (ARFI) elastography of testicular disorders in dogs: preliminary results

    OpenAIRE

    FELICIANO, M. A. R.; Maronezi,M.C.; Simões,A.P.R.; G.S. Maciel; Pavan, L; B. Gasser; Silva, P.; Uscategui,R.R.; CARVALHO, C.F.; J. C. Canola; Vicente, W. R. R.

    2016-01-01

    The aim of this study was to describe the use of acoustic radiation force impulse (ARFI) elastography in the evaluation of testicular disorders in dogs. Eighteen dogs with testicular disorders (thirty-six testicles) were assessed. Echotexture, size, contours and margins of testes were analysed by ultrasonography. Deformities and tissue stiffness (greyscale and homogenous or heterogeneous) were evaluated by qualitative elastography and shear velocity was determined quantitatively. Subsequent t...

  13. Reference Cap of Poly Vinyl Alcohol for Quantitative Elastography of the Human Uterine Cervix

    DEFF Research Database (Denmark)

    Leonhard, Anne Katrine; Sandager, Puk; Rasmussen, Christina Kjærgaard

    . Department of Obstetrics and Gynecology, Aarhus University Hospital, Aarhus N, Denmark. ABSTRACT BODY: Objectives: To develop a reference cap for the ultrasound probe that allows for quantitative elastography of the cervical uterine tissue with preservation of a good ultrasonic image. Further to perform...... cap of PVA constitutes a promising tool for quantitative elastography of the anterior cervical lip, with an ultrasonic image of good quality and ability to significantly distinguish between cervical mechanical properties....

  14. Effect of Calcifications on Breast Ultrasound Shear Wave Elastography: An Investigational Study

    OpenAIRE

    Adriana Gregory; Mohammad Mehrmohammadi; Max Denis; Mahdi Bayat; Stan, Daniela L.; Mostafa Fatemi; Azra Alizad

    2015-01-01

    Purpose To investigate the effects of macrocalcifications and clustered microcalcifications associated with benign breast masses on shear wave elastography (SWE). Methods SuperSonic Imagine (SSI) and comb-push ultrasound shear elastography (CUSE) were performed on three sets of phantoms to investigate how calcifications of different sizes and distributions influence measured elasticity. To demonstrate the effect in vivo, three female patients with benign breast masses associated with mammogra...

  15. Rheological assessment of a polymeric spherical structure using a three-dimensional shear wave scattering model in dynamic spectroscopy elastography.

    Science.gov (United States)

    Montagnon, Emmanuel; Hadj-Henni, Anis; Schmitt, Cédric; Cloutier, Guy

    2014-02-01

    With the purpose of assessing localized rheological behavior of pathological tissues using ultrasound dynamic elastography, an analytical shear wave scattering model was used in an inverse problem framework. The proposed method was adopted to estimate the complex shear modulus of viscoelastic spheres from 200 to 450 Hz. The inverse problem was formulated and solved in the frequency domain, allowing assessment of the complex viscoelastic shear modulus at discrete frequencies. A representative rheological model of the spherical obstacle was determined by comparing storage and loss modulus behaviors with Kelvin-Voigt, Maxwell, Zener, and Jeffrey models. The proposed inversion method was validated by using an external vibrating source and acoustic radiation force. The estimation of viscoelastic properties of three-dimensional spheres made softer or harder than surrounding tissues did not require a priori rheological assumptions. The proposed method is intended to be applied in the context of breast cancer imaging.

  16. Cerebral venous thrombosis.

    Science.gov (United States)

    Ferro, José Manuel; Canhão, Patrícia; Aguiar de Sousa, Diana

    2016-12-01

    Cerebral venous thrombosis (CVT) has an incidence of 1.32/100,000/years in high-income countries, and higher in middle- and low-income countries. CVT is more frequent in infants and children young adults and females, especially during pregnancy/puerperium. CVT are now being diagnosed with increasing frequency because of the increased awareness and higher use of magnetic resonance imaging (MR) for investigating patients with acute and subacute headaches and new onset seizures. CVT rarely present as a stroke syndrome. Their most frequent presentations are isolated headache, intracranial hypertension syndrome, seizures, a lobar syndrome and encephalopathy. The confirmation of the diagnosis of CVT relies on the demonstration of thrombi in the cerebral veins and/or sinuses by MR/MR venography or veno CT. The more frequent risk factors/associated conditions for CVT are genetic prothrombotic conditions, antiphospholipid syndrome and other acquired prothrombotic diseases, including cancer, oral contraceptives, puerperium and pregnancy, infections and trauma. The prognosis of CVT is in general favorable, as acute death rate is below 5% and only 15% of the patients remain dependent or die. Treatment in the acute phase includes management of the associated condition, anticoagulation with either low molecular weight or unfractionated heparin, treatment of intracranial hypertension, prevention of recurrent seizures and headache relief. In patients in severe condition on admission or who deteriorate despite anticoagulation, local thrombolysis or thrombectomy is an option. Decompressive surgery is lifesaving in patients with large venous infarcts or hemorrhage with impending herniation. After the acute phase, patients should anticoagulated for a variable period of time, depending on their inherent thrombotic risk. CVT patients may experience recurrent seizures. Prophylaxis with anti-epileptic drugs is recommended after the first seizure, in those with hemispheric lesions. There

  17. Venous chest anatomy: clinical implications.

    Science.gov (United States)

    Chasen, M H; Charnsangavej, C

    1998-03-01

    This article provides a practical approach to the clinical implications and importance of understanding the collateral venous anatomy of the thorax. Routine radiography, conventional venography, computed tomography (CT), and magnetic resonance (MR) imaging studies provide correlative anatomic models for the demonstration of how interconnecting collateral vascular networks within the thorax maintain venous stability at all times. Five major systems comprise the collateral venous network of the thorax (Fig. 1). These include the paravertebral, azygos-hemiazygos, internal mammary, lateral thoracic, and anterior jugular venous systems (AJVS). The five systems are presented in the following sequence: (a) a brief introduction to the importance of catheter position and malposition in understanding access to the thoracic venous system, (b) the anatomy of the azygos-hemiazygos systems and their relationship with the paravertebral plexus, (c) the importance of the AJVS, (d) 'loop' concepts interconnecting the internal mammary and azygos-hemiazygos systems by means of the lateral thoracic and intercostal veins, and (e) the interconnecting venous networks on the thoracic side of the thoracoabdominal junction. Certain aspects of the venous anatomy of the thorax will not be discussed in this chapter and include (a) the intra-abdominal anastomoses between the superior and inferior vena cavae (IVC) via the internal mammary, lateral thoracic, and azygos-hemiazygos systems (beyond the scope of this article), (b) potential collateral vessels involving vertebral, parascapular, thyroidal, thymic, and other smaller veins that might anastomose with the major systems, and (c) anatomic variants and pitfalls that may mimic pathologic conditions (space limitations).

  18. Principles and clinical application of ultrasound elastography for diffuse liver disease

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Woo Kyoung; Lim, Hyo K. [Dept. of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Lee, Hyoung Ki; Jo, Jae Moon [Health Medical Equipment Business, Samsung Electronics, Seoul (Korea, Republic of); Kim, Yong Soo [Dept. of Radiology, Hanyang University Guri Hospital, Hanyang University College of Medicine, Guri (Korea, Republic of)

    2014-10-15

    Accurate assessment of the degree of liver fibrosis is important for estimating prognosis and deciding on an appropriate course of treatment for cases of chronic liver disease (CLD) with various etiologies. Because of the inherent limitations of liver biopsy, there is a great need for non-invasive and reliable tests that accurately estimate the degree of liver fibrosis. Ultrasound (US) elastography is considered a non-invasive, convenient, and precise technique to grade the degree of liver fibrosis by measuring liver stiffness. There are several commercial types of US elastography currently in use, namely, transient elastography, acoustic radiation force impulse imaging, supersonic shear-wave imaging, and real-time tissue elastography. Although the low reproducibility of measurements derived from operator-dependent performance remains a significant limitation of US elastography, this technique is nevertheless useful for diagnosing hepatic fibrosis in patients with CLD. Likewise, US elastography may also be used as a convenient surveillance method that can be performed by physicians at the patients' bedside to enable the estimation of the prognosis of patients with fatal complications related to CLD in a non-invasive manner.

  19. Principles and clinical application of ultrasound elastography for diffuse liver disease

    Directory of Open Access Journals (Sweden)

    Woo Kyoung Jeong

    2014-07-01

    Full Text Available Accurate assessment of the degree of liver fibrosis is important for estimating prognosis and deciding on an appropriate course of treatment for cases of chronic liver disease (CLD with various etiologies. Because of the inherent limitations of liver biopsy, there is a great need for non-invasive and reliable tests that accurately estimate the degree of liver fibrosis. Ultrasound (US elastography is considered a non-invasive, convenient, and precise technique to grade the degree of liver fibrosis by measuring liver stiffness. There are several commercial types of US elastography currently in use, namely, transient elastography, acoustic radiation force impulse imaging, shear wave imaging, and real-time elastography. Although the low reproducibility of measurements derived from operator-dependent performance remains a significant limitation of US elastography, this technique is nevertheless useful for diagnosing hepatic fibrosis in patients with CLD. Likewise, US elastography may also be used as a convenient surveillance method that can be performed by physicians at the patients’ bedside to enable the estimation of the prognosis of patients with fatal complications related to CLD in a non-invasive manner.

  20. Supersonic transient magnetic resonance elastography for quantitative assessment of tissue elasticity

    Science.gov (United States)

    Liu, Yu; Liu, Jingfei; Fite, Brett Z.; Foiret, Josquin; Ilovitsh, Asaf; Leach, J. Kent; Dumont, Erik; Caskey, Charles F.; Ferrara, Katherine W.

    2017-05-01

    Non-invasive, quantitative methods to assess the properties of biological tissues are needed for many therapeutic and tissue engineering applications. Magnetic resonance elastography (MRE) has historically relied on external vibration to generate periodic shear waves. In order to focally assess a biomaterial or to monitor the response to ablative therapy, the interrogation of a specific region of interest by a focused beam is desirable and transient MRE (t-MRE) techniques have previously been developed to accomplish this goal. Also, strategies employing a series of discrete ultrasound pulses directed to increasing depths along a single line-of-sight have been designed to generate a quasi-planar shear wave. Such ‘supersonic’ excitations have been applied for ultrasound elasticity measurements. The resulting shear wave is higher in amplitude than that generated from a single excitation and the properties of the media are simply visualized and quantified due to the quasi-planar wave geometry and the opportunity to generate the wave at the site of interest. Here for the first time, we extend the application of supersonic methods by developing a protocol for supersonic transient magnetic resonance elastography (sst-MRE) using an MR-guided focused ultrasound system capable of therapeutic ablation. We apply the new protocol to quantify tissue elasticity in vitro using biologically-relevant inclusions and tissue-mimicking phantoms, compare the results with elasticity maps acquired with ultrasound shear wave elasticity imaging (US-SWEI), and validate both methods with mechanical testing. We found that a modified time-of-flight (TOF) method efficiently quantified shear modulus from sst-MRE data, and both the TOF and local inversion methods result in similar maps based on US-SWEI. With a three-pulse excitation, the proposed sst-MRE protocol was capable of visualizing quasi-planar shear waves propagating away from the excitation location and detecting differences in shear

  1. Supersonic transient magnetic resonance elastography for quantitative assessment of tissue elasticity.

    Science.gov (United States)

    Liu, Yu; Liu, Jingfei; Fite, Brett Z; Foiret, Josquin; Ilovitsh, Asaf; Leach, J Kent; Dumont, Erik; Caskey, Charles F; Ferrara, Katherine W

    2017-05-21

    Non-invasive, quantitative methods to assess the properties of biological tissues are needed for many therapeutic and tissue engineering applications. Magnetic resonance elastography (MRE) has historically relied on external vibration to generate periodic shear waves. In order to focally assess a biomaterial or to monitor the response to ablative therapy, the interrogation of a specific region of interest by a focused beam is desirable and transient MRE (t-MRE) techniques have previously been developed to accomplish this goal. Also, strategies employing a series of discrete ultrasound pulses directed to increasing depths along a single line-of-sight have been designed to generate a quasi-planar shear wave. Such 'supersonic' excitations have been applied for ultrasound elasticity measurements. The resulting shear wave is higher in amplitude than that generated from a single excitation and the properties of the media are simply visualized and quantified due to the quasi-planar wave geometry and the opportunity to generate the wave at the site of interest. Here for the first time, we extend the application of supersonic methods by developing a protocol for supersonic transient magnetic resonance elastography (sst-MRE) using an MR-guided focused ultrasound system capable of therapeutic ablation. We apply the new protocol to quantify tissue elasticity in vitro using biologically-relevant inclusions and tissue-mimicking phantoms, compare the results with elasticity maps acquired with ultrasound shear wave elasticity imaging (US-SWEI), and validate both methods with mechanical testing. We found that a modified time-of-flight (TOF) method efficiently quantified shear modulus from sst-MRE data, and both the TOF and local inversion methods result in similar maps based on US-SWEI. With a three-pulse excitation, the proposed sst-MRE protocol was capable of visualizing quasi-planar shear waves propagating away from the excitation location and detecting differences in shear

  2. Improvement of displacement estimation of breast tissue in ultrasound elastography using the monogenic signal.

    Science.gov (United States)

    Slimi, Taher; Moussa, Ines Marzouk; Kraiem, Tarek; Mahjoubi, Halima

    2017-01-17

    In breast ultrasound elastography, tissues displacements estimation is obtained through a technique that follows the evolution of tissues under stress. However, during the acquisition of B-mode images, tissue displacements are often contaminated with multiplicative noise caused by changes in the speckle pattern in the tissue. Thus, the application of monogenic signal technique on the B-mode image in order to estimate displacement tissue, result in a presence of amplified noise in the deformation tissue image, which severely obscures the useful information. In this paper, we propose a new method based on the monogenic features, that is to improve the old monogenic signal (OMS) technique by improving the filtering step, so that the use of an effective denoising technique is enough to ensure a good estimation of displacement tissue. Our proposed method is based on the use of a robust filtering technique combined with the monogenic model. Two models of phantom elasticity are used in our test validation sold by CIRS company. In-vivo testing was also performed on the sets of clinical B-mode images to 20 patients including malignant breast tumors. Shrinkage wavelets has been used to eliminate the noise according to the threshold, then a guided filter is introduced to completely filter the image, the monogenic model is used after excerpting the image feature and estimating analytically the displacement tissue. Accurate and excellent displacement estimation for breast tissue was observed in proposed method results. By adapting our proposed approach to breast B-mode images, we have shown that it demonstrated a higher performance for displacement estimation; it gives better values in term of standard deviation, higher contrast to noise ratio, greater peak signal-to-noise ratio, excellent structural similarity and much faster speed than OMS and B-spline techniques. The results of the proposed model are encouraging, allowing quick and reliable estimations. Although the proposed

  3. Quantified elasticity mapping of ocular tissue using acoustic radiation force optical coherence elastography (Conference Presentation)

    Science.gov (United States)

    Qu, Yueqiao; He, Youmin; Zhang, Yi; Ma, Teng; Zhu, Jiang; Miao, Yusi; Dai, Cuixia; Silverman, Ronald; Humayun, Mark S.; Zhou, Qifa; Chen, Zhongping

    2017-02-01

    Age-related macular degeneration and keratoconus are two ocular diseases occurring in the posterior and anterior eye, respectively. In both conditions, the mechanical elasticity of the respective tissues changes during the early onset of disease. It is necessary to detect these differences and treat the diseases in their early stages to provide proper treatment. Acoustic radiation force optical coherence elastography is a method of elasticity mapping using confocal ultrasound waves for excitation and Doppler optical coherence tomography for detection. We report on an ARF-OCE system that uses modulated compression wave based excitation signals, and detects the spatial and frequency responses of the tissue. First, all components of the system is synchronized and triggered such that the signal is consistent between frames. Next, phantom studies are performed to validate and calibrate the relationship between the resonance frequency and the Young's modulus. Then the frequency responses of the anterior and posterior eye are detected for porcine and rabbit eyes, and the results correlated to the elasticity. Finally, spatial elastograms are obtained for a porcine retina. Layer segmentation and analysis is performed and correlated to the histology of the retina, where five distinct layers are recognized. The elasticities of the tissue layers will be quantified according to the mean thickness and displacement response for the locations on the retina. This study is a stepping stone to future in-vivo animal studies, where the elastic modulus of the ocular tissue can be quantified and mapped out accordingly.

  4. Current role of transient elastography in the management of chronic hepatitis B patients

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Jung Hwan; Lee, Jung Il [Dept. of Internal Medicine, Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2017-04-15

    Liver fibrosis is an important prognostic factor for chronic hepatitis B (CHB), and accurate evaluation of the stage of liver fibrosis is crucial in establishing management strategies. While liver biopsy is still considered the gold standard for staging liver fibrosis or cirrhosis, transient elastography (TE), a noninvasive means of assessing liver fibrosis, has come to play an increasing role in this process. After extensive validation, TE is now regarded as a reliable surrogate maker for grading the severity of liver fibrosis in CHB patients. It can detect the extent of fibrosis in a patient and can also be used to evaluate longitudinal changes in liver fibrosis over time with or without interventional management, such as antiviral therapy. However, several confounders hinder the effective assessment of liver fibrosis using TE, such as extensive liver necroinflammation, hepatic congestion, and cholestasis. TE has limited use in obese patients or patients with ascites. Although TE has several limitations, due to its accessibility and safety, it is a valuable tool for the initial evaluation and follow-up in patients with CH.

  5. Current role of transient elastography in the management of chronic hepatitis B patients

    Directory of Open Access Journals (Sweden)

    Jung Hwan Yu

    2017-04-01

    Full Text Available Liver fibrosis is an important prognostic factor for chronic hepatitis B (CHB, and accurate evaluation of the stage of liver fibrosis is crucial in establishing management strategies. While liver biopsy is still considered the gold standard for staging liver fibrosis or cirrhosis, transient elastography (TE, a noninvasive means of assessing liver fibrosis, has come to play an increasing role in this process. After extensive validation, TE is now regarded as a reliable surrogate maker for grading the severity of liver fibrosis in CHB patients. It can detect the extent of fibrosis in a patient and can also be used to evaluate longitudinal changes in liver fibrosis over time with or without interventional management, such as antiviral therapy. However, several confounders hinder the effective assessment of liver fibrosis using TE, such as extensive liver necroinflammation, hepatic congestion, and cholestasis. TE has limited use in obese patients or patients with ascites. Although TE has several limitations, due to its accessibility and safety, it is a valuable tool for the initial evaluation and follow-up in patients with CHB.

  6. Clinical applications, limitations and future role of transient elastography in the management of liver disease.

    Science.gov (United States)

    Chang, Pik Eu; Goh, George Boon-Bee; Ngu, Jing Hieng; Tan, Hiang Keat; Tan, Chee Kiat

    2016-02-06

    Transient elastography (TE) is a reliable tool for the non-invasive assessment of liver fibrosis in routine clinical practice. TE is currently approved for use in Europe, Asia and the United States. The widespread adoption of this technology is certain to increase the use of TE worldwide. Although TE has been well validated in chronic viral hepatitis, its clinical role in other liver diseases remains less clear. The advent of new treatment for chronic hepatitis C and emerging prevalence of non-alcoholic steatohepatitis raises new questions on the role of TE in current clinical practice. This review aims to examine the clinical applications, limitations and future role of TE in current clinical practice in light of the changing epidemiology of liver diseases and new clinical management paradigms. In current clinical practice, TE is the most accurate non-invasive method for diagnosis of liver cirrhosis. TE is useful to rule out fibrosis and cirrhosis but does not have sufficient accuracy to discern between various stages of fibrosis. The clinical role of TE has evolved from cross-sectional point-in-time assessment of fibrosis and cirrhosis to the more relevant role of prediction of vital clinical end-points. This provides clinicians with the ability to modify treatment strategies based on the information provided by TE. TE has evolved over the past decade to become an essential tool to assist the clinician in the management of chronic liver disease.

  7. Assessing the accuracy and reproducibility of modality independent elastography in a murine model of breast cancer

    Science.gov (United States)

    Weis, Jared A.; Flint, Katelyn M.; Sanchez, Violeta; Yankeelov, Thomas E.; Miga, Michael I.

    2015-01-01

    Abstract. Cancer progression has been linked to mechanics. Therefore, there has been recent interest in developing noninvasive imaging tools for cancer assessment that are sensitive to changes in tissue mechanical properties. We have developed one such method, modality independent elastography (MIE), that estimates the relative elastic properties of tissue by fitting anatomical image volumes acquired before and after the application of compression to biomechanical models. The aim of this study was to assess the accuracy and reproducibility of the method using phantoms and a murine breast cancer model. Magnetic resonance imaging data were acquired, and the MIE method was used to estimate relative volumetric stiffness. Accuracy was assessed using phantom data by comparing to gold-standard mechanical testing of elasticity ratios. Validation error was elasticity imaging metric in a preclinical cancer model. Our results suggest that the MIE method can reproducibly generate accurate estimates of the relative mechanical stiffness and provide guidance on the degree of change needed in order to declare biological changes rather than experimental error in future therapeutic studies. PMID:26158120

  8. Quantifying tissue viscoelasticity using optical coherence elastography and the Rayleigh wave model

    Science.gov (United States)

    Han, Zhaolong; Singh, Manmohan; Aglyamov, Salavat R.; Liu, Chih-Hao; Nair, Achuth; Raghunathan, Raksha; Wu, Chen; Li, Jiasong; Larin, Kirill V.

    2016-09-01

    This study demonstrates the feasibility of using the Rayleigh wave model (RWM) in combination with optical coherence elastography (OCE) technique to assess the viscoelasticity of soft tissues. Dispersion curves calculated from the spectral decomposition of OCE-measured air-pulse induced elastic waves were used to quantify the viscoelasticity of samples using the RWM. Validation studies were first conducted on 10% gelatin phantoms with different concentrations of oil. The results showed that the oil increased the viscosity of the gelatin phantom samples. This method was then used to quantify the viscoelasticity of chicken liver. The Young's modulus of the chicken liver tissues was estimated as E=2.04±0.88 kPa with a shear viscosity η=1.20±0.13 Pa s. The analytical solution of the RWM correlated very well with the OCE-measured phased velocities (R2=0.96±0.04). The results show that the combination of the RWM and OCE is a promising method for noninvasively quantifying the biomechanical properties of soft tissues and may be a useful tool for detecting disease.

  9. Doppler ultrasound study and venous mapping in chronic venous insufficiency.

    Science.gov (United States)

    García Carriazo, M; Gómez de las Heras, C; Mármol Vázquez, P; Ramos Solís, M F

    2016-01-01

    Chronic venous insufficiency of the lower limbs is very prevalent. In recent decades, Doppler ultrasound has become the method of choice to study this condition, and it is considered essential when surgery is indicated. This article aims to establish a method for the examination, including venous mapping and preoperative marking. To this end, we review the venous anatomy of the lower limbs and the pathophysiology of chronic venous insufficiency and explain the basic hemodynamic concepts and the terminology required to elaborate a radiological report that will enable appropriate treatment planning and communication with other specialists. We briefly explain the CHIVA (the acronym for the French term "cure conservatrice et hémodynamique de l'insuffisance veineuse en ambulatoire"=conservative hemodynamic treatment for chronic venous insufficiency) strategy, a minimally invasive surgical strategy that aims to restore correct venous hemodynamics without resecting the saphenous vein. Copyright © 2015 SERAM. Published by Elsevier España, S.L.U. All rights reserved.

  10. Upper extremity deep venous thrombosis after port insertion: What are the risk factors?

    Science.gov (United States)

    Tabatabaie, Omidreza; Kasumova, Gyulnara G; Kent, Tara S; Eskander, Mariam F; Fadayomi, Ayotunde B; Ng, Sing Chau; Critchlow, Jonathan F; Tawa, Nicholas E; Tseng, Jennifer F

    2017-08-01

    Totally implantable venous access devices (ports) are widely used, especially for cancer chemotherapy. Although their use has been associated with upper extremity deep venous thrombosis, the risk factors of upper extremity deep venous thrombosis in patients with a port are not studied adequately. The Healthcare Cost and Utilization Project's Florida State Ambulatory Surgery and Services Database was queried between 2007 and 2011 for patients who underwent outpatient port insertion, identified by Current Procedural Terminology code. Patients were followed in the State Ambulatory Surgery and Services Database, State Inpatient Database, and State Emergency Department Database for upper extremity deep venous thrombosis occurrence. The cohort was divided into a test cohort and a validation cohort based on the year of port placement. A multivariable logistic regression model was developed to identify risk factors for upper extremity deep venous thrombosis in patients with a port. The model then was tested on the validation cohort. Of the 51,049 patients in the derivation cohort, 926 (1.81%) developed an upper extremity deep venous thrombosis. On multivariate analysis, independently significant predictors of upper extremity deep venous thrombosis included age deep venous thrombosis (odds ratio = 1.77), all-cause 30-day revisit (odds ratio = 2.36), African American race (versus white; odds ratio = 1.86), and other nonwhite races (odds ratio = 1.35). Additionally, compared with genitourinary malignancies, patients with gastrointestinal (odds ratio = 1.55), metastatic (odds ratio = 1.76), and lung cancers (odds ratio = 1.68) had greater risks of developing an upper extremity deep venous thrombosis. This study identified major risk factors of upper extremity deep venous thrombosis. Further studies are needed to evaluate the appropriateness of thromboprophylaxis in patients at greater risk of upper extremity deep venous thrombosis. Copyright © 2017 Elsevier Inc

  11. Central Venous Catheter (Central Line)

    Science.gov (United States)

    ... venous catheter (KATHeter), also known as a central line or CVC, is long, soft, thin, hollow tube ... into a large vein (blood vessel). A central line is much like an intravenous (IV) catheter that ...

  12. Clinical overview of venous thromboembolism

    African Journals Online (AJOL)

    circulation, causing either partial or complete obstruction of pulmonary blood flow (in 4–13% of ... Keywords:anticoagulants, deep vein thrombosis, DVT, embolus, NOAC, PE, pulmonary embolism, thromboprophylaxis, thrombus, venous thromboembolism ... Cigarette smoking, including passive smoking. Hypercoagulability ...

  13. Quantitative shear wave ultrasound elastography: initial experience in solid breast masses

    Science.gov (United States)

    2010-01-01

    Introduction Shear wave elastography is a new method of obtaining quantitative tissue elasticity data during breast ultrasound examinations. The aims of this study were (1) to determine the reproducibility of shear wave elastography (2) to correlate the elasticity values of a series of solid breast masses with histological findings and (3) to compare shear wave elastography with greyscale ultrasound for benign/malignant classification. Methods Using the Aixplorer® ultrasound system (SuperSonic Imagine, Aix en Provence, France), 53 solid breast lesions were identified in 52 consecutive patients. Two orthogonal elastography images were obtained of each lesion. Observers noted the mean elasticity values in regions of interest (ROI) placed over the stiffest areas on the two elastography images and a mean value was calculated for each lesion. A sub-set of 15 patients had two elastography images obtained by an additional operator. Reproducibility of observations was assessed between (1) two observers analysing the same pair of images and (2) findings from two pairs of images of the same lesion taken by two different operators. All lesions were subjected to percutaneous biopsy. Elastography measurements were correlated with histology results. After preliminary experience with 10 patients a mean elasticity cut off value of 50 kilopascals (kPa) was selected for benign/malignant differentiation. Greyscale images were classified according to the American College of Radiology (ACR) Breast Imaging Reporting and Data System (BI-RADS). BI-RADS categories 1-3 were taken as benign while BI-RADS categories 4 and 5 were classified as malignant. Results Twenty-three benign lesions and 30 cancers were diagnosed on histology. Measurement of mean elasticity yielded an intraclass correlation coefficient of 0.99 for two observers assessing the same pairs of elastography images. Analysis of images taken by two independent operators gave an intraclass correlation coefficient of 0.80. Shear

  14. Calidad de vida y cicatrización en pacientes con úlceras de etiología venosa: Validación del Charing Cross Venous Ulcer Questionnaire, versión española (CCVUQ-e y del Pressure Ulcer Scale for Healing, versión española (PUSH-e. Resultados preliminares Quality of life healing in patints with venous ulcers of etiology: Validation of Charing Cross Venous Ulcer Questionnaire, Spanish version (CCVUQ-e and the Pressure Ulcer Scale for Healing, Spanish version (PUSH-e. Preliminary results

    Directory of Open Access Journals (Sweden)

    Renata Virgina González-Consuegra

    2011-09-01

    correlación entre el CCVUQ-e y el PUSH-e al inicio fue r = 0,49 (p Introduction: in Spain, there is no specific measurement instruments for Health Related Quality of Life (HRQOL and to measuring progress towards healing in patients with chronic wounds that have been validated by research. Having these tools will help the decision-making and improve the quality of care to these patients. Thus, the objectives of this study are: to validate and establish the psychometric properties in Spanish, for "Charing Cross Venous Ulcer Questionnaire (CCVUQ-e" to measure HRQOL in patients with venous ulcers (UV and to validate and establish Clinical-metric properties, in Spanish, for "Pressure Ulcer Scale for Healing (PUSH-e" in the same sample. And, to establish what is the HRQOL of patients in the study sample. Methods: prospective validation of instruments, with a repeated measures model. A estimated sample of 105 patients were selected according to international standard for validating questionnaires. Procedure: for a period of 6 weeks, patients were studied every 2 weeks, collecting variables related to demography, status of disease, ulcers, HRQOL data through the questionnaire CCVUQ-e and SF-12 V2, treatments and healing data trough PUSH-e. Analysis: calculation of psychometric indicators and metrics for measuring clinical validity, reliability and sensitivity to change of such instruments. Descriptive statistics of the variables studied. Comparisons of outcome variables. Results: preliminary results of the study with data from 27 patients with UV. The sample contains all the characteristics of patients with UV. Preliminarily, the CCUVQ-e shows good internal consistency (Cronbach alpha > 0.80. The correlation between CCVUQ-e and PUSH-e at baseline was r = 0.49 (P < 0.001 and at the end of the study was r = 0.64 (p = 0.006. Sensitivity to change of instruments, as with repeated measures model, is statistically significant (p < 0.001. Conclusions: preliminary results show, in both

  15. Heritability of chronic venous disease

    OpenAIRE

    Fiebig, Andreas; Krusche, Petra; De Wolf, Andreas; Krawczak, Michael; Timm, Birgitt; Nikolaus, Susanna; Frings, Norbert; Schreiber, Stefan

    2010-01-01

    Varicose veins without skin changes have a prevalence of approximately 20% in Northern and Western Europe whereas advanced chronic venous insufficiency affects about 3% of the population. Genetic risk factors are thought to play an important role in the aetiology of both these chronic venous diseases (CVD). We evaluated the relative genetic and environmental impact upon CVD risk by estimating the heritability of the disease in 4,033 nuclear families, comprising 16,434 individuals from all ove...

  16. Neonatal Venous Thromboembolism

    Directory of Open Access Journals (Sweden)

    Kristina M. Haley

    2017-06-01

    Full Text Available Neonates are the pediatric population at highest risk for development of venous thromboembolism (VTE, and the incidence of VTE in the neonatal population is increasing. This is especially true in the critically ill population. Several large studies indicate that the incidence of neonatal VTE is up almost threefold in the last two decades. Central lines, fluid fluctuations, sepsis, liver dysfunction, and inflammation contribute to the risk profile for VTE development in ill neonates. In addition, the neonatal hemostatic system is different from that of older children and adults. Platelet function, pro- and anticoagulant proteins concentrations, and fibrinolytic pathway protein concentrations are developmentally regulated and generate a hemostatic homeostasis that is unique to the neonatal time period. The clinical picture of a critically ill neonate combined with the physiologically distinct neonatal hemostatic system easily fulfills the criteria for Virchow’s triad with venous stasis, hypercoagulability, and endothelial injury and puts the neonatal patient at risk for VTE development. The presentation of a VTE in a neonate is similar to that of older children or adults and is dependent upon location of the VTE. Ultrasound is the most common diagnostic tool employed in identifying neonatal VTE, but relatively small vessels of the neonate as well as frequent low pulse pressure can make ultrasound less reliable. The diagnosis of a thrombophilic disorder in the neonatal population is unlikely to change management or outcome, and the role of thrombophilia testing in this population requires further study. Treatment of neonatal VTE is aimed at reducing VTE-associated morbidity and mortality. Recommendations for treating, though, cannot be extrapolated from guidelines for older children or adults. Neonates are at risk for bleeding complications, particularly younger neonates with more fragile intracranial vessels. Developmental alterations in the

  17. Performance of magnetic resonance elastography in primary sclerosing cholangitis.

    Science.gov (United States)

    Eaton, John E; Dzyubak, Bogdan; Venkatesh, Sudhakar K; Smyrk, Thomas C; Gores, Gregory J; Ehman, Richard L; LaRusso, Nicholas F; Gossard, Andrea A; Lazaridis, Konstantinos N

    2016-06-01

    Liver stiffness (LS) measured by magnetic resonance elastography (MRE) is emerging as an important biomarker in chronic liver diseases. We examined the diagnostic performance of MRE, factors associated with an increased LS and the prognostic value of LS as measured by MRE among patients with primary sclerosing cholangitis (PSC). We performed a retrospective review of 266 patients with PSC to examine whether LS was associated with the primary endpoint of hepatic decompensation (ascites, variceal hemorrhage and hepatic encephalopathy). The ability of MRE to differentiate stages of fibrosis was examined in a subset of patients who underwent a liver biopsy (n = 20). An LS of 4.93 kPa was the optimal point to detected F4 fibrosis (sensitivity, 1.00; 95% confidence interval (CI), 0.40-1.00; specificity, 0.94; 95%CI, 0.68-1.00). While a serum alkaline phosphatase primary endpoint (hazard ratio, 0.26; 95%CI, 0.01-1.33). However, LS was associated with the development of decompensated liver disease (hazard ratio, 1.55; 95%CI, 1.41-1.70). The optimal LS thresholds that stratified patients at a low, medium and high risk for hepatic decompensation were 6.0 kPa (respectively). Magnetic resonance elastography is able to detect cirrhosis with high specificity and an alkaline phosphatase <1.5 times the upper limit of normal makes the presence of advanced LS unlikely. Moreover, LS obtained by MRE is predictive of hepatic decompensation in PSC. © 2015 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

  18. Computer-aided tumor diagnosis using shear wave breast elastography.

    Science.gov (United States)

    Moon, Woo Kyung; Huang, Yao-Sian; Lee, Yan-Wei; Chang, Shao-Chien; Lo, Chung-Ming; Yang, Min-Chun; Bae, Min Sun; Lee, Su Hyun; Chang, Jung Min; Huang, Chiun-Sheng; Lin, Yi-Ting; Chang, Ruey-Feng

    2017-07-01

    The shear wave elastography (SWE) uses the acoustic radiation force to measure the stiffness of tissues and is less operator dependent in data acquisition compared to strain elastography. However, the reproducibility of the result is still interpreter dependent. The purpose of this study is to develop a computer-aided diagnosis (CAD) method to differentiate benign from malignant breast tumors using SWE images. After applying the level set method to automatically segment the tumor contour and hue-saturation-value color transformation, SWE features including average tissue elasticity, sectional stiffness ratio, and normalized minimum distance for grouped stiffer pixels are calculated. Finally, the performance of CAD based on SWE features are compared with those based on B-mode ultrasound (morphologic and textural) features, and a combination of both feature sets to differentiate benign from malignant tumors. In this study, we use 109 biopsy-proved breast tumors composed of 57 benign and 52 malignant cases. The experimental results show that the sensitivity, specificity, accuracy and the area under the receiver operating characteristic ROC curve (Az value) of CAD are 86.5%, 93.0%, 89.9%, and 0.905 for SWE features whereas they are 86.5%, 80.7%, 83.5% and 0.893 for B-mode features and 90.4%, 94.7%, 92.3% and 0.961 for the combined features. The Az value of combined feature set is significantly higher compared to the B-mode and SWE feature sets (p=0.0296 and p=0.0204, respectively). Our results suggest that the CAD based on SWE features has the potential to improve the performance of classifying breast tumors with US. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. A class of kernel based real-time elastography algorithms.

    Science.gov (United States)

    Kibria, Md Golam; Hasan, Md Kamrul

    2015-08-01

    In this paper, a novel real-time kernel-based and gradient-based Phase Root Seeking (PRS) algorithm for ultrasound elastography is proposed. The signal-to-noise ratio of the strain image resulting from this method is improved by minimizing the cross-correlation discrepancy between the pre- and post-compression radio frequency signals with an adaptive temporal stretching method and employing built-in smoothing through an exponentially weighted neighborhood kernel in the displacement calculation. Unlike conventional PRS algorithms, displacement due to tissue compression is estimated from the root of the weighted average of the zero-lag cross-correlation phases of the pair of corresponding analytic pre- and post-compression windows in the neighborhood kernel. In addition to the proposed one, the other time- and frequency-domain elastography algorithms (Ara et al., 2013; Hussain et al., 2012; Hasan et al., 2012) proposed by our group are also implemented in real-time using Java where the computations are serially executed or parallely executed in multiple processors with efficient memory management. Simulation results using finite element modeling simulation phantom show that the proposed method significantly improves the strain image quality in terms of elastographic signal-to-noise ratio (SNRe), elastographic contrast-to-noise ratio (CNRe) and mean structural similarity (MSSIM) for strains as high as 4% as compared to other reported techniques in the literature. Strain images obtained for the experimental phantom as well as in vivo breast data of malignant or benign masses also show the efficacy of our proposed method over the other reported techniques in the literature. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Transient Elastography for Assessment of Liver Fibrosis and Steatosis: An Evidence-Based Analysis

    Science.gov (United States)

    Brener, S

    2015-01-01

    Background Liver fibrosis is a sign of advanced liver disease and is often an indication for treatment. The current standard for diagnosing liver fibrosis and steatosis is biopsy, but noninvasive alternatives are available; one of the most common is transient elastography (FibroScan). Objectives The objective of this analysis was to assess the diagnostic accuracy and clinical utility of transient elastography alone for liver fibrosis and with controlled attenuation parameter (CAP) for steatosis in patients with hepatitis C virus, hepatitis B virus, nonalcoholic fatty liver disease, alcoholic liver disease, or cholestatic diseases. The analysis also aimed to compare the diagnostic accuracy of transient elastography with two alternative noninvasive technologies: FibroTest and acoustic force radiation impulse (ARFI). Data Sources Ovid MEDLINE, Ovid MEDLINE In-Process, Ovid Embase, and all EBM databases were searched for all studies published prior to October 2, 2014. Review Methods An overview of reviews was conducted using a systematic search and assessment approach. The results of the included systematic reviews were summarized, analyzed, and reported for outcomes related to diagnostic accuracy and clinical utility as a measure of impact on diagnoses, therapeutic decisions, and patient outcomes. Results Fourteen systematic reviews were included, summarizing more than 150 studies. The reviews demonstrated that transient elastography (with or without CAP) has good diagnostic accuracy compared to biopsy for the assessment of liver fibrosis and steatosis. Acoustic force radiation impulse and FibroTest were not superior to transient elastography. Limitations None of the included systematic reviews reported on the clinical utility of transient elastography. Conclusions Transient elastography (with or without CAP) offers a noninvasive alternative to biopsy for the assessment of liver fibrosis and steatosis, given its comparable diagnostic accuracy. PMID:26664664

  1. MR elastography: high rate of technical success in pediatric and young adult patients

    Energy Technology Data Exchange (ETDEWEB)

    Joshi, Madalsa [British Columbia Children' s Hospital, Department of Radiology, Vancouver, BC (Canada); Dillman, Jonathan R.; Towbin, Alexander J.; Serai, Suraj D.; Trout, Andrew T. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, MLC 5031, Cincinnati, OH (United States)

    2017-06-15

    Magnetic resonance (MR) elastography allows the noninvasive assessment of liver stiffness, which is a surrogate for fibrosis. The purpose of this study was to describe our experience using liver MR elastography in a large pediatric population with attention to the frequency and causes of exam failure. Imaging records were searched for patients ≤18 years of age who underwent 2-D gradient recalled echo (GRE) MR elastography of the liver between September 2011 and August 2015 on one of two 1.5-T MRI platforms. Imaging reports and clinical records were reviewed for failed MR elastography acquisitions, factor(s) resulting in failure and whether a subsequent successful examination had been performed. Four hundred sixty-eight MR elastography examinations were performed in 372 patients between 1.5 months and 18 years of age during the study period. Ninety-six percent (450/468) of the examinations were successful. There was no significant difference in mean age (12.6±3.6 vs. 11.2±4.1 years, P=0.12) or body mass index (BMI) (28.2±12.4 vs. 29.5±10 kg/m{sup 2}, P=0.6) between patients with and without successful examinations. MR elastography failures were due to poor paddle positioning resulting in inadequate generation of hepatic shear waves (n=5), iron overload (n=4), patient inability to tolerate MRI (n=3), patient breathing/motion (n=3), artifact from implanted hardware (n=1) and technical malfunction (n=2). Seven of nine (78%) repeat examinations were successful (78%). Hepatic 2-D GRE MR elastography at 1.5 T is technically robust in children. Exam failure is infrequent and largely reflects patient specific factors, some of which can be mitigated with careful technique. (orig.)

  2. Quantitative comparison of transient elastography (TE), shear wave elastography (SWE) and liver biopsy results of patients with chronic liver disease.

    Science.gov (United States)

    Kim, Hyun-Jin; Lee, Hae-Kag; Cho, Jae-Hwan; Yang, Han-Jun

    2015-08-01

    [Purpose] The purpose of this study was to carry out a comparitive analysis of hepatic fibrosis results of the liver hardness of patients with chronic liver disease as measured by elastography (TE), shear wave elastography (SWE), and liver biopsy. [Subjects and Methods] This study was a retrospective analysis of 304 patients who underwent SWE and TE before and after liver biopsy, taken from among patients who had been checked for liver fibrosis by liver biopsy between August 2013 and August 2014. We used receiver operating characteristic (ROC) curve to prove the diagnostic significance of liver stiffness, and then analyzed the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of SWE and TE, as well as the kappa index through cross-analysis of SWE, TE, and liver biopsy. [Results] For liver hardness, the sensitivity of SWE was 84.39%, the specificity of SWE was 97.92%, the accuracy of SWE was 87.33%, the positive predictive value of SWE was 99.32%, and the negative predictive value of SWE was 63.51%. The sensitivity of TE was 94.80%, the specificity of TE was 77.08%, the accuracy of TE was 90.95%, the positive predictive value of TE was 93.97%, and the negative predictive value of TE was 80.43%. [Conclusion] It is our opinion that SWE and TE are non-invasive methods that are more effective than the invasive methods used for diagnosing liver hardness. Invasive methods cover only a section of liver tissue, and are more likely to cause side effects during biopsy.

  3. Probe Oscillation Shear Elastography (PROSE): A High Frame-Rate Method for Two-Dimensional Ultrasound Shear Wave Elastography.

    Science.gov (United States)

    Mellema, Daniel C; Song, Pengfei; Kinnick, Randall R; Urban, Matthew W; Greenleaf, James F; Manduca, Armando; Chen, Shigao

    2016-09-01

    Ultrasound shear wave elastography (SWE) utilizes the propagation of induced shear waves to characterize the shear modulus of soft tissue. Many methods rely on an acoustic radiation force (ARF) "push beam" to generate shear waves. However, specialized hardware is required to generate the push beams, and the thermal stress that is placed upon the ultrasound system, transducer, and tissue by the push beams currently limits the frame-rate to about 1 Hz. These constraints have limited the implementation of ARF to high-end clinical systems. This paper presents Probe Oscillation Shear Elastography (PROSE) as an alternative method to measure tissue elasticity. PROSE generates shear waves using a harmonic mechanical vibration of an ultrasound transducer, while simultaneously detecting motion with the same transducer under pulse-echo mode. Motion of the transducer during detection produces a "strain-like" compression artifact that is coupled with the observed shear waves. A novel symmetric sampling scheme is proposed such that pulse-echo detection events are acquired when the ultrasound transducer returns to the same physical position, allowing the shear waves to be decoupled from the compression artifact. Full field-of-view (FOV) two-dimensional (2D) shear wave speed images were obtained by applying a local frequency estimation (LFE) technique, capable of generating a 2D map from a single frame of shear wave motion. The shear wave imaging frame rate of PROSE is comparable to the vibration frequency, which can be an order of magnitude higher than ARF based techniques. PROSE was able to produce smooth and accurate shear wave images from three homogeneous phantoms with different moduli, with an effective frame rate of 300 Hz. An inclusion phantom study showed that increased vibration frequencies improved the accuracy of inclusion imaging, and allowed targets as small as 6.5 mm to be resolved with good contrast (contrast-to-noise ratio ≥ 19 dB) between the target and

  4. Hemoglobin measured by Hemocue and a reference method in venous and capillary blood: a validation study Hemoglobina medida por Hemocue y por un método de referencia en sangre venosa y capilar: estudio de validación

    Directory of Open Access Journals (Sweden)

    Lynnette Neufeld

    2002-06-01

    Full Text Available Objective. To assess the comparability of hemoglobin concentration (Hb in venous and capillary blood measured by Hemocue and an automated spectrophotometer (Celldyn and to document the influence of type of blood (capillary or venous and analysis method on anemia prevalence estimates. Material and Methods. Between February and May 2000, capillary and venous samples were collected from 72 adults and children at Hospital del Niño Morelense (Morelos State Children's Hospital in Cuernavaca, Morelos, Mexico, and assessed for Hb using the Hemocue and Celldyn methods. Estimated Hb levels were compared using the concordance correlation coefficient and Student's t test for paired data. The sensitivity and specificity for anemia diagnosis were estimated and compared between type of blood and method of assessment. Results. Capillary blood had higher Hb (+0.5g/dl than venous blood in adults and children, as did samples assessed by Celldyn compared to Hemocue (+0.3g/dl. Specificity to detect anemia was adequate (>0.90 but sensitivity was low for capillary blood assessed by Hemocue (Objetivo. Evaluar la comparabilidad de la concentración de hemoglobina (Hb en sangre venosa y capilar medida por Hemocue y por espectrofotómetro automatizado (Celldyn, así como documentar la influencia del tipo de sangre (capilar o venosa y del método de análisis sobre la prevalencia de anemia. Material y métodos. De febrero a mayo de 2000, se recolectaron muestras de sangre capilar y venosa en 72 adultos y niños en el Hospital del Niño Morelense, Cuernavaca, Morelos, México. Se determinaron los niveles de Hb con los métodos Hemocue y Celldyn. Las cifras de Hb estimadas se compararon con el coeficiente de concordancia y la prueba pareada de t de Student. También se comparó la sensibilidad y especificidad para el diagnóstico de anemia, utilizando sangre de los dos tipos y métodos de análisis. Resultados. La Hb fue mayor en sangre capilar comparada con sangre venosa

  5. [Duplexsonography investigation in patients with venous ulcer].

    Science.gov (United States)

    Jeanneret-Gris, Christina

    2011-03-01

    Venous hypertension due to venous insufficiency causes venous ulcers. Duplexsonography is a widely accepted non invasive method to assess venous insufficiency with venous reflux measurements. Retrograde venous flow is defined as venous reflux. The testing of venous reflux is reliable if transvalvular pressure is sufficiently high and transvalvular flow velocity exceeds 30 cm/s. Reflux testing in the proximal leg veins (V. femoralis communis, V. femoralis, V. saphena magna) is done using a standardised Valsalva Manoeuvre (exspiration into a tube up to a pressure of 30 mmHg, pressure established within 0.5 seconds, pressure hold for 3 seconds). Distal leg vein testing (V. poplitea, V. tibialis posterior, V. saphena parva) is recommended with a two handed - compression distally to the tested veins. The most important parameter is venous reflux time, a cut off of > 2 seconds is recommended.

  6. Developmental venous anomaly (DVA); Developmental Venous Anomaly (DVA)

    Energy Technology Data Exchange (ETDEWEB)

    Zimmer, A.; Ahlhelm, F.; Viera, J.; Reith, W.; Schulte-Altedorneburg, G. [Universitaetsklinikum des Saarlandes, Klinik fuer Diagnostische und Interventionelle Neuroradiologie, Homburg/Saar (Germany); Hagen, T. [Radiologische Praxis, Augsburg (Germany)

    2007-10-15

    As congenital anatomic variants of venous drainage, developmental venous anomalies (DVA) represent up to 60% of all cerebral vascular malformations. The prior term ''venous angioma'' is a misnomer implicating an abnormal vascular structure with an increased bleeding risk. They are often found incidentally and are hardly ever symptomatic. Their morphologic characteristics are dilated vessels in the white matter, which converge on a greater collector vein, forming the typical caput medusae. They drain into the superficial or deep venous system. The frequent association with other, potentially bleeding-prone vascular malformations is clinically relevant, in particular cavernous angioma, which might require therapeutic action. Therefore, coincident vascular lesions need to be actively sought by appropriate additional imaging techniques. (orig.) [German] Als eine embryologische Variante der venoesen Drainage macht die so genannte ''developmental venous anomaly'' (DVA) etwa 60% aller zerebralen vaskulaeren Malformationen aus. Der vormalige Terminus ''venoeses Angiom'' sollte nicht mehr benutzt werden, da er abnormale Gefaessstrukturen mit einem erhoehten Blutungsrisiko impliziert. Die DVA werden oft inzidentell entdeckt und sind nur selten symptomatisch. Das typische Erscheinungsbild ist durch dilatierte, medusenhauptartig angeordnete venoese Marklagergefaesse gekennzeichnet, die in eine groessere Sammelvene drainieren. Der Abfluss erfolgt ueber das oberflaechliche oder tiefe Venensystem. Klinisch wichtig ist die haeufige Assoziation mit anderen zerebralen Gefaessmalformationen, insbesondere kavernoesen Angiomen, nach denen im Rahmen der Diagnostik explizit gesucht werden muss, da diese eine potenzielle Blutungsquelle darstellen und ein therapeutisches Vorgehen erfordern koennen. (orig.)

  7. Comparison of diagnostic accuracies of two- and three-dimensional MR elastography of the liver.

    Science.gov (United States)

    Morisaka, Hiroyuki; Motosugi, Utaroh; Glaser, Kevin J; Ichikawa, Shintaro; Ehman, Richard L; Sano, Katsuhiro; Ichikawa, Tomoaki; Onishi, Hiroshi

    2017-04-01

    To evaluate the effect of imaging sequence (spin-echo echo-planar imaging [EPI] and gradient-echo [GRE]) and postprocessing method (two-dimensional [2D] and 3D inversion algorithms) on liver MR elastography (MRE) and to validate the diagnostic performance of EPI-MRE3D versus conventional GRE-MRE2D for liver fibrosis staging. Three MRE methods (EPI-MRE3D , EPI-MRE2D , and GRE-MRE2D ) were performed on soft and mildly stiff phantoms and 58 patients with chronic liver disease using a 3 Tesla clinical MRI scanner, and stiffness values were compared among the three methods. A validation study comprised 73 patients with histological liver fibrosis (F0-4, METAVIR system). Areas under the receiver operating characteristic curves (AUCs) and accuracies for diagnosing significant fibrosis (F3-4) and cirrhosis (F4) were compared between EPI-MRE3D and GRE-MRE2D . Stiffness values of the soft and mildly stiff phantoms were 2.4 kPa and 4.0 kPa by EPI-MRE3D ; 2.6 kPa and 4.2 kPa by EPI-MRE2D ; and 2.7 kPa and 4.2 kPa by GRE-MRE2D . In patients, EPI-MRE3D provided significantly lower stiffness values than other methods (P F4) (all P < 0.005). EPI-MRE3D showed modestly lower liver stiffness values than conventional GRE-MRE2D . The diagnostic performances of EPI-MRE3D and GRE-MRE2D were equivalent for liver fibrosis staging. 3 J. Magn. Reson. Imaging 2017;45:1163-1170. © 2016 International Society for Magnetic Resonance in Medicine.

  8. Venous chest anatomy: clinical implications

    Energy Technology Data Exchange (ETDEWEB)

    Chasen, M.H.; Charnsangavej, C. [Department of Diagnostic Imaging, The University of Texas, M.D. Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, Texas 77030 (United States)

    1998-03-01

    This article provides a practical approach to the clinical implications and importance of understanding the collateral venous anatomy of the thorax. Routine radiography, conventional venography, computed tomography (CT), and magnetic resonance (MR) imaging studies provide correlative anatomic models for the demonstration of how interconnecting collateral vascular networks within the thorax maintain venous stability at all times. Five major systems comprise the collateral venous network of the thorax ( Fig. 1 ). These include the paravertebral, azygos-hemiazygos, internal mammary, lateral thoracic, and anterior jugular venous systems (AJVS). The five systems are presented in the following sequence: (a) a brief introduction to the importance of catheter position and malposition in understanding access to the thoracic venous system, (b) the anatomy of the azygos-hemiazygos systems and their relationship with the paravertebral plexus, (c) the importance of the AJVS, (d) 'loop' concepts interconnecting the internal mammary and azygos-hemiazygos systems by means of the lateral thoracic and intercostal veins, and (e) the interconnecting venous networks on the thoracic side of the thoracoabdominal junction. Certain aspects of the venous anatomy of the thorax will not be discussed in this chapter and include (a) the intra-abdominal anastomoses between the superior and inferior vena cavae (IVC) via the internal mammary, lateral thoracic, and azygos-hemiazygos systems (beyond the scope of this article), (b) potential collateral vessels involving vertebral, parascapular, thyroidal, thymic, and other smaller veins that might anastomose with the major systems, and (c) anatomic variants and pitfalls that may mimic pathologic conditions (space limitations). (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  9. Contemporary diagnosis of venous malformation

    Directory of Open Access Journals (Sweden)

    Lee BB

    2013-11-01

    Full Text Available BB Lee,1 I Baumgartner21Department of Surgery, George Washington University, Washington, DC, USA; 2Swiss Cardiovascular Center, University Hospital Bern, Bern, SwitzerlandAbstract: Venous malformation is a congenital vascular malformation resulting from defective development during various stages of embryogenesis and selectively affecting the venous system. Depending on the embryologic stage when the developmental arrest occurred, the clinical presentation of venous malformation is extremely variable in location, extent, severity, natural progression, and hemodynamic impact. Extratruncular lesions occur in the earlier stages of embryonic life, and retain characteristics unique to mesenchymal cells (angioblasts, growing and proliferating when stimulated internally (eg, by menarche, pregnancy, and hormones or externally (eg, by trauma or surgery. These lesions also have a significant hemodynamic impact on the venous system involved, in addition to the risk of localized intravascular coagulopathy. However, truncal lesions, as defective developments along the late stage, no longer carry the risk of proliferation and recurrence due to lack of mesenchymal characteristics. Although, they often have serious hemodynamic consequences due to direct involvement of the main vein trunk. Therefore, a thorough clinical history and careful physical examination should be followed by an appropriate combination of noninvasive and less invasive tests (eg, Doppler ultrasonography, magnetic resonance imaging, computed tomography to confirm the clinical impression as well as to define the extent and severity of the venous malformation. Invasive tests, eg, phlebography or angiography, are seldom needed for the diagnosis per se. Additional evaluation for coagulation abnormalities, eg, D-dimer and fibrinogen levels, is generally recommended, especially for the treatment of surgery and endovascular candidates with extensive lesions to assess the localized intravascular

  10. In Vitro Comparison of Five Different Elastography Systems for Clinical Applications, Using Strain and Shear Wave Technology.

    Science.gov (United States)

    Mulabecirovic, Anesa; Vesterhus, Mette; Gilja, Odd Helge; Havre, Roald Flesland

    2016-11-01

    Several different platforms providing ultrasound elastography have emerged in recent years. In this in vitro study on a single tissue-mimicking phantom (CIRS Model 49), we aimed to compare the performance of quantitative elastography measurements from platforms running strain elastography and others running shear wave elastography. We evaluated five different elastography platforms using both linear and curvilinear probes. All measurements were performed in parallel by two independent investigators who recorded the elasticity quantitatively. We investigated intra- and inter-observer agreement by intra-class correlation analysis and coefficient of variation, by correlation and limits of agreement. The reproducibility of elasticity measurements was good to excellent for shear wave and strain elastography. All five elastography platforms had high intra-observer (intra-class correlation coefficient: 0.932-1.0) and inter-observer correlation (intra-class correlation coefficient: 0.845-0.996). All inclusions could be differentiated by quantitative elastography by all systems (p < 0.001). The use of a linear probe yielded more reproducible measurements compared with use of a convex probe in 3/4 platforms. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  11. Efficacy of an artificial neural network-based approach to endoscopic ultrasound elastography in diagnosis of focal pancreatic masses

    DEFF Research Database (Denmark)

    Săftoiu, Adrian; Vilmann, Peter; Gorunescu, Florin

    2012-01-01

    By using strain assessment, real-time endoscopic ultrasound (EUS) elastography provides additional information about a lesion's characteristics in the pancreas. We assessed the accuracy of real-time EUS elastography in focal pancreatic lesions using computer-aided diagnosis by artificial neural...

  12. Two-dimensional shear-wave elastography on conventional ultrasound scanners with time-aligned sequential tracking (TAST) and comb-push ultrasound shear elastography (CUSE).

    Science.gov (United States)

    Song, Pengfei; Macdonald, Michael; Behler, Russell; Lanning, Justin; Wang, Michael; Urban, Matthew; Manduca, Armando; Zhao, Heng; Callstrom, Matthew; Alizad, Azra; Greenleaf, James; Chen, Shigao

    2015-02-01

    Two-dimensional shear-wave elastography presents 2-D quantitative shear elasticity maps of tissue, which are clinically useful for both focal lesion detection and diffuse disease diagnosis. Realization of 2-D shear-wave elastography on conventional ultrasound scanners, however, is challenging because of the low tracking pulse-repetition-frequency (PRF) of these systems. Although some clinical and research platforms support software beamforming and plane-wave imaging with high PRF, the majority of current clinical ultrasound systems do not have the software beamforming capability, which presents a critical challenge for translating the 2-D shear-wave elastography technique from laboratory to clinical scanners. To address this challenge, this paper presents a time-aligned sequential tracking (TAST) method for shear-wave tracking on conventional ultrasound scanners. TAST takes advantage of the parallel beamforming capability of conventional systems and realizes high-PRF shear-wave tracking by sequentially firing tracking vectors and aligning shear wave data in the temporal direction. The comb-push ultrasound shear elastography (CUSE) technique was used to simultaneously produce multiple shear wave sources within the field-of-view (FOV) to enhance shear wave SNR and facilitate robust reconstructions of 2-D elasticity maps. TAST and CUSE were realized on a conventional ultrasound scanner. A phantom study showed that the shear-wave speed measurements from the conventional ultrasound scanner were in good agreement with the values measured from other 2-D shear wave imaging technologies. An inclusion phantom study showed that the conventional ultrasound scanner had comparable performance to a state-of-the-art shear-wave imaging system in terms of bias and precision in measuring different sized inclusions. Finally, in vivo case analysis of a breast with a malignant mass, and a liver from a healthy subject demonstrated the feasibility of using the conventional ultrasound

  13. Two-dimensional Shear Wave Elastography on Conventional Ultrasound Scanners with Time Aligned Sequential Tracking (TAST) and Comb-push Ultrasound Shear Elastography (CUSE)

    Science.gov (United States)

    Song, Pengfei; Macdonald, Michael C.; Behler, Russell H.; Lanning, Justin D.; Wang, Michael H.; Urban, Matthew W.; Manduca, Armando; Zhao, Heng; Callstrom, Matthew R.; Alizad, Azra; Greenleaf, James F.; Chen, Shigao

    2014-01-01

    Two-dimensional (2D) shear wave elastography presents 2D quantitative shear elasticity maps of tissue, which are clinically useful for both focal lesion detection and diffuse disease diagnosis. Realization of 2D shear wave elastography on conventional ultrasound scanners, however, is challenging due to the low tracking pulse-repetition-frequency (PRF) of these systems. While some clinical and research platforms support software beamforming and plane wave imaging with high PRF, the majority of current clinical ultrasound systems do not have the software beamforming capability, which presents a critical challenge for translating the 2D shear wave elastography technique from laboratory to clinical scanners. To address this challenge, this paper presents a Time Aligned Sequential Tracking (TAST) method for shear wave tracking on conventional ultrasound scanners. TAST takes advantage of the parallel beamforming capability of conventional systems and realizes high PRF shear wave tracking by sequentially firing tracking vectors and aligning shear wave data in the temporal direction. The Comb-push Ultrasound Shear Elastography (CUSE) technique was used to simultaneously produce multiple shear wave sources within the field-of-view (FOV) to enhance shear wave signal-to-noise-ratio (SNR) and facilitate robust reconstructions of 2D elasticity maps. TAST and CUSE were realized on a conventional ultrasound scanner (the General Electric LOGIQ E9). A phantom study showed that the shear wave speed measurements from the LOGIQ E9 were in good agreement to the values measured from other 2D shear wave imaging technologies. An inclusion phantom study showed that the LOGIQ E9 had comparable performance to the Aixplorer (Supersonic Imagine) in terms of bias and precision in measuring different sized inclusions. Finally, in vivo case analysis of a breast with a malignant mass, and a liver from a healthy subject demonstrated the feasibility of using the LOGIQ E9 for in vivo 2D shear wave

  14. Regional diagnosis of lymphoedema and selection of sites for lymphaticovenular anastomosis using elastography

    Energy Technology Data Exchange (ETDEWEB)

    Mihara, M., E-mail: mihara@keiseigeka.name [Department of Plastic Surgery and Reconstructive Surgery, University of Tokyo, Tokyo (Japan); Hayashi, Y. [Department of Plastic Surgery and Reconstructive Surgery, University of Tokyo, Tokyo (Japan); Murai, N. [Department of Vascular Surgery, Saiseikai Kawaguchi Hospital, Saitama, Saitamaken (Japan); Moriguchi, H.; Iida, T.; Hara, H.; Todokoro, T.; Narushima, M.; Uchida, G.; Koshima, I. [Department of Plastic Surgery and Reconstructive Surgery, University of Tokyo, Tokyo (Japan)

    2011-08-15

    Aim: To evaluate the use of ultrasound elastography as a basis for determining the most appropriate sites for lymphaticovenular anastomosis (LVA) for treatment of lymphoedema. Materials and methods: Preoperative elastography and LVA were performed in 11 patients (11 legs) with leg lymphoedema, including two cases of primary oedema and nine of secondary oedema. Results: The mean number of LVAs applied per leg was 4.4 (range 3-7). The mean reduction in the leg circumference was 91.7%, and 10 of the 11 cases (90.0%) were improved. Hardness was reduced from a mean of 1.6 before surgery to 0.9 after surgery, and improvement was also noted in 10 cases (90.9%). The severity of oedema was determined in five regions in each leg, and was classified as elastography stage (ES) 0 in 11 regions, ES1 in 23, ES2 in 15, and ES3 in six. Conclusions: These results demonstrate the value of ultrasound elastography for the diagnosis of early-stage lymphoedema and determination of LVA sites. This is the first report of diagnosis of lymphoedema using elastography and the findings suggest that this procedure followed by LVA could be used as a new therapeutic method for early-stage lymphoedema.

  15. Considering Angle Selection When Using Ultrasound Electrode Displacement Elastography to Evaluate Radiofrequency Ablation of Tissues

    Directory of Open Access Journals (Sweden)

    Jingjing Xia

    2014-01-01

    Full Text Available Percutaneous radiofrequency ablation (RFA is a minimally invasive treatment to thermally destroy tumors. Ultrasound-based electrode-displacement elastography is an emerging technique for evaluating the region of RFA-induced lesions. The angle between the imaging probe and the RFA electrode can influence electrode-displacement elastography when visualizing the ablation zone. We explored the angle effect on electrode-displacement elastography to measure the ablation zone. Phantoms embedded with meatballs were fabricated and then ablated using an RFA system to simulate RFA-induced lesions. For each phantom, a commercial ultrasound scanner with a 7.5 MHz linear probe was used to acquire raw image data at different angles, ranging from 30° to 90° at increments of 10°, to construct electrode-displacement images and facilitate comparisons with tissue section images. The results revealed that the ablation regions detected using electrode-displacement elastography were highly correlated with those from tissue section images when the angle was between 30° and 60°. However, the boundaries of lesions were difficult to distinguish, when the angle was larger than 60°. The experimental findings suggest that angle selection should be considered to achieve reliable electrode-displacement elastography to describe ablation zones.

  16. Acoustic radiation force impulse (ARFI elastography of testicular disorders in dogs: preliminary results

    Directory of Open Access Journals (Sweden)

    M.A.R. Feliciano

    2016-04-01

    Full Text Available The aim of this study was to describe the use of acoustic radiation force impulse (ARFI elastography in the evaluation of testicular disorders in dogs. Eighteen dogs with testicular disorders (thirty-six testicles were assessed. Echotexture, size, contours and margins of testes were analysed by ultrasonography. Deformities and tissue stiffness (greyscale and homogenous or heterogeneous were evaluated by qualitative elastography and shear velocity was determined quantitatively. Subsequent to orchiectomy, testicular samples were collected for histopathology analysis and thirty-six disorders were identified. Qualitative elastography revealed that normal healthy testicular tissues were homogenous and not pliable while the affected testicles had alterations in tissue stiffness and homogeneity. The values obtained for quantitative elastography of the testicular tissues were: normal/healthy - 1.30±0.12 m/s; degenerated - 0.97±0.08 m/s; atrophied - 2.00±0.35 m/s; hypoplastic - 0.82±0.2 m/s; cystic - 1.32±0.18 m/s; orchitis - 2.68±0.42 m/s; interstitial cell tumours - 3.32±0.65 m/s; sertolioma - 2.99±0.07 m/s and leydigoma - 2.73±0.37. ARFI elastography of abnormal testes proved to be an applicable and complementary technique in the diagnosis of testicular disease in dogs.

  17. Voxel-level reproducibility assessment of modality independent elastography in a pre-clinical murine model

    Science.gov (United States)

    Flint, Katelyn M.; Weis, Jared A.; Yankeelov, Thomas E.; Miga, Michael I.

    2015-03-01

    Changes in tissue mechanical properties, measured non-invasively by elastography methods, have been shown to be an important diagnostic tool, particularly for cancer. Tissue elasticity information, tracked over the course of therapy, may be an important prognostic indicator of tumor response to treatment. While many elastography techniques exist, this work reports on the use of a novel form of elastography that uses image texture to reconstruct elastic property distributions in tissue (i.e., a modality independent elastography (MIE) method) within the context of a pre-clinical breast cancer system.1,2 The elasticity results have previously shown good correlation with independent mechanical testing.1 Furthermore, MIE has been successfully utilized to localize and characterize lesions in both phantom experiments and simulation experiments with clinical data.2,3 However, the reproducibility of this method has not been characterized in previous work. The goal of this study is to evaluate voxel-level reproducibility of MIE in a pre-clinical model of breast cancer. Bland-Altman analysis of co-registered repeat MIE scans in this preliminary study showed a reproducibility index of 24.7% (scaled to a percent of maximum stiffness) at the voxel level. As opposed to many reports in the magnetic resonance elastography (MRE) literature that speak to reproducibility measures of the bulk organ, these results establish MIE reproducibility at the voxel level; i.e., the reproducibility of locally-defined mechanical property measurements throughout the tumor volume.

  18. Shear wave elastography contribution in ultrasound diagnosis management of breast lesions.

    Science.gov (United States)

    Klotz, T; Boussion, V; Kwiatkowski, F; Dieu-de Fraissinette, V; Bailly-Glatre, A; Lemery, S; Boyer, L

    2014-09-01

    To determine the diagnosis performance of shear wave elastography in the differentiation of benign and malignant breast lesions and the factors influencing the elasticity values. To suggest an appropriate management of breast lesions using the ultrasound-elastography combination. Monocentric retrospective study of 167 breast lesions classified by conventional ultrasound as BI-RADS category 3 or higher that underwent an elastography study and histological analysis. The analysis of qualitative parameters, according to the classification established in this study, allows us to obtain a sensitivity of 91.1% and a specificity of 92.3%. These values are very close to or better than the quantitative parameters Emax and Emean. Different Emax thresholds values were established based on the long axis of the lesion and its palpable character, which appeared to be significant factors influencing elasticity. The management of breast lesions by combining ultrasound and elastography, as proposed here, allows us to keep the sensitivity of an ultrasound (96%), while doubling its specificity (86.2% versus 43.1%). With the complementary nature of their performance, the combination of conventional ultrasound and shear wave elastography can improve the management of breast lesions. The qualitative classification proposed appears to be relevant assistance in lesion characterization. Copyright © 2014 Éditions françaises de radiologie. Published by Elsevier Masson SAS. All rights reserved.

  19. Systemic venous drainage: can we help Newton?

    Science.gov (United States)

    Corno, Antonio F

    2007-06-01

    In recent years substantial progress occurred in the techniques of cardiopulmonary bypass, but the factor potentially limiting the flexibility of cardiopulmonary bypass remains the drainage of the systemic venous return. In the daily clinical practice of cardiac surgery, the amount of systemic venous return on cardiopulmonary bypass is directly correlated with the amount of the pump flow. As a consequence, the pump flow is limited by the amount of venous return that the pump is receiving. On cardiopulmonary bypass the amount of venous drainage depends upon the central venous pressure, the height differential between patient and inlet of the venous line into the venous reservoir, and the resistance in the venous cannula(s) and circuit. The factors determining the venous return to be taken into consideration in cardiac surgery are the following: (a) characteristics of the individual patient; (b) type of planned surgical procedure; (c) type of venous cannula(s); (d) type of circuit for cardiopulmonary bypass; (e) strategy of cardiopulmonary bypass; (f) use of accessory mechanical systems to increased the systemic venous return. The careful pre-operative evaluation of all the elements affecting the systemic venous drainage, including the characteristics of the individual patient and the type of required surgical procedure, the choice of the best strategy of cardiopulmonary bypass, and the use of the most advanced materials and tools, can provide a systemic venous drainage substantially better than what it would be allowed by the simple "Law of universal gravitation" by Isaac Newton.

  20. Cerebral venous thrombosis in childhood

    Energy Technology Data Exchange (ETDEWEB)

    Huisman, T.A.G.M.; Martin, E.; Willi, U.V. [Dept. of Diagnostic Imaging and Radiology, University Children' s Hospital Zurich (Switzerland); Holzmann, D. [Dept. of Otorhinolaryngology, University Children' s Hospital Zurich, Zurich (Switzerland)

    2001-09-01

    This was a retrospective study to determine different etiologies of cerebral venous thrombosis (CVT) in childhood and to correlate extent and location of thrombosis with the etiology and the age of the child as well as the final outcome. In addition, the radiologic approach is discussed. This was a retrospective analysis of 19 children with CVT. The children were examined by contrast-enhanced dynamic CT. Radiologic findings were correlated with the etiology of CVT. Cerebral venous thrombosis is not as infrequent in children as has been thought. Cerebral venous thrombosis in children can occur due to trauma (n=9), infections (n=7), or coagulation disorders (n=3). Extent and location of thrombosis, as well as complications, final outcome, and therapy, depend on the etiology. Computed tomography remains a valuable primary imaging modality in the diagnosis of CVT in the acutely injured or diseased child. (orig.)

  1. Dutch Venous Ulcer guideline update.

    Science.gov (United States)

    Maessen-Visch, M Birgitte; de Roos, Kees-Peter

    2014-05-01

    The revised guideline of 2013 is an update of the 2005 guideline "venous leg ulcer". In this special project four separate guidelines (venous leg ulcer, varicose veins, compression therapy and deep venous disorders) were revised and developed simultaneously. A meeting was held including representatives of any organisation involved in venous disease management including patient organizations and health insurance companies. Eighteen clinical questions where defined, and a new strategy was used to accelerate the process. This resulted in two new and two revised guidelines within one year. The guideline committee advises use of the C of the CEAP classification as well as the Venous Clinical Severity Score (VCSS) and a Quality of life (QoL) score in the assessment of clinical signs. These can provide insight into the burden of disease and the effects of treatment as experienced by the patient. A duplex ultrasound should be performed in every patient to establish the underlying aetiology and to evaluate the need for treatment (which is discussed in a separate guideline). The use of the TIME model for describing venous ulcers is recommended. There is no evidence for antiseptic or antibiotic wound care products except for a Cochrane review in which some evidence is presented for cadexomer iodine. Signs of infection are the main reason for the use of oral antibiotics. When the ulcer fails to heal the use of oral aspirin and pentoxifylline can be considered as an adjunct. For the individual patient, the following aspects should be considered: the appearance of the ulcer (amount of exudate) according to the TIME model, the influence of wound care products on moisturising the wound, frequency of changing compression bandages, pain and allergies. The cost of the dressings should also be considered. Education and training of patients t improves compliance with compression therapy but does not influence wound healing rates. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  2. Ultrasonic Elastography Features of Phyllodes Tumors of the Breast: A Clinical Research

    Science.gov (United States)

    Ou, Bing; Luo, Bao-Ming; Xiao, Xiao-Yun; Zhong, Wen-Jing; Zhao, Xin-Bao; Zhao, Zi-Zhuo; Yang, Hai-Yun; Zhi, Hui

    2014-01-01

    The purpose of this study was to analyze the ultrasonic elastography features of phyllodes tumors of the breast comparing with fibroadenomas. A retrospective database was queried for the patients diagnosed as phyllodes tumors and fibroadenomas at Sun Yat-sen Memorial Hospital from January 2008 to August 2012. Three hundred and fifty lesions from 323 consecutive patients were included in the study. All the cases were examined by conventional ultrasonography and ultrasound elastography. Ultrasound elastography was used to calculate strain ratio of the lesions with bilateral breast tissue at the same depth as reference. There were 36 phyllodes tumors (27 benign, 8 borderline, 1 malignant) and 314 fibroadenomas (158 the pericanalicular type, 103 the intracanalicular type, 53 other special types). The strain ratio for phyllodes tumors (3.19±2.33) was significantly higher than for fibroadenomas (1.69±0.88) (pphyllodes tumors from fibroadenoma in breast. PMID:24454830

  3. Magnetomotive colon elastography: preliminary assessment; Elastografia magnetomotriz da regiao do colon: avaliacao preliminar em phantoms

    Energy Technology Data Exchange (ETDEWEB)

    Bruno, A. Colello, E-mail: alexandrecolellobruno@usp.br [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Medicina; Grillo, F.W.; Sampaio, D.R.T.; Carneiro, A.A.O. [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Filosofia Ciencias e Letras

    2015-08-15

    Colorectal cancer (CRC) is the third most common malignant neoplasm worldwide and early diagnosis reduces morbidity. The standard preventive exams methods are uncomfortable for the patient, invasive, and /or are ionizing. Here, we evaluate the potential of magneto-motive ultrasound (MMUS) as a new, minimally invasive CRC screening technique. We developed a hybrid transducer (comprised of an ultrasound probe and a magnetic coil system) to construct relative elastography maps in a paraffin phantom with isoechoic inclusions. The electromagnetic component of our system manipulated ferromagnetic fluid located inside of our synthetic colon, and the captured ultrasound images were used to produce relative elastography maps. The MMUS images reveal by otherwise invisible structures based on differences in stiffness. Ultrasound elastography (relative) images by MMUs technique complements usual preventive CRC exams, is minimally invasive, has relative low cost when compared with others image methods. Also is fast diagnose and more comfortable for patient which prevents withdrawal of the screening. (author)

  4. Ultrasound elastography and diffusion weighted MRI in patients with rectal cancer

    DEFF Research Database (Denmark)

    Rafaelsen, Søren Rafael; Vagn-Hansen, Chris Aksel; Sørensen, Torben

    OBJECTIVE: The current literature has described the usefulness of elastography and diffusion weighted MRI in cancer patients, but to the best of our knowledge so far none of them have compared the two new methods. The tumour cell density is related to the MRI measured apparent diffusion weighted .......59), P ADC measurements in rectal tumours. The relationship between ARFI and ADC measurement was linear in our study population....... coefficient (ADC). The purpose of the present study was to compare quantitative elastography based on ultrasound shear wave measurements with MRI ADC. METHODS AND MATERIALS: We prospectively examined consecutive 52 patients with histopathological proven rectal cancer. The tumour elasticity was measured using...... the Acoustic Radiation Force Impulse (ARFI) to generate information on the mechanical properties of the tissue. The objective quantitative elastography shear wave velocity was blindly compared to the ADC measurements using a 1.5 Tesla MRI system. The study was approved by the local Clinical Ethics Committee...

  5. Case study: could ultrasound and elastography visualized densified areas inside the deep fascia?

    Science.gov (United States)

    Luomala, Tuulia; Pihlman, Mika; Heiskanen, Jouko; Stecco, Carla

    2014-07-01

    Many manual techniques describe palpable changes in the subcutaneous tissue. Many manual therapists have perceived palpable tissue stiffness and how it changes after treatment. No clear demonstration exists of the presence of specific alterations in the subcutaneous tissue and even less a visualization of their changes following manual therapy. This case study visualizes by ultrasound and elastography an alteration of the deep fascia in a 40-year-old male with subacute pain in the calf area. Ultrasound and elastography permits visualization of gliding, echogenicity and elasticity of deep fascia and their changes, after manual therapy (Fascial Manipulation(©)). This study suggests the possible use of the ultrasound and elastography to furnish a more objective picture of the "sensations" that are commonly reported by manual therapists, and which supports clinicians in the diagnosis of the myofascial pain. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. A young man with nonhealing venous ulcers

    NARCIS (Netherlands)

    Vloedbeld, M. G.; Venema, A. W.; Smit, A. J.

    A 35-year-old man presented with nonhealing ulcers at an atypical location on his left foot, caused by a combination of venous insufficiency (after deep venous thrombosis) and arterial insufficiency. The underlying cause was Buerger's disease.

  7. Traditional Long-Term Central Venous Catheters Versus Transhepatic Venous Catheters in Infants and Young Children.

    Science.gov (United States)

    Marshall, Amanda Marie; Danford, David A; Curzon, Christopher L; Anderson, Venus; Delaney, Jeffrey W

    2017-10-01

    Children with congenital heart disease may require long-term central venous access for intensive care management; however, central venous access must also be preserved for future surgical and catheterization procedures. Transhepatic venous catheters may be an useful alternative. The objective of this study was to compare transhepatic venous catheters with traditional central venous catheters regarding complication rate and duration of catheter service. Retrospective review of 12 congenital heart disease patients from September 2013 to July 2015 who underwent placement of one or more transhepatic venous catheters. Single freestanding pediatric hospital located in the central United States. Pediatric patients with congenital heart disease who underwent placement of transhepatic venous catheter. Cohort's central venous catheter complication rates and duration of catheter service were compared with transhepatic venous catheter data. Twelve patients had a total of 19 transhepatic venous lines. Transhepatic venous lines had a significantly longer duration of service than central venous lines (p = 0.001). No difference between the two groups was found in the number of documented thrombi, thrombolytic burden, or catheter sites requiring wound care consultation. A higher frequency of infection in transhepatic venous lines versus central venous lines was found, isolated to four transhepatic venous lines that had a total of nine infections. All but one was successfully managed without catheter removal. The difference in the proportion of infections to catheters in transhepatic venous lines versus central venous lines was significant (p = 0.0001), but no difference in the rate of infection-related catheter removal was found. Without compromising future central venous access sites, transhepatic venous lines had superior duration of service without increased thrombosis, thrombolytic use, or insertion site complications relative to central venous lines. Transhepatic venous

  8. Dynamics of the liver stiffness value using transient elastography during the perioperative period in patients with valvular heart disease.

    Directory of Open Access Journals (Sweden)

    Young Eun Chon

    Full Text Available Liver congestion due to heart failure in patients with valvular heart disease (VHD can result in an overestimate of the liver stiffness (LS as assessed by transient elastography (TE. This prospective pilot study investigated the dynamics of LS during the perioperative valve operation period.Thirty-two patients who underwent a valve operation (case and 12 who underwent a varicose vein operation (control were prospectively enrolled. LS and cardiologic parameters at three time points [baseline, post-operative day (POD7, and POD90] were collected.LS at three time points were consistently higher in the case group than those in the control group, although all participants did not show evidence of underlying chronic liver disease (all P<0.05. In the case group, LS at POD7 increased slightly from the LS at baseline (median 7.9→8.4 kPa, P = 0.816, whereas LS at POD90 decreased significantly from the LS at POD7 (median 8.4→6.0 kPa; P = 0.026. LS was significantly correlated with N-terminal-pro brain natriuretic peptide (NT-proBNP (ρ = 0.412, left ventricular ejection fraction (ρ = -0.494, and central venous pressure during the operation (ρ = 0.555 at baseline (all P<0.05. LS was significantly correlated with NT-proBNP (ρ = 0.526 and right ventricular pressure (ρ = 0.572 at POD7, whereas LS was significantly correlated with NT-proBNP (ρ = 0.590 at POD90 (all P<0.05.LS can be overestimated in patients with VHD due to hepatic congestion. However, LS can be dynamically reversed during the perioperative period reflecting the restoration of cardiac function after a successful operation.

  9. Venous leg ulcer in the context of chronic venous disease.

    Science.gov (United States)

    Lozano Sánchez, F S; Marinel lo Roura, J; Carrasco Carrasco, E; González-Porras, J R; Escudero Rodríguez, J R; Sánchez Nevarez, I; Díaz Sánchez, S

    2014-05-01

    Chronic venous disease (CVD) is a frequent disorder with a high socioeconomic impact. Little is known about the possible differences between healed ulcer (C5 group) and active ulcer (C6 group) in terms of disease severity and quality of life (QoL). Our aim was to determine the possible differences in severity disease and QoL between the C5-C6 and C1 (control) group. Data from a national, multicentre, observational and cross-sectional study (n = 1598) were used to compare three groups of CVD: C1 (n = 243), C5 (n = 136) and C6 (n = 70). CVD severity was assessed with the Venous Clinical Severity Score (VCSS) and QoL with the Short Form 12 Health Survey (SF-12) and Chronic Lower Limb Venous Insufficiency Questionnaire (CIVIQ-20). Patients with active ulcers had a higher mean total VCSS than patients with healed ulcers (P ulcers than in those with C1 (P ulcers (C6) had lower QoL scores, but the differences were not statistically significant. Patients with venous leg ulcers (C5-C6) are associated with high severity and poor QoL. However, the healing of a leg ulcer did not contribute to improvement of QoL.

  10. A comparative study of strain and shear-wave elastography in an elasticity phantom.

    Science.gov (United States)

    Carlsen, Jonathan F; Pedersen, Malene R; Ewertsen, Caroline; Săftoiu, Adrian; Lönn, Lars; Rafaelsen, Søren R; Nielsen, Michael B

    2015-03-01

    OBJECTIVE. The purpose of this study was to assess the diagnostic accuracy of strain and shear-wave elastography for determining targets of varying stiffness in a phantom. The effect of target diameter on elastographic assessments and the effect of depth on shear-wave velocity were also investigated. MATERIALS AND METHODS. We examined 20 targets of varying diameters (2.5-16.7 mm) and stiffnesses (8, 14, 45, and 80 kPa) with a 4-9-MHz linear-array transducer. Targets were evaluated 10 times with three different methods-shear-wave elastography, strain ratio, and strain histogram analysis-yielding 600 evaluations. AUCs were calculated for data divided between different stiffnesses. A 1.5-6-MHz curved-array transducer was used to assess the effect of depth (3.5 vs 6 cm) on shear-wave elastography in 80 scans. Mixed model analysis was performed to assess the effect of target diameter and depth. RESULTS. Strain ratio and strain histogram AUCs were higher than the shear-wave velocity AUC (p < 0.001) in data divided as 80 versus 45, 14, and 8 kPa. In data divided as 80 and 45 versus 14 and 8 kPa, the methods were equal (p = 0.959 and p = 1.000, respectively). Strain ratios were superior (p = 0.030), whereas strain histograms were not significantly better (p = 0.083) than shear-wave elastography in data divided as 80, 45, and 14 versus 8 kPa. Target diameter had an effect on all three methods (p = 0.001). Depth had an effect on shear-wave velocity (p = 0.001). CONCLUSION. The ability to discern different target stiffnesses varies between shear-wave and strain elastography. Target diameter affected all methods. Shear-wave elastography is affected by target depth.

  11. System for robot-assisted real-time laparoscopic ultrasound elastography

    Science.gov (United States)

    Billings, Seth; Deshmukh, Nishikant; Kang, Hyun Jae; Taylor, Russell; Boctor, Emad M.

    2012-02-01

    Surgical robots provide many advantages for surgery, including minimal invasiveness, precise motion, high dexterity, and crisp stereovision. One limitation of current robotic procedures, compared to open surgery, is the loss of haptic information for such purposes as palpation, which can be very important in minimally invasive tumor resection. Numerous studies have reported the use of real-time ultrasound elastography, in conjunction with conventional B-mode ultrasound, to differentiate malignant from benign lesions. Several groups (including our own) have reported integration of ultrasound with the da Vinci robot, and ultrasound elastography is a very promising image guidance method for robotassisted procedures that will further enable the role of robots in interventions where precise knowledge of sub-surface anatomical features is crucial. We present a novel robot-assisted real-time ultrasound elastography system for minimally invasive robot-assisted interventions. Our system combines a da Vinci surgical robot with a non-clinical experimental software interface, a robotically articulated laparoscopic ultrasound probe, and our GPU-based elastography system. Elasticity and B-mode ultrasound images are displayed as picture-in-picture overlays in the da Vinci console. Our system minimizes dependence on human performance factors by incorporating computer-assisted motion control that automatically generates the tissue palpation required for elastography imaging, while leaving high-level control in the hands of the user. In addition to ensuring consistent strain imaging, the elastography assistance mode avoids the cognitive burden of tedious manual palpation. Preliminary tests of the system with an elasticity phantom demonstrate the ability to differentiate simulated lesions of varied stiffness and to clearly delineate lesion boundaries.

  12. Central venous catheters: incidence and predictive factors of venous thrombosis.

    Science.gov (United States)

    Hammes, Mary; Desai, Amishi; Pasupneti, Shravani; Kress, John; Funaki, Brian; Watson, Sydeaka; Herlitz, Jean; Hines, Jane

    2015-07-01

    Central venous catheter access in an acute setting can be a challenge given underlying disease and risk for venous thrombosis. Peripherally inserted central venous catheters (PICCs) are commonly placed but limit sites for fistula creation in patients with chronic renal failure (CKD). The aim of this study is to determine the incidence of venous thrombosis from small bore internal jugular (SBIJ) and PICC line placement. This investigation identifies populations of patients who may not be ideal candidates for a PICC and highlights the importance of peripheral vein preservation in patients with renal failure. A venous Doppler ultrasound was performed at the time of SBIJ insertion and removal to evaluate for thrombosis in the internal jugular vein. Data was collected pre- and post-intervention to ascertain if increased vein preservation knowledge amongst the healthcare team led to less use of PICCs. Demographic factors were collected in the SBIJ and PICC groups and risk factor analysis was completed. 1,122 subjects had PICC placement and 23 had SBIJ placement. The incidence of thrombosis in the PICC group was 10%. One patient with an SBIJ had evidence of central vein thrombosis when the catheter was removed. Univariate and multivariate analysis demonstrated a history of transplant, and the indication of total parenteral nutrition was associated with thrombosis (p<0.001). The decrease in PICCs placed in patients with CKD 6 months before and after intervention was significant (p<0.05). There are subsets of patients ith high risk for thrombosis who may not be ideal candidates for a PICC.

  13. Discrimination of Nonalcoholic Steatohepatitis Using Transient Elastography in Patients with Nonalcoholic Fatty Liver Disease

    Science.gov (United States)

    Kim, Seung Up; Jang, Jae Young; Park, Hana; Kim, Ja Kyung; Lee, Chun Kyon; Chon, Young Eun; Han, Kwang-Hyub

    2016-01-01

    Background/aims The accuracy of noninvasive markers to discriminate nonalcoholic steatohepatitis (NASH) is unsatisfactory. We investigated whether transient elastography (TE) could discriminate patients with NASH from those with nonalcoholic fatty liver disease (NAFLD). Methods The patients suspected of NAFLD who underwent liver biopsy and concomitant TE were recruited from five tertiary centers between November 2011 and December 2013. Results The study population (n = 183) exhibited a mean age of 40.6 years and male predominance (n = 111, 60.7%). Of the study participants, 89 (48.6%) had non-NASH and 94 (51.4%) had NASH. The controlled attenuation parameter (CAP) and liver stiffness (LS) were significantly correlated with the degrees of steatosis (r = 0.656, PCAP>250 dB/m; P = 0.013, OR 3.399, 95% CI 1.295–8.291 for LS>7.0 kPa; and P60 IU/L], we developed a novel CLA model for discriminating patients with NASH. The CLA model showed good discriminatory capability, with an area under the receiver operating characteristic curve (AUROC) of 0.812 (95% CI 0.724–0.880). To assess discriminatory power, the AUROCs, as determined by the bootstrap method, remained largely unchanged between iterations, with an average value of 0.833 (95% CI 0.740–0.893). Conclusion This novel TE-based CLA model showed acceptable accuracy in discriminating NASH from simple steatosis. However, further studies are required for external validation. PMID:27284700

  14. Quantitative evaluation of atrial radio frequency ablation using intracardiac shear-wave elastography.

    Science.gov (United States)

    Kwiecinski, Wojciech; Provost, Jean; Dubois, Rémi; Sacher, Frédéric; Haïssaguerre, Michel; Legros, Mathieu; Nguyen-Dinh, An; Dufait, Rémi; Tanter, Mickaël; Pernot, Mathieu

    2014-11-01

    Radio frequency catheter ablation (RFCA) is a well-established clinical procedure for the treatment of atrial fibrillation (AF) but suffers from a low single-procedure success rate. Recurrence of AF is most likely attributable to discontinuous or nontransmural ablation lesions. Yet, despite this urgent clinical need, there is no clinically available imaging modality that can reliably map the lesion transmural extent in real time. In this study, the authors demonstrated the feasibility of shear-wave elastography (SWE) to map quantitatively the stiffness of RFCA-induced thermal lesions in cardiac tissues in vitro and in vivo using an intracardiac transducer array. SWE was first validated in ex vivo porcine ventricular samples (N = 5). Both B-mode imaging and SWE were performed on normal cardiac tissue before and after RFCA. Areas of the lesions were determined by tissue color change with gross pathology and compared against the SWE stiffness maps. SWE was then performed in vivo in three sheep (N = 3). First, the stiffness of normal atrial tissues was assessed quantitatively as well as its variation during the cardiac cycle. SWE was then performed in atrial tissue after RFCA. A large increase in stiffness was observed in ablated ex vivo regions (average shear modulus across samples in normal tissue: 22 ± 5 kPa, average shear-wave speed (ct): 4.5 ± 0.4 m s(-1) and in determined ablated zones: 99 ± 17 kPa, average ct: 9.0 ± 0.5 m s(-1) for a mean shear modulus increase ratio of 4.5 ± 0.9). In vivo, a threefold increase of the shear modulus was measured in the ablated regions, and the lesion extension was clearly visible on the stiffness maps. By its quantitative and real-time capabilities, Intracardiac SWE is a promising intraoperative imaging technique for the evaluation of thermal ablation during RFCA.

  15. Strain estimation in elastography using scale-invariant keypoints tracking.

    Science.gov (United States)

    Xiao, Yang; Shen, Yang; Niu, Lili; Ling, Tao; Wang, Congzhi; Zheng, Hairong

    2013-04-01

    This paper proposes a novel strain estimator using scale-invariant keypoints tracking (SIKT) for ultrasonic elastography. This method is based on tracking stable features between the pre- and post-compression A-lines to obtain tissue displacement estimates. The proposed features, termed scaleinvariant keypoints, are independent of signal scale change according to the scale-space theory, and therefore can preserve their patterns while undergoing a substantial range of compression. The keypoints can be produced by searching for repeatedly assigned points across all possible scales constructed from the convolution with a one-parameter family of Gaussian kernels. Because of the distinctive property of the keypoints, the SIKT method could provide a reliable tracking over changing strains, an effective resistance to anamorphic noise and sonographic noise, and a significant reduction in processing time. Simulation and experimental results show that the SIKT method is able to provide better sensitivity, a larger dynamic range of the strain filter, higher resolution, and a better contrast- to-noise ratio (CNRe) than the conventional methods. Moreover, the computation time of the SIKT method is approximately 5 times that of the cross-correlation techniques.

  16. Tissue characterization using magnetic resonance elastography: preliminary results*

    Science.gov (United States)

    Kruse, S. A.; Smith, J. A.; Lawrence, A. J.; Dresner, M. A.; Manduca, A.; Greenleaf, J. F.; Ehman, R. L.; Kruse, S. A.; Smith, J. A.; Lawrence, A. J.; Dresner, M. A.; Manduca, A.; Greenleaf, J. F.

    2000-06-01

    The well-documented effectiveness of palpation as a diagnostic technique for detecting cancer and other diseases has provided motivation for developing imaging techniques for non-invasively evaluating the mechanical properties of tissue. A recently described approach for elasticity imaging, using propagating acoustic shear waves and phase-contrast MRI, has been called magnetic resonance elastography (MRE). The purpose of this work was to conduct preliminary studies to define methods for using MRE as a tool for addressing the paucity of quantitative tissue mechanical property data in the literature. Fresh animal liver and kidney tissue specimens were evaluated with MRE at multiple shear wave frequencies. The influence of specimen temperature and orientation on measurements of stiffness was studied in skeletal muscle. The results demonstrated that all of the materials tested (liver, kidney, muscle and tissue-simulating gel) exhibit systematic dependence of shear stiffness on shear rate. These data are consistent with a viscoelastic model of tissue mechanical properties, allowing calculation of two independent tissue properties from multiple-frequency MRE data: shear modulus and shear viscosity. The shear stiffness of tissue can be substantially affected by specimen temperature. The results also demonstrated evidence of shear anisotropy in skeletal muscle but not liver tissue. The measured shear stiffness in skeletal muscle was found to depend on both the direction of propagation and polarization of the shear waves.

  17. Magnetomotive optical coherence elastography for microrheology of biological tissues

    Science.gov (United States)

    Crecea, Vasilica; Ahmad, Adeel; Boppart, Stephen A.

    2013-12-01

    Optical coherence elastography (OCE) is an established paradigm for measuring biomechanical properties of tissues and cells noninvasively, in real time, and with high resolution. We present a different development of a spectral domain OCE technique that enables simultaneous measurements of multiple biomechanical parameters of biological tissues. Our approach extends the capabilities of magnetomotive OCE (MM-OCE), which utilizes iron oxide magnetic nanoparticles (MNPs) distributed and embedded in the specimens as transducers for inducing motion. Step-wise application of an external magnetic field results in displacements in the tissue specimens that are deduced from sensitive phase measurements made with the MM-OCE system. We analyzed freshly excised rabbit lung and muscle tissues. We observe that while they present some similarities, rabbit lung and muscle tissue displacements display characteristic differentiating features. Both tissue types undergo a fast initial displacement followed by a rapidly damped oscillation and the onset of creep. However, the damping is faster in muscle compared to lung tissue, while the creep is steeper in muscle. This approach has the potential to become a novel way of performing real-time measurements of biomechanical properties of tissues and to enable the development of different diagnostic and monitoring tools in biology and medicine.

  18. Method for optical coherence elastography of the cornea

    Science.gov (United States)

    Ford, Matthew R.; Dupps, William J.; Rollins, Andrew M.; Roy, Abhijit Sinha; Hu, Zhilin

    2011-01-01

    The material properties of the cornea are important determinants of corneal shape and refractive power. Corneal ectatic diseases, such as keratoconus, are characterized by material property abnormalities, are associated with progressive thinning and distortion of the cornea, and represent a leading indication for corneal transplantation. We describe a corneal elastography technique based on optical coherence tomography (OCT) imaging, in which displacement of intracorneal optical features is tracked with a 2-D cross-correlation algorithm as a step toward nondestructive estimation of local and directional corneal material properties. Phantom experiments are performed to measure the effects of image noise and out-of-plane displacement on effectiveness of displacement tracking and demonstrated accuracy within the tolerance of a micromechanical translation stage. Tissue experiments demonstrate the ability to produce 2-D maps of heterogeneous intracorneal displacement with OCT. The ability of a nondestructive optical method to assess tissue under in situ mechanical conditions with physiologic-range stress levels provides a framework for in vivo quantification of 3-D corneal elastic and viscoelastic resistance, including analogs of shear deformation and Poisson's ratio that may be relevant in the early diagnosis of corneal ectatic disease.

  19. Shear-Wave Elastography: Basic Physics and Musculoskeletal Applications.

    Science.gov (United States)

    Taljanovic, Mihra S; Gimber, Lana H; Becker, Giles W; Latt, L Daniel; Klauser, Andrea S; Melville, David M; Gao, Liang; Witte, Russell S

    2017-01-01

    In the past 2 decades, sonoelastography has been progressively used as a tool to help evaluate soft-tissue elasticity and add to information obtained with conventional gray-scale and Doppler ultrasonographic techniques. Recently introduced on clinical scanners, shear-wave elastography (SWE) is considered to be more objective, quantitative, and reproducible than compression sonoelastography with increasing applications to the musculoskeletal system. SWE uses an acoustic radiation force pulse sequence to generate shear waves, which propagate perpendicular to the ultrasound beam, causing transient displacements. The distribution of shear-wave velocities at each pixel is directly related to the shear modulus, an absolute measure of the tissue's elastic properties. Shear-wave images are automatically coregistered with standard B-mode images to provide quantitative color elastograms with anatomic specificity. Shear waves propagate faster through stiffer contracted tissue, as well as along the long axis of tendon and muscle. SWE has a promising role in determining the severity of disease and treatment follow-up of various musculoskeletal tissues including tendons, muscles, nerves, and ligaments. This article describes the basic ultrasound physics of SWE and its applications in the evaluation of various traumatic and pathologic conditions of the musculoskeletal system. ©RSNA, 2017.

  20. Influence of corneal hydration on optical coherence elastography

    Science.gov (United States)

    Twa, Michael D.; Vantipalli, Srilatha; Singh, Manmohan; Li, Jiasong; Larin, Kirill V.

    2016-03-01

    Corneal biomechanical properties are influenced by several factors, including intraocular pressure, corneal thickness, and viscoelastic responses. Corneal thickness is directly proportional to tissue hydration and can influence corneal stiffness, but there is no consensus on the magnitude or direction of this effect. We evaluated the influence of corneal hydration on dynamic surface deformation responses using optical coherence elastography (OCE). Fresh rabbit eyes (n=10) were prepared by removing the corneal epithelium and dropping with 0.9% saline every 5 minutes for 1 hour, followed by 20% dextran solution every 5 minutes for one hour. Corneal thickness was determined from structural OCT imaging and OCE measurements were performed at baseline and every 20 minutes thereafter. Micron-scale deformations were induced at the apex of the corneal tissue using a spatially-focused (150μm) short-duration (corneal thickness due to hydration process. Corneal thickness rapidly increased and remained constant following epithelium removal and changed little thereafter. Likewise, corneal stiffness changed little over the first hour and then decreased sharply after Dextran application (thickness: -46% [-315/682 μm] RR: - 24% [-0.7/2.88 ms-1]; GV: -19% [-0.6/3.2 m/s]). Corneal thickness and corneal stiffness (RR) were well correlated (R2 = .66). Corneal biomechanical properties are highly correlated with tissue hydration over a wide range of corneal thickness and these changes in corneal stiffness are quantifiable using OCE.

  1. Development and clinical application of transient elastography(FibroScan

    Directory of Open Access Journals (Sweden)

    Guo-feng CHEN

    2011-11-01

    Full Text Available Chronic liver fibrosis,an important step in the development of liver diseases,is an anaplerotic reaction of an organism to chronic liver damage caused by various kinds of pathogens.It is a common pathologic change in chronic liver diseases and the intermediate link in the development of liver cirrhosis.Liver fibrosis can be reversed in the early stage,as well as in the later stage.Cases of liver cirrhosis that are confirmed during the earlier stage can be treated and prognosticated more efficiently.Currently,liver biopsy is still the gold standard for diagnosing liver fibrosis.However,its invasiveness causes patients to refuse the examination.Noninvasive diagnostic technology for liver fibrosis has made considerable development in recent years.One of these technologies is transient elastography(FibroScan of liver stiffness using elastic shear wave,which has good accuracy and specificity for the determination of liver fibrosis.It is noninvasive,fast,repeatable,and it can evaluate liver fibrosis objectively and quantitatively.It will have a broad range of clinical applications in the future.

  2. Elastography using harmonic ultrasonic imaging: a feasibility study.

    Science.gov (United States)

    Desai, Raghavendra Reddy; Krouskop, Thomas A; Righetti, Raffaella

    2010-04-01

    Tissue Harmonic Imaging (THI) is a relatively new modality that has had a significant impact in the ultrasound field. In the recent past, imaging the mechanical properties of tissues using elastography has also gained great interest. In this paper, we investigate the feasibility of combining these two state-of-the-art ultrasound-imaging modalities. The performance of elastograms obtained using harmonic ultrasonic signals is studied with simulations and compared to the performance of conventional elastograms using standard statistical methods. Experiments are used as a proof of the technical feasibility of generating tissue-harmonic elastograms using experimental harmonic signals. The results of our simulation study indicate that all image quality factors considered in this study (elastographic signal-to-noise ratio, elastographic contrast-to-noise ratio and spatial resolution) may be improved when using harmonic ultrasonic signals, provided that the ultrasound system is characterized by high bandwidth, high sampling frequency and large lateral sampling. Preliminary experimental results suggest that it is technically feasible to generate experimental elastograms using harmonic signals, provided that the sonographic signal-to-noise ratio of the pre- and postcompression harmonic frames is sufficiently high to guarantee reliable values of correlation.

  3. Maximum likelihood estimation of shear wave speed in transient elastography.

    Science.gov (United States)

    Audière, Stéphane; Angelini, Elsa D; Sandrin, Laurent; Charbit, Maurice

    2014-06-01

    Ultrasonic transient elastography (TE), enables to assess, under active mechanical constraints, the elasticity of the liver, which correlates with hepatic fibrosis stages. This technique is routinely used in clinical practice to assess noninvasively liver stiffness. The Fibroscan system used in this work generates a shear wave via an impulse stress applied on the surface of the skin and records a temporal series of radio-frequency (RF) lines using a single-element ultrasound probe. A shear wave propagation map (SWPM) is generated as a 2-D map of the displacements along depth and time, derived from the correlations of the sequential 1-D RF lines, assuming that the direction of propagation (DOP) of the shear wave coincides with the ultrasound beam axis (UBA). Under the assumption of pure elastic tissue, elasticity is proportional to the shear wave speed. This paper introduces a novel approach to the processing of the SWPM, deriving the maximum likelihood estimate of the shear wave speed when comparing the observed displacements and the estimates provided by the Green's functions. A simple parametric model is used to interface Green's theoretical values of noisy measures provided by the SWPM, taking into account depth-varying attenuation and time-delay. The proposed method was evaluated on numerical simulations using a finite element method simulator and on physical phantoms. Evaluation on this test database reported very high agreements of shear wave speed measures when DOP and UBA coincide.

  4. [Assessment of plantar fasciitis using shear wave elastography].

    Science.gov (United States)

    Zhang, Lining; Wan, Wenbo; Zhang, Lihai; Xiao, Hongyu; Luo, Yukun; Fei, Xiang; Zheng, Zhixin; Tang, Peifu

    2014-02-01

    To assess the stiffness and thickness of the plantar fascia using shear wave elastography (SWE) in healthy volunteers of different ages and in patients with plantar fasciitis. The bilateral feet of 30 healthy volunteers and 23 patients with plantar fasciitis were examined with SWE. The plantar fascia thickness and elasticity modulus value were measured at the insertion of the calcaneus and at 1 cm from the insertion. The elderly volunteers had a significantly greater plantar fascia thickness measured using conventional ultrasound (P=0.005) and a significantly lower elasticity modulus value than the young volunteers (P=0.000). The patients with fasciitis had a significantly greater plantar fascia thickness (P=0.001) and a lower elasticity modulus value than the elderly volunteers (P=0.000). The elasticity modulus value was significantly lower at the calcaneus insertion than at 1 cm from the insertion in patients with fasciitis (P=0.000) but showed no significantly difference between the two points in the elderly or young volunteers (P=0.172, P=0.126). SWE allows quantitative assessment of the stiffness of the plantar fascia, which decreases with aging and in patients with plantar fasciitis.

  5. Ultrasound elastography assessment of bone/soft tissue interface

    Science.gov (United States)

    Parmar, Biren J.; Yang, Xu; Chaudhry, Anuj; Shafeeq Shajudeen, Peer; Nair, Sanjay P.; Weiner, Bradley K.; Tasciotti, Ennio; Krouskop, Thomas A.; Righetti, Raffaella

    2016-01-01

    We report on the use of elastographic imaging techniques to assess the bone/soft tissue interface, a region that has not been previously investigated but may provide important information about fracture and bone healing. The performance of axial strain elastograms and axial shear strain elastograms at the bone/soft tissue interface was studied ex vivo on intact and fractured canine and ovine tibias. Selected ex vivo results were corroborated on intact sheep tibias in vivo. The elastography results were statistically analyzed using elastographic image quality tools. The results of this study demonstrate distinct patterns in the distribution of the normalized local axial strains and axial shear strains at the bone/soft tissue interface with respect to the background soft tissue. They also show that the relative strength and distribution of the elastographic parameters change in the presence of a fracture and depend on the degree of misalignment between the fracture fragments. Thus, elastographic imaging modalities might be used in the future to obtain information regarding the integrity of bones and to assess the severity of fractures, alignment of bone fragments as well as to follow bone healing.

  6. Shear wave elastography findings of de Quervain tenosynovitis.

    Science.gov (United States)

    Turkay, Rustu; Inci, Ercan; Aydeniz, Banu; Vural, Meltem

    2017-10-01

    Our aim was to evaluate the feasibility of using shear wave elastography (SWE) to assess first extensor compartment tendons rigidity and its alterations with tenosynovitis. We performed B-mode ultrasound and SWE to total number of 80 participants. All participants were evaluated clinically to call the diagnosis of de Quervain tenosynovitis or to rule out the diagnosis. We composed 2 groups. Group 1 included 40 healthy volunteers (33 females and 7 male participants with ages ranging from 24 to 60 years, median age was 37.5 years) and group 2 had 40 de Quervain patients (32 females and 8 male patients with ages ranging from 25 to 51 years, median age was 34 years). SWE measurements were repeated 3 times and arithmetic average was used for the final SWE value. The median SWE value of healthy group (group 1) was 72kPa and the de Quervain patient group (group 2) was 29kPa. Two groups demonstrated statistically significant difference (p<0.001). The ROC curve analysis was performed and the SWE value of 40.5kPA was calculated as a cut-off value for the diagnosis of de Quervain tenosynovitis with 95% specificity and 85% sensitivity. SWE modality can provide useful data regarding de Quervain tenosynovitis. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Interventional MR elastography for MRI-guided percutaneous procedures.

    Science.gov (United States)

    Corbin, Nadège; Vappou, Jonathan; Breton, Elodie; Boehler, Quentin; Barbé, Laurent; Renaud, Pierre; de Mathelin, Michel

    2016-03-01

    MRI-guided thermal ablations require reliable monitoring methods to ensure complete destruction of the diseased tissue while avoiding damage to the surrounding healthy tissue. Based on the fact that thermal ablations result in substantial changes in biomechanical properties, interventional MR elastography (MRE) dedicated to the monitoring of MR-guided thermal therapies is proposed here. Interventional MRE consists of a needle MRE driver, a fast and interactive gradient echo pulse sequence with motion encoding, and an inverse problem solver in real-time. This complete protocol was tested in vivo on swine and the ability to monitor elasticity changes in real-time was assessed in phantom. Thanks to a short repetition time, a reduction of the number of phase-offsets and the use of a sliding window, one refreshed elastogram was provided every 2.56 s for an excitation frequency of 100 Hz. In vivo elastograms of swine liver were successfully provided in real-time during one breath-hold. Changes of elasticity were successfully monitored in a phantom during its gelation with the same elastogram frame rate. This study demonstrates the ability of detecting elasticity changes in real-time and providing elastograms in vivo with interventional MRE that could be used for the monitoring of thermal ablations. © 2015 Wiley Periodicals, Inc.

  8. Non-invasive high-frequency vascular ultrasound elastography

    Energy Technology Data Exchange (ETDEWEB)

    Maurice, Roch L [Laboratory of Biorheology and Medical Ultrasonics, Research Center, University of Montreal Hospital, Quebec (Canada); Daronat, Michel [Laboratory of Biorheology and Medical Ultrasonics, Research Center, University of Montreal Hospital, Quebec (Canada); Ohayon, Jacques [Laboratory TIMC-IMAG, UMR CNRS 5525, Institut A. Bonniot, 38706 La Tronche (France); Stoyanova, Ekatherina [Laboratory of Biorheology and Medical Ultrasonics, Research Center, University of Montreal Hospital, Quebec (Canada); Foster, F Stuart [Department of Medical Biophysics, Sunnybrook and Women' s College Health Sciences Centre, University of Toronto, Ontario (Canada); Cloutier, Guy [Laboratory of Biorheology and Medical Ultrasonics, Research Center, University of Montreal Hospital, Quebec (Canada); Department of Radiology, Radio-oncology and Nuclear Medicine, University of Montreal, Quebec (Canada)

    2005-04-07

    Non-invasive vascular elastography (NIVE) was recently introduced to characterize mechanical properties of superficial arteries. In this paper, the feasibility of NIVE and its applicability in the context of high-frequency ultrasound imaging is investigated. First, experiments were performed in vitro on vessel-mimicking phantoms. Polyvinyl alcohol cryogel was used to create two double-layer vessels with different mechanical properties. In both cases, the stiffness of the inner layer was made softer. Radial stress was applied within the lumen of the phantoms by applying incremental static pressure steps with a column of a flowing mixture of water-glycerol. The vessel phantoms were insonified at 32 MHz with an ultrasound biomicroscope to provide cross-section sequences of radio-frequency (RF) ultrasound data. The Lagrangian speckle model estimator (LSME) was used to assess the two-dimensional-strain tensors, and the composite Von Mises elastograms were computed. A new implementation of the LSME based on the optical flow equations was introduced. Deformation parameters were estimated using an inversion algorithm. For each in vitro experiment, both layers of approximately 1 mm were distinguished. Second, the use of the method for the purpose of studying small vessels (MicroNIVE) in genetically engineered rodents was introduced. Longitudinal scans of the carotid artery were performed at 40 MHz. The in vivo results give confidence in the feasibility of MicroNIVE as a potential tool to non-invasively study the impact of targeted genes on vascular remodelling in rodents.

  9. Hormonal contraceptives and venous thrombosis

    NARCIS (Netherlands)

    Stegeman, Berendina Hendrika (Bernardine)

    2013-01-01

    Oral contraceptive use is associated with venous thrombosis. However, the mechanism behind this remains unclear. The aim of this thesis was to evaluate genetic variation in the first-pass metabolism of contraceptives, to identify the clinical implications of hormonal contraceptive use after a

  10. Lower-limb venous thrombosis

    African Journals Online (AJOL)

    307. Lower-limb venous thrombosis. July 2009 Vol.27 No.7 CME. Most DVTs arise in calf muscle veins, particularly within the gastrocnemius and soleus muscles (calf vein DVT). Many of these remain localised to the muscle and will not cause any clinical problem. If, however, the circumstances that initially caused the.

  11. Comparison of Ultrasound Elastography and Color Doppler Ultrasonography for Distinguishing Small Triple-Negative Breast Cancer From Fibroadenoma.

    Science.gov (United States)

    Yeo, Soo Hyun; Kim, Ga Ram; Lee, Su Hyun; Moon, Woo Kyung

    2018-02-09

    To compare the performance of ultrasound elastography and color Doppler ultrasonography (US) in distinguishing small, oval, or round triple-negative breast cancer from fibroadenoma and the influence on the further management decision at US. In total, 131 biopsy-proven oval or round fibroadenomas (n = 68) and triple-negative breast cancers (n = 63) smaller than 2 cm were included. Three blinded readers assessed the images from US, elastography, and color Doppler imaging according to the Breast Imaging Reporting and Data System lexicon independently. Interobserver agreement was assessed, and sensitivity, specificity, accuracy, and area under the receiver operating characteristic curve values for each data set were compared. Pathologic results were reference standards. The interobserver agreements were excellent (intraclass correlation coefficients, 0.856 for US, 0.948 for elastography, and 0.864 for color Doppler). The specificity and accuracy of US with elastography were increased compared with US alone or US with Doppler imaging without statistically significant differences in sensitivity. The average area under the curve for US with elastography (0.869) was increased compared with US alone (0.650) or US with color Doppler (0.576). Elastography is more useful than color Doppler imaging for distinguishing small, oval, or round triple-negative breast cancer from fibroadenoma, and elastography can help avoid biopsy of benign masses. © 2018 by the American Institute of Ultrasound in Medicine.

  12. Increased rheumatoid factor and deep venous thrombosis

    DEFF Research Database (Denmark)

    Meyer-Olesen, Christine L; Nielsen, Sune F; Nordestgaard, Børge G

    2015-01-01

    BACKGROUND: The risk of deep venous thrombosis is increased in patients with rheumatoid arthritis. We tested the hypothesis that increased concentrations of rheumatoid factor are associated with increased risk of deep venous thrombosis in individuals without autoimmune rheumatic disease in the ge......BACKGROUND: The risk of deep venous thrombosis is increased in patients with rheumatoid arthritis. We tested the hypothesis that increased concentrations of rheumatoid factor are associated with increased risk of deep venous thrombosis in individuals without autoimmune rheumatic disease...... in the general population. METHODS: We included 54628 participants from the Copenhagen City Heart Study (1981-83) and the Copenhagen General Population Study (2004-12), all with a measured concentration of IgM rheumatoid factor and without autoimmune rheumatic disease or venous thromboembolism. The main outcome...... was incident deep venous thrombosis. There were no losses to follow-up. RESULTS: During 368381 person-years, 670 individuals developed deep venous thrombosis. A rheumatoid factor concentration ≥ vs

  13. Radiologically-placed venous ports in children under venous anesthesia

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Joo Yeon; Jeon, Ung Bae; Choo, Ki Seok; Hwang, Jae Yeon; Kim, Yong Woo; Lee, Yun Jin; Nam, Sang Ool; Lim, Young Tak [Pusan National University School of Medicine, Yangsan (Korea, Republic of)

    2015-02-15

    To evaluate the efficacy and safety of radiologic venous port placement in children under venous anesthesia. Between April 2009 and July 2011, 44 ports were implanted in 41 children (24 boys, 17 girls). The age of patients ranged from 9 months to 19 years (mean, 6.5 years) and their body weights ranged from 6.8 kg to 56.3 kg (mean, 23.2 kg). Right internal jugular vein access was used in 42 ports, right subclavian vein in 1, and left subclavian in 1. Durability and complications of port implantation were reviewed. The technical success rate was 100%. The catheter life was 10-661 days (mean 246 days). Two patients died during the follow-up period, 21 and 6 ports were removed at the end of treatment or as a result of complications, respectively. One port was removed and replaced by a Hickmann catheter. Three ports were explanted due to port-related sepsis, one due to a catheter kink, and two for unexplained fever or insertion site pain. The overall port-related infection was 3 cases (6.8%, 0.28/1000 catheter days). Venous port placement by interventional radiologists in children under intravenous sedation is relatively safe, with a high rate of technical success and low rate of complications.

  14. Iliac venous pressure estimates central venous pressure after laparotomy.

    Science.gov (United States)

    Boone, Brian A; Kirk, Katherine A; Tucker, Nikia; Gunn, Scott; Forsythe, Raquel

    2014-09-01

    Central venous pressure (CVP) is traditionally obtained through subclavian or internal jugular central catheters; however, many patients who could benefit from CVP monitoring have only femoral lines. The accuracy of illiac venous pressure (IVP) as a measure of CVP is unknown, particularly following laparotomy. This was a prospective, observational study. Patients who had both internal jugular or subclavian lines and femoral lines already in place were eligible for the study. Pressure measurements were taken from both lines in addition to measurement of bladder pressure, mean arterial pressure, and peak airway pressure. Data were evaluated using paired t-test, Bland-Altman analysis, and linear regression. Measurements were obtained from 40 patients, 26 of which had laparotomy. The mean difference between measurements was 2.2 mm Hg. There were no significant differences between patients who had laparotomy and nonsurgical patients (P = 0.93). Bland-Altman analysis revealed a bias of 1.63 ± 2.44 mm Hg. There was no correlation between IVP accuracy and bladder pressure, mean arterial pressure, or peak airway pressure. IVP is an adequate measure of CVP, even in surgical patients who have had recent laparotomy. Measurement of IVP to guide resuscitation is encouraged in patients who have only femoral venous catheter access. Copyright © 2014. Published by Elsevier Inc.

  15. Optical coherence elastography for measuring the deformation within glass fiber composite

    NARCIS (Netherlands)

    Liu, P.; Groves, R.M.; Benedictus, R.

    2014-01-01

    Optical coherence elastography (OCE) has been applied to the study of microscopic deformation in biological tissue under compressive stress for more than a decade. In this paper, OCE has been extended for the first time, to the best of our knowledge, to deformation measurement in a glass fiber

  16. Comparison of interobserver agreement of magnetic resonance elastography with histopathological staging of liver fibrosis

    NARCIS (Netherlands)

    Runge, Jurgen H.; Bohte, Anneloes E.; Verheij, Joanne; Terpstra, Valeska; Nederveen, Aart J.; van Nieuwkerk, Karin M. J.; de Knegt, Rob J.; Baak, Bert C.; Jansen, Peter L. M.; Sinkus, Ralph; Stoker, Jaap

    2014-01-01

    MR elastography (MRE) can serve as an accurate surrogate marker of liver fibrosis. For any diagnostic test that is to replace the current reference standard, interobserver agreement should be at least as good and preferably better. The objective of this study was to perform a head-to-head comparison

  17. Acoustic radiation force impulse (ARFI elastography of adrenal glands in healthy adult dogs

    Directory of Open Access Journals (Sweden)

    S. Fernandez

    Full Text Available ABSTRACT To describe the ARFI elastography in the evaluation of the adrenal glands in adult dogs, to evaluate the stiffness of adrenal parenchyma and to determine the qualitative and quantitative standards of the ARFI technique, which have not yet been described in veterinary medicine. Sixty adrenal glands from thirty healthy adult dogs were evaluated by B-mode and qualitative and quantitative ARFI elastography to assess the stiffness of healthy parenchyma and to determine the quality and quantity (shear velocity standards of ARFI technique in body, cranial and caudal adrenal poles. Findings of ultrasonography evaluations were normal. Qualitative elastography showed that adrenal glands were not deformable and presented homogeneous middle-gray areas. The results of shear wave velocity were similar statically (P = 0.3087: 1 left adrenal - 1.42 m/s for cranial polar, 1.31 m/s for body region, and 1.71 m/s for caudal polar; 2 right adrenal - 1.42 m/s for cranial polar, 1.74 m/s for body region and 1.63 m/s for caudal pole. Quantitative and qualitative ARFI elastography of dogs' adrenal glands is feasible, well tolerated, easily implemented and may provide baseline data in the study of this structure to allow the use of ARFI.

  18. Measurement of muscle architecture concurrently with muscle hardness using ultrasound strain elastography.

    Science.gov (United States)

    Chino, Kentaro; Akagi, Ryota; Dohi, Michiko; Takahashi, Hideyuki

    2014-09-01

    The B-mode ultrasound image that can measure muscle architecture is displayed side by side with the ultrasound strain elastogram that can assess muscle hardness. Consequently, muscle architecture can be measured concurrently with muscle hardness using ultrasound strain elastography. To demonstrate the measurement of muscle architecture concurrently with muscle hardness using ultrasound strain elastography. Concurrent measurements of muscle architectural parameters (muscle thickness, pennation angle, and fascicle length) and muscle hardness of the medial gastrocnemius were performed with ultrasound strain elastography. Separate measurements of the muscle architectural parameters were also performed for use as reference values for the concurrent measurements. Both types of measurements were performed twice at 20° dorsiflexion, neutral position, and 30° plantar flexion. Coefficients of variance of the muscle architectural parameters obtained from the concurrent measurements (≤7.6%) were significantly higher than those obtained from the separate measurements (≤2.4%) (all P  0.05). The use of ultrasound strain elastography for the concurrent measurement of muscle architecture and muscle hardness is feasible. © The Foundation Acta Radiologica 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  19. Assessment of biopsy-proven liver fibrosis by 2D-shear wave elastography

    DEFF Research Database (Denmark)

    Herrmann, Eva; de Lédinghen, Victor; Cassinotto, Christophe

    2017-01-01

    BACKGROUND AND AIMS: 2D shear wave elastography (2D-SWE) has proven to be efficient for the evaluation of liver fibrosis in small to moderate size clinical trials. We aimed at running a larger scale meta-analysis of individual data. METHODS: Centers which have worked with Aixplorer ultrasound equ...

  20. Differential diagnosis of thyroid nodules with US elastography using carotid artery pulsation.

    Science.gov (United States)

    Dighe, Manjiri; Bae, Unmin; Richardson, Michael L; Dubinsky, Theodore J; Minoshima, Satoshi; Kim, Yongmin

    2008-08-01

    To explore the sensitivity and specificity of ultrasonographic (US) elastography using carotid arterial pulsation as the compression source for differential diagnosis of thyroid nodules. This HIPAA-compliant study was approved by the ethics committee of the institution, and all patients provided written informed consent. Fifty-eight patients (13 men and 45 women [mean age, 51 years; range, 20-76 years]) were enrolled. A short US examination and elastography with pulsation of the carotid artery used as the thyroid compression source were performed before fine-needle aspiration. Baseband US data were downloaded for off-line analysis. Elastographic maps and the thyroid stiffness index were calculated. The Kruskal-Wallis nonparametric rank sum test was used to assess equality of population medians among the different types of thyroid nodules; the R software environment was used for statistical computing and graphics (http://www.r-project.org/). Thyroid stiffness index calculated with elastography using carotid arterial pulsation as the compression source was effective in helping distinguish between papillary carcinomas (n = 10) and other lesions (n = 43) because papillary carcinomas were stiffer than other lesions (P < .0039). It is possible to distinguish between papillary carcinomas and other lesions with the thyroid stiffness index calculated from US elastography using carotid arterial pulsation.

  1. Cervical ultrasound elastography may hold potential to predict risk of preterm birth

    DEFF Research Database (Denmark)

    Khalil, Mohammed R; Thorsen, Poul; Uldbjerg, Niels

    2013-01-01

    Freehand ultrasound real-time elastography (RTE) is a simple technique allowing direct visualization of the elastogramme superimposed on the B-mode -image. The objective of RTE is to investigate stiffness and related parameters such as local tissue strain with a view to adding new information...

  2. Agreement between a computer-assisted tool and radiologists to classify lesions in breast elastography images

    Science.gov (United States)

    Marcomini, Karem D.; Fleury, Eduardo F. C.; Oliveira, Vilmar M.; Carneiro, Antonio A. O.; Schiabel, Homero; Nishikawa, Robert M.

    2017-03-01

    Breast elastography is a new sonographic technique that provides additional information to evaluate tissue stiffness. However, interpreting breast elastography images can vary depending on the radiologist. In order to provide quantitative and less subjective data regarding the stiffness of a lesion, we developed a tool to measure the amount of hard area in a lesion from the 2D image. The database consisted of 78 patients with 83 breast lesions (31 malignant and 52 benign). Two radiologists and one resident manually drew the contour of the lesions in B-mode ultrasound images and the contour was mapped in the elastography image. By using the system proposed, the radiologists obtained a very good diagnostic agreement among themselves (kappa = 0.86), achieving the same sensitivity and specificity (80.7 and 88.5, respectively), and an AUC of 0.883 for Radiologist 1 and 0.892 for Radiologist 2. The Resident had less interobserver agreement, as well as lower specificity and AUC, which may be related to less experience. Furthermore, the radiologists had an agreement with the tool used in the automatic method higher than 90%. Thus, the method developed was useful in aiding the diagnosis of breast lesions in strain elastography, minimizing its subjectivity.

  3. Ultrasound Elastography: The New Frontier in Direct Measurement of Muscle Stiffness

    Science.gov (United States)

    Brandenburg, Joline E.; Eby, Sarah F.; Song, Pengfei; Zhao, Heng; Brault, Jeffrey S.; Chen, Shigao; An, Kai-Nan

    2014-01-01

    The use of brightness-mode ultrasound and Doppler ultrasound in physical medicine and rehabilitation has increased dramatically. The continuing evolution of ultrasound technology has also produced ultrasound elastography, a cutting-edge technology that can directly measure the mechanical properties of tissue, including muscle stiffness. Its real-time and direct measurements of muscle stiffness can aid the diagnosis and rehabilitation of acute musculoskeletal injuries and chronic myofascial pain. It can also help monitor outcomes of interventions affecting muscle in neuromuscular and musculoskeletal diseases, and it can better inform the functional prognosis. This technology has implications for even broader use of ultrasound in physical medicine and rehabilitation practice, but more knowledge about its uses and limitations is essential to its appropriate clinical implementation. In this review, we describe different ultrasound elastography techniques for studying muscle stiffness, including strain elastography, acoustic radiation force impulse imaging, and shear-wave elastography. We discuss the basic principles of these techniques, including the strengths and limitations of their measurement capabilities. We review the current muscle research, discuss physiatric clinical applications of these techniques, and note directions for future research. PMID:25064780

  4. Clinical Applicability of Transient Elastography for Estimating Liver Stiffness in Patients with Type 2 Diabetes Mellitus

    NARCIS (Netherlands)

    Van Dijk, P. R.; Landman, G. W. D.; Hoving, S.; Kleefstra, N.; Bilo, H. J. G.; Groeneveld, P. H. P.

    2016-01-01

    Background: Type 2 diabetes mellitus (T2DM) is a risk factor for the development of non-alcoholic fatty liver disease, which can lead to liver fibrosis and ultimately to cirrhosis. Transient elastography (TE), by using the FibroScan, and is a non-invasive ultrasonography method to measure liver

  5. Analisys of pectoralis major tendon in weightlifting athletes using ultrasonography and elastography

    Energy Technology Data Exchange (ETDEWEB)

    Pochini, Alberto de Castro [Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP (Brazil); Ferretti, Mario [Hospital Israelita Albert Einstein, São Paulo, SP (Brazil); Kawakami, Eduardo Felipe Kin Ito; Fernandes, Artur da Rocha Corrêa; Yamada, Andre Fukunishi; Oliveira, Gabriela Clemente de; Cohen, Moisés; Andreoli, Carlos Vicente; Ejnisman, Benno [Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP (Brazil)

    2015-07-01

    To evaluate tendinopathy of the pectoralis major muscle in weightlifting athletes using ultrasound and elastography. This study included 20 patients, 10 with rupture of the pectoralis major muscle and 10 control patients. We evaluated pectoralis major muscle contralateral tendon with ultrasonographic and elastography examinations. The ultrasonographic examinations were performed using a high-resolution B mode ultrasound device. The elastography evaluation was classified into three patterns: (A), if stiff (more than 50% area with blue staining); (B), if intermediate (more than 50% green); and (C), if softened (more than 50% red). Patients’ mean age was 33±5.3 years. The presence of tendinous injury measured by ultrasound had a significant different (p=0.0055), because 80% of cases had tendinous injury versus 10% in the Control Group. No significant differences were seen between groups related with change in elastography (p=0.1409). Long-term bodybuilders had ultrasound image with more tendinous injury than those in Control Group. There was no statistical significance regarding change in tendon elasticity compared with Control Group.

  6. Elastography Study of Hamstring Behaviors during Passive Stretching.

    Directory of Open Access Journals (Sweden)

    Guillaume Le Sant

    Full Text Available The mechanical properties of hamstring muscles are usually inferred from global passive torque/angle relationships, in combination with adjoining tissues crossing the joint investigated. Shear modulus measurement provides an estimate of changes in muscle-tendon stiffness and passive tension. This study aimed to assess the passive individual behavior of each hamstring muscle in different stretching positions using shear wave elastography.The muscle shear modulus of each hamstring muscle was measured during a standardized slow passive knee extension (PKE, 80% of maximal range of motion on eighteen healthy male volunteers. Firstly, we assessed the reliability of the measurements. Results were good for semitendinosus (ST, CV: 8.9%-13.4%, semimembranosus (SM, CV: 10.3%-11.2% and biceps femoris long-head (BF-lh, CV: 8.6%-13.3%, but not for biceps femoris short-head (BF-sh, CV: 20.3%-44.9%. Secondly, we investigated each reliable muscle in three stretch positions: 70°, 90° and 110° of hip flexion. The results showed different values of shear modulus for the same amount of perceived stretch, with the highest measurements in the high-flexed hip situation. Moreover, individual muscles displayed different values, with values increasing or BF-lh, SM and ST, respectively. The inter-subject variability was 35.3% for ST, 27.4% for SM and 30.2% for BF-lh.This study showed that the hip needs to be high-flexed to efficiently tension the hamstrings, and reports a higher muscle-tendon stress tolerance at 110° of hip angle. In addition muscles have different passive behaviors, and future works will clarify if it can be linked with rate of injury.

  7. Artificial neural networks for stiffness estimation in magnetic resonance elastography.

    Science.gov (United States)

    Murphy, Matthew C; Manduca, Armando; Trzasko, Joshua D; Glaser, Kevin J; Huston, John; Ehman, Richard L

    2017-11-28

    To investigate the feasibility of using artificial neural networks to estimate stiffness from MR elastography (MRE) data. Artificial neural networks were fit using model-based training patterns to estimate stiffness from images of displacement using a patch size of ∼1 cm in each dimension. These neural network inversions (NNIs) were then evaluated in a set of simulation experiments designed to investigate the effects of wave interference and noise on NNI accuracy. NNI was also tested in vivo, comparing NNI results against currently used methods. In 4 simulation experiments, NNI performed as well or better than direct inversion (DI) for predicting the known stiffness of the data. Summary NNI results were also shown to be significantly correlated with DI results in the liver (R 2  = 0.974) and in the brain (R 2  = 0.915), and also correlated with established biological effects including fibrosis stage in the liver and age in the brain. Finally, repeatability error was lower in the brain using NNI compared to DI, and voxel-wise modeling using NNI stiffness maps detected larger effects than using DI maps with similar levels of smoothing. Artificial neural networks represent a new approach to inversion of MRE data. Summary results from NNI and DI are highly correlated and both are capable of detecting biologically relevant signals. Preliminary evidence suggests that NNI stiffness estimates may be more resistant to noise than an algebraic DI approach. Taken together, these results merit future investigation into NNIs to improve the estimation of stiffness in small regions. Magn Reson Med, 2017. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

  8. Prognostic Value of Controlled Attenuation Parameter by Transient Elastography.

    Science.gov (United States)

    Liu, Ken; Wong, Vincent Wai-Sun; Lau, Keith; Liu, Sienna Du; Tse, Yee-Kit; Yip, Terry Cheuk-Fung; Kwok, Raymond; Chan, Alex Yiu-Wa; Chan, Henry Lik-Yuen; Wong, Grace Lai-Hung

    2017-10-31

    Liver stiffness measurement (LSM) by transient elastography (TE) has been shown to predict outcomes in patients with liver disease. While controlled attenuation parameter (CAP) measurement can accurately quantify hepatic steatosis, its prognostic value is unknown. We aim to determine if CAP is predictive for liver-related events (LRE), non-hepatocellular carcinoma (HCC) cancers, and cardiovascular events (CVE). Consecutive patients with both a reliable LSM and ≥10 successful CAP measurements by TE from August 2012 to March 2016 were included in the analysis. LRE were defined as HCC or hepatic decompensation. CVE were defined as acute coronary syndrome (ACS), cerebrovascular accident (CVA), or coronary intervention (stenting or bypass). Of the 5,848 patients that were examined, 4,282 (56.7% male, median age 57 years) had adequate follow-up, reliable LSM (median 6.1 kPa), and ≥10 CAP measurements (median 250 dB/m). Indications for TE were: suspected non-alcoholic fatty liver disease (NAFLD) (40.7%), hepatitis B (HBV) (37.0%), hepatitis C (2.9%), and others (19.4%). During 8,540 patient-years of follow-up, there were 45 patients with LRE (34 HCC, 33 decompensations), 73 with newly diagnosed non-HCC cancers, and 65 with CVE (27 ACS, 25 CVA, and 35 coronary interventions). CAP did not predict LRE, non-HCC cancer, or CVE on univariate analysis. On multivariate analysis, LSM, male sex, platelet count, serum albumin, and HBV etiology independently predicted LRE; age was the only independent predictor of non-HCC cancer; while age, fasting blood glucose, total cholesterol, and creatinine predicted for CVE. Subgroup analyses of viral hepatitis and NAFLD patients revealed similar results. Neither the presence nor the severity of hepatic steatosis as measured by CAP predict LRE, cancer, or CVE in the short term.Am J Gastroenterol advance online publication, 31 October 2017; doi:10.1038/ajg.2017.389.

  9. Detection of dermal systemic sclerosis using noncontact optical coherence elastography

    Science.gov (United States)

    Liu, Chih-Hao; Du, Yong; Singh, Manmohan; Li, Jiasong; Wu, Chen; Han, Zhaolong; Raghunathan, Raksha; Hsu, Thomas; Noorani, Shezaan; Hicks, M. John; Mohan, Chandra; Larin, Kirill V.

    2016-03-01

    Systemic sclerosis (SSc) is a connective tissue disease that results in excessive accumulation of collagen in the skin and internal organs. Overall, SSc is a rare disorder, but has a high mortality, particularly in last decade of life. To improve the survival rate, an accurate and early diagnosis is crucial. Currently, the modified Rodnan skin score (mRSS) is the gold standard for evaluating SSc progression based on clinical palpation at 17 sites on the body. However, this procedure can be time consuming, and the assessed score may be biased by the experience of the clinician, causing inter- and intraobserver variabilities. Moreover, the instrinsic elasticity of skin may further bias the mRSS assessment in the early stages of SSc, such as oedematous. To overcome these limitations, there is a need for a rapid, accurate, and objective assessment technique. Optical coherence elastography (OCE) is a novel, rapidly emerging technique, which can assess mechanical contrast in tissues with micrometer spatial resolution. In this work, we demonstrate the first use of OCE to assess the mechanical properties of control and SSc-like diseased skin non-invasively. A focused air-pulse induced an elastic wave in the skin, which was detected by a home-built OCE system. The elastic wave propagated significantly faster in SSc skin compared to healthy skin. The Young's modulus of the SSc skin was significantly higher than that of normal skin (P<0.05). Thus, OCE was able to objectively differentiate healthy and fibrotic skin completely noninvasively and is a promising and potentially useful new technology for quantifying skin involvement in SSc.

  10. Doppler Ultrasound and Transient Elastography in Liver Transplant Patients for Noninvasive Evaluation of Liver Fibrosis in Comparison with Histology: A Prospective Observational Study.

    Science.gov (United States)

    Lutz, H H; Schroeter, B; Kroy, D C; Neumann, U; Trautwein, C; Tischendorf, J J W

    2015-09-01

    Accurate quantification of progressive liver disease is essential for therapeutic decisions and follow-up for patients who underwent liver transplantation. To evaluate the quality of noninvasive assessment of liver fibrosis in these patients, we compared Doppler ultrasound of the hepatic blood vessels as well as transient elastography (TE, FibroScan(®)) with liver biopsy following transplantation. We performed Doppler ultrasound of the hepatic veins, hepatic artery, and portal vein as well as a TE in 48 patients who underwent liver transplantation 12 months ago. Hepatic venous flow was evaluated by determination of the resistance index (HVRI) of the right hepatic vein. Doppler and TE results were compared with histopathologic workup of a 12-month protocol liver biopsy after transplantation. HVRI showed a high reliability in predicting liver fibrosis stage FII or higher (AUROC of 0.99 ± 0.001 for FII or higher, the HVRI hepatic artery did not show significant changes in blood flow in our study population. Hepatic vein flow resistance index is a valuable tool in noninvasive evaluation of liver fibrosis in liver transplantation follow-up predicting FII or higher and might help reducing the number of protocol biopsies needed.

  11. Reproducibility of shear wave elastography (SWE) in patients with chronic liver disease.

    Science.gov (United States)

    Mancini, Marcello; Salomone Megna, Angelo; Ragucci, Monica; De Luca, Massimo; Marino Marsilia, Giuseppina; Nardone, Gerardo; Coccoli, Pietro; Prinster, Anna; Mannelli, Lorenzo; Vergara, Emilia; Monti, Serena; Liuzzi, Raffaele; Incoronato, Mariarosaria

    2017-01-01

    The presence of significant fibrosis is an indicator for liver disease staging and prognosis. The aim of the study was to determine reproducibility of real-time shear wave elastography using a hepatic biopsy as the reference standard to identify patients with chronic liver disease. Forty patients with chronic liver disease and 12 normal subjects received shear wave elastography performed by skilled operators. Interoperator reproducibility was studied in 29 patients. Fibrosis was evaluated using the Metavir score. The median and range shear wave elastography values in chronic liver disease subjects were 6.15 kPa and 3.14-16.7 kPa and were 4.49 kPa and 2.92-7.32 kPa in normal subjects, respectively. With respect to fibrosis detected by liver biopsy, shear wave elastography did not change significantly between F0 and F1 (p = 0.334), F1 and F2 (p = 0.611), or F3 and F4 (0.327); a significant difference was observed between the F0-F2 and F3-F4 groups (p = 0.002). SWE also correlated with inflammatory activity (Rs = 0.443, p = 0.0023) and ALT levels (Rs = 0.287, p = 0.0804). Age, sex and body mass index did not affect shear wave elastography measurements. Using receiver operator characteristic curves, two threshold values for shear wave elastography were identified: 5.62 kPa for patients with fibrosis (≥F2; sensitivity 80%, specificity 69.4%, and accuracy 77%) and 7.04 kPa for patients with severe fibrosis (≥F3; sensitivity 88.9%, specificity 81%, and accuracy 89%). Overall interobserver agreement was excellent and was analysed using an interclass correlation coefficient (0.94; CI 0.87-0.97).This study shows that shear wave elastography executed by skilled operators can be performed on almost all chronic liver disease patients with high reproducibility. It is not influenced by age, sex or body mass index, identifies severely fibrotic patients and is also related to inflammatory activity.

  12. Reproducibility of shear wave elastography (SWE) in patients with chronic liver disease

    Science.gov (United States)

    Salomone Megna, Angelo; Ragucci, Monica; De Luca, Massimo; Marino Marsilia, Giuseppina; Nardone, Gerardo; Coccoli, Pietro; Prinster, Anna; Mannelli, Lorenzo; Vergara, Emilia; Monti, Serena; Liuzzi, Raffaele; Incoronato, Mariarosaria

    2017-01-01

    The presence of significant fibrosis is an indicator for liver disease staging and prognosis. The aim of the study was to determine reproducibility of real-time shear wave elastography using a hepatic biopsy as the reference standard to identify patients with chronic liver disease. Forty patients with chronic liver disease and 12 normal subjects received shear wave elastography performed by skilled operators. Interoperator reproducibility was studied in 29 patients. Fibrosis was evaluated using the Metavir score. The median and range shear wave elastography values in chronic liver disease subjects were 6.15 kPa and 3.14–16.7 kPa and were 4.49 kPa and 2.92–7.32 kPa in normal subjects, respectively. With respect to fibrosis detected by liver biopsy, shear wave elastography did not change significantly between F0 and F1 (p = 0.334), F1 and F2 (p = 0.611), or F3 and F4 (0.327); a significant difference was observed between the F0-F2 and F3-F4 groups (p = 0.002). SWE also correlated with inflammatory activity (Rs = 0.443, p = 0.0023) and ALT levels (Rs = 0.287, p = 0.0804). Age, sex and body mass index did not affect shear wave elastography measurements. Using receiver operator characteristic curves, two threshold values for shear wave elastography were identified: 5.62 kPa for patients with fibrosis (≥F2; sensitivity 80%, specificity 69.4%, and accuracy 77%) and 7.04 kPa for patients with severe fibrosis (≥F3; sensitivity 88.9%, specificity 81%, and accuracy 89%). Overall interobserver agreement was excellent and was analysed using an interclass correlation coefficient (0.94; CI 0.87–0.97).This study shows that shear wave elastography executed by skilled operators can be performed on almost all chronic liver disease patients with high reproducibility. It is not influenced by age, sex or body mass index, identifies severely fibrotic patients and is also related to inflammatory activity. PMID:29023554

  13. [Surgical treatment of chronic venous insufficiency].

    Science.gov (United States)

    Rosales, Antonio; Slagsvold, Carl-Erik; Jørgensen, Jørgen J; Sandbaek, Gunnar

    2009-11-19

    Patients with chronic venous insufficiency (CVI) may develop serious symptoms such as pain, oedema, venous claudication and leg ulcers. Conventional therapy includes compression therapy, elevation of the extremities, and in some cases surgical elimination of superficial varicose veins. This article presents and discusses surgical treatment (reconstructive deep venous surgery and transplantation) and endovascular therapy (percutaneous recanalization of post-thrombotic deep venous occlusions). The article is based on literature identified through non-systematic searches in the PubMed and Cochrane databases. After reconstructive deep venous surgery, ulcer healing is reported in 60-78 % of cases and clinical improvement in 90 %. After such surgery, the median ulcer-free period seems to be longer in primary (congenital, familial), 54 months, than in secondary (after deep vein thrombosis) chronic venous insufficiency (18 months). Recanalization of deep venous occlusions is successful in 90 % of patients who have undergone endovascular treatment of venous claudication and leg ulcer. Reconstructive deep venous surgery constitutes a real treatment choice for patients with chronic venous insufficiency for whom conventional measures have failed. The benefits are ulcer-free periods, clinical improvement, return to work and improved quality of life.

  14. Hyperhomocysteinemia and venous thromboembolic disease.

    Science.gov (United States)

    D'Angelo, A; Mazzola, G; Crippa, L; Fermo, I; Viganò D'Angelo, S

    1997-01-01

    In spite of the large number of reports showing that hyperhomocysteinemia (HHcy) is an independent risk factor for atherosclerosis and arterial occlusive disease, this metabolite of the methionine pathway is measured in relatively few laboratories and its importance is not fully appreciated. Recent data strongly suggest that mild HHcy is also involved in the pathogenesis of venous thromboembolic disease. The aim of this paper is to analyze the most recent advances in this field. The material examined in the present review includes articles and abstracts published in journals covered by the Science Citation Index and Medline. In addition the authors of the present article have been working in the field of mild HHcy as cause of venous thromboembolic disease. The studies examined provide very strong evidence supporting the role of moderate HHcy in the development of premature and/or recurrent venous thromboembolic disease. High plasma homocysteine levels are also a risk factor for deep vein thrombosis in the general population. Folic acid fortification of food has been proposed as a major tool for reducing coronary artery disease mortality in the United States. Vitamin supplementation may also reduce recurrence of venous thromboembolic disease in patients with HHcy. At the present time, however, the clinical efficacy of this approach has not been tested. In addition, the bulk of evidence indicates that fasting total homocysteine determinations can identify up to 50% of the total population of hyperhomocysteinemic subjects. Patients with isolated methionine intolerance may benefit from vitamin B6 supplementation. Homocysteine-lowering vascular disease prevention trials are urgently needed. Such controlled studies, however, should not focus exclusively on fasting homocysteine determinations and folic acid monotherapy.

  15. Efficacy of thyroid ultrasound elastography in differential diagnosis of small thyroid nodules

    Energy Technology Data Exchange (ETDEWEB)

    Dighe, Manjiri, E-mail: dighe@u.washington.edu [Department of Radiology, Box 357115, 1959 NE Pacific Street, University of Washington, Seattle, WA 98195 (United States); Luo, Si [Department of Bioengineering, University of Washington, William H. Foege Building, N510B, 3720 15th Ave NE, Seattle, WA 98195-5061 (United States); Cuevas, Carlos, E-mail: cuevas@u.washington.edu [Department of Radiology, Box 357115, 1959 NE Pacific Street, University of Washington, Seattle, WA 98195 (United States); Kim, Yongmin, E-mail: ykim@u.washington.edu [Department of Bioengineering, University of Washington, Box 355061, Seattle, WA 98195-5061 (United States)

    2013-06-15

    Objective: To explore the efficacy of thyroid ultrasound (US) elastography in differential diagnosis of small thyroid nodules. Methods: This HIPAA-compliant study was approved by the Institutional Review Board and all patients provided written informed consent. Thirty-five patients with 38 small thyroid nodules as seen on transverse ultrasound image formed our study population. An US examination and a separate thyroid elastography examination with pulsation from the carotid artery used as the compression source were performed before fine-needle aspiration. Baseband US data were acquired for off-line elastography processing, where a semi-quantitative index for each nodule was calculated. The Kruskal–Wallis nonparametric rank sum test was used to assess equality of population means among the different types of thyroid nodules. Maximum likelihood estimation of the curve parameters for a binomial receiver operating characteristic (ROC) curve was performed. Results: Elasticity contrast index calculated with elastography was effective in distinguishing between small papillary thyroid carcinomas (PTMC, n = 8) and other lesions (n = 30) in small thyroid nodules (p = 0.0036). The area under the ROC curve for diagnosing PTMCs was 0.812 with a 95% confidence interval of 0.653–0.920. The cut-off value of ECI of 3.6 led to a sensitivity of 100% and a specificity of 60% for detecting PTMCs. Conclusion: Noninvasive evaluation of small thyroid nodules is possible using thyroid US elastography with in vivo compression to pick out the most suspicious thyroid nodules for fine-needle aspiration (FNA) and avoid FNA in benign nodules.

  16. An elastography method based on the scanning contact resonance of a piezoelectric cantilever.

    Science.gov (United States)

    Fu, Ji; Li, Faxin

    2013-12-01

    Most tissues may become significantly stiffer than their normal states when there are lesions inside. The tissue's modulus can then act as an identification parameter for clinic diagnosis of tumors or fibrosis, which leads to elastography. This study introduces a novel elastography method that can be used for modulus imaging of superficial organs. This method is based on the scanning contact-resonance of a unimorph piezoelectric cantilever. The cantilever vibrates in its bending mode with the tip pressed tightly on the sample. The contact resonance frequency of the cantilever-sample system is tracked at each scanning point, from which the sample's modulus can be derived based on a beam dynamic model and a contact mechanics model. Scanning is performed by a three-dimensional motorized stage and the whole system is controlled by a homemade software program based on LabVIEW. Testing on in vitro beef tissues indicates that the fat and the muscle can be easily distinguished using this system, and the accuracy of the modulus measurement can be comparable with that of nanoindentation. Imaging on homemade gelatin phantoms shows that the depth information of the abnormalities can be qualitatively obtained by varying the pressing force. The detection limit of this elastography method is specially examined both experimentally and numerically. Results show that it can detect the typical lesions in superficial organs with the depth of several centimeters. The lateral resolution of this elastography method∕system is better than 0.5 mm, and could be further enhanced by using more scanning points. The proposed elastography system can be regarded as a sensitive palpation robot, which may be very promising in early diagnosis of tumors in superficial organs such as breast and thyroid.

  17. An elastography method based on the scanning contact resonance of a piezoelectric cantilever

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Ji; Li, Faxin, E-mail: lifaxin@pku.edu.cn [State Key Lab for Turbulence and Complex Systems, College of Engineering, Peking University, Beijing 100871, China and HEDPS, Center for Applied Physics and Technologies, Peking University, Beijing 100871 (China)

    2013-12-15

    Purpose: Most tissues may become significantly stiffer than their normal states when there are lesions inside. The tissue's modulus can then act as an identification parameter for clinic diagnosis of tumors or fibrosis, which leads to elastography. This study introduces a novel elastography method that can be used for modulus imaging of superficial organs. Methods: This method is based on the scanning contact-resonance of a unimorph piezoelectric cantilever. The cantilever vibrates in its bending mode with the tip pressed tightly on the sample. The contact resonance frequency of the cantilever-sample system is tracked at each scanning point, from which the sample's modulus can be derived based on a beam dynamic model and a contact mechanics model. Scanning is performed by a three-dimensional motorized stage and the whole system is controlled by a homemade software program based on LabVIEW. Results: Testing onin vitro beef tissues indicates that the fat and the muscle can be easily distinguished using this system, and the accuracy of the modulus measurement can be comparable with that of nanoindentation. Imaging on homemade gelatin phantoms shows that the depth information of the abnormalities can be qualitatively obtained by varying the pressing force. The detection limit of this elastography method is specially examined both experimentally and numerically. Results show that it can detect the typical lesions in superficial organs with the depth of several centimeters. The lateral resolution of this elastography method/system is better than 0.5 mm, and could be further enhanced by using more scanning points. Conclusions: The proposed elastography system can be regarded as a sensitive palpation robot, which may be very promising in early diagnosis of tumors in superficial organs such as breast and thyroid.

  18. A threshold value in Shear Wave elastography to rule out malignant thyroid nodules: A reality?

    Energy Technology Data Exchange (ETDEWEB)

    Veyrieres, J.-B., E-mail: jbveyrieres@hotmail.fr [Département d’imagerie médicale, Hôpital d’Instruction des Armées St Anne, Bd Saint Anne, BP 20545 Toulon cedex (France); Albarel, F., E-mail: frederique.albarel@ap-hm.fr [Département médical d’endocrinologie et des pathologies métaboliques, Hôpital Universitaire la Timone, Assistance publique des Hôpitaux de Marseille, 264 rue Saint Pierre, 13385 Marseille cedex 5 (France); Lombard, J. Vaillant, E-mail: Josiane.vaillant@ap-hm.fr [Département d’imagerie médicale, Hôpital Universitaire la Timone, Assistance publique des Hôpitaux de Marseille, 264 rue Saint Pierre, 13385 Marseille cedex 5 (France); Berbis, J., E-mail: Julie.berbis@ap-hm.fr [Département de santé publique, Université de Médecine, 27, Bd Jean Moulin, 13385 Marseille cedex 5 (France); Sebag, F., E-mail: frederic.sebag@ap-hm.fr [Département de chirurgie des pathologies endocriniennes et métaboliques, Hôpital Universitaire la Timone, Assistance publique des Hôpitaux de Marseille, 264 rue Saint Pierre, 13385 Marseille cedex 5 (France); and others

    2012-12-15

    Objectives: To evaluate hability of a threshold value in ShearWave™ elastography to rule out malignant thyroid nodules while studying its pertinence in association with morphological signs. Equipment and methods: 148 patients (110 women and 38 men; 52.5 y.o. 15.8) referred for surgery of thyroid nodules underwent standard ultrasound as well as elastography. Characteristics of the morphological signs and maximum elastographic index were calculated in relation to histology. Association of morphological signs alone and then of elastography was also evaluated. One hundred and fifty one nodules were studied on a double-blind basis. Results: 297 nodules were studied. Thirty-five cancers were detected (11.6%). Elastographic index was higher in malignant nodules (115 kPa 60.4) than in benign nodules (41 kPa 25.8) (p < 0.001, Student's t-test). Cut off value of 66 kPa was the best to discriminate malignant nodules with a sensitivity of 80% (CI 95%, 62.5; 90.9) and a specificity of 90.5% (CI 95%, 86.1; 93.6) (p = 0.0001). Association of elastography and morphological ultrasound signs presented a sensitivity of 97% (CI 95%, 83.3; 99.8) and a negative predictive value of 99.5% (CI 95%, 95.6; 99.9). Interobserver reproducibility proved to be excellent with an interclass correlation of 0.97 (CI 95%, 0.96; 0.98) (p < 0.001). Conclusion: The 66 kPa threshold in Shear Wave elastography is the best ultrasound sign to rule out malignant thyroid nodules. The method is simple, quantitative, reproducible and usable in the study of nodules larger than 3 cm. Progress must still be made in the study of calcified nodules and follicular tumors.

  19. Compression Real-time Elastography for Evaluation of Salivary Gland Lesions: A Meta-analysis.

    Science.gov (United States)

    Li, Changtian; Zhang, Changsheng; Li, Nan; Li, Junlai

    2016-05-01

    To evaluate the performance of compression real-time elastography for differentiation between benign and malignant salivary gland lesions. A systematic literature database search was conducted. Pooled sensitivity, specificity, positive likelihood ratio (LR+), and negative likelihood ratio (LR-) values for real-time elastography were analyzed. Summary receiver operating characteristic (ROC) curves were also constructed. Heterogeneity was evaluated by χ(2) and I(2) tests. I(2) > 50% or P analysis was performed to evaluate the clinical utility of real-time elastography. When heterogeneity was found, subgroup analyses were used to explore the sources of heterogeneity. A sensitivity analysis was conducted by omitting 1 study at a time and examining the influence of each individual study on the overall results. Nine articles with 581 lesions were included. The pooled sensitivity and specificity of real-time elastography for differentiation between benign and malignant lesions were 76% (95% confidence interval [CI], 65%-85%; 95% prediction interval [PI], 29%-95%) and 73% (95% CI, 62%-81%; 95% PI, 24%-96%), respectively. The LR+ and LR- were 2.81 (95% CI, 1.79-4.39; 95% PI, 0.65-12.16) and 0.33 (95% CI, 0.20-0.55; 95% PI, 0.07-1.69). The area under the ROC curve was 0.81 (95% CI, 0.77-0.84). No publication bias was detected, according to the Deek funnel plot (P = .51). The Fagan plot showed that when pretest probabilities were 25%, 50%, and 75%, positive posttest probabilities were 48%, 74%, and 89%, and negative probabilities were 10%, 25%, and 50%. Real-time elastography is a novel supplementary adjunct to conventional sonography for evaluation of salivary gland lesions. However, its overall accuracy is less promising, and biopsy may still be necessary in routine clinical practice. © 2016 by the American Institute of Ultrasound in Medicine.

  20. Venous drainage of the face.

    Science.gov (United States)

    Onishi, S; Imanishi, N; Yoshimura, Y; Inoue, Y; Sakamoto, Y; Chang, H; Okumoto, T

    2017-04-01

    The venous anatomy of the face was examined in 12 fresh cadavers. Venograms and arteriovenograms were obtained after the injection of contrast medium. In 8 of the 12 cadavers, a large loop was formed by the facial vein, the supratrochlear vein, and the superficial temporal vein, which became the main trunk vein of the face. In 4 of the 12 cadavers, the superior lateral limb of the loop vein was less well developed. The loop vein generally did not accompany the arteries of the face. Cutaneous branches of the loop vein formed a polygonal venous network in the skin, while communicating branches ran toward deep veins. These findings suggest that blood from the dermis of the face is collected by the polygonal venous network and enters the loop vein through the cutaneous branches, after which blood flows away from the face through the superficial temporal vein, the facial vein, and the communicating branches and enters the deep veins. Copyright © 2016 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  1. Therapeutic ultrasound to promote healing of lower extremity venous ulcers: CAT

    Directory of Open Access Journals (Sweden)

    Raúl Alberto Aguilera Eguía

    2013-10-01

    Full Text Available Purpose. The aim of this CAT (Critically Appraised Topic was to check the validity of the results and applicability regarding the effectiveness of therapeutic ultrasound in increasing healing of lower extremity ulcers and to answer the question: In subjects that have lower extremity venous ulcers, does high-frequency therapeutic ultrasound improve healing rate compared to placebo? Method. We conducted an analysis of the article "Therapeutic Ultrasound for lower extremity venous ulcers, Cochrane Systematic Review" of Cullum, et al (2010. Results. The application of high-frequency therapeutic ultrasound could increase healing in patients with lower extremity venous ulcers, RR = 1.40 (95% CI 1.00 to 1.96. Conclusion. The use of therapeutic ultrasound to promote healing in lower extremity venous ulcers is neither endorsed nor discouraged.

  2. Does standoff material affect acoustic radiation force impulse elastography? A preclinical study of a modified elastography phantom.

    Science.gov (United States)

    Hollerieth, Katharina; Gaßmann, Bernhard; Wagenpfeil, Stefan; Kemmner, Stephan; Heemann, Uwe; Stock, Konrad Friedrich

    2017-07-28

    This study was conducted to determine the influence of standoff material on acoustic radiation force impulse (ARFI) measurements in an elasticity phantom by using two different probes. Using ARFI elastography, 10 observers measured the shear wave velocity (SWV, m/sec) in different lesions of an elasticity phantom with a convex 4C1 probe and a linear 9L4 probe. The experimental setup was expanded by the use of an interposed piece of porcine muscle as standoff material. The probe pressure on the phantom was registered. Faulty ARFI measurements occurred more often when quantifying the hardest lesion (74.0 kPa 4.97 m/sec) by the 9L4 probe with the porcine muscle as a standoff material interposed between the probe and the phantom. The success rate for ARFI measurements in these series was 52.4%, compared with 99.5% in the other series. The SWV values measured with the 9L4 probe were significantly higher (3.33±1.39 m/sec vs. 2.60±0.74 m/sec, Pmaterial were lower than those without the muscle (significant for 9L4, P=0.040). The deviation from the reference value and the variance increased significantly with the 9L4 probe if the muscle was in situ (B=0.27, P=0.004 and B=0.32, Pstudy, the pressure exerted by the operator had no effect on the SWV values. The presence of porcine muscle acting as a standoff material influenced the occurrence of failed measurements as well as the variance and the accuracy of the measured values. The linear high-frequency probe was particularly affected.

  3. Shear Wave Elastography May Add a New Dimension to Ultrasound Evaluation of Thyroid Nodules: Case Series with Comparative Evaluation

    Directory of Open Access Journals (Sweden)

    Rafal Z. Slapa

    2012-01-01

    Full Text Available Although elastography can enhance the differential diagnosis of thyroid nodules, its diagnostic performance is not ideal at present. Further improvements in the technique and creation of robust diagnostic criteria are necessary. The purpose of this study was to compare the usefulness of strain elastography and a new generation of elasticity imaging called supersonic shear wave elastography (SSWE in differential evaluation of thyroid nodules. Six thyroid nodules in 4 patients were studied. SSWE yielded 1 true-positive and 5 true-negative results. Strain elastography yielded 5 false-positive results and 1 false-negative result. A novel finding appreciated with SSWE, were punctate foci of increased stiffness corresponding to microcalcifications in 4 nodules, some not visible on B-mode ultrasound, as opposed to soft, colloid-inspissated areas visible on B-mode ultrasound in 2 nodules. This preliminary paper indicates that SSWE may outperform strain elastography in differentiation of thyroid nodules with regard to their stiffness. SSWE showed the possibility of differentiation of high echogenic foci into microcalcifications and inspissated colloid, adding a new dimension to thyroid elastography. Further multicenter large-scale studies of thyroid nodules evaluating different elastographic methods are warranted.

  4. Starling curves and central venous pressure

    OpenAIRE

    Berlin, Cheryl; Bakker, Jan

    2014-01-01

    textabstractRecent studies challenge the utility of central venous pressure monitoring as a surrogate for cardiac preload. Starting with Starling’s original studies on the regulation of cardiac output, this review traces the history of the experiments that elucidated the role of central venous pressure in circulatory physiology. Central venous pressure is an important physiologic parameter, but it is not an independent variable that determines cardiac output.

  5. Shear wave elastography in medullary thyroid carcinoma diagnostics

    Directory of Open Access Journals (Sweden)

    Katarzyna Dobruch-Sobczak

    2015-12-01

    Full Text Available Shear wave elastography (SWE is a modern method for the assessment of tissue stiffness. There has been a growing interest in the use of this technique for characterizing thyroid focal lesions, including preoperative diagnostics. Aim: The aim of the study was to assess the clinical usefulness of SWE in medullary thyroid carcinoma (MTC diagnostics. Materials and methods: A total of 169 focal lesions were identifi ed in the study group (139 patients, including 6 MTCs in 4 patients (mean age: 45 years. B-mode ultrasound and SWE were performed using Aixplorer (SuperSonic, Aix-en-Provence, with a 4–15 MHz linear probe. The ultrasound was performed to assess the echogenicity and echostructure of the lesions, their margin, the halo sign, the height/width ratio (H/W ratio, the presence of calcifi cations and the vascularization pattern. This was followed by an analysis of maximum and mean Young’s (E modulus values for MTC (EmaxLR, EmeanLR and the surrounding thyroid tissues (EmaxSR, EmeanSR, as well as mean E-values (EmeanLRz for 2 mm region of interest in the stiffest zone of the lesion. The lesions were subject to pathological and/or cytological evaluation. Results: The B-mode assessment showed that all MTCs were hypoechogenic, with no halo sign, and they contained micro- and/ or macrocalcifi cations. Ill-defi ned lesion margin were found in 4 out of 6 cancers; 4 out of 6 cancers had a H/W ratio > 1. Heterogeneous echostructure and type III vascularity were found in 5 out of 6 lesions. In the SWE, the mean value of EmaxLR for all of the MTCs was 89.5 kPa and (the mean value of EmaxSR for all surrounding tissues was 39.7 kPa Mean values of EmeanLR and EmeanSR were 34.7 kPa and 24.4 kPa, respectively. The mean value of EmeanLRz was 49.2 kPa. Conclusions: SWE showed MTCs as stiffer lesions compared to the surrounding tissues. The lesions were qualifi ed for fi ne needle aspiration biopsy based on B-mode assessment. However, the diagnostic algorithm

  6. Central venous line complications and tip detection

    Directory of Open Access Journals (Sweden)

    Ameneh Rezaee Gheshlaghi

    2015-06-01

    Full Text Available Central venous line is one of a creative instrument that saves human’s life in critical medical situation. Central venous line access is frequently involved in the disease management. It is used for rapid fluid therapy, transvenous pacemakers, infusion of some medications, hemodialysis or plasmapheresis and etc. Most of the emergency departments have some staffs that are trained for central venous line insertion but related complications occur during central venous line placement.Central venous line might have some complications and complication follow-up should be considered. Thromboembolism and infection are two important medical complications. Arterial puncture, hematoma, pneumothorax and hemothorax are mechanical Central venous line complications. Chest X-ray and some other techniques should be used for detecting these complications.Central venous line tip misplace is a considerable problem for emergency department staffs, previously chest X-ray has been used for central venous line misplace detection. In some recent studies, contrast-enhanced ultrasonography and intravascular electrocardiography have been used for central venous line misplace.

  7. Quantitative assessment of corneal biomechanical properties using optical coherence elastography and a modified Rayleigh Lamb-frequency model

    Science.gov (United States)

    Han, Zhaolong; Aglyamov, Salavat R.; Li, Jiasong; Singh, Manmohan; Wang, Shang; Vantipalli, Srilatha; Wu, Chen; Liu, Chih-hao; Twa, Michael D.; Larin, Kirill V.

    2015-03-01

    This study reports the application of a modified Rayleigh-Lamb frequency equation (RLFE) to a noncontact optical coherence elastography (OCE) method for quantitative assessment of the biomechanical properties of a porcine cornea. A focused air-pulse induced an elastic wave in the cornea, which was imaged by a phasestabilized optical coherence tomography (OCT) system. From the displacement data acquired by the OCT system, phase velocities of the mechanical wave were extracted by spectral analysis using a fast Fourier transform. Experiments were conducted on 2% agar phantom samples, and the Young's moduli were assessed by the Rayleigh-Lamb frequency equation, which was validated using uniaxial mechanical compression testing. The Rayleigh-Lamb frequency equation was then applied to OCE data from a normal porcine cornea, in which the fluid-solid effect was considered. The Young's modulus of the porcine cornea was measured to be ~60 kPa and the shear viscosity was ~0.33 Pa·s. The combination of OCE and RLFE is a promising noninvasive method for the estimation of the biomechanical properties of the cornea in vivo.

  8. Development of oil-in-gelatin phantoms for viscoelasticity measurement in ultrasound shear wave elastography.

    Science.gov (United States)

    Nguyen, Man M; Zhou, Shiwei; Robert, Jean-Luc; Shamdasani, Vijay; Xie, Hua

    2014-01-01

    Because tissues consist of solid and fluid materials, their mechanical properties should be characterized in terms of both elasticity and viscosity. Although the elastic properties of tissue-mimicking phantoms have been extensively studied and well characterized in commercially available phantoms, their viscous properties have not been fully investigated. In this article, a set of 14 tissue-mimicking phantoms with different concentrations of gelatin and castor oil were fabricated and characterized in terms of acoustic and viscoelastic properties. The results indicate that adding castor oil to gelatin phantoms decreases shear modulus, but increases shear wave dispersion. For 3% gelatin phantoms containing 0%, 10%, 20% and 40% oil, the measured shear moduli are 2.01 ± 0.26, 1.68 ± 0.25, 1.10 ± 0.22 and 0.88 ± 0.17 kPa, and the Voigt-model coupled shear viscosities are 0.60 ± 0.11, 0.89 ± 0.07, 1.05 ± 0.11 and 1.06 ± 0.13 Pa·s, respectively. The results also confirm that increasing the gelatin concentration increases shear modulus. For phantoms containing 3%, 4%, 5%, 6% and 7% gelatin, the measured shear moduli are 2.01 ± 0.26, 3.10 ± 0.34, 4.18 ± 0.84, 8.05 ± 1.00 and 10.24 ± 1.80 kPa at 0% oil and 1.10 ± 0.22, 1.97 ± 0.20, 3.13 ± 0.63, 4.60 ± 0.60 and 8.43 ± 1.39 kPa at 20% oil, respectively. The phantom recipe developed in this study can be used in validating ultrasound shear wave elastography techniques for soft tissues. Copyright © 2014 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  9. Ultrasound-Based Shear Wave Elastography in the Assessment of Patients with Diabetic Kidney Disease.

    Science.gov (United States)

    Bob, Flaviu; Grosu, Iulia; Sporea, Ioan; Bota, Simona; Popescu, Alina; Sima, Alexandra; Şirli, Roxana; Petrica, Ligia; Timar, Romulus; Schiller, Adalbert

    2017-10-01

    In previous studies of acoustic radiation force impulse (ARFI) elastography, using Virtual Touch tissue quantification (VTQ) (Siemens Acuson S2000), it was reported that the measurement of renal shear wave speed in patients with chronic kidney disease (CKD) is not influenced exclusively by renal fibrosis. The purpose of the present study was to analyze the role of VTQ in patients with diabetic kidney disease, considered the main cause of CKD. The study group included 164 patients: 80 patients with diabetic kidney disease (DKD) and 84 without renal disease or diabetes mellitus. In each subject in lateral decubitus, five valid VTQ measurements were performed in each kidney and a median value was calculated, the result being expressed in meters/second. The following means of the median values were obtained In DKD patients, the means of the median values were for VTQ right kidney, 2.21 ± 0.71 m/s, and for VTQ left kidney, 2.13 ± 0.72 m/s, whereas in the normal controls statistically significant higher values were obtained: 2.58 ± 0.78 m/s for VTQ right kidney (p = 0.0017) and 2.46 ± 0.81 m/s for VTQ left kidney (p = 0.006). Patients with an estimated glomerular filtration rate (eGFR) >60 mL/min (DKD stages 1 and 2 together with normal controls) had a significantly higher kidney shear wave speed compared with patients with an eGFR 60 mL/min (either normal controls or diabetic patients with DKD stages 1 and 2), and values decrease with the decrease in eGFR. However, proteinuria, diabetic retinopathy and glycated hemoglobin have no influence on VTQ. Copyright © 2017 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  10. Venous Thromboembolism in Patients With Thrombocytopenia

    DEFF Research Database (Denmark)

    Bælum, Jens Kristian; Ellingsen Moe, Espen; Nybo, Mads

    2017-01-01

    BACKGROUND: Venous thromboembolism (VTE) is a frequent and potentially lethal condition. Venous thrombi are mainly constituted of fibrin and red blood cells, but platelets also play an important role in VTE formation. Information about VTE in patients with thrombocytopenia is, however, missing. O...

  11. Venous and arterial thrombosis in dialysis patients

    NARCIS (Netherlands)

    Ocak, Gurbey; Vossen, Carla Y.; Rotmans, Joris I.; Lijfering, Willem M.; Rosendaal, Frits R.; Parlevliet, Karien J.; Krediet, Ray T.; Boeschoten, Els W.; Dekker, Friedo W.; Verduijn, Marion

    2011-01-01

    Whether the risk of both venous and arterial thrombosis is increased in dialysis patients as compared to the general population is unknown. In addition, it is unknown which subgroups are at highest risk. Furthermore, it is unknown whether having a history of venous thrombosis or arterial thrombosis

  12. An unusual Complication of Central Venous Cannulation

    Directory of Open Access Journals (Sweden)

    Ashvini Kumar

    2013-04-01

    Full Text Available Central venous catheter (CVC hub fracture is a rare complication of central venous cannulation. We report a case where catheter hub fracture was detected immediately after CVC insertion. Causes of catheter hub fracture and its complications are discussed.

  13. Pulmonary venous abnormalities encountered on pre ...

    African Journals Online (AJOL)

    Multidetector computed tomography (MDCT) elegantly renders pulmonary venous anatomy. With increasing numbers of radiofrequency ablation procedures being performed, there is now a greater emphasis on pre-procedure imaging to delineate this anatomy. Pulmonary venous mapping studies can be performed with or ...

  14. VENOUS THROMBOEMBOLISM PROPHYLAXIS – THE OTHER ...

    African Journals Online (AJOL)

    VENOUS THROMBOEMBOLISM PROPHYLAXIS – THE OTHER SIDE OF THE COIN: A REVIEW OF LITERATURE ... Background: There are no local guidelines for prophylaxis against Venous Thrombo-Embolism (VTE). In the absence of any .... of leg ulceration in the age matched general population. (9.6% to 12.6%).

  15. Sex-specific aspects of venous thrombosis

    NARCIS (Netherlands)

    Roach, Rachel Elizabeth Jo

    2014-01-01

    Venous thrombosis is a disease that occurs in 1-2 per 1000 people per year. At the time of their first venous thrombosis, approximately 50% of women are exposed to reproductive risk factors (oral contraception, postmenopausal hormone therapy, pregnancy and the puerperium). In this thesis, we showed

  16. Thromboelastography in patients with cerebral venous thrombosis

    NARCIS (Netherlands)

    Koopman, Karen; Uyttenboogaart, Maarten; Hendriks, Herman G. D.; Luijckx, Gert-Jan; Cramwinckel, Ivo R.; Vroomen, Patrick C.; De Keyser, Jacques; van der Meer, Jan

    Introduction: Cerebral venous thrombosis (CVT) is a rare presentation of venous thrombosis and has been associated with many conditions. In about 20% no risk factor is identified. The aim of this study was to assess the clot formation by thromboelastography (TEG) in patients with a history of CVT

  17. Starling curves and central venous pressure

    NARCIS (Netherlands)

    C. Berlin (Cheryl); J. Bakker (Jan)

    2014-01-01

    textabstractRecent studies challenge the utility of central venous pressure monitoring as a surrogate for cardiac preload. Starting with Starling’s original studies on the regulation of cardiac output, this review traces the history of the experiments that elucidated the role of central venous

  18. Heritability of chronic venous disease

    Science.gov (United States)

    Krusche, Petra; Wolf, Andreas; Krawczak, Michael; Timm, Birgitt; Nikolaus, Susanna; Frings, Norbert; Schreiber, Stefan

    2010-01-01

    Varicose veins without skin changes have a prevalence of approximately 20% in Northern and Western Europe whereas advanced chronic venous insufficiency affects about 3% of the population. Genetic risk factors are thought to play an important role in the aetiology of both these chronic venous diseases (CVD). We evaluated the relative genetic and environmental impact upon CVD risk by estimating the heritability of the disease in 4,033 nuclear families, comprising 16,434 individuals from all over Germany. Upon clinical examination, patients were classified according to the CEAP guidelines as either C2 (simple varicose veins), C3 (oedema), C4 (skin changes without ulceration), C5 (healed ulceration), or C6 (active ulcers). The narrow-sense heritability (h2) of CVD equals 17.3% (standard error 2.5%, likelihood ratio test P = 1.4 × 10−13). The proportion of disease risk attributable to age (at ascertainment) and sex, the two main risk factors for CVD, was estimated as 10.7% (Kullback–Leibler deviance R2). The heritability of CVD is high, thereby suggesting a notable genetic component in the aetiology of the disease. Systematic population-based searches for CVD susceptibility genes are therefore warranted. PMID:20354728

  19. Compression for venous leg ulcers.

    Science.gov (United States)

    O'Meara, Susan; Cullum, Nicky A; Nelson, E Andrea

    2009-01-21

    Around one percent of people in industrialised countries will suffer from a leg ulcer at some time. The majority of these leg ulcers are due to problems in the veins, resulting in an accumulation of blood in the legs. Leg ulcers arising from venous problems are called venous (varicose or stasis) ulcers. The main treatment has been a firm compression garment (bandage or stocking) in order to aid venous return. There is a large number of compression garments available and it is unclear whether they are effective in treating venous ulcers and which compression garment is the most effective. To undertake a systematic review of all randomised controlled trials of the clinical effectiveness of compression bandage or stocking systems in the treatment of venous leg ulceration.Specific questions addressed by the review are:1. Does the application of compression bandages or stockings aid venous ulcer healing? 2. Which compression bandage or stocking system is the most effective? For this update we searched the Cochrane Wounds Group Specialised Register (14/10/08); The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 4 2008); Ovid MEDLINE (1950 to October Week 1 2008); Ovid EMBASE (1980 to 2008 Week 41) and Ovid CINAHL (1982 to October Week 1 2008). No date or language restrictions were applied. Randomised controlled trials recruiting people with venous leg ulceration that evaluated any type of compression bandage system or compression hosiery were eligible for inclusion. Comparators included no compression (e.g. primary dressing alone, non-compressive bandage) or an alternative type of compression. Trials had to report an objective measure of ulcer healing in order to be included (primary outcome for the review). Secondary outcomes of the review included ulcer recurrence, costs, quality of life, pain, adverse events and withdrawals. There was no restriction on date, language or publication status of trials. Details of eligible studies were

  20. [Central venous blood gas analysis].

    Science.gov (United States)

    Marano, Marco; D'Amato, Anna; Guiotto, Giovanna; Schiraldi, Fernando

    2015-01-01

    The hemodialysis might interfere with patients hemodynamic, as the technique allows a sophisticated game with extra and intravascular fluids. As the cardiocirculatory response could sometimes be unpredictable, it is interesting to collect valuable information by reaching a deep understanding of the tissue metabolism which is mirrored by the blood gas analysis of variations in arterial and central venous blood samples. Particularly interesting are the time course variations of the central venous hemoglobin saturation (ScvO2), which are directly related to the patient with O2-demand as well as to the O2-Delivery (DO2). The ScvO2 is determined by four parameters (cardiac output, Hb concentration, arterial Hb saturation and O2 consumption): If the fluids subtraction during dialysis was about to determine an occult hypoperfusion, the ScvO2 reduction would be a timely warning sign to be considered. Moreover, while the normal veno-arterial PCO2 difference is 2-4 mmHg, whenever a mismatch between O2-demand and DO2arise, a larger v-aPCO2 difference should be observed.

  1. Volume tests for chronic venous insufficiency: an appraisal.

    Science.gov (United States)

    Peirce, E C; Chiang, K; Schanzer, H

    1991-05-01

    Chronic venous disease is increasingly treated surgically with a variety of experimental procedures. Noninvasive volume tests are commonly used before surgery to select patients and after surgery to assess results. Rapid volume changes are considered to indicate regurgitation. Rigorous statistical validation of tests and the confounding nature of unmeasured arterial inflow are seldom considered. Volume changes were measured in 29 control limbs and 35 limbs with venous disease, with mercury-in-silicone rubber strain gauges, for both exercise and elevation. Normalization for arterial flow permitted calculation of the regurgitation rate. Normal (95% confidence) limits for measured and calculated parameters were determined. Specificity was shown by the percent of normal parameter values for control limbs and sensitivity by the percent of abnormal values for extremities with venous disease. Arterial flow significantly altered volume curves. Normalization increased specificity and sensitivity significantly. Calf exercise tests, even normalized, were too insensitive to be reliable. Elevation tests were significantly more sensitive for determining regurgitation. However, exercise tests were useful and supplied important information about the calf muscle pump. We conclude that, as currently used, many limb volume test procedures are unsuitable but could be improved significantly by normalization to reduce the confounding effect of regional arterial flow and use of an elevation test to measure regurgitation.

  2. Endovenous thermal ablation for healing venous ulcers and preventing recurrence.

    Science.gov (United States)

    Samuel, Nehemiah; Carradice, Daniel; Wallace, Tom; Smith, George E; Chetter, Ian C

    2013-10-04

    venous leg ulcers were eligible for inclusion. Trials had to report on at least one objective measure of ulcer healing (primary outcome) such as proportion of ulcers healed at a given time point, time to complete healing, change in ulcer size, proportion of ulcers recurring over a given time period, or at a specific point, and ulcer-free days. Secondary outcomes sought included patient-reported quality of life, economic data and adverse events. Details of potentially eligible studies were extracted and summarised using a data extraction table. Data extraction and validity assessment were performed independently by two review authors, and any disagreements resolved by consensus or by arbitration of a third review author. No eligible randomised controlled trials were identified. There is an absence of evidence regarding the effects of superficial endovenous thermal ablation on ulcer healing, recurrence or quality of life of people with venous leg ulcer disease. The review identified no randomised controlled trials on the effects on ulcer healing, recurrence or quality of life, of superficial endovenous thermal ablation in people with active or healed venous leg ulcers. Adequately-powered, high quality randomised controlled trials comparing endovenous thermal ablative interventions with compression therapy are urgently required to explore this new treatment strategy. These should measure and report outcomes that include time to ulcer healing, ulcer recurrence, quality of life and cost-effectiveness.

  3. A comparative study of strain and shear-wave elastography in an elasticity phantom

    DEFF Research Database (Denmark)

    Carlsen, Jonathan F.; Pedersen, Malene R; Ewertsen, Caroline

    2015-01-01

    OBJECTIVE. The purpose of this study was to assess the diagnostic accuracy of strain and shear-wave elastography for determining targets of varying stiffness in a phantom. The effect of target diameter on elastographic assessments and the effect of depth on shear-wave velocity were also...... investigated. MATERIALS AND METHODS. We examined 20 targets of varying diameters (2.5-16.7 mm) and stiffnesses (8, 14, 45, and 80 kPa) with a 4-9-MHz linear-array transducer. Targets were evaluated 10 times with three different methods-shear-wave elastography, strain ratio, and strain histogram analysis....... RESULTS. Strain ratio and strain histogram AUCs were higher than the shear-wave velocity AUC (p Strain ratios were superior (p = 0...

  4. EFSUMB Guidelines and Recommendations on the Clinical Use of Liver Ultrasound Elastography, Update 2017 (Long Version)

    DEFF Research Database (Denmark)

    Dietrich, Christoph F; Bamber, Jeffrey; Berzigotti, Annalisa

    2017-01-01

    We present here the first update of the 2013 EFSUMB (European Federation of Societies for Ultrasound in Medicine and Biology) Guidelines and Recommendations on the clinical use of elastography, focused on the assessment of diffuse liver disease. The first part (long version) of these Guidelines...... and Recommendations deals with the basic principles of elastography and provides an update of how the technology has changed. The practical advantages and disadvantages associated with each of the techniques are described, and guidance is provided regarding optimization of scanning technique, image display, image...... Levels of Evidence. This updated document is intended to act as a reference and to provide a practical guide for both beginners and advanced clinical users....

  5. Assessment of biopsy-proven liver fibrosis by two-dimensional shear wave elastography

    DEFF Research Database (Denmark)

    Herrmann, Eva; de Lédinghen, Victor; Cassinotto, Christophe

    2018-01-01

    equipment were contacted to share their data. Retrospective statistical analysis used direct and paired receiver operating characteristic (ROC) and area under the ROC curve (AUROC) analysis accounting for random effects. RESULTS: Data on both 2D-SWE and liver biopsy was available in 1134 patients from 13......BACKGROUND AND AIMS: 2D shear wave elastography (2D-SWE) has proven to be efficient for the evaluation of liver fibrosis in small to moderate size clinical trials. We aimed at running a larger scale meta-analysis of individual data. METHODS: Centers which have worked with Aixplorer ultrasound...... sites, as well as on successful transient elastography (TE) in 665 patients. Most patients had chronic hepatitis C (HCV, n = 379), hepatitis B (HBV, n = 400) or non-alcoholic fatty liver disease (NAFLD, n = 156). AUROCs of 2D-SWE in patients with HCV, HBV and NAFLD were 86.3%, 90.6% and 85...

  6. Elastography and diffusion-weighted MRI in patients with rectal cancer

    DEFF Research Database (Denmark)

    Rafaelsen, Søren Rafael; Vagn-Hansen, Chris Aksel; Sørensen, Torben

    2015-01-01

    .86), slope = -1.949 (95% CI: -1.31 to -2.59), p MRI ADC measurements in rectal tumours. The relationship between ARFI and ADC measurement was linear in our study population. Advances in knowledge: This work describes......OBJECTIVE: The current literature has described the usefulness of elastography and diffusion-weighted MRI in patients with cancer, but to the best of our knowledge so far none of them has compared the two new methods. The tumour cell density is related to the MRI-measured apparent diffusion......-weighted coefficient (ADC). The purpose of the present study was to compare quantitative elastography based on ultrasound shear wave measurements with MRI ADC. METHODS: We prospectively examined 52 patients with histopathologically proven rectal cancer. The mean age was 67 years (range 42-90 years). Males: 39, females...

  7. A soft patellar tendon on ultrasound elastography is associated with pain and functional deficit in volleyball players.

    Science.gov (United States)

    Ooi, Chin Chin; Richards, Paula J; Maffulli, Nicola; Ede, David; Schneider, Michal E; Connell, David; Morrissey, Dylan; Malliaras, Peter

    2016-05-01

    To investigate the diagnostic performance of grey scale Ultrasound (US), power Doppler (PD) and US elastography for diagnosing painful patellar tendinopathy, and to establish their relationship with Victorian Institute of Sport Assessment-Patella (VISA-P) scores in a group of volleyball players with and without symptoms of patellar tendinopathy. Cross-sectional study. Thirty-five volleyball players (70 patellar tendons) were recruited during a national university volleyball competition. Players were imaged with conventional US followed by elastography. The clinical findings of painful patellar tendons were used as the reference standard for diagnosing patellar tendinopathy. In addition, all participants completed the VISA-P questionnaires. Of the 70 patellar tendons, 40 (57.1%) were clinically painful. The diagnostic accuracy of grey scale US, PD and elastography were 60%, 50%, 62.9%, respectively, with sensitivity/specificity of 72.5%/43.3%, 12.5%/100%, and 70%/53.3%, respectively. Combined US elastography and grey scale imaging achieved 82.5% sensitivity, 33.3% specificity and 61.4% accuracy while routine combination technique of PD and grey scale imaging revealed 72.5% sensitivity, 43.3% specificity and 60.0% accuracy. Tendons in players categorized as soft on elastography had statistically significantly greater AP thickness (p<0.001) and lower VISA-P scores (p=0.004) than those categorized as hard. There was no significant association between grey scale US abnormalities (hypoechogenicities and/or fusiform swelling) and VISA-P scores (p=0.098). Soft tendon properties depicted by US elastography may be more related to patellar tendon symptoms compared to grey scale US abnormalities. The supplementation of US elastography to conventional US may enhance the sensitivity for diagnosing patellar tendinopathy in routine clinical practice. Copyright © 2015 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  8. [Physiopathology of superficial venous circulation in athletes].

    Science.gov (United States)

    Venerando, A; Pelliccia, A

    1981-01-01

    The venous circulation in athletes doing sports involving medium or heavy cardiac strain means that considerable physiological modifications may occur, notably vascular expansion. This phenomenon may be observed in the superficial venous circulation of both the upper and lower members, as well as in pulmonary circulation. Varices of the lower members are common in about 5% of practising athletes, notably in weight-lifters and wrestlers who are particularly prone to this risk, and precisely because venous return is impeded by the predominantly static effort which characterizes these sports. Karate, judo, canoeing, football, high jump and long jump are similar: mechanical blocks or sudden increases of venous pressure following the rapid changes in body-position or particular posture. Nevertheless, these phenomena can only be explained by the supposition that the valvular mechanism of certain subjects is particularly vulnerable. There are other sports, on the other hand, which have a beneficial effect on venous return, especially swimming and long-distance running.

  9. The usefulness of strain wave elastography in the diagnosis and grading of Hashimoto's thyroiditis in children.

    Science.gov (United States)

    Öztürk, Mehmet; Yildirim, Ruken

    2017-12-01

    This study aimed to evaluate the efficacy of Elastographic Strain Index (SI) in the diagnosis and grading of pediatric Hashimoto's thyroiditis (HT) patients. This cross-sectional, controlled trial was carried out in the pediatric radiology department of our tertiary care center. The study group consisted of 63 children with HT and control group was composed of 47 healthy children. Conventional ultrasonography (US) and SI elastography measurements were performed through the Aplio™ 500 ultrasonic device with a linear 4.8-11.0 MHz transducer and elastography software. Furthermore, the correlation between strain ratio values and other variables was investigated. The mean age of the HT patients was 139.63 ± 27.61 months, and no significant difference was found between the control group (143.09 ± 27.32 months) and the patients regarding mean age and gender. The mean SI of normal healthy individuals and patients with HT was 0.26 ± 0.77 and 1.75 ± 1.46, respectively (p < 0.001). For the diagnosis for HT with elastography, the sensitivity was 92.1%, and specificity was 66% when the optimal mean SI cut-off value was taken as 0.31, (p < 0.001). The use of elastographic SI in patients with HT is a highly promising method for objective and countable results compared with the conventional US. The sensitivity of the increase in SI value was determined to be high in the diagnosis of HT. It was also considered that the elastography SI value had higher sensitivity and specificity than the conventional US in HT patients with moderate to advanced tissue hardening.

  10. Real-time Tissue Elastography for Assessment of Liver Stiffness in Adults Without Known Liver Disease.

    Science.gov (United States)

    Hu, Yu; Gong, Hai-Yan; Lin, Hong-Jun

    2015-10-01

    To investigate normal liver stiffness and its influential factors in adults without liver disease using real-time tissue elastography. The liver stiffness threshold value for identifying patients with chronic liver disease was also determined. One hundred twenty healthy volunteers were examined with real-time tissue elastography. An integrated quantitative elastographic parameter, defined as the liver fibrosis index, was obtained by tissue dispersion quantitative analysis. Correlations between the liver fibrosis index and age, sex, and body mass index (BMI) were studied. To determine the threshold value for identifying chronic liver disease, 29 patients with chronic hepatitis B who underwent liver biopsy, including patients without fibrosis (fibrosis stage F0; n = 9) and patients with substantial fibrosis (F1-F2; n = 20) were also investigated. A receiver operating characteristic curve analysis for differentiating the F0 from the F1-F2 group was performed. There were no significant differences in the mean liver fibrosis index between sexes or among different age groups. There was a positive correlation between BMI and the liver fibrosis index. The mean liver fibrosis index ± SD in healthy participants with a normal BMI was 1.31 ± 0.25. The mean liver fibrosis index values for F0 and F1-F2 patients with a normal BMI were 1.47 ± 0.24 and 2.44 ± 0.49, respectively (P liver fibrosis index threshold value for discriminating normal liver from noncirrhotic chronic liver disease was 2.12 in participants with a normal BMI. Liver stiffness determined by real-time tissue elastography in healthy Chinese adults is not affected by age and sex but has a positive correlation with BMI. Real-time tissue elastography for assessment of liver stiffness can also be used for identification of substantial fibrosis in patients with chronic liver disease. © 2015 by the American Institute of Ultrasound in Medicine.

  11. The Shear Wave Velocity on Elastography Correlates with the Clinical Symptoms and Histopathological Features of Keloids

    OpenAIRE

    Aya, Rino; Yamawaki, Satoko; Yoshikawa, Katsuhiro; Katayama, Yasuhiro; Enoshiri, Tatsuki; Naitoh, Motoko; Suzuki, Shigehiko

    2015-01-01

    Background: Keloids present as red, painful lesions causing serious functional and cosmetic problems; however, there is no consensus regarding tools for objectively evaluating keloids. To demonstrate the utility of shear wave elastography in keloids, we investigated the correlations between clinical symptoms, ultrasound shear wave velocity, and histopathological findings. Methods: Three patients with keloids containing both red hypertrophic and mature areas were evaluated using the shear wave...

  12. Evaluation of large esophageal varices in cirrhotic patients by transient elastography: a meta-analysis

    Directory of Open Access Journals (Sweden)

    Tao Li

    Full Text Available Background and purpose: Transient elastography (TE has been shown to be a valuable tool for the prediction of large esophageal varices. However, the conclusions have not been always consistent throughout the different studies. Therefore, we performed a further meta-analysis in order to evaluate the diagnostic accuracy of transient elastography for the prediction of large esophageal varices. Methods: We performed a systematic literature search in PubMed, EMBASE, Web of Science, and CENTRAL in The Cochrane Library without time restriction. The strategy we used was "(fibroscan OR transient elastography OR stiffness AND esophageal varices". Accuracy measures such as pooled sensitivity, specificity, among others, were calculated using Meta-DiSc statistical software. Results: Twenty studies (2,994 patients were included in our meta-analysis. The values of pooled sensitivity, specificity, positive and negative likelihood ratios and diagnostic odds ratio were as follows: 0.81 (95% CI, 0.79-0.84, 0.71 (95% CI, 0.69-0.73, 2.63 (95% CI, 2.15-3.23, 0.27 (95% CI, 0.22-0.34 and 10.30 (95% CI, 7.33-14.47. The area under the receiver operating characteristics curve was 0.83. The Spearman correlation coefficient was 0.246 with a p-value of 0.296, indicating the absence of any significant threshold effects. In our subgroup analysis, the heterogeneity could be partially explained by the geographical origin of the study or etiology; or it could be partially explained blindingly, through the appropriate interval and cut-off value of the liver stiffness (LS. Conclusions: Transient elastography could be used as a valuable non-invasive screening tool for the prediction of large esophageal varices. However, since LS cut-off values vary throughout the different studies and significant heterogeneity also exists among them, we need more reasonable approaches or flow diagram in order to improve the operability of this technology.

  13. Shear wave elastography and parathyroid adenoma: A new tool for diagnosing parathyroid adenomas.

    Science.gov (United States)

    Azizi, Ghobad; Piper, Kelé; Keller, James M; Mayo, Michelle L; Puett, David; Earp, Karly M; Malchoff, Carl D

    2016-09-01

    This study prospectively determines the shear wave elastography characteristics of parathyroid adenomas using virtual touch imaging quantification, a non-invasive ultrasound based shear wave elastography method. This prospective study examined 57 consecutive patients with biochemically proven primary hyperparathyroidism and solitary parathyroid adenoma identified by ultrasound and confirmed by at least one of the following: surgical resection, positive Technetium-99m Sestamibi Scintigraphy (MIBI) scan, or fine needle aspiration biopsy with positive PTH washout (performed only in MIBI negative patients). Vascularity and shear wave elastography were performed for all patients. Parathyroid adenoma stiffness was measured as shear wave velocity in meters per second. The median (range) pre-surgical value for PTH and calcium were 58pg/mL (19, 427) and 10.8mg/dL (9.5, 12.1), respectively. 37 patients had positive MIBI scan. 20 patients had negative MIBI scan but diagnosis was confirmed with positive PTH washout. 42 patients underwent parathyroidectomy, and an adenoma was confirmed in all. The median (range) shear wave velocity for all parathyroid adenomas enrolled in this study was 2.02m/s (1.53, 2.50). The median (range) shear wave velocity for thyroid tissue was 2.77m/s (1.89, 3.70). The shear wave velocity of the adenomas was independent of adenoma size, serum parathyroid hormone concentration, or plasma parathyroid hormone concentration. Tissue elasticity of parathyroid adenoma is significantly lower than thyroid tissue. B-mode features and distinct vascularity pattern are helpful tools in diagnosing parathyroid adenoma with ultrasound. Shear wave elastography may provide valuable information in diagnosing parathyroid adenoma. Copyright © 2016 The Author(s). Published by Elsevier Ireland Ltd.. All rights reserved.

  14. The Development of Vibration System for Applying Magnetic Resonance Elastography (MRE) to the Supraspinatus Muscle

    OpenAIRE

    伊東, 大輝; 沼野, 智一; 水原, 和行; 高本, 考一; 大西, 孝明; 西条, 寿夫

    2016-01-01

    Palpation is a standard clinical tool to diagnose abnormal stiffness changes in soft tissues. However, it is difficult to palpate the supraspinatus muscle because it locates under the trapezius muscle. The magnetic resonance elastography (MRE) uses harmonic mechanical excitation to quantitatively measure the stiffness (shear modulus) of both the superficial and deep tissues. The purpose of this study was to build a vibration system for applying the MRE to the supraspinatus muscle. In this stu...

  15. Slip interface imaging based on MR‐elastography preoperatively predicts meningioma–brain adhesion

    OpenAIRE

    Yin, Ziying; Hughes, Joshua D.; Glaser, Kevin J.; Manduca, Armando; Van Gompel, Jamie; Link, Michael J.; Romano, Anthony; Ehman, Richard L.; Huston, John

    2017-01-01

    Purpose To investigate the ability of slip interface imaging (SII), a recently developed magnetic resonance elastography (MRE)‐based technique, to predict the degree of meningioma–brain adhesion, using findings at surgery as the reference standard. Materials and Methods With Institutional Review Board approval and written informed consent, 25 patients with meningiomas >2.5 cm in maximal diameter underwent preoperative SII assessment. Intracranial shear motions were introduced using a soft, pi...

  16. Update on Breast Cancer Detection Using Comb-push Ultrasound Shear Elastography

    OpenAIRE

    Denis, Max; Bayat, Mahdi; Mehrmohammadi, Mohammad; Gregory, Adriana; Song, Pengfei; Whaley, Dana H; Pruthi, Sandhya; Chen, Shigao; Fatemi, Mostafa; Alizad, Azra

    2015-01-01

    In this work, tissue stiffness estimates are used to differentiate between benign and malignant breast masses in a group of pre-biopsy patients. The rationale being that breast masses are often stiffer than healthy tissue; furthermore, malignant masses are stiffer than benign masses. The comb-push ultrasound shear elastography (CUSE) method is used to noninvasively assess a tissue’s mechanical properties. CUSE utilizes a simultaneous multiple laterally spaced radiation force (ARF) excitations...

  17. Breast ultrasound elastography-Results of 193 breast lesions in a prospective study with histopathologic correlation

    Energy Technology Data Exchange (ETDEWEB)

    Schaefer, F.K.W., E-mail: fschaefer@email.uni-kiel.de [Breast Centre, University Hospital Schleswig-Holstein Campus Kiel, Arnold-Heller-Str. 3/Haus 24, 24105 Kiel (Germany); Heer, I.; Schaefer, P.J.; Mundhenke, C.; Osterholz, S.; Order, B.M.; Hofheinz, N.; Hedderich, J.; Heller, M.; Jonat, W.; Schreer, I. [Breast Centre, University Hospital Schleswig-Holstein Campus Kiel, Arnold-Heller-Str. 3/Haus 24, 24105 Kiel (Germany)

    2011-03-15

    Purpose: To evaluate the diagnostic performance of ultrasound elastography in breast masses. Material and methods: 193 lesions (129 benign, 64 malignant) were analyzed with the EUB 8500 Logos-ultrasonic-unit (Hitachi Medical, Japan) and a linear-array-transducer of 7.5-13-MHz. Standard of reference was cytology (FNAfine needle aspiration) or histology (core biopsy). The elastic-score was classified according to a 6-point colour-scale (Ueno classification; 1-3 = benign, 4-5 = malignant). Conventional B-mode ultrasound (US) findings were classified according to the BI-RADS classification. Statistical analysis included sensitivity, specificity, ROC-analysis and kappa-values for intra-/interobserver reliability. Results: The mean score for elasticity was 4.1 {+-} 0.9 for malignant lesions, and 2.1 {+-} 1.0 for benign lesions (p < 0.001). With a best cut-off point between elasticity scores 3 and 4, sensitivity was 96.9%, and specificity 76%. Setting a best cut-off point for conventional US between BI-RADS 4 and 5, sensitivity was 57.8%, and specificity 96.1%. Elastography provided higher sensitivity and lower specificity than conventional US, but two lesions with elasticity score 1 were false negative, whereas no lesion scored BI-RADS 1-3 were false negative. ROC-curve was 0.884 for elastography, and 0.820 for conventional US (p < 0.001). Weighted kappa-values for intra-/interobserver reliability were 0.784/0.634 for BI-RADS classification, and 0.720/0.561 for elasticity scores. Conclusion: In our study setting, elastography does not have the potential to replace conventional B-mode US for the detection of breast cancer, but may complement conventional US to improve the diagnostic performance.

  18. Postpartum venous thromboembolism: incidence and risk factors.

    Science.gov (United States)

    Tepper, Naomi K; Boulet, Sheree L; Whiteman, Maura K; Monsour, Michael; Marchbanks, Polly A; Hooper, W Craig; Curtis, Kathryn M

    2014-05-01

    To calculate incidence of postpartum venous thromboembolism by week after delivery and to examine potential risk factors for venous thromboembolism overall and at different times during the postpartum period. A deidentified health care claims information database from employers, health plans, hospitals, and Medicaid programs across the United States was used to identify delivery hospitalizations among women aged 15-44 years during the years 2005-2011. International Classification of Diseases, 9th Revision, Clinical Modification diagnosis and procedure codes were used to identify instances of venous thromboembolism and associated characteristics and conditions among women with recent delivery. Incidence proportions of venous thromboembolism by week postpartum through week 12 were calculated per 10,000 deliveries. Logistic regression was used to calculate odds ratios for selected risk factors among women with postpartum venous thromboembolism and among women with venous thromboembolism during the early or later postpartum periods. The incidence proportion of postpartum venous thromboembolism was highest during the first 3 weeks after delivery, dropping from nine per 10,000 during the first week to one per 10,000 at 4 weeks after delivery and decreasing steadily through the 12th week. Certain obstetric procedures and complications such as cesarean delivery, preeclampsia, hemorrhage, and postpartum infection conferred an increased risk for venous thromboembolism (odds ratios ranging from 1.3 to 6.4), which persisted over the 12-week period compared with women without these risk factors. Risk for postpartum venous thromboembolism is highest during the first 3 weeks after delivery. Women with obstetric complications are at highest risk for postpartum venous thromboembolism, and this risk remains elevated throughout the first 12 weeks after delivery. II.

  19. Venous hemodynamic changes in lower limb venous disease

    DEFF Research Database (Denmark)

    Lee, Byung Boong; Nicolaides, Andrew N; Myers, Kenneth

    2016-01-01

    There are excellent guidelines for clinicians to manage venous diseases but few reviews to assess their hemodynamic background. Hemodynamic concepts that evolved in the past have largely remained unchallenged in recent decades, perhaps due to their often complicated nature and in part due...... not provide the physiological basis for understanding the hemodynamics of flow, pressure, compliance and resistance. Hemodynamic investigations appear to provide a better correlation with post-treatment clinical outcome and quality of life than ultrasound findings. There is a far better prospect...... for understanding the complete picture of the patient's disability and response to management by combining ultrasound with hemodynamic studies. Accordingly, at the instigation of Dr Angelo Scuderi, the Union Internationale de Phlebologie (UIP) executive board commissioned a large number of experts to assess all...

  20. Effect of postthrombotic syndrome on health-related quality of life after deep venous thrombosis.

    Science.gov (United States)

    Kahn, Susan R; Hirsch, Andrew; Shrier, Ian

    2002-05-27

    Postthrombotic syndrome (PTS) is a frequent chronic complication of deep venous thrombosis, yet its impact on health-related quality of life has not been well characterized. We compared generic and venous disease-specific quality of life in patients with and without PTS, and assessed whether quality of life correlated with severity of PTS. Subjects with previous deep venous thrombosis were participants in a study of the effects of exercise after deep venous thrombosis. We ascertained PTS and its severity using a validated clinical scale. Subjects completed generic (the 36-Item Short-Form Health Survey) and disease-specific (Venous Insufficiency Epidemiologic and Economic Study quality-of-life questionnaire [VEINES-QOL] and its validated subscale of 10 items on venous symptoms [VEINES-Sym]) quality-of-life measures. Age- and sex-adjusted mean quality-of-life scores were compared in patients with and without PTS, and by severity of PTS. Of the 41 subjects (mean age, 51.2 years), 19 (46%) had PTS. Subjects with PTS had significantly worse disease-specific quality-of-life scores than those without PTS (mean +/- SD VEINES-QOL score, 44.5 +/- 11.6 vs 54.8 +/- 5.4, respectively [Pdisease-specific quality of life that may not be captured by generic quality-of-life measures. Patient-based quality-of-life measures correlated well with physician-assessed PTS. Further research is indicated to assess the value of including quality of life as a routine measure of outcome in clinical studies of patients with deep venous thrombosis and PTS.

  1. Ultrasound elastography of the supraspinatus tendon guided by US-MRI virtual navigation.

    Science.gov (United States)

    Liu, Jun; Zhan, Weiwei; Zhou, Mingyang; Zhang, Xiaoxiao

    2015-01-01

    A virtual navigation system (VNS) can combine two imaging modalities for synchronous observation and can be beneficial for diagnosis and treatment. Ultrasound elastography (UE) can distinguish between soft and hard tissues. However, the application of UE to musculoskeletal structures is rare. To evaluate UE of the supraspinatus tendon using ultrasound-magnetic resonance imaging (US-MRI) virtual navigation. Sixty patients with an ache in the shoulder were diagnosed with supraspinatus tendon injuries using MRI. US-MRI virtual navigation was used to identify lesions in the supraspinatus tendon, and finally US elastography (UE) was performed. Volunteers whose supraspinatus tendons were diagnosed as normal by MRI were also selected for US elastography. The UE scores were then compared between patients and volunteers. A total of 60 patients were diagnosed with supraspinatus tendon injuries using MRI and forty-two patients classified as Grade I exhibited no obvious abnormality by US. The supraspinatus tendon injury scores were significantly higher in Grade I patients compared with volunteers (Pvirtual navigation.

  2. A review of the natural history of chronic hepatitis B in the era of transient elastography.

    Science.gov (United States)

    Chan, Henry Lik-Yuen; Wong, Grace Lai-Hung; Wong, Vincent Wai-Sun

    2009-01-01

    Understanding the natural history of chronic hepatitis B is important in order to predict the prognosis, to stratify the risk of hepatocellular carcinoma and to select appropriate candidates for antiviral treatment. Liver fibrosis is the pathogenic process that leads to liver cirrhosis. The study of liver fibrosis in the past has largely been hampered by the invasive nature of a liver biopsy. Most liver biopsy series represent biased populations with more active disease. Transient elastography is a reliable and non-invasive measurement of liver fibrosis that allows the study of liver fibrosis among patients without clinical indication for liver biopsy. Large studies using transient elastography in patients with predominantly normal alanine aminotransferase levels have been reported recently. The different roles of patient age, hepatitis B virus DNA and alanine aminotransferase levels in the risk stratification for advanced liver fibrosis have been defined in hepatitis B e antigen-positive and hepatitis B e antigen-negative chronic hepatitis B patients. The relationship between metabolic syndrome and chronic hepatitis B is also explored. In this review, new insights from studies using transient elastography on the natural history of chronic hepatitis B with special focus on liver fibrosis will be summarized and discussed.

  3. Application of Ultrasound Elastography for Chronic Allograft Dysfunction in Kidney Transplantation.

    Science.gov (United States)

    Wang, Zijie; Yang, Haiwei; Suo, Chuanjian; Wei, Jifu; Tan, Ruoyun; Gu, Min

    2017-09-01

    Interstitial fibrosis is the main characteristic of chronic allograft dysfunction, which remains the key factor affecting long-term allograft survival after kidney transplantation. Ultrasound elastography (UE), including real-time elastography, transient elastography, and acoustic radiation force impulse, has been applied widely in breast, thyroid, and liver diseases, especially in the assessment of liver fibrosis. Recently, numerous studies have reported the efficacy of UE methods in evaluating renal allograft fibrosis. This review aims to investigate the clinical applications, limitations, and future roles of UE in current clinical practice in light of changing management paradigms. In current clinical practice, UE methods, especially transient elastographic measurement, appear to be useful for ruling out fibrosis but do not have sufficient accuracy to distinguish between various stages of allograft fibrosis. Moreover, there remain considerable issues to be solved for the application of UE in kidney transplantation. Thus, UE methods cannot replace the crucial role of renal allograft biopsy in the diagnosis and evaluation of allograft fibrosis in kidney transplantation. Perhaps UE methods could be of more importance in the long-term observation and evaluation of allograft fibrosis during follow-up. © 2017 by the American Institute of Ultrasound in Medicine.

  4. A hybrid CPU-GPGPU approach for real-time elastography.

    Science.gov (United States)

    Yang, Xu; Deka, Sthiti; Righetti, Raffaella

    2011-12-01

    Ultrasound elastography is becoming a widely available clinical imaging tool. In recent years, several real- time elastography algorithms have been proposed; however, most of these algorithms achieve real-time frame rates through compromises in elastographic image quality. Cross-correlation- based elastographic techniques are known to provide high- quality elastographic estimates, but they are computationally intense and usually not suitable for real-time clinical applications. Recently, the use of massively parallel general purpose graphics processing units (GPGPUs) for accelerating computationally intense operations in biomedical applications has received great interest. In this study, we investigate the use of the GPGPU to speed up generation of cross-correlation-based elastograms and achieve real-time frame rates while preserving elastographic image quality. We propose and statistically analyze performance of a new hybrid model of computation suitable for elastography applications in which sequential code is executed on the CPU and parallel code is executed on the GPGPU. Our results indicate that the proposed hybrid approach yields optimal results and adequately addresses the trade-off between speed and quality.

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

    Science.gov (United States)

    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.

  6. Ultrasound elastography and contrast-enhanced ultrasound in infants, children and adolescents

    Energy Technology Data Exchange (ETDEWEB)

    Stenzel, Martin, E-mail: martin.stenzel@med.uni-jena.de; Mentzel, Hans-Joachim

    2014-09-15

    Objective: To describe prerequisites, use, and safety of ultrasound elastography and contrast-enhanced ultrasound in infants, children, and adolescents. Method: This review deals with two latest developments in ultrasonography in children. The principle of strain elastography, transient elastography, and acoustic radiation force imaging is discussed, including limitations, and advantages of the different techniques in diagnosing focal and diffuse organ disease. The intravesical (contrast-enhanced voiding ultrasonography) and intravascular use of contrast-media to outline blood, and urinary flow is described, with special emphasis on indications, off-label use, and diagnostic gain. Examples of indications for performing the advanced ultrasound techniques are presented. Summary and conclusion: Latest developments in ultrasound machine engineering, and the availability of contrast-media that interact with ultrasound waves allow for assessment of tissue stiffness/elasticity properties, blood, and urinary flow. Thereby ultrasound is capable not only to depict morphology, but gives the additional information on organ, and focal lesion perfusion, and urinary flow dynamics. The information gap to other cross-sectional techniques such as magnetic resonance imaging, that make potential harmful sedation, and anaesthesia in the youngest children necessary, thereby gets closer.

  7. Effects of compression force on elasticity index and elasticity ratio in ultrasound elastography

    Science.gov (United States)

    Sasaki, Y; Sakamoto, J; Kamio, T; Nishikawa, K; Otonari-Yamamoto, M; Wako, M

    2014-01-01

    Objectives: The purpose of this study was to investigate the relationship between compression force and hardness values in ultrasound elastography. Methods: Ultrasound elastography was performed using an elastography phantom, comprising inclusions with different elasticities and echogenicities. The compression force was set to approximately 100 gw (light force) and approximately 500 gw (heavy force). The elasticity index (EI) of the inclusion was measured. The EI was a relative hardness value of a structure within an elastographic image. Similarly, the EI of the background was measured as a reference. The elasticity ratio (ER) was calculated as the EI of the inclusion divided by the EI of the reference. Results: The hardness of the phantom could be discerned with both the EI and ER, regardless of the compression force. The EI and ER with heavy force tended to be higher than those with light force, but the difference was not significant. A strong correlation was observed between the EI and ER of soft structures, whereas the correlation between the EI and ER of hard structures was weak, and the ER values varied widely. Conclusions: The EI offers potential as a good indicator for assessing the hardness. PMID:24592929

  8. Evaluation of Neoadjuvant Chemotherapy Response in Women with Locally Advanced Breast Cancer Using Ultrasound Elastography1

    Science.gov (United States)

    Falou, Omar; Sadeghi-Naini, Ali; Prematilake, Sameera; Sofroni, Ervis; Papanicolau, Naum; Iradji, Sara; Jahedmotlagh, Zahra; Lemon-Wong, Sharon; Pignol, Jean-Philippe; Rakovitch, Eileen; Zubovits, Judit; Spayne, Jacqueline; Dent, Rebecca; Trudeau, Maureen; Boileau, Jean Francois; Wright, Frances C; Yaffe, Martin J; Czarnota, Gregory J

    2013-01-01

    PURPOSE: Ultrasound elastography is a new imaging technique that can be used to assess tissue stiffness. The aim of this study was to investigate the potential of ultrasound elastography for monitoring treatment response of locally advanced breast cancer patients undergoing neoadjuvant therapy. METHODS: Fifteen women receiving neoadjuvant chemotherapy had the affected breast scanned before, 1, 4, and 8 weeks following therapy initiation, and then before surgery. Changes in elastographic parameters related to tissue biomechanical properties were then determined and compared to clinical and pathologic tumor response after mastectomy. RESULTS: Patients who responded to therapy demonstrated a significant decrease (P < .05) in strain ratios and strain differences 4 weeks after treatment initiation compared to non-responding patients. Mean strain ratio and mean strain difference for responders was 81 ± 3% and 1 ± 17% for static regions of interest (ROIs) and 81 ± 3% and 6 ± 18% for dynamic ROIs, respectively. In contrast, these parameters were 102±2%, 110±17%, 101±4%, and 109±30% for non-responding patients, respectively. Strain ratio using static ROIs was found to be the best predictor of treatment response, with 100% sensitivity and 100% specificity obtained 4 weeks after starting treatment. CONCLUSIONS: These results suggest that ultrasound elastography can be potentially used as an early predictor of tumor therapy response in breast cancer patients. PMID:23418613

  9. Evaluation of neoadjuvant chemotherapy response in women with locally advanced breast cancer using ultrasound elastography.

    Science.gov (United States)

    Falou, Omar; Sadeghi-Naini, Ali; Prematilake, Sameera; Sofroni, Ervis; Papanicolau, Naum; Iradji, Sara; Jahedmotlagh, Zahra; Lemon-Wong, Sharon; Pignol, Jean-Philippe; Rakovitch, Eileen; Zubovits, Judit; Spayne, Jacqueline; Dent, Rebecca; Trudeau, Maureen; Boileau, Jean Francois; Wright, Frances C; Yaffe, Martin J; Czarnota, Gregory J

    2013-02-01

    Ultrasound elastography is a new imaging technique that can be used to assess tissue stiffness. The aim of this study was to investigate the potential of ultrasound elastography for monitoring treatment response of locally advanced breast cancer patients undergoing neoadjuvant therapy. Fifteen women receiving neoadjuvant chemotherapy had the affected breast scanned before, 1, 4, and 8 weeks following therapy initiation, and then before surgery. Changes in elastographic parameters related to tissue biomechanical properties were then determined and compared to clinical and pathologic tumor response after mastectomy. Patients who responded to therapy demonstrated a significant decrease (P < .05) in strain ratios and strain differences 4 weeks after treatment initiation compared to non-responding patients. Mean strain ratio and mean strain difference for responders was 81 ± 3% and 1 ± 17% for static regions of interest (ROIs) and 81 ± 3% and 6 ± 18% for dynamic ROIs, respectively. In contrast, these parameters were 102±2%, 110±17%, 101±4%, and 109±30% for non-responding patients, respectively. Strain ratio using static ROIs was found to be the best predictor of treatment response, with 100% sensitivity and 100% specificity obtained 4 weeks after starting treatment. These results suggest that ultrasound elastography can be potentially used as an early predictor of tumor therapy response in breast cancer patients.

  10. Slip elastography: a novel method for visualising and characterizing adherence between two surfaces in contact.

    Science.gov (United States)

    Chakraborty, Aabir; Bamber, Jeffrey C; Dorward, Neil L

    2012-03-01

    Identification of the anatomical location and mechanical properties such as adherence at the tissue tumour interface may be of clinical benefit in determination of tumour resectability and prognosis. There are currently no imaging modalities in routine clinical practice that can provide this information. This paper presents the development of a new imaging technique based on ultrasound elastography, called slip elastography, for determination of the anatomical location and measurement of the adherence between two surfaces. The theoretical basis of slip and its definition in relation to shear are described. In vitro testing with gelatine phantoms to determine the optimal parameters for shear strain estimation and slip boundary measurement and to test reliability are also described. The results suggest that slip elastography can reliably identify the anatomical location of a slip boundary and can measure the externally applied axial force required to initiate slip at that boundary in vitro. The vector based shear strain estimator was the most robust and worked with minimal angular dependence with minimal non-slip shearing artefact. Copyright © 2011 Elsevier B.V. All rights reserved.

  11. Value of liver elastography and abdominal ultrasound for detection of complications of allogeneic hemopoietic SCT.

    Science.gov (United States)

    Karlas, T; Weber, J; Nehring, C; Kronenberger, R; Tenckhoff, H; Mössner, J; Niederwieser, D; Tröltzsch, M; Lange, T; Keim, V

    2014-06-01

    Hepatic complications contribute to morbidity and mortality after allogeneic hemopoietic SCT. Liver Doppler ultrasound and elastography represent promising methods for pretransplant risk assessment and early detection of complications. Ultrasound (liver and spleen size, liver perfusion) and elastography (transient elastography (TE); right liver lobe acoustic radiation force impulse imaging (r-ARFI); left liver lobe ARFI (l-ARFI)) were prospectively evaluated in patients with indications for allo-SCT. Measurements were performed before and repeatedly after SCT. Results were compared with the incidence of life-threatening complications and death during the first 150 days after SCT. Of 59 included patients, 16 suffered from major complications and 9 of them died within the follow-up period. At baseline, liver and spleen size, liver perfusion, TE and r-ARFI did not differ significantly between patients with and without severe complications. In contrast, l-ARFI was significantly elevated in patients who later developed severe complications (1.58±0.30 m/s vs 1.37±0.27 m/s, P=0.030). After SCT, l-ARFI values remained elevated and TE showed increasing liver stiffness in patients with complications. The value of conventional liver ultrasound for prediction of severe SCT complications is limited. Increased values for TE and l-ARFI are associated with severe SCT complications and demand further evaluation.

  12. Assessment of placental stiffness using acoustic radiation force impulse elastography in pregnant women with fetal anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Alan, Bircan; Goya, Cemil; Tunc, Senem; Teke, Memik; Hattapoglu, Salih [Dicle University Medical Faculty, Diyarbakir (Turkmenistan)

    2016-04-15

    We aimed to evaluate placental stiffness measured by acoustic radiation force impulse (ARFI) elastography in pregnant women in the second trimester with a normal fetus versus those with structural anomalies and non-structural findings. Forty pregnant women carrying a fetus with structural anomalies diagnosed sonographically at 18-28 weeks of gestation comprised the study group. The control group consisted of 34 healthy pregnant women with a sonographically normal fetus at a similar gestational age. Placental shear wave velocity (SWV) was measured by ARFI elastography and compared between the two groups. Structural anomalies and non-structural findings were scored based on sonographic markers. Placental stiffness measurements were compared among fetus anomaly categories. Doppler parameters of umbilical and uterine arteries were compared with placental SWV measurements. All placental SWV measurements, including minimum SWV, maximum SWV, and mean SWV were significantly higher in the study group than the control group ([0.86 ± 0.2, 0.74 ± 0.1; p < 0.001], [1.89 ± 0.7, 1.59 ± 0.5; p = 0.04], and [1.26 ± 0.4, 1.09 ± 0.2; p = 0.01]), respectively. Placental stiffness evaluated by ARFI elastography during the second trimester in pregnant women with fetuses with congenital structural anomalies is higher than that of pregnant women with normal fetuses.

  13. Object detection in ultrasound elastography for use in HIFU treatment of cancer

    Science.gov (United States)

    Huang, Alex; Mankani, Soumya; Choo, Chang

    2014-03-01

    High intensity focused ultrasound (HIFU), has applications in treating various cancers, such as prostate, liver and breast cancer. In order for HIFU to be effective and efficient it needs to be guided by an imaging modality. While there are several options for guiding HIFU treatment, one of the most promising is ultrasound elastography. Current commercial devices use Brightness-Mode (B-mode) imaging or MRI, and are manual processes. Ultrasound elastography, allows complete automation of HIFU treatment due to the enhanced image, that elastography provides. The elastic image provides more information and less noise. To show that segmentation was possible on elastic images, nine algorithms were implemented in matlab and used on three distinct images for object detection. The three images used, have varying properties regarding object intensity and placement, as well as different noise patterns. Using PSNR, to gauge the effectiveness of each algorithm, it was shown that segmentation was possible on all images using different algorithms. The bilateral-shock-bilateral algorithm proved to be an overall effective algorithm in every situation with a PSNR of 83.87db on the phantom image. The segmentation results clearly highlight any object in the images. Future work includes fine tuning the algorithm with different phantom images and in-vivo images to distinguish between noise and desired object.

  14. Association of Traditional Cardiovascular Risk Factors with Venous Thromboembolism

    DEFF Research Database (Denmark)

    Mahmoodi, Bakhtawar K; Cushman, Mary; Næss, Inger Anne

    2017-01-01

    Background: Much controversy surrounds the association of traditional cardiovascular disease risk factors with venous thromboembolism (VTE). Methods: We performed an individual level random-effect meta-analysis including 9 prospective studies with measured baseline cardiovascular disease risk...... factors and validated VTE events. Definitions were harmonized across studies. Traditional cardiovascular disease risk factors were modeled categorically and continuously using restricted cubic splines. Estimates were obtained for overall VTE, provoked VTE (ie, VTE occurring in the presence of 1 or more...... is potentially mediated through comorbid conditions such as cancer, the modifiable traditional cardiovascular disease risk factors are not associated with increased VTE risk. Higher systolic blood pressure showed an inverse association with VTE....

  15. Role of central venous pressure monitoring in critical care settings.

    Science.gov (United States)

    Thomas Hill, Barry

    2018-01-31

    Central venous pressure (CVP) monitoring is used to assess the fluid status of patients in critical care settings. This article explains CVP monitoring, discussing the rationale for its use, the ways CVP can be measured, and the physiological factors that can affect the reliability and validity of CVP measurement. It also discusses the complications associated with CVP monitoring and the nursing responsibilities in relation to this activity. ©2018 RCN Publishing Company Ltd. All rights reserved. Not to be copied, transmitted or recorded in any way, in whole or part, without prior permission of the publishers.

  16. Performance Characteristics of Vibration-Controlled Transient Elastography for Evaluation of Non-Alcoholic Fatty Liver Disease.

    Science.gov (United States)

    Vuppalanchi, Raj; Siddiqui, Mohammad S; Van Natta, Mark L; Hallinan, Erin; Brandman, Danielle; Kowdley, Kris; Neuschwander-Tetri, Brent A; Loomba, Rohit; Dasarathy, Srinivas; Abdelmalek, Manal; Doo, Edward; Tonascia, James A; Kleiner, David E; Sanyal, Arun J; Chalasani, Naga

    2017-08-31

    Vibration-controlled transient elastography (VCTE) estimates liver stiffness measurement (LSM) and controlled attenuation parameter (CAP) which are noninvasive assessments of hepatic fibrosis and steatosis respectively. However, prior VCTE studies reported high failure rate in patients with non-alcoholic fatty liver disease (NAFLD). To examine the performance characteristics of Fibroscan 502 Touch with two probes, medium (M+) and extra-large (XL+), in patients with NAFLD in a multicenter setting. A total of 1696 exams were attempted in 992 patients (BMI: 33.6 ± 6.5 kg/m(2) ) with histologically confirmed NAFLD. Simultaneous assessment of LSM and CAP was performed using Fibroscan 502 Touch with an automatic probe selection tool. Testing was conducted twice in patients by either a single operator (88%) or two operators (12%). Failure was defined as the inability to obtain a valid examination. An examination was considered unreliable if LSM IQR/median was >30%. Significant disagreement between two readings was defined as greater than >95% limits of agreement between two readings. A total of 1641 examinations yielded valid results with a failure rate of 3.2% (55/1696). The proportion of unreliable scans for LSM was 2.4%. The proportion of unreliable scans with operator experience in the top quartile (≥ 59 procedures) was significantly lower than lower three quarters combined (1.6% vs.4.7%, p=0.01 by Fisher's Exact test). The significant disagreement between first and second readings for LSM and CAP when obtained back to back was 18% and 11% respectively. VCTE for estimation of LSM and CAP can be successfully deployed in a multicenter setting with low failure (3.2%) and high reliability (>95%) rates and high reproducibility. This article is protected by copyright. All rights reserved. © 2017 by the American Association for the Study of Liver Diseases.

  17. Quantification of elastic heterogeneity using contourlet-based texture analysis in shear-wave elastography for breast tumor classification.

    Science.gov (United States)

    Zhang, Qi; Xiao, Yang; Chen, Shuai; Wang, Congzhi; Zheng, Hairong

    2015-02-01

    Ultrasound shear-wave elastography (SWE) has become a valuable tool for diagnosis of breast tumors. The purpose of this study was to quantify the elastic heterogeneity of breast tumors in SWE by using contourlet-based texture features and evaluating their diagnostic performance for classification of benign and malignant breast tumors, with pathologic results as the gold standard. A total of 161 breast tumors in 125 women who underwent B-mode and SWE ultrasonography before biopsy were included. Five quantitative texture features in SWE images were extracted from the directional subbands after the contourlet transform, including the mean (Tmean), maximum (Tmax), median (Tmed), third quartile (Tqt), and standard deviation (Tsd) of the subbands. Diagnostic performance of the texture features and the classic features was compared using the area under the receiver operating characteristic curve (AUC) and the leave-one-out cross validation with Fisher classifier. The feature Tmean achieved the highest AUC (0.968) among all features and it yielded a sensitivity of 89.1%, a specificity of 94.3% and an accuracy of 92.5% for differentiation between benign and malignant tumors via the leave-one-out cross validation. Compared with the best classic feature, i.e., the maximum elasticity, Tmean improved the AUC, sensitivity, specificity and accuracy by 3.5%, 12.7%, 2.8% and 6.2%, respectively. The Tmed, Tqt and Tsd were also superior to the classic features in terms of the AUC and accuracy. The results demonstrated that the contourlet-based texture features captured the tumor's elastic heterogeneity and improved diagnostic performance contrasted with the classic features. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  18. Familial Clustering of Venous Thromboembolism

    DEFF Research Database (Denmark)

    Sindet-Pedersen, Caroline; Oestergaard, Louise Bruun; Gundlund, Anna

    2016-01-01

    BACKGROUND: Identification of risk factors for venous thromboembolism (VTE) is of utmost importance to improve current prophylactic regimes and treatment guidelines. The extent to which a family history contributes to the risk of VTE needs further exploration. OBJECTIVES: To examine the relative...... rate of VTE in first-degree relatives compared with the general population. METHODS: By crosslinking Danish nationwide registries we identified patients with VTE between 1978 and 2012, and their familial relations. The first member in a family to acquire VTE was defined as the proband. All first...... regression models, with the general population as a fixed reference. RESULTS: We identified 70,767 children of maternal probands, 66,065 children of paternal probands, and 29,183 siblings to sibling probands. Having a maternal proband or a paternal proband were associated with a significantly increased VTE...

  19. Platelet recruitment to venous stent thrombi.

    Science.gov (United States)

    McBane, Robert D; Karnicki, Krzysztof; Wysokinski, Waldemar E

    2013-11-01

    Thrombosis following venous stent placement is a morbid clinical outcome. Whether to target platelets or coagulation factors for venous stent thromboprophylaxis remains unclear. We sought to determine whether integrin α(IIb)β3 antagonism with lamifiban would inhibit platelet recruitment to venous stent thrombosis. Anti-thrombotic efficacy was compared between venous and arterial circulations. Pigs received either lamifiban (0.2 mg/kg bolus plus 0.2 mg/kg/h infusion; n = 6) or saline (n = 12). Carotid arteries were crush injured and then harvested 30 min later to provide an assessment of antithrombotic efficacy in the arterial circulation. Iliac venous stents were then deployed and thrombi allowed to propagate for 2 h before harvesting. Platelet deposition was measured by scintillation detection of autologous (111)In-platelets. Venous thrombi were quantified by weight and compared to platelet, Von Willebrand factor (VWF) and fibrinogen content. Arterial platelet deposition (×10(6)/cm(2)) was reduced >80% by lamifiban (398 ± 437) compared to controls (1,540 ± 883; p thrombi occurs in part through the integrin α(IIb)β3 receptor. Unlike arterial thrombosis, inhibition of this receptor is insufficient to prevent venous stent thrombosis.

  20. Comparison and Combination of Strain and Shear Wave Elastography of Breast Masses for Differentiation of Benign and Malignant Lesions by Quantitative Assessment: Preliminary Study.

    Science.gov (United States)

    Seo, Mirinae; Ahn, Hye Shin; Park, Sung Hee; Lee, Jong Beum; Choi, Byung Ihn; Sohn, Yu-Mee; Shin, So Youn

    2018-01-01

    To compare the diagnostic performance of strain and shear wave elastography of breast masses for quantitative assessment in differentiating benign and malignant lesions and to evaluate the diagnostic accuracy of combined strain and shear wave elastography. Between January and February 2016, 37 women with 45 breast masses underwent both strain and shear wave ultrasound (US) elastographic examinations. The American College of Radiology Breast Imaging Reporting and Data System (BI-RADS) final assessment on B-mode US imaging was assessed. We calculated strain ratios for strain elastography and the mean elasticity value and elasticity ratio of the lesion to fat for shear wave elastography. Diagnostic performances were compared by using the area under the receiver operating characteristic curve (AUC). The 37 women had a mean age of 47.4 years (range, 20-79 years). Of the 45 lesions, 20 were malignant, and 25 were benign. The AUCs for elasticity values on strain and shear wave elastography showed no significant differences (strain ratio, 0.929; mean elasticity, 0.898; and elasticity ratio, 0.868; P > .05). After selectively downgrading BI-RADS category 4a lesions based on strain and shear wave elastographic cutoffs, the AUCs for the combined sets of B-mode US and elastography were improved (B-mode + strain, 0.940; B-mode + shear wave; 0.964; and B-mode, 0.724; P < .001). Combined strain and shear wave elastography showed significantly higher diagnostic accuracy than each individual elastographic modality (P = .031). These preliminary results showed that strain and shear wave elastography had similar diagnostic performance. The addition of strain and shear wave elastography to B-mode US improved diagnostic performance. The combination of strain and shear wave elastography results in a higher diagnostic yield than each individual elastographic modality. © 2017 by the American Institute of Ultrasound in Medicine.

  1. Central venous catheters: the role of radiology

    Energy Technology Data Exchange (ETDEWEB)

    Tan, P.L. [Department of Radiology, John Radcliffe Hospital, Oxford (United Kingdom)]. E-mail: pecklingtan@hotmail.com; Gibson, M. [Department of Radiology, Royal Berkshire Hospital, Reading, Berkshire (United Kingdom)

    2006-01-15

    The insertion and management of long-term venous catheters have long been the province of anaesthetists, intensive care physicians and surgeons. Radiologists are taking an increasing role in the insertion of central venous catheters (CVCs) because of their familiarity with the imaging equipment and their ability to manipulate catheters and guide-wires. The radiological management of the complications of CVCs has also expanded as a result. This article reviews the role of radiology in central venous access, covering the detection and management of their complications.

  2. Quality of life in patients with venous stasis ulcers and others with advanced venous insufficiency.

    Science.gov (United States)

    Tracz, Edyta; Zamojska, Ewa; Modrzejewski, Andrzej; Zaborski, Daniel; Grzesiak, Wilhelm

    2015-01-01

    The quality of life (QoL) in patients with advanced venous insufficiency (including venous stasis ulcers, skin discoloration, stasis eczema, and lipodermatosclerosis) assessed using the Clinical Etiological Anatomical Pathophysiological (CEAP) and Venous Clinical Severity Score (VCSS) classifications is presented. Also, disease features such as: intensity of pain, edema and inflammatory response that exerted the most profound effect on different domains of QoL are reported. The global QoL in patients with lower leg venous ulcerations was relatively similar to that observed in other patients with chronic venous insufficiency. The presence of venous ulcerations was associated with lower QoL in a Physical domain. Significant correlations were found between pain intensity and the values of Physical, Physiological, Level of Independence and Environmental domains, between edema intensity and Social domain as well as between the intensity of inflammatory response and Physical and Spiritual domains.

  3. The Impact of Lower Extremity Venous Ulcers due to Chronic Venous Insufficiency on Quality of Life

    OpenAIRE

    Koupidis, Sotirios A; Paraskevas, Kosmas I.; Stathopoulos, Vassilios; Mikhailidis, Dimitri P.

    2008-01-01

    Lower extremity venous ulcers comprise a complex medical and social issue. The conservative and/or surgical management of venous ulcers is often inadequate. In addition, the psychosocial aspect of the disease is often overlooked and most often undertreated. Common symptoms such as pain, low self-esteem and patient isolation are usually not recognized and therefore not adequately managed. This mini-review summarizes the current data on the management of lower extremity venous ulcers and their ...

  4. Central Venous Line Insertion Revealing Partial Anomalous Pulmonary Venous Return: Diagnosis and Management

    Directory of Open Access Journals (Sweden)

    Bashar Alzghoul

    2017-01-01

    Full Text Available Central venous line malposition is a well-known complication of line insertion. Rarely, it can be mal-positioned in an anomalous pulmonary vein. We present an unusual case of a 56-year-old woman that was found to have partial anomalous pulmonary venous return on central venous line insertion. In this report, we describe a systematic approach to diagnosis and management of this unusual situation.

  5. Central Venous Line Insertion Revealing Partial Anomalous Pulmonary Venous Return: Diagnosis and Management.

    Science.gov (United States)

    Alzghoul, Bashar; Innabi, Ayoub; Chada, Aditya; Tarawneh, Ahmad R; Kakkera, Krishna; Khasawneh, Khaled

    2017-01-01

    Central venous line malposition is a well-known complication of line insertion. Rarely, it can be mal-positioned in an anomalous pulmonary vein. We present an unusual case of a 56-year-old woman that was found to have partial anomalous pulmonary venous return on central venous line insertion. In this report, we describe a systematic approach to diagnosis and management of this unusual situation.

  6. The possibility for use of venous flaps in plastic surgery

    Energy Technology Data Exchange (ETDEWEB)

    Baytinger, V. F., E-mail: baitinger@mail.tomsknet.ru; Kurochkina, O. S., E-mail: kurochkinaos@yandex.ru; Selianinov, K. V.; Baytinger, A. V. [Research Institute of Microsurgery, Tomsk (Russian Federation); Dzyuman, A. N. [Siberian State Medical University, Tomsk (Russian Federation)

    2015-11-17

    The use of venous flaps is controversial. The mechanism of perfusion of venous flaps is still not fully understood. The research was conducted on 56 white rats. In our experimental work we studied two different models of venous flaps: pedicled venous flap (PVF) and pedicled arterialized venous flap (PAVF). Our results showed that postoperative congestion was present in all flaps. However 66.7% of all pedicled venous flaps and 100% of all pedicled arterialized venous flaps eventually survived. Histological examination revealed that postoperatively the blood flow in the skin of the pedicled arterialized venous flap became «re-reversed» again; there were no differences between mechanism of survival of venous flaps and other flaps. On the 7-14th day in the skin of all flaps were processes of neoangiogenesis and proliferation. Hence the best scenario for the clinical use of venous flaps unfolds when both revascularization and skin coverage are required.

  7. The possibility for use of venous flaps in plastic surgery

    Science.gov (United States)

    Baytinger, V. F.; Kurochkina, O. S.; Selianinov, K. V.; Baytinger, A. V.; Dzyuman, A. N.

    2015-11-01

    The use of venous flaps is controversial. The mechanism of perfusion of venous flaps is still not fully understood. The research was conducted on 56 white rats. In our experimental work we studied two different models of venous flaps: pedicled venous flap (PVF) and pedicled arterialized venous flap (PAVF). Our results showed that postoperative congestion was present in all flaps. However 66.7% of all pedicled venous flaps and 100% of all pedicled arterialized venous flaps eventually survived. Histological examination revealed that postoperatively the blood flow in the skin of the pedicled arterialized venous flap became «re-reversed» again; there were no differences between mechanism of survival of venous flaps and other flaps. On the 7-14th day in the skin of all flaps were processes of neoangiogenesis and proliferation. Hence the best scenario for the clinical use of venous flaps unfolds when both revascularization and skin coverage are required.

  8. Transient and 2-Dimensional Shear-Wave Elastography Provide Comparable Assessment of Alcoholic Liver Fibrosis and Cirrhosis

    DEFF Research Database (Denmark)

    Thiele, Maja; Detlefsen, Sönke; Møller, Linda Maria Sevelsted

    2016-01-01

    BACKGROUND & AIMS: Alcohol abuse causes half of all deaths from cirrhosis in the West, but few tools are available for noninvasive diagnosis of alcoholic liver disease. We evaluated 2 elastography techniques for diagnosis of alcoholic fibrosis and cirrhosis; liver biopsy with Ishak score...... and collagen-proportionate area were used as reference. METHODS: We performed a prospective study of 199 consecutive patients with ongoing or prior alcohol abuse, but without known liver disease. One group of patients had a high pretest probability of cirrhosis because they were identified at hospital liver...... clinics (in Southern Denmark). The second, lower-risk group, was recruited from municipal alcohol rehabilitation centers and the Danish national public health portal. All subjects underwent same-day transient elastography (FibroScan), 2-dimensional shear wave elastography (Supersonic Aixplorer), and liver...

  9. Spontaneous thrombosis of developmental venous anomaly (DVA) with venous infarct and acute cerebellar ataxia.

    Science.gov (United States)

    Agarwal, Amit; Kanekar, Sangam; Kalapos, Paul; Vijay, Kanupriya

    2014-08-01

    Developmental venous anomaly (DVA), formally known as venous angioma, is a congenital anatomic variant of the venous drainage of the brain. Although they typically have a benign clinical course and a low symptomatic rate, thrombosis of a drainage vein may occur, leading to potentially debilitating complications. We report a unique case of spontaneous thrombosis of a posterior fossa developmental venous anomaly with cerebellar infarct in a 61-year-old man who presented with acute onset cerebellar ataxia. DVA thrombosis was well-depicted on CT and MR studies. Patient was put on anticoagulant therapy and complete recanalization was seen on follow-up imaging.

  10. Validating the utilisation of venous bicarbonate as a predictor of ...

    African Journals Online (AJOL)

    tubular cast formation, can result in acute kidney injury (AKI). Risk stratification for prognostication in AKI has progressed from various consensus definitions, from the Risk, Injury, Failure, Loss and End-stage renal disease (RIFLE)[1] to the Acute Kidney Injury. Network (AKIN)[2] and now the Kidney Disease Improving Global.

  11. Validating the utilisation of venous bicarbonate as a predictor of ...

    African Journals Online (AJOL)

    The overall mortality rate was 1.9%, 14.8% of patients had AKI, and 3.9% required RRT. Both VB and BE performed well in RRT prediction, with areas under the receiver operating characteristic curve of 0.847 (95% confidence interval (CI) 0.756 - 0.938; p<0.001) and 0.871 (95% CI 0.795 - 0.947; p<0.001), respectively.

  12. Imaging of cerebral venous complications in patients with infections

    Directory of Open Access Journals (Sweden)

    Xudong Shen

    2017-09-01

    Full Text Available Systemic and local infections can cause cerebrovascular complications in the central nervous system. The involvement of cerebral venous system would result in venous or dural venous sinus thrombophlebitis. Images can help evaluate the venous complications in patients with central nervous system infection and provide information in guiding treatment and prognosis. The main focus of this review is to emphasize the proper utilization of imaging modalities in assessment the complications of cerebral venous system in patients with infection.

  13. [Emphysematous gastritis with concomitant portal venous air].

    Science.gov (United States)

    Jeong, Min Yeong; Kim, Jin Il; Kim, Jae Young; Kim, Hyun Ho; Jo, Ik Hyun; Seo, Jae Hyun; Kim, Il Kyu; Cheung, Dae Young

    2015-02-01

    Emphysematous gastritis is a rare form of gastritis caused by infection of the stomach wall by gas forming bacteria. It is a very rare condition that carries a high mortality rate. Portal venous gas shadow represents elevation of intestinal luminal pressure which manifests as emphysematous gastritis or gastric emphysema. Literature reviews show that the mortality rate is especially high when portal venous gas shadow is present on CT scan. Until recently, the treatment of emphysematous gastritis has been immediate surgical intervention. However, there is a recent trend of avoiding surgery because of the frequent occurrence of post-operative complications such as anastomosis leakage. In addition, aggressive surgical treatment has failed to show significant improvement in prognosis. Recently, the authors experienced a case of emphysematous gastritis accompanied by portal venous gas which was treated successfully by conservative treatment without immediate surgical intervention. Herein, we present a case of emphysematous gastritis with concomitant portal venous air along with literature review.

  14. Tuberculosis and Venous Thromboembolism: a case series.

    Science.gov (United States)

    Goncalves, Ivone M; Alves, Daniela Costa; Carvalho, Aurora; do Ceu Brito, Maria; Calvario, Fernando; Duarte, Raquel

    2009-12-16

    Tuberculosis remains an infectious disease with a high prevalence worldwide and represents a major public health issue. Although venous thromboembolism is a rare complication of this disease, it may be a potentially life-threatening event. We report two cases of severe pulmonary tuberculosis associated with venous thromboembolism. A 38 year-old caucasian male that had a thromboembolic event as an unsual presentation form of tuberculosis and a 51 year-old caucasian male that developed deep venous thrombosis later in the course of the disease. An association between inflamation induced by tuberculosis and a hypercoagulable state has been described. Therefore, the occurence of deep venous thrombosis or pulmonary embolic episods, should be considered in patients with tuberculosis particulary during the first weeks of treatment. The physician's awarness of these phenomena is important to an early diagnostic suspicion and prompt treatment in order to prevent fatal outcomes.

  15. [Venous thromboembolic disease: presentation of a case].

    Science.gov (United States)

    Mirpuri-Mirpuri, P G; Álvarez-Cordovés, M M; Pérez-Monje, A

    2013-01-01

    Venous thromboembolic disease in its clinical spectrum includes both deep vein thrombosis and pulmonary thromboembolism, which is usually a complication of deep vein thrombosis. It is a relatively common disease with significant morbidity and requires an accurate diagnosis. They are numerous risk factors for venous thromboembolism, and there is evidence that the risk of thromboembolic disease increases proportionally to the number of predisposing risk factors present. The primary care physician should know the risk factors and suspect the presence of venous thromboembolic disease when there is a compatible clnical picture. The treatment for this pathology is anticoagulation. We report a patient with cardiovascular risk factors who was seen with pain in the right leg and shortness of breath and referred to the hospital with suspected venous thromboembolism, atrial fibrillation and pleural effusion. Copyright © 2012 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España. All rights reserved.

  16. Proof of concept non-invasive estimation of peripheral venous oxygen saturation.

    Science.gov (United States)

    Khan, Musabbir; Pretty, Chris G; Amies, Alexander C; Balmer, Joel; Banna, Houda E; Shaw, Geoffrey M; Geoffrey Chase, J

    2017-05-19

    Pulse oximeters continuously monitor arterial oxygen saturation. Continuous monitoring of venous oxygen saturation (SvO2) would enable real-time assessment of tissue oxygen extraction (O2E) and perfusion changes leading to improved diagnosis of clinical conditions, such as sepsis. This study presents the proof of concept of a novel pulse oximeter method that utilises the compliance difference between arteries and veins to induce artificial respiration-like modulations to the peripheral vasculature. These modulations make the venous blood pulsatile, which are then detected by a pulse oximeter sensor. The resulting photoplethysmograph (PPG) signals from the pulse oximeter are processed and analysed to develop a calibration model to estimate regional venous oxygen saturation (SpvO2), in parallel to arterial oxygen saturation estimation (SpaO2). A clinical study with healthy adult volunteers (n = 8) was conducted to assess peripheral SvO2 using this pulse oximeter method. A range of physiologically realistic SvO2 values were induced using arm lift and vascular occlusion tests. Gold standard, arterial and venous blood gas measurements were used as reference measurements. Modulation ratios related to arterial and venous systems were determined using a frequency domain analysis of the PPG signals. A strong, linear correlation (r 2  = 0.95) was found between estimated venous modulation ratio (RVen) and measured SvO2, providing a calibration curve relating measured RVen to venous oxygen saturation. There is a significant difference in gradient between the SpvO2 estimation model (SpvO2 = 111 - 40.6*R) and the empirical SpaO2 estimation model (SpaO2 = 110 - 25*R), which yields the expected arterial-venous differences. Median venous and arterial oxygen saturation accuracies of paired measurements between pulse oximeter estimated and gold standard measurements were 0.29 and 0.65%, respectively, showing good accuracy of the pulse oximeter system. The main outcome of

  17. Pathophysiology of spontaneous venous gas embolism

    Science.gov (United States)

    Lambertsen, C. J.; Albertine, K. H.; Pisarello, J. B.; Flores, N. D.

    1991-01-01

    The use of controllable degrees and durations of continuous isobaric counterdiffusion venous gas embolism to investigate effects of venous gas embolism upon blood, cardiovascular, and respiratory gas exchange function, as well as pathological effects upon the lung and its microcirculation is discussed. Use of N2O/He counterdiffusion permitted performance of the pathophysiologic and pulmonary microstructural effects at one ATA without hyperbaric or hypobaric exposures.

  18. The soluble urokinase plasminogen activator receptor and its fragments in venous ulcers

    DEFF Research Database (Denmark)

    Ahmad, Anwar; Saha, Prakash; Evans, Colin

    2015-01-01

    functions that include chemotaxis, adhesion, and proliferation, which also have a role in wound healing. The aim of this study was to determine whether suPAR and its cleaved fragments are present in venous ulcers and whether their levels are associated with healing. METHODS: Ulcer exudates were collected...... from patients with venous leg ulcers (n = 30). Healing was defined as complete re-epithelialization within 6 months of compression therapy. Time-resolved fluorescence immunoassays were validated for quantification of suPAR and its fragments in ulcer exudates. The effect of exudates on keratinocyte...... with nonhealers (n = 21). Exudate from healing ulcers stimulated keratinocyte migration (P = .02), whereas depletion of suPAR from exudates resulted in cell apoptosis. CONCLUSIONS: We conclude that suPAR and its fragments are present in the environs of venous ulcers and may act as indicators of the propensity...

  19. Discordance in fibrosis staging between liver biopsy and transient elastography using the FibroScan XL probe.

    Science.gov (United States)

    Myers, Robert P; Pomier-Layrargues, Gilles; Kirsch, Richard; Pollett, Aaron; Beaton, Melanie; Levstik, Mark; Duarte-Rojo, Andres; Wong, David; Crotty, Pam; Elkashab, Magdy

    2012-03-01

    The FibroScan XL probe facilitates liver stiffness measurement (LSM) by transient elastography (TE) in obese patients, yet factors affecting its accuracy have not been described. Our objectives were to examine the prevalence, risk factors, and causes of discordance between fibrosis estimated by the FibroScan XL probe and biopsy. Two hundred and ten patients with chronic liver disease (45% viral hepatitis, 55% nonalcoholic fatty liver disease (NAFLD) and a body mass index (BMI) ≥ 28 kg/m(2)) underwent liver biopsy and TE with the FibroScan XL probe. Predictors of discordance ≥ 2 fibrosis stages between measures, which occurred in 11% of patients (n=24), were identified by comparing patient, TE, and biopsy characteristics of discordant and non-discordant cases. Fibrosis estimated by the FibroScan XL probe was greater than biopsy in 75% (18/24) of discordant cases. Although biopsy quality was not associated with discordance, discordant cases were less likely to have ≥ 10 valid shots (75% vs. 97%; p=0.001), a success rate ≥ 60% (67% vs. 95%; p liver stiffness (IQR/M) liver stiffness was of borderline significance (OR 1.73 per log(10)-transformed value; 95% CI 0.95-3.18; p=0.08). Discordance was 4- to 5-fold more frequent among patients with severe obesity (BMI ≥ 40 kg/m(2): 32% vs. 8%) and liver stiffness above the median of 7.0 kPa (20% vs. 4%; both p liver fibrosis estimated by biopsy and TE using the FibroScan XL probe was infrequent in this obese population. Patients with severe obesity and elevated liver stiffness have the greatest risk of discordance. Copyright © 2011 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

  20. Diagnostic performance of quantitative shear wave elastography in the evaluation of solid breast masses: determination of the most discriminatory parameter.

    Science.gov (United States)

    Au, Frederick Wing-Fai; Ghai, Sandeep; Moshonov, Hadas; Kahn, Harriette; Brennan, Cressida; Dua, Hemi; Crystal, Pavel

    2014-09-01

    The purpose of this article is to assess the diagnostic performance of quantitative shear wave elastography in the evaluation of solid breast masses and to determine the most discriminatory parameter. B-mode ultrasound and shear wave elastography were performed before core biopsy of 123 masses in 112 women. The diagnostic performance of ultrasound and quantitative shear wave elastography parameters (mean elasticity, maximum elasticity, and elasticity ratio) were compared. The added effect of shear wave elastography on the performance of ultrasound was determined. The mean elasticity, maximum elasticity, and elasticity ratio were 24.8 kPa, 30.3 kPa, and 1.90, respectively, for 79 benign masses and 130.7 kPa, 154.9 kPa, and 11.52, respectively, for 44 malignant masses (p elasticity ratio (0.943) was the highest. By adding shear wave elastography parameters to the evaluation of BI-RADS category 4a masses, about 90% of masses could be downgraded to BI-RADS category 3. The numbers of downgraded masses were 40 of 44 (91%) for mean elasticity, 39 of 44 (89%) for maximum elasticity, and 42 of 44 (95%) for elasticity ratio. The numbers of correctly downgraded masses were 39 of 40 (98%) for mean elasticity, 38 of 39 (97%) for maximum elasticity, and 41 of 42 (98%) for elasticity ratio. There was improvement in the diagnostic performance of ultrasound of mass assessment with shear wave elastography parameters added to BI-RADS category 4a masses compared with ultrasound alone. Combined ultrasound and elasticity ratio had the highest improvement, from 35.44% to 87.34% for specificity, from 45.74% to 80.77% for positive predictive value, and from 57.72% to 90.24% for accuracy (p elasticity ratio (0.914) was the highest compared with the other combined parameters. There was a statistically significant difference in the values of the quantitative shear wave elastography parameters of benign and malignant solid breast masses. By adding shear wave elastography parameters to BI

  1. Sigmoid sinus cortical plate dehiscence induces pulsatile tinnitus through amplifying sigmoid sinus venous sound.

    Science.gov (United States)

    Tian, Shan; Wang, Lizhen; Yang, Jiemeng; Mao, Rui; Liu, Zhaohui; Fan, Yubo

    2017-02-08

    Sigmoid sinus cortical plate dehiscence (SSCPD) is common in pulsatile tinnitus (PT) patients, and is treated through SSCPD resurfacing surgery in clinic, but the bio-mechanism is not clear as so far. This study aimed to clarify the bio-mechanism of PT sensation induced by SSCPD, and quantify the relationship of cortical plate (CP) thickness and PT sensation intensity. It was hypothesized that SSCPD would induce PT through significantly amplifying sigmoid sinus (SS) venous sound in this study. Finite element (FE) analysis based on radiology data of typical patient was used to verify this hypothesis, and was validated with clinical reports. In cases with different CP thickness, FE simulations of SS venous sound generation and propagation procedure were performed, involving SS venous flow field, vibration response of tissue overlying dehiscence area (including SS vessel wall and CP) and sound propagation in temporal bone air cells. It was shown in results that SS venous sound at tympanic membrane was 56.9dB in SSCPD case and -45.2dB in intact CP case, and was inaudible in all thin CP cases. It was concluded that SSCPD would directly induce PT through significantly amplifying SS venous sound, and thin CP would not be the only pathophysiology of PT. This conclusion would provide a theoretical basis for the design of SSCPD resurfacing surgery for PT patients with SSCPD or thin CP. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. The International Consolidated Venous Ulcer Guideline Update 2015: Process Improvement, Evidence Analysis, and Future Goals.

    Science.gov (United States)

    Couch, Kara S; Corbett, Lisa; Gould, Lisa; Girolami, Susan; Bolton, Laura

    2017-05-01

    In 2015, members of the Association for the Advancement of Wound Care (AAWC), Wound Healing Society, and the Canadian Association for Enterostomal Therapy formed the International Consolidated Guidelines Taskforce to update the AAWC Venous Ulcer Guidelines to the collaborative, intersociety, endorsed International Consolidated Venous Ulcer Guideline. This "guideline of guidelines" integrates recommendations from all relevant, published evidence-based guidelines on venous ulcer care and prevention. The update process was conducted in accordance with the National Guideline Clearinghouse inclusion criteria and was informed by a systematic review of the evidence, with additional content validation of each venous ulcer management recommendation. Twenty-three (23) wound experts participated. Compared to the 2010 version of the guideline, A-level recommendations increased from 62% to 77%, 31 recommendations were removed, and new recommendations included quality of life evaluations and surgical treatment options. Gaps in the evidence and needed areas for research include surgical, topical, and pharmaceutical interventions. Collaboration among societies and stakeholders and rigorous guideline development processes may expedite the implementation of evidence-based practices, fill in research gaps, and provide a powerful unified voice to regulatory and reimbursement agencies with the ultimate goal of improving outcomes for persons with a venous ulcer.

  3. Venous catheterization with ultrasound navigation

    Science.gov (United States)

    Kasatkin, A. A.; Urakov, A. L.; Nigmatullina, A. R.

    2015-11-01

    By ultrasound scanning it was determined that respiratory movements made by chest of healthy and sick person are accompanied by respiratory chest rise of internal jugular veins. During the exhalation of an individual diameter of his veins increases and during the breath it decreases down to the complete disappearing if their lumen. Change of the diameter of internal jugular veins in different phases can influence significantly the results of vein puncture and cauterization in patients. The purpose of this research is development of the method increasing the efficiency and safety of cannulation of internal jugular veins by the ultrasound visualization. We suggested the method of catheterization of internal jugular veins by the ultrasound navigation during the execution of which the puncture of venous wall by puncture needle and the following conduction of J-guide is carried out at the moment of patient's exhalation. This method decreases the risk of complications development during catheterization of internal jugular vein due to exclusion of perforating wound of vein and subjacent tissues and anatomical structures.

  4. Venous catheterization with ultrasound navigation

    Energy Technology Data Exchange (ETDEWEB)

    Kasatkin, A. A., E-mail: ant-kasatkin@yandex.ru; Nigmatullina, A. R. [Izhevsk State Medical Academy, Kommunarov street, 281, Izhevsk, Russia, 426034 (Russian Federation); Urakov, A. L., E-mail: ant-kasatkin@yandex.ru [Institute of Mechanics Ural Branch of Russian Academy of Sciences, T.Baramzinoy street 34, Izhevsk, Russia, 426067, Izhevsk (Russian Federation); Izhevsk State Medical Academy, Kommunarov street, 281, Izhevsk, Russia, 426034 (Russian Federation)

    2015-11-17

    By ultrasound scanning it was determined that respiratory movements made by chest of healthy and sick person are accompanied by respiratory chest rise of internal jugular veins. During the exhalation of an individual diameter of his veins increases and during the breath it decreases down to the complete disappearing if their lumen. Change of the diameter of internal jugular veins in different phases can influence significantly the results of vein puncture and cauterization in patients. The purpose of this research is development of the method increasing the efficiency and safety of cannulation of internal jugular veins by the ultrasound visualization. We suggested the method of catheterization of internal jugular veins by the ultrasound navigation during the execution of which the puncture of venous wall by puncture needle and the following conduction of J-guide is carried out at the moment of patient’s exhalation. This method decreases the risk of complications development during catheterization of internal jugular vein due to exclusion of perforating wound of vein and subjacent tissues and anatomical structures.

  5. Can we evaluate the levator ani after Kegel exercise in women with pelvic organ prolapse by transperineal elastography? A preliminary study.

    Science.gov (United States)

    Xie, Meng; Zhang, Xuyin; Zhang, Xiaodan; Wang, Wenping; Hua, Keqin

    2018-01-18

    The aim of this study was to evaluate the stiffness variation of the levator ani in patients with stage I/II pelvic organ prolapse (POP) before and after Kegel exercises by transperineal elastography. A total of 20 patients who were diagnosed with staged I/II POP underwent conventional transperineal ultrasound and elastography. For each patient, the levator ani was located and evaluated in the state of Valsalva. After Kegel exercises for 12 weeks, transperineal ultrasound and elastography were repeated. The elasticity images were assessed using a four-point scale scoring system. Of the 20 cases, four had an elastography score of 1, 14 had a score of 2, two had a score of 3, and no cases had a score of 4 in the levator ani before Kegel exercises. After Kegel exercises, one had an elastography score of 1, two had a score of 2, 15 had a score of 3, and two cases had a score of 4. The mean elastography score was statistically significantly higher for the levator ani after Kegel exercises (2.90 ± 0.48) than for the baseline score (1.90 ± 0.29) (p = 0.025). Transperineal elastography was an effective and useful tool in the evaluation of the levator ani in patients with POP-Q stage I/II before and after Kegel exercises.

  6. Reproducibility of real-time shear wave elastography in the evaluation of liver elasticity

    Energy Technology Data Exchange (ETDEWEB)

    Ferraioli, Giovanna, E-mail: giovanna.ferraioli@unipv.it [Ultrasound Unit, Infectious Diseases Department, IRCCS San Matteo Hospital Foundation, University of Pavia, Via Taramelli 5, 27100 Pavia (Italy); Tinelli, Carmine, E-mail: ctinelli@smatteo.pv.it [Clinical Epidemiology and Biometric Unit, IRCCS San Matteo Hospital Foundation, Viale Golgi 19, 27100 Pavia (Italy); Zicchetti, Mabel, E-mail: mabel.zicchetti@unipv.it [Ultrasound Unit, Infectious Diseases Department, IRCCS San Matteo Hospital Foundation, University of Pavia, Via Taramelli 5, 27100 Pavia (Italy); Above, Elisabetta, E-mail: betta.above@gmail.com [Ultrasound Unit, Infectious Diseases Department, IRCCS San Matteo Hospital Foundation, University of Pavia, Via Taramelli 5, 27100 Pavia (Italy); Poma, Gianluigi, E-mail: gigi.poma@libero.it [Ultrasound Unit, Infectious Diseases Department, IRCCS San Matteo Hospital Foundation, University of Pavia, Via Taramelli 5, 27100 Pavia (Italy); Di Gregorio, Marta, E-mail: martadigregorio@virgilio.it [Ultrasound Unit, Infectious Diseases Department, IRCCS San Matteo Hospital Foundation, University of Pavia, Via Taramelli 5, 27100 Pavia (Italy); Filice, Carlo, E-mail: carfil@unipv.it [Ultrasound Unit, Infectious Diseases Department, IRCCS San Matteo Hospital Foundation, University of Pavia, Via Taramelli 5, 27100 Pavia (Italy)

    2012-11-15

    Objective: To evaluate the reproducibility of real-time shear wave elastography in assessing liver elasticity in healthy volunteers. Methods: Forty-two volunteers were studied in day 1. Shear wave elastography studies were performed by using the ultrasound system Aixplorer Trade-Mark-Sign (SuperSonic Imagine S.A., Aix-en-Provence, France) with a convex broadband probe. Measurements were carried by two operators, an expert (operator 1) and a novice (operator 2). Examinations were performed on the right lobe of the liver. Each operator performed 10 consecutive measurements in each volunteer. In a subset of volunteers (n = 18) measurements were performed twice on two different days (day 1 and day 2). Intraobserver and interobserver agreement were assessed by intraclass correlation coefficient. Results: Intraobserver agreement between measurements performed in the same subject in the same day (day 1 or day 2) showed intraclass correlation coefficient values of 0.95 (95% confidence interval, 0.93-0.98) and 0.93 (95% confidence interval, 0.90-0.96) for operator 1 and operator 2, respectively. Intraobserver agreement between measurements performed in the same subject in different days showed intraclass correlation coefficient values of 0.84 (95% confidence interval, 0.69-0.98) and 0.65 (95% confidence interval, 0.39-0.91) for operator 1 and operator 2, respectively. Interobserver agreement was 0.88 (95% confidence interval, 0.82-0.94). Conclusions: The results of this study show that shear wave elastography is a reliable and reproducible noninvasive method for the assessment of liver elasticity. Expert operator had higher reproducibility of measurements over time than novice operator.

  7. 3D Quasi-Static Ultrasound Elastography With Plane Wave In Vivo.

    Science.gov (United States)

    Papadacci, Clement; Bunting, Ethan A; Konofagou, Elisa E

    2017-02-01

    In biological tissue, an increase in elasticity is often a marker of abnormalities. Techniques such as quasi-static ultrasound elastography have been developed to assess the strain distribution in soft tissues in two dimensions using a quasi-static compression. However, as abnormalities can exhibit very heterogeneous shapes, a three dimensional approach would be necessary to accurately measure their volume and remove operator dependency. Acquisition of volumes at high rates is also critical to performing real-time imaging with a simple freehand compression. In this study, we developed for the first time a 3D quasi-static ultrasound elastography method with plane waves that estimates axial strain distribution in vivo in entire volumes at high volume rate. Acquisitions were performed with a 2D matrix array probe of 2.5 MHz frequency and 256 elements. Plane waves were emitted at a volume rate of 100 volumes/s during a continuous motorized and freehand compression. 3D B-mode volumes and 3D cumulative axial strain volumes were successfully estimated in inclusion phantoms and in ex vivo canine liver before and after a high intensity focused ultrasound ablation. We also demonstrated the in vivo feasibility of the method using freehand compression on the calf muscle of a human volunteer and were able to retrieve 3D axial strain volume at a high volume rate depicting the differences in stiffness of the two muscles which compose the calf muscle. 3D ultrasound quasi-static elastography with plane waves could become an important technique for the imaging of the elasticity in human bodies in three dimensions using simple freehand scanning.

  8. Time-Harmonic Ultrasound elastography of the Descending Abdominal Aorta: Initial Results.

    Science.gov (United States)

    Schaafs, Lars-Arne; Tzschätzsch, Heiko; van der Giet, Markus; Reshetnik, Alexander; Steffen, Ingo G; Hamm, Bernd; Braun, Jürgen; Sack, Ingolf; Elgeti, Thomas

    2017-11-01

    Stiffening of central large vessels is considered a key pathophysiologic factor within the cardiovascular system. Current diagnostic parameters such as pulse wave velocity (PWV) indirectly measure aortic stiffness, a hallmark of coronary diseases. The aim of the present study was to perform elastography of the proximal abdominal aorta based on externally induced time-harmonic shear waves. Experiments were performed in 30 healthy volunteers (25 young, 5 old, >50 y) and 5 patients with longstanding hypertension (PWV >10 m/s). B-Mode-guided sonographic time-harmonic elastography was used for measurement of externally induced shear waves at 30-Hz vibration frequency. Thirty-hertz shear wave amplitudes (SWAs) within the abdominal aorta were measured and displayed in real time and processed offline for differences in SWA between systole and diastole (ΔSWA). Data were analyzed using the Kruskal-Wallis test and receiver operating characteristic curve analysis. The change in SWA over the cardiac cycle was reduced significantly in all patients as assessed with ΔSWA (volunteers: mean = 10 ± 5 μm, patients: mean = 4 ± 1 μm; p harmonic elastography of the abdominal aorta is feasible and shows promise for the exploitation of time-varying shear wave amplitudes as a diagnostic marker for aortic wall stiffening. Patients with elevated PWVs suggesting increased aortic wall stiffness were best identified by ΔSWA-a parameter that could be related to the ability of the vessel walls to distend on passages of the pulse wave. Copyright © 2017 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  9. Acoustic radiation force impulse shear wave elastography (ARFI) of acute and chronic pancreatitis and pancreatic tumor.

    Science.gov (United States)

    Goertz, Ruediger S; Schuderer, Johanna; Strobel, Deike; Pfeifer, Lukas; Neurath, Markus F; Wildner, Dane

    2016-12-01

    Acoustic Radiation Force Impulse (ARFI) elastography evaluates tissue stiffness non-invasively and has rarely been applied to pancreas examinations so far. In a prospective and retrospective analysis, ARFI shear wave velocities of healthy parenchyma, pancreatic lipomatosis, acute and chronic pancreatitis, adenocarcinoma and neuroendocrine tumor (NET) of the pancreas were evaluated and compared. In 95 patients ARFI elastography of the pancreatic head, and also of the tail for a specific group, was analysed retrospectively. Additionally, prospectively in 100 patients ARFI was performed in the head and tail of the pancreas. A total of 195 patients were included in the study. Healthy parenchyma (n=21) and lipomatosis (n=30) showed similar shear wave velocities of about 1.3m/s. Acute pancreatitis (n=35), chronic pancreatitis (n=53) and adenocarcinoma (n=52) showed consecutively increasing ARFI values, respectively. NET (n=4) revealed the highest shear wave velocities amounting to 3.62m/s. ARFI elastography showed relevant differences between acute pancreatitis and chronic pancreatitis or adenocarcinoma. With a cut-off value of 1.74m/s for the diagnosis of a malignant disease the sensitivity was 91.1% whereas the specificity amounted to 60.4%. ARFI shear wave velocities present differences in various pathologies of the pancreas. Acute and chronic pancreatitis as well as neoplastic lesions show high ARFI values. Very high elasticity values may indicate malignant disease of the pancreas. However, there is a considerable overlap between the entities. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  10. Added value of Virtual Touch IQ shear wave elastography in the ultrasound assessment of breast lesions

    Energy Technology Data Exchange (ETDEWEB)

    Ianculescu, Victor; Ciolovan, Laura Maria [Radiology Department, Gustave Roussy, Villejuif (France); Dunant, Ariane [Department of Statistics, Gustave Roussy, Villejuif (France); Vielh, Philippe [Department of Biopathology, Gustave Roussy, Villejuif (France); Mazouni, Chafika [Department of Surgery, Gustave Roussy, Villejuif (France); Delaloge, Suzette [Department of Oncology, Gustave Roussy, Villejuif (France); Dromain, Clarisse [Radiology Department, Gustave Roussy, Villejuif (France); Blidaru, Alexandru [Department of Surgery, Bucharest Institute of Oncology, Bucharest (Romania); Balleyguier, Corinne, E-mail: corinne.balleyguier@gustaveroussy.fr [Radiology Department, Gustave Roussy, Villejuif (France); UMR 8081, IR4M, Paris-Sud University, 91405 Orsay (France)

    2014-05-15

    Purpose: To determine the diagnostic performance of Acoustic Radiation Force Impulse (ARFI) Virtual Touch IQ shear wave elastography in the discrimination of benign and malignant breast lesions. Materials and methods: Conventional B-mode and elasticity imaging were used to evaluate 110 breast lesions. Elastographic assessment of breast tissue abnormalities was done using a shear wave based technique, Virtual Touch IQ (VTIQ), implemented on a Siemens Acuson S3000 ultrasound machine. Tissue mechanical properties were interpreted as two-dimensional qualitative and quantitative colour maps displaying relative shear wave velocity. Wave speed measurements in m/s were possible at operator defined regions of interest. The pathologic diagnosis was established on samples obtained by ultrasound guided core biopsy or fine needle aspiration. Results: BIRADS based B-mode evaluation of the 48 benign and 62 malignant lesions achieved 92% sensitivity and 62.5% specificity. Subsequently performed VTIQ elastography relying on visual interpretation of the colour overlay displaying relative shear wave velocities managed similar standalone diagnostic performance with 92% sensitivity and 64.6% specificity. Lesion and surrounding tissue shear wave speed values were calculated and a significant difference was found between the benign and malignant populations (Mann–Whitney U test, p < 0.0001). By selecting a lesion cut-off value of 3.31 m/s we achieved 80.4% sensitivity and 73% specificity. Applying this threshold only to BIRADS 4a masses, we reached overall levels of 92% sensitivity and 72.9% specificity. Conclusion: VTIQ qualitative and quantitative elastography has the potential to further characterise B-mode detected breast lesions, increasing specificity and reducing the number of unnecessary biopsies.

  11. No agreement of mixed venous and central venous saturation in sepsis, independent of sepsis origin

    NARCIS (Netherlands)

    van Beest, Paul A.; van Ingen, Jan; Boerma, E. Christiaan; Holman, Nicole D.; Groen, Henk; Koopmans, Matty; Spronk, Peter E.; Kuiper, Michael A.

    2010-01-01

    Controversy remains regarding the relationship between central venous saturation (ScvO(2)) and mixed venous saturation (SvO(2)) and their use and interchangeability in patients with sepsis or septic shock. We tested the hypothesis that ScvO(2) does not reliably predict SvO(2) in sepsis. Additionally

  12. Femoral venous oxygen saturation is no surrogate for central venous oxygen saturation

    NARCIS (Netherlands)

    van Beest, Paul A.; van der Schors, Alice; Liefers, Henriette; Coenen, Ludo G. J.; Braam, Richard L.; Habib, Najib; Braber, Annemarije; Scheeren, Thomas W. L.; Kuiper, Michael A.; Spronk, Peter E.

    2012-01-01

    Objective:  The purpose of our study was to determine if central venous oxygen saturation and femoral venous oxygen saturation can be used interchangeably during surgery and in critically ill patients. Design:  Prospective observational controlled study. Setting:  Nonacademic university-affiliated

  13. EFSUMB Guidelines and Recommendations on the Clinical Use of Liver Ultrasound Elastography, Update 2017 (Short Version)

    DEFF Research Database (Denmark)

    Dietrich, Christoph F; Bamber, Jeffrey; Berzigotti, Annalisa

    2017-01-01

    We present here the first update of the 2013 EFSUMB (European Federation of Societies for Ultrasound in Medicine and Biology) Guidelines and Recommendations on the clinical use of elastography with a focus on the assessment of diffuse liver disease. The short version provides clinical information...... and in several clinical scenarios is also discussed. All of the recommendations are judged with regard to their evidence-based strength according to the Oxford Centre for Evidence-Based Medicine Levels of Evidence. This updated document is intended to act as a reference and to provide a practical guide for both...

  14. Shear-wave elastography in breast ultrasonography: the state of the art

    Directory of Open Access Journals (Sweden)

    Ji Hyun Youk

    2017-10-01

    Full Text Available Shear-wave elastography (SWE is a recently developed ultrasound technique that can visualize and measure tissue elasticity. In breast ultrasonography, SWE has been shown to be useful for differentiating benign breast lesions from malignant breast lesions, and it has been suggested that SWE enhances the diagnostic performance of ultrasonography, potentially improving the specificity of conventional ultrasonography using the Breast Imaging Reporting and Data System criteria. More recently, not only has SWE been proven useful for the diagnosis of breast cancer, but has also been shown to provide valuable information that can be used as a preoperative predictor of the prognosis or response to chemotherapy.

  15. Shear-wave elastography in breast ultrasonography: the state of the art

    Energy Technology Data Exchange (ETDEWEB)

    Youk, Ji Hyun; Gweon, Hye Mi; Son, Eun Ju [Dept. of Radiology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2017-10-15

    Shear-wave elastography (SWE) is a recently developed ultrasound technique that can visualize and measure tissue elasticity. In breast ultrasonography, SWE has been shown to be useful for differentiating benign breast lesions from malignant breast lesions, and it has been suggested that SWE enhances the diagnostic performance of ultrasonography, potentially improving the specificity of conventional ultrasonography using the Breast Imaging Reporting and Data System criteria. More recently, not only has SWE been proven useful for the diagnosis of breast cancer, but has also been shown to provide valuable information that can be used as a preoperative predictor of the prognosis or response to chemotherapy.

  16. Ultrasound elastography of the liver, spleen, and kidneys in clinically normal cats.

    Science.gov (United States)

    White, Jennifer; Gay, John; Farnsworth, Raelynn; Mickas, Matt; Kim, KwangGi; Mattoon, John

    2014-01-01

    A large amount of overlap exists in the B-mode ultrasound appearance of normal and abnormal liver, spleen, and kidney tissues in cats. Therefore, invasive tissue sampling procedures remain the standard method for diagnosing diseases in these organs. The purpose of our study was to assess the feasibility of ultrasound elastography as a technique for improving noninvasive characterization of the feline liver, spleen, and kidneys. Elastography was performed on 10 unsedated, clinically healthy cats. Numeric (strain) values (0 = softest to 255 = firmest) assigned to color pixels within regions of interest resulted in median scores (interquartile ranges) of body wall, 207.50 (189.75-224.00); liver, 119.00 (105.00-138.25); spleen, 127.50 (121-00-142.00); right renal cortex, 83.50 (64.00-130.00); right renal near field, 125.50 (110.75-139.75); left renal cortex, 77.50 (52.00-116.25); and left renal near field, 126.00 (114.00-145.25). Strain values were not different between organs. Body wall median was the only significantly different value (P < 0.05). Strain ratio values of body wall:organ were as follows: liver, 1.76 (1.38-2.00); spleen, 1.68 (1.47-1.83); right renal cortex, 2.31 (1.61-3.15); right renal near field, 1.62 (1.41-2.01); left renal cortex, 2.66 (1.45-4.13); and left renal near field, 1.51 (1.29-1.89). Subjectively, hepatic and splenic parenchymal tissues were homogeneous in compressibility and similar in elasticity to one another. Renal cortical tissue was softer compared to medullary tissue. Findings indicated that ultrasound elastography is a feasible technique for objectively and subjectively characterizing the feline liver, spleen, and kidneys. Further research is needed in cats with confirmed diseases of these organs, to compare the diagnostic sensitivity of ultrasound elastography vs. B-mode ultrasonography. © 2013 American College of Veterinary Radiology.

  17. Dynamic measurement of local displacements within curing resin-based dental composite using optical coherence elastography

    Science.gov (United States)

    Tomlins, Peter H.; Rahman, Mohammed Wahidur; Donnan, Robert S.

    2016-04-01

    This study aimed to determine the feasibility of using optical coherence elastography to measure internal displacements during the curing phase of a light-activated, resin-based composite material. Displacement vectors were spatially mapped over time within a commercial dental composite. Measurements revealed that the orientation of cure-induced displacement vectors varied spatially in a complex manner; however, each vector showed a systematic evolution with time. Precision of individual displacements was estimated to be ˜1 to 2 μm, enabling submicrometer time-varying displacements to be detected.

  18. Lung transthoracic ultrasound elastography imaging and guided biopsies of subpleural cancer: a preliminary report.

    Science.gov (United States)

    Sperandeo, Marco; Trovato, Francesca M; Dimitri, Lucia; Catalano, Daniela; Simeone, Anna; Martines, Giuseppe Fabio; Piscitelli, Angela Pamela; Trovato, Guglielmo M

    2015-07-01

    Despite the usefulness of elastography in assessing the stiffness/elasticity of tissues, and its proven diagnostic accuracy in thyroid, breast, and prostate cancers, among others, it is not yet applied in transthoracic ultrasound (TUS) scans to investigate lung nodules. To investigate the potential clinical utility of TUS elastography in diagnosing lung cancer proven by fine-needle aspiration biopsy (FNAB). TUS elastography was performed in 95 consecutive patients (71 men, 24 women; age, 62.84 ± 7.37 years) with lesions suspected of involving the chest wall or the pleura detected on chest X-ray or computed tomography (CT). Patients with pleural effusions were not enrolled, but were further evaluated by pleural fluid cytology. Patients were excluded from the study if a diagnosis had already been made based on sputum cytology and/or bronchoscopic histology (making TUS biopsy unnecessary) or if their lung lesions could not be visualized under standard US. Under FNAB, 34 consolidations were ascribed to pneumonia and 65 to cancer. Under TUS, tissue stiffness, detected using a convex multifrequency 2-8-mHz probe and a MyLab™Twice - ElaXto, was scored from 1 (greatest elasticity) to 5 (no elasticity). Subpleural solid masses (2-5 cm) were initially detected by TUS and subsequently assessed by FNAB. Histological diagnoses were: small cell lung cancer (4/61), adenocarcinoma (29/61), squamous cell carcinoma (SCC) (12/61), large cell lung carcinoma (12/61), and lymphomas (4/61). Patients' age and mass sizes (3.06 ± 0.88 cm) were not significantly associated with any histological type. A significant lower elasticity of SCC (4.67 ± 0.492) was observed versus other types of lung cancer (P < 0.005), and versus pneumonia (2.35 ± 0.48). Since only squamous cell lung carcinoma displays the feature of significantly reduced elasticity, and since no clear-cut diagnostic key is yet available, the clinical usefulness of TUS elastography is currently limited

  19. Noninvasive assessment of alcoholic liver disease using unidimensional transient elastography (Fibroscan®)

    Science.gov (United States)

    Lupsor-Platon, Monica; Badea, Radu

    2015-01-01

    Unidimensional transient elastography (TE) is a noninvasive technique, which has been increasingly used in the assessment of diffuse liver diseases. This paper focuses on reviewing the existing data on the use of TE in the diagnosis of fibrosis and in monitoring disease progression in alcoholic liver disease, on the factors that may influence the result of fibrosis prediction, and last but not least, on its potential use in assessing the steatosis degree. Therefore, this field is far from being exhausted and deserves more attention. Further studies are required, on large groups of biopsied patients, in order to find answers to all the remaining questions in this field. PMID:26576080

  20. Elastography in the assessment of sentinel lymph nodes prior to dissection

    Energy Technology Data Exchange (ETDEWEB)

    Tourasse, Christophe, E-mail: christophe.tourasse@radiologie-lyon.com [Radiology Department, Hopital Prive Jean Mermoz, 55 avenue Jean Mermoz, 69008 Lyon (France); Denier, Jean Francois [Anatomopathology Department, Technipath, 41 allee des Cypres, 69760 Limonest (France); Awada, Azzam; Gratadour, Anne-Christel; Nessah-Bousquet, Karima [Gynaecological and Breast Surgery Department, Hopital Prive Jean Mermoz, 69008 Lyon (France); Gay, Joeel [SuperSonic Imagine, Les Jardins de la Duranne - Bat. F, 510, rue Rene Descartes, 13857 Aix-en-Provence Cedex (France)

    2012-11-15

    Objective: Breast cancer starts as a local tumor but can become metastatic and spread via the lymph nodes. When the pre-operative assessment of the axillary lymph nodes is negative patients generally undergo sentinel node biopsy (SNB), followed by a secondary surgical axillary lymph node dissection (ALND) if the SNB is positive. The extemporaneous anatomo-pathological analysis of the sentinel lymph node enables metastases to be detected and an ALND at the same time of the SNB. The goal of this study was to evaluate the added value of ShearWave Elastography (SWE), compared with the conventional pre-operative assessment, in the screening of sentinel lymph nodes with a high metastatic risk, which could then benefit from an extemporaneous anatomo-pathological analysis. Patients and methods: Women undergoing breast surgery with SNB were prospectively enrolled. Before surgery, they underwent ultrasound and elastography imaging of axillary lymph nodes using the SuperSonic Imagine device and its ShearWave Trade-Mark-Sign elastography mode (SWE Trade-Mark-Sign ). The results obtained were compared to the immunohistochemical results for the removed lymph nodes. Results: 65 patients were enrolled. From the 103 lymph nodes examined by elastography and the 185 lymph nodes removed we were able to pair 81; 70 were healthy and 11 were malignant. The stiffness measurements (mean and maximal values) were significantly different between the healthy and metastatic lymph nodes, (p < 0.05). The areas under the ROC curves were 0.76 (95% confidence interval (CI): 0.58-0.94) and 0.75 (95%CI: 0.55-0.95) for the mean and the maximal stiffness, respectively. Conclusion: These encouraging results show a correlation between the metastatic risk of lymph nodes and their increased mean stiffness. Elasticity variables and potential thresholds that seem to predict the metastatic status of axillary lymph nodes were identified. If confirmed by further larger studies, these results could be useful in

  1. [IMPORTANCE OF SHEAR WAVE ELASTOGRAPHY OF LIVERS IN PRACTICALLY HEALTHY PREGNANT WOMEN].

    Science.gov (United States)

    Sariyeva, E; Salahova, S; Bayramov, N

    2017-01-01

    Pulse-wave elastography (SWE) that is one of the mostly used methods in the recent years holds important place in assessment of liver fibrosis. However there is no exact information on the results of liver elastography in healthy pregnant women in the world literature. The aim of the study was to investigate theSWE parameters of liver elastography in practically healthy pregnant women. The subject of the research was 50 practically healthy pregnant women within 18-45 years old (mean age 27.7±0.7). The pregnant women with genital and extragenital diseases were not included to the research. The research work was executed in the II Department of Obstetrics and Gynecology of Azerbaijan Medical University. SWE of liver in pregnant women was conducted in the I Department of Surgical Diseases of Azerbaijan Medical University through Supersonic Aixplorer Multi Wave device presented by the Scientific Development Foundation under the President of the Azerbaijan Republic. The obtained tissue hardness indicators are assessed under METAVIR scale. The results of the research showed that the measures of liver in practically healthy pregnant women are normal, edges flat, its echogenicity mainly normal, echostructure of its parenchyma homogenous, hardness was F0-F1 (normal) under METAVIR scale, fibrosis not observed. The obtained results were processed by variational (power average, percentile distribution) and correlation (ρ-Spearman) analyzes using the statistical package SPSS-20. A statistical study of the distribution of liver density in healthy women showed that the average density was 4,43±0,01 with 95% confidence interval (4,23 - 4,63). The histogram of distribution of liver density in practically healthy women belongs to the family of normal distributions with coefficients of variation coefficient (16.3%), asymmetry (-0.861±0.337) and excess (-0.068±0.662). Correlation analysis in healthy women did not reveal a reliable relationship between age and liver density (ρ=0

  2. Reprint of “Update on ultrasound elastography: Miscellanea. Prostate, testicle, musculo-skeletal”

    Energy Technology Data Exchange (ETDEWEB)

    Correas, J.M. [Descartes University and Necker University Hospital, Department of Adult Radiology, Paris (France); Drakonakis, E. [Nuffield Orthopaedic Centre, Oxford (United Kingdom); Isidori, A.M. [Sapienza University of Rome, Department of Experimental Medicine, Rome (Italy); Hélénon, O. [Descartes University and Necker University Hospital, Department of Adult Radiology, Paris (France); Pozza, C. [Sapienza University of Rome, Department of Experimental Medicine, Rome (Italy); Cantisani, V., E-mail: vito.cantisani@uniroma1.it [Sapienza University of Rome, Department of Radiology, Rome (Italy); Di Leo, N.; Maghella, F.; Rubini, A.; Drudi, F.M.; D’ambrosio, F. [Sapienza University of Rome, Department of Radiology, Rome (Italy)

    2014-03-15

    Nowadays ultrasound elastosonography is an established technique, although with limited clinical application, used to assess tissue stiffness, which is a parameter that in most cases is associated with malignancy. However, although a consistent number of articles have been published about several applications of elastosonography, its use in certain human body districts is still not well defined. In this paper we write on the use of elastosonography in prostate, testicle and musculo-skeletal apparatus. We report and compare the work of several authors, different type of elastosonography (shear wave, strain elastography, etc.) and instrumental data obtained in the study of both benign and malignant lesions.

  3. Shear-wave elastography in breast ultrasonography: the state of the art

    Science.gov (United States)

    2017-01-01

    Shear-wave elastography (SWE) is a recently developed ultrasound technique that can visualize and measure tissue elasticity. In breast ultrasonography, SWE has been shown to be useful for differentiating benign breast lesions from malignant breast lesions, and it has been suggested that SWE enhances the diagnostic performance of ultrasonography, potentially improving the specificity of conventional ultrasonography using the Breast Imaging Reporting and Data System criteria. More recently, not only has SWE been proven useful for the diagnosis of breast cancer, but has also been shown to provide valuable information that can be used as a preoperative predictor of the prognosis or response to chemotherapy. PMID:28513127

  4. Pharmacological adjuncts for chronic venous ulcer healing: a systematic review.

    Science.gov (United States)

    Varatharajan, Lavanya; Thapar, Ankur; Lane, Tristan; Munster, Alex B; Davies, Alun Huw

    2016-06-01

    The aim of this study was to systematically review the current evidence and determine whether there is a clinical benefit for using pharmacological agents as adjunctive treatment for chronic venous ulcers. A systematic review of the MEDLINE and EMBASE (from 1 January 1947 through 15 August 2013) and Cochrane databases (from inception through 15 August 2013) was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Inclusion criteria were all randomised controlled trials investigating pharmacological adjuncts for the treatment of venous ulcers with a minimum sample size of 20 patients for each treatment arm. Ten relevant articles were identified; one pilot randomised controlled trial and four Cochrane reviews were included. Pentoxifylline, aspirin, sulodexide, mesoglycan, flavonoids, thromboxane A2 antagonist (ifetroban), zinc, prostaglandin and prostacyclin analogues were the drugs reviewed. Pentoxifylline was found to be more effective than placebo in terms of complete ulcer healing or in causing a significant improvement (greater than 60% reduction in ulcer size) (RR 1.70, 95% CI 1.30 to 2.24). Aspirin and flavonoids show potential to be effective adjuncts but methodological shortcomings and issues with bias limit the validity of results from trials involving each of these drugs, respectively. There was no significant difference between placebo and Ifetroban and likewise pooled results from trials investigating sulodexide and zinc showed no benefit in comparison to placebo. Many systemic pharmacological agents have been investigated as adjuncts to venous ulcer healing; however, pentoxifylline (400 mg, three times a day) is currently the only drug that has promising evidence to support its use. Other compounds are in early stage research. © The Author(s) 2015.

  5. Thai venous stroke prognostic score: TV-SPSS.

    Science.gov (United States)

    Poungvarin, Niphon; Prayoonwiwat, Naraporn; Ratanakorn, Disya; Towanabut, Somchai; Tantirittisak, Tassanee; Suwanwela, Nijasri; Phanthumchinda, Kamman; Tiamkoa, Somsak; Chankrachang, Siwaporn; Nidhinandana, Samart; Laptikultham, Somsak; Limsoontarakul, Sansern; Udomphanthuruk, Suthipol

    2009-11-01

    Prognosis of cerebral venous sinus thrombosis (CVST) has never been studied in Thailand. A simple prognostic score to predict poor prognosis of CVST has also never been reported. The authors are aiming to establish a simple and reliable prognostic score for this condition. The medical records of CVST patients from eight neurological training centers in Thailand who received between April 1993 and September 2005 were reviewed as part of this retrospective study. Clinical features included headache, seizure, stroke risk factors, Glasgow coma scale (GCS), blood pressure on arrival, papilledema, hemiparesis, meningeal irritation sign, location of occluded venous sinuses, hemorrhagic infarction, cerebrospinal fluid opening pressure, treatment options, length of stay, and other complications were analyzed to determine the outcome using modified Rankin scale (mRS). Poor prognosis (defined as mRS of 3-6) was determined on the discharge date. One hundred ninety four patients' records, 127 females (65.5%) and mean age of 36.6 +/- 14.4 years, were analyzed Fifty-one patients (26.3%) were in the poor outcome group (mRS 3-6). Overall mortality was 8.4%. Univariate analysis and then multivariate analysis using SPSS version 11.5 revealed only four statistically significant predictors influencing outcome of CVST They were underlying malignancy, low GCS, presence of hemorrhagic infarction (for poor outcome), and involvement of lateral sinus (for good outcome). Thai venous stroke prognostic score (TV-SPSS) was derived from these four factors using a multiple logistic model. A simple and pragmatic prognostic score for CVST outcome has been developed with high sensitivity (93%), yet low specificity (33%). The next study should focus on the validation of this score in other prospective populations.

  6. Venous injury in abusive head trauma

    Energy Technology Data Exchange (ETDEWEB)

    Choudhary, Arabinda K. [Nemours A. I. duPont Hospital for Children, Department of Radiology, Wilmington, DE (United States); Bradford, Ray; Thamburaj, K.; Boal, Danielle K.B. [Hershey Medical Center, Department of Radiology, Hershey, PA (United States); Dias, Mark S. [Hershey Medical Center, Department of Neurosurgery, Hershey, PA (United States)

    2015-11-15

    Abusive head trauma (AHT) is an important cause of serious brain injury in infants and young children who have characteristic clinical and imaging findings that are discordant with the clinical history provided. Recent attention has focused on abnormalities of the cranial venous sinuses and cortical veins, both on MRI and at autopsy. Although many have interpreted these to be secondary to the AHT, some have recently argued that these venous abnormalities represent primary cortical sinus and venous thrombosis that leads secondarily to subdural hemorrhage and secondary brain injury. Direct trauma to the veins and sinuses has been reported at autopsy in AHT, but there has been no systematic study of venous abnormalities in cases of AHT. The purpose of this study was to define the incidence and characteristics of venous and sinus abnormalities in AHT. We included all children <36 months of age who were diagnosed with abusive head trauma between 2001 and 2012 and who had MRI and magnetic resonance (MR) venography as part of their diagnostic workup. We analyzed age, gender and clinical findings. MRI and MR venography were analyzed independently by two neuroradiologists with a focus on abnormalities involving the intracranial veins and venous sinuses. A total of 45 children were included. The median age was 3 months (range 15 days to 31 months) and 28 were boys (62%). Clinical findings included retinal hemorrhage in 71% and extracranial fractures in 55%. CT or MRI demonstrated subdural hemorrhage in 41 (91%); none had subdural effusions. In 31 cases (69%) MR venography demonstrated mass effect on the venous sinuses or cortical draining veins, with either displacement or partial or complete effacement of the venous structures from an adjacent subdural hematoma or brain swelling. We also describe the lollipop sign, which represents direct trauma to the cortical bridging veins and was present in 20/45 (44%) children. Evidence of displacement or compression of cortical veins

  7. Usefulness of acoustic radiation force impulse elastography in the differential diagnosis of benign and malignant solid pancreatic lesions

    Directory of Open Access Journals (Sweden)

    Min Kyoung Park

    2014-01-01

    Conclusion:

    ARFI elastography can determine the relative stiffness between a lesion and the background pancreatic parenchyma using VTI and VTQ, which is helpful in the differentiation between benign and malignant solid pancreatic lesions.

  8. Efficacy of an artificial neural network-based approach to endoscopic ultrasound elastography in diagnosis of focal pancreatic masses

    DEFF Research Database (Denmark)

    Mortensen, Michael Bau

    2012-01-01

    Săftoiu A, Vilmann P, Gorunescu F, Janssen J, Hocke M, Larsen M, Iglesias-Garcia J, Arcidiacono P, Will U, Giovannini M, Dietrich CF, Havre R, Gheorghe C, McKay C, Gheonea DI, Ciurea T; European EUS Elastography Multicentric Study Group. Clin Gastroenterol Hepatol. 2012 Jan;10(1):84-90...

  9. Investigation of the acute plantar fasciitis with contrast-enhanced ultrasound and shear wave elastography - first results.

    Science.gov (United States)

    Putz, Franz Josef; Hautmann, Matthias G; Banas, Miriam; Jung, Ernst Michael

    2017-09-04

    The plantar fasciitis is a common disease with a high prevalence in public and a frequent cause of heel pain. In our pilot study, we wanted to characterise the feasibility of shear-wave elastography and contrast-enhanced ultrasound (CEUS) in the assessment of the plantar fasciitis. 23 cases of painful heels were examined by B-Mode ultrasound, Power Doppler (PD), shear wave elastography and contrast-enhanced ultrasound before anti-inflammatory radiation. Time-intensity-curves were analysed by the integrated software. The results for area-under-the-curve (AUC), peak, time-to-peak (TTP) and mean-transit-time (MTT) were compared between the plantar fascia and the surrounding tissue. All cases showed thickening of the plantar fascia, in most cases with interstitial oedema (87.0%). Shear wave elastography showed inhomogeneous stiffness of the plantar fascia. 83.3% of cases showed a visible hyperperfusion in CEUS at the proximal plantar fascia in comparison to the surrounding tissue. This hyperperfusion could also be found in 75.0% of cases with no signs of vascularisation in PD. AUC (p = 0.0005) and peak (p = 0.037) were significantely higher in the plantar fascia than in the surrounding tissue. CEUS and shear wave elastography are new diagnostic tools in the assessment of plantar fasciitis and can provide quantitative parameters for monitoring therapy.

  10. Fractal network dimension and viscoelastic powerlaw behavior: II. An experimental study of structure-mimicking phantoms by magnetic resonance elastography

    Science.gov (United States)

    Guo, Jing; Posnansky, Oleg; Hirsch, Sebastian; Scheel, Michael; Taupitz, Matthias; Braun, Juergen; Sack, Ingolf

    2012-06-01

    The dynamics of the complex shear modulus, G*, of soft biological tissue is governed by the rigidity and topology of multiscale mechanical networks. Multifrequency elastography can measure the frequency dependence of G* in soft biological tissue, providing information about the structure of tissue networks at multiple scales. In this study, the viscoelastic properties of structure-mimicking phantoms containing tangled paper stripes embedded in agarose gel are investigated by multifrequency magnetic resonance elastography within the dynamic range of 40-120 Hz. The effective media viscoelastic properties are analyzed in terms of the storage modulus (the real part of G*), the loss modulus (the imaginary part of G*) and the viscoelastic powerlaw given by the two-parameter springpot model. Furthermore, diffusion tensor imaging is used for investigating the effect of network structures on water mobility. The following observations were made: the random paper networks with fractal dimensions between 2.481 and 2.755 had no or minor effects on the storage modulus, whereas the loss modulus was significantly increased about 2.2 kPa per fractal dimension unit (R = 0.962, P soft-tissue viscoelastic parameters. In the dynamic range of in vivo elastography, the fractal network dimension primarily correlates to the loss behavior of soft tissue as can be seen from the loss modulus or the powerlaw exponent of the springpot model. These findings represent the experimental underpinning of structure-sensitive elastography for an improved characterization of various soft-tissue diseases.

  11. In Vivo Evaluation of the Biomechanical Properties of Optic Nerve and Peripapillary Structures by Ultrasonic Shear Wave Elastography in Glaucoma

    OpenAIRE

    Dikici; Mihmanli; Kilic; Ozkok; Kuyumcu; Sultan,; Samanci; Halit Yilmaz; Rafiee; Tamcelik; Isik Hasiloglu; Kantarci

    2016-01-01

    Background Primary open-angle glaucoma is a multifactorial serious disease characterized by progressive retinal ganglion cell death and loss of visual field. Objectives The purposes of this study were to investigate shear wave elastography (SWE) use in the evaluation of the optic nerve (ON) and peripapillary structures, and to compare the findings between glaucomatous and control eyes. Patients...

  12. Stratifying the Risk of Venous Thromboembolism in Otolaryngology

    Science.gov (United States)

    Shuman, Andrew G.; Hu, Hsou Mei; Pannucci, Christopher J.; Jackson, Christopher R.; Bradford, Carol R.; Bahl, Vinita

    2015-01-01

    Objective The consequences of perioperative venous thromboembolism (VTE) are devastating; identifying patients at risk is an essential step in reducing morbidity and mortality. The utility of perioperative VTE risk assessment in otolaryngology is unknown. This study was designed to risk-stratify a diverse population of otolaryngology patients for VTE events. Study Design Retrospective cohort study. Setting Single-institution academic tertiary care medical center. Subjects and Methods Adult patients presenting for otolaryngologic surgery requiring hospital admission from 2003 to 2010 who did not receive VTE chemoprophylaxis were included. The Caprini risk assessment was retrospectively scored via a validated method of electronic chart abstraction. Primary study variables were Caprini risk scores and the incidence of perioperative venous thromboembolic outcomes. Results A total of 2016 patients were identified. The overall 30-day rate of VTE was 1.3%. The incidence of VTE in patients with a Caprini risk score of 6 or less was 0.5%. For patients with scores of 7 or 8, the incidence was 2.4%. Patients with a Caprini risk score greater than 8 had an 18.3% incidence of VTE and were significantly more likely to develop a VTE when compared to patients with a Caprini risk score less than 8 (P otolaryngology patients for 30-day VTE events and allows otolaryngologists to identify patient subgroups who have a higher risk of VTE in the absence of chemoprophylaxis. PMID:22261490

  13. Diagnosing cysts with correlation coefficient images from 2-dimensional freehand elastography.

    Science.gov (United States)

    Booi, Rebecca C; Carson, Paul L; O'Donnell, Matthew; Richards, Michael S; Rubin, Jonathan M

    2007-09-01

    We compared the diagnostic potential of using correlation coefficient images versus elastograms from 2-dimensional (2D) freehand elastography to characterize breast cysts. In this preliminary study, which was approved by the Institutional Review Board and compliant with the Health Insurance Portability and Accountability Act, we imaged 4 consecutive human subjects (4 cysts, 1 biopsy-verified benign breast parenchyma) with freehand 2D elastography. Data were processed offline with conventional 2D phase-sensitive speckle-tracking algorithms. The correlation coefficient in the cyst and surrounding tissue was calculated, and appearances of the cysts in the correlation coefficient images and elastograms were compared. The correlation coefficient in the cysts was considerably lower (14%-37%) than in the surrounding tissue because of the lack of sufficient speckle in the cysts, as well as the prominence of random noise, reverberations, and clutter, which decorrelated quickly. Thus, the cysts were visible in all correlation coefficient images. In contrast, the elastograms associated with these cysts each had different elastographic patterns. The solid mass in this study did not have the same high decorrelation rate as the cysts, having a correlation coefficient only 2.1% lower than that of surrounding tissue. Correlation coefficient images may produce a more direct, reliable, and consistent method for characterizing cysts than elastograms.

  14. Fetal adrenal gland biometry and cervical elastography as predictors of preterm birth: A comparative study.

    Science.gov (United States)

    Agarwal, Shubhra; Agarwal, Arjit; Joon, Pawan; Saraswat, Shalini; Chandak, Shruti

    2018-02-01

    Preterm birth is a major health problem in developing and developed countries leading to rising health care costs and long-term neurodevelopmental disability. The study aims to evaluate the role of new quantitative markers, like the elastography of cervix (shear wave speed estimation), fetal adrenal zone enlargement, and corrected fetal adrenal gland volume; in preterm birth prediction and analyze their relative importance. Thus, these markers may be beneficial in early preterm birth detection and prevent the related morbidities. Thirty pregnant females (from 28 to 37 weeks of gestational age), showing clinical signs and delivery outcome of preterm birth were included in the study with an equal number of not-in-labor antenatal females at ≥37 weeks as controls. These patients were categorized as preterm and term groups. Both the groups were subjected to trans-abdominal ultrasonography where cervical length, cervical shear wave speed (dynamic elastography) and fetal adrenal gland parameters were measured. Shear wave speed estimation of the antenatal cervix showed the highest sensitivity and specificity (96.7% and 87% respectively) in the prediction of preterm birth and also showed a strong correlation with fetal adrenal gland enlargement. Fetal adrenal zone enlargement was also shown to be a reliable marker of preterm birth, however, with reduced sensitivity and specificity than shear wave speed. The elastographic advancement and fetal adrenal biometry derived quantitative markers can be used as an objective and standard criterion for accurate prediction of preterm birth.

  15. Noninvasive Vascular Elastography With Plane Strain Incompressibility Assumption Using Ultrafast Coherent Compound Plane Wave Imaging.

    Science.gov (United States)

    Porée, Jonathan; Garcia, Damien; Chayer, Boris; Ohayon, Jacques; Cloutier, Guy

    2015-12-01

    Plane strain tensor estimation using non-invasive vascular ultrasound elastography (NIVE) can be difficult to achieve using conventional focus beamforming due to limited lateral resolution and frame rate. Recent developments in compound plane wave (CPW) imaging have led to high speed and high resolution imaging. In this study, we present the performance of NIVE using coherent CPW. We show the impact of CPW beamforming on strain estimates compared to conventional focus sequences. To overcome the inherent variability of lateral strains, associated with the low lateral resolution of linear array transducers, we use the plane strain incompressibility to constrain the estimator. Taking advantage of the approximate tenfold increase in frame rate of CPW compared with conventional focus imaging, we introduce a time-ensemble estimation approach to further improve the elastogram quality. By combining CPW imaging with the constrained Lagrangian speckle model estimator, we observe an increase in elastography quality (∼ 10 dB both in signal-to-noise and contrast-to-noise ratios) over a wide range of applied strains (0.02 to 3.2%).

  16. Transient Elastography for Spleen Stiffness Measurement in Patients With Cirrhosis: Role in Degree of Thrombocytopenia.

    Science.gov (United States)

    Chien, Cheng-Hung; Lin, Yi-Lan; Chien, Rong-Nan; Hu, Ching-Chih; Yen, Cho-Li; Lee, Tsung-Shih; Hsieh, Po-Jen; Lin, Chih-Lang

    2016-09-01

    The purpose of our study was to evaluate the relationship between spleen stiffness measured by transient elastography and the degree of thrombocytopenia in patients with liver cirrhosis. A total of 67 patients with liver cirrhosis were prospectively enrolled in the study. All patients underwent single-day hematologic and biochemical tests, sonography, and transient elastography of the liver and spleen. Thrombocytopenia was categorized as mild (platelet count, 75,000-150,000/μL), moderate (50,000-75,000/μL), and severe (thrombocytopenia was significantly correlated with spleen stiffness (P = .001) and spleen size (P = .002) but not with liver stiffness (P = .086). In patients without splenomegaly, spleen stiffness values were significantly higher in patients with thrombocytopenia than in those without thrombocytopenia (P = .035). In patients with splenomegaly, spleen stiffness values were significantly higher in patients with moderate to severe thrombocytopenia than in those with a normal platelet count or mild thrombocytopenia (P = .007). Compared to liver stiffness, spleen stiffness showed a better and statistically significant correlation with platelet count and spleen size in patients with cirrhosis. The degree of thrombocytopenia was directly correlated with spleen stiffness, irrespective of the presence of splenomegaly. The clinical phenomenon of unexpected thrombocytopenia may be explained by a subtle or irreversible change in spleen stiffness.

  17. Role of Acoustic Radiation Force Impulse (ARFI) Elastography in Determination of Severity of Benign Prostate Hyperplasia.

    Science.gov (United States)

    Alan, Bircan; Utangaç, Mazhar; Göya, Cemil; Dağgülli, Mansur

    2016-11-23

    BACKGROUND The aim of this study was to investigate the potential contribution of acoustic radiation force impulse (ARFI) elastography to the determination of the severity of benign prostate hypertrophy (BPH) by performing shear wave velocity (SWV) measurements of the prostate using ARFI technology. MATERIAL AND METHODS Sixty BPH patients and 40 healthy volunteers were included in this study. SWV measurements of the prostate were performed by transabdominal ultrasonography (US), both in the BPH patients and control subjects. The BPH patients also underwent uroflowmetry measurements. Using the International Prostate Symptom Score (IPSS), the BPH patients were divided into two subgroups, a mild-to-moderate BPH group and a severe BPH group, to compare SWV values. RESULTS The BPH patients had higher SWV values for the central area of the prostate compared to the control subjects (2.52±0.59 m/s and 1.47±0.42 m/s, pprostate were higher in the severe BPH group compared to the mild-to-moderate BPH group (2.62±0.58 and 2.25±0.55, p=0.02). CONCLUSIONS Our ARFI elastography results indicated that the central prostate SWV values of BPH patients were significantly higher relative to those of a healthy control group. The central prostate SWV values increased in proportion to the increased severity of BPH. Measurement of SWV by ARFI technology constitutes a non-invasive alternative to other methods for the determination of BPH severity.

  18. Noncontact Elastic Wave Imaging Optical Coherence Elastography for Evaluating Changes in Corneal Elasticity Due to Crosslinking

    Science.gov (United States)

    Singh, Manmohan; Li, Jiasong; Vantipalli, Srilatha; Wang, Shang; Han, Zhaolong; Nair, Achuth; Aglyamov, Salavat R.; Twa, Michael D.; Larin, Kirill V.

    2016-01-01

    The mechanical properties of tissues can provide valuable information about tissue integrity and health and can assist in detecting and monitoring the progression of diseases such as keratoconus. Optical coherence elastography (OCE) is a rapidly emerging technique, which can assess localized mechanical contrast in tissues with micrometer spatial resolution. In this work we present a noncontact method of optical coherence elastography to evaluate the changes in the mechanical properties of the cornea after UV-induced collagen cross-linking. A focused air-pulse induced a low amplitude (μm scale) elastic wave, which then propagated radially and was imaged in three dimensions by a phase-stabilized swept source optical coherence tomography (PhS-SSOCT) system. The elastic wave velocity was translated to Young’s modulus in agar phantoms of various concentrations. Additionally, the speed of the elastic wave significantly changed in porcine cornea before and after UV-induced corneal collagen cross-linking (CXL). Moreover, different layers of the cornea, such as the anterior stroma, posterior stroma, and inner region, could be discerned from the phase velocities of the elastic wave. Therefore, because of noncontact excitation and imaging, this method may be useful for in vivo detection of ocular diseases such as keratoconus and evaluation of therapeutic interventions such as CXL. PMID:27547022

  19. Reliable protocol for shear wave elastography of lower limb muscles at rest and during passive stretching.

    Science.gov (United States)

    Dubois, Guillaume; Kheireddine, Walid; Vergari, Claudio; Bonneau, Dominique; Thoreux, Patricia; Rouch, Philippe; Tanter, Mickael; Gennisson, Jean-Luc; Skalli, Wafa

    2015-09-01

    Development of shear wave elastography gave access to non-invasive muscle stiffness assessment in vivo. The aim of the present study was to define a measurement protocol to be used in clinical routine for quantifying the shear modulus of lower limb muscles. Four positions were defined to evaluate shear modulus in 10 healthy subjects: parallel to the fibers, in the anterior and posterior aspects of the lower limb, at rest and during passive stretching. Reliability was first evaluated on two muscles by three operators; these measurements were repeated six times. Then, measurement reliability was compared in 11 muscles by two operators; these measurements were repeated three times. Reproducibility of shear modulus was 0.48 kPa and repeatability was 0.41 kPa, with all muscles pooled. Position did not significantly influence reliability. Shear wave elastography appeared to be an appropriate and reliable tool to evaluate the shear modulus of lower limb muscles with the proposed protocol. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  20. Magnetomotive optical coherence elastography for relating lung structure and function in cystic fibrosis

    Science.gov (United States)

    Chhetri, Raghav K.; Carpenter, Jerome; Superfine, Richard; Randell, Scott H.; Oldenburg, Amy L.

    2010-02-01

    Cystic fibrosis (CF) is a genetic defect in the cystic fibrosis transmembrane conductance regulator protein and is the most common life-limiting genetic condition affecting the Caucasian population. It is an autosomal recessive, monogenic inherited disorder characterized by failure of airway host defense against bacterial infection, which results in bronchiectasis, the breakdown of airway wall extracellular matrix (ECM). In this study, we show that the in vitro models consisting of human tracheo-bronchial-epithelial (hBE) cells grown on porous supports with embedded magnetic nanoparticles (MNPs) at an air-liquid interface are suitable for long term, non-invasive assessment of ECM remodeling using magnetomotive optical coherence elastography (MMOCE). The morphology of ex vivo CF and normal lung tissues using OCT and correlative study with histology is also examined. We also demonstrate a quantitative measure of normal and CF airway elasticity using MMOCE. The improved understanding of pathologic changes in CF lung structure and function and the novel method of longitudinal in vitro ECM assessment demonstrated in this study may lead to new in vivo imaging and elastography methods to monitor disease progression and treatment in cystic fibrosis.

  1. High-resolution mechanical imaging of glioblastoma by multifrequency magnetic resonance elastography.

    Directory of Open Access Journals (Sweden)

    Kaspar-Josche Streitberger

    Full Text Available OBJECTIVE: To generate high-resolution maps of the viscoelastic properties of human brain parenchyma for presurgical quantitative assessment in glioblastoma (GB. METHODS: Twenty-two GB patients underwent routine presurgical work-up supplemented by additional multifrequency magnetic resonance elastography. Two three-dimensional viscoelastic parameter maps, magnitude |G*|, and phase angle φ of the complex shear modulus were reconstructed by inversion of full wave field data in 2-mm isotropic resolution at seven harmonic drive frequencies ranging from 30 to 60 Hz. RESULTS: Mechanical brain maps confirmed that GB are composed of stiff and soft compartments, resulting in high intratumor heterogeneity. GB could be easily differentiated from healthy reference tissue by their reduced viscous behavior quantified by φ (0.37±0.08 vs. 0.58±0.07. |G*|, which in solids more relates to the material's stiffness, was significantly reduced in GB with a mean value of 1.32±0.26 kPa compared to 1.54±0.27 kPa in healthy tissue (P = 0.001. However, some GB (5 of 22 showed increased stiffness. CONCLUSION: GB are generally less viscous and softer than healthy brain parenchyma. Unrelated to the morphology-based contrast of standard magnetic resonance imaging, elastography provides an entirely new neuroradiological marker and contrast related to the biomechanical properties of tumors.

  2. Effect of Calcifications on Breast Ultrasound Shear Wave Elastography: An Investigational Study.

    Directory of Open Access Journals (Sweden)

    Adriana Gregory

    Full Text Available To investigate the effects of macrocalcifications and clustered microcalcifications associated with benign breast masses on shear wave elastography (SWE.SuperSonic Imagine (SSI and comb-push ultrasound shear elastography (CUSE were performed on three sets of phantoms to investigate how calcifications of different sizes and distributions influence measured elasticity. To demonstrate the effect in vivo, three female patients with benign breast masses associated with mammographically-identified calcifications were evaluated by CUSE.Apparent maximum elasticity (Emax estimates resulting from individual macrocalcifications (with diameters of 2mm, 3mm, 5mm, 6mm, 9mm, 11mm, and 15mm showed values over 50 kPa for all cases, which represents more than 100% increase over background (~21kPa. We considered a 2cm-diameter circular region of interest for all phantom experiments. Mean elasticity (Emean values varied from 26 kPa to 73 kPa, depending on the macrocalcification size. Highly dense clusters of microcalcifications showed higher Emax values than clusters of microcalcification with low concentrations, but the difference in Emean values was not significant.Our results demonstrate that the presence of large isolated macrocalcifications and highly concentrated clusters of microcalcifications can introduce areas with apparent high elasticity in SWE. Considering that benign breast masses normally have significantly lower elasticity values than malignant tumors, such areas with high elasticity appearing due to presence of calcification in benign breast masses may lead to misdiagnosis.

  3. Evaluation of the severity of capsular contracture using elastography after breast implant reconstruction.

    Science.gov (United States)

    Sowa, Yoshihiro; Yokota, Isao; Itsukage, Sizu; Nakatsukasa, Katsuhiko; Sakaguchi, Koichi; Taguchi, Tetsuya; Numajiri, Toshiaki

    2017-01-01

    Capsular contracture around implants is a common complication after breast reconstruction. Strain elastography (STE) and shear-wave elastography (SWE) are noninvasive imaging techniques that can measure tissue stiffness and thickness of the capsule. The purposes of the study were to compare STE and SWE for measurement of capsular contracture after breast implant reconstruction using intra-class correlation coefficients (ICCs) and to investigate the correlation of these data with the Baker score, which is the most frequently used clinical staging scale for capsule contracture. The subjects were 20 patients (27 implants) who underwent breast reconstruction. The reproducibility of SWE (ICC: 0.878) was higher than that of STE (ICC: 0.724) for measurement of capsular contracture. The correlation coefficient between measurements with the two methods was low (r = 0.6788). The Baker score had a higher correlation with measurements with SWE (r = 0.8124) compared to those with STE (r = 0.6983). These results suggest that SWE is a better tool for assessment of the degree of capsule contracture surrounding implants after breast reconstruction.

  4. Tabletop magnetic resonance elastography for the measurement of viscoelastic parameters of small tissue samples

    Science.gov (United States)

    Ipek-Ugay, Selcan; Drießle, Toni; Ledwig, Michael; Guo, Jing; Hirsch, Sebastian; Sack, Ingolf; Braun, Jürgen

    2015-02-01

    We demonstrate the feasibility of low-cost tabletop MR elastography (MRE) for quantifying the complex shear modulus G∗ of small soft biological tissue samples as provided by pathologists. The MRE system was developed based on a tabletop MRI scanner equipped with a 0.5 T permanent magnet and a tissue sample holder mounted to a loudspeaker. A spin echo sequence was enhanced with motion-encoding gradients of 250 mT/m amplitude synchronized to acoustic vibration frequencies. Shear wave images suitable for elastography were acquired between vibration frequencies of 0.5 and 1 kHz in agarose, ultrasound gel, porcine liver, porcine skeletal muscle, and bovine heart with a spatial resolution of 234 μm pixel edge length. The measured frequency dependence of G∗ agreed well with previous work based on high-field MR systems. The ratio between loss and storage moduli was highest in liver and ultrasound gel, followed by muscle tissue and agarose gel while ultrasound gel and liver showed similarly low storage moduli compared to the other samples. The shear wave to noise ratio is an important imaging criteria for MRE and was about 4.2 times lower for the preliminary setup of the 0.5 T tabletop system compared to a 7 T animal scanner. In the future, the new tabletop MRE system may serve as a low cost device for preclinical research on the correlation of viscoelastic parameters with histopathology of biological samples.

  5. Magnetic resonance imaging and transient elastography in the management of Nonalcoholic Fatty Liver Disease (NAFLD).

    Science.gov (United States)

    Han, Ma Ai Thanda; Saouaf, Rola; Ayoub, Walid; Todo, Tsuyoshi; Mena, Edward; Noureddin, Mazen

    2017-04-01

    Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease and cirrhosis worldwide and the second most common cause of liver transplantation in major medical centers. Because liver steatosis and fibrosis severity are related to disease morbidity and mortality, the extent of disease, and disease progression, they need to be assessed and monitored. In addition, innovation with new drug developments requires disease staging and monitoring in both phase 2 and 3 clinical trials. Currently, disease assessment in both clinical practice and research is mostly performed by liver biopsy, an invasive, procedure with risks. Noninvasive, highly accurate tests are needed that could be used in clinical trials as surrogate endpoints and in clinical practice for monitoring patients. Area Covered: We discuss noninvasive tests, transient elastography (TE) with controlled attenuation parameter (CAP), magnetic resonance imaging (MRI), and MR elastography (MRE), summarize the available evidence of their usefulness for assessing steatosis and fibrosis. Therefore they could be used as clinical trials outcomes and in disease monitoring in clinical practice. Expert Commentary: TE with CAP, MRI and MRE are highly accurate noninvasive diagnostic tools for quantifying hepatic steatosis and fibrosis. Therefore they could be used as clinical trials outcomes and in disease monitoring in clinical practice.

  6. Maximizing the endosonography: The role of contrast harmonics, elastography and confocal endomicroscopy.

    Science.gov (United States)

    Seicean, Andrada; Mosteanu, Ofelia; Seicean, Radu

    2017-01-07

    New technologies in endoscopic ultrasound (EUS) evaluation have been developed because of the need to improve the EUS and EUS-fine needle aspiration (EUS-FNA) diagnostic rate. This paper reviews the principle, indications, main literature results, limitations and future expectations for each of the methods presented. Contrast-enhanced harmonic EUS uses a low mechanical index and highlights slow-flow vascularization. This technique is useful for differentiating solid and cystic pancreatic lesions and assessing biliary neoplasms, submucosal neoplasms and lymph nodes. It is also useful for the discrimination of pancreatic masses based on their qualitative patterns; however, the quantitative assessment needs to be improved. The detection of small solid lesions is better, and the EUS-FNA guidance needs further research. The differentiation of cystic lesions of the pancreas and the identification of the associated malignancy features represent the main indications. Elastography is used to assess tissue hardness based on the measurement of elasticity. Despite its low negative predictive value, elastography might rule out the diagnosis of malignancy for pancreatic masses. Needle confocal laser endomicroscopy offers useful information about cystic lesions of the pancreas and is still under evaluation for use with solid pancreatic lesions of lymph nodes.

  7. Preliminary results of a new tool to evaluate cavernous body fibrosis following radical prostatectomy: penile elastography.

    Science.gov (United States)

    Hamidi, N; Altinbas, N K; Gokce, M I; Suer, E; Yagci, C; Baltaci, S; Turkolmez, K

    2017-09-01

    Development of cavernous tissue fibrosis due to neurovascular bundle damage during radical prostatectomy has been shown in many trials with invasive methods. In this study, we evaluated the changes in cavernous tissue elasticity by elastography in patients who underwent radical prostatectomy with or without neurovascular bundle preservation. Data from 65 patients underwent open retropubic radical prostatectomy between April 2014 and December 2015 was collected prospectively. Patients were grouped with respect to nerve-sparing status (non-, unilateral, and bilateral nerve sparing). International Index of Erectile Function scores, penile lengths, and elasticity scores were recorded at preoperative and postoperative follow-up visits (at 3rd and 6th months). The primary endpoint of the study was to evaluate the changes of the elasticity scores in all groups. Elasticity scores were measured with real-time elastography by a single experienced radiologist. Mean age, baseline total testosterone level, IIEF-5 score, elasticity scores of the cavernous body, and penile length were comparable in all groups. At postoperative 3rd and 6th months, statistically significant higher (in favor for fibrosis) mean cavernous body elasticity scores (p = 0.0001), lower mean IIEF-5 scores (p = 0.0001), and shorter penile lengths (p cavernous tissue fibrosis. © 2017 American Society of Andrology and European Academy of Andrology.

  8. Ultrahigh resolution optical coherence elastography combined with a rigid micro-endoscope (Conference Presentation)

    Science.gov (United States)

    Fang, Qi; Curatolo, Andrea; Wijesinghe, Philip; Hamzah, Juliana; Ganss, Ruth; Noble, Peter B.; Karnowski, Karol; Sampson, David D.; Kim, Jun Ki; Lee, Wei M.; Kennedy, Brendan F.

    2017-02-01

    The mechanical forces that living cells experience represent an important framework in the determination of a range of intricate cellular functions and processes. Current insight into cell mechanics is typically provided by in vitro measurement systems; for example, atomic force microscopy (AFM) measurements are performed on cells in culture or, at best, on freshly excised tissue. Optical techniques, such as Brillouin microscopy and optical elastography, have been used for ex vivo and in situ imaging, recently achieving cellular-scale resolution. The utility of these techniques in cell mechanics lies in quick, three-dimensional and label-free mechanical imaging. Translation of these techniques toward minimally invasive in vivo imaging would provide unprecedented capabilities in tissue characterization. Here, we take the first steps along this path by incorporating a gradient-index micro-endoscope into an ultrahigh resolution optical elastography system. Using this endoscope, a lateral resolution of 2 µm is preserved over an extended depth-of-field of 80 µm, achieved by Bessel beam illumination. We demonstrate this combined system by imaging stiffness of a silicone phantom containing stiff inclusions and a freshly excised murine liver tissue. Additionally, we test this system on murine ribs in situ. We show that our approach can provide high quality extended depth-of-field images through an endoscope and has the potential to measure cell mechanics deep in tissue. Eventually, we believe this tool will be capable of studying biological processes and disease progression in vivo.

  9. Elastic Characteristics of the Normal Achilles Tendon Assessed by Virtual Touch Imaging Quantification Shear Wave Elastography.

    Science.gov (United States)

    Fu, Shuai; Cui, Ligang; He, Xiaoxi; Sun, Yang

    2016-09-01

    To assess the elastic properties of the normal Achilles tendon in different age groups by Virtual Touch imaging quantification (VTIQ; Siemens Medical Solutions, Malvern, PA) shear wave elastography. A total of 326 healthy volunteers older than 18 years were divided into different groups by sex and age. The thickness, shear wave velocity (SWV) in sagittal and axial sections, and anisotropic coefficient of the Achilles tendon in a state of relaxation were obtained by conventional sonography and Virtual Touch imaging quantification elastography. These parameters were compared in different age and sex groups, and their correlations with age were evaluated. The thickness of the Achilles tendon in men and women increased gradually with age, and it was larger in men than in women in each age group (P tendon in the sagittal section decreased slightly with age, but the sagittal and axial SWVs and anisotropic coefficient had no significant differences among different age groups (P > .05), and they also had no significant differences between men and women within any group (P > .05). The SWVs in the sagittal and axial sections and anisotropic coefficient had no correlation with age. Intraclass correlation coefficients for sagittal and axial SWVs obtained by 2 independent observers were 0.923 and 0.870, respectively. The thickness of the Achilles tendon increased gradually with age. We confirmed that tendinous elastographic anisotropy and the stiffness of the tendon had no significant correlation with age.

  10. Application of Eshelby's Solution to Elastography for Diagnosis of Breast Cancer.

    Science.gov (United States)

    Shin, Bonghun; Gopaul, Darindra; Fienberg, Samantha; Kwon, Hyock Ju

    2016-03-01

    Eshelby's solution is the analytical method that can derive the elastic field within and around an ellipsoidal inclusion embedded in a matrix. Since breast tumor can be regarded as an elastic inclusion with different elastic properties from those of surrounding matrix when the deformation is small, we applied Eshelby's solution to predict the stress and strain fields in the breast containing a suspicious lesion. The results were used to investigate the effectiveness of strain ratio (SR) from elastography in representing modulus ratio (MR) that may be the meaningful indicator of the malignancy of the lesion. This study showed that SR significantly underestimates MR and is varied with the shape and the modulus of the lesion. Based on the results from Eshelby's solution and finite element analysis (FEA), we proposed a surface regression model as a polynomial function that can predict the MR of the lesion to the matrix. The model has been applied to gelatin-based phantoms and clinical ultrasound images of human breasts containing different types of lesions. The results suggest the potential of the proposed method to improve the diagnostic performance of breast cancer using elastography. © The Author(s) 2015.

  11. Effect of Calcifications on Breast Ultrasound Shear Wave Elastography: An Investigational Study

    Science.gov (United States)

    Gregory, Adriana; Mehrmohammadi, Mohammad; Denis, Max; Bayat, Mahdi; Stan, Daniela L.; Fatemi, Mostafa; Alizad, Azra

    2015-01-01

    Purpose To investigate the effects of macrocalcifications and clustered microcalcifications associated with benign breast masses on shear wave elastography (SWE). Methods SuperSonic Imagine (SSI) and comb-push ultrasound shear elastography (CUSE) were performed on three sets of phantoms to investigate how calcifications of different sizes and distributions influence measured elasticity. To demonstrate the effect in vivo, three female patients with benign breast masses associated with mammographically-identified calcifications were evaluated by CUSE. Results Apparent maximum elasticity (Emax) estimates resulting from individual macrocalcifications (with diameters of 2mm, 3mm, 5mm, 6mm, 9mm, 11mm, and 15mm) showed values over 50 kPa for all cases, which represents more than 100% increase over background (~21kPa). We considered a 2cm-diameter circular region of interest for all phantom experiments. Mean elasticity (Emean) values varied from 26 kPa to 73 kPa, depending on the macrocalcification size. Highly dense clusters of microcalcifications showed higher Emax values than clusters of microcalcification with low concentrations, but the difference in Emean values was not significant. Conclusions Our results demonstrate that the presence of large isolated macrocalcifications and highly concentrated clusters of microcalcifications can introduce areas with apparent high elasticity in SWE. Considering that benign breast masses normally have significantly lower elasticity values than malignant tumors, such areas with high elasticity appearing due to presence of calcification in benign breast masses may lead to misdiagnosis. PMID:26368939

  12. The Essentials of Parathyroid Hormone Venous Sampling

    Energy Technology Data Exchange (ETDEWEB)

    Taslakian, Bedros, E-mail: btaslakian@gmail.com [NYU Langone Medical Center, Department of Radiology, NYU School of Medicine (United States); Trerotola, Scott O., E-mail: streroto@uphs.upenn.edu [Perelman School of Medicine of the University of Pennsylvania, Department of Radiology (United States); Sacks, Barry, E-mail: bsacks@bidmc.harvard.edu [Beth Israel Deaconess Medical Center, Department of Interventional Radiology (United States); Oklu, Rahmi, E-mail: oklu.rahmi@mayo.edu [Mayo Clinic, Department of Interventional Radiology (United States); Deipolyi, Amy, E-mail: deipolya@mskcc.org [Memorial Sloan Kettering Cancer Center, Department of Radiology (United States)

    2017-01-15

    Hyperparathyroidism is an excess of parathyroid hormone in the blood due to over-activity of one or more parathyroid gland. Localization of abnormal glands with noninvasive imaging modalities, such as technetium sestamibi scan and cross-sectional imaging, has a high success rate. Parathyroid venous sampling is performed for patients with persistent or recurrent disease after previous parathyroid surgery, when repeat noninvasive imaging studies are negative or discordant. The success of invasive localization studies and results interpretation is dependent on the interventional radiologist’s understanding of the normal and ectopic anatomic locations of parathyroid glands, as well as their blood supply and venous drainage. Anatomic and technical considerations for selective parathyroid venous sampling are reviewed.

  13. Central Venous Catheter-Related Hydrothorax

    Directory of Open Access Journals (Sweden)

    Se Hun Kim

    2015-11-01

    Full Text Available This report describes a case of 88-year-old women who developed central venous catheter-related bilateral hydrothorax, in which left pleural effusion, while right pleural effusion was being drained. The drainage prevented accumulation of fluid in the right pleural space, indicating that there was neither extravasation of infusion fluid nor connection between the two pleural cavities. The only explanation for bilateral hydrothorax in this case is lymphatic connections. Although vascular injuries by central venous catheter can cause catheter-related hydrothorax, it is most likely that the positioning of the tip of central venous catheter within the lymphatic duct opening in the right sub-clavian-jugular confluence or superior vena cava causes the catheter-related hydrothorax. Pericardial effusion can also result from retrograde lymphatic flow through the pulmonary lymphatic chains.

  14. Noninvasive measurement of central venous pressure

    Science.gov (United States)

    Webster, J. G.; Mastenbrook, S. M., Jr.

    1972-01-01

    A technique for the noninvasive measurement of CVP in man was developed. The method involves monitoring venous velocity at a point in the periphery with a transcutaneous Doppler ultrasonic velocity meter while the patient performs a forced expiratory maneuver. The idea is the CVP is related to the value of pressure measured at the mouth which just stops the flow in the vein. Two improvements were made over the original procedure. First, the site of venous velocity measurement was shifted from a vein at the antecubital fossa (elbow) to the right external jugular vein in the neck. This allows for sensing more readily events occurring in the central veins. Secondly, and perhaps most significantly, a procedure for obtaining a curve of relative mean venous velocity vs mouth pressure was developed.

  15. Complications of central venous stenosis due to permanent central venous catheters in children on hemodialysis.

    Science.gov (United States)

    Rinat, Choni; Ben-Shalom, Efrat; Becker-Cohen, Rachel; Feinstein, Sofia; Frishberg, Yaacov

    2014-11-01

    Central venous catheters are frequently used as access for hemodialysis (HD) in children. One of the known complications is central venous stenosis. Although this complication is not rare, it is often asymptomatic and therefore unacknowledged. Superior vena cava (SVC) stenosis is obviously suspected in the presence of upper body edema, but several other signs and symptoms are often unrecognized as being part of this syndrome. We describe four patients with various manifestations of central venous stenosis and SVC syndrome. These sometimes life- or organ-threatening conditions include obstructive sleep apnea, unresolving stridor, increased intracranial pressure, increased intraocular pressure, right-sided pleural effusion, protein-losing enteropathy and lymphadenopathy. The temporal relationship of these complications associated with the use of central venous catheters and documentation of venous stenosis, together with their resolution after alleviation of high venous pressure, points to a causal role. We suggest pathophysiological mechanisms for the formation of each of these complications. In patients with occlusion of the SVC, various unexpected clinical entities can be caused by high central venous pressure. As often the etiology is not obvious, a high index of suspicion is needed as in some cases prompt alleviation of the high pressure is mandatory.

  16. Usefulness of ultrasound elastography in reducing the number of Breast Imaging Reporting and Data System category 3 lesions on ultrasonography

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Nariya; Lim, Ji He; Moon, Woo Kyung [Dept. of Radiology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2014-04-15

    To evaluate the negative predictive value (NPV) of ultrasound (US) elastography for non-palpable Breast Imaging Reporting and Data System (BI-RADS) category 3 lesions on ultrasonography and to determine whether US elastography is helpful in reducing the number of BI-RADS category 3 lesions on ultrasonography. Two hundred seventy-six consecutive, non-palpable BI-RADS category 3 lesions in 256 women who underwent US elastography and US-guided core biopsy, and who had at least 12 months of follow-up data, comprised our study group. The BI-RADS final assessment category and elasticity score were prospectively and independently classified. The rate of malignancy and NPV according to the elasticity score were analysed. We also investigated whether there was a subset of BI-RADS category 3 lesions that were of benign histology but negative on elastography. Of the 276 non-palpable BI-RADS category 3 lesions, three lesions (1.0%) were finally confirmed as ductal carcinomas in situ. No cancers were found in the remaining 273 lesions with benign biopsy histology at a mean follow-up of 39.4 months (range, 12 to 72 months). The NPV of a negative elasticity score (elasticity score of 1) was 99.3% (165 of 166). If BI-RADS category 3 lesions showing a negative elasticity score were downgraded to BI-RADS category 2, 60.4% (165 of 273) of them with benign histology could have been safely followed without biopsy with an increased malignancy rate from 1% (3 of 276) to 1.8% (2 of 110), which is not significantly higher (P=0.626). US elastography has the potential to reduce the number of BI-RADS category 3 lesions on ultrasonography.

  17. Clinical features and diagnosis of venous thrombosis

    Energy Technology Data Exchange (ETDEWEB)

    Hirsh, J.; Hull, R.D.; Raskob, G.E.

    1986-12-01

    The clinical diagnosis of venous thrombosis is inaccurate because the clinical findings are both insensitive and nonspecific. The sensitivity of clinical diagnosis is low because many potentially dangerous venous thrombi are clinically silent. The specificity of clinical diagnosis is low because the symptoms or signs of venous thrombosis all can be caused by nonthrombotic disorders. A current approach to the diagnosis of clinically suspected venous thrombosis favors the use of impedance plethysmography over Doppler ultrasonography as the main test for this disorder. This is because impedance plethysmography is precise and objective, whereas the interpretation of Doppler ultrasonography is subjective and requires considerable skill and experience to form reliable diagnoses. The use of serial impedance plethysmography has been evaluated recently in a prospective study. The rationale of repeated impedance plethysmography evaluation is based on the premise that calf vein thrombi are only clinically important when they extend into the proximal veins, at which point detection with impedance plethysmography is possible. Therefore, by performing repeated examinations with impedance plethysmography in patients with clinically suspected venous thrombosis, it is possible to identify patients with extending calf vein thrombosis who can be treated appropriately. Impedance plethysmography is performed immediately on referral; if it is positive in the absence of clinical conditions that are known to produce falsely positive results, the diagnosis of venous thrombosis is established, and the patient is treated accordingly. If the result of the initial impedance plethysmography evaluation is negative, anticoagulant therapy is withheld, and impedance plethysmography is repeated the following day, again on day 5 to 7 and on day 10 to 14. 87 references.

  18. Admission Hyperglycemia and Clinical Outcome in Cerebral Venous Thrombosis

    NARCIS (Netherlands)

    Zuurbier, Susanna M.; Hiltunen, Sini; Tatlisumak, Turgut; Peters, Guusje M.; Silvis, Suzanne M.; Haapaniemi, Elena; Kruyt, Nyika D.; Putaala, Jukka; Coutinho, Jonathan M.

    2016-01-01

    Background and Purpose-Admission hyperglycemia is associated with poor clinical outcome in ischemic and hemorrhagic stroke. Admission hyperglycemia has not been investigated in patients with cerebral venous thrombosis. Methods-Consecutive adult patients with cerebral venous thrombosis were included

  19. Venous thrombosis: the history of knowledge.

    Science.gov (United States)

    Mannucci, P M

    2002-01-01

    Venous thrombosis is a frequent disease. It is surprising, therefore, that no case truly compatible with a diagnosis of venous thrombosis was apparently reported in the antiquity. There is no case that could be reasonably attributed to a venous thrombus in the writings of Hippocrates, Galenus, Celius Aurelianus, Ibn an-Nafiz, Avicenna and others. Venous thrombosis is not among the many diseases mentioned in the Bible. The term "leucophlegmasia", first used by Hippocrates and then by Celius Aurelianus, refers to cases of bilateral leg edema, most likely due to conditions such as heart failure, liver cirrhosis and renal insufficiency. Nothing compatible with a diagnosis of venous thrombosis can be found in pieces of art from ancient Egypt, Greece, Rome, Persia and South America. While in these sources there are sometimes representations of varicose veins and ulcers, unilateral leg edema or other pictures compatible with venous thrombosis are not featured. The first well documented case of venous thrombosis is depicted in a beautifully illustrated manuscript written in the 13th century and currently preserved in Paris at the Bibliothèque Nationale (MS Fr 2829, Folio 87). The manuscript describes the case of a young man from Normandy named Raoul who at the age of twenty developed unilateral edema in the right ankle that subsequently extended up to the thigh, with no obvious symptoms in the contralateral leg. Raoul was advised to visit the tomb of Saint Louis who was buried in the church of Saint Denis, where the patient spent several days confessing his sins and praying the saint. Afterwards he chose to collect the dust accumulating below the stone that covered the tomb and to apply it on the fistulae and ulcers of his foot. The openings stopped running and were filled with flesh. He was first obliged to use crutches but subsequently he could walk with a cane, to be eventually able to dispose of all devices, even though his foot throbbed a little. Raoul was cured as

  20. Management of Peripheral and Truncal Venous Injuries

    Directory of Open Access Journals (Sweden)

    Triantafillos G. Giannakopoulos

    2017-08-01

    Full Text Available Civilian injuries are increasing according to the World Health Organization, and this is attributed mainly to road traffic accidents and urban interpersonal violence. Vascular injuries are common in these scenarios and are associated with high morbidity and mortality rates. Associated peripheral venous trauma is less likely to lead to death and controversy remains whether ligation or repair should be the primary approach. Conversely, non-compressible truncal venous insult can be lethal due to exsanguination, thus a high index of suspicion is crucial. Operative management is demanding with fair results but recent endovascular adjuncts demonstrate promising results and seem to be the way forward for these serious conditions.

  1. Jugular Venous Catheterization: A Case of Knotting

    Directory of Open Access Journals (Sweden)

    E. Erkılıç

    2015-01-01

    Full Text Available A 79-year-old woman, diagnosed for cancer of the ovary, had a central catheter that was placed with difficulty through the right internal jugular vein intraoperatively. After oophorectomy, it was realized that the catheter was knotted. Thus, the central venous catheter was removed successfully using a traction technique in the operating room. Central venous catheter use may result in various complications, although it has been used as an invasive method for hemodynamic monitoring and fluid and drug infusion. Here, we present catheter knotting in a case with solutions for this complication, under literature review.

  2. Differentiating benign from malignant solid breast masses: value of shear wave elastography according to lesion stiffness combined with greyscale ultrasound according to BI-RADS classification

    National Research Council Canada - National Science Library

    Evans, A; Whelehan, P; Thomson, K; Brauer, K; Jordan, L; Purdie, C; McLean, D; Baker, L; Vinnicombe, S; Thompson, A

    2012-01-01

    The aim of this study was to assess the performance of shear wave elastography combined with BI-RADS classification of greyscale ultrasound images for benign/malignant differentiation in a large group of patients...

  3. Venous capacity, venous refill time and the effectiveness of the calf muscle pump in normal subjects.

    Science.gov (United States)

    Barendsen, G J; van den Berg, J W

    1984-03-01

    With strain gauge plethysmography various procedures to assess the competence of the venous system in the lower leg were compared in 10 normal subjects. The reproducibility and ease of use were established, and normal values were obtained. It is concluded, that measurements in the sitting position are preferable to those in the standing position. To measure the venous capacity, the dependency test is the method of choice. Rhythmic exercise to assess the effectiveness of the calf muscle pump can be restricted to five successive contractions. The refill time after exercise is not a suitable parameter to assess the competence of the venous valves.

  4. Human cerebral venous outflow pathway depends on posture and central venous pressure

    DEFF Research Database (Denmark)

    Gisolf, J; van Lieshout, J J; van Heusden, K

    2004-01-01

    Internal jugular veins are the major cerebral venous outflow pathway in supine humans. In upright humans the positioning of these veins above heart level causes them to collapse. An alternative cerebral outflow pathway is the vertebral venous plexus. We set out to determine the effect of posture...... and during a Valsalva manoeuvre in both body positions, correlate highly with model simulation of the jugular cross-sectional area (R(2) = 0.97). The results suggest that the cerebral venous flow distribution depends on posture and CVP: in supine humans the internal jugular veins are the primary pathway...

  5. HIV-ASSOCIATED VENOUS THROMBOEMBOLISM

    Directory of Open Access Journals (Sweden)

    Michele Bibas

    2011-01-01

    Full Text Available

  1. Venous thromboembolism: awareness and practice of ...

    African Journals Online (AJOL)

    However, the high level of thromboprophylaxis practice appears doubtful because only a few of these physicians carry out VTE risk assessment for their patients as well as follow clinical guidelines on VTE thromboprophylaxis. Key words: Venous thromboembolism, deep vein thrombosis, pulmonary embolism, risk factor, ...

  2. Venous function after pharmacomechanical thrombolysis for ...

    African Journals Online (AJOL)

    Venous function after pharmacomechanical thrombolysis for extensive iliofemoral deep vein thrombosis. ... The PDF file you selected should load here if your Web browser has a PDF reader plug-in installed (for example, a recent version of Adobe Acrobat Reader). If you would like more information about how to print, save, ...

  3. Urethro-venous intravasation during urethrography

    African Journals Online (AJOL)

    J.M. Ratkal

    Abstract. Retrograde urethrography is a procedure used to evaluate urethral strictures. Urethro-venous intravasation, rarely seen during retrograde urethrography, can result in bacteremia, adverse reactions to contrast agents, renal failure and even pulmonary embolism. We report one such case of a male patient who ...

  4. Central venous pressure monitoring in clinical practice.

    Science.gov (United States)

    Scales, Katie

    This article provides an overview of central venous pressure (CVP) monitoring in clinical practice. It explores the underpinning anatomy and physiology, as well as the indications and means of access, for the procedure. The mechanics and practicalities of measuring CVP are discussed and information for troubleshooting is provided.

  5. Pediatric central venous access devices: nursing interventions

    Directory of Open Access Journals (Sweden)

    Duffy EA

    2017-05-01

    Full Text Available Elizabeth A Duffy, Kathryn N Nelson Department of Health Behavior and Biological Sciences, The University of Michigan School of Nursing, Ann Arbor, MI, USA Abstract: A central venous catheter (CVC is an indwelling catheter that provides permanent or temporary stable venous access for both acute and chronically ill pediatric patients. These catheters provide stable venous access that can be used for a variety of medical purposes including drawing blood, hemodynamic monitoring, infusion of intravenous medications, infusion of intravenous fluids, chemotherapy, blood products, and parenteral nutrition. Each day, nurses access and care for CVCs in infants, children, and adolescents; the precision of this care can prevent life-threatening complications. The purpose of this review and the case study is to highlight the importance and components of evidence-based nursing practice in pediatric CVC care. A historical perspective of CVC care is provided in conjunction with current national initiatives to improve patient outcomes for children with CVCs. Infection prevention, clinical practice guidelines, quality improvement, and evidence-based care bundles are discussed. Keywords: pediatric nursing, central venous catheters, central line-associated bloodstream infection, care bundles, pediatric case study 

  6. Venous infraction of developmental venous anomaly: A case report with perfusion imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jung Youn; Kim, Hye Jeong; Hyun, Su Jeong; Kim, Hee Yeong; Kim, Han Myun; Hwang, Ji Young; Hong, Hye Suk; Woo, Ji Young; Yang, Ik [Dept. of Radiology, Kangnam Sacred Heart Hospital, Hallym University College of Medicine, Seoul (Korea, Republic of); Kim, Eun Soo [Dept. of Radiology, Hallym University Sacred Heart Hospital, Hallym University College of Medicine, Anyang (Korea, Republic of)

    2017-06-15

    Developmental venous anomaly (DVA) is a common congenital venous malformation characterized by dilated medullary veins in caput medusa configuration and a draining vein. Despite the high incidence of DVAs, they are benign anatomic variations and rarely cause symptoms. Here, we report computed tomography and magnetic resonance imaging findings with perfusion images of acute infarction from underlying DVA in a 63-year-old female patient who presented with acute onset of neurologic symptoms and recovered without any neurologic deficit.

  7. Guided waves in pre-stressed hyperelastic plates and tubes: Application to the ultrasound elastography of thin-walled soft materials

    Science.gov (United States)

    Li, Guo-Yang; He, Qiong; Mangan, Robert; Xu, Guoqiang; Mo, Chi; Luo, Jianwen; Destrade, Michel; Cao, Yanping

    2017-05-01

    In vivo measurement of the mechanical properties of thin-walled soft tissues (e.g., mitral valve, artery and bladder) and in situ mechanical characterization of thin-walled artificial soft biomaterials in service are of great challenge and difficult to address via commonly used testing methods. Here we investigate the properties of guided waves generated by focused acoustic radiation force in immersed pre-stressed plates and tubes, and show that they can address this challenge. To this end, we carry out both (i) a theoretical analysis based on incremental wave motion in finite deformation theory and (ii) finite element simulations. Our analysis leads to a novel method based on the ultrasound elastography to image the elastic properties of pre-stressed thin-walled soft tissues and artificial soft materials in a non-destructive and non-invasive manner. To validate the theoretical and numerical solutions and demonstrate the usefulness of the corresponding method in practical measurements, we perform (iii) experiments on polyvinyl alcohol cryogel phantoms immersed in water, using the Verasonics V1 System equipped with a L10-5 transducer. Finally, potential clinical applications of the method have been discussed.

  8. Pycnogenol® in chronic venous insufficiency and related venous disorders.

    Science.gov (United States)

    Gulati, Om P

    2014-03-01

    The present review provides an update of the biological profile of Pycnogenol in the light of its use in the treatment of chronic venous insufficiency (CVI) and related venous disorders such as deep vein thrombosis (DVT), post-thrombotic syndrome, long haul air-travel-related leg oedema, venous ulcers and acute haemorrhoids. Pycnogenol is a French maritime pine bark extract produced from the outer bark of Pinus pinaster Ait. subsp. atlantica. Its strong antioxidant, anti-inflammatory and vasodilator activities, antithrombotic effects and collagen stabilizing properties make it uniquely able to target the multi facet pathophysiology of CVI and related venous disorders. Clinical studies have shown that it can reduce oedema of the legs in CVI, reduce the incidence of deep venous thrombosis during long haul flights and enhance the healing of venous ulcers and haemorrhoidal episodes by topical application and/or oral administration. This review highlights clinical research findings on the safety, compliance and efficacy of Pycnogenol, including its use in combination products. Copyright © 2013 John Wiley & Sons, Ltd.

  9. [Thrombophlebitis of venous sinuses in otitis media].

    Science.gov (United States)

    Kuczkowski, Jerzy

    2007-01-01

    Thrombophlebitis of dura venous sinuses is a rare intracranial complication of otitis media, which may be sometimes accompanied by symptoms or sepsis. Anatomical conditions and early diagnosis of this vascular complication determine the treatment modality. Aim of this study was the assessment of diagnostics and treatment of venous sinuses thrombophlebitis in acute and chronic otitis media considering anatomy and the venous sinuses and status of coagulation system. Otogenic thrombophlebitis may occur in lateral, transverse, upper and lower petrosal sinuses, and rarely in cavernous. In some cases thrombophlebitis proces may expand into brain or emissary mastoid veins. Lateral sinus thrombophlebitis in chronic otitis media usually appears clinically as septic fever, earache, and increasing neurologic signs. In acute otitis media when thrombophlebitis develops the patient complains about headache, high fever and visual acquity. Diagnosis of venous sinus thrombophlebitis is based on clinical signs, radiological imaging (CT scan, MRI), bacteriological examinations and laboratory biochemical tests. Contrast enhanced CT scan shows "delta sign". Septic thrombophlebitis sinus sigmoidei is caused by mixed bacterial flora. Surgical treatment in cases with septic thrombus consists of radical modiffied ear operation and lateral sinus exposure. Thrombectomy and jugular vein ligation is performed when sepsis or thrombus is present. Mastoidectomy and tympanic cavity drainage is performed in cases with lateral sinus thrombosis in acute mastoiditis. Intravenous antibiotics therapy should be continued for 2 weeks. Anticoagulants should be given taking into consideration parameters of coagulation system and the type of thrombus. Treatment results of venous sinuses thrombophlebitis are good if they are not accompanied by other intracranial complications.

  10. Transcriptome analysis reveals non-identical microRNA profiles between arterial and venous plasma

    Science.gov (United States)

    Xu, Guoheng; Geng, Bin; Cui, Qinghua

    2017-01-01

    Circulating microRNAs presented in venous plasma have been demonstrated as powerful biomarkers for the complex diseases like cancer. Nevertheless, those presented in arterial plasma remained largely unexplored. Here, using microarray technique, we compared microRNA expression profiles of the matched arterial and venous plasma samples from the same male rats. Though the microRNA profiles were largely similar, we identified 24 differentially expressed microRNAs, including 10 arterial highly expressed microRNAs and 14 venous highly expressed microRNAs. The differentially expressed microRNAs were validated by qRT-PCR. Computational analysis of these microRNAs and their targets indicated that arterial highly expressed microRNAs were overrepresented for functional terms like hematopoiesis and diseases like Crohn's Disease and leukemia; while venous highly expressed microRNAs were enriched for cell differentiation function, and diseases like distal myopathies and heart failure. Our analysis also suggested significant correlations between plasma microRNA expression and tissue microRNA expression. Four arterial highly expressed microRNAs also showed enriched expression in specific tissues and would be novel biomarker candidates. PMID:28212530

  11. The accuracy of the central venous blood gas for acid-base monitoring.

    Science.gov (United States)

    Walkey, Allan J; Farber, Harrison W; O'Donnell, Charles; Cabral, Howard; Eagan, Janet S; Philippides, George J

    2010-01-01

    Routine use of central venous blood gases (VBGs) may reduce complications from prolonged arterial cannulation. We investigated the reliability of the VBG as a substitute for arterial blood gas (ABG) in multiple care settings. We developed a VBG adjustment rule of ABG pH = VBG pH + 0.05, ABG CO(2) = VBG PCO(2) -5 mm Hg from prior studies and validated this relationship with simultaneous venous and arterial blood obtained from 187 medical/surgical intensive care, cardiac catheterization laboratory, and coronary care unit patients with central venous access. The overall accuracy of a normal adjusted VBG (aVBG) to predict a normal ABG was 90%. After adjustment, the mean systematic difference (bias) between ABG and VBG pH decreased from 0.035 +/- 0.02 to -0.015 +/- 0.02 and PCO(2) bias decreased from -4.5 +/- 3.5 to 0.5 +/- 3.5. Intraclass correlation coefficients for agreement improved after applying the adjustment rule to venous pH (from 0.84 to 0.93, P central VBG.

  12. Dynamics of liver stiffness values by means of transient elastography in patients with HCV liver cirrhosis undergoing interferon free treatment.

    Science.gov (United States)

    Sporea, Ioan; Lupușoru, Raluca; Mare, Ruxandra; Popescu, Alina; Gheorghe, Liana; Iacob, Speranța; Șirli, Roxana

    2017-06-01

    Liver stiffness (LS) measurement by Transient Elastography (TE) has been widely accepted as a tool for fibrosis assessment. The aim of this study was to assess LS dynamics in a group of patients with HCV liver cirrhosis after interferon free treatment (IFT). This two-center clinical trial included 225 patients with compensated HCV cirrhosis (all genotype 1b), who received IFT for 12 weeks. All patients were evaluated by means of TE at the beginning and at the end of treatment (EOT), and a subgroup (170 patients) also 12 weeks after EOT; all of them had sustained viral response (SVR). Reliable LS measurements (LSM) were defined as a median value of 10 valid LSM, with IQR /=60%. Both M and XL probes were used. For diagnosing cirrhosis we used a cut-off value of 12kPa as proposed by the Tsochatzis meta-analysis. We considered a decrease or increase of more than 10% in LSM as being significant. Out of 225 subjects, reliable measurements were obtained in 93.7%, so that the final analysis included 211 patients. The mean LS values decreased significantly after IFT: 26.4+/-11.7 vs. 23.5+/-13.3 kPa (p=0.01). Most patients, 59.2% (125/211) presented more than 10% decrease in LS values, 24.1% (51/211) had stable LS values, while in 16.4% (35/211) cases, the LS values increased. In the subgroup of 170 patients with LSM also performed 12 weeks after EOT (SVR), the mean LS values were significantly lower as compared to baseline: 21.3+/-11 kPa vs. 27.4+/-11.9 kPa (pvalues evaluated by TE significantly decreased after antiviral treatment at EOT and also 12 weeks after EOT as compared to baseline. Overall, about 60% of patients had LS values at EOT lower than at baseline, while 12 weeks after EOT about 75% of patients had LS values lower than at baseline.

  13. Advances in diagnosis and treatment of cerebral venous system diseases

    Directory of Open Access Journals (Sweden)

    Xiao-yun LIU

    2016-11-01

    Full Text Available Cerebral venous system diseases include cerebral venous thrombosis (CVT, venous sinus stenosis, carotid cavernous fistula (CCF, intracranial arteriovenous malformation (AVM and so on. In recent years, due to the rapid development of neuroimaging and interventional technology, more and more cerebral venous system diseases have been timely diagnosed and treated, such as magnetic resonance black-blood thrombus imaging (MRBTI in the diagnosis of CVT, stenting in the treatment of venous sinus stenosis, micro coil plus Onyx glue or covered stents in the treatment of CCF, which allow us to make a deeper recognition of cerebral venous system diseases. Therefore, this paper will introduce the latest diagnosis and treatment of cerebral venous system diseases. DOI: 10.3969/j.issn.1672-6731.2016.11.006

  14. In vivo estimation of elastic wave parameters using phase-stabilized swept source optical coherence elastography

    Science.gov (United States)

    Manapuram, Ravi Kiran; Aglyamov, Salavat R.; Monediado, Floredes M.; Mashiatulla, Maleeha; Li, Jiasong; Emelianov, Stanislav Y.; Larin, Kirill V.

    2012-10-01

    We report a highly sensitive method based on phase-stabilized swept source optical coherence elastography (PhS-SSOCE) to measure elastic wave propagation in soft tissues in vivo. The waves were introduced using a mechanical stimulus and were assessed using the phase response of the swept source optical coherence tomography signal. The technique was utilized to measure age-related changes in elastic flexural wave velocity and attenuation in mice cornea in vivo. Results demonstrate that the wave velocity increases with animal age, supporting previous observations that stiffness of mice cornea gradually increases with age. Our studies suggest that the PhS-SSOCE technique could potentially be used to obtain biomechanical properties of ocular tissues in vivo.

  15. Smooth muscle cells of penis in the rat: noninvasive quantification with shear wave elastography.

    Science.gov (United States)

    Zhang, Jia-Jie; Qiao, Xiao-Hui; Gao, Feng; Bai, Ming; Li, Fan; Du, Lian-Fang; Xing, Jin-Fang

    2015-01-01

    Smooth muscle cells (SMCs) of cavernosum play an important role in erection. It is of great significance to quantitatively analyze the level of SMCs in penis. In this study, we investigated the feasibility of shear wave elastography (SWE) on evaluating the level of SMCs in penis quantitatively. Twenty healthy male rats were selected. The SWE imaging of penis was carried out and then immunohistochemistry analysis of penis was performed to analyze the expression of alpha smooth muscle actin in penis. The measurement index of SWE examination was tissue stiffness (TS). The measurement index of immunohistochemistry analysis was positive area percentage of alpha smooth muscle actin (AP). Sixty sets of data of TS and AP were obtained. The results showed that TS was significantly correlated with AP and the correlation coefficient was -0.618 (p penis was successfully quantified in vivo with SWE. SWE can be used clinically for evaluating the level of SMCs in penis quantitatively.

  16. Measurement of Viscoelastic Properties of Condensed Matter using Magnetic Resonance Elastography

    Science.gov (United States)

    Gruwel, Marco L. H.; Latta, Peter; Matwiy, Brendon; Sboto-Frankenstein, Uta; Gervai, Patricia; Tomanek, Boguslaw

    2010-01-01

    Magnetic resonance elastography (MRE) is a phase contrast technique that provides a non-invasive means of evaluating the viscoelastic properties of soft condensed matter. This has a profound bio-medical significance as it allows for the virtual palpation of areas of the body usually not accessible to the hands of a medical practitioner, such as the brain. Applications of MRE are not restricted to bio-medical applications, however, the viscoelastic properties of prepackaged food products can also non-invasively be determined. Here we describe the design and use of a modular MRE acoustic actuator that can be used for experiments ranging from the human brain to pre-packaged food products. The unique feature of the used actuator design is its simplicity and flexibility, which allows easy reconfiguration.

  17. Corneal elastic anisotropy and hysteresis as a function of IOP assessed by optical coherence elastography

    Science.gov (United States)

    Li, Jiasong; Singh, Manmohan; Han, Zhaolong; Wu, Chen; Raghunathan, Raksha; Liu, Chih-Hao; Nair, Achuth; Noorani, Shezaan; Aglyamov, Salavat R.; Twa, Michael D.; Larin, Kirill V.

    2016-03-01

    The mechanical anisotropic properties of the cornea can be an important indicator for determining the onset and severity of different diseases and can be used to assess the efficacy of various therapeutic interventions, such as cross-linking and LASIK surgery. In this work, we introduce a noncontact method of assessing corneal mechanical anisotropy as a function of intraocular pressure (IOP) using optical coherence elastography (OCE). A focused air-pulse induced low amplitude (hysteresis of the cornea. The results show that the elastic anisotropy at the corneal of the apex of the cornea becomes more pronounced at higher IOPs, and that there are distinct radial angles of higher and lower stiffness. Due to the noncontact nature and small amplitude of the elastic wave, this method may be useful for characterizing the elastic anisotropy of ocular and other tissues in vivo completely noninvasively.

  18. Comparison of fractional wave equations for power law attenuation in ultrasound and elastography.

    Science.gov (United States)

    Holm, Sverre; Näsholm, Sven Peter

    2014-04-01

    A set of wave equations with fractional loss operators in time and space are analyzed. The fractional Szabo equation, the power law wave equation and the causal fractional Laplacian wave equation are all found to be low-frequency approximations of the fractional Kelvin-Voigt wave equation and the more general fractional Zener wave equation. The latter two equations are based on fractional constitutive equations, whereas the former wave equations have been derived from the desire to model power law attenuation in applications like medical ultrasound. This has consequences for use in modeling and simulation, especially for applications that do not satisfy the low-frequency approximation, such as shear wave elastography. In such applications, the wave equations based on constitutive equations are the viable ones. Copyright © 2014 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  19. Fuzzy-based classification of breast lesions using ultrasound echography and elastography.

    Science.gov (United States)

    Selvan, Shirley; Kavitha, M; Devi, S Shenbaga; Suresh, S

    2012-09-01

    Common breast lesions have different elasticity properties. Segmentation of contours of breast lesions from elastography and B mode images by incorporating variational level set method is involved in the proposed work. After segmentation, strain and shape features, such as differences in area, perimeter, and contour and width to height difference and solidity, as well as texture features like contrast, entropy, standard deviation, dissimilarity, homogeneity and energy, are estimated. A nonlinear fuzzy inference system is applied for classifying the breast lesions as benign cyst, benign solid mass, or malignant solid mass. Detection of malignant solid masses is our primary objective. A classification accuracy of 83% is obtained. One hundred percent sensitivity is reported. It can be concluded that the proposed fuzzy-based classification technique can be used as an aid for the automated detection of breast lesions.

  20. Characterization of nonlinear elasticity for biological tissue using quantitative optical coherence elastography

    Science.gov (United States)

    Qiu, Yi; Zaki, Farzana R.; Chandra, Namas; Chester, Shawn A.; Liu, Xuan

    2017-02-01

    We developed a quantitative optical coherence elastography (qOCE) system for nonlinear mechanical characterization of biological tissues. The fiber-optic probe of the qOCE system had an integrated Fabry-Perot force sensor. To perform mechanical characterization, the tissue was compressed uniaxially by the fiber-optic probe of the qOCE system. Using the optical coherence tomography (OCT) signal detected by a spectral domain OCT engine, we were able to simultaneously quantify the force exerted to the tissue and the displacement of tissue. The quantification of the force was critical for accurate assessment of the elastic behavior of tissue, because most biological tissues have nonlinear elastic behavior. We performed qOCE characterization on tissue mimicking phantoms and biological tissues. Our results demonstrated the capability of the qOCE system for linear and nonlinear assessment of tissue elasticity.

  1. In vivo optical elastography: stress and strain imaging of human skin lesions

    Science.gov (United States)

    Es'haghian, Shaghayegh; Gong, Peijun; Kennedy, Kelsey M.; Wijesinghe, Philip; Sampson, David D.; McLaughlin, Robert A.; Kennedy, Brendan F.

    2015-03-01

    Probing the mechanical properties of skin at high resolution could aid in the assessment of skin pathologies by, for example, detecting the extent of cancerous skin lesions and assessing pathology in burn scars. Here, we present two elastography techniques based on optical coherence tomography (OCT) to probe the local mechanical properties of skin. The first technique, optical palpation, is a high-resolution tactile imaging technique, which uses a complaint silicone layer positioned on the tissue surface to measure spatially-resolved stress imparted by compressive loading. We assess the performance of optical palpation, using a handheld imaging probe on a skin-mimicking phantom, and demonstrate its use on human skin. The second technique is a strain imaging technique, phase-sensitive compression OCE that maps depth-resolved mechanical variations within skin. We show preliminary results of in vivo phase-sensitive compression OCE on a human skin lesion.

  2. A preliminary study of shear wave elastography for the evaluation of unilateral palpable undescended testes.

    Science.gov (United States)

    Ucar, Ayse Kalyoncu; Alis, Deniz; Samanci, Cesur; Aslan, Mine; Habibi, Hatice Arioz; Dikici, Atilla Suleyman; Namdar, Yesim; Gultekin, Mehmet Hamza; Onal, Bulent; Adaletli, Ibrahim

    2017-01-01

    We sought to compare unilateral palpable undescended testes and contralateral descended testes using shear wave elastography (SWE) to show potential quantitative differences in elasticity patterns, which might reflect the histologic features. Approval for this prospective study was obtained from the local ethics committee. A total of 29 patients (mean age, 7.52 years; range, 1-18 years) with unilateral palpable undescended testes and contralateral descended testes were examined by greyscale ultrasonography and SWE between February 2015 and April 2016. The volume and the elasticity of each testicle were the main factors evaluated. There was no difference between undescended testes and contralateral descended testes in terms of volume. However, a significant difference was evident in SWE-derived quantitative data. SWE seems to be a useful sonographic technique to predict histologic features of the undescended testicle, which might replace testicular biopsy in modern management of the undescended testis. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  3. Shear wave elastography of the placenta in patients with gestational diabetes mellitus.

    Science.gov (United States)

    Yuksel, Mehmet Aytac; Kilic, Fahrettin; Kayadibi, Yasemin; Alici Davutoglu, Ebru; Imamoglu, Metehan; Bakan, Selim; Mihmanli, Ismail; Kantarci, Fatih; Madazli, Riza

    2016-07-01

    To evaluate placental elasticty in women with gestational diabetes mellitus (GDM) and non-diabetic controls. Thirty-three pregnant women with GDM according to the current criteria of the American Diabetes Association and 43 healthy pregnant women who were admitted to the antenatal clinic were recruited for this case-control study. Elasticity values of both the peripheral and the central parts of the placentas of the patients in both groups were determined by shear wave elastography (SWE) imaging. Mean elasticity values of both the central and the peripheral part of the placentas were significantly higher in GDM pregnancies (p  0.05). SWE imaging technology might provide a quantitative assessment of the morphological pathologies of placentas in pregnant women with GDM.

  4. Numerical simulations of magnetic resonance elastography using finite element analysis with a linear heterogeneous viscoelastic model.

    Science.gov (United States)

    Tomita, Sunao; Suzuki, Hayato; Kajiwara, Itsuro; Nakamura, Gen; Jiang, Yu; Suga, Mikio; Obata, Takayuki; Tadano, Shigeru

    2018-01-01

    Magnetic resonance elastography (MRE) is a technique to identify the viscoelastic moduli of biological tissues by solving the inverse problem from the displacement field of viscoelastic wave propagation in a tissue measured by MRI. Because finite element analysis (FEA) of MRE evaluates not only the viscoelastic model for a tissue but also the efficiency of the inversion algorithm, we developed FEA for MRE using commercial software called ANSYS, the Zener model for displacement field of a wave inside tissue, and an inversion algorithm called the modified integral method. The profile of the simulated displacement field by FEA agrees well with the experimental data measured by MRE for gel phantoms. Similarly, the value of storage modulus (i.e., stiffness) recovered using the modified integral method with the simulation data is consistent with the value given in FEA. Furthermore, applying the suggested FEA to a human liver demonstrates the effectiveness of the present simulation scheme.

  5. Improved Beamforming for Lateral Oscillations in Elastography Using Synthetic Aperture Imaging

    DEFF Research Database (Denmark)

    Liebgott, Hervé; Basarab, Adrian; Loizeau, Damien

    2007-01-01

    displacement estimation using images with lateral oscillations, it is necessary to reduce both the wavelength of the lateral oscillations and the width of the point spread function (PSF). This is reached in this work, by doing emit and receive beamforming using synthetic aperture data. We show......In this paper we present a beamforming technique based on synthetic aperture imaging that enables to improve the radio-frequency (RF) ultrasound images with lateral oscillations for lateral displacement estimation. As described in previous work, in order to increase the accuracy of the lateral...... that the wavelength of the lateral oscillations can be reduced by a factor 2, and the width of the PSF can be reduced by a factor radic2. We have used the images obtained by this beamforming technique for lateral displacement estimation in the field of elastography. We show that with this new approach it is possible...

  6. Liver stiffness using transient elastography is applicable to canines for hepatic disease models.

    Directory of Open Access Journals (Sweden)

    Antonio Rivero-Juárez

    Full Text Available BACKGROUND: The objectives of this study were to evaluate the best position and best exploration probe for determining liver stiffness (LS in dogs using transient liver elastography (TE. Thirteen dogs were used in the study. METHODOLOGY/PRINCIPAL FINDINGS: Morphometric measurements taken were thoracic circumference, weight and height. Elastographic measurements were taken in 4 anatomical positions using two different probes: medium (M and small (S. The exploration was considered correct when the success rate was above 60% and the interquartile range of the measurements did not exceed 30%. The best measurements were obtained in the middle of the 6th-9th intercostal spaces, with the dog in the left lateral position and using probe M for preference in adults and probe S mandatory for animals <2 years. The correlation between probes was 99%. Intra-observer variability showed an intra-class correlation of 97.6%. CONCLUSIONS/SIGNIFICANCE: TE is a technique that is reproducible in dogs.

  7. Predictors and Outcomes of Recurrent Venous Thromboembolism in Elderly Patients.

    Science.gov (United States)

    Lauber, Sandro; Limacher, Andreas; Tritschler, Tobias; Stalder, Odile; Méan, Marie; Righini, Marc; Aschwanden, Markus; Beer, Jürg Hans; Frauchiger, Beat; Osterwalder, Josef; Kucher, Nils; Lämmle, Bernhard; Cornuz, Jacques; Angelillo-Scherrer, Anne; Matter, Christian M; Husmann, Marc; Banyai, Martin; Staub, Daniel; Mazzolai, Lucia; Hugli, Olivier; Rodondi, Nicolas; Aujesky, Drahomir

    2018-01-04

    Little is known about predictors and outcomes of recurrent venous thromboembolism in elderly patients. We prospectively followed up 991 patients aged ≥65 years with acute venous thromboembolism in a multicenter Swiss cohort study. The primary outcome was symptomatic recurrent venous thromboembolism. We explored the association between baseline characteristics and treatments and recurrent venous thromboembolism using competing risk regression, adjusting for periods of anticoagulation as a time-varying co-variate. We also assessed the clinical consequences (case-fatality, localization) of recurrent venous thromboembolism. During a median follow-up period of 30 months, 122 patients developed recurrent venous thromboembolism, corresponding to a 3-year cumulative incidence of 14.8%. The case-fatality of recurrence was high (20.5%), particularly in patients with unprovoked (23%) and cancer-related venous thromboembolism (29%). After adjustment, only unprovoked venous thromboembolism (sub-hazard ratio [SHR] 1.67 compared to provoked venous thromboembolism; 95% confidence interval [CI] 1.00-2.77) and proximal deep vein thrombosis (SHR 2.41 compared to isolated distal deep vein thrombosis; 95% CI 1.07-5.38) were significantly associated with recurrence. Patients with initial pulmonary embolism were more likely to have another pulmonary embolism as a recurrent event than patients with deep vein thrombosis. Elderly patients with acute venous thromboembolism have a substantial long-term risk of recurrent venous thromboembolism and recurrence carries a high case-fatality rate. Only two factors, unprovoked venous thromboembolism and proximal deep vein thrombosis, were independently associated with recurrent venous thromboembolism, indicating that traditional risk factors for venous thromboembolism recurrence (e.g., cancer) may be less relevant in the elderly. Copyright © 2018. Published by Elsevier Inc.

  8. Transient Elastography to Assess the Cervical Ripening during Pregnancy: A Preliminary Study.

    Science.gov (United States)

    Peralta, Laura; Molina, Francisca Sonia; Melchor, Juan; Gómez, Luisa Fernanda; Massó, Paloma; Florido, Jesús; Rus, Guillermo

    2017-08-01

    Purpose  To explore the feasibility of transient elastography (TE) to quantify cervical stiffness changes during normal pregnancy and its spatial variability. Materials and Methods  TE was used to quantify the cervical stiffness in four anatomical regions. 42 women between 17 and 43 years of age and at 6 - 41 weeks of gestation were studied. The stiffness was related to gestational age at the time of examination, interval from ultrasound examination to delivery and cervical length to evaluate the potential of TE to assess cervical ripening. In addition, a sensitivity analysis based on Cronbach's alpha coefficient was carried out to assess the concordance between inter/intra-operator measurements. Results  There were significant correlations between cervical stiffness measured in the four regions with gestational age and the remaining time for delivery. Results confirm stiffness variability within the cervix. No significant association was found between cervical length and stiffness in the four ROIs. Associations between gestational age and remaining time for delivery with cervical length present weaker correlations than with cervical stiffness. The external part of the cervix was significantly softer than the internal one, and these stiffness values vary significantly in the anterior compared to the posterior cervix. The measurements taken by the same and by two different observers for different regions in the cervix were reliable and reproducible. Conclusion  It is feasible to objectively quantify the decrease of cervical stiffness correlated to gestational age. Transient elastography is a valuable promising tool to provide additional information on the process of cervical effacement to that obtained from digital examination and conventional ultrasound. Further studies are needed to assess the feasibility of the technique in obstetric clinical applications, such as prediction of preterm birth or success in labor induction. © Georg Thieme Verlag KG

  9. Strain wave elastography for evaluation of renal parenchyma in chronic kidney disease.

    Science.gov (United States)

    Menzilcioglu, M S; Duymus, M; Citil, S; Avcu, S; Gungor, G; Sahin, T; Boysan, S N; Altunoren, O; Sarica, A

    2015-06-01

    Chronic kidney disease (CKD) is an important and costly health problem in developed countries and has a tendency to progress to end-stage renal disease regardless of the aetiology. This progress ends in interstitial fibrosis, which decreases the elasticity of tissue. Elastography is a developing technique to assess tissue elasticity. The aim of this study was to determine the difference of strain index (SI) value of renal parenchyma between patients with CKD and healthy individuals. In addition, SI differences of inter-stages were studied. Toshiba (Toshiba Medical Systems Corporation, Otawara, Japan) Aplio™ 500 ultrasound device and 3.5- to 5.0-MHz convex probe were used for the elastography examinations. A total of 58 patients with CKD from nephrology and endocrinology clinics (30 males and 28 females; mean age, 56.14 ± 11.60 years) and 40 normal healthy individuals (19 males and 21 females; mean age, 51.70 ± 11.71 years) were included in this prospective study. The mean SI of normal healthy individuals and patients with CKD (regardless of stages) was 0.42 ± 0.30 and 1.81 ± 0.88, respectively (p < 0.001). SI values were not statistically significant among the CKD stages (except CKD Stages 1 and 3). The area under the receiver operating characteristic curve was 0.956 for SI. The optimal cut-off value for the prediction of CKD was 0.935 (sensitivity, 88% and specificity, 95%). SI value of sonoelastography can be used to differentiate patients with CKD and healthy individuals. Sonoelastography is an acceptable technique to approach patients with CKD, but we have not shown that it can reliably differentiate different stages. Determining a cut-off SI value between normal and diseased renal parenchyma can help in the diagnosis of CKD.