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Sample records for intravascular ultrasound measurements

  1. A new method to measure necrotic core and calcium content in coronary plaques using intravascular ultrasound radiofrequency-based analysis

    NARCIS (Netherlands)

    E.S. Shin (Eun-Seok); H.M. Garcia-Garcia (Hector); P.W.J.C. Serruys (Patrick)

    2010-01-01

    textabstractAlthough previous intravascular ultrasound (IVUS) radiofrequency-based analysis data showed acceptable reproducibility for plaque composition, measurements are not easily obtained, particularly that of lumen contour, because of the limited IVUS resolution. The purpose of this study was

  2. Mapping intravascular ultrasound controversies in interventional cardiology practice.

    Directory of Open Access Journals (Sweden)

    David Maresca

    Full Text Available Intravascular ultrasound is a catheter-based imaging modality that was developed to investigate the condition of coronary arteries and assess the vulnerability of coronary atherosclerotic plaques in particular. Since its introduction in the clinic 20 years ago, use of intravascular ultrasound innovation has been relatively limited. Intravascular ultrasound remains a niche technology; its clinical practice did not vastly expand, except in Japan, where intravascular ultrasound is an appraised tool for guiding percutaneous coronary interventions. In this qualitative research study, we follow scholarship on the sociology of innovation in exploring both the current adoption practices and perspectives on the future of intravascular ultrasound. We conducted a survey of biomedical experts with experience in the technology, the practice, and the commercialization of intravascular ultrasound. The collected information enabled us to map intravascular ultrasound controversies as well as to outline the dynamics of the international network of experts that generates intravascular ultrasound innovations and uses intravascular ultrasound technologies. While the technology is praised for its capacity to measure coronary atherosclerotic plaque morphology and is steadily used in clinical research, the lack of demonstrated benefits of intravascular ultrasound guided coronary interventions emerges as the strongest factor that prevents its expansion. Furthermore, most of the controversies identified were external to intravascular ultrasound technology itself, meaning that decision making at the industrial, financial and regulatory levels are likely to determine the future of intravascular ultrasound. In light of opinions from the responding experts', a wider adoption of intravascular ultrasound as a stand-alone imaging modality seems rather uncertain, but the appeal for this technology may be renewed by improving image quality and through combination with

  3. Multicenter assessment of the reproducibility of volumetric radiofrequency-based intravascular ultrasound measurements in coronary lesions that were consecutively stented

    NARCIS (Netherlands)

    Huisman, Jeroen; Egede, R.; Rdzanek, A.; Böse, D.; Erbel, R.; van der Palen, Jacobus Adrianus Maria; von Birgelen, Clemens

    2012-01-01

    To assess in a multicenter design the between-center reproducibility of volumetric virtual histology intravascular ultrasound (VH-IVUS) measurements with a semi-automated, computer-assisted contour detection system in coronary lesions that were consecutively stented. To evaluate the reproducibility

  4. Multicenter assessment of the reproducibility of volumetric radiofrequency-based intravascular ultrasound measurements in coronary lesions that were consecutively stented

    DEFF Research Database (Denmark)

    Huisman, Jennifer; Egede, Rasmus; Rdzanek, Adam

    2012-01-01

    To assess in a multicenter design the between-center reproducibility of volumetric virtual histology intravascular ultrasound (VH-IVUS) measurements with a semi-automated, computer-assisted contour detection system in coronary lesions that were consecutively stented. To evaluate the reproducibility...... of volumetric VH-IVUS measurements, experienced analysts of 4 European IVUS centers performed independent analyses (in total 8,052 cross-sectional analyses) to obtain volumetric data of 40 coronary segments (length 20.0 ± 0.3 mm) from target lesions prior to percutaneous intervention that were performed...... in the setting of stable (65%) or unstable angina pectoris (35%). Geometric and compositional VH-IVUS measurements were highly correlated for the different comparisons. Overall intraclass correlation for vessel, lumen, plaque volume and plaque burden was 0.99, 0.92, 0.96, and 0.83, respectively; for fibrous...

  5. Impact of analyzing fewer image frames per segment during offline volumetric radiofrequency based intravascular ultrasound measurements of target lesions prior to percutaneous coronary interventions

    NARCIS (Netherlands)

    Huisman, J.; Hartmann, M.; Hartmann, M.; Mintz, G.S.; van Houwelingen, G.K.; Stoel, M.G.; de Man, F.H.; Louwerenburg, H.; von Birgelen, Clemens

    2012-01-01

    In the present study, we evaluated the impact of a 50% reduction in number of image frames (every second frame) on the analysis time and variability of offline volumetric radiofrequency-based intravascular ultrasound (RF-IVUS) measurements in target lesions prior to percutaneous coronary

  6. Heterogeneous Intravascular Ultrasound Findings of Stent Thrombosis

    OpenAIRE

    Morofuji, Toru; Inaba, Shinji; Aisu, Hiroe; Takahashi, Kayo; Saito, Makoto; Higashi, Haruhiko; Yoshii, Toyofumi; Sumimoto, Takumi

    2017-01-01

    Objective The underlying mechanisms of stent thrombosis are not completely understood. Methods We experienced 12 definite stent thrombosis cases (1 early, 1 late, and 10 very late) at our hospital from July 2011 to April 2016 and evaluated the possible causes of stent thrombosis by intravascular ultrasound (IVUS). Results Five different potential morphological causes of stent thrombosis (neoatherosclerosis, stent malapposition, stent fracture, edge dissection, and stent underexpansion) were d...

  7. Mapping Intravascular Ultrasound Controversies in Interventional Cardiology Practice

    NARCIS (Netherlands)

    Maresca, D.; Adams, S.; Maresca, B.; Van der Steen, A.F.W.

    2014-01-01

    Intravascular ultrasound is a catheter-based imaging modality that was developed to investigate the condition of coronary arteries and assess the vulnerability of coronary atherosclerotic plaques in particular. Since its introduction in the clinic 20 years ago, use of intravascular ultrasound

  8. Rotational multispectral fluorescence lifetime imaging and intravascular ultrasound: bimodal system for intravascular applications

    Science.gov (United States)

    Ma, Dinglong; Bec, Julien; Yankelevich, Diego R.; Gorpas, Dimitris; Fatakdawala, Hussain; Marcu, Laura

    2014-01-01

    Abstract. We report the development and validation of a hybrid intravascular diagnostic system combining multispectral fluorescence lifetime imaging (FLIm) and intravascular ultrasound (IVUS) for cardiovascular imaging applications. A prototype FLIm system based on fluorescence pulse sampling technique providing information on artery biochemical composition was integrated with a commercial IVUS system providing information on artery morphology. A customized 3-Fr bimodal catheter combining a rotational side-view fiberoptic and a 40-MHz IVUS transducer was constructed for sequential helical scanning (rotation and pullback) of tubular structures. Validation of this bimodal approach was conducted in pig heart coronary arteries. Spatial resolution, fluorescence detection efficiency, pulse broadening effect, and lifetime measurement variability of the FLIm system were systematically evaluated. Current results show that this system is capable of temporarily resolving the fluorescence emission simultaneously in multiple spectral channels in a single pullback sequence. Accurate measurements of fluorescence decay characteristics from arterial segments can be obtained rapidly (e.g., 20 mm in 5 s), and accurate co-registration of fluorescence and ultrasound features can be achieved. The current finding demonstrates the compatibility of FLIm instrumentation with in vivo clinical investigations and its potential to complement conventional IVUS during catheterization procedures. PMID:24898604

  9. Intravascular Ultrasound Imaging of Peripheral Arteries as an Adjunct to Balloon Angioplasty and Atherectomy

    International Nuclear Information System (INIS)

    Korogi, Yukunori; Hirai, Toshinori; Takahashi, Mutsumasa

    1996-01-01

    This article reviews many of the applications of intravascular ultrasound (US) imaging for peripheral arterial diseases. In vitro studies demonstrate an excellent correlation between ultrasound measurements of lumen and plaque crossectional area compared with histologic sections. In vivo clinical studies reveal the enhanced diagnostic capabilities of this technology compared with angiography. Intravascular US imaging can provide valuable information on the degree, eccentricity, and histologic type of stenosis before intervention, and on the morphological changes in the arterial wall and the extent of excision after intervention. Intravascular US may also serve as a superior index for gauging the diameter of balloon, stent, laser probe, and/or atherectomy catheter appropriate for a proposed intervention. Significant new insights into the mechanisms of balloon angioplasty and atherectomy have been established by intravascular US findings. Intravascular US imaging has been shown to be a more accurate method than angiography for determining the cross-sectional area of the arterial lumen, and for assessing severity of stenosis. Quantitative assessment of the luminal cross-sectional area after the balloon dilatation should be more accurate than angiography as intimal tears or dissections produced by the dilatation may not be accurately evaluated with angiography. At the present time, intravascular US is still a controversial imaging technique. Outcome studies are currently being organized to assess the clinical value and cost effectiveness of intravascular ultrasound in the context of these interventional procedures

  10. A comparison between plaque-based and vessel-based measurement for plaque component using volumetric intravascular ultrasound radiofrequency data analysis.

    Science.gov (United States)

    Shin, Eun-Seok; Garcia-Garcia, Hector M; Garg, Scot; Serruys, Patrick W

    2011-04-01

    Although percent plaque components on plaque-based measurement have been used traditionally in previous studies, the impact of vessel-based measurement for percent plaque components have yet to be studied. The purpose of this study was therefore to correlate percent plaque components derived by plaque- and vessel-based measurement using intravascular ultrasound virtual histology (IVUS-VH). The patient cohort comprised of 206 patients with de novo coronary artery lesions who were imaged with IVUS-VH. Age ranged from 35 to 88 years old, and 124 patients were male. Whole pullback analysis was used to calculate plaque volume, vessel volume, and absolute and percent volumes of fibrous, fibrofatty, necrotic core, and dense calcium. The plaque and vessel volumes were well correlated (r = 0.893, P measurement was also highly correlated with vessel-based measurement. Therefore, the percent plaque component volume calculated by vessel volume could be used instead of the conventional percent plaque component volume calculated by plaque volume.

  11. Mechanical scanning in intravascular ultrasound imaging: Artifacts and driving mechanisms

    NARCIS (Netherlands)

    H. ten Hoff (H.); E.J. Gussenhoven (Elma); C.M. Korbijn (Carin); F. Mastik (Frits); C.T. Lancée (Charles); N. Bom (Klaas)

    1995-01-01

    textabstractObjective: Currently, intravascular ultrasound (US) imaging catheters are developed and produced to provide a complementary diagnostic method in the treatment of blood vessel obstructive disease. Typical catheter dimensions are a diameter of 1–2.5 mm and a length of 1–1.5 m. A real-time

  12. Renal denervation by intravascular ultrasound: Preliminary in vivo study

    Science.gov (United States)

    Sinelnikov, Yegor; McClain, Steve; Zou, Yong; Smith, David; Warnking, Reinhard

    2012-10-01

    Ultrasound denervation has recently become a subject of intense research in connection with the treatment of complex medical conditions including neurological conditions, development of pain management, reproduction of skin sensation, neuropathic pain and spasticity. The objective of this study is to investigate the use of intravascular ultrasound to produce nerve damage in renal sympathetic nerves without significant injury to the renal artery. This technique may potentially be used to treat various medical conditions, such as hypertension. The study was approved by the Institutional Animal Care and Use Committee. Ultrasound was applied to renal nerves of the swine model for histopathological evaluation. Therapeutic ultrasound energy was delivered circumferentially by an intravascular catheter maneuvered into the renal arteries. Fluoroscopic imaging was conducted pre-and post-ultrasound treatment. Animals were recovered and euthanized up to 30 hours post procedure, followed by necropsy and tissue sample collection. Histopathological examination showed evidence of extensive damage to renal nerves, characterized by nuclear pyknosis, hyalinization of stroma and multifocal hemorrhages, with little or no damage to renal arteries. This study demonstrates the feasibility of intravascular ultrasound as a minimally invasive renal denervation technique. Further studies are necessary to evaluate the long-term safety and efficacy of this technique and its related clinical significance.

  13. P-shaped Coiled Stator Ultrasound Motor for Rotating Intravascular Surgery Device

    Directory of Open Access Journals (Sweden)

    Toshinobu ABE

    2015-01-01

    Full Text Available The primary focus of this paper is the development of an ultra-miniature ultrasound motor for use in the human blood vessel. Since the size of the drive source for rotating the atherectomy device and intravascular ultrasonography system are large currently in practical use, it is installed outside the body, and the rotational power for the atherectomy device and intravascular ultrasonography system are transmitted through the long tortuous blood vessel. Such systems suffer from the problem that the rotation becomes non-uniform, and the problem that the available time is limited. We have therefore developed a P-shaped coiled stator ultrasound motor as a miniature ultrasound motor for rotating the ultrasound sensor for use in blood vessels in order to solve these problems. In this paper, we describe measurement of the torque, revolution speed, output power, efficiency, and particle motion on acoustic waveguide of the P-shaped coiled stator ultrasound motor.

  14. The clinical importance and prediction of steal following femoro-femoral cross-over bypass: study of the donor iliac artery by intravascular ultrasound, arteriography, duplex scanning and pressure measurements

    DEFF Research Database (Denmark)

    Vogt, K C; Rasmussen, J G; Schroeder, T V

    2000-01-01

    to evaluate the clinical significance of the steal phenomenon following femoro-femoral bypass, and whether the addition of intravascular ultrasound (IVUS) to the established examinations of the donor iliac artery can improve the prediction of patients who will develop steal.......to evaluate the clinical significance of the steal phenomenon following femoro-femoral bypass, and whether the addition of intravascular ultrasound (IVUS) to the established examinations of the donor iliac artery can improve the prediction of patients who will develop steal....

  15. Intravascular ultrasound based dose assessment in endovascular brachytherapy

    International Nuclear Information System (INIS)

    Catalano, Gianpiero; Tamburini, Vittorio; Colombo, Antonio; Nishida, Takahiro; Parisi, Giovanni; Mazzetta, Chiara; Orecchia, Roberto

    2003-01-01

    Background: the role of endovascular brachytherapy in restenosis prevention is well documented. Dose is usually prescribed at a fixed distance from the source axis by angiographic quantification of vessel diameter. Recently, intravascular ultrasound (IVUS) was introduced in dose prescription, allowing a better evaluation of the vessel anatomy. This study retrospectively explores the difference between prescription following angiographic vessel sizing and delivered dose calculated with IVUS. Methods and results: Seventeen lesions were studied with IVUS, identifying on irradiated segment, three sections on which measuring minimal and maximal distance from the centre of IVUS catheter to the adventitia; using dedicated software, corresponding doses were calculated. The dose ranged widely, with maximal and minimal values of 71.6 and 4.9 Gy; furthermore, heterogeneity in dose among different sections was observed. In the central section, the maximal dose was 206% of the one prescribed with the QCA model at 2 mm from the source axis, while the minimal dose was 96%. In proximal and distal sections, respective values were 182, 45, 243, and 122%. Conclusions: Our analysis confirmed the dose inhomogeneity delivered with an angiographic fixed-dose prescription strategy. A dose variation was found along the irradiated segment due to the differences in vessel thickness. IVUS emerged as an important tool in endovascular brachytherapy, especially for irregular-shaped vessels

  16. Association of insulin resistance and coronary artery remodeling: an intravascular ultrasound study

    OpenAIRE

    Kim, Sang-Hoon; Moon, Jae-Youn; Lim, Yeong Min; Kim, Kyung Ho; Yang, Woo-In; Sung, Jung-Hoon; Yoo, Seung Min; Kim, In Jai; Lim, Sang-Wook; Cha, Dong-Hun; Cho, Seung-Yun

    2015-01-01

    Background There are few studies that investigated the correlation between insulin resistance (IR) and the coronary artery remodeling. The aim of the study is to investigate the association of IR measured by homeostasis model assessment of insulin resistance (HOMA-IR) and coronary artery remodeling evaluated by intravascular ultrasound (IVUS). Methods A total of 298 consecutive patients who received percutaneous coronary interventions under IVUS guidance were retrospectively enrolled. The val...

  17. Application of intravascular ultrasound in percutaneous coronary interventional therapy

    International Nuclear Information System (INIS)

    Wang Jingping; Li Bao; An Jian; Yang Bin; Wang Zhongchao; Wang Rijun; Zhang Wutang; Lei Xinyu; Wang Huixian; Lu Lifang; Gao Yongli

    2009-01-01

    Objective: To evaluate intravascular ultrasound (IVUS)in demonstrating the characteristics of coronary plaque and in implanting the coronary stent. Methods: Before stent implantation, IVUS was used to observe the plaque character/sties(soft, fibrotic, calcified or mixed) as well as the eccentric degree in 28 patients with angiographically-proved single coronary branch lesion. The minimal luminal diameter, minimal cross-sectional area and plaque area were measured. After stent deployment the above measurements were repeated, and the location, symmetrical index and expansion of the stent were observed. Results: A total of 36 stents was implanted in 28 patients with coronary disease. After the procedure the minimal luminal diameter and the minimal cross-sectional area was increased, while the plaque area was decreased. The difference between the values before and after the stent implantation was statistically significant (P<0.01). IVUS after stent deployment found that in all cases the stent had a nice location and covered the lesion completely with no interlayer at its both ends. Excellent expansion of the stent was seen in 30 cases (83.3%). Insufficient expansion occurred in 3 cases and undesirable contact of the stent to the arterial wall was found in 3 cases (16.7%). In such circumstances, one size bigger low-compliance balloon dilatation was adopted, or the original balloon was used again with higher pressure (18-22 atm), in order to expand the stent once more, and good results accord with IVUS optimal criteria were obtained. Conclusions: IVUS can clearly demonstrate the pathological features of the coronary lesions, such as plaque type, eccentric degree, luminal diameter, cross-sectional area and plaque area, which are very helpful in guiding the selection of the proper stent before the procedure, and are also very useful in evaluating the location, expansion of the stent as well as the stent-to-wall contact condition after the procedure. (authors)

  18. Intravascular ultrasound assessed incomplete stent apposition and stent fracture in stent thrombosis after bare metal versus drug-eluting stent treatment the Nordic Intravascular Ultrasound Study (NIVUS)

    DEFF Research Database (Denmark)

    Kosonen, Petteri; Vikman, Saila; Jensen, Lisette Okkels

    2012-01-01

    This prospective multicenter registry used intravascular ultrasound (IVUS) in patients with definite stent thrombosis (ST) to compare rates of incomplete stent apposition (ISA), stent fracture and stent expansion in patients treated with drug-eluting (DES) versus bare metal (BMS) stents. ST...... is a rare, but potential life threatening event after coronary stent implantation. The etiology seems to be multifactorial....

  19. Intravascular ultrasound evaluation of a pseudolesion created by stent placement in the right artery.

    Science.gov (United States)

    Zientek, D M; Rodgers, G P

    1999-10-01

    The creation of a pseudolesion after guidewire placement in tortuous arterial segments is a well recognized phenomenon. Intravascular ultrasound has been useful in assessing deployment of intracoronary stents and equivocal angiographic findings. We present a case in which a pseudolesion was not observed until after placement of an intracoronary stent. Intravascular ultrasound demonstrated no dissection or significant lesion; however, there was focal calcification just distal to the stent providing a substrate for the distorted vessel architecture. The lesion resolved with removal of the guidewire.

  20. Design, construction, and validation of a rotary multifunctional intravascular diagnostic catheter combining multispectral fluorescence lifetime imaging and intravascular ultrasound.

    Science.gov (United States)

    Bec, Julien; Xie, Hongtao; Yankelevich, Diego R; Zhou, Feifei; Sun, Yang; Ghata, Narugopal; Aldredge, Ralph; Marcu, Laura

    2012-10-01

    We report the development and validation of an intravascular rotary catheter for bimodal interrogation of arterial pathologies. This is based on a point-spectroscopy scanning time-resolved fluorescence spectroscopy technique enabling reconstruction of fluorescence lifetime images (FLIm) and providing information on arterial intima composition and intravascular ultrasound (IVUS) providing information on arterial wall morphology. The catheter design allows for independent rotation of the ultrasonic and optical channels within an 8 Fr outer diameter catheter sheath and integrates a low volume flushing channel for blood removal in the optical pathways. In the current configuration, the two channels consist of (a) a standard 3 Fr IVUS catheter with single element transducer (40 MHz) and (b) a side-viewing fiber optic (400 μm core). Experiments conducted in tissue phantoms showed the ability of the catheter to operate in an intraluminal setting and to generate coregistered FLIm and IVUS in one pull-back scan. Current results demonstrate the feasibility of the catheter for simultaneous bimodal interrogation of arterial lumen and for generation of robust fluorescence lifetime data under IVUS guidance. These results facilitate further development of a FLIm-IVUS technique for intravascular diagnosis of atherosclerotic cardiovascular diseases including vulnerable plaques.

  1. Currently available methodologies for the processing of intravascular ultrasound and optical coherence tomography images.

    Science.gov (United States)

    Athanasiou, Lambros; Sakellarios, Antonis I; Bourantas, Christos V; Tsirka, Georgia; Siogkas, Panagiotis; Exarchos, Themis P; Naka, Katerina K; Michalis, Lampros K; Fotiadis, Dimitrios I

    2014-07-01

    Optical coherence tomography and intravascular ultrasound are the most widely used methodologies in clinical practice as they provide high resolution cross-sectional images that allow comprehensive visualization of the lumen and plaque morphology. Several methods have been developed in recent years to process the output of these imaging modalities, which allow fast, reliable and reproducible detection of the luminal borders and characterization of plaque composition. These methods have proven useful in the study of the atherosclerotic process as they have facilitated analysis of a vast amount of data. This review presents currently available intravascular ultrasound and optical coherence tomography processing methodologies for segmenting and characterizing the plaque area, highlighting their advantages and disadvantages, and discusses the future trends in intravascular imaging.

  2. Design of low noise transimpedance amplifier for intravascular ultrasound

    KAUST Repository

    Reda, Dina

    2009-11-01

    In this paper, we study transimpedance amplifiers for capacitive sensing applications with a focus on Intravascular Ultra Sound (IVUS). We employ RF noise cancellation technique on capacitive feedback based transimpedance amplifiers. This technique eliminates the input-referred noise of TIAs completely and enhances the dynamic range of front-end electronics. Simulation results verify the proposed technique used in two different TIA topologies employing shunt-shunt feedback. ©2009 IEEE.

  3. Transbiliary intravascular ultrasound-guided diagnostic biopsy of an inaccessible pancreatic head mass

    Directory of Open Access Journals (Sweden)

    Jeffrey Forris Beecham Chick, MD, MPH, DABR

    2017-06-01

    Full Text Available Percutaneous image-guided biopsies of pancreatic malignancies may prove challenging and nondiagnostic due to a variety of anatomic considerations. For patients with complex post-surgical anatomy, such as a Roux-en-Y gastric bypass, diagnosis via endoscopic ultrasound with fine-needle aspiration may not be possible because of an inability to reach the proximal duodenum. This report describes the first diagnostic case of transbiliary intravascular ultrasound-guided biopsy of a pancreatic head mass in a patient with prior Roux-en-Y gastric bypass for which a diagnosis could not be achieved via percutaneous and endoscopic approaches. Transbiliary intravascular ultrasound-guided biopsy resulted in a diagnosis of pancreatic adenocarcinoma, allowing the initiation of chemotherapy.

  4. Dose-volume histograms based on serial intravascular ultrasound: a calculation model for radioactive stents

    International Nuclear Information System (INIS)

    Kirisits, Christian; Wexberg, Paul; Gottsauner-Wolf, Michael; Pokrajac, Boris; Ortmann, Elisabeth; Aiginger, Hannes; Glogar, Dietmar; Poetter, Richard

    2001-01-01

    Background and purpose: Radioactive stents are under investigation for reduction of coronary restenosis. However, the actual dose delivered to specific parts of the coronary artery wall based on the individual vessel anatomy has not been determined so far. Dose-volume histograms (DVHs) permit an estimation of the actual dose absorbed by the target volume. We present a method to calculate DVHs based on intravascular ultrasound (IVUS) measurements to determine the dose distribution within the vessel wall. Materials and methods: Ten patients were studied by intravascular ultrasound after radioactive stenting (BX Stent, P-32, 15-mm length) to obtain tomographic cross-sections of the treated segments. We developed a computer algorithm using the actual dose distribution of the stent to calculate differential and cumulative DVHs. The minimal target dose, the mean target dose, the minimal doses delivered to 10 and 90% of the adventitia (DV10, DV90), and the percentage of volume receiving a reference dose at 0.5 mm from the stent surface cumulated over 28 days were derived from the DVH plots. Results were expressed as mean±SD. Results: The mean activity of the stents was 438±140 kBq at implantation. The mean reference dose was 111±35 Gy, whereas the calculated mean target dose within the adventitia along the stent was 68±20 Gy. On average, DV90 and DV10 were 33±9 Gy and 117±41 Gy, respectively. Expanding the target volume to include 2.5-mm-long segments at the proximal and distal ends of the stent, the calculated mean target dose decreased to 55±17 Gy, and DV 90 and DV 10 were 6.4±2.4 Gy and 107±36 Gy, respectively. Conclusions: The assessment of DVHs seems in principle to be a valuable tool for both prospective and retrospective analysis of dose-distribution of radioactive stents. It may provide the basis to adapt treatment planning in coronary brachytherapy to the common standards of radiotherapy

  5. Impact of peri-stent remodeling on restenosis: a volumetric intravascular ultrasound study.

    Science.gov (United States)

    Nakamura, M; Yock, P G; Bonneau, H N; Kitamura, K; Aizawa, T; Tamai, H; Fitzgerald, P J; Honda, Y

    2001-05-01

    Vessel remodeling is an important mechanism of late lumen loss after nonstent coronary interventions. However, its impact on in-stent restenosis has not been systematically investigated. Serial volumetric intravascular ultrasound analyses (poststent and follow-up) were performed in 55 lesions treated with a balloon-expandable stent (ACS MultiLink) using standard stent deployment techniques. The vessel volume (VV), lumen volume (LV), and volume bordered by the stent (SV) were measured using Simpson's method. The volume of plaque and neointima outside the stent (peri-stent volume, PSV) and volume of neointima within the stent (intrastent volume) were also measured. The change of each parameter during the follow-up period (follow-up minus poststent) was calculated and then divided by SV to normalize these values (designated as percent change [%]). As expected, %PSV directly correlated with %VV (Pexterior to a coronary stent occurs to a variable degree after stent implantation. There is a distinct trade-off between positive remodeling and in-stent hyperplasia: in segments in which the degree of peri-stent remodeling is less, intrastent neointimal proliferation is greater and accompanied by more significant late lumen loss.

  6. Development of an intravascular ultrasound elastography based on a dual-element transducer

    Science.gov (United States)

    Shih, Cho-Chiang; Chen, Pei-Yu; Ma, Teng; Zhou, Qifa; Shung, K. Kirk; Huang, Chih-Chung

    2018-04-01

    The ability to measure the elastic properties of plaques and vessels would be useful in clinical diagnoses, particularly for detecting a vulnerable plaque. This study demonstrates the feasibility of the combination of intravascular ultrasound (IVUS) and acoustic radiation force elasticity imaging for detecting the distribution of stiffness within atherosclerotic arteries ex vivo. A dual-frequency IVUS transducer with two elements was used to induce the propagation of the shear wave (by the 8.5 MHz pushing element) which could be simultaneously monitored by the 31 MHz imaging element. The wave-amplitude image and the wave-velocity image were reconstructed by measuring the peak displacement and wave velocity of shear wave propagation, respectively. System performance was verified using gelatin phantoms. The phantom results demonstrate that the stiffness differences of shear modulus of 1.6 kPa can be distinguished through the wave-amplitude and wave-velocity images. The stiffness distributions of the atherosclerotic aorta from a rabbit were obtained, for which the values of peak displacement and the shear wave velocity were 3.7 ± 1.2 µm and 0.38 ± 0.19 m s-1 for the lipid-rich plaques, and 1.0 ± 0.2 µm and 3.45 ± 0.45 m s-1 for the arterial walls, respectively. These results indicate that IVUS elasticity imaging can be used to distinguish the elastic properties of plaques and vessels.

  7. Offline fusion of co-registered intravascular ultrasound and frequency domain optical coherence tomography images for the analysis of human atherosclerotic plaques

    DEFF Research Database (Denmark)

    Räber, Lorenz; Heo, Jung Ho; Radu, Maria D

    2012-01-01

    To demonstrate the feasibility and potential usefulness of an offline fusion of matched optical coherence tomography (OCT) and intravascular ultrasound (IVUS)/virtual histology (IVUS-VH) images.......To demonstrate the feasibility and potential usefulness of an offline fusion of matched optical coherence tomography (OCT) and intravascular ultrasound (IVUS)/virtual histology (IVUS-VH) images....

  8. Reliability of mechanical and phased-array designs for serial intravascular ultrasound examinations--animal and clinical studies in stented and non-stented coronary arteries.

    Science.gov (United States)

    Tardif, J C; Bertrand, O F; Mongrain, R; Lespérance, J; Grégoire, J; Paiement, P; Bonan, R

    2000-10-01

    Both mechanical and multi-element intravascular ultrasound designs have potential advantages and limitations that may impact on their value for clinical and research purposes. Determination of the reproducibility of measurements is critical before a given system can be used in studies such as regression of atherosclerosis trials. We performed serial intravascular ultrasound imaging with catheters using mechanical and phased-array designs in stented and non-stented coronary arteries in dogs and in patients. Both systems correlated well for areas (r > or = 0.90, p or = 0.84. p mechanical designs for measurements of area (mean difference in dogs and in patients: -0.24 and 0.96 mm2, p mechanical system (r > or = 0.96 for all measurements). The differences in absolute and relative variability between the mechanical and phased-array designs, both for reanalysis of same frames and serial pullbacks, were very small. Although multi-element and mechanical intravascular ultrasound designs are not strictly interchangeable, their similar reproducibility and the small differences in measurements demonstrate that both designs are acceptable alternatives for trials of regression of atherosclerosis. Determination of the variability for serial pullbacks of both designs was also important to assess the statistical power of such trials.

  9. Improved automated lumen contour detection by novel multifrequency processing algorithm with current intravascular ultrasound system.

    Science.gov (United States)

    Kume, Teruyoshi; Kim, Byeong-Keuk; Waseda, Katsuhisa; Sathyanarayana, Shashidhar; Li, Wenguang; Teo, Tat-Jin; Yock, Paul G; Fitzgerald, Peter J; Honda, Yasuhiro

    2013-02-01

    The aim of this study was to evaluate a new fully automated lumen border tracing system based on a novel multifrequency processing algorithm. We developed the multifrequency processing method to enhance arterial lumen detection by exploiting the differential scattering characteristics of blood and arterial tissue. The implementation of the method can be integrated into current intravascular ultrasound (IVUS) hardware. This study was performed in vivo with conventional 40-MHz IVUS catheters (Atlantis SR Pro™, Boston Scientific Corp, Natick, MA) in 43 clinical patients with coronary artery disease. A total of 522 frames were randomly selected, and lumen areas were measured after automatically tracing lumen borders with the new tracing system and a commercially available tracing system (TraceAssist™) referred to as the "conventional tracing system." The data assessed by the two automated systems were compared with the results of manual tracings by experienced IVUS analysts. New automated lumen measurements showed better agreement with manual lumen area tracings compared with those of the conventional tracing system (correlation coefficient: 0.819 vs. 0.509). When compared against manual tracings, the new algorithm also demonstrated improved systematic error (mean difference: 0.13 vs. -1.02 mm(2) ) and random variability (standard deviation of difference: 2.21 vs. 4.02 mm(2) ) compared with the conventional tracing system. This preliminary study showed that the novel fully automated tracing system based on the multifrequency processing algorithm can provide more accurate lumen border detection than current automated tracing systems and thus, offer a more reliable quantitative evaluation of lumen geometry. Copyright © 2011 Wiley Periodicals, Inc.

  10. Determination of Stent Stenosis: An In Vivo Experimental Comparison of Intravascular Ultrasound and Angiography with Histology

    International Nuclear Information System (INIS)

    Schuermann, Karl; Vorwerk, Dierk; Uppenkamp, Robert; Klosterhalfen, Bernd; Buecker, Arno; Guenther, Rolf W.

    1998-01-01

    Purpose: To compare intravascular ultrasound (IVUS) and angiography with histology in determining the degree of stent stenosis in an in vivo experiment. Methods: In 16 sheep, a total of 64 stents were implanted into the external iliac arteries. Two stents were inserted on either side. Patency was followed by angiography and IVUS. Four types of stent were used: two Dacron-covered (Cragg Endopro and heparinized Cragg Endopro) and two non-covered (Cragg and Memotherm stents). Eight animals were killed after 1 month, eight others after 6 months. Histological sections were prepared from the stented vessels. Measurements of the patent and total stent diameters determined by IVUS, angiography, and histology were compared. Results: Correlation between IVUS and angiography was 0.75, between IVUS and histology 0.77, and between angiography and histology 0.85. A mean stent stenosis of 17 ± 11% (range 0-51%) was found on angiography, of 10 ± 11% (0-46%) on IVUS, and of 20 ± 11% (4%-49%) on histology. In comparison with histology, IVUS underestimated the degree of stenosis by 10 ± 8%, and angiography underestimated it by 3 ± 6%. Resolution of IVUS was calculated to be about 0.35 mm and that of angiography to be about 0.15 mm. Conclusion: Under experimental conditions, IVUS was not superior to angiography in determining the degree of stent stenosis in long-segment stenoses of iliac artery stents, when measurements were correlated with histology. Angiography is sufficient for following the patency of iliac artery stents

  11. Abnormal pulmonary artery stiffness in pulmonary arterial hypertension: in vivo study with intravascular ultrasound.

    Directory of Open Access Journals (Sweden)

    Edmund M T Lau

    Full Text Available BACKGROUND: There is increasing recognition that pulmonary artery stiffness is an important determinant of right ventricular (RV afterload in pulmonary arterial hypertension (PAH. We used intravascular ultrasound (IVUS to evaluate the mechanical properties of the elastic pulmonary arteries (PA in subjects with PAH, and assessed the effects of PAH-specific therapy on indices of arterial stiffness. METHOD: Using IVUS and simultaneous right heart catheterisation, 20 pulmonary segments in 8 PAH subjects and 12 pulmonary segments in 8 controls were studied to determine their compliance, distensibility, elastic modulus and stiffness index β. PAH subjects underwent repeat IVUS examinations after 6-months of bosentan therapy. RESULTS: AT BASELINE, PAH SUBJECTS DEMONSTRATED GREATER STIFFNESS IN ALL MEASURED INDICES COMPARED TO CONTROLS: compliance (1.50±0.11×10(-2 mm(2/mmHg vs 4.49±0.43×10(-2 mm(2/mmHg, p<0.0001, distensibility (0.32±0.03%/mmHg vs 1.18±0.13%/mmHg, p<0.0001, elastic modulus (720±64 mmHg vs 198±19 mmHg, p<0.0001, and stiffness index β (15.0±1.4 vs 11.0±0.7, p = 0.046. Strong inverse exponential associations existed between mean pulmonary artery pressure and compliance (r(2 = 0.82, p<0.0001, and also between mean PAP and distensibility (r(2 = 0.79, p = 0.002. Bosentan therapy, for 6-months, was not associated with any significant changes in all indices of PA stiffness. CONCLUSION: Increased stiffness occurs in the proximal elastic PA in patients with PAH and contributes to the pathogenesis RV failure. Bosentan therapy may not be effective at improving PA stiffness.

  12. Intravascular ultrasound assessment of minimumlumen area and intimal hyperplasia in in-stent restenosis after drug-eluting or bare-metal stent implantation. The Nordic Intravascular Ultrasound Study (NIVUS)

    DEFF Research Database (Denmark)

    Jensen, Lisette Okkels; Vikman, Saila; Antonsen, Lisbeth

    2017-01-01

    presenting with a DES or bare-metal stent (BMS) in-stent restenosis. Methods: The ``Nordic Intravascular Ultrasound Study (NIVUS)'' study was conducted in Nordic and Baltic countries as a prospective multicenter registry. Two hundred nine patients (DES n = 121 and BMS n = 88) with instent restenosis were...

  13. Intravascular Ultrasound

    Science.gov (United States)

    ... Rounds Seminar Series & Daily Conferences Fellowships and Residencies School of Perfusion Technology Education Resources Library & Learning Resource Center CME Resources THI Journal THI Cardiac Society Register for the Cardiac Society ...

  14. Comparison of intravascular ultrasound and angiographic assessement of coronary reference segment size in patients with type 2 diabetes mellitus

    DEFF Research Database (Denmark)

    Jensen, Lisette Okkels; Thayssen, Per; Mintz, Gary S

    2008-01-01

    During percutaneous coronary intervention, the reference segment is assessed angiographically. This report described the discrepancy between angiographic and intravascular ultrasound (IVUS) assessment of reference segment size in patients with type 2 diabetes mellitus. Preintervention IVUS was used...... to study 62 de novo lesions in 41 patients with type 2 diabetes mellitus. The lesion site was the image slice with the smallest lumen cross-sectional area (CSA). The proximal and distal reference segments were the most normal-looking segments within 5 mm proximal and distal to the lesion. Plaque burden...... was measured as plaque CSA/external elastic membrane (EEM) CSA. Using IVUS, the reference lumen diameter was 2.80 +/- 0.42 mm and the reference EEM diameter was 4.17 +/- 0.56 mm. The angiographic reference diameter was 2.63 +/- 0.36 mm. Mean difference between the IVUS EEM diameter and angiographic reference...

  15. Focus on the research utility of intravascular ultrasound - comparison with other invasive modalities

    Directory of Open Access Journals (Sweden)

    Hoye Angela

    2011-01-01

    Full Text Available Abstract Intravascular ultrasound (IVUS is an invasive modality which provides cross-sectional images of a coronary artery. In these images both the lumen and outer vessel wall can be identified and accurate estimations of their dimensions and of the plaque burden can be obtained. In addition, further processing of the IVUS backscatter signal helps in the characterization of the type of the plaque and thus it has been used to study the natural history of the atherosclerotic evolution. On the other hand its indigenous limitations do not allow IVUS to assess accurately stent struts coverage, existence of thrombus or exact site of plaque rupture and to identify some of the features associated with increased plaque vulnerability. In order this information to be obtained, other modalities such as optical coherence tomography, angioscopy, near infrared spectroscopy and intravascular magnetic resonance imaging have either been utilized or are under evaluation. The aim of this review article is to present the current utilities of IVUS in research and to discuss its advantages and disadvantages over the other imaging techniques.

  16. A state-of-the-art review on segmentation algorithms in intravascular ultrasound (IVUS) images.

    Science.gov (United States)

    Katouzian, Amin; Angelini, Elsa D; Carlier, Stéphane G; Suri, Jasjit S; Navab, Nassir; Laine, Andrew F

    2012-09-01

    Over the past two decades, intravascular ultrasound (IVUS) image segmentation has remained a challenge for researchers while the use of this imaging modality is rapidly growing in catheterization procedures and in research studies. IVUS provides cross-sectional grayscale images of the arterial wall and the extent of atherosclerotic plaques with high spatial resolution in real time. In this paper, we review recently developed image processing methods for the detection of media-adventitia and luminal borders in IVUS images acquired with different transducers operating at frequencies ranging from 20 to 45 MHz. We discuss methodological challenges, lack of diversity in reported datasets, and weaknesses of quantification metrics that make IVUS segmentation still an open problem despite all efforts. In conclusion, we call for a common reference database, validation metrics, and ground-truth definition with which new and existing algorithms could be benchmarked.

  17. Intravascular ultrasound assessment of remodelling and reference segment plaque burden in type-2 diabetic patients

    DEFF Research Database (Denmark)

    Jensen, Lisette Okkels; Thayssen, Per; Mintz, Gary S

    2007-01-01

    AIMS: Intravascular ultrasound (IVUS) assesses arterial remodelling by comparing the lesion external elastic membrane (EEM) with the reference segments; however, reference segments are rarely disease-free. The aim was to assess lesion and reference segment remodelling and plaque burden in patients...... with type-2 diabetes mellitus. METHODS AND RESULTS: We used pre-intervention IVUS to study 62 de novo lesions in 43 patients with type-2 diabetes mellitus. The lesion site was the image slice with the smallest lumen cross-sectional area (CSA). The proximal and distal reference segments were the most normal...... size [slope = -0.12 (95% CI -0.17 to -0.07); P type-2 diabetes mellitus. CONCLUSION: Lesions in type-2 diabetic patients are different from previous reports in non-diabetics. Lesions in type-2 diabetics are characterized by a large reference segment plaque burden...

  18. An automated approach for segmentation of intravascular ultrasound images based on parametric active contour models

    International Nuclear Information System (INIS)

    Vard, Alireza; Jamshidi, Kamal; Movahhedinia, Naser

    2012-01-01

    This paper presents a fully automated approach to detect the intima and media-adventitia borders in intravascular ultrasound images based on parametric active contour models. To detect the intima border, we compute a new image feature applying a combination of short-term autocorrelations calculated for the contour pixels. These feature values are employed to define an energy function of the active contour called normalized cumulative short-term autocorrelation. Exploiting this energy function, the intima border is separated accurately from the blood region contaminated by high speckle noise. To extract media-adventitia boundary, we define a new form of energy function based on edge, texture and spring forces for the active contour. Utilizing this active contour, the media-adventitia border is identified correctly even in presence of branch openings and calcifications. Experimental results indicate accuracy of the proposed methods. In addition, statistical analysis demonstrates high conformity between manual tracing and the results obtained by the proposed approaches.

  19. Comparison of angiography and intravascular ultrasound before and after balloon angioplasty of the femoropopliteal artery

    International Nuclear Information System (INIS)

    Lankeren, Winnifred van; Gussenhoven, Elma J.; Pieterman, Herman; Sambeek, Marc R. H. M. van; Lugt, Aad van der

    1998-01-01

    Purpose: To compare angiographic and intravascular ultrasound (IVUS) data before and after balloon angioplasty (PTA) of the femoropopliteal artery.Methods: Qualitative and quantitative analyses were performed on corresponding angiographic and IVUS levels obtained from 135 patients.Results: IVUS detected more lesions, calcified lesions, and vascular damage than angiography. Sensitivity of angiography was good for the presence of a lesion (84%), moderate for eccentric lesions (53%) and for vascular damage (52%), and poor for calcified lesions (30%). The increase in angiographic diameter stenosis was associated with a decrease in lumen area and increase in percentage area stenosis on IVUS.Conclusions: Angiography is less sensitive than IVUS for detecting lesion eccentricity, calcified lesions, and vascular damage. Presence of a lesion and amount of plaque were underestimated angiographically. Only before PTA was good agreement found between angiographic diameter stenosis and lumen size on IVUS.

  20. Perspectives on Imaging the Left Main Coronary Artery Using Intravascular Ultrasound and Optical Coherence Tomography

    Directory of Open Access Journals (Sweden)

    Harry C Lowe

    2015-01-01

    Full Text Available Percutaneous Coronary Intervention (PCI for significant left main coronary artery (LMCA stenosis is increasingly being viewed as a viable alternative to Coronary Artery Bypass Grafting (CABG (1. This is leading to an expectation of increasing numbers of such procedures, with a consequent focus on both the ability to image both lesion severity, and assess more accurately the results of PCI. While there have been advances in physiologic assessment of left main severity using fractional flow reserve (FFR, imaging of the LMCA using Intravascular Ultrasound (IVUS and more recently Optical Coherence Tomography (OCT has the specific advantage of being able to provide detailed anatomical information both pre and post PCI, such that it is timely to review briefly the current status of these two imaging technologies in the context of LMCA intervention.

  1. Intravascular forward-looking ultrasound transducers for microbubble-mediated sonothrombolysis.

    Science.gov (United States)

    Kim, Jinwook; Lindsey, Brooks D; Chang, Wei-Yi; Dai, Xuming; Stavas, Joseph M; Dayton, Paul A; Jiang, Xiaoning

    2017-06-14

    Effective removal or dissolution of large blood clots remains a challenge in clinical treatment of acute thrombo-occlusive diseases. Here we report the development of an intravascular microbubble-mediated sonothrombolysis device for improving thrombolytic rate and thus minimizing the required dose of thrombolytic drugs. We hypothesize that a sub-megahertz, forward-looking ultrasound transducer with an integrated microbubble injection tube is more advantageous for efficient thrombolysis by enhancing cavitation-induced microstreaming than the conventional high-frequency, side-looking, catheter-mounted transducers. We developed custom miniaturized transducers and demonstrated that these transducers are able to generate sufficient pressure to induce cavitation of lipid-shelled microbubble contrast agents. Our technology demonstrates a thrombolysis rate of 0.7 ± 0.15 percent mass loss/min in vitro without any use of thrombolytic drugs.

  2. Orbital Atherectomy Plaque Modification Assessment of the Femoropopliteal Artery Via Intravascular Ultrasound (TRUTH Study).

    Science.gov (United States)

    Babaev, Anvar; Zavlunova, Susanna; Attubato, Michael J; Martinsen, Brad J; Mintz, Gary S; Maehara, Akiko

    2015-10-01

    The Tissue Removal Assessment with Ultrasound of the SFA and Popliteal (TRUTH) study assessed the performance of the orbital atherectomy system (OAS) to treat femoropopliteal arteries, including determining its effect on plaque removal. Patients with symptomatic femoropopliteal peripheral arterial disease were treated with the OAS followed by adjunctive balloon angioplasty (BA). Intravascular ultrasound (IVUS) images were collected pre- and post-OAS and post-OAS BA. Patients were followed through 12 months post-procedure. Twenty-nine lesions were treated with OAS-BA in 25 patients. The mean maximum balloon inflation pressure was 5.2 ± 1.2 atm. Virtual histology IVUS (VH-IVUS) analysis revealed at the maximum calcium ablation site that calcium reduction was responsible for 86% of the lumen area increase. The minimum lumen area increased from 4.0 mm(2) to 9.1 mm(2) (<.0001), and the percentage of area stenosis decreased from 76.9% to 43.0% (<.0001) after OAS-BA. At 12 months, the target lesion revascularization rate was 8.2%, and ankle-brachial index and Rutherford classification improved significantly from baseline through follow-up. The VH-IVUS analysis reveals that OAS modifies the calcified component of the plaque burden. It is hypothesized that calcium modification by OAS changes the lesion compliance, allowing for low pressure adjunctive BA. The clinical outcomes were favorable through 12-month follow-up. © The Author(s) 2015.

  3. Head to head comparison of optical coherence tomography, intravascular ultrasound echogenicity and virtual histology for the detection of changes in polymeric struts over time

    DEFF Research Database (Denmark)

    Brugaletta, Salvatore; Gomez-Lara, Josep; Bruining, Nico

    2012-01-01

    To analyse and to compare the changes in the various optical coherence tomography (OCT), echogenicity and intravascular ultrasound virtual histology (VH) of the everolimus-eluting bioresorbable scaffold (ABSORB) degradation parameters during the first 12 months after ABSORB implantation. In the A......To analyse and to compare the changes in the various optical coherence tomography (OCT), echogenicity and intravascular ultrasound virtual histology (VH) of the everolimus-eluting bioresorbable scaffold (ABSORB) degradation parameters during the first 12 months after ABSORB implantation...

  4. Lumen and calcium characteristics within calcified coronary lesions. Comparison of computed tomography coronary angiography versus intravascular ultrasound

    OpenAIRE

    Noll, Dariusz; Kruk, Mariusz; Pręgowski, Jerzy; Kaczmarska, Edyta; Kryczka, Karolina; Pracoń, Radosław; Skwarek, Mirosław; Dzielińska, Zofia; Petryka, Joanna; Śpiewak, Mateusz; Lubiszewska, Barbara; Norwa-Otto, Bożena; Opolski, Maksymilian; Witkowski, Adam; Demkow, Marcin

    2013-01-01

    Introduction Computed tomography coronary angiography (CTCA) is a diagnostic method used for exclusion of coronary artery disease. However, lower accuracy of CTCA in assessment of calcified lesions is a significant factor impeding applicability of CTCA for assessment of coronary atherosclerosis. Aim To provide insight into lumen and calcium characteristics assessed with CTCA, we compared these parameters to the reference of intravascular ultrasound (IVUS). Material and methods Two hundred and...

  5. The Precise Determination of Vascular Lumen and Stent Diameters: Correlation Among Calibrated Angiography, Intravascular Ultrasound, and Pressure-Fixed Specimens

    International Nuclear Information System (INIS)

    Froelich, Jens J.; Hoppe, Martin; Nahrstedt, Christoph; Barth, Klemens H.; Wagner, H. Joachim; Klose, Klaus J.

    1997-01-01

    Purpose: Luminal diameters measured in vivo by calibrated-catheter angiography and by intravascular ultrasound were correlated with those obtained from pressure-fixed histologic cross-sections to determine the accuracy of both methods. Methods: Angiographic and endosonographic diameter measurements were performed in the center of stents placed in the iliac arteries of 10 miniature pigs and were compared with luminal and stent diameters in postmortem, pressure-fixed, histologic cross-sections from identical locations. Results: Compared with histologic diameters, magnification-corrected angiographic measurements still magnified vascular luminal diameters by 0.7 ± 0.71 mm (r= 0.41, Pearson; p 0.5, Wilcoxon, matched pairs). Similarly, stent diameters correlated well between endosonographic and histologic measurements (r= 0.91; p= 0.002), and less well between angiographic and histologic diameters (r= 0.62; p= 0.002). Conclusion: Since calibrated angiography still overestimates vascular lumina, endosonography is the preferred technique for accurate in vivo measurements

  6. Angiographically borderline left main coronary artery lesions: correlation of transthoracic doppler echocardiography and intravascular ultrasound: a pilot study

    Directory of Open Access Journals (Sweden)

    Varga Albert

    2011-06-01

    Full Text Available Abstract Background the clinical decision making could be difficult in patients with borderline lesions (visually assessed stenosis severity of 30 to 50% of the left main coronary artery (LM. The aim of the study was to evaluate the relationship between transthoracic Doppler (TTDE peak diastolic flow velocity (PDV and intravascular ultrasound (IVUS measurements in the assessment of angiographically borderline LM lesions. Methods 27 patients (mean age 64 ± 8 years, 21 males with borderline LM stenosis referred for IVUS examination were included in the study. We performed standard IVUS with minimal lumen area (MLA and plaque burden (PB measurement and routine quantitative coronary angiography (QCA with diameter stenosis (%DS and area stenosis (%AS assessment in all. During TTDE, resting PDV was measured in the LM. Results interpretable Doppler signal could be obtained in 24 patients (88% feasibility; therefore these patients entered the final analysis. MLA was 7.1 ± 2.7 mm2. TTDE measured PDV correlated significantly with IVUS-derived MLA (r = -0.46, p 2 LM stenosis. Conclusion In angiographically borderline LM disease, resting PDV from transthoracic echocardiography is increased in presence of increased plaque burden by IVUS. TTDE evaluation might be a useful adjunct to other invasive and non-invasive methods in the assessment of borderline LM lesions. Further, large scale studies are needed to establish the exact cut-off value of PDV for routine clinical application.

  7. TWO NOVEL ACM (ACTIVE CONTOUR MODEL) METHODS FOR INTRAVASCULAR ULTRASOUND IMAGE SEGMENTATION

    International Nuclear Information System (INIS)

    Chen, Chi Hau; Potdat, Labhesh; Chittineni, Rakesh

    2010-01-01

    One of the attractive image segmentation methods is the Active Contour Model (ACM) which has been widely used in medical imaging as it always produces sub-regions with continuous boundaries. Intravascular ultrasound (IVUS) is a catheter based medical imaging technique which is used for quantitative assessment of atherosclerotic disease. Two methods of ACM realizations are presented in this paper. The gradient descent flow based on minimizing energy functional can be used for segmentation of IVUS images. However this local operation alone may not be adequate to work with the complex IVUS images. The first method presented consists of basically combining the local geodesic active contours and global region-based active contours. The advantage of combining the local and global operations is to allow curves deforming under the energy to find only significant local minima and delineate object borders despite noise, poor edge information and heterogeneous intensity profiles. Results for this algorithm are compared to standard techniques to demonstrate the method's robustness and accuracy. In the second method, the energy function is appropriately modified and minimized using a Hopfield neural network. Proper modifications in the definition of the bias of the neurons have been introduced to incorporate image characteristics. The method overcomes distortions in the expected image pattern, such as due to the presence of calcium, and employs a specialized structure of the neural network and boundary correction schemes which are based on a priori knowledge about the vessel geometry. The presented method is very fast and has been evaluated using sequences of IVUS frames.

  8. Angioplasty Guided by Intravascular Ultrasound: Meta-Analysis of Randomized Clinical Trials

    Energy Technology Data Exchange (ETDEWEB)

    Figueiredo, José Albuquerque Neto de, E-mail: jafneto@cardiol.br; Nogueira, Iara Antonia Lustosa [Universidade Federal do Maranhão, São Luiz, MA (Brazil); Figueiro, Mabel Fernandes; Buehler, Anna Maria; Berwanger, Otavio [Instituto de Ensino e Pesquisa do Hospital do Coração, São Paulo, SP (Brazil)

    2013-08-15

    The impact of intravascular ultrasound (IVUS) use on stenting has shown inconclusive results. Systematic review and meta-analysis of the impact of IVUS on stenting regarding the clinical and angiographic evolution. A search was performed in Medline/Pubmed, CENTRAL, Embase, Lilacs, Scopus and Web of Science databases. It included randomized clinical trials (RCTs) that evaluated the implantation of stents guided by IVUS, compared with those using angiography alone (ANGIO). The minimum follow-up duration was six months and the following outcomes were assessed: thrombosis, mortality, myocardial infarction, percutaneous and surgical revascularization, major adverse cardiovascular events (MACE) and restenosis. The binary outcomes were presented considering the number of events in each group; the estimates were generated by a random effects model, considering Mantel-Haenszel statistics as weighting agent and magnitude of effect for the relative risk (RR) with its respective 95% confidence interval (95%CI). Higgins I{sup 2} test was used to quantify the consistency between the results of each study. A total of 2,689 articles were evaluated, including 8 RCTs. There was a 27% reduction in angiographic restenosis (RR: 0.73, 95% CI: 0.54-0.97, I{sup 2} = 51%) and statistically significant reduction in the rates of percutaneous revascularization and overall (RR: 0.88; 95% CI: 0.51 to 1.53, I{sup 2} = 61%, RR: 0.73, 95% CI: 0.54 to 0.99, I{sup 2} = 55%), with no statistical difference in surgical revascularization (RR: 0.95, 95% CI: 0.52-1.74, I{sup 2} = 0%) in favor of IVUS vs. ANGIO. There were no differences regarding the other outcomes in the comparison between the two strategies. Angioplasty with stenting guided by IVUS decreases the rates of restenosis and revascularization, with no impact on MACE, acute myocardial infarction, mortality or thrombosis outcomes.

  9. Intravascular ultrasound evaluation of JETSTREAM atherectomy removal of superficial calcium in peripheral arteries.

    Science.gov (United States)

    Maehara, Akiko; Mintz, Gary S; Shimshak, Thomas M; Ricotta, Joseph J; Ramaiah, Venkatesh; Foster, Malcolm T; Davis, Thomas P; Gray, William A

    2015-05-01

    Endovascular treatment of calcified femoral-popliteal disease is challenging. We sought to evaluate the mechanism of lumen gain when using the JETSTREAM Atherectomy System to treat calcified peripheral artery lesions. The JETSTREAM Calcium Study was a prospective, single-arm, multicentre study to evaluate the JETSTREAM Atherectomy System for severely calcified femoral-popliteal artery lesions, i.e., patients with claudication and lesions with superficial calcium >90° and >5 mm in length as determined by intravascular ultrasound (IVUS). The 2.1 mm catheter was used in this study without distal protection. Fifty-five patients underwent angiographic screening: 26 (45%) met IVUS inclusion criteria. Angiographic calcium was moderate in eight cases and severe in 14, with no available data for four cases. Visual diameter stenosis was 86±9% pre-treatment, 37±13% post atherectomy, and 10±6% post adjunctive treatment (adjunctive PTA+stenting in eight and adjunct PTA alone in 16). IVUS showed lumen area increased from 6.6±3.7 mm2 to 10.0±3.6 mm2 (p=0.001): calcium reduction was responsible for 86±23% of the lumen increase. Although the superficial calcium arc did not change (151±70° to 146±71°, p=0.83), the arc of reverberation increased (23±20° to 65±40°, p=0.006), indicating device-related modification of calcium. Adjunctive balloon angioplasty was performed in 62% of the lesions, and stent implantation in 31%. In 11 cases with adjunctive balloon dilation, the MLA increased from 7.1 (6.4, 7.8) mm2 post atherectomy to 11.9 (10.3, 13.5) mm2 post balloon (pAtherectomy System increased lumen dimensions in moderately or severely calcified femoral-popliteal lesions by removing superficial calcium without major complications.

  10. Multidimensional segmentation of coronary intravascular ultrasound images using knowledge-based methods

    Science.gov (United States)

    Olszewski, Mark E.; Wahle, Andreas; Vigmostad, Sarah C.; Sonka, Milan

    2005-04-01

    In vivo studies of the relationships that exist among vascular geometry, plaque morphology, and hemodynamics have recently been made possible through the development of a system that accurately reconstructs coronary arteries imaged by x-ray angiography and intravascular ultrasound (IVUS) in three dimensions. Currently, the bottleneck of the system is the segmentation of the IVUS images. It is well known that IVUS images contain numerous artifacts from various sources. Previous attempts to create automated IVUS segmentation systems have suffered from either a cost function that does not include enough information, or from a non-optimal segmentation algorithm. The approach presented in this paper seeks to strengthen both of those weaknesses -- first by building a robust, knowledge-based cost function, and then by using a fully optimal, three-dimensional segmentation algorithm. The cost function contains three categories of information: a compendium of learned border patterns, information theoretic and statistical properties related to the imaging physics, and local image features. By combining these criteria in an optimal way, weaknesses associated with cost functions that only try to optimize a single criterion are minimized. This cost function is then used as the input to a fully optimal, three-dimensional, graph search-based segmentation algorithm. The resulting system has been validated against a set of manually traced IVUS image sets. Results did not show any bias, with a mean unsigned luminal border positioning error of 0.180 +/- 0.027 mm and an adventitial border positioning error of 0.200 +/- 0.069 mm.

  11. Automatic segmentation and 3D reconstruction of intravascular ultrasound images for a fast preliminar evaluation of vessel pathologies.

    Science.gov (United States)

    Sanz-Requena, Roberto; Moratal, David; García-Sánchez, Diego Ramón; Bodí, Vicente; Rieta, José Joaquín; Sanchis, Juan Manuel

    2007-03-01

    Intravascular ultrasound (IVUS) imaging is used along with X-ray coronary angiography to detect vessel pathologies. Manual analysis of IVUS images is slow and time-consuming and it is not feasible for clinical purposes. A semi-automated method is proposed to generate 3D reconstructions from IVUS video sequences, so that a fast diagnose can be easily done, quantifying plaque length and severity as well as plaque volume of the vessels under study. The methodology described in this work has four steps: a pre-processing of IVUS images, a segmentation of media-adventitia contour, a detection of intima and plaque and a 3D reconstruction of the vessel. Preprocessing is intended to remove noise from the images without blurring the edges. Segmentation of media-adventitia contour is achieved using active contours (snakes). In particular, we use the gradient vector flow (GVF) as external force for the snakes. The detection of lumen border is obtained taking into account gray-level information of the inner part of the previously detected contours. A knowledge-based approach is used to determine which level of gray corresponds statistically to the different regions of interest: intima, plaque and lumen. The catheter region is automatically discarded. An estimate of plaque type is also given. Finally, 3D reconstruction of all detected regions is made. The suitability of this methodology has been verified for the analysis and visualization of plaque length, stenosis severity, automatic detection of the most problematic regions, calculus of plaque volumes and a preliminary estimation of plaque type obtaining for automatic measures of lumen and vessel area an average error smaller than 1mm(2) (equivalent aproximately to 10% of the average measure), for calculus of plaque and lumen volume errors smaller than 0.5mm(3) (equivalent approximately to 20% of the average measure) and for plaque type estimates a mismatch of less than 8% in the analysed frames.

  12. Renal Sympathetic Denervation System via Intraluminal Ultrasonic Ablation: Therapeutic Intravascular Ultrasound Design and Preclinical Evaluation.

    Science.gov (United States)

    Chernin, Gil; Szwarcfiter, Iris; Bausback, Yvonne; Jonas, Michael

    2017-05-01

    To assess the safety and performance of a nonfocused and nonballooned ultrasonic (US) catheter-based renal sympathetic denervation (RDN) system in normotensive swine. RDN with the therapeutic intravascular US catheter was evaluated in 3 experiments: (i) therapeutic intravascular US RDN vs a control group of untreated animals with follow-up of 30, 45, and 90 days (n = 6; n = 12 renal arteries for each group); (ii) therapeutic intravascular US RDN vs radiofrequency (RF) RDN in the contralateral artery in the same animal (n = 2; n = 4 renal arteries); and (iii) therapeutic intravascular US RDN in a recently stent-implanted renal artery (n = 2; n = 4 renal arteries). In the first experiment, therapeutic intravascular US RDN was safe, without angiographic evidence of dissection or renal artery stenosis. Neuronal tissue vacuolization, nuclei pyknosis, and perineuronal inflammation were evident after RDN, without renal artery wall damage. Norepinephrine levels were significantly lower after therapeutic intravascular US RDN after 30, 45, and 90 days compared with the control group (200.17 pg/mg ± 63.35, 184.75 pg/mg ± 44.51, and 203.43 pg/mg ± 58.54, respectively, vs 342.42 pg/mg ± 79.97). In the second experiment, deeper neuronal ablation penetrance was found with therapeutic intravascular US RDN vs RF RDN (maximal penetrance from endothelium of 7.0 mm vs 3.5 mm, respectively). There was less damage to the artery wall after therapeutic intravascular US RDN than with RF RDN, after which edema and injured endothelium were seen. In the third experiment, denervation inside the stent-implanted segments was feasible without damage to the renal artery wall or stent. The therapeutic intravascular US system performed safely and reduced norepinephrine levels. Deeper penetrance and better preservation of vessel wall were observed with therapeutic intravascular US RDN vs RF RDN. Neuronal ablations were observed in stent-implanted renal arteries. Copyright © 2017 SIR. Published

  13. Lumen and calcium characteristics within calcified coronary lesions. Comparison of computed tomography coronary angiography versus intravascular ultrasound.

    Science.gov (United States)

    Noll, Dariusz; Kruk, Mariusz; Pręgowski, Jerzy; Kaczmarska, Edyta; Kryczka, Karolina; Pracoń, Radosław; Skwarek, Mirosław; Dzielińska, Zofia; Petryka, Joanna; Spiewak, Mateusz; Lubiszewska, Barbara; Norwa-Otto, Bożena; Opolski, Maksymilian; Witkowski, Adam; Demkow, Marcin; Rużyłło, Witold; Kępka, Cezary

    2013-01-01

    Computed tomography coronary angiography (CTCA) is a diagnostic method used for exclusion of coronary artery disease. However, lower accuracy of CTCA in assessment of calcified lesions is a significant factor impeding applicability of CTCA for assessment of coronary atherosclerosis. To provide insight into lumen and calcium characteristics assessed with CTCA, we compared these parameters to the reference of intravascular ultrasound (IVUS). Two hundred and fifty-two calcified lesions within 97 arteries of 60 patients (19 women, age 63 ±10 years) underwent assessment with both 2 × 64 slice CT (Somatom Definition, Siemens) and IVUS (s5, Volcano Corp.). Coronary lumen and calcium dimensions within calcified lesions were assessed with CTCA and compared to the reference measurements made with IVUS. On average CTCA underestimated mean lumen diameter (2.8 ±0.7 mm vs. 2.9 ±0.8 mm for IVUS), lumen area (6.4 ±3.4 mm(2) vs. 7.0 ±3.7 mm(2) for IVUS, p < 0.001) and total calcium arc (52 ±35° vs. 83 ±54°). However, analysis of tertiles of the examined parameters revealed that the mean lumen diameter, lumen area and calcium arc did not significantly differ between CTCA and IVUS within the smallest lumens (1(st) tertile of mean lumen diameter at 2.1 mm, and 1(st) tertile of lumen area at 3.7 mm(2)) and lowest calcium arc (mean of 40°). Although, on average, CTCA underestimates lumen diameter and area as well as calcium arc within calcified lesions, the differences are not significant within the smallest vessels and calcium arcs. The low diagnostic accuracy of CTCA within calcified lesions may be attributed to high variance and not to systematic error of measurements.

  14. Optical Coherence Tomography Analysis of Attenuated Plaques Detected by Intravascular Ultrasound in Patients with Acute Coronary Syndromes

    Directory of Open Access Journals (Sweden)

    Takashi Kubo

    2011-01-01

    Full Text Available Background. Recent intravascular ultrasound (IVUS studies have demonstrated that hypoechoic plaque with deep ultrasound attenuation despite absence of bright calcium is common in acute coronary syndrome. Such “attenuated plaque” may be an IVUS characteristic of unstable lesion. Methods. We used optical coherence tomography (OCT in 104 patients with unstable angina to compare lesion characteristics between IVUS-detected attenuated plaque and nonattenuated plaque. Results. IVUS-detected attenuated plaque was observed in 41 (39% patients. OCT-detected lipidic plaque (88% versus 49%, <0.001, thin-cap fibroatheroma (48% versus 16%, <0.001, plaque rupture (44% versus 11%, <0.001, and intracoronary thrombus (54% versus 17%, <0.001 were more often seen in IVUS-detected attenuated plaques compared with nonattenuated plaques. Conclusions. IVUS-detected attenuated plaque has many characteristics of unstable coronary lesion. The presence of attended plaque might be an important marker of lesion instability.

  15. Evaluation of Directional Atherectomy Studied by Intravascular Ultrasound in Femoropopliteal Artery Stenosis

    International Nuclear Information System (INIS)

    Tielbeek, Alexander V.; Vroegindeweij, Dammis; Gussenhoven, Elma J.; Buth, Jacob; Landman, Guido H.M.

    1997-01-01

    Purpose: To evaluate the role of intravascular ultrasound (IVUS) before and after directional atherectomy (DA) in the treatment of femoropopliteal artery stenosis. Methods: In 12 patients with 16 stenoses IVUS was performed before and immediately after an angiographically successful DA. This was defined as a diameter reduction (DR) ≤ 50%, which was calculated using the minimal lumen diameter compared with the diameter of a nearby 'normal' segment. In the presence of residual plaque on IVUS an additional DA was performed. Endpoints studied were DR ≤ 30% on IVUS compared with the IVUS findings of the angiographically normal reference segment, or when no additional atherosclerotic material could be removed by further DA passages. Results: Additional DA (mean 1.6 per lesion) had to be performed in all patients. Initial DA increased the cross-sectional free lumen area (FLA) from 3.8 ± 2.0 mm 2 to 8.1 ± 2.7 mm 2 (p= 0.0004). Additional DA increased FLA to 9.3 ± 2.3 mm 2 (p= 0.002) after the second passage and to 9.8 ± 2.4 mm 2 (p= 0.09) after the final DA run. The plaque area (PLA) before DA decreased from 18.1 ± 4.2 mm 2 to 15.4 ± 4.8 mm 2 (p= 0.002) after the first passage, and to 13.5 ± 5.0 mm 2 (p= 0.004) and 12.8 ± 4.4 mm 2 (p= 0.07) after the second and final DA runs, respectively. PLA of the reference segment (9.5 ± 5.7 mm 2 ) was significantly smaller (p= 0.006) than the final PLA of the treated lesion, indicating a large amount of retained plaque. As a result of DA there was an increase in the area bordered by the medial layer, i.e., the total vessel area (from 21.9 ± 4.7 mm 2 to 23.0 ± 4.7 mm 2 ), significantly in eccentric and soft lesions. On IVUS, dissection and plaque rupture after the final passage was seen in 12 of 16 stenoses; two dissections were seen on the completion angiogram. After the final passage in all stenoses except three, the DR with IVUS was ≤ 30%. Conclusion: Lumen enlargement following DA is predominantly due to plaque

  16. Intravascular ultrasound-guided optimized stent deployment. Immediate and 6 months clinical and angiographic results from the Multicenter Ultrasound Stenting in Coronaries Study (MUSIC Study)

    Science.gov (United States)

    de Jaegere, P; Mudra, H; Figulla, H; Almagor, Y; Doucet, S; Penn, I; Colombo, A; Hamm, C; Bartorelli, A; Rothman, M; Nobuyoshi, M; Yamaguchi, T; Voudris, V; DiMario, C; Makovski, S; Hausmann, D; Rowe, S; Rabinovich, S; Sunamura, M; van Es, G A

    1998-08-01

    A study was set up to validate the safety and feasibility of intravascular ultrasound-guided stenting without subsequent anticoagulation, and its impact on the 6 months restenosis rate. The study was designed to be multicentred, prospective, and observational. One hundred and sixty-one patients with stable angina and a de novo coronary artery lesion were enrolled. In four patients, the implantation of a Palmaz-Schatz (with spiral bridge) stent had failed. One of these four patients died 3 days following bypass surgery. In two other patients, intravascular ultrasound assessment was not performed. One hundred and twenty-five of the remaining 155 patients (81%) were treated with aspirin (100 mg x day(-1)), because all three criteria for optimized stent expansion were met. Twenty-two of the remaining 38 patients (25%), in whom at least one criterion was not met were treated with aspirin and acenocoumarol (3 months, INR 2.5-3.5), while 16 patients only received aspirin. Stent thrombosis was documented in two patients (1.3%) for which repeat angioplasty was performed. During the hospital stay, there were no deaths or Q-wave myocardial infarctions. Five patients (3.2%) sustained a non-Q-wave myocardial infarction. During the follow-up period (198+/-38 days, complete for all patients, except one), one patient (0.6%) sustained a Q-wave myocardial infarction, one (0.6%) underwent bypass surgery, and repeat angioplasty was performed in nine patients (5.7%). In two of the nine patients, repeat angioplasty involved another lesion. Therefore, the target lesion revascularization rate during follow-up was 4.5% (seven patients). At quantitative coronary angiography, the minimal lumen diameter (mean+/-SD) increased from 1.12+/-0.34 mm before to 2.89+/-0.35 mm after stenting. Repeat angiography at 6 months was performed in 144 patients (92%). The minimal lumen diameter at follow-up was 2.12+/-0.67 mm. Restenosis (diameter stenosis of 50% or more) was documented in 12 patients or 8

  17. Intravascular ultrasound is a critical tool for accurate endograft sizing in the management of blunt thoracic aortic injury.

    Science.gov (United States)

    Wallace, Gabriel A; Starnes, Benjamin W; Hatsukami, Thomas S; Sobel, Michael; Singh, Niten; Tran, Nam T

    2015-03-01

    Accurate measurement of true aortic luminal diameter (ALD) is critical for endograft sizing in endovascular treatment of blunt thoracic aortic injury (BTAI), but ALD is dynamic and changes with respect to patients' hemodynamic status. This study aimed to characterize how ALD at the time of diagnosis of BTAI compares with ALD at the time of endovascular repair and later at follow-up. This is an Institutional Review Board-approved, single-institution retrospective analysis of prospectively obtained data. Patients were included who presented between July 2007 and December 2012 with computed tomography angiography (CTA)-diagnosed BTAI; who underwent thoracic endovascular aortic repair (TEVAR); and who underwent preoperative CTA, intraoperative intravascular ultrasound (IVUS), and postimplantation CTA. Comparison measurements of the ALD were made among CTA and IVUS images at the level of the left subclavian artery (LSCA) and between initial CTA and postimplantation CTA at 10, 15, and 20 cm distal to the LSCA. Theoretical endograft sizes were determined and compared for each ALD at the LSCA. Twenty-two patients were included in the analysis. Mean age was 38 ± 14 years (range, 17-61 years), with 82% men and mean Injury Severity Score of 43 ± 11 (range, 24-66). Mean time from emergency department admission to initial CTA was -1.2 ± 5 hours (range, -13 to 11.5 hours; negative time implies imaging at an outside facility before admission). Mean time from initial CTA to IVUS was 1.2 ± 1.4 days (range, 2.5 hours-5.7 days) and from IVUS to postimplantation CTA 33 ± 45 days (range, 17 hours-169 days). Overall, ALD measured by IVUS was significantly larger than that by initial CTA (Δ2.5 ± 3.1 mm; P < .05). ALD was also larger at 10, 15, and 20 cm distal to the LSCA in comparing the postimplantation CTA with the initial CTA (Δ2.4, 2.0, and 2.0 mm, respectively; all P < .05). More than half the devices would be sized differently with ALD measured by IVUS at the time of TEVAR

  18. Impact of statin therapy on coronary plaque composition: A systematic review and meta-analysis of virtual histology intravascular ultrasound studies

    NARCIS (Netherlands)

    M. Banach (Maciej); C. Serban (Corina); A. Sahebkar (Amirhossein); D.P. Mikhailidis (Dimitri P.); S. Ursoniu (Sorin); K.K. Ray (Kausik K.); J. Rysz (Jacek); P.P. Toth (Peter); P. Muntner (Paul); S. Mosteoru (Svetlana); H.M. Garcia-Garcia (Hector); G.K. Hovingh (Kees); J.J.P. Kastelein (John); P.W.J.C. Serruys (Patrick)

    2015-01-01

    textabstractBackground: Virtual histology intravascular ultrasound (VH-IVUS) imaging is an innovative tool for the morphological evaluation of coronary atherosclerosis. Evidence for the effects of statin therapy on VH-IVUS parameters have been inconclusive. Consequently, we performed a systematic

  19. Impact of statin therapy on coronary plaque composition: a systematic review and meta-analysis of virtual histology intravascular ultrasound studies

    NARCIS (Netherlands)

    Banach, Maciej; Serban, Corina; Sahebkar, Amirhossein; Mikhailidis, Dimitri P.; Ursoniu, Sorin; Ray, Kausik K.; Rysz, Jacek; Toth, Peter P.; Muntner, Paul; Mosteoru, Svetlana; García-García, Hector M.; Hovingh, G. Kees; Kastelein, John J. P.; Serruys, Patrick W.

    2015-01-01

    Virtual histology intravascular ultrasound (VH-IVUS) imaging is an innovative tool for the morphological evaluation of coronary atherosclerosis. Evidence for the effects of statin therapy on VH-IVUS parameters have been inconclusive. Consequently, we performed a systematic review and meta-analysis

  20. Intravascular ultrasound guided directional atherectomy versus directional atherectomy guided by angiography for the treatment of femoropopliteal in-stent restenosis

    Science.gov (United States)

    Krishnan, Prakash; Tarricone, Arthur; K-Raman, Purushothaman; Majeed, Farhan; Kapur, Vishal; Gujja, Karthik; Wiley, Jose; Vasquez, Miguel; Lascano, Rheoneil A.; Quiles, Katherine G.; Distin, Tashanne; Fontenelle, Ran; Atallah-Lajam, Farah; Kini, Annapoorna; Sharma, Samin

    2017-01-01

    Background: The aim of this study was to compare 1-year outcomes for patients with femoropopliteal in-stent restenosis using directional atherectomy guided by intravascular ultrasound (IVUS) versus directional atherectomy guided by angiography. Methods and results: This was a retrospective analysis for patients with femoropopliteal in-stent restenosis treated with IVUS-guided directional atherectomy versus directional atherectomy guided by angiography from a single center between March 2012 and February 2016. Clinically driven target lesion revascularization was the primary endpoint and was evaluated through medical chart review as well as phone call follow up. Conclusions: Directional atherectomy guided by IVUS reduces clinically driven target lesion revascularization for patients with femoropopliteal in-stent restenosis. PMID:29265002

  1. Bioresorbable Scaffold for Treatment of Coronary Artery Lesions: Intravascular Ultrasound Results From the ABSORB Japan Trial.

    Science.gov (United States)

    Okada, Kozo; Honda, Yasuhiro; Kitahara, Hideki; Otagiri, Kyuhachi; Tanaka, Shigemitsu; Hollak, M Brooke; Yock, Paul G; Popma, Jeffrey J; Kusano, Hajime; Cheong, Wai-Fung; Sudhir, Krishnankutty; Fitzgerald, Peter J; Kimura, Takeshi

    2018-04-09

    The aim of this study was to characterize post-procedural intravascular ultrasound (IVUS) findings in the ABSORB Japan trial, specifically stratified by the size of target coronary arteries. Despite overall noninferiority confirmed in recent randomized trials comparing bioresorbable vascular scaffolds (BVS) (Absorb BVS) and cobalt-chromium everolimus-eluting metallic stents (CoCr-EES), higher event rates of Absorb BVS have been reported with suboptimal deployment, especially in small coronary arteries. In the ABSORB Japan trial, 150 patients (2:1 randomization) were scheduled in the IVUS cohort. Small vessel was defined as mean reference lumen diameter strategy, possibly different between polymeric and metallic devices, needs to be established for bioresorbable scaffold technology. (AVJ-301 Clinical Trial: A Clinical Evaluation of AVJ-301 Absorb™ BVS) in Japanese Population [ABSORB JAPAN]; NCT01844284). Copyright © 2018 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  2. Intravascular ultrasound as a novel tool for the diagnosis and targeted treatment of functional popliteal artery entrapment syndrome

    Directory of Open Access Journals (Sweden)

    Anna E. Boniakowski, MD

    2017-06-01

    Full Text Available Functional popliteal artery entrapment syndrome can be difficult to diagnose, as the imaging modalities presently employed are designed to detect anatomic entrapment. We describe a novel imaging technique to aid in diagnosis in this cohort. A 22-year-old cyclist presented with exercise-limiting claudication. Magnetic resonance angiography with provocative maneuvers was nondiagnostic. Digital subtraction angiography revealed long-segment occlusion of the popliteal artery with plantar flexion; however, the specific site of compression remained unclear. Intravascular ultrasound allowed specific localization of compression and further confirmed the diagnosis. Thus, we report this as an adjunctive imaging modality to definitively diagnose functional popliteal artery entrapment syndrome and to assist in operative planning.

  3. Relative ultrasound energy measurement circuit

    OpenAIRE

    Gustafsson, E.Martin I.; Johansson, Jonny; Delsing, Jerker

    2005-01-01

    A relative ultrasound energy estimation circuit has been designed in a standard 0.35-μm CMOS process, to be a part of a thumb size internet connected wireless ultrasound measurement system. This circuit measures the relative energy between received ultrasound pulses, and presents an output signal that is linear to the received energy. Post-layout simulations indicate 7 bit linearity for 500 mV input signals, 5 μsec startup and stop times, 2.6 mW power consumption during active state. The acti...

  4. Preintervention lesion remodelling affects operative mechanisms of balloon optimised directional coronary atherectomy procedures: a volumetric study with three dimensional intravascular ultrasound

    Science.gov (United States)

    von Birgelen, C; Mintz, G; de Vrey, E A; Serruys, P; Kimura, T; Nobuyoshi, M; Popma, J; Leon, M; Erbel, R; de Feyter, P J

    2000-01-01

    AIMS—To classify atherosclerotic coronary lesions on the basis of adequate or inadequate compensatory vascular enlargement, and to examine changes in lumen, plaque, and vessel volumes during balloon optimised directional coronary atherectomy procedures in relation to the state of adaptive remodelling before the intervention.
DESIGN—29 lesion segments in 29 patients were examined with intravascular ultrasound before and after successful balloon optimised directional coronary atherectomy procedures, and a validated volumetric intravascular ultrasound analysis was performed off-line to assess the atherosclerotic lesion remodelling and changes in plaque and vessel volumes that occurred during the intervention. Based on the intravascular ultrasound data, lesions were classified according to whether there was inadequate (group I) or adequate (group II) compensatory enlargement.
RESULTS—There was no significant difference in patient and lesion characteristics between groups I and II (n = 10 and 19), including lesion length and details of the intervention. Quantitative coronary angiographic data were similar for both groups. However, plaque and vessel volumes were significantly smaller in group I than in II. In group I, 9 (4)% (mean (SD)) of the plaque volume was ablated, while in group II 16 (11)% was ablated (p = 0.01). This difference was reflected in a lower lumen volume gain in group I than in group II (46 (18) mm3 v 80 (49) mm3 (p atherectomy procedures. Plaque ablation was found to be particularly low in lesions with inadequate compensatory vascular enlargement.


Keywords: intravascular ultrasound; ultrasonics; remodelling; coronary artery disease; atherectomy PMID:10648496

  5. Quantitative Ultrasound Measurements at the Heel

    DEFF Research Database (Denmark)

    Daugschies, M.; Brixen, K.; Hermann, P.

    2015-01-01

    Calcaneal quantitative ultrasound can be used to predict osteoporotic fracture risk, but its ability to monitor therapy is unclear possibly because of its limited precision. We developed a quantitative ultrasound device (foot ultrasound scanner) that measures the speed of sound at the heel...... with the foot ultrasound scanner reduced precision errors by half (p quantitative ultrasound measurements is feasible. (E-mail: m.daugschies@rad.uni-kiel.de) (C) 2015 World Federation for Ultrasound in Medicine & Biology....

  6. Variability and accuracy of coronary CT angiography including use of iterative reconstruction algorithms for plaque burden assessment as compared with intravascular ultrasound - an ex vivo study

    Energy Technology Data Exchange (ETDEWEB)

    Stolzmann, Paul [Massachusetts General Hospital and Harvard Medical School, Cardiac MR PET CT Program, Boston, MA (United States); University Hospital Zurich, Institute of Diagnostic and Interventional Radiology, Zurich (Switzerland); Schlett, Christopher L.; Maurovich-Horvat, Pal; Scheffel, Hans; Engel, Leif-Christopher; Karolyi, Mihaly; Hoffmann, Udo [Massachusetts General Hospital and Harvard Medical School, Cardiac MR PET CT Program, Boston, MA (United States); Maehara, Akiko; Ma, Shixin; Mintz, Gary S. [Columbia University Medical Center, Cardiovascular Research Foundation, New York, NY (United States)

    2012-10-15

    To systematically assess inter-technique and inter-/intra-reader variability of coronary CT angiography (CTA) to measure plaque burden compared with intravascular ultrasound (IVUS) and to determine whether iterative reconstruction algorithms affect variability. IVUS and CTA data were acquired from nine human coronary arteries ex vivo. CT images were reconstructed using filtered back projection (FBPR) and iterative reconstruction algorithms: adaptive-statistical (ASIR) and model-based (MBIR). After co-registration of 284 cross-sections between IVUS and CTA, two readers manually delineated the cross-sectional plaque area in all images presented in random order. Average plaque burden by IVUS was 63.7 {+-} 10.7% and correlated significantly with all CTA measurements (r = 0.45-0.52; P < 0.001), while CTA overestimated the burden by 10 {+-} 10%. There were no significant differences among FBPR, ASIR and MBIR (P > 0.05). Increased overestimation was associated with smaller plaques, eccentricity and calcification (P < 0.001). Reproducibility of plaque burden by CTA and IVUS datasets was excellent with a low mean intra-/inter-reader variability of <1/<4% for CTA and <0.5/<1% for IVUS respectively (P < 0.05) with no significant difference between CT reconstruction algorithms (P > 0.05). In ex vivo coronary arteries, plaque burden by coronary CTA had extremely low inter-/intra-reader variability and correlated significantly with IVUS measurements. Accuracy as well as reader reliability were independent of CT image reconstruction algorithm. (orig.)

  7. Mechanism of lumen gain with a novel rotational aspiration atherectomy system for peripheral arterial disease: examination by intravascular ultrasound.

    Science.gov (United States)

    Hassan, Ali H M; Ako, Junya; Waseda, Katsuhisa; Honda, Yasuhiro; Zeller, Thomas; Leon, Martin B; Fitzgerald, Peter J

    2010-01-01

    The purpose of this study was to evaluate the mechanism of luminal gain with a novel atheroablation system (Pathway PV) for the treatment of peripheral artery disease using intravascular ultrasound (IVUS). The atherectomy system is a rotational atherectomy device, which employs expandable rotating blades with ports that allow flushing and aspiration of the plaque material or thrombus. In this first-in-man clinical study, IVUS analysis was available in 6 patients with lower limb ischemia treated with this device. The treatment results were assessed using IVUS at pre and post atherectomy. Lumen beyond burr size (LBB) was defined as lumen gain divided by the estimated burr area determined by the burr-size. IVUS analysis was available in six patients (superficial femoral artery n=3, popliteal artery n=2, posterior tibial artery n=1). Atheroablation achieved a significant increase in lumen area (LA) (preintervention 3.9+/-0.4, postatheroablation 8.0+/-1.7 mm(2), Patherectomy device achieved significant luminal gain by debulking in the absence of vessel stretching. The LA was greater than burr-sized lumen expectancy at cross-sections along the treated segments, suggesting a complimentary role of aspiration in luminal gain in atherosclerotic peripheral artery lesions.

  8. Detection of attenuated plaque in stable angina with 64-multidetector computed tomography: a comparison with intravascular ultrasound.

    Science.gov (United States)

    Jinzaki, Masahiro; Okabe, Teruo; Endo, Ayaka; Kawamura, Akio; Koga, Seiko; Yamada, Minoru; Fukuda, Keiichi; Kuribayashi, Sachio

    2012-01-01

    To clarify multidetector computed tomography (MDCT) findings of attenuated plaque detected by intravascular ultrasound (IVUS). One hundred and fifty-four patients with stable angina underwent MDCT before IVUS. The attenuated plaque was identified in the targeted artery with IVUS, and the same artery was analyzed with MDCT for the presence of a high density area (HDA) >130 Hounsfield units (HU), and a low density area (LDA) HDA in attenuated plaque was compared with that in calcified plaque. Ten attenuated plaques and 15 calcified plaques were identified in 9 of 154 patients (males=9, 66.2 ± 9.5 years). Eight of the 10 attenuated plaques and all 15 calcified plaques were accompanied with a HDA on MDCT. The HDA ranged from 174 to 667 HU (mean 389.0 ± 148.3 HU) in the 8 attenuated plaques, and from 545 to 1,205 HU (mean 920.9 ± 215.9 HU) in 15 calcified plaques. There was a significant difference in CT density of the HDA between the attenuated and calcified plaque (PHDA. MDCT has the ability to demonstrate attenuated plaque as the combination of HDA (approximately 400 HU on average) and LDA HDA can be differentiated from calcified plaque by its lower CT density value.

  9. In vivo evaluation of axial integrity of coronary stents using intravascular ultrasound: Insights on longitudinal stent deformation.

    Science.gov (United States)

    Dvir, Danny; Kitabata, Hironori; Barbash, Israel M; Minha, Sa'ar; Badr, Salem; Loh, Joshua P; Chen, Fang; Torguson, Rebecca; Waksman, Ron

    2014-09-01

    To evaluate the axial integrity of different coronary stents using intravascular ultrasound (IVUS). Longitudinal stent deformation was recently reported. Consecutive patients who underwent IVUS analysis after drug-eluting stent (DES) implantation for de novo coronary lesions were evaluated. Stent length was compared with label length for calculation of absolute change and relative difference (absolute change divided by label length). A total of 233 DES utilizing five different platforms were included. The median absolute change in stent length was 0.90 mm (interquartile range [IQR] 0.48-1.39) and the relative difference was 5.24% (IQR 2.55-8.29). There was no significant difference among the groups in median absolute or relative change: Cypher 0.89 mm/3.89%, Taxus 0.88 mm/5.39%, Endeavor 1.16 mm/6.77%, Xience V 0.86 mm/5.80%, and PROMUS Element 0.79 mm/5.34% (P = 0.085, P = 0.072, respectively). Multivariate logistic regression revealed that the Cypher stent was independently correlated with a lower change in length, whereas stent label length and deployment pressure were correlated with higher absolute change. The axial integrity of DES platforms examined in vivo was high, with only mild changes in stent length after implantation. While there are differences between first- and second-generation DES, axial integrity among second-generation DES was similar. © 2013 Wiley Periodicals, Inc.

  10. Accuracy of multidetector row computed tomography for the detection of transplant vasculopathy: comparison with invasive coronary angiography and intravascular ultrasound

    International Nuclear Information System (INIS)

    Carrascosa, P.; Capunay, C.; Carrascosa, J.; Perrone, S.; Deviggiano, A.; Lopez, E.M.; Lev, G.; Garcia, M.J.

    2009-01-01

    Objective: To evaluate the diagnostic accuracy of multidetector computed tomography (MDCT) for detection of luminal stenosis and cardiac allograft vasculopathy in comparison with coronary angiography (CA) and intravascular ultrasound (IVUS) respectively. Material and methods: Nineteen cardiac transplant patients scheduled for follow-up CA were included. MDCT coronary angiography was performed using a 16-row CT scanner within 7-14 days after CA and IVUS. Studies were analyzed by independent readers; two observers evaluated the CT datasets for the presence of coronary artery stenosis > 50% and allograft vasculopathy. Results: The sensitivity for detecting > 50% luminal stenosis was 80-88% and specificity, 98-99% and for detection of cardiac allograft vasculopathy, the sensitivity was 91-96% and specificity, 88-91%. Conclusion: In this preliminary series, our results indicate that MDCT coronary angiography was capable of detecting both significant coronary stenosis as well as diffuse intimal proliferation. This non-invasive procedure could be an alternative to CA and IVUS in the surveillance of heart transplant patients. (authors) [es

  11. Antiatherosclerotic effects of long-term maximally intensive statin therapy after acute coronary syndrome: insights from Study of Coronary Atheroma by Intravascular Ultrasound: Effect of Rosuvastatin Versus Atorvastatin.

    Science.gov (United States)

    Puri, Rishi; Nissen, Steven E; Shao, Mingyuan; Ballantyne, Christie M; Barter, Philip J; Chapman, M John; Erbel, Raimund; Libby, Peter; Raichlen, Joel S; Uno, Kiyoko; Kataoka, Yu; Nicholls, Stephen J

    2014-11-01

    Patients with acute coronary syndromes (ACS) display diffuse coronary atheroma instability and heightened risk of early and late recurrent coronary events. We compared the long-term antiatherosclerotic efficacy of high-intensity statins in patients with ACS when compared with stable disease. Study of Coronary Atheroma by Intravascular Ultrasound: Effect of Rosuvastatin Versus Atorvastatin (SATURN) used serial intravascular ultrasound measures of coronary atheroma volume in patients treated with rosuvastatin 40 mg or atorvastatin 80 mg for 24 months. The overall effect of high-intensity statins on the change in coronary percent atheroma volume and major adverse cardiovascular events (death/nonfatal myocardial infarction/coronary revascularization) were evaluated in this post hoc analysis. When compared with non-ACS patients (n=678), patients with ACS (n=361) were younger, actively smoking, and have had a previous myocardial infarction (all P<0.001). At baseline, patients with ACS exhibited lower high-density lipoprotein cholesterol (43.5±11 versus 45.8±11 mg/dL; P=0.002), a higher apolipoprotein B: apolipoprotein A-1 ratio (0.90±0.24 versus 0.83±0.24; P<0.001) and greater percent atheroma volume (37.3±8.5% versus 35.9±8.1%; P=0.01) when compared with non-ACS patients. Despite similar achieved levels of lipid and inflammatory markers after high-intensity statin therapy, patients with ACS demonstrated greater percent atheroma volume regression than non-ACS patients (-1.46±0.14 versus -0.89±0.13; P=0.003). After propensity-weighted multivariable adjustment, baseline percent atheroma volume (P<0.001) and an ACS clinical presentation (P=0.02) independently associated with plaque regression. The 24-month major adverse cardiovascular events-free survival was similar between patients with ACS and non-ACS (90.6 versus 92.9%; P=0.25). Long-term high-intensity statin therapy caused greater plaque regression and comparable major adverse cardiovascular events rates in

  12. Early characterization of atherosclerotic coronary plaques with multidetector computed tomography in patients with acute coronary syndrome. A comparative study with intravascular ultrasound

    Energy Technology Data Exchange (ETDEWEB)

    Iriart, Xavier; Dos-Santos, Pierre [Universite Bordeaux 2, Inserm U. 441 Atherosclerose, Bordeaux (France); Brunot, Sebastien [CHU de Bordeaux, Hopital du Haut-Leveque, Unite d' Imagerie Thoracique et Cardiovasculaire, Pessac (France); Unite de Soins Intensifs Cardiologiques, Pessac (France); Unite d' Imagerie Thoracique et Cardiovasculaire, Hopital Cardiologique, Pessac (France); Coste, Pierre; Leroux, Lionel [Universite Bordeaux 2, Inserm U. 441 Atherosclerose, Bordeaux (France); Unite de Soins Intensifs Cardiologiques, Pessac (France); Montaudon, Michel [Universite Bordeaux 2, Inserm U. 885 F 33076, Bordeaux (France); CHU de Bordeaux, Hopital du Haut-Leveque, Unite d' Imagerie Thoracique et Cardiovasculaire, Pessac (France); Labeque, Jean-Noel; Jais, Catherine [Unite de Soins Intensifs Cardiologiques, Pessac (France); Laurent, Francois [Universite Bordeaux 2, Inserm U. 885 F 33076, Bordeaux (France); CHU de Bordeaux, Hopital du Haut-Leveque, Unite d' Imagerie Thoracique et Cardiovasculaire, Pessac (France); Unite d' Imagerie Thoracique et Cardiovasculaire, Hopital Cardiologique, Pessac (France)

    2007-10-15

    We compared 16-slice computed tomography (CT) with intravascular ultrasound (IVUS) in their ability to identify the culprit lesion, and to assess plaque characterization and vascular remodelling in acute coronary syndrome (ACS). Twenty patients were prospectively studied. Coronary plaque identification and characterization were compared using 16-slice CT and 40-MHz catheter-based IVUS. Minimum lumen area (MLA), cross-sectional vessel area (CVA) and vessel remodelling were determined for each comparable lesion. One hundred and sixty-nine segments were compared and 84 plaques analysed. Sixteen-slice CT detected 95% of culprit lesions (19/20). No feature suggestive of plaque rupture was detected by 16-slice CT. Attenuation measurements within all lesions revealed different values for hypoechoic (38 {+-} 33 HU), hyperechoic (94 {+-} 44 HU), and calcified plaques (561 {+-} 216 HU), (P < 0.001). Agreement between 16-slice CT and IVUS on measuring MLA and CVA was evaluated using Bland-Altman analysis. Pearson and intra-class coefficient (ICC) were 0.81 and 0.70 for MLA, and 0.81 and 0.36 for CVA, for 16-slice CT and IVUS, respectively. Agreement between both techniques for vessel positive remodelling was moderate (kappa = 0.54, P < 0.001). Sixteen-slice CT has shown moderate accuracy in quantifying and characterizing coronary plaques compared with IVUS. Spatial resolution of 16-slice CT remains a major limitation, however, to accurately assess the complex lesions involved in ACS. (orig.)

  13. A study of coronary artery rotational motion with dense scale-space optical flow in intravascular ultrasound

    Energy Technology Data Exchange (ETDEWEB)

    Danilouchkine, M G; Mastik, F; Steen, A F W van der [Department of Biomedical Engineering, Erasmus Medical Center, Ee2302, PO Box 2040, 3000 CA, Rotterdam (Netherlands)], E-mail: m.danilouchkine@ErasmusMC.nl, E-mail: f.mastik@ErasmusMC.nl, E-mail: a.vandersteen@ErasmusMC.nl

    2009-03-21

    This paper describes a novel method for estimating tissue motion in two-dimensional intravascular ultrasound (IVUS) images of a coronary artery. It is based on the classical Lukas-Kanade (LK) algorithm for optical flow (OF). The OF vector field quantifies the amount of misalignment between two consecutive frames in a sequence of images. From the theoretical standpoint, two fundamental improvements are proposed in this paper. First, using a simplified representation of the vessel wall as a medium with randomly distributed scatterers, it was shown that the OF equation satisfies the integral brightness conservation law. Second, a scale-space embedding for the OF equation was derived under the assumption of spatial consistency in IVUS acquisitions. The spatial coherence is equivalent to a locally affine motion model. The latter effectively captures and appropriately describes a complex deformation pattern of the coronary vessel wall under the varying physiological conditions (i.e. pulsatile blood pressure). The accuracy of OF tracking was estimated on the tissue-mimicking phantoms subjected to the controlled amount of angular deviation. Moreover, the performance of the classical LK and proposed approach was compared using the simulated IVUS images with an atherosclerotic lesion. The experimental results showed robust and reliable performance of up to 5{sup 0} of rotation, which is within the plausible range of circumferential displacement of the coronary arteries. Subsequently, the algorithm was used to analyze vessel wall motion in 18 IVUS pullbacks from 16 patients. The in vivo experiments revealed that the motion of coronary arteries is primarily determined by the cardiac contraction.

  14. Near-Infrared Spectroscopy Enhances Intravascular Ultrasound Assessment of Vulnerable Coronary Plaque: A Combined Pathological and In Vivo Study.

    Science.gov (United States)

    Puri, Rishi; Madder, Ryan D; Madden, Sean P; Sum, Stephen T; Wolski, Kathy; Muller, James E; Andrews, Jordan; King, Karilane L; Kataoka, Yu; Uno, Kiyoko; Kapadia, Samir R; Tuzcu, E Murat; Nissen, Steven E; Virmani, Renu; Maehara, Akiko; Mintz, Gary S; Nicholls, Stephen J

    2015-11-01

    Pathological studies demonstrate the dual significance of plaque burden (PB) and lipid composition for mediating coronary plaque vulnerability. We evaluated relationships between intravascular ultrasound (IVUS)-derived PB and arterial remodeling with near-infrared spectroscopy (NIRS)-derived lipid content in ex vivo and in vivo human coronary arteries. Ex vivo coronary NIRS and IVUS imaging was performed through blood in 116 coronary arteries of 51 autopsied hearts, followed by 2-mm block sectioning (n=2070) and histological grading according to modified American Heart Association criteria. Lesions were defined as the most heavily diseased 2-mm block per imaged artery on IVUS. IVUS-derived PB and NIRS-derived lipid core burden index (LCBI) of each block and lesion were analyzed. Block-level analysis demonstrated significant trends of increasing PB and LCBI across more complex atheroma (Ptrend <0.001 for both LCBI and PB). Lesion-based analyses demonstrated the highest LCBI and remodeling index within coronary fibroatheroma (Ptrend <0.001 and 0.02 versus all plaque groups, respectively). Prediction models demonstrated similar abilities of PB, LCBI, and remodeling index for discriminating fibroatheroma (c indices: 0.675, 0.712, and 0.672, respectively). A combined PB+LCBI analysis significantly improved fibroatheroma detection accuracy (c index 0.77, P=0.028 versus PB; net-reclassification index 43%, P=0.003), whereas further adding remodeling index did not (c index 0.80, P=0.27 versus PB+LCBI). In vivo comparisons of 43 age- and sex-matched patients (to the autopsy cohort) undergoing combined NIRS-IVUS coronary imaging yielded similar associations to those demonstrated ex vivo. Adding NIRS to conventional IVUS-derived PB imaging significantly improves the ability to detect more active, potentially vulnerable coronary atheroma. © 2015 American Heart Association, Inc.

  15. A new method for real-time co-registration of 3D coronary angiography and intravascular ultrasound or optical coherence tomography.

    Science.gov (United States)

    Carlier, Stéphane; Didday, Rich; Slots, Tristan; Kayaert, Peter; Sonck, Jeroen; El-Mourad, Mike; Preumont, Nicolas; Schoors, Dany; Van Camp, Guy

    2014-06-01

    We present a new clinically practical method for online co-registration of 3D quantitative coronary angiography (QCA) and intravascular ultrasound (IVUS) or optical coherence tomography (OCT). The workflow is based on two modified commercially available software packages. Reconstruction steps are explained and compared to previously available methods. The feasibility for different clinical scenarios is illustrated. The co-registration appears accurate, robust and induced a minimal delay on the normal cath lab activities. This new method is based on the 3D angiographic reconstruction of the catheter path and does not require operator's identification of landmarks to establish the image synchronization. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. A new method for real-time co-registration of 3D coronary angiography and intravascular ultrasound or optical coherence tomography

    International Nuclear Information System (INIS)

    Carlier, Stéphane; Didday, Rich; Slots, Tristan; Kayaert, Peter; Sonck, Jeroen; El-Mourad, Mike; Preumont, Nicolas; Schoors, Dany; Van Camp, Guy

    2014-01-01

    We present a new clinically practical method for online co-registration of 3D quantitative coronary angiography (QCA) and intravascular ultrasound (IVUS) or optical coherence tomography (OCT). The workflow is based on two modified commercially available software packages. Reconstruction steps are explained and compared to previously available methods. The feasibility for different clinical scenarios is illustrated. The co-registration appears accurate, robust and induced a minimal delay on the normal cath lab activities. This new method is based on the 3D angiographic reconstruction of the catheter path and does not require operator’s identification of landmarks to establish the image synchronization

  17. A new method for real-time co-registration of 3D coronary angiography and intravascular ultrasound or optical coherence tomography

    Energy Technology Data Exchange (ETDEWEB)

    Carlier, Stéphane, E-mail: sgcarlier@hotmail.com [Department of Cardiology, Universitair Ziekenhuis - UZ Brussel, Brussels (Belgium); Department of Cardiology, Erasme University Hospital, Université Libre de Bruxelles (ULB), Brussels (Belgium); Didday, Rich [INDEC Medical Systems Inc., Santa Clara, CA (United States); Slots, Tristan [Pie Medical Imaging BV, Maastricht (Netherlands); Kayaert, Peter; Sonck, Jeroen [Department of Cardiology, Universitair Ziekenhuis - UZ Brussel, Brussels (Belgium); El-Mourad, Mike; Preumont, Nicolas [Department of Cardiology, Erasme University Hospital, Université Libre de Bruxelles (ULB), Brussels (Belgium); Schoors, Dany; Van Camp, Guy [Department of Cardiology, Universitair Ziekenhuis - UZ Brussel, Brussels (Belgium)

    2014-06-15

    We present a new clinically practical method for online co-registration of 3D quantitative coronary angiography (QCA) and intravascular ultrasound (IVUS) or optical coherence tomography (OCT). The workflow is based on two modified commercially available software packages. Reconstruction steps are explained and compared to previously available methods. The feasibility for different clinical scenarios is illustrated. The co-registration appears accurate, robust and induced a minimal delay on the normal cath lab activities. This new method is based on the 3D angiographic reconstruction of the catheter path and does not require operator’s identification of landmarks to establish the image synchronization.

  18. Prospective implementation of an algorithm for bedside intravascular ultrasound-guided filter placement in critically ill patients.

    Science.gov (United States)

    Killingsworth, Christopher D; Taylor, Steven M; Patterson, Mark A; Weinberg, Jordan A; McGwin, Gerald; Melton, Sherry M; Reiff, Donald A; Kerby, Jeffrey D; Rue, Loring W; Jordan, William D; Passman, Marc A

    2010-05-01

    Although contrast venography is the standard imaging method for inferior vena cava (IVC) filter insertion, intravascular ultrasound (IVUS) imaging is a safe and effective option that allows for bedside filter placement and is especially advantageous for immobilized critically ill patients by limiting resource use, risk of transportation, and cost. This study reviewed the effectiveness of a prospectively implemented algorithm for IVUS-guided IVC filter placement in this high-risk population. Current evidence-based guidelines were used to create a clinical decision algorithm for IVUS-guided IVC filter placement in critically ill patients. After a defined lead-in phase to allow dissemination of techniques, the algorithm was prospectively implemented on January 1, 2008. Data were collected for 1 year using accepted reporting standards and a quality assurance review performed based on intent-to-treat at 6, 12, and 18 months. As defined in the prospectively implemented algorithm, 109 patients met criteria for IVUS-directed bedside IVC filter placement. Technical feasibility was 98.1%. Only 2 patients had inadequate IVUS visualization for bedside filter placement and required subsequent placement in the endovascular suite. Technical success, defined as proper deployment in an infrarenal position, was achieved in 104 of the remaining 107 patients (97.2%). The filter was permanent in 21 (19.6%) and retrievable in 86 (80.3%). The single-puncture technique was used in 101 (94.4%), with additional dual access required in 6 (5.6%). Periprocedural complications were rare but included malpositioning requiring retrieval and repositioning in three patients, filter tilt >/=15 degrees in two, and arteriovenous fistula in one. The 30-day mortality rate for the bedside group was 5.5%, with no filter-related deaths. Successful placement of IVC filters using IVUS-guided imaging at the bedside in critically ill patients can be established through an evidence-based prospectively

  19. Effect of cilostazol on in-stent neointimal hyperplasia after coronary artery stenting. A quantitative coronary angiography and volumetric intravascular ultrasound study

    International Nuclear Information System (INIS)

    Min, Pil-Ki; Jung, Jae-Hun; Ko, Young-Guk; Choi, Donghoon; Jang, Yangsoo; Shim, Won-Heum

    2007-01-01

    This study was designed to investigate the efficacy of cilostazol on the prevention of in-stent neointimal hyperplasia as measured by both quantitative coronary angiography (CAG) and volumetric intravascular ultrasound (IVUS). Fifty-nine patients (39 men, age 62 years) undergoing elective coronary stenting were randomly assigned to receive aspirin plus clopidogrel or ticlopidine (Group I, n=28, 30 lesions) or aspirin plus clopidogrel or ticlopidine plus cilostazol (Group II, n=31, 35 lesions). CAG and IVUS were performed and repeated at 6 months to assess the primary endpoints of minimal luminal diameter (MLD) and in-stent neointimal hyperplasia volume. Follow-up CAG was performed on all patients and follow-up IVUS study was available for 50 lesions in 48 patients (24 lesions in Group I, 26 in Group II). There were no significant differences in the baseline angiographic data between the 2 groups. At 6 months follow-up, in-stent MLD was 1.90±0.76 mm in Group I and 2.41±0.85 mm in Group II (p=0.006). Volumetric IVUS at 6 months demonstrated that in-stent intimal hyperplasia volume per stent length was 2.2±1.4 mm 3 /mm in Group I and 1.0±0.5 mm 3 /mm in Group II (p=0.001). Triple antiplatelet therapy including cilostazol seems to be more effective at preventing in-stent neointimal hyperplasia than a dual antiplatelet regimen. (author)

  20. Influence of high-dose lipid lowering treatment compared to low-dose lipid lowering treatment on plaque composition assessed by intravascular ultrasound virtual histology in patients with ST-segment elevation acute myocardial infarction

    DEFF Research Database (Denmark)

    Egede, Rasmus; Jensen, Lisette Okkels; Hansen, Henrik Steen

    2013-01-01

    Aims: The aim of this study was to evaluate the effect of low-dose versus high-dose rosuvastatin therapy on the necrotic core content in coronary plaques of angiographic non-significant lesions as assessed by intravascular ultrasound - virtual histology. Methods and results: Eighty-seven statin...

  1. Intravascular ultrasound and angiographic demonstration of left main stem thrombus-high-risk presentation in a young adult with anabolic steroid abuse.

    Science.gov (United States)

    Garg, Pankaj; Davis, Gershan; Wilson, John Ian; Sivananthan, Mohan

    2010-01-01

    We present a case of acute myocardial infarction in a young adult with a history of anabolic steroid abuse. On diagnostic coronary angiography and intravascular ultrasound, he was found to have a distal left main stem thrombus extending into the proximal left anterior descending artery and a large intermediate vessel. As he was hemodynamically stable and pain-free, he was managed conservatively with triple antiplatelet therapy (aspirin, clopidogrel, and abciximab). This was also to avoid the risk of 'wiring the vessel,' especially if there was underlying dissection. Repeat angiography a few weeks later showed complete thrombus resolution. This is the first reported case of extensive left main stem thrombus in a young patient with anabolic steroid abuse. Management of such cases is not straightforward and our case highlights one approach to both diagnosis and treatment.

  2. Induction Therapy With Antithymocyte Globulin in Patients Undergoing Cardiac Transplantation Is Associated With Decreased Coronary Plaque Progression as Assessed by Intravascular Ultrasound.

    Science.gov (United States)

    Azarbal, Babak; Cheng, Richard; Vanichsarn, Christopher; Patel, Jignesh K; Czer, Lawrence S; Chang, David H; Kittleson, Michelle M; Kobashigawa, Jon A

    2016-01-01

    Antithymocyte globulin (ATG) is used as induction therapy after cardiac transplant for enhancing immunosuppression and delaying the initiation of nephrotoxic drugs. It is unknown if ATG induction is associated with decreased coronary plaque progression by intravascular ultrasound (IVUS). Patients transplanted between March 2010 and December 2012 with baseline and 1-year IVUS were included. All patients transplanted were included in a secondary analysis. Change in plaque progression was measured in a blinded fashion on matched coronary segments and contrasted between patients induced with ATG and those who were not. One hundred and three patients were included in IVUS arms. Mean age at transplant was 55.8 ± 12.6 years, and 33.0% were female. Patients induced with ATG were more sensitized (54.3% versus 14.3%). Plaque progression was attenuated in patients who received ATG by changes in maximal intimal area (1.0 ± 1.2 versus 2.3 ± 2.6 mm(2); P = 0.001), maximal percent stenosis (6.3 ± 7.9 versus 12.8 ± 12.3%; = 0.003), maximal intimal thickness (0.2 ± 0.2 versus 0.3 ± 0.3 mm; P = 0.035), and plaque volume (0.5 ± 0.7 versus 1.0 ± 1.3 mm(3)/mm; P = 0.016). Rapid plaque progression by maximal percent stenosis (≥ 20%) occurred less frequently in the ATG arm (4.3% versus 26.3; P = 0.003). Survival (P = 0.242) and any treated rejection (P = 0.166) were not statistically different between groups. Patients receiving ATG had a higher rate of first-year infection (P = 0.003), perhaps related to increased intravenous antibiotic use immediately postoperatively, and a trend toward more biopsy-proven rejection (P = 0.073). Induction therapy with ATG is associated with reduced first-year coronary plaque progression as assessed by IVUS, despite an increased prevalence of sensitized patients with a trend toward more rejection. © 2016 American Heart Association, Inc.

  3. Intravascular photoacoustic imaging of human coronary atherosclerosis

    Science.gov (United States)

    Jansen, Krista; van der Steen, Antonius F. W.; Springeling, Geert; van Beusekom, Heleen M. M.; Oosterhuis, J. Wolter; van Soest, Gijs

    2011-03-01

    We demonstrate intravascular photoacoustic imaging of human coronary atherosclerotic plaque. We specifically imaged lipid content, a key factor in vulnerable plaques that may lead to myocardial infarction. An integrated intravascular photoacoustics (IVPA) and ultrasound (IVUS) catheter with an outer diameter of 1.25 mm was developed. The catheter comprises an angle-polished optical fiber adjacent to a 30 MHz single-element transducer. The ultrasonic transducer was optically isolated to eliminate artifacts in the PA image. We performed measurements on a cylindrical vessel phantom and isolated point targets to demonstrate its imaging performance. Axial and lateral point spread function widths were 110 μm and 550 μm, respectively, for PA and 89 μm and 420 μm for US. We imaged two fresh human coronary arteries, showing different stages of disease, ex vivo. Specific photoacoustic imaging of lipid content, is achieved by spectroscopic imaging at different wavelengths between 1180 and 1230 nm.

  4. Late lumen loss and intima hyperplasia after sirolimus-eluting and zotarolimus-eluting stent implantation in diabetic patients: the diabetes and drug-eluting stent (DiabeDES III) angiography and intravascular ultrasound trial

    DEFF Research Database (Denmark)

    Jensen, Lisette Okkels; Mæng, Michael; Thayssen, Per

    2011-01-01

    Patients with diabetes mellitus have increased risk of in-stent restenosis after coronary stent implantation due to neointimal hyperplasia (NIH). The aim of this study was to use quantitative coronary angiography (QCA) and volumetric intravascular ultrasound (IVUS) to evaluate the effects...... of the sirolimus-eluting Cypher® stent (SES) and the zotarolimus-eluting Endeavor® stent (ZES) on angiographic late lumen loss and intima hyperplasia in diabetic patients....

  5. Measurement of tissue viscoelasticity with ultrasound

    Science.gov (United States)

    Greenleaf, J. F.; Alizad, A.

    2017-02-01

    Tissue properties such as elasticity and viscosity have been shown to be related to such tissue conditions as contraction, edema, fibrosis, and fat content among others. Magnetic Resonance Elastography has shown outstanding ability to measure the elasticity and in some cases the viscosity of tissues, especially in the liver, providing the ability to stage fibrotic liver disease similarly to biopsy. We discuss ultrasound methods of measuring elasticity and viscosity in tissues. Many of these methods are becoming widely available in the extant ultrasound machines distributed throughout the world. Some of the methods to be discussed are in the developmental stage. The advantages of the ultrasound methods are that the imaging instruments are widely available and that many of the viscoelastic measurements can be made during a short addition to the normal ultrasound examination time. In addition, the measurements can be made by ultrasound repetitively and quickly allowing evaluation of dynamic physiologic function in circumstances such as muscle contraction or artery relaxation. Measurement of viscoelastic tissue mechanical properties will become a consistent part of clinical ultrasound examinations in our opinion.

  6. Consensus standards for acquisition, measurement, and reporting of intravascular optical coherence tomography studies: a report from the International Working Group for Intravascular Optical Coherence Tomography Standardization and Validation

    DEFF Research Database (Denmark)

    Falk, Erling

    2012-01-01

    The purpose of this document is to make the output of the International Working Group for Intravascular Optical Coherence Tomography (IWG-IVOCT) Standardization and Validation available to medical and scientific communities, through a peer-reviewed publication, in the interest of improving...

  7. Consensus standards for acquisition, measurement, and reporting of intravascular optical coherence tomography studies : A report from the International Working Group for Intravascular Optical Coherence Tomography Standardization and Validation

    NARCIS (Netherlands)

    G.J. Tearney (Guillermo); E.S. Regar (Eveline); T. Akasaka (Takashi); S. Adriaenssens (Stef); P. Barlis (Peter); H.G. Bezerra (Hiram); B.E. Bouma (Brett); N. Bruining (Nico); J.-M. Cho (Jin-Man); S. Chowdhary (Saqib); M.A. Costa (Marco); R. de Silva (Ranil); J. Dijkstra (Jouke); C. di Mario (Carlo); D. Dudeck (Darius); E. Falk (Erling); M.D. Feldman (Marc); P.J. Fitzgerald (Peter); H.M. Garcia-Garcia (Hector); N. Gonzalo (Nieves); J.F. Granada (Juan); G. Guagliumi (Giulio); N.R. Holm (Niels); Y. Honda (Yasuhiro); F. Ikeno (Fumiaki); Y. Kawasaki; W. Kochman (Waclav); L. Koltowski (Lukasz); T. Kubo (Takashi); T. Kume (Teruyoshi); H. Kyono (Hiroyuki); C.C.S. Lam (Cheung Chi Simon); G. Lamouche (Guy); D.P. Lee (David); M.B. Leon (Martin); A. Maehara (Akiko); O. Manfrini (Olivia); G.S. Mintz (Gary); K. Mizuno (Kyiouchi); M-A.M. Morel (Marie-Angèle); S. Nadkarni (Seemantini); H. Okura (Hiroyuki); H. Otake (Hiromasa); A. Pietrasik (Arkadiusz); F. Prati (Francesco); L. Rber (Lorenz); M. Radu (Maria); N. Rieber (Nikolaus); M. Riga (Maria); S.M. Rollins; M. Rosenberg (Mireille); V. Sirbu (Vasile); P.W.J.C. Serruys (Patrick); K. Shimada; T. Shinke (Toshiro); J. Shite (Junya); E. Siegel (Eliot); S. Sonada (Shinjo); U. Suter (Ueli); S. Takarada (Shigeho); A. Tanaka (Atsushi); M. Terashima (Mitsuyasu); T. Troels (Thim); M. Uemura (Mayu); G.J. Ughi (Giovanni); H.M.M. van Beusekom (Heleen); A.F.W. van der Steen (Ton); G.A. van Es (Gerrit Anne); G. van Soest (Gijs); R. Virmani (Renu); S. Waxman (Sergio); N.J. Weissman (Neil); G. Weisz (Giora)

    2012-01-01

    textabstractObjectives: The purpose of this document is to make the output of the International Working Group for Intravascular Optical Coherence Tomography (IWG-IVOCT) Standardization and Validation available to medical and scientific communities, through a peer-reviewed publication, in the

  8. Optical coherence tomography compared with intravascular ultrasound and with angiography to guide coronary stent implantation (ILUMIEN III: OPTIMIZE PCI): a randomised controlled trial.

    Science.gov (United States)

    Ali, Ziad A; Maehara, Akiko; Généreux, Philippe; Shlofmitz, Richard A; Fabbiocchi, Franco; Nazif, Tamim M; Guagliumi, Giulio; Meraj, Perwaiz M; Alfonso, Fernando; Samady, Habib; Akasaka, Takashi; Carlson, Eric B; Leesar, Massoud A; Matsumura, Mitsuaki; Ozan, Melek Ozgu; Mintz, Gary S; Ben-Yehuda, Ori; Stone, Gregg W

    2016-11-26

    Percutaneous coronary intervention (PCI) is most commonly guided by angiography alone. Intravascular ultrasound (IVUS) guidance has been shown to reduce major adverse cardiovascular events (MACE) after PCI, principally by resulting in a larger postprocedure lumen than with angiographic guidance. Optical coherence tomography (OCT) provides higher resolution imaging than does IVUS, although findings from some studies suggest that it might lead to smaller luminal diameters after stent implantation. We sought to establish whether or not a novel OCT-based stent sizing strategy would result in a minimum stent area similar to or better than that achieved with IVUS guidance and better than that achieved with angiography guidance alone. In this randomised controlled trial, we recruited patients aged 18 years or older undergoing PCI from 29 hospitals in eight countries. Eligible patients had one or more target lesions located in a native coronary artery with a visually estimated reference vessel diameter of 2·25-3·50 mm and a length of less than 40 mm. We excluded patients with left main or ostial right coronary artery stenoses, bypass graft stenoses, chronic total occlusions, planned two-stent bifurcations, and in-stent restenosis. Participants were randomly assigned (1:1:1; with use of an interactive web-based system in block sizes of three, stratified by site) to OCT guidance, IVUS guidance, or angiography-guided stent implantation. We did OCT-guided PCI using a specific protocol to establish stent length, diameter, and expansion according to reference segment external elastic lamina measurements. All patients underwent final OCT imaging (operators in the IVUS and angiography groups were masked to the OCT images). The primary efficacy endpoint was post-PCI minimum stent area, measured by OCT at a masked independent core laboratory at completion of enrolment, in all randomly allocated participants who had primary outcome data. The primary safety endpoint was procedural

  9. Assessment of carotid plaque composition using fast-kV switching dual-energy CT with gemstone detector: comparison with extracorporeal and virtual histology-intravascular ultrasound

    Energy Technology Data Exchange (ETDEWEB)

    Shinohara, Yuki; Kuya, Keita; Ohta, Yasutoshi; Fujii, Shinya; Ogawa, Toshihide [Tottori University, Division of Radiology, Department of Pathophysiological and Therapeutic Science, Faculty of Medicine, Yonago (Japan); Sakamoto, Makoto; Watanabe, Takashi [Tottori University, Division of Neurosurgery, Department of Neurological Sciences, Faculty of Medicine, Yonago (Japan); Kishimoto, Junichi; Iwata, Naoki [Tottori University Hospital, Division of Clinical Radiology, Yonago (Japan)

    2015-09-15

    The present study compares the applicability of CT carotid plaque imaging using effective Z maps using gemstone spectral imaging (GSI) with that of conventional extracorporeal carotid ultrasound (US) and virtual histology-intravascular ultrasound (VH-IVUS). We assessed stenosis in 31 carotid arteries of 30 patients. All patients underwent carotid CTA using GSI (Discovery CT750 HD, GE Healthcare). US and IVUS were examined with 25 and 8 vessels, respectively. We compared the effective Z values at noncalcified carotid plaque with the plaque components identified by US. We defined the plaque with low or low to iso intensity on US as vulnerable plaque and the plaque with iso, iso to high, and high intensity on US as stable plaque. We also performed visual assessment of color-coded effective Z maps in comparison with VH-IVUS and compared effective Z values with plaque components generated by VH-IVUS. The effective Z values at noncalcified carotid plaque were significantly lower for a group with vulnerable plaque, than with stable plaque on US (p < 0.05). Receiver operating curve analysis showed that AUC of effective Z values was 0.882 concerning the differentiation of these two groups on US. The interpretation of color-coded effective Z maps was essentially compatible with that of VH-IVUS for carotid plaque in all vessels. Effective Z values at noncalcified plaque showed significant negative correlation with the areas of fibro-fatty components generated by VH-IVUS (ρ = -0.874, p < 0.05). Effective Z maps generated by GSI can detect vulnerable carotid plaque materials. (orig.)

  10. Measurement of ventricular function using Doppler ultrasound

    International Nuclear Information System (INIS)

    Teague, S.M.

    1986-01-01

    Doppler has wide application in the evaluation of valvular heart disease. The need to know ventricular function is a much more common reason for an echocardiographic evaluation. Interestingly, Doppler examinations can assess ventricular function from many perspectives. Description of ventricular function entails measurement of the timing, rate and volume of ventricular filling and ejection. Doppler ultrasound examination reveals all of these aspects of ventricular function noninvasively, simply, and without great expense or radiation exposure, as described in this chapter

  11. PCA-based polling strategy in machine learning framework for coronary artery disease risk assessment in intravascular ultrasound: A link between carotid and coronary grayscale plaque morphology.

    Science.gov (United States)

    Araki, Tadashi; Ikeda, Nobutaka; Shukla, Devarshi; Jain, Pankaj K; Londhe, Narendra D; Shrivastava, Vimal K; Banchhor, Sumit K; Saba, Luca; Nicolaides, Andrew; Shafique, Shoaib; Laird, John R; Suri, Jasjit S

    2016-05-01

    Percutaneous coronary interventional procedures need advance planning prior to stenting or an endarterectomy. Cardiologists use intravascular ultrasound (IVUS) for screening, risk assessment and stratification of coronary artery disease (CAD). We hypothesize that plaque components are vulnerable to rupture due to plaque progression. Currently, there are no standard grayscale IVUS tools for risk assessment of plaque rupture. This paper presents a novel strategy for risk stratification based on plaque morphology embedded with principal component analysis (PCA) for plaque feature dimensionality reduction and dominant feature selection technique. The risk assessment utilizes 56 grayscale coronary features in a machine learning framework while linking information from carotid and coronary plaque burdens due to their common genetic makeup. This system consists of a machine learning paradigm which uses a support vector machine (SVM) combined with PCA for optimal and dominant coronary artery morphological feature extraction. Carotid artery proven intima-media thickness (cIMT) biomarker is adapted as a gold standard during the training phase of the machine learning system. For the performance evaluation, K-fold cross validation protocol is adapted with 20 trials per fold. For choosing the dominant features out of the 56 grayscale features, a polling strategy of PCA is adapted where the original value of the features is unaltered. Different protocols are designed for establishing the stability and reliability criteria of the coronary risk assessment system (cRAS). Using the PCA-based machine learning paradigm and cross-validation protocol, a classification accuracy of 98.43% (AUC 0.98) with K=10 folds using an SVM radial basis function (RBF) kernel was achieved. A reliability index of 97.32% and machine learning stability criteria of 5% were met for the cRAS. This is the first Computer aided design (CADx) system of its kind that is able to demonstrate the ability of coronary

  12. Mechanisms and Patterns of Intravascular Ultrasound In-Stent Restenosis Among Bare Metal Stents and First- and Second-Generation Drug-Eluting Stents.

    Science.gov (United States)

    Goto, Kosaku; Zhao, Zhijing; Matsumura, Mitsuaki; Dohi, Tomotaka; Kobayashi, Nobuaki; Kirtane, Ajay J; Rabbani, LeRoy E; Collins, Michael B; Parikh, Manish A; Kodali, Susheel K; Leon, Martin B; Moses, Jeffrey W; Mintz, Gary S; Maehara, Akiko

    2015-11-01

    The most common causes of in-stent restenosis (ISR) are intimal hyperplasia and stent under expansion. The purpose of this study was to use intravascular ultrasound (IVUS) to compare the ISR mechanisms of bare metal stents (BMS), first-generation drug-eluting stents (DES), and second-generation DES. There were 298 ISR lesions including 52 BMS, 73 sirolimus-eluting stents, 52 paclitaxel-eluting stents, 16 zotarolimus-eluting stents, and 105 everolimus-eluting stent. Mean patient age was 66.6 ± 1.1 years, 74.2% were men, and 48.3% had diabetes mellitus. BMS restenosis presented later (70.0 ± 66.7 months) with more intimal hyperplasia compared with DES (BMS 58.6 ± 15.5%, first-generation DES 52.6 ± 20.9%, second-generation DES 48.2 ± 22.2%, p = 0.02). Although reference lumen areas were similar in BMS and first- and second-generation DES, restenotic DES were longer (BMS 21.8 ± 13.5 mm, first-generation DES 29.4 ± 16.1 mm, second-generation DES 32.1 ± 18.7 mm, p = 0.003), and stent areas were smaller (BMS 7.2 ± 2.4 mm(2), first-generation DES 6.1 ± 2.1 mm(2), second-generation DES 5.7 ± 2.0 mm(2), p Stent fracture was seen only in DES (first-generation DES 7 [5.0%], second-generation DES 8 [7.4%], p = 0.13). In conclusion, restenotic first- and second-generation DES were characterized by less neointimal hyperplasia, smaller stent areas, longer stent lengths, and more stent fractures than restenotic BMS. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Influence of ezetimibe in addition to high-dose atorvastatin therapy on plaque composition in patients with ST-segment elevation myocardial infarction assessed by serial Intravascular ultrasound with iMap: the OCTIVUS trial*

    DEFF Research Database (Denmark)

    Hougaard, Mikkel; Hansen, Henrik Steen; Thayssen, Per

    2017-01-01

    Background: The aim of this study was to examine the influence of ezetimibe in addition to atorvastatin on plaque composition in patients with first-time ST-segment Elevation Myocardial Infarction treated with primary percutaneous intervention. Methods: Eighty-seven patients were randomized ( 1: 1......) to ezetimibe 10mg or placebo in addition to Atorvastatin 80 mg. Intravascular ultrasound with iMap was performed at baseline and after 12 months in a non-infarctrelated artery. Primary endpoint was change in necrotic core (NC). Secondary endpoints were total atheroma volume (TAV) and percentage atheroma volume.......3 +/- 9.4% to 42.2 +/- 10.7 p - 0.07),p - 0.91 between groups. Conclusions: Ezetimibe in addition to atorvastatin therapy did not influence NC content, but was associated with regression of coronary atherosclerosis. (C) 2016 Elsevier Inc. All rights reserved....

  14. Intimal hyperplasia and vascular remodeling after everolimus-eluting and sirolimus-eluting stent implantation in diabetic patients the randomized diabetes and drug-eluting stent (DiabeDES) IV intravascular ultrasound trial

    DEFF Research Database (Denmark)

    Antonsen, Lisbeth; Maeng, Michael; Thayssen, Per

    2013-01-01

    OBJECTIVE: To evaluate the effects of the everolimus-eluting Xience™/Promus™ stent (EES) and the sirolimus-eluting Cypher™ stent (SES) on intimal hyperplasia (IH) in diabetic patients. BACKGROUND: Patients with diabetes mellitus have increased risk of in-stent restenosis after coronary stent...... implantation due to intimal hyperplasia (IH). METHODS: In a sub study of the Randomized Comparison of Everolimus-Eluting and Sirolimus-Eluting Stents in Patients Treated with Percutaneous Coronary Intervention (SORT OUT IV trial), serial intravascular ultrasound (IVUS) 10-month follow-up data were available...... in 88 patients, including 48 EES and 40 SES treated patients. IVUS endpoints included IH volume, in-stent % volume obstruction and changes in external elastic membrane (EEM) volume. RESULTS: Compared with the SES group, IH volume was increased in the EES group [median (interquartile range): 2.8 mm(3) (0...

  15. Absence of accelerated atherosclerotic disease progression after intracoronary infusion of bone marrow derived mononuclear cells in patients with acute myocardial infarction--angiographic and intravascular ultrasound--results from the TErapia Celular Aplicada al Miocardio Pilot study.

    Science.gov (United States)

    Arnold, Roman; Villa, Adolfo; Gutiérrez, Hipólito; Sánchez, Pedro L; Gimeno, Federico; Fernández, Maria E; Gutiérrez, Oliver; Mota, Pedro; Sánchez, Ana; García-Frade, Javier; Fernández-Avilés, Francisco; San Román, Jose A

    2010-06-01

    We tried to evaluate a putative negative effect on coronary atherosclerosis in patients receiving intracoronary infusion of unfractionated bone marrow mononuclear cells (BMMC) following an acute ST-elevation myocardial infarction. Peripheral blood mononuclear cells or enriched CD133(+) BMMC have been associated with accelerated atherosclerosis of the distal segment of the infarct related artery (IRA). Thirty-seven patients with ST-elevation myocardial infarction from the TECAM pilot study underwent intracoronary infusion of autologous BMMC 9 +/- 3.1 days after onset of symptoms. We compared angiographic changes from baseline to 9 months of follow-up in the distal non-stented segment of the IRA, as well as in the contralateral coronary artery, with a matched control group. A subgroup of 15 treated patients underwent additional IVUS within the distal segment of the IRA. No difference between stem cell and control group were found regarding changes in minimum lumen diameter (0.006 +/- 0.42 vs 0.06 +/- 0.41 mm, P = ns) and the percentage of stenosis (-2.68 +/- 12.33% vs -1.78 +/- 8.75%, P = ns) at follow-up. Likewise, no differences were seen regarding changes in the contralateral artery (minimum lumen diameter -0.004 +/- 0.54 mm vs -0.06 +/- 0.35 mm, P = ns). In the intravascular ultrasound substudy, no changes were demonstrated comparing baseline versus follow-up in maximum area stenosis and plaque volume. In this pilot study, analysis of a subgroup of patients found that intracoronary injection of unfractionated BMMC in patients with acute ST-elevation myocardial infarction was not associated with accelerated atherosclerosis progression at mid term. Prospective, randomised studies in large cohorts with long-term angiographic and intravascular ultrasound follow-up are necessary to determine the safety of this therapy. Copyright 2010 Mosby, Inc. All rights reserved.

  16. A simple technique to measure regional cerebral blood flow during intravascular ballon clamping

    International Nuclear Information System (INIS)

    Furuhata, Shigeru; Kubo, Atsushi; Kawase, Takeshi; Ibata, Yukio; Toya, Shigeo

    1988-01-01

    A case of giant internal carotid ophthalmic aneurysm was presented. In order to clarify whether the patient could tolerate carotid occlusion, a ballon clamping test was performed before surgery. The cerebral blood flow was measured using early imaging by single photon emission computed tomography (SPECT) with N-isopropyl-(iodine-123)-p-iodoamphetamine ( 123 I-IMP). When the ballon clamping test was performed the tracer was injected, and scanning was performed 35 minutes after removing the catheter. This tracer enabled a 'memory of blood flow' during temporary ischemia to determine the character of quick diffusion and slow wash out, that could not be performed by other methods of cerebral blood flow measurement. SPECT with 123 I-IMP can simplify the measurement of cerebral blood flow during the balloon clamping test. (author)

  17. A numerical study on the influence of vulnerable plaque composition on intravascular thermography measurements

    International Nuclear Information System (INIS)

    Have, A G ten; Gijsen, F J H; Wentzel, J J; Slager, C J; Serruys, P W; Steen, A F W van der

    2006-01-01

    Intracoronary thermography is a technique that measures lumen wall temperatures for vulnerable plaque detection. In this paper the influence of vulnerable plaque composition on lumen wall temperatures was studied numerically. Concerning the vulnerable plaque heat generation, the location of the heat source and its heat production were varied. Concerning the heat transfer, the thermal properties of the lipid core and the location of the vasa vasorum were studied. The heat source location was the main determinant of the lumen wall temperature distribution. The strongest effect was noted when the heat producing macrophages were located in the shoulder region leading to focal spots of higher temperature. The maximal lumen wall temperature was mainly determined by the heat production of the macrophages and the cooling effect of blood. The insulating properties of the lipid core increased lumen wall temperatures when the heat source was located in the cap and the presence of vasa vasorum lowered the temperatures. These results show that the lumen wall temperature distribution is influenced by vulnerable plaque composition and that intracoronary thermography techniques require a high spatial resolution. To be able to couple temperature measurements to plaque vulnerability, intracoronary thermography needs to be combined with an imaging modality

  18. Automated measurement of stent strut coverage in intravascular optical coherence tomography

    Science.gov (United States)

    Ahn, Chi Young; Kim, Byeong-Keuk; Hong, Myeong-Ki; Jang, Yangsoo; Heo, Jung; Joo, Chulmin; Seo, Jin Keun

    2015-02-01

    Optical coherence tomography (OCT) is a non-invasive, cross-sectional imaging modality that has become a prominent imaging method in percutaneous intracoronary intervention. We present an automated detection algorithm for stent strut coordinates and coverage in OCT images. The algorithm for stent strut detection is composed of a coordinate transformation from the polar to the Cartesian domains and application of second derivative operators in the radial and the circumferential directions. Local region-based active contouring was employed to detect lumen boundaries. We applied the method to the OCT pullback images acquired from human patients in vivo to quantitatively measure stent strut coverage. The validation studies against manual expert assessments demonstrated high Pearson's coefficients ( R = 0.99) in terms of the stent strut coordinates, with no significant bias. An averaged Hausdorff distance of < 120 μm was obtained for vessel border detection. Quantitative comparison in stent strut to vessel wall distance found a bias of < 12.3 μm and a 95% confidence of < 110 μm.

  19. Is the inferior vena cava diameter measured by bedside ultrasonography valuable in estimating the intravascular volume in patients with septic shock?

    Directory of Open Access Journals (Sweden)

    Mortaza Talebi Doluie

    2016-07-01

    Full Text Available Introduction:Resuscitation should be initiated immediately in shock. Early goal-directed therapy is an established algorithm for the resuscitation in septic shock. The first step is to maintain cardiac preload. Central venous pressure (CVP plays an important role in goal-directed therapy. Central venous catheterization is invasive and time-consuming in emergency conditions. There are some alternative and noninvasive methods for estimating the intravascular volume such as measuring the inferior vena cava (IVC diameter by ultrasonography. Methods: We searched PubMed, Google scholar, and Scopus databases with keywords (central venous pressure OR venous pressure OR CVP AND (ultrasonography OR sonography AND (sepsis OR septic shock AND (inferior vena cava OR IVC.Result: The search resulted in 2550 articles. The articles were appraised regarding the relevance, type of article, and statistical methods. Finally, 12 articles were selected. The number of patients was between 30 and 83 cases (mean age=57-67 years, intubated and non-intubated in each study. The IVC diameter was measured in respiratory cycle by bedside ultrasonography in longitudinal subxiphoid view and caval index was calculated, then they were compared with the CVP measured by central venous catheter.Discussion: CVP is an indicator of intravascular fluid status and right heart function. CVP measurement is an invasive method and of course with some complications. The IVC is the biggest vein of venous system with low-pressure; expansion of the vein reflects intravascular volume.Conclusion: It seems that IVC diameter measured by ultrasonography could be used as an alternative method for the determination of CVP in the emergency or critical patients.

  20. Comparative evaluation of ultrasound scanner accuracy in distance measurement

    Science.gov (United States)

    Branca, F. P.; Sciuto, S. A.; Scorza, A.

    2012-10-01

    The aim of the present study is to develop and compare two different automatic methods for accuracy evaluation in ultrasound phantom measurements on B-mode images: both of them give as a result the relative error e between measured distances, performed by 14 brand new ultrasound medical scanners, and nominal distances, among nylon wires embedded in a reference test object. The first method is based on a least squares estimation, while the second one applies the mean value of the same distance evaluated at different locations in ultrasound image (same distance method). Results for both of them are proposed and explained.

  1. Measurement of ultrasound power using a calorimeter

    Science.gov (United States)

    Morgado, G.; Miqueleti, S.; Costa-Felix, R. P. B.

    2018-03-01

    This paper presents a comparison between the ultrasound power of a 1 MHz therapy equipment on the water using a calorimeter and a radiation force balance. For a range of 5 to 10 W, the results presented a normalized error less than 1, disclosing compatibility of the results from the developed system and the radiation force balance. The calorimetric method might be used as a faster and cheaper means for the verification of the ultrasonic power emitted by an equipment for physiotherapeutic treatment.

  2. Ultrasound as an Outcome Measure in Gout. A Validation Process by the OMERACT Ultrasound Working Group

    DEFF Research Database (Denmark)

    Terslev, Lene; Gutierrez, Marwin; Schmidt, Wolfgang A

    2015-01-01

    OBJECTIVE: To summarize the work performed by the Outcome Measures in Rheumatology (OMERACT) Ultrasound (US) Working Group on the validation of US as a potential outcome measure in gout. METHODS: Based on the lack of definitions, highlighted in a recent literature review on US as an outcome tool...

  3. Assessing intravascular fluid status

    African Journals Online (AJOL)

    The assessment of intravascular fluid volume is a difficult undertaking in both the intensive care unit and theatre situation ... equally applicable to pulmonary capillary wedge pressure. .... airway pressure, the more difficult it becomes to interpret ...

  4. Disseminated intravascular coagulation (DIC)

    Science.gov (United States)

    ... Jr, Silberstein LE, et al, eds. Hematology: Basic Principles and Practice . 6th ed. Philadelphia, PA: Elsevier Saunders; 2013:chap 141. Thachil J, Toh CH. Current concepts in the management of disseminated intravascular coagulation. Thromb Res . 2012;129 ...

  5. Intra-stent tissue evaluation within bare metal and drug-eluting stents > 3 years since implantation in patients with mild to moderate neointimal proliferation using optical coherence tomography and virtual histology intravascular ultrasound.

    Science.gov (United States)

    Kitabata, Hironori; Loh, Joshua P; Pendyala, Lakshmana K; Omar, Alfazir; Ota, Hideaki; Minha, Sa'ar; Magalhaes, Marco A; Torguson, Rebecca; Chen, Fang; Satler, Lowell F; Pichard, Augusto D; Waksman, Ron

    2014-04-01

    We aimed to compare neointimal tissue characteristics between bare-metal stents (BMS) and drug-eluting stents (DES) at long-term follow-up using optical coherence tomography (OCT) and virtual histology intravascular ultrasound (VH-IVUS). Neoatherosclerosis in neointima has been reported in BMS and in DES. Thirty patients with 36 stented lesions [BMS (n=17) or DES (n=19)] >3years after implantation were prospectively enrolled. OCT and VH-IVUS were performed and analyzed independently. Stents with ≥70% diameter stenosis were excluded. The median duration from implantation was 126.0months in the BMS group and 60.0months in the DES group (p 3years to stents had evidence of intimal disruption. The percentage volume of necrotic core (16.1% [9.7, 20.3] vs. 9.7% [7.0, 16.5], p=0.062) and dense calcium (9.5% [3.8, 13.6] vs. 2.7% [0.4, 4.9], p=0.080) in neointima tended to be greater in BMS-treated lesions. Intra-stent VH-TCFA (BMS vs. DES 45.5% vs. 18.2%, p=0.361) did not differ significantly. At long-term follow-up beyond 3 years after implantation, the intra-stent neointimal tissue characteristics appeared similar for both BMS and DES. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. Serial intravascular ultrasound analysis of peri-stent remodeling and proximal and distal edge effects after sirolimus-eluting or paclitaxel-eluting stent implantation in patients with diabetes mellitus

    DEFF Research Database (Denmark)

    Jensen, Lisette Okkels; Maeng, Michael; Mintz, Gary S

    2009-01-01

    Patients with diabetes have an increased risk of in-stent restenosis after coronary stent implantation. Serial intravascular ultrasound was used to study chronic arterial responses and edge effects after implantation of Cypher (Cordis, Johnson & Johnson, Miami Lakes, Florida) or Taxus (Boston......-up. The increase in peri-stent external elastic membrane (EEM) volume was more pronounced in the Taxus group (292.4 +/- 132.6 to 309.5 +/- 146.8 mm(3)) than in the Cypher group (274.4 +/- 137.2 to 275.4 +/- 140.1 mm(3); p = 0.005). Peri-stent plaque volume increased in the Taxus group (152.5 +/- 73.7 to 166.......1 +/- 85.1 mm(3)), but was unchanged in the Cypher group (153.5 +/- 75.5 to 151.5 +/- 75.8 mm(3); p = 0.002). In proximal and distal reference segments, mean lumen area decreased within the entire 5-mm edge segment (proximal and distal) because of plaque progression (distal, 5.5 +/- 3.6 to 5.8 +/- 3.7 mm(2...

  7. Intravascular ultrasound guidance to minimize the use of iodine contrast in percutaneous coronary intervention: the MOZART (Minimizing cOntrast utiliZation With IVUS Guidance in coRonary angioplasTy) randomized controlled trial.

    Science.gov (United States)

    Mariani, José; Guedes, Cristiano; Soares, Paulo; Zalc, Silvio; Campos, Carlos M; Lopes, Augusto C; Spadaro, André G; Perin, Marco A; Filho, Antonio Esteves; Takimura, Celso K; Ribeiro, Expedito; Kalil-Filho, Roberto; Edelman, Elazer R; Serruys, Patrick W; Lemos, Pedro A

    2014-11-01

    The aim of this study was to evaluate the impact of intravascular ultrasound (IVUS) guidance on the final volume of contrast agent used in patients undergoing percutaneous coronary intervention (PCI). To date, few approaches have been described to reduce the final dose of contrast agent in PCIs. We hypothesized that IVUS might serve as an alternative imaging tool to angiography in many steps during PCI, thereby reducing the use of iodine contrast. A total of 83 patients were randomized to angiography-guided PCI or IVUS-guided PCI; both groups were treated according to a pre-defined meticulous procedural strategy. The primary endpoint was the total volume contrast agent used during PCI. Patients were followed clinically for an average of 4 months. The median total volume of contrast was 64.5 ml (interquartile range [IQR]: 42.8 to 97.0 ml; minimum, 19 ml; maximum, 170 ml) in the angiography-guided group versus 20.0 ml (IQR: 12.5 to 30.0 ml; minimum, 3 ml; maximum, 54 ml) in the IVUS-guided group (p MOZART]; NCT01947335). Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  8. Intravascular malignant lymphomatosis

    International Nuclear Information System (INIS)

    Martin-Duverneuil, N.; Lafitte, F.; Chiras, J.; Mokhtari, K.; Behin, A.; Hoang-Xuan, K.

    2002-01-01

    Intravascular malignant lymphomatosis is a rare and probably often overlooked disease characterised by massive intravascular proliferation of lymphoid cells, usually with a poor prognosis. CT and MRI appearances are nonspecific; the most suggestive finding being both asymmetrical, bilateral, contrast enhancing high-signal areas on T2 weighting and infarct-like lesions of the cortex and basal ganglia. We report two patients with previously unreported dural and spinal cord involvement. (orig.)

  9. Intravascular malignant lymphomatosis

    Energy Technology Data Exchange (ETDEWEB)

    Martin-Duverneuil, N.; Lafitte, F.; Chiras, J. [Service de Neuroradiologie Charcot, Batiment Babinski, Hopital de la Salpetriere, 75013 Paris (France); Mokhtari, K. [Service de Neuropathologie, Hopital de la Salpetriere, 75013 Paris (France); Behin, A.; Hoang-Xuan, K. [Departement de Neurologie, Hopital de la Salpetriere, 75013 Paris (France)

    2002-09-01

    Intravascular malignant lymphomatosis is a rare and probably often overlooked disease characterised by massive intravascular proliferation of lymphoid cells, usually with a poor prognosis. CT and MRI appearances are nonspecific; the most suggestive finding being both asymmetrical, bilateral, contrast enhancing high-signal areas on T2 weighting and infarct-like lesions of the cortex and basal ganglia. We report two patients with previously unreported dural and spinal cord involvement. (orig.)

  10. Ultrasound

    Science.gov (United States)

    Ultrasound is a useful procedure for monitoring the baby's development in the uterus. Ultrasound uses inaudible sound waves to produce a two-dimensional image of the baby while inside the mother's ...

  11. Validation of Navigation Ultrasound for Clavicular Length Measurement

    DEFF Research Database (Denmark)

    Høj, Anders Thorsmark; Villa, Chiara; Christensen, Ole M.

    2017-01-01

    interval): approximately ± 7.5 mm, Pearson's correlation R: 0.948-0.974). Navigation ultrasound can measure clavicular length with an intra-rater reliability matching that of 3-D rendered computed tomography scans and with high validity. Its use could spread to other fields requiring accurate...... of 52.5 (range: 21-78 y) were included. Navigation ultrasound exhibited high reliability (intra-class correlation coefficient: 0.942-0.997, standard error of the mean: 0.7-2.9 mm, minimal detectable change: 2.3-8.1 mm) and validity (measurement error: 1.3%-1.8%, limits of agreement (95% confidence...

  12. Intravascular pulmonary metastases

    International Nuclear Information System (INIS)

    Shepard, J.A.O.; Moore, E.H.; Templeton, P.A.; McLoud, T.C.

    1988-01-01

    The diagnosis of intravascular metastatic tumor emboli to the lungs is rarely made. The authors present a characteristic radiographic finding of intravascular lung metastases that they observed in four patients with diagnoses or right atrial myoxoma, invasive renal cell carcinoma, invasive pelvic osteosarcoma, and recurrent pelvic chondrosarcoma. Substantiation of intravascular pulmonary metastases was achieved by means of autopsy, pulmonary artery biopsy, and surgical documentation of tumor invasion of the inferior vena cava or pelvic veins. In all four cases, chest computed tomography (CT) demonstrated branching, beaded opacities extending from the hila into the periphery of the lung in the distribution of pulmonary arteries. In one case, similar findings were observed in magnetic resonance (MR) images of the chest. Follow-up studies in three cases showed progressive enlargement and varicosity of the abnormal pulmonary artery consistent with proliferation of intravascular tumor. In the case of metastatic osteosarcoma, intraluminal ossification was also observed at CT. In three of four cases, pulmonary infarction was demonstrated in the distribution of the abnormal pulmonary arteries seen at CT as small, peripheral, wedge-shaped opacities. The demonstration of progressively dilated and beaded pulmonary arteries in patients with extrathoracic malignancies is suggestive of intravascular lung metastases, particularly when accompanied by peripheral infarction

  13. Cintilografia do miocárdio com tecnécio 99m-MIBI e administração de adenosina em portadores de doença arterial coronária: correlação dos resultados com a angiografia coronária e o ultra-som intracoronário Adenosine myocardial perfusion SPECT with Tc-99m-MIBI in patients with obstructive coronary artery disease: correlation between quantitative coronary angiography and intravascular ultrasound measurements

    Directory of Open Access Journals (Sweden)

    Luiz Eduardo Mastrocolla

    2006-01-01

    Full Text Available OBJETIVO: Estabelecer a correlação da cintilografia de perfusão do miocárdio (CPM com Tecnécio 99m-MIBI (MIBI e injeção de adenosina, empregando a angiografia coronária quantitativa (ACQ e o ultra-som intracoronário (UIC como comparação. MÉTODOS: Estudo de 70 pacientes com doença arterial coronária (DAC, encaminhados à CPM com MIBI e adenosina. As manifestações clínicas, do eletrocardiograma (ECG e os resultados das imagens foram correlacionadas às variáveis da análise visual e quantitativa da angiografia, bem como ao UIC. RESULTADOS: A média de idades foi de 60,6 anos, com 39 pacientes do sexo masculino. A angiografia coronária evidenciou estenose do diâmetro da luz (E% de 49,94% em 105 artérias, com reavaliação à ACQ em 83 artérias (79% e média de 44,20%, pOBJECTIVE: To correlate myocardial perfusion scintigraphy (MPS with Tc-99m-MIBI and adenosine infusion using quantitative coronary angiography (QCA and intravascular ultrasound (IVUS. METHODS: Seventy patients with coronary artery disease (CAD referred for myocardial perfusion scintigraphy (MPS with MIBI and adenosine were studied. Clinical, electrocardiographic (ECG, and scintigraphic findings were correlated with variables of visual and quantitative angiographic analysis, as well as to those of IVUS. RESULTS: The mean age of patients was 60.6 years, and 39 were male. Coronary angiography showed percentage of diameter stenosis (% DS of 49.94% in 105 arteries, 83 of which were re-evaluated by QCA (79%, mean of 44.20%, p<0.05. ST-segment depression during adenosine infusion was associated with higher degrees of % DS (55.0% vs. 47.8%, p<0.05. Scintigraphic ischemia was correlated with greater cross-sectional area of lumen obstruction by IVUS (% CSA. Clinical, ECG, and IVUS findings were considered together and expressed as global ischemic versus non-ischemic responses. Ischemia was associated with lower values of minimal lumen diameter (MLD and minimal lumen area

  14. Ultrasound measurements of testicular volume: Comparing the three ...

    African Journals Online (AJOL)

    T.U. Mbaeri

    The ultrasound measurements of the testicular volume were calculated using the following three formulas: (a) length ... ticular growth, development and function. Studies in ... of the components of a minimum full evaluation of male infertility is palpation of ... opted for orchidectomy after counseling in our center. Subjects and ...

  15. Correlation between self-reported gestational age and ultrasound measurements

    DEFF Research Database (Denmark)

    Olesen, Annette Wind; Westergaard, Jes Grabow; Thomsen, Sten Grove

    2004-01-01

    BACKGROUND: We studied the agreement between different measurements of gestational age, i.e. self-reported gestational age in the Danish National Birth Cohort Study, ultrasound-estimated gestational age from the medical records in one Danish county and gestational age from the Danish National...

  16. Dosimetric model for intravascular brachytherapy

    International Nuclear Information System (INIS)

    Flower, E.E.; Stroud, D.B.

    2000-01-01

    Full text: Intravascular brachytherapy has been shown to be a prophylaxis for restenosis. Adventitial macrophages, which are extremely radiosensitive, initiate neointima formation. A model of the dose levels of the treatment range is developed, assuming that the adventitia is the target tissue. If the adventitia receives a dose of less than 10 Gy, it is assumed the treatment will be ineffective. If the dose to any part of the wall is above 30 Gy, it is assumed that the treatment could be detrimental. Hence the treatment range is between 10 and 30 Gy, with 20 Gy being the optimum dosage to the adventitia. An algorithm using numerical integration of published dose kernels calculates the dose at any point surrounding a beta ( 32 P) line source of finite length. Dose profiles were obtained to demonstrate edge effects. For long lesions, the source is often stepped along the artery. Dose changes due to separation or overlapping of sources during source stepping procedures were also determined. Isodose curves were superimposed on intravascular ultrasound images to demonstrate dose levels. For an exposure time of 60 seconds with a 200mCi source, the optimum dose of 20 Gy occurs at a distance 1.94mm from the centre of the source. The upper limit of the treatment dose range (30 Gy) occurs at 1.59mm. The lower limit of the treatment dose range (10 Gy) occurs at 2.7mm. Significant perturbations to the treatment dose range can be caused by non-centering of the source, edge effects and separation or overlapping of sources in stepping procedures. Despite these concerns, many successful procedures have been reported and this implies that the model is over simplified and requires modifications. Copyright (2000) Australasian College of Physical Scientists and Engineers in Medicine

  17. Intravascular Young's modulus reconstruction using a parametric finite element model

    NARCIS (Netherlands)

    Baldewsing, R.A.; Oomens, C.W.J.; Steen, van der A.F.W.; Yuhas, D.; Schneider, S.C.

    2003-01-01

    IntraVascular UltraSound (IVUS) elastography may be used to detect vulnerable, rupture prone plaques, which are held responsible for the majority of acute coronary syndromes. IVUS elastography accomplishes this by visualising local incremental radial strain of arteries, in so-called elastograms.

  18. Intravascular "mulberry-like" bodies

    DEFF Research Database (Denmark)

    Sørensen, Flemming Brandt; Klebe, J G; Henriques, U V

    1988-01-01

    Intravascular "mulberry-like" bodies in a stillborn female infant with moderate maceration are reported. The histogenesis of these structures is discussed based on light-microscopic, immunohistochemical and ultrastructural findings. No demonstrable causal relation between the intravascular lesion...... and fetal death was found, the cause of death being attributed to intrauterine asphyxia. It is concluded, that intravascular "mulberry-bodies" most likely represent artifacts due to red blood cell autolysis.......Intravascular "mulberry-like" bodies in a stillborn female infant with moderate maceration are reported. The histogenesis of these structures is discussed based on light-microscopic, immunohistochemical and ultrastructural findings. No demonstrable causal relation between the intravascular lesions...

  19. Comparison of Simulated and Measured Non-linear Ultrasound Fields

    DEFF Research Database (Denmark)

    Du, Yigang; Jensen, Henrik; Jensen, Jørgen Arendt

    2011-01-01

    In this paper results from a non-linear AS (angular spectrum) based ultrasound simulation program are compared to water-tank measurements. A circular concave transducer with a diameter of 1 inch (25.4 mm) is used as the emitting source. The measured pulses are rst compared with the linear...... simulation program Field II, which will be used to generate the source for the AS simulation. The generated non-linear ultrasound eld is measured by a hydrophone in the focal plane. The second harmonic component from the measurement is compared with the AS simulation, which is used to calculate both...... fundamental and second harmonic elds. The focused piston transducer with a center frequency of 5 MHz is excited by a waveform generator emitting a 6-cycle sine wave. The hydrophone is mounted in the focal plane 118 mm from the transducer. The point spread functions at the focal depth from Field II...

  20. Ultrasound transmission measurements for tensile strength evaluation of tablets.

    Science.gov (United States)

    Simonaho, Simo-Pekka; Takala, T Aleksi; Kuosmanen, Marko; Ketolainen, Jarkko

    2011-05-16

    Ultrasound transmission measurements were performed to evaluate the tensile strength of tablets. Tablets consisting of one ingredient were compressed from dibasic calcium phosphate dehydrate, two grades of microcrystalline cellulose and two grades of lactose monohydrate powders. From each powder, tablets with five different tensile strengths were directly compressed. Ultrasound transmission measurements were conducted on every tablet at frequencies of 2.25 MHz, 5 MHz and 10 MHz and the speed of sound was calculated from the acquired waveforms. The tensile strength of the tablets was determined using a diametrical mechanical testing machine and compared to the calculated speed of sound values. It was found that the speed of sound increased with the tensile strength for the tested excipients. There was a good correlation between the speed of sound and tensile strength. Moreover, based on the statistical tests, the groups with different tensile strengths can be differentiated from each other by measuring the speed of sound. Thus, the ultrasound transmission measurement technique is a potentially useful method for non-destructive and fast evaluation of the tensile strength of tablets. Copyright © 2011 Elsevier B.V. All rights reserved.

  1. HIFU Ultrasound Power Measurements at INRiM

    International Nuclear Information System (INIS)

    Durando, G; Guglielmone, C; Musacchio, C

    2011-01-01

    In this work the new system for the ultrasound power measurement of High Intensity Focused Ultrasound transducers realized at INRIM ultrasounds laboratory is presented. The system is based on a submersible load cell that takes the place of the balance. This solution presents essentially two advantages. The first one, of mechanical nature, is relevant to the fact that the target is directly connected to the force transducer, eliminating unwanted target motion at high power. The second, of electric nature, concerns the possibility to reduce the insonation time (the ON period of the electric driving signal to the HIFU transducer) under of 2 s, and is allowed for by the faster response of the force transducer (700 Hz bandwidth). The main components of uncertainty and the overall budget of the measurement system are presented together with the results of measures of conductance, G, carried on a HIFU transducer, at the work frequencies 2.0 MHz and 6.38 MHz, for values of power ranging from 10 W to 100 W. The results of the ultrasonic conductance, G, obtained with the new system are compared with values obtained using the traditional measuring system for low powers (P ≤ 20W).

  2. Non-Invasive Measurement of Intracranial Pressure Pulsation using Ultrasound

    Science.gov (United States)

    Ueno, Toshiaki; Ballard, R. E.; Yost, W. T.; Hargens, A. R.

    1997-01-01

    Exposure to microgravity causes a cephalad fluid shift which may elevate intracranial pressure (ICP). Elevation in ICP may affect cerebral hemodynamics in astronauts during space flight. ICP is, however, a difficult parameter to measure due to the invasiveness of currently available techniques. We already reported our development of a non-invasive ultrasound device for measurement of ICP. We recently modified the device so that we might reproducibly estimate ICP changes in association with cardiac cycles. In the first experiment, we measured changes in cranial distance with the ultrasound device in cadavera while changing ICP by infusing saline into the lateral ventricle. In the second experiment, we measured changes in cranial distance in five healthy volunteers while placing them in 60 deg, 30 deg head-up tilt, supine, and 10 deg head-down tilt position. In the cadaver study, fast Fourier transformation revealed that cranial pulsation is clearly associated with ICP pulsation. The ratio of cranial distance and ICP pulsation is 1.3microns/mmHg. In the tilting study, the magnitudes of cranial pulsation are linearly correlated to tilt angles (r=0.87). The ultrasound device has sufficient sensitivity to detect cranial pulsation in association with cardiac cycles. By analyzing the magnitude of cranial pulsation, estimates of ICP during space flight are possible.

  3. Augmentation of limb perfusion and reversal of tissue ischemia produced by ultrasound-mediated microbubble cavitation.

    Science.gov (United States)

    Belcik, J Todd; Mott, Brian H; Xie, Aris; Zhao, Yan; Kim, Sajeevani; Lindner, Nathan J; Ammi, Azzdine; Linden, Joel M; Lindner, Jonathan R

    2015-04-01

    Ultrasound can increase tissue blood flow, in part, through the intravascular shear produced by oscillatory pressure fluctuations. We hypothesized that ultrasound-mediated increases in perfusion can be augmented by microbubble contrast agents that undergo ultrasound-mediated cavitation and sought to characterize the biological mediators. Contrast ultrasound perfusion imaging of hindlimb skeletal muscle and femoral artery diameter measurement were performed in nonischemic mice after unilateral 10-minute exposure to intermittent ultrasound alone (mechanical index, 0.6 or 1.3) or ultrasound with lipid microbubbles (2×10(8) IV). Studies were also performed after inhibiting shear- or pressure-dependent vasodilator pathways, and in mice with hindlimb ischemia. Ultrasound alone produced a 2-fold increase (Pultrasound power. Ultrasound-mediated augmentation in flow was greater with microbubbles (3- and 10-fold higher than control for mechanical index 0.6 and 1.3, respectively; Pultrasound and microbubbles by 70% (Pultrasound and ultrasound with microbubbles. In mice with unilateral hindlimb ischemia (40%-50% reduction in flow), ultrasound (mechanical index, 1.3) with microbubbles increased perfusion by 2-fold to a degree that was greater than the control nonischemic limb. Increases in muscle blood flow during high-power ultrasound are markedly amplified by the intravascular presence of microbubbles and can reverse tissue ischemia. These effects are most likely mediated by cavitation-related increases in shear and activation of endothelial nitric oxide synthase. © 2015 American Heart Association, Inc.

  4. Air-coupled ultrasound for plate thickness measurements

    OpenAIRE

    Waag, Grunde

    2017-01-01

    Non-destructive testing using ultrasound is well established as a technique of inspecting miscellaneous structures and components. Ultrasonic waves propagating in an elastic solid are sensitive to both the material and geometrical properties of the solid. Decades of experience have shown that it is possible to extract these properties from the waves in an efficient and reliable way in a variety of practical measurement settings. Different techniques have been developed over many decades, and ...

  5. Intravascular (catheter) MR imaging

    International Nuclear Information System (INIS)

    Cohen, A.M.; Hurst, G.C.; Katz, D.E.; Dverk, J.L.; Wiesen, E.J.; Czerski, L.W.; Malaya, R.; Bellon, E.M.

    1989-01-01

    Intravascular MR probes allow excellent spatial resolution and have the potential to detect arterial wall microstructure. Ultrasonic intravascular probes suggest that detailed morphologic information can assist clinical decision making. Catheter MR probes of 2--7 mm outside diameter (OD) were built of copper wire, Teflon, and parts from standard commercial catheters. The probes were connected to the surface coil receiver input of our Picker VISTA 2055HP 1.5-T imaging system. The extant (linear) body coil was used for transmit. Phantoms were constructed of coaxial glass MR tubes, filled with doped water. Watanabe rabbit aorta and human autopsy iliac artery specimens were examined within 4 hours of excision or stored by freezing. In vivo iliac arteries in dogs under general anesthesia were imaged, with percutaneous placement of the probe. Results are presented

  6. Quantitative Measurements using Ultrasound Vector Flow Imaging

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt

    2016-01-01

    scanner for pulsating flow mimicking the femoral artery from a CompuFlow 1000 pump (Shelley Medical). Data were used in four estimators based on directional transverse oscillation for velocity, flow angle, volume flow, and turbulence estimation and their respective precisions. An adaptive lag scheme gave...... the ability to estimate a large velocity range, or alternatively measure at two sites to find e.g. stenosis degree in a vessel. The mean angle at the vessel center was estimated to 90.9◦±8.2◦ indicating a laminar flow from a turbulence index being close to zero (0.1 ±0.1). Volume flow was 1.29 ±0.26 mL/stroke...... (true: 1.15 mL/stroke, bias: 12.2%). Measurements down to 160 mm were obtained with a relative standard deviation and bias of less than 10% for the lateral component for stationary, parabolic flow. The method can, thus, find quantitative velocities, angles, and volume flows at sites currently...

  7. Dual-plane ultrasound flow measurements in liquid metals

    International Nuclear Information System (INIS)

    Büttner, Lars; Nauber, Richard; Burger, Markus; Czarske, Jürgen; Räbiger, Dirk; Franke, Sven; Eckert, Sven

    2013-01-01

    An ultrasound measurement system for dual-plane, two-component flow velocity measurements especially in opaque liquids is presented. Present-day techniques for measuring local flow structures in opaque liquids disclose considerable drawbacks concerning line-wise measurement of single ultrasound probes. For studying time-varying flow patterns, conventional ultrasound techniques are either limited by time-consuming mechanical traversing or by the sequential operation of single probes. The measurement system presented within this paper employs four transducer arrays with a total of 100 single elements which allows for flow mapping without mechanical traversing. A high frame rate of several 10 Hz has been achieved due to an efficient parallelization scheme using time-division multiplexing realized by a microcontroller-based electronic switching matrix. The functionality and capability of the measurement system are demonstrated on a liquid metal flow at room temperature inside a cube driven by a rotating magnetic field (RMF). For the first time, the primary and the secondary flow have been studied in detail and simultaneously using a configuration with two crossed measurement planes. The experimental data confirm predictions made by numeric simulation. After a sudden switching on of the RMF, inertial oscillations of the secondary flow were observed by means of a time-resolved measurement with a frame rate of 3.4 Hz. The experiments demonstrate that the presented measurement system is able to investigate complex and transient flow structures in opaque liquids. Due to its ability to study the temporal evolution of local flow structures, the measurement system could provide considerable progress for fluid dynamics research, in particular for applications in the food industry or liquid metal technologies. (paper)

  8. Dual-plane ultrasound flow measurements in liquid metals

    Science.gov (United States)

    Büttner, Lars; Nauber, Richard; Burger, Markus; Räbiger, Dirk; Franke, Sven; Eckert, Sven; Czarske, Jürgen

    2013-05-01

    An ultrasound measurement system for dual-plane, two-component flow velocity measurements especially in opaque liquids is presented. Present-day techniques for measuring local flow structures in opaque liquids disclose considerable drawbacks concerning line-wise measurement of single ultrasound probes. For studying time-varying flow patterns, conventional ultrasound techniques are either limited by time-consuming mechanical traversing or by the sequential operation of single probes. The measurement system presented within this paper employs four transducer arrays with a total of 100 single elements which allows for flow mapping without mechanical traversing. A high frame rate of several 10 Hz has been achieved due to an efficient parallelization scheme using time-division multiplexing realized by a microcontroller-based electronic switching matrix. The functionality and capability of the measurement system are demonstrated on a liquid metal flow at room temperature inside a cube driven by a rotating magnetic field (RMF). For the first time, the primary and the secondary flow have been studied in detail and simultaneously using a configuration with two crossed measurement planes. The experimental data confirm predictions made by numeric simulation. After a sudden switching on of the RMF, inertial oscillations of the secondary flow were observed by means of a time-resolved measurement with a frame rate of 3.4 Hz. The experiments demonstrate that the presented measurement system is able to investigate complex and transient flow structures in opaque liquids. Due to its ability to study the temporal evolution of local flow structures, the measurement system could provide considerable progress for fluid dynamics research, in particular for applications in the food industry or liquid metal technologies.

  9. Refining enamel thickness measurements from B-mode ultrasound images.

    Science.gov (United States)

    Hua, Jeremy; Chen, Ssu-Kuang; Kim, Yongmin

    2009-01-01

    Dental erosion has been growing increasingly prevalent with the rise in consumption of heavy starches, sugars, coffee, and acidic beverages. In addition, various disorders, such as Gastroenterological Reflux Disease (GERD), have symptoms of rapid rates of tooth erosion. The measurement of enamel thickness would be important for dentists to assess the progression of enamel loss from all forms of erosion, attrition, and abrasion. Characterizing enamel loss is currently done with various subjective indexes that can be interpreted in different ways by different dentists. Ultrasound has been utilized since the 1960s to determine internal tooth structure, but with mixed results. Via image processing and enhancement, we were able to refine B-mode dental ultrasound images for more accurate enamel thickness measurements. The mean difference between the measured thickness of the occlusal enamel from ultrasound images and corresponding gold standard CT images improved from 0.55 mm to 0.32 mm with image processing (p = 0.033). The difference also improved from 0.62 to 0.53 mm at the buccal/lingual enamel surfaces, but not significantly (p = 0.38).

  10. Ultrasound

    Science.gov (United States)

    ... completed. Young children may need additional preparation. When scheduling an ultrasound for yourself or your child, ask ... of Privacy Practices Notice of Nondiscrimination Manage Cookies Advertising Mayo Clinic is a not-for-profit organization ...

  11. Ultrasound

    Science.gov (United States)

    ... reflect off body structures. A computer receives the waves and uses them to create a picture. Unlike with an x-ray or CT scan, this test does not use ionizing radiation. The test is done in the ultrasound ...

  12. Intravascular "mulberry-like" bodies

    DEFF Research Database (Denmark)

    Sørensen, Flemming Brandt; Klebe, J G; Henriques, U V

    1988-01-01

    Intravascular "mulberry-like" bodies in a stillborn female infant with moderate maceration are reported. The histogenesis of these structures is discussed based on light-microscopic, immunohistochemical and ultrastructural findings. No demonstrable causal relation between the intravascular lesions...... and fetal death was found, the cause of death being attributed to intrauterine asphyxia. It is concluded, that intravascular "mulberry-bodies" most likely represent artifacts due to red blood cell autolysis....

  13. Metatarsophalangeal joint extension changes ultrasound measurements for plantar fascia thickness.

    Science.gov (United States)

    Granado, Michael J; Lohman, Everett B; Gordon, Keith E; Daher, Noha S

    2018-01-01

    Ultrasound is an inexpensive method for quantifying plantar fascia thickness, especially in those with plantar fasciitis. Ultrasound has also been used to assess the effectiveness of various treatments for plantar fasciitis by comparing plantar fascia thickness before and after an intervention period. While a plantar fascia thickness over 4 mm via ultrasound has been proposed to be consistent with plantar fasciitis, some researchers believe the 4 mm plantar fascia thickness level to be a dubious guideline for diagnosing plantar fasciitis due to the lack of standardization of the measurement process for plantar fascia thickness. In particular, no universal guidelines exist on the positioning of the metatarsophalangeal (MTP) joints during the procedure and the literature also has inconsistent protocols. The purpose of this study is to investigate and compare the influence of MTP joint extension on plantar fascia thickness in healthy participants and those with unilateral plantar fasciitis. The plantar fascia thickness of forty participants (20 with unilateral plantar fasciitis and 20 control) was measured via ultrasound three times at three different MTP joint positions: 1) at rest, 2) 30° of extension from the plantar surface, and 3) maximal extension possible. The plantar fascia became significantly thinner as MTP joint extension increased in both the plantar fasciitis group ( p  plantar fasciitis group, the involved plantar fascia was 1.2 to 1.3 mm thicker (p plantar fascia thickness between the two sides was less than 0.1 mm ( p  plantar fascia thickness. It is recommended that plantar fascia thickness measurements be performed with the toes at rest. If MTP joints must be extended, then the toes should be extended maximally and then noted to ensure subsequent ultrasound procedures are repeated. Standardizing the position of the MTP joints is not only important for attaining the most accurate thickness measurement of the plantar fascia, but is also

  14. Ability of combined Near-Infrared Spectroscopy-Intravascular Ultrasound (NIRS-IVUS) imaging to detect lipid core plaques and estimate cap thickness in human autopsy coronary arteries

    Science.gov (United States)

    Grainger, S. J.; Su, J. L.; Greiner, C. A.; Saybolt, M. D.; Wilensky, R. L.; Raichlen, J. S.; Madden, S. P.; Muller, J. E.

    2016-03-01

    The ability to determine plaque cap thickness during catheterization is thought to be of clinical importance for plaque vulnerability assessment. While methods to compositionally assess cap integrity are in development, a method utilizing currently available tools to measure cap thickness is highly desirable. NIRS-IVUS is a commercially available dual imaging method in current clinical use that may provide cap thickness information to the skilled reader; however, this is as yet unproven. Ten autopsy hearts (n=15 arterial segments) were scanned with the multimodality NIRS-IVUS catheter (TVC Imaging System, Infraredx, Inc.) to identify lipid core plaques (LCPs). Skilled readers made predictions of cap thickness over regions of chemogram LCP, using NIRS-IVUS. Artery segments were perfusion fixed and cut into 2 mm serial blocks. Thin sections stained with Movat's pentachrome were analyzed for cap thickness at LCP regions. Block level predictions were compared to histology, as classified by a blinded pathologist. Within 15 arterial segments, 117 chemogram blocks were found by NIRS to contain LCP. Utilizing NIRSIVUS, chemogram blocks were divided into 4 categories: thin capped fibroatheromas (TCFA), thick capped fibroatheromas (ThCFA), pathological intimal thickening (PIT)/lipid pool (no defined cap), and calcified/unable to determine cap thickness. Sensitivities/specificities for thin cap fibroatheromas, thick cap fibroatheromas, and PIT/lipid pools were 0.54/0.99, 0.68/0.88, and 0.80/0.97, respectively. The overall accuracy rate was 70.1% (including 22 blocks unable to predict, p = 0.075). In the absence of calcium, NIRS-IVUS imaging provided predictions of cap thickness over LCP with moderate accuracy. The ability of this multimodality imaging method to identify vulnerable coronary plaques requires further assessment in both larger autopsy studies, and clinical studies in patients undergoing NIRS-IVUS imaging.

  15. Statistical shape modeling based renal volume measurement using tracked ultrasound

    Science.gov (United States)

    Pai Raikar, Vipul; Kwartowitz, David M.

    2017-03-01

    Autosomal dominant polycystic kidney disease (ADPKD) is the fourth most common cause of kidney transplant worldwide accounting for 7-10% of all cases. Although ADPKD usually progresses over many decades, accurate risk prediction is an important task.1 Identifying patients with progressive disease is vital to providing new treatments being developed and enable them to enter clinical trials for new therapy. Among other factors, total kidney volume (TKV) is a major biomarker predicting the progression of ADPKD. Consortium for Radiologic Imaging Studies in Polycystic Kidney Disease (CRISP)2 have shown that TKV is an early, and accurate measure of cystic burden and likely growth rate. It is strongly associated with loss of renal function.3 While ultrasound (US) has proven as an excellent tool for diagnosing the disease; monitoring short-term changes using ultrasound has been shown to not be accurate. This is attributed to high operator variability and reproducibility as compared to tomographic modalities such as CT and MR (Gold standard). Ultrasound has emerged as one of the standout modality for intra-procedural imaging and with methods for spatial localization has afforded us the ability to track 2D ultrasound in physical space which it is being used. In addition to this, the vast amount of recorded tomographic data can be used to generate statistical shape models that allow us to extract clinical value from archived image sets. In this work, we aim at improving the prognostic value of US in managing ADPKD by assessing the accuracy of using statistical shape model augmented US data, to predict TKV, with the end goal of monitoring short-term changes.

  16. Measurement of Angle Kappa Using Ultrasound Biomicroscopy and Corneal Topography.

    Science.gov (United States)

    Yeo, Joon Hyung; Moon, Nam Ju; Lee, Jeong Kyu

    2017-06-01

    To introduce a new convenient and accurate method to measure the angle kappa using ultrasound biomicroscopy (UBM) and corneal topography. Data from 42 eyes (13 males and 29 females) were analyzed in this study. The angle kappa was measured using Orbscan II and calculated with UBM and corneal topography. The angle kappa of the dominant eye was compared with measurements by Orbscan II. The mean patient age was 36.4 ± 13.8 years. The average angle kappa measured by Orbscan II was 3.98° ± 1.12°, while the average angle kappa calculated with UBM and corneal topography was 3.19° ± 1.15°. The difference in angle kappa measured by the two methods was statistically significant (p topography to calculate the angle kappa. This method is convenient to use and allows for measurement of the angle kappa without an expensive device. © 2017 The Korean Ophthalmological Society

  17. Assessment of performance measures and learning curves for use of a virtual-reality ultrasound simulator in transvaginal ultrasound examination

    DEFF Research Database (Denmark)

    Madsen, M E; Konge, L; Nørgaard, L N

    2014-01-01

    OBJECTIVE: To assess the validity and reliability of performance measures, develop credible performance standards and explore learning curves for a virtual-reality simulator designed for transvaginal gynecological ultrasound examination. METHODS: A group of 16 ultrasound novices, along with a group......-6), corresponding to an average of 219 min (range, 150-251 min) of training. The test/retest reliability was high, with an intraclass correlation coefficient of 0.93. CONCLUSIONS: Competence in the performance of gynecological ultrasound examination can be assessed in a valid and reliable way using virtual-reality...

  18. Ultrasound measurement of transcranial distance during head-down tilt

    Science.gov (United States)

    Torikoshi, S.; Wilson, M. H.; Ballard, R. E.; Watenpaugh, D. E.; Murthy, G.; Yost, W. T.; Cantrell, J. H.; Chang, D. S.; Hargens, A. R.

    1995-01-01

    Exposure to microgravity elevates blood pressure and flow in the head, which may increase intracranial volume (ICV) and intracranial pressure (ICP). Rhesus monkeys exposed to simulated microgravity in the form of 6 degree head-down tilt (HDT) experience elevated ICP. With humans, twenty-four hours of 6 degree HDT bed rest increases cerebral blood flow velocity relative to pre-HDT upright posture. Humans exposed to acute 6 degree HDT experiments increased ICP, measured with the tympanic membrane displacement (TMD) technique. Other studies suggest that increased ICP in humans and cats causes measurable cranial bone movement across the sagittal suture. Due to the slightly compliant nature of the cranium, elevation of the ICP will increase ICV and transcranial distance. Currently, several non-invasive approaches to monitor ICP are being investigated. Such techniques include TMD and modal analysis of the skull. TMD may not be reliable over a large range of ICP and neither method is capable of measuring the small changes in pressure. Ultrasound, however, may reliably measure small distance changes that accompany ICP fluctuations. The purpose of our study was to develop and evaluate an ultrasound technique to measure transcranial distance changes during HDT.

  19. Guidelines for the diagnosis and management of disseminated intravascular coagulation

    NARCIS (Netherlands)

    Levi, M. [=Marcel M.; Toh, C. H.; Thachil, J.; Watson, H. G.

    2009-01-01

    The diagnosis of disseminated intravascular coagulation (DIC) should encompass both clinical and laboratory information. The International Society for Thrombosis and Haemostasis (ISTH) DIC scoring system provides objective measurement of DIC. Where DIC is present the scoring system correlates with

  20. Reliability of ultrasound for measurement of selected foot structures.

    Science.gov (United States)

    Crofts, G; Angin, S; Mickle, K J; Hill, S; Nester, C J

    2014-01-01

    Understanding the relationship between the lower leg muscles, foot structures and function is essential to explain how disease or injury may relate to changes in foot function and clinical pathology. The aim of this study was to investigate the inter-operator reliability of an ultrasound protocol to quantify features of: rear, mid and forefoot sections of the plantar fascia (PF); flexor hallucis brevis (FHB); flexor digitorum brevis (FDB); abductor hallucis (AbH); flexor digitorum longus (FDL); flexor hallucis longus (FHL); tibialis anterior (TA); and peroneus longus and brevis (PER). A sample of 6 females and 4 males (mean age 29.1 ± 7.2 years, mean BMI 25.5 ± 4.8) was recruited from a university student and staff population. Scans were obtained using a portable Venue 40 musculoskeletal ultrasound system (GE Healthcare UK) with a 5-13 MHz wideband linear array probe with a 12.7 mm × 47.1mm footprint by two operators in the same scanning session. Intraclass Correlation Coefficients (ICC) values for muscle thickness (ICC range 0.90-0.97), plantar fascia thickness (ICC range 0.94-0.98) and cross sectional muscle measurements (ICC range 0.91-0.98) revealed excellent inter-operator reliability. The limits of agreement, relative to structure size, ranged from 9.0% to 17.5% for muscle thickness, 11.0-18.0% for plantar fascia, and 11.0-26.0% for cross sectional area measurements. The ultrasound protocol implemented in this work has been shown to be reliable. It therefore offers the opportunity to quantify the structures concerned and better understand their contributions to foot function. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.

  1. Cardiac variation of inferior vena cava: new concept in the evaluation of intravascular blood volume.

    Science.gov (United States)

    Nakamura, Kensuke; Tomida, Makoto; Ando, Takehiro; Sen, Kon; Inokuchi, Ryota; Kobayashi, Etsuko; Nakajima, Susumu; Sakuma, Ichiro; Yahagi, Naoki

    2013-07-01

    Evaluation of the intravascular blood volume is an important assessment in emergency and critical care medicine. Measurement of the inferior vena cava (IVC) respiratory variation by ultrasound echography is useful, but it entails subjective problems. We have hypothesized that IVC cardiac variation is also correlated with intravascular blood volume and analyzed it automatically using computer software of two kinds, later comparing the results. Snakes, software to track boundaries by curve line continuity, and template matching software were incorporated into a computer with an ultrasound machine to track the short-axis view of IVC automatically and analyze it with approximation by ellipse. Eight healthy volunteers with temporary mild hypovolemia underwent echography before and after passive leg raising and while wearing medical anti-shock trousers. IVC cardiac variation was visually decreased by both leg raising and medical anti-shock trousers. The collapse index (maximum - minimum/maximum) of area during three cardiac beats was decreased showing a good relationship to fluid load simulations; 0.24 ± 0.03 at baseline versus 0.11 ± 0.01 with leg raising and 0.12 ± 0.01 with medical anti-shock trousers. In conclusion, IVC cardiac variation has the potential to provide an evaluation of water volume. It presents some advantages in mechanical analysis over respiratory variation. At the very least, we need to exercise some caution with cardiac variation when evaluating respiratory variation.

  2. Logistic discriminant analysis of breast cancer using ultrasound measurement

    International Nuclear Information System (INIS)

    Abdolmaleki, P.; Mokhtari Dizaji, M.; Vahead, M.R.; Gity, M.

    2004-01-01

    Background: Logistic discriminant method was applied to differentiate malignant from benign in a group of patients with proved breast lesions of the basis of ultrasonic parameters. Materials and methods: Our database include 273 patients' ultrasonographic pictures consisting of 14 quantitative variables. The measured variables were ultrasound propagation velocity, acoustic impedance and attenuation coefficient at 10 MHz in breast lesions at 20, 25, 30 and 35 d ig c temperature, physical density and age. This database was randomly divided into the estimation of 201 and validation of 72 samples. The estimation samples were used to build the logistic discriminant model, and validation samples were used to validate the performance. Finally important criteria such as sensitivity, specificity, accuracy and area under the receiver operating characteristic curve were evaluated. Results: Our results showed that the logistic discriminant method was able to classify correctly 67 out of 72 cases presented in the validation sample. The results indicate a remarkable diagnostic accuracy of 93%. Conclusion: A logistic discriminator approach is capable of predicting the probability of malignancy of breast cancer. Features from ultrasonic measurement on ultrasound imaging is used in this approach

  3. Automatic ultrasound technique to measure angle of progression during labor.

    Science.gov (United States)

    Conversano, F; Peccarisi, M; Pisani, P; Di Paola, M; De Marco, T; Franchini, R; Greco, A; D'Ambrogio, G; Casciaro, S

    2017-12-01

    To evaluate the accuracy and reliability of an automatic ultrasound technique for assessment of the angle of progression (AoP) during labor. Thirty-nine pregnant women in the second stage of labor, with fetus in cephalic presentation, underwent conventional labor management with additional translabial sonographic examination. AoP was measured in a total of 95 acquisition sessions, both automatically by an innovative algorithm and manually by an experienced sonographer, who was blinded to the algorithm outcome. The results obtained from the manual measurement were used as the reference against which the performance of the algorithm was assessed. In order to overcome the common difficulties encountered when visualizing by sonography the pubic symphysis, the AoP was measured by considering as the symphysis landmark its centroid rather than its distal point, thereby assuring high measurement reliability and reproducibility, while maintaining objectivity and accuracy in the evaluation of progression of labor. There was a strong and statistically significant correlation between AoP values measured by the algorithm and the reference values (r = 0.99, P < 0.001). The high accuracy provided by the automatic method was also highlighted by the corresponding high values of the coefficient of determination (r 2  = 0.98) and the low residual errors (root mean square error = 2°27' (2.1%)). The global agreement between the two methods, assessed through Bland-Altman analysis, resulted in a negligible mean difference of 1°1' (limits of agreement, 4°29'). The proposed automatic algorithm is a reliable technique for measurement of the AoP. Its (relative) operator-independence has the potential to reduce human errors and speed up ultrasound acquisition time, which should facilitate management of women during labor. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

  4. Sonographic measurement of thyroid gland volume: A comparison of 2D and 3D ultrasound

    Energy Technology Data Exchange (ETDEWEB)

    Ying, Michael [Department of Optometry and Radiography, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong (China)]. E-mail: ormying@polyu.edu.hk; Sin Manhong [Department of Optometry and Radiography, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong (China); Pang, Shuk-fan [Department of Optometry and Radiography, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong (China)

    2005-11-01

    Aims: This study was undertaken to investigate the inter-observer reproducibility of 2D and 3D ultrasound in the measurement of thyroid gland volume. The symmetry of thyroid lobes in healthy subjects was also investigated. Materials and methods: The volume of the left and right lobes of the thyroid gland was measured in 20 healthy subjects (10 men and 10 women) using 2D and 3D ultrasound. On 2D ultrasound, the thyroid lobe volume was calculated by ellipsoid equation (volume = {pi}/6 x craniocaudal x mediolateral x anteroposterior dimensions), whereas 3D ultrasound volumetric measurements were performed with a 3D add-on system. In each subject, the thyroid gland was scanned by two operators to investigate inter-observer variability. Results: There was a moderate agreement between 2D and 3D ultrasound in the measurement of thyroid volume (r = 0.77). 3D ultrasound (90%) had a higher inter-observer reproducibility than 2D ultrasound (85%) in the measurements. About 74% of healthy subjects had the right thyroid lobe larger than the left lobe. Conclusion: 3D ultrasound is useful in the measurement of thyroid volume with a higher reproducibility than 2D ultrasound. Asymmetry of thyroid lobes was noted in healthy subjects.

  5. Sonographic measurement of thyroid gland volume: A comparison of 2D and 3D ultrasound

    International Nuclear Information System (INIS)

    Ying, Michael; Sin Manhong; Pang, Shuk-fan

    2005-01-01

    Aims: This study was undertaken to investigate the inter-observer reproducibility of 2D and 3D ultrasound in the measurement of thyroid gland volume. The symmetry of thyroid lobes in healthy subjects was also investigated. Materials and methods: The volume of the left and right lobes of the thyroid gland was measured in 20 healthy subjects (10 men and 10 women) using 2D and 3D ultrasound. On 2D ultrasound, the thyroid lobe volume was calculated by ellipsoid equation (volume = π/6 x craniocaudal x mediolateral x anteroposterior dimensions), whereas 3D ultrasound volumetric measurements were performed with a 3D add-on system. In each subject, the thyroid gland was scanned by two operators to investigate inter-observer variability. Results: There was a moderate agreement between 2D and 3D ultrasound in the measurement of thyroid volume (r = 0.77). 3D ultrasound (90%) had a higher inter-observer reproducibility than 2D ultrasound (85%) in the measurements. About 74% of healthy subjects had the right thyroid lobe larger than the left lobe. Conclusion: 3D ultrasound is useful in the measurement of thyroid volume with a higher reproducibility than 2D ultrasound. Asymmetry of thyroid lobes was noted in healthy subjects

  6. 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...... 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...

  7. Non-Invasive Measurement of Pulsatile Intracranial Pressures Using Ultrasound

    Science.gov (United States)

    Ueno, Toshiaki; Ballard, Richard E.; Shuer, Lawrence M.; Cantrell, John H.; Cantrell, John H.; Hargens, Alan R.

    1997-01-01

    Early detection of elevated intracranial pressure (ICP) will aid clinical decision-making for head trauma, brain tumor and other cerebrovascular diseases. Conventional methods, however, require surgical procedures which take time and are accompanied by increased risk of infection. Accordingly we have developed and refined a new ultrasound device to measure skull movements which are known to occur in conjunction with altered ICP. The principle of this device is based upon pulse phase locked loop (PPLL), which enables us to detect changes in distance on the order of microns between an ultrasound transducer on one side of the skull and the opposite inner surface of the cranium. The present study was designed to verify this measurement technique in cadavera. Transcranial distance was increased in steps of 10 mmHg from zero to 50 mmHg by saline infusion into the lateral ventricle of two cadavera. In separate experiments, pulsations of ICP with the amplitudes of zero to 2 mmHg were generated by rhythmic injections of saline using a syringe. When the ICP was stepwise increased from zero to 50 mmHg, transcranial distance increased in proportion with the ICP increase (y=12 x - 76, r=0.938), where y is changes in transcranial distance in microns and x is ICP in mmHg. In the data recorded while ICP pulsations were generated, fast Fourier transform analysis demonstrated that cranial pulsations were clearly associated with ICP pulsations. The results indicate that changes in transcranial distance is linearly correlated with those in ICP, and also that the PPLL device has sufficient sensitivity to detect transcranial pulsations which occur in association with the cardiac cycle. By analyzing the magnitude of cranial pulsations, we may be able to estimate the pressure-volume index in the cranium. As a result, estimates of intracranial compliance may be possible by using the PPLL device. Further studies are necessary in normal subjects and patients.

  8. Quality management of nuchal translucency ultrasound measurement in Australia.

    Science.gov (United States)

    Nisbet, Debbie; Robertson, Ann; Mannil, Blessy; Pincham, Vanessa; Mclennan, Andrew

    2018-02-22

    Nuchal translucency measurement has an established role in first trimester screening. Accurate measurement requires that technical guidelines are followed. Performance can be monitored by auditing the distribution of measurements obtained in a series of cases. The primary aim is to develop an accessible, theory-based educational program for individuals whose distribution of measurements at audit falls outside an acceptable range, and assess operator performance following this intervention. Operators whose nuchal translucency measurement distributions fall outside a normal range (38-65% above the median) were expected to undergo a teleconference tutorial. Accessible from anywhere in Australia, the one hour tutorials were run by a senior sonographer (to explain technical ultrasound aspects) and the audit program manager (to explain the audit process). In 2011, 83 operators attended the teleconference tutorials. Compared to a random comparison group of operators meeting standard in 2011, teleconference tutorial attendees were significantly more likely to: (i) operate in rural or regional, rather than metropolitan, centres (P = 0.001); (ii) be less experienced (P audit cycle and was maintained over subsequent years. The mean percentage of the study cohort reaching standard over the five-year audit was 77.8% which was not statistically different from the average for the comparison cohort of all other audited operators (79.3%; P = 0.61). Teleconference tutorials are a convenient, accessible and effective way to obtain immediate and sustained improvement in operator performance. © 2018 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists.

  9. [Renal length measured by ultrasound in adult mexican population].

    Science.gov (United States)

    Oyuela-Carrasco, J; Rodríguez-Castellanos, F; Kimura, E; Delgado-Hernández, R; Herrera-Félix, J P

    2009-01-01

    Renal length estimation by ultrasound is an important parameter in clinical evaluation of kidney disease and healthy donors. Changes in renal volume may be a sign of kidney disease. Correct interpretation of renal length requires the knowledge of normal limits, these have not been described for Latin American population. To describe normal renal length (RL) by ultrasonography in a group of Mexican adults. Ultrasound measure of RL in 153 healthy Mexican adults stratified by age. Describe the association of RL to several anthropometric variables. A total of 77 males and 76 females were scanner. The average age for the group was 44.12 +/- 15.44 years. The mean weight, body mass index (BMI) and height were 68.87 +/- 11.69 Kg, 26.77 +/- 3.82 kg/m2 and 160 +/- 8.62 cm respectively. Dividing the population by gender, showed a height of 166 +/- 6.15 cm for males and 154.7 +/- 5.97 cm for females (p =0.000). Left renal length (LRL) in the whole group was 105.8 +/- 7.56 mm and right renal length (RRL) was 104.3 +/- 6.45 mm (p = 0.000.) The LRL for males was 107.16 +/- 6.97 mm and for females was 104.6 +/- 7.96 mm. The average RRL for males was 105.74 +/- 5.74 mm and for females 102.99 +/- 6.85 mm (p = 0.008.) We noted that RL decreased with age and the rate of decline accelerates alter 60 years of age. Both lengths correlated significantly and positively with weight, BMI and height. The RL was significantly larger in males than in females in both kidneys (p = 0.036) in this Mexican population. Renal length declines after 60 years of age and specially after 70 years.

  10. Diffuse optical tomography using semiautomated coregistered ultrasound measurements

    Science.gov (United States)

    Mostafa, Atahar; Vavadi, Hamed; Uddin, K. M. Shihab; Zhu, Quing

    2017-12-01

    Diffuse optical tomography (DOT) has demonstrated huge potential in breast cancer diagnosis and treatment monitoring. DOT image reconstruction guided by ultrasound (US) improves the diffused light localization and lesion reconstruction accuracy. However, DOT reconstruction depends on tumor geometry provided by coregistered US. Experienced operators can manually measure these lesion parameters; however, training and measurement time are needed. The wide clinical use of this technique depends on its robustness and faster imaging reconstruction capability. This article introduces a semiautomated procedure that automatically extracts lesion information from US images and incorporates it into the optical reconstruction. An adaptive threshold-based image segmentation is used to obtain tumor boundaries. For some US images, posterior shadow can extend to the chest wall and make the detection of deeper lesion boundary difficult. This problem can be solved using a Hough transform. The proposed procedure was validated from data of 20 patients. Optical reconstruction results using the proposed procedure were compared with those reconstructed using extracted tumor information from an experienced user. Mean optical absorption obtained from manual measurement was 0.21±0.06 cm-1 for malignant and 0.12±0.06 cm-1 for benign cases, whereas for the proposed method it was 0.24±0.08 cm-1 and 0.12±0.05 cm-1, respectively.

  11. Reliability of measuring abductor hallucis muscle parameters using two different diagnostic ultrasound machines

    Directory of Open Access Journals (Sweden)

    Cameron Alyse FM

    2009-11-01

    Full Text Available Abstract Background Diagnostic ultrasound provides a method of analysing soft tissue structures of the musculoskeletal system effectively and reliably. The aim of this study was to evaluate within and between session reliability of measuring muscle dorso-plantar thickness, medio-lateral length and cross-sectional area, of the abductor hallucis muscle using two different ultrasound machines, a higher end Philips HD11 Ultrasound machine and clinically orientated Chison 8300 Deluxe Digital Portable Ultrasound System. Methods The abductor hallucis muscle of both the left and right feet of thirty asymptomatic participants was imaged and then measured using both ultrasound machines. Interclass correlation coefficients (ICC with 95% confidence intervals (CI were used to calculate both within and between session intra-tester reliability. Standard error of the measurement (SEM calculations were undertaken to assess difference between the actual measured score across trials and the smallest real difference (SRD was calculated from the SEM to indicate the degree of change that would exceed the expected trial to trial variability. Results The ICCs, SEM and SRD for dorso-plantar thickness and medial-lateral length were shown to have excellent to high within and between-session reliability for both ultrasound machines. The between-session reliability indices for cross-sectional area were acceptable for both ultrasound machines. Conclusion The results of the current study suggest that regardless of the type ultrasound machine, intra-tester reliability for the measurement the abductor hallucis muscle parameters is very high.

  12. Carotid stenosis measurement on colour Doppler ultrasound: Agreement of ECST, NASCET and CCA methods applied to ultrasound with intra-arterial angiographic stenosis measurement

    International Nuclear Information System (INIS)

    Wardlaw, Joanna M.; Lewis, Steff

    2005-01-01

    Purpose: Carotid stenosis is usually determined on Doppler ultrasound from velocity readings. We wondered if angiography-style stenosis measurements applied to ultrasound images improved accuracy over velocity readings alone, and if so, which measure correlated best with angiography. Materials and methods: We studied prospectively patients undergoing colour Doppler ultrasound (CDU) for TIA or minor stroke. Those with 50%+ symptomatic internal carotid artery (ICA) stenosis had intra-arterial angiography (IAA). We measured peak systolic ICA velocity, and from the ultrasound image, the minimal residual lumen, the original lumen (ECST), ICA diameter distal (NASCET) and CCA diameter proximal (CCA method) to the stenosis. The IAAs were measured by ECST, NASCET and CCA methods also, blind to CDU. Results: Amongst 164 patients (328 arteries), on CDU the ECST, NASCET and CCA stenosis measures were similarly related to each other (ECST = 0.54 NASCET + 46) as on IAA (ECST = 0.6 NASCET + 40). Agreement between CDU- and IAA-measured stenosis was similar for ECST (r = 0.51), and CCA (r = 0.48) methods, and slightly worse for NASCET (r = 0.41). Adding IAA-style stenosis to the peak systolic ICA velocity did not improve agreement with IAA over peak systolic velocity alone. Conclusion: Angiography-style stenosis measures have similar inter-relationships when applied to CDU, but do not improve accuracy of ultrasound over peak systolic ICA velocity alone

  13. Dosimetry in intravascular brachytherapy

    International Nuclear Information System (INIS)

    Campos, Laelia Pumilla Botelho

    2000-03-01

    Among the cardiovascular diseases responsible for deaths in the adult population in almost all countries of the world, the most common is acute myocardial infarction, which generally occurs because of the occlusion of one or more coronary arteries. Several diagnostic techniques and therapies are being tested for the treatment of coronary artery disease. Balloon angioplasty has been a popular treatment which is less invasive than traditional surgeries involving revascularization of the myocardium, thus promising a better quality of life for patients. Unfortunately, the rate of restenosis (re-closing of the vessel) after balloon angioplasty is high (approximately 30-50% within the first year after treatment).Recently, the idea of delivering high radiation doses to coronary arteries to avoid or delay restenosis has been suggested. Known as intravascular brachytherapy, the technique has been used with several radiation sources, and researchers have obtained success in decreasing the rate of restenosis in some patient populations. In order to study the radiation dosimetry in the patient and radiological protection for the attending staff for this therapy, radiation dose distributions for monoenergetic electrons and photons (at nine discrete energies) were calculated for blood vessels of diameter 0.15, o,30 and 0.45 cm with balloon and wire sources using the radiation transport code MCNP4B. Specific calculations were carried out for several candidate radionuclides as well. Two s tent sources (metallic prosthesis that put inside of patient's artery through angioplasty) employing 32 P are also simulated. Advantages and disadvantages of the various radionuclides and source geometries are discussed. The dosimetry developed here will aid in the realization of the benefits obtained in patients for this promising new technology. (author)

  14. Achievement report for fiscal 1999 on research and development of technologies for medical welfare equipment. Intravascular 3D ultrasound imaging system for supporting less invasive diagnosis; 1999 nendo iryo fukushi kiki gijutsu kenkyu kaihatsu seika hokokusho. Shindan shiengata choonpa kekkannai sanjigen imaging system

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-05-01

    An ultrasonic probe with its point fine is navigated in blood vessels and body cavities by 3-dimensional ultrasonic signals (with the oscillator driven by transmission from a catheter for position detection) for the acquisition of accurate 3-dimensional ultrasound images in a less invasive way. The transmission and reception circuits are provided with circuits for ultrasound tomographic images and for navigation. Trial units are fabricated and tested for transmission waveform and reception performance. The scanner is rotated for the acquisition of intravascular 3-dimensional radial images. The scanner rotating rate is set at 30 rps for the scanner performance not to be affected by heartbeat and the rate is controlled by the observation unit which changes voltage for the control. The 3-dimensional display software program, thanks to the navigation function of the external probe, detects the external probe position relative to the small-diameter probe for the construction of accurate 3-dimensional images. Specifications for a total system, which makes full use of a navigation function, are compiled, consisting of a small-diameter probe and a body surface real-time 3-dimensional display. (NEDO)

  15. Design of a Thermoacoustic Sensor for Low Intensity Ultrasound Measurements Based on an Artificial Neural Network.

    Science.gov (United States)

    Xing, Jida; Chen, Jie

    2015-06-23

    In therapeutic ultrasound applications, accurate ultrasound output intensities are crucial because the physiological effects of therapeutic ultrasound are very sensitive to the intensity and duration of these applications. Although radiation force balance is a benchmark technique for measuring ultrasound intensity and power, it is costly, difficult to operate, and compromised by noise vibration. To overcome these limitations, the development of a low-cost, easy to operate, and vibration-resistant alternative device is necessary for rapid ultrasound intensity measurement. Therefore, we proposed and validated a novel two-layer thermoacoustic sensor using an artificial neural network technique to accurately measure low ultrasound intensities between 30 and 120 mW/cm2. The first layer of the sensor design is a cylindrical absorber made of plexiglass, followed by a second layer composed of polyurethane rubber with a high attenuation coefficient to absorb extra ultrasound energy. The sensor determined ultrasound intensities according to a temperature elevation induced by heat converted from incident acoustic energy. Compared with our previous one-layer sensor design, the new two-layer sensor enhanced the ultrasound absorption efficiency to provide more rapid and reliable measurements. Using a three-dimensional model in the K-wave toolbox, our simulation of the ultrasound propagation process demonstrated that the two-layer design is more efficient than the single layer design. We also integrated an artificial neural network algorithm to compensate for the large measurement offset. After obtaining multiple parameters of the sensor characteristics through calibration, the artificial neural network is built to correct temperature drifts and increase the reliability of our thermoacoustic measurements through iterative training about ten seconds. The performance of the artificial neural network method was validated through a series of experiments. Compared to our previous

  16. Accuracy of ultrasound-measured bladder wall thickness for the ...

    African Journals Online (AJOL)

    M.M. Ali

    history taking, general physical and genital examination, urine analysis, urine culture, blood chemistry, ... supine position, using an ultrasound device (BK Medical, Herlev, .... The standardisation of terminology of lower urinary tract function:.

  17. Central corneal thickness and anterior chamber depth measurement by Sirius® Scheimpflug tomography and ultrasound

    Directory of Open Access Journals (Sweden)

    Jorge J

    2013-02-01

    Full Text Available J Jorge,1 JL Rosado,2 JA Díaz-Rey,1 JM González-Méijome11Clinical and Experimental Optometry Research Laboratory, Center of Physics (Optometry, School of Sciences, University of Minho, Braga, 2Opticlinic, Lisboa, PortugalBackground: The purpose of this study was to compare the accuracy of the new Sirius® Scheimpflug anterior segment examination device for measurement of central corneal thickness (CCT and anterior chamber depth (ACD with that of CCT measurements obtained by ultrasound pachymetry and ACD measurements obtained by ultrasound biometry, respectively.Methods: CCT and ACD was measured in 50 right eyes from 50 healthy subjects using a Sirius Scheimpflug camera, SP100 ultrasound pachymetry, and US800 ultrasound biometry.Results: CCT measured with the Sirius was 546 ± 39 µm and 541 ± 35 µm with SP100 ultrasound pachymetry (P = 0.003. The difference was statistically significant (mean difference 4.68 ± 10.5 µm; limits of agreement −15.8 to 25.20 µm. ACD measured with the Sirius was 2.96 ± 0.3 mm compared with 3.36 ± 0.29 mm using US800 ultrasound biometry (P < 0.001. The difference was statistically significant (mean difference −0.40 ± 0.16 mm; limits of agreement −0.72 to 0.07 mm. When the ACD values obtained using ultrasound biometry were corrected according to the values for CCT measured by ultrasound, the agreement increased significantly between both technologies for ACD measurements (mean difference 0.15 ± 0.16 mm; limits of agreement −0.16 to 0.45 mm.Conclusion: CCT and ACD measured by Sirius and ultrasound methods showing good agreement between repeated measurements obtained in the same subjects (repeatability with either instrument. However, CCT and ACD values, even after correcting ultrasound ACD by subtracting the CCT value obtained with either technology should not be used interchangeably.Keywords: Scheimpflug corneal tomography, ultrasound biometry, ultrasound pachymetry, limits of agreement

  18. Intravascular bronchio-alveolar tumor

    International Nuclear Information System (INIS)

    Mata, J.M.; Caceres, J.; Prat, J.; Lopez, J.I.; Velilla, O.

    1991-01-01

    In 1975 Dail and Liebow described the clinical and pathological characteristics of a pulmonary tumor which they dominated intravascular bronchio-alveolar tumor (IVBAT). Our aim is to acquaint radiologists with the existence of this tumor by describing the radiologic findings in 2 patients with IVBAT, 1 with hepatic involvement ant the other with pulmonary osteoarthropathy. (author). 7 refs.; 2 figs

  19. General Ultrasound Imaging

    Medline Plus

    Full Text Available ... of an ultrasound examination. Doppler ultrasound , also called color Doppler ultrasonography, is a special ultrasound technique that ... kidneys. There are three types of Doppler ultrasound: Color Doppler uses a computer to convert Doppler measurements ...

  20. Factors Affecting Estimated Fetal Weight Measured by Ultrasound

    Directory of Open Access Journals (Sweden)

    Hasan Energin

    2016-06-01

    Full Text Available Objective: In this study, we aimed to evaluate the fac­tors that affect the accuracy of estimated fetal weight in ultrasound. Methods: This study was conducted in 3rd degree hospi­tal antenatal outpatient clinic and perinatology inpatient clinic between June 2011 and January 2012. The data were obtained from 165 pregnant women. Inclusion cri­teria were; no additional diseases, giving birth within 48 hours after ultrasound. The same physician executed all ultrasound process. Age, height, weight, obstetric history and obstetric follow –up findings were recorded. Results: Fetal gender, fetal presentation, presence of meconium in amniotic fluid, maternal parity, did not sig­nificantly affect the accuracy of fetal weight estimation by ultrasound. The mean difference between estimated fetal weight and birth weight was 104.48±84 gr in nullipars and 94.2±81 gr in multipars (p=0.44; mean difference was 98.22±79 gr in male babies and 98.15±86 gr in female babies (p=0.99. Mean difference between estimated fetal weight and birth weight was 96.92±81 gr in babies with cephalic presentation and 110.9±90 gr in babies with breech presentation (p=0.53; this difference was 95.36±79 gr in babies with amniotic fluid with meconium and 98.82± 83 gr in babies with amniotic fluid without me­conium (p=0.83. Conclusion: Fetal weight is estimation is one of key points in the obstetrician’s intrapartum managament. And it is important to make fetal weight estimation accurately. In our study, consistent with literature, we observed that fetal gender; meconium presence in amniotic fluid, fetal presentation, maternal parity does not significantly effect the accuracy of fetal weight estimation by ultrasound.

  1. Protection against high intravascular pressure in giraffe legs

    DEFF Research Database (Denmark)

    Petersen, Karin K; Hørlyck, Arne; Østergaard, Kristine Hovkjær

    2013-01-01

    The high blood pressure in giraffe leg arteries renders giraffes vulnerable to edema. We investigated in 11 giraffes whether large and small arteries in the legs and the tight fascia protect leg capillaries. Ultrasound imaging of foreleg arteries in anesthetized giraffes and ex vivo examination....... All three findings can contribute to protection of the capillaries in giraffe legs from a high arterial pressure....... revealed abrupt thickening of the arterial wall and a reduction of its internal diameter just below the elbow. At and distal to this narrowing, the artery constricted spontaneously and in response to norepinephrine and intravascular pressure recordings revealed a dynamic, viscous pressure drop along...

  2. Ultrasound -- Pelvis

    Medline Plus

    Full Text Available ... size, shape and consistency (whether the object is solid or filled with fluid). In medicine, ultrasound is ... ultrasound, measures the direction and speed of blood cells as they move through vessels. The movement of ...

  3. Ultrasound -- Pelvis

    Medline Plus

    Full Text Available ... needles are used to extract a sample of cells from organs for laboratory testing. Doppler ultrasound images ... ultrasound, measures the direction and speed of blood cells as they move through vessels. The movement of ...

  4. 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

    2014-11-01

    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. Copyright © 2014 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  5. Paediatric renal length measurements from ultrasound and DMSA scans: does clinical practice reflect theoretical normal values?

    International Nuclear Information System (INIS)

    Que, L.; Rutland, M.D.; Hassan, I.M.

    1999-01-01

    Full text: Renal length measurement is a routine part of ultrasound examination in children and those results are plotted on a normogram style graph, so that each child's results are compared to a normal range (mean ± 2 S.D.). Renal length measurements from the posterior oblique views of dimercaptosuccinic acid (DMSA) scans in our department have not always correlated well with the ultrasound measurements on the same patients. Renal lengths from the DMSA scans of 120 patients with apparently normal kidneys were recorded and used to generate a normogram of renal length at different ages (0.5-7 years). This DMSA normogram was compared to the ultrasound (US) normogram used in the Paediatric Radiology Department, and it showed slight differences in renal lengths (3-8 mm), but that the US normogram had smaller coefficients of variation (US = 6.6%, NM 8.3%), implying a 'tighter' normal range. 39 of these patients had DMSA and ultrasound measurements of renal length within 3 months, and these were studied first by calculating the mean and CV values for different age groups, and then by plotting individual renal lengths on the appropriate normograms. The measured data produced much greater variability in the ultrasound measurements than the DTPA measurements, and the individual points produced 4/78 (5.1%) abnormal results for DMSA, but 21/78 (26.9%) abnormal results for ultrasound. Thus, in routine clinical use, using patients with apparently normal kidneys, ultrasound was unable to match the 'normal range' set by their current normogram, but the nuclear medicine showed 5.1% of values outside the normal (DMSA) range, which was completely appropriate for a range of ± 2 standard deviations

  6. Superficial Ultrasound Shear Wave Speed Measurements in Soft and Hard Elasticity Phantoms: Repeatability and Reproducibility Using Two Different Ultrasound Systems

    Science.gov (United States)

    Dillman, Jonathan R.; Chen, Shigao; Davenport, Matthew S.; Zhao, Heng; Urban, Matthew W.; Song, Pengfei; Watcharotone, Kuanwong; Carson, Paul L.

    2014-01-01

    Background There is a paucity of data available regarding the repeatability and reproducibility of superficial shear wave speed (SWS) measurements at imaging depths relevant to the pediatric population. Purpose To assess the repeatability and reproducibility of superficial shear wave speed (SWS) measurements acquired from elasticity phantoms at varying imaging depths using three different imaging methods, two different ultrasound systems, and multiple operators. Methods and Materials Soft and hard elasticity phantoms manufactured by Computerized Imaging Reference Systems, Inc. (Norfolk, VA) were utilized for our investigation. Institution #1 used an Acuson S3000 ultrasound system (Siemens Medical Solutions USA, Inc.) and three different shear wave imaging method/transducer combinations, while institution #2 used an Aixplorer ultrasound system (Supersonic Imagine) and two different transducers. Ten stiffness measurements were acquired from each phantom at three depths (1.0, 2.5, and 4.0 cm) by four operators at each institution. Student’s t-test was used to compare SWS measurements between imaging techniques, while SWS measurement agreement was assessed with two-way random effects single measure intra-class correlation coefficients and coefficients of variation. Mixed model regression analysis determined the effect of predictor variables on SWS measurements. Results For the soft phantom, the average of mean SWS measurements across the various imaging methods and depths was 0.84 ± 0.04 m/s (mean ± standard deviation) for the Acuson S3000 system and 0.90 ± 0.02 m/s for the Aixplorer system (p=0.003). For the hard phantom, the average of mean SWS measurements across the various imaging methods and depths was 2.14 ± 0.08 m/s for the Acuson S3000 system and 2.07 ± 0.03 m/s Aixplorer system (p>0.05). The coefficients of variation were low (0.5–6.8%), and inter-operator agreement was near-perfect (ICCs ≥0.99). Shear wave imaging method and imaging depth

  7. Design of a Thermoacoustic Sensor for Low Intensity Ultrasound Measurements Based on an Artificial Neural Network

    Directory of Open Access Journals (Sweden)

    Jida Xing

    2015-06-01

    Full Text Available In therapeutic ultrasound applications, accurate ultrasound output intensities are crucial because the physiological effects of therapeutic ultrasound are very sensitive to the intensity and duration of these applications. Although radiation force balance is a benchmark technique for measuring ultrasound intensity and power, it is costly, difficult to operate, and compromised by noise vibration. To overcome these limitations, the development of a low-cost, easy to operate, and vibration-resistant alternative device is necessary for rapid ultrasound intensity measurement. Therefore, we proposed and validated a novel two-layer thermoacoustic sensor using an artificial neural network technique to accurately measure low ultrasound intensities between 30 and 120 mW/cm2. The first layer of the sensor design is a cylindrical absorber made of plexiglass, followed by a second layer composed of polyurethane rubber with a high attenuation coefficient to absorb extra ultrasound energy. The sensor determined ultrasound intensities according to a temperature elevation induced by heat converted from incident acoustic energy. Compared with our previous one-layer sensor design, the new two-layer sensor enhanced the ultrasound absorption efficiency to provide more rapid and reliable measurements. Using a three-dimensional model in the K-wave toolbox, our simulation of the ultrasound propagation process demonstrated that the two-layer design is more efficient than the single layer design. We also integrated an artificial neural network algorithm to compensate for the large measurement offset. After obtaining multiple parameters of the sensor characteristics through calibration, the artificial neural network is built to correct temperature drifts and increase the reliability of our thermoacoustic measurements through iterative training about ten seconds. The performance of the artificial neural network method was validated through a series of experiments. Compared

  8. Strain measurement of abdominal aortic aneurysm with real-time 3D ultrasound speckle tracking.

    Science.gov (United States)

    Bihari, P; Shelke, A; Nwe, T H; Mularczyk, M; Nelson, K; Schmandra, T; Knez, P; Schmitz-Rixen, T

    2013-04-01

    Abdominal aortic aneurysm rupture is caused by mechanical vascular tissue failure. Although mechanical properties within the aneurysm vary, currently available ultrasound methods assess only one cross-sectional segment of the aorta. This study aims to establish real-time 3-dimensional (3D) speckle tracking ultrasound to explore local displacement and strain parameters of the whole abdominal aortic aneurysm. Validation was performed on a silicone aneurysm model, perfused in a pulsatile artificial circulatory system. Wall motion of the silicone model was measured simultaneously with a commercial real-time 3D speckle tracking ultrasound system and either with laser-scan micrometry or with video photogrammetry. After validation, 3D ultrasound data were collected from abdominal aortic aneurysms of five patients and displacement and strain parameters were analysed. Displacement parameters measured in vitro by 3D ultrasound and laser scan micrometer or video analysis were significantly correlated at pulse pressures between 40 and 80 mmHg. Strong local differences in displacement and strain were identified within the aortic aneurysms of patients. Local wall strain of the whole abdominal aortic aneurysm can be analysed in vivo with real-time 3D ultrasound speckle tracking imaging, offering the prospect of individual non-invasive rupture risk analysis of abdominal aortic aneurysms. Copyright © 2013 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

  9. Ultrasound pregnancy

    Science.gov (United States)

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

  10. Intravascular photoacoustic imaging: a new tool for vulnerable plaque identification.

    Science.gov (United States)

    Jansen, Krista; van Soest, Gijs; van der Steen, Antonius F W

    2014-06-01

    The vulnerable atherosclerotic plaque is believed to be at the root of the majority of acute coronary events. Even though the exact origins of plaque vulnerability remain elusive, the thin-cap fibroatheroma, characterized by a lipid-rich necrotic core covered by a thin fibrous cap, is considered to be the most prominent type of vulnerable plaque. No clinically available imaging technique can characterize atherosclerotic lesions to the extent needed to determine plaque vulnerability prognostically. Intravascular photoacoustic imaging (IVPA) has the potential to take a significant step in that direction by imaging both plaque structure and composition. IVPA is a natural extension of intravascular ultrasound that adds tissue type specificity to the images. IVPA utilizes the optical contrast provided by the differences in the absorption spectra of plaque components to image composition. Its capability to image lipids in human coronary atherosclerosis has been shown extensively ex vivo and has recently been translated to an in vivo animal model. Other disease markers that have been successfully targeted are calcium and inflammatory markers, such as macrophages and matrix metalloproteinase; the latter two through application of exogenous contrast agents. By simultaneously displaying plaque morphology and composition, IVPA can provide a powerful prognostic marker for disease progression, and as such has the potential to transform the current practice in percutaneous coronary intervention. Copyright © 2014 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  11. Feasibility of Quantitative Ultrasound Measurement of the Heel Bone in People with Intellectual Disabilities

    Science.gov (United States)

    Mergler, S.; Lobker, B.; Evenhuis, H. M.; Penning, C.

    2010-01-01

    Low bone mineral density (BMD) and fractures are common in people with intellectual disabilities (ID). Reduced mobility in case of motor impairment and the use of anti-epileptic drugs contribute to the development of low BMD. Quantitative ultrasound (QUS) measurement of the heel bone is a non-invasive and radiation-free method for measuring bone…

  12. Blood flow measurements during hemodialysis vascular access interventions - Catheter-based thermodilution or Doppler ultrasound?

    DEFF Research Database (Denmark)

    Heerwagen, Søren T; Hansen, Marc A; Schroeder, Torben V

    2012-01-01

    by ultrasound dilution was determined within three days of the procedure. The methods were compared using regression analysis and tested for systematic bias. Results: Failure to position the thermodilutional catheter correctly was observed in 8 out of 46 (17%) pre-intervention measurements. Post-intervention......Purpose: To test the clinical performance of catheter-based thermodilution and Doppler ultrasound of the feeding brachial artery for blood flow measurements during hemodialysis vascular access interventions.Methods: Thirty patients with arteriovenous fistulas who underwent 46 interventions had...

  13. Challenges and regulatory considerations in the acoustic measurement of high-frequency (>20 MHz) ultrasound.

    Science.gov (United States)

    Nagle, Samuel M; Sundar, Guru; Schafer, Mark E; Harris, Gerald R; Vaezy, Shahram; Gessert, James M; Howard, Samuel M; Moore, Mary K; Eaton, Richard M

    2013-11-01

    This article examines the challenges associated with making acoustic output measurements at high ultrasound frequencies (>20 MHz) in the context of regulatory considerations contained in the US Food and Drug Administration industry guidance document for diagnostic ultrasound devices. Error sources in the acoustic measurement, including hydrophone calibration and spatial averaging, nonlinear distortion, and mechanical alignment, are evaluated, and the limitations of currently available acoustic measurement instruments are discussed. An uncertainty analysis of acoustic intensity and power measurements is presented, and an example uncertainty calculation is done on a hypothetical 30-MHz high-frequency ultrasound system. This analysis concludes that the estimated measurement uncertainty of the acoustic intensity is +73%/-86%, and the uncertainty in the mechanical index is +37%/-43%. These values exceed the respective levels in the Food and Drug Administration guidance document of 30% and 15%, respectively, which are more representative of the measurement uncertainty associated with characterizing lower-frequency ultrasound systems. Recommendations made for minimizing the measurement uncertainty include implementing a mechanical positioning system that has sufficient repeatability and precision, reconstructing the time-pressure waveform via deconvolution using the hydrophone frequency response, and correcting for hydrophone spatial averaging.

  14. The use of three-dimensional ultrasound does not improve training in fetal biometric measurements.

    Science.gov (United States)

    Chan, Lin W; Ting, Yuen H; Lao, Terence T; Chau, Macy M C; Fung, Tak Y; Leung, Tak Y; Sahota, Daljit S; Lau, Tze K

    2011-09-01

    To investigate whether three-dimensional (3D) technology offers any advantage over two-dimensional (2D) ultrasound in fetal biometric measurement training. Ten midwives with no hands-on experience in ultrasound were randomized to receive training on 2D or 3D ultrasound fetal biometry assessment. Midwives were taught how to obtain fetal biometric measurements (biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC), and femur length (FL)) by a trainer. Subsequently, each midwife measured the parameters on another 10 fetuses. The same set of measurements was repeated by the trainer. The percentage deviation between the midwives' and the trainer's measurements was determined and compared between training groups. Time required for completion was recorded. Frozen images were reviewed by another sonographer to assess the image quality using a standardized scoring system. The median time for the complete set of measurements was significantly shorter in the 2D than in 3D group (13.4 min versus 17.8 min, P = 0.03). The mean percentage deviations did not reach statistical significance between the two groups except for FL (3.83% in 2D group versus 2.23% in 3D group (P = 0.046)). There were no significant differences in the quality scores. This study showed that the only demonstrable advantage of 3D ultrasound was a slightly more accurate measurement of FL, at the expense of a significantly longer time required.

  15. 21 CFR 880.5200 - Intravascular catheter.

    Science.gov (United States)

    2010-04-01

    ... Devices § 880.5200 Intravascular catheter. (a) Identification. An intravascular catheter is a device that consists of a slender tube and any necessary connecting fittings and that is inserted into the patient's vascular system for short term use (less than 30 days) to sample blood, monitor blood pressure, or...

  16. The effects of serial intravascular transfusions in ascitic/hydropic RhD-alloimmunized fetuses.

    Science.gov (United States)

    Craparo, F J; Bonati, F; Gementi, P; Nicolini, U

    2005-02-01

    To evaluate the effects of serial intravascular transfusions on RhD-alloimmunized fetuses with ascites/hydrops at the time of the first transfusion by measuring multiple hematological/biochemical blood variables. Thirty-one singleton pregnancies were referred for management of RhD alloimmunization. Seven fetuses had hydrops on presentation and were transfused immediately. The remainder underwent weekly ultrasound examinations, and fetal blood sampling and transfusion were performed on development of ascites. In the 104 samples collected overall from the 31 fetuses, glucose, uric acid, urea, creatinine, total protein, total and direct bilirubin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyltransferase, alkaline phosphatase, lactic dehydrogenase, amylase, pseudocholinesterase (PCHE), creatine kinase, triglycerides and cholesterol were measured and compared with a reference range for non-anemic fetuses. The median gestational age at first transfusion was 26 (range, 18-34) weeks. There were three fetal losses after the first transfusion, two of which were due to procedure-related complications; one further loss occurred. At the first transfusion fetal hematocrit, pO2, total protein, PCHE, creatinine and urea concentrations were significantly decreased compared to reference data, while total and direct bilirubin, AST, ALT, amylase, triglyceride and uric acid concentrations were increased. In all surviving fetuses ascites/hydrops had disappeared by the second transfusion. Fetal pO2, total protein, AST, ALT and PCHE concentrations had normalized by the third transfusion. Correction of fetal anemia did not affect the other variables. RhD-alloimmunized fetuses with ascites/hydrops at the time of the first transfusion had a survival rate of 87%. Alterations of several biochemical fetal blood indices are present at the first sampling/transfusion, but most variables normalize with intravascular transfusions. Copyright 2005 ISUOG.

  17. A study of pipe flow rate measurement using air-coupled ultrasound

    International Nuclear Information System (INIS)

    Tsukada, Keisuke; Tsuzuki, Nobuyoshi; Kikura, Hiroshige

    2013-01-01

    A non-contact flow meter employing air-coupled ultrasound is developed in this research. Ultrasonic flow meter is applied to the higher accuracy flow rate measurement, compared with pressure difference flow meter. However, ultrasonic flow meter has difficulty to measure in severe conditions such as in the condition of high temperature, high pressure condition, and radioactive materials in fluid. Especially, in high temperature condition, piezoelectric device in ultrasonic sensors lose the piezoelectricity, and it becomes difficult to transmit or detect ultrasound. Thus, in this research, ultrasonic sensors are fixed in the air. Ultrasonic sensors transmit and detect ultrasound through air, and measure the flow rate in the pipe. However, most of ultrasound is refracted and reflected at the boundaries between air and the pipe. And detected signals are weak. To increase the signal level, we developed focusing ultrasonic sensors that was optimized for the pipe flow measurement. And employing these focusing sensors the flow rate measurement has been done in order to evaluate the air-coupled ultrasonic flow meter by the ultrasonic beam focusing technique. (author)

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

    Science.gov (United States)

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

    2009-05-01

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

  19. Quantitative Ultrasound for Measuring Obstructive Severity in Children with Hydronephrosis.

    Science.gov (United States)

    Cerrolaza, Juan J; Peters, Craig A; Martin, Aaron D; Myers, Emmarie; Safdar, Nabile; Linguraru, Marius George

    2016-04-01

    We define sonographic biomarkers for hydronephrotic renal units that can predict the necessity of diuretic nuclear renography. We selected a cohort of 50 consecutive patients with hydronephrosis of varying severity in whom 2-dimensional sonography and diuretic mercaptoacetyltriglycine renography had been performed. A total of 131 morphological parameters were computed using quantitative image analysis algorithms. Machine learning techniques were then applied to identify ultrasound based safety thresholds that agreed with the t½ for washout. A best fit model was then derived for each threshold level of t½ that would be clinically relevant at 20, 30 and 40 minutes. Receiver operating characteristic curve analysis was performed. Sensitivity, specificity and area under the receiver operating characteristic curve were determined. Improvement obtained by the quantitative imaging method compared to the Society for Fetal Urology grading system and the hydronephrosis index was statistically verified. For the 3 thresholds considered and at 100% sensitivity the specificities of the quantitative imaging method were 94%, 70% and 74%, respectively. Corresponding area under the receiver operating characteristic curve values were 0.98, 0.94 and 0.94, respectively. Improvement obtained by the quantitative imaging method over the Society for Fetal Urology grade and hydronephrosis index was statistically significant (p hydronephrosis can identify thresholds of clinically significant washout times with 100% sensitivity to decrease the number of diuretic renograms in up to 62% of children. Copyright © 2016 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  20. Interleaved quantitative BOLD: Combining extravascular R2' - and intravascular R2-measurements for estimation of deoxygenated blood volume and hemoglobin oxygen saturation.

    Science.gov (United States)

    Lee, Hyunyeol; Englund, Erin K; Wehrli, Felix W

    2018-03-23

    Quantitative BOLD (qBOLD), a non-invasive MRI method for assessment of hemodynamic and metabolic properties of the brain in the baseline state, provides spatial maps of deoxygenated blood volume fraction (DBV) and hemoglobin oxygen saturation (HbO 2 ) by means of an analytical model for the temporal evolution of free-induction-decay signals in the extravascular compartment. However, mutual coupling between DBV and HbO 2 in the signal model results in considerable estimation uncertainty precluding achievement of a unique set of solutions. To address this problem, we developed an interleaved qBOLD method (iqBOLD) that combines extravascular R 2 ' and intravascular R 2 mapping techniques so as to obtain prior knowledge for the two unknown parameters. To achieve these goals, asymmetric spin echo and velocity-selective spin-labeling (VSSL) modules were interleaved in a single pulse sequence. Prior to VSSL, arterial blood and CSF signals were suppressed to produce reliable estimates for cerebral venous blood volume fraction (CBV v ) as well as venous blood R 2 (to yield HbO 2 ). Parameter maps derived from the VSSL module were employed to initialize DBV and HbO 2 in the qBOLD processing. Numerical simulations and in vivo experiments at 3 T were performed to evaluate the performance of iqBOLD in comparison to the parent qBOLD method. Data obtained in eight healthy subjects yielded plausible values averaging 60.1 ± 3.3% for HbO 2 and 3.1 ± 0.5 and 2.0 ± 0.4% for DBV in gray and white matter, respectively. Furthermore, the results show that prior estimates of CBV v and HbO 2 from the VSSL component enhance the solution stability in the qBOLD processing, and thus suggest the feasibility of iqBOLD as a promising alternative to the conventional technique for quantifying neurometabolic parameters. Copyright © 2018. Published by Elsevier Inc.

  1. The cardiac cycle is a major contributor to variability in size measurements of abdominal aortic aneurysms by ultrasound

    DEFF Research Database (Denmark)

    Grøndal, Nikolaj Fibiger; Bramsen, Morten; Thomsen, Marie Dahl

    2012-01-01

    The objective of the study was to evaluate the impact of the cardiac cycle on ultrasound measurements of abdominal aortic aneurysm (AAA) diameters.......The objective of the study was to evaluate the impact of the cardiac cycle on ultrasound measurements of abdominal aortic aneurysm (AAA) diameters....

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

    International Nuclear Information System (INIS)

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

    2008-01-01

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

  3. STEREOCHEMICAL ASPECTS OF HYDRATION OF CARBOHYDRATES IN AQUEOUS-SOLUTIONS .3. DENSITY AND ULTRASOUND MEASUREMENTS

    NARCIS (Netherlands)

    GALEMA, SA; HOILAND, H

    1991-01-01

    Density and ultrasound measurements have been performed in aqueous solutions of pentoses, hexoses, methylpyranosides, and disaccharides as a function of molality of carbohydrate (0-0.3 mol kg-1). Partial molar volumes, partial molar isentropic compressibilities, and hydration numbers have been

  4. Ultrasound measurements for the prediction of osteoporotic fractures in elderly people

    NARCIS (Netherlands)

    Pluijm, S.M.F.; Graafmans, W.C.; Bouter, L.M.; Lips, P.T.A.M.

    1999-01-01

    In this prospective study we investigated the predictive value of quantitative ultrasound (QUS) measurements and other potential predictors of osteoporotic fractures in the elderly. During a I-year period, 710 participants (132 men and 578 women), aged 70 years and older (mean age ± SD: 82.8 ± 5.9),

  5. An ultrasound mini-balance for measurement of therapy level ultrasound

    International Nuclear Information System (INIS)

    Sutton, Yvonne; McBride, Karne; Pye, Stephen

    2006-01-01

    This paper describes a cost-effective method for measuring acoustic power using a radiation force balance. The device is based around a long established balance design with a gantry arrangement fitted with an absorbing target. The notion of this balance design is that it can easily be constructed from materials that would be readily available within a clinical or industrial environment. The mini-balance was calibrated using a transfer standard against an NPL Reference balance, so a comparison of the performance between the two systems could be assessed. The measurements were completed at 1 MHz and 3 MHz and over the acoustic power range of 1 W to 15 W. The results show the acoustic power measured on the mini-balance to be within 5% of the reference measurements made on the NPL Balance. A separate systematic uncertainty budget is also presented based on studies made on the balance and on similar systems. The overall expanded uncertainty was calculated to be within 14% at 1 W level, decreasing with increasing power level to 7.4% above 5 W

  6. A comparison of portable ultrasound and fully-equipped clinical ultrasound unit in the thyroid size measurement of the Indo-Pacific bottlenose dolphin.

    Directory of Open Access Journals (Sweden)

    Brian C W Kot

    Full Text Available Measurement of thyroid size and volume is a useful clinical parameter in both human and veterinary medicine, particularly for diagnosing thyroid diseases and guiding corrective therapy. Procuring a fully-equipped clinical ultrasound unit (FCUS may be difficult in most veterinary settings. The present study evaluated the inter-equipment variability in dolphin thyroid ultrasound measurements between a portable ultrasound unit (PUS and a FCUS; for both units, repeatability was also assessed. Thyroid ultrasound examinations were performed on 15 apparently healthy bottlenose dolphins with both PUS and FCUS under identical scanning conditions. There was a high level of agreement between the two ultrasound units in dolphin thyroid measurements (ICC = 0.859-0.976. A high intra-operator repeatability in thyroid measurements was found (PUS: ICC = 0.854-0.984, FCUS: ICC = 0.709-0.954. As a conclusion, no substantial inter-equipment variability was found between PUS and FCUS in dolphin thyroid size measurements under identical scanning conditions, supporting further application of PUS for quantitative analyses of dolphin thyroid gland in both research and clinical practices at aquarium settings.

  7. Dynamic measurement of pennation angle of gastrocnemius muscles during contractions based on ultrasound imaging

    Directory of Open Access Journals (Sweden)

    Zhou Yongjin

    2012-09-01

    Full Text Available Abstract Background Muscle fascicle pennation angle (PA is an important parameter related to musculoskeletal functions, and ultrasound imaging has been widely used for measuring PA, but manually and frame by frame in most cases. We have earlier reported an automatic method to estimate aponeurosis orientation based on Gabor transform and Revoting Hough Transform (RVHT. Methods In this paper, we proposed a method to estimate the overall orientation of muscle fascicles in a region of interest, in order to complete computing the orientation of the other side of the pennation angle, but the side found by RVHT. The measurements for orientations of both fascicles and aponeurosis were conducted in each frame of ultrasound images, and then the dynamic change of pennation angle during muscle contraction was obtained automatically. The method for fascicle orientation estimation was evaluated using synthetic images with different noise levels and later on 500 ultrasound images of human gastrocnemius muscles during isometric plantarflexion. Results The muscle fascicle orientations were also estimated manually by two operators. From the results it’s found that the proposed automatic method demonstrated a comparable performance to the manual method. Conclusions With the proposed methods, ultrasound measurement for muscle pennation angles can be more widely used for functional assessment of muscles.

  8. Poststenotic flow disturbance in the dog aorta as measured with pulsed Doppler ultrasound.

    Science.gov (United States)

    Talukder, N; Fulenwider, J T; Mabon, R F; Giddens, D P

    1986-08-01

    Blood flow velocity was measured in the dog aorta distal to mechanically induced constrictions of various degrees of severity employing an 8-MHz pulsed Doppler ultrasound velocimeter and a phase-lock loop frequency tracking method for extracting velocity from the Doppler quadrature signals. The data were analyzed to construct ensemble average velocity waveforms and random velocity disturbances. In any individual animal the effect of increasing the degree of stenosis beyond approximately 25 percent area reduction was to produce increasing levels of random velocity disturbance. However, variability among animals was such that the sensitivity of random behavior to the degree of stenosis was degraded to the point that it appears difficult to employ Doppler ultrasound measurements of random disturbances to discriminate among stenoses with area reductions less than approximately 75 percent. On the other hand, coherent vortex structures in velocity waveforms consistently occurred distal to mild constrictions (25-50 percent area reduction). Comparison of the phase-lock loop Doppler ultrasound data with simultaneous measurements using invasive hot-film anemometry, which possesses excellent frequency response, demonstrates that the ultrasound method can reliably detect those flow phenomena in such cases. Thus, the identification of coherent, rather than random, flow disturbances may offer improved diagnostic capability for noninvasively detecting arteriosclerotic plaques at relatively early stages of development.

  9. Measuring the diameter of rising gas bubbles by means of the ultrasound transit time technique

    Energy Technology Data Exchange (ETDEWEB)

    Richter, T., E-mail: Thomas.Richter6@tu-dresden.de; Eckert, K., E-mail: Kerstin.Eckert@tu-dresden.de; Yang, X.; Odenbach, S.

    2015-09-15

    Highlights: • Ultrasound transit time technique (UTTT) is applied to the zig-zag raise of gas bubble. • Comparison of bubble diameter and tilt, measured by UTTT, with high-speed imaging. • Uncertainty in the determination of the bubble diameter by UTTT is less than 7%. • UTTT is able to measure dynamic changes in bubble size in opaque liquids and vessels. • UTTT can be applied to liquid metal loops. - Abstract: This study presents ultrasound transit time technique (UTTT) measurements of the diameter variations of single argon bubbles rising in a zig-zag trajectory in water. Simultaneous size measurements with a high-speed camera show that UTTT resolves both the apparent diameter and the tilt of the bubble axis with an accuracy of better than 7%. This qualifies UTTT for the measurement of bubble sizes in opaque liquids, such as liquid metals, or vessels.

  10. Development of a Duplex Ultrasound Simulator and Preliminary Validation of Velocity Measurements in Carotid Artery Models.

    Science.gov (United States)

    Zierler, R Eugene; Leotta, Daniel F; Sansom, Kurt; Aliseda, Alberto; Anderson, Mark D; Sheehan, Florence H

    2016-07-01

    Duplex ultrasound scanning with B-mode imaging and both color Doppler and Doppler spectral waveforms is relied upon for diagnosis of vascular pathology and selection of patients for further evaluation and treatment. In most duplex ultrasound applications, classification of disease severity is based primarily on alterations in blood flow velocities, particularly the peak systolic velocity (PSV) obtained from Doppler spectral waveforms. We developed a duplex ultrasound simulator for training and assessment of scanning skills. Duplex ultrasound cases were prepared from 2-dimensional (2D) images of normal and stenotic carotid arteries by reconstructing the common carotid, internal carotid, and external carotid arteries in 3 dimensions and computationally simulating blood flow velocity fields within the lumen. The simulator displays a 2D B-mode image corresponding to transducer position on a mannequin, overlaid by color coding of velocity data. A spectral waveform is generated according to examiner-defined settings (depth and size of the Doppler sample volume, beam steering, Doppler beam angle, and pulse repetition frequency or scale). The accuracy of the simulator was assessed by comparing the PSV measured from the spectral waveforms with the true PSV which was derived from the computational flow model based on the size and location of the sample volume within the artery. Three expert examiners made a total of 36 carotid artery PSV measurements based on the simulated cases. The PSV measured by the examiners deviated from true PSV by 8% ± 5% (N = 36). The deviation in PSV did not differ significantly between artery segments, normal and stenotic arteries, or examiners. To our knowledge, this is the first simulation of duplex ultrasound that can create and display real-time color Doppler images and Doppler spectral waveforms. The results demonstrate that an examiner can measure PSV from the spectral waveforms using the settings on the simulator with a mean absolute error

  11. 21 CFR 870.3375 - Cardiovascular intravascular filter.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiovascular intravascular filter. 870.3375... Cardiovascular intravascular filter. (a) Identification. A cardiovascular intravascular filter is an implant that... and Revision of 2/12/90 (K90-1)” and (ii) “Guidance for Cardiovascular Intravascular Filter 510(k...

  12. Effect of Heat Generation of Ultrasound Transducer on Ultrasonic Power Measured by Calorimetric Method

    Science.gov (United States)

    Uchida, Takeyoshi; Kikuchi, Tsuneo

    2013-07-01

    Ultrasonic power is one of the key quantities closely related to the safety of medical ultrasonic equipment. An ultrasonic power standard is required for establishment of safety. Generally, an ultrasonic power standard below approximately 20 W is established by the radiation force balance (RFB) method as the most accurate measurement method. However, RFB is not suitable for high ultrasonic power because of thermal damage to the absorbing target. Consequently, an alternative method to RFB is required. We have been developing a measurement technique for high ultrasonic power by the calorimetric method. In this study, we examined the effect of heat generation of an ultrasound transducer on ultrasonic power measured by the calorimetric method. As a result, an excessively high ultrasonic power was measured owing to the effect of heat generation from internal loss in the transducer. A reference ultrasound transducer with low heat generation is required for a high ultrasonic power standard established by the calorimetric method.

  13. Accurate evaluation of viscoelasticity of radial artery wall during flow-mediated dilation in ultrasound measurement

    Science.gov (United States)

    Sakai, Yasumasa; Taki, Hirofumi; Kanai, Hiroshi

    2016-07-01

    In our previous study, the viscoelasticity of the radial artery wall was estimated to diagnose endothelial dysfunction using a high-frequency (22 MHz) ultrasound device. In the present study, we employed a commercial ultrasound device (7.5 MHz) and estimated the viscoelasticity using arterial pressure and diameter, both of which were measured at the same position. In a phantom experiment, the proposed method successfully estimated the elasticity and viscosity of the phantom with errors of 1.8 and 30.3%, respectively. In an in vivo measurement, the transient change in the viscoelasticity was measured for three healthy subjects during flow-mediated dilation (FMD). The proposed method revealed the softening of the arterial wall originating from the FMD reaction within 100 s after avascularization. These results indicate the high performance of the proposed method in evaluating vascular endothelial function just after avascularization, where the function is difficult to be estimated by a conventional FMD measurement.

  14. Agreement between anatomic and ultrasound measurements of femoral trochlear depth

    DEFF Research Database (Denmark)

    Miles, James Edward; Westrup, Ulrik; Eriksen, Thomas

    and ultrasonographic measurements of trochlear depth using the red fox hind limb as a canine surrogate, dividing the trochlea into five regions from the origin of the caudal cruciate ligament to the proximal aspect of the trochlea. We found reasonable agreement between anatomic and ultrasonographic measurements...

  15. Validation of an ultrasound dilution technology for cardiac output measurement and shunt detection in infants and children.

    Science.gov (United States)

    Lindberg, Lars; Johansson, Sune; Perez-de-Sa, Valeria

    2014-02-01

    To validate cardiac output measurements by ultrasound dilution technology (COstatus monitor) against those obtained by a transit-time ultrasound technology with a perivascular flow probe and to investigate ultrasound dilution ability to estimate pulmonary to systemic blood flow ratio in children. Prospective observational clinical trial. Pediatric cardiac operating theater in a university hospital. In 21 children (6.1 ± 2.6 kg, mean ± SD) undergoing heart surgery, cardiac output was simultaneously recorded by ultrasound dilution (extracorporeal arteriovenous loop connected to existing arterial and central venous catheters) and a transit-time ultrasound probe applied to the ascending aorta, and when possible, the main pulmonary artery. The pulmonary to systemic blood flow ratio estimated from ultrasound dilution curve analysis was compared with that estimated from transit-time ultrasound technology. Bland-Altman analysis of the whole cohort (90 pairs, before and after surgery) showed a bias between transit-time ultrasound (1.01 ± 0.47 L/min) and ultrasound dilution technology (1.03 ± 0.51 L/min) of -0.02 L/min, limits of agreement -0.3 to 0.3 L/min, and percentage error of 31%. In children with no residual shunts, the bias was -0.04 L/min, limits of agreement -0.28 to 0.2 L/min, and percentage error 19%. The pooled co efficient of variation was for the whole cohort 3.5% (transit-time ultrasound) and 6.3% (ultrasound dilution), and in children without shunt, it was 2.9% (transit-time ultrasound) and 4% (ultrasound dilution), respectively. Ultrasound dilution identified the presence of shunts (pulmonary to systemic blood flow ≠ 1) with a sensitivity of 100% and a specificity of 92%. Mean pulmonary to systemic blood flow ratio by transit-time ultrasound was 2.6 ± 1.0 and by ultrasound dilution 2.2 ± 0.7 (not significant). The COstatus monitor is a reliable technique to measure cardiac output in children with high sensitivity and specificity for detecting the

  16. High speed intravascular photoacoustic imaging of atherosclerotic arteries (Conference Presentation)

    Science.gov (United States)

    Piao, Zhonglie; Ma, Teng; Qu, Yueqiao; Li, Jiawen; Yu, Mingyue; He, Youmin; Shung, K. Kirk; Zhou, Qifa; Kim, Chang-Seok; Chen, Zhongping

    2016-02-01

    Cardiovascular disease is the leading cause of death in the industrialized nations. Accurate quantification of both the morphology and composition of lipid-rich vulnerable atherosclerotic plaque are essential for early detection and optimal treatment in clinics. In previous works, intravascular photoacoustic (IVPA) imaging for detection of lipid-rich plaque within coronary artery walls has been demonstrated in ex vivo, but the imaging speed is still limited. In order to increase the imaging speed, a high repetition rate laser is needed. In this work, we present a high speed integrated IVPA/US imaging system with a 500 Hz optical parametric oscillator laser at 1725 nm. A miniature catheter with 1.0 mm outer diameter was designed with a 200 μm multimode fiber and an ultrasound transducer with 45 MHz center frequency. The fiber was polished at 38 degree and enclosed in a glass capillary for total internal reflection. An optical/electrical rotary junction and pull-back mechanism was applied for rotating and linearly scanning the catheter to obtain three-dimensional imaging. Atherosclerotic rabbit abdominal aorta was imaged as two frame/second at 1725 nm. Furthermore, by wide tuning range of the laser wavelength from 1680 nm to 1770 nm, spectroscopic photoacoustic analysis of lipid-mimicking phantom and an human atherosclerotic artery was performed ex vivo. The results demonstrated that the developed IVPA/US imaging system is capable for high speed intravascular imaging for plaque detection.

  17. AMH MEASUREMENT VERSUS OVARIAN ULTRASOUND IN THE DIAGNOSIS OF POLYCYSTIC OVARY SYNDROME IN DIFFERENT PHENOTYPES.

    Science.gov (United States)

    Carmina, Enrico; Campagna, Anna M; Fruzzetti, Franca; Lobo, Rogerio A

    2016-03-01

    This study was designed to assess the value of serum anti-Müllerian hormone (AMH) in the diagnosis of polycystic ovary syndrome (PCOS) in various phenotypes and to assess ovarian ultrasound parameters. We performed a retrospective matched controlled study of 113 females with various PCOS phenotypes and 47 matched controls. The diagnostic utility of AMH measurement and ovarian ultrasound were compared. Using receiver operating characteristic (ROC) curve analyses, the threshold for AMH (>4.7 ng/mL) and ultrasound parameters (follicle number per ovary [FNPO] >22 and ovarian volume [OV] >8 cc) were established. In the entire cohort, AMH had a low sensitivity of 79%; while FNPO and OV were 93% and 68%, respectively. Specificities ranged from 85 to 96%. In classic anovulatory PCOS, AMH exhibited a sensitivity of 91%, and for FNPO and OV the corresponding sensitivities were 92% and 72%. In the ovulatory phenotype, AMH sensitivity was only 50%, while FNPO and OV were 95% and 50%, respectively. In the nonhyperandrogenic phenotype, the sensitivity of AMH was 53% while those for FNPO and OV were 93% and 67%. AMH does not appear to be helpful for all subjects with PCOS but may be of some value in those who are anovulatory. However, FNPO was highly sensitive in all phenotypes, and was the single best criterion assessed for all subjects, suggesting the important role of ultrasound.

  18. The influence of dairy consumption and physical activity on ultrasound bone measurements in Flemish children.

    Science.gov (United States)

    De Smet, Stephanie; Michels, Nathalie; Polfliet, Carolien; D'Haese, Sara; Roggen, Inge; De Henauw, Stefaan; Sioen, Isabelle

    2015-03-01

    The study's aim was to analyse whether children's bone status, assessed by calcaneal ultrasound measurements, is influenced by dairy consumption and objectively measured physical activity (PA). Moreover, the interaction between dairy consumption and PA on bone mass was studied. Participants of this cross-sectional study were 306 Flemish children (6-12 years). Body composition was measured with air displacement plethysmography (BodPod), dairy consumption with a Food Frequency Questionnaire, PA with an accelerometer (only in 234 of the 306 children) and bone mass with quantitative ultrasound, quantifying speed of sound (SOS), broadband ultrasound attenuation (BUA) and Stiffness Index (SI). Regression analyses were used to study the associations between dairy consumption, PA, SOS, BUA and SI. Total dairy consumption and non-cheese dairy consumption were positively associated with SOS and SI, but no significant association could be demonstrated with BUA. In contrast, milk consumption, disregarding other dairy products, had no significant effect on calcaneal bone measurements. PA [vigorous PA, moderate to vigorous physical activity (MVPA) and counts per minute] was positively associated and sedentary time was negatively associated with BUA and SI, but no significant influence on SOS could be detected. Dairy consumption and PA (sedentary time and MVPA) did not show any interaction influencing bone measurements. In conclusion, even at young age, PA and dairy consumption positively influence bone mass. Promoting PA and dairy consumption in young children may, therefore, maximize peak bone mass, an important protective factor against osteoporosis later in life.

  19. Hepatic venous pressure gradients measured by duplex ultrasound

    International Nuclear Information System (INIS)

    Tasu, J.-P.; Rocher, L.; Peletier, G.; Kuoch, V.; Kulh, E.; Miquel, A.; Buffet, C.; Biery, M.

    2002-01-01

    AIMS: The hepatic venous pressure gradient is a major prognostic factor in portal hypertension but its measurement is complex and requires invasive angiography. This study investigated the relationship between the hepatic venous pressure gradient and a number of Doppler measurements, including the arterial acceleration index. METHOD: We measured the hepatic venous pressure gradient in 50 fasting patients at hepatic venography. Immediately afterwards, a duplex sonographic examination of the liver was performed at which multiple measurements and indices of the venous and arterial hepatic vasculature were made. RESULTS: Hepatic arterial acceleration was correlated directly with the hepatic venous pressure gradient (r = 0.83, P -2 provided a positive predictive value of 95%, a sensitivity of 65% and a specificity of 95% for detecting patients with severe portal hypertension (hepatic venous pressure gradient > 12 mmHg). A correlation between the hepatic venous pressure gradient and the congestion index of the portal vein velocity (r = 0.45,P = 0.01) and portal vein velocity (r = 0.40,P = 0.044), was also noted. CONCLUSION: Measuring the hepatic arterial acceleration index may help in the non-invasive evaluation of portal hypertension. Tasu, J.-P. et al. (2002)

  20. Hepatic venous pressure gradients measured by duplex ultrasound

    Energy Technology Data Exchange (ETDEWEB)

    Tasu, J.-P.; Rocher, L.; Peletier, G.; Kuoch, V.; Kulh, E.; Miquel, A.; Buffet, C.; Biery, M

    2002-08-01

    AIMS: The hepatic venous pressure gradient is a major prognostic factor in portal hypertension but its measurement is complex and requires invasive angiography. This study investigated the relationship between the hepatic venous pressure gradient and a number of Doppler measurements, including the arterial acceleration index. METHOD: We measured the hepatic venous pressure gradient in 50 fasting patients at hepatic venography. Immediately afterwards, a duplex sonographic examination of the liver was performed at which multiple measurements and indices of the venous and arterial hepatic vasculature were made. RESULTS: Hepatic arterial acceleration was correlated directly with the hepatic venous pressure gradient (r = 0.83, P < 0.0001) and with the Child-Pugh score (r = 0.63, P < 0.0001). An acceleration index cut-off value of 1 m.s{sup -2} provided a positive predictive value of 95%, a sensitivity of 65% and a specificity of 95% for detecting patients with severe portal hypertension (hepatic venous pressure gradient > 12 mmHg). A correlation between the hepatic venous pressure gradient and the congestion index of the portal vein velocity (r = 0.45,P = 0.01) and portal vein velocity (r = 0.40,P = 0.044), was also noted. CONCLUSION: Measuring the hepatic arterial acceleration index may help in the non-invasive evaluation of portal hypertension. Tasu, J.-P. et al. (2002)

  1. Imminent Cardiac Risk Assessment via Optical Intravascular Biochemical Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Wetzel, D.; Wetzel, L; Wetzel, M; Lodder, R

    2009-01-01

    still the first line of defense. However, with the fidelity of 64-slice CT imaging, this technique has recently become an option when the patient presents with symptoms of reduced arterial flow. Single photon emission computerized tomography (SPECT) treadmill exercise testing is a standard non-invasive test for decreased perfusion of heart muscle, but is time consuming and not suited for emergent evaluation. Once the invasive clinical option of catherization is chosen, this provides the opportunity for intravascular ultrasound (IVUS) imaging. As the probe is pulled through the artery, the diameter at different parts is measurable, and monochrome contrast in the constricted area reveals the presence of tissue with a different ultrasonic response. Also, via an optical catheter with a fiber-optic conductor, the possibly of spectroscopic analysis of arterial walls is now a reality. In this case, the optical transducer is coupled to a near-infrared spectrometer. Revealing the arterial chemical health means that plaque vulnerability and imminent risk could be assessed by the physician. The classical emergency use of catherization involves a contrast agent and dynamic X-ray imaging to locate the constriction, determine its severity, and possibly perform angioplasty, and stent placement.

  2. Hemi-Intravascular Stenting for Supermicrosurgical Anastomosis

    OpenAIRE

    Kensuke Tashiro, MD; Shuji Yamashita, MD; Mitsunaga Narushima, MD; Isao Koshima, MD; Shimpei Miyamoto, MD

    2017-01-01

    Background:. Although supermicrosurgical anastomosis is a widely known reconstructive microsurgical technique, it is difficult to perform. To expand the clinical use of supermicrosurgery, we used hemi-intravascular stenting (hemi-IVaS), which is performed by inserting an intravascular stent into one side of the vessel. We conducted lymphaticovenular anastomosis, free perforator flap transfer, and fingertip replantation with supermicrosurgical anastomosis using hemi-IVaS technique and examined...

  3. Non-invasive measurement of pressure gradients using ultrasound

    DEFF Research Database (Denmark)

    Olesen, Jacob Bjerring; Traberg, Marie Sand; Pihl, Michael Johannes

    2013-01-01

    for isotropic fluids to the estimated velocity fields. The velocity fields were measured for a steady flow on a carotid bifurcation phantom (Shelley Medical, Canada) with a 70% constriction on the internal branch. Scanning was performed with a BK8670 linear transducer (BK Medical, Denmark) connected to a BK...

  4. Ultrasound power measurements of HITU transducer with a more stable radiation force balance

    Energy Technology Data Exchange (ETDEWEB)

    Karaboece, B; Sadiko' lu, E; Bilgic, E, E-mail: baki.karaboce@ume.tubitak.gov.t [Tuebitak Ulusal Metroloji Enstituesue (UME), P.K. 54 41470 Gebze-Kocaeli (Turkey)

    2011-02-01

    A new radiation force balance (RFB) system was established at Turkish National Metrology Institute (UME) Ultrasonics Laboratory for High intensity therapeutic ultrasound (HITU) power measurements. The new system is highly stable at high power levels up to 500 Watts. The measurement system consists of a Plexiglas cylindrical balance arm, target mounting scale disks, conical reflecting and absorbing targets, adjustment nuts, and a hanging wire. Both of the two sides of balance were mounted similar size and weight targets. The equilibrium of the balance arm can be adjusted with nuts on screws located at both sides of the balance arm. Transducer was mounted to bottom of water tank. Absorbers in the bottom and the near walls of the tank were used for reflecting target case. Ultrasound power was applied to one scale of the balance where the reflecting/absorbing target was mounted and corresponding force was measured on the other scale of balance where was connected to a balance with a thin wire while the thin rest standing on a support. Ultrasound power of two HITU transducers at frequencies 0.93 MHz, 1.1 MHz and 3.3 MHz were measured with conventional and new system, the values were compared and uncertainty components were assessed in this paper.

  5. Automated 3D ultrasound measurement of the angle of progression in labor.

    Science.gov (United States)

    Montaguti, Elisa; Rizzo, Nicola; Pilu, Gianluigi; Youssef, Aly

    2018-01-01

    To assess the feasibility and reliability of an automated technique for the assessment of the angle of progression (AoP) in labor by using three-dimensional (3D) ultrasound. AoP was assessed by using 3D transperineal ultrasound by two operators in 52 women in active labor to evaluate intra- and interobserver reproducibility. Furthermore, intermethod agreement between automated and manual techniques on 3D images, and between automated technique on 3D vs 2D images were evaluated. Automated measurements were feasible in all cases. Automated measurements were considered acceptable in 141 (90.4%) out of the 156 on the first assessments and in all 156 after repeating measurements for unacceptable evaluations. The automated technique on 3D images demonstrated good intra- and interobserver reproducibility. The 3D-automated technique showed a very good agreement with the 3D manual technique. Notably, AoP calculated with the 3D automated technique were significantly wider in comparison with those measured manually on 3D images (133 ± 17° vs 118 ± 21°, p = 0.013). The assessment of the angle of progression through 3D ultrasound is highly reproducible. However, automated software leads to a systematic overestimation of AoP in comparison with the standard manual technique thus hindering its use in clinical practice in its present form.

  6. Ultrasound power measurements of HITU transducer with a more stable radiation force balance

    International Nuclear Information System (INIS)

    Karaboece, B; Sadiko'lu, E; Bilgic, E

    2011-01-01

    A new radiation force balance (RFB) system was established at Turkish National Metrology Institute (UME) Ultrasonics Laboratory for High intensity therapeutic ultrasound (HITU) power measurements. The new system is highly stable at high power levels up to 500 Watts. The measurement system consists of a Plexiglas cylindrical balance arm, target mounting scale disks, conical reflecting and absorbing targets, adjustment nuts, and a hanging wire. Both of the two sides of balance were mounted similar size and weight targets. The equilibrium of the balance arm can be adjusted with nuts on screws located at both sides of the balance arm. Transducer was mounted to bottom of water tank. Absorbers in the bottom and the near walls of the tank were used for reflecting target case. Ultrasound power was applied to one scale of the balance where the reflecting/absorbing target was mounted and corresponding force was measured on the other scale of balance where was connected to a balance with a thin wire while the thin rest standing on a support. Ultrasound power of two HITU transducers at frequencies 0.93 MHz, 1.1 MHz and 3.3 MHz were measured with conventional and new system, the values were compared and uncertainty components were assessed in this paper.

  7. Central Corneal Thickness Measurement by Ultrasound versus Orbscan II

    Directory of Open Access Journals (Sweden)

    Amir Faramarzi

    2008-12-01

    Full Text Available

    PURPOSE: To compare Orbscan II and ultrasonic pachymetry for measurement of central corneal thickness (CCT in eyes scheduled for keratorefractive surgery. METHODS: CCT was measured using Orbscan II (Bausch & Lomb, USA and then by ultrasonic pachymetry (Tomey SP-3000, Tomey Ltd, Japan in 100 eyes of 100 patients with no history of ocular surgery scheduled for excimer laser refractive surgery. RESULTS: Mean CCT was 544.7±35.5 (range 453-637 µm by ultrasonic pachymetry versus 546.9±41.6 (range 435-648 µm measured by Orbscan II applying an acoustic factor of 0.92 (P=0.14. The standard deviation of measurements was greater with Orbscan pachymetry but the difference was not statistically significant. CONCLUSION: CCT measurements by Orbscan II (applying an acoustic factor and by ultrasonic pachymetry are not significantly different; however, when CCT readings by Orbscan II are in the lower range, it is advisable to recheck the measurements using ultrasonic pachymetry.

  1. Novel approaches to the management of disseminated intravascular coagulation

    NARCIS (Netherlands)

    Levi, M. [=Marcel M.; de Jonge, E.; van der Poll, T.; ten Cate, H.

    2000-01-01

    Disseminated intravascular coagulation (DIC) is a syndrome characterized by systemic intravascular activation of coagulation, leading to widespread deposition of fibrin in the circulation. We addressed the issue of whether there is evidence that this fibrin deposition contributes to multiple organ

  2. Prediction of outcome after femoropopliteal balloon angioplasty by intravascular ultrasound

    DEFF Research Database (Denmark)

    Vogt, K C; Just, S; Rasmussen, John Bøje Grønvall

    1997-01-01

    limbs) undergoing PTA of the superficial femoral or popliteal artery. The degree of stenosis, the diameter and area of the lumen and the morphological changes in the plaque were related to the short-term patency of the intervention, as evaluated by duplex scan and ankle branchial index. RESULTS: Fifteen...... arteries remained patent. Two occlusions and two stenoses developed during the first 3 months after the intervention and one occlusion occurred after 1 year. The following IVUS parameters were related to a favourable patency: presence of calcification; dissection or plaque rupture and residual stenosis...

  3. Intravascular ultrasound for iliac artery imaging. Clinical review

    DEFF Research Database (Denmark)

    Vogt, K G; Schroeder, T V

    2001-01-01

    IVUS is able to produce trans-sectional images of the iliac arteries at a high resolution. The three layered appearance of the arterial wall can be visualized. In the atherosclerotic diseased artery calcified plaques can be discerned from non-calcified plaques, and the distribution of the plaque...

  4. Fluorescent Method for Observing Intravascular Bonghan Duct

    Directory of Open Access Journals (Sweden)

    Byung-Cheon Lee

    2005-12-01

    Full Text Available Observation of intra-vascular threadlike structures in the blood vessels of rats is reported with the images by differential interference contrast microscope, and fluorescence inverted microscope of the acridine-orange stained samples. The confocal microscope image and the hematoxylin-eosin staining revealed the distinctive pattern of nuclei distribution that clearly discerned the threadlike structure from fibrin, capillary, small venule, arteriole, or lymph vessel. Physiological function of the intra-vascular thread in connection with acupuncture is discussed. Especially, this threadlike duct can be a circulation path for herb-liquid flow, which may provide the scientific mechanism for therapeutic effect of herbal acupuncture.

  5. Automated kidney morphology measurements from ultrasound images using texture and edge analysis

    Science.gov (United States)

    Ravishankar, Hariharan; Annangi, Pavan; Washburn, Michael; Lanning, Justin

    2016-04-01

    In a typical ultrasound scan, a sonographer measures Kidney morphology to assess renal abnormalities. Kidney morphology can also help to discriminate between chronic and acute kidney failure. The caliper placements and volume measurements are often time consuming and an automated solution will help to improve accuracy, repeatability and throughput. In this work, we developed an automated Kidney morphology measurement solution from long axis Ultrasound scans. Automated kidney segmentation is challenging due to wide variability in kidney shape, size, weak contrast of the kidney boundaries and presence of strong edges like diaphragm, fat layers. To address the challenges and be able to accurately localize and detect kidney regions, we present a two-step algorithm that makes use of edge and texture information in combination with anatomical cues. First, we use an edge analysis technique to localize kidney region by matching the edge map with predefined templates. To accurately estimate the kidney morphology, we use textural information in a machine learning algorithm framework using Haar features and Gradient boosting classifier. We have tested the algorithm on 45 unseen cases and the performance against ground truth is measured by computing Dice overlap, % error in major and minor axis of kidney. The algorithm shows successful performance on 80% cases.

  6. Why Have So Many Intravascular Glucose Monitoring Devices Failed?

    Science.gov (United States)

    Smith, John L; Rice, Mark J

    2015-07-01

    Secondary to the inherent limitations of both point-of-care and central laboratory glucose technologies, continuous glucose measurement has recently enjoyed a high level of investment. Because of the perceived advantages by some of measuring in the intravascular space compared to the subcutaneous tissue, a number of technologies have been developed. In this review, we evaluate nine systems that have shown promise, although only one of these has been cleared for sale in the United States. The detection methodology, regulatory status, technical issues, and company circumstance surrounding each technology are examined. © 2015 Diabetes Technology Society.

  7. Prostate Ultrasound

    Medline Plus

    Full Text Available ... with measurements acquired as needed for any treatment planning. detect an abnormal growth within the prostate. help ... end of their bowel (rectum) removed during prior surgery are not good candidates for ultrasound of the ...

  8. Prostate Ultrasound

    Medline Plus

    Full Text Available ... is enlarged, also known as benign prostatic hyperplasia (BPH) , with measurements acquired as needed for any treatment ... caption Related Articles and Media Benign Prostatic Hyperplasia (BPH) (Enlargement of the Prostate) Prostate Cancer Ultrasound- and ...

  9. Prostate Ultrasound

    Medline Plus

    Full Text Available ... also known as benign prostatic hyperplasia (BPH) , with measurements acquired as needed for any treatment planning. detect ... areas of the body while other areas, especially air-filled lungs, are poorly suited for ultrasound. For ...

  10. Ultrasound -- Pelvis

    Medline Plus

    Full Text Available ... Ultrasound - Abdomen Obstetric Ultrasound Ultrasound - Prostate Kidney and Bladder Stones Abnormal Vaginal Bleeding Ovarian Cancer Images related to Ultrasound - Pelvis Sponsored by Please ...

  11. Ultrasound -- Pelvis

    Medline Plus

    Full Text Available ... Children's (Pediatric) Ultrasound - Abdomen Obstetric Ultrasound Ultrasound - Prostate Kidney and Bladder Stones Abnormal Vaginal Bleeding Ovarian Cancer Images related to Ultrasound - Pelvis Sponsored by Please ...

  12. Ultrasound -- Pelvis

    Medline Plus

    Full Text Available ... specific content. Related Articles and Media Sonohysterography Ultrasound - Abdomen Children's (Pediatric) Ultrasound - Abdomen Obstetric Ultrasound Ultrasound - Prostate Kidney and ...

  13. Intra and interobserver variability of renal allograft ultrasound volume and resistive index measurements

    International Nuclear Information System (INIS)

    Mancini, Marcello; Liuzzi, Raffaele; Daniele, Stefania; Raffio, Teresa; Salvatore, Marco; Sabbatini, Massimo; Cianciaruso, Bruno; Ferrara, Liberato Aldo

    2005-01-01

    Purpose: Aim of the presents study was to evaluate the repeatability and reproducibility of the Doppler Resistive Index (R.I.) and the Ultrasound renal volume measurement in renal transplants. Materials and methods: Twenty -six consecutive patients (18 men, 8 women) mean age of 42,8±12,4 years (M±SD)(range 22-65 years) were studied twice by each of two trained sonographers using a color Doppler ultrasound scanner. Twelve of them had a normal allograft function (defined as stable serum creatinine levels ≤123,76 μmol/L), whilst the remaining 14 had decreased allograft function (serum creatinine 132.6-265.2 μmol/L). Results were given as mean of 6 measurements performed at upper, middle and lower pole of the kidney. Intra- and interobserver variability was assessed by the repeatability coefficient and coefficient of variation (CV). Results: Regarding Resistive Index measurement, repeatability coefficient was between 0.04 and 0.06 and the coefficient of variation was [it

  14. Ultrasound imaging measurement of submerged topography in the muddy water physical model

    International Nuclear Information System (INIS)

    Xiao, Xiongwu; Guo, Bingxuan; Li, Deren; Zhang, Peng; Zang, Yu-fu; Zou, Xianjian; Liu, Jian-chen

    2015-01-01

    The real-time, accurate measurement of submerged topography is vital for the analysis of riverbed erosion and deposition. This paper describes a novel method of measuring submerged topography in the B-scan image obtained using an ultrasound imaging device. Results show the distribution of gray values in the image has a process of mutation. This mutation process can be used to adaptively track the topographic lines between riverbed and water, based on the continuity of topography in the horizontal direction. The extracted topographic lines, of one pixel width, are processed by a wavelet filtering method. Compared with the actual topography, the measurement accuracy is within 1 mm. It is suitable for the real-time measurement and analysis of all current model topographies with the advantage of good self-adaptation. In particular, it is visible and intuitive for muddy water in the movable-bed model experiment. (paper)

  15. Validation of ultrasound as a noninvasive tool to measure subcutaneous fat depth in leatherback sea turtles (Dermochelys coriacea)

    Science.gov (United States)

    Harris, Heather S.; Benson, Scott R.; James, Michael C.; Martin, Kelly J.; Stacy, Brian A.; Daoust, Pierre-Yves; Rist, Paul M.; Work, Thierry M.; Balazs, George H.; Seminoff, Jeffrey A.

    2016-01-01

    Leatherback turtles (Dermochelys coriacea) undergo substantial cyclical changes in body condition between foraging and nesting. Ultrasonography has been used to measure subcutaneous fat as an indicator of body condition in many species but has not been applied in sea turtles. To validate this technique in leatherback turtles, ultrasound images were obtained from 36 live-captured and dead-stranded immature and adult turtles from foraging and nesting areas in the Pacific and Atlantic oceans. Ultrasound measurements were compared with direct measurements from surgical biopsy or necropsy. Tissue architecture was confirmed histologically in a subset of turtles. The dorsal shoulder region provided the best site for differentiation of tissues. Maximum fat depth values with the front flipper in a neutral (45–90°) position demonstrated good correlation with direct measurements. Ultrasound-derived fat measurements may be used in the future for quantitative assessment of body condition as an index of health in this critically endangered species.

  16. VALIDATION OF ULTRASOUND AS A NONINVASIVE TOOL TO MEASURE SUBCUTANEOUS FAT DEPTH IN LEATHERBACK SEA TURTLES (DERMOCHELYS CORIACEA).

    Science.gov (United States)

    Harris, Heather S; Benson, Scott R; James, Michael C; Martin, Kelly J; Stacy, Brian A; Daoust, Pierre-Yves; Rist, Paul M; Work, Thierry M; Balazs, George H; Seminoff, Jeffrey A

    2016-03-01

    Leatherback turtles (Dermochelys coriacea) undergo substantial cyclical changes in body condition between foraging and nesting. Ultrasonography has been used to measure subcutaneous fat as an indicator of body condition in many species but has not been applied in sea turtles. To validate this technique in leatherback turtles, ultrasound images were obtained from 36 live-captured and dead-stranded immature and adult turtles from foraging and nesting areas in the Pacific and Atlantic oceans. Ultrasound measurements were compared with direct measurements from surgical biopsy or necropsy. Tissue architecture was confirmed histologically in a subset of turtles. The dorsal shoulder region provided the best site for differentiation of tissues. Maximum fat depth values with the front flipper in a neutral (45-90°) position demonstrated good correlation with direct measurements. Ultrasound-derived fat measurements may be used in the future for quantitative assessment of body condition as an index of health in this critically endangered species.

  17. Quinine-induced disseminated intravascular coagulation.

    Science.gov (United States)

    Spearing, R L; Hickton, C M; Sizeland, P; Hannah, A; Bailey, R R

    Recurrent disseminated intravascular coagulation occurred in 3 women after ingestion of quinine tablets for cramp. All had circulating quinine-dependent antibodies to platelets and in 2 there was initial evidence of antibody consumption, with low titres that rose steeply over the next few days and remained high for many months.

  18. Intravascular volume after aneurysmal subarachnoid hemorrhage

    NARCIS (Netherlands)

    Hoff, R.G.

    2009-01-01

    Intravascular volume after aneurysmal subarachnoid hemorrhage A subarachnoid hemorrhage (SAH) from a ruptured cerebral aneurysm is a devastating disorder with an often poor prognosis. The occurrence of delayed cerebral ischemia (DCI) is one of the most important factors determining outcome in

  19. Disseminated Intravascular Coagulation Following Induction of ...

    African Journals Online (AJOL)

    Background: Disseminated Intravascular coagulopathy (DIC) has been reported following use of Misoprostol which is an old drug with new indications in Obstetrics and. Gynecology. Its effectiveness, low cost, stability in tropical conditions and ease of administration as well as side effects like gastrointestinal effect, uterine ...

  20. Hemi-Intravascular Stenting for Supermicrosurgical Anastomosis

    Directory of Open Access Journals (Sweden)

    Kensuke Tashiro, MD

    2017-11-01

    Conclusions:. Hemi-IVaS could be a useful alternative to conventional intravascular stenting techniques and is also effective for supermicrosurgical perforator-to-perforator anastomosis. Further studies are needed to improve the success rate and to explore its other possible utilizations in supermicrosurgery.

  1. Brachial artery vasomotion and transducer pressure effect on measurements by active contour segmentation on ultrasound

    Energy Technology Data Exchange (ETDEWEB)

    Cary, Theodore W.; Sultan, Laith R.; Sehgal, Chandra M., E-mail: sehgalc@uphs.upenn.edu [Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States); Reamer, Courtney B.; Mohler, Emile R. [Department of Medicine, Division of Cardiovascular Medicine, Section of Vascular Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States)

    2014-02-15

    Purpose: To use feed-forward active contours (snakes) to track and measure brachial artery vasomotion on ultrasound images recorded in both transverse and longitudinal views; and to compare the algorithm's performance in each view. Methods: Longitudinal and transverse view ultrasound image sequences of 45 brachial arteries were segmented by feed-forward active contour (FFAC). The segmented regions were used to measure vasomotion artery diameter, cross-sectional area, and distention both as peak-to-peak diameter and as area. ECG waveforms were also simultaneously extracted frame-by-frame by thresholding a running finite-difference image between consecutive images. The arterial and ECG waveforms were compared as they traced each phase of the cardiac cycle. Results: FFAC successfully segmented arteries in longitudinal and transverse views in all 45 cases. The automated analysis took significantly less time than manual tracing, but produced superior, well-behaved arterial waveforms. Automated arterial measurements also had lower interobserver variability as measured by correlation, difference in mean values, and coefficient of variation. Although FFAC successfully segmented both the longitudinal and transverse images, transverse measurements were less variable. The cross-sectional area computed from the longitudinal images was 27% lower than the area measured from transverse images, possibly due to the compression of the artery along the image depth by transducer pressure. Conclusions: FFAC is a robust and sensitive vasomotion segmentation algorithm in both transverse and longitudinal views. Transverse imaging may offer advantages over longitudinal imaging: transverse measurements are more consistent, possibly because the method is less sensitive to variations in transducer pressure during imaging.

  2. Numerical Calculation and Measurement of Nonlinear Acoustic Fields in Ultrasound Diagnosis

    Science.gov (United States)

    Kawagishi, Tetsuya; Saito, Shigemi; Mine, Yoshitaka

    2002-05-01

    In order to develop a tool for designing on the ultrasonic probe and its peripheral devices for tissue-harmonic-imaging systems, a study is carried out to compare the calculation and observation results of nonlinear acoustic fields for a diagnostic ultrasound system. The pulsed ultrasound with a center frequency of 2.5 MHz is emanated from a weakly focusing sector probe with a 6.5 mm aperture radius and a 50 mm focal length into an agar phantom with an attenuation coefficient of about 0.6 dB/cm/MHz or 1.2 dB/cm/MHz. The nonlinear acoustic field is measured using a needle-type hydrophone. The calculation is based on the Khokhlov-Zabolotskaya-Kuznetsov(KZK) equation which is modified so that the frequency dependence of the attenuation coefficient is the same as that in biological tissue. This equation is numerically solved with the implicit backward method employing the iterative method. The measured and calculated amplitude spectra show good agreement with each other.

  3. Acousto-optic measurements of ultrasound attenuation in tellurium dioxide crystal

    International Nuclear Information System (INIS)

    Voloshinov, V. B.; Lemyaskina, E. A.

    1996-01-01

    The paper is devoted to experimental investigation of ultrasound propagation in tellurium dioxide monocrystal. In particular, attenuation of slow shear acoustic modes in the crystal was measured. The measurements were performed by acousto-optic methods using probing of acoustic column by a laser beam. The paper describes measurements of acoustic attenuation coefficient for slow shear ultrasonic waves propagating at an angle =4.5 O with respect to the (110) direction in the (110) plane. The investigation was made at acoustic frequency f = 100 MHz with pulsed acoustic waves and with an optical beam of a He-Ne laser. It is found that the attenuation coefficient is α = 0.57 cm -1 ± 15 %. The attenuation at acoustic frequencies f ≥ 100 MHz influences performance characteristics of acousto-optical devices based on tellurium dioxide. As proved, spectral resolution of a quasicollinear acoustooptic filter decreases by a factor of 2 compared to a case of the attenuation absence. (authors)

  4. Ultrasound-assisted extraction for total sulphur measurement in mine tailings

    Energy Technology Data Exchange (ETDEWEB)

    Khan, Adnan Hossain, E-mail: ad_li2@yahoo.com [Department of Civil and Environmental Engineering, University of Western Ontario (Canada); Shang, Julie Q.; Alam, Raquibul [Department of Civil and Environmental Engineering, University of Western Ontario (Canada)

    2012-10-15

    Highlights: Black-Right-Pointing-Pointer We develop a total sulphur measuring procedure of mine tailings. Black-Right-Pointing-Pointer Ultrasound is used in the sample pre-treatment process. Black-Right-Pointing-Pointer Full factorial design is applied to identify the best level of effecting factors. - Abstract: A sample preparation method for percentage recovery of total sulphur (%S) in reactive mine tailings based on ultrasound-assisted digestion (USAD) and inductively coupled plasma-optical emission spectroscopy (ICP-OES) was developed. The influence of various methodological factors was screened by employing a two-level and three-factor (2{sup 3}) full factorial design and using KZK-1, a sericite schist certified reference material (CRM), to find the optimal combination of studied factors and %S. Factors such as the sonication time, temperature and acid combination were studied, with the best result identified as 20 min of sonication, 80 Degree-Sign C temperature and 1 ml of HNO{sub 3}:1 ml of HCl, which can achieve 100% recovery for the selected CRM. Subsequently a fraction of the 2{sup 3} full factorial design was applied to mine tailings. The percentage relative standard deviation (%RSD) for the ultrasound method is less than 3.0% for CRM and less than 6% for the mine tailings. The investigated method was verified by X-ray diffraction analysis. The USAD method compared favorably with existing methods such as hot plate assisted digestion method, X-ray fluorescence and LECO Trade-Mark-Sign -CNS method.

  5. Intra- and interobserver reliability of quantitative ultrasound measurement of the plantar fascia.

    Science.gov (United States)

    Rathleff, Michael Skovdal; Moelgaard, Carsten; Lykkegaard Olesen, Jens

    2011-01-01

    To determine intra- and interobserver reliability and measurement precision of sonographic assessment of plantar fascia thickness when using one, the mean of two, or the mean of three measurements. Two experienced observers scanned 20 healthy subjects twice with 60 minutes between test and retest. A GE LOGIQe ultrasound scanner was used in the study. The built-in software in the scanner was used to measure the thickness of the plantar fascia (PF). Reliability was calculated using intraclass correlation coefficient (ICC) and limits of agreement (LOA). Intraobserver reliability (ICC) using one measurement was 0.50 for one observer and 0.52 for the other, and using the mean of three measurements intraobserver reliability increased up to 0.77 and 0.67, respectively. Interobserver reliability (ICC) when using one measurement was 0.62 and increased to 0.82 when using the average of three measurements. LOA showed that when using the average of three measurements, LOA decreased to 0.6 mm, corresponding to 17.5% of the mean thickness of the PF. The results showed that reliability increases when using the mean of three measurements compared with one. Limits of agreement based on intratester reliability shows that changes in thickness that are larger than 0.6 mm can be considered actual changes in thickness and not a result of measurement error. Copyright © 2011 Wiley Periodicals, Inc.

  6. What is the value of ultrasound soft tissue measurements in the prediction of abnormal fetal growth?

    LENUS (Irish Health Repository)

    Farah, N

    2012-02-01

    Abnormal fetal growth increases the complications of pregnancy not only for the baby but also for the mother. Growth abnormalities also have lifelong consequences. These babies are at increased risk of insulin resistance, diabetes and hypertension later in life. It is important to identify these babies antenatally to optimise their clinical care. Although used extensively antenatally to monitor fetal growth, ultrasound has its limitations. Despite the use of more than 50 different formulae to estimate fetal weight, their performance has been poor at the extremes of fetal weight. Over the past 20 years there has been emerging interest in studying fetal soft tissue measurements to improve detection of growth abnormalities. This review paper outlines the value of soft tissue measurements in identifying fetal growth abnormalities, in estimating fetal weight and in managing diabetes mellitus in pregnancy.

  7. Prostate Ultrasound

    Medline Plus

    Full Text Available ... Physician Resources Professions Site Index A-Z Ultrasound - Prostate Ultrasound of the prostate uses sound waves to ... Ultrasound Imaging? What is Ultrasound Imaging of the Prostate? Ultrasound is safe and painless, and produces pictures ...

  8. Volume measurement variability in three-dimensional high-frequency ultrasound images of murine liver metastases

    International Nuclear Information System (INIS)

    Wirtzfeld, L A; Graham, K C; Groom, A C; MacDonald, I C; Chambers, A F; Fenster, A; Lacefield, J C

    2006-01-01

    The identification and quantification of tumour volume measurement variability is imperative for proper study design of longitudinal non-invasive imaging of pre-clinical mouse models of cancer. Measurement variability will dictate the minimum detectable volume change, which in turn influences the scheduling of imaging sessions and the interpretation of observed changes in tumour volume. In this paper, variability is quantified for tumour volume measurements from 3D high-frequency ultrasound images of murine liver metastases. Experimental B16F1 liver metastases were analysed in different size ranges including less than 1 mm 3 , 1-4 mm 3 , 4-8 mm 3 and 8-70 mm 3 . The intra- and inter-observer repeatability was high over a large range of tumour volumes, but the coefficients of variation (COV) varied over the volume ranges. The minimum and maximum intra-observer COV were 4% and 14% for the 1-4 mm 3 and 3 tumours, respectively. For tumour volumes measured by segmenting parallel planes, the maximum inter-slice distance that maintained acceptable measurement variability increased from 100 to 600 μm as tumour volume increased. Comparison of free breathing versus ventilated animals demonstrated that respiratory motion did not significantly change the measured volume. These results enable design of more efficient imaging studies by using the measured variability to estimate the time required to observe a significant change in tumour volume

  9. Reliability of ultrasound thickness measurement of the abdominal muscles during clinical isometric endurance tests.

    Science.gov (United States)

    ShahAli, Shabnam; Arab, Amir Massoud; Talebian, Saeed; Ebrahimi, Esmaeil; Bahmani, Andia; Karimi, Noureddin; Nabavi, Hoda

    2015-07-01

    The study was designed to evaluate the intra-examiner reliability of ultrasound (US) thickness measurement of abdominal muscles activity when supine lying and during two isometric endurance tests in subjects with and without Low back pain (LBP). A total of 19 women (9 with LBP, 10 without LBP) participated in the study. Within-day reliability of the US thickness measurements at supine lying and the two isometric endurance tests were assessed in all subjects. The intra-class correlation coefficient (ICC) was used to assess the relative reliability of thickness measurement. The standard error of measurement (SEM), minimal detectable change (MDC) and the coefficient of variation (CV) were used to evaluate the absolute reliability. Results indicated high ICC scores (0.73-0.99) and also small SEM and MDC scores for within-day reliability assessment. The Bland-Altman plots of agreement in US measurement of the abdominal muscles during the two isometric endurance tests demonstrated that 95% of the observations fall between the limits of agreement for test and retest measurements. Together the results indicate high intra-tester reliability for the US measurement of the thickness of abdominal muscles in all the positions tested. According to the study's findings, US imaging can be used as a reliable method for assessment of abdominal muscles activity in supine lying and the two isometric endurance tests employed, in participants with and without LBP. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. The challenges of measuring in vivo knee collateral ligament strains using ultrasound.

    Science.gov (United States)

    Slane, Laura C; Slane, Josh A; D'hooge, Jan; Scheys, Lennart

    2017-08-16

    Ultrasound-based methods have shown promise in their ability to characterize non-uniform deformations in large energy-storing tendons such as the Achilles and patellar tendons, yet applications to other areas of the body have been largely unexplored. The noninvasive quantification of collateral ligament strain could provide an important clinical metric of knee frontal plane stability, which is relevant in ligament injury and for measuring outcomes following total knee arthroplasty. In this pilot cadaveric experiment, we investigated the possibility of measuring collateral ligament strain with our previously validated speckle-tracking approach, but encountered a number of challenges during both data acquisition and processing. Given the clinical interest in this type of tool, and the fact that this is a developing area of research, the goal of this article is to transparently describe this pilot study, both in terms of methods and results, while also identifying specific challenges to this work and areas for future study. Some challenges faced relate generally to speckle-tracking of soft tissues (e.g. the limitations of using a 2D imaging modality to characterize 3D motion), while others are specific to this application (e.g. the small size and complex anatomy of the collateral ligaments). This work illustrates a clear need for additional studies, particularly relating to the collection of ground-truth data and more thorough validation work. These steps will be critical prior to the translation of ultrasound-based measures of collateral ligament strains into the clinic. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Ultrasound imaging

    International Nuclear Information System (INIS)

    Wells, P.N.T.

    1983-01-01

    Ultrasound is a form of energy which consists of mechanical vibrations the frequencies of which are so high that they are above the range of human hearing. The lower frequency limit of the ultrasonic spectrum may generally be taken to be about 20 kHz. Most biomedical applications of ultrasound employ frequencies in the range 1-15 MHz. At these frequencies, the wavelength is in the range 1.5 - 0.1 mm in soft tissues, and narrow beams of ultrasound can be generated which propagate through such tissues without excessive attenuation. This chapter begins with brief reviews of the physics of diagnostic ultrasound pulse-echo imaging methods and Doppler imaging methods. The remainder of the chapter is a resume of the applications of ultrasonic imaging to physiological measurement

  12. General Ultrasound Imaging

    Medline Plus

    Full Text Available ... size, shape and consistency (whether the object is solid or filled with fluid). In medicine, ultrasound is ... ultrasound, measures the direction and speed of blood cells as they move through vessels. The movement of ...

  13. General Ultrasound Imaging

    Medline Plus

    Full Text Available ... may produce minimal discomfort. If a Doppler ultrasound study is performed, you may actually hear pulse-like sounds that change in pitch as the blood flow is monitored and measured. Most ultrasound examinations ...

  14. Medical Ultrasound Imaging.

    Science.gov (United States)

    Hughes, Stephen

    2001-01-01

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

  15. Ultrasound-based measurement of liquid-layer thickness: A novel time-domain approach

    Science.gov (United States)

    Praher, Bernhard; Steinbichler, Georg

    2017-01-01

    Measuring the thickness of a thin liquid layer between two solid materials is important when the adequate separation of metallic parts by a lubricant film (e.g., in bearings or mechanical seals) is to be assessed. The challenge in using ultrasound-based systems for such measurements is that the signal from the liquid layer is a superposition of multiple reflections. We have developed an algorithm for reconstructing this superimposed signal in the time domain. By comparing simulated and measured signals, the time-of-flight of the ultrasonic pulse in a layer can be estimated. With the longitudinal sound velocity known, the layer thickness can then be calculated. In laboratory measurements, we validate successfully (maximum relative error 4.9%) our algorithm for layer thicknesses ranging from 30 μm to 200 μm. Furthermore, we tested our method in the high-temperature environment of polymer processing by measuring the clearance between screw and barrel in the plasticisation unit of an injection moulding machine. The results of such measurements can indicate (i) the wear status of the tribo-mechanical screw-barrel system and (ii) unsuitable process conditions.

  16. Development of a method for measuring femoral torsion using real-time ultrasound

    International Nuclear Information System (INIS)

    Hafiz, Eliza; Hiller, Claire E; Nightingale, E Jean; Eisenhuth, John P; Refshauge, Kathryn M; Nicholson, Leslie L; Clarke, Jillian L; Grimaldi, Alison

    2014-01-01

    Excessive femoral torsion has been associated with various musculoskeletal and neurological problems. To explore this relationship, it is essential to be able to measure femoral torsion in the clinic accurately. Computerized tomography (CT) and magnetic resonance imaging (MRI) are thought to provide the most accurate measurements but CT involves significant radiation exposure and MRI is expensive. The aim of this study was to design a method for measuring femoral torsion in the clinic, and to determine the reliability of this method. Details of design process, including construction of a jig, the protocol developed and the reliability of the method are presented. The protocol developed used ultrasound to image a ridge on the greater trochanter, and a customized jig placed on the femoral condyles as reference points. An inclinometer attached to the customized jig allowed quantification of the degree of femoral torsion. Measurements taken with this protocol had excellent intra- and inter-rater reliability (ICC 2,1  = 0.98 and 0.97, respectively). This method of measuring femoral torsion also permitted measurement of femoral torsion with a high degree of accuracy. This method is applicable to the research setting and, with minor adjustments, will be applicable to the clinical setting. (paper)

  17. Techniques for Intravascular Foreign Body Retrieval

    International Nuclear Information System (INIS)

    Woodhouse, Joe B.; Uberoi, Raman

    2013-01-01

    As endovascular therapies increase in frequency, the incidence of lost or embolized foreign bodies is increasing. The presence of an intravascular foreign body (IFB) is well recognized to have the potential to cause serious complications. IFB can embolize and impact critical sites such as the heart, with subsequent significant morbidity or mortality. Intravascular foreign bodies most commonly result from embolized central line fragments, but they can originate from many sources, both iatrogenic and noniatrogenic. The percutaneous approach in removing an IFB is widely perceived as the best way to retrieve endovascular foreign bodies. This minimally invasive approach has a high success rate with a low associated morbidity, and it avoids the complications related to open surgical approaches. We examined the characteristics, causes, and incidence of endovascular embolizations and reviewed the various described techniques that have been used to facilitate subsequent explantation of such materials

  18. Reliability and Validity of Ultrasound Cross Sectional Area Measurements for Long-Duration Spaceflight

    Science.gov (United States)

    Scott, Jessica M.; Martin, David S.; Cunningham, David; Matz, Timothy; Caine, Timothy; Hackney, Kyle J.; Arzeno, Natalia; Ploutz-Snyder, Lori

    2010-01-01

    Limb muscle atrophy and the accompanying decline in function can adversely affect the performance of astronauts during mission-related activities and upon re-ambulation in a gravitational environment. Previous characterization of space flight-induced muscle atrophy has been performed using pre and post flight magnetic resonance imaging (MRI). In addition to being costly and time consuming, MRI is an impractical methodology for assessing in-flight changes in muscle size. Given the mobility of ultrasound (US) equipment, it may be more feasible to evaluate changes in muscle size using this technique. PURPOSE: To examine the reliability and validity of using a customized template to acquire panoramic ultrasound (US) images for determining quadriceps and gastrocnemius anatomical cross sectional area (CSA). METHODS: Vastus lateralis (VL), rectus femoris (RF), medial gastrocnemius (MG), and lateral gastrocnemius (LG) CSA were assessed in 10 healthy individuals (36+/-2 yrs) using US and MRI. Panoramic US images were acquired by 2 sonographers using a customized template placed on the thigh and calf and analyzed by the same 2 sonographers (CX50 Philips). MRI images of the leg were acquired while subjects were supine in a 1.5T scanner (Signa Horizon LX, General Electric) and were analyzed by 3 trained investigators. The average of the 2 US and 3 MRI values were used for validity analysis. RESULTS: High inter-experimenter reliability was found for both the US template and MRI analysis as coefficients of variation across muscles ranged from 2.4 to 4.1% and 2.8 to 3.8%, respectively. Significant correlations were found between US and MRI CSA measures (VL, r = 0.85; RF, r = 0.60; MG, r = 0.86; LG, r = 0.73; p reliable measures of leg muscle CSA, and thus could be used to characterize changes in muscle CSA both in flight and on the ground.

  19. Fluorescent Method for Observing Intravascular Bonghan Duct

    OpenAIRE

    Byung-Cheon Lee; Ku Youn Baik; Hyeon-Min Johng; Baekkyoung Sung; Kyung Soon Soh; Dae-In Kang; Kwang-Sup Soh

    2005-01-01

    Observation of intra-vascular threadlike structures in the blood vessels of rats is reported with the images by differential interference contrast microscope, and fluorescence inverted microscope of the acridine-orange stained samples. The confocal microscope image and the hematoxylin-eosin staining revealed the distinctive pattern of nuclei distribution that clearly discerned the threadlike structure from fibrin, capillary, small venule, arteriole, or lymph vessel. Physiological function of ...

  20. 3D thoracoscopic ultrasound volume measurement validation in an ex vivo and in vivo porcine model of lung tumours

    International Nuclear Information System (INIS)

    Hornblower, V D M; Yu, E; Fenster, A; Battista, J J; Malthaner, R A

    2007-01-01

    The purpose of this study was to validate the accuracy and reliability of volume measurements obtained using three-dimensional (3D) thoracoscopic ultrasound (US) imaging. Artificial 'tumours' were created by injecting a liquid agar mixture into spherical moulds of known volume. Once solidified, the 'tumours' were implanted into the lung tissue in both a porcine lung sample ex vivo and a surgical porcine model in vivo. 3D US images were created by mechanically rotating the thoracoscopic ultrasound probe about its long axis while the transducer was maintained in close contact with the tissue. Volume measurements were made by one observer using the ultrasound images and a manual-radial segmentation technique and these were compared with the known volumes of the agar. In vitro measurements had average accuracy and precision of 4.76% and 1.77%, respectively; in vivo measurements had average accuracy and precision of 8.18% and 1.75%, respectively. The 3D thoracoscopic ultrasound can be used to accurately and reproducibly measure 'tumour' volumes both in vivo and ex vivo

  1. 3D thoracoscopic ultrasound volume measurement validation in an ex vivo and in vivo porcine model of lung tumours

    Energy Technology Data Exchange (ETDEWEB)

    Hornblower, V D M [Canadian Surgical Technologies and Advanced Robotics, London, Ontario (Canada); Yu, E [Canadian Surgical Technologies and Advanced Robotics, London, Ontario (Canada); Fenster, A [Canadian Surgical Technologies and Advanced Robotics, London, Ontario (Canada); Battista, J J [Canadian Surgical Technologies and Advanced Robotics, London, Ontario (Canada); Malthaner, R A [Canadian Surgical Technologies and Advanced Robotics, London, Ontario (Canada)

    2007-01-07

    The purpose of this study was to validate the accuracy and reliability of volume measurements obtained using three-dimensional (3D) thoracoscopic ultrasound (US) imaging. Artificial 'tumours' were created by injecting a liquid agar mixture into spherical moulds of known volume. Once solidified, the 'tumours' were implanted into the lung tissue in both a porcine lung sample ex vivo and a surgical porcine model in vivo. 3D US images were created by mechanically rotating the thoracoscopic ultrasound probe about its long axis while the transducer was maintained in close contact with the tissue. Volume measurements were made by one observer using the ultrasound images and a manual-radial segmentation technique and these were compared with the known volumes of the agar. In vitro measurements had average accuracy and precision of 4.76% and 1.77%, respectively; in vivo measurements had average accuracy and precision of 8.18% and 1.75%, respectively. The 3D thoracoscopic ultrasound can be used to accurately and reproducibly measure 'tumour' volumes both in vivo and ex vivo.

  2. Plantar fasciitis (fasciosis) treatment outcome study: plantar fascia thickness measured by ultrasound and correlated with patient self-reported improvement.

    Science.gov (United States)

    Fabrikant, Jerry M; Park, Tae Soon

    2011-06-01

    Ultrasound, well recognized as an effective diagnostic tool, reveals a thickening of the plantar fascia in patients with plantar fasciitis/fasciosis disease. The authors hypothesized that ultrasound would also reveal a decrease in the plantar fascia thickness for patients undergoing treatment for the disease, a hypothesis that, heretofore, had been only tested on a limited number of subjects. They conducted a more statistically significant study that found that clinical treatment with injection and biomechanical correction does indeed diminish plantar fascia thickness as shown on ultrasound. The study also revealed that patients experience the most heightened plantar fascia tenderness toward the end of the day, and improvement in their symptomatic complaints were associated with a reduction in plantar fascia thickness. As a result, the authors conclude that office-based ultrasound can help diagnose and confirm plantar fasciitis/fasciosis through the measurement of the plantar fascia thickness. Because of the advantages of ultrasound--that it is non-invasive with greater patient acceptance, cost effective and radiation-free--the imaging tool should be considered and implemented early in the diagnosis and treatment of plantar fasciitis/fasciosis. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. Non-invasive Estimation of Pressure Changes using 2-D Vector Velocity Ultrasound: An Experimental Study with In-Vivo Examples

    DEFF Research Database (Denmark)

    Olesen, Jacob Bjerring; Villagómez Hoyos, Carlos Armando; Møller, Niclas Dechau

    2018-01-01

    and at the aortic valve of two healthy volunteers. Ultrasound measurements were performed using the experimental scanner SARUS, in combination with an 8MHz linear array transducer for experimental scans and a carotid scan, whereas a 3.5MHz phased array probe was employed for a scan of an aortic valve. Measured 2-D......A non-invasive method for estimating intravascular pressure changes using 2-D vector velocity is presented. The method was first validated on computational fluid dynamics (CFD) data, and with catheter measurements on phantoms. Hereafter, the method was tested in-vivo at the carotid bifurcation...

  4. Carotid and femoral B-mode ultrasound intima-media thickness measurements in adult post-coarctectomy patients

    NARCIS (Netherlands)

    Vriend, J. J. W.; de Groot, E.; Kastelein, J. J. P.; Mulder, B. J. M.

    2004-01-01

    Aim. Cardiovascular and cerebrovascular morbidity and mortality in adult post-coarctectomy patients is increased even after successful surgical repair of the aorta. B-mode ultrasound intima-media thickness (IMT), a validated marker for atherosclerosis and vascular disease risk, was used to measure

  5. An Implantable Intravascular Pressure Sensor for a Ventricular Assist Device

    Directory of Open Access Journals (Sweden)

    Luigi Brancato

    2016-08-01

    Full Text Available The aim of this study is to investigate the intravascular application of a micro-electro-mechanical system (MEMS pressure sensor to directly measure the hemodynamic characteristics of a ventricular assist device (VAD. A bio- and hemo-compatible packaging strategy is implemented, based on a ceramic thick film process. A commercial sub-millimeter piezoresistive sensor is attached to an alumina substrate, and a double coating of polydimethylsiloxane (PDMS and parylene-C is applied. The final size of the packaged device is 2.6 mm by 3.6 mm by 1.8 mm. A prototype electronic circuit for conditioning and read-out of the pressure signal is developed, satisfying the VAD-specific requirements of low power consumption (less than 14.5 mW in continuous mode and small form factor. The packaged sensor has been submitted to extensive in vitro tests. The device displayed a temperature-independent sensitivity (12 μ V/V/mmHg and good in vitro stability when exposed to the continuous flow of saline solution (less than 0.05 mmHg/day drift after 50 h. During in vivo validation, the transducer has been successfully used to record the arterial pressure waveform of a female sheep. A small, intravascular sensor to continuously register the blood pressure at the inflow and the outflow of a VAD is developed and successfully validated in vivo.

  6. Towards Comparison of Ultrasound Dose Measurements - Current Capabilities and Open Challenges

    Science.gov (United States)

    Durando, G.; Guglielmone, C.; Haller, J.; Georg, O.; Shaw, A.; Martin, E.; Karaböce, B.

    The aim of this work is to evaluate measurement methods for dosimetry and exposimetry quantities that were developed in the EMRP project "Dosimetry for Ultrasound Therapy -DUTy" by comparing the measurement results for three common quantities from three national laboratories. It further aims to investigate the general feasibility of possible future (key) comparisons for dosimetry and exposimetry quantities and to identify possible open challenges towards this goal. The general format is similar to a metrological comparison, with which the National Metrological Institutes, NMIs, are already familiar. The first step involved the agreement of the protocol that was to specify the set of transducers to be circulated and the measurement conditions. Two transducers were circulated and different drive voltage levels and pulsing regimes were defined and tissue mimicking materials (TMMs) characteristics were specified. Each lab was asked to prepare the TMMs for their own measurements with the inclusion of formulations and preparation instructions specified in the protocol. Uncertainties of the input data were to be declared by the participating laboratories.

  7. Prostate Ultrasound

    Medline Plus

    Full Text Available ... through blood vessels. Ultrasound imaging is a noninvasive medical test that helps physicians diagnose and treat medical conditions. Prostate ultrasound, also called transrectal ultrasound, provides ...

  8. Common fetal measurements: A comparison between ultrasound and magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Parkar, Anagha P. (Dept. of Radiology, Haukeland Univ. Hospital, Bergen (Norway)); Olsen, Oeystein E.; Rosendahl, Karen (Diagnostic Radiology, Great Ormond Street Hospital for Children, London (United Kingdom)), e-mail: rosenk@gosh.nhs.uk; Gjelland, Knut; Kiserud, Torvid (Fetal Medicine Unit, Dept. of Obstetrics and Gynecology, Haukeland Univ. Hospital, Bergen (Norway))

    2010-01-15

    Background: Ultrasound has been the method of choice for antenatal fetal assessment for the past three decades; however, problems may arise in cases of oligohydramnion, unfavorable position of the fetus, and maternal obesity. Purpose: To compare ultrasound (US) and magnetic resonance imaging (MRI) for common fetal measurements at 19-30 weeks' gestation, and to assess the effect of high maternal body-mass index (BMI). Material and Methods: 59 low-risk singleton pregnancies were enrolled in a prospective blinded cross-sectional study. In a first session, an experienced obstetrician used a high-resolution US technique and in a second session on the same day MRI was used to measure biparietal diameter (BPD), head circumference (HC), mean abdominal diameter (MAD), abdominal circumference (AC), and femur length (FL). Inter- and intraobserver and intermodality variability was determined using Bland-Altman plots. The effect of maternal BMI was assessed using Spearman's statistics. Results: A total of 45 women aged 19-43 years (median 29 years) attended both US and MRI at median 22 weeks' gestation. The mean differences between US and MRI were 1.6 mm for HC (95% confidence interval [CI] -1.0, 4.3 mm), 1 mm for AC (95% CI -0.2, 4.0 mm), 0.2 mm for MAD (95% CI -0.7, 1.2 mm), 2.2 mm for BPD (95% CI 1.7, 2.7 mm), and 4.6 mm for FL (95% CI 2.9, 6.4 mm). Maternal BMI did not affect the results (Spearman' rho 0.054-0.277; P=NS). The intraobserver agreement for all MRI measurements was acceptable, except for FL, while the interobserver agreement was poor. Conclusion: There was good agreement between US and MRI for common fetal measurements, but not for all (i.e., BPD and particularly FL). MRI had a poor interobserver agreement, underscoring the need for technical refinement and reference ranges specifically established for MRI

  9. Reproducibility of Ultrasound and Magnetic Resonance Imaging Measurements of Tendon Size

    International Nuclear Information System (INIS)

    Brushoej, C.; Henriksen, B.M.; Albrecht-Beste, E.; Hoelmich, P.; Larsen, K.; Bachmann Nielsen, M.

    2006-01-01

    Purpose: To investigate the intra- and inter-tester reproducibility of measurements of the Achilles tendon, tibialis anterior tendon, and the tibialis posterior tendon in football players using ultrasound (US) and magnetic resonance imaging (MRI). Material and Methods: Eleven asymptomatic football players were examined. Using a standardized US scanning protocol, the tendons were examined by two observers with US for thickness, width, and cross-sectional area. One observer conducted the procedure twice. The subjects also underwent an MRI examination, and the assessment of tendon size was conducted twice by two observers. Results: The best reproducibility judged by coefficient of variation (CV) and 95% confidence interval was determined for the Achilles tendon on both US and MRI. The variability of US on measurements on the tibialis anterior and tibialis posterior tendons was less than that when using MRI. In 12 out of 18 measurements, there were systematic differences between observers as judged by one-sided F-test. Conclusion: The reproducibility of the three tendons was limited. Precaution should be taken when looking for minor quantitative changes, i.e., training-induced hypertrophy, and when doing so, the Achilles tendon should be used

  10. Transabdominal ultrasound measurement of rectal diameter is dependent on time to defecation in constipated children

    DEFF Research Database (Denmark)

    Modin, Line; Dalby, Kasper; Walsted, Anne-Mette

    2015-01-01

    AIM: To study whether diurnal variations and time in relation to defecation has to be taken into account when measurements of rectal diameter are used to determine faecal impaction in constipated children. METHODS: Repeated ultrasound measures of rectal diameter were performed in 28 children (14...... constipated/14 healthy, aged between 4 and 12 years) every third hour during 24 h. After defecation, three additional scans were performed at 1-h intervals. RESULTS: No diurnal variation in rectal diameter was found in the healthy group. In the constipated group, mean rectal diameter was significantly larger...... at 2 pm (P = 0.038) and 5 pm (P = 0.006). There were significant differences between rectal diameter in the healthy group and the constipated group at 2 pm (P = 0.016) and 5 pm (P = 0.027). When we omitted the rectal diameter of five constipated children who had their first bowel movement after 5 pm...

  11. Inverse problem in anisotropic poroelasticity: drained constants from undrained ultrasound measurements.

    Science.gov (United States)

    Berryman, James G; Nakagawa, Seiji

    2010-02-01

    Poroelastic analysis has traditionally focused on the relationship between dry and drained constants, which are assumed known, and the saturated or undrained constants, which are assumed unknown. However, there are many applications in this field of study for which the main measurements can only be made on the saturated/undrained system, and then it is uncertain what the effects of the fluids were on the system, since the drained constants remain a mystery. The work presented here shows how to deduce drained constants from undrained constants for anisotropic systems having symmetries ranging from isotropic to orthotropic. Laboratory ultrasound data are then inverted for the drained constants in three granular packings: one of glass beads, and two others for distinct types of more or less angular sand grain packings. Experiments were performed under uniaxial stress, which resulted in hexagonal (transversely isotropic) symmetry of the poroelastic response. One important conclusion from the general analysis is that the drained constants are uniquely related to the undrained constants, assuming that porosity, grain bulk modulus, and pore fluid bulk modulus are already known. Since the resulting system of equations for all the drained constants is linear, measurement error in undrained constants also propagates linearly into the computed drained constants.

  12. Inverse problem in anisotropic poroelasticity: Drained constants from undrained ultrasound measurements

    Energy Technology Data Exchange (ETDEWEB)

    Berryman, J.G.; Nakagawa, S.

    2009-11-20

    Poroelastic analysis has traditionally focused on the relationship between dry or drained constants which are assumed known and the saturated or undrained constants which are assumed unknown. However, there are many applications in this field of study for which the main measurements can only be made on the saturated/undrained system, and then it is uncertain what the eects of the uids were on the system, since the drained constants remain a mystery. The work presented here shows how to deduce drained constants from undrained constants for anisotropic systems having symmetries ranging from isotropic to orthotropic. Laboratory ultrasound data are then inverted for the drained constants in three granular packings: one of glass beads, and two others for distinct types of more or less angular sand grain packings. Experiments were performed under uniaxial stress, which resulted in hexagonal (transversely isotropic) symmetry of the poroelastic response. One important conclusion from the general analysis is that the drained constants are uniquely related to the undrained constants, assuming that porosity, grain bulk modulus, and pore uid bulk modulus are already known. Since the resulting system of equations for all the drained constants is linear, measurement error in undrained constants also propagates linearly into the computed drained constants.

  13. Characterization of fetal growth by repeated ultrasound measurements in the wild guinea pig (Cavia aperea).

    Science.gov (United States)

    Schumann, K; Guenther, A; Göritz, F; Jewgenow, K

    2014-08-01

    Fetal growth during pregnancy has previously been studied in the domesticated guinea pig (Cavia aperea f. porcellus) after dissecting pregnant females, but there are no studies describing the fetal growth in their wild progenitor, the wild guinea pig (C aperea). In this study, 50 pregnancies of wild guinea pig sows were investigated using modern ultrasound technique. The two most common fetal growth parameters (biparietal diameter [BPD] and crown-rump-length [CRL]) and uterine position were measured. Data revealed similar fetal growth patterns in the wild guinea pig and domesticated guinea pig in the investigated gestation period, although they differ in reproductive milestones such as gestation length (average duration of pregnancy 68 days), average birth weight, and litter mass. In this study, pregnancy lasted on average 60.2 days with a variance of less than a day (0.96 days). The measured fetal growth parameters are strongly correlated with each (R = 0.91; P guinea pig. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. The skin-to-calyx distance measured by renal ct scan and ultrasound

    Energy Technology Data Exchange (ETDEWEB)

    Shan, Chen Jen; Mazzucchi, Eduardo; Payão, Fabio; Gomes, Andrea Cavalanti; Baroni, Ronaldo Hueb; Torricelli, Fabio Cesar; Vicentini, Fabio Carvalho; Srougi, Miguel [Hospital das Clínicas, University of Sao Paulo Medical School, Sao Paulo, SP (Brazil)

    2014-03-15

    Purpose: We developed a stereotactic device to guide the puncture for percutaneous nephrolithotripsy, which uses the distance from the target calyx to its perpendicular point on skin (SCD) to calculate the needle´s entry angle. This study seeks to validate the use of measurements obtained by ultrasound (US) and computerized tomography (CT) for needle´s entry angle calculation and to study factors that may interfere in this procedure. Materials and Methods: Height, weight, abdominal circumference, CT of the urinary tract in dorsal decubitus (DD) and ventral decubitus (VD), and US of the kidneys in VD were obtained from thirty-five renal calculi patients. SCD obtained were compared and correlated with body-mass index (BMI). Results: BMI was 28.66 ± 4.6 Kg/m2. SCD on CT in DD was 8.40 ± 2.06cm, in VD was 8.32 ± 1.95cm, in US was 6.74 ± 1.68cm. SCD measured by US and CT were statistically different (p < 0.001), whereas between CT in DD and VD were not. SCD of the lower calyx presented moderate correlation with BMI. Conclusion: SCD obtained by CT in ventral and dorsal decubitus may be used for calculation of the needle´s entry angle. SCD obtained by US cannot be used. A rule for the correlation between BMI and the SCD could not be determined. (author)

  15. Quantitative head ultrasound measurements to determine thresholds for preterm neonates requiring interventional therapies following intraventricular hemorrhage

    Science.gov (United States)

    Kishimoto, Jessica; Fenster, Aaron; Salehi, Fateme; Romano, Walter; Lee, David S. C.; de Ribaupierre, Sandrine

    2016-04-01

    Dilation of the cerebral ventricles is a common condition in preterm neonates with intraventricular hemorrhage (IVH). This post hemorrhagic ventricle dilation (PHVD) can lead to lifelong neurological impairment through ischemic injury due to increased intracranial pressure and without treatment, can lead to death. Clinically, 2D ultrasound (US) through the fontanelles ('soft spots') of the patients are serially acquired to monitor the progression of the ventricle dilation. These images are used to determine when interventional therapies such as needle aspiration of the built up cerebrospinal fluid (CSF) ('ventricle tap', VT) might be indicated for a patient; however, quantitative measurements of the growth of the ventricles are often not performed. There is no consensus on when a neonate with PHVD should have an intervention and often interventions are performed after the potential for brain damage is quite high. Previously we have developed and validated a 3D US system to monitor the progression of ventricle volumes (VV) in IVH patients. We will describe the potential utility of quantitative 2D and 3D US to monitor and manage PHVD in neonates. Specifically, we will look to determine image-based measurement thresholds for patients who will require VT in comparison to patients with PHVD who resolve without intervention. Additionally, since many patients who have an initial VT will require subsequent interventions, we look at the potential for US to determine which PHVD patients will require additional VT after the initial one has been performed.

  16. Measurement and numerical simulation of high intensity focused ultrasound field in water

    Science.gov (United States)

    Lee, Kang Il

    2017-11-01

    In the present study, the acoustic field of a high intensity focused ultrasound (HIFU) transducer in water was measured by using a commercially available needle hydrophone intended for HIFU use. To validate the results of hydrophone measurements, numerical simulations of HIFU fields were performed by integrating the axisymmetric Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation from the frequency-domain perspective with the help of a MATLAB-based software package developed for HIFU simulation. Quantitative values for the focal waveforms, the peak pressures, and the size of the focal spot were obtained in various regimes of linear, quasilinear, and nonlinear propagation up to the source pressure levels when the shock front was formed in the waveform. The numerical results with the HIFU simulator solving the KZK equation were compared with the experimental data and found to be in good agreement. This confirms that the numerical simulation based on the KZK equation is capable of capturing the nonlinear pressure field of therapeutic HIFU transducers well enough to make it suitable for HIFU treatment planning.

  17. Preoperative ultrasound measurements predict the feasibility of gallbladder extraction during transgastric natural orifice translumenal endoscopic surgery cholecystectomy.

    Science.gov (United States)

    Santos, Byron F; Auyang, Edward D; Hungness, Eric S; Desai, Kush R; Chan, Edward S; van Beek, Darren B; Wang, Edward C; Soper, Nathaniel J

    2011-04-01

    Extraction of a gallbladder through an endoscopic overtube during natural orifice translumenal endoscopic surgery (NOTES) transgastric cholecystectomy avoids potential injury to the esophagus. This study examined the rate of successful gallbladder specimen extraction through an overtube and hypothesized that preoperative ultrasound findings could predict successful specimen passage. Gallbladder specimens from patients undergoing laparoscopic cholecystectomy were measured, and an attempt was made to pull the specimens through a commercially available overtube with an inner diameter of 16.7-mm. A radiologist blinded to the outcomes reviewed the available preoperative ultrasound measurements from these patients. Ultrasound dimensions including gallbladder length, width, and depth; wall thickness; common bile duct diameter; and size of the largest gallstone (LGS) were recorded. Multiple logistic regression analysis was performed to determine whether ultrasound findings and patient characteristics (age, body mass index [BMI], and sex) could predict the ability of a specimen to pass through the overtube. Of 57 patients, 44 (77%) who had preoperative ultrasounds available for electronic review were included in the final analysis. Gallstones were present in 35 (79%) of these 44 patients. Intraoperative gallbladder perforation occurred in 18 (41%) of the 44 patients, and 16 (36%) of the 44 gallbladders could be extracted through the overtube. Measurement of LGS was possible for 23 patients, and indeterminate gallstone size (IGS) was determined for 12 patients. The rate for passage of perforated versus intact gallbladders was similar (40% vs. 23%; p = 0.054). The LGS (odds ratio [OR], 1.17; 95% confidence interval [CI], 1.02-1.33; p = 0.021) and IGS (OR, 22.97; 95% CI, 1.99-265.63; p = 0.025) predicted failed passage on multivariate logistic regression analysis. The passage rate was 80% for LGS smaller than 10 mm or no stones present, 18% for LGS 10 mm or larger, and 8% for

  18. Theoretical model of intravascular paramagnetic tracers effect on tissue relaxation

    DEFF Research Database (Denmark)

    Kjølby, Birgitte Fuglsang; Østergaard, Leif; Kiselev, Valerij G

    2006-01-01

    The concentration of MRI tracers cannot be measured directly by MRI and is commonly evaluated indirectly using their relaxation effect. This study develops a comprehensive theoretical model to describe the transverse relaxation in perfused tissue caused by intravascular tracers. The model takes...... into account a number of individual compartments. The signal dephasing is simulated in a semianalytical way by embedding Monte Carlo simulations in the framework of analytical theory. This approach yields a tool for fast, realistic simulation of the change in the transverse relaxation. The results indicate...... with bulk blood. The enhancement of relaxation in tissue is due to the contrast in magnetic susceptibility between blood vessels and parenchyma induced by the presence of paramagnetic tracer. Beyond the perfusion measurements, the results can be applied to quantitation of functional MRI and to vessel size...

  19. Reproducibility of three-dimensional ultrasound for the measurement of a niche in a caesarean scar and assessment of its shape

    NARCIS (Netherlands)

    Bij de Vaate, A.J.M.; Linskens, I.H.; van der Voet, L.F.; Twisk, J.W.R.; Brölmann, H.A.M.; Huirne, J.A.F.

    2015-01-01

    Abstract Objective To evaluate the inter- and intraobserver agreement for measurement of the size and volume of a niche and assessment of the shape, with the use of three-dimensional (3D) ultrasound. Study design In this reproducibility study, 20 3D ultrasound volumes of uteri with a niche were

  20. Prostate Ultrasound

    Medline Plus

    Full Text Available ... ultrasound or with a rectal examination, an ultrasound-guided biopsy can be performed. This procedure involves advancing ... of the Prostate) Prostate Cancer Ultrasound- and MRI-Guided Prostate Biopsy Images related to Ultrasound - Prostate Sponsored ...

  1. Ultrasound -- Pelvis

    Medline Plus

    Full Text Available ... Ultrasound - Pelvis Ultrasound imaging of the pelvis uses sound waves to produce pictures of the structures and ... pictures of the inside of the body using sound waves. Ultrasound imaging, also called ultrasound scanning or ...

  2. Prostate Ultrasound

    Medline Plus

    Full Text Available ... Z Ultrasound - Prostate Ultrasound of the prostate uses sound waves to produce pictures of a man’s prostate ... pictures of the inside of the body using sound waves. Ultrasound imaging, also called ultrasound scanning or ...

  3. Ultrasound -- Pelvis

    Science.gov (United States)

    ... endometrial polyps fibroids cancer, especially in patients with abnormal uterine bleeding Some physicians also use 3-D ultrasound or ... Obstetric Ultrasound Ultrasound - Prostate Kidney and Bladder Stones Abnormal Vaginal Bleeding Ovarian Cancer Images related to Ultrasound - Pelvis Sponsored ...

  4. Relationship of femoral artery ultrasound measures of atherosclerosis with chronic kidney disease.

    Science.gov (United States)

    Hsu, Simon; Rifkin, Dena E; Criqui, Michael H; Suder, Natalie C; Garimella, Pranav; Ginsberg, Charles; Marasco, Antoinette M; McQuaide, Belinda J; Barinas-Mitchell, Emma J; Allison, Matthew A; Wassel, Christina L; Ix, Joachim H

    2017-12-22

    Chronic kidney disease (CKD) is strongly associated with peripheral artery disease (PAD). Detection of subclinical PAD may allow early interventions for or prevention of PAD in persons with CKD. Whether the presence of atherosclerotic plaque and femoral intima-media thickness (IMT) are associated with kidney function is unknown. We performed a cross-sectional observational study of 1029 community-living adults. We measured superficial and common femoral artery IMT and atherosclerotic plaque presence by ultrasound. Estimated glomerular filtration rate (eGFR; continuous) and eGFR <60 mL/min/1.73 m 2 (binary) were evaluated as outcomes. Mean age was 70 ± 10 years, mean eGFR was 78 ± 17 mL/min/1.73 m 2 , and 156 (15%) individuals had eGFR <60 mL/min/1.73 m 2 ; 260 (25%) had femoral artery plaque. In models adjusted for demographics and cardiovascular risk factors, individuals with femoral artery plaque had mean eGFR approximately 3.0 (95% confidence interval, -5.3 to -0.8) mL/min/1.73 m 2 lower than those without plaque (P < .01). The presence of plaque was also associated with a 1.7-fold higher odds of eGFR <60 mL/min/1.73 m 2 (95% confidence interval, 1.1-2.8; P < .02). Associations were similar in persons with normal ankle-brachial index. The directions of associations were similar for femoral IMT measures with eGFR and CKD but were rendered no longer statistically significant with adjustment for demographic variables and cardiovascular disease risk factors. Femoral artery plaque is significantly associated with CKD prevalence in community-living individuals, even among those with normal ankle-brachial index. Femoral artery ultrasound may allow evaluation of relationships and risk factors linking PAD and kidney disease earlier in its course. Copyright © 2017 Society for Vascular Surgery. All rights reserved.

  5. Hemi-Intravascular Stenting for Supermicrosurgical Anastomosis

    Science.gov (United States)

    Yamashita, Shuji; Narushima, Mitsunaga; Koshima, Isao; Miyamoto, Shimpei

    2017-01-01

    Background: Although supermicrosurgical anastomosis is a widely known reconstructive microsurgical technique, it is difficult to perform. To expand the clinical use of supermicrosurgery, we used hemi-intravascular stenting (hemi-IVaS), which is performed by inserting an intravascular stent into one side of the vessel. We conducted lymphaticovenular anastomosis, free perforator flap transfer, and fingertip replantation with supermicrosurgical anastomosis using hemi-IVaS technique and examined its usefulness. Methods: Between January 2013 and February 2015, 11 anastomoses in 11 cases of lymphaticovenular anastomosis for lymphedema patients, 14 anastomoses in 7 cases of free perforator flap transfer with supermicrosurgical perforator-to-perforator anastomosis, and 9 anastomoses in 5 cases of fingertip replantation were performed using hemi-IVaS. Time required for anastomosis and complications were examined. Flap survival rate was also examined in free perforator flap transfer cases and fingertip replantation cases. Results: In all cases, anastomoses were performed without complications such as inadvertent catching of the back wall of the vessel during the procedure or the need for reanastomoses. The average time required to complete the anastomosis was 16.4 ± 3.20 minutes using the hemi IVaS technique. All flaps survived in the supermicrosurgical perforator-to-perforator anastomosis as well as fingertip replantation cases. Conclusions: Hemi-IVaS could be a useful alternative to conventional intravascular stenting techniques and is also effective for supermicrosurgical perforator-to-perforator anastomosis. Further studies are needed to improve the success rate and to explore its other possible utilizations in supermicrosurgery. PMID:29263952

  6. Measurement of the ultrasound attenuation and dispersion in whole human blood and its components from 0-70 MHz.

    Science.gov (United States)

    Treeby, Bradley E; Zhang, Edward Z; Thomas, Alison S; Cox, Ben T

    2011-02-01

    The ultrasound attenuation coefficient and dispersion from 0-70 MHz in whole human blood and its components (red blood cells and plasma) at 37°C is reported. The measurements are made using a fixed path substitution technique that exploits optical mechanisms for the generation and detection of ultrasound. This allows the measurements to cover a broad frequency range with a single source and receiver. The measured attenuation coefficient and dispersion in solutions of red blood cells and physiological saline for total haemoglobin concentrations of 10, 15 and 20 g/dL are presented. The attenuation coefficient and dispersion in whole human blood taken from four healthy volunteers by venipuncture is also reported. The power law dependence of the attenuation coefficient is shown to vary across the measured frequency range. This is due to the varying frequency dependence of the different mechanisms responsible for the attenuation. The attenuation coefficient measured at high frequencies is found to be significantly higher than that predicted by historical power law parameters. A review of the attenuation mechanisms in blood along with previously reported experimental measurements is given. Values for the sound speed and density in the tested samples are also presented. Copyright © 2011 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  7. Intravascular imaging with a storage phosphor detector

    Energy Technology Data Exchange (ETDEWEB)

    Shikhaliev, Polad M; Petrek, Peter; Matthews, Kenneth L II; Fritz, Shannon G [Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA (United States); Bujenovic, L Steven [PET Imaging Center, Our Lady of the Lake Medical Center, Baton Rouge, LA (United States); Xu Tong, E-mail: pshikhal@lsu.ed [Department of Physics, Carleton University, Ottawa (Canada)

    2010-05-21

    The aim of this study is to develop and test an intravascular positron imaging system based on a storage phosphor detector for imaging and detecting vulnerable plaques of human coronary arteries. The radiotracer F18-FDG accumulates in vulnerable plaques with inflammation of the overlying cap. The vulnerable plaques can, therefore, be imaged by recording positrons emitted from F18-FDG with a detector inserted into the artery. A prototype intravascular detector was constructed based on storage phosphor. The detector uses a flexible storage phosphor tube with 55 mm length, 2 mm diameter and 0.28 mm wall thickness. The intravascular detector is guided into the vessel using x-ray fluoroscopy and the accumulated x-ray signal must be erased prior to positron imaging. For this purpose, a light diffuser, 0.9 mm in diameter and 55 mm in length, was inserted into the detector tube. The light diffuser was connected to a laser source through a 2 m long optical fiber. The diffuser redirected the 0.38 W laser light to the inner surface of the phosphor detector to erase it. A heart phantom with 300 cm{sup 3} volume and three coronary arteries with 3.2 mm diameter and with several plaques was constructed. FDG solution with 0.5 {mu}Ci cm{sup -3} activity concentration was filled in the heart and coronary arteries. The detector was inserted in a coronary artery and the signal from the plaques and surrounding background activity was recorded for 2 min. Then the phosphor detector was extracted and read out using a storage phosphor reader. The light diffuser erased the signal resulting from fluoroscopic exposure to level below that encountered during positron imaging. Vulnerable plaques with area activities higher than 1.2 nCi mm{sup -2} were visualized by the detector. This activity is a factor of 10-20 lower than that expected in human vulnerable plaques. The detector was able to image the internal surface of the coronary vessels with 50 mm length and 360{sup 0} circumference. Spatial

  8. Quantitative measurement of total cerebral blood flow using 2D phase-contrast MRI and doppler ultrasound

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Keum Soo; Choi, Sun Seob; Lee, Young Il [Dong-A Univ., College of Medicine, Busan (Korea, Republic of)

    2001-12-01

    To compare of quantitative measurement of the total cerebral blood flow using two-dimensional phase-contrast MR imaging and Doppler ultrasound. In 16 volunteers (mean age, 26 years; mean body weight, 66 kg) without abnormal medical histories, two-dimensional phase-contrast MR imaging was performed at the level of the C2-3 inter vertebral disc for flow measurement of the internal carotid arteries and the vertebral arteries. Volume flow measurements using Doppler ultrasound were also performed at the internal carotid arteries 2cm above the carotid bifurcation, and at the vertebral arteries at the level of the upper pole of the thyroid gland. Flows in the four vessels measured by the two methods were compared using Wilcoxon's correlation analysis and the median score. Total cerebral blood flows were calculated by summing these four vessel flows, and mean values for the 16 volunteers were calculated. Cerebral blood flows measured by 2-D phase-contrast MR imaging and Doppler ultrasounds were 233 and 239 ml/min in the right internal carotid artery, 250 and 248 ml/min in the left internal carotid artery, 62 and 56 ml/min in the right vertebral artery, and 83 and 68 ml/min in the left vertebral artery. Correlation coefficients of the blood flows determined by the two methods were 0.48, 0.54, 0.49, and 0.62 in each vessel, while total cerebral blood flows were 628{+-}68 (range, 517 to 779) ml/min and 612{+-}79 (range, 482 to 804)ml/min, respectively. Total cerebral blood flow was easily measured using 2-D phase-contrast MR imaging and Doppler ultrasound, and the two noninvasive methods can therefore be used clinically for the measurement of total cerebral blood flow.

  9. Comparison of grey scale median (GSM) measurement in ultrasound images of human carotid plaques using two different softwares.

    Science.gov (United States)

    Östling, Gerd; Persson, Margaretha; Hedblad, Bo; Gonçalves, Isabel

    2013-11-01

    Grey scale median (GSM) measured on ultrasound images of carotid plaques has been used for several years now in research to find the vulnerable plaque. Centres have used different software and also different methods for GSM measurement. This has resulted in a wide range of GSM values and cut-off values for the detection of the vulnerable plaque. The aim of this study was to compare the values obtained with two different softwares, using different standardization methods, for the measurement of GSM on ultrasound images of carotid human plaques. GSM was measured with Adobe Photoshop(®) and with Artery Measurement System (AMS) on duplex ultrasound images of 100 consecutive medium- to large-sized carotid plaques of the Beta-blocker Cholesterol-lowering Asymptomatic Plaque Study (BCAPS). The mean values of GSM were 35·2 ± 19·3 and 55·8 ± 22·5 for Adobe Photoshop(®) and AMS, respectively. Mean difference was 20·45 (95% CI: 19·17-21·73). Although the absolute values of GSM differed, the agreement between the two measurements was good, correlation coefficient 0·95. A chi-square test revealed a kappa value of 0·68 when studying quartiles of GSM. The intra-observer variability was 1·9% for AMS and 2·5% for Adobe Photoshop. The difference between softwares and standardization methods must be taken into consideration when comparing studies. To avoid these problems, researcher should come to a consensus regarding software and standardization method for GSM measurement on ultrasound images of plaque in the arteries. © 2013 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

  10. Confiabilidade da medida de espessuras musculares pela ultrassonografia Reliability of muscle thickness measurements using ultrasound

    Directory of Open Access Journals (Sweden)

    Paulo Sergio Chagas Gomes

    2010-02-01

    Full Text Available OBJETIVO: Determinar a confiabilidade das medidas de espessuras dos músculos flexores e extensores do cotovelo e joelho pela ultrassonografia (US, quantificando o erro típico associado a essas medidas (ETM. MÉTODOS: A confiabilidade (duas medidas interdias foi determinada em 15 voluntários aparentemente saudáveis (oito mulheres, 33,9 ± 11,4 anos, 76 ± 21kg, 170 ± 10cm. As imagens da musculatura flexora (FC e extensora do cotovelo (EC e flexora (FJ e extensora do joelho (EJ foram obtidas pela US bidimensional no modo B, utilizando transdutor de 7,5MHz. As espessuras do tecido muscular compreendidas entre as interfaces com o osso e com o tecido adiposo foram medidas em sítios anatômicos identificados e registrados para ser repetidos na segunda medida. RESULTADOS: A ANOVA não identificou diferenças significativas entre as medidas repetidas. Os coeficientes de correlação intraclasse foram FC = 0,970, EC = 0,971, FJ = 0,555 e EJ = 0,929 (P PURPOSE: To determine the reliability of muscle thickness measurements of elbow and knee flexors and extensors using ultrasound, and to quantify the typical error associated to the measurements (TEM. METHODS: The test-retest reliability was determined in 15 apparently healthy volunteers (8 women, 34 ± 11 years, 76 ± 21 kg, 170 ± 10 cm. The images of elbow flexors (EF and extensors (EE and knee flexors (KF and extensors (KE were obtained using a two dimensional mode B ultrasound instrument with a 7.5 MHz transducer. Muscle thickness between the adipose tissue and bone interfaces were measured at anatomical landmarks previously identified and recorded to assure the exact site for the retest. RESULTS: ANOVA did not identify any significant differences between the repeated measurements. Intraclass correlation coefficients (ICC of each pair of measure were EF = 0.970, EE = 0.971, KF = 0.555 e KE = 0.929 (P < 0.05 for all. The coefficients of variation were 3.9 %, 6.1 %, 6.6 % e 4.6 %, and TEM 1.3 mm, 1

  11. Application of focused ultrasounds to the measurement of the dimensions of defects in welds

    International Nuclear Information System (INIS)

    Foulquier, H.; Roule, M.; Saglio, R.; Touffait, A.M.

    1976-01-01

    Non destructive testing using ultrasounds must not only detect eventual defects but also give their nature and dimensions. C.E.A. has studied and developed focused transducers which permit the sizing of defects with high precision [fr

  12. Comparison of anterior chamber depths measured using the Pentacam, the IOLMaster, and ultrasound pachymetry

    Directory of Open Access Journals (Sweden)

    Jing Zhang

    2015-08-01

    Full Text Available AIM: To investigate and compare anterior chamber depths(ACDsmeasured using the Pentacam, the IOLMaster, and ultrasound pachymetry(US.METHODS: The present study was observational in nature. ACDs were measured in 138 eyes of 69 myopic patients, by the same operator, using the Pentacam, the IOLMaster, and US. We assessed the agreement among the three methods using Bland-Altman plots. The repeatability among the three methods was evaluated by within-subject standard deviation. RESULTS: The means±SDs of ACDs measured using the Pentacam, the IOLMaster, and US were 3.77±0.24, 3.73±0.23, and 3.69±0.22mm respectively. Bland-Altman analysis showed that Pentacam and IOLMaster data were in good agreement(CoA, 0.04mm; LoA,0.05 to 0.13mm, as were US and IOLMaster data(CoA, 0.04mm; LoA, 0.17 to 0.08mm, but the Pentacam ACD values were slightly greater than the US figures(CoA, 0.08mm; LoA, 0.06 to 0.22mm. Measurements of the ACD with the three devices also showed high repeatability(Sw=0.03, 0.02, and 0.03; 2.77 Sw=0.08, 0.06, and 0.08, respectively. The three depth estimates were positively correlated(r=0.946, 0.987, and 0.951; PCONCLUSION: Measurement of ACDs using the Pentacam, the IOLMaster, and US showed good agreement and repeatability. The Pentacam and IOLMaster ACDs, and the IOLMaster and US ACDs, agreed reasonably well, but agreement between the Pentacam and US data was poorer. However, both the absolute differences and the coefficients of variation were small, and the observed variability was likely not clinically significant.

  13. Exploratory Analysis of Carbon Dioxide Levels, Ultrasound and Optical Coherence Tomography Measures of the Eye During ISS Missions

    Science.gov (United States)

    Schaefer, C.; Coble, C.; Mason, S.; Young, M.; Wear, M. L.; Sargsyan, A.; Garcia, K.; Patel, N.; Gibson, C.; Alexander, D.; hide

    2017-01-01

    Carbon dioxide (CO2) levels on board the International Space Station (ISS) have typically averaged 2.3 to 5.3 mmHg, with large fluctuations occurring over periods of hours and days. CO2 has effects on cerebral vascular tone, resulting in vasodilation and alteration of cerebral blood flow (CBF). Increased CBF leads to elevated intracranial pressure (ICP), a factor leading to visual disturbances, headaches, and other central nervous system symptoms. Ultrasound of the optic nerve and optical coherence tomography (OCT) provide surrogate measurements of ICP; in-flight measurements of both were implemented as enhanced screening tools for the Visual Impairment/Intracranial Pressure (VIIP) syndrome. This analysis examines the relationships between ambient CO2 levels on ISS, ultrasound and OCT measures of the eye in an effort to understand how CO2 may possibly be associated with VIIP and to inform future analysis of in-flight VIIP data.

  14. In vivo ultrasound and biometric measurements predict the empty body chemical composition in Nellore cattle.

    Science.gov (United States)

    Castilhos, A M; Francisco, C L; Branco, R H; Bonilha, S F M; Mercadante, M E Z; Meirelles, P R L; Pariz, C M; Jorge, A M

    2018-05-04

    Evaluation of the body chemical composition of beef cattle can only be measured postmortem and those data cannot be used in real production scenarios to adjust nutritional plans. The objective of this study was to develop multiple linear regression equations from in vivo measurements, such as ultrasound parameters [backfat thickness (uBFT, mm), rump fat thickness (uRF, mm), and ribeye area (uLMA, cm2)], shrunk body weight (SBW, kg), age (AG, d), hip height (HH, m), as well as from postmortem measurements (composition of the 9th to 11th rib section) to predict the empty body and carcass chemical composition for Nellore cattle. Thirty-three young bulls were used (339 ± 36.15 kg and 448 ± 17.78 d for initial weight and age, respectively). Empty body chemical composition (protein, fat, water, and ash in kg) was obtained by combining noncarcass and carcass components. Data were analyzed using the PROC REG procedure of SAS software. Mallows' Cp values were close to the ideal value of number of independent variables in the prediction equations plus one. Equations to predict chemical components of both empty body and carcass using in vivo measurements presented higher R2 values than those determined by postmortem measurements. Chemical composition of the empty body using in vivo measurements was predicted with R2 > 0.73. Equations to predict chemical composition of the carcass from in vivo measurements showed R2 lower (R2Chemical compounds from components of the empty body of Nellore cattle can be calculated by the following equations: protein (kg) = 47.92 + 0.18 × SBW - 1.46 × uRF - 30.72 × HH (R2 = 0.94, RMSPE = 1.79); fat (kg) = 11.33 + 0.16 × SBW + 2.09 × uRF - 0.06 × AG (R2 = 0.74, RMSPE = 4.18); water (kg) = - 34.00 + 0.55 × SBW + 0.10 × AG - 2.34 × uRF (R2 = 0.96, RMSPE = 5.47). In conclusion, the coefficients of determination (for determining the chemical composition of the empty body) of the equations derived from in vivo measures were higher than those

  15. Ultrasound measurement of the size of the anterior tibial muscle group: the effect of exercise and leg dominance

    LENUS (Irish Health Repository)

    McCreesh, Karen

    2011-09-13

    Abstract Background Knowledge of normal muscle characteristics is crucial in planning rehabilitation programmes for injured athletes. There is a high incidence of ankle and anterior tibial symptoms in football players, however little is known about the effect of limb dominance on the anterior tibial muscle group (ATMG). The purpose of this study was to assess the effect of limb dominance and sports-specific activity on ATMG thickness in Gaelic footballers and non-football playing controls using ultrasound measurements, and to compare results from transverse and longitudinal scans. Methods Bilateral ultrasound scans were taken to assess the ATMG size in 10 Gaelic footballers and 10 sedentary controls (age range 18-25 yrs), using a previously published protocol. Both transverse and longitudinal images were taken. Muscle thickness measurements were carried out blind to group and side of dominance, using the Image-J programme. Results Muscle thickness on the dominant leg was significantly greater than the non-dominant leg in the footballers with a mean difference of 7.3%, while there was no significant dominance effect in the controls (p < 0.05). There was no significant difference between the measurements from transverse or longitudinal scans. Conclusions A significant dominance effect exists in ATMG size in this group of Gaelic footballers, likely attributable to the kicking action involved in the sport. This should be taken into account when rehabilitating footballers with anterior tibial pathology. Ultrasound is a reliable tool to measure ATMG thickness, and measurement may be taken in transverse or longitudinal section.

  16. Sonographic evaluation of intravascular volume status: Can internal jugular or femoral vein collapsibility be used in the absence of IVC visualization?

    Directory of Open Access Journals (Sweden)

    Alistair Kent

    2015-01-01

    Full Text Available Introduction: Inferior vena cava collapsibility index (IVC-CI has been shown to correlate with both clinical and invasive assessment of intravascular volume status, but has important limitations such as the requirement for advanced sonographic skills, the degree of difficulty in obtaining those skills, and often challenging visualization of the IVC in the postoperative patient. The current study aims to explore the potential for using femoral (FV or internal jugular (IJV vein collapsibility as alternative sonographic options in the absence of adequate IVC visualization. Methods: A prospective, observational study comparing IVC-CI and Fem- and/or IJV-CI was performed in two intensive care units (ICU between January 2012 and April 2014. Concurrent M-mode measurements of IVC-CI and FV- and/or IJV-CI were collected during each sonographic session. Measurements of IVC were obtained using standard technique. IJV-CI and FV-CI were measured using high-frequency, linear array ultrasound probe placed in the corresponding anatomic areas. Paired data were analyzed using coefficient of correlation/determination and Bland-Altman determination of measurement bias. Results: We performed paired ultrasound examination of IVC-IJV (n = 39 and IVC-FV (n = 22, in 40 patients (mean age 54.1; 40% women. Both FV-CI and IJV-CI scans took less time to complete than IVC-CI scans (both, P < 0.02. Correlations between IVC-CI/FV-CI (R 2 = 0.41 and IVC-CI/IJV-CI (R 2 = 0.38 were weak. There was a mean -3.5% measurement bias between IVC-CI and IJV-CI, with trend toward overestimation for IJV-CI with increasing collapsibility. In contrast, FV-CI underestimated collapsibility by approximately 3.8% across the measured collapsibility range. Conclusion: Despite small measurement biases, correlations between IVC-CI and FV-/IJV-CI are weak. These results indicate that IJ-CI and FV-CI should not be used as a primary intravascular volume assessment tool for clinical decision support in

  17. Comparison of Colour Duplex Ultrasound with Computed Tomography to Measure the Maximum Abdominal Aortic Aneurysmal Diameter

    Directory of Open Access Journals (Sweden)

    C. Gray

    2014-01-01

    Full Text Available Introduction. Maximum diameter of an abdominal aortic aneurysm (AAA is the main indication for surgery. This study compared colour duplex ultrasound (CDU and computed tomography (CT in assessing AAA diameter. Patients and Methods. Patients were included if they had both scans performed within 90 days. Pearson’s correlation coefficient, paired t-test, and limits of agreement (LOA were calculated for the whole group. Subgroup analysis of small (6.5 cm aneurysms was performed. A P value of <0.05 was considered statistically significant. Results. 389 patients were included, giving 130 pairs of tests for comparison. Excellent correlation was in the whole group (r = 0.95 and in the subgroups (r = 0.94; 0.69; 0.96, resp.. Small LOA between the two imaging modalities was found in all subgroups. Conclusion. Small aneurysms can be accurately measured using CDU. CDU is preferable for small AAAs, but cannot supplant CT for planning aortic intervention.

  18. Superficial ultrasound shear wave speed measurements in soft and hard elasticity phantoms: repeatability and reproducibility using two ultrasound systems.

    Science.gov (United States)

    Dillman, Jonathan R; Chen, Shigao; Davenport, Matthew S; Zhao, Heng; Urban, Matthew W; Song, Pengfei; Watcharotone, Kuanwong; Carson, Paul L

    2015-03-01

    There is a paucity of data available regarding the repeatability and reproducibility of superficial shear wave speed (SWS) measurements at imaging depths relevant to the pediatric population. To assess the repeatability and reproducibility of superficial shear wave speed measurements acquired from elasticity phantoms at varying imaging depths using three imaging methods, two US systems and multiple operators. Soft and hard elasticity phantoms manufactured by Computerized Imaging Reference Systems Inc. (Norfolk, VA) were utilized for our investigation. Institution No. 1 used an Acuson S3000 US system (Siemens Medical Solutions USA, Malvern, PA) and three shear wave imaging method/transducer combinations, while institution No. 2 used an Aixplorer US system (SuperSonic Imagine, Bothell, WA) and two different transducers. Ten stiffness measurements were acquired from each phantom at three depths (1.0 cm, 2.5 cm and 4.0 cm) by four operators at each institution. Student's t-test was used to compare SWS measurements between imaging techniques, while SWS measurement agreement was assessed with two-way random effects single-measure intra-class correlation coefficients (ICCs) and coefficients of variation. Mixed model regression analysis determined the effect of predictor variables on SWS measurements. For the soft phantom, the average of mean SWS measurements across the various imaging methods and depths was 0.84 ± 0.04 m/s (mean ± standard deviation) for the Acuson S3000 system and 0.90 ± 0.02 m/s for the Aixplorer system (P = 0.003). For the hard phantom, the average of mean SWS measurements across the various imaging methods and depths was 2.14 ± 0.08 m/s for the Acuson S3000 system and 2.07 ± 0.03 m/s Aixplorer system (P > 0.05). The coefficients of variation were low (0.5-6.8%), and interoperator agreement was near-perfect (ICCs ≥ 0.99). Shear wave imaging method and imaging depth significantly affected measured SWS (P

  19. Role of informed consent for intravascular contrast media

    International Nuclear Information System (INIS)

    Hopper, K.D.; Tyler, H.N. Jr.

    1988-01-01

    To evaluate the usefulness of different degrees of informed consent for intravascular contrast media, the authors divided 100 patients into four groups: (1) informed consent with no information on intravascular contrast media, (2) simple written informed consent that detailed common risks, (3) detailed written informed consent that detailed all known risks, and (4) MD informed consent, during which a radiologist discussed all known risks of intravascular contrast media. Physician counseling time for group 4 averaged 11.4 minutes. On a postprocedure test about the common complications and risk factors of intravascular contrast media, the average scores were: group 1, 38.4%; group 2, 68.2%; group 3, 63.2%; and group 4, 69.8%. There was no statistical difference between groups 2-4 on the postprocedure test. If informed consent is to be used prior to intravascular contrast media administration, a simple written consent detailing the common risks and risk factors appears to be the best method

  20. The relationship between experimental geometry, heat rate, and ultrasound wave speed measurement while observing phase changes in highly attenuative materials

    Science.gov (United States)

    Moore, David G.; Stair, Sarah L.; Jack, David A.

    2018-04-01

    Ultrasound techniques are capable of monitoring changes in the time-of-flight as a material is exposed to different thermal environments. The focus of the present study is to identify the phase of a material via ultrasound compression wave measurements in a through transmission experimental setup as the material is heated from a solid to a liquid and then allowed to re-solidify. The present work seeks to expand upon the authors' previous research, which proved this through transmission phase monitoring technique was possible, by considering different experimental geometries. The relationship between geometry, the measured speed of sound, and the temperature profile is presented. The use of different volumes helps in establishing a baseline understanding of which aspects of the experiment are geometry dependent and which are independent. The present study also investigates the relationship between the heating rate observed in the experiment and the measured speed of sound. The trends identified between the experimental geometry, heat rate and ultrasound wave speed measurement assist in providing a baseline understanding of the applicability of this technique to various industries, including the polymer industry and the oil industry.

  1. A hybrid FDTD-Rayleigh integral computational method for the simulation of the ultrasound measurement of proximal femur.

    Science.gov (United States)

    Cassereau, Didier; Nauleau, Pierre; Bendjoudi, Aniss; Minonzio, Jean-Gabriel; Laugier, Pascal; Bossy, Emmanuel; Grimal, Quentin

    2014-07-01

    The development of novel quantitative ultrasound (QUS) techniques to measure the hip is critically dependent on the possibility to simulate the ultrasound propagation. One specificity of hip QUS is that ultrasounds propagate through a large thickness of soft tissue, which can be modeled by a homogeneous fluid in a first approach. Finite difference time domain (FDTD) algorithms have been widely used to simulate QUS measurements but they are not adapted to simulate ultrasonic propagation over long distances in homogeneous media. In this paper, an hybrid numerical method is presented to simulate hip QUS measurements. A two-dimensional FDTD simulation in the vicinity of the bone is coupled to the semi-analytic calculation of the Rayleigh integral to compute the wave propagation between the probe and the bone. The method is used to simulate a setup dedicated to the measurement of circumferential guided waves in the cortical compartment of the femoral neck. The proposed approach is validated by comparison with a full FDTD simulation and with an experiment on a bone phantom. For a realistic QUS configuration, the computation time is estimated to be sixty times less with the hybrid method than with a full FDTD approach. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Serial measurements of serum human placental lactogen (hPL) and serial ultrasound examinations in the evaluation of fetal growth

    DEFF Research Database (Denmark)

    Sørensen, Steen; von Tabouillot, D; Schioler, V

    2000-01-01

    Serial serum hPL measurements and serial ultrasound fetometry were compared in the evaluation of fetal growth by relating these two parameters to size at birth and to clinical factors known to influence size at birth. The data were from a prospective study of 1000 consecutive pregnant women...... considered to be at risk for fetal growth retardation with retrospective analysis. Serum hPL was measured by radioimmunoassay and fetal weight estimated by ultrasound every 3 weeks during the last trimester. hPL values were expressed as multiples of the median (MoM) and linear regression analysis of the h......PL MoM values was carried out for each pregnancy to find the slope of the line (hPL-slope); at least 3 serum hPL values were required. The estimated fetal weight and weight-for-age at birth was expressed in Z-scores. The individual intrauterine growth velocity was calculated by regression analysis...

  3. A step towards measuring the fetal head circumference with the use of obstetric ultrasound in a low resource setting

    Science.gov (United States)

    van den Heuvel, Thomas L. A.; Petros, Hezkiel; Santini, Stefano; de Korte, Chris L.; van Ginneken, Bram

    2017-03-01

    Worldwide, 99% of all maternal deaths occur in low-resource countries. Ultrasound imaging can be used to detect maternal risk factors, but requires a well-trained sonographer to obtain the biometric parameters of the fetus. One of the most important biometric parameters is the fetal Head Circumference (HC). The HC can be used to estimate the Gestational Age (GA) and assess the growth of the fetus. In this paper we propose a method to estimate the fetal HC with the use of the Obstetric Sweep Protocol (OSP). With the OSP the abdomen of pregnant women is imaged with the use of sweeps. These sweeps can be taught to somebody without any prior knowledge of ultrasound within a day. Both the OSP and the standard two-dimensional ultrasound image for HC assessment were acquired by an experienced gynecologist from fifty pregnant women in St. Luke's Hospital in Wolisso, Ethiopia. The reference HC from the standard two-dimensional ultrasound image was compared to both the manually measured HC and the automatically measured HC from the OSP data. The median difference between the estimated GA from the manual measured HC using the OSP and the reference standard was -1.1 days (Median Absolute Deviation (MAD) 7.7 days). The median difference between the estimated GA from the automatically measured HC using the OSP and the reference standard was -6.2 days (MAD 8.6 days). Therefore, it can be concluded that it is possible to estimate the fetal GA with simple obstetric sweeps with a deviation of only one week.

  4. Performance and ultrasound measurements of beef cattle fed diets based on whole corn or oats grains

    Directory of Open Access Journals (Sweden)

    Hugo M Arelovich

    2013-09-01

    Full Text Available This study intended to contrast dietary effects of whole grain oats versus corn included in rations with moderate roughage content on animal performance, beef ultrasound measurements, rumen and blood parameters. Ten Aberdeen Angus steers (203 kg in individual pens were fed twice daily on either whole oats (OD or corn (CD based diets. Measurements were: DM intake (DMI, average daily gain (ADG, feed to gain ratio (F/G; back fat (BF and rib eye area (RA; blood parameters. Four cannulated steers were used to study rumen pH, NH3-N and grain degradability. Rations dietary components were 55% grain, 30.1% barley straw, and 10.6% whole soybeans. Despite calculated higher ME supply (P = 0.0887 no differences were found for DMI, ADG, or F/G. Metabolizable protein intake (19.4% was larger and degradable protein intake (43.3% smaller for CD compared with OD (P < 0.01. The growth rate (cm² d-1 for RA was 40% grater for OD, but larger BF deposition (P = 0.0787 was found for CD. Blood Mg was higher for OD (p = 0.0564, nevertheless other blood parameters remained unaffected. Rumen pH and NH3-N were not influenced by diet, variations were only observed within time periods. Rumen pH decreased linearly from 7.05 to 6.13 and 7.11 to 6.37 for OD and CD respectively (P < 0.05. Minimum NH3-N concentrations (mg dL-1 were reached 12 and 18 h after morning meal for OD (7.10 and CD (5.82 respectively. Rumen degradation was larger for oats than corn. Whole oats rather than corn fed up to 55% of total DM seems to improve protein deposition, without significant changes in animal performance, rumen environment or blood parameters.

  5. Molecular imaging with targeted contrast ultrasound.

    Science.gov (United States)

    Piedra, Mark; Allroggen, Achim; Lindner, Jonathan R

    2009-01-01

    Molecular imaging with contrast-enhanced ultrasound uses targeted microbubbles that are retained in diseased tissue. The resonant properties of these microbubbles produce acoustic signals in an ultrasound field. The microbubbles are targeted to diseased tissue by using certain chemical constituents in the microbubble shell or by attaching disease-specific ligands such as antibodies to the microbubble. In this review, we discuss the applications of this technique to pathological states in the cerebrovascular system including atherosclerosis, tumor angiogenesis, ischemia, intravascular thrombus, and inflammation. Copyright 2009 S. Karger AG, Basel.

  6. A high pulse repetition frequency ultrasound system for the ex vivo measurement of mechanical properties of crystalline lenses with laser-induced microbubbles interrogated by acoustic radiation force

    International Nuclear Information System (INIS)

    Yoon, Sangpil; Emelianov, Stanislav; Aglyamov, Salavat; Karpiouk, Andrei

    2012-01-01

    A high pulse repetition frequency ultrasound system for an ex vivo measurement of mechanical properties of an animal crystalline lens was developed and validated. We measured the bulk displacement of laser-induced microbubbles created at different positions within the lens using nanosecond laser pulses. An impulsive acoustic radiation force was applied to the microbubble, and spatio-temporal measurements of the microbubble displacement were assessed using a custom-made high pulse repetition frequency ultrasound system consisting of two 25 MHz focused ultrasound transducers. One of these transducers was used to emit a train of ultrasound pulses and another transducer was used to receive the ultrasound echoes reflected from the microbubble. The developed system was operating at 1 MHz pulse repetition frequency. Based on the measured motion of the microbubble, Young’s moduli of surrounding tissue were reconstructed and the values were compared with those measured using the indentation test. Measured values of Young’s moduli of four bovine lenses ranged from 2.6 ± 0.1 to 26 ± 1.4 kPa, and there was good agreement between the two methods. Therefore, our studies, utilizing the high pulse repetition frequency ultrasound system, suggest that the developed approach can be used to assess the mechanical properties of ex vivo crystalline lenses. Furthermore, the potential of the presented approach for in vivo measurements is discussed. (paper)

  7. Influence of power density on the setting behaviour of light-cured glass-ionomer cements monitored by ultrasound measurements.

    Science.gov (United States)

    Tonegawa, Motoka; Yasuda, Genta; Chikako, Takubo; Tamura, Yukie; Yoshida, Takeshi; Kurokawa, Hiroyasu; Miyazaki, Masashi

    2009-07-01

    To monitor the influence of the power density of the curing unit on the setting behaviour of light-cured glass-ionomer cements (LCGICs) using ultrasound measurements. The ultrasound equipment comprised a pulser-receiver, transducers and an oscilloscope. The LCGICs used were Fuji II LC, Fuji II LC EM and Fuji Filling LC. The cements were mixed according to the manufacturer's instructions and then inserted into a transparent mould. The specimens were placed on the sample stage and cured with power densities of 0 (no irradiation), 200 or 600 mW/cm(2). The transit time through the cement disk was divided by the specimen thickness and then the longitudinal ultrasound velocity (V) within the material was obtained. Analysis of variance and Tukey's Honestly Significantly Different test were used to compare the V values between the set cements. When the LCGICs were light-irradiated, each curve displayed an initial plateau at approximately 1500 m/s and then rapidly increased to a second plateau at approximately 2600 m/s. The rate of increase of V was retarded when the cements were light-irradiated with a power density of 200 mW/cm(2) than with a power density of 600 mW/cm(2). Although sonic echoes were detected from the beginning of the measurements, the rates of increase of the sonic velocity were relatively slow when the cement was not light-irradiated. The ultrasound device monitored the setting processes of LCGICs accurately based on the longitudinal V. The polymerization behaviour of LCGICs was shown to be affected by the power density of the curing unit.

  8. Experimental and clinical trial of measuring urinary velocity with the pitot tube and a transrectal ultrasound guided video urodynamic system.

    Science.gov (United States)

    Tsujimoto, Yukio; Nose, Yorihito; Ohba, Kenkichi

    2003-01-01

    The pitot tube is a common device to measure flow velocity. If the pitot tube is used as an urodynamic catheter, urinary velocity and urethral pressure may be measured simultaneously. However, to our knowledge, urodynamic studies with the pitot tube have not been reported. We experimentally and clinically evaluated the feasibility of the pitot tube to measure urinary velocity with a transrectal ultrasound guided video urodynamic system. We carried out a basal experiment measuring flow velocity in model urethras of 4.5-8.0 mm in inner diameter with a 12-Fr pitot tube. In a clinical trial, 79 patients underwent transrectal ultrasound guided video urodynamic studies with the 12-Fr pitot tube. Urinary velocity was calculated from dynamic pressure (Pd) with the pitot tube formula and the correcting equation according to the results of the basal experiment. Velocity measured by the pitot tube was proportional to the average velocity in model urethras and the coefficients were determined by diameters of model urethras. We obtained a formula to calculate urinary velocity from the basal experiment. The urinary velocity could be obtained in 32 of 79 patients. Qmax was 8.1 +/- 4.3 mL/s (mean +/- SD; range, 18.4-1.3 mL/s), urethral diameter was 7.3 +/- 3.0 mm (mean +/- SD; range, 18.7-4.3 mm) and urinary velocity was 69.4 +/- 43.6 (mean +/- SD; range, 181.3-0 cm/s) at maximum flow rate. The correlation coefficient of Qmax measured by a flowmeter versus Qdv flow rate calculated with urethral diameter and velocity was 0.41 without significant difference. The use of the pitot tube as an urodynamic catheter to a transrectal ultrasound-guided video urodynamic system can measure urethral pressure, diameter and urinary velocity simultaneously. However, a thinner pitot tube and further clinical trials are needed to obtain more accurate results.

  9. Ventricular metastasis resulting in disseminated intravascular coagulation

    Directory of Open Access Journals (Sweden)

    Davis Ian D

    2005-05-01

    Full Text Available Abstract Background Disseminated Intravascular Coagulation (DIC complicates up to 7% of malignancies, the commonest solid organ association being adenocarcinoma. Transitional Cell Carcinoma (TCC has rarely been associated with DIC. Case presentation A 74-year-old woman with TCC bladder and DIC was found to have a cardiac lesion suspicious for metastatic disease. The DIC improved with infusion of plasma and administration of Vitamin K, however the cardiac lesion was deemed inoperable and chemotherapy inappropriate; given the patients functional status. We postulate that direct activation of the coagulation cascade by the intraventricular metastasis probably triggered the coagulopathy in this patient. Conclusion Cardiac metastases should be considered in cancer patients with otherwise unexplained DIC. This may influence treatment choices.

  10. Death following intravascular administration of contrast media

    International Nuclear Information System (INIS)

    Shehadi, W.H.

    1985-01-01

    Adverse reactions to intravascularly administered contrast media preceding death and the autopsy findings in 44 patients are presented. There is a wide scatter of the age distribution of fatal reactions. The highest incidence is in the 50-70 year age group. Similar observations were obtained from the 405 deaths due to contrast media reported to the Food and Drug Administration of the United States. In the same age group the number of reactions is highest, likewise the autopsy findings. The predominant autopsy findings are pulmonary edema, congestion and hemorrhage; arteriosclerosis, both general and coronary. In the younger age group the autopsy findings are limited mostly to the respiratory tract. Fatal reactions to contrast media occur often without warning and most deaths occur within 15 min to 6 hours. Reactions to contrast media occur without relation to sex or age. (orig.)

  11. Prehospital Ultrasound

    Directory of Open Access Journals (Sweden)

    Jen-Tang Sun

    2014-06-01

    Full Text Available Ultrasound is a commonly used diagnostic tool in clinical conditions. With recent developments in technology, use of portable ultrasound devices has become feasible in prehospital settings. Many studies also proved the feasibility and accuracy of prehospital ultrasound. In this article, we focus on the use of prehospital ultrasound, with emphasis on trauma and chest ultrasound.

  12. Joint reconstruction of the initial pressure and speed of sound distributions from combined photoacoustic and ultrasound tomography measurements

    Science.gov (United States)

    Matthews, Thomas P.; Anastasio, Mark A.

    2017-12-01

    The initial pressure and speed of sound (SOS) distributions cannot both be stably recovered from photoacoustic computed tomography (PACT) measurements alone. Adjunct ultrasound computed tomography (USCT) measurements can be employed to estimate the SOS distribution. Under the conventional image reconstruction approach for combined PACT/USCT systems, the SOS is estimated from the USCT measurements alone and the initial pressure is estimated from the PACT measurements by use of the previously estimated SOS. This approach ignores the acoustic information in the PACT measurements and may require many USCT measurements to accurately reconstruct the SOS. In this work, a joint reconstruction method where the SOS and initial pressure distributions are simultaneously estimated from combined PACT/USCT measurements is proposed. This approach allows accurate estimation of both the initial pressure distribution and the SOS distribution while requiring few USCT measurements.

  13. Intravascular ultrasonic-photoacoustic (IVUP) endoscope with 2.2-mm diameter catheter for medical imaging.

    Science.gov (United States)

    Bui, Nhat Quang; Hlaing, Kyu Kyu; Nguyen, Van Phuc; Nguyen, Trung Hau; Oh, Yun-Ok; Fan, Xiao Feng; Lee, Yong Wook; Nam, Seung Yun; Kang, Hyun Wook; Oh, Junghwan

    2015-10-01

    Intravascular ultrasound (IVUS) imaging is extremely important for detection and characterization of high-risk atherosclerotic plaques as well as gastrointestinal diseases. Recently, intravascular photoacoustic (IVPA) imaging has been used to differentiate the composition of biological tissues with high optical contrast and ultrasonic resolution. The combination of these imaging techniques could provide morphological information and molecular screening to characterize abnormal tissues, which would help physicians to ensure vital therapeutic value and prognostic significance for patients before commencing therapy. In this study, integration of a high-frequency IVUS imaging catheter (45MHz, single-element, unfocused, 0.7mm in diameter) with a multi-mode optical fiber (0.6mm in core diameter, 0.22 NA), an integrated intravascular ultrasonic-photoacoustic (IVUP) imaging catheter, was developed to provide spatial and functional information on light distribution in a turbid sample. Simultaneously, IVUS imaging was co-registered to IVPA imaging to construct 3D volumetric sample images. In a phantom study, a polyvinyl alcohol (PVA) tissue-mimicking arterial vessel phantom with indocyanine green (ICG) and methylene blue (MB) inclusion was used to demonstrate the feasibility of mapping the biological dyes, which are used in cardiovascular and cancer diagnostics. For the ex vivo study, an excised sample of pig intestine with ICG was utilized to target the biomarkers present in the gastrointestinal tumors or the atherosclerotic plaques with the proposed hybrid technique. The results indicated that IVUP endoscope with the 2.2-mm diameter catheter could be a useful tool for medical imaging. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Hybrid Segmentation of Vessels and Automated Flow Measures in In-Vivo Ultrasound Imaging

    DEFF Research Database (Denmark)

    Moshavegh, Ramin; Martins, Bo; Hansen, Kristoffer Lindskov

    2016-01-01

    Vector Flow Imaging (VFI) has received an increasing attention in the scientific field of ultrasound, as it enables angle independent visualization of blood flow. VFI can be used in volume flow estimation, but a vessel segmentation is needed to make it fully automatic. A novel vessel segmentation...

  15. Role of Ultrasound Volume Measurements of Testes in Evaluation of Infertile Men with Azoospermia

    International Nuclear Information System (INIS)

    Moon, Min Hoan; Sung, Chang Kyu; Cho, Jeong Yeon; Kim, Seung Hyup; Seo, Ju Tae; Chun, Yi Keong

    2012-01-01

    The purpose of our study was to assess the usefulness of ultrasound determined testicular volume in the evaluation of the infertile men with azoospermia. A computerized search from October 2005 to June 2010 generated a list of 45 infertile men with azoospermia (mean age, 34 years: age range, 26-44 years) who underwent both scrotal ultrasound and testis biopsy. Ultrasound determined testicular volumes were compared between infertile men with obstructive azoospermia and those with non-obstructive azoospermia. Testicular volume for obstructive azoospermia ranged from 6.4 ml to 26.9 ml, with a median volume of 14.0 ml. This volume was significantly larger than that of those with non-obstructive azoospermia, which ranged from 1.0 ml to 12.8 ml, with a median volume of 6.1 ml (p < 0.001). The area under the ROC curve for distinguishing non-obstructive azoospermia from obstructive azoospermia using testicular volume was 0.91. A cutoff value of less than or equal to 11.4 ml could distinguish non-obstructive azoospermia from obstructive azoospermia, with a sensitivity of 94.1% (95% CI; 71.3-99.9%) and a specificity of 73.3% (95% CI; 54.1-87.7%). Ultrasound-determined testicular volume can be helpful in the differentiation of obstructive azoospermia from non-obstructive azoospermia

  16. Influence of coupling substances in the measurement of ultrasound velocity in stone materials

    Science.gov (United States)

    Giuzio, Beatrice; Alvarez de Buergo, Monica; Fort, Rafael; Masini, Nicola

    2015-04-01

    Ultrasonic (US) testing is widely applied in many fields (i.e. aviation, petrochemical, power engineering, construction and metallurgical industries). In the field of built cultural heritage and science conservation, US testing can provide the quality of the historic building materials (physic-mechanical properties), their heterogeneity/homogeinity and anisotropy, in terms of materials characterization, but also how deterioration processes can affect their quality (either after natural decay or simulation ageing tests in the laboratory). Moreover, US testing is a useful technique in evaluating the effectiveness of conservation and restoration techniques such as assessing the compatibility among original and restoration materials, identification of original quarries, and the success or not in the increase of a material cohesion when applying consolidating products. In order to obtain precise, real and reliable measurements, coupling substances between the material surface and the ultrasonic sensors are frequently used, to provide a proper contact between the transducer and the material, to assure the perfect transmission of the ultrasonic wave. Various coupling agents can be applied for this purpose. According to Wesolowski (2012), the choice of the coupling agent significantly affects the measurement of propagation velocity in material samples and, as a consequence, the US test results. In this paper, the effect of six coupling agents (medical gel used for ultrasonography, gel + parafilm, plasticine, honey, glicerine and a plastic material provided for ultrasound measurement by Panametrics) on ultrasonic measurements conducted on specific building materials is investigated on two different types of building stones (granite and dolostone from the area of Madrid, traditionally used in the construction of the built heritage, 4 stone specimens for each rock variety, 20 x 6 x 8 cm). Direct and indirect modes measuring were performed, the first one with the transducers

  17. Ultrasound -- Pelvis

    Medline Plus

    Full Text Available ... a pelvic ultrasound examination. Doppler ultrasound , also called color Doppler ultrasonography, is a special ultrasound technique that ... and processes the sounds and creates graphs or color pictures that represent the flow of blood through ...

  18. Ultrasound -- Pelvis

    Medline Plus

    Full Text Available ... Ultrasound imaging is a noninvasive medical test that helps physicians diagnose and treat medical conditions. There are ... Ultrasound page for more information . Ultrasound examinations can help diagnose symptoms experienced by women such as: pelvic ...

  19. Ultrasound -- Pelvis

    Medline Plus

    Full Text Available ... three types of pelvic ultrasound: abdominal, vaginal (for women), and rectal (for men). These exams are frequently ... pelvic ultrasound: abdominal ( transabdominal ) vaginal ( transvaginal / endovaginal ) for women rectal ( transrectal ) for men A Doppler ultrasound exam ...

  20. Ultrasound -- Pelvis

    Medline Plus

    Full Text Available ... ultrasound images are captured in real-time, they can show the structure and movement of the body's ... Obstetrical Ultrasound page for more information . Ultrasound examinations can help diagnose symptoms experienced by women such as: ...

  1. A thermal technique for local ultrasound intensity measurement: part 2. Application to exposimetry on a medical diagnostic device

    International Nuclear Information System (INIS)

    Wilkens, V

    2010-01-01

    Acoustic output measurements on medical ultrasound equipment are usually performed using radiation force balances to determine the output power and using hydrophones to determine pressure and intensity parameters. The local temporal-average ultrasound intensity can be measured alternatively by thermal sensors. The technique was described and prototype sensors were characterized in a preceding paper. Here, the application of such a thermal intensity sensor to the output beam characterization of a typical medical diagnostic device is described. Two transducers, a 7.5 MHz linear array and a 3.5 MHz convex array were investigated in different operating modes. For comparison, hydrophone measurements were also performed. If the spatial averaging effect is taken into account, good agreement is found between both measurement methods. The maximum deviations of the spatial-peak temporal-average intensities I SPTA obtained with the thermal sensor from the corresponding hydrophone-based results were below 12%. The simple thermal technique offers advantages for intensity measurements especially in the case of scanning and combined modes of the diagnostic device, where the synchronization between hydrophone measurements and the complex pulse emission pattern can be difficult

  2. Ultrasound -- Pelvis

    Medline Plus

    Full Text Available ... through blood vessels. Ultrasound imaging is a noninvasive medical test that helps physicians diagnose and treat medical conditions. There are three types of pelvic ultrasound: ...

  3. Disseminated intravascular and intracardiac thrombosis after cardiopulmonary bypass

    Directory of Open Access Journals (Sweden)

    Deepak K Tempe

    2017-01-01

    Full Text Available Massive intracardiac and intravascular thrombosis is a rare complication following cardiopulmonary bypass (CPB. Most of the cases of the disseminated thrombosis have been reported in patients undergoing complex cardiac surgeries and those receiving antifibrinolytic agents during CPB. We report the occurrence of disseminated intravascular and intracardiac thrombosis after CPB in a patient undergoing mitral valve replacement in which no antifibrinolytic agent was used. The possible pathophysiology and management of the patient is discussed.

  4. Ultrasound imaging with a micromotor; Micromotor ni yoru choonpa imaging

    Energy Technology Data Exchange (ETDEWEB)

    Oshiro, O.; Salimuzzaman, M.; Matani, A.; Chihara, K. [Nara Institute of Science and Technology, Nara (Japan); Asao, M. [Osaka National Hospital, Osaka (Japan)

    1998-03-01

    This paper describes a new ultrasound intravascular imaging system. In this system, an ultrasound probe consists of a micromotor, an ultrasound reflecting mirror attached with the micromotor and an ultrasound transducer. Ultrasound is scanned radially by a micromotor instead of a rotation transmitting wire and the rotation of the micromotor is performed and controlled by an external magnetic field. This ultrasound imaging system with a micromotor was applied to observe the inside of blood vessels through in vitro experiments. The preliminary results suggest that this system has the sufficient ability to define the blood vessel morphology and that the simple image processing enhances signal-to-noise ratio of the reconstructed image. 12 refs., 5 figs.

  5. Catheter design optimization for practical intravascular photoacoustic imaging (IVPA) of vulnerable plaques

    Science.gov (United States)

    Iskander-Rizk, Sophinese; Wu, Min; Springeling, Geert; Mastik, Frits; Beurskens, Robert H. S. H.; van der Steen, Antonius F. W.; van Soest, Gijs

    2018-02-01

    Intravascular photoacoustic/ultrasound imaging (IVPA/US) can image the structure and composition of atherosclerotic lesions identifying lipid-rich plaques ex vivo and in vivo. In the literature, multiple IVPA/US catheter designs were presented and validated both in ex-vivo models and preclinical in-vivo situations. Since the catheter is a critical component of the imaging system, we discuss here a catheter design oriented to imaging plaque in a realistic and translatable setting. We present a catheter optimized for light delivery, manageable flush parameters and robustness with reduced mechanical damage risks at the laser/catheter joint interface. We also show capability of imaging within sheath and in water medium.

  6. A tissue phantom for visualization and measurement of ultrasound-induced cavitation damage.

    Science.gov (United States)

    Maxwell, Adam D; Wang, Tzu-Yin; Yuan, Lingqian; Duryea, Alexander P; Xu, Zhen; Cain, Charles A

    2010-12-01

    Many ultrasound studies involve the use of tissue-mimicking materials to research phenomena in vitro and predict in vivo bioeffects. We have developed a tissue phantom to study cavitation-induced damage to tissue. The phantom consists of red blood cells suspended in an agarose hydrogel. The acoustic and mechanical properties of the gel phantom were found to be similar to soft tissue properties. The phantom's response to cavitation was evaluated using histotripsy. Histotripsy causes breakdown of tissue structures by the generation of controlled cavitation using short, focused, high-intensity ultrasound pulses. Histotripsy lesions were generated in the phantom and kidney tissue using a spherically focused 1-MHz transducer generating 15 cycle pulses, at a pulse repetition frequency of 100 Hz with a peak negative pressure of 14 MPa. Damage appeared clearly as increased optical transparency of the phantom due to rupture of individual red blood cells. The morphology of lesions generated in the phantom was very similar to that generated in kidney tissue at both macroscopic and cellular levels. Additionally, lesions in the phantom could be visualized as hypoechoic regions on a B-mode ultrasound image, similar to histotripsy lesions in tissue. High-speed imaging of the optically transparent phantom was used to show that damage coincides with the presence of cavitation. These results indicate that the phantom can accurately mimic the response of soft tissue to cavitation and provide a useful tool for studying damage induced by acoustic cavitation. Copyright © 2010 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  7. Children's (Pediatric) Abdominal Ultrasound Imaging

    Medline Plus

    Full Text Available ... size, shape and consistency (whether the object is solid or filled with fluid). In medicine, ultrasound is ... ultrasound, measures the direction and speed of blood cells as they move through vessels. The movement of ...

  8. Measurement of compartment elasticity using pressure related ultrasound: a method to identify patients with potential compartment syndrome.

    Science.gov (United States)

    Sellei, R M; Hingmann, S J; Kobbe, P; Weber, C; Grice, J E; Zimmerman, F; Jeromin, S; Gansslen, A; Hildebrand, F; Pape, H C

    2015-01-01

    PURPOSE OF THE STUDY Decision-making in treatment of an acute compartment syndrome is based on clinical assessment, supported by invasive monitoring. Thus, evolving compartment syndrome may require repeated pressure measurements. In suspected cases of potential compartment syndromes clinical assessment alone seems to be unreliable. The objective of this study was to investigate the feasibility of a non-invasive application estimating whole compartmental elasticity by ultrasound, which may improve accuracy of diagnostics. MATERIAL AND METHODS In an in-vitro model, using an artificial container simulating dimensions of the human anterior tibial compartment, intracompartmental pressures (p) were raised subsequently up to 80 mm Hg by infusion of saline solution. The compartmental depth (mm) in the cross-section view was measured before and after manual probe compression (100 mm Hg) upon the surface resulting in a linear compartmental displacement (Δd). This was repeated at rising compartmental pressures. The resulting displacements were related to the corresponding intra-compartmental pressures simulated in our model. A hypothesized relationship between pressures related compartmental displacement and the elasticity at elevated compartment pressures was investigated. RESULTS With rising compartmental pressures, a non-linear, reciprocal proportional relation between the displacement (mm) and the intra-compartmental pressure (mm Hg) occurred. The Pearson's coefficient showed a high correlation (r2 = -0.960). The intraobserver reliability value kappa resulted in a statistically high reliability (κ = 0.840). The inter-observer value indicated a fair reliability (κ = 0.640). CONCLUSIONS Our model reveals that a strong correlation between compartmental strain displacements assessed by ultrasound and the intra-compartmental pressure changes occurs. Further studies are required to prove whether this assessment is transferable to human muscle tissue. Determining the complete

  9. Prediction of postpercutaneous coronary intervention myocardial infarction: insights from intravascular imaging, coronary flow, and biomarker evaluation.

    Science.gov (United States)

    Hoole, Stephen P; Hernández-Sánchez, Jules; Brown, Adam J; Giblett, Joel P; Bennett, Martin R; West, Nick E J

    2018-05-01

    Percutaneous coronary intervention-induced myocardial infarction (PMI) has prognostic significance. Identifying patients at high risk for PMI is desirable as it may alter strategy and facilitate early preventative therapy. We therefore sought to establish whether preprocedural demographic, interventional (plaque characteristics and coronary microcirculatory function), and inflammatory, endothelial damage, and platelet-derived biomarker data could predict the risk of PMI. We performed target vessel pressure wire to assess fractional flow reserve, index of microcirculatory resistance (IMR) and coronary flow reserve, plaque characterization by virtual histology intravascular ultrasound, and assayed peripheral biomarkers before uncomplicated PCI in 88 patients. We then analyzed post-PCI cardiac troponin level to adjudicate PMI based on the third universal definition of myocardial infarction. Overall incidence of PMI was 27%. Women [10/15 (66%) vs. 14/73 (19%), PPMI. Preprocedural coronary flow reserve was lower in individuals with a subsequent PMI (1.8±1.2 vs. 2.1±1.3. P=0.03), and patients with higher pre-PCI IMR were more likely to sustain PMI [IMR>22: 10/23 (44%) vs. ≤22: 14/65 (22%), P=0.04], although neither was predictive after multivariate analysis. Plaque characterization by virtual histology intravascular ultrasound did not discriminate those at risk of PMI. However, peripheral venous interleukin (IL)-18 and IL-8 levels were independently negatively and positively associated with PMI, respectively. Women and those with low BMI, particularly when associated with high IL-8 and low IL-18 levels, appear to be at increased risk of PMI.

  10. Intravascular Large B-Cell Lymphoma

    Directory of Open Access Journals (Sweden)

    Maria S. Khan MD, FACP

    2014-03-01

    Full Text Available Case Presentation . A 69-year-old Hispanic male, with a past history of diabetes and coronary disease, was admitted for fever, diarrhea, and confusion of 4 weeks duration. Physical examination showed a disoriented patient with multiple ecchymoses, possible ascites, and bilateral scrotal swelling. Hemoglobin was 6.7, prothrombin time (PT 21.4 seconds with international normalized ratio 2.1, partial thromboplastin time (PTT 55.6 seconds, fibrin split 10 µg/L, and lactate dehydrogenase (LDH 1231 IU/L. Except for a positive DNA test for Epstein–Barr virus (EBV infection, extensive diagnostic workup for infections, malignancy, or a neurological cause was negative. Mixing studies revealed a nonspecific inhibitor of PT and PTT but Factor VIII levels were normal. The patient was empirically treated with antibiotics but developed hypotension and died on day 27 of admission. At autopsy, patient was found to have intravascular diffuse large B-cell lymphoma involving skin, testes, lung, and muscles. The malignant cells were positive for CD20, CD791, Mum-1, and Pax-5 and negative for CD3, CD5, CD10, CD30, and Bcl-6. The malignant cells were 100% positive for Ki-67. Discussion . Intravascular large cell B-cell lymphoma (IVLBCL is rare form of diffuse large B-cell lymphoma and tends to proliferate within small blood vessels, particularly capillaries and postcapillary venules. The cause of its affinity for vascular bed remains unknown. In many reports, IVLBCL was associated with HIV, HHV8, and EBV infections. The fact that our case showed evidence of EBV infection lends support to the association of this diagnosis to viral illness. The available literature on this subject is scant, and in many cases, the diagnosis was made only at autopsy. The typical presentation of this disorder is with B symptoms, progressive neurologic deficits, and skin findings. Bone marrow, spleen, and liver are involved in a minority of patients. Nearly all patients have elevated LDH

  11. Laser-ultrasound spectroscopy apparatus and method with detection of shear resonances for measuring anisotropy, thickness, and other properties

    Science.gov (United States)

    Levesque, Daniel; Moreau, Andre; Dubois, Marc; Monchalin, Jean-Pierre; Bussiere, Jean; Lord, Martin; Padioleau, Christian

    2000-01-01

    Apparatus and method for detecting shear resonances includes structure and steps for applying a radiation pulse from a pulsed source of radiation to an object to generate elastic waves therein, optically detecting the elastic waves generated in the object, and analyzing the elastic waves optically detected in the object. These shear resonances, alone or in combination with other information, may be used in the present invention to improve thickness measurement accuracy and to determine geometrical, microstructural, and physical properties of the object. At least one shear resonance in the object is detected with the elastic waves optically detected in the object. Preferably, laser-ultrasound spectroscopy is utilized to detect the shear resonances.

  12. Reliability of pelvic floor measurements on three- and four-dimensional ultrasound during and after first pregnancy: implications for training.

    Science.gov (United States)

    van Veelen, G A; Schweitzer, K J; van der Vaart, C H

    2013-11-01

    To evaluate the reliability of measurements of the levator hiatus and levator-urethra gap (LUG) using three/four-dimensional (3D/4D) transperineal ultrasound in women during their first pregnancy and 6 months postpartum, and to assess the learning process for these measurements. An inexperienced observer was taught to perform measurements of the levator hiatus and LUG by an experienced observer. After training, 3D/4D ultrasound volume datasets of 40 women in the first trimester were analyzed by these two observers. Another training session then took place and both observers repeated the analyses of the same volume datasets. Finally, analyses of 40 volume datasets of the women 6 months postpartum were performed by both observers. Intra- and interobserver reliability were determined by intraclass correlation coefficients (ICC) with 95% CIs. For levator hiatal measurements, in the women during their first pregnancy the interobserver reliability was substantial to almost perfect after both the first and second training session (ICC, 0.62-0.83 and 0.71-0.89, respectively, for anteroposterior diameter, transverse diameter and area at rest, on contraction and on Valsalva) and the intraobserver reliability was substantial to almost perfect for both observers. For these measurements performed once the women had delivered, interobserver reliability was moderate to almost perfect. For LUG measurements performed during pregnancy, interobserver reliability was slight to moderate after the first training session (ICC, 0.14-0.54), but improved after the second training session (ICC, 0.38-0.71), and intraobserver reliability was moderate to substantial for the experienced observer and slight to moderate for the inexperienced observer. For these measurements performed when the women had delivered, interobserver reliability was fair to moderate. The levator hiatus and LUG can be measured reliably using 3D/4D ultrasound in primigravid and primiparous women. The technique to measure

  13. Ultrasound changes in the relationship between the urethra and bladder neck caused by prolapse repair: feasibility and reliability of measurements.

    Science.gov (United States)

    Duckett, J; Lautmann, K

    2012-10-01

    The objective of this study was to assess whether intraoperative transperineal ultrasound can be used to assess changes in the relationship between the urethra and bladder caused by a prolapse repair operation. The reliability of the measurements was also assessed. A total of 25 women having an anterior colporrhaphy operation had pre- and post-repair imaging using a standard bladder volume. There was a statistically significant change (p ≤ 0.04) in the posterior urethrovesical angle (PUA) from 115° (SD 37) before surgery, to 135° (SD 30) after surgery. There was no significant change (p = 0.93) in the anterior urethrovesical angle before 73° (SD 14) after surgery 73° (SD 14). Interclass correlation coefficients showed good reproducibility for all measurements. Ultrasound can be used to measure changes in the relationship of the urethra and bladder produced by anterior colporrhaphy. Clinically, the effect of these changes is to reduce the angulation of the urethra in relation to the bladder.

  14. Comparison of shear wave velocity measurements assessed with two different ultrasound systems in an ex-vivo tendon strain phantom.

    Science.gov (United States)

    Rosskopf, Andrea B; Bachmann, Elias; Snedeker, Jess G; Pfirrmann, Christian W A; Buck, Florian M

    2016-11-01

    The purpose of this study is to compare the reliability of SW velocity measurements of two different ultrasound systems and their correlation with the tangent traction modulus in a non-static tendon strain model. A bovine tendon was fixed in a custom-made stretching device. Force was applied increasing from 0 up to 18 Newton. During each strain state the tangent traction modulus was determined by the stretcher device, and SW velocity (m/s) measurements using a Siemens S3000 and a Supersonic Aixplorer US machine were done for shear modulus (kPa) calculation. A strong significant positive correlation was found between SW velocity assessed by the two ultrasound systems and the tangent traction modulus (r = 0.827-0.954, p Aixplorer 0.25 ± 0.3 m/s (p = 0.034). Mean difference of SW velocity between the two US-systems was 0.37 ± 0.3 m/s (p = 0.012). In conclusion, SW velocities are highly dependent on mechanical forces in the tendon tissue, but for controlled mechanical loads appear to yield reproducible and comparable measurements using different US systems.

  15. AISI/DOE Advanced Process Control Program Vol. 4 of 6: ON-LINE, NON-DESTRUCTIVE MECHANICAL PROPERTY MEASUREMENT USING LASER-ULTRASOUND

    Energy Technology Data Exchange (ETDEWEB)

    Andre' Moreau; Martin Lord; Daniel Levesqure; Marc Dubois; Jean Bussiere; Jean-Pierre Monchalin; Christian Padioleau; Guy Lamouche; Teodor Veres; Martin Viens; Harold Hebert; Pierre Basseras; Cheng-Kuei Jen

    2001-03-31

    The goal of this project was to demonstrate the feasibility to measure the mechanical properties, such as yield strength, tensile strength, elongation, strain hardening exponent and plastic strain ratio parameters, of low carbon steel sheets on the production line using laser ultrasound. The ultrasound generated by the developed apparatus travels mostly back and forth in the thickness of the steel sheet. By measuring the time delay between two echoes, and the relative amplitude of these two echoes, one can measure ultrasound velocity and attenuation. These are governed by the microstructure: grain size, crystallographic texture, dislocations, etc. Thus, by recording the time behavior of the ultrasonic signal, one can extract microstructural information. These microstructural information together with the modified Hall-Petch equation allow measurement of the mechanical properties. Through laboratory investigations with a laboratory laser ultrasound system, followed by the installation of a prototype system at LTV Steel Company's No.1 Inspection Line in Cleveland, all target mechanical properties of ultra low carbon (ULC), low carbon (LC) and high strength low alloy (HSLA) steel sample lots were measured meeting or nearly meeting all the target accuracies. Thus, the project realized its goal to demonstrate that the mechanical properties of low carbon steel sheets can be measured on-line using laser ultrasound

  16. Disseminated intravascular coagulation in solid tumors

    International Nuclear Information System (INIS)

    Terzieff, V.; Alonso, I.; Vázquez, A.

    2004-01-01

    It is estimated that 20-25% of cases of disseminated intravascular coagulation (DIC) relate to an underlying neoplasia primarily hematologic. It is estimated that about 5% of patients with solid tumors have CID clinic, although the incidence of subclinical alterations is much higher. The CID is not limited to the activation of the coagulation cascade, which leads to bleeding micro thrombosis and consumption of coagulation factors. Solid tumors are frequently associated adenocarcinomas producers mucin (especially gastric), usually in the context of a disseminated disease. The mucin may act as a promoter of the cascade, but probably it is a multi-event. High levels of TNF to produced by the tumor mass and chemotherapy-induced cell lysis have Also linked. Although the bleeding is usually oriented diagnosis, the most frequent cause of death is thrombosis. There are no specific tests for diagnosis. Elevated levels of D-dimer and products oriented fibrinogen degradation diagnosis. No reduction fibrinogen and almost always, one thrombocytopenia consumption. Treatment is complex and there is no consensus on many points. To recover the lost factors for consumption, it is recommended to use fresh frozen plasma and / or washed red blood cells. the heparin anticoagulation low dose is indicated since the disease causal can not be controlled quickly, but should not be initiated if there thrombocytopenia 50.000.El under profuse bleeding can require the use of tranexamic acid or EACA. Acute DIC, the case of our patient, is rare and very serious

  17. Ultrasound -- Pelvis

    Medline Plus

    Full Text Available ... Radiation Therapy for Gynecologic Cancers Radiation Therapy for Prostate Cancer top of page This page was reviewed on ... Abdomen Children's (Pediatric) Ultrasound - Abdomen Obstetric Ultrasound Ultrasound - Prostate Kidney and Bladder Stones Abnormal Vaginal Bleeding ... Images related to Ultrasound - Pelvis Sponsored by Please ...

  18. Ultrasound -- Pelvis

    Medline Plus

    Full Text Available ... endometrial polyps fibroids cancer, especially in patients with abnormal uterine bleeding Some physicians also use 3-D ultrasound or ... Obstetric Ultrasound Ultrasound - Prostate Kidney and Bladder Stones Abnormal Vaginal Bleeding Ovarian Cancer Images related to Ultrasound - Pelvis Sponsored ...

  19. Automatic Ultrasound Scanning

    DEFF Research Database (Denmark)

    Moshavegh, Ramin

    on the user adjustments on the scanner interface to optimize the scan settings. This explains the huge interest in the subject of this PhD project entitled “AUTOMATIC ULTRASOUND SCANNING”. The key goals of the project have been to develop automated techniques to minimize the unnecessary settings...... on the scanners, and to improve the computer-aided diagnosis (CAD) in ultrasound by introducing new quantitative measures. Thus, four major issues concerning automation of the medical ultrasound are addressed in this PhD project. They touch upon gain adjustments in ultrasound, automatic synthetic aperture image...

  20. Evaluation of CT virtual intravascular endoscopy in fenestrated stent grafts: a preliminary study

    International Nuclear Information System (INIS)

    Sun, Z.; Allen, Y.; Fitzsimmons, B.; Hartely, D.; Lawrence-Brown, M.

    2007-01-01

    We aim in this study to investigate the potential value of CT virtual intravascular endoscopy in patients diagnosed with abdominal aortic aneurysms undergoing fenestrated stent grafts. Both pre-and post-fenestration (within 3 months of implantation) multislice CT data were collected in eight patients and used for generation of virtual endoscopy images in our preliminary study. Variable fenestrations were deployed in 25 aortic branches with scallop fenestration implanted in six aortic ostia, large fenestration in four aortic ostia and small fenestration in 15 renal ostia, respectively. Measurements of the aortic ostia diameters both pre- and post-fenestration were successfully performed with virtual intravascular endoscopy visualization, and endovascular stents as well as their relationship to the aortic ostia were clearly demonstrated. Our results showed that there was no significant change of diameter of the aortic ostia following fenestrated stem grafts. Endovascular stents were clearly visualized on virtual endoscopy images, and no apparent deformity or malrotation was observed in this small group. Our preliminary study provides new insights into anatomic configuration/dimension of aortic ostia and endovascular stents, and virtual intravascular endoscopy could be a valuable technique to follow-up patients treated with fenestrated stent grafts. (orig.)

  1. Evaluation of CT virtual intravascular endoscopy in fenestrated stent grafts: a preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Z. [Dept. of Imaging and Applied Physics, Curtin Univ. of Tech., Perth, WA (Australia); Allen, Y.; Fitzsimmons, B.; Hartely, D. [Cook R and D, WA (Australia); Lawrence-Brown, M. [Dept. of Public Health, Curtin Univ. of Tech., Perth, WA (Australia)

    2007-06-15

    We aim in this study to investigate the potential value of CT virtual intravascular endoscopy in patients diagnosed with abdominal aortic aneurysms undergoing fenestrated stent grafts. Both pre-and post-fenestration (within 3 months of implantation) multislice CT data were collected in eight patients and used for generation of virtual endoscopy images in our preliminary study. Variable fenestrations were deployed in 25 aortic branches with scallop fenestration implanted in six aortic ostia, large fenestration in four aortic ostia and small fenestration in 15 renal ostia, respectively. Measurements of the aortic ostia diameters both pre- and post-fenestration were successfully performed with virtual intravascular endoscopy visualization, and endovascular stents as well as their relationship to the aortic ostia were clearly demonstrated. Our results showed that there was no significant change of diameter of the aortic ostia following fenestrated stem grafts. Endovascular stents were clearly visualized on virtual endoscopy images, and no apparent deformity or malrotation was observed in this small group. Our preliminary study provides new insights into anatomic configuration/dimension of aortic ostia and endovascular stents, and virtual intravascular endoscopy could be a valuable technique to follow-up patients treated with fenestrated stent grafts. (orig.)

  2. An experimental method for detecting blood splatter from retractable phlebotomy and intravascular devices.

    Science.gov (United States)

    Haiduven, Donna; Applegarth, Shawn; Shroff, Miloni

    2009-03-01

    This study was designed to evaluate the safety of retractable intravascular devices in terms of their potential to produce blood splatter. A method for measuring this blood splatter designed by the research team was used to evaluate 3 specific intravascular devices. Scientific filters were positioned around the retraction mechanisms of the devices and weighed with an analytical scale, both before and after activation, in a simulated vein containing mock venous blood. The difference in filter mass was used as the primary unit of analysis to detect blood splatter. In addition, the filters were visually inspected for the presence or absence of blood. A paired t-test revealed significant differences in the prefilter and postfilter groups for 2 of the 3 devices tested (P blood was detected on 23% to 40% of the scientific filters for 2 of the devices. Our findings indicate a potential for bloodborne pathogen exposure with the use of intravascular devices with a retractable mechanism. This experiment may serve as a model in the design and implementation of future sharps device evaluation protocols to validate the threat of bloodborne pathogen exposure.

  3. Ultrasound elastography as an objective diagnostic measurement tool for lymphoedema of the treated breast in breast cancer patients following breast conserving surgery and radiotherapy

    International Nuclear Information System (INIS)

    Adriaenssens, Nele; Belsack, Dries; Buyl, Ronald; Ruggiero, Leonardo; Breucq, Catherine; De Mey, Johan; Lievens, Pierre; Lamote, Jan

    2012-01-01

    Lymphoedema of the operated and irradiated breast is a common complication following early breast cancer treatment. There is no consensus on objective diagnostic criteria and standard measurement tools. This study investigates the use of ultrasound elastography as an objective quantitative measurement tool for the diagnosis of parenchymal breast oedema. The elasticity ratio of the subcutis, measured with ultrasound elastography, was compared with high-frequency ultrasound parameters and subjective symptoms in twenty patients, bilaterally, prior to and following breast conserving surgery and breast irradiation. Elasticity ratio of the subcutis of the operated breast following radiation therapy increased in 88.9% of patients, was significantly higher than prior to surgery, unlike the non operated breast and significantly higher than the non operated breast, unlike preoperative results. These results were significantly correlated with visibility of the echogenic line, measured with high-frequency ultrasound. Big preoperative bra cup size was a significant risk factor for the development of breast oedema. Ultrasound elastography is an objective quantitative measurement tool for the diagnosis of parenchymal breast oedema, in combination with other objective diagnostic criteria. Further research with longer follow-up and more patients is necessary to confirm our findings

  4. Reproducibility and interoperator reliability of obtaining images and measurements of the cervix and uterus with brachytherapy treatment applicators in situ using transabdominal ultrasound.

    Science.gov (United States)

    van Dyk, Sylvia; Garth, Margaret; Oates, Amanda; Kondalsamy-Chennakesavan, Srinivas; Schneider, Michal; Bernshaw, David; Narayan, Kailash

    2016-01-01

    To validate interoperator reliability of brachytherapy radiation therapists (RTs) in obtaining an ultrasound image and measuring the cervix and uterine dimensions using transabdominal ultrasound. Patients who underwent MRI with applicators in situ after the first insertion were included in the study. Imaging was performed by three RTs (RT1, RT2, and RT3) with varying degrees of ultrasound experience. All RTs were required to obtain a longitudinal planning image depicting the applicator in the uterine canal and measure the cervix and uterus. The MRI scan, taken 1 hour after the ultrasound, was used as the reference standard against which all measurements were compared. Measurements were analyzed with intraclass correlation coefficient and Bland-Altman plots. All RTs were able to obtain a suitable longitudinal image for each patient in the study. Mean differences (SD) between MRI and ultrasound measurements obtained by RTs ranged from 3.5 (3.6) to 4.4 (4.23) mm and 0 (3.0) to 0.9 (2.5) mm on the anterior and posterior surface of the cervix, respectively. Intraclass correlation coefficient for absolute agreement between MRI and RTs was >0.9 for all posterior measurement points in the cervix and ranged from 0.41 to 0.92 on the anterior surface. Measurements were not statistically different between RTs at any measurement point. RTs with variable training attained high levels of interoperator reliability when using transabdominal ultrasound to obtain images and measurements of the uterus and cervix with brachytherapy applicators in situ. Access to training and use of a well-defined protocol assist in achieving these high levels of reliability. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  5. Ultrasound guided pO2 measurement of breast cancer reoxygenation after neoadjuvant chemotherapy and hyperthermia treatment.

    Science.gov (United States)

    Vujaskovic, Z; Rosen, E L; Blackwell, K L; Jones, E L; Brizel, D M; Prosnitz, L R; Samulski, T V; Dewhirst, M W

    2003-01-01

    The objective of this study was to determine whether neoadjuvant chemotherapy in combination with hyperthermia (HT) would improve oxygenation in locally advanced breast tumours. The study describes a new optimized ultrasound guided technique of pO2 measurement using Eppendorf polarographic oxygen probes in 18 stage IIB-III breast cancer patients. Prior to treatment, tumour hypoxia (median pO2pO2=3.2 mmHg). Seven patients had well oxygenated tumours (median pO2 of 48.3 mmHg). Eight patients with hypoxic tumours prior to treatment had a significant improvement (p=0.0008) in tumour pO2 after treatment (pO2 increased to 19.2 mmHg). In three patients, tumours remained hypoxic (average median pO2=4.5 mmHg). The advantages of the ultrasound guided pO2 probe are in the accuracy of the Eppendorf electrode placement in tumour tissue, the ability to monitor electrode movement through the tumour tissue during the measurement and the ability to avoid electrode placement near or in large blood vessels by using colour Doppler imaging. The results of this preliminary study suggest that the combination of neoadjuvant chemotherapy and hyperthermia improves oxygenation in locally advanced breast tumours that are initially hypoxic.

  6. Measuring body layer vibration of vocal folds by high-frame-rate ultrasound synchronized with a modified electroglottograph.

    Science.gov (United States)

    Tang, Shanshan; Zhang, Yuanyuan; Qin, Xulei; Wang, Supin; Wan, Mingxi

    2013-07-01

    The body-cover concept suggests that the vibration of body layer is an indispensable component of vocal fold vibration. To quantify this vibration, a synchronized system composed of a high-frame-rate ultrasound and a modified electroglottograph (EGG) was employed in this paper to simultaneously image the body layer vibration and record the vocal fold vibration phase information during natural phonations. After data acquisition, the displacements of in vivo body layer vibrations were measured from the ultrasonic radio frequency data, and the temporal reconstruction method was used to enhance the measurement accuracy. Results showed that the modified EGG, the waveform and characteristic points of which were identical to the conventional EGG, resolved the position conflict between the ultrasound transducer and EGG electrodes. The location and range of the vibrating body layer in the estimated displacement image were more clear and discernible than in the ultrasonic B-mode image. Quantitative analysis for vibration features of the body layer demonstrated that the body layer moved as a unit in the superior-inferior direction during the phonation of normal chest registers.

  7. Ultrasound-assisted extraction for total sulphur measurement in mine tailings.

    Science.gov (United States)

    Khan, Adnan Hossain; Shang, Julie Q; Alam, Raquibul

    2012-10-15

    A sample preparation method for percentage recovery of total sulphur (%S) in reactive mine tailings based on ultrasound-assisted digestion (USAD) and inductively coupled plasma-optical emission spectroscopy (ICP-OES) was developed. The influence of various methodological factors was screened by employing a two-level and three-factor (2(3)) full factorial design and using KZK-1, a sericite schist certified reference material (CRM), to find the optimal combination of studied factors and %S. Factors such as the sonication time, temperature and acid combination were studied, with the best result identified as 20 min of sonication, 80°C temperature and 1 ml of HNO(3):1 ml of HCl, which can achieve 100% recovery for the selected CRM. Subsequently a fraction of the 2(3) full factorial design was applied to mine tailings. The percentage relative standard deviation (%RSD) for the ultrasound method is less than 3.0% for CRM and less than 6% for the mine tailings. The investigated method was verified by X-ray diffraction analysis. The USAD method compared favorably with existing methods such as hot plate assisted digestion method, X-ray fluorescence and LECO™-CNS method. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. Intravascular brachytherapy for peripheral vascular disease

    Directory of Open Access Journals (Sweden)

    Hagen, Anja

    2008-09-01

    Full Text Available Scientific background: Percutaneous transluminal angioplasties (PTA through balloon dilatation with or without stenting, i.e. vessel expansion through balloons with or without of implantation of small tubes, called stents, are used in the treatment of peripheral artery occlusive disease (PAOD. The intravascular vessel irradiation, called intravascular brachytherapy, promises a reduction in the rate of repeated stenosis (rate of restenosis after PTA. Research questions: The evaluation addresses questions on medical efficacy, cost-effectiveness as well as ethic, social and legal implications in the use of brachytherapy in PAOD patients. Methods: A systematic literature search was conducted in August 2007 in the most important medical electronic databases for publications beginning from 2002. The medical evaluation included randomized controlled trials (RCT. The information synthesis was performed using meta-analysis. Health economic modeling was performed with clinical assumptions derived from the meta-analysis and economical assumptions derived from the German Diagnosis Related Groups (G-DRG-2007. Results: Medical evaluation: Twelve publications about seven RCT on brachytherapy vs. no brachytherapy were included in the medical evaluation. Two RCT showed a significant reduction in the rate of restenosis at six and/or twelve months for brachytherapy vs. no brachytherapy after successful balloon dilatation, the relative risk in the meta-analysis was 0.62 (95% CI: 0.46 to 0.84. At five years, time to recurrence of restenosis was significantly delayed after brachytherapy. One RCT showed a significant reduction in the rate of restenosis at six months for brachytherapy vs. no brachytherapy after PTA with optional stenting, the relative risk in the meta-analysis was 0.76 (95% CI: 0.61 to 0.95. One RCT observed a significantly higher rate of late thrombotic occlusions after brachytherapy in the subgroup of stented patients. A single RCT for brachytherapy

  9. Fulminant intravascular lymphomatosis mimicking acute haemorrhagic leukoencephalopathy.

    Science.gov (United States)

    Marino, D; Sicurelli, F; Cerase, A; Tripodi, S; Cintorino, M; Lazzi, S; Federico, A

    2012-09-15

    Intravascular lymphomatosis (IVL) is a rare non-Hodgkin's lymphoma, usually of B cell lineage, characterized by massive angiotropic growth. The clinical presentation of IVL may include changes in mental status, non-localizing neurological deficits, seizures, fever of unknown origin and skin changes. Because of its rarity and the absence of specific diagnostic procedures except for cerebral biopsy, diagnosis is often postmortem. Brain MRI usually shows non-specific abnormalities. The purpose of this case report is to increase the knowledge of clinical and neuroimaging features of IVL by describing the findings observed in a 71-year-old patient. A 71-year-old male was admitted for right hemiparesis, acute cognitive impairment and febricula. A bone marrow biopsy resulted normal. He then developed a rapid progressive impairment of his mental status and left hemisoma motor seizures. Brain CT and MRI were interpreted as consistent with acute haemorrhagic leukoencephalopathy (AHLE), including multiple areas of restricted diffusion without gadolinium enhancement and a small focal area of gadolinium enhancement in the left temporal lobe white matter. The patient died within a few days and the autopsy led to the diagnosis of IVL. IVL may present with a variety of clinical signs and symptoms, including stroke and hemiparesis. IVL may mimic AHLE at brain MRI. However, the evidence of multiple areas of restricted diffusion without gadolinium enhancement and of a small area of gadolinium enhancement could have led to the correct diagnosis. IVL should be added to the differential diagnosis of AHLE at brain MRI. Copyright © 2012 Elsevier B.V. All rights reserved.

  10. Comparison of high-resolution Scheimpflug and high-frequency ultrasound biomicroscopy to anterior-segment OCT corneal thickness measurements

    Directory of Open Access Journals (Sweden)

    Kanellopoulos AJ

    2013-11-01

    Full Text Available Anastasios John Kanellopoulos,1,2 George Asimellis1 1Laservision.gr Eye Institute, Athens, Greece; 2New York University Medical School, New York, NY, USA Background: The purpose of this study was to compare and correlate central corneal thickness in healthy, nonoperated eyes with three advanced anterior-segment imaging systems: a high-resolution Scheimpflug tomography camera (Oculyzer II, a spectral-domain anterior-segment optical coherence tomography (AS-OCT system, and a high-frequency ultrasound biomicroscopy (HF-UBM system. Methods: Fifty eyes randomly selected from 50 patients were included in the study. Inclusion criteria were healthy, nonoperated eyes examined consecutively by the same examiner. Corneal imaging was performed by three different methods, ie, Oculyzer II, spectral-domain AS-OCT, and FH-UBM. Central corneal thickness measurements were compared using scatter diagrams, Bland-Altman plots (with bias and 95% confidence intervals, and two-paired analysis. Results: The coefficient of determination (r2 between the Oculyzer II and AS-OCT measurements was 0.895. Likewise, the coefficient was 0.893 between the Oculyzer II and HF-UBM and 0.830 between the AS-OCT and HF-UBM. The trend line coefficients of linearity were 0.925 between the Oculyzer II and the AS-OCT, 1.006 between the Oculyzer II and HF-UBM, and 0.841 between the AS-OCT and HF-UBM. The differences in average corneal thickness between the three pairs of CCT measurements were –6.86 µm between the Oculyzer II and HF-UBM, –12.20 µm between the AS-OCT and Oculyzer II, and +19.06 µm between the HF-UBM and AS-OCT. Conclusion: The three methods used for corneal thickness measurement are highly correlated. Compared with the Scheimplug and ultrasound devices, the AS-OCT appears to report a more accurate, but overally thinner corneal pachymetry. Keywords: anterior eye segment, high-frequency ultrasound biomicroscopy, optical coherence tomography, high-resolution Pentacam

  11. An ultrasound-based liquid pressure measurement method in small diameter pipelines considering the installation and temperature.

    Science.gov (United States)

    Li, Xue; Song, Zhengxiang

    2015-04-09

    Liquid pressure is a key parameter for detecting and judging faults in hydraulic mechanisms, but traditional measurement methods have many deficiencies. An effective non-intrusive method using an ultrasound-based technique to measure liquid pressure in small diameter (less than 15 mm) pipelines is presented in this paper. The proposed method is based on the principle that the transmission speed of an ultrasonic wave in a Kneser liquid correlates with liquid pressure. Liquid pressure was calculated using the variation of ultrasonic propagation time in a liquid under different pressures: 0 Pa and X Pa. In this research the time difference was obtained by an electrical processing approach and was accurately measured to the nanosecond level through a high-resolution time measurement module. Because installation differences and liquid temperatures could influence the measurement accuracy, a special type of circuit called automatic gain control (AGC) circuit and a new back propagation network (BPN) model accounting for liquid temperature were employed to improve the measurement results. The corresponding pressure values were finally obtained by utilizing the relationship between time difference, transient temperature and liquid pressure. An experimental pressure measurement platform was built and the experimental results confirm that the proposed method has good measurement accuracy.

  12. Therapeutic intervention in disseminated intravascular coagulation: have we made any progress in the last millennium?

    NARCIS (Netherlands)

    Levi, Marcel; de Jonge, Evert; van der Poll, Tom

    2002-01-01

    Disseminated intravascular coagulation (DIC) is a syndrome characterized by systemic intravascular activation of coagulation, leading to widespread deposition of fibrin in the circulation. Recent knowledge on important pathogenetic mechanisms that may lead to DIC has resulted in novel preventive and

  13. Clinical Utility of Ultrasound Measurements of Plantar Fascia Width and Cross-Sectional AreaA Novel Technique.

    Science.gov (United States)

    Bisi-Balogun, Adebisi; Rector, Michael

    2017-09-01

    We sought to develop a standardized protocol for ultrasound (US) measurements of plantar fascia (PF) width and cross-sectional area (CSA), which may serve as additional outcome variables during US examinations of both healthy asymptomatic PF and in plantar fasciopathy and determine its interrater and intrarater reliability. Ten healthy individuals (20 feet) were enrolled. Participants were assessed twice by two raters each to determine intrarater and interrater reliability. For each foot, three transverse scans of the central bundle of the PF were taken at its insertion at the medial calcaneal tubercle, identified in real time on the plantar surface of the foot, using a fine wire technique. Reliability was determined using intraclass correlation coefficients (ICC), standard errors of measurement (SEM), and limits of agreement (LOA) expressed as percentages of the mean. Reliability of PF width and CSA measurements was determined using PF width and CSA measurements from one sonogram measured once and the mean of three measurements from three sonograms each measured once. Ultrasound measurements of PF width and CSA showed a mean of 18.6 ± 2.0 mm and 69.20 ± 13.6 mm 2 respectively. Intra-reliability within both raters showed an ICC > 0.84 for width and ICC > 0.92 for CSA as well as a SEM% and LOA% < 10% for both width and CSA. Inter-rater reliability showed an ICC of 0.82 for width and 0.87 for CSA as well as a SEM% and LOA% < 10% for width and a SEM% < 10% and LOA% < 20% for CSA. Relative and absolute reliability within and between raters were higher when using the mean of three sonographs compared to one sonograph. Using this novel technique, PF CSA and width may be determined reliably using measurements from one sonogram or the mean of three sonograms. Measurement of PF CSA and width in addition to already established thickness and echogenicity measurements provides additional information on structural properties of the PF for clinicians and researchers in healthy

  14. Emergency treatment by intravascular embolization in traumatic carotid cavernous fistula

    International Nuclear Information System (INIS)

    Tang Jun; Sun Zengtao; Liu Zuoqin; Liu Yanjun; Li Fengxin

    2006-01-01

    Objective: To discuss the method of intervenfional intravascular treatment in traumatic carotid cavernous fistula (TCCF) and the significance of clinical application in emergency. Methods: In 297 eases of TCCF, 36 cases were treated by interventional intravascular embolization by detachable balloon, embolization orificium or occlusion in one side of carotid artery. In the 36 cases, serious epistaxis occurred in 22 eases, cortical vein inflow in 9 cases, intracranial hemorrhage in 3 cases, aggravation of eyesight in 3 cases, and limb dysfunction in 2 cases. Results: Fistula was successfully embolized and internal carotid artery remained patent in 19 cases. Complete embolization of orificium or internal carotid artery was achieved in 17 eases. The serious epistaxias in 22 cases and intracranial hemorrhage in 3 cases stopped. Eyesight recovered in 2 eases and improved in 1 case. Limb dysfunction improved evidently in 2 cases. Conclusion: Intravascular embolization treatment is the first therapeutic choice for TCCF, especially in emergency. It is necessary, safe and effective. (authors)

  15. Reliability and validity of the ultrasound technique to measure the rectus femoris muscle diameter in older CAD-patients

    Directory of Open Access Journals (Sweden)

    Thomaes Tom

    2012-04-01

    Full Text Available Abstract Background The increasing age of coronary artery disease (CAD patients and the occurrence of sarcopenia in the elderly population accompanied by 'fear of moving' and hospitalization in these patients often results in a substantial loss of skeletal muscle mass and muscle strength. Cardiac rehabilitation can improve exercise tolerance and muscle strength in CAD patients but less data describe eventual morphological muscular changes possibly by more difficult access to imaging techniques. Therefore the aim of this study is to assess and quantify the reliability and validity of an easy applicable method, the ultrasound (US technique, to measure the diameter of rectus femoris muscle in comparison to the muscle dimensions measured with CT scans. Methods 45 older CAD patients without cardiac event during the last 9 months were included in this study. 25 patients were tested twice with ultrasound with a two day interval to assess test-retest reliability and 20 patients were tested twice (once with US and once with CT on the same day to assess the validity of the US technique compared to CT as the gold standard. Isometric and isokinetic muscle testing was performed to test potential zero-order correlations between muscle diameter, muscle volume and muscle force. Results An intraclass correlation coefficient (ICC of 0.97 ((95%CL: 0.92 - 0.99 was found for the test-retest reliability of US and the ICC computed between US and CT was 0.92 (95%CL: 0.81 - 0.97. The absolute difference between both techniques was 0.01 ± 0.12 cm (p = 0.66 resulting in a typical percentage error of 4.4%. Significant zero-order correlations were found between local muscle volume and muscle diameter assessed with CT (r = 0.67, p = 0.001 and assessed with US (r = 0.49, p Conclusions Ultrasound imaging can be used as a valid and reliable measurement tool to assess the rectus femoris muscle diameter in older CAD patients.

  16. A comparison of ultrasound measurements to assess carotid atherosclerosis development in subjects with and without type 2 diabetes

    Directory of Open Access Journals (Sweden)

    Zinman Bernard

    2005-06-01

    Full Text Available Abstract Background Subjects with type 2 diabetes are at an increased risk of vascular complications. The use of carotid ultrasound remains an attractive, non-invasive method to monitor atherosclerotic disease progression and/or response to treatment in patients with type 2 diabetes, with intima-media thickness routinely used as the gold standard to detect pathology. However, alternative measurements, such as plaque area or volume, may represent a potentially more powerful approach. Thus, the objective of this study was to compare the traditional intima-media thickness measurement against the novel total plaque volume measurement in analyzing carotid atherosclerosis development in individuals with type 2 diabetes. Methods The case-control study included 49 Oji-Cree adults with diabetes or impaired glucose tolerance, aged 21–69, and 49 sex- and age-matched normoglycemic subjects. At baseline, metabolic variables were measured, including body mass index, waist circumference, total cholesterol:high density lipoprotein ratio, plasma triglycerides, plasma glucose, and serum insulin. Carotid ultrasound measurements, 7 years later, assessed carotid arterial intima-media thickness and total plaque volume. Results At baseline, the two groups were well matched for smoking habits, hypertension, body mass index, and waist circumference. Differences were noted in baseline measurements of total cholesterol:high density lipoprotein (P = 0.0006, plasma triglycerides (P P P = 0.037, but not intima-media thickness measurements, were higher in subjects with diabetes/impaired glucose tolerance compared to the normoglycemic controls. Correlation between intima-media thickness and total plaque volume was moderate. Based on our study findings, to achieve power levels >0.70 when comparing intima-media thickness measurements for diabetics versus non-diabetics, thousands of study subjects are required. For comparing total plaque volume measurements, only hundreds of

  17. Intravascular application of electrocautery in a rabbit model of abdominal aortic endarterectomy.

    Science.gov (United States)

    Wang, Chuan; Xin, Yi; Li, Na; Li, Diankun; Li, Jingxing; Gu, Chengxiong

    2017-07-01

    Effective therapies for preventing perioperative complications such as thrombosis and inflammation after coronary endarterectomy (CE) are lacking. Electrocoagulation electrotomes have been routinely used in surgery for their cutting, clotting, and hemostatic properties. As strong flattening tools, their electrocautery function may prevent mechanical intimal-adventitial injury to arterial circulation and attenuate stenosis. The present study investigated the effects of intravascular application of electrocautery on ameliorating inflammation and thrombosis in a rabbit model of abdominal aortic endarterectomy. New Zealand rabbits were randomly divided into the sham, control (endarterectomy), and study (endarterectomy + electrocautery) groups with 10 in each group. Abdominal aortas were partially blocked and intima was removed. Electrocautery was performed with an electrocoagulation electrotome through the entire blocked vessel lumen. Vascular ultrasound parameters, molecular biological and histological characteristics of the abdominal aorta including vascular diameter, blood flow velocity, serum interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) levels, and apoptosis rate of vascular endothelial cells (ECs) were evaluated postoperatively by vascular Doppler ultrasound, ELISA, real-time RT-PCR, flow cytometry, and immunofluorescence at various time points. Compared with the endarterectomy + electrocautery group, the isolated endarterectomy group had significantly increased levels and gene expression of TNF-α and IL-6 (Pelectrocautery has favorable short-term effects on the abdominal aorta and can reduce inflammation in a rabbit model of abdominal aorta endarterectomy. Long-term anti-inflammatory and anti-thrombotic effects on arterial remodeling and the clinical value of electrocautery in CE remain to be determined.

  18. Comparison and evaluation of indicator dilution models for bolus of ultrasound contrast agents

    Czech Academy of Sciences Publication Activity Database

    Harabis, V.; Kolář, R.; Mézl, M.; Jiřík, Radovan

    2013-01-01

    Roč. 34, č. 2 (2013), s. 151-162 ISSN 0967-3334 R&D Projects: GA ČR GAP102/12/2380 Institutional support: RVO:68081731 Keywords : perfusion model * ultrasound * contrast agent * intravascular perfusion * tissue phantom Subject RIV: FS - Medical Facilities ; Equipment Impact factor: 1.617, year: 2013

  19. Ultrasound -- Pelvis

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    Full Text Available ... diagnose symptoms experienced by women such as: pelvic pain abnormal vaginal bleeding other menstrual problems Ultrasound exams ... pelvic ultrasound can help evaluate: pelvic masses pelvic pain ambiguous genitalia and anomalies of pelvic organs early ...

  20. Prostate Ultrasound

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    Full Text Available ... pictures of a man’s prostate gland and to help diagnose symptoms such as difficulty urinating or an ... Ultrasound imaging is a noninvasive medical test that helps physicians diagnose and treat medical conditions. Prostate ultrasound, ...

  1. Ultrasound -- Pelvis

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  2. Ultrasound -- Pelvis

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    Full Text Available ... internal organs, as well as blood flowing through blood vessels. Ultrasound imaging is a noninvasive medical test that helps physicians diagnose and treat medical conditions. There are three types of pelvic ultrasound: abdominal ( transabdominal ) vaginal ( transvaginal / endovaginal ) ...

  3. Ultrasound -- Pelvis

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    Full Text Available ... There are three types of pelvic ultrasound: abdominal, vaginal (for women), and rectal (for men). These exams ... are three types of pelvic ultrasound: abdominal ( transabdominal ) vaginal ( transvaginal / endovaginal ) for women rectal ( transrectal ) for men ...

  4. Ultrasound -- Pelvis

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    Full Text Available ... the procedure? In women, a pelvic ultrasound is most often performed to evaluate the: uterus cervix ovaries ... page How is the procedure performed? Transabdominal: For most ultrasound exams, you will be positioned lying face- ...

  5. Ultrasound -- Pelvis

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    Full Text Available ... is used to evaluate the: bladder seminal vesicles prostate Transrectal ultrasound, a special study usually done to provide detailed evaluation of the prostate gland, involves inserting a specialized ultrasound transducer into ...

  6. Ultrasound -- Pelvis

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  7. Prostate Ultrasound

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  8. Ultrasound -- Pelvis

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  9. Ultrasound -- Pelvis

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    Full Text Available ... ovarian cysts and uterine fibroids ovarian or uterine cancers A transvaginal ultrasound is usually performed to view the endometrium (the lining of the uterus) and the ovaries. Transvaginal ultrasound also evaluates the myometrium (muscular walls ...

  10. Prostate Ultrasound

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    Full Text Available ... those sound waves to create an image. Ultrasound examinations do not use ionizing radiation (as used in ... abnormal masses, such as tumors. In an ultrasound examination, a transducer both sends the sound waves into ...

  11. Ultrasound -- Pelvis

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  12. Prostate Ultrasound

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  13. Ultrasound -- Pelvis

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  14. Prostate Ultrasound

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  15. Ultrasound -- Pelvis

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  16. Prostate Ultrasound

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  17. Ultrasound -- Pelvis

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    Full Text Available ... Imaging? Ultrasound waves are disrupted by air or gas; therefore ultrasound is not an ideal imaging technique ... page Additional Information and Resources RTAnswers.org Radiation Therapy for Gynecologic Cancers Radiation Therapy for Prostate Cancer ...

  18. Prostate Ultrasound

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  19. Prostate Ultrasound

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  20. Ultrasound -- Pelvis

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    Full Text Available ... investigation of the uterine cavity . Three-dimensional (3-D) ultrasound permits evaluation of the uterus and ovaries ... abnormal uterine bleeding Some physicians also use 3-D ultrasound or sonohysterography for patients with infertility. In ...

  1. Prostate Ultrasound

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    Full Text Available ... and produces pictures of the inside of the body using sound waves. Ultrasound imaging, also called ultrasound ... from the probe through the gel into the body. The transducer collects the sounds that bounce back ...

  2. Ultrasound -- Pelvis

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    Full Text Available ... and produces pictures of the inside of the body using sound waves. Ultrasound imaging, also called ultrasound ... from the probe through the gel into the body. The transducer collects the sounds that bounce back ...

  3. Ultrasound -- Pelvis

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    Full Text Available ... object is solid or filled with fluid). In medicine, ultrasound is used to detect changes in appearance, ... have special pediatric considerations. The teddy bear denotes child-specific content. Related Articles and Media Sonohysterography Ultrasound - ...

  4. Obstetrical Ultrasound

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    ... heartbeat can be seen as an ongoing ultrasound movie. Ultrasound devices also use Doppler, a special application ... the possible charges you will incur. Web page review process: This Web page is reviewed regularly by ...

  5. Ultrasound -- Pelvis

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  6. Ultrasound -- Pelvis

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    Full Text Available ... menstrual problems Ultrasound exams also help identify: palpable masses such as ovarian cysts and uterine fibroids ovarian ... In children, pelvic ultrasound can help evaluate: pelvic masses pelvic pain ambiguous genitalia and anomalies of pelvic ...

  7. Prostate Ultrasound

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  8. Ultrasound -- Pelvis

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  9. Ultrasound -- Pelvis

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  10. Ultrasound -- Pelvis

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  11. Ultrasound -- Pelvis

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  12. Ultrasound -- Pelvis

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    Full Text Available ... transducer sends out high-frequency sound waves (that the human ear cannot hear) into the body and then ... ultrasound , there are no known harmful effects on humans. top of page What are the limitations of Pelvic Ultrasound Imaging? Ultrasound waves are ...

  13. Stress predicts the trajectory of wound healing in living kidney donors as measured by high-resolution ultrasound.

    Science.gov (United States)

    Maple, Hannah; Chilcot, Joseph; Lee, Vanessa; Simmonds, Shanique; Weinman, John; Mamode, Nizam

    2015-01-01

    Psychological stress has been shown to be an influential factor on the rate of wound healing; however these findings have been demonstrated predominantly on artificially created wounds. Due to the absence of major co-morbidities, living kidney donors are a unique group in which to study this relationship. This study investigated the effect of preoperative stress and personality on surgical wound healing through the use of high-resolution ultrasound. Living kidney donors due to undergo a hand-assisted laparoscopic donor nephrectomy were asked to complete the Perceived Stress Scale, the Life Orientation Test-Revised and the Ten Item Personality Inventory prior to surgery. High-resolution ultrasound scans of surgical wounds were performed on the first three post-operative days and once following discharge (mean=15.3 days; s.d. 2.8). Two measurements from each image were obtained: wound width (size of wound) and median intensity (a marker of tissue fluid). Latent Growth Curve Models (LGCMs) were used to evaluate wound healing. 52 living kidney donors participated. Higher pre-operative life stress, lower optimism and lower conscientiousness were associated with delayed wound healing in living kidney donors for both outcomes. Increased emotional stability was associated with faster wound healing as demonstrated by a change in median intensity. Possible confounding factors, such as age, BMI, smoking status, local anaesthetic use and wound drain placement were not influential. This study, which measured wound healing in a novel patient sample using a novel technique, has demonstrated a negative association between stress and wound healing and the positive influence of optimism, conscientiousness and emotional stability. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Subclinical Synovitis Measured by Ultrasound in Rheumatoid Arthritis Patients With Clinical Remission Induced by Synthetic and Biological Modifying Disease Drugs.

    Science.gov (United States)

    Cruces, Marcos; Al Snih, Soham; Serra-Bonett, Natalí; Rivas, Juan C

    2017-10-09

    Rheumatoid arthritis (RA) patients with disease in clinical remission might show subclinical synovitis, which can be related to the progress of structural joint damage. To determine and compare the degree of synovial inflammation by ultrasound (US) in patients with RA in clinical remission, treated with DMARD or combination therapy with DMARD and anti-TNF. Hospital-based cross-sectional study of 58 patients with RA in sustained remission for at least 6 months by DAS28 <2.6, who attended the Rheumatology Service at the Hospital Universitario de Caracas. Patients underwent clinical, functional, and laboratory assessments. Ultrasound was performed in hands measuring synovial effusion, synovial hypertrophy and power Doppler signal; using a semiquantitative 4-point scale of 0=none to 3=severe. Chi-square and t-test were used to compare the clinical, functional, laboratory and US assessments between the DMARD (N=37) and combination therapy with DMARD and anti-TNF (N=21) groups. A p-value <0.05 was considered statistically significant. Out of 58 patients, 25.9% had remission by US and 74.1% had synovial effusion or hypertrophy or positive power Doppler signal. Non-significant differences in US synovitis between the two groups were found. Persistent US activity was evident in a high percentage of rheumatoid arthritis patients in clinical remission by DAS28. No differences in subclinical synovitis measured by US were found between patients with DMARD and anti-TNF-induced clinical remission. Copyright © 2017 Elsevier España, S.L.U. and Sociedad Española de Reumatología y Colegio Mexicano de Reumatología. All rights reserved.

  15. Quantitative measurement of portal blood flow by magnetic resonance phase contrast. Comparative study of flow phantom and Doppler ultrasound in vivo

    International Nuclear Information System (INIS)

    Tsunoda, Masatoshi; Kimoto, Shin; Hamazaki, Keisuke; Takeda, Yoshihiro; Hiraki, Yoshio.

    1994-01-01

    A non-invasive method for measuring portal blood flow by magnetic resonance (MR) phase contrast was evaluated in a flow phantom and 20 healthy volunteers. In a flow phantom study, the flow volumes and mean flow velocities measured by MR phase contrast showed close correlations with those measured by electromagnetic flow-metry. In 20 healthy volunteers, the cross-sectional areas, flow volumes and mean flow velocities measured by MR phase contrast correlated well with those measured by the Doppler ultrasound method. Portal blood flow averaged during the imaging time could be measured under natural breathing conditions by using a large number of acquisitions without the limitations imposed on the Doppler ultrasound method. MR phase contrast is considered to be useful for the non-invasive measurement of portal blood flow. (author)

  16. General Ultrasound Imaging

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    Full Text Available ... collects the sounds that bounce back and a computer then uses those sound waves to create an ... types of Doppler ultrasound: Color Doppler uses a computer to convert Doppler measurements into an array of ...

  17. General Ultrasound Imaging

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    Full Text Available ... biopsies , in which needles are used to sample cells from an abnormal area for laboratory testing. image ... ultrasound, measures the direction and speed of blood cells as they move through vessels. The movement of ...

  18. General Ultrasound Imaging

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    Full Text Available ... kidneys. There are three types of Doppler ultrasound: Color Doppler uses a computer to convert Doppler measurements into an array of colors to show the speed and direction of blood ...

  19. The effect of recumbency position on the ultrasound measurement of the canine adrenal gland in non-adrenal gland illness

    Directory of Open Access Journals (Sweden)

    Rose AM

    2017-11-01

    Full Text Available Anne Marie Rose,1 Thurid Johnstone,1,2 Sue Finch,3 Cathy Beck1 1U-Vet Animal Hospital Werribee, The University of Melbourne, 2TRACTS Translational Research and Clinical Trial Study Group, The University of Melbourne, 3Statistical Consulting Centre, School of Mathematics and Statistics, The University of Melbourne, Melbourne, VIC, Australia Abstract: Abdominal ultrasound is frequently used to assess the canine adrenal gland (AG and subjective and objective features of normal AGs have been described. The effect of the dogs’ recumbency position on the accuracy of AG measurement acquisition is not known. This prospective study, performed in dogs with non-adrenal illness, compared ultrasonographic AG measurements made in dogs placed in dorsal recumbency with those made in left or right lateral recumbency. AG length, height and width measurements made in the longitudinal image plane, and height and width measurements from the transverse image plane were assessed. The level and limits of agreement between the dorsal and lateral recumbency for each of the measurements were determined using the Bland–Altman analysis. The measurement with the best agreement between the dorsal and lateral recumbency was the caudal pole thickness (CPT from the longitudinal image plane. Agreement between lateral and dorsal recumbency was poorer for the measurements derived from the transverse image plane and poorest for measurements of AG length in the longitudinal plane. This study demonstrates that there is some difference in the measurements acquired in dorsal compared with lateral recumbency; however, the difference is small for the CPT from the longitudinal plane. This finding suggests that the CPT from the longitudinal image plane is the most reliable measurement in terms of agreement between dorsal and lateral recumbency in dogs with non-AG illness. Keywords: adrenal glands, ultrasonography, normal, dog, recumbency

  20. Dynamic contrast enhanced ultrasound for therapy monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Hudson, John M. [Department of Medical Biophysics, University of Toronto, Toronto, ON (Canada); Williams, Ross [Imaging Research, Sunnybrook Research Institute, Toronto, ON (Canada); Tremblay-Darveau, Charles; Sheeran, Paul S. [Department of Medical Biophysics, University of Toronto, Toronto, ON (Canada); Milot, Laurent [Department of Medical Imaging, University of Toronto, Toronto, ON (Canada); Bjarnason, Georg A. [Department of Medical Oncology, University of Toronto, and Sunnybrook Odette Cancer Centre, Toronto, ON (Canada); Burns, Peter N., E-mail: burns@sri.utoronto.ca [Department of Medical Biophysics, University of Toronto, Toronto, ON (Canada); Imaging Research, Sunnybrook Research Institute, Toronto, ON (Canada); Department of Medical Imaging, University of Toronto, Toronto, ON (Canada)

    2015-09-15

    Quantitative imaging is a crucial component of the assessment of therapies that target the vasculature of angiogenic or inflamed tissue. Dynamic contrast-enhanced ultrasound (DCE-US) using microbubble contrast offers the advantages of being sensitive to perfusion, non-invasive, cost effective and well suited to repeated use at the bedside. Uniquely, it employs an agent that is truly intravascular. This papers reviews the principles and methodology of DCE-US, especially as applied to anti-angiogenic cancer therapies. Reproducibility is an important attribute of such a monitoring method: results are discussed. More recent technical advances in parametric and 3D DCE-US imaging are also summarised and illustrated.

  1. Comparison of Measurements of the Uterus and Cervix Obtained by Magnetic Resonance and Transabdominal Ultrasound Imaging to Identify the Brachytherapy Target in Patients With Cervix Cancer

    International Nuclear Information System (INIS)

    Dyk, Sylvia van; Kondalsamy-Chennakesavan, Srinivas; Schneider, Michal; Bernshaw, David; Narayan, Kailash

    2014-01-01

    Purpose: To compare measurements of the uterus and cervix obtained with magnetic resonance imaging (MRI) and transabdominal ultrasound to determine whether ultrasound can identify the brachytherapy target and be used to guide conformal brachytherapy planning and treatment for cervix cancer. Methods and Materials: Consecutive patients undergoing curative treatment with radiation therapy between January 2007 and March 2012 were included in the study. Intrauterine applicators were inserted into the uterine canal while patients were anesthetized. Images were obtained by MRI and transabdominal ultrasound in the longitudinal axis of the uterus with the applicator in treatment position. Measurements were taken at the anterior and posterior surface of the uterus at 2.0-cm intervals along the applicator, from the external os to the tip of the applicator. Data were analyzed using Bland Altman plots examining bias and 95% limits of agreement. Results: A total of 192 patients contributed 1668 measurements of the cervix and uterus. Mean (±SD) differences of measurements between imaging modalities at the anterior and posterior uterine surface ranged from 1.5 (±3.353) mm to 3.7 (±3.856) mm, and −1.46 (±3.308) mm to 0.47 (±3.502) mm, respectively. The mean differences were less than 3 mm in the cervix. The mean differences were less than 1.5 mm at all measurement points on the posterior surface. Conclusion: Differences in the measurements of the cervix and uterus obtained by MRI and ultrasound were within clinically acceptable limits. Transabdominal ultrasound can be substituted for MRI in defining the target volume for conformal brachytherapy treatment of cervix cancer

  2. Comparison of Measurements of the Uterus and Cervix Obtained by Magnetic Resonance and Transabdominal Ultrasound Imaging to Identify the Brachytherapy Target in Patients With Cervix Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Dyk, Sylvia van, E-mail: sylvia.vandyk@petermac.org [Radiation Therapy Services, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Kondalsamy-Chennakesavan, Srinivas [Rural Clinical School, University of Queensland, Toowoomba, Queensland (Australia); Schneider, Michal [Department of Medical Imaging and Radiation Science, Monash University, Clayton, Victoria (Australia); Bernshaw, David [Division of Radiation Oncology, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Narayan, Kailash [Division of Radiation Oncology, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Department of Obstetrics and Gynaecology, Melbourne University, Melbourne, Victoria (Australia)

    2014-03-15

    Purpose: To compare measurements of the uterus and cervix obtained with magnetic resonance imaging (MRI) and transabdominal ultrasound to determine whether ultrasound can identify the brachytherapy target and be used to guide conformal brachytherapy planning and treatment for cervix cancer. Methods and Materials: Consecutive patients undergoing curative treatment with radiation therapy between January 2007 and March 2012 were included in the study. Intrauterine applicators were inserted into the uterine canal while patients were anesthetized. Images were obtained by MRI and transabdominal ultrasound in the longitudinal axis of the uterus with the applicator in treatment position. Measurements were taken at the anterior and posterior surface of the uterus at 2.0-cm intervals along the applicator, from the external os to the tip of the applicator. Data were analyzed using Bland Altman plots examining bias and 95% limits of agreement. Results: A total of 192 patients contributed 1668 measurements of the cervix and uterus. Mean (±SD) differences of measurements between imaging modalities at the anterior and posterior uterine surface ranged from 1.5 (±3.353) mm to 3.7 (±3.856) mm, and −1.46 (±3.308) mm to 0.47 (±3.502) mm, respectively. The mean differences were less than 3 mm in the cervix. The mean differences were less than 1.5 mm at all measurement points on the posterior surface. Conclusion: Differences in the measurements of the cervix and uterus obtained by MRI and ultrasound were within clinically acceptable limits. Transabdominal ultrasound can be substituted for MRI in defining the target volume for conformal brachytherapy treatment of cervix cancer.

  3. 21 CFR 880.5440 - Intravascular administration set.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Intravascular administration set. 880.5440 Section 880.5440 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL HOSPITAL AND PERSONAL USE DEVICES General Hospital and Personal Use...

  4. Heartbeat OCT: In vivo intravascular megahertz-optical coherence tomography

    NARCIS (Netherlands)

    T. Wang (Tianshi); A.F.H. Pfeiffer (Andreas); E.S. Regar (Eveline); W. Wieser (Wolfgang); H.M.M. van Beusekom (Heleen); C.T. Lancée (Charles); T. Springeling (Tirza); I. Krabbendam (Ilona); A.F.W. van der Steen (Ton); R. Huber (Roman); G. van Soest (Gijs)

    2015-01-01

    textabstractCardiac motion artifacts, non-uniform rotational distortion and undersampling affect the image quality and the diagnostic impact of intravascular optical coherence tomography (IV-OCT). In this study we demonstrate how these limitations of IV-OCT can be addressed by using an imaging

  5. Intravascular catheter related infections in children admitted on the ...

    African Journals Online (AJOL)

    peripheral venous intravascular catheters uncoated with no antibiotic or antiseptic, was done. Social demographic characteristics, anthropometry, clinical examination including the catheter site were determined at enrollment. The children had their blood, catheter tip and hub samples taken off for culture and sensitivity as ...

  6. Disseminated intravascular coagulation in meningococcal sepsis. Case 7

    NARCIS (Netherlands)

    Zeerleder, S.; Zürcher Zenklusen, R.; Hack, C. E.; Wuillemin, W. A.

    2003-01-01

    We report on a man (age: 49 years), who died from severe meningococcal sepsis with disseminated intravascular coagulation (DIC), multiple organ dysfunction syndrome and extended skin necrosis. We discuss in detail the pathophysiology of the activation of coagulation and fibrinolysis during sepsis.

  7. Intravascular catheter sepsis | Mer | South African Medical Journal

    African Journals Online (AJOL)

    Intravascular devices are an integral component of modern-day medical practice. They are used to administer intravenous fluids, medications, blood products and parenteral nutrition. In addition, they serve as a valuable monitor of the haemodynamic status of critically ill patients.

  8. Initial evaluation of an ultrasound measure for assessing the activity of skin lesions in juvenile localized scleroderma.

    Science.gov (United States)

    Li, S C; Liebling, M S; Haines, K A; Weiss, J E; Prann, A

    2011-05-01

    To evaluate the construct validity of 2 proposed measures (the Ultrasound Disease Activity [U-DA] and the Tissue Thickness Score [TTS]) for evaluating sonographic differences in juvenile localized scleroderma skin lesions. We conducted a retrospective review of juvenile localized scleroderma patients who had ultrasound scans of their skin lesions between October 2005 and February 2009. Imaged lesions were classified as active or inactive based upon clinical assessment. Lesions had to have been imaged within 1 month of a clinic visit or have the same clinical assessment during both the visit before and the visit after the scan. Two physicians scored the scans using the U-DA, which scores for differences in lesion echogenicity and vascularity compared with normal tissue. Tissue thickness differences were evaluated by percent differences and by using the TTS. Wilcoxon's rank sum test was performed to assess differences. We studied 52 scans from 21 patients, 32 scans of active skin lesions and 20 scans of inactive skin lesions. Features reported by clinicians as indicative of active disease included erythema, warmth, violaceous color, new lesion, expansion of lesion, and induration. The U-DA was significantly different between active and inactive skin lesions (P = 0.0010) with significant differences found for the parameters of total echogenicity, hypodermis echogenicity, and deep tissue layer vascularity (P = 0.0014, P = 0.0023, and P = 0.0374, respectively). No significant differences were found for tissue layer thickness or TTS. The U-DA may be a useful tool in the identification of localized scleroderma activity. Further study is needed to prospectively evaluate the validity, reliability, and sensitivity of this potential monitoring tool. Copyright © 2011 by the American College of Rheumatology.

  9. Length and volume of morphologically normal kidneys in Korean Children: Ultrasound measurement and estimation using body size

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jun Hwee; Kim, Myung Joon; Lim, Sok Hwan; Lee, Mi Jung [Dept. of Radiology and Research Institute of Radiological Science, Severance Children' s Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of); Kim, Ji Eun [Biostatistics Collaboration Unit, Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2013-08-15

    To evaluate the relationship between anthropometric measurements and renal length and volume measured with ultrasound in Korean children who have morphologically normal kidneys, and to create simple equations to estimate the renal sizes using the anthropometric measurements. We examined 794 Korean children under 18 years of age including a total of 394 boys and 400 girls without renal problems. The maximum renal length (L) (cm), orthogonal anterior-posterior diameter (D) (cm) and width (W) (cm) of each kidney were measured on ultrasound. Kidney volume was calculated as 0.523 x L x D x W (cm{sup 3}). Anthropometric indices including height (cm), weight (kg) and body mass index (m{sup 2}/kg) were collected through a medical record review. We used linear regression analysis to create simple equations to estimate the renal length and the volume with those anthropometric indices that were mostly correlated with the US-measured renal sizes. Renal length showed the strongest significant correlation with patient height (R2, 0.874 and 0.875 for the right and left kidneys, respectively, p < 0.001). Renal volume showed the strongest significant correlation with patient weight (R2, 0.842 and 0.854 for the right and left kidneys, respectively, p < 0.001). The following equations were developed to describe these relationships with an estimated 95% range of renal length and volume (R2, 0.826-0.884, p < 0.001): renal length = 2.383 + 0.045 x Height (± 1.135) and = 2.374 + 0.047 x Height (± 1.173) for the right and left kidneys, respectively; and renal volume 7.941 + 1.246 x Weight (± 15.920) and = 7.303 + 1.532 x Weight (± 18.704) for the right and left kidneys, respectively. Scatter plots between height and renal length and between weight and renal volume have been established from Korean children and simple equations between them have been developed for use in clinical practice.

  10. Length and volume of morphologically normal kidneys in Korean Children: Ultrasound measurement and estimation using body size

    International Nuclear Information System (INIS)

    Kim, Jun Hwee; Kim, Myung Joon; Lim, Sok Hwan; Lee, Mi Jung; Kim, Ji Eun

    2013-01-01

    To evaluate the relationship between anthropometric measurements and renal length and volume measured with ultrasound in Korean children who have morphologically normal kidneys, and to create simple equations to estimate the renal sizes using the anthropometric measurements. We examined 794 Korean children under 18 years of age including a total of 394 boys and 400 girls without renal problems. The maximum renal length (L) (cm), orthogonal anterior-posterior diameter (D) (cm) and width (W) (cm) of each kidney were measured on ultrasound. Kidney volume was calculated as 0.523 x L x D x W (cm 3 ). Anthropometric indices including height (cm), weight (kg) and body mass index (m 2 /kg) were collected through a medical record review. We used linear regression analysis to create simple equations to estimate the renal length and the volume with those anthropometric indices that were mostly correlated with the US-measured renal sizes. Renal length showed the strongest significant correlation with patient height (R2, 0.874 and 0.875 for the right and left kidneys, respectively, p < 0.001). Renal volume showed the strongest significant correlation with patient weight (R2, 0.842 and 0.854 for the right and left kidneys, respectively, p < 0.001). The following equations were developed to describe these relationships with an estimated 95% range of renal length and volume (R2, 0.826-0.884, p < 0.001): renal length = 2.383 + 0.045 x Height (± 1.135) and = 2.374 + 0.047 x Height (± 1.173) for the right and left kidneys, respectively; and renal volume 7.941 + 1.246 x Weight (± 15.920) and = 7.303 + 1.532 x Weight (± 18.704) for the right and left kidneys, respectively. Scatter plots between height and renal length and between weight and renal volume have been established from Korean children and simple equations between them have been developed for use in clinical practice.

  11. A Comparison of Ultrasound and MRI Measurements of the Cross-Sectional Area of the Median Nerve at the Wrist.

    Science.gov (United States)

    Hersh, Beverly; D'Auria, Jennifer; Scott, Michael; Fowler, John R

    2018-05-01

    Ultrasound (US) measurement of cross-sectional area (CSA) of the median nerve has emerged as a viable alternative to electromyography/nerve conduction studies (EMG/NCS) for diagnosis of carpal tunnel syndrome (CTS). The purpose of this study is to compare CSA of the median nerve between US and MRI using current MRI and US technology. The null hypothesis is there is no difference between US and MRI CSA measurements. The study design was an observational cohort, enrolling patients presenting to clinic with MRI of the wrist. Participants with clinical signs and symptoms of CTS were excluded. The CSA measurements of the median nerve on MRI T1-weighted axial images were performed by a hand fellow blinded to results of US measurements, and US measurement of median nerve CSA was performed by a hand fellowship trained surgeon blinded to results of the MRI measurements. Results were analyzed via percent error, Pearson correlation, and t tests. Twenty participants were enrolled with mean age of 29.4 years. Four left wrists and 16 right wrists were measured. The US mean CSA of the median nerve was 6.8 mm 2 (±2.330 mm 2 ). The MRI mean CSA of the median nerve was 6.8 mm 2 (±2.153 mm 2 ), P = .442. Pearson correlation between modalities was 0.93, suggesting near-perfect correlation. Mean percent error was 8.8%. Results of this study suggest that US is an accurate method to measure CSA of the median nerve at the carpal tunnel inlet. The mean difference between US and MRI was unlikely to be clinically significant.

  12. [Size of testes and epididymes in boys up to 17 years of life assessed by ultrasound method and method of external linear measurements].

    Science.gov (United States)

    Osemlak, Paweł

    2011-01-01

    1. Determination of the size of testes and epididymes on the right and left side, in healthy boys in various age groups with use of non-invasive ultrasound examination method and the method of external linear measurements. 2. Determination of age, when intensive growth of testicular and epididymal size starts. 3. Determination whether there are statistically significant differences between the size of the right and the left testis, as well as between the right and left epididymis. 4. Evaluation of the ultrasound method and method of external linear measurements in their use for scientific investigations. 309 boys, aged from 1 day to 17 years of life, treated in the Clinical Department of Paediatric Surgery and Traumatology of the Medical University in Lublin from 2009 to 2010 due to diseases needed to be treated surgically, but not the scrotum, were examined in this study. No pathologies influencing the development of genital organs were found in these boys. Dimension of the testes was studied with ultrasound method and with method of external linear measurements. Dimension of epididymes was only examined with ultrasound method. In every age group the author calculated mean arithmetical values for: testiscular length, thickness, width and volume, as well as epididymal depth and basis. With consideration of standard deviation (X+/-1 SD) it was possible to define the range of dimension of healthy testes and epididymes and their change with age. Final dimensions of the right and left testis as well as of the right and left epididymis were compared. Dimensions of the testis on the same side of body acquired with the ultrasound method and acquired with the method of external linear measurements were compared. Statistical work-up with Wilcoxon test for two dependent groups was implemented. Ultrasound evaluation pointed to intensive 2.5-times increase in testicular length and width, and 2-times increase in testicular thickness in boys aged 10 to 17 years. Mean volume of

  13. [Ultrasound measurement of fetal posterior fossa at 11 to 13⁺⁶ gestational weeks for screening open spina bifida].

    Science.gov (United States)

    Qin, Feng-Zhen; Li, Sheng-Li; Wen, Hua-Xuan; Ouyang, Yu-Rong; Zheng, Qiong; Bi, Jing-Ru

    2014-06-01

    To establish the normal reference ranges of transabdominal ultrasound measurements of the posterior fossa structure in fetuses at 11 to 13⁺⁶ gestational weeks and explore their clinical value in screening open spina bifida (OSB). Between January, 2013 and September, 541 randomly selected normal fetuses underwent nuchal translucency at the gestational age 11 to 13⁺⁶ weeks. The parameters of the posterior fossa were measured in mid-sagittal view of the fetal face and the axial view of the transverse cerebellum insonated through the anterior fontanel by transabdominal ultrasound to establish the normal reference ranges. The measurements were obtained from 3 fetuses with OSB for comparison with the reference ranges. In normal fetuses, the parameters of the posterior fossa measured in the two views showed no significant differences (P>0.05). Two high echogenic lines were observed in normal fetuses, as compared with one in fetuses with OSB representing the posterior border of the brain stem and the anterior border of the fourth ventricle. The line between the posterior border of the fourth ventricle and the anterior border of the cisterna magna was not displayed in fetuses with OSB. The anteroposterior diameters of the brain stem, the fourth ventricle, and cisterna magna all increased in positive correlation with the crown-lump length in normal fetuses. In the 3 OSB fetuses, the anteroposterior diameter of the brain stem exceeded the 95th percentile and the anteroposterior diameter of fourth ventrical-cisterner magena was below the 5th percentile of the reference range for CRL; the brain stem to fourth ventrical-cisterner magena anteroposterior diameter ratio was increased to above 1. The established normal reference ranges of the parameters of fetal posterior fossa may provide assistance in early OSB detection. The absence of the posterior border of the fourth ventricle and the anterior border of the cisterna magna and a brainstem to fourth ventrical

  14. Comparison between transcerebellar diameter with biparietal diameter of ultrasound for gestational age measurement in third trimester of pregnancy

    International Nuclear Information System (INIS)

    Naseem, F.; Fatima, N.; Yasmeen, S.; Saleem, S.

    2013-01-01

    To determine the frequency of correct assessment by transcerebeller diameter (TCD) versus biparietal diameter (BPD) for gestational age measurement at 36 weeks of pregnancy using first day of last menstrual period (LMP) for actual period of gestation. Study Design: Quasi experimental. Place and Duration of Study: Department of Obstetrics and Gynaecology, Bahawal Victoria Hospital, Bahawalpur from May to November 2010. Methodology: This study was performed on 228 patients at 36 weeks of pregnancy fulfilling the inclusion criteria. Ultrasound measurements of TCD and BPD was made and compared with LMP. Collected data was analyzed by SPSS version 10. Proportoin of correct diagnosis by each measurement was determined and compared using chi-square test with significance at p < 0.05. Results: Out of 228 patients, TCD was found to give correct assessment in 209 patients (91.7%; p = 0.001) corresponding to the gestational age by LMP i.e 36 weeks. BPD was found to give correct assessment corresponding to the gestational age by LMP in 176 patients (77.2%). Conclusion: Although both BPD and TCD are accurate biometric parameters at 36 weeks of gestation, transcerebellar diameter is more reliable method of gestational age determination in third trimester of pregnancy than biparietal diameter. TCD can be used as a tool to assist in the assessment of gestational age in third trimester. (author)

  15. An Improved Approach for Accurate and Efficient Measurement of Common Carotid Artery Intima-Media Thickness in Ultrasound Images

    Directory of Open Access Journals (Sweden)

    Qiang Li

    2014-01-01

    Full Text Available The intima-media thickness (IMT of common carotid artery (CCA can serve as an important indicator for the assessment of cardiovascular diseases (CVDs. In this paper an improved approach for automatic IMT measurement with low complexity and high accuracy is presented. 100 ultrasound images from 100 patients were tested with the proposed approach. The ground truth (GT of the IMT was manually measured for six times and averaged, while the automatic segmented (AS IMT was computed by the algorithm proposed in this paper. The mean difference ± standard deviation between AS and GT IMT is 0.0231 ± 0.0348 mm, and the correlation coefficient between them is 0.9629. The computational time is 0.3223 s per image with MATLAB under Windows XP on an Intel Core 2 Duo CPU E7500 @2.93 GHz. The proposed algorithm has the potential to achieve real-time measurement under Visual Studio.

  16. Estimation of Genetic Parameters for Real-time Ultrasound Measurements for Hanwoo Cows at Different Ages and Pregnancy Status

    Directory of Open Access Journals (Sweden)

    J. H. Lee

    2014-02-01

    Full Text Available The purpose of this study was to estimate genetic parameters of ultrasound measurements for longissimus dorsi muscle area (LMA, backfat thickness (BFT, and marbling score (MS in Hanwoo cows (N = 3,062 at the ages between 18 and 42 months. Data were collected from 100 Hanwoo breeding farms in Gyeongbuk province, Korea, in 2007 and 2008. The cows were classified into four different age groups, i.e. 18 to 22 months (the first pregnancy period, 23 to 27 (the first parturition, 28 to 32 (the second pregnancy, and 33 to 42 (the second parturition, respectively. For each age group, a multi-trait animal model was used to estimate variance components and heritabilities of the three traits. The averages of LMA, BFT, and MS measurements across the cows of all age groups were 50.1 cm2, 4.62 mm, and 3.04, respectively and heritability estimates were 0.09, 0.10, and 0.08 for the respective traits. However, when the data were analyzed in different age groups, heritability estimates of LMA and BFT were 0.24 and 0.47, respectively, for the cows of 18 to 22 months of age, and 0.21 for MS in the 28 to 32 months old cows. When the cows of all age groups were used, the estimates of genetic (phenotypic correlations were 0.43 (0.35, −0.06 (0.34 and 0.21 (0.32 between LMA and BFT, LMA and MS, and BFT and MS, respectively. However, in the cow age group between 28 and 32 (18 and 22 months, the estimates of genetic (phenotypic correlations were 0.05 (0.29, −0.15 (0.24 and 0.38 (0.24, for the respective pairs of traits. These results suggest that genetic, environmental, and phenotypic variations differ depending on cow age, such that care must be taken when ultrasound measurements are applied to selection of cows for meat quality.

  17. A novel method for measuring anterior segment area of the eye on ultrasound biomicroscopic images using photoshop.

    Directory of Open Access Journals (Sweden)

    Zhonghao Wang

    Full Text Available To describe a novel method for quantitative measurement of area parameters in ocular anterior segment ultrasound biomicroscopy (UBM images using Photoshop software and to assess its intraobserver and interobserver reproducibility.Twenty healthy volunteers with wide angles and twenty patients with narrow or closed angles were consecutively recruited. UBM images were obtained and analyzed using Photoshop software by two physicians with different-level training on two occasions. Borders of anterior segment structures including cornea, iris, lens, and zonules in the UBM image were semi-automatically defined by the Magnetic Lasso Tool in the Photoshop software according to the pixel contrast and modified by the observers. Anterior chamber area (ACA, posterior chamber area (PCA, iris cross-section area (ICA and angle recess area (ARA were drawn and measured. The intraobserver and interobserver reproducibilities of the anterior segment area parameters and scleral spur location were assessed by limits of agreement, coefficient of variation (CV, and intraclass correlation coefficient (ICC.All of the parameters were successfully measured by Photoshop. The intraobserver and interobserver reproducibilities of ACA, PCA, and ICA were good, with no more than 5% CV and more than 0.95 ICC, while the CVs of ARA were within 20%. The intraobserver and interobserver reproducibilities for defining the spur location were more than 0.97 ICCs. Although the operating times for both observers were less than 3 minutes per image, there was significant difference in the measuring time between two observers with different levels of training (p<0.001.Measurements of ocular anterior segment areas on UBM images by Photoshop showed good intraobserver and interobserver reproducibilties. The methodology was easy to adopt and effective in measuring.

  18. Diagnostic accuracy of fundal height and handheld ultrasound-measured abdominal circumference to screen for fetal growth abnormalities

    Science.gov (United States)

    Haragan, Adriane F.; Hulsey, Thomas C.; Hawk, Angela F.; Newman, Roger B.; Chang, Eugene Y.

    2015-01-01

    OBJECTIVE We sought to compare fundal height and handheld ultrasound–measured fetal abdominal circumference (HHAC) for the prediction of fetal growth restriction (FGR) or large for gestational age. STUDY DESIGN This was a diagnostic accuracy study in nonanomalous singleton pregnancies between 24 and 40 weeks’ gestation. Patients underwent HHAC and fundal height measurement prior to formal growth ultrasound. FGR was defined as estimated fetal weight less than 10%, whereas large for gestational age was defined as estimated fetal weight greater than 90%. Sensitivity and specificity were calculated and compared using methods described elsewhere. RESULTS There were 251 patients included in this study. HHAC had superior sensitivity and specificity for the detection of FGR (sensitivity, 100% vs 42.86%) and (specificity, 92.62% vs 85.24%). HHAC had higher specificity but lower sensitivity when screening for LGA (specificity, 85.66% vs 66.39%) and (sensitivity, 57.14% vs 71.43%). CONCLUSION HHAC could prove to be a valuable screening tool in the detection of FGR. Further studies are needed in a larger population. PMID:25818672

  19. Technical standards and guidelines: prenatal screening for Down syndrome that includes first-trimester biochemistry and/or ultrasound measurements.

    Science.gov (United States)

    Palomaki, Glenn E; Lee, Jo Ellen S; Canick, Jacob A; McDowell, Geraldine A; Donnenfeld, Alan E

    2009-09-01

    This statement is intended to augment the current general ACMG Standards and Guidelines for Clinical Genetics Laboratories and to address guidelines specific to first-trimester screening for Down syndrome. The aim is to provide the laboratory the necessary information to ensure accurate and reliable Down syndrome screening results given a screening protocol (e.g., combined first trimester and integrated testing). Information about various test combinations and their expected performance are provided, but other issues such as availability of reagents, patient interest in early test results, access to open neural tube defect screening, and availability of chorionic villus sampling are all contextual factors in deciding which screening protocol(s) will be selected by individual health care providers. Individual laboratories are responsible for meeting the quality assurance standards described by the Clinical Laboratory Improvement Act, the College of American Pathologists, and other regulatory agencies, with respect to appropriate sample documentation, assay validation, general proficiency, and quality control measures. These guidelines address first-trimester screening that includes ultrasound measurement and interpretation of nuchal translucency thickness and protocols that combine markers from both the first and second trimesters. Laboratories can use their professional judgment to make modification or additions.

  20. Measurement of the uterus and gestation sac by ultrasound in early normal and abnormal pregnancy.

    Science.gov (United States)

    Chandra, M; Evans, L J; Duff, G B

    1981-01-14

    Uterine volumes measured by two different ultrasonic methods, and gestation sac volumes in early normal pregnancy are reported. The results obtained for uterine volume measurements are compared. Methods using measurements obtained from only a longitudinal scan were simpler but slightly less accurate. Uterine volumes were also calculated in a series of patients with pregnancy complicated by threatened abortion. The accuracy of the prediction of the outcome of the pregnancy, based solely on uterine volume was 71 percent. Uterine volume measurement is most useful in identifying cases of missed abortion where the period of gestation is known.

  1. A novel method for measuring anterior segment area of the eye on ultrasound biomicroscopic images using photoshop.

    Science.gov (United States)

    Wang, Zhonghao; Liang, Xuanwei; Wu, Ziqiang; Lin, Jialiu; Huang, Jingjing

    2015-01-01

    To describe a novel method for quantitative measurement of area parameters in ocular anterior segment ultrasound biomicroscopy (UBM) images using Photoshop software and to assess its intraobserver and interobserver reproducibility. Twenty healthy volunteers with wide angles and twenty patients with narrow or closed angles were consecutively recruited. UBM images were obtained and analyzed using Photoshop software by two physicians with different-level training on two occasions. Borders of anterior segment structures including cornea, iris, lens, and zonules in the UBM image were semi-automatically defined by the Magnetic Lasso Tool in the Photoshop software according to the pixel contrast and modified by the observers. Anterior chamber area (ACA), posterior chamber area (PCA), iris cross-section area (ICA) and angle recess area (ARA) were drawn and measured. The intraobserver and interobserver reproducibilities of the anterior segment area parameters and scleral spur location were assessed by limits of agreement, coefficient of variation (CV), and intraclass correlation coefficient (ICC). All of the parameters were successfully measured by Photoshop. The intraobserver and interobserver reproducibilities of ACA, PCA, and ICA were good, with no more than 5% CV and more than 0.95 ICC, while the CVs of ARA were within 20%. The intraobserver and interobserver reproducibilities for defining the spur location were more than 0.97 ICCs. Although the operating times for both observers were less than 3 minutes per image, there was significant difference in the measuring time between two observers with different levels of training (pPhotoshop showed good intraobserver and interobserver reproducibilties. The methodology was easy to adopt and effective in measuring.

  2. Ultrasound -- Pelvis

    Medline Plus

    Full Text Available ... internal organs, as well as blood flowing through blood vessels. Ultrasound imaging is a noninvasive medical test that helps physicians diagnose and treat medical conditions. ...

  3. Repeatability of junctional zone measurements using three-dimensional transvaginal ultrasound in healthy, fertile women

    DEFF Research Database (Denmark)

    Rasmussen, Christina Kjærgaard; Glavind, Julie; Madsen, Lene Duch

    2016-01-01

    -observer repeatability was evaluated according to the Bland-Altman method and expressed as coefficient of repeatability (CoR). Results: Using 3D-TVS we visualised a thin and regular JZ in most women. The posterior uterine wall had the largest median (interquartile range; iqr) value of JZmax (5.2 (iqr 3.8-6.5)mm. Ten out....... Correlations between measurements were poor in the narrow range of JZ thickness. Conclusions: The JZ has an indistinct outline by 3D-TVS resulting in an error of JZ measurement within a broad range of ±2-4 mm, but reduced by average measurements. The thickness of JZ varied within a narrow range of this healthy......, fertile population and reliability measurements of JZ thickness has to be evaluated in women with a wider range of JZ thickness....

  4. Ultrasound measurement of rotator cuff thickness and acromio-humeral distance in the diagnosis of subacromial impingement syndrome of the shoulder.

    Science.gov (United States)

    Cholewinski, Jerzy J; Kusz, Damian J; Wojciechowski, Piotr; Cielinski, Lukasz S; Zoladz, Miroslaw P

    2008-04-01

    The usefulness of ultrasound measurements in the diagnosis of the subacromial impingement syndrome of the shoulder was evaluated. Fifty-seven patients with unilateral symptoms of the impingement syndrome underwent ultrasound examination of both shoulder joints, which included assessment of rotator cuff integrity, measurement of rotator cuff thickness and the distance between the infero-lateral edge of acromion and the apex of the greater tuberosity of humerus (AGT distance) in the standard ultrasonographic positions. As a control group, 36 volunteers (72 shoulders) with no history of shoulder pain were examined sonographically. Ultrasonographic assessment of humeral head elevation, measured as the AGT distance, proved to be useful in establishing the diagnosis of the subacromial impingement syndrome of the shoulder. A difference in rotator cuff thickness of more than 1.1 mm and a difference in the AGT distance of more than 2.1 mm between both shoulder joints may reflect dysfunction of rotator cuff muscles.

  5. Structural linear measurements in the newborn brain: accuracy of cranial ultrasound compared to MRI

    International Nuclear Information System (INIS)

    Leijser, Lara M.; Srinivasan, Latha; Cowan, Frances M.; Rutherford, Mary A.; Counsell, Serena J.; Allsop, Joanna M.

    2007-01-01

    Structural size in the neonatal brain is of clinical importance. Cranial ultrasonography (cUS) is the primary method used for evaluating the neonatal brain and it is important to know whether linear measurements made using this technique are accurate. To compare linear measurements of different cerebral structures made from neonatal cUS and contemporaneous MRI. Preterm and term infants studies with cUS and MRI on the same day were studied. Linear measurements made using both techniques from many cerebral structures were compared using a paired t-test. A total of 44 sets of scans from 26 preterm and 8 term infants were assessed. Small but significant differences between the cUS and MRI measurements (P<0.05) were found for the ventricular index, the posterior horn depth of the lateral ventricle, the extracerebral space and interhemispheric fissure, and the cortex of the cingulate gyrus. No significant differences were found for any other measurements. Linear measurements from cUS are accurate for most neonatal cerebral structures. Significant differences compared to MRI were found for a few structures, but only for the cortex were the absolute differences marked and possibly of clinical importance. (orig.)

  6. General Ultrasound Imaging

    Medline Plus

    Full Text Available ... inserted into a man's rectum to view the prostate. Transvaginal ultrasound. The transducer is inserted into a ... Stenting Ultrasound-Guided Breast Biopsy Obstetric Ultrasound Ultrasound - Prostate Biopsies - Overview Images related to General Ultrasound Videos ...

  7. General Ultrasound Imaging

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    Full Text Available ... News Physician Resources Professions Site Index A-Z General Ultrasound Ultrasound imaging uses sound waves to produce ... the limitations of General Ultrasound Imaging? What is General Ultrasound Imaging? Ultrasound is safe and painless, and ...

  8. Evolution of contrast agents for ultrasound imaging and ultrasound-mediated drug delivery

    Directory of Open Access Journals (Sweden)

    Vera ePaefgen

    2015-09-01

    Full Text Available Ultrasound is one of the most frequently used diagnostic methods. It is a non-invasive, comparably inexpensive imaging method with a broad spectrum of applications, which can be increased even more by using bubbles as contrast agents. There are various different types of bubbles: filled with different gases, composed of soft- or hard-shell materials, and ranging in size from nano- to micrometers. These intravascular contrast agents enable functional analyses, e.g. to acquire organ perfusion in real-time. Molecular analyses are achieved by coupling specific ligands to the bubbles’ shell, which bind to marker molecules in the area of interest. Bubbles can also be loaded with or attached to drugs, peptides or genes and can be destroyed by ultrasound pulses to locally release the entrapped agent. Recent studies show that ultrasound contrast agents are also valuable tools in hyperthermia-induced ablation therapy of tumors, or can increase cellular uptake of locally released drugs by enhancing membrane permeability. This review summarizes important steps in the development of ultrasound contrast agents and introduces the current clinical applications of contrast-enhanced ultrasound. Additionally, an overview of the recent developments in ultrasound probe design for functional and molecular diagnosis as well as for drug delivery is given.

  9. Color Doppler imaging and measurements of intraovarian and intrauterine vascularization on basal ultrasound examination in spontaneous ovulatory and anovulatory cycles

    Directory of Open Access Journals (Sweden)

    Kutlešić Ranko

    2008-01-01

    Full Text Available Background/Aim. Any organs functioning directly depends on vascularization. It applies also to the uterus and ovary which go through changes of vascularization during a menstruation cycle. The aim of this investigation was to determine differences in intrauterine and ovarian stromal arterioral blood flow on basal ultrasound examination (day 2-4 between spontaneous ovulatory and anovulatory cycles. Methods. This prospective clinical investigation included 205 patients divided into two groups: with ovulatory and with anovulatory cycles. Results. Resistance to ovarian arterioral stromal blood flow was significantly lower in the patients with ovulatory cycles (pulsatile index - PI 0.97 ± 0.4 vs 1.93 ± 1.37; p = 0.001737; and (resistance index - RI 0.55 ± 0.12 vs 0.68 ± 0.14; p = 0.040033. There were no statistically significant differences in arcuate arterioral blood flow in the pateints with ovulatory and anovulatory cycles (PI 1.21 ± 0.34 vs 61 ± 0,61 p = 0.136161 and RI 0.64 ± 0.11 vs 0.74 ± 0.07; p = 0.136649. The patients with ovulatory cycles had lower uterine radial arterioral blood flow than the patients with anovulatory cycles (PI 1.001 ± 0.22 vs 1.61 ± 0.23 p = 0.007501 and RI 0.55 ± 0.08 vs 0.71 ± 0.12; p = 0,0460113. The patients with ovulatory cycles had lower subendometrial arterioral blood flow resistance (PI 0.69 ± 0.19 vs 1.385±0.09; p = 0.00622 and RI 0.44 ± 0.09 vs 0.65 ± 0.02; p = 0.027458. Conclusion. Color Doppler ultrasuond imaging and measurements of intrauterine and ovarian stromal arterioral blood flow on basal ultrasound examination (day 2-4, showed lower resistance to blood flow in ovulatory than in anovulatory cycles.

  10. Local velocity measurements in lead-bismuth and sodium flows using the ultrasound doppler velocimetry

    International Nuclear Information System (INIS)

    Eckert, S.; Gerbeth, G.

    2003-01-01

    We will present measurements of the velocity profiles in liquid sodium and eutectic lead-bismuth by means of the Ultrasonic Doppler Velocimetry (UDV). A sodium flow in a rectangular duct exposed to an external, transverse magnetic field has been examined. To demonstrate the capability of UDV the transformation of the well-known turbulent, piston-like profile to an M-shaped velocity profile for growing magnetic field strength was observed. The significance of artifacts such as caused by the existence of reflecting interfaces in the measuring domain will be discussed. In the sodium case, the measurements were performed through the channel wall. An integrated ultrasonic sensor with acoustic wave-guide has been developed to overcome the limitation of ultrasonic transducers to temperatures lower than 200 .deg. C. This sensor can presently be applied at maximum temperatures up to 800 .deg. C. Stable and robust measurements have been performed in various PbBi flows in our laboratory at FZR as well as at the THESYS loop of the KALLA laboratory of the ForschungsZentrum Karlsruhe (FZK). We will also present experimental results obtained in a PbBi bubbly flow at 250...300 .deg. C. Argon bubbles were injected through a single orifice in a cylindrical container filled with stagnant PbBi. Velocity profiles were measured in the bubble plume. Mean values of the liquid as well as the bubble velocity were extracted from the data and will be presented as function of the gas flow rate

  11. Using ultrasound measurements of rump fat to assess nutritional condition of woodland caribou in northern British Columbia, Canada

    Directory of Open Access Journals (Sweden)

    David D. Gustine

    2007-04-01

    Full Text Available Body reserves (fat and protein of cervids are important to the reproductive success of individuals, and therefore may limit productivity of populations. We used a portable ultrasound machine to measure thickness of rump fat for 39 woodland caribou (Rangifer tarandus caribou captured in the winters (January–February of 2003 and 2004. We compared thickness of rump fat between pregnant and non-pregnant individuals in the Besa-Prophet drainage of northern British Columbia, Canada. Thirty-eight of the 39 females captured in British Columbia were adults and 34 of the adult caribou were pregnant (89.5 ± 5.1%, x– ± binomial SE. Pregnant individuals had more rump fat (0.60 ± 0.067 cm than nonpregnant animals (0.20 ± 0.029 cm. Recognizing that deposition and mobilization of fat vary with age and possibly across the winter season, ultrasonography can be used as a non-invasive technique in the field to assist in estimating body fat of caribou.

  12. Newer techniques for intravascular and intraoperative neurointerventional procedures

    International Nuclear Information System (INIS)

    Higashida, R.T.; Halbach, V.V.; Hieshima, G.B.; Yang, P.

    1987-01-01

    A videotape demonstrating newer techniques used in intravascular and intraoperative embolization procedures will be presented. The authors discuss the use of some of the newer embolic agents, real-time digital subtraction angiography, roadmapping techniques, and the use of microcatheters and steerable micro guide wires, which has greatly facilitated neurovascullar embolization procedures and enhanced patient safety. A number of actual intraoperative and intravascular cases will be shown demonstrating treatment of vascular malformations of the brain and spinal cord, carotid cavernous sinus fistulas, aneurysms and dural arteriovenous malformations. The indications for treatment, patient selection, technical preparation and newer methodologies and approaches to complex vascular lesions of the brain and spinal cord are discussed in detail

  13. Intravascular brachytherapy: a model for the calculation of the dose

    International Nuclear Information System (INIS)

    Pirchio, Rosana; Martin, Gabriela; Rivera, Elena; Cricco, Graciela; Cocca, Claudia; Gutierrez, Alicia; Nunez, Mariel; Bergoc, Rosa; Guzman, Luis; Belardi, Diego

    2002-01-01

    In this study we present the radiation dose distribution for a theoretical model with Montecarlo simulation, and based on an experimental model developed for the study of the prevention of restenosis post-angioplasty employing intravascular brachytherapy. In the experimental in vivo model, the atherosclerotic plaques were induced in femoral arteries of male New Zealand rabbits through surgical intervention and later administration of cholesterol enriched diet. For the intravascular irradiation we employed a 32P source contained within the balloon used for the angioplasty. The radiation dose distributions were calculated using the Monte Carlo code MCNP4B according to a segment of a simulated artery. We studied the radiation dose distribution in the axial and radial directions for different thickness of the atherosclerotic plaques. The results will be correlated with the biologic effects observed by means of histological analysis of the irradiated arteries (Au)

  14. Using the ultrasound and instrumented indentation techniques to measure the elastic modulus of engineering materials

    International Nuclear Information System (INIS)

    Meza, J. M.; Franco, E. E.; Farias, M. C. M.; Buiochi, F.; Souza, R. M.; Cruz, J.

    2008-01-01

    Currently, the acoustic and nano indentation techniques are two of the most used techniques for materials elastic modulus measurement. In this article fundamental principles and limitations of both techniques are shown and discussed. Last advances in nano indentation technique are also reviewed. an experimental study in ceramic, metallic, composite and single crystals was also done. Results shown that ultrasonic technique is capable to provide results in agreement with those reported in literature. However, ultrasonic technique does not allow measuring the elastic modulus of some small samples and single crystals. On the other hand, the nano indentation technique estimates the elastic modulus values in reasonable agreement with those measured by acoustic methods, particularly in amorphous materials, while in some policristaline materials some deviation from expected values was obtained. (Author) 29 refs

  15. Reproducibility of 3-Dimensional Ultrasound Measurements of Placental Volume at Gestational Ages 11 - 14 Weeks

    DEFF Research Database (Denmark)

    Larsen, M L; Naver, K V; Kjaer, M M

    2015-01-01

    .918 (0.812 - 0.966) and 0.983 (0.960- 0.993), LOA = [-22.9- 22.5] and [-14.3 - 12.1]), but interobserver reproducibility showed a wide range of agreement (LOA = [-50.5- 34.8]), particularly in cases with u-shaped placentas. CONCLUSION: The low interobserver reproducibility of VOCAL measurements...

  16. Reproducibility of 3-Dimensional Ultrasound Measurements of Placental Volume at Gestational Ages 11 - 14 Weeks

    DEFF Research Database (Denmark)

    Larsen, M L; Naver, K V; Kjaer, M M

    2016-01-01

    .918 (0.812 - 0.966) and 0.983 (0.960- 0.993), LOA = [-22.9- 22.5] and [-14.3 - 12.1]), but interobserver reproducibility showed a wide range of agreement (LOA = [-50.5- 34.8]), particularly in cases with u-shaped placentas. CONCLUSION: The low interobserver reproducibility of VOCAL measurements...

  17. Identification of ultrasound-contrast-agent dilution systems for ejection fraction measurements

    NARCIS (Netherlands)

    Mischi, M.; Jansen, A.H.M.; Kalker, A.A.C.M.; Korsten, H.H.M.

    2005-01-01

    Left ventricular ejection fraction is an important cardiac-efficiency measure. Standard estimations are based on geometric analysis and modeling; they require time and experienced cardiologists. Alternative methods make use of indicator dilutions, but they are invasive due to the need for

  18. CALF BLOOD-FLOW AND POSTURE - DOPPLER ULTRASOUND MEASUREMENTS DURING AND AFTER EXERCISE

    NARCIS (Netherlands)

    VANLEEUWEN, BE; BARENDSEN, GJ; LUBBERS, J; DEPATER, L

    To investigate the joint effects of body posture and calf muscle pump, the calf blood flow of eight healthy volunteers was measured with pulsed Doppler equipment during and after 3 min of rhythmic exercise on a calf ergometer in the supine, sitting, and standing postures. Muscle contractions

  19. Prostate Ultrasound

    Medline Plus

    Full Text Available ... be able to give a clearer picture of soft tissues that do not show up well on x-ray images. Ultrasound causes no health problems and may be repeated as often as is necessary if medically indicated. Ultrasound provides real-time imaging, making it a good tool for guiding ...

  20. Prostate Ultrasound

    Science.gov (United States)

    ... be able to give a clearer picture of soft tissues that do not show up well on x-ray images. Ultrasound causes no health problems and may be repeated as often as is necessary if medically indicated. Ultrasound provides real-time imaging, making it a good tool for guiding ...

  1. Ultrasound -- Pelvis

    Medline Plus

    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z Ultrasound - Pelvis Ultrasound imaging of the pelvis uses sound waves to ...

  2. Interventional ultrasound

    International Nuclear Information System (INIS)

    VanSonnenberg, E.

    1987-01-01

    This book contains 12 chapters and several case studies. Some of the chapter titles are: The Interplay of Ultrasound and Computed Tomography in the Planning and Execution of Interventional Procedures: Ulltrasound Guided Biopsy; Interventioal Genitourinary Sonography; Diagnosis and Treatment of Pericardial Effusion Using Ultrasonic Guidance; and New Ultrasound-Guided Interventional Procedures--Cholecystostomy, Pancreatography, Gastrostomy

  3. Ultrasound -- Pelvis

    Medline Plus

    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z Ultrasound - Pelvis Ultrasound imaging ...

  4. Prostate Ultrasound

    Medline Plus

    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z Ultrasound - Prostate Ultrasound of ...

  5. Ultrasound stethoscopy

    NARCIS (Netherlands)

    E.C. Vourvouri (Eleni)

    2002-01-01

    textabstractIn this thesis we repmi the many evaluation studies with the hand-held ultrasound device in the assessment of different cardiac pathologies and in different clinical settings. The reason for using the tetm "ultrasound stethoscopy" is that these devices are augmenting our

  6. Ultrasound -- Pelvis

    Medline Plus

    Full Text Available ... to-use and less expensive than other imaging methods. Ultrasound imaging is extremely safe and does not use any ionizing radiation. Ultrasound scanning gives a clear picture of soft tissues that do not show up well on ...

  7. Prostate Ultrasound

    Medline Plus

    Full Text Available ... the best way to see if treatment is working or if a finding is stable or changed over time. top of page What are the benefits vs. risks? Benefits Ultrasound is widely available, easy-to-use and less expensive than other imaging methods. Ultrasound imaging uses ...

  8. Prostate Ultrasound

    Medline Plus

    Full Text Available ... the patient. Because ultrasound images are captured in real-time, they can show the structure and movement of ... blood test result. difficulty urinating. Because ultrasound provides real-time images, it also can be used to guide ...

  9. Asian-variant intravascular lymphoma in the African race

    Directory of Open Access Journals (Sweden)

    Holly Geyer

    2012-03-01

    Full Text Available Intravascular large B-cell lymphoma (IVLBCL is an exceptionally rare form of non- Hodgkin lymphoma (NHL distinguished by the preferential growth of neoplastic cells within blood vessel lumen. Challenging to detect and deemed disseminated at diagnosis, this condition is characterized by a highly aggressive, inconspicuous course with a high mortality rate. We describe the case of a 48 year-old African-American female presenting with a two month history of low-grade fevers and malaise. Laboratory data was notable for anemia, thrombocytopenia, elevated liver function tests, and hematuria. An extensive workup for infectious, rheumatologic and malignant causes was negative. Her symptoms progressed and within two weeks, she was admitted for disseminated intravascular coagulation (DIC. Her course was complicated by diffuse pulmonary hemorrhage and ultimately, care was withdrawn. Autopsy identified widespread CD-20 positive intravascular large B-cell lymphoma with significant hepatosplenic involvement, characteristic of the Asian variant IVLBCL. This case uniquely highlights development of the Asian variant IVLBVL in a previously undescribed race. Identified by its intraluminal vascular growth pattern, IVLBCL generally spares lymphatic channels. Diagnosis and differentiation of this condition from other hematological malignancies via skin, visceral and bone marrow biopsy is imperative as anthracycline-containing chemotherapies may significantly improve clinical outcomes. This article outlines the common presentation, natural course, and treatment options of IVLBCL, along with the histopathology, immunohistochemistry, and chromosomal aberrations common to this condition.

  10. Local release of ATP into the arterial inflow and venous drainage of human skeletal muscle: insight from ATP determination with the intravascular microdialysis technique

    DEFF Research Database (Denmark)

    Mortensen, Stefan; Thaning, Pia; Nyberg, Michael Permin

    2011-01-01

    is released into plasma, we measured plasma [ATP] with the intravascular microdialysis technique at rest and during dynamic exercise (normoxia and hypoxia), passive exercise, thigh compressions and arterial ATP, tyramine and ACh infusion in a total of 16 healthy young men. Femoral arterial and venous...

  11. Low-temperature elastic properties of YbSbPt probed by ultrasound measurements

    Science.gov (United States)

    Nakanishi, Y.; Takahashi, S.; Ohyama, R.; Hasegawa, J.; Nakamura, M.; Suzuki, H.; Yoshizawa, M.

    2018-03-01

    The elastic properties of a single crystal of the half-Heusler compound YbSbPt have been investigated by means of the ultrasonic measurement. In particular, careful measurements of the temperature (T) dependent elastic constant C 11(T) was performed in the vicinity of its phase transition point near T N of 0.5 K. A clear step-like anomaly accompanied by spin-density-wave type antiferromagnetic (AFM) phase transition was found in the C 11(T) curve. The low-temperature magnetic phase diagram is proposed on the basis of the results. The phase diagram consists of, at least two main distinct phases: a low-field and high-field regime with a transition field of approximately 0.6 T at zero field. We discuss the low-temperature elastic property based on analysis of Landau-type free energy.

  12. Development of Ultrasound to Measure In-vivo Dynamic Cervical Spine Intervertebral Disc Mechanics

    Science.gov (United States)

    2014-01-01

    The deformation between C4 and C6 measured by the US probe was affected by bulging of the IVD and soft tissues during compressive loading as...endplates of the vertebrae and cartilaginous endplate of the discs were added to all segments. Figure 28 Coronal views of the updated C4-T1 FEM (a...the ligaments and soft tissue connections that provide stability to the cervical spine FSUs were added (Figures 30 and 31). For the anterior

  13. Measurements of the weak bonding interfacial stiffness by using air-coupled ultrasound

    Directory of Open Access Journals (Sweden)

    Wen-Lin Wu

    2017-12-01

    Full Text Available An air-coupled ultrasonic method, focusing on the problem that weak bonding interface is difficult to accurately measure using conventional nondestructive testing technique, is proposed to evaluate the bond integrity. Based on the spring model and the potential function theory, a theoretical model is established to predict the through-transmission spectrum in double-layer adhesive structure. The result of a theoretical algorithm shows that all the resonant transmission peaks move towards higher frequency with the increase of the interfacial stiffness. The reason for these movements is related to either the normal stiffness (KN or the transverse stiffness (KT. A method to optimize the measurement parameters (i.e. the incident angle and testing frequency is put forward through analyzing the relationship between the resonant transmission peaks and the interfacial spring stiffness at the frequency below 1MHz. The air-coupled ultrasonic testing experiments at the normal and oblique incident angle respectively are carried out to verify the theoretical analysis and to accurately measure the interfacial stiffness of double-layer adhesive composite plate. The experimental results are good agreement with the results from the theoretical algorithm, and the relationship between bonding time and interfacial stiffness is presented at the end of this paper.

  14. Inter-Scan Reproducibility of Carotid Plaque Volume Measurements by 3-D Ultrasound

    DEFF Research Database (Denmark)

    Sandholt, Benjamin V; Collet-Billon, Antoine; Entrekin, Robert

    2018-01-01

    (PPV) measure centered on MPT. Total plaque volume (TPV), PPV from a 10-mm segment and MPT were measured using dedicated semi-automated software on 38 plaques from 26 patients. Inter-scan reproducibility was assessed using the t-test, Bland-Altman plots and Pearson's correlation coefficient....... There was a mean difference of 0.01 mm in MPT (limits of agreement: -0.45 to 0.42 mm, Pearson's correlation coefficient: 0.96). Both volume measurements exhibited high reproducibility, with PPV being superior (limits of agreement: -35.3 mm3to 33.5 mm3, Pearson's correlation coefficient: 0.96) to TPV (limits...... of agreement: -88.2 to 61.5 mm3, Pearson's correlation coefficient: 0.91). The good reproducibility revealed by the present results encourages future studies on establishing plaque quantification as part of cardiovascular risk assessment and for follow-up of disease progression over time....

  15. Validating Intravascular Imaging with Serial Optical Coherence Tomography and Confocal Fluorescence Microscopy.

    Science.gov (United States)

    Tardif, Pier-Luc; Bertrand, Marie-Jeanne; Abran, Maxime; Castonguay, Alexandre; Lefebvre, Joël; Stähli, Barbara E; Merlet, Nolwenn; Mihalache-Avram, Teodora; Geoffroy, Pascale; Mecteau, Mélanie; Busseuil, David; Ni, Feng; Abulrob, Abedelnasser; Rhéaume, Éric; L'Allier, Philippe; Tardif, Jean-Claude; Lesage, Frédéric

    2016-12-15

    Atherosclerotic cardiovascular diseases are characterized by the formation of a plaque in the arterial wall. Intravascular ultrasound (IVUS) provides high-resolution images allowing delineation of atherosclerotic plaques. When combined with near infrared fluorescence (NIRF), the plaque can also be studied at a molecular level with a large variety of biomarkers. In this work, we present a system enabling automated volumetric histology imaging of excised aortas that can spatially correlate results with combined IVUS/NIRF imaging of lipid-rich atheroma in cholesterol-fed rabbits. Pullbacks in the rabbit aortas were performed with a dual modality IVUS/NIRF catheter developed by our group. Ex vivo three-dimensional (3D) histology was performed combining optical coherence tomography (OCT) and confocal fluorescence microscopy, providing high-resolution anatomical and molecular information, respectively, to validate in vivo findings. The microscope was combined with a serial slicer allowing for the imaging of the whole vessel automatically. Colocalization of in vivo and ex vivo results is demonstrated. Slices can then be recovered to be tested in conventional histology.

  16. Ultrasound Characterization of Microbead and Cell Suspensions by Speed of Sound Measurements of Neutrally Buoyant Samples

    DEFF Research Database (Denmark)

    Cushing, Kevin W.; Garofalo, Fabio; Magnusson, Cecilia

    2017-01-01

    . The density of the microparticles is determined by using a neutrally buoyant selection process that involves centrifuging of microparticles suspended in different density solutions, CsCl for microbeads and Percoll for cells. The speed of sound at 3 MHz in the neutrally buoyant suspensions is measured...... and fixed cells, such as red blood cells, white blood cells, DU-145 prostate cancer cells, MCF-7 breast cancer cells, and LU-HNSCC-25 head and-neck squamous carcinoma cells in phosphate buffered saline. The results show agreement with published data obtained by other methods....

  17. Intrauterine intravascular transfusion for fetal haemolytic anaemia: the Western Australian experience.

    Science.gov (United States)

    Newnham, J P; Phillips, J M; Stock, R

    1992-11-16

    To report the first four years' clinical experience with fetal intravascular blood transfusion for the treatment of fetal haemolytic anaemia in Western Australia. King Edward Memorial Hospital, Perth, which is the sole tertiary level perinatal centre in Western Australia with a referral base of approximately 25,000 pregnancies each year. Transfusion was by injection of packed cells from Rh-negative donors into the fetal umbilical vein near the site of insertion into the placenta. Fetal haemoglobin levels were measured before and after each transfusion. In most cases, the fetus was paralysed by intramuscular tubocurarine. Sixty intravenous transfusions were performed in 20 pregnancies. At the time of the initial transfusion, the mean haemoglobin level was 5.8 g/dL (range, 2.5-8.5 g/dL) and six fetuses had signs of hydrops. The case survival rate was 80% and the procedure survival rate was 93%. Three of the deaths occurred in the first five cases. Caesarean section was performed during two of the procedures, one because of bleeding from the cord puncture site and one because of tamponade of the umbilical vessels. Fetal intravascular transfusion is a highly effective treatment for fetal alloimmunisation and allows pregnancies to continue to term and to be delivered vaginally. However, the procedure may be difficult and requires a team approach with ready access to fetal monitoring and emergency caesarean section. Our results suggest that increasing experience of the team is a major factor in improved outcome.

  18. Non-invasive treatment efficacy evaluation for high-intensity focused ultrasound therapy using magnetically induced magnetoacoustic measurement

    Science.gov (United States)

    Guo, Gepu; Wang, Jiawei; Ma, Qingyu; Tu, Juan; Zhang, Dong

    2018-04-01

    Although the application of high intensity focused ultrasound (HIFU) has been demonstrated to be a non-invasive treatment technology for tumor therapy, the real-time temperature monitoring is still a key issue in the practical application. Based on the temperature-impedance relation, a fixed-point magnetically induced magnetoacoustic measurement technology of treatment efficacy evaluation for tissue thermocoagulation during HIFU therapy is developed with a sensitive indicator of critical temperature monitoring in this study. With the acoustic excitation of a focused transducer in the magnetoacoustic tomography with the magnetic induction system, the distributions of acoustic pressure, temperature, electrical conductivity, and acoustic source strength in the focal region are simulated, and the treatment time dependences of the peak amplitude and the corresponding amplitude derivative under various acoustic powers are also achieved. It is proved that the strength peak of acoustic sources is generated by tissue thermocoagulation with a sharp conductivity variation. The peak amplitude of the transducer collected magnetoacoustic signal increases accordingly along with the increase in the treatment time under a fixed acoustic power. When the temperature in the range with the radial and axial widths of about ±0.46 mm and ±2.2 mm reaches 69 °C, an obvious peak of the amplitude derivative can be achieved and used as a sensitive indicator of the critical status of treatment efficacy. The favorable results prove the feasibility of real-time non-invasive temperature monitoring and treatment efficacy evaluation for HIFU ablation using the magnetically induced magnetoacoustic measurement, and might provide a new strategy for accurate dose control during HIFU therapy.

  19. Measurement of misalignment in a journal bearing with low frequency ultrasound

    International Nuclear Information System (INIS)

    Kim, Noh Nu

    1998-01-01

    Misalignment of a shaft in journal bearing of rotary compressor was measured and analyzed for the study on the effect of misalignment on the performance of the rotary compressor using a new ultrasonic pulse-echo technique. Two low-frequency ultrasonic transducers(10Mhz) were mounted on the outer surface of the bearing in X and Y axis to receive the reflection signals from each axis and to obtain the amplitude of a modified reflection wave defined as the total reflection wave minus the first reflection wave from a thin layer which is inversely proportional to the thickness of the layer in the region where h/λ is approximately less than 1/4. The relationship of the amplitude of the modified reflection wave to the thickness of the oil layer was shown both in mathematical form and in graph. Gap clearances between the bearing and the shaft in the horizontal and vertical axis were determined directly by the relationship and used to evaluate the misalignment of the journal bearing. Several intentional misalignments in a test compressor were made to measure and show the misalignment and the effect of the misalignment on the efficiency of the rotary compressor. A fast quantitative evaluation of the misalignment of journal bearing was possible using the amplitude of the modified reflection signal without any inversion process to extract thickness information from waveforms of the reflected waves.

  20. Ultrasound pulse-echo measurements on rough surfaces with linear array transducers

    DEFF Research Database (Denmark)

    Sjøj, Sidsel M. N.; Blanco, Esther N.; Wilhjelm, Jens E.

    2012-01-01

    The echo from planar surfaces with rms roughness, Rq, in the range from 0-155 μm was measured with a clinical linear array transducer at different angles of incidence at 6 MHz and 12 MHz. The echo-pulse from the surfaces was isolated with an equal sized window and the power of the echo-pulse was ......The echo from planar surfaces with rms roughness, Rq, in the range from 0-155 μm was measured with a clinical linear array transducer at different angles of incidence at 6 MHz and 12 MHz. The echo-pulse from the surfaces was isolated with an equal sized window and the power of the echo......-pulse was calculated. The power of the echo from the smooth surface (Rq = 0) is highly angle-dependent due to a high degree of specular reflection. Within the angular range considered here, -10° to 10°, the variation spans a range of 18 dB at both 6 MHz and 12 MHz. When roughness increases, the angle......-dependence decreases, as the echo process gradually changes from pure reflection to being predominantly governed by backscattering. The power of the echoes from the two roughest surfaces (Rq = 115 μm and 155 μm) are largely independent of angle at both 6 MHz and 12 MHz with a variation of 2 dB in the angular range...

  1. Thickness Measurement of a Film on a Substrate by Low-Frequency Ultrasound

    Institute of Scientific and Technical Information of China (English)

    LI Ming-Xuan; WANG Xiao-Min; MAO Jie

    2004-01-01

    @@ We describe a new simple technique for the low-frequency ultrasonic thickness measurement of an air-backed soft thin layer attached on a hard substrate of finite thickness through the frequency-shifts of the substrate resonances by the substrate-side insonification. A plane compressive wave impinging normally on the substrate surface from a liquid is studied. Low frequency here means an interrogating acoustical wave frequency of less than half of coating to the substrate. Equations for the frequency-shifts are derived and solved by the Newton iterative method and the Taylor expansion method, respectively, indicating satisfactory agreement within the range of interest of thickness ratio of the thin layer to the substrate for a polymer-aluminium structure. An experimental setup is constructed to verify the validity of the technique.

  2. Bone mineral density changes during pregnancy in actively exercising women as measured by quantitative ultrasound.

    Science.gov (United States)

    To, William W K; Wong, Margaret W N

    2012-08-01

    To evaluate whether bone mineral density (BMD) changes in women engaged in active exercises during pregnancy would be different from non-exercising women. Consecutive patients with singleton pregnancies who were engaged in active exercise training during pregnancy were prospectively recruited over a period of 6 months. Quantitative USG measurements of the os calcis BMD were performed at 14-20 weeks and at 36-38 weeks. These patients were compared to a control cohort of non-exercising low-risk women. A total of 24 physically active women undergoing active physical training of over 10 h per week at 20 weeks gestation and beyond (mean 13.1 h, SD 3.3) were compared to 94 non-exercising low-risk women. A marginal fall in BMD of 0.015 g/cm(2) (SD 0.034) was demonstrable from early to late gestation in the exercising women, which was significantly lower than that of non-exercising women (0.041 g/cm(2); SD 0.042; p = 0.005). Logistic regression models confirmed that active exercises in pregnancy were significantly associated with the absence of or less BMD loss in pregnancy. In women actively engaged in physical training during pregnancy, the physiological fall in BMD during pregnancy was apparently less compared to those who did not regularly exercise.

  3. High-frequency ultrasound measurements of the normal ciliary body and iris.

    Science.gov (United States)

    Garcia, Julian P S; Spielberg, Leigh; Finger, Paul T

    2011-01-01

    To determine the normal ultrasonographic thickness of the iris and ciliary body. This prospective 35-MHz ultrasonographic study included 80 normal eyes of 40 healthy volunteers. The images were obtained at the 12-, 3-, 6-, and 9-o'clock radial meridians, measured at three locations along the radial length of the iris and at the thickest section of the ciliary body. Mixed model was used to estimate eye site-adjusted means and standard errors and to test the statistical difference of adjusted results. Parameters included mean thickness, standard deviation, and range. Mean thicknesses at the iris root, midway along the radial length of the iris, and at the juxtapupillary margin were 0.4 ± 0.1, 0.5 ± 0.1, and 0.6 ± 0.1 mm, respectively. Those of the ciliary body, ciliary processes, and ciliary body + ciliary processes were 0.7 ± 0.1, 0.6 ± 0.1, and 1.3 ± 0.2 mm, respectively. This study provides standard, normative thickness data for the iris and ciliary body in healthy adults using ultrasonographic imaging. Copyright 2011, SLACK Incorporated.

  4. Application of Gafchromic registered film in the dosimetry of an intravascular brachytherapy source

    International Nuclear Information System (INIS)

    Song Haijun; Roa, D. Eduardo; Yue Ning; D'Errico, Francesco; Chen Zhe; Nath, Ravinder

    2006-01-01

    The methodology of brachytherapy source dosimetry with Gafchromic registered MD 55-2 film (ISP Technologies, Inc.) is examined with an emphasis on the nonlinearity of the optical density-dose relation within the dynamic dose range, the radial distance-dependent measurement uncertainty, and the format of data presentation. The specific source chosen for this study was a Checkmate trade mark sign (Cordis Corporation) intravascular brachytherapy system. The two-dimensional dose distribution around the source was characterized by a comprehensive analysis of measurement uncertainties. A comparative analysis of the dosimetric data from the vendor and from the scientific literature showed a substantial consistency of the information available for the Checkmate trade mark sign source. Our two-dimensional dosimetric data for the Checkmate trade mark sign source trains is presented in the form of measured along and away dose tables

  5. Measurement of the elastic tensor of SmScO3 and NdScO3 using resonant ultrasound spectroscopy with ab initio calculations

    Directory of Open Access Journals (Sweden)

    K. A. Pestka II

    2011-09-01

    Full Text Available The complete elastic tensors of SmScO3 and NdScO3 were measured using resonant ultrasound spectroscopy (RUS in combination with ab-initio calculations. Measurement of the elastic tensor of these recently synthesized single crystal RE scandates is essential for understanding dynamic lattice applications including phonon confinement, strain induced thin film growth and superlattice construction. On average, the experimental elastic constants differed by less than 5% of the theoretical values, further validating the accuracy of modern ab-initio calculations as a means of estimating the initial elastic constants used in RUS measurements.

  6. Pharmacokinetic changes induced by focused ultrasound in glioma-bearing rats as measured by dynamic contrast-enhanced MRI.

    Directory of Open Access Journals (Sweden)

    Feng-Yi Yang

    Full Text Available Focused ultrasound (FUS combined with microbubbles has been shown to be a noninvasive and targeted drug delivery technique for brain tumor treatment. The purpose of this study was to measure the kinetics of Gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA in glioma-bearing rats in the presence of FUS-induced blood-brain barrier disruption (BBB-D by magnetic resonance imaging (MRI. A total of ten glioma-bearing rats (9-12 weeks, 290-340 g were used in this study. Using dynamic contrast-enhanced (DCE-MRI, the spatial permeability of FUS-induced BBB-D was evaluated and the kinetic parameters were calculated by a general kinetic model (GKM. The results demonstrate that the mean Ktrans of the sonicated tumor (0.128±0.019 at 20 min and 0.103±0.023 at 24 h after sonication, respectively was significantly higher than (2.46-fold at 20 min and 1.78-fold at 24 h that of the contralateral (non-sonicated tumor (0.052±0.019 at 20 min and 0.058±0.012 at 24 h after sonication, respectively. In addition, the transfer constant Ktrans in the sonicated tumor correlated strongly with tissue EB extravasation (R = 0.95, which suggests that DCE-MRI may reflect drug accumulation in the brain. Histological observations showed no macroscopic damage except for a few small erythrocyte extravasations. The current study demonstrates that DCE-MRI can monitor the dynamics of the FUS-induced BBB-D process and constitutes a useful tool for quantifying BBB permeability in tumors.

  7. Long-term safety and feasibility of three-vessel multimodality intravascular imaging in patients with ST-elevation myocardial infarction

    DEFF Research Database (Denmark)

    Taniwaki, Masanori; Radu, Maria D; Garcia-Garcia, Hector M

    2015-01-01

    We assessed the feasibility and the procedural and long-term safety of intracoronary (i.c) imaging for documentary purposes with optical coherence tomography (OCT) and intravascular ultrasound (IVUS) in patients with acute ST-elevation myocardial infarction (STEMI) undergoing primary PCI in the s......We assessed the feasibility and the procedural and long-term safety of intracoronary (i.c) imaging for documentary purposes with optical coherence tomography (OCT) and intravascular ultrasound (IVUS) in patients with acute ST-elevation myocardial infarction (STEMI) undergoing primary PCI...... in the setting of IBIS-4 study. IBIS4 (NCT00962416) is a prospective cohort study conducted at five European centers including 103 STEMI patients who underwent serial three-vessel coronary imaging during primary PCI and at 13 months. The feasibility parameter was successful imaging, defined as the number...... of pullbacks suitable for analysis. Safety parameters included the frequency of peri-procedural complications, and major adverse cardiac events (MACE), a composite of cardiac death, myocardial infarction (MI) and any clinically-indicated revascularization at 2 years. Clinical outcomes were compared...

  8. Muscle thickness and muscle quality measured by ultrasound: influence of different sites of measurement DOI: 10.5007/1980-0037.2011v13n2p87

    Directory of Open Access Journals (Sweden)

    Ronei Silveira Pinto

    2011-03-01

    Full Text Available The aims of this study were: a to investigate differences in muscle thickness (MT measured by ultrasound and muscle quality (MQ at three sites in the elbow flexors and knee extensors, and b to correlate MT with isometric force production of the elbow flexors and knee extensors. Sixty-nine young male subjects participated in this study. The isometric force production values of the elbow flexors and knee extensors were obtained at 90° and 60°, respectively. MT was assessed at three sites in the elbow flexors (proximal – BB1, middle – BB2, and distal – BB3 and knee extensors (proximal – RI1, middle – RI2, and distal – RI3. Differences between the three measurements of MT and MQ were evaluated by one-way repeated measures ANOVA. Pearson’s correlation test was used to assess the correlation between MT and isometric force. The level of significance was set at p<0.05. The results showed significant differences (p<0.001 between the three MT and MQ sites in the elbow flexors (BB1, BB2, BB3 and in the knee extensors (RI1, RI2, RI3. The correlation between BB1, BB2 and BB3 and force production was r=0.57, r=0.52 and r=0.59, respectively (p<0.05. In the knee extensors, the correlation between RI1, RI2 and RI3 and force production was r=0.47, r=0.51 and r=0.53, respectively (p<0.01. There were significant differences in MQ between elbow flexors (p<0.001 and knee extensors (p<0.001. The present results showed that the site of measurement has a significant influence on MT and MQ. Furthermore, MT was positively correlated with isometric force production in the elbow flexors and knee extensors.

  9. Relationship between feed intake, feeding behaviors, performance, and ultrasound carcass measurements in growing purebred Angus and Hereford bulls.

    Science.gov (United States)

    Kayser, W; Hill, R A

    2013-11-01

    The objectives of this study were to examine the growth, DMI, and feeding behaviors of Angus and Hereford bulls; identify the relationships between feeding behaviors and variation in DMI and residual feed intake (RFI); and determine the value of feeding behaviors in predicting DMI. Individual DMI was measured in Angus bulls (n=189; initial BW=427±3.4 kg) and Hereford bulls (n=146; initial BW=411±4.1 kg) fed a grower ration for 71 d in 2009, 78 d in 2010, and 74 d in 2011 using a GrowSafe intake monitoring system. Feeding frequency (FF, meals/d), head down duration (HDD, s/d), head down duration per meal (HDDM, HDD/FF, s/meal), average meal size [AMS, kg/(meal·d)], and feeding rate (FR, g/s) were also measured or calculated using behavior data collected by the GrowSafe system. Ultrasound measures of 12th-rib fat thickness (UFT), longissimus muscle area (ULMA), and intramuscular fat (IMF) were determined during the midtest-weight event of every trial. The data from 3 yr were pooled to generate mean differences between the breeds. Residual feed intake was calculated using a linear regression of DMI on ADG and midtest BW0.75 (MMWT). Animals were classified into 3 RFI groups based on their RFI score as Low (>0.5 SD below the mean), Average (±0.5 SD from the mean), or High RFI (>0.5 SD above the mean). Angus bulls in the Low RFI group consumed 17% (PAngus and Hereford bulls, respectively. The HDD, HDDM, and FR were significantly correlated with DMI. The feeding behavior traits, HDD, HDDM, and FR when added to the RFI base model, explained 18, 17, and 13%, respectively, of the variation in DMI not explained by ADG and MMWT in Angus bulls. Similarly, in Hereford bulls, HDD, HDDM, and FR explained 35, 26, and 24%, respectively, of the variation in DMI not explained by ADG and MMWT. These data suggest that feeding behaviors are related to DMI of growing Angus and Hereford bulls.

  10. Fetal Ultrasound

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    ... isn't recommended simply to determine a baby's sex. Similarly, fetal ultrasound isn't recommended solely for the purpose of producing keepsake videos or pictures. If your health care provider doesn' ...

  11. Ultrasound -- Pelvis

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    Full Text Available ... and movement of the body's internal organs, as well as blood flowing through blood vessels. Ultrasound imaging is a noninvasive medical test that helps physicians diagnose and treat medical conditions. ...

  12. Prostate Ultrasound

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    Full Text Available ... and movement of the body's internal organs, as well as blood flowing through blood vessels. Ultrasound imaging is a noninvasive medical test that helps physicians diagnose and treat medical conditions. ...

  13. Prostate Ultrasound

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    Full Text Available ... nodule felt by a physician during a routine physical exam or prostate cancer screening exam. an elevated blood test result. difficulty urinating. Because ultrasound provides real-time ...

  14. Prostate Ultrasound

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    Full Text Available ... requested the exam. Usually, the referring physician or health care provider will share the results with you. ... well on x-ray images. Ultrasound causes no health problems and may be repeated as often as ...

  15. Ultrasound -- Pelvis

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    Full Text Available ... ultrasound exams are also used to monitor the health and development of an embryo or fetus during ... requested the exam. Usually, the referring physician or health care provider will share the results with you. ...

  16. Prostate Ultrasound

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    Full Text Available ... probe) and ultrasound gel placed directly on the skin. High-frequency sound waves are transmitted from the ... the transducer (the device placed on the patient's skin to send and receive the returning sound waves), ...

  17. Ultrasound -- Pelvis

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    Full Text Available ... probe) and ultrasound gel placed directly on the skin. High-frequency sound waves are transmitted from the ... the transducer (the device placed on the patient's skin to send and receive the returning sound waves), ...

  18. Prostate Ultrasound

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    Full Text Available ... no ionizing radiation. Ultrasound scanning may be able to give a clearer picture of soft tissues that do ... understanding of the possible charges you will incur. Web page review process: This Web page is reviewed ...

  19. Ultrasound -- Pelvis

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    Full Text Available ... use different transducers (with different capabilities) during a single exam. The transducer sends out high-frequency sound ... modality for the diagnosis and monitoring of pregnant women and their unborn babies. Ultrasound provides real-time ...

  20. Ultrasound -- Pelvis

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    Full Text Available ... collects the sounds that bounce back and a computer then uses those sound waves to create an ... Ultrasound scanners consist of a console containing a computer and electronics, a video display screen and a ...

  1. Prostate Ultrasound

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    Full Text Available ... collects the sounds that bounce back and a computer then uses those sound waves to create an ... Ultrasound scanners consist of a console containing a computer and electronics, a video display screen and a ...

  2. Prostate Ultrasound

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    Full Text Available ... sends out high-frequency sound waves (that the human ear cannot hear) into the body and then ... ultrasound , there are no known harmful effects on humans. top of page What are the limitations of ...

  3. Prostate Ultrasound

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    Full Text Available ... is located directly in front of the rectum, so the ultrasound exam is performed transrectally in order ... A follow-up examination may also be necessary so that any change in a known abnormality can ...

  4. Prostate Ultrasound

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    Full Text Available ... the rectal wall is relatively insensitive to the pain in the region of the prostate. A biopsy ... needle biopsies and fluid aspiration. Risks For standard diagnostic ultrasound , there are no known harmful effects on ...

  5. Prostate Ultrasound

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    Full Text Available ... diagnose symptoms such as difficulty urinating or an elevated blood test result. It’s also used to investigate ... physical exam or prostate cancer screening exam. an elevated blood test result. difficulty urinating. Because ultrasound provides ...

  6. Ultrasound -- Pelvis

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    Full Text Available ... The principles are similar to sonar used by boats and submarines. The ultrasound image is immediately visible ... principles involved in the sonar used by bats, ships and fishermen. When a sound wave strikes an ...

  7. Ultrasound -- Pelvis

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    Full Text Available ... areas of the body while other areas, especially air-filled lungs, are poorly suited for ultrasound. For ... make secure contact with the body and eliminate air pockets between the transducer and the skin that ...

  8. Prostate Ultrasound

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    Full Text Available ... a follow-up exam is done because a potential abnormality needs further evaluation with additional views or ... of soft tissues that do not show up well on x-ray images. Ultrasound causes no health ...

  9. Ultrasound -- Pelvis

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    Full Text Available ... a follow-up exam is done because a potential abnormality needs further evaluation with additional views or ... of soft tissues that do not show up well on x-ray images. Ultrasound is the preferred ...

  10. Ultrasound -- Pelvis

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    Full Text Available ... is smaller than the standard speculum used when performing a Pap test . A protective cover is placed ... of soft tissues that do not show up well on x-ray images. Ultrasound is the preferred ...

  11. Prostate Ultrasound

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    Full Text Available ... scanning or sonography , involves the use of a small transducer (probe) and ultrasound gel placed directly on ... to do the scanning. The transducer is a small hand-held device that resembles a microphone, attached ...

  12. Ultrasound -- Pelvis

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    Full Text Available ... scanning or sonography , involves the use of a small transducer (probe) and ultrasound gel placed directly on ... the child prior to the exam. Bringing books, small toys, music or games can help to distract ...

  13. Prostate Ultrasound

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    Full Text Available ... less than 20 minutes. top of page What will I experience during and after the procedure? Ultrasound ... in the region of the prostate. A biopsy will add time to the procedure. Rarely, a small ...

  14. Ultrasound -- Pelvis

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    Full Text Available ... ultrasound images are reviewed. top of page What will I experience during and after the procedure? For ... in the region of the prostate. A biopsy will add time to the procedure. If a Doppler ...

  15. Ultrasound -- Pelvis

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    Full Text Available ... arteries and veins in the abdomen, arms, legs, neck and/or brain (in infants and children) or ... diagnose symptoms experienced by women such as: pelvic pain abnormal vaginal bleeding other menstrual problems Ultrasound exams ...

  16. Prostate Ultrasound

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    Full Text Available ... gel. top of page How does the procedure work? Ultrasound imaging is based on the same principles ... the best way to see if treatment is working or if a finding is stable or changed ...

  17. Ultrasound -- Pelvis

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    Full Text Available ... and development of an embryo or fetus during pregnancy. See the Obstetrical Ultrasound page for more information . ... move through vessels. The movement of blood cells causes a change in pitch of the reflected sound ...

  18. Ultrasound -- Pelvis

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    Full Text Available ... abdomen, arms, legs, neck and/or brain (in infants and children) or within various body organs such ... and monitoring of pregnant women and their unborn babies. Ultrasound provides real-time imaging, making it a ...

  19. Ultrasound -- Pelvis

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    Full Text Available ... to-use and less expensive than other imaging methods. Ultrasound imaging is extremely safe and does not ... barium exams, CT scanning , and MRI are the methods of choice in such a setting. Large patients ...

  20. Ultrasound -- Pelvis

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    Full Text Available ... insertion. top of page How does the procedure work? Ultrasound imaging is based on the same principles ... move through vessels. The movement of blood cells causes a change in pitch of the reflected sound ...