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Sample records for contrast-enhanced ultrasound imaging

  1. Contrast enhanced ultrasound in liver imaging

    International Nuclear Information System (INIS)

    Nielsen, Michael Bachmann; Bang, Nanna

    2004-01-01

    Ultrasound contrast agents were originally introduced to enhance the Doppler signals when detecting vessels with low velocity flow or when imaging conditions were sub-optimal. Contrast agents showed additional properties, it was discovered that a parenchymal enhancement phase in the liver followed the enhancement of the blood pool. Contrast agents have made ultrasound scanning more accurate in detection and characterization of focal hepatic lesions and the sensitivity is now comparable with CT and MRI scanning. Further, analysis of the transit time of contrast agent through the liver seems to give information on possible hepatic involvement, not only from focal lesions but also from diffuse benign parenchymal disease. The first ultrasound contrast agents were easily destroyed by the energy from the sound waves but newer agents have proved to last for longer time and hereby enable real-time scanning and make contrast enhancement suitable for interventional procedures such as biopsies and tissue ablation. Also, in monitoring the effect of tumour treatment contrast agents have been useful. A brief overview is given on some possible applications and on different techniques using ultrasound contrast agents in liver imaging. At present, the use of an ultrasound contrast agent that allows real-time scanning with low mechanical index is to be preferred

  2. Lesion Contrast Enhancement in Medical Ultrasound Imaging

    DEFF Research Database (Denmark)

    Stetson, Paul F.; Sommer, F.G.; Macovski, A.

    1997-01-01

    Methods for improving the contrast-to-noise ratio (CNR) of low-contrast lesions in medical ultrasound imaging are described. Differences in the frequency spectra and amplitude distributions of the lesion and its surroundings can be used to increase the CNR of the lesion relative to the background...

  3. Cumulative phase delay imaging for contrast-enhanced ultrasound tomography

    International Nuclear Information System (INIS)

    Demi, Libertario; Van Sloun, Ruud J G; Wijkstra, Hessel; Mischi, Massimo

    2015-01-01

    Standard dynamic-contrast enhanced ultrasound (DCE-US) imaging detects and estimates ultrasound-contrast-agent (UCA) concentration based on the amplitude of the nonlinear (harmonic) components generated during ultrasound (US) propagation through UCAs. However, harmonic components generation is not specific to UCAs, as it also occurs for US propagating through tissue. Moreover, nonlinear artifacts affect standard DCE-US imaging, causing contrast to tissue ratio reduction, and resulting in possible misclassification of tissue and misinterpretation of UCA concentration. Furthermore, no contrast-specific modality exists for DCE-US tomography; in particular speed-of-sound changes due to UCAs are well within those caused by different tissue types. Recently, a new marker for UCAs has been introduced. A cumulative phase delay (CPD) between the second harmonic and fundamental component is in fact observable for US propagating through UCAs, and is absent in tissue. In this paper, tomographic US images based on CPD are for the first time presented and compared to speed-of-sound US tomography. Results show the applicability of this marker for contrast specific US imaging, with cumulative phase delay imaging (CPDI) showing superior capabilities in detecting and localizing UCA, as compared to speed-of-sound US tomography. Cavities (filled with UCA) which were down to 1 mm in diameter were clearly detectable. Moreover, CPDI is free of the above mentioned nonlinear artifacts. These results open important possibilities to DCE-US tomography, with potential applications to breast imaging for cancer localization. (fast track communication)

  4. Estimation of Tumor Angiogenesis With Contrast Enhanced Subharmonic Ultrasound Imaging

    National Research Council Canada - National Science Library

    Forsberg, Flemming

    2005-01-01

    ...) and receiving at the subharmonic (f0). Hence, the current project proposes to increase the ability of breast ultrasound to differentiate between benign and malignant lesions by combining injection of an ultrasound contrast agent with SHI...

  5. Estimation of Tumor Angiogenesis With Contrast Enhanced Subharmonic Ultrasound Imaging

    National Research Council Canada - National Science Library

    Forsberg, Flemming

    2002-01-01

    .... Hence, the current project proposes to increase the ability of breast ultrasound to differentiate between benign and malignant lesions by combining injection of an ultrasound contrast agent with SHI...

  6. Estimation of Tumor Angiogenesis with Contrast Enhanced Subharmonic Ultrasound Imaging

    National Research Council Canada - National Science Library

    Forsberg, Flemming

    2004-01-01

    .... Hence, the current project proposes to increase the ability of breast ultrasound to differentiate between benign and malignant lesions by combining injection of an ultrasound contrast agent with SHI...

  7. Comparison of Oral Contrast-Enhanced Transabdominal Ultrasound Imaging With Transverse Contrast-Enhanced Computed Tomography in Preoperative Tumor Staging of Advanced Gastric Carcinoma.

    Science.gov (United States)

    He, Xuemei; Sun, Jing; Huang, Xiaoling; Zeng, Chun; Ge, Yinggang; Zhang, Jun; Wu, Jingxian

    2017-12-01

    This study assessed the diagnostic performance of transabdominal oral contrast-enhanced ultrasound (US) imaging for preoperative tumor staging of advanced gastric carcinoma by comparing it with transverse contrast-enhanced computed tomography (CT). This retrospective study included 42 patients with advanced gastric cancer who underwent laparoscopy, radical surgery, or palliative surgery because of serious complications and had a body mass index of less than 25 kg/m 2 . A cereal-based oral contrast agent was used for transabdominal oral contrast-enhanced US. Retrospective analyses were conducted using preoperative tumor staging data acquired by either transabdominal oral contrast-enhanced US or transverse contrast-enhanced CT. Both contrast-enhanced US and contrast-enhanced CT examinations were reviewed by 2 experienced radiologists independently for preoperative tumor staging according to the seventh edition of the TNM classification. The accuracy, sensitivity, and specificity were calculated by comparing the results of contrast-enhanced US and contrast-enhanced CT with pathologic findings. The overall accuracies of the imaging modalities were compared by the McNemar test. No significant difference was noted in the overall accuracy of transabdominal oral contrast-enhanced US (86% [36 of 42]) and transverse contrast-enhanced CT (83% [35 of 42] P > .999). For stage T2 to T4 gastric cancer, the accuracies of transabdominal oral contrast-enhanced US were 88%, 86%, and 98%, respectively, and those of transverse contrast-enhanced CT were 93%, 83%, and 90%. The overall accuracy of transabdominal oral contrast-enhanced US was comparable with that of transverse contrast-enhanced CT for preoperative tumor staging of advanced gastric cancer. © 2017 by the American Institute of Ultrasound in Medicine.

  8. Microbubble Composition and Preparation for High-Frequency Contrast-Enhanced Ultrasound Imaging : In Vitro and in Vivo Evaluation

    NARCIS (Netherlands)

    Daeichin, Verya; van Rooij, Tom; Skachkov, Ilya; Ergin, Bulent; Specht, Patricia A.C.; Lima, Alexandre; Ince, Can; Bosch, Johan G.; van der Steen, A.F.W.; de Jong, N.; Kooiman, Klazina

    2017-01-01

    Although high-frequency ultrasound imaging is gaining attention in various applications, hardly any ultrasound contrast agents (UCAs) dedicated to such frequencies (>15 MHz) are available for contrast-enhanced ultrasound (CEUS) imaging. Moreover, the composition of the limited commercially

  9. Microbubble Composition and Preparation for High-Frequency Contrast-Enhanced Ultrasound Imaging: In Vitro and In Vivo Evaluation

    NARCIS (Netherlands)

    Daeichin, Verya; van Rooij, Tom; Skachkov, Ilya; Ergin, Bulent; Specht, Patricia A. C.; Lima, Alexandre; Ince, Can; Bosch, Johan G.; van der Steen, Antonius F. W.; de Jong, Nico; Kooiman, Klazina

    2017-01-01

    Although high-frequency ultrasound imaging is gaining attention in various applications, hardly any ultrasound contrast agents (UCAs) dedicated to such frequencies (>15 MHz) are available for contrast-enhanced ultrasound (CEUS) imaging. Moreover, the composition of the limited commercially available

  10. Microbubble Composition and Preparation for High-Frequency Contrast-Enhanced Ultrasound Imaging: In Vitro and in Vivo Evaluation

    NARCIS (Netherlands)

    V. Daeichin (Verya); T. van Rooij (Tom); I. Skachkov (Ilya); B. Ergin (Bulent); P. Specht (Patricia); A.A.P. Lima (Alexandre ); C. Ince (Can); J.G. Bosch (Hans); A.F.W. van der Steen (Ton); N. de Jong (Nico); K. Kooiman (Klazina)

    2017-01-01

    textabstractAlthough high-frequency ultrasound imaging is gaining attention in various applications, hardly any ultrasound contrast agents (UCAs) dedicated to such frequencies (>15 MHz) are available for contrast-enhanced ultrasound (CEUS) imaging. Moreover, the composition of the limited

  11. Counter-propagating wave interaction for contrast-enhanced ultrasound imaging

    Science.gov (United States)

    Renaud, G.; Bosch, J. G.; ten Kate, G. L.; Shamdasani, V.; Entrekin, R.; de Jong, N.; van der Steen, A. F. W.

    2012-11-01

    Most techniques for contrast-enhanced ultrasound imaging require linear propagation to detect nonlinear scattering of contrast agent microbubbles. Waveform distortion due to nonlinear propagation impairs their ability to distinguish microbubbles from tissue. As a result, tissue can be misclassified as microbubbles, and contrast agent concentration can be overestimated; therefore, these artifacts can significantly impair the quality of medical diagnoses. Contrary to biological tissue, lipid-coated gas microbubbles used as a contrast agent allow the interaction of two acoustic waves propagating in opposite directions (counter-propagation). Based on that principle, we describe a strategy to detect microbubbles that is free from nonlinear propagation artifacts. In vitro images were acquired with an ultrasound scanner in a phantom of tissue-mimicking material with a cavity containing a contrast agent. Unlike the default mode of the scanner using amplitude modulation to detect microbubbles, the pulse sequence exploiting counter-propagating wave interaction creates no pseudoenhancement behind the cavity in the contrast image.

  12. Contrast-enhanced harmonic ultrasound imaging in ablation therapy for primary hepatocellular carcinoma.

    Science.gov (United States)

    Minami, Yasunori; Kudo, Masatoshi

    2009-12-31

    The success rate of percutaneous radiofrequency (RF) ablation for hepatocellular carcinoma (HCC) depends on correct targeting via an imaging technique. However, RF electrode insertion is not completely accurate for residual HCC nodules because B-mode ultrasound (US), color Doppler, and power Doppler US findings cannot adequately differentiate between treated and viable residual tumor tissue. Electrode insertion is also difficult when we must identify the true HCC nodule among many large regenerated nodules in cirrhotic liver. Two breakthroughs in the field of US technology, harmonic imaging and the development of second-generation contrast agents, have recently been described and have demonstrated the potential to dramatically broaden the scope of US diagnosis of hepatic lesions. Contrast-enhanced harmonic US imaging with an intravenous contrast agent can evaluate small hypervascular HCC even when B-mode US cannot adequately characterize tumor. Therefore, contrast-enhanced harmonic US can facilitate RF ablation electrode placement in hypervascular HCC, which is poorly depicted by B-mode US. The use of contrast-enhanced harmonic US in ablation therapy for liver cancer is an efficient approach.

  13. Contrast-enhanced ultrasound imaging of active bleeding associated with hepatic and splenic trauma.

    Science.gov (United States)

    Lv, F; Tang, J; Luo, Y; Li, Z; Meng, X; Zhu, Z; Li, T

    2011-10-01

    The aim of this study was to evaluate contrast-enhanced ultrasound (CEUS) imaging of active bleeding from hepatic and splenic trauma. Three hundred and ninety-two patients with liver or/and spleen trauma (179 liver and 217 spleen injuries), who underwent CEUS examinations following contrast-enhanced computed tomography (CT), were enrolled in this retrospective study over a period of >4 years. CEUS detected contrast medium extravasation or pooling in 16% (63/396) of liver or spleen lesions in 61 patients, which was confirmed by contrast-enhanced CT. Special attention was paid to observing the presence, location, and characteristics of the extravasated or pooled contrast medium. The CEUS detection rate for active bleeding was not different from that of contrast-enhanced CT (p=0.333). Information from surgery, minimally invasive treatment and conservative treatment was used as reference standard, and the sensitivities of the two techniques were not different (p=0.122). Of 63 lesions in 61 patients, CEUS showed that 74.6% (47/63) (21 liver lesions and 26 spleen lesions) presented contrast medium extravasation or pooling, both in the organ and out the capsule, in 14.3% (9/63) and only outside the capsule in 11.1% (7/63). CEUS imaging of active bleeding from hepatic and splenic trauma presented various characteristics, and the sizes and shapes of the active bleeding due to contrast medium extravasation or pooling were variable. CEUS can show the active bleeding associated with hepatic and splenic trauma with various imaging characteristics, thus making it possible to diagnose active bleeding using CEUS.

  14. International guidelines for contrast-enhanced ultrasonography: Ultrasound imaging in the new millennium

    International Nuclear Information System (INIS)

    Nolsoe, Christian Pallson; Lorentzen, Torben

    2016-01-01

    The intent of this review is to discuss and comment on common clinical scenarios in which contrast-enhanced ultrasonography (CEUS) may play a decisive role and to illustrate important points with typical cases. With the advent of CEUS, the scope of indications for ultrasonography has been dramatically extended, and now includes functional imaging and tissue characterization, which in many cases enable tumor diagnosis without a biopsy. It is virtually impossible to imagine the practice of modern medicine as we know it in high-income countries without the use of imaging, and yet, an estimated two thirds of the global population may receive no such care. Ultrasound imaging with CEUS has the potential to correct this inequity

  15. International guidelines for contrast-enhanced ultrasonography: Ultrasound imaging in the new millennium

    Energy Technology Data Exchange (ETDEWEB)

    Nolsoe, Christian Pallson; Lorentzen, Torben [Ultrasound Section, Dept. of Gastric Surgery, Herlev Hospital, University of Copenhagen, Herlev (Denmark)

    2016-03-15

    The intent of this review is to discuss and comment on common clinical scenarios in which contrast-enhanced ultrasonography (CEUS) may play a decisive role and to illustrate important points with typical cases. With the advent of CEUS, the scope of indications for ultrasonography has been dramatically extended, and now includes functional imaging and tissue characterization, which in many cases enable tumor diagnosis without a biopsy. It is virtually impossible to imagine the practice of modern medicine as we know it in high-income countries without the use of imaging, and yet, an estimated two thirds of the global population may receive no such care. Ultrasound imaging with CEUS has the potential to correct this inequity.

  16. Counter-propagating wave interaction for contrast-enhanced ultrasound imaging

    International Nuclear Information System (INIS)

    Renaud, G; Bosch, J G; Ten Kate, G L; De Jong, N; Van der Steen, A F W; Shamdasani, V; Entrekin, R

    2012-01-01

    Most techniques for contrast-enhanced ultrasound imaging require linear propagation to detect nonlinear scattering of contrast agent microbubbles. Waveform distortion due to nonlinear propagation impairs their ability to distinguish microbubbles from tissue. As a result, tissue can be misclassified as microbubbles, and contrast agent concentration can be overestimated; therefore, these artifacts can significantly impair the quality of medical diagnoses. Contrary to biological tissue, lipid-coated gas microbubbles used as a contrast agent allow the interaction of two acoustic waves propagating in opposite directions (counter-propagation). Based on that principle, we describe a strategy to detect microbubbles that is free from nonlinear propagation artifacts. In vitro images were acquired with an ultrasound scanner in a phantom of tissue-mimicking material with a cavity containing a contrast agent. Unlike the default mode of the scanner using amplitude modulation to detect microbubbles, the pulse sequence exploiting counter-propagating wave interaction creates no pseudoenhancement behind the cavity in the contrast image. (fast track communication)

  17. Volume navigation with contrast enhanced ultrasound and image fusion for percutaneous interventions: first results.

    Directory of Open Access Journals (Sweden)

    Ernst Michael Jung

    Full Text Available OBJECTIVE: Assessing the feasibility and efficiency of interventions using ultrasound (US volume navigation (V Nav with real time needle tracking and image fusion with contrast enhanced (ce CT, MRI or US. METHODS: First an in vitro study on a liver phantom with CT data image fusion was performed, involving the puncture of a 10 mm lesion in a depth of 5 cm performed by 15 examiners with US guided freehand technique vs. V Nav for the purpose of time optimization. Then 23 patients underwent ultrasound-navigated biopsies or interventions using V Nav image fusion of live ultrasound with ceCT, ceMRI or CEUS, which were acquired before the intervention. A CEUS data set was acquired in all patients. Image fusion was established for CEUS and CT or CEUS and MRI using anatomical landmarks in the area of the targeted lesion. The definition of a virtual biopsy line with navigational axes targeting the lesion was achieved by the usage of sterile trocar with a magnetic sensor embedded in its distal tip employing a dedicated navigation software for real time needle tracking. RESULTS: The in vitro study showed significantly less time needed for the simulated interventions in all examiners when V Nav was used (p<0.05. In the study involving patients, in all 10 biopsies of suspect lesions of the liver a histological confirmation was achieved. We also used V Nav for a breast biopsy (intraductal carcinoma, for a biopsy of the abdominal wall (metastasis of ovarial carcinoma and for radiofrequency ablations (4 ablations. In 8 cases of inflammatory abdominal lesions 9 percutaneous drainages were successfully inserted. CONCLUSION: Percutaneous biopsies and drainages, even of small lesions involving complex access pathways, can be accomplished with a high success rate by using 3D real time image fusion together with real time needle tracking.

  18. Parametric imaging for characterizing focal liver lesions in contrast-enhanced ultrasound.

    Science.gov (United States)

    Rognin, Nicolas G; Arditi, Marcel; Mercier, Laurent; Frinking, Peter J A; Schneider, Michel; Perrenoud, Geneviève; Anaye, Anass; Meuwly, Jean-Yves; Tranquart, François

    2010-11-01

    The differentiation between benign and malignant focal liver lesions plays an important role in diagnosis of liver disease and therapeutic planning of local or general disease. This differentiation, based on characterization, relies on the observation of the dynamic vascular patterns (DVP) of lesions with respect to adjacent parenchyma, and may be assessed during contrast-enhanced ultrasound imaging after a bolus injection. For instance, hemangiomas (i.e., benign lesions) exhibit hyper-enhanced signatures over time, whereas metastases (i.e., malignant lesions) frequently present hyperenhanced foci during the arterial phase and always become hypo-enhanced afterwards. The objective of this work was to develop a new parametric imaging technique, aimed at mapping the DVP signatures into a single image called a DVP parametric image, conceived as a diagnostic aid tool for characterizing lesion types. The methodology consisted in processing a time sequence of images (DICOM video data) using four consecutive steps: (1) pre-processing combining image motion correction and linearization to derive an echo-power signal, in each pixel, proportional to local contrast agent concentration over time; (2) signal modeling, by means of a curve-fitting optimization, to compute a difference signal in each pixel, as the subtraction of adjacent parenchyma kinetic from the echopower signal; (3) classification of difference signals; and (4) parametric image rendering to represent classified pixels as a support for diagnosis. DVP parametric imaging was the object of a clinical assessment on a total of 146 lesions, imaged using different medical ultrasound systems. The resulting sensitivity and specificity were 97% and 91%, respectively, which compare favorably with scores of 81 to 95% and 80 to 95% reported in medical literature for sensitivity and specificity, respectively.

  19. Novel fluorescence nanobubbles for contrast-enhanced ultrasound imaging in rabbit VX2 hepatocellular carcinoma model

    Science.gov (United States)

    Yu, Houqiang; Wang, Wei; He, Xiaoling; Zhou, Qibing; Ding, Mingyue

    2017-03-01

    Ultrasound contrast agents (UCAs) such as SonoVue or Optison have been used widely in clinic for contrast-enhanced vascular imaging. However, microbubbles UCAs display limitations in tumor-targeted imaging due to the large sizes, nanoscaled UCAs has consequently attracted increasing attentions. In this work, we synthesized nanobubbles (NBs) by ultrasonic cavitation method, then a fluorescent marker of Alexa Fluor 680 was conjugated to the shell in order to observe the localization of NBs in tumor tissue. Measurement of fundamental characteristics showed that the NBs had homogeneous distribution of mean diameter of 267.9 +/- 19.2 nm and polydispersity index of 0.410 +/- 0.056. To assess in vivo tumor-selectivity of NBs, we established the rabbits VX2 hepatocellular carcinoma model though surgical implantation method. After the rabbits were intravenous administered of NBs, contrast-enhanced sonograms was observed in the surrounding of VX2 tumor, which showed there are rich capillaries in the tumor periphery. We additionally investigated the toxic of the NBs by hematoxylin-eosin staining. The results indicated that the NBs is a biocompatible non-toxic lipid system. Furthermore, the VX2 tumors and major organs were analyzed using ex vivo fluorescence imaging to confirm the targeted selectivity of NBs, and the results verified that the NBs were capable of targeting VX2 tumor. Confocal laser scanning microscopy examination showed that the NBs can traverse the VX2 tumor capillaries and target to the hepatocellular carcinoma tumor cells. All these results suggested that the newly prepared NBs have a potential application in molecular imaging and tumor-targeting therapy.

  20. Epithelial cell biocompatibility of silica nanospheres for contrast-enhanced ultrasound molecular imaging

    Energy Technology Data Exchange (ETDEWEB)

    Chiriaco, Fernanda; Conversano, Francesco; Soloperto, Giulia; Casciaro, Ernesto [Institute of Clinical Physiology, Bioengineering Division, National Research Council (Italy); Ragusa, Andrea [National Nanotechnology Laboratory of CNR-NANO (Italy); Sbenaglia, Enzo Antonio; Dipaola, Lucia [Institute of Clinical Physiology, Bioengineering Division, National Research Council (Italy); Casciaro, Sergio, E-mail: sergio.casciaro@cnr.it [Istituto di Fisiologia Clinica (CNR-IFC) c/o Campus Universitario Ecotekne, Consiglio Nazionale delle Ricerche (Italy)

    2013-07-15

    Nanosized particles are receiving increasing attention as future contrast agents (CAs) for ultrasound (US) molecular imaging, possibly decorated on its surface with biological recognition agents for targeted delivery and deposition of therapeutics. In particular, silica nanospheres (SiNSs) have been demonstrated to be feasible in terms of contrast enhancement on conventional US systems. In this work, we evaluated the cytotoxicity of SiNSs on breast cancer (MCF-7) and HeLa (cervical cancer) cells employing NSs with sizes ranging from 160 to 330 nm and concentration range of 1.5-5 mg/mL. Cell viability was evaluated in terms of size, dose and time dependence, performing the MTT reduction assay with coated and uncoated SiNSs. Whereas uncoated SiNSs caused a variable significant decrease in cell viability on both cell lines mainly depending on size and exposure time, PEGylated SiNSs (SiNSs-PEG) exhibit a high level of biocompatibility. In fact, after 72-h incubation, viability of both cell types was above the cutoff value of 70 % at concentration up to 5 mg/mL. We also investigated the acoustical behavior of coated and uncoated SiNSs within conventional diagnostic US fields in order to determine a suitable configuration, in terms of particle size and concentration, for their employment as targetable CAs. Our results indicate that the employment of SiNSs with diameters around 240 nm assures the most effective contrast enhancement even at the lowest tested concentration, coupled with the possibility of targeting all tumor tissues, being the SiNSs still in a size range where reticuloendothelial system trapping effect is relatively low.

  1. Epithelial cell biocompatibility of silica nanospheres for contrast-enhanced ultrasound molecular imaging

    International Nuclear Information System (INIS)

    Chiriacò, Fernanda; Conversano, Francesco; Soloperto, Giulia; Casciaro, Ernesto; Ragusa, Andrea; Sbenaglia, Enzo Antonio; Dipaola, Lucia; Casciaro, Sergio

    2013-01-01

    Nanosized particles are receiving increasing attention as future contrast agents (CAs) for ultrasound (US) molecular imaging, possibly decorated on its surface with biological recognition agents for targeted delivery and deposition of therapeutics. In particular, silica nanospheres (SiNSs) have been demonstrated to be feasible in terms of contrast enhancement on conventional US systems. In this work, we evaluated the cytotoxicity of SiNSs on breast cancer (MCF-7) and HeLa (cervical cancer) cells employing NSs with sizes ranging from 160 to 330 nm and concentration range of 1.5–5 mg/mL. Cell viability was evaluated in terms of size, dose and time dependence, performing the MTT reduction assay with coated and uncoated SiNSs. Whereas uncoated SiNSs caused a variable significant decrease in cell viability on both cell lines mainly depending on size and exposure time, PEGylated SiNSs (SiNSs-PEG) exhibit a high level of biocompatibility. In fact, after 72-h incubation, viability of both cell types was above the cutoff value of 70 % at concentration up to 5 mg/mL. We also investigated the acoustical behavior of coated and uncoated SiNSs within conventional diagnostic US fields in order to determine a suitable configuration, in terms of particle size and concentration, for their employment as targetable CAs. Our results indicate that the employment of SiNSs with diameters around 240 nm assures the most effective contrast enhancement even at the lowest tested concentration, coupled with the possibility of targeting all tumor tissues, being the SiNSs still in a size range where reticuloendothelial system trapping effect is relatively low

  2. The 'humble' bubble: Contrast-enhanced ultrasound

    International Nuclear Information System (INIS)

    Marshall, Gill; Sykes, Anne; Berry, Jonathan; Jonker, Leon

    2011-01-01

    The use of contrast-enhanced ultrasound (CEUS) is increasing within the field of medical imaging. Ultrasonic contrast agent (UCA) contain gas microbubbles similar in size to red corpuscles which provide highly reflective interfaces, enabling dynamic demonstration of echogenic streams of the contrast within the anatomical area of interest on real-time grey scale ultrasound. Longevity of the microbubbles has been improved by changing their composition. The application of CEUS in the UK continues to grow, bringing it into territories historically occupied by computerised tomography (CT) scanning and magnetic resonance imaging (MRI). Hence, the role of CEUS may be of interest to all diagnostic imaging practitioners. Here we summarise the mode of action and use of CEUS, and its role within a range of applications. The potential risks of CEUS are compared to other contrast-enhanced imaging techniques. The benefits of CEUS and its implications for diagnostic imaging practice are also covered.

  3. Contrast-enhanced harmonic endoscopic ultrasound

    DEFF Research Database (Denmark)

    Săftoiu, A; Dietrich, C F; Vilmann, P

    2012-01-01

    Second-generation intravenous blood-pool ultrasound contrast agents are increasingly used in endoscopic ultrasound (EUS) for characterization of microvascularization, differential diagnosis of benign and malignant focal lesions, and improving staging and guidance of therapeutic procedures. Although...... initially used as Doppler signal enhancers, second-generation microbubble contrast agents are now used with specific contrast harmonic imaging techniques, which benefit from the highly nonlinear behavior of the microbubbles. Contrast-specific modes based on multi-pulse technology are used to perform...... contrast-enhanced harmonic EUS based on a very low mechanical index (0.08 - 0.12). Quantification techniques based on dynamic contrast-enhanced ultrasound have been recommended for perfusion imaging and monitoring of anti-angiogenic treatment, mainly based on time-intensity curve analysis. Most...

  4. Characterizing EPR-mediated passive drug targeting using contrast-enhanced functional ultrasound imaging.

    Science.gov (United States)

    Theek, Benjamin; Gremse, Felix; Kunjachan, Sijumon; Fokong, Stanley; Pola, Robert; Pechar, Michal; Deckers, Roel; Storm, Gert; Ehling, Josef; Kiessling, Fabian; Lammers, Twan

    2014-05-28

    The Enhanced Permeability and Retention (EPR) effect is extensively used in drug delivery research. Taking into account that EPR is a highly variable phenomenon, we have here set out to evaluate if contrast-enhanced functional ultrasound (ceUS) imaging can be employed to characterize EPR-mediated passive drug targeting to tumors. Using standard fluorescence molecular tomography (FMT) and two different protocols for hybrid computed tomography-fluorescence molecular tomography (CT-FMT), the tumor accumulation of a ~10 nm-sized near-infrared-fluorophore-labeled polymeric drug carrier (pHPMA-Dy750) was evaluated in CT26 tumor-bearing mice. In the same set of animals, two different ceUS techniques (2D MIOT and 3D B-mode imaging) were employed to assess tumor vascularization. Subsequently, the degree of tumor vascularization was correlated with the degree of EPR-mediated drug targeting. Depending on the optical imaging protocol used, the tumor accumulation of the polymeric drug carrier ranged from 5 to 12% of the injected dose. The degree of tumor vascularization, determined using ceUS, varied from 4 to 11%. For both hybrid CT-FMT protocols, a good correlation between the degree of tumor vascularization and the degree of tumor accumulation was observed, within the case of reconstructed CT-FMT, correlation coefficients of ~0.8 and p-values of EPR, and potentially also to pre-select patients likely to respond to passively tumor-targeted nanomedicine treatments. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. 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.

  6. Contrast enhanced ultrasound of sentinel lymph nodes

    Directory of Open Access Journals (Sweden)

    XinWu Cui

    2013-03-01

    Full Text Available Sentinel lymph nodes are the first lymph nodes in the region that receive lymphatic drainage from a primary tumor. The detection or exclusion of sentinel lymph node micrometastases is critical in the staging of cancer, especially breast cancer and melanoma because it directly affects patient’s prognosis and surgical management. Currently, intraoperative sentinel lymph node biopsies using blue dye and radioisotopes are the method of choice for the detection of sentinel lymph node with high identification rate. In contrast, conventional ultrasound is not capable of detecting sentinel lymph nodes in most cases. Contrast enhanced ultrasound with contrast specific imaging modes has been used for the evaluation and diagnostic work-up of peripherally located suspected lymphadenopathy. The method allows for real-time analysis of all vascular phases and the visualization of intranodal focal “avascular” areas that represent necrosis or deposits of neoplastic cells. In recent years, a number of animal and human studies showed that contrast enhanced ultrasound can be also used for the detection of sentinel lymph node, and may become a potential application in clinical routine. Several contrast agents have been used in those studies, including albumin solution, hydroxyethylated starch, SonoVue®, Sonazoid® and Definity®. This review summarizes the current knowledge about the use of ultrasound techniques in detection and evaluation of sentinel lymph node.

  7. Combining multi-pulse excitation and chirp coding in contrast-enhanced ultrasound imaging

    International Nuclear Information System (INIS)

    Crocco, M; Sciallero, C; Trucco, A; Pellegretti, P

    2009-01-01

    The development of techniques to separate the response of the contrast agent from that of the biological tissues is of great importance in ultrasound medical imaging. In the literature, one can find various solutions involving the use of multiple transmitted signals and the weighted sum of related echoes. In this paper, the combination of one of these multi-pulse techniques with a coded excitation is proposed and assessed. Coded excitation has been used mainly to increase the signal-to-noise ratio (SNR) and the penetration depth, provided that a matched filtering is applied in the reception chain. However, it has been shown that a signal with a long duration time also increases the backscattered echoes produced by the microbubbles and, consequently, the contrast-to-tissue ratio. Therefore, the implementation of a multi-pulse technique using a long coded pulse can yield a better contrast-to-tissue ratio and SNR. This paper investigates the combination of the linear chirp pulse with a multi-pulse technique based on the transmission of three pulses. The performance was evaluated using both simulated and real signals, assessing the improvement in the contrast-to-tissue ratio and SNR, the visual quality of the images obtained and the axial accuracy. A comparison with the same multi-pulse technique implemented using a traditional amplitude-modulated pulse revealed that the deployment of a chirp pulse produces several noticeable advantages and only a minor drawback

  8. Contrast-Enhanced Ultrasound in Vascular Surgery

    DEFF Research Database (Denmark)

    Bredahl, Kim; Mestre, Xavier Marti; Coll, Ramon Vila

    2017-01-01

    modalities. Ultrasound has only challenged these methods in assessment of carotid disease, aortic aneurysms, venous insufficiency, and thromboembolism and in surveillance of in situ bypasses. These practice patterns may change with the introduction of second-generation ultrasound contrast agents which...... are easy to use, manageable, and safe. This topical review attempts to summarize and highlight the current evidence and future prospects for contrast-enhanced ultrasound in vascular surgery, with a particular focus on opportunities in carotid and lower limb arteriosclerotic disease and surveillance after...

  9. Semi-automatic motion compensation of contrast-enhanced ultrasound images from abdominal organs for perfusion analysis

    Czech Academy of Sciences Publication Activity Database

    Schafer, S.; Nylund, K.; Saevik, F.; Engjom, T.; Mézl, M.; Jiřík, Radovan; Dimcevski, G.; Gilja, O.H.; Tönnies, K.

    2015-01-01

    Roč. 63, AUG 1 (2015), s. 229-237 ISSN 0010-4825 R&D Projects: GA ČR GAP102/12/2380 Institutional support: RVO:68081731 Keywords : ultrasonography * motion analysis * motion compensation * registration * CEUS * contrast-enhanced ultrasound * perfusion * perfusion modeling Subject RIV: FS - Medical Facilities ; Equipment Impact factor: 1.521, year: 2015

  10. An Algorithm of Image Heterogeneity with Contrast-Enhanced Ultrasound in Differential Diagnosis of Solid Thyroid Nodules.

    Science.gov (United States)

    Jin, Lifang; Xu, Changsong; Xie, Xueqian; Li, Fan; Lv, Xiuhong; Du, Lianfang

    2017-01-01

    Enhancement heterogeneity on contrast-enhanced ultrasonography (CEUS) is used to differentiate between benign and malignant thyroid nodules. In this study, we used an algorithm to quantify enhancement heterogeneity of solid thyroid nodules on CEUS. The heterogeneity value (HV) is calculated as standard deviation/mean intensity × 100 (using Adobe Photoshop). The heterogeneity ratio (HR) is calculated as the ratio of the HV of the nodule to that of the surrounding parenchyma. Three phases-ascending, peak and descending phases-were studied. HV values at ascending (HV a ) and peak (HV p ) phases were significantly higher in malignant nodules than in benign nodules (95.57 ± 43.87 vs. 73.06 ± 44.04, p = 0.009, and 32.53 ± 10.73 vs. 26.44 ± 8.25, p = 0.002, respectively). HR a , HR p and HR d were significantly higher in malignant nodules than in benign nodules (1.93 ± 1.03 vs. 1.00 ± 0.47, p = 0.000, 1.43 ± 0.51 vs. 1.09 ± 0.28, p = 0.000, and 1.33 ± 0.40 vs. 1.08 ± 0.33, p = 0.001, respectively). HR a achieved optimal diagnostic performance on receiver operating characteristic curve analysis. The algorithm used for assessment of image heterogeneity on CEUS examination may be a useful adjunct to conventional ultrasound for differential diagnosis of solid thyroid nodules. Copyright © 2016 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  11. Data on consistency among different methods to assess atherosclerotic plaque echogenicity on standard ultrasound and intraplaque neovascularization on contrast-enhanced ultrasound imaging in human carotid artery

    Directory of Open Access Journals (Sweden)

    Mattia Cattaneo

    2016-12-01

    Full Text Available Here we provide the correlation among different carotid ultrasound (US variables to assess echogenicity n standard carotid US and to assess intraplaque neovascularization on contrast enhanced US. We recruited 45 consecutive subjects with an asymptomatic≥50% carotid artery stenosis. Carotid plaque echogenicity at standard US was visually graded according to Gray–Weale classification (GW and measured by the greyscale median (GSM, a semi-automated computerized measurement performed by Adobe Photoshop®. On CEUS imaging IPNV was graded according to the visual appearance of contrast within the plaque according to three different methods: CEUS_A (1=absent; 2=present; CEUS_B a three-point scale (increasing IPNV from 1 to 3; CEUS_C a four-point scale (increasing IPNV from 0 to 3. We have also implemented a new simple quantification method derived from region of interest (ROI signal intensity ratio as assessed by QLAB software. Further information is available in “Contrast-enhanced ultrasound imaging of intraplaque neovascularization and its correlation to plaque echogenicity in human carotid arteries atherosclerosis (M. Cattaneo, D. Staub, A.P. Porretta, J.M. Gallino, P. Santini, C. Limoni et al., 2016 [1].

  12. Dynamic Contrast-Enhanced Ultrasound of Colorectal Liver Metastases as an Imaging Modality for Early Response Prediction to Chemotherapy

    DEFF Research Database (Denmark)

    Mogensen, Marie Benzon; Hansen, Martin Lundsgaard; Henriksen, Birthe Merete

    2017-01-01

    Our aim was to investigate whether dynamic contrast-enhanced ultrasound (DCE-US) can detect early changes in perfusion of colorectal liver metastases after initiation of chemotherapy. Newly diagnosed patients with colorectal cancer with liver metastases were enrolled in this explorative prospective...... study. Patients were treated with capecitabine or 5-fluorouracil-based chemotherapy with or without bevacizumab. DCE-US was performed before therapy (baseline) and again 10 days after initiation of treatment. Change in contrast-enhancement in one liver metastasis (indicator lesion) was measured....... Treatment response was evaluated with a computed tomography (CT) scan after three cycles of treatment and the initially observed DCE-US change of the indicator lesion was related to the observed CT response. Eighteen patients were included. Six did not complete three series of chemotherapy...

  13. Contrast-enhanced ultrasound of the kidneys

    NARCIS (Netherlands)

    Beemster, P.; Pes, P.L.; Wijkstra, H.

    2009-01-01

    Several imaging techniques can be used for visualization of the kidneys dependent on the indication. Ultrasound (US), computerized tomography (CT), and magnetic resonance imaging (MRI) are most commonly used. US is a safe, relatively inexpensive, noninvasive, and widely available imaging method. It

  14. Contrast enhanced ultrasound of splenic lymphoma involvement

    International Nuclear Information System (INIS)

    Goerg, Christian; Faoro, Charis; Bert, Tillmann; Tebbe, Johannes; Neesse, Albrecht; Wilhelm, Christian

    2011-01-01

    Objective: The aim of this study was to compare the value of contrast-enhanced ultrasonography (CEUS) with standard B-mode ultrasound (US) for diagnosis of splenic lymphoma involvement. Methods: From 04/2005 to 10/2008 n = 250 lymphoma patients were investigated by standard B-mode US. A homogeneous splenic echotexture was found in 199 patients (79%). To clarify the benefit of CEUS in this group a pilot series was performed with 16 of the 199 lymphoma patients. All patients with an abnormal splenic echotexture on standard B-Mode US (n = 51) including focal hypoechoic splenic lesions (n = 41) and an inhomogeneous splenic texture (n = 10) were studied by CEUS. CEUS data were retrospectively evaluated. The diagnoses included indolent lymphoma (n = 27), aggressive lymphoma (n = 14), and Hodgkin's disease (n = 10). Number and size of lesions were determined by B-mode US and CEUS. The visualisation of splenic lymphoma involvement by CEUS in comparison to B-mode US was classified as worse, equal, or better. Results: All patients with a homogeneous spleen on B-mode US (n = 16) had no visible focal lesions on CEUS. Study patients with focal lesions (n = 41) had a hypoechoic (n = 22) or isoechoic (n = 19) enhancement during the arterial phase, and a hypoechoic enhancement during the parenchymal phase (n = 41). The visualisation of focal splenic lymphoma was equal (n = 32), better (n = 6), or worse (n = 3). In all study patients with an inhomogeneous spleen on B-mode US (n = 10) no focal lesions were found by CEUS and the value of CEUS therefore was classified as worse. Conclusion: CEUS has no clear advantage for diagnosis of splenic lymphoma involvement.

  15. Contrast enhanced ultrasound of splenic lymphoma involvement

    Energy Technology Data Exchange (ETDEWEB)

    Goerg, Christian, E-mail: goergc@med.uni-marburg.de [Medizinische Universitaetsklinik, Baldingerstrasse, 35033 Marburg/Lahn (Germany); Faoro, Charis [Medizinische Universitaetsklinik, Baldingerstrasse, 35033 Marburg/Lahn (Germany); Bert, Tillmann [Zentralklinik Bad Berka GmbH, Robert-Koch-Allee 9, 99437 Bad Berka (Germany); Tebbe, Johannes [Klinikum Lippe-Detmold, Roentgenstrasse 18, 32756 Detmold (Germany); Neesse, Albrecht; Wilhelm, Christian [Medizinische Universitaetsklinik, Baldingerstrasse, 35033 Marburg/Lahn (Germany)

    2011-11-15

    Objective: The aim of this study was to compare the value of contrast-enhanced ultrasonography (CEUS) with standard B-mode ultrasound (US) for diagnosis of splenic lymphoma involvement. Methods: From 04/2005 to 10/2008 n = 250 lymphoma patients were investigated by standard B-mode US. A homogeneous splenic echotexture was found in 199 patients (79%). To clarify the benefit of CEUS in this group a pilot series was performed with 16 of the 199 lymphoma patients. All patients with an abnormal splenic echotexture on standard B-Mode US (n = 51) including focal hypoechoic splenic lesions (n = 41) and an inhomogeneous splenic texture (n = 10) were studied by CEUS. CEUS data were retrospectively evaluated. The diagnoses included indolent lymphoma (n = 27), aggressive lymphoma (n = 14), and Hodgkin's disease (n = 10). Number and size of lesions were determined by B-mode US and CEUS. The visualisation of splenic lymphoma involvement by CEUS in comparison to B-mode US was classified as worse, equal, or better. Results: All patients with a homogeneous spleen on B-mode US (n = 16) had no visible focal lesions on CEUS. Study patients with focal lesions (n = 41) had a hypoechoic (n = 22) or isoechoic (n = 19) enhancement during the arterial phase, and a hypoechoic enhancement during the parenchymal phase (n = 41). The visualisation of focal splenic lymphoma was equal (n = 32), better (n = 6), or worse (n = 3). In all study patients with an inhomogeneous spleen on B-mode US (n = 10) no focal lesions were found by CEUS and the value of CEUS therefore was classified as worse. Conclusion: CEUS has no clear advantage for diagnosis of splenic lymphoma involvement.

  16. Added Value of Contrast-Enhanced Ultrasound on Biopsies of Focal Hepatic Lesions Invisible on Fusion Imaging Guidance.

    Science.gov (United States)

    Kang, Tae Wook; Lee, Min Woo; Song, Kyoung Doo; Kim, Mimi; Kim, Seung Soo; Kim, Seong Hyun; Ha, Sang Yun

    2017-01-01

    To assess whether contrast-enhanced ultrasonography (CEUS) with Sonazoid can improve the lesion conspicuity and feasibility of percutaneous biopsies for focal hepatic lesions invisible on fusion imaging of real-time ultrasonography (US) with computed tomography/magnetic resonance images, and evaluate its impact on clinical decision making. The Institutional Review Board approved this retrospective study. Between June 2013 and January 2015, 711 US-guided percutaneous biopsies were performed for focal hepatic lesions. Biopsies were performed using CEUS for guidance if lesions were invisible on fusion imaging. We retrospectively evaluated the number of target lesions initially invisible on fusion imaging that became visible after applying CEUS, using a 4-point scale. Technical success rates of biopsies were evaluated based on histopathological results. In addition, the occurrence of changes in clinical decision making was assessed. Among 711 patients, 16 patients (2.3%) were included in the study. The median size of target lesions was 1.1 cm (range, 0.5-1.9 cm) in pre-procedural imaging. After CEUS, 15 of 16 (93.8%) focal hepatic lesions were visualized. The conspicuity score was significantly increased after adding CEUS, as compared to that on fusion imaging (p making for 11 of 16 patients (68.8%). The addition of CEUS could improve the conspicuity of focal hepatic lesions invisible on fusion imaging. This dual guidance using CEUS and fusion imaging may affect patient management via changes in clinical decision-making.

  17. A contrast-enhanced ultrasound study of benign and malignant ...

    African Journals Online (AJOL)

    A contrast-enhanced ultrasound study of benign and malignant breast tissue. S Barnard, E Leen, T Cooke, W Angerson. Abstract. Objective. To determine the diagnostic value of haemodynamic contrast-enhanced ultrasound assessment in benign and malignant breast tissue, using histological examination as the reference ...

  18. Clinical value of elasticity imaging and contrast-enhanced ultrasound in the diagnosis of papillary thyroid microcarcinoma.

    Science.gov (United States)

    Li, Fengsheng; Zhang, Jianlei; Wang, Yunmei; Liu, Liwen

    2015-09-01

    The present study aimed to evaluate the value of elasticity imaging and contrast-enhanced ultrasonography (CEUS) in the differential diagnosis of papillary thyroid microcarcinoma (TMC). In total, 73 patients exhibiting a total of 80 small thyroid nodules, which were difficult to diagnose using conventional ultrasonography, underwent elasticity imaging and CEUS. The diagnostic findings were subsequently clarified by intraoperative and pathological examination, and the accuracy of the 2 diagnostic methods was compared. The correct diagnostic rate of CEUS was 85% (68/80 nodules), of which 6 cases of TMC were misdiagnosed as benign lesions and 6 benign nodules were misdiagnosed as TMC. By contrast, the accuracy rate of the elasticity imaging, based on the 5-point diagnostic method, was 92.5% (74/80 nodules), of which 3 cases of TMC were misdiagnosed as benign nodules and 3 benign nodules were misdiagnosed as TMC. Furthermore, elasticity imaging in the diagnosis of TMC was determined to have sensitivity, specificity and accuracy rates of 94.0, 90.0 and 92.5%, respectively, whereas the corresponding rates for CEUS were 88.0, 80.0 and 85.0%, respectively. Thus, ultrasonographic elasticity imaging exhibited significant advantages in the diagnosis of TMC compared with CEUS (Padvantage in the diagnosis of TMC; however, an elasticity score of ≥3 is of high clinical value as a diagnostic criterion for TMC.

  19. Contrast-enhanced ultrasound for extrahepatic lesions: preliminary experience

    Energy Technology Data Exchange (ETDEWEB)

    Thorelius, Lars E-mail: lars@thorelius.com

    2004-06-01

    Ultrasound imaging (US) is a convenient, inexpensive and non-invasive investigation. Its use is limited by low sensitivity in the detection of a number of parenchymal lesions, especially those produced by trauma, such as infarctions. Contrast enhancement with SonoVue{sup [reg]} improves the sensitivity of ultrasound in the detection and characterization of focal liver lesions to such an extent, that it may replace computed tomography (CT) and magnetic resonance imaging (MRI). Preliminary experience suggests that SonoVue-enhanced sonography may be useful in the detection of lesions in which blood flow is severely reduced as compared to surrounding parenchyma, such as infarctions, lacerations, hematomas, necrotic tissue and non-vascular cysts, especially in the spleen, kidney and pancreas. This technique can also rule out occlusion of the superior mesenteric, splenic and portal veins, and dilation of the biliary tree. Clinical trials comparing contrast-enhanced sonography with contrast-enhanced computed tomography are warranted to establish the role of this inexpensive and non-invasive technique in the routine work-up of patients with abdominal trauma or presenting with sudden flank pain.

  20. Added value of contrast-enhanced ultrasound on biopsies of focal hepatic lesions invisible on fusion imaging guidance

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Tae Wook; Lee, Min Woo; Song, Kyoung Doo; Kim, Mimi; Kim, Seung Soo; Kim, Seong Hyun; Ha, Sang Yun [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2017-01-15

    To assess whether contrast-enhanced ultrasonography (CEUS) with Sonazoid can improve the lesion conspicuity and feasibility of percutaneous biopsies for focal hepatic lesions invisible on fusion imaging of real-time ultrasonography (US) with computed tomography/magnetic resonance images, and evaluate its impact on clinical decision making. The Institutional Review Board approved this retrospective study. Between June 2013 and January 2015, 711 US-guided percutaneous biopsies were performed for focal hepatic lesions. Biopsies were performed using CEUS for guidance if lesions were invisible on fusion imaging. We retrospectively evaluated the number of target lesions initially invisible on fusion imaging that became visible after applying CEUS, using a 4-point scale. Technical success rates of biopsies were evaluated based on histopathological results. In addition, the occurrence of changes in clinical decision making was assessed. Among 711 patients, 16 patients (2.3%) were included in the study. The median size of target lesions was 1.1 cm (range, 0.5–1.9 cm) in pre-procedural imaging. After CEUS, 15 of 16 (93.8%) focal hepatic lesions were visualized. The conspicuity score was significantly increased after adding CEUS, as compared to that on fusion imaging (p < 0.001). The technical success rate of biopsy was 87.6% (14/16). After biopsy, there were changes in clinical decision making for 11 of 16 patients (68.8%). The addition of CEUS could improve the conspicuity of focal hepatic lesions invisible on fusion imaging. This dual guidance using CEUS and fusion imaging may affect patient management via changes in clinical decision-making.

  1. Added value of contrast-enhanced ultrasound on biopsies of focal hepatic lesions invisible on fusion imaging guidance

    International Nuclear Information System (INIS)

    Kang, Tae Wook; Lee, Min Woo; Song, Kyoung Doo; Kim, Mimi; Kim, Seung Soo; Kim, Seong Hyun; Ha, Sang Yun

    2017-01-01

    To assess whether contrast-enhanced ultrasonography (CEUS) with Sonazoid can improve the lesion conspicuity and feasibility of percutaneous biopsies for focal hepatic lesions invisible on fusion imaging of real-time ultrasonography (US) with computed tomography/magnetic resonance images, and evaluate its impact on clinical decision making. The Institutional Review Board approved this retrospective study. Between June 2013 and January 2015, 711 US-guided percutaneous biopsies were performed for focal hepatic lesions. Biopsies were performed using CEUS for guidance if lesions were invisible on fusion imaging. We retrospectively evaluated the number of target lesions initially invisible on fusion imaging that became visible after applying CEUS, using a 4-point scale. Technical success rates of biopsies were evaluated based on histopathological results. In addition, the occurrence of changes in clinical decision making was assessed. Among 711 patients, 16 patients (2.3%) were included in the study. The median size of target lesions was 1.1 cm (range, 0.5–1.9 cm) in pre-procedural imaging. After CEUS, 15 of 16 (93.8%) focal hepatic lesions were visualized. The conspicuity score was significantly increased after adding CEUS, as compared to that on fusion imaging (p < 0.001). The technical success rate of biopsy was 87.6% (14/16). After biopsy, there were changes in clinical decision making for 11 of 16 patients (68.8%). The addition of CEUS could improve the conspicuity of focal hepatic lesions invisible on fusion imaging. This dual guidance using CEUS and fusion imaging may affect patient management via changes in clinical decision-making

  2. Contrast enhanced ultrasound in the assessment of urogenital pathology

    Directory of Open Access Journals (Sweden)

    Libero Barozzi

    2014-12-01

    Full Text Available Contrast enhanced ultrasound (CEUS is an innovative technique that employs microbubble contrast agents to demonstrate parenchymal perfusion. Although initial clinical application was focused on the liver pathology, a wide variety of clinical conditions can be assessed now with CEUS. CEUS is a well-tolerated technique and is acquiring an increasing role in the assessment of renal pathology because contrast agents are not excreted by the kidney and do not affect the renal function. CEUS demonstrated an accuracy similar to contrast enhanced multi-detector computed tomography (CEMDCT in detecting focal lesions, with the advantage of the real-time assessment of microvascular perfusion by using time-intensity curves. The aim of this paper is to review the main indications of CEUS in the assessment of renal and urogenital pathology. Imaging examples are presented and described. Advantages and limitations of CEUS with reference to conventional US and CE-MDCT are discussed.

  3. Focused Ultrasound-Induced Blood-Brain Barrier Opening: Association with Mechanical Index and Cavitation Index Analyzed by Dynamic Contrast-Enhanced Magnetic-Resonance Imaging.

    Science.gov (United States)

    Chu, Po-Chun; Chai, Wen-Yen; Tsai, Chih-Hung; Kang, Shih-Tsung; Yeh, Chih-Kuang; Liu, Hao-Li

    2016-09-15

    Focused ultrasound (FUS) with microbubbles can temporally open the blood-brain barrier (BBB), and the cavitation activities of microbubbles play a key role in the BBB-opening process. Previous attempts used contrast-enhanced magnetic resonance imaging (CE-MRI) to correlate the mechanical index (MI) with the scale of BBB-opening, but MI only partially gauged acoustic activities, and CE-MRI did not fully explore correlations of pharmacodynamic/pharmacokinetic behaviors. Recently, the cavitation index (CI) has been derived to serve as an indicator of microbubble-ultrasound stable cavitation, and may also serve as a valid indicator to gauge the level of FUS-induced BBB opening. This study investigates the feasibility of gauging FUS-induced BBB opened level via the two indexes, MI and CI, through dynamic contrast-enhanced (DCE)-MRI analysis as well as passive cavitation detection (PCD) analysis. Pharmacodynamic/pharmacokinetic parameters derived from DCE-MRI were characterized to identify the scale of FUS-induced BBB opening. Our results demonstrated that DCE-MRI can successfully access pharmacodynamic/pharmacokinetic BBB-opened behavior, and was highly correlated both with MI and CI, implying the feasibility in using these two indices to gauge the scale of FUS-induced BBB opening. The proposed finding may facilitate the design toward using focused ultrasound as a safe and reliable noninvasive CNS drug delivery.

  4. Value of contrast-enhanced ultrasound in rheumatoid arthritis

    Energy Technology Data Exchange (ETDEWEB)

    Zordo, Tobias de; Mlekusch, Sabine P.; Feuchtner, Gudrun M. [Department of Radiology II, Medical University Innsbruck, Anichstrasse 35, 6020 Innsbruck (Austria); Mur, Erich [Department of Internal Medicine, Medical University Innsbruck, Anichstrasse 35, 6020 Innsbruck (Austria); Schirmer, Michael [Department of Internal Medicine, Hospital of the Elisabethines Klagenfurt, Voelkermarkter Strasse 15-19, 9020 Klagenfurt (Austria); Klauser, Andrea S. [Department of Radiology II, Medical University Innsbruck, Anichstrasse 35, 6020 Innsbruck (Austria)], E-mail: andrea.klauser@i-med.ac.at

    2007-11-15

    The purpose of this review is to describe the spectrum of sonographic findings in rheumatic diseases with respect to the diagnostic potential using US contrast media which prove activity or inactivity in synovial tissue where new treatment regimes target. Synovial activity can be found in non-erosive and erosive forms of primary and secondary osteoarthritis, and in inflammatory forms of joint diseases like rheumatoid arthritis and peripheral manifestations of spondyloarthritis including, ankylosing spondylitis, Reiter's syndrome, psoriatic arthritis and enteropathic arthritis. It can also be present in metabolic and endocrine forms of arthritis, in connective tissue arthropathies like systemic lupus erythematosus or scleroderma and in infectious arthritis. Ultrasound should be used as first-line imaging modality in suspected early cases of RA and other forms of arthritis, whereas contrast-enhanced ultrasound (CEUS) can further enable for sensitive assessment of vascularity which correlates with disease activity.

  5. Value of contrast-enhanced ultrasound in rheumatoid arthritis

    International Nuclear Information System (INIS)

    Zordo, Tobias de; Mlekusch, Sabine P.; Feuchtner, Gudrun M.; Mur, Erich; Schirmer, Michael; Klauser, Andrea S.

    2007-01-01

    The purpose of this review is to describe the spectrum of sonographic findings in rheumatic diseases with respect to the diagnostic potential using US contrast media which prove activity or inactivity in synovial tissue where new treatment regimes target. Synovial activity can be found in non-erosive and erosive forms of primary and secondary osteoarthritis, and in inflammatory forms of joint diseases like rheumatoid arthritis and peripheral manifestations of spondyloarthritis including, ankylosing spondylitis, Reiter's syndrome, psoriatic arthritis and enteropathic arthritis. It can also be present in metabolic and endocrine forms of arthritis, in connective tissue arthropathies like systemic lupus erythematosus or scleroderma and in infectious arthritis. Ultrasound should be used as first-line imaging modality in suspected early cases of RA and other forms of arthritis, whereas contrast-enhanced ultrasound (CEUS) can further enable for sensitive assessment of vascularity which correlates with disease activity

  6. Correction of Non-Linear Propagation Artifact in Contrast-Enhanced Ultrasound Imaging of Carotid Arteries: Methods and in Vitro Evaluation.

    Science.gov (United States)

    Yildiz, Yesna O; Eckersley, Robert J; Senior, Roxy; Lim, Adrian K P; Cosgrove, David; Tang, Meng-Xing

    2015-07-01

    Non-linear propagation of ultrasound creates artifacts in contrast-enhanced ultrasound images that significantly affect both qualitative and quantitative assessments of tissue perfusion. This article describes the development and evaluation of a new algorithm to correct for this artifact. The correction is a post-processing method that estimates and removes non-linear artifact in the contrast-specific image using the simultaneously acquired B-mode image data. The method is evaluated on carotid artery flow phantoms with large and small vessels containing microbubbles of various concentrations at different acoustic pressures. The algorithm significantly reduces non-linear artifacts while maintaining the contrast signal from bubbles to increase the contrast-to-tissue ratio by up to 11 dB. Contrast signal from a small vessel 600 μm in diameter buried in tissue artifacts before correction was recovered after the correction. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  7. Contrast-enhanced ultrasound imaging and in vivo circulatory kinetics with low-boiling-point nanoscale phase-change perfluorocarbon agents.

    Science.gov (United States)

    Sheeran, Paul S; Rojas, Juan D; Puett, Connor; Hjelmquist, Jordan; Arena, Christopher B; Dayton, Paul A

    2015-03-01

    Many studies have explored phase-change contrast agents (PCCAs) that can be vaporized by an ultrasonic pulse to form microbubbles for ultrasound imaging and therapy. However, few investigations have been published on the utility and characteristics of PCCAs as contrast agents in vivo. In this study, we examine the properties of low-boiling-point nanoscale PCCAs evaluated in vivo and compare data with those for conventional microbubbles with respect to contrast generation and circulation properties. To do this, we develop a custom pulse sequence to vaporize and image PCCAs using the Verasonics research platform and a clinical array transducer. Results indicate that droplets can produce contrast enhancement similar to that of microbubbles (7.29 to 18.24 dB over baseline, depending on formulation) and can be designed to circulate for as much as 3.3 times longer than microbubbles. This study also reports for the first time the ability to capture contrast washout kinetics of the target organ as a measure of vascular perfusion. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  8. Real-time 3-dimensional contrast-enhanced ultrasound in detecting hemorrhage of blunt renal trauma.

    Science.gov (United States)

    Xu, Rui-Xue; Li, Ye-Kuo; Li, Ting; Wang, Sha-Sha; Yuan, Gui-Zhong; Zhou, Qun-Fang; Zheng, Hai-Rong; Yan, Fei

    2013-10-01

    The objective of this study is to evaluate the diagnostic value of real-time 3-dimensional contrast-enhanced ultrasound in the hemorrhage of blunt renal trauma. Eighteen healthy New Zealand white rabbits were randomly divided into 3 groups. Blunt renal trauma was performed on each group by using minitype striker. Ultrasonography, color Doppler flow imaging, and contrast-enhanced 2-dimensional and real-time 3-dimensional ultrasound were applied before and after the strike. The time to shock and blood pressure were subjected to statistical analysis. Then, a comparative study of ultrasound and pathology was carried out. All the struck kidneys were traumatic. In the ultrasonography, free fluid was found under the renal capsule. In the color Doppler flow imaging, active hemorrhage was not identified. In 2-dimensional contrast-enhanced ultrasound, active hemorrhage of the damaged kidney was characterized. Real-time 3-dimensional contrast-enhanced ultrasound showed a real-time and stereoscopic ongoing bleeding of the injured kidney. The wider the hemorrhage area in 4-dimensional contrast-enhanced ultrasound was, the faster the blood pressure decreased. Real-time 3-dimensional contrast-enhanced ultrasound is a promising noninvasive tool for stereoscopically and vividly detecting ongoing hemorrhage of blunt renal trauma in real time. © 2013.

  9. Reproducibility of contrast-enhanced transrectal ultrasound of the prostate

    NARCIS (Netherlands)

    Sedelaar, J. P.; Goossen, T. E.; Wijkstra, H.; de la Rosette, J. J.

    2001-01-01

    Transrectal three-dimensional (3-D) contrast-enhanced power Doppler ultrasound (US) is a novel technique for studying possible prostate malignancy. Before studies can be performed to investigate the clinical validity of the technique, reproducibility of the contrast US studies must be proven.

  10. Sonographic patterns of renal lymphoma in B-mode imaging and in contrast-enhanced ultrasound (CEUS)—A retrospective evaluation

    International Nuclear Information System (INIS)

    Trenker, C.; Neesse, A.; Görg, C.

    2015-01-01

    Introduction: Retrospective analysis of sonographic patterns of renal lymphoma in B-mode imaging and contrast-enhanced ultrasound (CEUS). Patients/methods: From January 2000 to June 2014, 27 patients with clinical or histologically confirmed renal lymphoma were examined with B-mode imaging, followed by CEUS in 8 cases. Results: In B-mode imaging renal lymphoma were hypoechoic in all 27 cases (100%). 9 patients (33.3%) had a bilateral, 18 (66.7%) patients had an unilateral lymphoma infiltration of the kidneys. 8 (29.6%) cases of small nodular, 5 (18.5%) cases of large nodular and 6 (22.2%) cases of perirenal lymphoma infiltration of the kidney were observed in B-mode imaging. Bulky-formation of renal lymphoma was detected in 6 (22.2%) patients and 2 (7.4%) patients had a diffuse lymphoma infiltration of the kidneys. In CEUS an arterial isoechoic enhancement was observed in 5 (62.5%)- and, an arterial hypoechoic enhancement was observed in 3 (37.5%) cases of renal lymphoma. A hypoechoic enhancement in the parenchymal phase was observed in 8 (100%) cases of renal lymphoma infiltration. Conclusion: In B-mode-imaging, nodular lymphoma infiltration of the kidneys is the most common of all renal lymphoma patterns in B-mode imaging. In CEUS, renal lymphoma presented an arterial iso- or hypoechoic enhancement, followed by a hypoechoic enhancement in the parenchymal phase. In regard to the differentiation of renal lymphoma to benign lesions of the kidney, CEUS may be helpful. However, the differentiation of renal lymphoma from other malignant lesions of the kidney like renal cell carcinoma is not feasible by CEUS

  11. Contrast enhancement of mail piece images

    Science.gov (United States)

    Shin, Yong-Chul; Sridhar, Ramalingam; Demjanenko, Victor; Palumbo, Paul W.; Hull, Jonathan J.

    1992-08-01

    A New approach to contrast enhancement of mail piece images is presented. The contrast enhancement is used as a preprocessing step in the real-time address block location (RT-ABL) system. The RT-ABL system processes a stream of mail piece images and locates destination address blocks. Most of the mail pieces (classified into letters) show high contrast between background and foreground. As an extreme case, however, the seasonal greeting cards usually use colored envelopes which results in reduced contrast osured by an error rate by using a linear distributed associative memory (DAM). The DAM is trained to recognize the spectra of three classes of images: with high, medium, and low OCR error rates. The DAM is not forced to make a classification every time. It is allowed to reject as unknown a spectrum presented that does not closely resemble any that has been stored in the DAM. The DAM was fairly accurate with noisy images but conservative (i.e., rejected several text images as unknowns) when there was little ground and foreground degradations without affecting the nondegraded images. This approach provides local enhancement which adapts to local features. In order to simplify the computation of A and (sigma) , dynamic programming technique is used. Implementation details, performance, and the results on test images are presented in this paper.

  12. A two-stage multi-view learning framework based computer-aided diagnosis of liver tumors with contrast enhanced ultrasound images.

    Science.gov (United States)

    Guo, Le-Hang; Wang, Dan; Qian, Yi-Yi; Zheng, Xiao; Zhao, Chong-Ke; Li, Xiao-Long; Bo, Xiao-Wan; Yue, Wen-Wen; Zhang, Qi; Shi, Jun; Xu, Hui-Xiong

    2018-04-04

    With the fast development of artificial intelligence techniques, we proposed a novel two-stage multi-view learning framework for the contrast-enhanced ultrasound (CEUS) based computer-aided diagnosis for liver tumors, which adopted only three typical CEUS images selected from the arterial phase, portal venous phase and late phase. In the first stage, the deep canonical correlation analysis (DCCA) was performed on three image pairs between the arterial and portal venous phases, arterial and delayed phases, and portal venous and delayed phases respectively, which then generated total six-view features. While in the second stage, these multi-view features were then fed to a multiple kernel learning (MKL) based classifier to further promote the diagnosis result. Two MKL classification algorithms were evaluated in this MKL-based classification framework. We evaluated proposed DCCA-MKL framework on 93 lesions (47 malignant cancers vs. 46 benign tumors). The proposed DCCA-MKL framework achieved the mean classification accuracy, sensitivity, specificity, Youden index, false positive rate, and false negative rate of 90.41 ± 5.80%, 93.56 ± 5.90%, 86.89 ± 9.38%, 79.44 ± 11.83%, 13.11 ± 9.38% and 6.44 ± 5.90%, respectively, by soft margin MKL classifier. The experimental results indicate that the proposed DCCA-MKL framework achieves best performance for discriminating benign liver tumors from malignant liver cancers. Moreover, it is also proved that the three-phase CEUS image based CAD is feasible for liver tumors with the proposed DCCA-MKL framework.

  13. Enhancement pattern of hilar cholangiocarcinoma: Contrast-enhanced ultrasound versus contrast-enhanced computed tomography

    International Nuclear Information System (INIS)

    Xu Huixiong; Chen Lida; Xie Xiaoyan; Xie Xiaohua; Xu Zuofeng; Liu Guangjian; Lin Manxia; Wang Zhu; Lu Mingde

    2010-01-01

    Objective: To compare the enhancement pattern of hilar cholangiocarcinoma on contrast-enhanced ultrasound (CEUS) with that on contrast-enhanced computed tomography (CECT). Methods: Thirty-two consecutive patients with pathologically proven hilar cholangiocarcinomas were evaluated by both low mechanical index CEUS and CECT. The enhancement feature of the tumor, portal vein infiltration, and lesion conspicuity on them was investigated. Results: In the arterial phase, the numbers of the lesions showing hyperenhancement, isoenhancement, and hypoenhancement, were 14 (43.8%), 14 (43.8%), and 4 (12.6%), on CEUS, and 12 (37.5%), 9 (28.1%), and 11 (34.4%), on CECT (P = 0.162). In portal phase, the numbers of the lesions showing hypoenhancement, isoenhancement, and hyperenhancement were 30 (93.8%), 1 (3.1%), and 1 (3.1%), on CEUS, and 23 (71.9%), 8 (25.0%), and 1 (3.1%), on CECT (P = 0.046). The detection rates for portal vein infiltration were 84.2% (16/19) for baseline ultrasound, 89.5% (17/19) for CEUS, and 78.9% (15/19) for CECT (all P > 0.05 between every two groups). CEUS significantly improved the lesion conspicuity in comparison with CECT. CEUS and CECT made correct diagnoses in 30 (93.8%) and 25 (78.1%) lesions prior to pathological examination (P = 0.125). Conclusion: The enhancement pattern of hilar cholangiocarcinoma on CEUS was similar with that on CECT in arterial phase, whereas in portal phase hilar cholangiocarcinoma shows hypoenhancement more likely on CEUS. CEUS and CECT lead to similar results in evaluating portal vein infiltration and diagnosis of this entity.

  14. Enhancement pattern of hilar cholangiocarcinoma: Contrast-enhanced ultrasound versus contrast-enhanced computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Xu Huixiong, E-mail: xuhuixiong@hotmail.co [Department of Medical Ultrasonics, The First Affiliated Hospital, Institute of Diagnostic and Interventional Ultrasound, Sun Yat-Sen University, 58 Zhongshan Road 2, Guangzhou 510080 (China); Chen Lida; Xie Xiaoyan; Xie Xiaohua; Xu Zuofeng; Liu Guangjian; Lin Manxia; Wang Zhu [Department of Medical Ultrasonics, The First Affiliated Hospital, Institute of Diagnostic and Interventional Ultrasound, Sun Yat-Sen University, 58 Zhongshan Road 2, Guangzhou 510080 (China); Lu Mingde, E-mail: lumd@21cn.co [Department of Hepatobiliary Surgery, First Affiliated Hospital, Sun Yat-Sen University, 58 Zhongshan Road 2, Guangzhou 510080 (China)

    2010-08-15

    Objective: To compare the enhancement pattern of hilar cholangiocarcinoma on contrast-enhanced ultrasound (CEUS) with that on contrast-enhanced computed tomography (CECT). Methods: Thirty-two consecutive patients with pathologically proven hilar cholangiocarcinomas were evaluated by both low mechanical index CEUS and CECT. The enhancement feature of the tumor, portal vein infiltration, and lesion conspicuity on them was investigated. Results: In the arterial phase, the numbers of the lesions showing hyperenhancement, isoenhancement, and hypoenhancement, were 14 (43.8%), 14 (43.8%), and 4 (12.6%), on CEUS, and 12 (37.5%), 9 (28.1%), and 11 (34.4%), on CECT (P = 0.162). In portal phase, the numbers of the lesions showing hypoenhancement, isoenhancement, and hyperenhancement were 30 (93.8%), 1 (3.1%), and 1 (3.1%), on CEUS, and 23 (71.9%), 8 (25.0%), and 1 (3.1%), on CECT (P = 0.046). The detection rates for portal vein infiltration were 84.2% (16/19) for baseline ultrasound, 89.5% (17/19) for CEUS, and 78.9% (15/19) for CECT (all P > 0.05 between every two groups). CEUS significantly improved the lesion conspicuity in comparison with CECT. CEUS and CECT made correct diagnoses in 30 (93.8%) and 25 (78.1%) lesions prior to pathological examination (P = 0.125). Conclusion: The enhancement pattern of hilar cholangiocarcinoma on CEUS was similar with that on CECT in arterial phase, whereas in portal phase hilar cholangiocarcinoma shows hypoenhancement more likely on CEUS. CEUS and CECT lead to similar results in evaluating portal vein infiltration and diagnosis of this entity.

  15. Contrast-enhanced Ultrasound for Non-tumor Liver Diseases

    Directory of Open Access Journals (Sweden)

    H Maruyama

    2012-03-01

    Full Text Available Contrast-enhanced ultrasound (CEUS is a simple, safe and reliable technique for the clinical management of patients with various liver diseases. Although the major target of the technique may be focal hepatic lesions, it is also effective for the diagnosis of non-tumor liver diseases, such as grading hepatic fibrosis, characterization of chronic liver diseases and diagnosis of portal vein thrombosis. This review article aimed to overview the recent application of CEUS in the assessment of non-tumor liver diseases. Keywords: Cirrhosis, contrast agent, fibrosis, idiopathic portal hypertension, microbubble, portal vein thrombosis, ultrasound.

  16. The role of contrast-enhanced ultrasound in risk assessment of carotid atheroma

    Directory of Open Access Journals (Sweden)

    Silviu Stanciu

    2016-07-01

    Full Text Available Background and objective: Contrast-enhanced ultrasound, used to assess atherosclerotic carotid plaques, improves visualization of vessel wall irregularities and depicts intraplaque neovascularization. This article illustrates the use of contrast-enhanced ultrasound in the risk assessment of carotid atherosclerotic lesions, especially in challenging plaques evaluation. Materials and methods: For 23 patients with difficult duplex ultrasound examination due to carotid tortuosity or calcifications we assessed plaque morphology (contour, echogenicity and stenosis degree using contrast substance (Sonovue, Braco with dedicated vascular low mechanical index CPC software. Conclusion: Contrast-enhanced ultrasound is a new, noninvasive, and safe procedure for imaging carotid atherosclerotic lesions. It is a valuable tool for evaluating the vulnerable plaque at risk for rupture and for the diagnostic of the development and severity of systemic atherosclerotic disease

  17. Intraoperative Cerebral Glioma Characterization with Contrast Enhanced Ultrasound

    Directory of Open Access Journals (Sweden)

    Francesco Prada

    2014-01-01

    Full Text Available Background. Contrast enhanced ultrasound (CEUS is a dynamic and continuous modality providing real-time view of vascularization and flow distribution patterns of different organs and tumors. Nevertheless its intraoperative use for brain tumors visualization has been performed few times, and a thorough characterization of cerebral glioma had never been performed before. Aim. To perform the first characterization of cerebral glioma using CEUS and to possibly achieve an intraoperative differentiation of different gliomas. Methods. We performed CEUS in an off-label setting in 69 patients undergoing surgery for cerebral glioma. An intraoperative qualitative analysis was performed comparing iCEUS with B-mode imaging. A postprocedural semiquantitative analysis was then performed for each case, according to EFSUMB criteria. Results were related to histopathology. Results. We observed different CE patterns: LGG show a mild, dotted CE with diffuse appearance and slower, delayed arterial and venous phase. HGG have a high CE with a more nodular, nonhomogeneous appearance and fast perfusion patterns. Conclusion. Our study characterizes for the first time human brain glioma with CEUS, providing further insight regarding these tumors’ biology. CEUS is a fast, safe, dynamic, real-time, and economic tool that might be helpful during surgery in differentiating malignant and benign gliomas and refining surgical strategy.

  18. Usefulness of combining gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging and contrast-enhanced ultrasound for diagnosing the macroscopic classification of small hepatocellular carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, Tomoki; Aikata, Hiroshi; Hatooka, Masahiro; Morio, Kei; Morio, Reona; Kan, Hiromi; Fujino, Hatsue; Fukuhara, Takayuki; Masaki, Keiichi; Ohno, Atsushi; Naeshiro, Noriaki; Nakahara, Takashi; Honda, Yohji; Murakami, Eisuke; Kawaoka, Tomokazu; Tsuge, Masataka; Hiramatsu, Akira; Imamura, Michio; Kawakami, Yoshiiku; Hyogo, Hideyuki; Takahashi, Shoichi [Hiroshima University Hospital, Department of Gastroenterology and Metabolism, Hiroshima (Japan); Chayama, Kazuaki [Hiroshima University Hospital, Department of Gastroenterology and Metabolism, Hiroshima (Japan); Hiroshima University, Liver Research Project Center, Hiroshima (Japan)

    2015-11-15

    Non-simple nodules in hepatocellular carcinoma (HCC) correlate with poor prognosis. Therefore, we examined the diagnostic ability of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging (EOB-MRI) and contrast-enhanced ultrasound (CEUS) for diagnosing the macroscopic classification of small HCCs. A total of 85 surgically resected nodules (≤30 mm) were analyzed. HCCs were pathologically classified as simple nodular (SN) and non-SN. By evaluating hepatobiliary phase (HBP) of EOB-MRI and Kupffer phase of CEUS, the diagnostic abilities of both modalities to correctly distinguish between SN and non-SN were compared. Forty-six nodules were diagnosed as SN and the remaining 39 nodules as non-SN. The area under the ROC curve (AUROCs, 95 % confidence interval) for the diagnosis of non-SN were EOB-MRI, 0.786 (0.682-0.890): CEUS, 0.784 (0.679-0.889), in combination, 0.876 (0.792-0.959). The sensitivity, specificity, and accuracy were 64.1 %, 95.7 %, and 81.2 % in EOB-MRI, 56.4 %, 97.8 %, and 78.8 % in CEUS, and 84.6 %, 95.7 %, and 90.6 % in combination, respectively. High diagnostic ability was obtained when diagnosed in both modalities combined. The sensitivity was especially statistically significant compared to CEUS. Combined diagnosis by EOB-MRI and CEUS can provide high-quality imaging assessment for determining non-SN in small HCCs. (orig.)

  19. Usefulness of combining gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging and contrast-enhanced ultrasound for diagnosing the macroscopic classification of small hepatocellular carcinoma.

    Science.gov (United States)

    Kobayashi, Tomoki; Aikata, Hiroshi; Hatooka, Masahiro; Morio, Kei; Morio, Reona; Kan, Hiromi; Fujino, Hatsue; Fukuhara, Takayuki; Masaki, Keiichi; Ohno, Atsushi; Naeshiro, Noriaki; Nakahara, Takashi; Honda, Yohji; Murakami, Eisuke; Kawaoka, Tomokazu; Tsuge, Masataka; Hiramatsu, Akira; Imamura, Michio; Kawakami, Yoshiiku; Hyogo, Hideyuki; Takahashi, Shoichi; Chayama, Kazuaki

    2015-11-01

    Non-simple nodules in hepatocellular carcinoma (HCC) correlate with poor prognosis. Therefore, we examined the diagnostic ability of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging (EOB-MRI) and contrast-enhanced ultrasound (CEUS) for diagnosing the macroscopic classification of small HCCs. A total of 85 surgically resected nodules (≤30 mm) were analyzed. HCCs were pathologically classified as simple nodular (SN) and non-SN. By evaluating hepatobiliary phase (HBP) of EOB-MRI and Kupffer phase of CEUS, the diagnostic abilities of both modalities to correctly distinguish between SN and non-SN were compared. Forty-six nodules were diagnosed as SN and the remaining 39 nodules as non-SN. The area under the ROC curve (AUROCs, 95% confidence interval) for the diagnosis of non-SN were EOB-MRI, 0.786 (0.682-0.890): CEUS, 0.784 (0.679-0.889), in combination, 0.876 (0.792-0.959). The sensitivity, specificity, and accuracy were 64.1%, 95.7%, and 81.2% in EOB-MRI, 56.4%, 97.8%, and 78.8% in CEUS, and 84.6%, 95.7%, and 90.6% in combination, respectively. High diagnostic ability was obtained when diagnosed in both modalities combined. The sensitivity was especially statistically significant compared to CEUS. Combined diagnosis by EOB-MRI and CEUS can provide high-quality imaging assessment for determining non-SN in small HCCs. • Non-SN has a higher frequency of MVI and intrahepatic metastasis than SN. • Macroscopic classification is useful to choose the treatment strategy for small HCCs. • Diagnostic ability for macroscopic findings of EOB-MRI and CEUS were statistically equal. • The diagnosis of macroscopic findings by individual modality has limitations. • Combined diagnosis of EOB-MRI and CEUS provides high diagnostic ability.

  20. Evaluation of short-term response of high intensity focused ultrasound ablation for primary hepatic carcinoma: Utility of contrast-enhanced MRI and diffusion-weighted imaging

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Yuanyuan; Zhao Jiannong [Department of Radiology, Second Affiliated Hospital, Chongqing Medical University, No. 74 Linjiang Rd, Yuzhong District, Chongqing 400010 (China); Guo Dajing, E-mail: guodaj@163.com [Department of Radiology, Second Affiliated Hospital, Chongqing Medical University, No. 74 Linjiang Rd, Yuzhong District, Chongqing 400010 (China); Zhong Weijia [Department of Radiology, Second Affiliated Hospital, Chongqing Medical University, No. 74 Linjiang Rd, Yuzhong District, Chongqing 400010 (China); Ran Lifen [Clinical Center for Tumor Therapy, Second Affiliated Hospital, Chongqing Medical University, No. 74 Linjiang Rd, Yuzhong District, Chongqing 400010 (China)

    2011-09-15

    Objective: To explore the significance of contrast-enhanced MRI (CE-MRI) and diffusion-weighted imaging (DWI) in evaluating the short-term response of high intensity focused ultrasound (HIFU) ablation for primary hepatic carcinoma (PHC). Methods: Thirty-nine lesions in the livers of 27 patients were performed HIFU ablation. Conventional MRI sequences, CE-MRI and DWI were performed 1 week before HIFU and 1 week, 3 months after the therapy, respectively. The short-term responses of HIFU for all lesions were evaluated with MRI. Results: 28 of the 39 lesions (28/39, 71.8%) showed complete necrosis with no enhancement 1 week and 3 months after HIFU. The apparent diffusion coefficient (ADC) values 1 week and 3 months after HIFU were significantly higher than those 1 week before treatment (p < 0.05). The tumor recurrence was detected in 7 of the 39 lesions (7/39, 17.9%) which had no significant enhancement 1 week after HIFU. On the 3 months follow-up, focal nodules were found on the inner aspects of the treated areas. The ADC values had no significant difference between 1 week before and after treatment (p > 0.05), however, they were significantly higher 3 months after HIFU (p < 0.05). The tumor residuals were detected in 4 of the 39 lesions (4/39, 10.3%) showing enhancement 1 week after treatment and increased size 3 months after HIFU. The ADC values had no significant difference among 1 week before HIFU, 1 week and 3 months after treatment (p > 0.05). Conclusion: CE-MRI and DWI can be employed to evaluate the short-term response of HIFU ablation for PHC and to guide the patient management.

  1. Sentinel node detection in melanomas using contrast-enhanced ultrasound

    DEFF Research Database (Denmark)

    Nielsen, K. Rue; Klyver, H.; Chakera, A. Hougaard

    2009-01-01

    in humans. PURPOSE: To investigate the possible use of CEUS in detecting SN in patients with malignant melanomas (MM), and to improve the method by using different concentrations of contrast agent and various positions of the extremity. MATERIAL AND METHODS: Ten patients with MM on an extremity and one...... healthy volunteer were included. One milliliter of a contrast agent (Sonovue; Bracco, Milan, Italy) was injected subcutaneously on both sides of the scar from the excised tumor. Contrast-enhanced lymph channels and lymph nodes (LNs) were searched for using low-mechanical-index CEUS and by stimulated...... tissue damage, as the contrast agent was not registered for subcutaneous administration. RESULTS: In one patient, two contrast-enhanced inguinal LNs were visualized by CEUS, corresponding to two inguinal SNs found by scintigraphic imaging. No contrast-enhanced lymph channels or LNs were visualized in any...

  2. Contrast-enhanced ultrasound features of histologically proven focal nodular hyperplasia: diagnostic performance compared with contrast-enhanced CT

    International Nuclear Information System (INIS)

    Wang, Wei; Chen, Li-Da; Liu, Guang-Jian; Xu, Zuo-Feng; Xie, Xiao-Yan; Wang, Yan; Zhou, Lu-Yao; Lu, Ming-De; Shen, Shun-Li

    2013-01-01

    To investigate and compare contrast-enhanced ultrasound (CEUS) in the characterisation of histologically proven focal nodular hyperplasia (FNH) with contrast-enhanced computed tomography (CECT). CEUS was performed in 85 patients with 85 histologically proven FNHs. Enhancement, centrifugal filling, spoke-wheel arteries, feeding artery and central scarring were reviewed and correlated with lesion size or liver background. Independent factors for predicting FNH from other focal liver lesions (FLLs) were evaluated. Forty-seven FLLs with CECT were randomly selected for comparison of diagnostic performance with CEUS. Centrifugal filling was more common (P = 0.002) and the significant predictor (P = 0.003) in FNHs ≤3 cm. Lesion size or liver background has no significant influence on the detection rate of the spoke-wheel arteries and feeding artery (P > 0.05). Central scarring was found in 42.6 % of FNHs ≥3 cm (P = 0.000). The area under the ROC curve, sensitivity and specificity showed no significant differences between CEUS and CECT (P > 0.05), except that the sensitivity of CEUS was better for reader 1 (P = 0.041). CEUS is valuable in characterising centrifugal filling signs or spoke wheels in small FNHs and should be employed as the first-line imaging technique for diagnosis of FNH. (orig.)

  3. Contrast-Enhanced Ultrasound and Near-Infrared Spectroscopy of the Neonatal Bowel: Novel, Bedside, Noninvasive, and Radiation-Free Imaging for Early Detection of Necrotizing Enterocolitis.

    Science.gov (United States)

    Al-Hamad, Suzanne; Hackam, David J; Goldstein, Seth D; Huisman, Thierry A G M; Darge, Kassa; Hwang, Misun

    2018-05-31

    Despite extensive research and improvements in the field of neonatal care, the morbidity and mortality associated with necrotizing enterocolitis (NEC) have remained unchanged over the past three decades. Early detection of ischemia and necrotic bowel is vital in improving morbidity and mortality associated with NEC; however, strategies for predicting and preventing NEC are lacking. Contrast-enhanced ultrasound (CEUS) and near-infrared spectroscopy (NIRS) are novel techniques in pediatrics that have been proven as safe modalities. CEUS has benefits over conventional ultrasound (US) by its improved real-time evaluation of the micro- and macrovascularities of normally and abnormally perfused tissue. US has been implemented as a useful adjunct to X-ray for earlier evaluation of NEC. NIRS is another noninvasive technique that has shown promise in improving early detection of NEC. The purpose of this article is to review the current understanding of changes in bowel perfusion in NEC, discuss the accuracy of abdominal US in detecting NEC, and explain how the use of CEUS and NIRS will enhance the precise and early detection of altered/pathological bowel wall perfusion in the initial development and course of NEC. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  4. The role of contrast-enhanced endoscopic ultrasound in pancreatic adenocarcinoma

    DEFF Research Database (Denmark)

    Saftoiu, Adrian; Vilmann, Peter; Bhutani, Manoop S

    2016-01-01

    contrast agents for early detection, tridimensional and fusion techniques for enhanced staging and resectability assessment but also novel applications of perfusion imaging for monitoring ablative therapy, improved local detection through EUS-guided sampling of portal vein flow or enhanced drug delivery......Contrast-enhanced endoscopic ultrasound (CE-EUS) allows characterization, differentiation, and staging of focal pancreatic masses. The method has a high sensitivity and specificity for the diagnosis of pancreatic adenocarcinoma which is visualized as hypo-enhanced as compared to the rest...... of the parenchyma while chronic pancreatitis and neuroendocrine tumors are generally either iso-enhanced or hyper-enhanced. The development of contrast-enhanced low mechanical index harmonic imaging techniques used in real time during endoscopic ultrasound (EUS) allowed perfusion imaging and the quantification...

  5. Evaluation of the diagnosis on staging of the bladder cancers by contrast-enhanced ultrasound

    International Nuclear Information System (INIS)

    Gao Yong; Xu Haiyan; Huan Haiming; Chen Yane

    2010-01-01

    Objective: To study the value of the staging of the bladder cancers with the contrast-enhanced ultrasound. Methods: After rapid injection of the contrast agent SonoVue through the elbow vein, the staging of images was completed in 18 cases of bladder cancer. Results: The results of contrast-enhanced ultrasound were compared with post-operative pathological analysis, the rate of accuracy of diagnosis on T1, T2, T3 and T4 stage was 100%, 80%, 83% and 100% respectively. The accuracy made by new methods higher than those of other imaging examinations in T1 stage; the other stages were similar to those of other imaging examinations. Conclusion: The evaluation of Contrast-enhanced ultrasound on the staging of the bladder cancer is higher than that of the conventional ultrasound examination, while the observation of blood flow in the tumor can make accurate diagnosis and differential diagnosis, this method can be complement each other with CT and MRI to improve the rate of accuracy on the staging of bladder cancer. (authors)

  6. MRI and contrast-enhanced ultrasound imaging for evaluation of focal irreversible electroporation treatment: results from a phase I-II study in patients undergoing IRE followed by radical prostatectomy

    International Nuclear Information System (INIS)

    Bos, Willemien van den; Bruin, D.M. de; Randen, A. van; Engelbrecht, M.R.W.; Postema, A.W.; Muller, B.G.; Zondervan, P.J.; Laguna Pes, M.P.; Reijke, T.M. de; Rosette, J.J.M.C.H. de la; Varkarakis, I.M.; Skolarikos, A.; Savci-Heijink, C.D.; Jurhill, R.R.; Wijkstra, H.

    2016-01-01

    Irreversible electroporation (IRE) is an ablative therapy with a low side-effect profile in prostate cancer. The objective was: 1) To compare the volumetric IRE ablation zone on grey-scale transrectal ultrasound (TRUS), contrast-enhanced ultrasound (CEUS) and multiparametric MRI (mpMRI) with histopathology findings; 2) To determine a reliable imaging modality to visualize the IRE ablation effects accurately. A prospective phase I-II study was performed in 16 patients scheduled for radical prostatectomy (RP). IRE of the prostate was performed 4 weeks before RP. Prior to, and 4 weeks after the IRE treatment, imaging was performed by TRUS, CEUS, and mpMRI. 3D-analysis of the ablation volumes on imaging and on H and E-stained whole-mount sections was performed. The volumes were compared and the correlation was calculated. Evaluation of the imaging demonstrated that with T2-weighted MRI, dynamic contrast enhanced (DCE) MRI, and CEUS, effects of IRE are visible. T2MRI and CEUS closely match the volumes on histopathology (Pearson correlation r = 0.88 resp. 0.80). However, IRE is not visible with TRUS. mpMRI and CEUS are appropriate for assessing IRE effects and are the most feasible imaging modalities to visualize IRE ablation zone. The imaging is concordant with results of histopathological examination. (orig.)

  7. Contrast Enhanced Ultrasound of the Kidneys: What Is It Capable of?

    Directory of Open Access Journals (Sweden)

    Demosthenes D. Cokkinos

    2013-01-01

    Full Text Available One of the many imaging uses of contrast enhanced ultrasound (CEUS is studying a wide variety of kidney pathology, due to its ability to detect microvascular blood flow in real time without affecting renal function. CEUS enables dynamic assessment and quantification of microvascularisation up to capillary perfusion. The objective of this paper is to briefly refresh basic knowledge of ultrasound (US contrast agents’ physical properties, to study technical details of CEUS scanning in the kidneys, and to review the commonest renal indications for CEUS, with imaging examples in comparison to baseline unenhanced US and computed tomography when performed. Safety matters and limitations of CEUS of the kidneys are also discussed.

  8. Feasibility of contrast-enhanced ultrasound-guided biopsy of sentinel lymph nodes in dogs.

    Science.gov (United States)

    Gelb, Hylton R; Freeman, Lynetta J; Rohleder, Jacob J; Snyder, Paul W

    2010-01-01

    Our goal was to develop and validate a technique to identify the sentinel lymph nodes of the mammary glands of healthy dogs with contrast-enhanced ultrasound, and evaluate the feasibility of obtaining representative samples of a sentinel lymph node under ultrasound guidance using a new biopsy device. Three healthy intact female adult hounds were anesthetized and each received an injection of octafluoropropane-filled lipid microspheres and a separate subcutaneous injection of methylene blue dye around a mammary gland. Ultrasound was then used to follow the contrast agent through the lymphatic channel to the sentinel lymph node. Lymph node biopsy was performed under ultrasound guidance, followed by an excisional biopsy of the lymph nodes and a regional mastectomy procedure. Excised tissues were submitted for histopathologic examination and evaluated as to whether they were representative of the node. The ultrasound contrast agent was easily visualized with ultrasound leading up to the sentinel lymph nodes. Eight normal lymph nodes (two inguinal, one axillary in two dogs; two inguinal in one dog) were identified and biopsied. Lymphoid tissue was obtained from all biopsy specimens. Samples from four of eight lymph nodes contained both cortical and medullary lymphoid tissue. Contrast-enhanced ultrasound can be successfully used to image and guide minimally invasive biopsy of the normal sentinel lymph nodes draining the mammary glands in healthy dogs. Further work is needed to evaluate whether this technique may be applicable in patients with breast cancer or other conditions warranting evaluation of sentinel lymph nodes in animals.

  9. Vascular Structure Identification in Intraoperative 3D Contrast-Enhanced Ultrasound Data

    Directory of Open Access Journals (Sweden)

    Elisee Ilunga-Mbuyamba

    2016-04-01

    Full Text Available In this paper, a method of vascular structure identification in intraoperative 3D Contrast-Enhanced Ultrasound (CEUS data is presented. Ultrasound imaging is commonly used in brain tumor surgery to investigate in real time the current status of cerebral structures. The use of an ultrasound contrast agent enables to highlight tumor tissue, but also surrounding blood vessels. However, these structures can be used as landmarks to estimate and correct the brain shift. This work proposes an alternative method for extracting small vascular segments close to the tumor as landmark. The patient image dataset involved in brain tumor operations includes preoperative contrast T1MR (cT1MR data and 3D intraoperative contrast enhanced ultrasound data acquired before (3D-iCEUS s t a r t and after (3D-iCEUS e n d tumor resection. Based on rigid registration techniques, a preselected vascular segment in cT1MR is searched in 3D-iCEUS s t a r t and 3D-iCEUS e n d data. The method was validated by using three similarity measures (Normalized Gradient Field, Normalized Mutual Information and Normalized Cross Correlation. Tests were performed on data obtained from ten patients overcoming a brain tumor operation and it succeeded in nine cases. Despite the small size of the vascular structures, the artifacts in the ultrasound images and the brain tissue deformations, blood vessels were successfully identified.

  10. Microwave ablation of liver metastases guided by contrast-enhanced ultrasound

    DEFF Research Database (Denmark)

    Lorentzen, T; Skjoldbye, B O; Nolsoe, C P

    2011-01-01

    The aim of our study was to evaluate the efficacy of microwave (MW) ablation of liver metastases guided by B-mode ultrasound (US) and contrast-enhanced US (CEUS).......The aim of our study was to evaluate the efficacy of microwave (MW) ablation of liver metastases guided by B-mode ultrasound (US) and contrast-enhanced US (CEUS)....

  11. Guidelines and good clinical practice recommendations for Contrast Enhanced Ultrasound (CEUS) in the liver - update 2012

    DEFF Research Database (Denmark)

    Claudon, Michel; Dietrich, Christoph F; Choi, Byung Ihn

    2013-01-01

    Initially, a set of guidelines for the use of ultrasound contrast agents was published in 2004 dealing only with liver applications. A second edition of the guidelines in 2008 reflected changes in the available contrast agents and updated the guidelines for the liver, as well as implementing some...... Medizin/European Journal of Ultrasound for EFSUMB). These guidelines and recommendations provide general advice on the use of all currently clinically available ultrasound contrast agents (UCA). They are intended to create standard protocols for the use and administration of UCA in liver applications...... non-liver applications. Time has moved on, and the need for international guidelines on the use of CEUS in the liver has become apparent. The present document describes the third iteration of recommendations for the hepatic use of contrast enhanced ultrasound (CEUS) using contrast specific imaging...

  12. Contrast-enhanced ultrasound features of hepatocellular carcinoma not detected during the screening procedure.

    Science.gov (United States)

    Dong, Yi; Wang, Wen-Ping; Mao, Feng; Dietrich, Christoph

    2017-08-01

    Aim  The aim of this retrospective study is to report on the characteristics of contrast-enhanced ultrasound (CEUS) of primarily not detected hepatocellular carcinoma (HCC) during the screening procedure of patients at risk. Methods  Sixty-four patients with a finally solitary and histologically proven HCC not detected HCC during the screening procedure were retrospectively analyzed. Most of HCC lesions (90.6 %, 58/64) measured < 20 mm in diameter. All HCC lesions were not detected during the initial screening procedure but suspected using contrast-enhanced magnetic resonance imaging. The final gold standard was biopsy or surgery with histological examination. Results  On CEUS, 62/64 (96.8 %) of HCC were characterized as an obviously hyperenhanced lesion in arterial phase, and 41/64 (64.1 %) of HCC were characterized as hypoenhancing lesions in the portal venous and late phases. During the arterial phase of CEUS, 96.8 % of HCC displayed homogeneous hyperenhancement. Knowing the CEUS and magnetic resonance imaging findings, 45/64 (70.3 %) could have been detected using B-mode ultrasound (BMUS). Conclusion  BMUS as a screening procedure is generally accepted. Contrast-enhanced imaging modalities have improved detection and characterization of HCC. Homogeneous hyperenhancement during the arterial phase and mild washout are indicative for HCC in liver cirrhosis. © Georg Thieme Verlag KG Stuttgart · New York.

  13. Ultrasound contrast-enhanced study as an imaging biomarker for anti-cancer drug treatment: preliminary study with paclitaxel in a xenograft mouse tumor model (secondary publication)

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hak Jong; Hwang, Sung Il; Jung, Hyun Sook; Kang, Mi Ra [Dept. of Radiology, Seoul National University College of Medicine and Seoul National University Bundang Hospital, Seongnam (Korea, Republic of); Byun, Jong Hoe; Kong, Hoon Young [Dept. of Molecular Biology, Dankook University, Cheonan (Korea, Republic of)

    2017-10-15

    The purpose of this study was to assess tumor angiogenesis using contrast-enhanced ultrasonography (CEUS) of human prostate cancer cells (PC3) that were implanted in mice before and after paclitaxel injection. Twelve mice were injected with human PC3. The mice were grouped into two groups; one was the paclitaxel-treated group (n=6) and the other was the control group (n=6). Before administering paclitaxel into the peritoneal cavity, baseline CEUS was performed after the administration of 500 μL (1×108 microbubbles) of contrast agent. The area under the curve (AUC) up to 50 seconds after injection was derived from the time-intensity curves. After injection of paclitaxel or saline, CEUS studies were performed at the 1-week follow-up. Changes in tumor volume and the AUC in both two groups were evaluated. After CEUS, the microvessel density (MVD) was compared between the groups. In the paclitaxel-treated group, the AUC from CEUS showed a significant decrease 1-week after paclitaxel administration (P=0.030), even though the tumor volume showed no significant changes (P=0.116). In the control group, there was no significant decrease of the AUC (P=0.173). Pathologically, there was a significant difference in MVD between both groups (P=0.002). The AUC from the time intensity curve derived from CEUS showed an early change in response to the anti-cancer drug treatment that preceded the change in tumor size. The findings of CEUS could serve as an imaging biomarker for assessing tumor responses to anti-cancer drug treatment.

  14. Screened Poisson Equation for Image Contrast Enhancement

    Directory of Open Access Journals (Sweden)

    Jean-Michel Morel

    2014-03-01

    Full Text Available In this work we propose a discussion and detailed implementation of a very simple gradient domain method that tries to eliminate the effect of nonuniform illumination and at the same time preserves the images details. This model, which to the best of our knowledge has not been explored in spite of its simplicity, acts as a high pass filter. We show that with a single contrast parameter (which keeps the same value in most experiments, the model delivers state of the art results. They compare favorably to results obtained with more complex algorithms. Our algorithm is designed for all kinds of images, but with the special specification of making minimal image detail alteration thanks to a first order fidelity term, instead of the usual zero order term. Experiments on non-uniform medical images and on hazy images illustrate significant perception gain.

  15. Hilar biliary neurofibroma without neurofibromatosis: case report with contrast-enhanced ultrasound findings.

    Science.gov (United States)

    Guo, Huan-Ling; Chen, Li-da; Wang, Zhu; Huang, Yang; Liu, Jin-Ya; Shan, Quan-Yuan; Xie, Xiao-Yan; Lu, Ming-de; Wang, Wei

    2016-10-01

    Solitary neurofibroma located in the hilum of the liver is extremely rare, particularly without neurofibromatosis. We herein report a case of hilar biliary neurofibroma without signs of von Recklinghausen's disease. A 36-year-old man was admitted to our department with progressive jaundice. The case was diagnosed as hilar cholangiocarcinoma based on preoperative imaging. The patient consequently received a Roux-en-Y hepaticojejunostomy and was confirmed with neurofibroma pathologically. This is the first reported imaging finding of hilar biliary neurofibroma using contrast-enhanced ultrasound, emphasizing the differential diagnosis of biliary tumors.

  16. Common and uncommon features of focal splenic lesions on contrast-enhanced ultrasound: a pictorial review

    Energy Technology Data Exchange (ETDEWEB)

    Zavariz, Julia D., E-mail: julia.zavariz@hc.fm.usp.br [Universidade de São Paulo (HC/FMUSP), São Paulo, SP (Brazil). Faculdade de Medicina. Hospital das Clínicas; Konstantatou, Eleni; Deganello Annamaria; Bosanac, Diana; Huang, Dean Y.; Sellars, Maria E.; Sidhu, Paul S. [Department of Radiology, King’s College Hospital, Denmark Hill, London (United Kingdom)

    2017-11-15

    The characterization of focal splenic lesions by ultrasound can be quite challenging. The recent introduction of contrast-enhanced ultrasound (CEUS) has come to play a valuable role in the field of imaging splenic pathologies, offering the possibility of an ionizing radiation-free investigation. Because CEUS has been incorporated into everyday clinical practice, malignant diseases such as focal lymphomatous infiltration, metastatic deposits, benign cysts, traumatic fractures, and hemangiomas can now be accurately depicted and characterized without the need for further imaging. More specifically, splenic traumatic fractures do not require additional imaging by computed tomography (with ionizing radiation exposure) for follow-up, because splenic fractures and their complications are safely imaged with CEUS. In the new era of CEUS, more patients benefit from radiation-free investigation of splenic pathologies with high diagnostic accuracy. (author)

  17. Contrast-enhanced CISS imaging of cerebellopontine angle tumors

    Energy Technology Data Exchange (ETDEWEB)

    Tozaki, Mitsuhiro; Toyoda, Keiko; Hata, Yuichi; Fukuda, Yasushi; Fukuda, Kunihiko [Jikei Univ., Tokyo (Japan). School of Medicine; Katano, Shuichi

    1999-10-01

    Our purpose of this study was to evaluate the clinical usefulness of contrast-enhanced CISS-3DFT MR imaging for the diagnosis of CP angle tumors. CISS-3DFT MR imaging is expected for screening procedure of acoustic schwannoma because of excellent spatial resolution. Recently, we discovered contrast enhancement effect on CISS sequence in spite of heavily T{sub 2}-weighted images. Fourteen patients with CP angle tumors were performed on a 1.0 T MR unit. Transaxial CISS-3DFT MRI was obtained both before and after intravenous injections of Gd-DTPA. Multiplanar reconstructions (MPRs) were performed in all cases. Contrast enhancement effect of CP angle tumors, and the relationship between tumors and the adjacent cranial nerves were evaluated. Contrast enhancement effect of the tumors was present in all cases in spite of heavily T{sub 2}-weighted images of CISS sequences. In the internal auditory canal, relationship between the tumors and the cranial nerves was demonstrated in 6 cases (6/9). In the cerebellopontine cistern, all cases were demonstrated (11/11). Contrast-enhanced CISS-3DFT MR imaging with a good contrast resolution and an excellent spatial resolution is useful for the diagnosis of CP angle tumors. (author)

  18. THE EXPERIENCE OF USING ULTRASOUND WITH CONTRAST ENHANCEMENT IN THE DIAGNOSIS OF CERVICAL CANCER

    Directory of Open Access Journals (Sweden)

    M. A. Chekalova

    2017-01-01

    Full Text Available The purpose of the study was to evaluate the value of contrast-enhanced ultrasound in detecting local spread, regional and distant metastases from cervical cancer. Materials and methods. The findings of contrast-enhanced ultrasound examination of 4 cervical cancer patients (IB1–IVB treated at N.N. Blokhin Russian Cancer Research Center from September to October 2016 were evaluated. The HI VISION Ascendus device was used. Ultrasound patterns in different phases of contrast-enhanced accumulation and excretion were analyzed. Results. Our first experience in using contrast-enhanced ultrasound in the detection of local spread, regional and distant metastases from cervical cancer allowed us to study the structure of the tumor and its spread in greater detail. Conclusion. A small number of observations do not yet allow us to draw serious conclusions about the capabilities of this modern technology. 

  19. Algorithms for contrast enhancement of electronic portal images

    International Nuclear Information System (INIS)

    Díez, S.; Sánchez, S.

    2015-01-01

    An implementation of two new automatized image processing algorithms for contrast enhancement of portal images is presented as suitable tools which facilitate the setup verification and visualization of patients during radiotherapy treatments. In the first algorithm, called Automatic Segmentation and Histogram Stretching (ASHS), the portal image is automatically segmented in two sub-images delimited by the conformed treatment beam: one image consisting of the imaged patient obtained directly from the radiation treatment field, and the second one is composed of the imaged patient outside it. By segmenting the original image, a histogram stretching can be independently performed and improved in both regions. The second algorithm involves a two-step process. In the first step, a Normalization to Local Mean (NLM), an inverse restoration filter is applied by dividing pixel by pixel a portal image by its blurred version. In the second step, named Lineally Combined Local Histogram Equalization (LCLHE), the contrast of the original image is strongly improved by a Local Contrast Enhancement (LCE) algorithm, revealing the anatomical structures of patients. The output image is lineally combined with a portal image of the patient. Finally the output images of the previous algorithms (NLM and LCLHE) are lineally combined, once again, in order to obtain a contrast enhanced image. These two algorithms have been tested on several portal images with great results. - Highlights: • Two Algorithms are implemented to improve the contrast of Electronic Portal Images. • The multi-leaf and conformed beam are automatically segmented into Portal Images. • Hidden anatomical and bony structures in portal images are revealed. • The task related to the patient setup verification is facilitated by the contrast enhancement then achieved.

  20. A Novel Contrast Enhancement Technique on Palm Bone Images

    Directory of Open Access Journals (Sweden)

    Yung-Tsang Chang

    2014-09-01

    Full Text Available Contrast enhancement plays a fundamental role in image processing. Many histogram-based techniques are widely used for contrast enhancement of given images, due to their simple function and effectiveness. However, the conventional histogram equalization (HE methods result in excessive contrast enhancement, which causes natural looking and satisfactory results for a variety of low contrast images. To solve such problems, a novel multi-histogram equalization technique is proposed to enhance the contrast of the palm bone X-ray radiographs in this paper. For images, the mean-variance analysis method is employed to partition the histogram of the original grey scale image into multiple sub-histograms. These histograms are independently equalized. By using this mean-variance partition method, a proposed multi-histogram equalization technique is employed to achieve the contrast enhancement of the palm bone X-ray radiographs. Experimental results show that the multi-histogram equalization technique achieves a lower average absolute mean brightness error (AMBE value. The multi-histogram equalization technique simultaneously preserved the mean brightness and enhanced the local contrast of the original image.

  1. Detection of cavernous transformation of the portal vein by contrast-enhanced ultrasound.

    Science.gov (United States)

    Hwang, Misun; Thimm, Matthew A; Guerrerio, Anthony L

    2018-06-01

    Cavernous transformation of the portal vein can be missed on color Doppler exam or arterial phase cross-sectional imaging due to their slow flow and delayed enhancement. Contrast-enhanced ultrasound (CEUS) offers many advantages over other imaging techniques and can be used to successfully detect cavernous transformations of the portal vein. A 10-month-old female was followed for repeat episodes of hematemesis. Computed tomography angiography (CTA) and magnetic resonance arteriogram (MRA) and portal venography were performed. Color Doppler exam of the portal vein was performed followed by administration of Lumason, a microbubble US contrast agent. Magnetic resonance arteriogram, CTA, and color Doppler exam at the time of initial presentation was unremarkable without obvious vascular malformation within the limits of motion degraded exam. At 8-month follow-up, esophagogastroduodenoscopy revealed a vascular malformation in the distal esophagus which was sclerosed. At 6 month after sclerosis of the lesion, portal venography revealed occlusion of the portal vein with extensive collateralization. Color Doppler revealed subtle hyperarterialization and periportal collaterals. CEUS following color Doppler exam demonstrated extensive enhancement of periportal collaterals. Repeat color Doppler after contrast administration demonstrated extensive Doppler signal in the collateral vessels, suggestive of cavernous transformation. We describe a case of cavernous transformation of the portal vein missed on initial color Doppler, CTA and MRA, but detected with contrast-enhanced ultrasound technique.

  2. Sequential contrast-enhanced MR imaging of the penis.

    Science.gov (United States)

    Kaneko, K; De Mouy, E H; Lee, B E

    1994-04-01

    To determine the enhancement patterns of the penis at magnetic resonance (MR) imaging. Sequential contrast material-enhanced MR images of the penis in a flaccid state were obtained in 16 volunteers (12 with normal penile function and four with erectile dysfunction). Subjects with normal erectile function showed gradual and centrifugal enhancement of the corpora cavernosa, while those with erectile dysfunction showed poor enhancement with abnormal progression. Sequential contrast-enhanced MR imaging provides additional morphologic information for the evaluation of erectile dysfunction.

  3. Image fusion for dynamic contrast enhanced magnetic resonance imaging

    Directory of Open Access Journals (Sweden)

    Leach Martin O

    2004-10-01

    Full Text Available Abstract Background Multivariate imaging techniques such as dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI have been shown to provide valuable information for medical diagnosis. Even though these techniques provide new information, integrating and evaluating the much wider range of information is a challenging task for the human observer. This task may be assisted with the use of image fusion algorithms. Methods In this paper, image fusion based on Kernel Principal Component Analysis (KPCA is proposed for the first time. It is demonstrated that a priori knowledge about the data domain can be easily incorporated into the parametrisation of the KPCA, leading to task-oriented visualisations of the multivariate data. The results of the fusion process are compared with those of the well-known and established standard linear Principal Component Analysis (PCA by means of temporal sequences of 3D MRI volumes from six patients who took part in a breast cancer screening study. Results The PCA and KPCA algorithms are able to integrate information from a sequence of MRI volumes into informative gray value or colour images. By incorporating a priori knowledge, the fusion process can be automated and optimised in order to visualise suspicious lesions with high contrast to normal tissue. Conclusion Our machine learning based image fusion approach maps the full signal space of a temporal DCE-MRI sequence to a single meaningful visualisation with good tissue/lesion contrast and thus supports the radiologist during manual image evaluation.

  4. Clinical utility of three-dimensional contrast-enhanced ultrasound in the differentiation between noninvasive and invasive neoplasms of urinary bladder.

    Science.gov (United States)

    Li, Qiu-yang; Tang, Jie; He, En-hui; Li, Yan-mi; Zhou, Yun; Zhang, Xu; Chen, Guangfu

    2012-11-01

    The purpose of this study was to evaluate the effectiveness of three-dimensional contrast-enhanced ultrasound in differentiating invasive and noninvasive neoplasms of urinary bladder. A total of 60 lesions in 60 consecutive patients with bladder tumors received three dimensional ultrasonography, low acoustic power contrast enhanced ultrasonography and low acoustic power three-dimensional contrast-enhanced ultrasound examination. The IU22 ultrasound scanner and a volume transducer were used and the ultrasound contrast agent was SonoVue. The contrast-specific sonographic imaging modes were PI (pulse inversion) and PM (power modulation). The three dimensional ultrasonography, contrast enhanced ultrasonography, and three-dimensional contrast-enhanced ultrasound images were independently reviewed by two readers who were not in the images acquisition. Images were analyzed off-site. A level of confidence in the diagnosis of tumor invasion of the muscle layer was assigned on a 5° scale. Receiver operating characteristic analysis was used to assess overall confidence in the diagnosis of muscle invasion by tumor. Kappa values were used to assess inter-readers agreement. Histologic diagnosis was obtained for all patients. Final pathologic staging revealed 44 noninvasive tumors and 16 invasive tumors. Three-dimensional contrast-enhanced ultrasound depicted all 16 muscle-invasive tumors. The diagnostic performance of three-dimensional contrast-enhanced ultrasound was better than those of three dimensional ultrasonography and contrast enhanced ultrasonography. The receiver operating characteristic curves were 0.976 and 0.967 for three-dimensional contrast-enhanced ultrasound, those for three dimensional ultrasonography were 0.881 and 0.869, those for contrast enhanced ultrasonography were 0.927 and 0.929. The kappa values in the three dimensional ultrasonography, contrast enhanced ultrasonography and three-dimensional contrast-enhanced ultrasound for inter-reader agreements

  5. Clinical utility of three-dimensional contrast-enhanced ultrasound in the differentiation between noninvasive and invasive neoplasms of urinary bladder

    International Nuclear Information System (INIS)

    Li, Qiu-yang; Tang, Jie; He, En-hui; Li, Yan-mi; Zhou, Yun; Zhang, Xu; Chen, Guangfu

    2012-01-01

    Objectives: The purpose of this study was to evaluate the effectiveness of three-dimensional contrast-enhanced ultrasound in differentiating invasive and noninvasive neoplasms of urinary bladder. Methods: A total of 60 lesions in 60 consecutive patients with bladder tumors received three dimensional ultrasonography, low acoustic power contrast enhanced ultrasonography and low acoustic power three-dimensional contrast-enhanced ultrasound examination. The IU22 ultrasound scanner and a volume transducer were used and the ultrasound contrast agent was SonoVue. The contrast-specific sonographic imaging modes were PI (pulse inversion) and PM (power modulation). The three dimensional ultrasonography, contrast enhanced ultrasonography, and three-dimensional contrast-enhanced ultrasound images were independently reviewed by two readers who were not in the images acquisition. Images were analyzed off-site. A level of confidence in the diagnosis of tumor invasion of the muscle layer was assigned on a 5° scale. Receiver operating characteristic analysis was used to assess overall confidence in the diagnosis of muscle invasion by tumor. Kappa values were used to assess inter-readers agreement. Histologic diagnosis was obtained for all patients. Results: Final pathologic staging revealed 44 noninvasive tumors and 16 invasive tumors. Three-dimensional contrast-enhanced ultrasound depicted all 16 muscle-invasive tumors. The diagnostic performance of three-dimensional contrast-enhanced ultrasound was better than those of three dimensional ultrasonography and contrast enhanced ultrasonography. The receiver operating characteristic curves were 0.976 and 0.967 for three-dimensional contrast-enhanced ultrasound, those for three dimensional ultrasonography were 0.881 and 0.869, those for contrast enhanced ultrasonography were 0.927 and 0.929. The kappa values in the three dimensional ultrasonography, contrast enhanced ultrasonography and three-dimensional contrast-enhanced ultrasound

  6. Contrast-enhanced versus systematic transrectal ultrasound-guided prostate cancer detection: An overview of techniques and a systematic review

    International Nuclear Information System (INIS)

    Heijmink, Stijn W.T.P.J.; Barentsz, Jelle O.

    2007-01-01

    An overview is given of the current conventional and contrast-specific transrectal ultrasound (TRUS) techniques for prostate imaging that may be used for guiding biopsy. Subsequently, a systematic literature search resulted in inclusion of four studies that directly compared systematic and contrast-enhanced-targeted TRUS-guided biopsy of the prostate. All four studies revealed that contrast-enhanced-targeted TRUS-guided biopsy significantly improved the positive biopsy core rate. In the largest study, the mean Gleason score of the contrast-enhanced-targeted TRUS-guided biopsies was significantly higher than that of the systematic biopsies. Future randomized clinical trials, preferably in a non-academic multi-institutional set-up, will have to be performed to confirm the value of contrast-enhanced-targeted TRUS-guided biopsy in regular clinical practice

  7. Contrast-enhanced ultrasound study of primary hepatic angiosarcoma: A pitfall of non-enhancement

    International Nuclear Information System (INIS)

    Wang, Liang; Lv, Ke; Chang, Xiao-Yan; Xia, Yu; Yang, Zhi-Ying; Jiang, Yu-Xin; Dai, Qing; Tan, Li; Li, Jian-Chu

    2012-01-01

    Highlights: ► The contrast-enhanced ultrasound (CEUS) characteristics of primary hepatic angiosarcoma (PHA) in three patients were retrospectively analyzed. ► PHA appeared similar peripheral enhancement pattern in our series. ► Non-necrotic tumor tissue of PHA unexpectedly demonstrated non-enhancement on CEUS. ► It may be associated with the very low velocity of blood flow in the central region of tumors. ► This interesting finding warrants further investigations, particularly on intratumoral hemodynamics. -- Abstract: Objective: To investigate the contrast-enhanced ultrasound (CEUS) characteristics of primary hepatic angiosarcoma (PHA). Methods: The sonographic findings and CEUS images of PHA in three patients were retrospectively analyzed. Results: In our study, 3 cases of PHA (2 multiple nodules and 1 solitary mass) showed similar enhancement pattern on CEUS, characterized by remarkable central non-enhancement and peripheral irregular enhancement in the arterial and portal phase, and complete wash-out in the late phase. Furthermore, we unexpectedly found that abundant neoplastic tissues were present in the central area of non-enhancement on pathological evaluation. Based on literature review, we supposed that the unusual finding may be associated with the very low velocity of blood flow in the central region of tumors. Conclusion: CEUS could well depict PHA with some common features, which may provide valuable clues in diagnosis of this rare disease. And non-necrotic tumor tissue of PHA could also demonstrate non-enhancement on CEUS, which warrant further investigations

  8. Usefulness of contrast-enhanced transabdominal ultrasound for tumor classification and tumor staging in the pancreatic head

    DEFF Research Database (Denmark)

    Grossjohann, Hanne Sønder; Rappeport, Eli David; Jensen, Claus Verner

    2010-01-01

    To evaluate contrast-enhanced ultrasound (CEUS) and compare it to ultrasound (US) and 64-slice-CT (64-CT) for diagnosing, staging and evaluation of resectability of pancreatic cancer.......To evaluate contrast-enhanced ultrasound (CEUS) and compare it to ultrasound (US) and 64-slice-CT (64-CT) for diagnosing, staging and evaluation of resectability of pancreatic cancer....

  9. Facial nerve palsy: Evaluation by contrast-enhanced MR imaging

    International Nuclear Information System (INIS)

    Kinoshita, T.; Ishii, K.; Okitsu, T.; Okudera, T.; Ogawa, T.

    2001-01-01

    AIM: The purpose of this study was to investigate the value of contrast-enhanced magnetic resonance (MR) imaging in patients with peripheral facial nerve palsy. MATERIALS AND METHODS: MR imaging was performed in 147 patients with facial nerve palsy, using a 1.0 T unit. All of 147 patients were evaluated by contrast-enhanced MR imaging and the pattern of enhancement was compared with that in 300 control subjects evaluated for suspected acoustic neurinoma. RESULTS: The intrameatal and labyrinthine segments of the normal facial nerve did not show enhancement, whereas enhancement of the distal intrameatal segment and the labyrinthine segment was respectively found in 67% and 43% of patients with Bell's palsy. The geniculate ganglion or the tympanic-mastoid segment was enhanced in 21% of normal controls versus 91% of patients with Bell's palsy. Abnormal enhancement of the non-paralyzed facial nerve was found in a patient with bilateral temporal bone fracture. CONCLUSION: Enhancement of the distal intrameatal and labyrinthine segments is specific for facial nerve palsy. Contrast-enhanced MR imaging can reveal inflammatory facial nerve lesions and traumatic nerve injury, including clinically silent damage in trauma. Kinoshita T. et al. (2001)

  10. Facial nerve palsy: Evaluation by contrast-enhanced MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kinoshita, T.; Ishii, K.; Okitsu, T.; Okudera, T.; Ogawa, T

    2001-11-01

    AIM: The purpose of this study was to investigate the value of contrast-enhanced magnetic resonance (MR) imaging in patients with peripheral facial nerve palsy. MATERIALS AND METHODS: MR imaging was performed in 147 patients with facial nerve palsy, using a 1.0 T unit. All of 147 patients were evaluated by contrast-enhanced MR imaging and the pattern of enhancement was compared with that in 300 control subjects evaluated for suspected acoustic neurinoma. RESULTS: The intrameatal and labyrinthine segments of the normal facial nerve did not show enhancement, whereas enhancement of the distal intrameatal segment and the labyrinthine segment was respectively found in 67% and 43% of patients with Bell's palsy. The geniculate ganglion or the tympanic-mastoid segment was enhanced in 21% of normal controls versus 91% of patients with Bell's palsy. Abnormal enhancement of the non-paralyzed facial nerve was found in a patient with bilateral temporal bone fracture. CONCLUSION: Enhancement of the distal intrameatal and labyrinthine segments is specific for facial nerve palsy. Contrast-enhanced MR imaging can reveal inflammatory facial nerve lesions and traumatic nerve injury, including clinically silent damage in trauma. Kinoshita T. et al. (2001)

  11. Contrast enhancement pattern in MR imaging of acute cerebral infarction

    International Nuclear Information System (INIS)

    Kim, Jong Deok; Cho, Mee Young; Lee, Chae Guk; Song, Dong Hoon

    1994-01-01

    To present the enhancement pattern of acute cerebral or cerebellar cortical infarctions aged 1-3 days on MR. Contrast-enhanced MR images of 26 patients with acute cerebral or cerebellar ischemic events were retrospectively reviewed. MR was performed within 3 days after ictus. Contrast enhancement in the area of infarction was observed in 61.5% (16/26) on MR. Of these 50% (13/26) showed non-parenchymal enhancement (NPE) representing either vascular or leptomeningeal enhancement, 7.7% (2/26) showed parenchymal enhancement (PE), and 2.8% (1/26) showed both NPE and PE. The earliest enhancement was seen in images obtained 12 hours after the onset of symptoms and appeared as NPE. One patient showed NPE without apparent high signal intensity at the corresponding area on T2-weighted images. In 38.5% (10/26), there was no enhancement. Contrast-enhanced MR imaging may be needed in acute ischemic infarction, because NPE may be seen as the earliest MR finding of acute cortical infraction aged 1-3 days

  12. Contrast enhancement pattern in MR imaging of acute cerebral infarction

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong Deok; Cho, Mee Young; Lee, Chae Guk; Song, Dong Hoon [Inje University College of Medicine, Pusan (Korea, Republic of)

    1994-08-15

    To present the enhancement pattern of acute cerebral or cerebellar cortical infarctions aged 1-3 days on MR. Contrast-enhanced MR images of 26 patients with acute cerebral or cerebellar ischemic events were retrospectively reviewed. MR was performed within 3 days after ictus. Contrast enhancement in the area of infarction was observed in 61.5% (16/26) on MR. Of these 50% (13/26) showed non-parenchymal enhancement (NPE) representing either vascular or leptomeningeal enhancement, 7.7% (2/26) showed parenchymal enhancement (PE), and 2.8% (1/26) showed both NPE and PE. The earliest enhancement was seen in images obtained 12 hours after the onset of symptoms and appeared as NPE. One patient showed NPE without apparent high signal intensity at the corresponding area on T2-weighted images. In 38.5% (10/26), there was no enhancement. Contrast-enhanced MR imaging may be needed in acute ischemic infarction, because NPE may be seen as the earliest MR finding of acute cortical infraction aged 1-3 days.

  13. Fundamentals of quantitative dynamic contrast-enhanced MR imaging.

    Science.gov (United States)

    Paldino, Michael J; Barboriak, Daniel P

    2009-05-01

    Quantitative analysis of dynamic contrast-enhanced MR imaging (DCE-MR imaging) has the power to provide information regarding physiologic characteristics of the microvasculature and is, therefore, of great potential value to the practice of oncology. In particular, these techniques could have a significant impact on the development of novel anticancer therapies as a promising biomarker of drug activity. Standardization of DCE-MR imaging acquisition and analysis to provide more reproducible measures of tumor vessel physiology is of crucial importance to realize this potential. The purpose of this article is to review the pathophysiologic basis and technical aspects of DCE-MR imaging techniques.

  14. The Feasibility of Contrast-Enhanced Ultrasound During Uterine Artery Embolization: A Pilot Study

    International Nuclear Information System (INIS)

    Dorenberg, Eric J.; Jakobsen, Jarl A.; Brabrand, Knut; Hafsahl, Geir; Smith, Hans-Jorgen

    2007-01-01

    Purpose. To evaluate the feasibility of using contrast-enhanced ultrasound (CEUS) during uterine artery embolization (UAE) in order to define the correct end-point of embolization with complete devascularization of all fibroids. Methods. In this prospective study of 10 consecutive women undergoing UAE, CEUS was performed in the angiographic suite during embolization. When the angiographic end-point, defined as the 'pruned-tree' appearance of the uterine arteries was reached, CEUS was performed while the angiographic catheters to both uterine arteries were kept in place. The decision whether or not to continue the embolization was based on the findings at CEUS. The results of CEUS were compared with those of contrast-enhanced magnetic resonance imaging (MRI) 1 day as well as 3 months following UAE. Results. CEUS was successfully performed in all women. In 4 cases injection of particles was continued based on the findings at CEUS despite angiographically complete embolization. CEUS imaging at completion of UAE correlated well with the findings at MRI. Conclusion. The use of CEUS during UAE is feasible and may increase the quality of UAE

  15. Radiofrequency ablation guided by contrast-enhanced ultrasound for hepatic malignancies: Preliminary results

    International Nuclear Information System (INIS)

    Dong, Y.; Wang, W.-P.; Gan, Y.-H.; Huang, B.-J.; Ding, H.

    2014-01-01

    Aim: To evaluate whether contrast-enhanced ultrasound (CEUS)-guided radiofrequency ablation (RFA) can be performed effectively in small hepatic malignancies that are invisible or poorly visualized at traditional grey-scale ultrasonography (US). Materials and methods: The institutional ethics committee approved the study, and all patients provided written informed consent before their enrolment. The study focused on 55 patients (43 men, 12 women, age 57.4 ± 10.9 years) with 60 hepatic lesions from May 2010 to March 2011. All lesions were treated with multipolar radiofrequency ablation (RFA). During the RFA procedure, with the injection of ultrasound contrast agent (sulphur hexafluoride; SonoVue, Bracco Imaging Spa, Milan, Italy), RFA was conducted under CEUS guidance when the optimal depiction of a lesion was obtained. Artificial pleural effusions were used in those cases obstructed by the lungs. Twenty-four hours after RFA, contrast-enhanced MRI was used as the reference standard to evaluate the primary effectiveness rate and complete tumour necrosis. The follow-up time was 12–24 months (median 15 months). Results: Among 60 hepatic malignancies, CEUS detected 57 lesions (95%), which was higher than that at US (26.6%). Artificial pleural effusions were performed in three cases, resulting in the detection of three additional lesions. The insertion of RFA electrodes was monitored by CEUS in all lesions. Immediately after RFA, complete tumour necrosis were achieved in all 60 lesions as apparent at MRI, for a primary effectiveness rate of 100%. Conclusion: CEUS-guided RFA is a promising technique for targeting and improving the efficiency of treatment of hepatic malignancies. - Highlights: • CEUS guided RFA improved the detectability of hepatic malignancies indistinctive on gray-scale ultrasound. • Pre-operation CEUS helped localization of indistinctive hepatic malignancies. • CEUS guided RFA of hepatic malignancies achieved a more complete ablation

  16. Contrast-enhanced ultrasound for diagnosis of prostate cancer and kidney lesions

    International Nuclear Information System (INIS)

    Mitterberger, Michael; Pelzer, Alexandre; Colleselli, Daniela; Bartsch, Georg; Strasser, Hannes; Pallwein, Leo; Aigner, Friedrich; Gradl, Johann; Frauscher, Ferdinand

    2007-01-01

    Purpose of review: Conventional ultrasonography of both, kidney and prostate, is limited due to the poor contrast of B-mode imaging for parenchymal disease and limited sensitivity of colour Doppler for the detection of capillaries and deep pedicular vessels. Contrast-enhanced ultrasound (CEUS) overcomes these limitations. Recent findings: CEUS investigates the blood flow of the prostate, allows for prostate cancer visualization and for targeted biopsies. Comparisons between systematic and CEUS-targeted biopsies have shown that the targeted approach detects more cancers with a lower number of biopsy cores and with higher Gleason scores compared with the systematic approach. Also the kidney offers promising applications as CEUS improves the detection of abnormal microvascular and macrovascular disorders. Summary: In recent literature CEUS has shown its value for diagnosis of both, prostate cancer and kidney lesions. This paper describes recent improvements and future perspectives of CEUS

  17. Fuzzy Logic-Based Histogram Equalization for Image Contrast Enhancement

    Directory of Open Access Journals (Sweden)

    V. Magudeeswaran

    2013-01-01

    Full Text Available Fuzzy logic-based histogram equalization (FHE is proposed for image contrast enhancement. The FHE consists of two stages. First, fuzzy histogram is computed based on fuzzy set theory to handle the inexactness of gray level values in a better way compared to classical crisp histograms. In the second stage, the fuzzy histogram is divided into two subhistograms based on the median value of the original image and then equalizes them independently to preserve image brightness. The qualitative and quantitative analyses of proposed FHE algorithm are evaluated using two well-known parameters like average information contents (AIC and natural image quality evaluator (NIQE index for various images. From the qualitative and quantitative measures, it is interesting to see that this proposed method provides optimum results by giving better contrast enhancement and preserving the local information of the original image. Experimental result shows that the proposed method can effectively and significantly eliminate washed-out appearance and adverse artifacts induced by several existing methods. The proposed method has been tested using several images and gives better visual quality as compared to the conventional methods.

  18. Contrast-enhanced color Doppler ultrasound characteristics in hypervascular breast tumors: comparison with MRI

    International Nuclear Information System (INIS)

    Alamo, L.; Fischer, U.

    2001-01-01

    The aim of this study was to evaluate the accuracy of contrast-enhanced color Doppler ultrasound (CE-US) in comparison with contrast-enhanced MR imaging (CE-MRI) in the discrimination of hypervascularized breast tumors. An additional CE-US of the breast was preoperatively performed in 40 patients with a hypervascular breast lesion detected on CE-MRI. The presence of blood flow signals and the morphological characteristics of the vessels in the breast lesions were evaluated pre- and post-contrast administration, as well as the dynamic aspects of the Doppler signal, including time interval to maximum signal enhancement and persistence of the signal enhancement. Twenty-three carcinomas and 17 fibroadenomas were explored. Considering initial signal enhancement > 100 % after the administration of contrast material as a criterion suggesting malignancy, CE-MRI showed a sensitivity of 100 % and a specificity of 76.5 % in the detection of malignant breast tumors. Color Doppler signals were consistently demonstrated in all carcinomas and in 68.7 % of fibroadenomas after the administration of Levovist, with CE-US showing a sensitivity of 95.6 % and a specificity of 5.9 %. Neither the mean number of vessels per tumor, nor the location of vessels, the time to maximum increase of the Doppler signal or the persistence of signal enhancement showed significant differences between benign and malignant lesions. Additional CE-US does not increase the low specificity of MRI in patients with hypervascularized breast tumors. (orig.)

  19. Evaluation of the thrombus of abdominal aortic aneurysms using contrast enhanced ultrasound - preliminary results

    Science.gov (United States)

    Łukasiewicz, Adam; Garkowski, Adam; Rutka, Katarzyna; Janica, Jacek; Łebkowska, Urszula

    2016-09-01

    It is hypothesized that the degree of vascularization of the thrombus may have a significant impact on the rupture of aortic aneurysms. The presence of neovascularization of the vessel wall and mural thrombus has been confirmed only in histopathological studies. However, no non-invasive imaging technique of qualitative assessment of thrombus and neovascularization has been implemented so far. Contrast-enhanced ultrasound (CEUS) has been proposed as a feasible and minimally invasive technique for in vivo visualization of neovascularization in the evaluation of tumors and atherosclerotic plaques. The aim of this study was the evaluation of mural thrombus and AAAs wall with CEUS. CEUS was performed in a group of seventeen patients with AAAs. The mural thrombus enhancement was recognized in 12 cases, yet no significant correlation between the degree of contrast enhancement and AAAs diameter, thrombus width, and thrombus echogenicity was found. We observed a rise in AAAs thrombus heterogeneity with the increase in the aneurysm diameter (r = 0.62, p = 0.017). In conclusion CEUS can visualize small channels within AAAs thrombus, which could be a result of an ongoing angiogenesis. There is a need for further research to find out whether the degree of vascularization of the thrombus may have a significant impact on the rupture of aneurysms.

  20. Contrast-enhanced ultrasound in diagnosis and characterization of focal hepatic lesions.

    Science.gov (United States)

    Molins, Inés Gómez; Font, Juan Manuel Fernández; Alvaro, Juan Carrero; Navarro, Jose Luís Lledó; Gil, Marta Fernández; Rodríguez, Conrado M Fernández

    2010-12-28

    The extensive use of imaging techniques in differential diagnosis of abdominal conditions and screening of hepatocellular carcinoma in patients with chronic hepatic diseases, has led to an important increase in identification of focal liver lesions. The development of contrast-enhanced ultrasound (CEUS) opens a new window in the diagnosis and follow-up of these lesions. This technique offers obvious advantages over the computed tomography and magnetic resonance, without a decrease in its sensitivity and specificity. The new second generation contrast agents, due to their intravascular distribution, allow a continuous evaluation of the enhancement pattern, which is crucial in characterization of liver lesions. The dual blood supply in the liver shows three different phases, namely arterial, portal and late phases. The enhancement during portal and late phases can give important information about the lesion's behavior. Each liver lesion has a different enhancement pattern that makes possible an accurate approach to their diagnosis. The role of emerging techniques as a contrast-enhanced three-dimensional US is also discussed. In this article, the advantages, indications and technique employed during CEUS and the different enhancement patterns of most benign and malignant focal liver lesions are discussed.

  1. Analysis of achilles tendon vascularity with second-generation contrast-enhanced ultrasound.

    Science.gov (United States)

    Genovese, Eugenio; Ronga, Mario; Recaldini, Chiara; Fontana, Federico; Callegari, Leonardo; Maffulli, Nicola; Fugazzola, Carlo

    2011-01-01

    To compare morphological, power Doppler, and contrast-enhanced ultrasound (CEUS) features of the Achilles tendon between asymptomatic athletes and athletes who had undergone surgical repair of a previous rupture. Twenty-four athletes were divided in two groups (A and B). Group A included 14 patients with a median age of 32 years (range 27 to 47 years) who had undergone surgical repair for unilateral Achilles tendon rupture. Group B (control group) included 10 subjects with a median age of 34 years (range 27 to 40 years) with no previous or present history of tendinopathy. All patients were evaluated with ultrasound, power Doppler, and CEUS with second-generation contrast agent. We studied the uninjured Achilles tendon in athletes of group A and either the left or the right Achilles tendon of the athletes in group B. CEUS showed a significantly greater ability to detect a greater number of vascular spots within the uninjured tendon of group A compared to group B (power Doppler ultrasound in the uninjured contralateral Achilles tendon. CEUS is useful to evaluate vascularity not detected by other imaging techniques. Vascularity in the uninjured tendon seems to be increased in patients who had a previous rupture. Copyright © 2011 Wiley Periodicals, Inc.

  2. Feasibility and usefulness of using swallow contrast-enhanced ultrasound to diagnose Zenker's diverticulum: preliminary results.

    Science.gov (United States)

    Cui, Xin-Wu; Ignee, Andre; Baum, Ulrich; Dietrich, Christoph F

    2015-04-01

    Zenker's diverticulum (ZD) may be misdiagnosed on conventional ultrasound as a thyroid nodule or other lesion. A barium esophagram is usually used to confirm the diagnosis; however, this procedure exposes the patient to radiation. The aim of this study was to evaluate the feasibility of using swallow contrast-enhanced ultrasound (swallow-CEUS) to diagnose ZD. Ten consecutive patients with ZD (7 men and 3 women, aged 67 ± 11 y) were included in the study. In 4 patients, ZD was incidentally found on head and neck ultrasound, and in 6 patients, ZD was suspected because of dysphagia. All lesions could be detected on conventional ultrasound before swallow-CEUS. Ten healthy volunteers (8 men and 2 women, aged 60 ± 12 y) were chosen as a control group. Written informed consent was obtained. With the patient in the sitting or upright position, conventional ultrasound was performed first to image the lesion, then the patient was asked to swallow ultrasound contrast agent (UCA) (2-4 drops of SonoVue diluted with about 200 mL of tap water). Transity of the contrast agent in the esophagus was imaged with CEUS. Retention of the UCA in the diverticulum was monitored for at least 3 min. All patients underwent a barium esophagram as the gold standard. Swallow-CEUS revealed that in all patients (100%), the UCA was transported from the pharynx to the esophagus while the patient swallowed. ZD appeared as a pouch-shaped structure at the posterior pharyngo-esophageal junction that retained UCA longer than 3 min. The barium esophagram confirmed the diagnosis of ZD in all patients. For the 10 volunteers, no abnormal structure (retaining UCA) was detected during or after swallowing of UCA. With the advantages of no radiation and bedside availability, swallow-CEUS may become a method of choice in confirmation of the diagnosis of ZD, especially when ZD is suspected on conventional ultrasound. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier

  3. Adaptive radiotherapy based on contrast enhanced cone beam CT imaging

    International Nuclear Information System (INIS)

    Soevik, Aaste; Skogmo, Hege K.; Roedal, Jan; Lervaag, Christoffer; Eilertsen, Karsten; Malinen, Eirik

    2010-01-01

    Cone beam CT (CBCT) imaging has become an integral part of radiation therapy, with images typically used for offline or online patient setup corrections based on bony anatomy co-registration. Ideally, the co-registration should be based on tumor localization. However, soft tissue contrast in CBCT images may be limited. In the present work, contrast enhanced CBCT (CECBCT) images were used for tumor visualization and treatment adaptation. Material and methods. A spontaneous canine maxillary tumor was subjected to repeated cone beam CT imaging during fractionated radiotherapy (10 fractions in total). At five of the treatment fractions, CECBCT images, employing an iodinated contrast agent, were acquired, as well as pre-contrast CBCT images. The tumor was clearly visible in post-contrast minus pre-contrast subtraction images, and these contrast images were used to delineate gross tumor volumes. IMRT dose plans were subsequently generated. Four different strategies were explored: 1) fully adapted planning based on each CECBCT image series, 2) planning based on images acquired at the first treatment fraction and patient repositioning following bony anatomy co-registration, 3) as for 2), but with patient repositioning based on co-registering contrast images, and 4) a strategy with no patient repositioning or treatment adaptation. The equivalent uniform dose (EUD) and tumor control probability (TCP) calculations to estimate treatment outcome for each strategy. Results. Similar translation vectors were found when bony anatomy and contrast enhancement co-registration were compared. Strategy 1 gave EUDs closest to the prescription dose and the highest TCP. Strategies 2 and 3 gave EUDs and TCPs close to that of strategy 1, with strategy 3 being slightly better than strategy 2. Even greater benefits from strategies 1 and 3 are expected with increasing tumor movement or deformation during treatment. The non-adaptive strategy 4 was clearly inferior to all three adaptive strategies

  4. Advanced ultrasound applications in the assessment of renal transplants: contrast-enhanced ultrasound, elastography, and B-flow.

    Science.gov (United States)

    Morgan, Tara A; Jha, Priyanka; Poder, Liina; Weinstein, Stefanie

    2018-04-09

    Ultrasound is routinely used as the first imaging exam for evaluation of renal transplants and can identify most major surgical complications and evaluate vascularity with color Doppler. Ultrasound is limited, however, in the detection of parenchymal disease processes and Doppler evaluation is also prone to technical errors. Multiple new ultrasound applications have been developed and are under ongoing investigation which could add additional diagnostic capability to the routine ultrasound exam with minimal additional time, cost, and patient risk. Contrast-enhanced ultrasound (CEUS) can be used off-label in the transplant kidney, and can assist in detection of infection, trauma, and vascular complications. CEUS also can demonstrate perfusion of the transplant assessed quantitatively with generation of time-intensity curves. Future directions of CEUS include monitoring treatment response and microbubble targeted medication delivery. Elastography is an ultrasound application that can detect changes in tissue elasticity, which is useful to diagnose diffuse parenchymal disease, such as fibrosis, otherwise unrecognizable with ultrasound. Elastography has been successfully applied in other organs including the liver, thyroid, and breast; however, it is still under development for use in the transplant kidney. Unique properties of the transplant kidney including its heterogeneity, anatomic location, and other technical factors present challenges in the development of reference standard measurements. Lastly, B-flow imaging is a flow application derived from B-mode. This application can show the true lumen size of a vessel which is useful to depict vascular anatomy and bypasses some of the pitfalls of color Doppler such as demonstration of slow flow.

  5. THE ABILITY OF CONTRAST-ENHANCED ULTRASOUND IN THE DIAGNOSIS OF LIVER METASTASES IN CERVICAL CANCER

    OpenAIRE

    V. S. Kryazheva; M. A. Chekalova; Z. R-B. Musaeva; V. V. Kuznetsov

    2017-01-01

    Objective: to explore the possibilities of contrast-enhanced ultrasound (CEUS) in the diagnosis of liver metastases in patients with a diagnosis of cervical cancer.Materials and methods. We analyzed the results of 4 clinical cases, of which 3 cases according CEUS diagnosed with liver metastases, in 1 case – nodular hyperplasia.Results and conclusions. Despite the small number of observations, we have concluded that the use of CEUS allows to expand possibilities of the ultrasound method in the...

  6. Image contrast enhancement based on a local standard deviation model

    International Nuclear Information System (INIS)

    Chang, Dah-Chung; Wu, Wen-Rong

    1996-01-01

    The adaptive contrast enhancement (ACE) algorithm is a widely used image enhancement method, which needs a contrast gain to adjust high frequency components of an image. In the literature, the gain is usually inversely proportional to the local standard deviation (LSD) or is a constant. But these cause two problems in practical applications, i.e., noise overenhancement and ringing artifact. In this paper a new gain is developed based on Hunt's Gaussian image model to prevent the two defects. The new gain is a nonlinear function of LSD and has the desired characteristic emphasizing the LSD regions in which details are concentrated. We have applied the new ACE algorithm to chest x-ray images and the simulations show the effectiveness of the proposed algorithm

  7. Contrast enhanced ultrasound in the evaluation and percutaneous treatment of hepatic and renal tumors

    International Nuclear Information System (INIS)

    Meloni, Maria Franca; Smolock, Amanda; Cantisani, Vito; Bezzi, Mario; D'Ambrosio, Ferdinando; Proiti, Maria; Lee, Fred; Aiani, Luca; Calliada, Fabrizio; Ferraioli, Giovanna

    2015-01-01

    Highlights: • Image-guided percutaneous ablation techniques are increasingly being used for the treatment of malignant tumors of the liver and kidney when surgery is not indicated. • Percutaneous ablation relies on imaging at every step of the process in order to detect, guide, and confirm complete tumor coagulation. • CEUS is a real-time dynamic imaging technique that plays an important role in the management of patients treated with ablation for malignant tumors. • This review focuses on the role of CEUS in the evaluation of patients undergoing percutaneous treatments for hepatic and renal tumors. - Abstract: Image-guided percutaneous ablation techniques are increasingly being used for the treatment of malignant tumors of the liver and kidney. Contrast enhanced ultrasound (CEUS) is a real-time dynamic imaging technique that plays an important role in the pre-, intra-, and post-procedural management of these patients. This review will focus on the role of CEUS in the evaluation of patients undergoing treatment with percutaneous ablation for hepatic or renal tumors

  8. Real-time contrast-enhanced ultrasound in diagnosing of focal spleen lesions

    International Nuclear Information System (INIS)

    Yu Xiaoling; Yu Jie; Liang Ping; Liu Fangyi

    2012-01-01

    Objective: To investigate the features of focal spleen lesions (FSLs) on contrast-enhanced ultrasound (CEUS) imaging. Materials and methods: CEUS with a blot injection of SonoVue was performed in 48 patients with 75 FSLs (median diameter 2.6 cm) and their perfusion characteristics were analyzed by using contrast pulse sequences (CPS) technique. Results: Among 19 malignant lesions (10 metastases, 7 lymphoma, 1 hemangiosarcoma, 1 epithelioid hemangioendothelioma) and 56 benign lesion (23 hemangiomas, 14 cysts, 8 infarctions, 4 splenic ruptures, 3 tuberculosis, 2 abscess, 1 pseudoaneurysm, 1 lymphangioma), 25 benign lesions were demonstrated nonenhancement. For malignancy, 50.0% (5/10) metastases and 57.1% (4/7) lymphomas were showed hypoenhancement in the arterial phase, and 18 (94.7%) of malignant lesions were hypo-enhancement in the parenchymal phase. Among 31 benign lesions with enhancement, 27 (87.1%) were showed isoenhancement or hyperenhancement in the arterial phase and 22 (71.0%) lesions were isoenhancement or hyperenhancement in the parenchymal phase. The sensitivity, specificity and accuracy of diagnosis for FSLs were 91.1%, 95.0% and 92.0% for CEUS and 75.0%, 84.2% and 77.3% respectively, for the conventional baseline ultrasound (BUS). Conclusion: Real-time CEUS can provide valuable information for the diagnosis and differential diagnosis of FSLs.

  9. Results of vardenafil mediated power Doppler ultrasound, contrast enhanced ultrasound and systematic random biopsies to detect prostate cancer.

    Science.gov (United States)

    Morelli, Girolamo; Pagni, Riccardo; Mariani, Chiara; Minervini, Riccardo; Morelli, Andrea; Gori, Francesco; Ferdeghini, Ezio Maria; Paterni, Marco; Mauro, Eva; Guidi, Elisa; Armillotta, Nicola; Canale, Domenico; Vitti, Paolo; Caramella, Davide; Minervini, Andrea

    2011-06-01

    We evaluated the ability of the phosphodiesterase-5 inhibitor vardenafil to increase prostate microcirculation during power Doppler ultrasound. We also evaluated the results of contrast and vardenafil enhanced targeted biopsies compared to those of standard 12-core random biopsies to detect cancer. Between May 2008 and January 2010, 150 consecutive patients with prostate specific antigen more than 4 ng/ml at first diagnosis with negative digital rectal examination and transrectal ultrasound, and no clinical history of prostatitis underwent contrast enhanced power Doppler ultrasound (bolus injection of 2.4 ml SonoVue® contrast agent), followed by vardenafil enhanced power Doppler ultrasound (1 hour after oral administration of vardenafil 20 mg). All patients underwent standard 12-core transrectal ultrasound guided random prostate biopsy plus 1 further sampling from each suspected hypervascular lesion detected by contrast and vardenafil enhanced power Doppler ultrasound. Prostate cancer was detected in 44 patients (29.3%). Contrast and vardenafil enhanced power Doppler ultrasound detected suspicious, contrast enhanced and vardenafil enhanced areas in 112 (74.6%) and 110 patients (73.3%), and was diagnostic for cancer in 32 (28.5%) and 42 (38%), respectively. Analysis of standard technique, and contrast and vardenafil enhanced power Doppler ultrasound findings by biopsy core showed significantly higher detection using vardenafil vs contrast enhanced power Doppler ultrasound and standard technique (41.2% vs 22.7% and 8.1%, p power Doppler ultrasound was 10% and 11.7% (p not significant). Vardenafil enhanced power Doppler ultrasound enables excellent visualization of the microvasculature associated with cancer and can improve the detection rate compared to contrast enhanced power Doppler ultrasound and the random technique. Copyright © 2011 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  10. Research on Wavelet-Based Algorithm for Image Contrast Enhancement

    Institute of Scientific and Technical Information of China (English)

    Wu Ying-qian; Du Pei-jun; Shi Peng-fei

    2004-01-01

    A novel wavelet-based algorithm for image enhancement is proposed in the paper. On the basis of multiscale analysis, the proposed algorithm solves efficiently the problem of noise over-enhancement, which commonly occurs in the traditional methods for contrast enhancement. The decomposed coefficients at same scales are processed by a nonlinear method, and the coefficients at different scales are enhanced in different degree. During the procedure, the method takes full advantage of the properties of Human visual system so as to achieve better performance. The simulations demonstrate that these characters of the proposed approach enable it to fully enhance the content in images, to efficiently alleviate the enhancement of noise and to achieve much better enhancement effect than the traditional approaches.

  11. Hepatic contrast-enhance ultrasound: impact of its introduction in the Australian context

    International Nuclear Information System (INIS)

    Won, So Yeun; Singh, Neha; Lim, Beng Ghee; Stella, Damien; Gibson, Robert

    2014-01-01

    Contrast-enhanced ultrasound (CEUS) is a relatively new imaging modality in Australia. We discuss our early experience with CEUS at Royal Melbourne Hospital in assessment of focal liver lesions and its clinical impact. Radiology department and hospital computerised information systems were used to identify and collate information regarding the indication, previous and follow-up imaging, CEUS findings and subsequent final diagnoses of patients who underwent hepatic CEUS from 12/12/2007 to 20/4/2012. A total of 388 hepatic CEUS were performed, examining 409 lesions. The cases were grouped as either 'initial study' or 'follow-up' group, with main focus on the former group. Of the 367 lesions in the 'initial study' group, CEUS was able to distinguish benign from malignant pathology in 344 cases (93.8%). This was especially beneficial in setting of known malignancy with indeterminate liver lesions found on CT to confidently exclude metastatic disease. For 124 of 162 patients who had an incidentally detected indeterminate liver lesion, CEUS was the final imaging investigation required to make a diagnosis. CEUS is a valuable tool in assessment of focal liver lesions in conjunction with other conventional modalities in a variety of clinical settings. In particular, it provided definitive diagnosis in a significant proportion of incidentally identified liver lesions many of which are benign, saving patient anxiety and further unnecessary follow-up.

  12. Changes of renal blood flow after ESWL: assessment by ASL MR imaging, contrast enhanced MR imaging, and renal resistive index.

    Science.gov (United States)

    Abd Ellah, Mohamed; Kremser, Christian; Pallwein, Leo; Aigner, Friedrich; Schocke, Michael; Peschel, Reinhard; Pedross, Florian; Pinggera, Germar-Michael; Wolf, Christian; Alsharkawy, Mostafa A M; Jaschke, Werner; Frauscher, Ferdinand

    2010-10-01

    The annual incidence of stone formation is increased in the industrialised world. Extracorporeal shockwave lithotripsy is a non-invasive effective treatment of upper urinary tract stones. This study is aimed to evaluate changes of renal blood flow in patients undergoing extracorporeal shock wave lithotripsy (ESWL) by arterial spin labeling (ASL) MR imaging, contrast enhanced dynamic MR imaging, and renal resistive index (RI). Thirteen patients with nephrolithiasis were examined using MR imaging and Doppler ultrasound 12h before and 12h after ESWL. ASL sequence was done for both kidneys and followed by contrast enhanced MR imaging. In addition RI Doppler ultrasound measurements were performed. A significant increase in RI (pESWL causes changes in RI and ASL MR imaging, which seem to reflect changes in renal blood flow. Copyright © 2009 Elsevier Ireland Ltd. All rights reserved.

  13. Magnetic iron oxide for contrast-enhanced MR imaging

    International Nuclear Information System (INIS)

    Fahlvik, A.K.

    1991-05-01

    The main objective of this experimental work has been to study the biological fate and the contrast enhancing potential of a model preparation of magnetic iron oxide (MSM) after intravenous injection to rodents. This was achieved by: Studying in vitro contrast efficacy of various magnetic iron oxide preparations by relaxation analysis. Studying in vivo contrast efficacy of MSM by relaxation analysis and NMR imaging. Studying the biodistribution and bioelimination of MSM in independent experiments using relaxation analysis, radioactivity studies and histological techniques. Studying interactions of MSM with target cells and target organelles using ex vivo techniques. Based on the presented experimental study, the MSM model preparation of magnetic iron oxide seems to fulfill basic requirements of NMR contrast agents: efficient proton relaxation, specific in vivo distribution, and biological tolerance. 177 refs., 5 figs., 2 tabs

  14. Contrast-enhanced ultrasound in the diagnosis of nodules in liver cirrhosis.

    Science.gov (United States)

    Kim, Tae Kyoung; Jang, Hyun-Jung

    2014-04-07

    Contrast-enhanced ultrasound (CEUS) using microbubble contrast agents are useful for the diagnosis of the nodules in liver cirrhosis. CEUS can be used as a problem-solving method for indeterminate nodules on computed tomography (CT) or magnetic resonance imaging (MRI) or as an initial diagnostic test for small newly detected liver nodules. CEUS has unique advantages over CT and MRI including no renal excretion of contrast, real-time imaging capability, and purely intravascular contrast. Hepatocellular carcinoma (HCC) is characterized by arterial-phase hypervascularity and later washout (negative enhancement). Benign nodules such as regenerative nodules or dysplastic nodules are usually isoechoic or slightly hypoechoic in the arterial phase and isoechoic in the late phase. However, there are occasional HCC lesions with atypical enhancement including hypovascular HCC and hypervascular HCC without washout. Cholangiocarcinomas are infrequently detected during HCC surveillance and mostly show rim-like or diffuse hypervascularity followed by rapid washout. Hemangiomas are often found at HCC surveillance and are easily diagnosed by CEUS. CEUS can be effectively used in the diagnostic work-up of small nodules detected at HCC surveillance. CEUS is also useful to differentiate malignant and benign venous thrombosis and to guide and monitor the local ablation therapy for HCC.

  15. Analysis of Achilles tendon vascularity with second generation Contrast-Enhanced Ultrasound (CEUS)

    OpenAIRE

    Genovese , Eugenio; Ronga , Mario; Recaldini , Chiara; Fontana , Federico; Callegari , Leonardo; Fugazzola , Carlo

    2011-01-01

    Abstract Purpose: To compare morphological and power Doppler features of the Achilles tendon and Contrast-Enhanced Ultrasound (CEUS) behaviour between asymptomatic athletes and athletes who had undergone surgery for repair of an Achilles tendon rupture. Materials and Methods: 24 athletes were divided in two groups (A and B). Group A included 14 patients with a median age of 32 years (range 27 to 47 years) who had undergone surgical repair for unilateral Achilles tendon ...

  16. THE ABILITY OF CONTRAST-ENHANCED ULTRASOUND IN THE DIAGNOSIS OF LIVER METASTASES IN CERVICAL CANCER

    Directory of Open Access Journals (Sweden)

    V. S. Kryazheva

    2017-01-01

    Full Text Available Objective: to explore the possibilities of contrast-enhanced ultrasound (CEUS in the diagnosis of liver metastases in patients with a diagnosis of cervical cancer.Materials and methods. We analyzed the results of 4 clinical cases, of which 3 cases according CEUS diagnosed with liver metastases, in 1 case – nodular hyperplasia.Results and conclusions. Despite the small number of observations, we have concluded that the use of CEUS allows to expand possibilities of the ultrasound method in the differential diagnosis of focal changes in the liver.

  17. Perfusion characteristics of parotid gland tumors evaluated by contrast-enhanced ultrasound

    Energy Technology Data Exchange (ETDEWEB)

    Klotz, Laura V., E-mail: Laura.Klotz@med.uni-muenchen.de [Department of Surgery, University of Munich, Munich (Germany); Gürkov, Robert [Department of Otorhinolaryngology, University of Munich, Munich (Germany); Eichhorn, Martin E. [Department of Surgery, University of Munich, Munich (Germany); Siedek, Vanessa; Krause, Eike [Department of Otorhinolaryngology, University of Munich, Munich (Germany); Jauch, Karl-Walter [Department of Surgery, University of Munich, Munich (Germany); Reiser, Maximilian F.; Clevert, Dirk-Andre [Department of Clinical Radiology, University of Munich, Munich (Germany)

    2013-12-01

    Purpose: Contrast enhanced ultrasound (CE-US) is a promising imaging modality for non-invasive analysis of parotid gland lesions because their vascularisation differs from normal gland tissue. This clinical study should further investigate CE-US as a diagnostic tool for parotid gland tumors. Materials and methods: 39 patients underwent CE-US measurements after intravenous application of a contrast agent (SonoVue, Bracco, Italy) before surgical tumor resection. Time–intensity curves gradients were calculated and parameters of intratumoral microcirculation were analysed. The vascularisation parameters were compared among the different tumor entities as defined per definitive histological diagnosis. Results: Histological analyses revealed 17 pleomorphic adenoma, 15 cystadenolymphoma and 7 malignoma. A significant difference of area below intensity time curve (AUC) and mean transit time (MTT) was measured in the malignant lesions compared to benign tumors (p < 0.05). A significant difference of AUC and maximum of signal increase (ΔSI{sub max}) for pleomorphic adenoma versus cystadenolymphoma was found (p < 0.05). Conclusion: CE-US seems to be a quantitative and independent method for the assessment of malign and benign parotid gland tumors. Further studies and clinical experience will have to validate this method as a reliable diagnostic tool that facilitates preoperative planning.

  18. Polycystic ovary syndrome: dynamic contrast-enhanced ovary MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Erdem, C. Zuhal E-mail: sunarerdem@yahoo.com; Bayar, Ulku; Erdem, L. Oktay; Barut, Aykut; Gundogdu, Sadi; Kaya, Erdal

    2004-07-01

    Objective: to determine the enhancement behaviour of the ovaries in women with polycystic ovary syndrome (PCOS) by dynamic contrast-enhanced magnetic resonance (DCE-MR) imaging and to compare these data with those of normal ovulating controls. Method: 24 women with PCOS and 12 controls underwent DCE-MR imaging. Dynamic images were acquired before and after injection of a contrast bolus at 30 s and the min of 1, 2, 3, 4 and 5. On postprocessing examination: (i) the ovarian volumes; (ii) the signal intensity value of each ovary per dynamic study; (iii) early-phase enhancement rate; (iv) time to peak enhancement (T{sub p}); and (v) percentage of washout of 5th min were determined. Data of the ovaries of the women with PCOS and controls were compared with Mann-Whitney U-test. Results: the mean values of T{sub p} were found to be significantly lower in women with PCOS than in controls (p<0.05). On the other hand, the mean values of ovarian volume, the early-phase enhancement rate, and percentage of washout of 5th min of ovaries were significantly higher in PCOS patients (p<0.05). Examination of the mean signal intensity-time curve revealed the ovaries in women with PCOS showed a faster and greater enhancement and wash-out. Conclusion: the enhancement behaviour of ovaries of women with PCOS may be significantly different from those of control subjects on DCE-MR imaging examination. In our experience, it is a valuable modality to highlight the vascularization changes in ovarian stroma with PCOS. We believe that improved DCE-MR imaging techniques may also provide us additional parameters in the diagnosis and treatment strategies of PCOS.

  19. Polycystic ovary syndrome: dynamic contrast-enhanced ovary MR imaging

    International Nuclear Information System (INIS)

    Erdem, C. Zuhal; Bayar, Ulku; Erdem, L. Oktay; Barut, Aykut; Gundogdu, Sadi; Kaya, Erdal

    2004-01-01

    Objective: to determine the enhancement behaviour of the ovaries in women with polycystic ovary syndrome (PCOS) by dynamic contrast-enhanced magnetic resonance (DCE-MR) imaging and to compare these data with those of normal ovulating controls. Method: 24 women with PCOS and 12 controls underwent DCE-MR imaging. Dynamic images were acquired before and after injection of a contrast bolus at 30 s and the min of 1, 2, 3, 4 and 5. On postprocessing examination: (i) the ovarian volumes; (ii) the signal intensity value of each ovary per dynamic study; (iii) early-phase enhancement rate; (iv) time to peak enhancement (T p ); and (v) percentage of washout of 5th min were determined. Data of the ovaries of the women with PCOS and controls were compared with Mann-Whitney U-test. Results: the mean values of T p were found to be significantly lower in women with PCOS than in controls (p<0.05). On the other hand, the mean values of ovarian volume, the early-phase enhancement rate, and percentage of washout of 5th min of ovaries were significantly higher in PCOS patients (p<0.05). Examination of the mean signal intensity-time curve revealed the ovaries in women with PCOS showed a faster and greater enhancement and wash-out. Conclusion: the enhancement behaviour of ovaries of women with PCOS may be significantly different from those of control subjects on DCE-MR imaging examination. In our experience, it is a valuable modality to highlight the vascularization changes in ovarian stroma with PCOS. We believe that improved DCE-MR imaging techniques may also provide us additional parameters in the diagnosis and treatment strategies of PCOS

  20. Contrast-enhanced fast fluid-attenuated inversion recovery MR imaging in patients with brain tumors

    International Nuclear Information System (INIS)

    Kim, Chan Kyo; Na, Dong Gyu; Ryoo, Wook Jae; Byun Hong Sik; Yoon, Hye Kyung; Kim, Jong hyun

    2000-01-01

    To assess the feasibility of contrast-enhanced fast fluid-attenuated inversion recovery (fast FLAIR) MR imaging in patients with brain tumors. This study involved 31 patients with pathologically proven brain tumors and nine with clinically diagnosed metastases. In all patients, T2-weighted, fast FLAIR, images were visual contrast-enhanced T1-weighted MR images were obtained. Contrast-enhanced fast FLAIR images were visually compared with other MR sequences in terms of tumor conspicuity. In order to distinguish tumor and surrounding edema, contrast-enhanced fast FLAIR images were compared with fast FLAIR and T2-weighted images. The tumor-to- white matter contrast-to-noise ratios (CNRs), as demonstrated by T2-weighted, fast FLAIR, contrast-enhanced fast FLAIR and contrast-enhanced T1-weighted imaging, were quantitatively assessed and compared. For the visual assessment of tumor conspicuity, contrast-enhanced fast FLAIR image imaging superior to fast FLAIR in 60% of cases (24/40), and superior to T2-weighted in 70% (28/40). Contrast-enhanced fast FLAIR imaging was inferior to contrast-enhanced T1-weighted in 58% of cases (23/40). For distinguishing between tumor and surrounding edema, contrast-enhanced fast FLAIR imaging was superior to fast FLAIR or T2-weighted in 22 of 27 tumors with peritumoral edema (81%). Quantitatively, CNR was the highest on contrast-enhanced fast FLAIR image and the lowest on fast FLAIR. For the detection of leptomeningeal metastases, contrast-enhanced fast FLAIR was partially superior to contrast-enhanced T1-weighted imaging in two of three high-grade gliomas. Although contrast-enhanced fast FLAIR imaging should not be seen as a replacement for conventional modalities, it provides additional informaton for assessment of the extent of glial cell tumors and leptomeningeal metastases in patients with brain tumors. (author)

  1. Breast tumor size assessment: comparison of conventional ultrasound and contrast-enhanced ultrasound.

    Science.gov (United States)

    Jiang, Yu-Xin; Liu, He; Liu, Ji-Bin; Zhu, Qing-Li; Sun, Qiang; Chang, Xiao-Yan

    2007-12-01

    Accurate assessment of tumor size is necessary when selecting patients for breast-conserving surgery. In the study of breast contrast-enhanced ultrasound (CEUS), we found that tumor size discrepancy between CEUS and conventional ultrasound (US) existed in some breast lesions, for which the reasons are not clear. Breast CEUS examinations were performed in 104 patients with breast lesions. The measurement of the 104 breast tumors on conventional US was obtained and compared with the measurement on CEUS. A difference in measuring tumor size of >3 mm for tumors up to 1.7 cm and 4 mm for tumors >or=1.7 cm, was defined as a significant discrepancy between conventional US and CEUS. The histopathological examination of size discrepancy was performed and the margin characteristics of breast cancers with larger measurements were compared with those with unchanged measurements. Among the 104 lesions (43 malignant, 60 benign, 1 borderline), the size of 27 breast cancers and one granulomatous mastitis appeared larger at CEUS. Pathologic examinations of the region corresponding to the measurement discrepancy were mainly ductal carcinomas in situ (DCIS), invasive carcinoma with a DCIS component, adenosis with lobular hyperplasia in breast cancers and inflammatory cell infiltration in one granulomatous mastitis. Well-defined margin characteristics were significantly different between breast cancers with larger measurements at CEUS and those with unchanged measurements of size (p = 0.002), whereas no significant difference was found between the two groups in ill-defined, spiculated, hyperechoic halo, microlobulated and angulated margins (p = 0.463, 0.117, 0.194, 0.666 and 0.780, respectively). This initial study suggests that significant discrepancy of breast lesion measurement between conventional US and CEUS is more likely presented in breast cancer than benign lesions. The pathologic findings corresponding to the region of size increased at CEUS are malignant in most malignant

  2. Local gray level S-curve transformation - A generalized contrast enhancement technique for medical images.

    Science.gov (United States)

    Gandhamal, Akash; Talbar, Sanjay; Gajre, Suhas; Hani, Ahmad Fadzil M; Kumar, Dileep

    2017-04-01

    Most medical images suffer from inadequate contrast and brightness, which leads to blurred or weak edges (low contrast) between adjacent tissues resulting in poor segmentation and errors in classification of tissues. Thus, contrast enhancement to improve visual information is extremely important in the development of computational approaches for obtaining quantitative measurements from medical images. In this research, a contrast enhancement algorithm that applies gray-level S-curve transformation technique locally in medical images obtained from various modalities is investigated. The S-curve transformation is an extended gray level transformation technique that results into a curve similar to a sigmoid function through a pixel to pixel transformation. This curve essentially increases the difference between minimum and maximum gray values and the image gradient, locally thereby, strengthening edges between adjacent tissues. The performance of the proposed technique is determined by measuring several parameters namely, edge content (improvement in image gradient), enhancement measure (degree of contrast enhancement), absolute mean brightness error (luminance distortion caused by the enhancement), and feature similarity index measure (preservation of the original image features). Based on medical image datasets comprising 1937 images from various modalities such as ultrasound, mammograms, fluorescent images, fundus, X-ray radiographs and MR images, it is found that the local gray-level S-curve transformation outperforms existing techniques in terms of improved contrast and brightness, resulting in clear and strong edges between adjacent tissues. The proposed technique can be used as a preprocessing tool for effective segmentation and classification of tissue structures in medical images. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Application of contrast-enhanced ultrasound in the diagnosis of solid pancreatic lesions—A comparison of conventional ultrasound and contrast-enhanced CT

    International Nuclear Information System (INIS)

    Fan, Zhihui; Li, Ying; Yan, Kun; Wu, Wei; Yin, Shanshan; Yang, Wei; Xing, Baocai

    2013-01-01

    Objective: To explore the diagnostic value of contrast-enhanced ultrasound (CEUS) by comparison with conventional ultrasound (US) and contrast-enhanced CT (CECT) in solid pancreatic lesions. Method: Ninety patients with solid pancreatic focal lesions were enrolled, including 36 cases of pancreatic carcinoma, 28 cases of pancreatitis, 6 cases of pancreatic neuroendocrine tumor, 12 cases of solid pseudopapillary tumor of the pancreas, 6 cases of pancreatic metastases, 1 case of cavernous hemolymphangioma and 1 case of lymphoma. US and CEUS were applied respectively for the diagnosis of a total of 90 cases of solid pancreatic lesions. The diagnostic results were scored on a 5-point scale. Results of CEUS were compared with CECT. Results: (1) 3-score cases (undetermined) diagnosed by CEUS were obviously fewer than that of US, while the number of 1-score (definitely benign) and 5-score (definitely malignant) cases diagnosed by CEUS was significantly more than that of US. There was a significant difference in the distribution of final scores using the two methods (p < 0.001). The overall diagnostic accuracies of the 90 cases for CEUS and US were 83.33% and 44.44%, respectively, which indicated an obvious advantage for CEUS (p < 0.001). (2) The diagnostic consistency among three ultrasound doctors: the kappa values calculated for US were 0.537, 0.444 and 0.525, compared with 0.748, 0.645 and 0.795 for CEUS. The interobserver agreement for CEUS was higher than that for US. (3) The sensitivity, specificity and accuracy of the diagnosis of pancreatic carcinoma with CEUS and CECT were 91.7% and 97.2%, 87.0% and 88.9%, and 88.9% and 92.2%, respectively, while for the diagnosis of pancreatitis, the corresponding indices were 82.1% and 67.9%, 91.9% and 100%, and 88.9% and 90%, respectively, showing no significant differences (p > 0.05). Conclusion: CEUS has obvious superiority over conventional US in the general diagnostic accuracy of solid pancreatic lesions and in the

  4. Application of contrast-enhanced ultrasound in the diagnosis of solid pancreatic lesions—A comparison of conventional ultrasound and contrast-enhanced CT

    Energy Technology Data Exchange (ETDEWEB)

    Fan, Zhihui, E-mail: fanzhihui_1026@163.com [Key Laboratory of Carcinogenesis and Translational Research, Ministry of Education, Department of Ultrasound, Peking University Cancer Hospital and Institute, No. 52, Fucheng Road, Haidian District, Beijing 100142 (China); Li, Ying, E-mail: 18901033676@126.com [Key Laboratory of Carcinogenesis and Translational Research, Ministry of Education, Department of Radiology, Peking University Cancer Hospital and Institute, No. 52, Fucheng Road, Haidian District, Beijing 100142 (China); Yan, Kun, E-mail: ydbz@sina.com [Key Laboratory of Carcinogenesis and Translational Research, Ministry of Education, Department of Ultrasound, Peking University Cancer Hospital and Institute, No. 52, Fucheng Road, Haidian District, Beijing 100142 (China); Wu, Wei, E-mail: wuwei@163.com [Key Laboratory of Carcinogenesis and Translational Research, Ministry of Education, Department of Ultrasound, Peking University Cancer Hospital and Institute, No. 52, Fucheng Road, Haidian District, Beijing 100142 (China); Yin, Shanshan, E-mail: yshshmd@yahoo.com [Key Laboratory of Carcinogenesis and Translational Research, Ministry of Education, Department of Ultrasound, Peking University Cancer Hospital and Institute, No. 52, Fucheng Road, Haidian District, Beijing 100142 (China); Yang, Wei, E-mail: weiwei02032001@gmail.com [Key Laboratory of Carcinogenesis and Translational Research, Ministry of Education, Department of Ultrasound, Peking University Cancer Hospital and Institute, No. 52, Fucheng Road, Haidian District, Beijing 100142 (China); Xing, Baocai, E-mail: xinbaocai88@sina.com [Key Laboratory of Carcinogenesis and Translational Research, Ministry of Education, Department of Hepatic Biliary and Pancreatic Surgery, Peking University Cancer Hospital and Institute, No. 52, Fucheng Road, Haidian District, Beijing 100142 (China); and others

    2013-09-15

    Objective: To explore the diagnostic value of contrast-enhanced ultrasound (CEUS) by comparison with conventional ultrasound (US) and contrast-enhanced CT (CECT) in solid pancreatic lesions. Method: Ninety patients with solid pancreatic focal lesions were enrolled, including 36 cases of pancreatic carcinoma, 28 cases of pancreatitis, 6 cases of pancreatic neuroendocrine tumor, 12 cases of solid pseudopapillary tumor of the pancreas, 6 cases of pancreatic metastases, 1 case of cavernous hemolymphangioma and 1 case of lymphoma. US and CEUS were applied respectively for the diagnosis of a total of 90 cases of solid pancreatic lesions. The diagnostic results were scored on a 5-point scale. Results of CEUS were compared with CECT. Results: (1) 3-score cases (undetermined) diagnosed by CEUS were obviously fewer than that of US, while the number of 1-score (definitely benign) and 5-score (definitely malignant) cases diagnosed by CEUS was significantly more than that of US. There was a significant difference in the distribution of final scores using the two methods (p < 0.001). The overall diagnostic accuracies of the 90 cases for CEUS and US were 83.33% and 44.44%, respectively, which indicated an obvious advantage for CEUS (p < 0.001). (2) The diagnostic consistency among three ultrasound doctors: the kappa values calculated for US were 0.537, 0.444 and 0.525, compared with 0.748, 0.645 and 0.795 for CEUS. The interobserver agreement for CEUS was higher than that for US. (3) The sensitivity, specificity and accuracy of the diagnosis of pancreatic carcinoma with CEUS and CECT were 91.7% and 97.2%, 87.0% and 88.9%, and 88.9% and 92.2%, respectively, while for the diagnosis of pancreatitis, the corresponding indices were 82.1% and 67.9%, 91.9% and 100%, and 88.9% and 90%, respectively, showing no significant differences (p > 0.05). Conclusion: CEUS has obvious superiority over conventional US in the general diagnostic accuracy of solid pancreatic lesions and in the

  5. Patterns of appearance and risk of misdiagnosis of intrahepatic cholangiocarcinoma in cirrhosis at contrast enhanced ultrasound.

    Science.gov (United States)

    Galassi, Marzia; Iavarone, Massimo; Rossi, Sandro; Bota, Simona; Vavassori, Sara; Rosa, Laura; Leoni, Simona; Venerandi, Laura; Marinelli, Sara; Sangiovanni, Angelo; Veronese, Letizia; Fraquelli, Mirella; Granito, Alessandro; Golfieri, Rita; Colombo, Massimo; Bolondi, Luigi; Piscaglia, Fabio

    2013-05-01

    Primary aim was to validate the percentage of intrahepatic cholangiocarcinomas (ICC) which have a contrast vascular pattern at contrast enhanced ultrasound (CEUS) at risk of misdiagnosis with hepatocellular carcinoma (HCC) and, secondary aim, to verify if any characteristics in the CEUS pattern helps to identify ICC. All ICC on cirrhosis seen in three Italian centres (Bologna, Milan and Pavia) between 2003 and 2011, in which CEUS and at least another imaging technique (CT or MRI) had been performed, were retrospectively identified. Those patients with ICC size comparable to the early HCC stage (Milan criteria, considered as small ICC) were enrolled for this study. The enhancement pattern at CEUS was analysed and compared with CT or MRI. A total of 25 small ICC made this study group. CEUS was at risk of misdiagnosis of ICC for HCC in a significantly higher number of cases than in CT (performed in 24 ICC) (52% vs. 4.2%, P = 0.009) and MRI (11 ICC) (52% vs. 9.1%, P = 0.02). A different contrast pattern among all techniques was found in 6 of 10 ICC lesions submitted to the three imaging methods. In the arterial phase, ICC lacked global hyperenhacement in approximately 50% of cases at CEUS and the degree of intensity of wash-out in the late phase was marked in 24% of nodules. CEUS misdiagnosed as HCC a significantly higher number of ICC lesions in cirrhotic patients than CT and MRI. However, some CEUS contrast features can help suspect ICC, especially in some cases with inconclusive CT or MRI. © 2013 John Wiley & Sons A/S.

  6. Contrast-enhanced Ultrasound for Detection of Crohn's Disease Activity: Systematic Review and Meta-analysis.

    Science.gov (United States)

    Serafin, Zbigniew; Białecki, Marcin; Białecka, Agnieszka; Sconfienza, Luca Maria; Kłopocka, Maria

    2016-03-01

    Reports on imaging of active Crohn's disease (aCD) using contrast-enhanced ultrasound (CEUS) are encouraging. However, the statistical power of most published papers is limited due to the small size of the patient groups included. This study was performed to verify the diagnostic value of CEUS in detecting aCD. A systematic literature search was performed by two independent reviewers for articles on the test characteristics of CEUS for the identification of aCD. The quality of the analysed studies was evaluated using a quality assessment tool for diagnostic accuracy studies (QUADAS-2). Pooling was performed using a diagnostic random-effect model and bivariate analysis. Eight articles were included in the final analysis, with a total of 332 patients. There was no significant publication bias. Significant heterogeneity was found regarding CEUS methodology and sonographic definitions of aCD. In a bivariate analysis, pooled sensitivity was 0.94 (95% CI 0.87-0.97) and pooled specificity was 0.79 (95% CI 0.67-0.88). Spearman correlation statistics presented no significant diagnostic threshold effect (r = 0.12, p > 0.9). Subgroup analysis showed that relative intestine wall enhancement had the highest diagnostic value (area under the curve 94%), while the presence of enhancement and analysis of the slope were less useful (area under the curve 91 and 90%, respectively). CEUS presents good sensitivity and moderate specificity in the detection of the aCD. Large-scale randomized trials with quantitative evaluation of CEUS images are necessary to promote this technique in clinical practice. Copyright © 2015 European Crohn’s and Colitis Organisation (ECCO). Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  7. Changes of renal blood flow after ESWL: Assessment by ASL MR imaging, contrast enhanced MR imaging, and renal resistive index

    Energy Technology Data Exchange (ETDEWEB)

    Abd Ellah, Mohamed, E-mail: dr_m_hamdy2006@hotmail.co [Innsbruck Medical University, Radiology Dept., Anich St. 35, 6020 Innsbruck (Austria); Kremser, Christian, E-mail: christian.kremser@i-med.ac.a [Innsbruck Medical University, Radiology Dept., Anich St. 35, 6020 Innsbruck (Austria); Pallwein, Leo, E-mail: leo.pallwein-prettner@uki.a [Innsbruck Medical University, Radiology Dept., Anich St. 35, 6020 Innsbruck (Austria); Aigner, Friedrich, E-mail: friedrich.Aigner@uki.a [Innsbruck Medical University, Radiology Dept., Anich St. 35, 6020 Innsbruck (Austria); Schocke, Michael, E-mail: michael.schocke@i-med.ac.a [Innsbruck Medical University, Radiology Dept., Anich St. 35, 6020 Innsbruck (Austria); Peschel, Reinhard, E-mail: reinhard.peschel@uki.a [Innsbruck Medical University, Urology Dept., Anich St. 35, 6020 Innsbruck (Austria); Pedross, Florian, E-mail: florian.pedross@i-med.ac.a [Innsbruck Medical University, Medical Statistics Dept., Anich St. 35, 6020 Innsbruck (Austria); Pinggera, Germar-Michael, E-mail: germar.pinggera@uki.a [Innsbruck Medical University, Urology Dept., Anich St. 35, 6020 Innsbruck (Austria); Wolf, Christian, E-mail: christian.wolf@bkh-reutte.a [Innsbruck Medical University, Radiology Dept., Anich St. 35, 6020 Innsbruck (Austria); Alsharkawy, Mostafa A.M., E-mail: drmostafamri@yahoo.co [Assiut University, Radiology Dept., Assiut (Egypt); Jaschke, Werner, E-mail: werner.jaschke@i-med.ac.a [Innsbruck Medical University, Radiology Dept., Anich St. 35, 6020 Innsbruck (Austria); Frauscher, Ferdinand, E-mail: ferdinand.frauscher@uki.a [Innsbruck Medical University, Radiology Dept., Anich St. 35, 6020 Innsbruck (Austria)

    2010-10-15

    The annual incidence of stone formation is increased in the industrialised world. Extracorporeal shockwave lithotripsy is a non-invasive effective treatment of upper urinary tract stones. This study is aimed to evaluate changes of renal blood flow in patients undergoing extracorporeal shock wave lithotripsy (ESWL) by arterial spin labeling (ASL) MR imaging, contrast enhanced dynamic MR imaging, and renal resistive index (RI). Thirteen patients with nephrolithiasis were examined using MR imaging and Doppler ultrasound 12 h before and 12 h after ESWL. ASL sequence was done for both kidneys and followed by contrast enhanced MR imaging. In addition RI Doppler ultrasound measurements were performed. A significant increase in RI (p < 0.001) was found in both treated and untreated kidneys. ASL MR imaging also showed significant changes in both kidneys (p < 0.001). Contrast enhanced dynamic MR imaging did not show significant changes in the kidneys. ESWL causes changes in RI and ASL MR imaging, which seem to reflect changes in renal blood flow.

  8. Assessment of arterial hypervascularity of hepatocellular carcinoma: comparison of contrast-enhanced US and gadoxetate disodium-enhanced MR imaging

    International Nuclear Information System (INIS)

    Sugimoto, Katsutoshi; Moriyasu, Fuminori; Taira, Junichi; Imai, Yasuharu; Shiraishi, Junji; Saito, Kazuhiro; Saguchi, Toru

    2012-01-01

    To compare contrast-enhanced (CE) ultrasound with gadoxetate disodium-enhanced magnetic resonance (MR) imaging in the assessment of arterial hypervascularity of hepatocellular carcinoma (HCC) and dysplastic nodule (DN), with CT during hepatic arteriography (CTHA) as the reference standard. This study included 54 consecutively diagnosed patients, with 57 histologically confirmed HCCs and 3 DNs (high-grade). All patients underwent CE ultrasound, gadoxetate disodium-enhanced MR imaging and CTHA. Two trained diagnostic radiologists interpreted the CTHA images and rated the degree of intratumoral arterial vascularity by consensus using a five-point confidence scale as the reference standard. In the observer study, the degrees of vascularity on CE ultrasound and gadoxetate disodium-enhanced MR images were qualitatively analysed by four independent readers using a five-point confidence scale. Diagnostic accuracy was analysed by receiver-operating characteristic (ROC) analysis. The diagnostic accuracies of the average area under the ROC curve (AUC) were significantly greater with CE ultrasound (average AUC: 0.94; 95% confidence interval [CI]: 0.88-1.00) than with gadoxetate disodium-enhanced MR imaging (average AUC 0.84, 95% CI 0.74-0.93, P = 0.0014). Contrast-enhanced ultrasound yields a significantly higher AUC value than gadoxetate disodium-enhanced MR imaging in the assessment of arterial hypervascularity of HCC and DN. Key Points circle Arterial hypervascularity is an important feature determining treatment options in hepatocellular carcinoma. circle It can be assessed by contrast-enhanced (CE) ultrasound or magnetic resonance (MR) imaging. circle CE ultrasound was more accurate than Gd-EOB-DTPA MRI in assessing intratumoral vascularity. circle Hypovascular hepatic nodules should be further investigated using CE ultrasound. (orig.)

  9. Small nodules (1-2 cm) in liver cirrhosis: Characterization with contrast-enhanced ultrasound

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Hyun-Jung [Department of Medical Imaging, Toronto General Hospital, University of Toronto, 585 University Avenue, Toronto, Ontario M5G 2N2 (Canada); Kim, Tae Kyoung [Department of Medical Imaging, Toronto General Hospital, University of Toronto, 585 University Avenue, Toronto, Ontario M5G 2N2 (Canada)], E-mail: taekyoung.kim@uhn.on.ca; Wilson, Stephanie R. [Department of Medical Imaging, Toronto General Hospital, University of Toronto, 585 University Avenue, Toronto, Ontario M5G 2N2 (Canada)

    2009-12-15

    Objective: To determine the diagnostic efficacy of arterial phase contrast-enhanced ultrasound (CEUS) for characterizing small hepatic nodules (1-2 cm) in patients with high-risk for hepatocellular carcinoma (HCC). Materials and methods: Over 12 months, CEUS was performed in 59 patients at high-risk for HCC with small hepatic nodules (1-2 cm; mean, 1.5 cm). Based only on arterial phase (<45 s) vascular intensity and pattern, lesions were prospectively diagnosed as HCC if there was hypervascularity without known features of hemangioma. The diagnosis of HCC was made regardless of the presence or absence of washout. Verification of diagnosis was made by liver transplantation (n = 13), biopsy (n = 12), resection (n = 3) or clinical and imaging follow-up for at least 12 months (n = 31). Results: At of the time of CEUS, the 59 nodules were diagnosed as HCC in 26 and benign lesions in 33, including 20 regenerative/dysplastic nodules (RN/DN), 11 hemangiomas, and 2 focal fat sparing. All 26 nodules with arterial phase hypervascularity without hemangioma-like features were HCC. However, CEUS misdiagnosed HCC as RN/DN in 4 cases with arterial iso- (n = 3) or hypovascularity (n = 1). CEUS correctly diagnosed all 11 hemangiomas. The sensitivity, specificity, and accuracy of CEUS for diagnosing HCC were 86.7, 100, and 93.2%. Conclusions: Arterial phase vascular intensity and pattern of CEUS are highly accurate for the diagnosis of small (1-2 cm) HCC and hemangioma in liver cirrhosis. On CEUS, arterial phase hypervascularity without a hemangioma-pattern alone may be sufficient for diagnosis of small HCC. Infrequent iso/hypovascular HCC may erroneously suggest RN/DN necessitating biopsy or close follow-up.

  10. Post-operative monitoring of tissue transfers: advantages using contrast enhanced ultrasound (CEUS) and contrast enhanced MRI (ceMRI) with dynamic perfusion analysis?

    Science.gov (United States)

    Lamby, P; Prantl, L; Fellner, C; Geis, S; Jung, E M

    2011-01-01

    The immediate evaluation of microvascular tissue flaps with respect to microcirculation after transplantation is crucial for optimal monitoring and outcome. The purpose of our investigation was to evaluate the clinical value of contrast-enhanced ultrasound (CEUS) and contrast-enhanced MRI (ceMRI) for monitoring the integrity of tissue flaps in plastic surgery. To this end, we investigated 10 patients (47 ± 16 a) between postoperative day 7 and 14 who underwent flap surgery in order to cover tissue defects in various body regions. For CEUS we utilized the GE LOGIQ E9 equipped with a linear transducer (6-9 MHz). After application of 2.4 ml SonoVue, the tissue perfusion was detected in Low MI-Technique (MI present, both technologies provide an optimal assessment of perfusion in cutaneous, subcutaneous and muscle tissue layers, whereby the detection of fatty tissue perfusion is currently more easily detected using CEUS compared to ceMRI.

  11. Contrast-enhanced flair imaging in the evaluation of infectious leptomeningeal diseases

    International Nuclear Information System (INIS)

    Parmar, Hemant; Sitoh, Y.-Y.; Anand, Pooja; Chua, Violet; Hui, Francis

    2006-01-01

    Purpose: The purpose of our study was to compare contrast-enhanced fluid-attenuated inversion recovery (FLAIR) images with contrast-enhanced T1 weighted images for infectious leptomeningitis. Materials and methods: We studied twenty-four patients with a clinical suspicion of infectious meningitis with unenhanced FLAIR, contrast-enhanced T1 weighted and contrast-enhanced FLAIR MR sequences. Twelve patients had cytologic and biochemical diagnosis of meningitis on cerebrospinal fluid (CSF) examination obtained 48 h before or after the MR study. Sequences were considered positive if abnormal signal was seen in the subarachnoid space (cistern or sulci) or along pial surface. Results: Twenty-seven examinations in 24 patients were performed. Of the 12 patients (thirteen studies) in whom cytology was positive, unenhanced FLAIR images were positive in six cases (sensitivity 46%), contrast-enhanced FLAIR images were positive in 11 (sensitivity 85%), and contrast-enhanced T1 weighted MR images were positive in 11 patients (sensitivity 85%). Of the 12 patients (14 studies) in whom cerebrospinal fluid study was negative, unenhanced FLAIR images were negative in 13, contrast-enhanced FLAIR images were negative in 11, and contrast-enhanced T1 weighted MR images were negative in eight. Thus, the specificity of unenhanced FLAIR, contrast-enhanced FLAIR and contrast-enhanced T1 weighted images was 93, 79 and 57%, respectively. Conclusion: Our results suggest that post-contrast FLAIR images have similar sensitivity but a higher specificity compared to contrast-enhanced T1 weighted images for detection of leptomeningeal enhancement. It can be a useful adjunct to post-contrast T1 weighted images in evaluation of infectious leptomeningitis

  12. Contrast-enhanced flair imaging in the evaluation of infectious leptomeningeal diseases

    Energy Technology Data Exchange (ETDEWEB)

    Parmar, Hemant [Department of Neuroradiology, National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore 308433 (Singapore) and Department of Diagnostic Imaging, Hospital for Sick Children, Toronto (Canada)]. E-mail: parurad@hotmail.com; Sitoh, Y.-Y. [Department of Neuroradiology, National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore 308433 (Singapore); Anand, Pooja [Department of Neurology, National Neuroscience Institute, 11 Jalan Tan Tock Seng (Singapore); Chua, Violet [Department of Neuroradiology, National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore 308433 (Singapore); Hui, Francis [Department of Neuroradiology, National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore 308433 (Singapore)

    2006-04-15

    Purpose: The purpose of our study was to compare contrast-enhanced fluid-attenuated inversion recovery (FLAIR) images with contrast-enhanced T1 weighted images for infectious leptomeningitis. Materials and methods: We studied twenty-four patients with a clinical suspicion of infectious meningitis with unenhanced FLAIR, contrast-enhanced T1 weighted and contrast-enhanced FLAIR MR sequences. Twelve patients had cytologic and biochemical diagnosis of meningitis on cerebrospinal fluid (CSF) examination obtained 48 h before or after the MR study. Sequences were considered positive if abnormal signal was seen in the subarachnoid space (cistern or sulci) or along pial surface. Results: Twenty-seven examinations in 24 patients were performed. Of the 12 patients (thirteen studies) in whom cytology was positive, unenhanced FLAIR images were positive in six cases (sensitivity 46%), contrast-enhanced FLAIR images were positive in 11 (sensitivity 85%), and contrast-enhanced T1 weighted MR images were positive in 11 patients (sensitivity 85%). Of the 12 patients (14 studies) in whom cerebrospinal fluid study was negative, unenhanced FLAIR images were negative in 13, contrast-enhanced FLAIR images were negative in 11, and contrast-enhanced T1 weighted MR images were negative in eight. Thus, the specificity of unenhanced FLAIR, contrast-enhanced FLAIR and contrast-enhanced T1 weighted images was 93, 79 and 57%, respectively. Conclusion: Our results suggest that post-contrast FLAIR images have similar sensitivity but a higher specificity compared to contrast-enhanced T1 weighted images for detection of leptomeningeal enhancement. It can be a useful adjunct to post-contrast T1 weighted images in evaluation of infectious leptomeningitis.

  13. An improved contrast enhancement algorithm for infrared images based on adaptive double plateaus histogram equalization

    Science.gov (United States)

    Li, Shuo; Jin, Weiqi; Li, Li; Li, Yiyang

    2018-05-01

    Infrared thermal images can reflect the thermal-radiation distribution of a particular scene. However, the contrast of the infrared images is usually low. Hence, it is generally necessary to enhance the contrast of infrared images in advance to facilitate subsequent recognition and analysis. Based on the adaptive double plateaus histogram equalization, this paper presents an improved contrast enhancement algorithm for infrared thermal images. In the proposed algorithm, the normalized coefficient of variation of the histogram, which characterizes the level of contrast enhancement, is introduced as feedback information to adjust the upper and lower plateau thresholds. The experiments on actual infrared images show that compared to the three typical contrast-enhancement algorithms, the proposed algorithm has better scene adaptability and yields better contrast-enhancement results for infrared images with more dark areas or a higher dynamic range. Hence, it has high application value in contrast enhancement, dynamic range compression, and digital detail enhancement for infrared thermal images.

  14. Do Anesthetic Techniques Influence the Threshold for Glomerular Capillary Hemorrhage Induced in Rats by Contrast-Enhanced Diagnostic Ultrasound?

    Science.gov (United States)

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

    2016-02-01

    Glomerular capillary hemorrhage can be induced by ultrasonic cavitation during contrast-enhanced diagnostic ultrasound (US) exposure, an important nonthermal US bioeffect. Recent studies of pulmonary US exposure have shown that thresholds for another nonthermal bioeffect of US, pulmonary capillary hemorrhage, is strongly influenced by whether xylazine is included in the specific anesthetic technique. The objective of this study was to determine the influence of xylazine on contrast-enhanced diagnostic US-induced glomerular capillary hemorrhage. In this study, anesthesia with ketamine only was compared to ketamine plus xylazine for induction of glomerular capillary hemorrhage in rats by 1.6-MHz intermittent diagnostic US with a microsphere contrast agent (similar to Definity; Lantheus Medical Imaging, Inc, North Billerica, MA). Glomerular capillary hemorrhage was measured as a percentage of glomeruli with hemorrhage found in histologic sections for groups of rats scanned at different peak rarefactional pressure amplitudes. There was a significant difference between the magnitude of the glomerular capillary hemorrhage between the anesthetics at 2.3 MPa, with 45.6% hemorrhage for ketamine only, increasing to 63.2% hemorrhage for ketamine plus xylazine (P Ultrasound in Medicine.

  15. Diagnostic accuracy of contrast-enhanced ultrasound for the differential diagnosis of hepatocellular carcinoma: ESCULAP versus CEUS-LI-RADS.

    Science.gov (United States)

    Schellhaas, Barbara; Görtz, Ruediger S; Pfeifer, Lukas; Kielisch, Christian; Neurath, Markus F; Strobel, Deike

    2017-09-01

    A comparison is made of two contrast-enhanced ultrasound (CEUS) algorithms for the diagnosis of hepatocellular carcinoma (HCC) in high-risk patients: Erlanger Synopsis of Contrast-enhanced Ultrasound for Liver lesion Assessment in Patients at Risk (ESCULAP) and American College of Radiology Contrast-Enhanced Ultrasound-Liver Imaging Reporting and Data System (ACR-CEUS-LI-RADSv.2016). Focal liver lesions in 100 high-risk patients were assessed using both CEUS algorithms (ESCULAP and CEUS-LI-RADSv.2016) for a direct comparison. Lesions were categorized according to size and contrast enhancement in the arterial, portal venous and late phases.For the definite diagnosis of HCC, categories ESCULAP-4, ESCULAP-Tr and ESCULAP-V and CEUS-LI-RADS-LR-5, LR-Tr and LR-5-V were compared. In addition, CEUS-LI-RADS-category LR-M (definitely/probably malignant, but not specific for HCC) and ESCULAP-category C [intrahepatic cholangiocellular carcinoma (ICC)] were compared.Histology, CE-computed tomography and CE-MRI served as reference standards. The reference standard among 100 lesions included 87 HCCs, six ICCs and seven non-HCC-non-ICC-lesions. For the diagnosis of HCC, the diagnostic accuracy of CEUS was significantly higher with ESCULAP versus CEUS-LI-RADS (94.3%/72.4%; pdiagnostic accuracy for ICC (LR-M/ESCULAP-C) was identical with both algorithms (50%), with higher PPV for ESCULAP-C versus LR-M (75 vs. 50%). CEUS-based algorithms contribute toward standardized assessment and reporting of HCC-suspect lesions in high-risk patients. ESCULAP shows significantly higher diagnostic accuracy, sensitivity and negative predictive value with no loss of specificity compared with CEUS-LI-RADS. Both algorithms have an excellent PPV. Arterial hyperenhancement is the key feature for the diagnosis of HCC with CEUS. Washout should not be a necessary prerequisite for the diagnosis of definite HCC. CEUS-LI-RADS in its current version is inferior to ESCULAP for the noninvasive diagnosis of HCC

  16. Perfusion quantification in contrast-enhanced ultrasound (CEUS)--ready for research projects and routine clinical use.

    Science.gov (United States)

    Tranquart, F; Mercier, L; Frinking, P; Gaud, E; Arditi, M

    2012-07-01

    With contrast-enhanced ultrasound (CEUS) now established as a valuable imaging modality for many applications, a more specific demand has recently emerged for quantifying perfusion and using measured parameters as objective indicators for various disease states. However, CEUS perfusion quantification remains challenging and is not well integrated in daily clinical practice. The development of VueBox™ alleviates existing limitations and enables quantification in a standardized way. VueBox™ operates as an off-line software application, after dynamic contrast-enhanced ultrasound (DCE-US) is performed. It enables linearization of DICOM clips, assessment of perfusion using patented curve-fitting models, and generation of parametric images by synthesizing perfusion information at the pixel level using color coding. VueBox™ is compatible with most of the available ultrasound platforms (nonlinear contrast-enabled), has the ability to process both bolus and disruption-replenishment kinetics loops, allows analysis results and their context to be saved, and generates analysis reports automatically. Specific features have been added to VueBox™, such as fully automatic in-plane motion compensation and an easy-to-use clip editor. Processing time has been reduced as a result of parallel programming optimized for multi-core processors. A long list of perfusion parameters is available for each of the two administration modes to address all possible demands currently reported in the literature for diagnosis or treatment monitoring. In conclusion, VueBox™ is a valid and robust quantification tool to be used for standardizing perfusion quantification and to improve the reproducibility of results across centers. © Georg Thieme Verlag KG Stuttgart · New York.

  17. Indeterminate solid hepatic lesions identified on non-diagnostic contrast-enhanced computed tomography: Assessment of the additional diagnostic value of contrast-enhanced ultrasound in the non-cirrhotic liver

    International Nuclear Information System (INIS)

    Quaia, Emilio; De Paoli, Luca; Angileri, Roberta; Cabibbo, Biagio; Cova, Maria Assunta

    2014-01-01

    Objective: To assess the additional diagnostic value of contrast-enhanced ultrasound (CEUS) in the characterization of indeterminate solid hepatic lesions identified on non-diagnostic contrast-enhanced computed tomography (CT). Methods: Fifty-five solid hepatic lesions (1–4 cm in diameter) in 46 non-cirrhotic patients (26 female, 20 male; age ± SD, 55 ± 10 years) underwent CEUS after being detected on contrast-enhanced CT which was considered as non-diagnostic after on-site analysis. Two blinded independent readers assessed CT and CEUS scans and were asked to classify retrospectively each lesion as a malignant or benign based on reference diagnostic criteria for the different hepatic lesion histotypes. Diagnostic accuracy and confidence (area – A z – under ROC curve) were assessed by using gadobenate dimeglumine-enhanced magnetic resonance (MR) imaging (n = 30 lesions), histology (n = 7 lesions), or US follow-up (n = 18 lesions) as the reference standards. Results: Final diagnoses included 29 hemangiomas, 3 focal nodular hyperplasias, 1 hepatocellular adenoma, and 22 metastases. The additional review of CEUS after CT images improved significantly (P < .05) the diagnostic accuracy (before vs after CEUS review = 49% [20/55] vs 89% [49/55] – reader 1 and 43% [24/55] vs 92% [51/55] – reader 2) and confidence (A z , 95% Confidence Intervals before vs after CEUS review = .773 [.652–.895] vs .997 [.987–1] – reader 1 and .831 [.724–.938] vs .998 [.992–1] – reader 2). Conclusions: CEUS improved the characterization of indeterminate solid hepatic lesions identified on non-diagnostic contrast-enhanced CT by identifying some specific contrast enhancement patterns.

  18. Therapeutic response assessment of high intensity focused ultrasound therapy for uterine fibroid: Utility of contrast-enhanced ultrasonography

    International Nuclear Information System (INIS)

    Zhou Xiaodong; Ren Xiaolong; Zhang Jun; He Guangbin; Zheng Minjuan; Tian Xue; Li Li; Zhu Ting; Zhang Min; Wang Lei; Luo Wen

    2007-01-01

    Purpose: To assess the utility of contrast-enhanced ultrasonography (ceUS) in the assessment of the therapeutic response to high intensity focused ultrasound (HIFU) ablation in patients with uterine fibroid. Materials and methods: Sixty-four patients with a total of 64 uterine fibroids (mean: 5.3 ± 1.2 cm; range: 3.2-8.9 cm) treated with HIFU ablation under the ultrasound guidance were evaluated with ceUS after receiving an intravenous bolus injection of a microbubble contrast agent (SonoVue) within 1 week after intervention. We obtained serial ceUS images during the time period from beginning to 5 min after the initiation of the bolus contrast injection. All of the patients underwent a contrast enhanced MRI (ceMRI) and ultrasound guided needle puncture biopsy within 1 week after HIFU ablation. And as a follow-up, all of the patients underwent US at 1, 3, 6 and 12 months after HIFU treatment. The volume change was observed and compared to pre- and post-HIFU ablation. The results of the ceUS were compared with those of the ceMRI in terms of the presence or absence of residual unablated tumor and pathologic change in the treated lesions. Results: On ceUS, diagnostic accuracy was 100%, while residual unablated tumors were found in three uterine fibroids (4.7%) and failed treatment was found in eight uterine fibroids (12.5%). All the 11 fibroids were subjected to additional HIFU ablation. Of the 58 ablated fibroids without residual tumors on both the ceUS and ceMRI after the HIFU ablation, the volumes of all the fibroids decreased in different degrees during the 1 year follow-up USs. And histologic examinations confirmed findings of necrotic and viable tumor tissue, respectively. Conclusion: CEUS is potentially useful for evaluating the early therapeutic effect of percutaneous HIFU ablation for uterine fibroids

  19. Assessment of renal perfusion with contrast-enhanced ultrasound: Preliminary results in early diabetic nephropathies.

    Science.gov (United States)

    Dong, Yi; Wang, Wen-Ping; Lin, Pan; Fan, Peili; Mao, Feng

    2016-01-01

    We performed a prospective study to evaluate the value of contrast-enhanced ultrasound (CEUS) in quantitative evaluation of renal cortex perfusion in patients suspected of early diabetic nephropathies (DN), with the estimated GFR (MDRD equation) as the gold standard. The study protocol was approved by the hospital review board; each patient gave written informed consent. Our study included 46 cases (21 males and 25 females, mean age 55.6 ± 4.14 years) of clinical confirmed early DN patients. After intravenous bolus injection of 1 ml sulfur hexafluoride microbubbles of ultrasound contrast agent, real time CEUS of renal cortex was performed successively using a 2-5 MHz convex probe. Time-intensity curves (TICs) and quantitative indexes were created with Qlab software. Receiver operating characteristic (ROC) curves were used to predict the diagnostic criteria of CEUS quantitative indexes, and their diagnostic efficiencies were compared with resistance index (RI) and peak systolic velocity (PSV) of renal segmental arteries by chi square test. Our control group included forty-five healthy volunteers. Difference was considered statistically significant with P  0.05). CEUS might be helpful to improve early diagnosis of DN by quantitative analyses. AUC and DPI might be valuable quantitative indexes.

  20. Contrast-Enhanced Ultrasound Guided Biopsy of Undetermined Abdominal Lesions: A Multidisciplinary Decision-Making Approach

    Directory of Open Access Journals (Sweden)

    Feng Mao

    2017-01-01

    Full Text Available Aim. To investigate the value of contrast-enhanced ultrasound (CEUS guided biopsy of undetermined abdominal lesions in multidisciplinary treatment (MDT decision-making approach. Methods. Between Jan 2012 and Dec 2015, 60 consecutive patients (male, 37; female, 23; mean age, 51.3 years ± 14.6 who presented with undetermined abdominal lesions were included. CEUS and core needle percutaneous biopsy was performed under real-time CEUS guidance in all lesions. Data were recorded and compared with conventional ultrasound (US guidance group (n=75. All CEUS findings and clinical data were evaluated in MDT. Results. CEUS enabled the delimitation of more (88.3% versus 41.3% and larger (14.1 ± 10.7 mm versus 32.3 ± 18.5 mm nonenhanced necrotic areas. More inner (20.0% versus 6.7% and surrounding (18.3% versus 2.7% major vessels were visualized and avoided during biopsies. CEUS-guided biopsy increased the diagnostic accuracy from 93.3% to 98.3%, with correct diagnosis in 57 of 60 lesions (95.0%. The therapeutic plan was influenced by CEUS guided biopsies findings in the majority of patients (98.3%. Conclusion. The combination of CEUS guided biopsy and MDT decision-making approach is useful in the diagnostic work-up and therapeutic management.

  1. Contrast-Enhanced Ultrasound Guided Biopsy of Undetermined Abdominal Lesions: A Multidisciplinary Decision-Making Approach.

    Science.gov (United States)

    Mao, Feng; Dong, Yi; Ji, Zhengbiao; Cao, Jiaying; Wang, Wen-Ping

    2017-01-01

    Aim. To investigate the value of contrast-enhanced ultrasound (CEUS) guided biopsy of undetermined abdominal lesions in multidisciplinary treatment (MDT) decision-making approach. Methods. Between Jan 2012 and Dec 2015, 60 consecutive patients (male, 37; female, 23; mean age, 51.3 years ± 14.6) who presented with undetermined abdominal lesions were included. CEUS and core needle percutaneous biopsy was performed under real-time CEUS guidance in all lesions. Data were recorded and compared with conventional ultrasound (US) guidance group ( n = 75). All CEUS findings and clinical data were evaluated in MDT. Results. CEUS enabled the delimitation of more (88.3% versus 41.3%) and larger (14.1 ± 10.7 mm versus 32.3 ± 18.5 mm) nonenhanced necrotic areas. More inner (20.0% versus 6.7%) and surrounding (18.3% versus 2.7%) major vessels were visualized and avoided during biopsies. CEUS-guided biopsy increased the diagnostic accuracy from 93.3% to 98.3%, with correct diagnosis in 57 of 60 lesions (95.0%). The therapeutic plan was influenced by CEUS guided biopsies findings in the majority of patients (98.3%). Conclusion. The combination of CEUS guided biopsy and MDT decision-making approach is useful in the diagnostic work-up and therapeutic management.

  2. Applicability of contrast-enhanced ultrasound in the diagnosis of plantar fasciitis.

    Science.gov (United States)

    Broholm, R; Pingel, J; Simonsen, L; Bülow, J; Johannsen, F

    2017-12-01

    Contrast-enhanced ultrasound (CEUS) is used to visualize the microvascularization in various tissues. The purpose of this study was to investigate whether CEUS could be used to visualize the microvascular volume (MV) in the plantar fascia, and to compare the method to clinical symptoms and B-mode ultrasound (US) in patients with plantar fasciitis (PF). Twenty patients with unilateral PF were included and were divided by US in insertional thickening (10), midsubstance thickening (5), and no US changes (5). The MV was measured simultaneously in both heels. Four areas in the plantar fascia and plantar fat pad were measured independently by two observers. Inter- and intra-observer correlation analyses were performed. The asymptomatic heels showed a constantly low MV, and for the whole group of patients, a significantly higher MV was found in the symptomatic plantar fascia and plantar fat pad. Inter-observer correlation as well as intra-observer agreement was excellent. The MV in the plantar fascia and plantar fat pad can be measured reliably using CEUS, suggesting that it is a reproducible method to examine patients with plantar fasciitis. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. Appropriate Contrast Enhancement Measures for Brain and Breast Cancer Images

    Directory of Open Access Journals (Sweden)

    Suneet Gupta

    2016-01-01

    Full Text Available Medical imaging systems often produce images that require enhancement, such as improving the image contrast as they are poor in contrast. Therefore, they must be enhanced before they are examined by medical professionals. This is necessary for proper diagnosis and subsequent treatment. We do have various enhancement algorithms which enhance the medical images to different extents. We also have various quantitative metrics or measures which evaluate the quality of an image. This paper suggests the most appropriate measures for two of the medical images, namely, brain cancer images and breast cancer images.

  4. Temporal contrast enhancement and parametric imaging for the visualisation of time patterns in dynamic scintigraphic imaging

    International Nuclear Information System (INIS)

    Deconinck, F.; Bossuyt, A.; Lepoudre, R.

    1982-01-01

    Image contrast, photon noise and sampling frequency limit the visual extraction of relevant temporal information in scintigraphic image series. When the Unitation is mainly due to low temporal contrast, temporal contrast enhancement will strongly improve the perceptibility of time patterns in the series. When the limitation is due to photon noise and limited temporal sampling, parametric imaging by means of the Hadamard transform can visualise temporal patterns. (WU)

  5. Pulse sequences for contrast-enhanced magnetic resonance imaging

    International Nuclear Information System (INIS)

    Graves, Martin J.

    2007-01-01

    The theory and application of magnetic resonance imaging (MRI) pulse sequences following the administration of an exogenous contrast agent are discussed. Pulse sequences are categorised according to the contrast agent mechanism: changes in proton density, relaxivity, magnetic susceptibility and resonant frequency shift. Applications in morphological imaging, magnetic resonance angiography, dynamic imaging and cell labelling are described. The importance of optimising the pulse sequence for each application is emphasised

  6. Microbubbles in macrocysts - Contrast-enhanced ultrasound assisted sclerosant therapy of a congenital macrocystic lymphangioma: a case report.

    Science.gov (United States)

    Menendez-Castro, Carlos; Zapke, Maren; Fahlbusch, Fabian; von Goessel, Heiko; Rascher, Wolfgang; Jüngert, Jörg

    2017-07-06

    Congenital cystic lymphangiomas are benign malformations due to a developmental disorder of lymphatic vessels. Besides surgical excision, sclerosant therapy of these lesions by intracavitary injection of OK-432 (Picibanil®), a lyophilized mixture of group A Streptococcus pyogenes, is a common therapeutical option. For an appropriate application of OK-432, a detailed knowledge about the structure and composition of the congenital cystic lymphangioma is essential. SonoVue® is a commercially available contrast agent commonly used in sonography by intravenous and intracavitary application. Here we report the case of 2 month old male patient with a large thoracic congenital cystic lymphangioma. Preinterventional imaging of the malformation was performed by contrast-enhanced ultrasound after intracavitary application of SonoVue® immediately followed by a successful sclerotherapy with OK-432. Contrast agent-enhanced ultrasound imaging offers a valuable option to preinterventionally clarify the anatomic specifications of a congenital cystic lymphangioma in more detail than by single conventional sonography. By the exact knowledge about the composition and especially about the intercystic communications of the lymphangioma sclerosant therapy becomes safer and more efficient.

  7. Therapeutic response assessment of percutaneous radiofrequency ablation for hepatocellular carcinoma: Utility of contrast-enhanced agent detection imaging

    International Nuclear Information System (INIS)

    Kim, Chan Kyo; Choi, Dongil; Lim, Hyo K.; Kim, Seung Hoon; Lee, Won Jae; Kim, Min Ju; Lee, Ji Yeon; Jeon, Yong Hwan; Lee, Jongmee; Lee, Soon Jin; Lim, Jae Hoon

    2005-01-01

    Purpose: To assess the utility of contrast-enhanced agent detection imaging (ADI) in the assessment of the therapeutic response to percutaneous radiofrequency (RF) ablation in patients with hepatocellular carcinoma (HCC). Materials and methods: Ninety patients with a total of 97 nodular HCCs (mean, 2.1 ± 1.3 cm; range, 1.0-5.0 cm) treated with percutaneous RF ablation under the ultrasound guidance were evaluated with contrast-enhanced ADI after receiving an intravenous bolus injection of a microbubble contrast agent (SH U 508A). We obtained serial contrast-enhanced ADI images during the time period from 15 to 90 s after the initiation of the bolus contrast injection. All of the patients underwent a follow-up four-phase helical CT at 1 month after RF ablation, which was then repeated at 2-4 month intervals during a period of at least 12 months. The results of the contrast-enhanced ADI were compared with those of the follow-up CT in terms of the presence or absence of residual unablated tumor and local tumor progression in the treated lesions. Results: On contrast-enhanced ADI, technical success was obtained in 94 (97%) of the 97 HCCs, while residual unablated tumors were found in three HCCs (3%). Two of the three tumors that were suspicious (was not proven) for incomplete ablation were subjected to additional RF ablation. The remaining one enhancing lesion that was suspicious of a residual tumor on contrast-enhanced ADI was revealed to be reactive hyperemia at the 1-month follow-up CT. Therefore; the diagnostic concordance between the contrast-enhanced ADI and 1-month follow-up CT was 99%. Of the 94 ablated HCCs without residual tumors on both the contrast-enhanced ADI and 1-month follow-up CT after the initial RF ablation, five (5%) had CT findings of local tumor progression at a subsequent follow-up CT. Conclusion: Despite its limitations in predicting local tumor progression in the treated tumors, contrast-enhanced ADI is potentially useful for evaluating the

  8. A developed unsharp masking method for images contrast enhancement

    International Nuclear Information System (INIS)

    Zaafouri, A.; Sayadi, M.; Fnaiech, F.

    2011-01-01

    In this paper, we propose a developed unsharp masking process for contrast image enhancement. The main idea here is to enhance the dark and bright area in the same way which matches the response of human visual system well. Then in order to reduce the noise effect, a mean weighted high pass filter is used for edge extraction. The proposed method gives satisfactory results for wide range of low contrast images compared with others known approaches.

  9. Interobserver Variation of the Bolus-and-Burst Method for Pancreatic Perfusion with Dynamic – Contrast-Enhanced Ultrasound

    Czech Academy of Sciences Publication Activity Database

    Stangeland, M.; Engjom, T.; Mézl, M.; Jiřík, Radovan; Gilja, O.H.; Dimcevski, G.; Nylund, K.

    2017-01-01

    Roč. 3, č. 3 (2017), E99-E106 E-ISSN 2199-7152 Institutional support: RVO:68081731 Keywords : interobserver * dynamic contrast-enhanced ultrasound * perfusion * pancreas Subject RIV: BH - Optics, Masers, Lasers OBOR OECD: Medical engineering https://www.thieme-connect.com/products/ejournals/abstract/10.1055/s-0043-110475

  10. Evaluation of breast lesions by contrast enhanced ultrasound: Qualitative and quantitative analysis

    International Nuclear Information System (INIS)

    Wan Caifeng; Du Jing; Fang Hua; Li Fenghua; Wang Lin

    2012-01-01

    Objective: To evaluate and compare the diagnostic performance of qualitative, quantitative and combined analysis for characterization of breast lesions in contrast enhanced ultrasound (CEUS), with histological results used as the reference standard. Methods: Ninety-one patients with 91 breast lesions BI-RADS 3–5 at US or mammography underwent CEUS. All lesions underwent qualitative and quantitative enhancement evaluation. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic performance of different analytical method for discrimination between benign and malignant breast lesions. Results: Histopathologic analysis of the 91 lesions revealed 44 benign and 47 malignant. For qualitative analysis, benign and malignant lesions differ significantly in enhancement patterns (p z1 ), 0.768 (A z2 ) and 0.926(A z3 ) respectively. The values of A z1 and A z3 were significantly higher than that for A z2 (p = 0.024 and p = 0.008, respectively). But there was no significant difference between the values of A z1 and A z3 (p = 0.625). Conclusions: The diagnostic performance of qualitative and combined analysis was significantly higher than that for quantitative analysis. Although quantitative analysis has the potential to differentiate benign from malignant lesions, it has not yet improved the final diagnostic accuracy.

  11. Contrast-enhanced ultrasound of focal nodular hyperplasia: a matter of size

    Energy Technology Data Exchange (ETDEWEB)

    Bertin, Caroline [Hopital Beaujon APHP, Radiology Department, Clichy (France); Egels, Sophie; Huynh-Charlier, Isabelle [Hopital Pitie-Salpetriere APHP, Radiology Department, Paris (France); Wagner, Mathilde [Hopital Pitie-Salpetriere APHP, Radiology Department, Paris (France); Universite Paris Diderot, INSERM, UMR 1149, Laboratoire IPMA, Centre de Recherche sur l' Inflammation, Faculte de Medecine X Bichat, Paris (France); Vilgrain, Valerie [Hopital Beaujon APHP, Radiology Department, Clichy (France); Universite Paris Diderot, INSERM, UMR 1149, Laboratoire IPMA, Centre de Recherche sur l' Inflammation, Faculte de Medecine X Bichat, Paris (France); Lucidarme, Olivier [Hopital Pitie-Salpetriere APHP, Radiology Department, Paris (France); Sorbonne Universites, UPMC Univ Paris 06, CNRS UMR 7371, INSERM UMRS 1146, Laboratoire d' Imagerie Biomedicale, Paris (France); Groupe Hospitalier Pitie-Salpetriere - Charles Foix, Service de Radiologie Polyvalente et Oncologique, Paris (France)

    2014-10-15

    To assess the contrast-enhanced ultrasound (CEUS) frequencies of centrifugal enhancement, spoke-wheel sign and central scar in focal nodular hyperplasia (FNH) as a function of lesion size. Ninety-four FNHs were retrospectively reviewed to assess their largest diameter and enhancement pattern, including centrifugal enhancement from one central artery, spoke-wheel sign, diffuse or centripetal enhancement, central scar and late-phase washout. Mean FNH-lesion size was 3.7 ± 2.1 cm. Only 43.6 % of FNHs had centrifugal enhancement, with a spoke-wheel pattern (23.4 %) or without (20.2 %), while 56.4 % showed diffuse or centripetal enhancement. Centrifugal enhancement was observed in 73.9 % of FNHs ≤3.1 cm and 14.6 % of FNHs >3.1 cm (P < 10{sup -4}). Size and frequency of centrifugal enhancement were negatively correlated (r = -0.57, P < 10{sup -4}). The spoke-wheel pattern was also seen more frequently in smaller (37 %) than in larger FNHs (10.4 %) (P < 10{sup -3}). Late-phase washout was described in 5.3 % of FNHs and was not size-dependent. Lesions with a central scar were larger than those without, respectively, 5.7 ± 1.7 and 3.6 ± 2.0 cm (P = 0.012). Typical centrifugal enhancement yielding a confident FNH diagnosis is seen significantly more frequently when the lesion is ≤3.1 cm. (orig.)

  12. Differential diagnosis of gastric cancer and gastritis: the role of contrast-enhanced ultrasound (CEUS).

    Science.gov (United States)

    Xue, Heng; Ge, Hui-Yu; Miao, Li-Ying; Wang, Shu-Min; Zhao, Bo; Wang, Jin-Rui; Cui, Li-Gang

    2017-03-01

    To evaluate the diagnostic performance of contrast-enhanced ultrasound (CEUS) in differential diagnosis of gastric cancer and gastritis, with histological results as reference standard. From September 2011 to August 2014, 82 patients (50 males and 32 females; mean age ± SD, 59.5 ± 15.0 years; range 19-91 years) with gastric cancer or gastritis were included in this Ethics Committee-approved prospective study. Conventional ultrasonography (US) and CEUS were applied to distinguish the two lesions, and both qualitative and quantitative features were evaluated. Of the 82 histopathologic-proven lesions, 58 were cancer and 24 were gastritis. For US, the gastric wall stratification was not preserved in about one-third of cancer (21/58, 36.2%) compared with gastritis (0/24, 0%) (p gastritis (19/24, 79.2%, p gastritis. CEUS has the potential to make the diagnosis more accurate.

  13. Influence of ageing on quantitative contrast-enhanced ultrasound of the kidneys in healthy cats.

    Science.gov (United States)

    Stock, Emmelie; Paepe, Dominique; Daminet, Sylvie; Duchateau, Luc; Saunders, Jimmy H; Vanderperren, Katrien

    2018-05-05

    The degenerative effects of ageing on the kidneys have been extensively studied in humans. However, only recently interest has been focused on renal ageing in veterinary medicine. Contrast-enhanced ultrasound allows non-invasive evaluation of renal perfusion in conscious cats. Renal perfusion parameters were obtained in 43 healthy cats aged 1-16 years old, and the cats were divided in four age categories: 1-3 years, 3-6 years, 6-10 years and over 10 years. Routine renal parameters as serum creatinine, serum urea, urine-specific gravity, urinary protein:creatinine ratio and systolic blood pressure were also measured. No significant differences in any of the perfusion parameters were observed among the different age categories. A trend towards a lower peak enhancement and wash-in area under the curve with increasing age, suggestive for a lower blood volume, was detected when comparing the cats over 10 years old with the cats of 1-3 years old. Additionally, no significant age-effect was observed for the serum and urine parameters, whereas a higher blood pressure was observed in healthy cats over 10 years old. © British Veterinary Association (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  14. Contrast enhancement in EIT imaging of the brain

    International Nuclear Information System (INIS)

    Nissinen, A; Kaipio, J P; Vauhkonen, M; Kolehmainen, V

    2016-01-01

    We consider electrical impedance tomography (EIT) imaging of the brain. The brain is surrounded by the poorly conducting skull which has low conductivity compared to the brain. The skull layer causes a partial shielding effect which leads to weak sensitivity for the imaging of the brain tissue. In this paper we propose an approach based on the Bayesian approximation error approach, to enhance the contrast in brain imaging. With this approach, both the (uninteresting) geometry and the conductivity of the skull are embedded in the approximation error statistics, which leads to a computationally efficient algorithm that is able to detect features such as internal haemorrhage with significantly increased sensitivity and specificity. We evaluate the approach with simulations and phantom data. (paper)

  15. Contrast enhancement in EIT imaging of the brain.

    Science.gov (United States)

    Nissinen, A; Kaipio, J P; Vauhkonen, M; Kolehmainen, V

    2016-01-01

    We consider electrical impedance tomography (EIT) imaging of the brain. The brain is surrounded by the poorly conducting skull which has low conductivity compared to the brain. The skull layer causes a partial shielding effect which leads to weak sensitivity for the imaging of the brain tissue. In this paper we propose an approach based on the Bayesian approximation error approach, to enhance the contrast in brain imaging. With this approach, both the (uninteresting) geometry and the conductivity of the skull are embedded in the approximation error statistics, which leads to a computationally efficient algorithm that is able to detect features such as internal haemorrhage with significantly increased sensitivity and specificity. We evaluate the approach with simulations and phantom data.

  16. Detection of vascularity in wrist tenosynovitis: power doppler ultrasound compared with contrast-enhanced grey-scale ultrasound.

    Science.gov (United States)

    Klauser, Andrea S; Franz, Magdalena; Arora, Rohit; Feuchtner, Gudrun M; Gruber, Johann; Schirmer, Michael; Jaschke, Werner R; Gabl, Markus F

    2010-01-01

    We sought to assess vascularity in wrist tenosynovitis by using power Doppler ultrasound (PDUS) and to compare detection of intra- and peritendinous vascularity with that of contrast-enhanced grey-scale ultrasound (CEUS). Twenty-six tendons of 24 patients (nine men, 15 women; mean age ± SD, 54.4 ± 11.8 years) with a clinical diagnosis of tenosynovitis were examined with B-mode ultrasonography, PDUS, and CEUS by using a second-generation contrast agent, SonoVue (Bracco Diagnostics, Milan, Italy) and a low-mechanical-index ultrasound technique. Thickness of synovitis, extent of vascularized pannus, intensity of peritendinous vascularisation, and detection of intratendinous vessels was incorporated in a 3-score grading system (grade 0 to 2). Interobserver variability was calculated. With CEUS, a significantly greater extent of vascularity could be detected than by using PDUS (P < 0.001). In terms of peri- and intratendinous vessels, CEUS was significantly more sensitive in the detection of vascularization compared with PDUS (P < 0.001). No significant correlation between synovial thickening and extent of vascularity could be found (P = 0.089 to 0.097). Interobserver reliability was calculated to be excellent when evaluating the grading score (κ = 0.811 to 1.00). CEUS is a promising tool to detect tendon vascularity with higher sensitivity than PDUS by improved detection of intra- and peritendinous vascularity.

  17. Contrast-enhanced ultrasound-guided radiofrequency ablation in inconspicuous hepatocellular carcinoma on B-mode ultrasound.

    Science.gov (United States)

    Kim, Eui Joo; Kim, Yun Soo; Shin, Seung Kak; Kwon, Oh Sang; Choi, Duck Joo; Kim, Ju Hyun

    2017-11-01

    B-mode ultrasound (US) has difficulty targeting small hepatocellular carcinomas (HCCs) with poor conspicuity during radiofrequency ablation (RFA). Contrast-enhanced ultrasound (CEUS) can improve visualization of small or inconspicuous HCCs. This study was conducted to evaluate the effectiveness of CEUS-guided RFA electrode insertion during the arterial phase in inconspicuous HCCs. Ninety-three treatment-naïve HCCs from 80 patients treated with RFA from August 2012 to December 2014 were retrospectively reviewed. Seventy-five HCCs from 65 patients underwent B-mode US-guided RFA, and 15 HCCs from 14 patients that were inconspicuous on B-mode US underwent CEUS-guided RFA during the arterial phase after injection of sulfur hexafluoride microbubbles (SonoVue®). Technical success was assessed by contrast-enhanced computed tomography within 1 week and 3 months after the procedure. The mean size of HCCs treated with CEUS-guided RFA was smaller than that of HCCs treated with B-mode US-guided RFA (1.17±0.36 vs. 1.63±0.55 cm, p=0.003). Technical success rates of CEUS-guided RFA within 1 week and 3 months were 100% (15/15) and 93.3% (14/15), respectively. Technical success rates of B-mode US-guided RFA were 97.3% (73/75) and 94.5% (69/73), respectively. CEUS-guided RFA is highly efficacious for ablation of very small and inconspicuous HCCs.

  18. The role of contrast-enhanced ultrasonography in image-guided liver ablations

    International Nuclear Information System (INIS)

    Pescatori, Lorenzo Carlo; Sconfienza, Luca Maria; Mauri, Giovanni

    2016-01-01

    We read with great interest the paper by Kim et al. entitled “Local ablation therapy with contrast enhanced ultrasonography for hepatocellular carcinoma: a practical review,” recently published in Ultrasonography. We think that contrast-enhanced ultrasonography (CEUS), together with the development of reliable navigation systems, is likely to represent one of the most important advances in image-guided ablations in recent years. Thus, we offer some considerations on the topic

  19. Contrast-enhanced dynamic MR imaging in rheumatoid arthritis

    International Nuclear Information System (INIS)

    Koenig, H.; Sieper, J.; Wolf, K.J.

    1989-01-01

    This paper reports on a study for the identification of different pannus formations. Twenty patients with advanced rheumatoid arthritis of the knee joint were examined with MR imaging primary to surgery. The authors used a 1.5-T Magnetom unit, a circular surface coil for signal detection, 0.1 mmol/kg of Gd-DTPA given as a bolus injection, fast low-angle shot (FLASH) sequence (TR, 30 msec; TE, 10 msec; 128 x 128 matrix; excitation angle, 70 degrees) repeated 30 times within 120 seconds, and a T1-weighted spin-echo sequence (Tr, 500 msec; TE, 22 msec) before and 2 minutes after contrast medium injection. Enhancement of pannus and joint effusion has been measured and standardized to muscle tissue

  20. Contrast enhancement of the cochlear aqueduct in MR imaging: its frequency and clinical significance

    International Nuclear Information System (INIS)

    Nakamura, T.; Naganawa, S.; Fukatsu, H.; Sakurai, Y.; Ishigaki, T.; Aoki, I.; Ninomiya, A.; Nakashima, T.

    2003-01-01

    There have been no previous reports on contrast enhancement of the cochlear aqueduct in magnetic resonance imaging. The purpose of the present study was to evaluate the frequency and significance of this finding. Thirty-one patients (15 men and 16 women; age range 18-81 years) with otologic symptoms (sudden sensorineural hearing loss, vertigo, or tinnitus) were examined using contrast-enhanced imaging on a 1.5-T MR scanner. The normal ear served as the control. Two radiologists evaluated contrast enhancement in the area of the cochlear aqueduct. Forty-eight of 62 ears (77.4%) showed contrast enhancement of the cochlear aqueduct, but no significant differences in the frequency of contrast enhancement were observed between patients with and patients without vertigo, tinnitus, sensorineural hearing loss, cerebellopontine angle tumors, or a high-riding jugular bulb. In addition, no gender- or age-related differences were noted. Contrast enhancement of the cochlear aqueduct was frequently observed, but the frequency of enhancement in symptomatic ears was not significantly higher than in control ears. The results of this study may prove helpful in avoiding unnecessary examinations and potential diagnostic confusion. (orig.)

  1. Contrast enhancement of the cochlear aqueduct in MR imaging: its frequency and clinical significance

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, T; Naganawa, S; Fukatsu, H; Sakurai, Y; Ishigaki, T [Department of Radiology, Nagoya University School of Medicine, 65 Tsurumai-cho, 466-8550, Shouwa-ku, Nagoya (Japan); Aoki, I; Ninomiya, A [Medical Systems Company, Toshiba Corporation, Nasu Operations, Otawara-shi, Tochigi (Japan); Nakashima, T [Department of Otorhinolaryngology, Nagoya University School of Medicine, Shouwa-ku, Nagoya (Japan)

    2003-09-01

    There have been no previous reports on contrast enhancement of the cochlear aqueduct in magnetic resonance imaging. The purpose of the present study was to evaluate the frequency and significance of this finding. Thirty-one patients (15 men and 16 women; age range 18-81 years) with otologic symptoms (sudden sensorineural hearing loss, vertigo, or tinnitus) were examined using contrast-enhanced imaging on a 1.5-T MR scanner. The normal ear served as the control. Two radiologists evaluated contrast enhancement in the area of the cochlear aqueduct. Forty-eight of 62 ears (77.4%) showed contrast enhancement of the cochlear aqueduct, but no significant differences in the frequency of contrast enhancement were observed between patients with and patients without vertigo, tinnitus, sensorineural hearing loss, cerebellopontine angle tumors, or a high-riding jugular bulb. In addition, no gender- or age-related differences were noted. Contrast enhancement of the cochlear aqueduct was frequently observed, but the frequency of enhancement in symptomatic ears was not significantly higher than in control ears. The results of this study may prove helpful in avoiding unnecessary examinations and potential diagnostic confusion. (orig.)

  2. Diagnostic accuracy of magnetic resonance, computed tomography and contrast enhanced ultrasound in radiological multimodality assessment of peribiliary liver metastases.

    Directory of Open Access Journals (Sweden)

    Vincenza Granata

    Full Text Available We compared diagnostic performance of Magnetic Resonance (MR, Computed Tomography (CT and Ultrasound (US with (CEUS and without contrast medium to identify peribiliary metastasis.We identified 35 subjects with histological proven peribiliary metastases who underwent CEUS, CT and MR study. Four radiologists evaluated the presence of peribiliary lesions, using a 4-point confidence scale. Echogenicity, density and T1-Weigthed (T1-W, T2-W and Diffusion Weighted Imaging (DWI signal intensity as well as the enhancement pattern during contrast studies on CEUS, CT and MR so as hepatobiliary-phase on MRI was assessed.All lesions were detected by MR. CT detected 8 lesions, while US/CEUS detected one lesion. According to the site of the lesion, respect to the bile duct and hepatic parenchyma: 19 (54.3% were periductal, 15 (42.8% were intra-periductal and 1 (2.8% was periductal-intrahepatic. According to the confidence scale MRI had the best diagnostic performance to assess the lesion. CT obtained lower diagnostic performance. There was no significant difference in MR signal intensity and contrast enhancement among all metastases (p>0.05. There was no significant difference in CT density and contrast enhancement among all metastases (p>0.05.MRI is the method of choice for biliary tract tumors but it does not allow a correct differential diagnosis among different histological types of metastasis. The presence of biliary tree dilatation without hepatic lesions on CT and US/CEUS study may be an indirect sign of peribiliary metastases and for this reason the patient should be evaluated by MRI.

  3. Contrast-enhanced ultrasound vs multidetector-computed tomography for detecting liver metastases in colorectal cancer: a prospective, blinded, patient-by-patient analysis

    DEFF Research Database (Denmark)

    Rafaelsen, S R; Jakobsen, A

    2011-01-01

    This study compared the sensitivity and specificity of contrast-enhanced ultrasound (CEUS) and multidetector-computed tomography (MDCT) in the detection of liver metastases in patients with colorectal cancer.......This study compared the sensitivity and specificity of contrast-enhanced ultrasound (CEUS) and multidetector-computed tomography (MDCT) in the detection of liver metastases in patients with colorectal cancer....

  4. Medical Image Visual Appearance Improvement Using Bihistogram Bezier Curve Contrast Enhancement: Data from the Osteoarthritis Initiative

    Science.gov (United States)

    Gan, Hong-Seng; Swee, Tan Tian; Abdul Karim, Ahmad Helmy; Sayuti, Khairil Amir; Abdul Kadir, Mohammed Rafiq; Tham, Weng-Kit; Wong, Liang-Xuan; Chaudhary, Kashif T.; Yupapin, Preecha P.

    2014-01-01

    Well-defined image can assist user to identify region of interest during segmentation. However, complex medical image is usually characterized by poor tissue contrast and low background luminance. The contrast improvement can lift image visual quality, but the fundamental contrast enhancement methods often overlook the sudden jump problem. In this work, the proposed bihistogram Bezier curve contrast enhancement introduces the concept of “adequate contrast enhancement” to overcome sudden jump problem in knee magnetic resonance image. Since every image produces its own intensity distribution, the adequate contrast enhancement checks on the image's maximum intensity distortion and uses intensity discrepancy reduction to generate Bezier transform curve. The proposed method improves tissue contrast and preserves pertinent knee features without compromising natural image appearance. Besides, statistical results from Fisher's Least Significant Difference test and the Duncan test have consistently indicated that the proposed method outperforms fundamental contrast enhancement methods to exalt image visual quality. As the study is limited to relatively small image database, future works will include a larger dataset with osteoarthritic images to assess the clinical effectiveness of the proposed method to facilitate the image inspection. PMID:24977191

  5. Contrast-enhanced harmonic endoscopic ultrasound in solid lesions of the pancreas: results of a pilot study.

    Science.gov (United States)

    Napoleon, B; Alvarez-Sanchez, M V; Gincoul, R; Pujol, B; Lefort, C; Lepilliez, V; Labadie, M; Souquet, J C; Queneau, P E; Scoazec, J Y; Chayvialle, J A; Ponchon, T

    2010-07-01

    Distinguishing pancreatic adenocarcinoma from other pancreatic masses remains challenging with current imaging techniques. This prospective study aimed to evaluate the accuracy of a new procedure, imaging the microcirculation pattern of the pancreas by contrast-enhanced harmonic endoscopic ultrasound (CEH-EUS) with a new Olympus prototype echo endoscope. 35 patients presenting with solid pancreatic lesions were prospectively enrolled. All patients had conventional B mode and power Doppler EUS. After an intravenous bolus injection of 2.4 ml of a second-generation ultrasound contrast agent (SonoVue) CEH-EUS was then performed with a new Olympus prototype echo endoscope (xGF-UCT 180). The microvascular pattern was compared with the final diagnosis based on the pathological examination of specimens from surgery or EUS-guided fine-needle aspiration (EUS-FNA) or on follow-up for at least 12 months. The final diagnoses were: 18 adenocarcinomas, 9 neuroendocrine tumors, 7 chronic pancreatitis, and 1 stromal tumor. Power Doppler failed to display microcirculation, whereas harmonic imaging demonstrated it in all cases. Out of 18 lesions with a hypointense signal on CEH-EUS, 16 were adenocarcinomas. The sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), and accuracy of hypointensity for diagnosing pancreatic adenocarcinoma were 89 %, 88 %, 88 %, 89 %, and 88.5 %, compared with corresponding values of 72 %, 100 %, 77 %, 100 %, and 86 % for EUS-FNA. Of five adenocarcinomas with false-negative results at EUS-FNA, four had a hypointense echo signal at CEH-EUS. CEH-EUS with the new Olympus prototype device successfully visualizes the microvascular pattern in pancreatic solid lesions, and may be useful for distinguishing adenocarcinomas from other pancreatic masses.

  6. Medical Image Visual Appearance Improvement Using Bihistogram Bezier Curve Contrast Enhancement: Data from the Osteoarthritis Initiative

    Directory of Open Access Journals (Sweden)

    Hong-Seng Gan

    2014-01-01

    Full Text Available Well-defined image can assist user to identify region of interest during segmentation. However, complex medical image is usually characterized by poor tissue contrast and low background luminance. The contrast improvement can lift image visual quality, but the fundamental contrast enhancement methods often overlook the sudden jump problem. In this work, the proposed bihistogram Bezier curve contrast enhancement introduces the concept of “adequate contrast enhancement” to overcome sudden jump problem in knee magnetic resonance image. Since every image produces its own intensity distribution, the adequate contrast enhancement checks on the image’s maximum intensity distortion and uses intensity discrepancy reduction to generate Bezier transform curve. The proposed method improves tissue contrast and preserves pertinent knee features without compromising natural image appearance. Besides, statistical results from Fisher’s Least Significant Difference test and the Duncan test have consistently indicated that the proposed method outperforms fundamental contrast enhancement methods to exalt image visual quality. As the study is limited to relatively small image database, future works will include a larger dataset with osteoarthritic images to assess the clinical effectiveness of the proposed method to facilitate the image inspection.

  7. A new automated quantification algorithm for the detection and evaluation of focal liver lesions with contrast-enhanced ultrasound.

    Science.gov (United States)

    Gatos, Ilias; Tsantis, Stavros; Spiliopoulos, Stavros; Skouroliakou, Aikaterini; Theotokas, Ioannis; Zoumpoulis, Pavlos; Hazle, John D; Kagadis, George C

    2015-07-01

    Detect and classify focal liver lesions (FLLs) from contrast-enhanced ultrasound (CEUS) imaging by means of an automated quantification algorithm. The proposed algorithm employs a sophisticated segmentation method to detect and contour focal lesions from 52 CEUS video sequences (30 benign and 22 malignant). Lesion detection involves wavelet transform zero crossings utilization as an initialization step to the Markov random field model toward the lesion contour extraction. After FLL detection across frames, time intensity curve (TIC) is computed which provides the contrast agents' behavior at all vascular phases with respect to adjacent parenchyma for each patient. From each TIC, eight features were automatically calculated and employed into the support vector machines (SVMs) classification algorithm in the design of the image analysis model. With regard to FLLs detection accuracy, all lesions detected had an average overlap value of 0.89 ± 0.16 with manual segmentations for all CEUS frame-subsets included in the study. Highest classification accuracy from the SVM model was 90.3%, misdiagnosing three benign and two malignant FLLs with sensitivity and specificity values of 93.1% and 86.9%, respectively. The proposed quantification system that employs FLLs detection and classification algorithms may be of value to physicians as a second opinion tool for avoiding unnecessary invasive procedures.

  8. Clinical Applications of Contrast-Enhanced Ultrasound in the Pediatric Work-Up of Focal Liver Lesions and Blunt Abdominal Trauma

    DEFF Research Database (Denmark)

    Laugesen, Nicolaj Grønbæk; Nolsoe, Christian Pallson; Rosenberg, Jacob

    2017-01-01

    of CEUS is indeed promising. However, no ultrasound contrast agent manufactured today is registered for pediatric use in Europe. The contrast agent SonoVue(®) has recently been approved by the FDA under the name of Lumason(®) to be used in hepatic investigations in adults and children. This article...... help reduce radiation exposure and use of iodinated contrast agents in pediatrics, thereby potentially reducing complications in routine imaging.......In pediatrics ultrasound has long been viewed more favorably than imaging that exposes patients to radiation and iodinated contrast or requires sedation. It is child-friendly and diagnostic capabilities have been improved with the advent of contrast-enhanced ultrasound (CEUS). The application...

  9. Correlation of contrast-enhanced ultrasound parameters with oncogene expression and cell proliferation activity in breast cancer

    Institute of Scientific and Technical Information of China (English)

    Ce Zhang

    2017-01-01

    Objective: To study the correlation of contrast-enhanced ultrasound parameters with oncogene expression and cell proliferation activity in breast cancer. Methods: Breast cancer lesions and benign breast lesions surgically removed in Zigong Third People's Hospital between May 2014 and February 2017 were selected, contrast-enhanced ultrasound was done before operation to draw the time-intensity curve and calculate the area under the curve (AUC), and the expression of proliferation molecules and tumor suppressor genes were detected after operation. Results:The contrast-enhanced ultrasound parameter AUC of the breast cancer lesion was greatly higher than that of the benign breast lesion; ECT2, ZKSCAN3, USP39 and EphA2 mRNA expression in breast cancer lesions were obviously higher than those in benign breast lesions whereas HPK1, TCEAL17, CCN5, ATG2B and ATG4D mRNA expression were greatly lower than those in benign breast lesions; ECT2, ZKSCAN3, USP39 and EphA2 mRNA expression in breast cancer lesions with high AUC were greatly higher than those in breast cancer lesions with low AUC whereas HPK1, TCEAL17, CCN5, ATG2B and ATG4D mRNA expression were greatly lower than those in breast cancer lesions with low AUC. Conclusion: The contrast-enhanced ultrasound parameter AUC of breast cancer lesion significantly increases and is closely related to the higher expression of pro-proliferation molecules and the lower expression of tumor suppressor genes.

  10. Contrast-enhanced ultrasound and computed tomography findings of granulomatosis with polyangiitis presenting with multiple intrarenal microaneurysms: A case report.

    Science.gov (United States)

    Kim, Youe Ree; Lee, Young Hwan; Lee, Jong-Ho; Yoon, Kwon-Ha

    Granulomatosis with polyangiitis (GPA) is a systemic disorder that affects small- and medium- sized vessels in many organs. Although the kidneys are the second most commonly involved organ in patients with GPA, its manifestation as multiple intrarenal aneurysms is rare. We report an unusual manifestation of GPA with multiple intrarenal microaneurysms, as demonstrated by contrast-enhanced ultrasound and computed tomography. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Avascular necrosis of femoral head: findings of contrast-enhanced MR imaging

    International Nuclear Information System (INIS)

    Shin, Yong Moon; Kang, Heung Sik; Kim, Chu Wan; Kim, Hee Joong; Kim, Young Min

    1995-01-01

    To evaluate the findings and the role of contrast enhanced magnetic resonance imaging in avascular necrosis of femoral head. Sixteen patients with avascular necorsis of femoral head were examined with MRI. T1-weighted and T2-weighted image and contrast-enhanced T1-weighted images were obtained. Enhancing characteristics of the necrotic area and synovium were determined. Also a change of the disease extent after enhancement was assessed. Twenty seven avascular necrosis of the femoral head including 11 cases of bilateral lesion were detected. Fifteen cases revealed collapse of the femoral head. The portions of the lesion with low signal intensity on T1-weighted images and high signal intensity on T2-weighted images showed contrast enhancement in 15 cases. However, the potions with low signal intensities both on T1 and T2-weighted images showed enhancement in one case. There was no significant change of the disease extent after enhancement. Synovium showed enhancement in 18 cases, and joint effusion was detected in 23 cases. Contrast enhanced MR images may be helpful in predicting histopathologic findings of avascular necrosis of the femoral head, but not useful for evaluating the extent of disease

  12. Avascular necrosis of femoral head: findings of contrast-enhanced MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Yong Moon; Kang, Heung Sik; Kim, Chu Wan; Kim, Hee Joong; Kim, Young Min [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1995-06-15

    To evaluate the findings and the role of contrast enhanced magnetic resonance imaging in avascular necrosis of femoral head. Sixteen patients with avascular necorsis of femoral head were examined with MRI. T1-weighted and T2-weighted image and contrast-enhanced T1-weighted images were obtained. Enhancing characteristics of the necrotic area and synovium were determined. Also a change of the disease extent after enhancement was assessed. Twenty seven avascular necrosis of the femoral head including 11 cases of bilateral lesion were detected. Fifteen cases revealed collapse of the femoral head. The portions of the lesion with low signal intensity on T1-weighted images and high signal intensity on T2-weighted images showed contrast enhancement in 15 cases. However, the potions with low signal intensities both on T1 and T2-weighted images showed enhancement in one case. There was no significant change of the disease extent after enhancement. Synovium showed enhancement in 18 cases, and joint effusion was detected in 23 cases. Contrast enhanced MR images may be helpful in predicting histopathologic findings of avascular necrosis of the femoral head, but not useful for evaluating the extent of disease.

  13. Contrast-enhanced ultrasound for quantitative assessment of portal pressure in canine liver fibrosis.

    Science.gov (United States)

    Zhai, Lin; Qiu, Lan-Yan; Zu, Yuan; Yan, Yan; Ren, Xiao-Zhuan; Zhao, Jun-Feng; Liu, Yu-Jiang; Liu, Ji-Bin; Qian, Lin-Xue

    2015-04-21

    To explore the feasibility of non-invasive quantitative estimation of portal venous pressure by contrast-enhanced ultrasound (CEUS) in a canine model. Liver fibrosis was established in adult canines (Beagles; n = 14) by subcutaneous injection of carbon tetrachloride (CCl4). CEUS parameters, including the area under the time-intensity curve and intensity at portal/arterial phases (Qp/Qa and Ip/Ia, respectively), were used to quantitatively assess the blood flow ratio of the portal vein/hepatic artery at multiple time points. The free portal venous pressures (FPP) were measured by a multi-channel baroreceptor using a percutaneous approach at baseline and 8, 16, and 24 wk after CCl4 injections in each canine. Liver biopsies were obtained at the end of 8, 16, and 24 wk from each animal, and the stage of the fibrosis was assessed according to the Metavir scoring system. A Pearson correlation test was performed to compare the FPP with Qp/Qa and Ip/Ia. Pathologic examination of 42 biopsies from the 14 canines at weeks 8, 16, and 24 revealed that liver fibrosis was induced by CCl4 and represented various stages of liver fibrosis, including F0 (n = 3), F1 (n = 12), F2 (n = 14), F3 (n = 11), and F4 (n = 2). There were significant differences in the measurements of Qp/Qa (19.85 ± 3.30 vs 10.43 ± 1.21, 9.63 ± 1.03, and 8.77 ± 0.96) and Ip/Ia (1.77 ± 0.37 vs 1.03 ± 0.12, 0.83 ± 0.10, and 0.69 ± 0.13) between control and canine fibrosis at 8, 16, and 24 wk, respectively (all P fibrosis model. Prediction of elevated FPP based on Qp/Qa and Ip/Ia was highly sensitive, as assessed by the area under the receiver operating curve (0.866 and 0.895, respectively). CEUS is a potential method to accurately, but non-invasively, estimate portal venous pressure through measurement of Qp/Qa and Ip/Ia parameters.

  14. Imaging of the acute scrotum: is there a place for contrast-enhanced ultrasonography?

    Directory of Open Access Journals (Sweden)

    H. Moschouris

    2009-12-01

    Full Text Available Purpose: To present and evaluate the findings of contrast-enhanced ultrasonography (CEUS in typical cases of acute painful scrotum. Materials and methods: Nineteen patients aged from 19 to 61 years old were included in the study. All patients underwent grey-scale and color Doppler ultrasonography (US of the scrotum, followed by imaging after i.v. administration of 2.4 mL of a second generation ultrasound contrast agent (microbubbles of sulphur hexafluoride. A dedicated, contrast-sensitive technique was used (Contrast Tissue Imaging - CnTI. The diagnosis was confirmed surgically in 6 cases while in the remaining 8 cases it was based on the combination of clinical, imaging and laboratory findings. Results: The final diagnosis was testicular torsion (n = 4, epididymitis (n = 2, one of the cases complicated by abscess, testicular abscess (n = 1, scrotal abscess (n = 1, testicular trauma of varying severity (n = 6. Five out of 19 cases were true negatives: neither clinical examination nor laboratory tests revealed any pathology. CEUS showed complete lack of enhancement in all cases of torsion, permitting a rapid and definitive diagnosis. In the cases of infection complicated by abscesses, CEUS delineated the lesions much better than the combination of B-mode/Color Doppler US. The severely traumatized testicles showed minimal, inhomogeneous or patchy enhancement, while cases of minor trauma showed no significant enhancement defects. Hematomas were presented as non-enhancing lesions. Conclusion: Generally, there was no advantage over Doppler US as has been previously shown. However, CEUS can be used supplementary to traditional Doppler US in the investigation of blunt testicular trauma especially when there is uncertainty in diagnosis after appropriate clinical and radiographic evaluations occurs. Further studies are required to clearly define the indications of this method.

  15. Radiofrequency ablation of renal tumours: diagnostic accuracy of contrast-enhanced ultrasound for early detection of residual tumour

    International Nuclear Information System (INIS)

    Hoeffel, Christine; Pousset, Maud; Elie, Caroline; Timsit, Marc-Olivier; Mejean, Arnaud; Merran, Samuel; Tranquart, Francois; Khairoune, Ahmed; Helenon, Olivier; Correas, Jean-Michel; Joly, Dominique; Richard, Stephane

    2010-01-01

    To evaluate the diagnostic accuracy of contrast-enhanced ultrasound (CEUS) in the early detection of residual tumour after radiofrequency ablation (RFA) of renal tumours. Patients referred to our institution for RFA of renal tumours prospectively underwent CEUS and computed tomography (CT) or magnetic resonance imaging (MRI) before, within 1 day and 6 weeks after treatment. Identification of residual tumour was assessed by three blinded radiologists. Reference standard was CT/MRI performed at least 1 year after RFA. A total of 66 renal tumours in 43 patients (median age 62 years; range 44-71.5) were studied. Inter-reader agreement (κ value) was 0.84 for CEUS. Prevalence of residual disease was 19%. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV), respectively, were as follows: 64% [confidence interval (CI) 39-84], 98% [CI 91-100], 82% [CI 52-95] and 92% [CI 83-97] on 24-h CEUS; 79% [CI 52-92], 100% [CI 94-100], 100% [CI 74-100] and 95% [CI 87-100] on 6-week CEUS; 79% [CI 52-92], 95% [CI 86-98], 79% [CI 52-92] and 95% [CI 86-98] on 24-h CT/MRI; and 100% [CI 72-100], 98% [CI 90-100], 91% [CI 62-98] and 100% [CI 93-100] on 6-week CT/MRI. CEUS has high specificity for the early diagnosis of residual tumour after renal RFA. (orig.)

  16. Improvement of Fuzzy Image Contrast Enhancement Using Simulated Ergodic Fuzzy Markov Chains

    Directory of Open Access Journals (Sweden)

    Behrouz Fathi-Vajargah

    2014-01-01

    Full Text Available This paper presents a novel fuzzy enhancement technique using simulated ergodic fuzzy Markov chains for low contrast brain magnetic resonance imaging (MRI. The fuzzy image contrast enhancement is proposed by weighted fuzzy expected value. The membership values are then modified to enhance the image using ergodic fuzzy Markov chains. The qualitative performance of the proposed method is compared to another method in which ergodic fuzzy Markov chains are not considered. The proposed method produces better quality image.

  17. [Value of contrast-enhanced ultrasound (CEUS) in the differential diagnosis between benign and malignant renal neoplasms].

    Science.gov (United States)

    Zhang, Sheng; Wang, Xiao-qing; Xin, Xiao-jie; Xu, Yong

    2013-05-01

    To investigate the value of contrast enhanced ultrasound (CEUS) imaging in the differential diagnosis between benign and malignant renal neoplasms. Two hundred and forty-five cases of renal space-occupying lesions confirmed by biopsy or surgical pathology were included in this study. The CEUS features of the renal space-occupying lesions, i.e., the enhancement degree, homogeneity of enhancement, washing-in and washing-out time and enhancement pattern, were retrospectively analyzed. There were 210 cases of malignant renal tumors and 35 cases of benign lesions. The CEUS modes of the malignant renal tumors included "quick in and quick out" 82 cases, "quick in and slow out" 64 cases, "slow in and quick out" 18 cases and "slow in and slow out" 46 cases; good enhancement 150 cases (71.4%) and inhomogeneous enhancement 180 cases (85.7%).Both the contrast agent filling defect area and solid component enhancement of solid-cystic tumors were important features of malignant renal tumors. In the 35 cases of benign lesions,the CEUS modes included "quick in and quick out" 4 cases, "quick in and slow out" 8 cases, "slow in and quick out" 10 cases and "slow in and slow out" 13 cases. Most of the benign tumors showed low enhancement 51.4% (18/35) and inhomogeneous enhancement 54.3% (19/35). There were significant differences between the malignant and benign renal neoplasms in CEUS mode, degree of enhancement and homogeneity of enhancement (P benign and malignant tumors were 77.1% and 83.8%, respectively, while the two-dimensional ultrasound diagnosis of benign and malignant tumors were 68.6% and 76.7%, respectively, with a significant difference (P benign and malignant renal lesions.

  18. Diagnostic accuracy of contrast-enhanced ultrasound in differentiating benign and malignant focal liver lesions: a retrospective study

    International Nuclear Information System (INIS)

    Ooi, Chin-Chin; Low, Su-Chong Albert; Lim, Sze-Ying; Bakar, Rafidah Abu; Lo, Richard Hoau-Gong; Schneider-Kolsky, Michal; Lombardo, Paul

    2010-01-01

    Full text: Purpose: The purpose of this study was to access the diagnostic accuracy of our early experience with contrast-enhanced ultrasound (CEUS) in the characterisation of focal liver lesions (FLLs) using histopathology, contrastenhanced computed tomography (CT), magnetic resonance imaging (MRI) or other imaging follow-up as the standard of reference. Materials and Methods: Seventy-three patients with 82 FLLs who underwent liver CEUS from January 2006 to December 2008 were retrospectively reviewed. CEUS was performed with up to 4.8 mL of SonoVue (Bracco, Milan, Italy) using a low mechanical index mode. The CEUS findings were compared with histopathology, or where histopathology was not available, clinical and imaging follow-up over at least 12 months was used as the standard of reference. Results: Of the 82 FLLs, 50 were malignant and 32 were benign at final diagnosis. CEUS correctly identified 43 malignant FLLs, with final diagnosis confirmed by histopathology in 13 lesions and clinico-radiological follow-up in 30 lesions. Twenty-nine lesions were correctly identified as benign on CEUS, with all these lesions confirmed on c1inico-radiological follow-up. CEUS demonstrated a sensitivity of 86.0% and a specificity of 90.6% in the characterisation of liver lesions as malignant, with an overall accuracy of 87.8% (P< 0.05). Conclusion: Our early experience has shown that CEUS can be accurate in differentiating malignant from benign FLLs and may become a useful first-line imaging tool where CT or MRI are not available or contra-indicated.

  19. Independent component analysis of dynamic contrast-enhanced computed tomography images

    Energy Technology Data Exchange (ETDEWEB)

    Koh, T S [School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Ave, Singapore 639798 (Singapore); Yang, X [School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Ave, Singapore 639798 (Singapore); Bisdas, S [Department of Diagnostic and Interventional Radiology, Johann Wolfgang Goethe University Hospital, Theodor-Stern-Kai 7, D-60590 Frankfurt (Germany); Lim, C C T [Department of Neuroradiology, National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore 308433 (Singapore)

    2006-10-07

    Independent component analysis (ICA) was applied on dynamic contrast-enhanced computed tomography images of cerebral tumours to extract spatial component maps of the underlying vascular structures, which correspond to different haemodynamic phases as depicted by the passage of the contrast medium. The locations of arteries, veins and tumours can be separately identified on these spatial component maps. As the contrast enhancement behaviour of the cerebral tumour differs from the normal tissues, ICA yields a tumour component map that reveals the location and extent of the tumour. Tumour outlines can be generated using the tumour component maps, with relatively simple segmentation methods. (note)

  20. Diagnostic Performance and Confidence of Contrast-Enhanced Ultrasound in the Differential Diagnosis of Cystic and Cysticlike Liver Lesions.

    Science.gov (United States)

    Corvino, Antonio; Catalano, Orlando; Corvino, Fabio; Sandomenico, Fabio; Petrillo, Antonella

    2017-09-01

    The aims of this study were to assess the diagnostic performance of contrast-enhanced ultrasound (CEUS) in the characterization of atypical cystic and cysticlike focal liver lesions in comparison with conventional US and to determine whether the use of CEUS can reduce the need for further diagnostic workup. In a 3-year period 48 patients with 50 atypical cystic and cysticlike lesions found at conventional US underwent CEUS. Diagnostic confirmation was obtained in cytohistopathologic examinations, with other imaging modalities, and in follow-up. Overall, there were 24 cystic lesions and 26 cysticlike solid lesions, specifically 32 benign and 18 malignant lesions. The conventional US and CEUS images and cine loops were reviewed by two blinded readers independently. Sensitivity, specificity, area under the ROC curve (A z ), and interobserver agreement were calculated. Diagnostic performance improved after review of CEUS examinations by both readers (conventional US A z = 0.781 vs 0.972; CEUS A z = 0.734 vs 0.957). Interreader agreement increased, although slightly (conventional US weighted κ = 0.894; CEUS weighted κ = 0.953). In terms of differential diagnosis, the occurrence of correctly characterized lesions increased after CEUS for both readers (reader 1, 62% to 98%; reader 2, 56% to 96%). The development of low-acoustic-power CEUS has made it possible to identify several imaging features of cystic and cysticlike focal liver lesions that, in association with history and clinical findings, may help to correctly characterize them. Our data indicate the usefulness of CEUS in the evaluation of patients with these lesions.

  1. Digital contrast enhancement of 18Fluorine-fluorodeoxyglucose positron emission tomography images in hepatocellular carcinoma

    International Nuclear Information System (INIS)

    Pandey, Anil Kumar; Sharma, Sanjay Kumar; Agarwal, Krishan Kant; Sharma, Punit; Bal, Chandrasekhar; Kumar, Rakesh

    2016-01-01

    The role of 18 fluorodeoxyglucose positron emission tomography (PET) is limited for detection of primary hepatocellular carcinoma (HCC) due to low contrast to the tumor, and normal hepatocytes (background). The aim of the present study was to improve the contrast between the tumor and background by standardizing the input parameters of a digital contrast enhancement technique. A transverse slice of PET image was adjusted for the best possible contrast, and saved in JPEG 2000 format. We processed this image with a contrast enhancement technique using 847 possible combinations of input parameters (threshold “m” and slope “e”). The input parameters which resulted in an image having a high value of 2 nd order entropy, and edge content, and low value of absolute mean brightness error, and saturation evaluation metrics, were considered as standardized input parameters. The same process was repeated for total nine PET-computed tomography studies, thus analyzing 7623 images. The selected digital contrast enhancement technique increased the contrast between the HCC tumor and background. In seven out of nine images, the standardized input parameters “m” had values between 150 and 160, and for other two images values were 138 and 175, respectively. The value of slope “e” was 4 in 4 images, 3 in 3 images and 1 in 2 images. It was found that it is important to optimize the input parameters for the best possible contrast for each image; a particular value was not sufficient for all the HCC images. The use of above digital contrast enhancement technique improves the tumor to background ratio in PET images of HCC and appears to be useful. Further clinical validation of this finding is warranted

  2. Feature and Contrast Enhancement of Mammographic Image Based on Multiscale Analysis and Morphology

    Directory of Open Access Journals (Sweden)

    Shibin Wu

    2013-01-01

    Full Text Available A new algorithm for feature and contrast enhancement of mammographic images is proposed in this paper. The approach bases on multiscale transform and mathematical morphology. First of all, the Laplacian Gaussian pyramid operator is applied to transform the mammography into different scale subband images. In addition, the detail or high frequency subimages are equalized by contrast limited adaptive histogram equalization (CLAHE and low-pass subimages are processed by mathematical morphology. Finally, the enhanced image of feature and contrast is reconstructed from the Laplacian Gaussian pyramid coefficients modified at one or more levels by contrast limited adaptive histogram equalization and mathematical morphology, respectively. The enhanced image is processed by global nonlinear operator. The experimental results show that the presented algorithm is effective for feature and contrast enhancement of mammogram. The performance evaluation of the proposed algorithm is measured by contrast evaluation criterion for image, signal-noise-ratio (SNR, and contrast improvement index (CII.

  3. Use of Contrast-Enhanced Ultrasound to Study Relationship between Serum Uric Acid and Renal Microvascular Perfusion in Diabetic Kidney Disease

    Directory of Open Access Journals (Sweden)

    Ling Wang

    2015-01-01

    Full Text Available Purpose. To investigate the relationship between uric acid and renal microvascular perfusion in diabetic kidney disease (DKD using contrast-enhanced ultrasound (CEUS method. Materials and Methods. 79 DKD patients and 26 healthy volunteers were enrolled. Renal function and urine protein markers were tested. DKD patients were subdivided into two groups including a normal serum uric acid (SUA group and a high SUA group. Contrast-enhanced ultrasound (CEUS was performed, and low acoustic power contrast-specific imaging was used for quantitative analysis. Results. Normal controls (NCs had the highest levels of AUC, AUC1, and AUC2. Compared to the normal SUA DKD group, high SUA DKD patients had significantly higher IMAX, AUC, and AUC1 (P<0.05. DKD patients with low urinary uric acid (UUA excretion had significantly higher AUC2 compared to DKD patients with normal UUA (P<0.05. Conclusion. Hyperuricemia in DKD patients was associated with a renal ultrasound image suggestive of microvascular hyperperfusion. The CEUS parameter AUC1 holds promise as an indicator for renal microvascular hyperperfusion, while AUC2 might be a useful indicator of declining glomerular filtration rate in DKD patients with decreased excretion of uric acid.

  4. Imaging vascular function for early stage clinical trials using dynamic contrast-enhanced magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Leach, M.O.; Orton, M. [Institute of Cancer Research and Royal Marsden NHS Foundation Trust, Cancer Research UK and EPSRC Cancer Imaging Centre, Sutton, Surrey (United Kingdom); Morgan, B. [Univ. of Leicester, College of Medicine, Biological Sciences and Psychology, Leicester (United Kingdom); Tofts, P.S. [Brighton and Sussex Medical School, Univ. of Sussex, Clinical Imaging Sciences Centre, Sussex (United Kingdom); Buckley, D.L. [University of Leeds, Division of Medical Physics, Leeds (United Kingdom); Huang, W. [Oregon Health and Science Univ., Advanced Imaging Research Centre, Portland, OR (United States); Horsfield, M.A. [Medical Physics Section, Leicester Royal Infirmary, Dept. of Cardiovascular Sciences, Leicester (United Kingdom); Chenevert, T.L. [Univ. of Michigan Health System, Ann Arbor, MI (United States); Collins, D.J. [Royal Marsden Hospital NHS Foundation Trust, Cancer Research UK and EPSRC Cancer Imaging Centre, Sutton, Surrey (United Kingdom); Jackson, A. [Univ. of Manchester, Wolfson Molecular Imaging Centre, Withington, Manchester, M20 3LJ (United Kingdom); Lomas, D. [Univ. of Cambridge, Dept. of Radiology, Cambridge (United Kingdom); Whitcher, B. [Unit 2 Greenways Business Park, Mango Solutions, Chippenham (United Kingdom); Clarke, L. [Cancer Imaging Program, Imaging Technology Development Branch, Rockville, MD (United States); Plummer, R. [Univ. of Newcastle Upon Tyne, The Medical School, Medical Oncology, Northern Inst. for Cancer Research, Newcastle Upon Tyne (United Kingdom); Judson, I. [Royal Marsden Hospital, Sutton, Surrey (United Kingdom); Jones, R. [Beatson West of Scotland Cancer Centre, Glasgow (United Kingdom); Alonzi, R. [Mount Vernon Cancer Centre, Northwood (United Kingdom); Brunner, T. [Gray Inst. for Radiation, Oncology and Biology, Oxford (United Kingdom); Koh, D.M. [Royal Marsden NHS Foundation Trust, Diagnostic Radiology, Sutton, Surrey (United Kingdom)] [and others

    2012-07-15

    Many therapeutic approaches to cancer affect the tumour vasculature, either indirectly or as a direct target. Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) has become an important means of investigating this action, both pre-clinically and in early stage clinical trials. For such trials, it is essential that the measurement process (i.e. image acquisition and analysis) can be performed effectively and with consistency among contributing centres. As the technique continues to develop in order to provide potential improvements in sensitivity and physiological relevance, there is considerable scope for between-centre variation in techniques. A workshop was convened by the Imaging Committee of the Experimental Cancer Medicine Centres (ECMC) to review the current status of DCE-MRI and to provide recommendations on how the technique can best be used for early stage trials. This review and the consequent recommendations are summarised here. (orig.)

  5. Effect of contrast-enhanced ultrasound on differential diagnosis of intrahepatic cholangiocarcinoma and arterial phase enhanced hepatic inflammatory lesions

    Institute of Scientific and Technical Information of China (English)

    Shanshan Yin; Qiuli Cui; Kun Yan; Wei Yang; Wei Wu; Liping Bao; Minhua Chen

    2017-01-01

    Objective:To investigate differential diagnosis between intrahepatic cholangiocarcinoma (ICC) and arterial phase enhanced hepatic inflammatory lesions in patients without liver cirrhosis using contrast-enhanced ultrasound (CEUS).Methods:ICC and hepatic inflammatory lesions cases with CEUS and pathological diagnosis between Sep 2013 and Oct 2016 were investigated retrospectively.Imaging features of conventional ultrasound and CEUS were analyzed.The parameters of time intensity curve (TIC),including the arrival time,peak intensity (PI) in the lesions,the starting time for washout,and the intensity difference at 3 min (△I3) after contrast agent infection between the lesion and the liver parenchyma,were compared between ICC and hepatic inflammatory lesions.Results:Twenty-five ICC and fifteen inflammatory patients were included in this study.Seventeen ICC (68.0%) and two inflammatory cases (13.3%) showed bile duct dilatation on conventional ultrasound.Using CEUS,three ICC cases (12.0%) were misdiagnosed as inflammatory lesions and three inflammatory lesions (20.0%) as ICC;two ICC (8.0%) and one inflammatory case (6.7%) could not be made definite diagnosis.Washout started at 34.5±3.5 s and 61.5± 12.9 s for ICC and inflammatory lesions respectively (P<0.001).The intensity difference between lesion and liver parenchyma at 3 min after contrast agent injection was 10.8±3.1 dB in ICC and 4.2±2.3 dB in inflammatory group (P<0.00 1).The sensitivity and specificity differentiating ICC and inflammatory lesions were 76% and 87% if the cut-offvalue of the intensity difference was 7.7 dB.Conclusions:Combined with TIC analysis,and particularly with the characteristic of the early-starting and obvious washout in ICC,CEUS can be useful in differential diagnosis between hepatic inflammatory lesions and ICC.

  6. A review on brightness preserving contrast enhancement methods for digital image

    Science.gov (United States)

    Rahman, Md Arifur; Liu, Shilong; Li, Ruowei; Wu, Hongkun; Liu, San Chi; Jahan, Mahmuda Rawnak; Kwok, Ngaiming

    2018-04-01

    Image enhancement is an imperative step for many vision based applications. For image contrast enhancement, popular methods adopt the principle of spreading the captured intensities throughout the allowed dynamic range according to predefined distributions. However, these algorithms take little or no consideration into account of maintaining the mean brightness of the original scene, which is of paramount importance to carry the true scene illumination characteristics to the viewer. Though there have been significant amount of reviews on contrast enhancement methods published, updated review on overall brightness preserving image enhancement methods is still scarce. In this paper, a detailed survey is performed on those particular methods that specifically aims to maintain the overall scene illumination characteristics while enhancing the digital image.

  7. The role of contrast-enhanced ultrasound (CEUS) in visualizing atherosclerotic carotid plaque vulnerability: Which injection protocol? Which scanning technique?

    Energy Technology Data Exchange (ETDEWEB)

    Iezzi, Roberto, E-mail: roberto.iezzi@rm.unicatt.it [Department of Bioimaging and Radiological Sciences, Institute of Radiology, “A. Gemelli” Hospital—Catholic University, L.go A Gemelli 8, 00168 Rome (Italy); Petrone, Gianluigi [Institute of Pathology, “A. Gemelli” Hospital—Catholic University, L.go A Gemelli 8, 00168, Rome (Italy); Ferrante, Angela [Department of Vascular Surgery, “A. Gemelli” Hospital—Catholic University, L.go A Gemelli 8, 00168 Rome (Italy); Lauriola, Libero [Institute of Pathology, “A. Gemelli” Hospital—Catholic University, L.go A Gemelli 8, 00168, Rome (Italy); Vincenzoni, Claudio [Department of Vascular Surgery, “A. Gemelli” Hospital—Catholic University, L.go A Gemelli 8, 00168 Rome (Italy); Torre, Michele Fabio la [Department of Bioimaging and Radiological Sciences, Institute of Radiology, “A. Gemelli” Hospital—Catholic University, L.go A Gemelli 8, 00168 Rome (Italy); Snider, Francesco [Department of Vascular Surgery, “A. Gemelli” Hospital—Catholic University, L.go A Gemelli 8, 00168 Rome (Italy); Rindi, Guido [Institute of Pathology, “A. Gemelli” Hospital—Catholic University, L.go A Gemelli 8, 00168, Rome (Italy); Bonomo, Lorenzo [Department of Bioimaging and Radiological Sciences, Institute of Radiology, “A. Gemelli” Hospital—Catholic University, L.go A Gemelli 8, 00168 Rome (Italy)

    2015-05-15

    Highlights: • CEUS is a safe and efficacious technique for the identification and characterization of carotid plaque. • CEUS represents a diagnostic tool for the management of patients with carotid plaque, particularly in asymptomatic patients. • Improved diagnostic performance is achieved with the injection of 4 mL bolus of contrast-medium. • Improved diagnostic performance is achieved with the use of Dynamic Imaging rather than late-phase imaging. - Abstract: Purpose: To correlate the degree of plaque vulnerability as determined by contrast-enhanced ultrasound (CEUS) with histological findings. Secondary objectives were to optimize the CEUS acquisition technique and image evaluation methods. Materials and methods: Fifty consecutive patients, either symptomatic and asymptomatic referring to our department in order to perform carotid endarterectomy (TEA), were enrolled. Each patient provided informed consent before undergoing CEUS. Ultrasound examination was performed using high-frequency (8–14 MHz) linear probe and a non-linear pulse inversion technique (mechanical index: 0.09–1.3). A double contrast media injection (Sonovue, 2 mL and 4 mL; Bracco, Italy) was performed. Two videotapes were recorded for every injection: early “dynamic” phase and late “flash” phase, performed with 6 high mechanical index impulses. Movies were quantitatively and qualitatively evaluated. Qualitative and quantitative evaluation were statistically compared to immunohistological diagnosis of vulnerable plaque, considered as gold standard. Results: Qualitative CEUS evaluation obtained high statistical results when compared to immunohistological results, with values of sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy of 94%, 68%, 87%, 85% and 86%, respectively, which became higher if considering only asymptomatic patient, with a NPV of 91%. Nevertheless, quantitative software evaluation proved less

  8. Diagnostic Accuracy of Ultrasound, Contrast-enhanced CT, and Conventional MRI for Differentiating Leiomyoma From Leiomyosarcoma.

    Science.gov (United States)

    Gaetke-Udager, Kara; McLean, Karen; Sciallis, Andrew P; Alves, Timothy; Maturen, Katherine E; Mervak, Benjamin M; Moore, Andreea G; Wasnik, Ashish P; Erba, Jake; Davenport, Matthew S

    2016-10-01

    This study aimed to determine whether uterine leiomyoma can be distinguished from uterine leiomyosarcoma on ultrasound (US), computed tomography (CT), and/or magnetic resonance imaging (MRI) without diffusion-weighted imaging. Institutional review board approval was obtained and informed consent was waived for this Health Insurance Portability and Accountability Act-compliant retrospective case-control diagnostic accuracy study. All subjects with resected uterine leiomyosarcoma diagnosed over a 17-year period (1998-2014) at a single institution for whom pre-resection US (n = 10), CT (n = 11), or MRI (n = 7) was available were matched by tumor size and imaging modality with 28 subjects with resected uterine leiomyoma. Six blinded radiologists (three attendings, three residents) assigned 5-point Likert scores for the following features: (1) margins, (2) necrosis, (3) hemorrhage, (4) vascularity, (5) calcifications, (6) heterogeneity, and (7) likelihood of malignancy (primary end point). Mean suspicion scores were calculated and receiver operating characteristic curves were generated. The ability of individual morphologic features to predict malignancy was assessed with logistic regression. Mean suspicion scores were 2.5 ± 1.2 (attendings) and 2.4 ± 1.3 (residents) for leiomyoma, and 2.7 ± 1.3 (attendings) and 2.7 ± 1.4 (residents) for leiomyosarcoma. The areas under the receiver operating characteristic curves (range: 0.330-0.685) were not significantly different from chance, either overall (P = .36-.88) or by any modality (P = .28-.96), for any reader. Reader experience had no effect on diagnostic accuracy. No morphologic parameter was significantly predictive of malignancy (P = .10-.97). Uterine leiomyoma cannot be differentiated accurately from leiomyosarcoma on US, CT, or MRI without diffusion-weighted imaging. Copyright © 2016 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

  9. Morphological image processing for quantitative shape analysis of biomedical structures: effective contrast enhancement

    International Nuclear Information System (INIS)

    Kimori, Yoshitaka

    2013-01-01

    A contrast enhancement approach utilizing a new type of mathematical morphology called rotational morphological processing is introduced. The method is quantitatively evaluated and then applied to some medical images. Image processing methods significantly contribute to visualization of images captured by biomedical modalities (such as mammography, X-ray computed tomography, magnetic resonance imaging, and light and electron microscopy). Quantitative interpretation of the deluge of complicated biomedical images, however, poses many research challenges, one of which is to enhance structural features that are scarcely perceptible to the human eye. This study introduces a contrast enhancement approach based on a new type of mathematical morphology called rotational morphological processing. The proposed method is applied to medical images for the enhancement of structural features. The effectiveness of the method is evaluated quantitatively by the contrast improvement ratio (CIR). The CIR of the proposed method is 12.1, versus 4.7 and 0.1 for two conventional contrast enhancement methods, clearly indicating the high contrasting capability of the method

  10. 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

  11. Technical aspects of contrast-enhanced magnetic resonance imaging of the breast: literature review

    International Nuclear Information System (INIS)

    Leopoldino, Denise de Deus; Gracio, Tatiana Schiller; D'Ippolito, Giuseppe; Bezerra, Alexandre Sergio de Araujo; Gracio, Tatiana Schiller

    2005-01-01

    With the advances in surface coil technology and the development of new imaging protocols in addition to the increase of the use of contrast agents, contrast enhanced magnetic resonance imaging (MRI) has emerged as a promising modality for detection, diagnosis and staging of breast cancer. Despite these advances, there are some unresolved issues, including no defined standard technique for contrast-enhanced breast MRI and no standard criteria of interpretation for the evaluation of such studies. In this article, we review the literature and discuss the general requirements and recommendations for contrast agent-enhanced breast MRI, including image interpretation criteria, MR equipment, dedicated radiofrequency coils, use of paramagnetic contrast agents, fat-suppression techniques, planes of acquisition, pulse sequence specifications and artifact sources. (author)

  12. Contrast-enhanced MR imaging of the endolymphatic sac in patients with sudden hearing loss

    International Nuclear Information System (INIS)

    Naganawa, Shinji; Koshikawa, Tokiko; Fukatsu, Hiroshi; Ishigaki, Takeo; Nakashima, Tsutomu; Ichinose, Nobuyasu

    2002-01-01

    Our objective was to evaluate the frequency of contrast enhancement of the endolymphatic sac in patients with sudden hearing loss. Forty consecutive patients with sudden sensorineural hearing loss (20 males and 20 females; age range 11-82 years), 40 age-matched control subjects, and 5 patients with Meniere's disease were examined using the same imaging protocol on a 1.5-T MR system. Pre- and post-contrast-enhanced T1-weighted 3D spoiled gradient-echo sequence (3D SPGR; TR/TE=23/10 ms, no. of excitations=1, flip angle=30 ) images were obtained using a voxel size of 0.6 x 0.7 x 0.8 mm 3 . Contrast enhancement in the area of the endolymphatic sac was assessed by two radiologists, and the frequency of contrast enhancement was compared between the three study groups. Enhancement of the ipsilateral endolymphatic sac was observed in 30 of the 40 patients with sudden hearing loss (75%). Twenty of these 30 patients also showed enhancement on the contralateral side, and 1 patient showed enhancement only on the contralateral side. Only 1 of the 5 patients with Meniere's disease showed enhancement. Nine of the 40 control subjects (22.5%) showed enhancement (bilateral enhancement in 5 subjects, unilateral in 4). The frequency of enhancement in patients with sudden hearing loss was significantly higher than that in control subjects (P<0.0001) or patients with Meniere's disease (P<0.05). The frequency of contrast enhancement of the endolymphatic sac is significantly increased in patients with sudden hearing loss, but further study is necessary to clarify the relationship between this finding and the pathophysiology of sudden hearing loss. (orig.)

  13. Dynamics of contrast enhancement in MR imaging and power Doppler ultrasonography of solid breast lesions

    International Nuclear Information System (INIS)

    Reinikainen, H.; Paeaekkoe, E.; Suramo, I.; Paeivaensalo, M.; Rissanen, T.

    2002-01-01

    Purpose: To evaluate the dynamics of contrast enhancement in solid breast lesions at contrast-enhanced MR imaging and power Doppler ultrasonography (US) and to compare the methods to histology and to each other. Material and Methods: Forty breast lesions were prospectively examined with dynamic MR and power Doppler US. Time-signal intensity curves of enhancement were obtained for both methods. The shape of the curve was analyzed to be benign, indeterminate or malignant. The curves were also analyzed quantitatively by calculating the slope of the curve and the area under the curve (both methods), relative enhancement (MR), and time to peak (US). The lesions were divided into malignant lesions, fibroadenomas, and other benign lesions. The results were compared to histology. Results: In the subjective analysis of the MR curve in differentiating between benign and malignant lesions the accuracy was 90%. The MR curve also enabled differentiation between fibroadenomas and malignancies. The accuracy of the US curve was 38%. Quantitatively, statistically significant differences were found using all the MR variables, except between malignancies and fibroadenomas. Using the US variables, no significant difference was found between the groups. Conclusion: The dynamics of contrast-enhanced MR were reliable in the differential diagnosis of solid breast lesions, but contrast-enhanced power Doppler US was of limited value

  14. General Ultrasound Imaging

    Medline Plus

    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 ...

  15. The contribution of contrast enhanced ultrasound for the characterization of benign liver lesions in clinical practice - a monocentric experience.

    Science.gov (United States)

    Martie, Alina; Bota, Simona; Sporea, Ioan; Sirli, Roxana; Popescu, Alina; Danila, Mirela

    2012-12-01

    Contrast-enhanced ultrasound (CEUS) uses second generation microbubble contrast agents and is considered to be a useful imaging method for focal liver lesions (FLLs) characterization. To observe if CEUS increases the diagnostic performance of benign FLLs as compared with standard ultrasonography examination (US). This is a single centre study developed during September 2009- December 2011 in the Department of Gastroenterology and Hepatology, in Timisoara. We evaluated 386 benign FLLs diagnosed by means of CEUS. Before performing CEUS, all FLLs were examined by US and Power Doppler techniques. At CEUS, the benign nature of a lesion was established by the absence of washout in the portal and late phase. The typical features observed using contrast, allowed their classification in a particular type of pathology, according to the 2008 EFSUMB Guidelines. From 386 benign FLLs, 81 (20.9%) of them were diagnosed in patients with chronic liver disease, while 305 (79.1%) were in patients without chronic hepatopathy. In 355 (92%) cases CEUS established a particular type of pathology. The most frequent lesions were: hemangiomas (37.5%), focal fatty alterations (24.8%), complex cysts (10.7%) and regenerative nodules (11.8%). Based on US we correctly estimated the positive diagnosis in 55.7% cases and using CEUS, the diagnostic performance increased up to 92%. In our study, by means of US the estimate positive diagnosis was made in 55.7% of cases. CEUS properly characterized 92% of benign FLLs and increased the diagnostic performance of these lesions, as compared with US.

  16. Detection of urinary leakage after radical retropubic prostatectomy by contrast enhanced ultrasound - do we still need conventional retrograde cystography?

    Science.gov (United States)

    Schoeppler, Gita M; Buchner, Alexander; Zaak, Dirk; Khoder, Wael; Staehler, Michael; Stief, Christian G; Reiser, Maximilian F; Clevert, Dirk-Andre

    2010-12-01

    To prospectively evaluate the accuracy of transvesical contrast-enhanced ultrasound (CEUS) as an alternative method for the detection of anastomotic leakage after radical retropubic prostatectomy (RRP) in comparison with the current standard method of conventional retrograde cystography (CG). Forty-three patients underwent RRP for histologically proven localized prostate cancer. The vesico-urethral anastomosis was evaluated 8 days after RRP by CG and CEUS. Any peri-anastomotic leakage was assessed and determined in CG and CEUS as follows: no extravasation (EV), small leakage (≤0.5 cm), moderate leakage (>0.5 cm to ≤2 cm), large leakage (>2 cm diameter of EV seen). In total, 21 (49%) patients showed a watertight anastomosis. Ten (23%), two (4.7%) and ten (23%) patients showed a small, intermediate and large EV, respectively. In 31 cases (72%) there was 100% agreement of CG and CEUS for detection of no, moderate and large EV, respectively. In nine cases a small and in two cases a moderate EV was categorized as watertight anastomosis by CEUS. Only in one case did CG detect a small EV where a large EV was detected in CEUS. The agreement between both methods was 95% for detecting absence or large leakages. CEUS is a promising imaging modality that seems to be equivalent to CG for detecting the presence of a large anastomotic leakage that is clinically relevant for postoperative persistence of the indwelling catheter. CEUS could be a cheap and time-saving alternative to the CG without exposure of the patient to radiation. © 2010 THE AUTHORS. JOURNAL COMPILATION © 2010 BJU INTERNATIONAL.

  17. 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.

  18. Magnetic resonance imaging of urinary bladder carcinoma: tumor staging and gadolinium contrast-enhanced imaging

    International Nuclear Information System (INIS)

    Doringer, E.; Joos, H.; Forstner, R.; Schmoller, H.

    1992-01-01

    Forty-nine patients with urinary bladder carcinomas underwent pre-operative examinations using magnetic resonance (MR) imaging. The results of the MR examinations were correlated with the clinical-pathological findings following transurethral resection (TUR) and bimanual palpation (n = 47) or radical cystectomy (n = 2). The results of pre-contrast MR tumor staging (T1, T2), viewing stages Tis-T2 collectively, and subsequent to separate assessments of stages T3b-T4b, were correct 76.6% of the time. Gadolinium-DTPA (Gd-DTPA) contrast-enhanced examinations (pre-contrast T1 and after Gd-DTPA) showed a staging accuracy rate of 85.7%. T2-weighted images did not indicate any advantage when compared to T1-weighted images following Gd-DTPA. The signal intensity ratios of tumor/fat and tumor/muscle tissue were measured on T1-weighted pre-contrast images and following Gd-DTPA and then evaluated statistically, whereby the increased tumor signal intensity was statistically significant (Wilcoxon test, P < 0.01). Due to the relatively short examination time needed for T1-weighted images and the specific tumor enhancement, the administration of Gd-DTPA proves valuable in the diagnosis of bladder carcinomas. T2-weighted images are not necessary. (orig.)

  19. Contrast-enhanced MR imaging of the breast in patients with breast implants after cancer surgery

    International Nuclear Information System (INIS)

    Bone, B.; Aspelin, P.; Isberg, B.; Perbeck, L.; Veress, B.

    1995-01-01

    The purpose of the study was to determine the value of contrast-enhanced MR imaging in the assessment of local recurrence in breast cancer patients who underwent mastectomy and breast reconstruction with an implant. Eighty-three patients have been evaluated by semidynamic contrast-enhanced MR imaging. The T1-weighted FLASH 3-D sequence was repeated twice postcontrast for evaluation of the entire breast bilaterally. The findings were compared to physical examination, mammography and histopathology. Recurrence verified by histopathology occurred in 14 of 83 patients (17%). Contrast-enhanced MR imaging was superior to palpation and mammography in revealing recurrences, especially when these were located close to the chest wall. MR was also more sensitive in detecting multiple foci of cancers. Our study revealed that MR imaging was influenced by size, type and composition of the tumor, as illustrated by the false-negative results. Therefore, the use of all 3 investigation methods is necessary for detecting recurrence at an early stage during the postoperative follow-up. (orig.)

  20. Multipeak Mean Based Optimized Histogram Modification Framework Using Swarm Intelligence for Image Contrast Enhancement

    Directory of Open Access Journals (Sweden)

    P. Babu

    2015-01-01

    Full Text Available A novel approach, Multipeak mean based optimized histogram modification framework (MMOHM is introduced for the purpose of enhancing the contrast as well as preserving essential details for any given gray scale and colour images. The basic idea of this technique is the calculation of multiple peaks (local maxima from the original histogram. The mean value of multiple peaks is computed and the input image’s histogram is segmented into two subhistograms based on this multipeak mean (mmean value. Then, a bicriteria optimization problem is formulated and the subhistograms are modified by selecting optimal contrast enhancement parameters. While formulating the enhancement parameters, particle swarm optimization is employed to find optimal values of them. Finally, the union of the modified subhistograms produces a contrast enhanced and details preserved output image. This mechanism enhances the contrast of the input image better than the existing contemporary HE methods. The performance of the proposed method is well supported by the contrast enhancement quantitative metrics such as discrete entropy, natural image quality evaluator, and absolute mean brightness error.

  1. Acetabular labral tears: contrast-enhanced MR imaging under continuous leg traction

    Energy Technology Data Exchange (ETDEWEB)

    Nishii, T. [Div. of Functional Diagnostic Imaging, Biomedical Research Center, Osaka Univ. Medical School, Suita (Japan); Nakanishi, K. [Dept. of Radiology, Osaka Univ. Medical School, Suita (Japan); Sugano, N. [Dept. of Orthopaedic Surgery, Osaka Univ. Medical School, Suita (Japan); Naito, H. [Div. of Functional Diagnostic Imaging, Biomedical Research Center, Osaka Univ. Medical School, Suita (Japan); Tamura, S. [Div. of Functional Diagnostic Imaging, Biomedical Research Center, Osaka Univ. Medical School, Suita (Japan); Ochi, T. [Dept. of Orthopaedic Surgery, Osaka Univ. Medical School, Suita (Japan)

    1996-05-01

    The objective of this study was to evaluate the effects of continuous leg traction on contrast-enhanced MR imaging of the hip joint and to determine whether MR imaging under these conditions is useful for demonstrating acetabular labral tears. Nineteen hips underwent MR imaging with a T1-weighted spin-echo sequence, followed by MR imaging under continuous leg traction after intravenous injection of gadolinium-DTPA. Joint fluid enhancement and labral contour detection were evaluated. Eleven hips had labral tears shown by conventional arthrography, arthroscopy and macroscopic surgical findings. Assessment of labral tears by MR imaging was correlated with the diagnosis based on these standard techniques. Joint fluid enhancement was obtained in all hips at 30 min after injection. Superior and inferior labral surfaces were completely delineated in 1 hip on the unenhanced MR images, and in 7 and 13 hips, respectively, on the enhanced images under traction. The enhanced images under traction depicted 9 of the 11 labral tears. Comparison between the unenhanced image and the enhanced image under traction avoided mistaking undercutting of the labrum for a tear in 4 hips. Contrast-enhanced MR imaging under traction was valuable for detecting labral tears non-invasively and without radiation. Follow-up examinations using this method in patients with acetabular dysplasia can help to clarify the natural course of labral disorders and enable better treatment planning. (orig./MG)

  2. Contrast-enhanced NMR imaging: animal studies using gadolinium-DTPA complex

    International Nuclear Information System (INIS)

    Brasch, R.C.; Weinmann, H.J.; Wesbey, G.E.

    1984-01-01

    Gadolinium (Gd)-DTPA complex was assessed as a nuclear magnetic resonance (NMR) contrast-enhancing agent by experimentally imaging normal and diseased animals. After intravenous injection, Gd-DTPA, a strongly paramagnetic complex by virtue of unpaired electrons, was rapidly excreted into the urine of rats, producing an easily observable contrast enhancement on NMR images in kidney parenchyma and urine. Sterile soft-tissue abscesses demonstrated an obvious rim pattern of enhancement. A focus of radiation-induced brain damage in a canine model was only faintly detectable on spin-echo NMR images before contrast administration; after 0.5 mmol/kg Gd-DTPA administration, the lesion intensity increased from 3867 to 5590. In comparison, the normal brain with an intact blood-brain barrier remained unchanged in NMR characterization. Gd-DTPA is a promising new NMR contrast enhancer for the clinical assessment of renal function, of inflammatory lesions, and of focal disruption of the blood-brain barrier

  3. Estimation of Tumor Angiogenesis With Contrast Enhanced Subharmonic Ultrasound Imaging

    National Research Council Canada - National Science Library

    Forsberg, Flemming

    2001-01-01

    ...) and receiving at the subharmonic (f0) . Because of no subharmonic generation in tissue and significant subharmonic scattering from some new contrast agents SHI has the potential to detect slow, small volume blood flow associated with tumor...

  4. Contrast-enhanced fat- suppression MR imaging of avascular necrosis of femoral head

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Tae Kyoung; Shim, Jae Chan; Lee, Ghi Jai; Jeon, Jeong Dong; Bang, Sun Woo; Kim, Ho Kyun [College of Medicine, Inje University, Seoul (Korea, Republic of)

    2000-02-01

    To evaluate the findings and role of contrast-enhanced fat suppression MR imaging in avascular necrosis (AVN) of the femoral head. In 15 patients with AVN of the femoral head, MR T1-weighted and T2-weighted images and contrast-enhanced fat-suppression T1-weighted images were obtained, and the findings were reviewed. Early and advanced groups were classified on the basis of clinical findings and imaging, and the enhancement pattern was classified as either type I, rim enhancement; type II, surrounding diffuse enhancement; type III, intralesional enhancement; or type IV, II + III. Twenty-four cases of AVN of the femoral head were detected; in nine patients, lesions were bilateral. Eight cases occurred in the early group and 16 in the advanced. All eight in the early group showed the 'double line sign' on T2-weighted images, with a type-I enhancement pattern. In the advanced group, type II (8/16) and type IV (8/16) enhancement patterns were seen. Among the cases showing the type-IV pattern, the intralesional enhancing area showed low signal intensity on T1-weighted images and isosignal intensity on T2-weighted in one case, and low signal intensity on T2-weighted in one case, and low signal intensity on T1-weighted images and high signal intensity on T2-weighted in the other cases. There was no difference in the extent of the disease before and after enhancement. Contrast-enhanced fat-suppression MR images may be helpful in evaluating the extent of AVN of the femoral head and predicting the histopathologic findings of the disease. (author)

  5. Contrast-enhanced fat- suppression MR imaging of avascular necrosis of femoral head

    International Nuclear Information System (INIS)

    Oh, Tae Kyoung; Shim, Jae Chan; Lee, Ghi Jai; Jeon, Jeong Dong; Bang, Sun Woo; Kim, Ho Kyun

    2000-01-01

    To evaluate the findings and role of contrast-enhanced fat suppression MR imaging in avascular necrosis (AVN) of the femoral head. In 15 patients with AVN of the femoral head, MR T1-weighted and T2-weighted images and contrast-enhanced fat-suppression T1-weighted images were obtained, and the findings were reviewed. Early and advanced groups were classified on the basis of clinical findings and imaging, and the enhancement pattern was classified as either type I, rim enhancement; type II, surrounding diffuse enhancement; type III, intralesional enhancement; or type IV, II + III. Twenty-four cases of AVN of the femoral head were detected; in nine patients, lesions were bilateral. Eight cases occurred in the early group and 16 in the advanced. All eight in the early group showed the 'double line sign' on T2-weighted images, with a type-I enhancement pattern. In the advanced group, type II (8/16) and type IV (8/16) enhancement patterns were seen. Among the cases showing the type-IV pattern, the intralesional enhancing area showed low signal intensity on T1-weighted images and isosignal intensity on T2-weighted in one case, and low signal intensity on T2-weighted in one case, and low signal intensity on T1-weighted images and high signal intensity on T2-weighted in the other cases. There was no difference in the extent of the disease before and after enhancement. Contrast-enhanced fat-suppression MR images may be helpful in evaluating the extent of AVN of the femoral head and predicting the histopathologic findings of the disease. (author)

  6. Contrast-enhanced magnetic resonance imaging for the detection of acute haemorrhagic necrotizing pancreatitis

    International Nuclear Information System (INIS)

    Piironen, A.; Kivisaari, R.; Pitkaeranta, P.; Poutanen, V.P.; Laippala, P.; Laurila, P.; Kivisaari, L.

    1997-01-01

    Eleven piglets with haemorrhagic necrotizing pancreatitis and nine piglets with oedematous pancreatitis were imaged using a multi-breath-hold TurboFLASH (TR 6.5 ms, TE 3 ms, TI 300 ms, flip angle 8 , three slices) pre-excited T1-weighted sequence with an IV bolus injection of gadopentetate dimeglumine (Gd-DTPA, 0.3 mmol/kg) as a contrast agent to show dynamic contrast enhancement of the pancreas by MRI. All piglets were imaged according to the same protocol before inducing the disease. Following the IV Gd-DTPA bolus, time-enhancement curve of the pancreas during haemorrhagic necrotizing pancreatitis was significantly lower than during oedematous pancreatitis. The enhancement curves for the healthy piglets and piglets with oedematous pancreatitis did not differ significantly. Each piglet served as its own control. Because the results of this initial study are similar to those obtained with contrast-enhanced CT, we conclude that our results may encourage further clinical trials, and contrast-enhanced dynamic MRI may be an alternative to the established method of CT for diagnosing acute haemorrhagic necrotizing pancreatitis. (orig.). With 3 figs

  7. Contrast enhancement of bite mark images using the grayscale mixer in ACR in Photoshop®.

    Science.gov (United States)

    Evans, Sam; Noorbhai, Suzanne; Lawson, Zoe; Stacey-Jones, Seren; Carabott, Romina

    2013-05-01

    Enhanced images may improve bite mark edge definition, assisting forensic analysis. Current contrast enhancement involves color extraction, viewing layered images by channel. A novel technique, producing a single enhanced image using the grayscale mix panel within Adobe Camera Raw®, has been developed and assessed here, allowing adjustments of multiple color channels simultaneously. Stage 1 measured RGB values in 72 versions of a color chart image; eight sliders in Photoshop® were adjusted at 25% intervals, all corresponding colors affected. Stage 2 used a bite mark image, and found only red, orange, and yellow sliders had discernable effects. Stage 3 assessed modality preference between color, grayscale, and enhanced images; on average, the 22 survey participants chose the enhanced image as better defined for nine out of 10 bite marks. The study has shown potential benefits for this new technique. However, further research is needed before use in the analysis of bite marks. © 2013 American Academy of Forensic Sciences.

  8. Quantitative imaging by pixel-based contrast-enhanced ultrasound reveals a linear relationship between synovial vascular perfusion and the recruitment of pathogenic IL-17A-F+IL-23+ CD161+ CD4+ T helper cells in psoriatic arthritis joints.

    Science.gov (United States)

    Fiocco, Ugo; Stramare, Roberto; Martini, Veronica; Coran, Alessandro; Caso, Francesco; Costa, Luisa; Felicetti, Mara; Rizzo, Gaia; Tonietto, Matteo; Scanu, Anna; Oliviero, Francesca; Raffeiner, Bernd; Vezzù, Maristella; Lunardi, Francesca; Scarpa, Raffaele; Sacerdoti, David; Rubaltelli, Leopoldo; Punzi, Leonardo; Doria, Andrea; Grisan, Enrico

    2017-02-01

    To develop quantitative imaging biomarkers of synovial tissue perfusion by pixel-based contrast-enhanced ultrasound (CEUS), we studied the relationship between CEUS synovial vascular perfusion and the frequencies of pathogenic T helper (Th)-17 cells in psoriatic arthritis (PsA) joints. Eight consecutive patients with PsA were enrolled in this study. Gray scale CEUS evaluation was performed on the same joint immediately after joint aspiration, by automatic assessment perfusion data, using a new quantification approach of pixel-based analysis and the gamma-variate model. The set of perfusional parameters considered by the time intensity curve includes the maximum value (peak) of the signal intensity curve, the blood volume index or area under the curve, (BVI, AUC) and the contrast mean transit time (MTT). The direct ex vivo analysis of the frequencies of SF IL17A-F + CD161 + IL23 + CD4 + T cells subsets were quantified by fluorescence-activated cell sorter (FACS). In cross-sectional analyses, when tested for multiple comparison setting, a false discovery rate at 10%, a common pattern of correlations between CEUS Peak, AUC (BVI) and MTT parameters with the IL17A-F + IL23 + - IL17A-F + CD161 + - and IL17A-F + CD161 + IL23 + CD4 + T cells subsets, as well as lack of correlation between both peak and AUC values and both CD4 + T and CD4 + IL23 + T cells, was observed. The pixel-based CEUS assessment is a truly measure synovial inflammation, as a useful tool to develop quantitative imaging biomarker for monitoring target therapeutics in PsA.

  9. MR imaging of the early rheumatoid arthritis: usefulness of contrast enhanced fat suppressed SPGR imaging

    International Nuclear Information System (INIS)

    Kim, Sun Mi; Joo, Kyung Bin; Kim, Seong Tae; Hahm, Chang Kok

    1995-01-01

    To evaluate value of post-contrast 3-Dimensional fat suppressed Spoiled GRASS (FS SPGR) in detecting subtle bony erosion and tenosynovitis of hands and wrists due to early rheumatoid arthritis. Fourteen MR imagings of the hands and wrists were performed in 7 early rheumatoid arthritis without any abnormalities in plain radiography and in 7 healthy volunteers. All subjects underwent MR sequence of coronal 3D FS SPGR with and without contrast enhancement in 1.5T MR unit. We evaluated the number of the bony erosion and tenosynovitis respectively in pre-and post-contrast FS SPGR images. The abnormal enhancing areas were not demonstrated in 7 healthy volunteers. Seven patients had 25 bony erosions in pre-contrast FS SPGR and 52 bony erosions with tenosynovitis (n = 10) in post-contrast FS SPGR. Enhancing joint spaces were shown in 8 cases. Post-contrast FS SPGR was better than pre-contrast FS SPGR in the evaluation of early rheumatoid arthritis and is valuable as a baseline study

  10. MR imaging of the early rheumatoid arthritis: usefulness of contrast enhanced fat suppressed SPGR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sun Mi; Joo, Kyung Bin; Kim, Seong Tae; Hahm, Chang Kok [College of Medicine, Hanyang University, Seoul (Korea, Republic of)

    1995-06-15

    To evaluate value of post-contrast 3-Dimensional fat suppressed Spoiled GRASS (FS SPGR) in detecting subtle bony erosion and tenosynovitis of hands and wrists due to early rheumatoid arthritis. Fourteen MR imagings of the hands and wrists were performed in 7 early rheumatoid arthritis without any abnormalities in plain radiography and in 7 healthy volunteers. All subjects underwent MR sequence of coronal 3D FS SPGR with and without contrast enhancement in 1.5T MR unit. We evaluated the number of the bony erosion and tenosynovitis respectively in pre-and post-contrast FS SPGR images. The abnormal enhancing areas were not demonstrated in 7 healthy volunteers. Seven patients had 25 bony erosions in pre-contrast FS SPGR and 52 bony erosions with tenosynovitis (n = 10) in post-contrast FS SPGR. Enhancing joint spaces were shown in 8 cases. Post-contrast FS SPGR was better than pre-contrast FS SPGR in the evaluation of early rheumatoid arthritis and is valuable as a baseline study.

  11. Differential evolution optimization combined with chaotic sequences for image contrast enhancement

    Energy Technology Data Exchange (ETDEWEB)

    Santos Coelho, Leandro dos [Industrial and Systems Engineering Graduate Program, LAS/PPGEPS, Pontifical Catholic University of Parana, PUCPR Imaculada Conceicao, 1155, 80215-901 Curitiba, Parana (Brazil)], E-mail: leandro.coelho@pucpr.br; Sauer, Joao Guilherme [Industrial and Systems Engineering Graduate Program, LAS/PPGEPS, Pontifical Catholic University of Parana, PUCPR Imaculada Conceicao, 1155, 80215-901 Curitiba, Parana (Brazil)], E-mail: joao.sauer@gmail.com; Rudek, Marcelo [Industrial and Systems Engineering Graduate Program, LAS/PPGEPS, Pontifical Catholic University of Parana, PUCPR Imaculada Conceicao, 1155, 80215-901 Curitiba, Parana (Brazil)], E-mail: marcelo.rudek@pucpr.br

    2009-10-15

    Evolutionary Algorithms (EAs) are stochastic and robust meta-heuristics of evolutionary computation field useful to solve optimization problems in image processing applications. Recently, as special mechanism to avoid being trapped in local minimum, the ergodicity property of chaotic sequences has been used in various designs of EAs. Three differential evolution approaches based on chaotic sequences using logistic equation for image enhancement process are proposed in this paper. Differential evolution is a simple yet powerful evolutionary optimization algorithm that has been successfully used in solving continuous problems. The proposed chaotic differential evolution schemes have fast convergence rate but also maintain the diversity of the population so as to escape from local optima. In this paper, the image contrast enhancement is approached as a constrained nonlinear optimization problem. The objective of the proposed chaotic differential evolution schemes is to maximize the fitness criterion in order to enhance the contrast and detail in the image by adapting the parameters using a contrast enhancement technique. The proposed chaotic differential evolution schemes are compared with classical differential evolution to two testing images. Simulation results on three images show that the application of chaotic sequences instead of random sequences is a possible strategy to improve the performance of classical differential evolution optimization algorithm.

  12. Variational contrast enhancement guided by global and local contrast measurements for single-image defogging

    Science.gov (United States)

    Zhou, Li; Bi, Du-Yan; He, Lin-Yuan

    2015-01-01

    The visibility of images captured in foggy conditions is impaired severely by a decrease in the contrasts of objects and veiling with a characteristic gray hue, which may limit the performance of visual applications out of doors. Contrast enhancement together with color restoration is a challenging mission for conventional fog-removal methods, as the degrading effect of fog is largely dependent on scene depth information. Nowadays, people change their minds by establishing a variational framework for contrast enhancement based on a physically based analytical model, unexpectedly resulting in color distortion, dark-patch distortion, or fuzzy features of local regions. Unlike previous work, our method treats an atmospheric veil as a scattering disturbance and formulates a foggy image as an energy functional minimization to estimate direct attenuation, originating from the work of image denoising. In addition to a global contrast measurement based on a total variation norm, an additional local measurement is designed in that optimal problem for the purpose of digging out more local details as well as suppressing dark-patch distortion. Moreover, we estimate the airlight precisely by maximization with a geometric constraint and a natural image prior in order to protect the faithfulness of the scene color. With the estimated direct attenuation and airlight, the fog-free image can be restored. Finally, our method is tested on several benchmark and realistic images evaluated by two assessment approaches. The experimental results imply that our proposed method works well compared with the state-of-the-art defogging methods.

  13. Contrast-Enhanced MR Imaging of Lymph Nodes in Cancer Patients

    International Nuclear Information System (INIS)

    Choi, Seung Hong; Moon, Woo Kyung

    2010-01-01

    The accurate identification and characterization of lymph nodes by modern imaging modalities has important therapeutic and prognostic significance for patients with newly diagnosed cancers. The presence of nodal metastases limits the therapeutic options, and it generally indicates a worse prognosis for the patients with nodal metastases. Yet anatomic imaging (CT and MR imaging) is of limited value for depicting small metastatic deposits in normal-sized nodes, and nodal size is a poor criterion when there is no extracapsular extension or focal nodal necrosis to rely on for diagnosing nodal metastases. Thus, there is a need for functional methods that can be reliably used to identify small metastases. Contrast-enhanced MR imaging of lymph nodes is a non-invasive method for the analysis of the lymphatic system after the interstitial or intravenous administration of contrast media. Moreover, some lymphotrophic contrast media have been developed and used for detecting lymph node metastases, and this detection is independent of the nodal size. This article will review the basic principles, the imaging protocols, the interpretation and the accuracies of contrast-enhanced MR imaging of lymph nodes in patients with malignancies, and we also focus on the recent issues cited in the literature. In addition, we discuss the results of several pre-clinical studies and animal studies that were conducted in our institution

  14. Rational Variety Mapping for Contrast-Enhanced Nonlinear Unsupervised Segmentation of Multispectral Images of Unstained Specimen

    Science.gov (United States)

    Kopriva, Ivica; Hadžija, Mirko; Popović Hadžija, Marijana; Korolija, Marina; Cichocki, Andrzej

    2011-01-01

    A methodology is proposed for nonlinear contrast-enhanced unsupervised segmentation of multispectral (color) microscopy images of principally unstained specimens. The methodology exploits spectral diversity and spatial sparseness to find anatomical differences between materials (cells, nuclei, and background) present in the image. It consists of rth-order rational variety mapping (RVM) followed by matrix/tensor factorization. Sparseness constraint implies duality between nonlinear unsupervised segmentation and multiclass pattern assignment problems. Classes not linearly separable in the original input space become separable with high probability in the higher-dimensional mapped space. Hence, RVM mapping has two advantages: it takes implicitly into account nonlinearities present in the image (ie, they are not required to be known) and it increases spectral diversity (ie, contrast) between materials, due to increased dimensionality of the mapped space. This is expected to improve performance of systems for automated classification and analysis of microscopic histopathological images. The methodology was validated using RVM of the second and third orders of the experimental multispectral microscopy images of unstained sciatic nerve fibers (nervus ischiadicus) and of unstained white pulp in the spleen tissue, compared with a manually defined ground truth labeled by two trained pathophysiologists. The methodology can also be useful for additional contrast enhancement of images of stained specimens. PMID:21708116

  15. Preliminary study of single contrast enhanced dual energy heart imaging using dual-source CT

    International Nuclear Information System (INIS)

    Peng Jin; Zhang Longjiang; Zhou Changsheng; Lu Guangming; Ma Yan; Gu Haifeng

    2009-01-01

    Objective: To evaluate the feasibility and preliminary applications of single contrast enhanced dual energy heart imaging using dual-source CT (DSCT). Methods: Thirty patients underwent dual energy heart imaging with DSCT, of which 6 cases underwent SPECT or DSA within one week. Two experienced radiologists assessed image quality of coronary arteries and iodine map of myocardium. and correlated the coronary artery stenosis with the perfusion distribution of iodine map. Results: l00% (300/300) segments reached diagnostic standards. The mean score of image for all patients was 4.68±0.57. Mural coronary artery was present in 10 segments in S cases, atherosclerotic plaques in 32 segments in 12 cases, of which 20 segments having ≥50% stenosis, 12 segments ≤50% stenosis; dual energy CT coronary angiography was consistent with the DSA in 3 patients. 37 segmental perfusion abnormalities on iodine map were found in 15 cases, including 28 coronary blood supply segment narrow segment and 9 no coronary stenosis (including three negative segments in SPECD. Conclusion: Single contrast enhanced dual energy heart imaging can provide good coronary artery and myocardium perfusion images in the patients with appropriate heart rate, which has a potential to be used in the clinic and further studies are needed. (authors)

  16. Diagnostic Accuracy of Dynamic Contrast Enhanced Magnetic Resonance Imaging in Characterizing Lung Masses

    Science.gov (United States)

    Inan, Nagihan; Arslan, Arzu; Donmez, Muhammed; Sarisoy, Hasan Tahsin

    2016-01-01

    Background Imaging plays a critical role not only in the detection, but also in the characterization of lung masses as benign or malignant. Objectives To determine the diagnostic accuracy of dynamic magnetic resonance imaging (MRI) in the differential diagnosis of benign and malignant lung masses. Patients and Methods Ninety-four masses were included in this prospective study. Five dynamic series of T1-weighted spoiled gradient echo (FFE) images were obtained, followed by a T1-weighted FFE sequence in the late phase (5th minutes). Contrast enhancement patterns in the early (25th second) and late (5th minute) phase images were evaluated. For the quantitative evaluation, signal intensity (SI)-time curves were obtained and the maximum relative enhancement, wash-in rate, and time-to-peak enhancement of masses in both groups were calculated. Results The early phase contrast enhancement patterns were homogeneous in 78.2% of the benign masses, while heterogeneous in 74.4% of the malignant tumors. On the late phase images, 70.8% of the benign masses showed homogeneous enhancement, while most of the malignant masses showed heterogeneous enhancement (82.4%). During the first pass, the maximum relative enhancement and wash-in rate values of malignant masses were significantly higher than those of the benign masses (P = 0.03 and 0.04, respectively). The cutoff value at 15% yielded a sensitivity of 85.4%, specificity of 61.2%, and positive predictive value of 68.7% for the maximum relative enhancement. Conclusion Contrast enhancement patterns and SI-time curve analysis of MRI are helpful in the differential diagnosis of benign and malignant lung masses. PMID:27703654

  17. Contrast-enhanced voiding urosonography: in vitro evaluation of a second-generation ultrasound contrast agent for in vivo optimization.

    Science.gov (United States)

    Back, Susan J; Edgar, J Christopher; Canning, Douglas A; Darge, Kassa

    2015-09-01

    Pediatric contrast-enhanced ultrasound (CEUS) is primarily performed outside the United States where a track record for safety in intravenous and intravesical applications has been established. Contrast-enhanced voiding urosonography (ceVUS) has also been shown to have a much higher rate of vesicoureteral reflux detection compared to voiding cystourethrography. US contrast agents available in the United States differ from those abroad. Optison® (GE Healthcare, Princeton, NJ) is such an US contrast agent. While Optison® has similar characteristics to other second-generation agents, it has never been used for ceVUS. In vitro optimization of dose and imaging parameters as well as assessment of contrast visualization when delivered in conditions similar to ceVUS are necessary starting points prior to in vivo applications. To optimize the intravesical use of Optison® in vitro for ceVUS before its use in pediatric studies. The experimental design simulated intravesical use. Using 9- and 12-MHz linear transducers, we scanned 20-mL syringes varying mechanical index, US contrast agent concentration (0.25%, 0.5%, 1.0%), solvent (saline, urine, radiographic contrast agent) and time out of refrigeration. We evaluated mechanical index settings and contrast duration, optimized the contrast dose, measured the effect of urine and radiographic contrast agent, and the impact of length of time of contrast outside of the refrigerator on US contrast appearance. We scanned 50-ml saline bags to assess the appearance and duration of US contrast with different delivery systems (injection vs. infusion). Consistent contrast visualization was achieved at a mechanical index of 0.06-0.17 and 0.11-0.48 for the L9 and L12 MHz transducers (P contrast visualization of the microbubbles with a higher transducer frequency. The lowest mechanical index for earliest visible microbubble destruction was 0.21 for the 9 MHz and 0.39 for the 12 MHz (P contrast agent volume to bladder filling was the

  18. The value of contrast-enhanced laparoscopic ultrasound during robotic-assisted surgery for primary colorectal cancer

    DEFF Research Database (Denmark)

    Ellebaek, Signe Bremholm; Fristrup, Claus Wilki; Pless, Torsten

    2018-01-01

    AIM: The aim of this study was to assess the potential clinical value of contrast enhanced laparoscopic ultrasonography (CE-LUS) as a screening modality for liver metastases during robotic assisted surgery for primary colorectal cancer (CRC). METHOD: A prospective, descriptive (feasibility) study...... including 50 consecutive patients scheduled for robotic assisted surgery for primary CRC. CE-LUS was performed by 2 experienced specialists. Only patients without metastatic disease were included. Follow-up was obtained with contrast-enhanced CT imaging at 3 and 12 months postoperatively. RESULTS: Fifty......-up revealed no liver metastasis in any of the patients. CONCLUSION: CE-LUS did not increase the detection rate of occult liver metastasis during robotic assisted primary CRC surgery. The use of CE-LUS as a screening modality for detection of liver metastasis cannot be recommended based on this study...

  19. Non-contrast-enhanced imaging of haemodialysis fistulas using quiescent-interval single-shot (QISS) MRA: a feasibility study

    International Nuclear Information System (INIS)

    Okur, A.; Kantarci, M.; Karaca, L.; Yildiz, S.; Sade, R.; Pirimoglu, B.; Keles, M.; Avci, A.; Çankaya, E.; Schmitt, P.

    2016-01-01

    Aim: To assess the efficiency of a novel quiescent-interval single-shot (QISS) technique for non-contrast-enhanced magnetic resonance angiography (MRA) of haemodialysis fistulas. Materials and methods: QISS MRA and colour Doppler ultrasound (CDU) images were obtained from 22 haemodialysis patients with end-stage renal disease (ESRD). A radiologist with extensive experience in vascular imaging initially assessed the fistulas using CDU. Two observers analysed each QISS MRA data set in terms of image quality, using a five-point scale ranging from 0 (non-diagnostic) to 4 (excellent), and lumen diameters of all segments were measured. Results: One hundred vascular segments were analysed for QISS MRA. Two anastomosis segments were considered non-diagnostic. None of the arterial or venous segments were evaluated as non-diagnostic. The image quality was poorer for the anastomosis level compared to the other segments (p<0.001 for arterial segments, and p<0.05 for venous segments), while no significant difference was determined for other vascular segments. Conclusion: QISS MRA has the potential to provide valuable complementary information to CDU regarding the imaging of haemodialysis fistulas. In addition, QISS non-enhanced MRA represents an alternative for assessment of haemodialysis fistulas, in which the administration of iodinated or gadolinium-based contrast agents is contraindicated. - Highlights: • Close monitoring and early intervention in hemodialysis fistulas may prolong longevity fistulas. • DopplerUS, contrast enhanced CT and MRI are using assessment of hemodialysis fistulas. • QISS nonenhanced MR angiography represents an alternative for assessment of hemodialysis fistulas.

  20. A new combined technique for automatic contrast enhancement of digital images

    Directory of Open Access Journals (Sweden)

    Ismail A. Humied

    2012-03-01

    Full Text Available Some low contrast images have certain characteristics makes it difficult to use traditional methods to improve it. An example of these characteristics, that the amplitudes of images histogram components are very high at one location on the gray scale and very small in the rest of the gray scale. In the present paper, a new method is described. It can deal with such cases. The proposed method is a combination of Histogram Equalization (HE and Fast Gray-Level Grouping (FGLG. The basic procedure of this method is segments the original histogram of a low contrast image into two sub-histograms according to the location of the highest amplitude of the histogram components, and achieving contrast enhancement by equalizing the left segment of the histogram components using (HE technique and using (FGLG technique to equalize the right segment of this histogram components. The results have shown that the proposed method does not only produce better results than each individual contrast enhancement technique, but it is also fully automated. Moreover, it is applicable to a broad variety of images that satisfy the properties mentioned above and suffer from low contrast.

  1. Temporomandibular joint (TMJ) pain revisited with dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI)

    International Nuclear Information System (INIS)

    Tasali, N.; Cubuk, R.; Aricak, M.; Ozarar, M.; Saydam, B.; Nur, H.; Tuncbilek, N.

    2012-01-01

    Purpose: We aimed to assess the contrast enhancement patterns of the retrodiscal tissue with dynamic contrast-enhanced MR imaging (DCE-MRI) with respect to different temporomandibular joint disc pathologies. Additionally, we questioned the relationship between the temporomandibular joint (TMJ) pain and the contrast enhancement pattern of the retrodiscal tissue regardless of the TMJ disc position. Materials and methods: 52 joints of 26 patients (4 males and 22 females) who have pain in at least at one of their TMJ were included in this study. For the qualitative analysis, the joints were divided into four groups in terms of their disc positions: normal (1), partially displaced with or without reduction (2), totally dislocated with reduction (3) and totally dislocated without reduction (4). Besides, two different joint groups were constituted, namely the painful group and painless group according to the clinical findings without taking the TMJ disc positions into account. Quantitative analyses were made by means of measuring signal intensity ratios (SI) ratio at the retrodiscal tissue (from internal side and external side of the each joint) using DCE-MRI and these measurements were analyzed with paired samples t test to define the difference between the measurements. At the second stage, the time-dependent arithmetical mean values of the SI ratios were calculated for each joint group and significant differences between the groups were questioned using analysis of variance (ANOVA) test. Besides, painful and painless groups which were classified on the basis of the clinical data were compared according to the mean SI ratios found for each joint and the significant differences between these two groups were assessed by means of Student's T test. The results were assessed in 95% confidence interval where the significance level was p < 0.05. Results: A significant difference was observed between the internal and external contrast enhancement of the joints with partial

  2. Contrast-enhanced ultrasound evaluation of hepatic microvascular changes in liver diseases.

    Science.gov (United States)

    Ridolfi, Francesco; Abbattista, Teresa; Busilacchi, Paolo; Brunelli, Eugenio

    2012-10-07

    To assess if software assisted-contrast-enhanced ultrasonography (CEUS) provides reproducible perfusion parameters of hepatic parenchyma in patients affected by chronic liver disease. Forty patients with chronic viral liver disease, with (n = 20) or without (n = 20) cirrhosis, and 10 healthy subjects underwent CEUS and video recordings of each examination were then analysed with Esaote's Qontrast software. CEUS dedicated software Qontrast was used to determine peak (the maximum signal intensity), time to peak (TTP), region of blood value (RBV) proportional to the area under the time-intensity curve, mean transit time (MTT) measured in seconds and region of blood flow (RBF). Qontrast-assisted CEUS parameters displayed high inter-observer reproducibility (κ coefficients of 0.87 for MTT and 0.90 TTP). When the region of interest included a main hepatic vein, Qontrast-calculated TTP was significantly shorter in cirrhotic patients (vs non-cirrhotics and healthy subjects) (71.0 ± 11.3 s vs. 82.4 ± 15.6 s, 86.3 ± 20.3 s, P < 0.05). MTTs in the patients with liver cirrhosis were significantly shorter than those of controls (111.9 ± 22.0 s vs. 139.4 ± 39.8 s, P < 0.05), but there was no significant difference between the cirrhotic and non-cirrhotic groups (111.9 ± 22.0 s vs. 110.3 ± 14.6 s). Peak enhancement in the patients with liver cirrhosis was also higher than that observed in controls (23.9 ± 5.9 vs. 18.9 ± 7.1, P = 0.05). There were no significant intergroup differences in the RBVs and RBFs. Qontrast-assisted CEUS revealed reproducible differences in liver perfusion parameters during the development of hepatic fibrogenesis.

  3. Ewing's sarcoma recurrence vs radiation necrosis in dynamic contrast-enhanced MR imaging: a case report

    International Nuclear Information System (INIS)

    El Khadrawy, A.M.; Hoffer, F.A.; Reddick, W.E.

    1999-01-01

    Purpose. We report a case of Ewing's sarcoma in the right distal femur in a 6-year-old male to demonstrate how dynamic contrast-enhanced magnetic resonance imaging (DEMRI) findings predicted histopathology. Materials and methods. DEMRI was performed at presentation and during and after completion of chemotherapy and radiation therapy. Histopathologic studies were done at presentation, at 77 weeks (20 weeks after a pathological fracture), and from the en bloc resection at 104 weeks. Results. DEMRI predicted the early tumor response, absence of tumor recurrence, presence of necrosis and lack of fracture healing, confirmed by histopathology. Conclusion. DEMRI is a clinically useful tool in managing Ewing's sarcoma. (orig.)

  4. Applicability of contrast-enhanced ultrasound in the diagnosis of plantar fasciitis

    DEFF Research Database (Denmark)

    Broholm, Rikke; Pingel, Jessica; Simonsen, Lene

    2017-01-01

    -mode ultrasound (US) in patients with plantar fasciitis (PF). 20 patients with unilateral PF were included and were divided by US in insertional thickening (10), midsubstance thickening (5) and no US changes (5). The MV was measured simultaneously in both heels. Four areas in the plantar fascia and plantar fat...... pad were measured independently by two observers. Inter- and intra-observer correlation analyses were performed. The asymptomatic heels showed a constantly low MV, and for the whole group of patients a significantly higher MV was found in the symptomatic plantar fascia and plantar fat pad. Inter...

  5. 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 ...

  6. Automated Detection of Healthy and Diseased Aortae from Images Obtained by Contrast-Enhanced CT Scan

    Directory of Open Access Journals (Sweden)

    Michael Gayhart

    2013-01-01

    Full Text Available Purpose. We developed the next stage of our computer assisted diagnosis (CAD system to aid radiologists in evaluating CT images for aortic disease by removing innocuous images and highlighting signs of aortic disease. Materials and Methods. Segmented data of patient’s contrast-enhanced CT scan was analyzed for aortic dissection and penetrating aortic ulcer (PAU. Aortic dissection was detected by checking for an abnormal shape of the aorta using edge oriented methods. PAU was recognized through abnormally high intensities with interest point operators. Results. The aortic dissection detection process had a sensitivity of 0.8218 and a specificity of 0.9907. The PAU detection process scored a sensitivity of 0.7587 and a specificity of 0.9700. Conclusion. The aortic dissection detection process and the PAU detection process were successful in removing innocuous images, but additional methods are necessary for improving recognition of images with aortic disease.

  7. Variability induced by the MR imager in dynamic contrast-enhanced imaging of the prostate.

    Science.gov (United States)

    Brunelle, S; Zemmour, C; Bratan, F; Mège-Lechevallier, F; Ruffion, A; Colombel, M; Crouzet, S; Sarran, A; Rouvière, O

    2018-04-01

    To evaluate the variability induced by the imager in discriminating high-grade (Gleason≥7) prostate cancers (HGC) using dynamic contrast-enhanced MRI. We retrospectively selected 3T MRIs with temporal resolution<10 seconds and comprising T1 mapping from a prospective radiologic-pathologic database of patients treated by prostatectomy. Ktrans, Kep, Ve and Vp were calculated for each lesion seen on MRI using the Weinmann arterial input function (AIF) and three patient-specific AIFs measured in the right and left iliac arteries in pixels in the center of the lumen (psAIF-ST) or manually selected by two independent readers (psAIF-R1 and psAIF-R2). A total of 43 patients (mean age, 63.6±4.9 [SD]; range: 48-72 years) with 100 lesions on MRI (55 HGC) were selected. MRIs were performed on imager A (22 patients, 49 lesions) or B (21 patients, 51 lesions) from two different manufacturers. Using the Weinmann AIF, Kep (P=0.005), Ve (P=0.04) and Vp (P=0.01) significantly discriminated HCG. After adjusting on tissue classes, the imager significantly influenced the values of Kep (P=0.049) and Ve (P=0.007). Using patient-specific AIFs, Vp with psAIF-ST (P=0.008) and psAIF-R2 (P=0.04), and Kep with psAIF-R1 (P=0.03) significantly discriminated HGC. After adjusting on tissue classes, types of patient-specific AIF and side of measurement, the imager significantly influenced the values of Ktrans (P=0.0002), Ve (P=0.0072) and Vp (P=0.0003). For all AIFs, the diagnostic value of pharmacokinetic parameters remained unchanged after adjustment on the imager, with stable odds ratios. The imager induced variability in the absolute values of pharmacokinetic parameters but did not change their diagnostic performance. Copyright © 2018 Société française de radiologie. Published by Elsevier Masson SAS. All rights reserved.

  8. Generalized image contrast enhancement technique based on Heinemann contrast discrimination model

    Science.gov (United States)

    Liu, Hong; Nodine, Calvin F.

    1994-03-01

    This paper presents a generalized image contrast enhancement technique which equalizes perceived brightness based on the Heinemann contrast discrimination model. This is a modified algorithm which presents an improvement over the previous study by Mokrane in its mathematically proven existence of a unique solution and in its easily tunable parameterization. The model uses a log-log representation of contrast luminosity between targets and the surround in a fixed luminosity background setting. The algorithm consists of two nonlinear gray-scale mapping functions which have seven parameters, two of which are adjustable Heinemann constants. Another parameter is the background gray level. The remaining four parameters are nonlinear functions of gray scale distribution of the image, and can be uniquely determined once the previous three are given. Tests have been carried out to examine the effectiveness of the algorithm for increasing the overall contrast of images. It can be demonstrated that the generalized algorithm provides better contrast enhancement than histogram equalization. In fact, the histogram equalization technique is a special case of the proposed mapping.

  9. Quantitative evaluation of contrast-enhanced ultrasound after intravenous administration of a microbubble contrast agent for differentiation of benign and malignant thyroid nodules: assessment of diagnostic accuracy.

    Science.gov (United States)

    Nemec, Ursula; Nemec, Stefan F; Novotny, Clemens; Weber, Michael; Czerny, Christian; Krestan, Christian R

    2012-06-01

    To investigate the diagnostic accuracy, through quantitative analysis, of contrast-enhanced ultrasound (CEUS), using a microbubble contrast agent, in the differentiation of thyroid nodules. This prospective study enrolled 46 patients with solitary, scintigraphically non-functional thyroid nodules. These patients were scheduled for surgery and underwent preoperative CEUS with pulse-inversion harmonic imaging after intravenous microbubble contrast medium administration. Using histology as a standard of reference, time-intensity curves of benign and malignant nodules were compared by means of peak enhancement and wash-out enhancement relative to the baseline intensity using a mixed model ANOVA. ROC analysis was performed to assess the diagnostic accuracy in the differentiation of benign and malignant nodules on CEUS. The complete CEUS data of 42 patients (31/42 [73.8%] benign and 11/42 [26.2%] malignant nodules) revealed a significant difference (P benign and malignant nodules. Furthermore, based on ROC analysis, CEUS demonstrated sensitivity of 76.9%, specificity of 84.8% and accuracy of 82.6%. Quantitative analysis of CEUS using a microbubble contrast agent allows the differentiation of benign and malignant thyroid nodules and may potentially serve, in addition to grey-scale and Doppler ultrasound, as an adjunctive tool in the assessment of patients with thyroid nodules. • Contrast-enhanced ultrasound (CEUS) helps differentiate between benign and malignant thyroid nodules. • Quantitative CEUS analysis yields sensitivity of 76.9% and specificity of 84.8%. • CEUS may be a potentially useful adjunct in assessing thyroid nodules.

  10. Contrast enhanced MR imaging of postoperative medulloblastoma in childhood: emphasis on meningeal enhancement

    International Nuclear Information System (INIS)

    Choi, Choong Gon; Kim, In One; Kim, Woo Sun; Kim, Ho Chul; Yeon, Kyung Mo

    1993-01-01

    To differentiate the postoperative changes from the recurrence of tumor and to evaluate MR imaging of early postoperative leptomeningeal seeding in medulloblastoma, We have retrospectively analysed 34 cases of MR images of 17 patients who were confirmed as medulloblastoma by histopathology. Noncontrast and postcontrast T1 weighted MR images were obtained in all patients. In 11 patients follow-up MR was done more than once (average: 1.5 times) and average interval of MR imaging was 6 months. The timing of 34 MR images was as follow: 6 case within 2 months, 9 cases between 2 months and 1 year, 19 cases more than 1 year after surgery respectively. MR images within 2 month after surgery revealed contrast enhancement at operation site and adjacent meninges, hemorrhage, residual tumor. In patients who had no evidence of tumor recurrence, these early postoperative changes were markedly decreased within 6 month after surgery. MR images obtained more than 1 year after surgery showed no abnormal contrast enhancement or mild focal dural enhancement at operation site. Diffuse moderate dural enhancement was noted in one patient who had the history of post-surgical subdural hemorrhage. In six patients with tumor recurrences which were detected from as early as 9 months to 6 years after surgery, the findings of recurrence included leptomeningeal enhancement of brain stem and cerebellar surface at early stage, variable sized enhancing leptomeningeal nodules, linear or irregular sulcus obliterating enhancing lesions, enhancing mass at primary or metastatic site. We have concluded that leptomeningeal enhancement detected after 6 months of surgery is an important MR finding suggesting the possibility of tumor recurrence. Small nodular and linear enhancement of leptomeninges at brainstem or cerebellar surface is considered as the early manifestation of intracranial tumor seeding

  11. Contrast enhanced MR imaging of postoperative medulloblastoma in childhood: emphasis on meningeal enhancement

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Choong Gon; Kim, In One; Kim, Woo Sun; Kim, Ho Chul; Yeon, Kyung Mo [College of Medicine, Seoul National University, Seoul (Korea, Republic of)

    1993-03-15

    To differentiate the postoperative changes from the recurrence of tumor and to evaluate MR imaging of early postoperative leptomeningeal seeding in medulloblastoma, We have retrospectively analysed 34 cases of MR images of 17 patients who were confirmed as medulloblastoma by histopathology. Noncontrast and postcontrast T1 weighted MR images were obtained in all patients. In 11 patients follow-up MR was done more than once (average: 1.5 times) and average interval of MR imaging was 6 months. The timing of 34 MR images was as follow: 6 case within 2 months, 9 cases between 2 months and 1 year, 19 cases more than 1 year after surgery respectively. MR images within 2 month after surgery revealed contrast enhancement at operation site and adjacent meninges, hemorrhage, residual tumor. In patients who had no evidence of tumor recurrence, these early postoperative changes were markedly decreased within 6 month after surgery. MR images obtained more than 1 year after surgery showed no abnormal contrast enhancement or mild focal dural enhancement at operation site. Diffuse moderate dural enhancement was noted in one patient who had the history of post-surgical subdural hemorrhage. In six patients with tumor recurrences which were detected from as early as 9 months to 6 years after surgery, the findings of recurrence included leptomeningeal enhancement of brain stem and cerebellar surface at early stage, variable sized enhancing leptomeningeal nodules, linear or irregular sulcus obliterating enhancing lesions, enhancing mass at primary or metastatic site. We have concluded that leptomeningeal enhancement detected after 6 months of surgery is an important MR finding suggesting the possibility of tumor recurrence. Small nodular and linear enhancement of leptomeninges at brainstem or cerebellar surface is considered as the early manifestation of intracranial tumor seeding.

  12. 3D Modeling of Vascular Pathologies from contrast enhanced magnetic resonance images (MRI)

    International Nuclear Information System (INIS)

    Cantor Rivera, Diego; Orkisz, Maciej; Arias, Julian; Uriza, Luis Felipe

    2007-01-01

    This paper presents a method for generating 3D vascular models from contrast enhanced magnetic resonance images (MRI) using a fast marching algorithm. The main contributions of this work are: the use of the original image for defining a speed function (which determines the movement of the interface) and the calculation of the time in which the interface identifies the artery. The proposed method was validated on pathologic carotid artery images of patients and vascular phantoms. A visual appraisal of vascular models obtained with the method shows a satisfactory extraction of the vascular wall. A quantitative assessment proved that the generated models depend on the values of algorithm parameters. The maximum induced error was equal to 1.34 voxels in the diameter of the measured stenoses.

  13. Intra-biliary contrast-enhanced ultrasound for evaluating biliary obstruction during percutaneous transhepatic biliary drainage: A preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Er-jiao [Department of Medical Ultrasonics, The Third Affiliated Hospital of Sun Yat-sen University, No. 600 Tianhe Road, Guangzhou 510630 (China); Zheng, Rong-qin, E-mail: zhengrq@mail.sysu.edu.cn [Department of Medical Ultrasonics, The Third Affiliated Hospital of Sun Yat-sen University, No. 600 Tianhe Road, Guangzhou 510630 (China); Su, Zhong-zhen; Li, Kai; Ren, Jie; Guo, Huan-yi [Department of Medical Ultrasonics, The Third Affiliated Hospital of Sun Yat-sen University, No. 600 Tianhe Road, Guangzhou 510630 (China)

    2012-12-15

    Objectives: The aimed of this study was to investigate the value of intra-biliary contrast-enhanced ultrasound (IB-CEUS) for evaluating biliary obstruction during percutaneous transhepatic biliary drainage (PTBD). Materials and methods: 80 patients with obstructive jaundice who underwent IB-CEUS during PTBD were enrolled. The diluted ultrasound contrast agent was injected via the drainage catheter to perform IB-CEUS. Both conventional ultrasound and IB-CEUS were used to detect the tips of the drainage catheters and to compare the detection rates of the tips. The obstructive level and degree of biliary tract were evaluated by IB-CEUS. Fluoroscopic cholangiography (FC) and computer tomography cholangiography (CTC) were taken as standard reference for comparison. Results: Conventional ultrasound displayed only 43 tips (43/80, 53.8%) of the drainage catheters within the bile ducts while IB-CEUS identified all 80 tips (80/80, 100%) of the drainage catheters including 4 of them out of the bile duct (P < 0.001). IB-CEUS made correct diagnosis in 44 patients with intrahepatic and 36 patients with extrahepatic biliary obstructions. IB-CEUS accurately demonstrated complete obstruction in 56 patients and incomplete obstruction in 21 patients. There were 3 patients with incomplete obstruction misdiagnosed to be complete obstruction by IB-CEUS. The diagnostic accuracy of biliary obstruction degree was 96.3% (77/80). Conclusion: IB-CEUS could improve the visualization of the drainage catheters and evaluate the biliary obstructive level and degree during PTBD. IB-CEUS may be the potential substitute to FC in the PTBD procedure.

  14. General Ultrasound Imaging

    Medline Plus

    Full Text Available ... Index A-Z General Ultrasound Ultrasound imaging uses sound waves to produce pictures of the inside of ... pictures of the inside of the body using sound waves. Ultrasound imaging, also called ultrasound scanning or ...

  15. General Ultrasound Imaging

    Medline Plus

    Full Text Available ... What are the limitations of General Ultrasound Imaging? What is General Ultrasound Imaging? Ultrasound is safe and ... be heard with every heartbeat. top of page What are some common uses of the procedure? Ultrasound ...

  16. Differentiation between early rheumatoid arthritis patients and healthy persons by conventional and dynamic contrast-enhanced magnetic resonance imaging

    DEFF Research Database (Denmark)

    Axelsen, Mette Bjørndal; Ejbjerg, B J; Hetland, M L

    2014-01-01

    OBJECTIVES: To identify the magnetic resonance imaging (MRI) parameter that best differentiates healthy persons and patients with early rheumatoid arthritis (RA), and to investigated responsiveness to treatment of various MRI parameters. METHOD: Conventional MRI and dynamic contrast-enhanced (DCE...

  17. Contrast-enhanced magnetic resonance imaging of tumours of the central nervous systems: a clinical review

    International Nuclear Information System (INIS)

    Graif, M.; Steiner, R.E.

    1986-01-01

    The clinical application of the intravascular paramagnetic contrast agent gadolinium-DTPA for magnetic resonance imaging (MRI) imaging of tumours of the central nervous system (CNS) has been assessed over the past 3 years. Various patterns of contrast enhancement were observed, and situations in MRI where the administration of contrast medium may be useful have been defined. These include lesions which are isointense with normal brain matter, the separation of tumour from surrounding oedema, evaluation of the degree of blood-brain barrier breakdown, delineation of tumours obscured by overlying calcification on computed tomography (CT) and in the investigation of lesions in anatomical areas where CT has known limitations (brain, stem, cervical spine). Changes in relaxation times in normal and abnormal tissues following contrast medium, toxicity and dosage of gadolinium-DTPA, and MRI pulse sequence techniques are reviewed. (author)

  18. Reliability and responsiveness of dynamic contrast-enhanced magnetic resonance imaging in rheumatoid arthritis

    DEFF Research Database (Denmark)

    Axelsen, M.B.; Poggenborg, R.P.; Stoltenberg, M.

    2013-01-01

    intraarticular injection with 80 mg methylprednisolone. Using semi-automated image processing software, DCE-MRI parameters, including the initial rate of enhancement (IRE) and maximal enhancement (ME), were generated for three regions of interest (ROIs): ‘Whole slice’, ‘Quick ROI’, and ‘Precise ROI......Objectives: To investigate the responsiveness to treatment and the reliability of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in rheumatoid arthritis (RA) knee joints. Methods: DCE-MRI was performed in 12 clinically active RA knee joints before and 1, 7, 30, and 180 days after......’. The smallest detectable difference (SDD), the smallest detectable change (SDC), and intra- and inter-reader intraclass correlation coefficients (ICCs) were used to assess the reliability of DCE-MRI. Responsiveness to treatment was assessed by the standardized response mean (SRM). Results: In all patients...

  19. Diagnostic accuracy of contrast-enhanced ultrasound in assessing the therapeutic response to radio frequency ablation for liver tumors: systematic review and meta-analysis.

    Science.gov (United States)

    Xuan, Min; Zhou, Fengsheng; Ding, Yan; Zhu, Qiaoying; Dong, Ji; Zhou, Hao; Cheng, Jun; Jiang, Xiao; Wu, Pengxi

    2018-04-01

    To review the diagnostic accuracy of contrast-enhanced ultrasound (CEUS) used to detect residual or recurrent liver tumors after radiofrequency ablation (RFA). This technique uses contrast-enhanced computer tomography or/and contrast-enhanced magnetic resonance imaging as the gold standard of investigation. MEDLINE, EMBASE, and COCHRANE were systematically searched for all potentially eligible studies comparing CEUS with the reference standard that follows RFA. Risk of bias and applicability concerns were addressed by adopting the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. Pooled point estimates for sensitivity, specificity, positive and negative likelihood ratios, and diagnostic odds ratios (DOR) with 95% CI were computed before plotting the sROC (summary receiver operating characteristic) curve. Meta-regression and subgroup analysis were used to identify the source of the heterogeneity that was detected. Publication bias was evaluated using Deeks' funnel plot asymmetry test. Ten eligible studies on 1162 lesions that occurred between 2001 and 2016 were included in the final analysis. The quality of the included studies assessed by the QUADAS-2 tool was considered reasonable. The pooled sensitivity and specificity of CEUS in detecting residual or recurrent liver tumors had the following values: 0.90 (95% CI 0.85-0.94) and 1.00 (95% CI 0.99-1.00), respectively. Overall DOR was 420.10 (95% CI 142.30-1240.20). The sources of heterogeneity could not be precisely identified by meta-regression or subgroup analysis. No evidence of publication bias was found. This study confirmed that CEUS exhibits high sensitivity and specificity in assessing therapeutic responses to RFA for liver tumors.

  20. Differentiation of benign and malignant solitary pulmonary nodules : value of contrast-enhanced dynamic MR imaging

    International Nuclear Information System (INIS)

    Kim, Jeong Ho; Kim, Hyung Jin; Han, Heon; Lee, Hong Lyeol; Kim, Kwang Ho; Suh, Chang Hae

    1999-01-01

    To evaluate the usefulness of contrast-enhanced dynamic MR imaging for differentiation of benign and malignant solitary pulmonary nodules (SPNs). Twenty-three patients with histologically or radiologically provened SPNs smaller than 40mm (14 benign, 9 malignant) underwent MR examination using the breath-hold fast multiplanar spoiled gradient echo (FMPSPGR) technique. Pre-enhancement MR examination was followed by serial scans obtained at one-minute intervals, beginning one-minute after the onset of bolus injection of paramagnetic contrast agent for a total of five scans. Signal intensities of SPNs were measured from pre- and post-contrast enhanced MR images and peak percentage increase in signal intensity (p%SI) was calculated. Mean percentage increase in signal intensity (m%SI) was also calculated and the time-m%SI curve was plotted. The enhancement patterns of SPNs were classified as homogeneous, peripheral rim-like, inhomogeneous, or no (or minimal) enhancement. We compared differences in p%SI, the pattern of the time-m%SI curve, and the pattern of enhancement between benign and malignant SPNs. On dynamic MR images, alignant SPNs (n=9) showed a significantly higher p%SI than benign SPNs (n=14) (malignant : mean 120.6, range 81.8-171.6; benign : mean 29.5, range 3.7-78.9)(p<0.0001). With 80 p%SI as the threshold for malignancy-positive, both sensitivity and specificity were 100%. The m%SI of malignant SPNs rapidly increased at one minute after enhancement and decreased gradually thereafter, whereas that of benign SPNs increased more slowly to form a plateau. Eighty-nine percent (8/9) of malignant SPNs showed homogeneous enhancement. In contrast, among benign SPNs, peripheral rim-like enhancement and no (or minimal) enhancement occurred in the same proportion of cases : 50%(7/14). The superb demonstration of different enhancement characteristics obtained using dynamic contrast-enhanced MR imaging is useful to discriminate malignant from benign SPNs

  1. Prospective evaluation of contrast-enhanced MR imaging after uncomplicated lumbar discography

    International Nuclear Information System (INIS)

    Carrino, John A.; Swathwood, Todd C.; Morrison, William B.; Glover, J.M.

    2007-01-01

    Postdiscography infection is an uncommon complication. Magnetic resonance (MR) imaging is often the modality of choice for evaluating spinal infection. Discography entails disc access and fluid injection that could alter the baseline MR imaging appearance of the spine and be confounded for infection. Our purpose was to describe the MR imaging findings of the lumbar spine subsequent to uncomplicated discography and to determine if this may mimic infection. In a prospective cohort study of eight adults (age 22-64 years, mean 45 years) with 22 intradiscal injections, all subjects underwent routine unenhanced and contrast-enhanced MR imaging during the 2-3 week interval postdiscography. A subset of four returned for additional MR imaging during the 4-8 week interval postdiscography. MR images were reviewed for intradiscal, endplate, marrow, and epidural findings and then compared with prediscography examinations. Infection was excluded by clinical documentation. Postdiscography MR imaging showed that almost all levels were similar to baseline prediscography examinations. No levels developed new vertebral marrow edema, fluid-like intradiscal signal, endplate irregularity, or epidural abnormality. Two subjects simulated potential discitis, but these findings were unchanged from prediscography and were related to prior surgery. Uncomplicated lumbar spine discography does not cause MR imaging changes that simulate discitis. (orig.)

  2. Chain of evidence generation for contrast enhancement in digital image forensics

    Science.gov (United States)

    Battiato, Sebastiano; Messina, Giuseppe; Strano, Daniela

    2010-01-01

    The quality of the images obtained by digital cameras has improved a lot since digital cameras early days. Unfortunately, it is not unusual in image forensics to find wrongly exposed pictures. This is mainly due to obsolete techniques or old technologies, but also due to backlight conditions. To extrapolate some invisible details a stretching of the image contrast is obviously required. The forensics rules to produce evidences require a complete documentation of the processing steps, enabling the replication of the entire process. The automation of enhancement techniques is thus quite difficult and needs to be carefully documented. This work presents an automatic procedure to find contrast enhancement settings, allowing both image correction and automatic scripting generation. The technique is based on a preprocessing step which extracts the features of the image and selects correction parameters. The parameters are thus saved through a JavaScript code that is used in the second step of the approach to correct the image. The generated script is Adobe Photoshop compliant (which is largely used in image forensics analysis) thus permitting the replication of the enhancement steps. Experiments on a dataset of images are also reported showing the effectiveness of the proposed methodology.

  3. Prospective evaluation of contrast-enhanced MR imaging after uncomplicated lumbar discography

    Energy Technology Data Exchange (ETDEWEB)

    Carrino, John A. [Johns Hopkins University School of Medicine, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Outpatient Center, Baltimore, MD (United States); Swathwood, Todd C. [Blue Ridge Orthopedic Associates, Seneca (United States); Morrison, William B. [Thomas Jefferson University Hospital, Department of Radiology, Philadelphia, PA (United States); Glover, J.M. [Northern Arizona Orthopaedics, Flagstaff, AZ (United States)

    2007-04-15

    Postdiscography infection is an uncommon complication. Magnetic resonance (MR) imaging is often the modality of choice for evaluating spinal infection. Discography entails disc access and fluid injection that could alter the baseline MR imaging appearance of the spine and be confounded for infection. Our purpose was to describe the MR imaging findings of the lumbar spine subsequent to uncomplicated discography and to determine if this may mimic infection. In a prospective cohort study of eight adults (age 22-64 years, mean 45 years) with 22 intradiscal injections, all subjects underwent routine unenhanced and contrast-enhanced MR imaging during the 2-3 week interval postdiscography. A subset of four returned for additional MR imaging during the 4-8 week interval postdiscography. MR images were reviewed for intradiscal, endplate, marrow, and epidural findings and then compared with prediscography examinations. Infection was excluded by clinical documentation. Postdiscography MR imaging showed that almost all levels were similar to baseline prediscography examinations. No levels developed new vertebral marrow edema, fluid-like intradiscal signal, endplate irregularity, or epidural abnormality. Two subjects simulated potential discitis, but these findings were unchanged from prediscography and were related to prior surgery. Uncomplicated lumbar spine discography does not cause MR imaging changes that simulate discitis. (orig.)

  4. Validation of dynamic contrast-enhanced ultrasound in predicting outcomes of antiangiogenic therapy for solid tumors: the French multicenter support for innovative and expensive techniques study.

    Science.gov (United States)

    Lassau, Nathalie; Bonastre, Julia; Kind, Michèle; Vilgrain, Valérie; Lacroix, Joëlle; Cuinet, Marie; Taieb, Sophie; Aziza, Richard; Sarran, Antony; Labbe-Devilliers, Catherine; Gallix, Benoit; Lucidarme, Olivier; Ptak, Yvette; Rocher, Laurence; Caquot, Louis-Michel; Chagnon, Sophie; Marion, Denis; Luciani, Alain; Feutray, Sylvaine; Uzan-Augui, Joëlle; Coiffier, Benedicte; Benastou, Baya; Koscielny, Serge

    2014-12-01

    Dynamic contrast-enhanced ultrasound (DCE-US) has been used in single-center studies to evaluate tumor response to antiangiogenic treatments: the change of area under the perfusion curve (AUC), a criterion linked to blood volume, was consistently correlated with the Response Evaluation Criteria in Solid Tumors response. The main objective here was to do a multicentric validation of the use of DCE-US to evaluate tumor response in different solid tumor types treated by several antiangiogenic agents. A secondary objective was to evaluate the costs of the procedure. This prospective study included patients from 2007 to 2010 in 19 centers (8 teaching hospitals and 11 comprehensive cancer centers). All patients treated with antiangiogenic therapy were eligible. Dynamic contrast-enhanced ultrasound examinations were performed at baseline as well as on days 7, 15, 30, and 60. For each examination, a perfusion curve was recorded during 3 minutes after injection of a contrast agent. Change from baseline at each time point was estimated for each of 7 fitted criteria. The main end point was freedom from progression (FFP). Criterion/time-point combinations with the strongest correlation with FFP were analyzed further to estimate an optimal cutoff point. A total of 1968 DCE-US examinations in 539 patients were analyzed. The median follow-up was 1.65 years. Variations from baseline were significant at day 30 for several criteria, with AUC having the most significant association with FFP (P = 0.00002). Patients with a greater than 40% decrease in AUC at day 30 had better FFP (P = 0.005) and overall survival (P = 0.05). The mean cost of each DCE-US was 180&OV0556;, which corresponds to $250 using the current exchange rate. Dynamic contrast-enhanced ultrasound is a new functional imaging technique that provides a validated criterion, namely, the change of AUC from baseline to day 30, which is predictive of tumor progression in a large multicenter cohort. Because of its low cost, it

  5. Quantitative contrast enhanced ultrasound of the liver for time intensity curves-Reliability and potential sources of errors.

    Science.gov (United States)

    Ignee, Andre; Jedrejczyk, Maciej; Schuessler, Gudrun; Jakubowski, Wieslaw; Dietrich, Christoph F

    2010-01-01

    Time intensity curves for real-time contrast enhanced low MI ultrasound is a promising technique since it adds objective data to the more subjective conventional contrast enhanced technique. Current developments showed that the amount of uptake in modern targeted therapy strategies correlates with therapy response. Nevertheless no basic research has been done concerning the reliability and validity of the method. Videos sequences of 31 consecutive patients for at least 60s were recorded. Parameters analysed: area under the curve, maximum intensity, mean transit time, perfusion index, time to peak, rise time. The influence of depth, lateral shift as well as size and shape of the region of interest was analysed. The parameters time to peak and rise time showed a good stability in different depths. Overall there was a variation >50% for all other parameters. Mean transit time, time to peak and rise time were stable from 3 to 10cm depths, whereas all other parameters showed only satisfying results at 4-6cm. Time to peak and rise time were stable as well against lateral shifting whereas all other parameters had again variations over 50%. Size and shape of the region of interest did not influence the results. (1) It is important to compare regions of interest, e.g. in a tumour vs. representative parenchyma in the same depths. (2) Time intensity curves should not be analysed in a depth of less than 4cm. (3) The parameters area under the curve, perfusion index and maximum intensity should not be analysed in a depth more than 6cm. (4) Size and shape of a region of interest in liver parenchyma do not affect time intensity curves. Copyright (c) 2009 Elsevier Ireland Ltd. All rights reserved.

  6. Quantitative contrast enhanced ultrasound of the liver for time intensity curves-Reliability and potential sources of errors

    Energy Technology Data Exchange (ETDEWEB)

    Ignee, Andre [Department of Internal Medicine and Diagnostic Imaging, Caritas Hospital, Uhlandstr. 7, 97990 Bad Mergentheim (Germany)], E-mail: andre.ignee@gmx.de; Jedrejczyk, Maciej [Department of Diagnostic Imaging, 2nd Division of Medical Faculty, Medical University, Ul. Kondratowicza 8, 03-242 Warsaw (Poland)], E-mail: mjedrzejczyk@interia.pl; Schuessler, Gudrun [Department of Internal Medicine and Diagnostic Imaging, Caritas Hospital, Uhlandstr. 7, 97990 Bad Mergentheim (Germany)], E-mail: gudrunschuessler@gmx.de; Jakubowski, Wieslaw [Department of Diagnostic Imaging, 2nd Division of Medical Faculty, Medical University, Ul. Kondratowicza 8, 03-242 Warsaw (Poland)], E-mail: ewajbmd@go2.pl; Dietrich, Christoph F. [Department of Internal Medicine and Diagnostic Imaging, Caritas Hospital, Uhlandstr. 7, 97990 Bad Mergentheim (Germany)], E-mail: christoph.dietrich@ckbm.de

    2010-01-15

    Introduction: Time intensity curves for real-time contrast enhanced low MI ultrasound is a promising technique since it adds objective data to the more subjective conventional contrast enhanced technique. Current developments showed that the amount of uptake in modern targeted therapy strategies correlates with therapy response. Nevertheless no basic research has been done concerning the reliability and validity of the method. Patients and methods: Videos sequences of 31 consecutive patients for at least 60 s were recorded. Parameters analysed: area under the curve, maximum intensity, mean transit time, perfusion index, time to peak, rise time. The influence of depth, lateral shift as well as size and shape of the region of interest was analysed. Results: The parameters time to peak and rise time showed a good stability in different depths. Overall there was a variation >50% for all other parameters. Mean transit time, time to peak and rise time were stable from 3 to 10 cm depths, whereas all other parameters showed only satisfying results at 4-6 cm. Time to peak and rise time were stable as well against lateral shifting whereas all other parameters had again variations over 50%. Size and shape of the region of interest did not influence the results. Discussion: (1) It is important to compare regions of interest, e.g. in a tumour vs. representative parenchyma in the same depths. (2) Time intensity curves should not be analysed in a depth of less than 4 cm. (3) The parameters area under the curve, perfusion index and maximum intensity should not be analysed in a depth more than 6 cm. (4) Size and shape of a region of interest in liver parenchyma do not affect time intensity curves.

  7. Quantitative contrast enhanced ultrasound of the liver for time intensity curves-Reliability and potential sources of errors

    International Nuclear Information System (INIS)

    Ignee, Andre; Jedrejczyk, Maciej; Schuessler, Gudrun; Jakubowski, Wieslaw; Dietrich, Christoph F.

    2010-01-01

    Introduction: Time intensity curves for real-time contrast enhanced low MI ultrasound is a promising technique since it adds objective data to the more subjective conventional contrast enhanced technique. Current developments showed that the amount of uptake in modern targeted therapy strategies correlates with therapy response. Nevertheless no basic research has been done concerning the reliability and validity of the method. Patients and methods: Videos sequences of 31 consecutive patients for at least 60 s were recorded. Parameters analysed: area under the curve, maximum intensity, mean transit time, perfusion index, time to peak, rise time. The influence of depth, lateral shift as well as size and shape of the region of interest was analysed. Results: The parameters time to peak and rise time showed a good stability in different depths. Overall there was a variation >50% for all other parameters. Mean transit time, time to peak and rise time were stable from 3 to 10 cm depths, whereas all other parameters showed only satisfying results at 4-6 cm. Time to peak and rise time were stable as well against lateral shifting whereas all other parameters had again variations over 50%. Size and shape of the region of interest did not influence the results. Discussion: (1) It is important to compare regions of interest, e.g. in a tumour vs. representative parenchyma in the same depths. (2) Time intensity curves should not be analysed in a depth of less than 4 cm. (3) The parameters area under the curve, perfusion index and maximum intensity should not be analysed in a depth more than 6 cm. (4) Size and shape of a region of interest in liver parenchyma do not affect time intensity curves.

  8. Quantitative analysis of thyroid tumors vascularity: A comparison between 3-D contrast-enhanced ultrasound and 3-D Power Doppler on benign and malignant thyroid nodules.

    Science.gov (United States)

    Caresio, Cristina; Caballo, Marco; Deandrea, Maurilio; Garberoglio, Roberto; Mormile, Alberto; Rossetto, Ruth; Limone, Paolo; Molinari, Filippo

    2018-05-15

    To perform a comparative quantitative analysis of Power Doppler ultrasound (PDUS) and Contrast-Enhancement ultrasound (CEUS) for the quantification of thyroid nodules vascularity patterns, with the goal of identifying biomarkers correlated with the malignancy of the nodule with both imaging techniques. We propose a novel method to reconstruct the vascular architecture from 3-D PDUS and CEUS images of thyroid nodules, and to automatically extract seven quantitative features related to the morphology and distribution of vascular network. Features include three tortuosity metrics, the number of vascular trees and branches, the vascular volume density, and the main spatial vascularity pattern. Feature extraction was performed on 20 thyroid lesions (ten benign and ten malignant), of which we acquired both PDUS and CEUS. MANOVA (multivariate analysis of variance) was used to differentiate benign and malignant lesions based on the most significant features. The analysis of the extracted features showed a significant difference between the benign and malignant nodules for both PDUS and CEUS techniques for all the features. Furthermore, by using a linear classifier on the significant features identified by the MANOVA, benign nodules could be entirely separated from the malignant ones. Our early results confirm the correlation between the morphology and distribution of blood vessels and the malignancy of the lesion, and also show (at least for the dataset used in this study) a considerable similarity in terms of findings of PDUS and CEUS imaging for thyroid nodules diagnosis and classification. © 2018 American Association of Physicists in Medicine.

  9. Extraction of Lesion-Partitioned Features and Retrieval of Contrast-Enhanced Liver Images

    Directory of Open Access Journals (Sweden)

    Mei Yu

    2012-01-01

    Full Text Available The most critical step in grayscale medical image retrieval systems is feature extraction. Understanding the interrelatedness between the characteristics of lesion images and corresponding imaging features is crucial for image training, as well as for features extraction. A feature-extraction algorithm is developed based on different imaging properties of lesions and on the discrepancy in density between the lesions and their surrounding normal liver tissues in triple-phase contrast-enhanced computed tomographic (CT scans. The algorithm includes mainly two processes: (1 distance transformation, which is used to divide the lesion into distinct regions and represents the spatial structure distribution and (2 representation using bag of visual words (BoW based on regions. The evaluation of this system based on the proposed feature extraction algorithm shows excellent retrieval results for three types of liver lesions visible on triple-phase scans CT images. The results of the proposed feature extraction algorithm show that although single-phase scans achieve the average precision of 81.9%, 80.8%, and 70.2%, dual- and triple-phase scans achieve 86.3% and 88.0%.

  10. Clinical use of gadobutrol for contrast-enhanced magnetic resonance imaging of neurological diseases

    Directory of Open Access Journals (Sweden)

    Cheng KT

    2012-02-01

    Full Text Available Kenneth T Cheng1, Hannah Y Cheng2, Kam Leung31Department of Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, MD, USA; 2Freelance Technical Writer, New Orleans, LA, USA; 3National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, USAAbstract: Contrast-enhanced magnetic resonance imaging (CE-MRI is an important clinical tool for diagnosing neurological diseases. The appropriate use of a suitable MRI contrast agent or contrast pharmaceutical is essential for CE-MRI to produce desirable diagnostic images. Currently, there are seven contrast agents (CAs or pharmaceuticals approved for clinical imaging of the central nervous system (CNS in the US, Europe, or Japan. All of the clinically approved CAs are water-soluble gadolinium-based contrast agents (GBCAs which do not penetrate the CNS blood–brain barrier (BBB. These agents are used for imaging CNS areas without a BBB, or various pathologies, such as tumors and infection that break down the BBB and allow CAs to enter into the surrounding parenchyma. Clinically, GBCAs are most useful for detecting primary and secondary cerebral neoplastic lesions. Among these CNS GBCAs, gadobutrol (Gd-BT-DO3A, Gadovist™ is a neutral, nonionic, macrocyclic compound that showed promising results from clinical trials of CNS imaging. In comparison with other GBCAs, Gd-BT-DO3A has relatively high in vitro kinetic stability and r1 relaxivity. Gd-BT-DO3A has been recently approved by the US Food and Drug Administration (FDA in 2011 for CNS imaging. A review of available literature shows that Gd-BT-DO3A exhibits similar safety and clinical efficacy profiles to other GBCAs. Gd-BT-DO3A has the distinguishing feature that it is the only clinical agent commercially available in a formulation of 1.0 M concentration with a relatively higher in vitro T1 shortening per unit volume than other clinical GBCAs which are only

  11. Characterisation of focal liver lesions with unenhanced and contrast enhanced low MI real time ultrasound: On-site unblinded versus off-site blinded reading

    International Nuclear Information System (INIS)

    Hohmann, Joachim; Skrok, Jan; Basilico, Raffaella; Jennett, Manfred; Müller, Anja; Wolf, Karl-Jürgen; Albrecht, Thomas

    2012-01-01

    Objective: To compare on-site and blinded off-site reading of baseline ultrasound (US) and contrast enhanced ultrasound (CEUS) for classification and characterisation of focal liver lesions. Materials and methods: 99 patients (57 women and 42 men, age range 18–89 years, mean age: 59 years) with 53 malignant and 46 benign liver lesions were studied with unenhanced US followed by contrast enhanced US after injection of 2.4 ml SonoVue ® (Bracco, Milano, Italy). Image interpretation was performed on-site with clinical information available by consensus of two readers and off-site by two independent blinded readers at two different centers. Comparison of pre and post contrast scans and of the different readers was performed. Reference examinations were histology, intraoperative US, MRI or CT. Results: Sensitivity for malignancy improved from 81/89/66% (on-site/off-site reader 1/2) before to 100/96/96% post contrast administration (p < 0.05, except for reader 1). Specificity improved from 48/48/54% on baseline US to 89/80/76% on CEUS (p < 0.05). Accuracy for specific lesion diagnosis was 62/59/50% pre and 90/77/72% post contrast (p < 0.05). Classification and characterisation post contrast were mildly inferior for off-site reading. Agreement between on-site and off-site readers of unenhanced scans was fair (κ = 0.29–0.39) while it was good for CEUS (κ = 0.63–0.79). Conclusions: CEUS improves classification and characterisation of focal liver lesions and interobserver agreement compared to conventional US. Classification and characterisation post contrast were mildly but statistically significantly better for on-site than for off-site reading.

  12. Detection of acute avascular necrosis with dynamic contrast-enhanced MR imaging

    International Nuclear Information System (INIS)

    Nadel, S.N.; Richardson, W.J.; Martinez, S.; Rizk, W.S.; Malizos, K.; Debatin, J.F.

    1991-01-01

    Early detection of avascular necrosis (AVN) may allow earlier intervention and lead to improved treatment success. This paper is designed to compare standard and dynamic contrast-enhanced MR imaging in the detection of acute AVN. A previously described animal model of AVN was used. Five anesthetized dogs underwent right femoral head devascularization, including placement of a supercooling coil around the femoral neck. Within 3 hours the dogs were imaged in a 1.5-T Signa magnet. Standard T1-weighted, T2-weighted, and STIR images were obtained through both hips. A DiGrass sequence with 30 sequential 3.2-second T1-weighted images was used, and 0.2 mmol/kg gadoteridol was injected intravenously at the start of the sequence at 2 mL/sec with an automated injector. Following imaging, oxytetracycline was given intravenously. After 3 days the dogs were killed, and their femoral heads were extracted, coronally sectioned, and analyzed for fluorescence. T1-weighted, T2-weighted, and STIR sequences showed no marrow abnormalities on either the normal or the operated-on side. With contrast material injection, all normal areas and the unoperated portion the femoral neck and diaphysis enhanced markedly 4-9 seconds following the bolus

  13. Local contrast-enhanced MR images via high dynamic range processing.

    Science.gov (United States)

    Chandra, Shekhar S; Engstrom, Craig; Fripp, Jurgen; Neubert, Ales; Jin, Jin; Walker, Duncan; Salvado, Olivier; Ho, Charles; Crozier, Stuart

    2018-09-01

    To develop a local contrast-enhancing and feature-preserving high dynamic range (HDR) image processing algorithm for multichannel and multisequence MR images of multiple body regions and tissues, and to evaluate its performance for structure visualization, bias field (correction) mitigation, and automated tissue segmentation. A multiscale-shape and detail-enhancement HDR-MRI algorithm is applied to data sets of multichannel and multisequence MR images of the brain, knee, breast, and hip. In multisequence 3T hip images, agreement between automatic cartilage segmentations and corresponding synthesized HDR-MRI series were computed for mean voxel overlap established from manual segmentations for a series of cases. Qualitative comparisons between the developed HDR-MRI and standard synthesis methods were performed on multichannel 7T brain and knee data, and multisequence 3T breast and knee data. The synthesized HDR-MRI series provided excellent enhancement of fine-scale structure from multiple scales and contrasts, while substantially reducing bias field effects in 7T brain gradient echo, T 1 and T 2 breast images and 7T knee multichannel images. Evaluation of the HDR-MRI approach on 3T hip multisequence images showed superior outcomes for automatic cartilage segmentations with respect to manual segmentation, particularly around regions with hyperintense synovial fluid, across a set of 3D sequences. The successful combination of multichannel/sequence MR images into a single-fused HDR-MR image format provided consolidated visualization of tissues within 1 omnibus image, enhanced definition of thin, complex anatomical structures in the presence of variable or hyperintense signals, and improved tissue (cartilage) segmentation outcomes. © 2018 International Society for Magnetic Resonance in Medicine.

  14. General Ultrasound Imaging

    Medline Plus

    Full Text Available ... those sound waves to create an image. Ultrasound examinations do not use ionizing radiation (as used in ... ultrasound study may be part of an ultrasound examination. Doppler ultrasound , also called color Doppler ultrasonography, is ...

  15. Importance of contrast-enhanced fluid-attenuated inversion reconvery magnetic resonance imaging in various intracranial pathologic conditions

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eun Kyoung; Lee, Eun Ja; Kim, Sung Won; Lee, Yong Seok [Dept. of Radiology, Dongguk University Ilsan Hospital, Goyang(Korea, Republic of)

    2016-02-15

    Intracranial lesions may show contrast enhancement through various mechanisms that are closely associated with the disease process. The preferred magnetic resonance sequence in contrast imaging is T1-weighted imaging (T1WI) at most institutions. However, lesion enhancement is occasionally inconspicuous on T1WI. Although fluid-attenuated inversion recovery (FLAIR) sequences are commonly considered as T2-weighted imaging with dark cerebrospinal fluid, they also show mild T1-weighted contrast, which is responsible for the contrast enhancement. For several years, FLAIR imaging has been successfully incorporated as a routine sequence at our institution for contrast-enhanced (CE) brain imaging in detecting various intracranial diseases. In this pictorial essay, we describe and illustrate the diagnostic importance of CE-FLAIR imaging in various intracranial pathologic conditions.

  16. Assessment of contrast enhanced respiration managed cone-beam CT for image guided radiotherapy of intrahepatic tumors

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, Nikolaj K. G., E-mail: nkyj@regionsjaelland.dk [Physics and Engineering, London Regional Cancer Program, London, Ontario N6A3K7 (Canada); Stewart, Errol [Radiology, St. Joseph' s Health Care, London, Ontario N6A 4V2 (Canada); Imaging Research Lab, Robarts Research Institute, London, Ontario N6A 5B7 (Canada); Imaging Program, Lawson Health Research Institute, London, Ontario N6C 2R5 (Canada); Lock, Michael; Fisher, Barbara [Radiation Oncology, London Regional Cancer Program, London, Ontario N6A3K7 (Canada); Department of Oncology, University of Western Ontario, London, Ontario N6A 4L6 (Canada); Kozak, Roman [Radiology, St. Joseph' s Health Care, London, Ontario N6A 4V2 (Canada); Chen, Jeff [Physics and Engineering, London Regional Cancer Program, London, Ontario N6A3K7 (Canada); Department of Oncology, University of Western Ontario, London, Ontario N6A 4L6 (Canada); Department of Medical Biophysics, University of Western Ontario, London, Ontario N6A 5C1 (Canada); Lee, Ting-Yim [Radiology, St. Joseph' s Health Care, London, Ontario N6A 4V2 (Canada); Imaging Research Lab, Robarts Research Institute, London, Ontario N6A 5B7 (Canada); Imaging Program, Lawson Health Research Institute, London, Ontario N6C 2R5 (Canada); Department of Oncology, University of Western Ontario, London, Ontario N6A 4L6 (Canada); Department of Medical Biophysics, University of Western Ontario, London, Ontario N6A 5C1 (Canada); Wong, Eugene [Physics and Engineering, London Regional Cancer Program, London, Ontario N6A3K7 (Canada); Department of Oncology, University of Western Ontario, London, Ontario N6A 4L6 (Canada); Department of Medical Biophysics, University of Western Ontario, London, Ontario N6A 5C1 (Canada); Department of Physics and Astronomy, University of Western Ontario, London, Ontario N6A 3K7 (Canada)

    2014-05-15

    Purpose: Contrast enhancement and respiration management are widely used during image acquisition for radiotherapy treatment planning of liver tumors along with respiration management at the treatment unit. However, neither respiration management nor intravenous contrast is commonly used during cone-beam CT (CBCT) image acquisition for alignment prior to radiotherapy. In this study, the authors investigate the potential gains of injecting an iodinated contrast agent in combination with respiration management during CBCT acquisition for liver tumor radiotherapy. Methods: Five rabbits with implanted liver tumors were subjected to CBCT with and without motion management and contrast injection. The acquired CBCT images were registered to the planning CT to determine alignment accuracy and dosimetric impact. The authors developed a simulation tool for simulating contrast-enhanced CBCT images from dynamic contrast enhanced CT imaging (DCE-CT) to determine optimal contrast injection protocols. The tool was validated against contrast-enhanced CBCT of the rabbit subjects and was used for five human patients diagnosed with hepatocellular carcinoma. Results: In the rabbit experiment, when neither motion management nor contrast was used, tumor centroid misalignment between planning image and CBCT was 9.2 mm. This was reduced to 2.8 mm when both techniques were employed. Tumors were not visualized in clinical CBCT images of human subjects. Simulated contrast-enhanced CBCT was found to improve tumor contrast in all subjects. Different patients were found to require different contrast injections to maximize tumor contrast. Conclusions: Based on the authors’ animal study, respiration managed contrast enhanced CBCT improves IGRT significantly. Contrast enhanced CBCT benefits from patient specific tracer kinetics determined from DCE-CT.

  17. Assessment of contrast enhanced respiration managed cone-beam CT for image guided radiotherapy of intrahepatic tumors

    International Nuclear Information System (INIS)

    Jensen, Nikolaj K. G.; Stewart, Errol; Lock, Michael; Fisher, Barbara; Kozak, Roman; Chen, Jeff; Lee, Ting-Yim; Wong, Eugene

    2014-01-01

    Purpose: Contrast enhancement and respiration management are widely used during image acquisition for radiotherapy treatment planning of liver tumors along with respiration management at the treatment unit. However, neither respiration management nor intravenous contrast is commonly used during cone-beam CT (CBCT) image acquisition for alignment prior to radiotherapy. In this study, the authors investigate the potential gains of injecting an iodinated contrast agent in combination with respiration management during CBCT acquisition for liver tumor radiotherapy. Methods: Five rabbits with implanted liver tumors were subjected to CBCT with and without motion management and contrast injection. The acquired CBCT images were registered to the planning CT to determine alignment accuracy and dosimetric impact. The authors developed a simulation tool for simulating contrast-enhanced CBCT images from dynamic contrast enhanced CT imaging (DCE-CT) to determine optimal contrast injection protocols. The tool was validated against contrast-enhanced CBCT of the rabbit subjects and was used for five human patients diagnosed with hepatocellular carcinoma. Results: In the rabbit experiment, when neither motion management nor contrast was used, tumor centroid misalignment between planning image and CBCT was 9.2 mm. This was reduced to 2.8 mm when both techniques were employed. Tumors were not visualized in clinical CBCT images of human subjects. Simulated contrast-enhanced CBCT was found to improve tumor contrast in all subjects. Different patients were found to require different contrast injections to maximize tumor contrast. Conclusions: Based on the authors’ animal study, respiration managed contrast enhanced CBCT improves IGRT significantly. Contrast enhanced CBCT benefits from patient specific tracer kinetics determined from DCE-CT

  18. General Ultrasound Imaging

    Medline Plus

    Full Text Available ... through blood vessels. Ultrasound imaging is a noninvasive medical test that helps physicians diagnose and treat medical conditions. Conventional ultrasound displays the images in thin, ...

  19. Demonstration of evolution of hemispherical spondysclerosis by contrast enhanced Gd-DTPA magnetic resonance imaging

    International Nuclear Information System (INIS)

    Jevtic, V.; Majcen, N.

    2004-01-01

    Background. The purpose of the study was to estimate the value of Gd-DTPA magnetic resonance imaging (MRI) in demonstrating the evolution of hemispherical spondylosclerosis (HSS). Patients and methods. In eighteen patients with chronic low back pain and typical radiographic findings of HSS seen on plain films, Gd-DTPA MRI of the lumbar spine was performed. MRI morphological and signal intensity appearances of HSS were analysed and compared with radiographic changes. Results. On the basis of MRI features, three distinct groups of cases were identifiable. Within the first group the region of dome-shaped osteosclerosis demonstrated low signal intensity on T1-weighted precontrast spin-echo images, high signal intensity on T2-weighted images and diffuse contrast enhancement on T1-weighted postcontrast images, findings compatible with bone marrow oedema and hyperaemia. The second group showed high signal intensity vertebral body corners surrounded by low signal intensity area, which indicated the combination of fat accumulation and the sclerotic bone. In the third intermediate group anterior disco-vertebral junctions revealed a mixture of MRI appearances characteristic of the first and the second group. Conclusions. Gd-DTPA MRI is capable of demonstrating a spectrum of features which reflect the evolution of HSS. These typical appearances showed by MRI could be of eventual clinical relevance in following the progression of HSS. (author)

  20. Generalized image contrast enhancement technique based on the Heinemann contrast discrimination model

    Science.gov (United States)

    Liu, Hong; Nodine, Calvin F.

    1996-07-01

    This paper presents a generalized image contrast enhancement technique, which equalizes the perceived brightness distribution based on the Heinemann contrast discrimination model. It is based on the mathematically proven existence of a unique solution to a nonlinear equation, and is formulated with easily tunable parameters. The model uses a two-step log-log representation of luminance contrast between targets and surround in a luminous background setting. The algorithm consists of two nonlinear gray scale mapping functions that have seven parameters, two of which are adjustable Heinemann constants. Another parameter is the background gray level. The remaining four parameters are nonlinear functions of the gray-level distribution of the given image, and can be uniquely determined once the previous three are set. Tests have been carried out to demonstrate the effectiveness of the algorithm for increasing the overall contrast of radiology images. The traditional histogram equalization can be reinterpreted as an image enhancement technique based on the knowledge of human contrast perception. In fact, it is a special case of the proposed algorithm.

  1. Dynamic contrast-enhanced ultrasound and transient arterial occlusion for quantification of arterial perfusion reserve in peripheral arterial disease

    International Nuclear Information System (INIS)

    Amarteifio, E.; Wormsbecher, S.; Krix, M.; Demirel, S.; Braun, S.; Delorme, S.; Böckler, D.; Kauczor, H.-U.; Weber, M.-A.

    2012-01-01

    Objective: To quantify muscular micro-perfusion and arterial perfusion reserve in peripheral arterial disease (PAD) with dynamic contrast-enhanced ultrasound (CEUS) and transient arterial occlusion. Materials and methods: This study had local institutional review board approval and written informed consent was obtained from all subjects. We examined the dominant lower leg of 40 PAD Fontaine stage IIb patients (mean age, 65 years) and 40 healthy volunteers (mean age, 54 years) with CEUS (7 MHz; MI, 0.28) during continuous intravenous infusion of 4.8 mL microbubbles. Transient arterial occlusion at mid-thigh level simulated physical exercise. With time–CEUS–intensity curves obtained from regions of interest within calf muscles, we derived the maximum CEUS signal after occlusion (max) and its time (t max ), slope to maximum (m), vascular response after occlusion (AUC post ), and analysed accuracy, receiver operating characteristic (ROC) curves, and correlations with ankle-brachial index (ABI) and walking distance. Results: All parameters differed in PAD and volunteers (p max was delayed (31.2 ± 13.6 vs. 16.7 ± 8.5 s, p post as optimal parameter combination for diagnosing PAD and therefore impaired arterial perfusion reserve. Conclusions: Dynamic CEUS with transient arterial occlusion quantifies muscular micro-perfusion and arterial perfusion reserve. The technique is accurate to diagnose PAD.

  2. Assessment of skeletal muscle microcirculation in type 2 diabetes mellitus using dynamic contrast-enhanced ultrasound: a pilot study.

    Science.gov (United States)

    Amarteifio, Erick; Wormsbecher, Stephanie; Demirel, Serdar; Krix, Martin; Braun, Simone; Rehnitz, Christoph; Delorme, Stefan; Kauczor, Hans-Ulrich; Weber, Marc-André

    2013-09-01

    To investigate muscular micro-perfusion by employing dynamic contrast-enhanced ultrasound (CEUS) and performing transient arterial occlusion in patients with type 2 diabetes mellitus (DM-2). Twenty DM-2 patients (mean age, 58 ± 8.6 years; duration of diabetes, 15.4 ± 12.1 years) and 20 healthy volunteers (mean age, 54 ± 5.4 years) participated. CEUS was applied to the calf, while 4.8 mL of SonoVue(®) was injected intravenously. At the thigh level, arterial occlusion (60 s) was performed. CEUS parameters (tmax, max, AUCpost and m) were evaluated and Pearson-product-moment correlation coefficients were computed. A moderate negative correlation of HbA1c and max was established (-0.53). Max in patients with DM-2 >10 years was 79.89 ± 37.4. Max in patients with DM-2 duration 10 years was 3924.01 ± 1630.52. AUCpost in patients with DM-2 duration <10 years was 6453.59 ± 3206.23 (p = 0.04). Patients with long history of DM-2 present with impaired muscular perfusion. CEUS and transient arterial occlusion may provide appropriate methods for semi-quantitative evaluation of muscular micro-perfusion in patients with DM-2.

  3. Contrast-Enhanced Ultrasound in the Diagnosis of Hepatocellular Carcinoma and Intrahepatic Cholangiocarcinoma: Controversy over the ASSLD Guideline

    Directory of Open Access Journals (Sweden)

    Le-Hang Guo

    2015-01-01

    Full Text Available Hepatocellular carcinoma (HCC and intrahepatic cholangiocarcinoma (ICC are both regarded as primary liver cancers, having different biological behaviors and prognoses. Correct differentiation between them is essential for surgical planning and prognosis assessment. In 2005, the American Association for the Study of Liver Diseases (AASLD recommended that noninvasive diagnosis of HCC is achievable by a single dynamic technique (including contrast-enhanced ultrasound (CEUS showing intense arterial uptake followed by washout of contrast in the venous-delayed phases. However, CEUS has been dropped from the diagnostic techniques in the latest AASLD guideline according to the opinion of some authors from Europe that CEUS may offer false positive HCC diagnosis in patients with ICC. Since the update of AASLD guideline has been released, increased attention has been paid to this interesting topic. Remarkable controversy over this issue is present and this removal was not well received in Europe and Asia. This commentary summarized the opinions for the role of CUES in differentiation between HCC and ICC in recent years. It is concluded that prospective studies with strict design and large case series are mandatory to solve the controversies and stratification of ICC in terms of tumor size and liver background is also essential.

  4. Value of contrast-enhanced sonographic micro flow imaging for prostate cancer detection with t-PSA level of 4–10 ng/mL

    International Nuclear Information System (INIS)

    Guo, Yi-Fen; Li, Feng-Hua; Xie, Shao-Wei; Xia, Jian-Guo; Fang, Hua; Li, Hong-Li

    2012-01-01

    Objectives: To compare the efficiency of contrast-enhanced ultrasonographic micro flow imaging (MFI) with conventional transrectal ultrasound (TRUS) in detecting prostate cancer with serum total prostate-specific antigen (t-PSA) of 4.0–10.0 ng/mL. To evaluate the value of contrast-enhanced ultrasonographic MFI in detecting prostate cancer with t-PSA in diagnostic gray zone. Methods: 47 patients with t-PSA 4.0–10.0 ng/mL underwent gray scale, power Doppler TRUS and MFI examinations before ultrasound guided biopsies. Biopsies were performed at twelve sites in the base, the mid-gland and the apex of the prostate in each patient, when there was no abnormal ultrasound finding. When an abnormality was present at MFI, the biopsy specimen from the corresponding site was directed toward the abnormal finding. With histological results of prostate biopsy as reference standards, we assessed the cancer detection of these three methods. Results: 564 specimens were collected in this study, in which 101 were prostate cancer confirmed histologically. 152 of 564 specimens were demonstrated abnormal on MFI images, in which 71 were malignant and 81 were benign confirmed histologically. The sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) for MFI in detecting prostate caner were 70.3%, 82.5%, 80.3%, 46.7% and 92.7%, respectively. The sensitivity and NPV for MFI were significantly better than gray scale (38.6%, 86.9%) and power Doppler (32.7%, 86.0%) (P < 0.001) TRUS. Conclusions: Contrast-enhanced ultrasonographic MFI could significantly improve the detection rate of prostate cancer with t-PSA in diagnostic gray zone (4–10 ng/mL) than conventional ultrasound.

  5. Contrast-enhanced magnetic resonance angiography in carotid artery disease: does automated image registration improve image quality?

    International Nuclear Information System (INIS)

    Menke, Jan; Larsen, Joerg

    2009-01-01

    Contrast-enhanced magnetic resonance angiography (MRA) is a noninvasive imaging alternative to digital subtraction angiography (DSA) for patients with carotid artery disease. In DSA, image quality can be improved by shifting the mask image if the patient has moved during angiography. This study investigated whether such image registration may also help to improve the image quality of carotid MRA. Data from 370 carotid MRA examinations of patients likely to have carotid artery disease were prospectively collected. The standard nonregistered MRAs were compared to automatically linear, affine and warp registered MRA by using three image quality parameters: the vessel detection probability (VDP) in maximum intensity projection (MIP) images, contrast-to-noise ratio (CNR) in MIP images, and contrast-to-noise ratio in three-dimensional image volumes. A body shift of less than 1 mm occurred in 96.2% of cases. Analysis of variance revealed no significant influence of image registration and body shift on image quality (p > 0.05). In conclusion, standard contrast-enhanced carotid MRA usually requires no image registration to improve image quality and is generally robust against any naturally occurring body shift. (orig.)

  6. Ultra-high field upper extremity peripheral nerve and non-contrast enhanced vascular imaging.

    Directory of Open Access Journals (Sweden)

    Shailesh B Raval

    Full Text Available The purpose of this study was to explore the efficacy of Ultra-high field [UHF] 7 Tesla [T] MRI as compared to 3T MRI in non-contrast enhanced [nCE] imaging of structural anatomy in the elbow, forearm, and hand [upper extremity].A wide range of sequences including T1 weighted [T1] volumetric interpolate breath-hold exam [VIBE], T2 weighted [T2] double-echo steady state [DESS], susceptibility weighted imaging [SWI], time-of-flight [TOF], diffusion tensor imaging [DTI], and diffusion spectrum imaging [DSI] were optimized and incorporated with a radiofrequency [RF] coil system composed of a transverse electromagnetic [TEM] transmit coil combined with an 8-channel receive-only array for 7T upper extremity [UE] imaging. In addition, Siemens optimized protocol/sequences were used on a 3T scanner and the resulting images from T1 VIBE and T2 DESS were compared to that obtained at 7T qualitatively and quantitatively [SWI was only qualitatively compared]. DSI studio was utilized to identify nerves based on analysis of diffusion weighted derived fractional anisotropy images. Images of forearm vasculature were extracted using a paint grow manual segmentation method based on MIPAV [Medical Image Processing, Analysis, and Visualization].High resolution and high quality signal-to-noise ratio [SNR] and contrast-to-noise ratio [CNR]-images of the hand, forearm, and elbow were acquired with nearly homogeneous 7T excitation. Measured [performed on the T1 VIBE and T2 DESS sequences] SNR and CNR values were almost doubled at 7T vs. 3T. Cartilage, synovial fluid and tendon structures could be seen with higher clarity in the 7T T1 and T2 weighted images. SWI allowed high resolution and better quality imaging of large and medium sized arteries and veins, capillary networks and arteriovenous anastomoses at 7T when compared to 3T. 7T diffusion weighted sequence [not performed at 3T] demonstrates that the forearm nerves are clearly delineated by fiber tractography. The

  7. MRT letter: Contrast-enhanced computed tomographic imaging of soft callus formation in fracture healing.

    Science.gov (United States)

    Hayward, Lauren Nicole Miller; de Bakker, Chantal Marie-Jeanne; Lusic, Hrvoje; Gerstenfeld, Louis Charles; Grinstaff, Mark W; Morgan, Elise Feng-I

    2012-01-01

    Formation of a cartilaginous soft callus at the site of a bone fracture is a pivotal stage in the healing process. Noninvasive, or even nondestructive, imaging of soft callus formation can be an important tool in experimental and pre-clinical studies of fracture repair. However, the low X-ray attenuation of cartilage renders the soft callus nearly invisible in radiographs. This study utilized a recently developed, cationic, iodinated contrast agent in conjunction with micro-computed tomography to identify cartilage in fracture calluses in the femora of C57BL/6J and C3H/HeJ mice. Fracture calluses were scanned before and after incubation in the contrast agent. The set of pre-incubation images was registered against and then subtracted from the set of post-incubation images, resulting in a three-dimensional map of the locations of cartilage in the callus, as labeled by the contrast agent. This map was then compared to histology from a previous study. The results showed that the locations where the contrast agent collected in relatively high concentrations were similar to those of the cartilage. The contrast agent also identified a significant difference between the two strains of mice in the percentage of the callus occupied by cartilage, indicating that this method of contrast-enhanced computed tomography may be an effective technique for nondestructive, early evaluation of fracture healing. Copyright © 2011 Wiley Periodicals, Inc.

  8. Study of quality perception in medical images based on comparison of contrast enhancement techniques in mammographic images

    Science.gov (United States)

    Matheus, B.; Verçosa, L. B.; Barufaldi, B.; Schiabel, H.

    2014-03-01

    With the absolute prevalence of digital images in mammography several new tools became available for radiologist; such as CAD schemes, digital zoom and contrast alteration. This work focuses in contrast variation and how the radiologist reacts to these changes when asked to evaluated image quality. Three contrast enhancing techniques were used in this study: conventional equalization, CCB Correction [1] - a digitization correction - and value subtraction. A set of 100 images was used in tests from some available online mammographic databases. The tests consisted of the presentation of all four versions of an image (original plus the three contrast enhanced images) to the specialist, requested to rank each one from the best up to worst quality for diagnosis. Analysis of results has demonstrated that CCB Correction [1] produced better images in almost all cases. Equalization, which mathematically produces a better contrast, was considered the worst for mammography image quality enhancement in the majority of cases (69.7%). The value subtraction procedure produced images considered better than the original in 84% of cases. Tests indicate that, for the radiologist's perception, it seems more important to guaranty full visualization of nuances than a high contrast image. Another result observed is that the "ideal" scanner curve does not yield the best result for a mammographic image. The important contrast range is the middle of the histogram, where nodules and masses need to be seen and clearly distinguished.

  9. Dynamic contrast-enhanced magnetic resonance imaging of the sarcopenic muscle

    Energy Technology Data Exchange (ETDEWEB)

    Nicolato, Elena; Farace, Paolo; Asperio, Roberto M; Marzola, Pasquina; Lunati, Ernesto; Sbarbati, Andrea; Osculati, Francesco [Dipartimento di Scienze Morfologico-Biomediche, Sezione di Anatomia ed Istologia, Università di Verona, Verona, I-37194 (Italy)

    2002-06-05

    Studies about capillarity of the aged muscle provided conflicting results and no data are currently available about the magnetic resonance imaging (MRI) in vivo characteristics of the microvascular bed in aged rats. We have studied age-related modifications of the skeletal muscle by in vivo T2-relaxometry and dynamic contrast-enhanced magnetic resonance imaging (CE-MRI) at high field intensity (4.7 T). The aim of the work was to test the hypothesis that the ageing process involves microvessels in skeletal muscle. The study was performed in 4-month-old (n = 6) and 20-month-old (n = 6) rats. At MRI examination, the relaxation time T2 of the gastrocnemius muscle showed no significant difference between these two groups. The kinetic of contrast penetration in the tissue showed that in 4-month-old rats the enhancement values of the signal intensity at different time-points were significantly higher than those found in senescent rats. The reported finding suggests that there is a modification of the microcirculatory function in skeletal muscle of aged rats. This work also demonstrates that CE-MRI allows for an in vivo quantification of the multiple biological processes involving the skeletal muscle during aging. Therefore, CE-MRI could represent a further tool for the follow up of tissue modification and therapeutic intervention both in patients with sarcopenia and in experimental models of this pathology.

  10. Dynamic contrast-enhanced magnetic resonance imaging of the sarcopenic muscle

    International Nuclear Information System (INIS)

    Nicolato, Elena; Farace, Paolo; Asperio, Roberto M; Marzola, Pasquina; Lunati, Ernesto; Sbarbati, Andrea; Osculati, Francesco

    2002-01-01

    Studies about capillarity of the aged muscle provided conflicting results and no data are currently available about the magnetic resonance imaging (MRI) in vivo characteristics of the microvascular bed in aged rats. We have studied age-related modifications of the skeletal muscle by in vivo T2-relaxometry and dynamic contrast-enhanced magnetic resonance imaging (CE-MRI) at high field intensity (4.7 T). The aim of the work was to test the hypothesis that the ageing process involves microvessels in skeletal muscle. The study was performed in 4-month-old (n = 6) and 20-month-old (n = 6) rats. At MRI examination, the relaxation time T2 of the gastrocnemius muscle showed no significant difference between these two groups. The kinetic of contrast penetration in the tissue showed that in 4-month-old rats the enhancement values of the signal intensity at different time-points were significantly higher than those found in senescent rats. The reported finding suggests that there is a modification of the microcirculatory function in skeletal muscle of aged rats. This work also demonstrates that CE-MRI allows for an in vivo quantification of the multiple biological processes involving the skeletal muscle during aging. Therefore, CE-MRI could represent a further tool for the follow up of tissue modification and therapeutic intervention both in patients with sarcopenia and in experimental models of this pathology

  11. Maximum Entropy Approach in Dynamic Contrast-Enhanced Magnetic Resonance Imaging.

    Science.gov (United States)

    Farsani, Zahra Amini; Schmid, Volker J

    2017-01-01

    In the estimation of physiological kinetic parameters from Dynamic Contrast-Enhanced Magnetic Resonance Imaging (DCE-MRI) data, the determination of the arterial input function (AIF) plays a key role. This paper proposes a Bayesian method to estimate the physiological parameters of DCE-MRI along with the AIF in situations, where no measurement of the AIF is available. In the proposed algorithm, the maximum entropy method (MEM) is combined with the maximum a posterior approach (MAP). To this end, MEM is used to specify a prior probability distribution of the unknown AIF. The ability of this method to estimate the AIF is validated using the Kullback-Leibler divergence. Subsequently, the kinetic parameters can be estimated with MAP. The proposed algorithm is evaluated with a data set from a breast cancer MRI study. The application shows that the AIF can reliably be determined from the DCE-MRI data using MEM. Kinetic parameters can be estimated subsequently. The maximum entropy method is a powerful tool to reconstructing images from many types of data. This method is useful for generating the probability distribution based on given information. The proposed method gives an alternative way to assess the input function from the existing data. The proposed method allows a good fit of the data and therefore a better estimation of the kinetic parameters. In the end, this allows for a more reliable use of DCE-MRI. Schattauer GmbH.

  12. Contrast-enhanced magnetic resonance imaging of pulmonary lesions: Description of a technique aiming clinical practice

    International Nuclear Information System (INIS)

    Koenigkam-Santos, Marcel; Optazaite, Elzbieta; Sommer, Gregor; Safi, Seyer; Heussel, Claus Peter; Kauczor, Hans-Ulrich

    2015-01-01

    To propose a technique for evaluation of pulmonary lesions using contrast-enhanced MRI; to assess morphological patterns of enhancement and correlate quantitative analysis with histopathology. Material and methods: Thirty-six patients were prospectively studied. Volumetric-interpolated T1W images were obtained during consecutive breath holds after bolus triggered contrast injection. Volume coverage of first three acquisitions was limited (higher temporal resolution) and last acquisition obtained at 4th min. Two radiologists individually evaluated the patterns of enhancement. Region-of-interest-based signal intensity (SI)-time curves were created to assess quantitative parameters. Results: Readers agreed moderately to substantially concerning lesions’ enhancement pattern. SI-time curves could be created for all lesions. In comparison to benign, malignant lesions showed higher values of maximum enhancement, early peak, slope and 4th min enhancement. Early peak >15% showed 100% sensitivity to detect malignancy, maximum enhancement >40% showed 100% specificity. Conclusions: The proposed technique is robust, simple to perform and can be applied in clinical scenario. It allows visual evaluation of enhancement pattern/progression together with creation of SI-time curves and assessment of derived quantitative parameters. Perfusion analysis was highly sensitive to detect malignancy, in accordance to what is recommended by most recent guidelines on imaging evaluation of pulmonary lesions

  13. Quantitative dynamic contrast-enhanced MR imaging analysis of complex adnexal masses: a preliminary study

    International Nuclear Information System (INIS)

    Thomassin-Naggara, Isabelle; Balvay, Daniel; Aubert, Emilie; Bazot, Marc; Darai, Emile; Rouzier, Roman; Cuenod, Charles A.

    2012-01-01

    To evaluate the ability of quantitative dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) to differentiate malignant from benign adnexal tumours. Fifty-six women with 38 malignant and 18 benign tumours underwent MR imaging before surgery for complex adnexal masses. Microvascular parameters were extracted from high temporal resolution DCE-MRI series, using a pharmacokinetic model in the solid tissue of adnexal tumours. These parameters were tissue blood flow (F T ), blood volume fraction (Vb), permeability-surface area product (PS), interstitial volume fraction (Ve), lag time (Dt) and area under the enhancing curve (rAUC). Area under the receiver operating curve (AUROC) was calculated as a descriptive tool to assess the overall discrimination of parameters. Malignant tumours displayed higher F T , Vb, rAUC and lower Ve than benign tumours (P T was the most relevant factor for discriminating malignant from benign tumours (AUROC = 0.86). Primary ovarian invasive tumours displayed higher F T and shorter Dt than borderline tumours. Malignant adnexal tumours with associated peritoneal carcinomatosis at surgery displayed a shorter Dt than those without peritoneal carcinomatosis at surgery (P = 0.01). Quantitative DCE-MRI is a feasible and accurate technique to differentiate malignant from benign adnexal tumours and could potentially help oncologists with management decisions. (orig.)

  14. Quantitative dynamic contrast-enhanced MR imaging analysis of complex adnexal masses: a preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Thomassin-Naggara, Isabelle [Hopital Tenon, Assistance Publique-Hopitaux de Paris, Department of Radiology, Paris (France); Laboratoire de recherche en imagerie - UMR 970 INSERM - Universite Rene Descartes, Paris (France); Service de Radiologie, Hopital Tenon, Paris (France); Balvay, Daniel [Laboratoire de recherche en imagerie - UMR 970 INSERM - Universite Rene Descartes, Paris (France); Aubert, Emilie; Bazot, Marc [Hopital Tenon, Assistance Publique-Hopitaux de Paris, Department of Radiology, Paris (France); Darai, Emile; Rouzier, Roman [Hopital Tenon, Assistance Publique-Hopitaux de Paris, Department of Gynaecology-Obstetrics, Paris (France); Cuenod, Charles A. [Laboratoire de recherche en imagerie - UMR 970 INSERM - Universite Rene Descartes, Paris (France); Hopital Europeen Georges Pompidou (HEGP), Department of Radiology, Paris (France)

    2012-04-15

    To evaluate the ability of quantitative dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) to differentiate malignant from benign adnexal tumours. Fifty-six women with 38 malignant and 18 benign tumours underwent MR imaging before surgery for complex adnexal masses. Microvascular parameters were extracted from high temporal resolution DCE-MRI series, using a pharmacokinetic model in the solid tissue of adnexal tumours. These parameters were tissue blood flow (F{sub T}), blood volume fraction (Vb), permeability-surface area product (PS), interstitial volume fraction (Ve), lag time (Dt) and area under the enhancing curve (rAUC). Area under the receiver operating curve (AUROC) was calculated as a descriptive tool to assess the overall discrimination of parameters. Malignant tumours displayed higher F{sub T}, Vb, rAUC and lower Ve than benign tumours (P < 0.0001, P = 0.0006, P = 0.04 and P = 0.0002, respectively). F{sub T} was the most relevant factor for discriminating malignant from benign tumours (AUROC = 0.86). Primary ovarian invasive tumours displayed higher F{sub T} and shorter Dt than borderline tumours. Malignant adnexal tumours with associated peritoneal carcinomatosis at surgery displayed a shorter Dt than those without peritoneal carcinomatosis at surgery (P = 0.01). Quantitative DCE-MRI is a feasible and accurate technique to differentiate malignant from benign adnexal tumours and could potentially help oncologists with management decisions. (orig.)

  15. Contrast-enhanced magnetic resonance imaging of pulmonary lesions: Description of a technique aiming clinical practice

    Energy Technology Data Exchange (ETDEWEB)

    Koenigkam-Santos, Marcel, E-mail: marcelk46@yahoo.com.br [Department of Diagnostic and Interventional Radiology, University of Heidelberg, Im Neuenheimer Feld 110, 69120 Heidelberg (Germany); Radiology Department, German Cancer Research Center (Deutsches Krebsforschungszentrum – DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany); Department of Radiology, University Hospital of the School of Medicine of Ribeirao Preto, University of Sao Paulo, Avenida Bandeirantes 3900, Campus Universitario Monte Alegre, 14048 900 Ribeirao Preto, Sao Paulo (Brazil); Optazaite, Elzbieta, E-mail: optazaite@andrulis.eu [Diagnostic and Interventional Radiology with Nuclear Medicine, Chest Clinic (Thoraxklinik), University of Heidelberg, Amalienstraße 5, 69126 Heidelberg (Germany); Sommer, Gregor, E-mail: gregor.sommer@usb.ch [Clinic of Radiology and Nuclear Medicine, University Hospital Basel, Petersgraben 4, CH-4031 Basel (Switzerland); Safi, Seyer, E-mail: seyer.safi@gmail.com [Surgery Department, Chest Clinic (Thoraxklinik), University of Heidelberg, Amalienstraße 5, 69126 Heidelberg (Germany); Heussel, Claus Peter, E-mail: heussel@uni-heidelberg.de [Diagnostic and Interventional Radiology with Nuclear Medicine, Chest Clinic (Thoraxklinik), University of Heidelberg, Amalienstraße 5, 69126 Heidelberg (Germany); Translational Lung Research Center (TLRC), Member of the German Center for Lung Research (DZL), Im Neuenheimer Feld 350, 69120 Heidelberg (Germany); Kauczor, Hans-Ulrich, E-mail: hans-ulrich.kauczor@med.uni-heidelberg.de [Department of Diagnostic and Interventional Radiology, University of Heidelberg, Im Neuenheimer Feld 110, 69120 Heidelberg (Germany); Translational Lung Research Center (TLRC), Member of the German Center for Lung Research (DZL), Im Neuenheimer Feld 350, 69120 Heidelberg (Germany); and others

    2015-01-15

    To propose a technique for evaluation of pulmonary lesions using contrast-enhanced MRI; to assess morphological patterns of enhancement and correlate quantitative analysis with histopathology. Material and methods: Thirty-six patients were prospectively studied. Volumetric-interpolated T1W images were obtained during consecutive breath holds after bolus triggered contrast injection. Volume coverage of first three acquisitions was limited (higher temporal resolution) and last acquisition obtained at 4th min. Two radiologists individually evaluated the patterns of enhancement. Region-of-interest-based signal intensity (SI)-time curves were created to assess quantitative parameters. Results: Readers agreed moderately to substantially concerning lesions’ enhancement pattern. SI-time curves could be created for all lesions. In comparison to benign, malignant lesions showed higher values of maximum enhancement, early peak, slope and 4th min enhancement. Early peak >15% showed 100% sensitivity to detect malignancy, maximum enhancement >40% showed 100% specificity. Conclusions: The proposed technique is robust, simple to perform and can be applied in clinical scenario. It allows visual evaluation of enhancement pattern/progression together with creation of SI-time curves and assessment of derived quantitative parameters. Perfusion analysis was highly sensitive to detect malignancy, in accordance to what is recommended by most recent guidelines on imaging evaluation of pulmonary lesions.

  16. Dynamic contrast-enhanced magnetic resonance imaging of the sarcopenic muscle

    Directory of Open Access Journals (Sweden)

    Sbarbati Andrea

    2002-06-01

    Full Text Available Abstract Background Studies about capillarity of the aged muscle provided conflicting results and no data are currently available about the magnetic resonance imaging (MRI in vivo characteristics of the microvascular bed in aged rats. We have studied age-related modifications of the skeletal muscle by in vivo T2-relaxometry and dynamic contrast-enhanced magnetic resonance imaging (CE-MRI at high field intensity (4.7 T. The aim of the work was to test the hypothesis that the ageing process involves microvessels in skeletal muscle. Methods The study was performed in 4-month-old (n = 6 and 20-month-old (n = 6 rats. Results At MRI examination, the relaxation time T2 of the gastrocnemius muscle showed no significant difference between these two groups. The kinetic of contrast penetration in the tissue showed that in 4-month-old rats the enhancement values of the signal intensity at different time-points were significantly higher than those found in senescent rats. Conclusion The reported finding suggests that there is a modification of the microcirculatory function in skeletal muscle of aged rats. This work also demonstrates that CE-MRI allows for an in vivo quantification of the multiple biological processes involving the skeletal muscle during aging. Therefore, CE-MRI could represent a further tool for the follow up of tissue modification and therapeutic intervention both in patients with sarcopenia and in experimental models of this pathology.

  17. Contrast Enhanced US in the Abdomen

    International Nuclear Information System (INIS)

    Chung, Yong Eun; Kim, Ki Whang

    2012-01-01

    Contrast enhanced ultrasound, which was introduced in 1996, has been widely used in Europe and Eastern Asia. Ultrasound contrast agent can be classified as first generation and second generation, depending on the gas within the microbubble. With the first generation contrast agent, the high MI technique was used, and only intermittent scanning was possible due to destruction of the microbubble during scanning. Use of the second generation contrast agent with the low MI technique makes continuous scanning possible. Contrast enhanced US can be used in detection and differentiation of focal liver lesions. It is also helpful for monitoring of radiofrequency ablation and for targeting of US guided biopsy. Currently, because morphologic criteria alone may not reflect the response of the tumor to treatment, new criteria are needed for treatment evaluation after administration of anti-angiogenic agents. Contrast enhanced US could provide quantitative markers for evaluation of the response to treatment via use of dynamic contrast enhanced US. Due to cost-effectiveness, contrast enhanced US is not yet widely used in Korea; however, considering recent issues regarding contrast agent related adverse reaction, such as contrast induced nephropathy and nephrogenic systemic fibrosis, and radiation exposure, contrast enhanced US might be more widely used in Korea, as an alternative imaging modality in the future.

  18. Colorectal liver metastases: contrast agent diffusion coefficient for quantification of contrast enhancement heterogeneity at MR imaging.

    Science.gov (United States)

    Jia, Guang; O'Dell, Craig; Heverhagen, Johannes T; Yang, Xiangyu; Liang, Jiachao; Jacko, Richard V; Sammet, Steffen; Pellas, Theodore; Cole, Patricia; Knopp, Michael V

    2008-09-01

    To describe and determine the reproducibility of a simplified model to quantitatively measure heterogeneous intralesion contrast agent diffusion in colorectal liver metastases. This HIPAA-compliant retrospective study received institutional review board approval, and written informed consent was obtained from 14 patients (mean age, 61 years +/- 9 [standard deviation]; range, 41-78 years), including 10 men (mean age, 65 years +/- 8; range, 47-78 years) and four women (mean age, 54 years +/- 9; range, 41-59 years), with colorectal liver metastases. Magnetic resonance (MR) imaging was performed twice (first baseline MR image [B(1)] and second baseline MR image [B(2)]) in a single target lesion prior to therapy. Dynamic contrast material-enhanced MR imaging was performed by using a saturation-recovery fast gradient-echo sequence. A simplified contrast agent diffusion model was proposed, and a contrast agent diffusion coefficient (CDC) was calculated. The reproducibility of the CDC measurement was evaluated by using the Bland-Altman plot and a linear regression model. The mean CDC was 0.22 mm(2)/sec (range, 0.01-0.73 mm(2)/sec) on B(1) and 0.24 mm(2)/sec (range, 0.01-0.71 mm(2)/sec) on B(2), with an intraclass correlation coefficient of 0.91 (P < .0001). Bland-Altman plot showed good agreement, with a mean difference in measurement pairs of 0.017 mm(2)/sec +/- 0.096. The slope from the linear regression model was 0.89 (95% confidence interval: 0.63, 1.15) and the intercept was 0.01 (95% confidence interval: -0.08, 0.09). The CDC enables a quantitative description of contrast enhancement heterogeneity in lesions. Given the high reproducibility of the CDC metric, CDC appears promising for further qualification as an imaging biomarker of change measurement in response assessment. http://radiology.rsnajnls.org/cgi/content/full/248/3/901/DC1. RSNA, 2008

  19. Contrast-enhanced photoacoustic imaging with an optical wavelength of 1064 nm

    Science.gov (United States)

    Kim, Jeesu; Park, Sara; Park, Gyeong Bae; Choi, Wonseok; Jeong, Unyong; Kim, Chulhong

    2018-02-01

    Photoacoustic (PA) imaging is a biomedical imaging method that can provide both structural and functional information of living tissues beyond the optical diffusion limit by combining the concepts of conventional optical and ultrasound imaging methods. Although endogenous chromophores can be utilized to acquire PA images of biological tissues, exogenous contrast agents that absorb near-infrared (NIR) lights have been extensively explored to improve the contrast and penetration depth of PA images. Here, we demonstrate Bi2Se3 nanoplates, that strongly absorbs NIR lights, as a contrast agent for PA imaging. In particularly, the Bi2Se3 nanoplates produce relatively strong PA signals with an optical wavelength of 1064 nm, which has several advantages for deep tissue imaging including: (1) relatively low absorption by other intrinsic chromophores, (2) cost-effective light source using Nd:YAG laser, and (3) higher available energy than other NIR lights according to American National Standards Institute (ANSI) safety limit. We have investigated deep tissue imaging capability of the Bi2Se3 nanoplates by acquiring in vitro PA images of microtubes under chicken breast tissues. We have also acquired in vivo PA images of bladders, gastrointestinal tracts, and sentinel lymph nodes in mice after injection of the Bi2Se3 nanoplates to verify their applicability to a variety of biomedical research. The results show the promising potential of the Bi2Se3 nanoplates as a PA contrast agent for deep tissue imaging with an optical wavelength of 1064 nm.

  20. Correlative Study of Angiogenesis and Dynamic Contrast-Enhanced Magnetic Resonance Imaging Features of Hepatocellular Carcinoma

    International Nuclear Information System (INIS)

    Wang, B.; Gao, Z.Q.; Yan, X.

    2005-01-01

    Purpose: To explore the correlation between contrast-enhancement patterns on dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and angiogenesis by analyzing microvessel density (MVD), vascular endothelial growth factor (VEGF), and P53 protein expression in hepatocellular carcinoma (HCC). Material and Methods: MRI was performed with a GE Signa 5T MR scanner using SE and FMPSPGR sequences in 30 patients (38 lesions) during the period October 1998 to March 2000. All had histopathologically proven HCC. MR images were reviewed/analyzed retrospectively. The 30 patients were between 35 and 65 years of age. SE T1WI, PDWI, and T2WI were acquired initially. The FMPSPGR sequence was acquired in the same position. The DCE-MRI was performed in the arterial, portal vein, and delay phase after a bolus injection of Gd-DTPA. The specimens were stained immunohistochemically for CD34, VEGF, and P53. MVD was highlighted by anti-CD34 antibody staining. The enhancement features of HCC lesions were studied correlatively with the tumor MVD, VEGF, and P53 expression at protein level. Results: In the arterial phase, the results showed that MVD of HCC in the high-enhancement group (229.76±80.96) was higher than that in the equal-enhancement (173.09±61.38) and low-enhancement groups (153.00±108.58) (P <0.01, respectively). VEGF expression of HCC in the high-enhancement group (68.42%) was higher than that in the equal-enhancement (36.36%) and low-enhancement groups (38.89%) (P <0.05, respectively). In the portal vein phase, MVD of HCC in the enhancement group (259.80±93.30) was higher than that in the non-enhancement group (178.64±92.65) (P <0.05). No significant correlation was found between VEGF expression and the enhancement feature in the portal vein phase. In the delay phase, MVD of HCC in the ring-enhancement group (269.06±57.89) was significantly higher than that in the non-ring-enhancement group (144.10±88.90) (P <0.01). There was a significant difference in VEGF

  1. Dynamic contrast-enhanced MR imaging of endometrial cancer. Optimizing the imaging delay for tumour-myometrium contrast

    International Nuclear Information System (INIS)

    Park, Sung Bin; Moon, Min Hoan; Sung, Chang Kyu; Oh, Sohee; Lee, Young Ho

    2014-01-01

    To investigate the optimal imaging delay time of dynamic contrast-enhanced magnetic resonance (MR) imaging in women with endometrial cancer. This prospective single-institution study was approved by the institutional review board, and informed consent was obtained from the participants. Thirty-five women (mean age, 54 years; age range, 29-66 years) underwent dynamic contrast-enhanced MR imaging with a temporal resolution of 25-40 seconds. The signal intensity difference ratios between the myometrium and endometrial cancer were analyzed to investigate the optimal imaging delay time using single change-point analysis. The optimal imaging delay time for appropriate tumour-myometrium contrast ranged from 31.7 to 268.1 seconds. The median optimal imaging delay time was 91.3 seconds, with an interquartile range of 46.2 to 119.5 seconds. The median signal intensity difference ratios between the myometrium and endometrial cancer were 0.03, with an interquartile range of -0.01 to 0.06, on the pre-contrast MR imaging and 0.20, with an interquartile range of 0.15 to 0.25, on the post-contrast MR imaging. An imaging delay of approximately 90 seconds after initiating contrast material injection may be optimal for obtaining appropriate tumour-myometrium contrast in women with endometrial cancer. (orig.)

  2. MR imaging of spine and spinal canal neoplasms: value of Gd-DTPA contrast enhancement

    International Nuclear Information System (INIS)

    Paprzycki, W.; Gradzki, J.; Sosnowski, P.; Stajgis, M.

    1994-01-01

    Value of Gadolinium-DTPA contrast enhancement in diagnosis of neoplastic diseases of spinal canal was estimated on the basis of retrospective analysis of MR examinations performed in 75 patients. The analyzed material consisted of 15 cases of intramedullary tumors (group 1.), 38 of subdural extramedullary (group 2.) and 22 extradural ones (group 3.). Contrast enhanced MR contributed significant information to the final diagnosis in all groups. The utmost significance of Gd-DTPA contrast enhancement was ascertained in group 1. Authors conclude that contrast enhancement with Gd-DTPA is indispensable in all these cases of spinal canal neoplasms, where non-contrast MR did not reveal pathologic changes in optimal manner. (author)

  3. Development of low-dose photon-counting contrast-enhanced tomosynthesis with spectral imaging.

    Science.gov (United States)

    Schmitzberger, Florian F; Fallenberg, Eva Maria; Lawaczeck, Rüdiger; Hemmendorff, Magnus; Moa, Elin; Danielsson, Mats; Bick, Ulrich; Diekmann, Susanne; Pöllinger, Alexander; Engelken, Florian J; Diekmann, Felix

    2011-05-01

    To demonstrate the feasibility of low-dose photon-counting tomosynthesis in combination with a contrast agent (contrast material-enhanced tomographic mammography) for the differentiation of breast cancer. All studies were approved by the institutional review board, and all patients provided written informed consent. A phantom model with wells of iodinated contrast material (3 mg of iodine per milliliter) 1, 2, 5, 10, and 15 mm in diameter was assessed. Nine patients with malignant lesions and one with a high-risk lesion (atypical papilloma) were included (all women; mean age, 60.7 years). A multislit photon-counting tomosynthesis system was utilized (spectral imaging) to produce both low- and high-energy tomographic data (below and above the k edge of iodine, respectively) in a single scan, which allowed for dual-energy visualization of iodine. Images were obtained prior to contrast material administration and 120 and 480 seconds after contrast material administration. Four readers independently assessed the images along with conventional mammograms, ultrasonographic images, and magnetic resonance images. Glandular dose was estimated. Contrast agent was visible in the phantom model with simulated spherical tumor diameters as small as 5 mm. The average glandular dose was measured as 0.42 mGy per complete spectral imaging tomosynthesis scan of one breast. Because there were three time points (prior to contrast medium administration and 120 and 480 seconds after contrast medium administration), this resulted in a total dose of 1.26 mGy for the whole procedure in the breast with the abnormality. Seven of 10 cases were categorized as Breast Imaging Reporting and Data System score of 4 or higher by all four readers when reviewing spectral images in combination with mammograms. One lesion near the chest wall was not captured on the spectral image because of a positioning problem. The use of contrast-enhanced tomographic mammography has been demonstrated successfully in

  4. Assessing tumor extent on contrast-enhanced spectral mammography versus full-field digital mammography and ultrasound.

    Science.gov (United States)

    Patel, Bhavika K; Garza, Sandra Alheli; Eversman, Sarah; Lopez-Alvarez, Yania; Kosiorek, Heidi; Pockaj, Barbara A

    To compare breast cancer size measurements on full-field digital mammography (FFDM), contrast-enhanced spectral mammography (CEDM), and ultrasound (US), with histologic tumor size used as the reference standard. Material and methods The HIPAA complaint, IRB approved study comprised 88 women with newly diagnosed breast cancer who underwent FFDM and CEDM;74 also had US. Breast density, histologic subtype, and maximum tumor measurements were recorded. Pearson correlation coefficients for FFDM, US, and CEDM vs histopathology were 0.598, 0.639, and 0.859, respectively (P<0.001). The following correlation coefficients were calculated for dense breasts (n=48): histopathology vs FFDM (0.555), US (0.633), and CEDM (0.843) (P<0.001); for nondense breasts (n=40), they were FFDM (0.618), US (0.512), and CEDM (0.885) (P<0.001). For size difference, the mean (SD) for histopathology vs FFDM, US, and CEDM was -1.3 (11.9) mm, -2.8 (11.1) mm, and 2.9 (9.5) mm, respectively. Limits of agreement were -24.8 to 22.0mm, -24.5 to 18.8mm, and -15.6 to 21.4mm, respectively. In patients with biopsy-proven malignancy, size measurements correlated well with histopathologic size, and were higher on CEDM than those for FFDM and US in patients with dense or nondense breasts. The added value of CEDM as a supplement to FFDM in determining tumor size, however, was greater in patients with dense breasts. CEDM may be a promising alternative preoperative measurement tool for breast cancer patients with dense breasts and/or limited access or contraindications to MRI. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Quantitative contrast-enhanced ultrasound evaluation of pathological complete response in patients with locally advanced breast cancer receiving neoadjuvant chemotherapy.

    Science.gov (United States)

    Wan, Cai-Feng; Liu, Xue-Song; Wang, Lin; Zhang, Jie; Lu, Jin-Song; Li, Feng-Hua

    2018-06-01

    To clarify whether the quantitative parameters of contrast-enhanced ultrasound (CEUS) can be used to predict pathological complete response (pCR) in patients with locally advanced breast cancer receiving neoadjuvant chemotherapy (NAC). Fifty-one patients with histologically proved locally advanced breast cancer scheduled for NAC were enrolled. The quantitative data for CEUS and the tumor diameter were collected at baseline and before surgery, and compared with the pathological response. Multiple logistic regression analysis was performed to examine quantitative parameters at CEUS and the tumor diameter to predict the pCR, and receiver operating characteristic (ROC) curve analysis was used as a summary statistic. Multiple logistic regression analysis revealed that PEAK (the maximum intensity of the time-intensity curve during bolus transit), PEAK%, TTP% (time to peak), and diameter% were significant independent predictors of pCR, and the area under the ROC curve was 0.932(Az 1 ), and the sensitivity and specificity to predict pCR were 93.7% and 80.0%. The area under the ROC curve for the quantitative parameters was 0.927(Az 2 ), and the sensitivity and specificity to predict pCR were 81.2% and 94.3%. For diameter%, the area under the ROC curve was 0.786 (Az 3 ), and the sensitivity and specificity to predict pCR were 93.8% and 54.3%. The values of Az 1 and Az 2 were significantly higher than that of Az 3 (P = 0.027 and P = 0.034, respectively). However, there was no significant difference between the values of Az 1 and Az 2 (P = 0.825). Quantitative analysis of tumor blood perfusion with CEUS is superior to diameter% to predict pCR, and can be used as a functional technique to evaluate tumor response to NAC. Copyright © 2018. Published by Elsevier B.V.

  6. Changes in the micro-circulation of skeletal muscle due to varied isometric exercise assessed by contrast-enhanced ultrasound

    International Nuclear Information System (INIS)

    Krix, Martin; Weber, Marc-Andre; Kauczor, Hans-Ulrich; Delorme, Stefan; Krakowski-Roosen, Holger

    2010-01-01

    Purpose: To quantitatively assess local muscle micro-circulation with real-time contrast-enhanced ultrasound (CEUS) during different exercises and compare the results with performed muscle work and global blood flow. Materials and methods: Sixteen low mechanical index CEUS examinations of the right lower leg flexors of healthy volunteers were performed using a continuous infusion of SonoVue (4.8 mL/300 s). Several muscle perfusion parameters were extracted from derived CEUS signal intensity time curves during different isometric exercises (10-50% of maximum individual strength for 20-30 s) and then correlated with the performed muscle work or force, and the whole lower leg blood flow which we measured simultaneously by venous occlusion plethysmography (VOP). Results: The shapes of the CEUS curve during and after exercise differed individually depending on the performed muscle work. The maximum blood volume MAX was observed only after exercise cessation and was significantly correlated with the performed muscle force (r = 0.77, p < 0.0001). The blood volume over exercise time was inversely correlated with the spent muscle work (r = -0.60, p = 0.006). CEUS and VOP measurements correlated only at rest and after the exercise. During exercise, mean CEUS local blood volume decreased (from 3.48 to 2.19 (∼mL)), while mean VOP global blood flow increased (mean, from 3.96 to 7.71 mL/100 mg/min). Conclusion: Real-time low-MI CEUS provides complementary information about the local muscle micro-circulation compared to established blood flow measures. CEUS may be used for a better understanding of muscle perfusion physiology and in the diagnosis of micro-circulation alterations such as in peripheral arterial occlusive disease or diabetic angiopathy.

  7. Differentiating perforated from non-perforated appendicitis on contrast-enhanced magnetic resonance imaging

    International Nuclear Information System (INIS)

    Rosenbaum, Daniel G.; Kovanlikaya, Arzu; Askin, Gulce; Beneck, Debra M.

    2017-01-01

    The role of magnetic resonance imaging (MRI) in pediatric appendicitis is increasing; MRI findings predictive of appendiceal perforation have not been specifically evaluated. To assess the performance of MRI in differentiating perforated from non-perforated appendicitis. A retrospective review of pediatric patients undergoing contrast-enhanced MRI and subsequent appendectomy was performed, with surgicopathological confirmation of perforation. Appendiceal diameter and the following 10 MRI findings were assessed: appendiceal restricted diffusion, wall defect, appendicolith, periappendiceal free fluid, remote free fluid, restricted diffusion within free fluid, abscess, peritoneal enhancement, ileocecal wall thickening and ileus. Two-sample t-test and chi-square tests were used to analyze continuous and discrete data, respectively. Sensitivity and specificity for individual MRI findings were calculated and optimal thresholds for measures of accuracy were selected. Seventy-seven patients (mean age: 12.2 years) with appendicitis were included, of whom 22 had perforation. The perforated group had a larger mean appendiceal diameter and mean number of MRI findings than the non-perforated group (12.3 mm vs. 8.6 mm; 5.0 vs. 2.0, respectively). Abscess, wall defect and restricted diffusion within free fluid had the greatest specificity for perforation (1.00, 1.00 and 0.96, respectively) but low sensitivity (0.36, 0.25 and 0.32, respectively). The receiver operator characteristic curve for total number of MRI findings had an area under the curve of 0.92, with an optimal threshold of 3.5. A threshold of any 4 findings had the best ability to accurately discriminate between perforated and non-perforated cases, with a sensitivity of 82% and specificity of 85%. Contrast-enhanced MRI can differentiate perforated from non-perforated appendicitis. The presence of multiple findings increases diagnostic accuracy, with a threshold of any four findings optimally discriminating between

  8. Differentiating perforated from non-perforated appendicitis on contrast-enhanced magnetic resonance imaging.

    Science.gov (United States)

    Rosenbaum, Daniel G; Askin, Gulce; Beneck, Debra M; Kovanlikaya, Arzu

    2017-10-01

    The role of magnetic resonance imaging (MRI) in pediatric appendicitis is increasing; MRI findings predictive of appendiceal perforation have not been specifically evaluated. To assess the performance of MRI in differentiating perforated from non-perforated appendicitis. A retrospective review of pediatric patients undergoing contrast-enhanced MRI and subsequent appendectomy was performed, with surgicopathological confirmation of perforation. Appendiceal diameter and the following 10 MRI findings were assessed: appendiceal restricted diffusion, wall defect, appendicolith, periappendiceal free fluid, remote free fluid, restricted diffusion within free fluid, abscess, peritoneal enhancement, ileocecal wall thickening and ileus. Two-sample t-test and chi-square tests were used to analyze continuous and discrete data, respectively. Sensitivity and specificity for individual MRI findings were calculated and optimal thresholds for measures of accuracy were selected. Seventy-seven patients (mean age: 12.2 years) with appendicitis were included, of whom 22 had perforation. The perforated group had a larger mean appendiceal diameter and mean number of MRI findings than the non-perforated group (12.3 mm vs. 8.6 mm; 5.0 vs. 2.0, respectively). Abscess, wall defect and restricted diffusion within free fluid had the greatest specificity for perforation (1.00, 1.00 and 0.96, respectively) but low sensitivity (0.36, 0.25 and 0.32, respectively). The receiver operator characteristic curve for total number of MRI findings had an area under the curve of 0.92, with an optimal threshold of 3.5. A threshold of any 4 findings had the best ability to accurately discriminate between perforated and non-perforated cases, with a sensitivity of 82% and specificity of 85%. Contrast-enhanced MRI can differentiate perforated from non-perforated appendicitis. The presence of multiple findings increases diagnostic accuracy, with a threshold of any four findings optimally discriminating between

  9. Differentiating perforated from non-perforated appendicitis on contrast-enhanced magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Rosenbaum, Daniel G.; Kovanlikaya, Arzu [New York-Presbyterian Hospital/Weill Cornell Medicine, Division of Pediatric Radiology, New York, NY (United States); Askin, Gulce [Weill Cornell Medical College, Division of Biostatistics and Epidemiology, New York, NY (United States); Beneck, Debra M. [New York-Presbyterian Hospital/Weill Cornell Medicine, Department of Pathology, New York, NY (United States)

    2017-10-15

    The role of magnetic resonance imaging (MRI) in pediatric appendicitis is increasing; MRI findings predictive of appendiceal perforation have not been specifically evaluated. To assess the performance of MRI in differentiating perforated from non-perforated appendicitis. A retrospective review of pediatric patients undergoing contrast-enhanced MRI and subsequent appendectomy was performed, with surgicopathological confirmation of perforation. Appendiceal diameter and the following 10 MRI findings were assessed: appendiceal restricted diffusion, wall defect, appendicolith, periappendiceal free fluid, remote free fluid, restricted diffusion within free fluid, abscess, peritoneal enhancement, ileocecal wall thickening and ileus. Two-sample t-test and chi-square tests were used to analyze continuous and discrete data, respectively. Sensitivity and specificity for individual MRI findings were calculated and optimal thresholds for measures of accuracy were selected. Seventy-seven patients (mean age: 12.2 years) with appendicitis were included, of whom 22 had perforation. The perforated group had a larger mean appendiceal diameter and mean number of MRI findings than the non-perforated group (12.3 mm vs. 8.6 mm; 5.0 vs. 2.0, respectively). Abscess, wall defect and restricted diffusion within free fluid had the greatest specificity for perforation (1.00, 1.00 and 0.96, respectively) but low sensitivity (0.36, 0.25 and 0.32, respectively). The receiver operator characteristic curve for total number of MRI findings had an area under the curve of 0.92, with an optimal threshold of 3.5. A threshold of any 4 findings had the best ability to accurately discriminate between perforated and non-perforated cases, with a sensitivity of 82% and specificity of 85%. Contrast-enhanced MRI can differentiate perforated from non-perforated appendicitis. The presence of multiple findings increases diagnostic accuracy, with a threshold of any four findings optimally discriminating between

  10. Dynamic contrast-enhanced magnetic resonance imaging of the wrist in children with juvenile idiopathic arthritis

    Energy Technology Data Exchange (ETDEWEB)

    Nusman, Charlotte M. [Emma Children' s Hospital, Department of Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Academic Medical Center, Amsterdam (Netherlands); Academic Medical Center, Department of Radiology, Amsterdam (Netherlands); Lavini, Cristina; Hemke, Robert; Caan, Matthan W.A.; Maas, Mario [Academic Medical Center, Department of Radiology, Amsterdam (Netherlands); Schonenberg-Meinema, Dieneke; Berg, J.M. van den; Kuijpers, Taco W. [Emma Children' s Hospital, Department of Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Academic Medical Center, Amsterdam (Netherlands); Dolman, Koert M. [Sint Lucas Andreas Hospital, Department of Pediatrics, Amsterdam (Netherlands); Reade Institute location Jan van Breemen, Department of Pediatric Rheumatology, Amsterdam (Netherlands); Rossum, Marion A.J. van [Reade Institute location Jan van Breemen, Department of Pediatric Rheumatology, Amsterdam (Netherlands); Emma Children' s Hospital, Department of Pediatrics, Academic Medical Center, Amsterdam (Netherlands)

    2017-02-15

    Dynamic contrast-enhanced MRI provides information on the heterogeneity of the synovium, the primary target of disease in children with juvenile idiopathic arthritis (JIA). To evaluate the feasibility of dynamic contrast-enhanced MRI in the wrist of children with JIA using conventional descriptive measures and time-intensity-curve shape analysis. To explore the association between enhancement characteristics and clinical disease status. Thirty-two children with JIA and wrist involvement underwent dynamic contrast-enhanced MRI with movement-registration and were classified using validated criteria as clinically active (n = 27) or inactive (n = 5). Outcome measures included descriptive parameters and the classification into time-intensity-curve shapes, which represent the patterns of signal intensity change over time. Differences in dynamic contrast-enhanced MRI outcome measures between clinically active and clinically inactive disease were analyzed and correlation with the Juvenile Arthritis Disease Activity Score was determined. Comprehensive evaluation of disease status was technically feasible and the quality of the dynamic dataset was improved by movement registration. The conventional descriptive measure maximum enhancement differed significantly between clinically active and inactive disease (P = 0.019), whereas time-intensity-curve shape analysis showed no differences. Juvenile Arthritis Disease Activity Score correlated moderately with enhancing volume (P = 0.484). Dynamic contrast-enhanced MRI is a promising biomarker for evaluating disease status in children with JIA and wrist involvement. Conventional descriptive dynamic contrast-enhanced MRI measures are better associated with clinically active disease than time-intensity-curve shape analysis. (orig.)

  11. Detection of the Single-Session Complete Ablation Rate by Contrast-Enhanced Ultrasound during Ultrasound-Guided Laser Ablation for Benign Thyroid Nodules: A Prospective Study

    Directory of Open Access Journals (Sweden)

    Shuhua Ma

    2016-01-01

    Full Text Available This study aimed to investigate the single-session complete ablation rate of ultrasound-guided percutaneous laser ablation (LA for benign thyroid nodules. LA was performed in 90 patients with 118 benign thyroid nodules. Contrast-enhanced ultrasound (CEUS was used to evaluate complete nodule ablation one day after ablation. Thyroid nodule volumes, thyroid functions, clinical symptoms and complications were evaluated 1, 3, 6, 12, and 18 months after ablation. Results showed that all benign thyroid nodules successfully underwent LA. The single-session complete ablation rates for nodules with maximum diameters ≤2 cm, 2-3 cm and ≥3 cm were 93.4%, 70.3% and 61.1%, respectively. All nodule volumes significantly decreased than that one day after ablation (P0.05. Three patients had obvious pain during ablation; one (1.1% had recurrent laryngeal nerve injury, but the voice returned to normal within 6 months after treatment. Thus, ultrasound-guided LA can effectively inactivate benign thyroid nodules. LA is a potentially viable minimally invasive treatment that offers good cosmetic effects.

  12. Postoperative lumbar MR imaging with contrast enhancement. Comparison between symptomatic and asymptomatic patients

    International Nuclear Information System (INIS)

    Grane, P.; Tullberg, T.; Rydberg, J.; Lindgren, L.

    1995-01-01

    Contrast-enhanced MR imaging of the spine after surgery for lumbar disk herniation almost always shows pathologic changes. To investigate to what extent these changes are correlated to patients' actual clinical symptoms, we compared the postoperative MR findings in 19 asymptomatic patients with 42 symptomatic patients (43 levels). The asymptomatic patients underwent MR examination one year after surgery. Twenty-six of the symptomatic patients underwent MR one year of less after surgery, and in 16 patients (17 levels) MR was performed more than one year after surgery. Sixteen percent of the asymptomatic and 42% of the symptomatic patients had disk herniation at the level of previous surgery. Most of the herniated disks were found in the symptomatic patients less than one year after surgery. The amount of epidural scar tissue, displacement and thickening of nerve roots, and compression of the dural sac were also studied. Disk herniation as a probable cause of recurrent sciatica was a common finding among symptomatic patients examined one year or less after surgery. In comparing asymptomatic patients and symptomatic patients with more than one year between surgery and MR examination, no significant radiologic differences, including disk herniation, were found. (orig.)

  13. Postoperative lumbar MR imaging with contrast enhancement. Comparison between symptomatic and asymptomatic patients

    Energy Technology Data Exchange (ETDEWEB)

    Grane, P. [Dept. of Neuroradiology, Karolinska Hospital, Stockholm (Sweden); Tullberg, T. [Dept. of Orthopaedics, St. Goeran`s Hospital, Stockholm (Sweden); Rydberg, J. [Dept. of Radiology, St. Goeran`s Hospital, Stockholm (Sweden); Lindgren, L. [Dept. of Neurosurgery, Karolinska Hospital, Stockholm (Sweden)

    1995-05-01

    Contrast-enhanced MR imaging of the spine after surgery for lumbar disk herniation almost always shows pathologic changes. To investigate to what extent these changes are correlated to patients` actual clinical symptoms, we compared the postoperative MR findings in 19 asymptomatic patients with 42 symptomatic patients (43 levels). The asymptomatic patients underwent MR examination one year after surgery. Twenty-six of the symptomatic patients underwent MR one year of less after surgery, and in 16 patients (17 levels) MR was performed more than one year after surgery. Sixteen percent of the asymptomatic and 42% of the symptomatic patients had disk herniation at the level of previous surgery. Most of the herniated disks were found in the symptomatic patients less than one year after surgery. The amount of epidural scar tissue, displacement and thickening of nerve roots, and compression of the dural sac were also studied. Disk herniation as a probable cause of recurrent sciatica was a common finding among symptomatic patients examined one year or less after surgery. In comparing asymptomatic patients and symptomatic patients with more than one year between surgery and MR examination, no significant radiologic differences, including disk herniation, were found. (orig.).

  14. Contrast enhanced magnetic resonance imaging of the brain using gadolinium-DTPA

    International Nuclear Information System (INIS)

    Valk, J.; Slegte, R.G.M. de; Crezee, F.C.; Hazenberg, G.J.; Thjaha, S.I.; Nauta, J.J.P.; Vrije Univ., Amsterdam; Vrije Univ., Amsterdam; Vrije Univ., Amsterdam

    1987-01-01

    This report concerns a clinical trial with gadolinium-DTPA (Gd-DTPA) as an intravenous contrast medium for magnetic resonance imaging (MRI) in patients with disorders of the central nervous system. Fifty patients, 30 females and 20 males, were examined without and with Gd-GTPA. The contrast medium was well tolerated by all patients. The results of MRI scanning without and with Gd-DTPA and those obtained with computed tomography (CT) using intravenous contrast enhancement were compared. This investigation comprised mainly patients with intracranial tumors, multiple sclerosis, and nasopharyngeal tumors. The results may be summarized as follows: 1) MRI with Gd-DTPA (MRI+) gave better results than MRI without Gd as regards delineation of the lesion, blood vessels and edema in cerebral tumors, pituitary adenomas and acute forms of multiple sclerosis (MS). MRI+ was better than CT in 32 of the 50 cases examined; with intracerebral tumors it was better in 15 out of 18 cases. 3) MRI+ was always better than CT in patients with MS. In 3 out of 7 cases MRI demonstrated the acute MS lesions. 4) MRI+ seemed to have advantages also in nasopharyngeal tumors as ascertained from this limited experience. (orig.)

  15. Dynamic contrast-enhanced MR imaging to assess physiologic variations of myometrial perfusion

    International Nuclear Information System (INIS)

    Thomassin-Naggara, Isabelle; Balvay, Daniel; Cuenod, Charles A.; Darai, Emile; Marsault, Claude; Bazot, Marc

    2010-01-01

    To prospectively evaluate the ability of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) to assess physiological microvascular states in normal myometrium. Eighty-five women (62 women of reproductive age, 23 postmenopausal) undergoing DCE-MRI of the pelvis were included. Microvascular parameters for the inner and outer myometrium were analysed using a pharmacokinetic model. These parameters were tissue blood flow (F), blood volume fraction (V b ), permeability-surface area product (PS), interstitial volume fraction (V e ) and lag time (Dt). In the women of reproductive age, the inner myometrium displayed higher F and PS, lower V b and V e , and longer Dt than the outer myometrium (p = 0.02, p = 0.01, p = 0.005, p = 0.03 and p = 0.01, respectively). The inner myometrium presented microvascular variations during the menstrual cycle with a pre-ovulatory peak followed by a fall reaching a nadir of F and V b about 4 days after ovulation. Compared with women of reproductive age, in the postmenopausal state, F and V b decreased in the outer myometrium, while PS, V e and Dt increased (p < 0.0001, p = 0.001, p = 0.001, p = 0.03 and p = 0.0004, respectively). DCE-MRI is a non-invasive technique that can measure variations of myometrial microcirculation, and thereby be potentially useful to help characterize the role and states of the myometrium in assisted reproductive therapy. (orig.)

  16. Assessment of Hypoxia in Human Cervical Carcinoma Xenografts by Dynamic Contrast-Enhanced Magnetic Resonance Imaging

    International Nuclear Information System (INIS)

    Ellingsen, Christine; Egeland, Tormod A.M.; Gulliksrud, Kristine M.Sc.; Gaustad, Jon-Vidar; Mathiesen, Berit; Rofstad, Einar K.

    2009-01-01

    Purpose: Patients with advanced cervical cancer and highly hypoxic primary tumors show increased frequency of locoregional treatment failure and poor disease-free and overall survival rates. The potential usefulness of gadolinium-diethylenetriaminepentaacetic acid (Gd-DTPA)-based dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in assessing tumor hypoxia noninvasively was investigated in the present preclinical study. Methods and Materials: CK-160 and TS-415 human cervical carcinoma xenografts transplanted intramuscularly (i.m.) or subcutaneously (s.c.) in BALB/c nu/nu mice were subjected to DCE-MRI and measurement of fraction of radiobiologically hypoxic cells. Tumor images of K trans (the volume transfer constant of Gd-DTPA) and v e (the extracellular volume fraction of the imaged tissue) were produced by pharmacokinetic analysis of the DCE-MRI data. Fraction of radiobiologically hypoxic cells was measured by using the paired survival curve method. Results: Fraction of radiobiologically hypoxic cells differed significantly among the four tumor groups. The mean values ± SE were determined to be 44% ± 7% (i.m. CK-160), 77% ± 10% (s.c. CK-160), 23% ± 5% (i.m. TS-415), and 52% ± 6% (s.c. TS-415). The four tumor groups differed significantly also in K trans , and there was an unambiguous inverse relationship between K trans and fraction of radiobiologically hypoxic cells. On the other hand, significant differences among the groups in v e could not be detected. Conclusions: The study supports the clinical development of DCE-MRI as a method for assessing the extent of hypoxia in carcinoma of the cervix

  17. Evaluation of articular cartilage degeneration with contrast-enhanced magnetic resonance imaging

    International Nuclear Information System (INIS)

    Fujioka, Mikihiro

    1994-01-01

    The evaluation of glycosaminoglycan (GAG) concentration is important in the clinical diagnosis of articular cartilage degeneration. Glycosaminoglycan provides a large number of fixed negative charges. When manganese ion (Mn 2+ ) is administered to the cartilage matrix, this cation diffuses into the matrix and accumulates in accordance with the distribution of fixed negative charges owing to the electrostatic interaction. The accumulation of Mn 2+ causes a shortening of the relaxation times, resulting in high signal intensity in the MR image, when a T 1 -weighted image is obtained. The present study applied this new method to the articular cartilage to evaluate the degree of the cartilage degeneration. Small pieces of articular cartilage were dissected from the knee joints of young chickens. Experimentally degenerated articular cartilage was obtained by treating the specimen with various concentrations of papain solution. Then specimens were soaked in manganese solution until they obtained equilibrium and served for MR microimaging. The fixed charge density (FCD), the concentration of Mn 2+ and Na + , T 1 and T 2 relaxation times were also measured. In degenerated cartilage, lower accumulation of Mn 2+ due to lower GAG density caused a lower than normal signal intensity. Thus, administration of Mn 2+ enhances the biochemical change in the cartilage matrix in terms of differences in the relaxation time. The actual signal intensity on MRI of each specimen corresponded to the theoretical signal intensity, which was calculated from the FCD. It was concluded that MR images taken with contrast enhancement by Mn 2+ give direct visual information about the GAG density in the articular cartilage. MRI with cationic contrast agent could develop into a new method for early non-invasive diagnosis of cartilage dysfunction and degeneration. (author)

  18. Contrast-enhanced turbo spin-echo(TSE) T1-weighted imaging: improved contrast of enhancing lesions

    International Nuclear Information System (INIS)

    Choi, Sung Wook; Lee, Ghi Jai; Shim, Jae Chan; Lee, Young Ju; Jeong, Se Hyung; Kim, Ho kyun

    1997-01-01

    The purpose of this study was to evaluate the effect of contrast improvement of enhancing brain lesions by inherent magnetization transfer effect in turbo spin-echo(TSE)T1-weighted MR imaging. Twenty-six enhancing lesions of 19 patients were included in this study. Using a 1.0T superconductive MR unit, contrast-enhanced SE T1-weighted images(TR=3D600 msec, TE=3D12 msec, NEX=3D2, acquistition time=3D4min 27sec) and contrast-enhanced TSE T1-weighted images(TR=3D600 msec, TE=3D12, acquistition time=3D1min 44sec) were obtained. Signal intensities at enhancing lesions and adjacent white matter were measured in the same regions of both images. Signal-to-noise ratio(SNR) of enhancing lesions and adjacent white matter, and con-trast-to-noise ratio(CNR) and lesion-to-background contrast (LBC) of enhancing lesions were calculated and statistically analysed using the paired t-test. On contrast-enhanced TSE T1-weighted images, SNR of enhancing lesions and adjacent white matter decreased by 18%(p<0.01) and 32%(p<0.01), respectively, compared to contrast-enhanced SE T1-weighted images. CNR and LBC of enhancing lesions increased by 16%(p<0.05) and 66%(p<0.01), respectively. Due to the proposed inherent magnetization transfer effects in TSE imaging, con-trast-enhanced T1-weighted TSE images demonstrated a statistically significant improvement in CNR and LBC, compared to conventional contrast-enhanced T1-weighted SE images, and scan time was much shorter

  19. General Ultrasound Imaging

    Medline Plus

    Full Text Available ... and treat medical conditions. Conventional ultrasound displays the images in thin, flat sections of the body. Advancements in ultrasound technology include three-dimensional (3- ...

  20. Perfusion magnetic resonance imaging and magnetic resonance spectroscopy of cerebral gliomas showing imperceptible contrast enhancement on conventional magnetic resonance imaging

    International Nuclear Information System (INIS)

    Batra, A.; Tripathi, R.P.; Singh, A.K.

    2004-01-01

    The purpose of the present paper was to evaluate the utility of perfusion MRI in cerebral gliomas showing imperceptible contrast enhancement on conventional MRI, and to evaluate the relationships of perfusion MRI and magnetic resonance (MR) spectroscopic results in these tumours. Twenty-two patients with histopathologically proven cerebral gliomas and showing insignificant contrast enhancement on conventional MR were included in the present study. All patients underwent perfusion MRI and MR spectroscopy on a 1.5-T MR system. Significant differences of the relative cerebral blood volume (rCBV) values and the choline : creatine ratios were noted between low-grade and anaplastic gliomas (P < 0.01). Good correlation was found between the rCBV values and the choline : creatine values (y = 0. 532x + 1.5643; r = 0.67). Perfusion MRI can be a useful tool in assessing the histopathological grade of non-contrast-enhancing cerebral gliomas. Along with MR spectroscopic imaging it can serve as an important technique for preoperative characterization of such gliomas, so that accurate targeting by stereotactic biopsies is possible. Copyright (2004) Blackwell Science Pty Ltd

  1. Assessment of Tumor Radioresponsiveness and Metastatic Potential by Dynamic Contrast-Enhanced Magnetic Resonance Imaging

    International Nuclear Information System (INIS)

    Ovrebo, Kirsti Marie; Gulliksrud, Kristine; Mathiesen, Berit; Rofstad, Einar K.

    2011-01-01

    Purpose: It has been suggested that gadolinium diethylene-triamine penta-acetic acid (Gd-DTPA)-based dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) may provide clinically useful biomarkers for personalized cancer treatment. In this preclinical study, we investigated the potential of DCE-MRI as a noninvasive method for assessing the radioresponsiveness and metastatic potential of tumors. Methods and Materials: R-18 melanoma xenografts growing in BALB/c nu/nu mice were used as experimental tumor models. Fifty tumors were subjected to DCE-MRI, and parametric images of K trans (the volume transfer constant of Gd-DTPA) and v e (the fractional distribution volume of Gd-DTPA) were produced by pharmacokinetic analysis of the DCE-MRI series. The tumors were irradiated after the DCE-MRI, either with a single dose of 10 Gy for detection of radiobiological hypoxia (30 tumors) or with five fractions of 4 Gy in 48 h for assessment of radioresponsiveness (20 tumors). The host mice were then euthanized and examined for lymph node metastases, and the primary tumors were resected for measurement of cell survival in vitro. Results: Tumors with hypoxic cells showed significantly lower K trans values than tumors without significant hypoxia (p trans decreased with increasing cell surviving fraction for tumors given fractionated radiation treatment (p trans values than tumors in metastasis-negative mice (p e and tumor hypoxia, radioresponsiveness, or metastatic potential could not be detected. Conclusions: R-18 tumors with low K trans values are likely to be resistant to radiation treatment and have a high probability of developing lymph node metastases. The general validity of these observations should be investigated further by studying preclinical tumor models with biological properties different from those of the R-18 tumors.

  2. Comparison of liver volumetry on contrast-enhanced CT images: one semiautomatic and two automatic approaches.

    Science.gov (United States)

    Cai, Wei; He, Baochun; Fan, Yingfang; Fang, Chihua; Jia, Fucang

    2016-11-08

    This study was to evaluate the accuracy, consistency, and efficiency of three liver volumetry methods- one interactive method, an in-house-developed 3D medical Image Analysis (3DMIA) system, one automatic active shape model (ASM)-based segmentation, and one automatic probabilistic atlas (PA)-guided segmentation method on clinical contrast-enhanced CT images. Forty-two datasets, including 27 normal liver and 15 space-occupying liver lesion patients, were retrospectively included in this study. The three methods - one semiautomatic 3DMIA, one automatic ASM-based, and one automatic PA-based liver volumetry - achieved an accuracy with VD (volume difference) of -1.69%, -2.75%, and 3.06% in the normal group, respectively, and with VD of -3.20%, -3.35%, and 4.14% in the space-occupying lesion group, respectively. However, the three methods achieved an efficiency of 27.63 mins, 1.26 mins, 1.18 mins on average, respectively, compared with the manual volumetry, which took 43.98 mins. The high intraclass correlation coefficient between the three methods and the manual method indicated an excel-lent agreement on liver volumetry. Significant differences in segmentation time were observed between the three methods (3DMIA, ASM, and PA) and the manual volumetry (p volumetries (ASM and PA) and the semiautomatic volumetry (3DMIA) (p < 0.001). The semiautomatic interactive 3DMIA, automatic ASM-based, and automatic PA-based liver volum-etry agreed well with manual gold standard in both the normal liver group and the space-occupying lesion group. The ASM- and PA-based automatic segmentation have better efficiency in clinical use. © 2016 The Authors.

  3. General Ultrasound Imaging

    Medline Plus

    Full Text Available ... ultrasound. top of page How does the procedure work? Ultrasound imaging is based on the same principles ... modality for the diagnosis and monitoring of pregnant women and their unborn babies. Ultrasound provides real-time ...

  4. General Ultrasound Imaging

    Medline Plus

    Full Text Available ... medical test that helps physicians diagnose and treat medical conditions. Conventional ultrasound displays the images in thin, flat sections of the body. Advancements in ultrasound technology include three-dimensional (3-D) ultrasound that formats ...

  5. General Ultrasound Imaging

    Medline Plus

    Full Text Available ... D images. A Doppler ultrasound study may be part of an ultrasound examination. Doppler ultrasound , also called ... terms of the distance traveled per unit of time, rather than as a color picture. It can ...

  6. Unusual presentation of a pancreatic insulinoma in helical CT and dynamic contrast-enhanced MR imaging: case report

    Energy Technology Data Exchange (ETDEWEB)

    Iglesias, A.; Arias, M.; Brasa, J. [Unidad de Resonancia Magnetica (Medtec), Hospital Xeral-Cies, Vigo (Spain); Casal, M. [Unidad de Radiologia Intervencionista, Hospital Xeral-Cies, Vigo (Spain); Paramo, C. [Servicio de Endocrinologia, Hospital Xeral-Cies, Vigo (Spain); Fiano, C. [Servicio de Anatomia Patologica, Hospital Xeral-Cies, Vigo (Spain)

    2001-06-01

    Insulinomas are pancreatic neoplasms that can be radiologically characterized typically because of their tendency to present intense and early contrast enhancement with a wash-out phenomenon. In this sense, we report an unusual case of a hypovascular solid pancreatic insulinoma confirmed with surgery and pathologic analysis, in a patient with normal serum insulin levels. In the two-phase helical CT, the mass behaved as a hypodense lesion with respect to the surrounding pancreatic parenchyma during the arterial phase and as a hypointense lesion during the dynamic contrast-enhanced MR imaging. Pathologic examination demonstrated a hypercellular tumor with poor vascularization of intervening stroma which showed prominent amyloid deposits. (orig.)

  7. Unusual presentation of a pancreatic insulinoma in helical CT and dynamic contrast-enhanced MR imaging: case report

    International Nuclear Information System (INIS)

    Iglesias, A.; Arias, M.; Brasa, J.; Casal, M.; Paramo, C.; Fiano, C.

    2001-01-01

    Insulinomas are pancreatic neoplasms that can be radiologically characterized typically because of their tendency to present intense and early contrast enhancement with a wash-out phenomenon. In this sense, we report an unusual case of a hypovascular solid pancreatic insulinoma confirmed with surgery and pathologic analysis, in a patient with normal serum insulin levels. In the two-phase helical CT, the mass behaved as a hypodense lesion with respect to the surrounding pancreatic parenchyma during the arterial phase and as a hypointense lesion during the dynamic contrast-enhanced MR imaging. Pathologic examination demonstrated a hypercellular tumor with poor vascularization of intervening stroma which showed prominent amyloid deposits. (orig.)

  8. Assessment of the link between quantitative biexponential diffusion-weighted imaging and contrast-enhanced MRI in the liver

    NARCIS (Netherlands)

    Dijkstra, Hildebrand; Oudkerk, Matthijs; Kappert, Peter; Sijens, Paul E.

    Purpose: To investigate if intravoxel incoherent motion (IVIM) modeled diffusion-weighted imaging (DWI) can be linked to contrast-enhanced (CE-)MRI in liver parenchyma and liver lesions. Methods: Twenty-five patients underwent IVIM-DWI followed by multiphase CE-MRI using Gd-EOB-DTPA (n = 20) or

  9. Assessment of image display of contrast enhanced T1W images with fat suppression

    International Nuclear Information System (INIS)

    Miyazaki, Isao; Ishizaki, Keiko; Kobayashi, Kuninori; Katou, Masanobu

    2006-01-01

    The effects of imaging conditions and measures for their improvement were examined with regard to recognition of the effects of contrast on images when T 1 -weighted imaging with selective fat suppression was applied. Luminance at the target region was examined before and after contrast imaging using phantoms assuming pre- and post-imaging conditions. A clinical examination was performed on tumors revealed by breast examination, including those surrounded by mammary gland and by fat tissue. When fat suppression was used and imaging contrast was enhanced, the luminance level of fat tumors with the same structure as the prepared phantoms appeared to be high both before and after contrast imaging, and the effects of contrast were not distinguishable. This observation is attributable to the fact that the imaging conditions before and after contrast imaging were substantially different. To make a comparison between pre- and post-contrast images, it is considered necessary to perform imaging with fixed receiver gain and to apply the same imaging method for pre- and post-contrast images by adjusting post-contrast imaging conditions to those of pre-contrast imaging. (author)

  10. Dynamic contrast-enhanced MR imaging to assess physiologic variations of myometrial perfusion

    Energy Technology Data Exchange (ETDEWEB)

    Thomassin-Naggara, Isabelle [Assistance Publique-Hopitaux de Paris, Department of Radiology, Hopital Tenon, Paris (France); Universite Rene Descartes, Laboratoire de Recherche en Imagerie-INSERM U970, Paris (France); Hopital Tenon, Service de Radiologie, Paris (France); Balvay, Daniel [Universite Rene Descartes, Laboratoire de Recherche en Imagerie-INSERM U970, Paris (France); Cuenod, Charles A. [Universite Rene Descartes, Laboratoire de Recherche en Imagerie-INSERM U970, Paris (France); Hopital Europeen Georges Pompidou (HEGP), Department of Radiology, Paris (France); Darai, Emile [Assistance Publique-Hopitaux de Paris, Department of Gynaecology-Obstetrics, Hopital Tenon, Paris (France); Marsault, Claude; Bazot, Marc [Assistance Publique-Hopitaux de Paris, Department of Radiology, Hopital Tenon, Paris (France)

    2010-04-15

    To prospectively evaluate the ability of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) to assess physiological microvascular states in normal myometrium. Eighty-five women (62 women of reproductive age, 23 postmenopausal) undergoing DCE-MRI of the pelvis were included. Microvascular parameters for the inner and outer myometrium were analysed using a pharmacokinetic model. These parameters were tissue blood flow (F), blood volume fraction (V{sub b}), permeability-surface area product (PS), interstitial volume fraction (V{sub e}) and lag time (Dt). In the women of reproductive age, the inner myometrium displayed higher F and PS, lower V{sub b} and V{sub e}, and longer Dt than the outer myometrium (p = 0.02, p = 0.01, p = 0.005, p = 0.03 and p = 0.01, respectively). The inner myometrium presented microvascular variations during the menstrual cycle with a pre-ovulatory peak followed by a fall reaching a nadir of F and V{sub b} about 4 days after ovulation. Compared with women of reproductive age, in the postmenopausal state, F and V{sub b} decreased in the outer myometrium, while PS, V{sub e} and Dt increased (p < 0.0001, p = 0.001, p = 0.001, p = 0.03 and p = 0.0004, respectively). DCE-MRI is a non-invasive technique that can measure variations of myometrial microcirculation, and thereby be potentially useful to help characterize the role and states of the myometrium in assisted reproductive therapy. (orig.)

  11. Dynamic contrast-enhanced MR imaging in osteoid osteoma: relationships with clinical and CT characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Pottecher, P. [Hopital Lariboisiere, AP-HP, Department of Osteoarticular Radiology, Paris (France); Hopital du Bocage, Department of Vascular, Oncologic and Interventional Radiology, Dijon (France); Sibileau, E.; Hamze, B.; Parlier, C.; Laredo, J.D.; Bousson, V. [Hopital Lariboisiere, AP-HP, Department of Osteoarticular Radiology, Paris (France); Aho, S. [Hopital du Bocage, Hospital Hygiene and Epidemiology unit, Dijon (France)

    2017-07-15

    To correlate dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) features to clinical and computed tomography (CT) morphological features of osteoid osteoma (OO). Our institutional review board approved this retrospective study, waiving the need for informed consent. We included the 102 patients treated with interstitial laser ablation for histologically documented OO at our institution in 2008-2013. DCE-MRI variables were the time-enhancement pattern and rising slope (Slope{sub rise}) and CT variables were the bone and segment involved (OO{sub bone} and OO{sub segment,} respectively), OO location relative to the native cortex (OO{sub cortex}), nidus surface area, vessel sign, and largest neighboring-vessel diameter (Dmax{sub vessel}). Descriptive statistics and correlations linking DCE-MRI findings to clinical and CT characteristics were computed. DCE-MRI showed early arterial peak enhancement in 95 (93%) cases, with a mean Slope{sub rise} of 9.30 ± 8.10. CT visualized a vessel sign in 84 (82%) cases with a mean Dmax{sub vessel} of 1.10 ± 0.60 mm. By univariate analysis, Slope{sub rise} correlated significantly with pain duration and Dmax{sub vessel} (r = 0.30, P = 0.003; and r = 0.22, P = 0.03; respectively). Analysis of variance showed that Slope{sub rise} correlated significantly with OO{sub bone} (P < 0.001), with a steeper slope for OOs located in short or flat bones. This study suggests more abundant vascularization of OOs with long-lasting pain and location on short or flat bones. (orig.)

  12. General Ultrasound Imaging

    Medline Plus

    Full Text Available ... Imaging? Ultrasound waves are disrupted by air or gas; therefore ultrasound is not an ideal imaging technique ... with caption Pediatric Content Some imaging tests and treatments have special pediatric considerations. The teddy bear denotes ...

  13. Standardization of dynamic contrast-enhanced ultrasound for the evaluation of antiangiogenic therapies: the French multicenter Support for Innovative and Expensive Techniques Study.

    Science.gov (United States)

    Lassau, Nathalie; Chapotot, Louis; Benatsou, Baya; Vilgrain, Valérie; Kind, Michèle; Lacroix, Joëlle; Cuinet, Marie; Taieb, Sophie; Aziza, Richard; Sarran, Antony; Labbe, Catherine; Gallix, Benoît; Lucidarme, Olivier; Ptak, Yvette; Rocher, Laurence; Caquot, Louis Michel; Chagnon, Sophie; Marion, Denis; Luciani, Alain; Uzan-Augui, Joëlle; Koscielny, Serge

    2012-12-01

    The objectives of this study are to describe the standardization and dissemination of dynamic contrast-enhanced ultrasound (DCE-US) for the evaluation of antiangiogenic treatments in solid tumors across 19 oncology centers in France and to define a quality score to account for the variability of the evaluation criteria used to collect DCE-US data. This prospective Soutien aux Techniques Innovantes Coûteuses (Support for Innovative and Expensive Techniques) DCE-US study included patients with metastatic breast cancer, melanoma, colon cancer, gastrointestinal stromal tumors, renal cell carcinoma and patients with primary hepatocellular carcinoma tumors treated with antiangiogenic therapy. The DCE-US method was made available across 19 oncology centers in France. Overall, 2339 DCE-US examinations were performed by 65 radiologists in 539 patients.One target site per patient was studied. Standardized DCE-US examinations were performed before treatment (day 0) and at days 7, 15, 30, and 60. Dynamic contrast-enhanced ultrasound data were transferred from the different sites to the main study center at the Institut Gustave-Roussy for analysis. Quantitative analyses were performed with a mathematical model to determine 7 DCE-US functional parameters using raw linear data. Radiologists had to evaluate 6 criteria that were potentially linked to the precision of the evaluation of these parameters: lesion size, target motion, loss of target, clear borders, total acquisition of wash-in, and vascular recognition imaging window adapted to the lesion size.Eighteen DCE-US examinations were randomly selected from the Soutien aux Techniques Innovantes Coûteuses (Support for Innovative and Expensive Techniques) database. Each examination was quantified twice by 8 engineers/radiologists trained to evaluate the perfusion parameters. The intraobserver variability was estimated on the basis of differences between examinations performed by the same radiologist. The mean coefficient of

  14. Ingestible roasted barley for contrast-enhanced photoacoustic imaging in animal and human subjects.

    Science.gov (United States)

    Wang, Depeng; Lee, Dong Hyeun; Huang, Haoyuan; Vu, Tri; Lim, Rachel Su Ann; Nyayapathi, Nikhila; Chitgupi, Upendra; Liu, Maggie; Geng, Jumin; Xia, Jun; Lovell, Jonathan F

    2018-08-01

    Photoacoustic computed tomography (PACT) is an emerging imaging modality. While many contrast agents have been developed for PACT, these typically cannot immediately be used in humans due to the lengthy regulatory process. We screened two hundred types of ingestible foodstuff samples for photoacoustic contrast with 1064 nm pulse laser excitation, and identified roasted barley as a promising candidate. Twenty brands of roasted barley were further screened to identify the one with the strongest contrast, presumably based on complex chemical modifications incurred during the roasting process. Individual roasted barley particles could be detected through 3.5 cm of chicken-breast tissue and through the whole hand of healthy human volunteers. With PACT, but not ultrasound imaging, a single grain of roasted barley was detected in a field of hundreds of non-roasted particles. Upon oral administration, roasted barley enabled imaging of the gut and peristalsis in mice. Prepared roasted barley tea could be detected through 2.5 cm chicken breast tissue. When barley tea was administered to humans, photoacoustic imaging visualized swallowing dynamics in healthy volunteers. Thus, roasted barley represents an edible foodstuff that should be considered for photoacoustic contrast imaging of swallowing and gut processes, with immediate potential for clinical translation. Copyright © 2018 Elsevier Ltd. All rights reserved.

  15. Age-related differences in skeletal muscle microvascular response to exercise as detected by contrast-enhanced ultrasound (CEUS).

    Science.gov (United States)

    Hildebrandt, Wulf; Schwarzbach, Hans; Pardun, Anita; Hannemann, Lena; Bogs, Björn; König, Alexander M; Mahnken, Andreas H; Hildebrandt, Olaf; Koehler, Ulrich; Kinscherf, Ralf

    2017-01-01

    Aging involves reductions in exercise total limb blood flow and exercise capacity. We hypothesized that this may involve early age-related impairments of skeletal muscle microvascular responsiveness as previously reported for insulin but not for exercise stimuli in humans. Using an isometric exercise model, we studied the effect of age on contrast-enhanced ultrasound (CEUS) parameters, i.e. microvascular blood volume (MBV), flow velocity (MFV) and blood flow (MBF) calculated from replenishment of Sonovue contrast-agent microbubbles after their destruction. CEUS was applied to the vastus lateralis (VLat) and intermedius (VInt) muscle in 15 middle-aged (MA, 43.6±1.5 years) and 11 young (YG, 24.1±0.6 years) healthy males before, during, and after 2 min of isometric knee extension at 15% of peak torque (PT). In addition, total leg blood flow as recorded by femoral artery Doppler-flow. Moreover, fiber-type-specific and overall capillarisation as well as fiber composition were additionally assessed in Vlat biopsies obtained from CEUS site. MA and YG had similar quadriceps muscle MRT-volume or PT and maximal oxygen uptake as well as a normal cardiovascular risk factors and intima-media-thickness. During isometric exercise MA compared to YG reached significantly lower levels in MFV (0.123±0.016 vs. 0.208±0.036 a.u.) and MBF (0.007±0.001 vs. 0.012±0.002 a.u.). In the VInt the (post-occlusive hyperemia) post-exercise peaks in MBV and MBF were significantly lower in MA vs. YG. Capillary density, capillary fiber contacts and femoral artery Doppler were similar between MA and YG. In the absence of significant age-related reductions in capillarisation, total leg blood flow or muscle mass, healthy middle-aged males reveal impaired skeletal muscle microcirculatory responses to isometric exercise. Whether this limits isometric muscle performance remains to be assessed.

  16. Age-related differences in skeletal muscle microvascular response to exercise as detected by contrast-enhanced ultrasound (CEUS.

    Directory of Open Access Journals (Sweden)

    Wulf Hildebrandt

    Full Text Available Aging involves reductions in exercise total limb blood flow and exercise capacity. We hypothesized that this may involve early age-related impairments of skeletal muscle microvascular responsiveness as previously reported for insulin but not for exercise stimuli in humans.Using an isometric exercise model, we studied the effect of age on contrast-enhanced ultrasound (CEUS parameters, i.e. microvascular blood volume (MBV, flow velocity (MFV and blood flow (MBF calculated from replenishment of Sonovue contrast-agent microbubbles after their destruction. CEUS was applied to the vastus lateralis (VLat and intermedius (VInt muscle in 15 middle-aged (MA, 43.6±1.5 years and 11 young (YG, 24.1±0.6 years healthy males before, during, and after 2 min of isometric knee extension at 15% of peak torque (PT. In addition, total leg blood flow as recorded by femoral artery Doppler-flow. Moreover, fiber-type-specific and overall capillarisation as well as fiber composition were additionally assessed in Vlat biopsies obtained from CEUS site. MA and YG had similar quadriceps muscle MRT-volume or PT and maximal oxygen uptake as well as a normal cardiovascular risk factors and intima-media-thickness.During isometric exercise MA compared to YG reached significantly lower levels in MFV (0.123±0.016 vs. 0.208±0.036 a.u. and MBF (0.007±0.001 vs. 0.012±0.002 a.u.. In the VInt the (post-occlusive hyperemia post-exercise peaks in MBV and MBF were significantly lower in MA vs. YG. Capillary density, capillary fiber contacts and femoral artery Doppler were similar between MA and YG.In the absence of significant age-related reductions in capillarisation, total leg blood flow or muscle mass, healthy middle-aged males reveal impaired skeletal muscle microcirculatory responses to isometric exercise. Whether this limits isometric muscle performance remains to be assessed.

  17. Subendometrial enhancement and peritumoral enhancement for assessing endometrial cancer on dynamic contrast enhanced MR imaging

    International Nuclear Information System (INIS)

    Fujii, Shinya; Kido, Aki; Baba, Tsukasa; Fujimoto, Koji; Daido, Sayaka; Matsumura, Noriomi; Konishi, Ikuo; Togashi, Kaori

    2015-01-01

    Highlights: •We have assessed the peritumoral enhancement (PTE), which mimics SEE on DCE. •We evaluated the diagnostic accuracy of SEE for the myometrial invasion and the frequency of PTE. •We assessed the relationship between these enhancements and important pathologic factors. •PTE Type 1 is the main factor causing the overestimation of myometrial invasion using SEE on DCE. •PTE Type 2 correlates the myometrial invasion and may play an important role in the diagnosis of LVSI. -- Abstract: Objectives: To evaluate the diagnostic accuracy of subendometrial enhancement (SEE) in assessing the myometrial invasion in endometrial cancer, the frequency and clinical significance of peritumoral enhancement (PTE) on dynamic contrast enhanced (DCE) imaging. Materials and methods: MR images of 147 patients with endometrial cancer were retrospectively analyzed for intact SEE and PTEs: Type 1, a focal early enhancement peritumorally, and Type 2, an irregular thin-layered early intense enhancement peritumorally. Two radiologists independently assessed intact SEE and PTEs on DCE imaging and compared the lesions by the presence and depth of myometrial invasion, grade, lymphovascular space involvement (LVSI), and lymph node metastasis. The relationship between SEE, PTEs, and each factor was analyzed using univariate and multivariate analyses. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy were calculated for SEE. Results: The sensitivity, specificity, PPV, NPV and diagnostic accuracy for myometrial invasion based on SEE disruption on DCE were 96.6%, 32.1–46.4%, 85.8–88.5%, 69.2–76.5%, and 84.4–87.1%. According to multivariate analysis, SEE significantly predicted myometrial invasion (p < 0.0001). PTE Type 2 significantly predicted myometrial invasion presence (p < 0.05) and depth (p < 0.01). Conclusion: Diagnosis of myometrial invasion only by using SEE might be difficult on DCE-MRI due to the

  18. Subendometrial enhancement and peritumoral enhancement for assessing endometrial cancer on dynamic contrast enhanced MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Fujii, Shinya [Division of Radiology, Department of Pathophysiological and Therapeutic Science, Faculty of Medicine, Tottori University, Yonago (Japan); Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, Kyoto (Japan); Kido, Aki, E-mail: akikido@kuhp.kyoto-u.ac.jp [Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, Kyoto (Japan); Baba, Tsukasa [Departments of Gynecology and Obstetrics, Graduate School of Medicine, Kyoto University, Kyoto (Japan); Fujimoto, Koji; Daido, Sayaka [Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, Kyoto (Japan); Matsumura, Noriomi; Konishi, Ikuo [Departments of Gynecology and Obstetrics, Graduate School of Medicine, Kyoto University, Kyoto (Japan); Togashi, Kaori [Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, Kyoto (Japan)

    2015-04-15

    Highlights: •We have assessed the peritumoral enhancement (PTE), which mimics SEE on DCE. •We evaluated the diagnostic accuracy of SEE for the myometrial invasion and the frequency of PTE. •We assessed the relationship between these enhancements and important pathologic factors. •PTE Type 1 is the main factor causing the overestimation of myometrial invasion using SEE on DCE. •PTE Type 2 correlates the myometrial invasion and may play an important role in the diagnosis of LVSI. -- Abstract: Objectives: To evaluate the diagnostic accuracy of subendometrial enhancement (SEE) in assessing the myometrial invasion in endometrial cancer, the frequency and clinical significance of peritumoral enhancement (PTE) on dynamic contrast enhanced (DCE) imaging. Materials and methods: MR images of 147 patients with endometrial cancer were retrospectively analyzed for intact SEE and PTEs: Type 1, a focal early enhancement peritumorally, and Type 2, an irregular thin-layered early intense enhancement peritumorally. Two radiologists independently assessed intact SEE and PTEs on DCE imaging and compared the lesions by the presence and depth of myometrial invasion, grade, lymphovascular space involvement (LVSI), and lymph node metastasis. The relationship between SEE, PTEs, and each factor was analyzed using univariate and multivariate analyses. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy were calculated for SEE. Results: The sensitivity, specificity, PPV, NPV and diagnostic accuracy for myometrial invasion based on SEE disruption on DCE were 96.6%, 32.1–46.4%, 85.8–88.5%, 69.2–76.5%, and 84.4–87.1%. According to multivariate analysis, SEE significantly predicted myometrial invasion (p < 0.0001). PTE Type 2 significantly predicted myometrial invasion presence (p < 0.05) and depth (p < 0.01). Conclusion: Diagnosis of myometrial invasion only by using SEE might be difficult on DCE-MRI due to the

  19. Cranial nerve assessment in cavernous sinus tumors with contrast-enhanced 3D fast-imaging employing steady-state acquisition MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Amemiya, Shiori; Aoki, Shigeki; Ohtomo, Kuni [University of Tokyo, Department of Radiology, Graduate School of Medicine, Bunkyo-ku, Tokyo (Japan)

    2009-07-15

    The purpose of this study is to apply contrast-enhanced 3D fast-imaging employing steady-state acquisition (3D-FIESTA) imaging to the evaluation of cranial nerves (CN) in patients with cavernous sinus tumors. Contrast-enhanced 3D-FIESTA images were acquired from ten patients with cavernous sinus tumors with a 3-T unit. In all cases, the trigeminal nerve with tumor involvement was easily identified in the cavernous portions. Although oculomotor and abducens nerves were clearly visualized against the tumor area with intense contrast enhancement, they were hardly identifiable within the area lacking contrast enhancement. The trochlear nerve was visualized in part, but not delineated as a linear structure outside of the lesion. Contrast-enhanced 3D-FIESTA can be useful in the assessment of cranial nerves in and around the cavernous sinus with tumor involvement. (orig.)

  20. Cranial nerve assessment in cavernous sinus tumors with contrast-enhanced 3D fast-imaging employing steady-state acquisition MR imaging

    International Nuclear Information System (INIS)

    Amemiya, Shiori; Aoki, Shigeki; Ohtomo, Kuni

    2009-01-01

    The purpose of this study is to apply contrast-enhanced 3D fast-imaging employing steady-state acquisition (3D-FIESTA) imaging to the evaluation of cranial nerves (CN) in patients with cavernous sinus tumors. Contrast-enhanced 3D-FIESTA images were acquired from ten patients with cavernous sinus tumors with a 3-T unit. In all cases, the trigeminal nerve with tumor involvement was easily identified in the cavernous portions. Although oculomotor and abducens nerves were clearly visualized against the tumor area with intense contrast enhancement, they were hardly identifiable within the area lacking contrast enhancement. The trochlear nerve was visualized in part, but not delineated as a linear structure outside of the lesion. Contrast-enhanced 3D-FIESTA can be useful in the assessment of cranial nerves in and around the cavernous sinus with tumor involvement. (orig.)

  1. Development of a dynamic flow imaging phantom for dynamic contrast-enhanced CT

    International Nuclear Information System (INIS)

    Driscoll, B.; Keller, H.; Coolens, C.

    2011-01-01

    Purpose: Dynamic contrast enhanced CT (DCE-CT) studies with modeling of blood flow and tissue perfusion are becoming more prevalent in the clinic, with advances in wide volume CT scanners allowing the imaging of an entire organ with sub-second image frequency and sub-millimeter accuracy. Wide-spread implementation of perfusion DCE-CT, however, is pending fundamental validation of the quantitative parameters that result from dynamic contrast imaging and perfusion modeling. Therefore, the goal of this work was to design and construct a novel dynamic flow imaging phantom capable of producing typical clinical time-attenuation curves (TACs) with the purpose of developing a framework for the quantification and validation of DCE-CT measurements and kinetic modeling under realistic flow conditions. Methods: The phantom is based on a simple two-compartment model and was printed using a 3D printer. Initial analysis of the phantom involved simple flow measurements and progressed to DCE-CT experiments in order to test the phantoms range and reproducibility. The phantom was then utilized to generate realistic input TACs. A phantom prediction model was developed to compute the input and output TACs based on a given set of five experimental (control) parameters: pump flow rate, injection pump flow rate, injection contrast concentration, and both control valve positions. The prediction model is then inversely applied to determine the control parameters necessary to generate a set of desired input and output TACs. A protocol was developed and performed using the phantom to investigate image noise, partial volume effects and CT number accuracy under realistic flow conditionsResults: This phantom and its surrounding flow system are capable of creating a wide range of physiologically relevant TACs, which are reproducible with minimal error between experiments (σ/μ 2 ) for the input function between 0.95 and 0.98, while the maximum enhancement differed by no more than 3.3%. The

  2. Usefulness of combined use of contrast-enhanced ultrasound and TI-RADS classification for the differentiation of benign from malignant lesions of thyroid nodules.

    Science.gov (United States)

    Zhang, Yan; Zhou, Ping; Tian, Shuang-Ming; Zhao, Yong-Feng; Li, Jia-Le; Li, Lan

    2017-04-01

    To study the thyroid image reporting and data system (TI-RADS) classification and the contrast-enhanced ultrasound (CEUS) enhancement pattern of thyroid nodules, and to determine whether combined use of both methods is helpful in the diagnosis of thyroid nodules. A total of 319 thyroid nodules in 246 patients were assessed with TI-RADS, CEUS and a combination of both methods. The diagnostic performance of TI-RADS, CEUS and a combination of both methods was compared. The accuracy in the diagnosis of thyroid nodules was 90.3 % for TI-RADS, 90.0 % for CEUS and 96.0 % for a combination of both methods respectively. A statistically significant difference was not observed in the diagnostic accuracy of CEUS and TI-RADS (P > 0.05). However, a significant difference was observed between a combination of both methods and either alone (P TI-RADS classifications of 4a and 4b thyroid nodules compared with TI-RADS alone (P  0.05). The improved TI-RADS, when combined with CEUS, could significantly improve the diagnostic accuracy for thyroid nodules, especially for TI-RADS class-4 thyroid nodules. • TI-RADS can be used as the primary diagnostic standard for thyroid nodules • CEUS can be used as an important complement to TI-RADS • The improved TI-RADS can significantly improve the qualitative diagnostic accuracy.

  3. Acoustic Radiation Force Impulse Elastography for Efficacy Evaluation after Hepatocellular Carcinoma Radiofrequency Ablation: A Comparative Study with Contrast-Enhanced Ultrasound

    Directory of Open Access Journals (Sweden)

    Xiaohong Xu

    2014-01-01

    Full Text Available Aim. To explore acoustic radiation force impulse (ARFI elastography in assessing residual tumors of hepatocellular carcinoma (HCC after radiofrequency ablation (RFA. Materials and Methods. There were 83 HCC lesions among 72 patients. All patients were examined with ARFI, contrast enhanced ultrasound (CEUS, and CT or MRI. Tumor brightness on virtual touch tissue imaging (VTI and shear wave velocity (SWV were assessed before and approximately one month after RFA. Results. There were 14 residual tumors after RFA. VTI showed that all the tumors were darker after RFA. VTI was not able to distinguish the ablated lesions and the residual tumors. 13 residual tumor lesions were detected by CEUS. All completely ablated nodules had SWV demonstration of x.xx., while with those residual nodules, 6 tumors had x.xx measurement and 8 tumors had measurable SWV. nine lesions with residual tumors occurred in cirrhosis subjects and 5 lesions with residual tumors occurred in fibrosis subjects; there was no residual tumor in the normal liver subjects. Conclusion. VTI technique cannot demonstrate residual tumor post RFA. While SWV measurement of less than x.xx is likely associated with residual tumors, measurement of less than x.xx cannot exclude residual tumors. Liver cirrhosis is associated with decreased chance of a complete ablation.

  4. Acoustic Radiation Force Impulse Elastography for Efficacy Evaluation after Hepatocellular Carcinoma Radiofrequency Ablation: A Comparative Study with Contrast-Enhanced Ultrasound

    Science.gov (United States)

    Xu, Xiaohong; Luo, Liangping; Chen, Jiexin; Wang, Jiexin; Zhou, Honglian; Li, Mingyi; Jin, Zhanqiang; Chen, Nianping; Miao, Huilai; Lin, Manzhou; Dai, Wei; Ahuja, Anil T.; Wang, Yi-Xiang J.

    2014-01-01

    Aim. To explore acoustic radiation force impulse (ARFI) elastography in assessing residual tumors of hepatocellular carcinoma (HCC) after radiofrequency ablation (RFA). Materials and Methods. There were 83 HCC lesions among 72 patients. All patients were examined with ARFI, contrast enhanced ultrasound (CEUS), and CT or MRI. Tumor brightness on virtual touch tissue imaging (VTI) and shear wave velocity (SWV) were assessed before and approximately one month after RFA. Results. There were 14 residual tumors after RFA. VTI showed that all the tumors were darker after RFA. VTI was not able to distinguish the ablated lesions and the residual tumors. 13 residual tumor lesions were detected by CEUS. All completely ablated nodules had SWV demonstration of x.xx., while with those residual nodules, 6 tumors had x.xx measurement and 8 tumors had measurable SWV. nine lesions with residual tumors occurred in cirrhosis subjects and 5 lesions with residual tumors occurred in fibrosis subjects; there was no residual tumor in the normal liver subjects. Conclusion. VTI technique cannot demonstrate residual tumor post RFA. While SWV measurement of less than x.xx is likely associated with residual tumors, measurement of less than x.xx cannot exclude residual tumors. Liver cirrhosis is associated with decreased chance of a complete ablation. PMID:24895624

  5. Data driven analysis of dynamic contrast-enhanced magnetic resonance imaging data in breast cancer diagnosis

    NARCIS (Netherlands)

    Twellmann, T.

    2005-01-01

    In the European Union, breast cancer is the most common type of cancer affecting women. If diagnosed in an early stage, breast cancer has an encouraging cure rate. Thus, early detection of breast cancer continues to be the key for an effective treatment. Recently, Dynamic Contrast-Enhanced Magnetic

  6. The use of contrast-enhanced color doppler ultrasound in the differentiation of retinal detachment from vitreous membrane

    International Nuclear Information System (INIS)

    Han, Sang Suk; Chang, Seung Kook; Yoon, Jung Hee; Lee, Young Joon

    2001-01-01

    To compare the clinical utility of contrast-enhanced color Doppler US in the differentiation of retinal detachment (RD) from vitreous membrane (VM) with that of various conventional US modalities, and to analyze the enhancement patterns in cases showing an enhancement effect. In 32 eyes examined over a recent two-year period, RD (n=14) and VM (n=18) were confirmed by surgery (n=28) or clinical follow-up (n=4). In all cases, gray-scale, color Doppler, and power Doppler US were performed prior to contrast injection, and after the intravenous injection of Levovist (Schering, Berlin) by hand for 30 seconds at a dose of 2.5 g and a concentration of 300 mg/mL via an antecubital vein, contrast-enhanced color Doppler US was performed. At Doppler US, the diagnostic criterion for RD and VM was whether or not color signals were visualized in membranous structures. Diagnostic accuracy was 78% at gray-scale US, 81% at color Doppler US, 59% at power Doppler US, and 97% at contrast-enhanced color Doppler US. The sensitivity of color Doppler US to color signals in RD increased from 57% to 93% after contrast enhancement. The enhancement patterns observed were signal accentuation (n=3), signal extension (n=2), signal addition (n=3), and new signal visualization (n=5). Contrast-enhanced color Doppler US was the most accurate US modality for differentiating RD from VM, showing a significantly increased signal detection rate in RD

  7. Imaging diagnosis--Use of multiphasic contrast-enhanced computed tomography for diagnosis of mesenteric volvulus in a dog.

    Science.gov (United States)

    Chow, Kathleen Ella; Stent, Andrew William; Milne, Marjorie

    2014-01-01

    A 4-year-old German shorthaired pointer presented with collapse and hematochezia. Radiographs showed gas and fluid-distended small intestines and loss of serosal detail. Ultrasound examination showed hypomotile, fluid-distended small intestines, and thrombosed jejunal veins. Multiphasic contrast-enhanced computed tomography was performed and showed a CT "whirl sign," an important but nonspecific sign of intestinal volvulus in human patients. At surgery, the majority of the small intestine was entangled in the volvulus and showed black discoloration. The patient was euthanized. Postmortem evaluation yielded a diagnosis of jejunoileal mesenteric volvulus secondary to a congenital omphalomesenteric duct remnant. © 2013 American College of Veterinary Radiology.

  8. Evaluation of tumor response to intra-arterial chemoembolization of hepatocellular carcinoma: Comparison of contrast-enhanced ultrasound with multiphase computed tomography.

    Science.gov (United States)

    Paul, S B; Dhamija, E; Gamanagatti, S R; Sreenivas, V; Yadav, D P; Jain, S; Shalimar; Acharya, S K

    2017-03-01

    To compare the diagnostic accuracy of contrast-enhanced ultrasound (CEUS) with that of multiphase computed tomography (CT) in the evaluation of tumor response to transarterial chemoembolization (TACE) of hepatocellular carcinoma (HCC). Fifty patients (41 men, 9 women; mean age, 53 years±12.5 [SD]) with a total of 70 HCCs (mean size, 5cm±3 [SD]) were evaluated. Post-TACE therapeutic assessment of HCC was done at 4 weeks. Patients with TACE done earlier and reporting with suspicion for recurrence were also included. Patients with hepatic masses seen on ultrasound were enrolled and subjected to CEUS, multiphase CT and magnetic resonance imaging (MRI). Hyperenhancing area at the tumor site on arterial phase of CEUS/multiphase CT/MRI was termed as residual disease (RD), the patterns of which were described on CEUS. Diagnostic accuracies of CEUS and MPCT were compared to that of MRI that was used as the reference standard. CEUS detected RD in 43/70 HCCs (61%). RD had a heterogeneous pattern in 22/43 HCCs (51%). Sensitivities of CEUS and multiphase CT were 94% (34/36; 95% CI: 81-99%) and 50% (18/36; 95% CI: 33-67%) respectively. Significant difference in sensitivity was found between CEUS and multiphase CT (P=0.0001). CEUS and multiphase CT had 100% specificity (95% CI: 83-100%). CEUS is a useful technique for detecting RD in HCC after TACE. For long term surveillance, CEUS should be complemented with multiphase CT/MRI for a comprehensive evaluation. Copyright © 2016 Éditions françaises de radiologie. Published by Elsevier Masson SAS. All rights reserved.

  9. Hepatocellular carcinoma on MR diffusion weighted imaging and dynamic contrast-enhanced imaging

    International Nuclear Information System (INIS)

    Dong Aisheng; Zuo Changjing; Tian Jianming; Lu Jianping; Wang Jian; Wang Li; Wang Fei

    2009-01-01

    Objective: To evaluate the findings of hepatocellular carcinoma (HCC) on DWI and dynamic Gd-DTPA-enhanced MR imaging. Methods: Eighty one patients with chronic hepatitis or liver cirrhosis underwent both DWI and dynamic Gd-DTPA-enhanced MRI studies of the liver for HCC detection. MR data of were retrospectively analyzed. Two observers determined in consensus the location and the number of focal lesions. The signal manifestation of the lesions on DWI and dynamic Gd-DTPA-enhanced MR imaging were analyzed. Results: DWI and Gd-DTPA-enhanced MR images detected 122 HCCs and 14 benign lesions. One hundred and sixteen HCCs (95.1%) showed hyperintensity on DWI and 6 HCCs in patients with severe cirrhosis showed isointensity. One hundred and five HCCs (86.1%) revealed hypointensity, 11 HCCs (9.0%) showed isointensity and 6 HCCs (4.9%) exhibited hyperintensity on T 1 weighted images. On Gd-DTPA-enhanced MR images, 101 HCCs(82.8%) were significantly enhanced on arterial phase and 99 HCCs showed hypointensity on portal and equilibrium phases. Twenty HCCs (16.4%), 18 of 20 less than 20 mm in diameter, showed isointensity on arterial phase and hyperintensity on DWI. Eight of 14 benign lesions showed hyperintensity and 6 isointensity on DWI. Five benign lesions with hypointensity on T 1 weighted images without contrast and hyperintensity on DWI showed no enhancement on Gd-DTPA-enhanced MR images; 6 benign lesions with isointensity on both T 1 weighted imaging without contrast and DWI exhibited avid enhancement on arterial phase and isointensty on portal and equilibrium phases; one of the two benign lesions, with isointensity before and after contrast images and hyperintentiy on DWI, was a regenerative nodule; another regenerative nodule with hyperintensity on both T 1 weighted images without contrast and DWI was greatly enhanced on arterial phase and showed isointensity on portal and equilibrium phases. Conclusions: Most of the HCCs were greatly enhanced on arterial phase on Gd

  10. Magnetic Resonance Imaging Susceptibility-Weighted Imaging Lesion and Contrast Enhancement May Represent Infectious Intracranial Aneurysm in Infective Endocarditis.

    Science.gov (United States)

    Cho, Sung-Min; Rice, Cory; Marquardt, Robert J; Zhang, Lucy Q; Khoury, Jean; Thatikunta, Prateek; Buletko, Andrew B; Hardman, Julian; Uchino, Ken; Wisco, Dolora

    2017-01-01

    Infectious intracranial aneurysm (IIA) can complicate infective endocarditis (IE). We aimed to describe the magnetic resonance imaging (MRI) characteristics of IIA. We reviewed IIAs among 116 consecutive patients with active IE by conducting a neurological evaluation at a single tertiary referral center from January 2015 to July 2016. MRIs and digital cerebral angiograms (DSA) were reviewed to identify MRI characteristics of IIAs. MRI susceptibility weighted imaging (SWI) was performed to collect data on cerebral microbleeds (CMBs) and sulcal SWI lesions. Out of 116 persons, 74 (63.8%) underwent DSA. IIAs were identified in 13 (17.6% of DSA, 11.2% of entire cohort) and 10 patients with aneurysms underwent MRI with SWI sequence. Nine (90%) out of 10 persons with IIAs had CMB >5 mm or sulcal lesions in SWI (9 in sulci, 6 in parenchyma, and 5 in both). Five out of 8 persons who underwent MRI brain with contrast had enhancement within the SWI lesions. In a multivariate logistic regression analysis, both sulcal SWI lesions (p < 0.001, OR 69, 95% CI 7.8-610) and contrast enhancement (p = 0.007, OR 16.5, 95% CI 2.3-121) were found to be significant predictors of the presence of IIAs. In the individuals with IE who underwent DSA and MRI, we found that neuroimaging characteristics, such as sulcal SWI lesion with or without contrast enhancement, are associated with the presence of IIA. © 2017 S. Karger AG, Basel.

  11. Evaluation of low-energy contrast-enhanced spectral mammography images by comparing them to full-field digital mammography using EUREF image quality criteria

    OpenAIRE

    Lalji, U. C.; Jeukens, C. R. L. P. N.; Houben, I.; Nelemans, P. J.; van Engen, R. E.; van Wylick, E.; Beets-Tan, R. G. H.; Wildberger, J. E.; Paulis, L. E.; Lobbes, M. B. I.

    2015-01-01

    Objective Contrast-enhanced spectral mammography (CESM) examination results in a low-energy (LE) and contrast-enhanced image. The LE appears similar to a full-field digital mammogram (FFDM). Our aim was to evaluate LE CESM image quality by comparing it to FFDM using criteria defined by the European Reference Organization for Quality Assured Breast Screening and Diagnostic Services (EUREF). Methods A total of 147 cases with both FFDM and LE images were independently scored by two experienced r...

  12. General Ultrasound Imaging

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    Full Text Available ... testing. image the breasts and guide biopsy of breast cancer ( see the Ultrasound-Guided Breast Biopsy page . diagnose ... Ultrasound is the preferred imaging modality for the diagnosis and monitoring of pregnant women and their unborn ...

  13. General Ultrasound Imaging

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    Full Text Available ... More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z General Ultrasound Ultrasound ... computer or television monitor. The image is created based on the amplitude (loudness), frequency (pitch) and time ...

  14. Meta-analysis: Serum creatinine changes following contrast enhanced CT imaging

    International Nuclear Information System (INIS)

    Kooiman, Judith; Pasha, Sharif M.; Zondag, Wendy; Sijpkens, Yvo W.J.; Molen, Aart J. van der; Huisman, Menno V.; Dekkers, Olaf M.

    2012-01-01

    Purpose: Contrast induced nephropathy (CIN) is defined as a decrease in renal function following administration of contrast media. The aim of this meta-analysis was to asses the overall risk of CIN, chronic loss of kidney function and the need for renal replacement therapy (RRT) after intravenous contrast enhanced CT-scan. Secondly, we aimed to identify subgroups at increased risk for CIN. Materials and methods: A literature search in Pubmed, Medline, Embase and Cochrane databases was performed. Data extraction was carried out independently by two reviewers. Meta-analysis and meta-regression were performed using an exact likelihood approach. Results: Forty studies evaluating the incidence of CIN after CT were included. The pooled incidence of CIN was 6.4% (95% CI 5.0–8.1). The risk of RRT after CIN was low, 0.06% (95% CI 0.01–0.4). The decline in renal function persisted in 1.1% of patients (95% CI 0.6–2.1%). Patients with chronic kidney disease (odds ratio 2.26, p < 0.001) or diabetes mellitus (odds ratio 3.10, p < 0.001) were at increased risk for the development of CIN. Conclusion: CIN occurred in 6% of patients after contrast enhanced CT. In 1% of all patients undergoing contrast enhanced CT the decline in renal function persisted

  15. Meta-analysis: Serum creatinine changes following contrast enhanced CT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kooiman, Judith, E-mail: j.kooiman@lumc.nl [Department of Thrombosis and Haemostasis, LUMC, Leiden (Netherlands); Pasha, Sharif M., E-mail: s.m.pasha@lumc.nl [Department of Thrombosis and Haemostasis, LUMC, Leiden (Netherlands); Zondag, Wendy, E-mail: w.zondag@lumc.nl [Department of Thrombosis and Haemostasis, LUMC, Leiden (Netherlands); Sijpkens, Yvo W.J., E-mail: ysijpens@bronovo.nl [Department of Nephrology, Bronovo Hospital, The Hague (Netherlands); Molen, Aart J. van der, E-mail: molen@lumc.nl [Department of Radiology, LUMC, Leiden (Netherlands); Huisman, Menno V., E-mail: m.v.huisman@lumc.nl [Department of Thrombosis and Haemostasis, LUMC, Leiden (Netherlands); Dekkers, Olaf M., E-mail: o.m.dekkers@lumc.nl [Department of Clinical Epidemiology and Department of Endocrinology, LUMC, Leiden (Netherlands)

    2012-10-15

    Purpose: Contrast induced nephropathy (CIN) is defined as a decrease in renal function following administration of contrast media. The aim of this meta-analysis was to asses the overall risk of CIN, chronic loss of kidney function and the need for renal replacement therapy (RRT) after intravenous contrast enhanced CT-scan. Secondly, we aimed to identify subgroups at increased risk for CIN. Materials and methods: A literature search in Pubmed, Medline, Embase and Cochrane databases was performed. Data extraction was carried out independently by two reviewers. Meta-analysis and meta-regression were performed using an exact likelihood approach. Results: Forty studies evaluating the incidence of CIN after CT were included. The pooled incidence of CIN was 6.4% (95% CI 5.0–8.1). The risk of RRT after CIN was low, 0.06% (95% CI 0.01–0.4). The decline in renal function persisted in 1.1% of patients (95% CI 0.6–2.1%). Patients with chronic kidney disease (odds ratio 2.26, p < 0.001) or diabetes mellitus (odds ratio 3.10, p < 0.001) were at increased risk for the development of CIN. Conclusion: CIN occurred in 6% of patients after contrast enhanced CT. In 1% of all patients undergoing contrast enhanced CT the decline in renal function persisted.

  16. Age-related contrast enhancement study of normal bone marrow in lumbar spinal MR imaging

    International Nuclear Information System (INIS)

    Kim, Young A; Ha, Doo Hoe

    1999-01-01

    The purpose of this study was to evaluate the degree of contrast enhancement of normal bone marrow in L-spine relating to aging and to determine the range of contrast enhancement in normal bone marrow. We analyzed a total of 120 patients (20 per decade) who had undergone lumbar spinal MRI and who ranged in age from the 2nd decade to more than the 7th. Bone marrow revealed no abnormal pathology. Sagittal T1-weighted spin echo sequences were obtained before and after gadolinium administration. For each sequence, a region of interest was drawn within the L1 vertebral body from the midsagittal slice. Signal intensity (SI) values of each sequence were ascertained and the percentage increase in SI was calculated. After contrast enhancement, lumbar MRI revealed no statistically significant in the percentage increase in SI of normal bone marrow in relation to aging. Most patients (99%) however showed an SI increase of between 10% and 49%. In only four, none of whom were aged over 40, was this increase above 50%. Lumbar MRI, revealed no statistically significant difference in percentage increase in SI in normal bone marrow relating to aging, but when the increase is above 50% in a patient aged over 40, bone marrow pathology should be further investigated

  17. Pathologic contrast enhancement of cerebral lesions: A comparative study using stereotactic CT, stereotactic MR imaging, and stereotactic biopsy

    International Nuclear Information System (INIS)

    Earnest, F. IV; Kelly, P.J.; Scheithauer, B.; Kall, B.; Cascino, T.L.; Ehman, R.L.; Forbes, G.

    1986-01-01

    The author compared the pattern and degree of Gd-DTPA dimeglumine contrast enhancement demonstrated on stereotactic MR images with that seen on stereotactic CT images obtained after conventional iodinated contrast agent enhancement and with histopathologic findings on sequential stereotactic brain biopsies. Stereotactic biopsies of the areas that enhanced on CT or MR imaging revealed tumor tissue with neovascularity. Tumor tissue with no or mild neovascularity did not enhance with contrast agent administration. Isolated tumor cells were frequently found beyond the margins of some primary brain neoplasms defined by contrast agent-enhanced MR imaging and CT. The histopathologic findings associated with pathologic contrast agent enhancement are presented

  18. Preoperative radiological characterization of hepatic angiomyolipoma using magnetic resonance imaging and contrast-enhanced ultrasonography: a case report

    Directory of Open Access Journals (Sweden)

    Schmid Roland M

    2011-09-01

    Full Text Available Abstract Introduction A hepatic angiomyolipoma is a rare benign tumor of the liver composed of a mixture of smooth muscle cells, blood vessels and a variable amount of adipose tissue. Differentiating them from malignant liver tumors can often be very difficult. Case presentation We report the case of a 43-year-old Caucasian man presenting with a large liver mass in the right lobe. The results of magnetic resonance imaging and contrast-enhanced ultrasonography were consistent with a well-demarcated adipose tissue- containing tumor, showing prolonged hyperperfusion in comparison with the surrounding liver tissue. Surgery was performed and the diagnosis of hepatic angiomyolipoma was made with histopathology. Conclusion Preoperative radiological characterization using magnetic resonance imaging and contrast-enhanced ultrasonography may improve diagnostic accuracy of hepatic angiomyolipoma. Identification of smooth muscle cells, blood vessels and adipose tissue with a positive immunohistochemical reaction for HMB-45 is the final evidence for an angiomyolipoma.

  19. Evaluation on changes of early renal function in patients with diabetic nephropathy with contrast-enhanced ultrasound and its clinical significance

    International Nuclear Information System (INIS)

    Guo Xinmin; Jin Hong; Pan Liwen; Chen Hui; Liu Wei; Quan Xianyue

    2013-01-01

    Objective: To quantitatively assess the parameter alteration of renal blood flow in patients with diabetic nephropathy (DN) with the contrast-enhanced ultrasound (CEUS), and to evaluate value of the technique in diagnosis of early renal function changes of DN patients. Methods: 40 diabetic patients were equally divided into two group according to Mogensen's staging criteria: normal albuminuria group (group Ⅰ) and early DN group (group Ⅱ); and 15 cases of healthy volunteers were used as control group (N group) (n=15). All subjects were performed renal CEUS perfusion imaging, and QontraXt image analysis software was applied to select the region of interest (ROI) in the renal cortex. Then the time intensity curve (TIC) and kidney blood perfusion parameters were collected. Results: The renal blood perfusion was clearly shown in real time CEUS; compared with N group, the time to peak (TTP), regional blood volume (RBV), and mean transit time (MTT) of the patients in group Ⅰ were increased, there were significant differences (P<0.05); but there were no significant differences of derived peak intensity (DPI) and regional blood flow (RBF) between two groups (P>0.05). Compared with group Ⅰ and N group, the RBV, TTP and MTT of the patients were increased, the DPI and RBF were reduced in group Ⅱ, there were significant differences (P<0.05). Conclusion: The CEUS technical analysis can be used in evaluating renal abnormality of the DN patients in early period by showing the changes of renal perfusion parameters. (authors)

  20. Myocardial blood flow estimates from dynamic contrast-enhanced magnetic resonance imaging: three quantitative methods

    Science.gov (United States)

    Borrazzo, Cristian; Galea, Nicola; Pacilio, Massimiliano; Altabella, Luisa; Preziosi, Enrico; Carnì, Marco; Ciolina, Federica; Vullo, Francesco; Francone, Marco; Catalano, Carlo; Carbone, Iacopo

    2018-02-01

    Dynamic contrast-enhanced cardiovascular magnetic resonance imaging can be used to quantitatively assess the myocardial blood flow (MBF), recovering the tissue impulse response function for the transit of a gadolinium bolus through the myocardium. Several deconvolution techniques are available, using various models for the impulse response. The method of choice may influence the results, producing differences that have not been deeply investigated yet. Three methods for quantifying myocardial perfusion have been compared: Fermi function modelling (FFM), the Tofts model (TM) and the gamma function model (GF), with the latter traditionally used in brain perfusion MRI. Thirty human subjects were studied at rest as well as under cold pressor test stress (submerging hands in ice-cold water), and a single bolus of gadolinium weighing 0.1  ±  0.05 mmol kg-1 was injected. Perfusion estimate differences between the methods were analysed by paired comparisons with Student’s t-test, linear regression analysis, and Bland-Altman plots, as well as also using the two-way ANOVA, considering the MBF values of all patients grouped according to two categories: calculation method and rest/stress conditions. Perfusion estimates obtained by various methods in both rest and stress conditions were not significantly different, and were in good agreement with the literature. The results obtained during the first-pass transit time (20 s) yielded p-values in the range 0.20-0.28 for Student’s t-test, linear regression analysis slopes between 0.98-1.03, and R values between 0.92-1.01. From the Bland-Altman plots, the paired comparisons yielded a bias (and a 95% CI)—expressed as ml/min/g—for FFM versus TM, -0.01 (-0.20, 0.17) or 0.02 (-0.49, 0.52) at rest or under stress respectively, for FFM versus GF, -0.05 (-0.29, 0.20) or  -0.07 (-0.55, 0.41) at rest or under stress, and for TM versus GF, -0.03 (-0.30, 0.24) or  -0.09 (-0.43, 0.26) at rest or under stress. With the

  1. Task-based strategy for optimized contrast enhanced breast imaging: analysis of six imaging techniques for mammography and tomosynthesis

    Science.gov (United States)

    Ikejimba, Lynda; Kiarashi, Nooshin; Lin, Yuan; Chen, Baiyu; Ghate, Sujata V.; Zerhouni, Moustafa; Samei, Ehsan; Lo, Joseph Y.

    2012-03-01

    Digital breast tomosynthesis (DBT) is a novel x-ray imaging technique that provides 3D structural information of the breast. In contrast to 2D mammography, DBT minimizes tissue overlap potentially improving cancer detection and reducing number of unnecessary recalls. The addition of a contrast agent to DBT and mammography for lesion enhancement has the benefit of providing functional information of a lesion, as lesion contrast uptake and washout patterns may help differentiate between benign and malignant tumors. This study used a task-based method to determine the optimal imaging approach by analyzing six imaging paradigms in terms of their ability to resolve iodine at a given dose: contrast enhanced mammography and tomosynthesis, temporal subtraction mammography and tomosynthesis, and dual energy subtraction mammography and tomosynthesis. Imaging performance was characterized using a detectability index d', derived from the system task transfer function (TTF), an imaging task, iodine contrast, and the noise power spectrum (NPS). The task modeled a 5 mm lesion containing iodine concentrations between 2.1 mg/cc and 8.6 mg/cc. TTF was obtained using an edge phantom, and the NPS was measured over several exposure levels, energies, and target-filter combinations. Using a structured CIRS phantom, d' was generated as a function of dose and iodine concentration. In general, higher dose gave higher d', but for the lowest iodine concentration and lowest dose, dual energy subtraction tomosynthesis and temporal subtraction tomosynthesis demonstrated the highest performance.

  2. Combined dynamic contrast-enhancement and serial 3D-subtraction analysis in magnetic resonance imaging of osteoid osteomas

    Energy Technology Data Exchange (ETDEWEB)

    Kalle, T. von; Winkler, P. [Klinikum Stuttgart Olgahospital, Department of Paediatric Radiology, Stuttgart (Germany); Langendoerfer, M.; Fernandez, F.F. [Klinikum Stuttgart Olgahospital, Department of Paediatric Orthopaedics, Stuttgart (Germany)

    2009-10-15

    The purpose of this study was to retrospectively correlate the results of dynamic contrast-enhanced magnetic resonance imaging (MRI) with histological and clinical diagnoses in patients with osteoid osteomas. Fifty-four patients with the MR diagnosis of osteoid osteoma were studied. MRI (1.5 Tesla) consisted of thin-section STIR sequences, dynamic 3D T1 gradient echo sequences during application of contrast material, and high-resolution postcontrast T1 spin echo sequences with fat saturation (maximum voxel size 0.6 x 0.6 x 3.0 mm). Evaluation was focused on serial image subtraction during the early phase after contrast injection and on time-intensity curves. The surrounding edema was helpful in finding the nidus in each lesion. In 49 of 54 patients (90.7%), the diagnosis of osteoid osteoma was certain or highly probable (sensitivity 1.0, positive predictive value 0.91). A total of 38 of 54 osteoid osteomas were histologically proven. Five MRI diagnoses were regarded as false positives. A similar proportion has been reported for computed tomography. Tailored high-resolution MR examinations with dynamic contrast enhancement can reliably diagnose osteoid osteomas and exactly localize the nidus without radiation exposure. We propose a stepwise approach with STIR sequences, dynamic contrast-enhanced scanning, and high-resolution postcontrast T1 spin echo sequences with fat saturation. (orig.)

  3. Combined dynamic contrast-enhancement and serial 3D-subtraction analysis in magnetic resonance imaging of osteoid osteomas

    International Nuclear Information System (INIS)

    Kalle, T. von; Winkler, P.; Langendoerfer, M.; Fernandez, F.F.

    2009-01-01

    The purpose of this study was to retrospectively correlate the results of dynamic contrast-enhanced magnetic resonance imaging (MRI) with histological and clinical diagnoses in patients with osteoid osteomas. Fifty-four patients with the MR diagnosis of osteoid osteoma were studied. MRI (1.5 Tesla) consisted of thin-section STIR sequences, dynamic 3D T1 gradient echo sequences during application of contrast material, and high-resolution postcontrast T1 spin echo sequences with fat saturation (maximum voxel size 0.6 x 0.6 x 3.0 mm). Evaluation was focused on serial image subtraction during the early phase after contrast injection and on time-intensity curves. The surrounding edema was helpful in finding the nidus in each lesion. In 49 of 54 patients (90.7%), the diagnosis of osteoid osteoma was certain or highly probable (sensitivity 1.0, positive predictive value 0.91). A total of 38 of 54 osteoid osteomas were histologically proven. Five MRI diagnoses were regarded as false positives. A similar proportion has been reported for computed tomography. Tailored high-resolution MR examinations with dynamic contrast enhancement can reliably diagnose osteoid osteomas and exactly localize the nidus without radiation exposure. We propose a stepwise approach with STIR sequences, dynamic contrast-enhanced scanning, and high-resolution postcontrast T1 spin echo sequences with fat saturation. (orig.)

  4. Marginal erosive discovertebral ''Romanus'' lesions in ankylosing spondylitis demonstrated by contrast enhanced Gd-DTPA magnetic resonance imaging

    International Nuclear Information System (INIS)

    Jevtic, V.; Kos-Golja, M.; Rozman, B.; McCall, I.

    2000-01-01

    Objective. To assess the value of Gd-DTPA magnetic resonance (MR) imaging in the demonstration of marginal destructive discovertebral Romanus lesions in ankylosing spondylitis.Design and patients. A prospective study of Gd-DTPA MR imaging was performed in 39 patients with a clinical diagnosis of ankylosing spondylitis and typical Romanus lesions seen on radiographs of the thoracolumbar spine. MR morphological appearances and signal intensity changes at the discovertebral junctions were analysed and compared with the radiographic findings.Results. Ninety-nine discovertebral junctions with Romanus lesions showed low signal intensity on T1-weighted and high signal on T2-weighted and T1-weighted postcontrast images at the vertebral corners consistent with oedematous hyperaemic inflammatory tissue. There were nine discovertebral junctions with similar MR findings but normal radiographs. Fifty-three discovertebral junctions showed syndesmophyte formation with increased signal intensity on both T1- and T2-weighted images with no contrast enhancement. Sixty-five discovertebral junctions showed a mixture of radiographic features and varied high and low signal changes at the vertebral rim on MR imaging with rims of enhancement in the vertebral body following contrast administration.Conclusion. Gd-DTPA MR imaging demonstrates a variable signal pattern and degree of contrast enhancement which may reflect the evolutionary stages of discovertebral enthesitis in ankylosing spondylitis. MR imaging may identify early erosive changes in radiographically normal vertebra. The role of MR imaging needs further investigation. (orig.)

  5. General Ultrasound Imaging

    Medline Plus

    Full Text Available ... 3-D) ultrasound that formats the sound wave data into 3-D images. A Doppler ultrasound study ... at these links. About Us | Contact Us | FAQ | Privacy | Terms of Use | Links | Site Map Copyright © 2018 ...

  6. General Ultrasound Imaging

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    Full Text Available ... 3-D) ultrasound that formats the sound wave data into 3-D images. A Doppler ultrasound study ... to do the scanning. The transducer is a small hand-held device that resembles a microphone, attached ...

  7. General Ultrasound Imaging

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    Full Text Available ... ultrasound. 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 ...

  8. General Ultrasound Imaging

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    Full Text Available ... ultrasound. top of page How does the procedure work? Ultrasound imaging is based on the same principles ... requested the exam. Usually, the referring physician or health care provider will share the results with you. ...

  9. General Ultrasound Imaging

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    Full Text Available ... need to be returned to the transducer for analysis. Ultrasound has difficulty penetrating bone and, therefore, can ... ultrasound procedure View full size with caption Pediatric Content Some imaging tests and treatments have special pediatric ...

  10. General Ultrasound Imaging

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    Full Text Available ... image. Ultrasound examinations do not use ionizing radiation (as used in x-rays ), thus there is no ... structure and movement of the body's internal organs, as well as blood flowing through blood vessels. Ultrasound ...

  11. General Ultrasound Imaging

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    Full Text Available ... Ultrasound is the preferred imaging modality for the diagnosis and monitoring of pregnant women and their unborn ... needle biopsies and fluid aspiration. Risks For standard diagnostic ultrasound , there are no known harmful effects on ...

  12. General Ultrasound Imaging

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    Full Text Available ... ultrasound. top of page How does the procedure work? Ultrasound imaging is based on the same principles ... more extensive exams may take up to an hour. When the examination is complete, you may be ...

  13. General Ultrasound Imaging

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    Full Text Available ... ultrasound. top of page How does the procedure work? Ultrasound imaging is based on the same principles ... have special pediatric considerations. The teddy bear denotes child-specific content. Related Articles and Media Angioplasty and ...

  14. General Ultrasound Imaging

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    Full Text Available ... ultrasound. top of page How does the procedure work? Ultrasound imaging is based on the same principles ... about this beforehand and be made aware of food and drink restrictions that may be needed prior ...

  15. General Ultrasound Imaging

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    Full Text Available ... Ultrasound is safe, noninvasive, and does not use ionizing radiation. This procedure requires little to no special preparation. ... create an image. Ultrasound examinations do not use ionizing radiation (as used in x-rays ), thus there is ...

  16. General Ultrasound Imaging

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    Full Text Available ... ultrasound. top of page How does the procedure work? Ultrasound imaging is based on the same principles ... the transducer is pressed against the skin, it directs small pulses of inaudible, high-frequency sound waves ...

  17. Gaussian process inference for estimating pharmacokinetic parameters of dynamic contrast-enhanced MR images.

    Science.gov (United States)

    Wang, Shijun; Liu, Peter; Turkbey, Baris; Choyke, Peter; Pinto, Peter; Summers, Ronald M

    2012-01-01

    In this paper, we propose a new pharmacokinetic model for parameter estimation of dynamic contrast-enhanced (DCE) MRI by using Gaussian process inference. Our model is based on the Tofts dual-compartment model for the description of tracer kinetics and the observed time series from DCE-MRI is treated as a Gaussian stochastic process. The parameter estimation is done through a maximum likelihood approach and we propose a variant of the coordinate descent method to solve this likelihood maximization problem. The new model was shown to outperform a baseline method on simulated data. Parametric maps generated on prostate DCE data with the new model also provided better enhancement of tumors, lower intensity on false positives, and better boundary delineation when compared with the baseline method. New statistical parameter maps from the process model were also found to be informative, particularly when paired with the PK parameter maps.

  18. Delayed contrast enhancement imaging of a murine model for ischemia reperfusion with carbon nanotube micro-CT.

    Directory of Open Access Journals (Sweden)

    Laurel M Burk

    Full Text Available We aim to demonstrate the application of free-breathing prospectively gated carbon nanotube (CNT micro-CT by evaluating a myocardial infarction model with a delayed contrast enhancement technique. Evaluation of murine cardiac models using micro-CT imaging has historically been limited by extreme imaging requirements. Newly-developed CNT-based x-ray sources offer precise temporal resolution, allowing elimination of physiological motion through prospective gating. Using free-breathing, cardiac-gated CNT micro-CT, a myocardial infarction model can be studied non-invasively and with high resolution. Myocardial infarction was induced in eight male C57BL/6 mice aged 8-12 weeks. The ischemia reperfusion model was achieved by surgically occluding the LAD artery for 30 minutes followed by 24 hours of reperfusion. Tail vein catheters were placed for contrast administration. Iohexol 300 mgI/mL was administered followed by images obtained in diastole. Iodinated lipid blood pool contrast agent was then administered, followed with images at systole and diastole. Respiratory and cardiac signals were monitored externally and used to gate the scans of free-breathing subjects. Seven control animals were scanned using the same imaging protocol. After imaging, the heart was harvested, cut into 1mm slices and stained with TTC. Post-processing analysis was performed using ITK-Snap and MATLAB. All animals demonstrated obvious delayed contrast enhancement in the left ventricular wall following the Iohexol injection. The blood pool contrast agent revealed significant changes in cardiac function quantified by 3-D volume ejection fractions. All subjects demonstrated areas of myocardial infarct in the LAD distribution on both TTC staining and micro-CT imaging. The CNT micro-CT system aids straightforward, free-breathing, prospectively-gated 3-D murine cardiac imaging. Delayed contrast enhancement allows identification of infarcted myocardium after a myocardial ischemic

  19. Enhancement characteristics of benign and malignant focal peripheral nodules in the peripheral zone of the prostate gland studied using contrast-enhanced transrectal ultrasound

    International Nuclear Information System (INIS)

    Tang, J.; Yang, J.-C.; Luo, Y.; Li, J.; Li, Y.; Shi, H.

    2008-01-01

    Aim: To assess the value of contrast-enhanced grey-scale transrectal ultrasound (CETRUS) in predicting the nature of peripheral zone hypoechoic lesions of the prostate. Materials and Methods: Ninety-one patients with peripheral zone hypoechoic lesions on ultrasound were evaluated with CETRUS followed by lesion-specific and sextant transrectal ultrasound-guided biopsies. The enhancement patterns of the lesions were observed and graded subjectively using adjacent peripheral zone tissue as the reference. Time to enhancement (AT), time to peak intensity (TTP) and peak intensity (PI) were quantified within each nodule. Ultrasound findings were correlated with biopsy findings. Results: Transrectal ultrasound-guided biopsy of the hypoechoic lesions revealed prostate cancer in 44 patients and benign prostatic diseases in 47. The intensity of enhancement within the lesions were graded as no enhancement, increased, equal, or decreased compared with adjacent peripheral zone tissue in two, 30, five and seven in the prostate cancer group and 14, 15, four and 14 in the benign group, respectively. The difference was statistically significant (p < 0.05). The peak enhancement intensity was found to be the most optimal discriminatory parameter (area under curve AUC 0.70; 95% CI: 0.58, 0.82). Conclusion: Malignant hypoechoic nodules in the peripheral zone of the prostate are more likely to enhance early and more intensely on CETRUS. A non-enhanced hypoechoic peripheral zone lesion was more likely to be benign

  20. SU-E-J-16: Automatic Image Contrast Enhancement Based On Automatic Parameter Optimization for Radiation Therapy Setup Verification

    Energy Technology Data Exchange (ETDEWEB)

    Qiu, J [Taishan Medical University, Taian, Shandong (China); Washington University in St Louis, St Louis, MO (United States); Li, H. Harlod; Zhang, T; Yang, D [Washington University in St Louis, St Louis, MO (United States); Ma, F [Taishan Medical University, Taian, Shandong (China)

    2015-06-15

    Purpose: In RT patient setup 2D images, tissues often cannot be seen well due to the lack of image contrast. Contrast enhancement features provided by image reviewing software, e.g. Mosaiq and ARIA, require manual selection of the image processing filters and parameters thus inefficient and cannot be automated. In this work, we developed a novel method to automatically enhance the 2D RT image contrast to allow automatic verification of patient daily setups as a prerequisite step of automatic patient safety assurance. Methods: The new method is based on contrast limited adaptive histogram equalization (CLAHE) and high-pass filtering algorithms. The most important innovation is to automatically select the optimal parameters by optimizing the image contrast. The image processing procedure includes the following steps: 1) background and noise removal, 2) hi-pass filtering by subtracting the Gaussian smoothed Result, and 3) histogram equalization using CLAHE algorithm. Three parameters were determined through an iterative optimization which was based on the interior-point constrained optimization algorithm: the Gaussian smoothing weighting factor, the CLAHE algorithm block size and clip limiting parameters. The goal of the optimization is to maximize the entropy of the processed Result. Results: A total 42 RT images were processed. The results were visually evaluated by RT physicians and physicists. About 48% of the images processed by the new method were ranked as excellent. In comparison, only 29% and 18% of the images processed by the basic CLAHE algorithm and by the basic window level adjustment process, were ranked as excellent. Conclusion: This new image contrast enhancement method is robust and automatic, and is able to significantly outperform the basic CLAHE algorithm and the manual window-level adjustment process that are currently used in clinical 2D image review software tools.

  1. SU-E-J-16: Automatic Image Contrast Enhancement Based On Automatic Parameter Optimization for Radiation Therapy Setup Verification

    International Nuclear Information System (INIS)

    Qiu, J; Li, H. Harlod; Zhang, T; Yang, D; Ma, F

    2015-01-01

    Purpose: In RT patient setup 2D images, tissues often cannot be seen well due to the lack of image contrast. Contrast enhancement features provided by image reviewing software, e.g. Mosaiq and ARIA, require manual selection of the image processing filters and parameters thus inefficient and cannot be automated. In this work, we developed a novel method to automatically enhance the 2D RT image contrast to allow automatic verification of patient daily setups as a prerequisite step of automatic patient safety assurance. Methods: The new method is based on contrast limited adaptive histogram equalization (CLAHE) and high-pass filtering algorithms. The most important innovation is to automatically select the optimal parameters by optimizing the image contrast. The image processing procedure includes the following steps: 1) background and noise removal, 2) hi-pass filtering by subtracting the Gaussian smoothed Result, and 3) histogram equalization using CLAHE algorithm. Three parameters were determined through an iterative optimization which was based on the interior-point constrained optimization algorithm: the Gaussian smoothing weighting factor, the CLAHE algorithm block size and clip limiting parameters. The goal of the optimization is to maximize the entropy of the processed Result. Results: A total 42 RT images were processed. The results were visually evaluated by RT physicians and physicists. About 48% of the images processed by the new method were ranked as excellent. In comparison, only 29% and 18% of the images processed by the basic CLAHE algorithm and by the basic window level adjustment process, were ranked as excellent. Conclusion: This new image contrast enhancement method is robust and automatic, and is able to significantly outperform the basic CLAHE algorithm and the manual window-level adjustment process that are currently used in clinical 2D image review software tools

  2. Contrast-enhanced spectral mammography in neoadjuvant chemotherapy monitoring: a comparison with breast magnetic resonance imaging.

    Science.gov (United States)

    Iotti, Valentina; Ravaioli, Sara; Vacondio, Rita; Coriani, Chiara; Caffarri, Sabrina; Sghedoni, Roberto; Nitrosi, Andrea; Ragazzi, Moira; Gasparini, Elisa; Masini, Cristina; Bisagni, Giancarlo; Falco, Giuseppe; Ferrari, Guglielmo; Braglia, Luca; Del Prato, Alberto; Malavolti, Ivana; Ginocchi, Vladimiro; Pattacini, Pierpaolo

    2017-09-11

    Neoadjuvant-chemotherapy (NAC) is considered the standard treatment for locally advanced breast carcinomas. Accurate assessment of disease response is fundamental to increase the chances of successful breast-conserving surgery and to avoid local recurrence. The purpose of this study was to compare contrast-enhanced spectral mammography (CESM) and contrast-enhanced-MRI (MRI) in the evaluation of tumor response to NAC. This prospective study was approved by the institutional review board and written informed consent was obtained. Fifty-four consenting women with breast cancer and indication of NAC were consecutively enrolled between October 2012 and December 2014. Patients underwent both CESM and MRI before, during and after NAC. MRI was performed first, followed by CESM within 3 days. Response to therapy was evaluated for each patient, comparing the size of the residual lesion measured on CESM and MRI performed after NAC to the pathological response on surgical specimens (gold standard), independently of and blinded to the results of the other test. The agreement between measurements was evaluated using Lin's coefficient. The agreement between measurements using CESM and MRI was tested at each step of the study, before, during and after NAC. And last of all, the variation in the largest dimension of the tumor on CESM and MRI was assessed according to the parameters set in RECIST 1.1 criteria, focusing on pathological complete response (pCR). A total of 46 patients (85%) completed the study. CESM predicted pCR better than MRI (Lin's coefficient 0.81 and 0.59, respectively). Both methods tend to underestimate the real extent of residual tumor (mean 4.1mm in CESM, 7.5mm in MRI). The agreement between measurements using CESM and MRI was 0.96, 0.94 and 0.76 before, during and after NAC respectively. The distinction between responders and non-responders with CESM and MRI was identical for 45/46 patients. In the assessment of CR, sensitivity and specificity were 100% and

  3. Added value of contrast-enhanced CISS imaging in relation to conventional MR images for the evaluation of intracavernous cranial nerve lesions

    Energy Technology Data Exchange (ETDEWEB)

    Yagi, Akiko; Takahashi, Ayako; Morita, Hideo; Amanuma, Makoto; Endo, Keigo [Gunma University School of Medicine, Department of Diagnostic Radiology and Nuclear Medicine, Gunma (Japan); Sato, Noriko [National Center Hospital of Neurology and Psychiatry, Department of Radiology, Kodaira, Tokyo (Japan); Takeuchi, K. [Takasaki University of Health and Welfare, Department of Health and Welfare, Gunma (Japan)

    2010-12-15

    The normal cranial nerves (CNs) of the cavernous sinus can be clearly demonstrated using contrast-enhanced constructive interference in steady-state (CISS) magnetic resonance imaging (MRI). This study used the method to evaluate pathological CNs III, IV, V{sub 1}, V{sub 2}, and VI in cavernous sinuses affected by inflammatory and neoplastic diseases. MR images from 17 patients with diseases involving the cavernous sinuses and/or causing neuropathy in CNs III-VI were retrospectively evaluated. The patients were divided into inflammatory (n = 11) and neoplastic (n = 6) groups. We defined CNs as abnormal when they exhibited enlargement or enhancement. CNs were evaluated using both contrast-enhanced CISS and T1-weighted MRI. In the inflammatory group, abnormal CNs were identified by contrast-enhanced CISS MRI in 13 of 25 symptomatic CNs (52%) in eight patients, but in only two CNs (8%) in two patients by contrast-enhanced T1-weighted MRI. In the neoplastic group, both sequences of contrast-enhanced CISS and T1-weighted MRI detected abnormalities in the same three of eight symptomatic CNs (37.5%), i.e., the three CNs were all in the same patient with adenoid cystic carcinoma. Contrast-enhanced CISS MRI is useful for detecting CN abnormalities in inflammatory pathological conditions of the cavernous sinuses. (orig.)

  4. General Ultrasound Imaging

    Medline Plus

    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 General Ultrasound Imaging? Ultrasound waves are ...

  5. Content-based image retrieval using spatial layout information in brain tumor T1-weighted contrast-enhanced MR images.

    Science.gov (United States)

    Huang, Meiyan; Yang, Wei; Wu, Yao; Jiang, Jun; Gao, Yang; Chen, Yang; Feng, Qianjin; Chen, Wufan; Lu, Zhentai

    2014-01-01

    This study aims to develop content-based image retrieval (CBIR) system for the retrieval of T1-weighted contrast-enhanced MR (CE-MR) images of brain tumors. When a tumor region is fed to the CBIR system as a query, the system attempts to retrieve tumors of the same pathological category. The bag-of-visual-words (BoVW) model with partition learning is incorporated into the system to extract informative features for representing the image contents. Furthermore, a distance metric learning algorithm called the Rank Error-based Metric Learning (REML) is proposed to reduce the semantic gap between low-level visual features and high-level semantic concepts. The effectiveness of the proposed method is evaluated on a brain T1-weighted CE-MR dataset with three types of brain tumors (i.e., meningioma, glioma, and pituitary tumor). Using the BoVW model with partition learning, the mean average precision (mAP) of retrieval increases beyond 4.6% with the learned distance metrics compared with the spatial pyramid BoVW method. The distance metric learned by REML significantly outperforms three other existing distance metric learning methods in terms of mAP. The mAP of the CBIR system is as high as 91.8% using the proposed method, and the precision can reach 93.1% when the top 10 images are returned by the system. These preliminary results demonstrate that the proposed method is effective and feasible for the retrieval of brain tumors in T1-weighted CE-MR Images.

  6. Content-based image retrieval using spatial layout information in brain tumor T1-weighted contrast-enhanced MR images.

    Directory of Open Access Journals (Sweden)

    Meiyan Huang

    Full Text Available This study aims to develop content-based image retrieval (CBIR system for the retrieval of T1-weighted contrast-enhanced MR (CE-MR images of brain tumors. When a tumor region is fed to the CBIR system as a query, the system attempts to retrieve tumors of the same pathological category. The bag-of-visual-words (BoVW model with partition learning is incorporated into the system to extract informative features for representing the image contents. Furthermore, a distance metric learning algorithm called the Rank Error-based Metric Learning (REML is proposed to reduce the semantic gap between low-level visual features and high-level semantic concepts. The effectiveness of the proposed method is evaluated on a brain T1-weighted CE-MR dataset with three types of brain tumors (i.e., meningioma, glioma, and pituitary tumor. Using the BoVW model with partition learning, the mean average precision (mAP of retrieval increases beyond 4.6% with the learned distance metrics compared with the spatial pyramid BoVW method. The distance metric learned by REML significantly outperforms three other existing distance metric learning methods in terms of mAP. The mAP of the CBIR system is as high as 91.8% using the proposed method, and the precision can reach 93.1% when the top 10 images are returned by the system. These preliminary results demonstrate that the proposed method is effective and feasible for the retrieval of brain tumors in T1-weighted CE-MR Images.

  7. Discrimination between benign and malignant breast lesions using volumetric quantitative dynamic contrast-enhanced MR imaging

    International Nuclear Information System (INIS)

    Cheng, Ziliang; Wu, Zhuo; Shen, Jun; Shi, Guangzi; Yi, Zhilong; Xie, Mingwei; Zeng, Weike; Song, Chao; Zheng, Chushan

    2018-01-01

    To determine the diagnostic performance of volumetric quantitative dynamic contrast-enhanced MRI (qDCE-MRI) in differentiation between malignant and benign breast lesions. DCE-MRI was performed in 124 patients with 136 breast lesions. Quantitative pharmacokinetic parameters K trans , K ep , V e , V p and semi-quantitative parameters TTP, MaxCon, MaxSlope, AUC were obtained by using a two-compartment extended Tofts model and three-dimensional volume of interest. Morphologic features (lesion size, margin, internal enhancement pattern) and time-signal intensity curve (TIC) type were also assessed. Logistic regression analysis was used to determine predictors of malignancy, followed by receiver operating characteristics (ROC) analysis to evaluate the diagnostic performance. qDCE parameters (K trans , K ep , V p , TTP, MaxCon, MaxSlope and AUC), morphological parameters and TIC type were significantly different between malignant and benign lesions (P≤0.001). Multivariate logistic regression analyses showed that K trans , K ep , MaxSlope, size, margin and TIC type were independent predictors of malignancy. The diagnostic accuracy of logistic models based on qDCE parameters alone, morphological features plus TIC type, and all parameters combined was 94.9%, 89.0%, and 95.6% respectively. qDCE-MRI can be used to improve diagnostic differentiation between benign and malignant breast lesions in relation to morphology and kinetic analysis. (orig.)

  8. Discrimination between benign and malignant breast lesions using volumetric quantitative dynamic contrast-enhanced MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Ziliang; Wu, Zhuo; Shen, Jun [Sun Yat-Sen University, Department of Radiology, Sun Yat-Sen Memorial Hospital, Guangzhou, Guangdong (China); Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Malignant Tumour Epigenetics and Gene Regulation, Medical Research Centre, Sun Yat-Sen Memorial Hospital, Guangzhou (China); Shi, Guangzi; Yi, Zhilong; Xie, Mingwei; Zeng, Weike; Song, Chao; Zheng, Chushan [Sun Yat-Sen University, Department of Radiology, Sun Yat-Sen Memorial Hospital, Guangzhou, Guangdong (China)

    2018-03-15

    To determine the diagnostic performance of volumetric quantitative dynamic contrast-enhanced MRI (qDCE-MRI) in differentiation between malignant and benign breast lesions. DCE-MRI was performed in 124 patients with 136 breast lesions. Quantitative pharmacokinetic parameters K{sup trans}, K{sub ep}, V{sub e}, V{sub p} and semi-quantitative parameters TTP, MaxCon, MaxSlope, AUC were obtained by using a two-compartment extended Tofts model and three-dimensional volume of interest. Morphologic features (lesion size, margin, internal enhancement pattern) and time-signal intensity curve (TIC) type were also assessed. Logistic regression analysis was used to determine predictors of malignancy, followed by receiver operating characteristics (ROC) analysis to evaluate the diagnostic performance. qDCE parameters (K{sup trans}, K{sub ep}, V{sub p}, TTP, MaxCon, MaxSlope and AUC), morphological parameters and TIC type were significantly different between malignant and benign lesions (P≤0.001). Multivariate logistic regression analyses showed that K{sup trans}, K{sub ep}, MaxSlope, size, margin and TIC type were independent predictors of malignancy. The diagnostic accuracy of logistic models based on qDCE parameters alone, morphological features plus TIC type, and all parameters combined was 94.9%, 89.0%, and 95.6% respectively. qDCE-MRI can be used to improve diagnostic differentiation between benign and malignant breast lesions in relation to morphology and kinetic analysis. (orig.)

  9. Dynamic contrast-enhanced magnetic resonance imaging and pharmacokinetic models in prostate cancer

    International Nuclear Information System (INIS)

    Franiel, Tobias; Hamm, Bernd; Hricak, Hedvig

    2011-01-01

    Dynamic contrast-enhanced MRI enables noninvasive analysis of prostate vascularization as well as tumour angiogenesis and capillary permeability characteristics in prostate cancers. Pharmacokinetic models summarizing the complex information provided by signal intensity-time curves for a few quantitative pharmacokinetic parameters are increasingly being used in the routine clinical setting. This review consists of two parts. The first part discusses the advantages and disadvantages of the MR pulse sequences that can be used for performing DCE-MRI and also of the most widely used pharmacokinetic parameters and models and the parameters they describe. The second part outlines the range of current and potential future clinical applications of DCE-MRI and pharmacokinetic parametric maps in patients with prostate cancer, with reference to the current scientific literature on the topic. The potential clinical applications of DCE-MRI for prostate cancer include detection, localization, and staging, differentiation of recurrent cancer and estimation of the patient's prognosis, as well as monitoring of treatment response. (orig.)

  10. Usefulness and biological background of dynamic contrast-enhanced MR images in patients with primary breast cancer

    International Nuclear Information System (INIS)

    Yamamoto, Yutaka; Kurebayashi, Junichi; Sonoo, Hiroshi

    2002-01-01

    Dynamic contrast-enhanced MR images were obtained between September 1998 and May 2000 from 44 primary breast cancer patients who were scheduled to undergo breast-conserving surgery. The MR images and clinico-pathological findings were analyzed to investigate the risk factors for histologically positive margins and histologically positive lymph node metastases. We elucidated the relationship between MR images and the biological background of breast cancer. The following interesting findings were made from these analyses. An irregular shape and unclear border of the tumor mass and the coexistence of daughter nodule(s) were significant risk factors for positive-surgical margins; an irregularly shaped tumor mass and spiculated tumor mass were significant risk factors for positive lymph node metastases; breast tumors with a strand-like appearance had a significantly lower histological grade; breast tumors with high contrast enhancement ratios had a significantly higher nuclear grade and progesterone receptor negativity; and breast tumors showing a ring-like enhancement expressed a low level of VEGF. These findings suggest that preoperative MR images of primary breast cancer provide not only useful information on the extent of breast tumors and the possibility of lymph node metastasis but also on the malignant potency and hormone responsiveness of breast tumors. (author)

  11. Medical ultrasound imaging

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt

    2007-01-01

    The paper gives an introduction to current medical ultrasound imaging systems. The basics of anatomic and blood flow imaging are described. The properties of medical ultrasound and its focusing are described, and the various methods for two- and three-dimensional imaging of the human anatomy...

  12. General Ultrasound Imaging

    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. ...

  13. Tracer kinetic model selection for dynamic contrast-enhanced magnetic resonance imaging of locally advanced cervical cancer

    DEFF Research Database (Denmark)

    Kallehauge, Jesper Folsted; Tanderup, Kari; Duan, Chong

    2014-01-01

    , the TM was optimal in 17.0%, the ETM was optimal in 2.2%, the C-TU in 23.4% and the 2CXM was optimal in 57.3%. Throughout the tumour, a high correlation was found between Ktrans(TM) and Fp(2CXM), ρ = 0.91. Conclusion. The 2CXM was most often optimal in describing the contrast agent enhancement of pre......Background. Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) offers a unique capability to probe tumour microvasculature. Different analysis of the acquired data will possibly lead to different conclusions. Therefore, the objective of this study was to investigate under which...

  14. Evaluation of heart perfusion in patients with acute myocardial infarction using dynamic contrast-enhanced magnetic resonance imaging

    DEFF Research Database (Denmark)

    Nielsen, Gitte; Fritz-Hansen, Thomas; Dirks, Christina G

    2004-01-01

    with acute transmural myocardial infarction were studied using a Turbo-fast low angle shot (FLASH) MRI sequence to monitor the first pass of an extravascular contrast agent (CA), gadolinium diethylene triamine pentaacetic acid (Gd-DTPA). Quantitation of perfusion, expressed as Ki (mL/100 g/minute), in five......PURPOSE: To investigate the diagnostic ability of quantitative magnetic resonance imaging (MRI) heart perfusion in acute heart patients, a fast, multislice dynamic contrast-enhanced MRI sequence was applied to patients with acute myocardial infarction. MATERIALS AND METHODS: Seven patients...

  15. Newly Diagnosed Breast Cancer: Comparison of Contrast-enhanced Spectral Mammography and Breast MR Imaging in the Evaluation of Extent of Disease.

    Science.gov (United States)

    Lee-Felker, Stephanie A; Tekchandani, Leena; Thomas, Mariam; Gupta, Esha; Andrews-Tang, Denise; Roth, Antoinette; Sayre, James; Rahbar, Guita

    2017-11-01

    Purpose To compare the diagnostic performances of contrast material-enhanced spectral mammography and breast magnetic resonance (MR) imaging in the detection of index and secondary cancers in women with newly diagnosed breast cancer by using histologic or imaging follow-up as the standard of reference. Materials and Methods This institutional review board-approved, HIPAA-compliant, retrospective study included 52 women who underwent breast MR imaging and contrast-enhanced spectral mammography for newly diagnosed unilateral breast cancer between March 2014 and October 2015. Of those 52 patients, 46 were referred for contrast-enhanced spectral mammography and targeted ultrasonography because they had additional suspicious lesions at MR imaging. In six of the 52 patients, breast cancer had been diagnosed at an outside institution. These patients were referred for contrast-enhanced spectral mammography and targeted US as part of diagnostic imaging. Images from contrast-enhanced spectral mammography were analyzed by two fellowship-trained breast imagers with 2.5 years of experience with contrast-enhanced spectral mammography. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value were calculated for both imaging modalities and compared by using the Bennett statistic. Results Fifty-two women with 120 breast lesions were included for analysis (mean age, 50 years; range, 29-73 years). Contrast-enhanced spectral mammography had similar sensitivity to MR imaging (94% [66 of 70 lesions] vs 99% [69 of 70 lesions]), a significantly higher PPV than MR imaging (93% [66 of 71 lesions] vs 60% [69 of 115 lesions]), and fewer false-positive findings than MR imaging (five vs 45) (P contrast-enhanced spectral mammography depicted 11 of the 11 secondary cancers (100%) and MR imaging depicted 10 (91%). Conclusion Contrast-enhanced spectral mammography is potentially as sensitive as MR imaging in the evaluation of extent of disease in newly diagnosed

  16. Assessment of irradiated brain metastases using dynamic contrast-enhanced magnetic resonance imaging

    International Nuclear Information System (INIS)

    Almeida-Freitas, Daniela B.; Pinho, Marco C.; Otaduy, Maria C.G.; Costa Leite, Claudia da; Braga, Henrique F.; Meira-Freitas, Daniel

    2014-01-01

    The purpose of this study was to evaluate the effect of stereotactic radiosurgery (SRS) on cerebral metastases using the transfer constant (K trans ) assessed by dynamic contrast-enhanced (DCE) MRI. Furthermore, we aimed to evaluate the ability of K trans measurements to predict midterm tumor outcomes after SRS. The study received institutional review board approval, and informed consent was obtained from all subjects. Twenty-six adult patients with a total of 34 cerebral metastases underwent T1-weighted DCE MRI in a 1.5-T magnet at baseline (prior to SRS) and 4-8 weeks after treatment. Quantitative analysis of DCE MRI was performed by generating K trans parametric maps, and region-of-interest-based measurements were acquired for each metastasis. Conventional MRI was performed at least 16 weeks after SRS to assess midterm tumor outcome using volume variation. The mean (±SD) K trans value was 0.13 ± 0.11 min -1 at baseline and 0.08 ± 0.07 min -1 after 4-8 weeks post-treatment (p trans after SRS was predictive of tumor progression (hazard ratio = 1.50; 95 % CI = 1.16-1.70, p trans showed a sensitivity of 78 % and a specificity of 85 % for the prediction of progression at midterm follow-up. SRS was associated with a reduction of K trans values of the cerebral metastases in the early post-treatment period. Furthermore, K trans variation as assessed using DCE MRI may be helpful to predict midterm outcomes after SRS. (orig.)

  17. Development and image quality assessment of a contrast-enhancement algorithm for display of digital chest radiographs

    International Nuclear Information System (INIS)

    Rehm, K.

    1992-01-01

    This dissertation presents a contrast-enhancement algorithm Artifact-Suppressed Adaptive Histogram Equalization (ASAHE). This algorithm was developed as part of a larger effort to replace the film radiographs currently used in radiology departments with digital images. Among the expected benefits of digital radiology are improved image management and greater diagnostic accuracy. Film radiographs record X-ray transmission data at high spatial resolution, and a wide dynamic range of signal. Current digital radiography systems record an image at reduced spatial resolution and with coarse sampling of the available dynamic range. These reductions have a negative impact on diagnostic accuracy. The contrast-enhancement algorithm presented in this dissertation is designed to boost diagnostic accuracy of radiologists using digital images. The ASAHE algorithm is an extension of an earlier technique called Adaptive Histogram Equalization (AHE). The AHE algorithm is unsuitable for chest radiographs because it over-enhances noise, and introduces boundary artifacts. The modifications incorporated in ASAHE suppress the artifacts and allow processing of chest radiographs. This dissertation describes the psychophysical methods used to evaluate the effects of processing algorithms on human observer performance. An experiment conducted with anthropomorphic phantoms and simulated nodules showed the ASAHE algorithm to be superior for human detection of nodules when compared to a computed radiography system's algorithm that is in current use. An experiment conducted using clinical images demonstrating pneumothoraces (partial lung collapse) indicated no difference in human observer accuracy when ASAHE images were compared to computed radiography images, but greater ease of diagnosis when ASAHE images were used. These results provide evidence to suggest that Artifact-Suppressed Adaptive Histogram Equalization can be effective in increasing diagnostic accuracy and efficiency

  18. 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.

  19. Contrast-Enhanced Ultrasound with VEGFR2-Targeted Microbubbles for Monitoring Regorafenib Therapy Effects in Experimental Colorectal Adenocarcinomas in Rats with DCE-MRI and Immunohistochemical Validation.

    Directory of Open Access Journals (Sweden)

    Ralf Stefan Eschbach

    Full Text Available To investigate contrast-enhanced ultrasound (CEUS with VEGFR2-targeted microbubbles for monitoring therapy effects of regorafenib on experimental colon carcinomas in rats with correlation to dynamic contrast-enhanced MRI (DCE-MRI and immunohistochemistry.Human colorectal adenocarcinoma xenografts (HT-29 were implanted subcutaneously in n = 21 (n = 11 therapy group; n = 10 control group female athymic nude rats (Hsd: RH-Foxn1rnu. Animals were imaged at baseline and after a one-week daily treatment with regorafenib or a placebo (10 mg/kg bodyweight, using CEUS with VEGFR2-targeted microbubbles and DCE-MRI. In CEUS tumor perfusion was assessed during an early vascular phase (wash-in area under the curve = WiAUC and VEGFR2-specific binding during a late molecular phase (signal intensity after 8 (SI8min and 10 minutes (SI10min, using a conventional 15L8 linear transducer (transmit frequency 7 MHz, dynamic range 80 dB, depth 25 mm. In DCE-MRI functional parameters plasma flow (PF and plasma volume (PV were quantified. For validation purposes, CEUS parameters were correlated with DCE-MRI parameters and immunohistochemical VEGFR2, CD31, Ki-67 and TUNEL stainings.CEUS perfusion parameter WiAUC decreased significantly (116,989 ± 77,048 a.u. to 30,076 ± 27,095a.u.; p = 0.005 under therapy with no significant changes (133,932 ± 65,960 a.u. to 84,316 ± 74,144 a.u.; p = 0.093 in the control group. In the therapy group, the amount of bound microbubbles in the late phase was significantly lower in the therapy than in the control group on day 7 (SI8min: 283 ± 191 vs. 802 ± 460 a.u.; p = 0.006; SI10min: 226 ± 149 vs. 645 ± 461 a.u.; p = 0.009. PF and PV decreased significantly (PF: 147 ± 58 mL/100 mL/min to 71 ± 15 mL/100 mL/min; p = 0.003; PV: 13 ± 3% to 9 ± 4%; p = 0.040 in the therapy group. Immunohistochemistry revealed significantly fewer VEGFR2 (7.2 ± 1.8 vs. 17.8 ± 4.6; p < 0.001, CD31 (8.1 ± 3.0 vs. 20.8 ± 5.7; p < 0.001 and Ki-67 (318.7

  20. Half-unit weighted bilinear algorithm for image contrast enhancement in capsule endoscopy

    Science.gov (United States)

    Rukundo, Olivier

    2018-04-01

    This paper proposes a novel enhancement method based exclusively on the bilinear interpolation algorithm for capsule endoscopy images. The proposed method does not convert the original RBG image components to HSV or any other color space or model; instead, it processes directly RGB components. In each component, a group of four adjacent pixels and half-unit weight in the bilinear weighting function are used to calculate the average pixel value, identical for each pixel in that particular group. After calculations, groups of identical pixels are overlapped successively in horizontal and vertical directions to achieve a preliminary-enhanced image. The final-enhanced image is achieved by halving the sum of the original and preliminary-enhanced image pixels. Quantitative and qualitative experiments were conducted focusing on pairwise comparisons between original and enhanced images. Final-enhanced images have generally the best diagnostic quality and gave more details about the visibility of vessels and structures in capsule endoscopy images.

  1. Average arterial input function for quantitative dynamic contrast enhanced magnetic resonance imaging of neck nodal metastases

    International Nuclear Information System (INIS)

    Shukla-Dave, Amita; Lee, Nancy; Stambuk, Hilda; Wang, Ya; Huang, Wei; Thaler, Howard T; Patel, Snehal G; Shah, Jatin P; Koutcher, Jason A

    2009-01-01

    The present study determines the feasibility of generating an average arterial input function (Avg-AIF) from a limited population of patients with neck nodal metastases to be used for pharmacokinetic modeling of dynamic contrast-enhanced MRI (DCE-MRI) data in clinical trials of larger populations. Twenty patients (mean age 50 years [range 27–77 years]) with neck nodal metastases underwent pretreatment DCE-MRI studies with a temporal resolution of 3.75 to 7.5 sec on a 1.5T clinical MRI scanner. Eleven individual AIFs (Ind-AIFs) met the criteria of expected enhancement pattern and were used to generate Avg-AIF. Tofts model was used to calculate pharmacokinetic DCE-MRI parameters. Bland-Altman plots and paired Student t-tests were used to describe significant differences between the pharmacokinetic parameters obtained from individual and average AIFs. Ind-AIFs obtained from eleven patients were used to calculate the Avg-AIF. No overall significant difference (bias) was observed for the transfer constant (K trans ) measured with Ind-AIFs compared to Avg-AIF (p = 0.20 for region-of-interest (ROI) analysis and p = 0.18 for histogram median analysis). Similarly, no overall significant difference was observed for interstitial fluid space volume fraction (v e ) measured with Ind-AIFs compared to Avg-AIF (p = 0.48 for ROI analysis and p = 0.93 for histogram median analysis). However, the Bland-Altman plot suggests that as K trans increases, the Ind-AIF estimates tend to become proportionally higher than the Avg-AIF estimates. We found no statistically significant overall bias in K trans or v e estimates derived from Avg-AIF, generated from a limited population, as compared with Ind-AIFs. However, further study is needed to determine whether calibration is needed across the range of K trans . The Avg-AIF obtained from a limited population may be used for pharmacokinetic modeling of DCE-MRI data in larger population studies with neck nodal metastases. Further validation of

  2. High Energy Resolution Hyperspectral X-Ray Imaging for Low-Dose Contrast-Enhanced Digital Mammography.

    Science.gov (United States)

    Pani, Silvia; Saifuddin, Sarene C; Ferreira, Filipa I M; Henthorn, Nicholas; Seller, Paul; Sellin, Paul J; Stratmann, Philipp; Veale, Matthew C; Wilson, Matthew D; Cernik, Robert J

    2017-09-01

    Contrast-enhanced digital mammography (CEDM) is an alternative to conventional X-ray mammography for imaging dense breasts. However, conventional approaches to CEDM require a double exposure of the patient, implying higher dose, and risk of incorrect image registration due to motion artifacts. A novel approach is presented, based on hyperspectral imaging, where a detector combining positional and high-resolution spectral information (in this case based on Cadmium Telluride) is used. This allows simultaneous acquisition of the two images required for CEDM. The approach was tested on a custom breast-equivalent phantom containing iodinated contrast agent (Niopam 150®). Two algorithms were used to obtain images of the contrast agent distribution: K-edge subtraction (KES), providing images of the distribution of the contrast agent with the background structures removed, and a dual-energy (DE) algorithm, providing an iodine-equivalent image and a water-equivalent image. The high energy resolution of the detector allowed the selection of two close-by energies, maximising the signal in KES images, and enhancing the visibility of details with the low surface concentration of contrast agent. DE performed consistently better than KES in terms of contrast-to-noise ratio of the details; moreover, it allowed a correct reconstruction of the surface concentration of the contrast agent in the iodine image. Comparison with CEDM with a conventional detector proved the superior performance of hyperspectral CEDM in terms of the image quality/dose tradeoff.

  3. Whole-body MRI, dynamic contrast-enhanced MRI, and diffusion-weighted imaging for the staging of multiple myeloma

    Energy Technology Data Exchange (ETDEWEB)

    Dutoit, Julie C.; Verstraete, Koenraad L. [Ghent University Hospital, Department of Radiology, Ghent (Belgium)

    2017-06-15

    Magnetic resonance imaging (MRI) is the most sensitive imaging technique for the detection of bone marrow infiltration, and has therefore recently been included in the new diagnostic myeloma criteria, as proposed by the International Myeloma Working Group. Nevertheless, conventional MRI only provides anatomical information and is therefore only of limited use in the response assessment of patients with multiple myeloma. The additional information from functional MRI techniques, such as diffusion-weighted imaging and dynamic contrast-enhanced MRI, can improve the detection rate of bone marrow infiltration and the assessment of response. This can further enhance the sensitivity and specificity of MRI in the staging of multiple myeloma patients. This article provides an overview of the technical aspects of conventional and functional MRI techniques with practical recommendations. It reviews the diagnostic performance, prognostic value, and role in therapy assessment in multiple myeloma and its precursor stages. (orig.)

  4. Contrast-enhanced Spectral Mammography: Modality-Specific Artifacts and Other Factors Which May Interfere with Image Quality.

    Science.gov (United States)

    Bhimani, Chandni; Li, Luna; Liao, Lydia; Roth, Robyn G; Tinney, Elizabeth; Germaine, Pauline

    2017-01-01

    Contrast-enhanced spectral mammography (CESM) uses full field digital mammography with the added benefit of intravenous contrast administration to significantly reduce false-positive and false-negative results and improve specificity while maintaining high sensitivity. For CESM to fulfill its purpose, one should be aware of possible artifacts and other factors which may interfere with image quality, and attention should be taken to minimize these factors. This pictorial demonstration will depict types of artifacts detected and other factors that interfere with image acquisition in our practice since CESM implementation. Many of the artifacts and other factors we have encountered while using CESM have simple solutions to resolve them. The illustrated artifacts and other factors interfering with image quality will serve as a useful reference to anyone using CESM. Copyright © 2017 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

  5. Vessel Wall Inflammation of Takayasu Arteritis Detected by Contrast-Enhanced Magnetic Resonance Imaging: Association with Disease Distribution and Activity.

    Directory of Open Access Journals (Sweden)

    Yoko Kato

    Full Text Available The assessment of the distribution and activity of vessel wall inflammation is clinically important in patients with Takayasu arteritis. Magnetic resonance imaging (MRI is a useful tool, but the clinical utility of late gadolinium enhancement (LGE in Takayasu arteritis has yet to be determined. The aim of the present study was to evaluate the utility of LGE in assessing vessel wall inflammation and disease activity in Takayasu arteritis.We enrolled 49 patients with Takayasu arteritis who had undergone 1.5 T MRI. Patients were divided into Active (n = 19 and Inactive disease (n = 30 groups. The distribution of vessel wall inflammation using angiography and LGE was assessed by qualitative analysis. In 79% and 63% of patients in Active and Inactive groups, respectively, greater distribution of vessel wall inflammation was observed with LGE than with conventional angiography. MRI values of pre- and post-contrast signal-to-noise ratios (SNR, SNR increment (post-SNR minus pre-SNR, pre- and post-contrast contrast-to-noise ratios (CNR, and CNR increment (post-CNR minus pre-CNR were evaluated at arterial wall sites with the highest signal intensity using quantitative analysis of post-contrast LGE images. No statistically significant differences in MRI parameters were observed between Active and Inactive groups. Contrast-enhanced MRI was unable to accurately detect active disease.Contrast-enhanced MRI has utility in detecting the distribution of vessel wall inflammation but has less utility in assessing disease activity in Takayasu arteritis.

  6. Role of MR imaging in the differentiation of benign and nonbenign intracranial meningiomas. The utility of contrast-enhanced T1-weighted images

    International Nuclear Information System (INIS)

    Tanaka, Yasunori; Matsuo, Michimasa

    1996-01-01

    The purpose of this study was to develop useful criteria for distinguishing nonbenign (atypical and malignant) primary intracranial meningiomas from their benign counterparts by using magnetic resonance imaging (MRI). To determine useful MRI findings for this purpose, 12 benign and five nonbenign meningiomas were retrospectively evaluated according to the following items: tumor signal intensity on plain T1-, T2- and proton density-weighted images, degree of perifocal edema on T2-weighted images, morphology of the tumor margin on contrast-enhanced T1-weighted images, presence of irregular nodule and/or mushrooming pattern on contrast-enhanced T1-weighted images, homogeneity of the tumor on contrast-enhanced T1-weighted images, and presence of marked skull destruction. Markedly irregular tumor margin, presence of irregular nodule and/or mushrooming pattern and markedly inhomogeneous enhancing pattern were significantly more frequent in nonbenign meningiomas. We defined these three MRI findings as nonbenign findings, and tried to categorize meningiomas by the number of nonbenign findings. It was found that 10 meningiomas with no or one nonbenign finding were benign lesions, of four meningiomas with two nonbenign findings two were benign lesions and two were nonbenign lesions, and three meningiomas with three nonbenign findings were nonbenign lesions. The two benign meningiomas with two nonbenign findings were accompanied by increased mitotic activity or brain invasion. Contrast-enhanced T1-weighted images were considered very useful in distinguishing benign and nonbenign meningiomas. (author)

  7. General Ultrasound Imaging

    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 General Ultrasound Ultrasound imaging ...

  8. An automatic respiratory gating method for the improvement of microcirculation evaluation: application to contrast-enhanced ultrasound studies of focal liver lesions

    Energy Technology Data Exchange (ETDEWEB)

    Mule, S; Kachenoura, N; Lucidarme, O; De Oliveira, A; Pellot-Barakat, C; Herment, A; Frouin, F, E-mail: Sebastien.Mule@gmail.com [INSERM UMR-S 678, 75634 Paris Cedex 13 (France)

    2011-08-21

    Contrast-enhanced ultrasound (CEUS), with the recent development of both contrast-specific imaging modalities and microbubble-based contrast agents, allows noninvasive quantification of microcirculation in vivo. Nevertheless, functional parameters obtained by modeling contrast uptake kinetics could be impaired by respiratory motion. Accordingly, we developed an automatic respiratory gating method and tested it on 35 CEUS hepatic datasets with focal lesions. Each dataset included fundamental mode and cadence contrast pulse sequencing (CPS) mode sequences acquired simultaneously. The developed method consisted in (1) the estimation of the respiratory kinetics as a linear combination of the first components provided by a principal components analysis constrained by a prior knowledge on the respiratory rate in the frequency domain, (2) the automated generation of two respiratory-gated subsequences from the CPS mode sequence by detecting end-of-inspiration and end-of-expiration phases from the respiratory kinetics. The fundamental mode enabled a more reliable estimation of the respiratory kinetics than the CPS mode. The k-means algorithm was applied on both the original CPS mode sequences and the respiratory-gated subsequences resulting in clustering maps and associated mean kinetics. Our respiratory gating process allowed better superimposition of manually drawn lesion contours on k-means clustering maps as well as substantial improvement of the quality of contrast uptake kinetics. While the quality of maps and kinetics was satisfactory in only 11/35 datasets before gating, it was satisfactory in 34/35 datasets after gating. Moreover, noise amplitude estimated within the delineated lesions was reduced from 62 {+-} 21 to 40 {+-} 10 (p < 0.01) after gating. These findings were supported by the low residual horizontal (0.44 {+-} 0.29 mm) and vertical (0.15 {+-} 0.16 mm) shifts found during manual motion correction of each respiratory-gated subsequence. The developed

  9. Multiphase contrast-enhanced magnetic resonance imaging features of Bacillus Calmette-Guerin-induced granulomatous prostatitis in five patients

    Energy Technology Data Exchange (ETDEWEB)

    Kawada, Hiroshi; Kanematsu, Masayuki; Goshima, Satoshi; Kondo, Hiroshi; Watanabe, Haruo; Noda, Yoshifumi; Tanahashi, Yukichi; Kawai, Nobuyuki; Hoshi, Hiroaki [Gifu University Hospital, Gifu (Japan)

    2015-04-15

    To evaluate the multiphase contrast-enhanced magnetic resonance (MR) imaging features of Bacillus Calmette-Guerin (BCG)-induced granulomatous prostatitis (GP). Magnetic resonance images obtained from five patients with histopathologically proven BCG-induced GP were retrospectively analyzed for tumor location, size, signal intensity on T2-weighted images (T2WI) and diffusion-weighted images (DWI), apparent diffusion coefficient (ADC) value, and appearance on gadolinium-enhanced multiphase images. MR imaging findings were compared with histopathological findings. Bacillus Calmette-Guerin-induced GP (size range, 9-40 mm; mean, 21.2 mm) were identified in the peripheral zone in all patients. The T2WI showed lower signal intensity compared with the normal peripheral zone. The DWIs demonstrated high signal intensity and low ADC values (range, 0.44-0.68 x 10(-3) mm2/sec; mean, 0.56 x 10(-3) mm2/sec), which corresponded to GP. Gadolinium-enhanced multiphase MR imaging performed in five patients showed early and prolonged ring enhancement in all cases of GP. Granulomatous tissues with central caseation necrosis were identified histologically, which corresponded to ring enhancement and a central low intensity area on gadolinium-enhanced MR imaging. The findings on T2WI, DWI, and gadolinium-enhanced images became gradually obscured with time. Bacillus Calmette-Guerin-induced GP demonstrates early and prolonged ring enhancement on gadolinium-enhanced MR imaging which might be a key finding to differentiate it from prostate cancer.

  10. Phase-contrast enhanced mammography: A new diagnostic tool for breast imaging

    International Nuclear Information System (INIS)

    Wang Zhentian; Thuering, Thomas; David, Christian; Roessl, Ewald; Trippel, Mafalda; Kubik-Huch, Rahel A.; Singer, Gad; Hohl, Michael K.; Hauser, Nik; Stampanoni, Marco

    2012-01-01

    Phase contrast and scattering-based X-ray imaging can potentially revolutionize the radiological approach to breast imaging by providing additional and complementary information to conventional, absorption-based methods. We investigated native, non-fixed whole breast samples using a grating interferometer with an X-ray tube-based configuration. Our approach simultaneously recorded absorption, differential phase contrast and small-angle scattering signals. The results show that this novel technique - combined with a dedicated image fusion algorithm - has the potential to deliver enhanced breast imaging with complementary information for an improved diagnostic process.

  11. Phase-contrast enhanced mammography: A new diagnostic tool for breast imaging

    Energy Technology Data Exchange (ETDEWEB)

    Wang Zhentian; Thuering, Thomas; David, Christian; Roessl, Ewald; Trippel, Mafalda; Kubik-Huch, Rahel A.; Singer, Gad; Hohl, Michael K.; Hauser, Nik; Stampanoni, Marco [Swiss Light Source, Paul Scherrer Institut, 5232 Villigen (Switzerland); Laboratory for Micro and Nanotechnology, Paul Scherrer Institut, 5232 Villigen (Switzerland); Philips Technologie GmbH, Roentgenstrasse 24, 22335 Hamburg (Germany); Institute of Pathology, Kantonsspital Baden, 5404 Baden (Switzerland); Department of Radiology, Kantonsspital Baden, 5404 Baden (Switzerland); Institute of Pathology, Kantonsspital Baden, 5404 Baden (Switzerland); Department of Gynecology and Obstetrics, Interdisciplinary Breast Center Baden, Kantonsspital Baden, 5404 Baden (Switzerland); Swiss Light Source, Paul Scherrer Institut, 5232 Villigen, Switzerland and Institute for Biomedical Engineering, University and ETH Zuerich, 8092 Zuerich (Switzerland)

    2012-07-31

    Phase contrast and scattering-based X-ray imaging can potentially revolutionize the radiological approach to breast imaging by providing additional and complementary information to conventional, absorption-based methods. We investigated native, non-fixed whole breast samples using a grating interferometer with an X-ray tube-based configuration. Our approach simultaneously recorded absorption, differential phase contrast and small-angle scattering signals. The results show that this novel technique - combined with a dedicated image fusion algorithm - has the potential to deliver enhanced breast imaging with complementary information for an improved diagnostic process.

  12. Detection of intracardiac shunts with contrast-enhanced dynamic MR imaging

    International Nuclear Information System (INIS)

    Manning, W.J.; Atkinson, D.J.; Parker, J.A.; Edelman, R.R.

    1990-01-01

    This paper reports on ultrafast MR imaging with bolus administration of Gd-DTPA used to detect intracardiac shunts. Ten patients who had recently undergone cardiac catheterization or first-pass radionuclide evaluation were selected for study. These included five patients without intracardiac shunts and five patients with shunts (three with atrial septal defect, two with ventricular septal defect). Resting four-chamber cardiac images were obtained during intravenous injection of Gd-DTPA (0.02 mmol/kg) with an ultrafast, T1-weighted sequence. Images were acquired over 380 msec, with repetitive images obtained with each QRS for 50 beats. In addition, standard MR cine examinations were performed

  13. Early evaluation of irradiated parotid glands with intravoxel incoherent motion MR imaging: correlation with dynamic contrast-enhanced MR imaging

    International Nuclear Information System (INIS)

    Zhou, Nan; Chu, Chen; Dou, Xin; Li, Ming; Liu, Song; Zhu, Lijing; Liu, Baorui; Guo, Tingting; Chen, Weibo; He, Jian; Yan, Jing; Zhou, Zhengyang; Yang, Xiaofeng; Liu, Tian

    2016-01-01

    Radiation-induced parotid damage is one of the most common complications in patients with nasopharyngeal carcinoma (NPC) undergoing radiotherapy (RT). Intravoxel incoherent motion (IVIM) magnetic resonance (MR) imaging has been reported for evaluating irradiated parotid damage. However, the changes of IVIM perfusion-related parameters in irradiated parotid glands have not been confirmed by conventional perfusion measurements obtained from dynamic contrast-enhanced (DCE) MR imaging. The purposes of this study were to monitor radiation-induced parotid damage using IVIM and DCE MR imaging and to investigate the correlations between changes of these MR parameters. Eighteen NPC patients underwent bilateral parotid T1-weighted, IVIM and DCE MR imaging pre-RT (2 weeks before RT) and post-RT (4 weeks after RT). Parotid volume; IVIM MR parameters, including apparent diffusion coefficient (ADC), pure diffusion coefficient (D), pseudo-diffusion coefficient (D*), and perfusion fraction (f); and DCE MR parameters, including maximum relative enhancement (MRE), time to peak (TTP), Wash in Rate, and the degree of xerostomia were recorded. Correlations of parotid MR parameters with mean radiation dose, atrophy rate and xerostomia degree, as well as the relationships between IVIM and DCE MR parameters, were investigated. From pre-RT to post-RT, all of the IVIM and DCE MR parameters increased significantly (p < 0.001 for ADC, D, f, MRE, Wash in Rate; p = 0.024 for D*; p = 0.037 for TTP). Change rates of ADC, f and MRE were negatively correlated with atrophy rate significantly (all p < 0.05). Significant correlations were observed between the change rates of D* and MRE (r = 0.371, p = 0.026) and between the change rates of D* and TTP (r = 0.396, p = 0.017). The intra- and interobserver reproducibility of IVIM and DCE MR parameters was good to excellent (intraclass correlation coefficient, 0.633–0.983). Early radiation-induced changes of parotid glands could be evaluated by IVIM and

  14. Comparison of Background Parenchymal Enhancement at Contrast-enhanced Spectral Mammography and Breast MR Imaging.

    Science.gov (United States)

    Sogani, Julie; Morris, Elizabeth A; Kaplan, Jennifer B; D'Alessio, Donna; Goldman, Debra; Moskowitz, Chaya S; Jochelson, Maxine S

    2017-01-01

    Purpose To assess the extent of background parenchymal enhancement (BPE) at contrast material-enhanced (CE) spectral mammography and breast magnetic resonance (MR) imaging, to evaluate interreader agreement in BPE assessment, and to examine the relationships between clinical factors and BPE. Materials and Methods This was a retrospective, institutional review board-approved, HIPAA-compliant study. Two hundred seventy-eight women from 25 to 76 years of age with increased breast cancer risk who underwent CE spectral mammography and MR imaging for screening or staging from 2010 through 2014 were included. Three readers independently rated BPE on CE spectral mammographic and MR images with the ordinal scale: minimal, mild, moderate, or marked. To assess pairwise agreement between BPE levels on CE spectral mammographic and MR images and among readers, weighted κ coefficients with quadratic weights were calculated. For overall agreement, mean κ values and bootstrapped 95% confidence intervals were calculated. The univariate and multivariate associations between BPE and clinical factors were examined by using generalized estimating equations separately for CE spectral mammography and MR imaging. Results Most women had minimal or mild BPE at both CE spectral mammography (68%-76%) and MR imaging (69%-76%). Between CE spectral mammography and MR imaging, the intrareader agreement ranged from moderate to substantial (κ = 0.55-0.67). Overall agreement on BPE levels between CE spectral mammography and MR imaging and among readers was substantial (κ = 0.66; 95% confidence interval: 0.61, 0.70). With both modalities, BPE demonstrated significant association with menopausal status, prior breast radiation therapy, hormonal treatment, breast density on CE spectral mammographic images, and amount of fibroglandular tissue on MR images (P spectral mammographic and MR images. © RSNA, 2016.

  15. Children's (Pediatric) Abdominal Ultrasound Imaging

    Medline Plus

    Full Text Available ... through blood vessels. Ultrasound imaging is a noninvasive medical test that helps physicians diagnose and treat medical conditions. Children's (pediatric) abdominal ultrasound imaging produces pictures ...

  16. General Ultrasound Imaging

    Medline Plus

    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 ...

  17. Abdominal ultrasound (image)

    Science.gov (United States)

    Abdominal ultrasound is a scanning technique used to image the interior of the abdomen. Like the X- ... use high frequency sound waves to produce an image and do not expose the individual to radiation. ...

  18. Lipid-based nanoparticles for contrast-enhanced MRI and molecular imaging

    NARCIS (Netherlands)

    Mulder, Willem J. M.; Strijkers, Gustav J.; van Tilborg, Geralda A. F.; Griffioen, Arjan W.; Nicolay, Klaas

    2006-01-01

    In the field of MR imaging and especially in the emerging field of cellular and molecular MR imaging, flexible strategies to synthesize contrast agents that can be manipulated in terms of size and composition and that can be easily conjugated with targeting ligands are required. Furthermore, the

  19. Characterization of the enhancing lesions on dynamic contrast enhanced magnetic resonance imaging in patients with interstitial mammoplasty

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Tae Yun [Department of Radiology, Seoul St. Mary' s Hospital, The Catholic University of Korea (Korea, Republic of); Kim, Sung Hun, E-mail: rad-ksh@catholic.ac.kr [Department of Radiology, Seoul St. Mary' s Hospital, The Catholic University of Korea (Korea, Republic of); Kang, Bong Joo [Department of Radiology, Seoul St. Mary' s Hospital, The Catholic University of Korea (Korea, Republic of); Kim, Hyeon Sook [Department of Radiology, St. Paul Hospital, The Catholic University of Korea (Korea, Republic of); Cha, Eun Suk [Department of Radiology, Ewha Womans University, School of Medicine, Mokdong Hospital (Korea, Republic of); Kim, Ji Youn [Department of Radiology, Yeouido St. Mary' s Hospital, The Catholic University of Korea (Korea, Republic of); Song, Byung Joo [Department of Surgery, Seoul St. Mary' s Hospital, The Catholic University of Korea, Seoul (Korea, Republic of)

    2013-12-01

    Purpose: The purpose of this study was to categorize the morphologic and kinetic features of enhancing lesions in breasts with interstitial mammoplasty using dynamic contrast-enhanced magnetic resonance imaging and to assess factors predictive of breast cancer. Materials and methods: We retrospectively reviewed the clinical and radiological data of 21 enhancing lesions in 19 patients with interstitial mammoplasty, who underwent breast magnetic resonance imaging and biopsy or an operation in our hospital from September 2008 to July 2012. These lesions were sorted by morphological and kinetic features and final assessment category according to the BI-RADS lexicon. Results: Nine cases were confirmed to be ductal carcinoma in situ (n = 2) and invasive ductal carcinoma (n = 7), and the remaining 12 cases were fibrocystic disease (n = 2), fibroadenoma (n = 2), fat necrosis (n = 1), foreign body granuloma (n = 3) and silicone mastitis (n = 1). Common features of malignancy included irregular shape (50.0%), spiculated margins (75.0%), heterogeneous enhancement (50.0%) and type III kinetic pattern (87.5%). The correlations of margins and kinetic curve pattern with benignity and malignancy approached statistical significance (p = 0.02, respectively). We found no correlation for shape (p = 0.33) or internal enhancement (p = 0.42) between lesion types. The malignancy rate of enhancing lesions was 42.8% (9/21). The sensitivity and specificity of dynamic contrast-enhanced magnetic resonance imaging were 100% and 16.67%, respectively. The positive predictive value, negative predictive value and accuracy of magnetic resonance imaging were 47.38%, 100% and 52.38%. Overall inter-observer agreement for the kinetic curve pattern was good (κ = 0.67). Moderate agreement was seen in describing the shape, margin, enhancement and assessing the final category (κ = 0.59, 0.46, 0.58 and 0.49, respectively). Conclusion: Dynamic contrast-enhanced magnetic resonance imaging had a high

  20. Characterization of the enhancing lesions on dynamic contrast enhanced magnetic resonance imaging in patients with interstitial mammoplasty

    International Nuclear Information System (INIS)

    Kim, Tae Yun; Kim, Sung Hun; Kang, Bong Joo; Kim, Hyeon Sook; Cha, Eun Suk; Kim, Ji Youn; Song, Byung Joo

    2013-01-01

    Purpose: The purpose of this study was to categorize the morphologic and kinetic features of enhancing lesions in breasts with interstitial mammoplasty using dynamic contrast-enhanced magnetic resonance imaging and to assess factors predictive of breast cancer. Materials and methods: We retrospectively reviewed the clinical and radiological data of 21 enhancing lesions in 19 patients with interstitial mammoplasty, who underwent breast magnetic resonance imaging and biopsy or an operation in our hospital from September 2008 to July 2012. These lesions were sorted by morphological and kinetic features and final assessment category according to the BI-RADS lexicon. Results: Nine cases were confirmed to be ductal carcinoma in situ (n = 2) and invasive ductal carcinoma (n = 7), and the remaining 12 cases were fibrocystic disease (n = 2), fibroadenoma (n = 2), fat necrosis (n = 1), foreign body granuloma (n = 3) and silicone mastitis (n = 1). Common features of malignancy included irregular shape (50.0%), spiculated margins (75.0%), heterogeneous enhancement (50.0%) and type III kinetic pattern (87.5%). The correlations of margins and kinetic curve pattern with benignity and malignancy approached statistical significance (p = 0.02, respectively). We found no correlation for shape (p = 0.33) or internal enhancement (p = 0.42) between lesion types. The malignancy rate of enhancing lesions was 42.8% (9/21). The sensitivity and specificity of dynamic contrast-enhanced magnetic resonance imaging were 100% and 16.67%, respectively. The positive predictive value, negative predictive value and accuracy of magnetic resonance imaging were 47.38%, 100% and 52.38%. Overall inter-observer agreement for the kinetic curve pattern was good (κ = 0.67). Moderate agreement was seen in describing the shape, margin, enhancement and assessing the final category (κ = 0.59, 0.46, 0.58 and 0.49, respectively). Conclusion: Dynamic contrast-enhanced magnetic resonance imaging had a high

  1. Photoelectron and x-ray holography by contrast: enhancing image quality and dimensionality

    Energy Technology Data Exchange (ETDEWEB)

    Fadley, C.S.; Zhao, L. [Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Department of Physics, University of California, Davis, CA (United States); Hove, M.A. van [Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Department of Physics, University of California, Davis, CA (United States); Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Kaduwela, A.; Marchesini, S. [Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Omori, S. [Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Institute of Industrial Science, University of Tokyo, Tokyo (Japan); Sony Corporation Semiconductor Network Company, Asahi-cho, Atsugi, Kanagawa (Japan)

    2001-11-26

    Three forms of electron or x-ray holography 'by contrast' are discussed: they all exploit small changes in diffraction conditions to improve image quality and/or extract additional information. Spin-polarized photoelectron holography subtracts spin-down from spin-up holograms so as to image the relative orientations of atomic magnetic moments around an emitter atom. Differential photoelectron holography subtracts holograms taken at slightly different energies so as to overcome the forward-scattering problem that normally degrades the three-dimensional imaging of atoms, particularly for emitter atoms that are part of a bulk substrate environment. Resonant x-ray fluorescence holography also subtracts holograms at slightly different energies, these being chosen above and below an absorption edge of a constituent atom, thus allowing the selective imaging of that type of atom, or what has been referred to as imaging 'in true colour'. (author)

  2. Phase contrast enhanced high resolution X-ray imaging and tomography of soft tissue

    International Nuclear Information System (INIS)

    Jakubek, Jan; Granja, Carlos; Dammer, Jiri; Hanus, Robert; Holy, Tomas; Pospisil, Stanislav; Tykva, Richard; Uher, Josef; Vykydal, Zdenek

    2007-01-01

    A tabletop system for digital high resolution and high sensitivity X-ray micro-radiography has been developed for small-animal and soft-tissue imaging. The system is based on a micro-focus X-ray tube and the semiconductor hybrid position sensitive Medipix2 pixel detector. Transmission radiography imaging, conventionally based only on absorption, is enhanced by exploiting phase-shift effects induced in the X-ray beam traversing the sample. Phase contrast imaging is realized by object edge enhancement. DAQ is done by a novel fully integrated USB-based readout with online image generation. Improved signal reconstruction techniques make use of advanced statistical data analysis, enhanced beam hardening correction and direct thickness calibration of individual pixels. 2D and 3D micro-tomography images of several biological samples demonstrate the applicability of the system for biological and medical purposes including in-vivo and time dependent physiological studies in the life sciences

  3. Contrast-enhanced MR imaging monitoring of acute tumor response to chemotherapy

    International Nuclear Information System (INIS)

    Ranney, D.F.; Cohen, J.M.; Antich, P.P.; Endman, W.A.; Kulkarni, P.; Weinreb, J.C.; Giovanella, B.

    1987-01-01

    Treatment responses of human malignant melanomas were monitored at millimeter resolution in athymic mice by injecting a new polymeric contrast agent, Gd-DTPA-dextran (0.1 mmol Gd/kg, intravenously). Proton MR imaging (0.35 T, spin-echo, repetition time = 0.5 second, echo time = 50 msec) was performed 30 hours after administering diphtheria toxin. Pre-contrast medium images revealed only homogeneous intermediate-intensity tumor masses. Post-contrast medium images of untreated (viable) tumors demonstrated 32% enhancement throughout the entire mass. Post-contrast medium images of toxin-treated tumors revealed marked enhancement (65%) of the histologically viable outer rims, lesser enhancement (38%) of heavily damaged subregions, and no enhancement of dead tumor. These acute, contrast medium-enhanced MR images accurately identified tumor subregions that survived for longer than one week

  4. Contrast-enhanced helical CT of the pancreas. Optimal timing of imaging for pancreatic tumor evaluation

    International Nuclear Information System (INIS)

    Koide, Kazuki; Sekiguchi, Ryuzo

    2001-01-01

    We performed three-phase helical CT in patients suspected pancreatic tumors and investigated the optimal timing of imaging for evaluation of the pancreatic mass. The pancreatic-phase was superior in detecting pancreatic tumors, including islet cell tumors that may show strong enhancement. However, portal vein-phase imaging was also superior in 16.7% of our patients. Taking into account examination for hepatic metastasis, helical CT of any pancreatic tumor should include images obtained in the pancreatic and portal vein phases. (author)

  5. Mammography combined with breast dynamic contrast-enhanced-magnetic resonance imaging for the diagnosis of early breast cancer

    Institute of Scientific and Technical Information of China (English)

    Yakun He; Guohui Xu; Jin Ren; Bin Feng; Xiaolei Dong; Hao Lu; Changjiu He

    2016-01-01

    Objective The aim of this study was to investigate the application of mammography combined with breast dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) for the diagnosis of early breast cancer. Methods Mammography and DCE-MRI were performed for 120 patients with breast cancer (malignant, 102; benign; 18). Results The sensitivity of mammography for early diagnosis of breast cancer was 66.67%, specificity was 77.78%, and accuracy was 68.33%. The sensitivity of MRI for early diagnosis of breast cancer was 94.12%, specificity was 88.89%, and accuracy was 93.33%. However, the sensitivity of mammography combined with DCE-MRI volume imaging with enhanced water signal (VIEWS) scanning for early diagnosis of breast cancer was 97.06%, specificity was 94.44%, and accuracy was 96.67%. Conclusion Mammography combined with DCE-MRI increased the sensitivity, specificity, and accuracy of diagnosing early breast cancer.

  6. Enhancement of Edge-based Image Quality Measures Using Entropy for Histogram Equalization-based Contrast Enhancement Techniques

    Directory of Open Access Journals (Sweden)

    H. T. R. Kurmasha

    2017-12-01

    Full Text Available An Edge-based image quality measure (IQM technique for the assessment of histogram equalization (HE-based contrast enhancement techniques has been proposed that outperforms the Absolute Mean Brightness Error (AMBE and Entropy which are the most commonly used IQMs to evaluate Histogram Equalization based techniques, and also the two prominent fidelity-based IQMs which are Multi-Scale Structural Similarity (MSSIM and Information Fidelity Criterion-based (IFC measures. The statistical evaluation results show that the Edge-based IQM, which was designed for detecting noise artifacts distortion, has a Person Correlation Coefficient (PCC > 0.86 while the others have poor or fair correlation to human opinion, considering the Human Visual Perception (HVP. Based on HVP, this paper propose an enhancement to classic Edge-based IQM by taking into account the brightness saturation distortion which is the most prominent distortion in HE-based contrast enhancement techniques. It is tested and found to have significantly well correlation (PCC > 0.87, Spearman rank order correlation coefficient (SROCC > 0.92, Root Mean Squared Error (RMSE < 0.1054, and Outlier Ratio (OR = 0%.

  7. A prospective study on contrast-enhanced magnetic resonance imaging of testicular lesions: distinctive features of Leydig cell tumours

    International Nuclear Information System (INIS)

    Manganaro, Lucia; Vinci, Valeria; Saldari, Matteo; Bernardo, Silvia; Cantisani, Vito; Catalano, Carlo; Pozza, Carlotta; Gianfrilli, Daniele; Pofi, Riccardo; Lenzi, Andrea; Isidori, Andrea M.; Scialpi, Michele

    2015-01-01

    Up to 20 % of incidentally found testicular lesions are benign Leydig cell tumours (LCTs). This study evaluates the role of contrast-enhanced magnetic resonance imaging (MRI) in the identification of LCTs in a large prospective cohort study. We enrolled 44 consecutive patients with at least one solid non-palpable testicular lesion who underwent scrotal MRI. Margins of the lesions, signal intensity and pattern of wash-in and wash-out were analysed by two radiologists. The frequency distribution of malignant and benign MRI features in the different groups was compared by using the chi-squared or Fisher's exact test. Sensitivity, specificity, positive and negative predictive value, and diagnostic accuracy were calculated. The sensitivity of scrotal MRI to diagnose LCTs was 89.47 % with 95.65 % specificity; sensitivity for malignant lesions was 95.65 % with 80.95 % specificity. A markedly hypointense signal on T2-WI, rapid and marked wash-in followed by a prolonged washout were distinctive features significantly associated with LCTs. Malignant lesions were significantly associated with blurred margins, weak hypointense signal on T2-WI,and weak and progressive wash-in. The overall diagnostic accuracy was 93 %. LCTs have distinctive contrast-enhanced MRI features that allow the differential diagnosis of incidental testicular lesions. (orig.)

  8. A prospective study on contrast-enhanced magnetic resonance imaging of testicular lesions: distinctive features of Leydig cell tumours

    Energy Technology Data Exchange (ETDEWEB)

    Manganaro, Lucia; Vinci, Valeria; Saldari, Matteo; Bernardo, Silvia; Cantisani, Vito; Catalano, Carlo [Sapienza University of Rome, Department of Radiology, Rome (Italy); Pozza, Carlotta; Gianfrilli, Daniele; Pofi, Riccardo; Lenzi, Andrea; Isidori, Andrea M. [Sapienza University of Rome, Department of Experimental Medicine, Rome (Italy); Scialpi, Michele [Perugia University, S. Maria della Misericordia Hospital, Department of Surgical and Biomedical Sciences, Division of Radiology 2, Perugia (Italy)

    2015-12-15

    Up to 20 % of incidentally found testicular lesions are benign Leydig cell tumours (LCTs). This study evaluates the role of contrast-enhanced magnetic resonance imaging (MRI) in the identification of LCTs in a large prospective cohort study. We enrolled 44 consecutive patients with at least one solid non-palpable testicular lesion who underwent scrotal MRI. Margins of the lesions, signal intensity and pattern of wash-in and wash-out were analysed by two radiologists. The frequency distribution of malignant and benign MRI features in the different groups was compared by using the chi-squared or Fisher's exact test. Sensitivity, specificity, positive and negative predictive value, and diagnostic accuracy were calculated. The sensitivity of scrotal MRI to diagnose LCTs was 89.47 % with 95.65 % specificity; sensitivity for malignant lesions was 95.65 % with 80.95 % specificity. A markedly hypointense signal on T2-WI, rapid and marked wash-in followed by a prolonged washout were distinctive features significantly associated with LCTs. Malignant lesions were significantly associated with blurred margins, weak hypointense signal on T2-WI,and weak and progressive wash-in. The overall diagnostic accuracy was 93 %. LCTs have distinctive contrast-enhanced MRI features that allow the differential diagnosis of incidental testicular lesions. (orig.)

  9. Hybrid imaging with contrast enhanced CT scan: A nuclear physician's point of view

    International Nuclear Information System (INIS)

    Houzard, C.; Tychyj-Pinel, C.; Defez, D.; Valette, P.J.; Giammarile, F.; Houzard, C.; Valette, P.J.; Giammarile, F.

    2010-01-01

    The ongoing development of hybrid imaging, with physical association of CT scan and PET or SPECT scan, allows integrating morphological and functional information on a single exam. This important technological evolution changes diagnostic and therapeutic strategy in a major manner, essentially in oncology. The possibility to inject intravenously iodinated contrast media in order to enhance CT image contrast is still a controversial question in France. We present our experience in this domain by approaching technical problems and diagnostic advantages. (authors)

  10. A novel technique of contrast-enhanced optical coherence tomography imaging in evaluation of clearance of lipids in human tears.

    Science.gov (United States)

    Napoli, Pietro Emanuele; Coronella, Franco; Satta, Giovanni Maria; Fossarello, Maurizio

    2014-01-01

    The aim of this work was to gather preliminary data in different conditions of healthy eyes, aqueous tear deficient dry eyes, obstructive meibomian gland disease (MGD) and non-obvious obstructive MGD (NOMGD) individuals, using a new, contrast-enhanced optical coherence tomography (OCT) imaging method to evaluate the clearance of lipids in human tears. Eighty-two adult patients presenting with complaints of ocular irritation were studied for abnormalities of the ocular surface and classified as healthy (n = 21), aqueous tear deficient dry eyes (n = 20), obstructive MGD (n = 15) and NOMGD (n = 26) individuals. A lipid-based tracer, containing an oil-in-water emulsion, was used to obtain an enhanced OCT imaging of the lower tear meniscus. After instillation, a dramatic initial increase of reflectivity of the lower tear meniscus was detected by OCT, followed by a decay back to baseline values over time. Based on this finding, the clearance of lipids was measured in real-time by Fourier-domain anterior segment OCT. The differences in the clearance of lipids among the four groups as well as the correlations between symptom questionnaire score, standardized visual scale test, fluorescein break-up time, ocular surface fluorescein staining score, Schirmer I test scores were found to be statistically significant. The individual areas under the curve of the clearance of lipids calculated by the receiver operating characteristic curve technique ranged from 0.66 to 0.98, suggesting reliable sensitivity and specificity of lipid-enhanced OCT imaging. This new technique of contrast-enhanced OCT imaging of the tear film following lipid-based tracer instillation provides a measure of the clearance of lipids. The quantitative values found are in agreement with other methods of evaluation of the lacrimal system. An improvement of the clinician's ability in the diagnosis and understanding of abnormalities of the ocular surface may be achieved by this simple approach.

  11. Contrast-enhanced dynamic MR imaging of parasellar tumor using fast spin-echo sequence

    International Nuclear Information System (INIS)

    Kusunoki, Katsusuke; Ohue, Shiro; Ichikawa, Haruhisa; Saito, Masahiro; Sadamoto, Kazuhiko; Sakaki, Saburo; Miki, Hitoshi.

    1995-01-01

    We have applied a new dynamic MRI technique that uses a fast spin-echo sequence to parasellar tumors. This sequence has less susceptible effect and better spatial resolution than a gradient echo sequence, providing faster images than a short spin-echo sequence does. Image was obtained in the coronal or sagittal plane using a 1.5T clinical MRI system, and then, dynamic MR images were acquired every 10 to 20 sec after administration of Gd-DTPA (0.1 mmol/kg). The subjects were 12 patients (5 microadenomas, 5 macroadenomas and 2 Rathke's cleft cysts) and 5 normal volunteers. As for volunteers, the cavernous sinus, pituitary stalk and posterior pituitary gland were contrasted on the first image, followed by visualization of the proximal portion adjacent to the junction of the infundibulum and the anterior pituitary gland, and finally by contrasting the distal portion of the anterior pituitary gland. There was a difference with respect to tumor contrast between microadenomas and macroadenomas. In the case of the macroadenomas, the tumor was contrasted at the same time as, or faster than the anterior pituitary gland, while with the microadenomas the tumor was enhanced later than the anterior pituitary gland. No enhancement with contrast medium was seen in Rathke's cleft cysts. In addition, it was possible to differentiate a recurrent tumor from a piece of muscle placed at surgery since the images obtained by the fast spin-echo sequence were clearer than those obtained by gradient echo sequence. (author)

  12. Contrast enhancement of microsphere-assisted super-resolution imaging in dark-field microscopy

    Science.gov (United States)

    Zhou, Yi; Tang, Yan; Deng, Qinyuan; Zhao, Lixin; Hu, Song

    2017-08-01

    We report a method of boosting the imaging contrast of microsphere-assisted super-resolution visualization by utilizing dark-field illumination (DFI). We conducted experiments on both 10-µm-diameter silica (SiO2) microspheres with refractive index n ∼ 1.46 under no and partial immersion in ethyl alcohol (n ∼ 1.36) and 20-µm-diameter barium titanate glass (BTG, n ∼ 1.9) microspheres with full immersion to show the super-resolution capability. We experimentally demonstrated that the imaging contrast and uniformity were extraordinarily improved in the DFI mode. The intensity profiles in the visualization also numerically confirm the enhanced sharpness for a better imaging quality when applying DFI.

  13. Contrast enhancement of fingerprint images using intuitionistic type II fuzzy set

    Directory of Open Access Journals (Sweden)

    Devarasan Ezhilmaran

    2015-04-01

    Full Text Available A novel contrast image enhancement of fingerprint images using intuitionistic type II fuzzy set theory is recommended in this work. The method of Hamacher T co-norm(S norm which generates a new membership function with the help of upper and lower membership function of type II fuzzy set. The finger print identification is one of the very few techniques employed in forensic science to aid criminal investigations in daily life, providing access control in financial security;-, visa related services, as well as others. Mostly fingerprint images are poorly illuminated and hardly visible, so it is necessary to enhance the input images. The enhancement is useful for authentication and matching. The fingerprint enhancement is vital for identifying and authenticating people by matching their fingerprints with the stored one in the database. The proposed enhancement of the intuitionistic type II fuzzy set theory results showed that it is more effective, especially, very useful for forensic science operations. The experimental results were compared with non-fuzzy, fuzzy, intuitionistic fuzzy and type II fuzzy methods in which the proposed method offered better results with good quality, less noise and low blur features.

  14. Diagnostic Utility of Contrast-enhanced 3D T1-weighted Imaging in Acute Cerebral Infarction Associated with Graves Disease.

    Science.gov (United States)

    Gon, Yasufumi; Sakaguchi, Manabu; Oyama, Naoki; Mochizuki, Hideki

    2017-02-01

    Graves disease is rarely complicated with cerebrovascular steno-occlusive diseases. Previous studies have suggested several hypotheses for this occurrence, including excess thyroid hormone, which stimulates the sympathetic nervous system, which in turn causes an abnormal hemodynamic response with consequent atherosclerotic changes, and antithyroid antibodies cause local vascular inflammation in patients with Graves disease. However, radiological findings of vasculitis in patients with Graves disease and cerebral infarction remain less known. We report the case of a 30-year-old Japanese woman with acute cerebral infarction due to vasculitis associated with Graves disease. She was admitted to our hospital with a 4-day history of intermittent transient dysarthria and limb shaking of the left leg when standing. Three weeks before admission, she went to a local hospital because of general malaise and was diagnosed with Graves disease. Neurological examination revealed paralytic dysarthria, left central facial nerve palsy, and left hemiparesis (manual muscle testing, 4 of 5). Blood examinations showed hyperthyroidism (thyroid-stimulating hormone ≤.010 µU/mL; free T3 ≥25.0 pg/mL; free T4 ≥8.0 ng/dL) and elevation of antithyroid antibody levels (thyroid peroxidase antibody, 87 IU/mL). The vessel wall of the right internal carotid artery was markedly enhanced on contrast-enhanced three-dimensional T1-weighted magnetic resonance imaging, suggesting vasculitis. Magnetic resonance angiography revealed right internal carotid artery occlusion after the branching ophthalmic artery. Arterial stenosis due to vasculitis was considered the cause of hemodynamic ischemic stroke. Vessel wall imaging such as high-resolution contrast-enhanced T1-weighted imaging seems useful for assessing the underlying mechanism of stroke in patients with Graves disease. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  15. Children's (Pediatric) Abdominal Ultrasound Imaging

    Medline Plus

    Full Text Available ... Physician Resources Professions Site Index A-Z Children's (Pediatric) Ultrasound - Abdomen Children’s (pediatric) ultrasound imaging of the ... abdomen using ultrasound. View full size with caption Pediatric Content Some imaging tests and treatments have special ...

  16. Children's (Pediatric) Abdominal Ultrasound Imaging

    Science.gov (United States)

    ... Physician Resources Professions Site Index A-Z Children's (Pediatric) Ultrasound - Abdomen Children’s (pediatric) ultrasound imaging of the ... abdomen using ultrasound. View full size with caption Pediatric Content Some imaging tests and treatments have special ...

  17. RGD-conjugated iron oxide magnetic nanoparticles for magnetic resonance imaging contrast enhancement and hyperthermia.

    Science.gov (United States)

    Zheng, S W; Huang, M; Hong, R Y; Deng, S M; Cheng, L F; Gao, B; Badami, D

    2014-03-01

    The purpose of this study was to develop a specific targeting magnetic nanoparticle probe for magnetic resonance imaging and therapy in the form of local hyperthermia. Carboxymethyl dextran-coated ultrasmall superparamagnetic iron oxide nanoparticles with carboxyl groups were coupled to cyclic arginine-glycine-aspartic peptides for integrin α(v)β₃ targeting. The particle size, magnetic properties, heating effect, and stability of the arginine-glycine-aspartic-ultrasmall superparamagnetic iron oxide were measured. The arginine-glycine-aspartic-ultrasmall superparamagnetic iron oxide demonstrates excellent stability and fast magneto-temperature response. Magnetic resonance imaging signal intensity of Bcap37 cells incubated with arginine-glycine-aspartic-ultrasmall superparamagnetic iron oxide was significantly decreased compared with that incubated with plain ultrasmall superparamagnetic iron oxide. The preferential uptake of arginine-glycine-aspartic-ultrasmall superparamagnetic iron oxide by target cells was further confirmed by Prussian blue staining and confocal laser scanning microscopy.

  18. Propagation stability of self-reconstructing Bessel beams enables contrast-enhanced imaging in thick media.

    Science.gov (United States)

    Fahrbach, Florian O; Rohrbach, Alexander

    2012-01-17

    Laser beams that can self-reconstruct their initial beam profile even in the presence of massive phase perturbations are able to propagate deeper into inhomogeneous media. This ability has crucial advantages for light sheet-based microscopy in thick media, such as cell clusters, embryos, skin or brain tissue or plants, as well as scattering synthetic materials. A ring system around the central intensity maximum of a Bessel beam enables its self-reconstruction, but at the same time illuminates out-of-focus regions and deteriorates image contrast. Here we present a detection method that minimizes the negative effect of the ring system. The beam's propagation stability along one straight line enables the use of a confocal line principle, resulting in a significant increase in image contrast. The axial resolution could be improved by nearly 100% relative to the standard light-sheet techniques using scanned Gaussian beams, while demonstrating self-reconstruction also for high propagation depths.

  19. Ossificans myositis: inflammatory changes and contrast enhancement of adjacent bone shown by MR imaging

    International Nuclear Information System (INIS)

    David, H.; Jolles, E.; Le Friant, G.; Silvestre, A.; Sarrazin, J.L.; Gordoliani, Y.S.

    1995-01-01

    The authors report a case of ossificans myositis, in which magnetic resonance imaging (MRI) showed inflammatory changes of the adjacent bone. T 1 weighted fat saturation sequence with gadolinium injection showed enhancement of medullary and cortical bone. This potentially mistaking pattern must be known, to avoid mis diagnosing with malignant osseous tumor, specially before achievement of the characteristic pattern of zonal maturation and its calcified rim. (authors). 15 refs., 6 figs

  20. The role of dynamic contrast-enhanced and diffusion weighted magnetic resonance imaging in the female pelvis

    Energy Technology Data Exchange (ETDEWEB)

    Sala, Evis, E-mail: es220@radiol.cam.ac.uk [University Department of Radiology, Box 218, Level 5, Addenbrooke' s Hospital, Hills Road, Cambridge CB2 0QQ (United Kingdom); Rockall, Andrea, E-mail: Andrea.Rockall@bartsandthelondon.nhs.uk [Department of Radiology, St Bartholomew' s Hospital, West Smithfield, London EC1A 7ED (United Kingdom); Rangarajan, Deepa, E-mail: rdrangarajan@googlemail.com [Department of Radiology, Box 218, Addenbrooke' s Hospital, Hills Road, Cambridge CB2 0QQ (United Kingdom); Kubik-Huch, Rahel A., E-mail: rahel.kubik@ksb.ch [Institute of Radiology, Department of Medical Services, Kantonsspital Baden Im Ergel, CH-5404 Baden (Switzerland)

    2010-12-15

    Functional imaging by means of dynamic multiphase contrast-enhanced magnetic resonance imaging (DCE-MRI) and diffusion weighted magnetic resonance imaging (DW-MRI) is now part of the standard imaging protocols for evaluation of the female pelvis. DCE-MRI and DW-MRI are important MR imaging techniques which enable the radiologist to move from morphological to functional assessment of diseases of the female pelvis. This is mainly due to the limitations of morphologic imaging, particularly in lesion characterization, accurate lymph node staging, assessment of tumour response and inability to differentiate post-treatment changes from tumour recurrence. DCE-MRI improves the accuracy of T2WI in staging of endometrial cancer. It also helps differentiate tumour recurrence from radiation fibrosis in patients with cervical cancer. DCE-MRI improves characterization of cystic adnexal lesions and detection of small peritoneal implants in patients with ovarian cancer. DW-MRI is valuable in preoperative staging of patients with endometrial and cervical cancer, especially in detection of extra-uterine disease. It does increase reader's confidence for detection of recurrent disease in gynaecological malignancies and improves detection of small peritoneal implants in patients with ovarian cancer. In this review article we give an overview of both DCE-MRI and DW-MRI techniques, concentrating on their main clinical application in the female pelvis, and present a practical approach of the added value of these techniques according to the main pathological conditions, highlighting the pearls and pitfalls of each technique.

  1. Dynamic contrast-enhanced MR imaging of the water fraction of normal bone marrow and diffuse bone marrow disease

    Energy Technology Data Exchange (ETDEWEB)

    Katsuya, Tomoo; Inoue, Tomio; Ishizaka, Hiroshi; Aoki, Jun; Endo, Keigo [Gunma Univ., Maebashi (Japan). School of Medicine

    2000-10-01

    To clarify the contrast-enhancement pattern of the normal hematopoietic element by isolating the signal of the water fraction in vertebral bone marrow and to investigate whether this approach can be used to characterize bone marrow pathology in several diffuse bone marrow diseases. Two groups were examined: 30 normal healthy volunteers and 19 patients with primary diffuse bone marrow disease (aplastic anemia [n=8], myelodysplastic syndrome (MDS) [n=5], chronic myelogenic leukemia (CML) [n=4], polycythemia vera [n=2]). Isolation of the signal of hematopoietic tissue was done by the chemical-shift misregistration effect. Twenty consecutive T1-weighted midsagittal lumber vertebral images were obtained immediately after the intravenous administration of Gd-DTPA of 0.1 mmol/kg body weight, and the pattern of the time-intensity curve, the peak contrast-enhancement (CE) ratio, and the washout rate (%/min) of bone marrow in normal volunteers were compared with those in patients suffering from primary diffuse bone marrow disease. The pattern of the time-intensity curve of patients with aplastic anemia showed a low peak value followed by a slow washout. However, the pattern of time-intensity curves in patients with MDS, CML, and polycythemia vera was similar to that of normal volunteers. The peak CE ratio of the water fraction in normal marrow ranged from 0.45 to 1.26 (mean {+-}S.D.: 0.87{+-}0.18). Patients with aplastic anemia showed an abnormally lower peak CE ratio of the water fraction (mean {+-}S.D.: 0.34{+-}0.19, p<0.0001). On the other hand, the peak CE ratio of the water fraction in patients with MDS was significantly higher than that of normal volunteers (mean {+-}S.D. 1.35{+-}0.39, p<0.05). In contrast, the peak CE ratio of patients with CML or polycythemia vera did not differ significantly from that of normal volunteers. The mean washout rate of patients with aplastic anemia was significantly lower than that of normal volunteers (mean {+-}S.D.: 3.50{+-}2.51 %/min

  2. Dynamic contrast-enhanced MR imaging of the water fraction of normal bone marrow and diffuse bone marrow disease

    International Nuclear Information System (INIS)

    Katsuya, Tomoo; Inoue, Tomio; Ishizaka, Hiroshi; Aoki, Jun; Endo, Keigo

    2000-01-01

    To clarify the contrast-enhancement pattern of the normal hematopoietic element by isolating the signal of the water fraction in vertebral bone marrow and to investigate whether this approach can be used to characterize bone marrow pathology in several diffuse bone marrow diseases. Two groups were examined: 30 normal healthy volunteers and 19 patients with primary diffuse bone marrow disease (aplastic anemia [n=8], myelodysplastic syndrome (MDS) [n=5], chronic myelogenic leukemia (CML) [n=4], polycythemia vera [n=2]). Isolation of the signal of hematopoietic tissue was done by the chemical-shift misregistration effect. Twenty consecutive T1-weighted midsagittal lumber vertebral images were obtained immediately after the intravenous administration of Gd-DTPA of 0.1 mmol/kg body weight, and the pattern of the time-intensity curve, the peak contrast-enhancement (CE) ratio, and the washout rate (%/min) of bone marrow in normal volunteers were compared with those in patients suffering from primary diffuse bone marrow disease. The pattern of the time-intensity curve of patients with aplastic anemia showed a low peak value followed by a slow washout. However, the pattern of time-intensity curves in patients with MDS, CML, and polycythemia vera was similar to that of normal volunteers. The peak CE ratio of the water fraction in normal marrow ranged from 0.45 to 1.26 (mean ±S.D.: 0.87±0.18). Patients with aplastic anemia showed an abnormally lower peak CE ratio of the water fraction (mean ±S.D.: 0.34±0.19, p<0.0001). On the other hand, the peak CE ratio of the water fraction in patients with MDS was significantly higher than that of normal volunteers (mean ±S.D. 1.35±0.39, p<0.05). In contrast, the peak CE ratio of patients with CML or polycythemia vera did not differ significantly from that of normal volunteers. The mean washout rate of patients with aplastic anemia was significantly lower than that of normal volunteers (mean ±S.D.: 3.50±2.51 %/min vs. 7.13±1

  3. An open source software for analysis of dynamic contrast enhanced magnetic resonance images: UMMPerfusion revisited.

    Science.gov (United States)

    Zöllner, Frank G; Daab, Markus; Sourbron, Steven P; Schad, Lothar R; Schoenberg, Stefan O; Weisser, Gerald

    2016-01-14

    Perfusion imaging has become an important image based tool to derive the physiological information in various applications, like tumor diagnostics and therapy, stroke, (cardio-) vascular diseases, or functional assessment of organs. However, even after 20 years of intense research in this field, perfusion imaging still remains a research tool without a broad clinical usage. One problem is the lack of standardization in technical aspects which have to be considered for successful quantitative evaluation; the second problem is a lack of tools that allow a direct integration into the diagnostic workflow in radiology. Five compartment models, namely, a one compartment model (1CP), a two compartment exchange (2CXM), a two compartment uptake model (2CUM), a two compartment filtration model (2FM) and eventually the extended Toft's model (ETM) were implemented as plugin for the DICOM workstation OsiriX. Moreover, the plugin has a clean graphical user interface and provides means for quality management during the perfusion data analysis. Based on reference test data, the implementation was validated against a reference implementation. No differences were found in the calculated parameters. We developed open source software to analyse DCE-MRI perfusion data. The software is designed as plugin for the DICOM Workstation OsiriX. It features a clean GUI and provides a simple workflow for data analysis while it could also be seen as a toolbox providing an implementation of several recent compartment models to be applied in research tasks. Integration into the infrastructure of a radiology department is given via OsiriX. Results can be saved automatically and reports generated automatically during data analysis ensure certain quality control.

  4. An open source software for analysis of dynamic contrast enhanced magnetic resonance images: UMMPerfusion revisited

    International Nuclear Information System (INIS)

    Zöllner, Frank G.; Daab, Markus; Sourbron, Steven P.; Schad, Lothar R.; Schoenberg, Stefan O.; Weisser, Gerald

    2016-01-01

    Perfusion imaging has become an important image based tool to derive the physiological information in various applications, like tumor diagnostics and therapy, stroke, (cardio-) vascular diseases, or functional assessment of organs. However, even after 20 years of intense research in this field, perfusion imaging still remains a research tool without a broad clinical usage. One problem is the lack of standardization in technical aspects which have to be considered for successful quantitative evaluation; the second problem is a lack of tools that allow a direct integration into the diagnostic workflow in radiology. Five compartment models, namely, a one compartment model (1CP), a two compartment exchange (2CXM), a two compartment uptake model (2CUM), a two compartment filtration model (2FM) and eventually the extended Toft’s model (ETM) were implemented as plugin for the DICOM workstation OsiriX. Moreover, the plugin has a clean graphical user interface and provides means for quality management during the perfusion data analysis. Based on reference test data, the implementation was validated against a reference implementation. No differences were found in the calculated parameters. We developed open source software to analyse DCE-MRI perfusion data. The software is designed as plugin for the DICOM Workstation OsiriX. It features a clean GUI and provides a simple workflow for data analysis while it could also be seen as a toolbox providing an implementation of several recent compartment models to be applied in research tasks. Integration into the infrastructure of a radiology department is given via OsiriX. Results can be saved automatically and reports generated automatically during data analysis ensure certain quality control

  5. An Efficient Method for Detection of Outliers in Tracer Curves Derived from Dynamic Contrast-Enhanced Imaging

    Directory of Open Access Journals (Sweden)

    Linning Ye

    2018-01-01

    Full Text Available Presence of outliers in tracer concentration-time curves derived from dynamic contrast-enhanced imaging can adversely affect the analysis of the tracer curves by model-fitting. A computationally efficient method for detecting outliers in tracer concentration-time curves is presented in this study. The proposed method is based on a piecewise linear model and implemented using a robust clustering algorithm. The method is noniterative and all the parameters are automatically estimated. To compare the proposed method with existing Gaussian model based and robust regression-based methods, simulation studies were performed by simulating tracer concentration-time curves using the generalized Tofts model and kinetic parameters derived from different tissue types. Results show that the proposed method and the robust regression-based method achieve better detection performance than the Gaussian model based method. Compared with the robust regression-based method, the proposed method can achieve similar detection performance with much faster computation speed.

  6. Dynamic Contrast-Enhanced MR Imaging of Renal Ischemia-Reperfusion Injury

    Energy Technology Data Exchange (ETDEWEB)

    Baik, Jun Hyun; Ahn, Myeong Im; Park, Young Ha; Chung, Soo Kyo [Catholic University, Seoul (Korea, Republic of)

    2010-02-15

    To evaluate the usefulness of magnetic resonance imaging (MRI) in a renal ischemia-reperfusion injury. Twenty-four rabbits were randomly divided into four groups, including a sham operated group (n=3). Renal ischemia was induced for 30 minutes (group 1), 60 minutes (group 2) and 120 minutes (group 3). MR imaging was performed before ischemia as well as one hour, 24 hours, and 72 hours after reperfusion. A 99mTc-dimercaptosuccinic acid (DMSA) scintigraphy was performed before ischemia, as well as 24 hours and 72 hours after reperfusion. The signal-to-noise ratio (SNR) on the T2WI, time-relative signal intensity (%RSI) curve on dynamic enhanced images, and relative left renal uptake (%) on DMSA scan were obtained and compared to the histologic findings. The SNR of the cortex on the T2WI changed significantly over the course of the reperfusion time (p<0.001), but was not significantly different among the ischemia groups. The area under the time-%RSI curve gradually decreased from cortex to inner medulla before ischemia, which was reversed and gradually increased after reperfusion. The areas under the time-%RSI curve of outer and inner medulla were significantly different among the ischemia groups (p=0.04, p=0.008). The relative renal uptake (%) of left kidney decreased significantly over the reperfusion time (p=0.03), and was also significantly different among the ischemia groups (p=0.005). Tubular cell necrosis was observed in 16 rabbits (76.2%). The histologic grades of group 3 were higher than those of group 1 and group 2 (p=0.002). Even in rabbits without tubular cell necrosis, the areas under the time-%RSI curves of the cortex, outer, and inner medulla after a 72 hour reperfusion time were significantly lower than those before ischemia (p=0.007, p=0.005, p=0.004). The results of this study suggest that dynamic enhanced MR imaging could be a useful tool for the evaluation of renal ischemia and reperfusion injury.

  7. Detection of eosinophilic myocarditis using contrast-enhanced magnetic resonance imaging: case report

    International Nuclear Information System (INIS)

    Takahashi, N.; Murakami, Y.; Shimada, T.; Kashima, Y.; Nakamura, K.; Inoue, S.-I.; Sugamori, T.; Katoh, H.; Ishibashi, Y.; Maruyama, R.

    2001-01-01

    Hypereosinophilic syndrome is characterized by idiopathic eosinophilia in the peripheral blood and multiorgan dysfunction secondary to mature eosinophil infiltration. It is essential to diagnose myocardial involvement in the early stage of the disease when active myocarditis due to cardiotoxic substances from eosinophils is still taking place, but clinical tools for the diagnosis of myocardial lesions in patients without overt cardiac dysfunction are not yet available. We present a case of successful detection of myocarditis due to hypereosinophilic syndrome by gadolinium-diethylenetriaminepentaascetic acid (Gd-DTPA) enhanced magnetic resonance imaging (MRI). (author)

  8. Detection of eosinophilic myocarditis using contrast-enhanced magnetic resonance imaging: case report

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, N.; Murakami, Y.; Shimada, T.; Kashima, Y.; Nakamura, K.; Inoue, S.-I.; Sugamori, T.; Katoh, H.; Ishibashi, Y. [Shimane Medical Univ., The Fourth Dept. of Internal Medicine, Izumo City, Shimane (Japan); Maruyama, R. [Shimane Medical Univ., Dept. of Laboratory Medicine, Izumo City, Shimane (Japan)

    2001-02-01

    Hypereosinophilic syndrome is characterized by idiopathic eosinophilia in the peripheral blood and multiorgan dysfunction secondary to mature eosinophil infiltration. It is essential to diagnose myocardial involvement in the early stage of the disease when active myocarditis due to cardiotoxic substances from eosinophils is still taking place, but clinical tools for the diagnosis of myocardial lesions in patients without overt cardiac dysfunction are not yet available. We present a case of successful detection of myocarditis due to hypereosinophilic syndrome by gadolinium-diethylenetriaminepentaascetic acid (Gd-DTPA) enhanced magnetic resonance imaging (MRI). (author)

  9. General Ultrasound Imaging

    Medline Plus

    Full Text Available ... to image by ultrasound because greater amounts of tissue attenuate (weaken) the sound waves as they pass deeper into the body and need to be returned to the transducer for analysis. Ultrasound has difficulty penetrating bone and, therefore, can only see the outer surface ...

  10. General Ultrasound Imaging

    Medline Plus

    Full Text Available ... women and their unborn babies. Ultrasound provides real-time imaging, making it a good tool for guiding minimally invasive procedures such as needle biopsies and fluid aspiration. Risks For standard diagnostic ultrasound , there are no known harmful effects on humans. top of page What are the ...

  11. Quantification of regional cerebral blood flow and volume with dynamic susceptibility contrast-enhanced MR imaging.

    Science.gov (United States)

    Rempp, K A; Brix, G; Wenz, F; Becker, C R; Gückel, F; Lorenz, W J

    1994-12-01

    Quantification of regional cerebral blood flow (rCBF) and volume (rCBV) with dynamic magnetic resonance (MR) imaging. After bolus administration of a paramagnetic contrast medium, rapid T2*-weighted gradient-echo images of two sections were acquired for the simultaneous creation of concentration-time curves in the brain-feeding arteries and in brain tissue. Absolute rCBF and rCBV values were determined for gray and white brain matter in 12 subjects with use of principles of the indicator dilution theory. The mean rCBF value in gray matter was 69.7 mL/min +/- 29.7 per 100 g tissue and in white matter, 33.6 mL/min +/- 11.5 per 100 g tissue; the average rCBV was 8.0 mL +/- 3.1 per 100 g tissue and 4.2 mL +/- 1.0 per 100 g tissue, respectively. An age-related decrease in rCBF and rCBV for gray and white matter was observed. Preliminary data demonstrate that the proposed technique allows the quantification of rCBF and rCBV. Although the results are in good agreement with data from positron emission tomography studies, further evaluation is needed to establish the validity of method.

  12. MR imaging of hepatic metastasis in patients with malignant melanoma: Evaluation of suspected lesions screened at contrast-enhanced CT

    International Nuclear Information System (INIS)

    Sofue, Keitaro; Tateishi, Ukihide; Tsurusaki, Masakatsu; Arai, Yasuaki; Yamazaki, Naoya; Sugimura, Kazuro

    2012-01-01

    Purpose: To evaluate the magnetic resonance (MR) imaging feature of suspected hepatic metastasis in patients with malignant melanoma which showed intermediate findings on screened contrast-enhanced computed tomography (CECT). Materials and methods: MR imaging was performed in 38 patients (22 men, 16 women; mean age, 58 years) whose CECT findings were intermediate. Hepatic metastases had been diagnosed on MR imaging in 23 of the 38 patients. Verification of hepatic metastasis was made by histological examination: ultrasonographic-guided needle biopsy (n = 3), autopsy (n = 3), and surgical resection (n = 1), or by an obvious progression in number and/or size of the lesions on follow-up MR imaging (n = 24). Two diagnostic radiologists reviewed MR images by consensus. The median follow-up duration was 14.2 months. Results: Abnormal findings were detected in 31 patients on MR images, and undetected in the remaining seven patients resulting in false-positive on CECT. The mean size of the lesion was 11.0 mm. False-positive results were obtained in two lesions which disappeared on follow-up MR imaging. In six patients, lesions were considered as hepatic cysts on MR images. As a result, a total of 35 hepatic metastases were detected on MR images. Of these, 18 patients demonstrated typical melanotic appearance on MR images which showed shortened T1 and T2 relaxation times, and five patients demonstrated atypical melanotic appearance. In 16 patients, extra-hepatic metastases were also developed. Conclusion: MR imaging could rule out hepatic metastasis in patients with malignant melanoma which showed intermediate findings on screened CECT, and could detect additional extra-hepatic metastases.

  13. Dynamic iterative beam hardening correction (DIBHC) in myocardial perfusion imaging using contrast-enhanced computed tomography.

    Science.gov (United States)

    Stenner, Philip; Schmidt, Bernhard; Allmendinger, Thomas; Flohr, Thomas; Kachelrie, Marc

    2010-06-01

    In cardiac perfusion examinations with computed tomography (CT) large concentrations of iodine in the ventricle and in the descending aorta cause beam hardening artifacts that can lead to incorrect perfusion parameters. The aim of this study is to reduce these artifacts by performing an iterative correction and by accounting for the 3 materials soft tissue, bone, and iodine. Beam hardening corrections are either implemented as simple precorrections which cannot account for higher order beam hardening effects, or as iterative approaches that are based on segmenting the original image into material distribution images. Conventional segmentation algorithms fail to clearly distinguish between iodine and bone. Our new algorithm, DIBHC, calculates the time-dependent iodine distribution by analyzing the voxel changes of a cardiac perfusion examination (typically N approximately 15 electrocardiogram-correlated scans distributed over a total scan time up to T approximately 30 s). These voxel dynamics are due to changes in contrast agent. This prior information allows to precisely distinguish between bone and iodine and is key to DIBHC where each iteration consists of a multimaterial (soft tissue, bone, iodine) polychromatic forward projection, a raw data comparison and a filtered backprojection. Simulations with a semi-anthropomorphic dynamic phantom and clinical scans using a dual source CT scanner with 2 x 128 slices, a tube voltage of 100 kV, a tube current of 180 mAs, and a rotation time of 0.28 seconds have been carried out. The uncorrected images suffer from beam hardening artifacts that appear as dark bands connecting large concentrations of iodine in the ventricle, aorta, and bony structures. The CT-values of the affected tissue are usually underestimated by roughly 20 HU although deviations of up to 61 HU have been observed. For a quantitative evaluation circular regions of interest have been analyzed. After application of DIBHC the mean values obtained deviate by

  14. Detection of early carious lesions using contrast enhancement with coherent light scattering (speckle imaging)

    International Nuclear Information System (INIS)

    Deana, A M; Jesus, S H C; Koshoji, N H; Bussadori, S K; Oliveira, M T

    2013-01-01

    Currently, dental caries still represent one of the chronic diseases with the highest prevalence and present in most countries. The interaction between light and teeth (absorption, scattering and fluorescence) is intrinsically connected to the constitution of the dental tissue. Decay induced mineral loss introduces a shift in the optical properties of the affected tissue; therefore, study of these properties may produce novel techniques aimed at the early diagnosis of carious lesions. Based on the optical properties of the enamel, we demonstrate the application of first-order spatial statistics in laser speckle imaging, allowing the detection of carious lesions in their early stages. A highlight of this noninvasive, non-destructive, real time and cost effective approach is that it allows a dentist to detect a lesion even in the absence of biofilm or moisture. (paper)

  15. Contrast-Enhanced Ultrasound Improves the Pathological Outcomes of US-Guided Core Needle Biopsy That Targets the Viable Area of Anterior Mediastinal Masses

    Directory of Open Access Journals (Sweden)

    Jian-hua Zhou

    2018-01-01

    Full Text Available Based on the option that ultrasound-guided core needle biopsy (US-CNB of the enhanced portion of anterior mediastinal masses (AMMs identified by contrast-enhanced ultrasound (CEUS would harvest viable tissue and benefit the histological diagnoses, a retrospective study was performed to elucidate the correlation between the prebiopsy CEUS and diagnostic yield of AMMs and found that CEUS potentially improved the diagnostic yield of AMMs compared with conventional US with a significant increase in the cellularity of samples. Furthermore, the marginal blood flow signals and absence of necrosis can predict the diagnostic yield of AMM. It was concluded that US-CNB of the viable part of AMMs, as verified by CEUS, was able to harvest sufficient tissue with more cellularity that could be used for ancillary studies and improve the diagnostic yield. And CEUS was recommended to those patients with AMMs undergoing repeated US-CNB, with the absence of marginal blood signals or presence of necrosis.

  16. Dual-energy contrast-enhanced breast tomosynthesis: optimization of beam quality for dose and image quality

    International Nuclear Information System (INIS)

    Samei, Ehsan; Saunders, Robert S Jr

    2011-01-01

    Dual-energy contrast-enhanced breast tomosynthesis is a promising technique to obtain three-dimensional functional information from the breast with high resolution and speed. To optimize this new method, this study searched for the beam quality that maximized image quality in terms of mass detection performance. A digital tomosynthesis system was modeled using a fast ray-tracing algorithm, which created simulated projection images by tracking photons through a voxelized anatomical breast phantom containing iodinated lesions. The single-energy images were combined into dual-energy images through a weighted log subtraction process. The weighting factor was optimized to minimize anatomical noise, while the dose distribution was chosen to minimize quantum noise. The dual-energy images were analyzed for the signal difference to noise ratio (SdNR) of iodinated masses. The fast ray-tracing explored 523 776 dual-energy combinations to identify which yields optimum mass SdNR. The ray-tracing results were verified using a Monte Carlo model for a breast tomosynthesis system with a selenium-based flat-panel detector. The projection images from our voxelized breast phantom were obtained at a constant total glandular dose. The projections were combined using weighted log subtraction and reconstructed using commercial reconstruction software. The lesion SdNR was measured in the central reconstructed slice. The SdNR performance varied markedly across the kVp and filtration space. Ray-tracing results indicated that the mass SdNR was maximized with a high-energy tungsten beam at 49 kVp with 92.5 μm of copper filtration and a low-energy tungsten beam at 49 kVp with 95 μm of tin filtration. This result was consistent with Monte Carlo findings. This mammographic technique led to a mass SdNR of 0.92 ± 0.03 in the projections and 3.68 ± 0.19 in the reconstructed slices. These values were markedly higher than those for non-optimized techniques. Our findings indicate that dual

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