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Sample records for endoscopic ultrasound elastography

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

    PubMed

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

    2016-08-01

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

  2. Endoscopic ultrasound elastography: Current status and future perspectives.

    PubMed

    Cui, Xin-Wu; Chang, Jian-Min; Kan, Quan-Cheng; Chiorean, Liliana; Ignee, Andre; Dietrich, Christoph F

    2015-12-21

    Elastography is a new ultrasound modality that provides images and measurements related to tissue stiffness. Endoscopic ultrasound (EUS) has played an important role in the diagnosis and management of numerous abdominal and mediastinal diseases. Elastography by means of EUS examination can assess the elasticity of tumors in the proximity of the digestive tract that are hard to reach with conventional transcutaneous ultrasound probes, such as pancreatic masses and mediastinal or abdominal lymph nodes, thus improving the diagnostic yield of the procedure. Results from previous studies have promised benefits for EUS elastography in the differential diagnosis of lymph nodes, as well as for assessing masses with pancreatic or gastrointestinal (GI) tract locations. It is important to mention that EUS elastography is not considered a modality that can replace biopsy. However, it may be a useful adjunct, improving the accuracy of EUS-fine needle aspiration biopsy (EUS-FNAB) by selecting the most suspicious area to be targeted. Even more, it may be useful for guiding further clinical management when EUS-FNAB is negative or inconclusive. In the present paper we will discuss the current knowledge of EUS elastography, including the technical aspects, along with its applications in the differential diagnosis between benign and malignant solid pancreatic masses and lymph nodes, as well as its aid in the differentiation between normal pancreatic tissues and chronic pancreatitis. Moreover, the emergent indication and future perspectives are summarized, such as the benefit of EUS elastography in EUS-guided fine needle aspiration biopsy, and its uses for characterization of lesions in liver, biliary tract, adrenal glands and GI tract.

  3. Endoscopic ultrasound in the diagnosis of acinar cell carcinoma of the pancreas: contrast-enhanced endoscopic ultrasound, endoscopic ultrasound elastography, and pathological correlation.

    PubMed

    Chantarojanasiri, Tanyaporn; Hirooka, Yoshiki; Kawashima, Hiroki; Ohno, Eizaburo; Yamamura, Takeshi; Funasaka, Kohei; Nakamura, Masanao; Miyahara, Ryoji; Ishigami, Masatoshi; Watanabe, Osamu; Nakaguro, Masato; Shimoyama, Yoshie; Nakamura, Shigeo; Goto, Hidemi

    2016-11-01

    We report a case series of five patients with pancreatic acinar cell carcinoma who received surgical treatment and compared the preoperative contrast-enhanced endoscopic ultrasound (EUS) and EUS elastography patterns with the surgical specimens. The contrast-enhanced EUS indicated vascular tumors with gradual enhancement in four patients and a hypovascular tumor in one patient. The elastography indicated an elastic score of 3 (hard lesion with softer border) in two patients and a score of 5 (hard lesion, which included the surrounding area) in two patients. In tumors with an elastic score of 5, the pathology exhibited abundant hyalinizing fibrous stroma or massive tumor invasion to the surrounding tissue. We concluded that acinar cell carcinoma of the pancreas has various patterns of EUS contrast-enhancement and elastography, depending on the pathologic phenotype.

  4. Endoscopic ultrasound in the diagnosis of acinar cell carcinoma of the pancreas: contrast-enhanced endoscopic ultrasound, endoscopic ultrasound elastography, and pathological correlation

    PubMed Central

    Chantarojanasiri, Tanyaporn; Hirooka, Yoshiki; Kawashima, Hiroki; Ohno, Eizaburo; Yamamura, Takeshi; Funasaka, Kohei; Nakamura, Masanao; Miyahara, Ryoji; Ishigami, Masatoshi; Watanabe, Osamu; Nakaguro, Masato; Shimoyama, Yoshie; Nakamura, Shigeo; Goto, Hidemi

    2016-01-01

    We report a case series of five patients with pancreatic acinar cell carcinoma who received surgical treatment and compared the preoperative contrast-enhanced endoscopic ultrasound (EUS) and EUS elastography patterns with the surgical specimens. The contrast-enhanced EUS indicated vascular tumors with gradual enhancement in four patients and a hypovascular tumor in one patient. The elastography indicated an elastic score of 3 (hard lesion with softer border) in two patients and a score of 5 (hard lesion, which included the surrounding area) in two patients. In tumors with an elastic score of 5, the pathology exhibited abundant hyalinizing fibrous stroma or massive tumor invasion to the surrounding tissue. We concluded that acinar cell carcinoma of the pancreas has various patterns of EUS contrast-enhancement and elastography, depending on the pathologic phenotype. PMID:27853750

  5. Real time endoscopic ultrasound elastography and strain ratio in the diagnosis of solid pancreatic lesions

    PubMed Central

    Okasha, Hussein; Elkholy, Shaimaa; El-Sayed, Ramy; Wifi, Mohamed-Naguib; El-Nady, Mohamed; El-Nabawi, Walid; El-Dayem, Waleed A; Radwan, Mohamed I; Farag, Ali; El-sherif, Yahya; Al-Gemeie, Emad; Salman, Ahmed; El-Sherbiny, Mohamed; El-Mazny, Ahmed; Mahdy, Reem E

    2017-01-01

    AIM To evaluate the accuracy of the elastography score combined to the strain ratio in the diagnosis of solid pancreatic lesions (SPL). METHODS A total of 172 patients with SPL identified by endoscopic ultrasound were enrolled in the study to evaluate the efficacy of elastography and strain ratio in differentiating malignant from benign lesions. The semi quantitative score of elastography was represented by the strain ratio method. Two areas were selected, area (A) representing the region of interest and area (B) representing the normal area. Area (B) was then divided by area (A). Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were calculated by comparing diagnoses made by elastography, strain ratio and final diagnoses. RESULTS SPL were shown to be benign in 49 patients and malignant in 123 patients. Elastography alone had a sensitivity of 99%, a specificity of 63%, and an accuracy of 88%, a PPV of 87% and an NPV of 96%. The best cut-off level of strain ratio to obtain the maximal area under the curve was 7.8 with a sensitivity of 92%, specificity of 77%, PPV of 91%, NPV of 80% and an accuracy of 88%. Another estimated cut off strain ratio level of 3.8 had a higher sensitivity of 99% and NPV of 96%, but with less specificity, PPV and accuracy 53%, 84% and 86%, respectively. Adding both elastography to strain ratio resulted in a sensitivity of 98%, specificity of 77%, PPV of 91%, NPV of 95% and accuracy of 92% for the diagnosis of SPL. CONCLUSION Combining elastography to strain ratio increases the accuracy of the differentiation of benign from malignant SPL. PMID:28932088

  6. Real time endoscopic ultrasound elastography and strain ratio in the diagnosis of solid pancreatic lesions.

    PubMed

    Okasha, Hussein; Elkholy, Shaimaa; El-Sayed, Ramy; Wifi, Mohamed-Naguib; El-Nady, Mohamed; El-Nabawi, Walid; El-Dayem, Waleed A; Radwan, Mohamed I; Farag, Ali; El-Sherif, Yahya; Al-Gemeie, Emad; Salman, Ahmed; El-Sherbiny, Mohamed; El-Mazny, Ahmed; Mahdy, Reem E

    2017-08-28

    To evaluate the accuracy of the elastography score combined to the strain ratio in the diagnosis of solid pancreatic lesions (SPL). A total of 172 patients with SPL identified by endoscopic ultrasound were enrolled in the study to evaluate the efficacy of elastography and strain ratio in differentiating malignant from benign lesions. The semi quantitative score of elastography was represented by the strain ratio method. Two areas were selected, area (A) representing the region of interest and area (B) representing the normal area. Area (B) was then divided by area (A). Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were calculated by comparing diagnoses made by elastography, strain ratio and final diagnoses. SPL were shown to be benign in 49 patients and malignant in 123 patients. Elastography alone had a sensitivity of 99%, a specificity of 63%, and an accuracy of 88%, a PPV of 87% and an NPV of 96%. The best cut-off level of strain ratio to obtain the maximal area under the curve was 7.8 with a sensitivity of 92%, specificity of 77%, PPV of 91%, NPV of 80% and an accuracy of 88%. Another estimated cut off strain ratio level of 3.8 had a higher sensitivity of 99% and NPV of 96%, but with less specificity, PPV and accuracy 53%, 84% and 86%, respectively. Adding both elastography to strain ratio resulted in a sensitivity of 98%, specificity of 77%, PPV of 91%, NPV of 95% and accuracy of 92% for the diagnosis of SPL. Combining elastography to strain ratio increases the accuracy of the differentiation of benign from malignant SPL.

  7. Contrast-enhanced (endoscopic) ultrasound and endoscopic ultrasound elastography in gastrointestinal stromal tumors

    PubMed Central

    Ignee, Andre; Jenssen, Christian; Hocke, Michael; Dong, Yi; Wang, Wen-Ping; Cui, Xin-Wu; Woenckhaus, Matthias; Iordache, Sevastita; Saftoiu, Adrian; Schuessler, Gudrun; Dietrich, Christoph F.

    2017-01-01

    Background and Objectives: Gastrointestinal stromal tumors (GISTs) represent the largest group of subepithelial tumors (SET) of the upper gastrointestinal (GI) tract. They may show malignant behavior, in contrast to other SET. Endoscopic ultrasound (EUS) is frequently used to characterize SET. With the introduction of contrast-enhanced ultrasound (CEUS) into EUS (CE-EUS), distinct enhancement patterns can be detected. In the presented study, the characteristic features of CE-EUS in GIST are analyzed and compared with those of other SET. Materials and Methods: Consecutive patients from four centers with SET of the upper and middle GI tract were included and received endoscopic or transcutaneous CEUS. The results were compared with EUS-guided tissue acquisition, forceps biopsy, or surgical resection. Results: Forty-two out of 62 (68%) patients had SET of the stomach, 17/62 (27%) of the small intestine, 2/62 (3%) of the esophagus, and 1/62 (2%) extraintestinal. Eighty-one percent underwent surgery. Leiomyoma was found in 5/62 (8%) and GIST in 57/62 patients (92%). Thirty-nine out of 57 (68%) patients had GIST lesions in the stomach, 17/57 (30%) had GIST of the small intestine, and 1/57 (2%) patients had extraintestinal GISTs. GIST size was 62.6 ± 42.1 (16–200) mm. Hyperenhancement had a sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 98%, 100%, 100%, 93%, and 98% for the diagnosis of GIST. Fifty out of 57 patients with GIST (88%) showed avascular areas in the center of the lesions. Conclusion: CE-EUS and CEUS show hyperenhancement and avascular areas in a high percentage of GIST but not in leiomyoma. Thus, GIST and leiomyoma can be discriminated accurately. PMID:28218202

  8. Endoscopic ultrasound elastography for evaluation of lymph nodes and pancreatic masses: a multicenter study.

    PubMed

    Giovannini, Marc; Thomas, Botelberge; Erwan, Bories; Christian, Pesenti; Fabrice, Caillol; Benjamin, Esterni; Geneviève, Monges; Paolo, Arcidiacono; Pierre, Deprez; Robert, Yeung; Walter, Schimdt; Hanz, Schrader; Carl, Szymanski; Christoph, Dietrich; Pierre, Eisendrath; Jean-Luc, Van Laethem; Jacques, Devière; Peter, Vilmann; Andrian, Saftoiu

    2009-04-07

    To evaluate the ability of endoscopic ultrasound (EUS) elastography to distinguish benign from malignant pancreatic masses and lymph nodes. A multicenter study was conducted and included 222 patients who underwent EUS examination with assessment of a pancreatic mass (n = 121) or lymph node (n = 101). The classification as benign or malignant, based on the real time elastography pattern, was compared with the classification based on the B-mode EUS images and with the final diagnosis obtained by EUS-guided fine needle aspiration (EUS-FNA) and/or by surgical pathology. An interobserver study was performed. The sensitivity and specificity of EUS elastography to differentiate benign from malignant pancreatic lesions are 92.3% and 80.0%, respectively, compared to 92.3% and 68.9%, respectively, for the conventional B-mode images. The sensitivity and specificity of EUS elastography to differentiate benign from malignant lymph nodes was 91.8% and 82.5%, respectively, compared to 78.6% and 50.0%, respectively, for the B-mode images. The kappa coefficient was 0.785 for the pancreatic masses and 0.657 for the lymph nodes. EUS elastography is superior compared to conventional B-mode imaging and appears to be able to distinguish benign from malignant pancreatic masses and lymph nodes with a high sensitivity, specificity and accuracy. It might be reserved as a second line examination to help characterise pancreatic masses after negative EUS-FNA and might increase the yield of EUS-FNA for lymph nodes.

  9. JSUM ultrasound elastography practice guidelines: pancreas.

    PubMed

    Hirooka, Yoshiki; Kuwahara, Takamichi; Irisawa, Atsushi; Itokawa, Fumihide; Uchida, Hiroki; Sasahira, Naoki; Kawada, Natsuko; Itoh, Yuya; Shiina, Tsuyoshi

    2015-04-01

    Ultrasound elastography is a relatively new diagnostic technique for measuring the elasticity (hardness) of tissue. Eleven years have passed since the debut of elastography. Various elastography devices are currently being marketed by manufacturers under different names. Pancreatic elastography can be used not only with transabdominal ultrasonography but also with endoscopic ultrasonography, but some types of elastography are difficult to perform for the pancreas. These guidelines aim to classify the various types of elastography into two major categories depending on the differences in the physical quantity (strain, shear wave), and to present the evidence for pancreatic elastography and how to use pancreatic elastography in the present day. But the number of reports on ultrasound elastography for the pancreas is still small, and there are no reports on some elastography devices for the pancreas. Therefore, these guidelines do not recommend methods of imaging and analysis by elastography device.

  10. Endoscopic ultrasound elastography for differentiating between pancreatic adenocarcinoma and inflammatory masses: A meta-analysis

    PubMed Central

    Li, Xiang; Xu, Wei; Shi, Jian; Lin, Yong; Zeng, Xin

    2013-01-01

    AIM: To evaluate the accuracy of endoscopic ultrasound (EUS) elastography for differentiating between pancreatic ductal adenocarcinoma (PDAC) and pancreatic inflammatory masses (PIM). METHODS: Electronic databases (updated to December 2012) and manual bibliographical searches were carried out. A meta-analysis of all diagnostic clinical trials evaluating the accuracy of EUS elastography in differentiating PDAC from PIM was conducted. Heterogeneity was assessed among the studies. The meta-analysis was performed to evaluate the accuracy of EUS elastography in differentiating PDAC from PIM in homogeneous studies. RESULTS: Ten studies involving 781 patients were included in the analysis. Significant heterogeneity in sensitivity was observed among the studies (Cochran Q test = 24.16, df = 9, P = 0.0041, I2 = 62.8%), while heterogeneity in specificity was not observed (Cochran Q test = 5.93, df = 9, P = 0.7473, I2 = 0.0%). The area under the curve under the Sports Rights Owners Coalition was 0.8227. Evaluation of heterogeneity suggested that the different diagnostic standards used in the included studies were the source of heterogeneity. In studies using the color pattern as the diagnostic standard, the pooled sensitivity, specificity, positive likelihood ratio (LR), negative LR and diagnostic OR were 0.99 (0.97-1.00), 0.76 (0.67-0.83), 3.36 (2.39-4.72), 0.03 (0.01-0.07) and 129.96 (47.02-359.16), respectively. In studies using the hue histogram as the diagnostic standard, the pooled sensitivity, specificity, positive LR, negative LR and diagnostic OR were 0.92 (0.89-0.95), 0.68 (0.57-0.78), 2.84 (2.05-3.93), 0.12 (0.08-0.19) and 24.69 (12.81-47.59), respectively. CONCLUSION: EUS elastography is a valuable method for the differential diagnosis between PDAC and PIM. And a preferable diagnostic standard should be explored and improvements in specificity are required. PMID:24115828

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

    PubMed

    Săftoiu, Adrian; Vilmann, Peter; Gorunescu, Florin; Janssen, Jan; Hocke, Michael; Larsen, Michael; Iglesias-Garcia, Julio; Arcidiacono, Paolo; Will, Uwe; Giovannini, Marc; Dietrich, Cristoph F; Havre, Roald; Gheorghe, Cristian; McKay, Colin; Gheonea, Dan Ionuţ; Ciurea, Tudorel

    2012-01-01

    By using strain assessment, real-time endoscopic ultrasound (EUS) elastography provides additional information about a lesion's characteristics in the pancreas. We assessed the accuracy of real-time EUS elastography in focal pancreatic lesions using computer-aided diagnosis by artificial neural network analysis. We performed a prospective, blinded, multicentric study at of 258 patients (774 recordings from EUS elastography) who were diagnosed with chronic pancreatitis (n = 47) or pancreatic adenocarcinoma (n = 211) from 13 tertiary academic medical centers in Europe (the European EUS Elastography Multicentric Study Group). We used postprocessing software analysis to compute individual frames of elastography movies recorded by retrieving hue histogram data from a dynamic sequence of EUS elastography into a numeric matrix. The data then were analyzed in an extended neural network analysis, to automatically differentiate benign from malignant patterns. The neural computing approach had 91.14% training accuracy (95% confidence interval [CI], 89.87%-92.42%) and 84.27% testing accuracy (95% CI, 83.09%-85.44%). These results were obtained using the 10-fold cross-validation technique. The statistical analysis of the classification process showed a sensitivity of 87.59%, a specificity of 82.94%, a positive predictive value of 96.25%, and a negative predictive value of 57.22%. Moreover, the corresponding area under the receiver operating characteristic curve was 0.94 (95% CI, 0.91%-0.97%), which was significantly higher than the values obtained by simple mean hue histogram analysis, for which the area under the receiver operating characteristic was 0.85. Use of the artificial intelligence methodology via artificial neural networks supports the medical decision process, providing fast and accurate diagnoses. Copyright © 2012 AGA Institute. Published by Elsevier Inc. All rights reserved.

  12. Contrast enhancement and elastography in endoscopic ultrasound: an update of clinical applications in pancreatic diseases.

    PubMed

    Serrani, Marta; Lisotti, Andrea; Caletti, Giancarlo; Fusaroli, Pietro

    2016-08-01

    It is well established that endoscopic ultrasound (EUS) is fundamental in the characterization of many diseases concerning different organs, i.e. pancreaticobiliary diseases, gastrointestinal pathologic conditions, and lymph nodes of unknown origin. It is also well known that many factors can hamper the accuracy of EUS, i.e. biliary stents, chronic pancreatitis, poor operator's expertise. These factors can also lead to suboptimal accuracy when cytological confirmation through EUS-fine needle aspiration (EUS-FNA) is indicated. In recent years, new technological tools have rapidly increased their clinical impact improving the diagnostic power of EUS and EUS-FNA. Among these new tools, the most investigated and useful ones are represented by contrast harmonic-EUS (CH-EUS) and EUS-elastography (EUS-E). The purpose of this paper is to provide, through a review of the literature, an update of the applications of CH-EUS and EUS-E in the routine clinical practice in pancreatic diseases. We discussed the first reports and applications of these techniques in our previous review published in Minerva Medica. The applications of CH-EUS and EUS-E to the study of pancreatic diseases appear feasible and safe. The use of both techniques is very simple and does not require any relevant additional workload for the endoscopic personnel. CH-EUS is now considered an important and accurate tool in the diagnosis of solid pancreatic masses and in the differential diagnosis of pancreatic cystic lesions. CH-EUS targeted FNA is an active field of research. However the available studies show that CH-EUS increases FNA accuracy by a little extent, without statistical significance; moreover, CH-EUS FNA showed a trend toward being more efficient vs. simple EUS FNA (less needle passes and more abundance in cytological material) but this trend did not reach statistical significance. On the other hand, the clinical impact of EUS-E in terms of differential diagnosis of pancreatic masses is still under

  13. Mechanics of ultrasound elastography

    PubMed Central

    Li, Guo-Yang

    2017-01-01

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

  14. Intravascular ultrasound elastography.

    PubMed

    van der Steen, A F; de Korte, C L; Céspedes, E I

    1998-10-01

    Intravascular Ultrasound Blastography. The response of a tissue to mechanical excitation is a function of its mechanical properties. Excitation can be dynamic or quasistatic in nature. The response (e.g. displacement, velocity, compression) can be measured via ultrasound. This is the main principle underlying ultrasound elasticity imaging, sonoelasticity imaging, or ultrasound elastography. It is of great interest to know the local hardness of vessel wall and plaques. Intravascular elastography yields information unavailable or inconclusive if obtained from IVUS alone and thus contributes to more correct diagnosis. Potentially it can be used for therapy guidance. During the last decade several working groups used elastography in intravascular applications with varying success. In this paper we discuss the various approaches by different working groups. Focus will be on the approach of the Rotterdam group. Using a 30 MHz IVUS catheter, RF data are acquired from vessels in vitro at different intraluminal pressures. Local tissue displacement estimation by cross-correlation is followed by computation of the local strain. The resulting image supplies local information on the elastic properties of the vessel and plaque with high spatial resolution. Feasibility and usefulness are shown by means of phantom measurements. Furthermore, initial in vitro results of femoral arteries and correlation with histology are discussed. Phantom data show that the elastograms reveal information not presented by the echogram. In vitro artery data prove that in principle elastography is capable of identifying plaque composition where echography fails.

  15. Endoscopic ultrasound

    MedlinePlus

    ... Pancreatitis References Lee LS. Endoscopic ultrasound. In: McNalley PR, ed. GI/Liver Secrets Plus . 5th ed. Philadelphia, ... member of Hi-Ethics and subscribes to the principles of the Health on the Net Foundation (www. ...

  16. Introduction to ultrasound elastography

    PubMed Central

    Dobruch-Sobczak, Katarzyna

    2016-01-01

    For centuries tissue palpation has been an important diagnostic tool. During palpation, tumors are felt as tissues harder than the surrounding tissues. The significance of palpation is related to the relationship between mechanical properties of different tissue lesions. The assessment of tissue stiffness through palpation is based on the fact that mechanical properties of tissues are changing as a result of various diseases. A higher tissue stiffness translates into a higher elasticity modulus. In the 90's, ultrasonography was extended by the option of examining the stiffness of tissue by estimating the difference in backscattering of ultrasound in compressed and non-compressed tissue. This modality is referred to as the static, compression elastography and is based on tracking the deformation of tissue subjected to the slowly varying compression through the recording of the backscattered echoes. The displacement is estimated using the methods of cross-correlation between consecutive ultrasonic lines of examined tissue, so calculating the degree of similarity of ultrasonic echoes acquired from tissue before and after the compression was applied. The next step in the development of ultrasound palpation was to apply the local remote tissue compression by using the acoustic radiation force generated through the special beam forming of the ultrasonic beam probing the tissue. The acoustic radiation force causes a slight deformation the tissue thereby forming a shear wave propagating in the tissue at different speeds dependent on the stiffness of the tissue. Shear wave elastography, carries great hopes in the field of quantitative imaging of tissue lesions. This article describes the physical basis of both elastographic methods: compression elastography and shear wave elastography. PMID:27446596

  17. Ultrasound elastography for musculoskeletal applications

    PubMed Central

    Drakonaki, E E; Allen, G M; Wilson, D J

    2012-01-01

    Ultrasound elastography (EUS) is a method to assess the mechanical properties of tissue, by applying stress and detecting tissue displacement using ultrasound. There are several EUS techniques used in clinical practice; strain (compression) EUS is the most common technique that allows real-time visualisation of the elastographic map on the screen. There is increasing evidence that EUS can be used to measure the mechanical properties of musculoskeletal tissue in clinical practice, with the future potential for early diagnosis to both guide and monitor therapy. This review describes the various EUS techniques available for clinical use, presents the published evidence on musculoskeletal applications of EUS and discusses the technical issues, limitations and future perspectives of this method in the assessment of the musculoskeletal system. PMID:23091287

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

    PubMed

    Dewall, Ryan J

    2013-01-01

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

  19. Endoscopic ultrasound hemostasis techniques.

    PubMed

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

    2014-04-01

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

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

    PubMed Central

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

    2016-01-01

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

  1. Ultrasound elastography in tendon pathology: state of the art.

    PubMed

    Domenichini, Romain; Pialat, Jean-Baptiste; Podda, Andrea; Aubry, Sébastien

    2017-08-01

    Elastography assesses the biomechanical and structural properties of tissues by measuring their stiffness. Despite promising results, elastography has not yet earned its place in the daily practice of musculoskeletal radiologists. The purpose of this article is to present and examine the data available to date on ultrasound elastography of the tendons through a review of the literature to provide musculoskeletal radiologists with an overview that may help them better understand and use elastography routinely. The most common techniques in ultrasound elastography are described. Then, the aspects of the physiologic and pathologic tendon are presented and discussed. One must make this technique one's own to better apprehend its contribution to the musculoskeletal imaging field, while bearing in mind that further research will be required before admitting elastography as a reliable and validated tool able to optimize our daily clinical practice.

  2. Therapeutic endoscopic ultrasound

    PubMed Central

    Venkatachalapathy, Suresh; Nayar, Manu K

    2017-01-01

    Endoscopic ultrasound (EUS) is now firmly established as one of the essential tools for diagnosis in most gastrointestinal MDTs across the UK. However, the ability to provide therapy with EUS has resulted in a significant impact on the management of the patients. These include drainage of peripancreatic collections, EUS-guided endoscopic retrograde cholangiopancreatogram, EUS-guided coeliac plexus blocks, etc. The rapid development of this area in endoscopy is a combination of newer tools and increasing expertise by endosonographers to push the boundaries of intervention with EUS. However, the indications are limited and we are at the start of the learning curve for these high-risk procedures. These therapies should, therefore, be confined to centres with a robust multidisciplinary team, including interventional endoscopists, radiologists and surgeons. PMID:28261439

  3. Endoscopic ultrasound in mediastinal tuberculosis

    PubMed Central

    Sharma, Malay; Ecka, Ruth Shifa; Somasundaram, Aravindh; Shoukat, Abid; Kirnake, Vijendra

    2016-01-01

    Background: Tubercular lymphadenitis is the commonest extra pulmonary manifestation in cervical and mediastinal locations. Normal characteristics of lymph nodes (LN) have been described on ultrasonography as well as by Endoscopic Ultrasound. Many ultrasonic features have been described for evaluation of mediastinal lymph nodes. The inter and intraobserver agreement of the endosonographic features have not been uniformly established. Methods and Results: A total of 266 patients underwent endoscopic ultrasound guided fine needle aspiration and 134 cases were diagnosed as mediastinal tuberculosis. The endoscopic ultrasound location and features of these lymph nodes are described. Conclusion: Our series demonstrates the utility of endoscopic ultrasound guided fine needle aspiration as the investigation of choice for diagnosis of mediastinal tuberculosis and also describes various endoscopic ultrasound features of such nodes. PMID:27051097

  4. Initial experience with real-time elastography using an ultrasound bronchoscope for the evaluation of mediastinal lymph nodes.

    PubMed

    Andreo García, Felipe; Centeno Clemente, Carmen Ángela; Sanz Santos, José; Barturen Barroso, Ángel; Hernández Gallego, Alba; Ruiz Manzano, Juan

    2015-02-01

    Real-time elastography performed during endoscopic ultrasonography is a relatively new method for characterizing tissue stiffness, and has been used successfully as a predictor of malignancy in mediastinal lymph nodes. This case report describes our practical experience with this technique using an ultrasound bronchoscope to examine mediastinal lymph nodes. We present a case of sectorial endobronchial ultrasound and the first published case of endoscopic ultrasound elastography using ultrasound bronchoscope in two patients with non-small cell lung carcinoma. Qualitative tissue color pattern was obtained in both cases and correlated with pathological evaluation. The initial feasibility results are promising and suggest that ultrasound bronchoscopy techniques, such as guided nodal staging, merit additional studies. It may be important to categorize the risk of malignancy to facilitate sampling decisions.

  5. Elastography: A New Ultrasound and MRI Procedure

    SciTech Connect

    Pavan, Theo Z.; Vieira, Silvio L.; Carneiro, Antonio A. O.

    2008-08-11

    Elastography is an imaging technique whereby local tissue strains are estimated from small displacements of internal tissue structure. These displacements are generated from a weak, quasi-static or dynamic stress field. Displacement evaluation through ultrasound is based on time delay estimation between speckle patterns of echo maps acquired for different levels of tissue deformation. A classical model of deformation is applying a quasi-static compression on a sample during echoes acquisition. The elastogram map corresponds to the spatial derivation of the displacement map. By magnetic resonance, the displacement is evaluated from a map of phase acquired using a sequence gradient echo synchronized with a mechanical end sinusoidal excitation. The map of shear elastic modulus is obtained from the phase map.

  6. Elastography: A New Ultrasound and MRI Procedure

    NASA Astrophysics Data System (ADS)

    Pavan, Theo Z.; Vieira, Sílvio L.; Carneiro, Antônio. A. O.

    2008-08-01

    Elastography is an imaging technique whereby local tissue strains are estimated from small displacements of internal tissue structure. These displacements are generated from a weak, quasi-static or dynamic stress field. Displacement evaluation through ultrasound is based on time delay estimation between speckle patterns of echo maps acquired for different levels of tissue deformation. A classical model of deformation is applying a quasi-static compression on a sample during echoes acquisition. The elastogram map corresponds to the spatial derivation of the displacement map. By magnetic resonance, the displacement is evaluated from a map of phase acquired using a sequence gradient echo synchronized with a mechanical end sinusoidal excitation. The map of shear elastic modulus is obtained from the phase map.

  7. [Radiology Update Ultrasound Elastography – Quintessence for the Primary Care Physician].

    PubMed

    Franckenberg, Sabine; Gubler, Christoph; Frauenfelder, Thomas; Rominger, Marga

    2016-02-03

    Ultrasound elastography visualizes and measures elasticity of tissue. Depending on the methods there are four types of elastography: strain elastography (SE), transient elastography (TE), acoustic radiation force impulse imaging (ARFI) and shear wave elastography (SWE). Due to the fact that pathological changes in the tissue in most of the cases mean a lower elasticity, ultrasound elastography is able to diagnose diseases such as liver fibrosis, liver cirrhosis, to help in the diagnosis of suspicious lesions in mamma, prostate and thyroid gland. So far, ultrasound elastography is not yet able to replace other standardized diagnostic tools but can add valuable diagnostic information.

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

    PubMed

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

    2015-10-01

    Ultrasound (US) elastography can provide information about the hardness of calcification and might help decide treatment strategy. The purpose of this study was to evaluate the hardness of the calcific area within rotator cuffs by US elastography as an aid for the selection of aspiration or fine-needle repeated puncture for the treatment of rotator cuff calcific tendinosis. This prospective study included 39 patients (32 males, 7 females; mean age, 52.9 years) who received US elastography and gray-scale ultrasonography before US-guided treatment for rotator cuff calcific tendinosis. The morphology of the calcifications was classified as arc, fragmented, nodular, and cystic types. US elastography using virtual touch imaging (acoustic radiation force impulse) technique was performed to examine the calcified region to obtain an elastogram that was graded dark, intermediate, or bright. The hardness of the calcifications were recorded, and graded as hard, sand-like, or fluid-like tactile patterns during the US-guided treatment, and the tactile patterns were compared with the results of US elastography and gray-scale ultrasonography. Though the morphologies of the calcifications were significantly related to the tactile pattern of the needle punctures (p < 0.001), gray-scale US could not accurately demonstrate the hardness of the calcifications. With the aid of elastography, the fluid-like tactile pattern could be predicted well as a nondark pattern by elastography (p < 0.001). Ultrasound elastography is a useful modality for evaluation of rotator cuff calcific tendinosis, and as an aid to guide management. If elastography shows the calcified area as a non-dark pattern, then fine-needle aspiration should be performed. Copyright © 2015. Published by Elsevier Taiwan.

  9. Ultrasound elastography of the prostate: state of the art.

    PubMed

    Correas, J-M; Tissier, A-M; Khairoune, A; Khoury, G; Eiss, D; Hélénon, O

    2013-05-01

    Prostate cancer is the cancer exhibiting the highest incidence rate and it appears as the second cause of cancer death in men, after lung cancer. Prostate cancer is difficult to detect, and the treatment efficacy remains limited despite the increase use of biological tests (prostate-specific antigen [PSA] dosage), the development of new imaging modalities, and the use of invasive procedures such as biopsy. Ultrasound elastography is a novel imaging technique capable of mapping tissue stiffness of the prostate. It is known that prostatic cancer tissue is often harder than healthy tissue (information used by digital rectal examination [DRE]). Two elastography techniques have been developed based on different principles: first, quasi-static (or strain) technique, and second, shear wave technique. The tissue stiffness information provided by US elastography should improve the detection of prostate cancer and provide guidance for biopsy. Prostate elastography provides high sensitivity for detecting prostate cancer and shows high negative predictive values, ensuring that few cancers will be missed. US elastography should become an additional method of imaging the prostate, complementing the conventional transrectal ultrasound and MRI. This technique requires significant training (especially for quasi-static elastography) to become familiar with acquisition process, acquisition technique, characteristics and limitations, and to achieve correct diagnoses. Copyright © 2013 Éditions françaises de radiologie. Published by Elsevier Masson SAS. All rights reserved.

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

    PubMed

    Karimi, Hirad; Fenster, Aaron; Samani, Abbas

    2013-04-07

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

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

    NASA Astrophysics Data System (ADS)

    Karimi, Hirad; Fenster, Aaron; Samani, Abbas

    2013-04-01

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

  12. Ultrasound Elastography: Review of Techniques and Clinical Applications

    PubMed Central

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

    2017-01-01

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

  13. Dynamic programming on a tree for ultrasound elastography

    NASA Astrophysics Data System (ADS)

    Shams, Roozbeh; Boily, Mathieu; Martineau, Paul A.; Rivaz, Hassan

    2016-04-01

    Ultrasound Elastography is an emerging imaging technique that allows estimation of the mechanical characteristics of tissue. Two issues that need to be addressed before widespread use of elastography in clinical environments are real time constraints and deteriorating effects of signal decorrelation between pre- and post-compression images. Previous work has used Dynamic Programming (DP) to estimate tissue deformation. However, in case of large signal decorrelation, DP can fail. In this paper we, have proposed a novel solution to this problem by solving DP on a tree instead of a single Radio-Frequency line. Formulation of DP on a tree allows exploiting significantly more information, and as such, is more robust and accurate. Our results on phantom and in-vivo human data show that DP on tree significantly outperforms traditional DP in ultrasound elastography.

  14. Contrast harmonic endoscopic ultrasound: Instrumentation, echoprocessors, and echoendoscopes

    PubMed Central

    Iglesias-Garcia, Julio; Lariño-Noia, Jose; Domínguez-Muñoz, J. Enrique

    2017-01-01

    Endoscopic ultrasound (EUS) has become as one the best diagnostic and therapeutic methods for the management of several intraintestinal and extraintestinal diseases, among them to highlight pancreaticobiliary indications, mediastinal evaluation, and the analysis of gastrointestinal lesions. Over the years, there has been an enormous evolution in the systems available to perform EUS. Newer processors and echoendoscopes are available nowadays, with the ability to perform new imaging analysis, such as elastography and contrast enhancement. In the present article, we will review which systems are available nowadays, focusing also in the technical advances associated. PMID:28218199

  15. Applications of endoscopic ultrasound in pancreatic cancer

    PubMed Central

    Luz, Leticia Perondi; Al-Haddad, Mohammad Ali; Sey, Michael Sai Lai; DeWitt, John M

    2014-01-01

    Since the introduction of endoscopic ultrasound guided fine-needle aspiration (EUS-FNA), EUS has assumed a growing role in the diagnosis and management of pancreatic ductal adenocarcinoma (PDAC). The objective of this review is to discuss the various applications of EUS and EUS-FNA in PDAC. Initially, its use for detection, diagnosis and staging will be described. EUS and EUS-FNA are highly accurate modalities for detection and diagnosis of PDAC, this high accuracy, however, is decreased in specific situations particularly in the presence of chronic pancreatitis. Novel techniques such as contrast-enhanced EUS, elastography and analysis of DNA markers such as k-ras mutation analysis in FNA samples are in progress and might improve the accuracy of EUS in the detection of PDAC in this setting and will be addressed. EUS and EUS-FNA have recently evolved from a diagnostic to a therapeutic technique in the management of PDAC. Significant developments in therapeutic EUS have occurred including advances in celiac plexus interventions with direct injection of ganglia and improved pain control, EUS-guided fiducial and brachytherapy seed placement, fine-needle injection of intra-tumoral agents and advances in EUS-guided biliary drainage. The future role of EUS and EUS in management of PDAC is still emerging. PMID:24976719

  16. Applications of endoscopic ultrasound in pancreatic cancer.

    PubMed

    Luz, Leticia Perondi; Al-Haddad, Mohammad Ali; Sey, Michael Sai Lai; DeWitt, John M

    2014-06-28

    Since the introduction of endoscopic ultrasound guided fine-needle aspiration (EUS-FNA), EUS has assumed a growing role in the diagnosis and management of pancreatic ductal adenocarcinoma (PDAC). The objective of this review is to discuss the various applications of EUS and EUS-FNA in PDAC. Initially, its use for detection, diagnosis and staging will be described. EUS and EUS-FNA are highly accurate modalities for detection and diagnosis of PDAC, this high accuracy, however, is decreased in specific situations particularly in the presence of chronic pancreatitis. Novel techniques such as contrast-enhanced EUS, elastography and analysis of DNA markers such as k-ras mutation analysis in FNA samples are in progress and might improve the accuracy of EUS in the detection of PDAC in this setting and will be addressed. EUS and EUS-FNA have recently evolved from a diagnostic to a therapeutic technique in the management of PDAC. Significant developments in therapeutic EUS have occurred including advances in celiac plexus interventions with direct injection of ganglia and improved pain control, EUS-guided fiducial and brachytherapy seed placement, fine-needle injection of intra-tumoral agents and advances in EUS-guided biliary drainage. The future role of EUS and EUS in management of PDAC is still emerging.

  17. Endoscopic ultrasound: Elastographic lymph node evaluation

    PubMed Central

    Dietrich, Christoph F.; Jenssen, Christian; Arcidiacono, Paolo G.; Cui, Xin-Wu; Giovannini, Marc; Hocke, Michael; Iglesias-Garcia, Julio; Saftoiu, Adrian; Sun, Siyu; Chiorean, Liliana

    2015-01-01

    Different imaging techniques can bring different information which will contribute to the final diagnosis and further management of the patients. Even from the time of Hippocrates, palpation has been used in order to detect and characterize a body mass. The so-called virtual palpation has now become a reality due to elastography, which is a recently developed technique. Elastography has already been proving its added value as a complementary imaging method, helpful to better characterize and differentiate between benign and malignant masses. The current applications of elastography in lymph nodes (LNs) assessment by endoscopic ultrasonography will be further discussed in this paper, with a review of the literature and future perspectives. PMID:26374575

  18. Real-time quasi-static ultrasound elastography

    PubMed Central

    Treece, Graham; Lindop, Joel; Chen, Lujie; Housden, James; Prager, Richard; Gee, Andrew

    2011-01-01

    Ultrasound elastography is a technique used for clinical imaging of tissue stiffness with a conventional ultrasound machine. It was first proposed two decades ago, but active research continues in this area to the present day. Numerous clinical applications have been investigated, mostly related to cancer imaging, and though these have yet to prove conclusive, the technique has seen increasing commercial and clinical interest. This paper presents a review of the most widely adopted, non-quantitative, techniques focusing on technical innovations rather than clinical applications. The review is not intended to be exhaustive, concentrating instead on placing the various techniques in context according to the authors' perspective of the field. PMID:22866230

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

    PubMed Central

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

    2015-01-01

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

  20. Therapeutic aspects of endoscopic ultrasound

    NASA Astrophysics Data System (ADS)

    Woodward, Timothy A.

    1999-06-01

    Endoscopic ultrasound (EUS) is a technology that had been used primarily as a passive imaging modality. Recent advances have enabled us to move beyond the use of EUS solely as a staging tool to an interventional device. Current studies suggest that interventional applications of EUS will allow for minimally invasive assessment and therapies in a cost-effective manner. Endoscopic ultrasound with fine needle aspiration (EUS-FNA) has been demonstrated to be a technically feasible, relatively safe method of obtaining cytologic specimens. The clinical utility of EUS- FNA appears to be greatest in the diagnosis and staging of pancreatic cancer and in the nodal staging of gastrointestinal and pulmonary malignancies. In addition, EUS-FNA has demonstrated utility in the sampling pleural and ascitic fluid not generally appreciated or assessable to standard interventions. Interventional applications of EUS include EUS-guided pseudocyst drainage, EUS-guided injection of botulinum toxin in the treatment of achalasia, and EUS- guided celiac plexus neurolysis in the treatment of pancreatic cancer pain. Finally, EUS-guided fine-needle installation is being evaluated, in conjunction with recent bimolecular treatment modalities, as a delivery system in the treatment of certain gastrointestinal tumors.

  1. Diagnostic potential of endoscopic ultrasonography-elastography for gastric submucosal tumors: A pilot study.

    PubMed

    Tsuji, Yuichiro; Kusano, Chika; Gotoda, Takuji; Itokawa, Fumihide; Fukuzawa, Masakatsu; Sofuni, Atsushi; Matsubayashi, Jun; Nagao, Toshitaka; Itoi, Takao; Moriyasu, Fuminori

    2016-03-01

    Qualitative diagnosis for gastric submucosal tumors (SMT) is not easy. Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) in combination with EUS-elastography (EUS-EG) is reported useful for qualitatively diagnosing pancreatic tissues. We prospectively studied whether EUS-EG could be useful in qualitative diagnosis of gastric SMT. We prospectively registered 25 consecutive patients with gastric SMT diagnosed by esophagogastroduodenoscopy and carried out qualitative evaluations using EUS-EG (May 2013 to March 2015) followed by histopathological diagnosis using EUS-FNA or endoscopic mucosal cutting biopsy. Elastic scores of gastric SMT were compared to the cytological diagnosis. Of 25 patients, 22 had a confirmed cytological diagnosis. Regarding the Giovannini elastic score, of three patients with aberrant pancreas, one was score 1 and two were score 2; of eight patients with leiomyoma, seven were score 2 and one was score 3. Both of two patients with schwannoma were score 4. Of nine patients with gastrointestinal stromal tumor, six were score 4 and three were score 5. Gastrointestinal stromal tumor (GIST) is harder than other types of gastric SMT, and our study's findings suggested the usefulness of EUS-EG, which can also assess tumor hardness of gastric SMT. EUS-EG might be helpful for the differential diagnosis of gastric SMT, especially to differentiate GIST from other SMT. © 2015 Japan Gastroenterological Endoscopy Society.

  2. Propofol use in endoscopic retrograde cholangiopancreatography and endoscopic ultrasound

    PubMed Central

    Cheriyan, Danny G; Byrne, Michael F

    2014-01-01

    Compared to standard endoscopy, endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic ultrasound (EUS) are often lengthier and more complex, thus requiring higher doses of sedatives for patient comfort and compliance. The aim of this review is to provide the reader with information regarding the use, safety profile, and merits of propofol for sedation in advanced endoscopic procedures like ERCP and EUS, based on the current literature. PMID:24833847

  3. Endoscopic ultrasound guided interventional procedures.

    PubMed

    Sharma, Vishal; Rana, Surinder S; Bhasin, Deepak K

    2015-06-10

    Endoscopic ultrasound (EUS) has emerged as an important diagnostic and therapeutic modality in the field of gastrointestinal endoscopy. EUS provides access to many organs and lesions which are in proximity to the gastrointestinal tract and thus giving an opportunity to target them for therapeutic and diagnostic purposes. This modality also provides a real time opportunity to target the required area while avoiding adjacent vascular and other structures. Therapeutic EUS has found role in management of pancreatic fluid collections, biliary and pancreatic duct drainage in cases of failed endoscopic retrograde cholangiopancreatography, drainage of gallbladder, celiac plexus neurolysis/blockage, drainage of mediastinal and intra-abdominal abscesses and collections and in targeted cancer chemotherapy and radiotherapy. Infact, therapeutic EUS has emerged as the therapy of choice for management of pancreatic pseudocysts and recent innovations like fully covered removable metallic stents have improved results in patients with organised necrosis. Similarly, EUS guided drainage of biliary tract and pancreatic duct helps drainage of these systems in patients with failed cannulation, inaccessible papilla as with duodenal/gastric obstruction or surgically altered anatomy. EUS guided gall bladder drainage is a useful emergent procedure in patients with acute cholecystitis who are not fit for surgery. EUS guided celiac plexus neurolysis and blockage is more effective and less morbid vis-à-vis the percutaneous technique. The field of interventional EUS is rapidly advancing and many more interventions are being continuously added. This review focuses on the current status of evidence vis-à-vis the established indications of therapeutic EUS.

  4. Update on ultrasound elastography: miscellanea. Prostate, testicle, musculo-skeletal.

    PubMed

    Correas, J M; Drakonakis, E; Isidori, A M; Hélénon, O; Pozza, C; Cantisani, V; Di Leo, N; Maghella, F; Rubini, A; Drudi, F M; D'ambrosio, F

    2013-11-01

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

  5. Current status of tissue harmonic imaging in endoscopic ultrasonography (EUS) and EUS-elastography in pancreatobiliary diseases.

    PubMed

    Ohno, Eizaburo; Kawashima, Hiroki; Hashimoto, Senju; Goto, Hidemi; Hirooka, Yoshiki

    2015-04-01

    Endoscopic ultrasonography (EUS) has high spatial and contrast resolution, and is thought to be one of the most reliable and efficient diagnostic modalities for pancreatobiliary diseases. Recent progress in EUS, especially in the development of the electronic scanning method, has enabled the application of several utilities and software of a high-end transabdominal ultrasound apparatus as an image-enhanced EUS. Tissue harmonic imaging (THI) is a novel US acquisition method that provides better US images by using second harmonic signals. The potential advantages of THI are improved lateral resolution, reduced side lobe artifact and an increased signal-to-noise ratio. EUS-elastography is another novel technique that provides information about the distributed pattern of tissue hardness. Clinical benefits of EUS-elastography for the differential diagnosis of pancreatic tumors and the evaluation of pancreatic fibrosis have been reported. It is necessary to develop a unified and objective method of imaging and analysis to increase the use of EUS-elastography in the future. © 2015 The Authors. Digestive Endoscopy © 2015 Japan Gastroenterological Endoscopy Society.

  6. A new shear wave imaging system for ultrasound elastography.

    PubMed

    Qiu, Weibao; Wang, Congzhi; Xiao, Yang; Qian, Ming; Zheng, Hairong

    2015-08-01

    Ultrasound elastography is able to provide a non-invasive measurement of tissue elasticity properties. Shear wave imaging (SWI) technique is a quantitative method for tissue stiffness assessment. However, traditional SWI implementations cannot acquire 2D quantitative images of tissue elasticity distribution. In this study, a new shear wave imaging system is proposed and evaluated. Detailed delineation of hardware and image processing algorithms are presented. Programmable devices are selected to support flexible control of the system and the image processing algorithms. Analytic signal based cross-correlation method and a Radon transform based shear wave speed determination method are proposed with parallel computation ability. Tissue mimicking phantom imaging, and in vitro imaging measurements are conducted to demonstrate the performance of the proposed system. The system has the ability to provide a new choice for quantitative mapping of the tissue elasticity, and has good potential to be implemented into commercial ultrasound scanner.

  7. Endoscopic ultrasound in the diagnosis and treatment of pancreatic disease

    PubMed Central

    Teshima, Christopher W; Sandha, Gurpal S

    2014-01-01

    Endoscopic ultrasound (EUS) is an important part of modern gastrointestinal endoscopy and now has an integral role in the diagnostic evaluation of pancreatic diseases. Furthermore, as EUS technology has advanced, it has increasingly become a therapeutic procedure, and the prospect of multiple applications of interventional EUS for the pancreas is truly on the near horizon. However, this review focuses on the established diagnostic and therapeutic roles of EUS that are used in current clinical practice. In particular, the diagnostic evaluation of acute pancreatitis, chronic pancreatitis, cystic pancreatic lesions and solid masses of the pancreas are discussed. The newer enhanced imaging modalities of elastography and contrast enhancement are evaluated in this context. The main therapeutic aspects of pancreatic EUS are then considered, namely celiac plexus block and celiac plexus neurolysis for pain control in chronic pancreatitis and pancreas cancer, and EUS-guided drainage of pancreatic fluid collections. PMID:25110426

  8. Role of contrast-enhanced endoscopic ultrasound in lymph nodes

    PubMed Central

    Hocke, Michael; Ignee, Andre; Dietrich, Christoph

    2017-01-01

    Diagnosing unclear lymph node (LN) enlargements in the mediastinum and abdomen is the most important indication of endoscopic ultrasound (EUS)-fine needle aspiration (FNA) after the diagnosis and treatment of pancreatic diseases. Investigating LNs in these areas can happen in different clinical settings. Mostly, it is the first modality in general LN diseases without any peripheral LN enlargements. On the other hand, it can be the question of LN involvement in a known or suspected primary tumor. Due to EUS-FNA cytology, those questions can be answered highly, accurately. However, a primary discrimination of LNs might be helpful to increase the diagnostic value of the FNA cytology, especially in cases with multiple LN enlargements and hard to reach enlarged LNs for example by vessel interposition. Because of the unreliability of B-mode criteria, further diagnostic improvements such as elastography and contrast-enhanced EUS are investigated to increase the accuracy of the initial diagnosis. PMID:28218194

  9. Endoscopic ultrasound guided interventional procedures

    PubMed Central

    Sharma, Vishal; Rana, Surinder S; Bhasin, Deepak K

    2015-01-01

    Endoscopic ultrasound (EUS) has emerged as an important diagnostic and therapeutic modality in the field of gastrointestinal endoscopy. EUS provides access to many organs and lesions which are in proximity to the gastrointestinal tract and thus giving an opportunity to target them for therapeutic and diagnostic purposes. This modality also provides a real time opportunity to target the required area while avoiding adjacent vascular and other structures. Therapeutic EUS has found role in management of pancreatic fluid collections, biliary and pancreatic duct drainage in cases of failed endoscopic retrograde cholangiopancreatography, drainage of gallbladder, celiac plexus neurolysis/blockage, drainage of mediastinal and intra-abdominal abscesses and collections and in targeted cancer chemotherapy and radiotherapy. Infact, therapeutic EUS has emerged as the therapy of choice for management of pancreatic pseudocysts and recent innovations like fully covered removable metallic stents have improved results in patients with organised necrosis. Similarly, EUS guided drainage of biliary tract and pancreatic duct helps drainage of these systems in patients with failed cannulation, inaccessible papilla as with duodenal/gastric obstruction or surgically altered anatomy. EUS guided gall bladder drainage is a useful emergent procedure in patients with acute cholecystitis who are not fit for surgery. EUS guided celiac plexus neurolysis and blockage is more effective and less morbid vis-à-vis the percutaneous technique. The field of interventional EUS is rapidly advancing and many more interventions are being continuously added. This review focuses on the current status of evidence vis-à-vis the established indications of therapeutic EUS. PMID:26078831

  10. Reliability and validity of quantifying absolute muscle hardness using ultrasound elastography.

    PubMed

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

    2012-01-01

    Muscle hardness is a mechanical property that represents transverse muscle stiffness. A quantitative method that uses ultrasound elastography for quantifying absolute human muscle hardness has been previously devised; however, its reliability and validity have not been completely verified. This study aimed to verify the reliability and validity of this quantitative method. The Young's moduli of seven tissue-mimicking materials (in vitro; Young's modulus range, 20-80 kPa; increments of 10 kPa) and the human medial gastrocnemius muscle (in vivo) were quantified using ultrasound elastography. On the basis of the strain/Young's modulus ratio of two reference materials, one hard and one soft (Young's moduli of 7 and 30 kPa, respectively), the Young's moduli of the tissue-mimicking materials and medial gastrocnemius muscle were calculated. The intra- and inter-investigator reliability of the method was confirmed on the basis of acceptably low coefficient of variations (≤6.9%) and substantially high intraclass correlation coefficients (≥0.77) obtained from all measurements. The correlation coefficient between the Young's moduli of the tissue-mimicking materials obtained using a mechanical method and ultrasound elastography was 0.996, which was equivalent to values previously obtained using magnetic resonance elastography. The Young's moduli of the medial gastrocnemius muscle obtained using ultrasound elastography were within the range of values previously obtained using magnetic resonance elastography. The reliability and validity of the quantitative method for measuring absolute muscle hardness using ultrasound elastography were thus verified.

  11. Training in Endoscopy: Endoscopic Ultrasound.

    PubMed

    Cho, Chang Min

    2017-07-01

    Endoscopic ultrasound (EUS) has been recently established as an indispensable modality for the diagnosis and management of pancreatobiliary and gastrointestinal (GI) disorders. EUS proficiency requires both cognitive and technical abilities, including an understanding of the appropriate indications, the performance of appropriate evaluations before and after the procedure, and the management of procedure-related complications. An increasing demand for skills to handle a growing range of interventional EUS procedures and a continual shortage of EUS training programs are two major obstacles for EUS training. Acquiring the skills necessary to comprehend and conduct EUS often requires training beyond the scope of a standard GI fellowship program. In addition to traditional formal EUS training and preceptorships, regular short-term intensive EUS training programs that provide training at various levels may help EUS practitioners improve and maintain EUS-related knowledges and skills. Theoretical knowledge can be acquired from lectures, textbooks, atlases, slides, videotapes, digital video discs, interactive compact discs, and websites. Informal EUS training is generally based on 1- or 2-day intensive seminars, including didactic lectures, skills demonstrated by expert practitioners through live video-streaming of procedures, and hands-on learning using animal or phantom models.

  12. Ultrasound Vascular Elastography as a Tool for Assessing Atherosclerotic Plaques – A Systematic Literature Review

    PubMed Central

    Mahmood, B.; Ewertsen, C.; Carlsen, J.; Nielsen, M. B.

    2016-01-01

    Atherosclerosis is a widespread disease that accounts for nearly 3-quarters of deaths due to cardiovascular disease. Ultrasound elastography might be able to reliably identify characteristics associated with vulnerable plaques. There is a need for the evaluation of elastography and its ability to distinguish between vulnerable and stable plaques. The aim of this paper is to provide an overview of the literature on vascular elastography. A systematic search of the available literature for studies using elastography for assessing atherosclerotic plaques was conducted using the MEDLINE, Embase, Cochrane Library and Web of Science databases. A standardized template was used to extract relevant data following the PRISMA 2009 checklist. 20 articles were included in this paper. The studies were heterogeneous. All studies reported that elastography was a feasible technique and provided additional information compared to B-mode ultrasound alone. Most studies reported higher strain values for vulnerable plaques. Ultrasound elastography has potential as a clinical tool in the assessment of atherosclerotic plaques. Elastography is able to distinguish between different plaque types, but there is considerable methodological variation between studies. There is a need for larger studies in a clinical setting to determine the full potential of elastography. PMID:27896334

  13. Use of Ultrasound Elastography in the Assessment of the Musculoskeletal System

    PubMed Central

    Paluch, Łukasz; Nawrocka-Laskus, Ewa; Wieczorek, Janusz; Mruk, Bartosz; Frel, Małgorzata; Walecki, Jerzy

    2016-01-01

    Summary This article presents possible applications of ultrasound elastography in musculoskeletal imaging based on the available literature, as well as the possibility of extending indications for the use of elastography in the future. Ultrasound elastography (EUS) is a new method that shows structural changes in tissues following application of physical stress. Elastography techniques have been widely used to assess muscles and tendons in vitro since the early parts of the twentieth century. Only recently with the advent of new technology and creation of highly specialized ultrasound devices, has elastography gained widespread use in numerous applications. The authors performed a search of the Medline/PubMed databases for original research and reviewed publications on the application of ultrasound elastography for musculoskeletal imaging. All publications demonstrate possible uses of ultrasound elastography in examinations of the musculoskeletal system. The most widely studied areas include the muscles, tendons and rheumatic diseases. There are also reports on the employment in vessel imaging. The main limitation of elastography as a technique is above all the variability of applied pressure during imaging, which is operator-dependent. It would therefore be reasonable to provide clear guidelines on the technique applied, as well as clear indications for performing the test. It is important to develop methods for creating artifact-free, closed-loop, compression-decompression cycles. The main advantages include cost-effectiveness, short duration of the study, non-invasive nature of the procedure, as well as a potentially broader clinical availability. There are no clear guidelines with regard to indications as well as examination techniques. Ultrasound elastography is a new and still poorly researched method. We conclude, however, that it can be widely used in the examinations of musculoskeletal system. Therefore, it is necessary to conduct large, multi

  14. Pulmonary ultrasound elastography: a feasibility study with phantoms and ex-vivo tissue

    NASA Astrophysics Data System (ADS)

    Nguyen, Man Minh; Xie, Hua; Paluch, Kamila; Stanton, Douglas; Ramachandran, Bharat

    2013-03-01

    Elastography has become widely used for minimally invasive diagnosis in many tumors as seen with breast, liver and prostate. Among different modalities, ultrasound-based elastography stands out due to its advantages including being safe, real-time, and relatively low-cost. While lung cancer is the leading cause of cancer mortality among both men and women, the use of ultrasound elastography for lung cancer diagnosis has hardly been investigated due to the limitations of ultrasound in air. In this work, we investigate the use of static-compression based endobronchial ultrasound elastography by a 3D trans-oesophageal echocardiography (TEE) transducer for lung cancer diagnosis. A water-filled balloon was designed to 1) improve the visualization of endobronchial ultrasound and 2) to induce compression via pumping motion inside the trachea and bronchiole. In a phantom study, we have successfully generated strain images indicating the stiffness difference between the gelatin background and agar inclusion. A similar strain ratio was confirmed with Philips ultrasound strain-based elastography product. For ex-vivo porcine lung study, different tissue ablation methods including chemical injection, Radio Frequency (RF) ablation, and direct heating were implemented to achieve tumor-mimicking tissue. Stiff ablated lung tissues were obtained and detected with our proposed method. These results suggest the feasibility of pulmonary elastography to differentiate stiff tumor tissue from normal tissue.

  15. Global Time-Delay Estimation in Ultrasound Elastography.

    PubMed

    Hashemi, Hoda Sadat; Rivaz, Hassan

    2017-10-01

    A critical step in quasi-static ultrasound elastography is the estimation of time delay between two frames of radio-frequency (RF) data that are obtained while the tissue is undergoing deformation. This paper presents a novel technique for time-delay estimation (TDE) of all samples of RF data simultaneously, thereby exploiting all the information in RF data for TDE. A nonlinear cost function that incorporates similarity of RF data intensity and prior information of displacement continuity is formulated. Optimization of this function involves searching for TDE of all samples of the RF data, rendering the optimization intractable with conventional techniques given that the number of variables can be approximately one million. Therefore, the optimization problem is converted to a sparse linear system of equations, and is solved in real time using a computationally efficient optimization technique. We call our method GLobal Ultrasound Elastography (GLUE), and compare it to dynamic programming analytic minimization (DPAM) and normalized cross correlation (NCC) techniques. Our simulation results show that the contrast-to-noise ratio (CNR) values of the axial strain maps are 4.94 for NCC, 14.62 for DPAM, and 26.31 for GLUE. Our results on experimental data from tissue mimicking phantoms show that the CNR values of the axial strain maps are 1.07 for NCC, 16.01 for DPAM, and 18.21 for GLUE. Finally, our results on in vivo data show that the CNR values of the axial strain maps are 3.56 for DPAM and 13.20 for GLUE.

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

    PubMed

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

    2011-11-01

    Soft tissue displacements during minimally invasive surgical procedures may cause target motion and subsequent misplacement of the surgical tool. A technique is presented to predict target displacements using a combination of ultrasound elastography and finite element (FE) modeling. A cubic gelatin/agar phantom with stiff targets was manufactured to obtain pre- and post-loading ultrasound radio frequency (RF) data from a linear array transducer. The RF data were used to compute displacement and strain images, from which the distribution of elasticity was reconstructed using an inverse FE-based approach. The FE model was subsequently used to predict target displacements upon application of different boundary and loading conditions to the phantom. The influence of geometry was investigated by application of the technique to a breast-shaped phantom. The distribution of elasticity in the phantoms as determined from the strain distribution agreed well with results from mechanical testing. Upon application of different boundary and loading conditions to the cubic phantom, the FE model-predicted target motion were consistent with ultrasound measurements. The FE-based approach could also accurately predict the displacement of the target upon compression and indentation of the breast-shaped phantom. This study provides experimental evidence that organ geometry and boundary conditions surrounding the organ are important factors influencing target motion. In future work, the technique presented in this paper could be used for preoperative planning of minimally invasive surgical interventions.

  17. Ultrasound scoring in combination with ultrasound elastography for differentiating benign and malignant thyroid nodules.

    PubMed

    Shao, Jun; Shen, Ye; Lü, Jieqiong; Wang, Jianming

    2015-08-01

    The aim of this study was to evaluate the value of ultrasound scores obtained by conventional ultrasonography and ultrasound elastography in the differentiation of benign and malignant thyroid nodules in Chinese patients. This study included 297 patients who were referred for surgery for compressive symptoms or suspicion of malignancy. Five hundred and twelve thyroid nodules were examined by ultrasonography. The final diagnosis was based on histological findings. A seven-point ultrasound scoring system based on conventional ultrasonography and a five-point scoring system based on ultrasound elastography were applied independently or in combination. The receiver operating characteristic (ROC) curves were graphed, and the areas under the curves (AUCs) were compared using the χ(2) -test. Solid composition, hypo-echoic appearance, an irregular or blurred margin, an aspect ratio ≥1, intranodular blood flow and presence of microcalcifications were significant predictors of malignant thyroid nodules. The AUC (95% CI) was 0·9067 (0·8817-0·9318) for the ultrasound scores based on conventional ultrasonography and 0·9080 (0·8842-0·9317) for the elasticity scores. The combination of these two scoring systems provided good accuracy with an AUC (95% CI) of 0·9415 (0·9223-0·9606), which was significantly higher than that obtained with the conventional ultrasound scores (χ(2)  = 36·03, P < 0·001) or the elasticity scores (χ(2)  = 12·80, P < 0·001) individually. When we set the cut-point to ≥5, the sensitivity and specificity were 85·22% and 87·38%, respectively. Elastography in combination with conventional ultrasonography is a promising imaging-based approach that can assist in the differential diagnosis of thyroid cancer. © 2014 John Wiley & Sons Ltd.

  18. Correlates of mammographic density in B-mode ultrasound and real time elastography.

    PubMed

    Jud, Sebastian Michael; Häberle, Lothar; Fasching, Peter A; Heusinger, Katharina; Hack, Carolin; Faschingbauer, Florian; Uder, Michael; Wittenberg, Thomas; Wagner, Florian; Meier-Meitinger, Martina; Schulz-Wendtland, Rüdiger; Beckmann, Matthias W; Adamietz, Boris R

    2012-07-01

    The aim of our study involved the assessment of B-mode imaging and elastography with regard to their ability to predict mammographic density (MD) without X-rays. Women, who underwent routine mammography, were prospectively examined with additional B-mode ultrasound and elastography. MD was assessed quantitatively with a computer-assisted method (Madena). The B-mode and elastography images were assessed by histograms with equally sized gray-level intervals. Regression models were built and cross validated to examine the ability to predict MD. The results of this study showed that B-mode imaging and elastography were able to predict MD. B-mode seemed to give a more accurate prediction. R for B-mode image and elastography were 0.67 and 0.44, respectively. Areas in the B-mode images that correlated with mammographic dense areas were either dark gray or of intermediate gray levels. Concerning elastography only the gray levels that represent extremely stiff tissue correlated positively with MD. In conclusion, ultrasound seems to be able to predict MD. Easy and cheap utilization of regular breast ultrasound machines encourages the use of ultrasound in larger case-control studies to validate this method as a breast cancer risk predictor. Furthermore, the application of ultrasound for breast tissue characterization could enable comprehensive research concerning breast cancer risk and breast density in young and pregnant women.

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

    NASA Astrophysics Data System (ADS)

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

    2014-03-01

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

  20. Endoscopic ultrasound for the characterization and staging of rectal cancer. Current state of the method. Technological advances and perspectives.

    PubMed

    Gersak, Mariana M; Badea, Radu; Graur, Florin; Hajja, Nadim Al; Furcea, Luminita; Dudea, Sorin M

    2015-06-01

    Endoscopic ultrasound is the most accurate type of examination for the assessment of rectal tumors. Over the years, the method has advanced from gray-scale examination to intravenous contrast media administration and to different types of elastography. The multimodal approach of tumors (transrectal, transvaginal) is adapted to each case. 3D ultrasound is useful for spatial representation and precise measurement of tumor formations, using CT/MR image reconstruction; color elastography is useful for tumor characterization and staging; endoscopic ultrasound using intravenous contrast agents can help study the amount of contrast agent targeted at the level of the tumor formations and contrast wash-in/wash-out time, based on the curves displayed on the device. The transvaginal approach often allows better visualization of the tumor than the transrectal approach. Performing the procedure with the rectal ampulla distended with contrast agent may be seen as an optimization of the examination methodology. All these aspects are additional methods for gray-scale endoscopic ultrasound, capable of increasing diagnostic accuracy. This paper aims at reviewing the progress of transrectal and transvaginal ultrasound, generically called endoscopic ultrasound, for rectal tumor diagnosis and staging, with emphasis on the current state of the method and its development trends.

  1. Imaging feedback of histotripsy treatments using ultrasound shear wave elastography.

    PubMed

    Wang, Tzu-Yin; Hall, Timothy L; Xu, Zhen; Fowlkes, J Brian; Cain, Charles A

    2012-06-01

    Histotripsy is a cavitation-based ultrasound therapy that mechanically fractionates soft solid tissues into fluid-like homogenates. This paper investigates the feasibility of imaging the tissue elasticity change during the histotripsy process as a tool to provide feedback for the treatments. The treatments were performed on agar tissue phantoms and ex vivo kidneys using 3-cycle ultrasound pulses delivered by a 750-kHz therapeutic array at peak negative/positive pressure of 17/108 MPa and a repetition rate of 50 Hz. Lesions with different degrees of damage were created with increasing numbers of therapy pulses from 0 to 2000 pulses per treatment location. The elasticity of the lesions was measured with ultrasound shear wave elastography, in which a quasi-planar shear wave was induced by acoustic radiation force generated by the therapeutic array, and tracked with ultrasound imaging at 3000 frames per second. Based on the shear wave velocity calculated from the sequentially captured frames, the Young's modulus was reconstructed. Results showed that the lesions were more easily identified on the shear wave velocity images than on B-mode images. As the number of therapy pulses increased from 0 to 2000 pulses/location, the Young's modulus decreased exponentially from 22.1 ± 2.7 to 2.1 ± 1.1 kPa in the tissue phantoms (R2 = 0.99, N = 9 each), and from 33.0 ± 7.1 to 4.0 ± 2.5 kPa in the ex vivo kidneys (R2 = 0.99, N = 8 each). Correspondingly, the tissues transformed from completely intact to completely fractionated as examined via histology. A good correlation existed between the lesions' Young's modulus and the degree of tissue fractionation as examined with the percentage of remaining structurally intact cell nuclei (R2 = 0.91, N = 8 each). These results indicate that lesions produced by histotripsy can be detected with high sensitivity using shear wave elastography. Because the decrease in the tissue elasticity corresponded well with the morphological and

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

    PubMed

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

    2015-02-01

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

  3. Hepatic applications of endoscopic ultrasound: Current status and future directions

    PubMed Central

    Srinivasan, Indu; Tang, Shou-Jiang; Vilmann, Andreas S; Menachery, John; Vilmann, Peter

    2015-01-01

    The diagnosis and staging of various gastrointestinal malignancies have been made possible with the use of endoscopic ultrasound, which is a relatively safe procedure. The field of endoscopic ultrasound is fast expanding due to advancements in therapeutic endoscopic ultrasound. Though various studies have established its role in gastrointestinal malignancies and pancreatic conditions, its potential in the field of hepatic lesions still remains vastly untapped. In this paper the authors attempt to review important and landmark trials, case series and case studies involving hepatic applications of endoscopic ultrasound, thus not only providing an overview of utilization of endoscopic ultrasound in various liver conditions but also speculating its future role. PMID:26640331

  4. Hepatic applications of endoscopic ultrasound: Current status and future directions.

    PubMed

    Srinivasan, Indu; Tang, Shou-Jiang; Vilmann, Andreas S; Menachery, John; Vilmann, Peter

    2015-11-28

    The diagnosis and staging of various gastrointestinal malignancies have been made possible with the use of endoscopic ultrasound, which is a relatively safe procedure. The field of endoscopic ultrasound is fast expanding due to advancements in therapeutic endoscopic ultrasound. Though various studies have established its role in gastrointestinal malignancies and pancreatic conditions, its potential in the field of hepatic lesions still remains vastly untapped. In this paper the authors attempt to review important and landmark trials, case series and case studies involving hepatic applications of endoscopic ultrasound, thus not only providing an overview of utilization of endoscopic ultrasound in various liver conditions but also speculating its future role.

  5. Role of endoscopic ultrasound in the diagnosis of pancreatic cancer

    PubMed Central

    Gonzalo-Marin, Juana; Vila, Juan Jose; Perez-Miranda, Manuel

    2014-01-01

    Endoscopic ultrasonography (EUS) with or without fine needle aspiration has become the main technique for evaluating pancreatobiliary disorders and has proved to have a higher diagnostic yield than positron emission tomography, computed tomography (CT) and transabdominal ultrasound for recognising early pancreatic tumors. As a diagnostic modality for pancreatic cancer, EUS has proved rates higher than 90%, especially for lesions less than 2-3 cm in size in which it reaches a sensitivity rate of 99% vs 55% for CT. Besides, EUS has a very high negative predictive value and thus EUS can reliably exclude pancreatic cancer. The complication rate of EUS is as low as 1.1%-3.0%. New technical developments such as elastography and the use of contrast agents have recently been applied to EUS, improving its diagnostic capability. EUS has been found to be superior to the recent multidetector CT for T staging with less risk of overstaying in comparison to both CT and magnetic resonance imaging, so that patients are not being ruled out of a potentially beneficial resection. The accuracy for N staging with EUS is 64%-82%. In unresectable cancers, EUS also plays a therapeutic role by means of treating oncological pain through celiac plexus block, biliary drainage in obstructive jaundice in patients where endoscopic retrograde cholangiopancreatography is not affordable and aiding radiotherapy and chemotherapy. PMID:25232461

  6. Towards clinical prostate ultrasound elastography using full inversion approach.

    PubMed

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

    2014-03-01

    Various types of cancers including prostate cancer are known to be associated with biological changes that lead to tissue stiffening. Digital rectal examination is based on manually palpating the prostate tissue via the rectum. This test lacks sufficient accuracy required for early diagnosis which is necessary for effective management of prostate cancer. To develop an effective prostate cancer diagnostic technique, the authors propose an imaging technique that maps the distribution of the relative prostate tissue's elasticity modulus. Unlike digital rectal examination, this technique is quantitative, capable of accurately detecting small prostate lesions that cannot be sensed by manual palpation, and its accuracy is independent of the physician's experience. The proposed technique is a quasistatic elastography technique which uses ultrasound imaging to acquire tissue displacements resulting from transrectal ultrasound mechanical stimulation. The system involves a standard ultrasound imaging unit with accessibility to its radiofrequency data. The displacements are used as data for the tissue elasticity reconstruction. This reconstruction does not require tissue segmentation and is based on physics governing tissue mechanics. It is formulated using an inverse problem framework where elastic tissue deformation equations are fully inverted using an iterative scheme where each iteration involves stress calculation followed by elastic modulus updating until convergence is achieved.In silico and tissue mimicking phantom studies were conducted to validate the proposed technique, followed by a clinical pilot study involving two prostate cancer patients with whole-mount histopathology analysis on prostatectomy specimens to confirm a cancer location. The phantom studies demonstrated robustness and reasonably high accuracy of the proposed method. Obtained Young's modulus ratios indicated reconstruction errors of less than 12%. Reconstructed elastic modulus images of the two

  7. Evaluation of cervical stiffness during pregnancy using semiquantitative ultrasound elastography

    PubMed Central

    Hernandez-Andrade, Edgar; Hassan, Sonia S; Ahn, Hyunyoung; Korzeniewski, Steven J.; Yeo, Lami; Chaiworapongsa, Tinnakorn; Romero, Roberto

    2014-01-01

    Objective To evaluate cervical stiffness during pregnancy using ultrasound-derived elastography, a method used to estimate the average tissue displacement (strain) on a defined region of interest when oscillatory compression is applied. Methods Strain was calculated in two regions of interest, the endocervical canal and the entire cervix, from three anatomical planes of the cervix: mid-sagittal in the plane used for cervical length measurement, and in cross-sectional planes located at the internal and external cervical os. Associations between strain values, method of ascertainment and patient characteristics were assessed using linear mixed models to account for within-subject correlation. Inter-rater agreement in defining the degree of cervical stiffness was evaluated in 120 regions of interest acquired by two operators in 20 patients. Results A total of 1557 strain estimations were performed in 262 patients at 8-40 weeks of gestation. Adjusting for other sources of variation, 1) cervical tissue strain estimates obtained in the endocervical canal were on average 33% greater than those obtained in the entire cervix; 2) measures obtained in the cross-sectional plane of the external cervical os and sagittal plane were 45% and 13% greater compared to those measured in the cross-sectional plane of the internal cervical os, respectively; 3) mean strain rate was 14% and 5% greater among multiparous women with and without a history of preterm delivery compared to nulliparous women, respectively, and was on average 13% greater among women with a cervical length between 25-30mm compared to those with a cervical length >30mm; and 4) cervical tissue strain was more strongly associated with cervical length than with gestational age. Conclusion Semiquantitative elastography can be employed to evaluate changes in cervical stiffness during pregnancy. PMID:23151941

  8. WFUMB Guidelines and Recommendations on the Clinical Use of Ultrasound Elastography: Part 4. Thyroid.

    PubMed

    Cosgrove, David; Barr, Richard; Bojunga, Joerg; Cantisani, Vito; Chammas, Maria Cristina; Dighe, Manjiri; Vinayak, Sudhir; Xu, Jun-Mei; Dietrich, Christoph F

    2017-01-01

    The World Federation for Ultrasound in Medicine and Biology (WFUMB) has produced guidelines for the use of elastography techniques including basic science, breast and liver. Here we present elastography in thyroid diseases. For each available technique, procedure, reproducibility, results and limitations are analyzed and recommendations are given. Finally, recommendations are given based on the level of evidence of the published literature and on the WFUMB expert group's consensus. The document has a clinical perspective and is aimed at assessing the usefulness of elastography in the management of thyroid diseases.

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

    PubMed Central

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

    2014-01-01

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

  10. Reliability and Validity of Quantifying Absolute Muscle Hardness Using Ultrasound Elastography

    PubMed Central

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

    2012-01-01

    Muscle hardness is a mechanical property that represents transverse muscle stiffness. A quantitative method that uses ultrasound elastography for quantifying absolute human muscle hardness has been previously devised; however, its reliability and validity have not been completely verified. This study aimed to verify the reliability and validity of this quantitative method. The Young’s moduli of seven tissue-mimicking materials (in vitro; Young’s modulus range, 20–80 kPa; increments of 10 kPa) and the human medial gastrocnemius muscle (in vivo) were quantified using ultrasound elastography. On the basis of the strain/Young’s modulus ratio of two reference materials, one hard and one soft (Young’s moduli of 7 and 30 kPa, respectively), the Young’s moduli of the tissue-mimicking materials and medial gastrocnemius muscle were calculated. The intra- and inter-investigator reliability of the method was confirmed on the basis of acceptably low coefficient of variations (≤6.9%) and substantially high intraclass correlation coefficients (≥0.77) obtained from all measurements. The correlation coefficient between the Young’s moduli of the tissue-mimicking materials obtained using a mechanical method and ultrasound elastography was 0.996, which was equivalent to values previously obtained using magnetic resonance elastography. The Young’s moduli of the medial gastrocnemius muscle obtained using ultrasound elastography were within the range of values previously obtained using magnetic resonance elastography. The reliability and validity of the quantitative method for measuring absolute muscle hardness using ultrasound elastography were thus verified. PMID:23029231

  11. Current Status of Interventional Endoscopic Ultrasound.

    PubMed

    Ryozawa, Shomei; Fujita, Naotaka; Irisawa, Atsushi; Hirooka, Yoshiki; Mine, Tetsuya

    2017-03-20

    Endoscopic ultrasound (EUS) is being used increasingly in the management of pancreatic fluid collection, biliary and pancreatic duct drainage in cases of failed endoscopic retrograde cholangiopancreatography, drainage of the gallbladder, and other conditions. The role of interventional EUS is rapidly expanding and new interventions are continuously emerging. The development of devices could be a major breakthrough in the field of interventional EUS. New devices would enable the expansion of its role even further and prompt its widespread use in clinical practice. This review focuses on the current status of interventional EUS, especially highlighting the topics that are drawing endoscopists' interest at present. This article is protected by copyright. All rights reserved.

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

    NASA Astrophysics Data System (ADS)

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

    2012-02-01

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

  13. Ultrasound elastography assessment of the median nerve in leprosy patients.

    PubMed

    Nogueira-Barbosa, Marcello H; Lugão, Helena B; Gregio-Júnior, Everaldo; Crema, Michel D; Kobayashi, Mariana T T; Frade, Marco A C; Pavan, Theo Z; Carneiro, Antonio A O

    2017-09-01

    We sought to compare median nerve elasticity between leprosy patients (LPs) and healthy volunteers (HVs) using ultrasound elastography (UE). Two radiologists independently measured the strain ratio of the median nerve/flexor digitorum superficialis muscle (MN/FDSM) of 18 LP and 18 HV using real-time freehand UE. Statistical analysis included intra-class correlation coefficients (ICC) and Mann-Whitney test. The MN/FDSM strain ratios of the LP and HV were 2.66 ± 1.30 and 3.52 ± 0.93, respectively (P <  0.05). We observed a significantly lower MN/FDSM strain ratio in LP with reactions (types 1 and 2 cutaneous reactions associated with or without neuritis) (2.30 ± 0.91) compared with LP without reactions (3.60 ± 1.70). We found no significant differences between HV and LP without reactions. The intra- and inter-observer ICCs were 0.50 (95% confidence interval [CI], 0.11-0.72) and 0.34 (95% CI, 0.28-0.52), respectively. MN/FDSM strain ratios were significantly lower in LP with reactions. UE may be useful for nerve elasticity evaluation in leprosy. Muscle Nerve 56: 393-398, 2017. © 2016 Wiley Periodicals, Inc.

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

    PubMed

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

    2014-07-01

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

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

    PubMed

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

    2014-09-01

    The B-mode ultrasound image that can measure muscle architecture is displayed side by side with the ultrasound strain elastogram that can assess muscle hardness. Consequently, muscle architecture can be measured concurrently with muscle hardness using ultrasound strain elastography. To demonstrate the measurement of muscle architecture concurrently with muscle hardness using ultrasound strain elastography. Concurrent measurements of muscle architectural parameters (muscle thickness, pennation angle, and fascicle length) and muscle hardness of the medial gastrocnemius were performed with ultrasound strain elastography. Separate measurements of the muscle architectural parameters were also performed for use as reference values for the concurrent measurements. Both types of measurements were performed twice at 20° dorsiflexion, neutral position, and 30° plantar flexion. Coefficients of variance of the muscle architectural parameters obtained from the concurrent measurements (≤7.6%) were significantly higher than those obtained from the separate measurements (≤2.4%) (all P < 0.05). Intraclass correlation coefficients of the architectural parameters were lower in the concurrent measurements (≥0.74) than in the separate measurements (≥0.97). However, there were no significant differences in any muscle architectural parameters between the concurrent and separate measurements (all P > 0.05). The use of ultrasound strain elastography for the concurrent measurement of muscle architecture and muscle hardness is feasible. © The Foundation Acta Radiologica 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

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

    PubMed Central

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

    2014-01-01

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

  17. Ultrasound elastography: the new frontier in direct measurement of muscle stiffness.

    PubMed

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

    2014-11-01

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

  18. Ultrahigh resolution optical coherence elastography combined with a rigid micro-endoscope (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Fang, Qi; Curatolo, Andrea; Wijesinghe, Philip; Hamzah, Juliana; Ganss, Ruth; Noble, Peter B.; Karnowski, Karol; Sampson, David D.; Kim, Jun Ki; Lee, Wei M.; Kennedy, Brendan F.

    2017-02-01

    The mechanical forces that living cells experience represent an important framework in the determination of a range of intricate cellular functions and processes. Current insight into cell mechanics is typically provided by in vitro measurement systems; for example, atomic force microscopy (AFM) measurements are performed on cells in culture or, at best, on freshly excised tissue. Optical techniques, such as Brillouin microscopy and optical elastography, have been used for ex vivo and in situ imaging, recently achieving cellular-scale resolution. The utility of these techniques in cell mechanics lies in quick, three-dimensional and label-free mechanical imaging. Translation of these techniques toward minimally invasive in vivo imaging would provide unprecedented capabilities in tissue characterization. Here, we take the first steps along this path by incorporating a gradient-index micro-endoscope into an ultrahigh resolution optical elastography system. Using this endoscope, a lateral resolution of 2 µm is preserved over an extended depth-of-field of 80 µm, achieved by Bessel beam illumination. We demonstrate this combined system by imaging stiffness of a silicone phantom containing stiff inclusions and a freshly excised murine liver tissue. Additionally, we test this system on murine ribs in situ. We show that our approach can provide high quality extended depth-of-field images through an endoscope and has the potential to measure cell mechanics deep in tissue. Eventually, we believe this tool will be capable of studying biological processes and disease progression in vivo.

  19. Effect of bone-soft tissue friction on ultrasound axial shear strain elastography

    NASA Astrophysics Data System (ADS)

    Tang, Songyuan; Chaudhry, Anuj; Kim, Namhee; Reddy, J. N.; Righetti, Raffaella

    2017-08-01

    Bone-soft tissue friction is an important factor affecting several musculoskeletal disorders, frictional syndromes and the ability of a bone fracture to heal. However, this parameter is difficult to determine using non-invasive imaging modalities, especially in clinical settings. Ultrasound axial shear strain elastography is a non-invasive imaging modality that has been used in the recent past to estimate the bonding between different tissue layers. As most elastography methods, axial shear strain elastography is primarily used in soft tissues. More recently, this technique has been proposed to assess the bone-soft tissue interface. In this paper, we investigate the effect of a variation in bone-soft tissue friction coefficient in the resulting axial shear strain elastograms. Finite element poroelastic models of bone specimens exhibiting different bone-soft tissue friction coefficients were created and mechanically analyzed. These models were then imported to an ultrasound elastography simulation module to assess the presence of axial shear strain patterns. In vitro experiments were performed to corroborate selected simulation results. The results of this study show that the normalized axial shear strain estimated at the bone-soft tissue interface is statistically correlated to the bone-soft tissue coefficient of friction. This information may prove useful to better interpret ultrasound elastography results obtained in bone-related applications and, possibly, monitor bone healing.

  20. Validity of Measurement of Shear Modulus by Ultrasound Shear Wave Elastography in Human Pennate Muscle

    PubMed Central

    Miyamoto, Naokazu; Hirata, Kosuke; Kanehisa, Hiroaki; Yoshitake, Yasuhide

    2015-01-01

    Ultrasound shear wave elastography is becoming a valuable tool for measuring mechanical properties of individual muscles. Since ultrasound shear wave elastography measures shear modulus along the principal axis of the probe (i.e., along the transverse axis of the imaging plane), the measured shear modulus most accurately represents the mechanical property of the muscle along the fascicle direction when the probe’s principal axis is parallel to the fascicle direction in the plane of the ultrasound image. However, it is unclear how the measured shear modulus is affected by the probe angle relative to the fascicle direction in the same plane. The purpose of the present study was therefore to examine whether the angle between the principal axis of the probe and the fascicle direction in the same plane affects the measured shear modulus. Shear modulus in seven specially-designed tissue-mimicking phantoms, and in eleven human in-vivo biceps brachii and medial gastrocnemius were determined by using ultrasound shear wave elastography. The probe was positioned parallel or 20° obliquely to the fascicle across the B-mode images. The reproducibility of shear modulus measurements was high for both parallel and oblique conditions. Although there was a significant effect of the probe angle relative to the fascicle on the shear modulus in human experiment, the magnitude was negligibly small. These findings indicate that the ultrasound shear wave elastography is a valid tool for evaluating the mechanical property of pennate muscles along the fascicle direction. PMID:25853777

  1. Accuracy of localization of prostate lesions using manual palpation and ultrasound elastography

    NASA Astrophysics Data System (ADS)

    Kut, Carmen; Schneider, Caitlin; Carter-Monroe, Naima; Su, Li-Ming; Boctor, Emad; Taylor, Russell

    2009-02-01

    Purpose: To compare the accuracy of detecting tumor location and size in the prostate using both manual palpation and ultrasound elastography (UE). Methods: Tumors in the prostate were simulated using both synthetic and ex vivo tissue phantoms. 25 participants were asked to provide the presence, size and depth of these simulated lesions using manual palpation and UE. Ultrasound images were captured using a laparoscopic ultrasound probe, fitted with a Gore-Tetrad transducer with frequency of 7.5 MHz and a RF capture depth of 4-5 cm. A MATLAB GUI application was employed to process the RF data for ex vivo phantoms, and to generate UE images using a cross-correlation algorithm. Ultrasonix software was used to provide real time elastography during laparoscopic palpation of the synthetic phantoms. Statistical analyses were performed based on a two-tailed, student t-test with α = 0.05. Results: UE displays both a higher accuracy and specificity in tumor detection (sensitivity = 84%, specificity = 74%). Tumor diameters and depths are better estimated using ultrasound elastography when compared with manual palpation. Conclusions: Our results indicate that UE has strong potential in assisting surgeons to intra-operatively evaluate the tumor depth and size. We have also demonstrated that ultrasound elastography can be implemented in a laparoscopic environment, in which manual palpation would not be feasible. With further work, this application can provide accurate and clinically relevant information for surgeons during prostate resection.

  2. Lung Ultrasound Surface Wave Elastography: A Pilot Clinical Study.

    PubMed

    Zhang, Xiaoming; Osborn, Thomas; Zhou, Boran; Meixner, Duane; Kinnick, Randall R; Bartholmai, Brian; Greenleaf, James F; Kalra, Sanjay

    2017-09-01

    A lung ultrasound surface wave elastography (LUSWE) technique is developed to measure superficial lung tissue elastic properties. The purpose of this paper was to translate LUSWE into clinical studies for assessing patients with interstitial lung disease (ILD) and present the pilot data from lung measurements on 10 healthy subjects and 10 patients with ILD. ILD includes multiple lung disorders in which the lung tissue is distorted and stiffened by tissue fibrosis. Chest radiography and computed tomography are the most commonly used techniques for assessing lung disease, but they are associated with radiation and cannot directly measure lung elastic properties. LUSWE provides a noninvasive and nonionizing technique to measure the elastic properties of superficial lung tissue. LUSWE was used to measure regions of both lungs through six intercostal spaces for patients and healthy subjects. The data are presented as wave speed at 100, 150, and 200 Hz at the six intercostal spaces. As an example, the surface wave speeds are, respectively, 1.88 ± 0.11 m/s at 100 Hz, 2.74 ± 0.26 m/s at 150 Hz, and 3.62 ± 0.13 m/s at 200 Hz for a healthy subject in the upper right lung; this is in comparison to measurements from an ILD patient of 3.3 ± 0.37 m/s at 100 Hz, 4.38 ± 0.33 m/s at 150 Hz, and 5.24 ± 0.44 m/s at 200 Hz in the same lung space. Significant differences in wave speed between healthy subjects and ILD patients were found. LUSWE is a safe and noninvasive technique which may be useful for assessing ILD.

  3. Reality named endoscopic ultrasound biliary drainage.

    PubMed

    Guedes, Hugo Gonçalo; Lopes, Roberto Iglesias; de Oliveira, Joel Fernandez; Artifon, Everson Luiz de Almeida

    2015-10-25

    Endoscopic ultrasound (EUS) is used for diagnosis and evaluation of many diseases of the gastrointestinal (GI) tract. In the past, it was used to guide a cholangiography, but nowadays it emerges as a powerful therapeutic tool in biliary drainage. The aims of this review are: outline the rationale for endoscopic ultrasound-guided biliary drainage (EGBD); detail the procedural technique; evaluate the clinical outcomes and limitations of the method; and provide recommendations for the practicing clinician. In cases of failed endoscopic retrograde cholangiopancreatography (ERCP), patients are usually referred for either percutaneous transhepatic biliary drainage (PTBD) or surgical bypass. Both these procedures have high rates of undesirable complications. EGBD is an attractive alternative to PTBD or surgery when ERCP fails. EGBD can be performed at two locations: transhepatic or extrahepatic, and the stent can be inserted in an antegrade or retrograde fashion. The drainage route can be transluminal, duodenal or transpapillary, which, again, can be antegrade or retrograde [rendezvous (EUS-RV)]. Complications of all techniques combined include pneumoperitoneum, bleeding, bile leak/peritonitis and cholangitis. We recommend EGBD when bile duct access is not possible because of failed cannulation, altered upper GI tract anatomy, gastric outlet obstruction, a distorted ampulla or a periampullary diverticulum, as a minimally invasive alternative to surgery or radiology.

  4. Improving B mode ultrasound evaluation of breast lesions with real-time ultrasound elastography--a clinical approach.

    PubMed

    Tan, S M; Teh, H S; Mancer, J F Kent; Poh, W T

    2008-06-01

    Ultrasound elastography using the extended combined auto-correlation method of tissue elasticity allows for real-time strain image visualisation using a free-hand probe with concurrent conventional B mode imaging. Four hundred and fifteen consecutive women with 550 breast lesions confirmed on B mode ultrasound were assessed with elastography using the elasticity score. There were 119 malignant and 431 benign lesions. The elastography sensitivity was 78.0%, specificity was 98.5% and overall accuracy was 93.8%. The median score for malignancy was 5 and that for benign lesions was 2. There was good correlation with B mode BIRADS category. 98.6% of lesions with an elasticity score of 2 or below (95%CI=96.8-99.4) were benign. BIRADS 3 lesions with an elasticity score of 2 or below may be re-classified as BIRADS 2 lesions. We found that 15.3% of BIRADS 2 and 3 lesions with an elasticity score of 3 were malignant. Real-time ultrasound elastography is user-friendly with a high accuracy rate, thereby improving B mode ultrasound assessment.

  5. Value of Strain Elastography Ultrasound in Differentiation of Breast Masses and Histopathologic Correlation

    PubMed Central

    Atabey, Aysun Okar; Arıbal, Erkin; Ergelen, Rabia; Kaya, Handan

    2014-01-01

    Objective US elastography is an emerging technique that can be used during breast US examination. The increasing awareness of breast cancer led to an increase in mammography and breast US examinations. The specificity of these techniques is not high enough to prevent unnecessary biopsies. There is still a need for a more specific technique that can overcome this problem. This study aimed to evaluate the value of strain elastography in breast lesions. Materials and Methods In this study, 110 lesions of 96 patients were evaluated with strain elastography. Five score system was used for lesion scoring. The histopathologic results of lesions were obtained and were accepted as gold standard. The sensitivity, specificity, PPV and NPV of the technique were calculated. Histopathologic and strain elastography results were correlated. Results The sensitivity of US strain elastography was calculated as 83%, the specificity as 89%, the positive predictive value as 79% and the negative predictive value as 91%. There were no score 1 lesions. All score 2 lesions were benign. Score 5 had the highest true positivity rate. Conclusion We believe that ultrasound elastography is an effective imaging technique that can be used as an adjunct for differential diagnosis, prior to the decision to biopsy a lesion in certain cases.

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

    PubMed Central

    2014-01-01

    Accurate assessment of the degree of liver fibrosis is important for estimating prognosis and deciding on an appropriate course of treatment for cases of chronic liver disease (CLD) with various etiologies. Because of the inherent limitations of liver biopsy, there is a great need for non-invasive and reliable tests that accurately estimate the degree of liver fibrosis. Ultrasound (US) elastography is considered a non-invasive, convenient, and precise technique to grade the degree of liver fibrosis by measuring liver stiffness. There are several commercial types of US elastography currently in use, namely, transient elastography, acoustic radiation force impulse imaging, supersonic shear-wave imaging, and real-time tissue elastography. Although the low reproducibility of measurements derived from operator-dependent performance remains a significant limitation of US elastography, this technique is nevertheless useful for diagnosing hepatic fibrosis in patients with CLD. Likewise, US elastography may also be used as a convenient surveillance method that can be performed by physicians at the patients’ bedside to enable the estimation of the prognosis of patients with fatal complications related to CLD in a non-invasive manner. PMID:25038804

  7. Hydatid Cyst Diagnosed by Endoscopic Ultrasound.

    PubMed

    Castro-Poças, F; Araújo, Tarcísio; Coelho, André; Silva, Donzilia; Pedroto, Isabel

    2016-01-01

    A 69-year-old female with unremarkable past history underwent endoscopy for dyspepsia. She denied weight loss or anorexia. Upper endoscopy revealed a bulge in the lesser curvature and posterior wall of the stomach with 4-5 cm. Endoscopic ultrasound was performed which showed a heterogeneous lesion, anechogenic in the major part, with a floating membrane inside, the greatest diameter of 90.8 × 17.2 mm, originated in the left liver lobe. Surgical resection was performed. Pathologic examination revealed a cystic lesion with an acellular thick fibrous wall, surrounded by a conspicuous inflammatory reaction. The cyst wall revealed a characteristic lamellar pattern of the fibers. In the internal surface of the lesion, there were remains of membranous structures, amidst which a vestigial Protoscolex was noted. In the presented case, a floating membrane was observed, which is a pathognomonic feature, establishing the diagnosis of hydatid cyst type 3. Fine needle aspiration guided by ultrasound was not performed due to the certainty in the diagnosis. To the authors' knowledge, these are the first images by endoscopic ultrasound of hydatid cyst of liver presented as a bulge in the stomach with pathognomonic features, which allowed the definitive diagnosis with no need for further diagnostic tests.

  8. Accuracy of ultrasound elastography in the diagnosis of thyroid cancer in a low-risk population.

    PubMed

    Vidal-Casariego, A; López-González, L; Jiménez-Pérez, A; Ballesteros-Pomar, M D; Kyriakos, G; Urioste-Fondo, A; Álvarez-San Martín, R; Cano-Rodríguez, I; Jiménez-García de la Marina, J M

    2012-11-01

    Stiffness has been associated to malignancy in prostate and breast, as well as thyroid. Ultrasound elastography objectively measures tissue elasticity, and previous studies have described it as a high sensitivity and specificity technique for the detection of malignant thyroid nodules in high-risk populations. The aim was to assess the accuracy of elastography in a population with low risk of malignancy. 128 consecutive patients with nodular goiter were recruited. Elastography and ultrasound-guided fine-needle aspiration were performed. When malignancy was suspected by citology, surgery was recommended. Thyroid nodules were classified by elastography according the criteria described by Ueno, and an alternative classification. Sensitivity, specificity, predictive values, and odds ratio were calculated. Most patients were female, aged 56.1 year, with single nodule (52.0%) or multinodular goiter (45.6%), and a few thyroiditis (2.4%). The majority of nodules were mostly elastic. Fine-needle aspiration found 86% of benign nodules, 9.3% of indeterminate, and 4.7% possibly malignant. After surgery, 3 malignant nodules were confirmed, all of them being papillary carcinomas. All the malignant nodules were mostly elastic, as well as 75% of indeterminate nodules. Low values of sensitivity and specificity were found for elastic nodules being benign and hard nodules malignant. In a low-risk population for thyroid cancer, elastography lacks accuracy for the diagnosis of malignant nodules. © J. A. Barth Verlag in Georg Thieme Verlag KG Stuttgart · New York.

  9. Ultrasound-based elastography for the diagnosis of portal hypertension in cirrhotics

    PubMed Central

    Şirli, Roxana; Sporea, Ioan; Popescu, Alina; Dănilă, Mirela

    2015-01-01

    Progressive fibrosis is encountered in almost all chronic liver diseases. Its clinical signs are diagnostic in advanced cirrhosis, but compensated liver cirrhosis is harder to diagnose. Liver biopsy is still considered the reference method for staging the severity of fibrosis, but due to its drawbacks (inter and intra-observer variability, sampling errors, unequal distribution of fibrosis in the liver, and risk of complications and even death), non-invasive methods were developed to assess fibrosis (serologic and elastographic). Elastographic methods can be ultrasound-based or magnetic resonance imaging-based. All ultrasound-based elastographic methods are valuable for the early diagnosis of cirrhosis, especially transient elastography (TE) and acoustic radiation force impulse (ARFI) elastography, which have similar sensitivities and specificities, although ARFI has better feasibility. TE is a promising method for predicting portal hypertension in cirrhotic patients, but it cannot replace upper digestive endoscopy. The diagnostic accuracy of using ARFI in the liver to predict portal hypertension in cirrhotic patients is debatable, with controversial results in published studies. The accuracy of ARFI elastography may be significantly increased if spleen stiffness is assessed, either alone or in combination with liver stiffness and other parameters. Two-dimensional shear-wave elastography, the ElastPQ technique and strain elastography all need to be evaluated as predictors of portal hypertension. PMID:26556985

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

    PubMed

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

    2016-02-01

    Ultrasound-based carotid elastography has been developed to estimate the mechanical properties of atherosclerotic plaques. The objective of this study was to evaluate the in vivo capability of carotid elastography in vulnerable plaque detection using high-resolution magnetic resonance imaging as reference. Ultrasound radiofrequency data of 46 carotid plaques from 29 patients (74 ± 5 y old) were acquired and inter-frame axial strain was estimated with an optical flow method. The maximum value of absolute strain rate for each plaque was derived as an indicator for plaque classification. Magnetic resonance imaging of carotid arteries was performed on the same patients to classify the plaques into stable and vulnerable groups for carotid elastography validation. The maximum value of absolute strain rate was found to be significantly higher in vulnerable plaques (2.15 ± 0.79 s(-1), n = 27) than in stable plaques (1.21 ± 0.37 s(-1), n = 19) (p < 0.0001). Receiver operating characteristic curve analysis was performed, and the area under the curve was 0.848. Therefore, the in vivo capability of carotid elastography to detect vulnerable plaques, validated by magnetic resonance imaging, was proven, revealing the potential of carotid elastography as an important tool in atherosclerosis assessment and stroke prevention.

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

    PubMed Central

    Li, Qiang; Chen, Pin-Yu; Wang, Chiao-Yin; Liu, Hao-Li; Teng, Jianfu

    2014-01-01

    Percutaneous radiofrequency ablation (RFA) is a minimally invasive treatment to thermally destroy tumors. Ultrasound-based electrode-displacement elastography is an emerging technique for evaluating the region of RFA-induced lesions. The angle between the imaging probe and the RFA electrode can influence electrode-displacement elastography when visualizing the ablation zone. We explored the angle effect on electrode-displacement elastography to measure the ablation zone. Phantoms embedded with meatballs were fabricated and then ablated using an RFA system to simulate RFA-induced lesions. For each phantom, a commercial ultrasound scanner with a 7.5 MHz linear probe was used to acquire raw image data at different angles, ranging from 30° to 90° at increments of 10°, to construct electrode-displacement images and facilitate comparisons with tissue section images. The results revealed that the ablation regions detected using electrode-displacement elastography were highly correlated with those from tissue section images when the angle was between 30° and 60°. However, the boundaries of lesions were difficult to distinguish, when the angle was larger than 60°. The experimental findings suggest that angle selection should be considered to achieve reliable electrode-displacement elastography to describe ablation zones. PMID:24971347

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

    PubMed

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

    2016-09-01

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

  13. Quasi-static elastography and its application in investigation of focused ultrasound induced tissue lesions

    NASA Astrophysics Data System (ADS)

    Wang, Bin; Ling, Tao; Shen, Yong; Wang, Yan; Zheng, Hairong; Li, Faqi

    2012-10-01

    Monitoring of Focused Ultrasound (FUS) therapy has always been a key factor for a successful therapy. Although B-mode ultrasound has long been used for monitoring FUS therapy, the gray scale changes can not precisely reflect the lesion formation inside the tissue, while MR thermometry is considered to be too expensive. In this study, elastography had been performed using a commercial ultrasound system to investigate lesions produced by FUS irradiation in vitro. Several motion detection algorithms had been performed to improve the motion detection accuracy in the elastography. The effects of different algorithms on the motion detection accuracy were compared. Experimental results on the FUS induced lesion in swine muscle were introduced. The results indicated that lesions induced by small dosage of FUS inside the tissue can be successfully detected, which has a profound clinical meaning for the monitoring of FUS therapy.

  14. Ultrasound elastography of ethanol-induced hepatic lesions: in vitro study.

    PubMed

    Cui, Li-gang; Shao, Jin-hua; Wang, Jin-rui; Bai, Jing; Zhang, Yi-zhuo

    2009-06-01

    To study the value of ultrasound elastography in evaluation of ethanol-induced lesions of liver. Alcohol with a dose of 2 ml was injected into a fresh porcine liver under ultrasound guidance to create stiff necrosis. Then freehand elastography of the lesion from the identical scan plane was obtained with SONOLINE Antares system using VF10-5 probe at about every 30 seconds till 6 minutes later. The original high quality radiofrequency data were acquired through an ultrasound research interface which was provided by the ultrasound system. Then, corresponding elastograms were produced offline using cross-correlation technique and compared with gross pathology findings. Gray-scale sonogram showed a hyperechoic area with acoustic shadow below appeared immediately after alcohol injection. The hyperechoic area tended to be diffuse and its boundary to be illegible with time. On the contrary, the ethanol-induced lesion in elastogram appeared as a low strain hard region surrounded by high strain soft hepatic tissues, with clear but irregular boundaries. Sequential elastograms with the sketched lesion boundaries showed that the lesion area increased in the first 3 minutes after ethanol injection, and then reached a plateau which corresponding to gross specimen. Ultrasound elastography is capable of detecting and evaluating the diffusion of ethanol-induced hepatic lesion, and more sensitive and accurate than routine sonography.

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

    PubMed Central

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

    2014-01-01

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

  16. Advances in endoscopic ultrasound imaging of colorectal diseases.

    PubMed

    Cârțână, Elena Tatiana; Gheonea, Dan Ionuț; Săftoiu, Adrian

    2016-02-07

    The development of endoscopic ultrasound (EUS) has had a significant impact for patients with digestive diseases, enabling enhanced diagnostic and therapeutic procedures, with most of the available evidence focusing on upper gastrointestinal (GI) and pancreatico-biliary diseases. For the lower GI tract the main application of EUS has been in staging rectal cancer, as a complementary technique to other cross-sectional imaging methods. EUS can provide highly accurate in-depth assessments of tumour infiltration, performing best in the diagnosis of early rectal tumours. In the light of recent developments other EUS applications for colorectal diseases have been also envisaged and are currently under investigation, including beyond-rectum tumour staging by means of the newly developed forward-viewing radial array echoendoscope. Due to its high resolution, EUS might be also regarded as an ideal method for the evaluation of subepithelial lesions. Their differential diagnosis is possible by imaging the originating wall layer and the associated echostructure, and cytological and histological confirmation can be obtained through EUS-guided fine needle aspiration or trucut biopsy. However, reports on the use of EUS in colorectal subepithelial lesions are currently limited. EUS allows detailed examination of perirectal and perianal complications in Crohn's disease and, as a safe and less expensive investigation, can be used to monitor therapeutic response of fistulae, which seems to improve outcomes and reduce the need for additional surgery. Furthermore, EUS image enhancement techniques, such as the use of contrast agents or elastography, have recently been evaluated for colorectal indications as well. Possible applications of contrast enhancement include the assessment of tumour angiogenesis in colorectal cancer, the monitoring of disease activity in inflammatory bowel disease based on quantification of bowel wall vascularization, and differentiating between benign and

  17. Ultrasound Shear Wave Elastography: A Novel Method to Evaluate Bladder Pressure.

    PubMed

    Sturm, Renea M; Yerkes, Elizabeth B; Nicholas, Jennifer L; Snow-Lisy, Devon; Diaz Saldano, Dawn; Gandor, P Lacy; Halline, Christopher G; Rosoklija, Ilina; Rychlik, Karen; Johnson, Emilie K; Cheng, Earl Y

    2017-03-31

    Children with bladder dysfunction resulting in increased storage pressure are at risk for renal deterioration. The current gold standard for evaluation of bladder pressure is urodynamics, an invasive test requiring catheterization. We evaluated ultrasound shear wave elastography as a novel means of assessing bladder biomechanical properties associated with increased bladder pressure. Concurrent shear wave elastography and urodynamics were performed. Ultrasound shear wave elastography images were obtained of the anterior and posterior wall when empty and at 25%, 50%, 75% and 100% expected bladder capacity, and end fill volume. Regions of interest were confirmed by a pediatric radiologist. Bladder cohorts were defined as compliant (capacity detrusor pressure less than 25 cm H2O) and noncompliant (25 cm H2O or greater). Pearson correlation coefficients and a mixed effects model evaluated the relationship between shear wave speed and detrusor pressure, compliance and normalized compliance. An unpaired t-test was used for between cohort analyses. In all 23 subjects mean shear wave speed of the anterior and posterior bladder walls significantly correlated with detrusor pressure throughout filling. When comparing compliant and noncompliant bladders, mean shear wave speed and detrusor shear wave speed of the anterior wall significantly increased with filling of noncompliant bladders. Shear wave speed remained at baseline levels in compliant bladders. Mean shear wave speed of the anterior wall was significantly correlated with compliance and normalized compliance. Ultrasound shear wave elastography bladder measurements correlate well with bladder storage pressure, and shear wave speed measurements differ between compliant and noncompliant bladders. This is the first known study to demonstrate that shear wave elastography is promising as a bedside modality for the assessment of bladder dysfunction in children. Copyright © 2017 American Urological Association Education and

  18. Ultrasound elastography: efficient estimation of tissue displacement using an affine transformation model

    NASA Astrophysics Data System (ADS)

    Hashemi, Hoda Sadat; Boily, Mathieu; Martineau, Paul A.; Rivaz, Hassan

    2017-03-01

    Ultrasound elastography entails imaging mechanical properties of tissue and is therefore of significant clinical importance. In elastography, two frames of radio-frequency (RF) ultrasound data that are obtained while the tissue is undergoing deformation, and the time-delay estimate (TDE) between the two frames is used to infer mechanical properties of tissue. TDE is a critical step in elastography, and is challenging due to noise and signal decorrelation. This paper presents a novel and robust technique TDE using all samples of RF data simultaneously. We assume tissue deformation can be approximated by an affine transformation, and hence call our method ATME (Affine Transformation Model Elastography). The affine transformation model is utilized to obtain initial estimates of axial and lateral displacement fields. The affine transformation only has six degrees of freedom (DOF), and as such, can be efficiently estimated. A nonlinear cost function that incorporates similarity of RF data intensity and prior information of displacement continuity is formulated to fine-tune the initial affine deformation field. Optimization of this function involves searching for TDE of all samples of the RF data. The optimization problem is converted to a sparse linear system of equations, which can be solved in real-time. Results on simulation are presented for validation. We further collect RF data from in-vivo patellar tendon and medial collateral ligament (MCL), and show that ATME can be used to accurately track tissue displacement.

  19. Evaluation of Neoadjuvant Chemotherapy Response in Women with Locally Advanced Breast Cancer Using Ultrasound Elastography1

    PubMed Central

    Falou, Omar; Sadeghi-Naini, Ali; Prematilake, Sameera; Sofroni, Ervis; Papanicolau, Naum; Iradji, Sara; Jahedmotlagh, Zahra; Lemon-Wong, Sharon; Pignol, Jean-Philippe; Rakovitch, Eileen; Zubovits, Judit; Spayne, Jacqueline; Dent, Rebecca; Trudeau, Maureen; Boileau, Jean Francois; Wright, Frances C; Yaffe, Martin J; Czarnota, Gregory J

    2013-01-01

    PURPOSE: Ultrasound elastography is a new imaging technique that can be used to assess tissue stiffness. The aim of this study was to investigate the potential of ultrasound elastography for monitoring treatment response of locally advanced breast cancer patients undergoing neoadjuvant therapy. METHODS: Fifteen women receiving neoadjuvant chemotherapy had the affected breast scanned before, 1, 4, and 8 weeks following therapy initiation, and then before surgery. Changes in elastographic parameters related to tissue biomechanical properties were then determined and compared to clinical and pathologic tumor response after mastectomy. RESULTS: Patients who responded to therapy demonstrated a significant decrease (P < .05) in strain ratios and strain differences 4 weeks after treatment initiation compared to non-responding patients. Mean strain ratio and mean strain difference for responders was 81 ± 3% and 1 ± 17% for static regions of interest (ROIs) and 81 ± 3% and 6 ± 18% for dynamic ROIs, respectively. In contrast, these parameters were 102±2%, 110±17%, 101±4%, and 109±30% for non-responding patients, respectively. Strain ratio using static ROIs was found to be the best predictor of treatment response, with 100% sensitivity and 100% specificity obtained 4 weeks after starting treatment. CONCLUSIONS: These results suggest that ultrasound elastography can be potentially used as an early predictor of tumor therapy response in breast cancer patients. PMID:23418613

  20. Evaluation of neoadjuvant chemotherapy response in women with locally advanced breast cancer using ultrasound elastography.

    PubMed

    Falou, Omar; Sadeghi-Naini, Ali; Prematilake, Sameera; Sofroni, Ervis; Papanicolau, Naum; Iradji, Sara; Jahedmotlagh, Zahra; Lemon-Wong, Sharon; Pignol, Jean-Philippe; Rakovitch, Eileen; Zubovits, Judit; Spayne, Jacqueline; Dent, Rebecca; Trudeau, Maureen; Boileau, Jean Francois; Wright, Frances C; Yaffe, Martin J; Czarnota, Gregory J

    2013-02-01

    Ultrasound elastography is a new imaging technique that can be used to assess tissue stiffness. The aim of this study was to investigate the potential of ultrasound elastography for monitoring treatment response of locally advanced breast cancer patients undergoing neoadjuvant therapy. Fifteen women receiving neoadjuvant chemotherapy had the affected breast scanned before, 1, 4, and 8 weeks following therapy initiation, and then before surgery. Changes in elastographic parameters related to tissue biomechanical properties were then determined and compared to clinical and pathologic tumor response after mastectomy. Patients who responded to therapy demonstrated a significant decrease (P < .05) in strain ratios and strain differences 4 weeks after treatment initiation compared to non-responding patients. Mean strain ratio and mean strain difference for responders was 81 ± 3% and 1 ± 17% for static regions of interest (ROIs) and 81 ± 3% and 6 ± 18% for dynamic ROIs, respectively. In contrast, these parameters were 102±2%, 110±17%, 101±4%, and 109±30% for non-responding patients, respectively. Strain ratio using static ROIs was found to be the best predictor of treatment response, with 100% sensitivity and 100% specificity obtained 4 weeks after starting treatment. These results suggest that ultrasound elastography can be potentially used as an early predictor of tumor therapy response in breast cancer patients.

  1. TRANSVERSUS ABDOMINIS ELASTICITY DURING VARIOUS EXERCISES: A SHEAR WAVE ULTRASOUND ELASTOGRAPHY STUDY.

    PubMed

    Hirayama, Kuniaki; Akagi, Ryota; Moniwa, Yuki; Okada, Junichi; Takahashi, Hideyuki

    2017-08-01

    Although the transversus abdominis (TrA) is considered to play a significant role in maintaining trunk stability, there is little information regarding the type of exercise that best facilitates the development of tension in the TrA. Muscle elasticity shows a strong association with muscle tension. Shear wave ultrasound elastography provides a means by which the tension of TrA can be noninvasively estimated, by quantifying it's elasticity. The purpose of this study was to examine the TrA elasticity during several exercises as measured by shear wave ultrasound elastography, and to determine which of the studied exercises demonstrated the greatest tension. Ten healthy men performed abdominal hollowing, abdominal bracing, a hanging deadlift, elbow-toe plank with contralateral arm and leg lift, and back bridge with single leg lift. During these exercises, TrA elasticity was measured using ultrasound elastography. The same measurements were performed at rest before and after these exercises. No significant difference was found for rest conditions measured before and after the exercises (p = 0.63). Abdominal bracing showed a significantly higher elasticity value than the other exercises (p < 0.05), except for hanging deadlift. Among the exercises, abdominal bracing was the exercise that elevated the TrA tension the most. The present results also suggested that hanging deadlift also produced comparably high TrA tension with abdominal bracing. 2c.

  2. TRANSVERSUS ABDOMINIS ELASTICITY DURING VARIOUS EXERCISES: A SHEAR WAVE ULTRASOUND ELASTOGRAPHY STUDY

    PubMed Central

    Akagi, Ryota; Moniwa, Yuki; Okada, Junichi; Takahashi, Hideyuki

    2017-01-01

    Background Although the transversus abdominis (TrA) is considered to play a significant role in maintaining trunk stability, there is little information regarding the type of exercise that best facilitates the development of tension in the TrA. Muscle elasticity shows a strong association with muscle tension. Shear wave ultrasound elastography provides a means by which the tension of TrA can be noninvasively estimated, by quantifying it's elasticity. Purpose The purpose of this study was to examine the TrA elasticity during several exercises as measured by shear wave ultrasound elastography, and to determine which of the studied exercises demonstrated the greatest tension. Methods Ten healthy men performed abdominal hollowing, abdominal bracing, a hanging deadlift, elbow–toe plank with contralateral arm and leg lift, and back bridge with single leg lift. During these exercises, TrA elasticity was measured using ultrasound elastography. The same measurements were performed at rest before and after these exercises. Result No significant difference was found for rest conditions measured before and after the exercises (p = 0.63). Abdominal bracing showed a significantly higher elasticity value than the other exercises (p < 0.05), except for hanging deadlift. Conclusion Among the exercises, abdominal bracing was the exercise that elevated the TrA tension the most. The present results also suggested that hanging deadlift also produced comparably high TrA tension with abdominal bracing. Level of Evidence 2c PMID:28900566

  3. Object detection in ultrasound elastography for use in HIFU treatment of cancer

    NASA Astrophysics Data System (ADS)

    Huang, Alex; Mankani, Soumya; Choo, Chang

    2014-03-01

    High intensity focused ultrasound (HIFU), has applications in treating various cancers, such as prostate, liver and breast cancer. In order for HIFU to be effective and efficient it needs to be guided by an imaging modality. While there are several options for guiding HIFU treatment, one of the most promising is ultrasound elastography. Current commercial devices use Brightness-Mode (B-mode) imaging or MRI, and are manual processes. Ultrasound elastography, allows complete automation of HIFU treatment due to the enhanced image, that elastography provides. The elastic image provides more information and less noise. To show that segmentation was possible on elastic images, nine algorithms were implemented in matlab and used on three distinct images for object detection. The three images used, have varying properties regarding object intensity and placement, as well as different noise patterns. Using PSNR, to gauge the effectiveness of each algorithm, it was shown that segmentation was possible on all images using different algorithms. The bilateral-shock-bilateral algorithm proved to be an overall effective algorithm in every situation with a PSNR of 83.87db on the phantom image. The segmentation results clearly highlight any object in the images. Future work includes fine tuning the algorithm with different phantom images and in-vivo images to distinguish between noise and desired object.

  4. Differences in liver stiffness values obtained with new ultrasound elastography machines and Fibroscan: A comparative study.

    PubMed

    Piscaglia, Fabio; Salvatore, Veronica; Mulazzani, Lorenzo; Cantisani, Vito; Colecchia, Antonio; Di Donato, Roberto; Felicani, Cristina; Ferrarini, Alessia; Gamal, Nesrine; Grasso, Valentina; Marasco, Giovanni; Mazzotta, Elena; Ravaioli, Federico; Ruggieri, Giacomo; Serio, Ilaria; Sitouok Nkamgho, Joules Fabrice; Serra, Carla; Festi, Davide; Schiavone, Cosima; Bolondi, Luigi

    2017-07-01

    Whether Fibroscan thresholds can be immediately adopted for none, some or all other shear wave elastography techniques has not been tested. The aim of the present study was to test the concordance of the findings obtained from 7 of the most recent ultrasound elastography machines with respect to Fibroscan. Sixteen hepatitis C virus-related patients with fibrosis ≥2 and having reliable results at Fibroscan were investigated in two intercostal spaces using 7 different elastography machines. Coefficients of both precision (an index of data dispersion) and accuracy (an index of bias correction factors expressing different magnitudes of changes in comparison to the reference) were calculated. Median stiffness values differed among the different machines as did coefficients of both precision (range 0.54-0.72) and accuracy (range 0.28-0.87). When the average of the measurements of two intercostal spaces was considered, coefficients of precision significantly increased with all machines (range 0.72-0.90) whereas of accuracy improved more scatteredly and by a smaller degree (range 0.40-0.99). The present results showed only moderate concordance of the majority of elastography machines with the Fibroscan results, preventing the possibility of the immediate universal adoption of Fibroscan thresholds for defining liver fibrosis staging for all new machines. Copyright © 2017 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

  5. On the potential of ultrasound elastography for pressure ulcer early detection

    PubMed Central

    Deprez, Jean-François; Brusseau, Elisabeth; Fromageau, Jérémie; Cloutier, Guy; Basset, Olivier

    2011-01-01

    Purpose Pressure ulcers are areas of soft tissue breakdown induced by a sustained mechanical stress that damages the skin and underlying tissues. They represent a considerable burden to the society in terms of health care and cost. Yet, techniques for prevention and detection of pressure ulcers still remain very limited. In this article, the authors investigated the potential of ultrasound elastography for pressure ulcer early detection. Elastography is an imaging technique providing local information on biological tissue mechanical properties. It is relevant for pressure ulcer detection as this pathology is associated with a gradual stiffening of damaged tissues, beginning in the deeper tissues and progressing toward the skin surface. Methods A 2D ultrasound elastography method was proposed and its ability in terms of pressure ulcer detection was validated through numerical simulations and physical acquisitions on pressure ulcer mimicking phantoms. In vivo experiments on a rat model are also reported. A maintained pressure was applied on the animal thigh, with a view to generate a pressure ulcer, and ultrasound data were acquired and processed before and after application of this pressure. Results Numerical simulations demonstrated that a pressure ulcer can theoretically be detected at a very early stage with ultrasound elastography. Even when the ulcer region was characterized by a low stiffening (ratio of 1.8 relative to normal tissues), the corresponding elastogram clearly underlined the pathological area. This observation was confirmed by the results obtained on a physical phantom mimicking a pressure ulcer at an early stage. Computed elastograms showed strain differences between areas mimicking healthy and pathological tissues. Results corresponding to in vivo experiments revealed a difference in the way tissues behaved before and after the pressure was applied on the animal thigh, which strongly suggests the presence of a pathological area. Conclusions

  6. The use of 2D ultrasound elastography for measuring tendon motion and strain.

    PubMed

    Chernak Slane, Laura; Thelen, Darryl G

    2014-02-07

    The goal of the current study was to investigate the fidelity of a 2D ultrasound elastography method for the measurement of tendon motion and strain. Ultrasound phantoms and ex vivo porcine flexor tendons were cyclically stretched to 4% strain while cine ultrasound radiofrequency (RF) data and video data were simultaneously collected. 2D ultrasound elastography was used to estimate tissue motion and strain from RF data, and surface tissue motion and strain were separately estimated using digital image correlation (DIC). There were strong correlations (R(2)>0.97) between DIC and RF measurements of phantom displacement and strain, and good agreement in estimates of peak phantom strain (DIC: 3.5±0.2%; RF: 3.7±0.1%). For tendon, elastographic estimates of displacement profiles also correlated well with DIC measurements (R(2)>0.92), and exhibited similar estimated peak tendon strain (DIC: 2.6±1.4%; RF: 2.2±1.3%). Elastographic tracking with B-Mode images tended to under-predict peak strain for both the phantom and tendon. This study demonstrates the capacity to use quantitative elastographic techniques to measure tendon displacement and strain within an ultrasound image window. The approach may be extendible to in vivo use on humans, which would allow for the non-invasive analysis of tendon deformation in both normal and pathological states. © 2013 Elsevier Ltd. All rights reserved.

  7. The Use of 2D Ultrasound Elastography for Measuring Tendon Motion and Strain

    PubMed Central

    Slane, Laura Chernak; Thelen, Darryl G.

    2014-01-01

    The goal of the current study was to investigate the fidelity of a 2D ultrasound elastography method for the measurement of tendon motion and strain. Ultrasound phantoms and ex vivo porcine flexor tendons were cyclically stretched to 4% strain while cine ultrasound radiofrequency (RF) data and video data were simultaneously collected. 2D ultrasound elastography was used to estimate tissue motion and strain from RF data, and surface tissue motion and strain were separately estimated using digital image correlation (DIC). There were strong correlations (R2 > 0.97) between DIC and RF measurements of phantom displacement and strain, and good agreement in estimates of peak phantom strain (DIC: 3.5 ± 0.2%; RF: 3.7 ± 0.1%). For tendon, elastographic estimates of displacement profiles also correlated well with DIC measurements (R2 > 0.92), and exhibited similar estimated peak tendon strain (DIC: 2.6 ± 1.4%; RF: 2.2 ± 1.3%). Elastographic tracking with B-Mode images tended to under-predict peak strain for both the phantom and tendon. This study demonstrates the capacity to use quantitative elastographic techniques to measure tendon displacement and strain within an ultrasound image window. The approach may be extendible to in vivo use on humans, which would allow for the non-invasive analysis of tendon deformation in both normal and pathological states. PMID:24388164

  8. Tendon motion and strain patterns evaluated with two-dimensional ultrasound elastography

    PubMed Central

    Chernak, Laura A.; Thelen, Darryl G.

    2012-01-01

    The purpose of this study was to evaluate the use of 2D ultrasound elastography to assess tendon tissue motion and strains under axial loading conditions. Four porcine flexor tendons were cyclically loaded to 4% peak strain using a servo hydraulic test system. An ultrasound transducer was positioned to image a longitudinal cross-section of the tendon during loading. Ultrasound radiofrequency (RF) data were collected at 63 frames per second simultaneously with applied force and crosshead displacement. A grid of nodes was manually positioned on an ultrasound image of the unloaded tendon. Small kernels (2 × 1 mm) centered at each node were then cross-correlated with search regions centered at corresponding nodal locations in the subsequent frame. Frame-to-frame nodal displacements were defined as the values that maximized the normalized cross-correlations. This process was repeated across all frames in the loading cycle, providing a measurement of the 2D trajectories of tissue motion through out the loading cycle. The high resolution displacement measures along the RF beam direction were spatially differentiated to estimate the transverse (relative to tend on fibers) tissue strains. The nodal displacements obtained using this method were very repeatable, with average along-fiber trajectories that were highly correlated (r2>0.98) with the prescribed crosshead displacements. The elastography transverse strains were also repeatable and were consistent with average transverse strains estimated via changes in tendon width. The apparent Poisson’s ratios (0.82-1.64) exceeded the incompressibility limit, but are comparable to values found for tendon in prior experimental and computational studies. The results demonstrate that 2D ultrasound elastography is a promising approach for noninvasively assessing localized tissue motion and strain patterns. PMID:22939179

  9. Endoscopic ultrasound practice survey in latin america.

    PubMed

    Drigo, Juliana Marques; Castillo, Cecilia; Wever, Wallia; Obaldía, José Ricardo Ruíz; Fillipi, Sheila; Ribeiro, Manoel C S A; Rossini, Lucio G B

    2013-10-01

    Endoscopic ultrasound (EUS) has become an important imaging modality for the diagnosis, staging and treatment of gastrointestinal disorders. However, no official data exists regarding clinical EUS practice in Latin America (LA). This study assessed current EUS practice and training. A direct mail survey questionnaire was sent to 268 Capítulo Latino Americano de Ultrasonido Endoscópico members between August 2012 and January 2013. The questionnaire was sent out in English, Spanish and Portuguese languages and was available through the following site: http://www.cleus-encuesta.com. Responses were requested only from physicians who perform EUS. A total of 70 LA physicians answered the questionnaire until January 2013. Most of the participants were under 42 years of age (53%) and 80% were men. Most participants (45.7%) perform EUS in Brazil, 53% work in a private hospital. The majority (70%) also perform endoscopic retrograde cholangiopancreatography. A total 42% had performed EUS for 2 years or less and 22.7% for 11 years or more. Only 10% performed more than 5000 EUS. The most common indication was an evaluation of pancreatic-biliary-ampullary lesions. Regarding training, 48.6% had more than 6 months of dedicated hands-on EUS and 37% think that at least 6 months of formal training is necessary to acquire competence. Furthermore, 64% think that more than 50 procedures for pancreatic-biliary lesions are necessary. This survey provides insight into the status of EUS in LA. EUS is performed mostly by young endoscopists in LA. Diagnostic upper EUS is the most common EUS procedure. Most endosonographers believe that formal training is necessary to acquire competence.

  10. Endoscopic Ultrasound Practice Survey in Latin America

    PubMed Central

    Drigo, Juliana Marques; Castillo, Cecilia; Wever, Wallia; Obaldía, José Ricardo Ruíz; Fillipi, Sheila; Ribeiro, Manoel C. S. A.; Rossini, Lucio G. B.

    2013-01-01

    Objective: Endoscopic ultrasound (EUS) has become an important imaging modality for the diagnosis, staging and treatment of gastrointestinal disorders. However, no official data exists regarding clinical EUS practice in Latin America (LA). This study assessed current EUS practice and training. Patients and Methods: A direct mail survey questionnaire was sent to 268 Capítulo Latino Americano de Ultrasonido Endoscópico members between August 2012 and January 2013. The questionnaire was sent out in English, Spanish and Portuguese languages and was available through the following site: http://www.cleus-encuesta.com. Responses were requested only from physicians who perform EUS. Results: A total of 70 LA physicians answered the questionnaire until January 2013. Most of the participants were under 42 years of age (53%) and 80% were men. Most participants (45.7%) perform EUS in Brazil, 53% work in a private hospital. The majority (70%) also perform endoscopic retrograde cholangiopancreatography. A total 42% had performed EUS for 2 years or less and 22.7% for 11 years or more. Only 10% performed more than 5000 EUS. The most common indication was an evaluation of pancreatic-biliary-ampullary lesions. Regarding training, 48.6% had more than 6 months of dedicated hands-on EUS and 37% think that at least 6 months of formal training is necessary to acquire competence. Furthermore, 64% think that more than 50 procedures for pancreatic-biliary lesions are necessary. Conclusion: This survey provides insight into the status of EUS in LA. EUS is performed mostly by young endoscopists in LA. Diagnostic upper EUS is the most common EUS procedure. Most endosonographers believe that formal training is necessary to acquire competence. PMID:24949398

  11. Photoacoustic elastography.

    PubMed

    Hai, Pengfei; Yao, Junjie; Li, Guo; Li, Chiye; Wang, Lihong V

    2016-02-15

    Elastography can noninvasively map the elasticity distribution in biological tissue, which can potentially be used to reveal disease conditions. In this Letter, we have demonstrated photoacoustic elastography by using a linear-array photoacoustic computed tomography system. The feasibility of photoacoustic elastography was first demonstrated by imaging the strains of single-layer and bilayer gelatin phantoms with various stiffness values. The measured strains agreed well with theoretical values, with an average error of less than 5.2%. Next, in vivo photoacoustic elastography was demonstrated on a mouse leg, where the fat and muscle distribution was mapped based on the elasticity contrast. We confirmed the photoacoustic elastography results by ultrasound elastography performed simultaneously.

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

    NASA Astrophysics Data System (ADS)

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

    2017-01-01

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

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

    PubMed Central

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

    2015-01-01

    Tissue-engineered (TE) cartilage constructs tend to develop inhomogeneously, thus, to predict the mechanical performance of the tissue, conventional biomechanical testing, which yields average material properties, is of limited value. Rather, techniques for evaluating regional and depth-dependent properties of TE cartilage, preferably non-destructively, are required. The purpose of this study was to build upon our previous results and to investigate the feasibility of using ultrasound elastography to non-destructively assess the depth-dependent biomechanical characteristics of TE cartilage while in a sterile bioreactor. As a proof-of-concept, and to standardize an assessment protocol, a well-characterized three-layered hydrogel construct was used as a surrogate for TE cartilage, and was studied under controlled incremental compressions. The strain field of the construct predicted by elastography was then validated by comparison with a poroelastic finite-element analysis (FEA). On average, the differences between the strains predicted by elastography and the FEA were within 10%. Subsequently engineered cartilage tissue was evaluated in the same test fixture. Results from these examinations showed internal regions where the local strain was 1–2 orders of magnitude greater than that near the surface. These studies document the feasibility of using ultrasound to evaluate the mechanical behaviors of maturing TE constructs in a sterile environment. PMID:26077987

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

    PubMed

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

    2017-01-21

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

  15. External Vibration Multi-directional Ultrasound Shearwave Elastography (EVMUSE): Application in Liver Fibrosis Staging

    PubMed Central

    Zhao, Heng; Song, Pengfei; Meixner, Duane D.; Kinnick, Randall R.; Callstrom, Matthew R.; Sanchez, William; Urban, Matthew W.; Manduca, Armando; Greenleaf, James F.

    2014-01-01

    Shear wave speed can be used to assess tissue elasticity, which is associated with tissue health. Ultrasound shear wave elastography techniques based on measuring the propagation speed of the shear waves induced by acoustic radiation force are becoming promising alternatives to biopsy in liver fibrosis staging. However, shear waves generated by such methods are typically very weak. Therefore, the penetration may become problematic, especially for overweight or obese patients. In this study, we developed a new method called External Vibration Multi-directional Ultrasound Shearwave Elastography (EVMUSE), in which external vibration from a loudspeaker was used to generate a multi-directional shear wave field. A directional filter was then applied to separate the complex shear wave field into several shear wave fields propagating in different directions. A two-dimensional (2D) shear wave speed map was reconstructed from each individual shear wave field, and a final 2D shear wave speed map was constructed by compounding these individual wave speed maps. The method was validated using two homogeneous phantoms and one multi-purpose tissue-mimicking phantom. Ten patients undergoing liver Magnetic Resonance Elastography (MRE) were also studied with EVMUSE to compare results between the two methods. Phantom results showed EVMUSE was able to quantify tissue elasticity accurately with good penetration. In vivo EVMUSE results were well correlated with MRE results, indicating the promise of using EVMUSE for liver fibrosis staging. PMID:25020066

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

    PubMed

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

    2015-01-01

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

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

    PubMed

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

    2015-12-01

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

  18. Ultrasound-Assisted Endoscopic Partial Plantar Fascia Release

    PubMed Central

    Ohuchi, Hiroshi; Ichikawa, Ken; Shinga, Kotaro; Hattori, Soichi; Yamada, Shin; Takahashi, Kazuhisa

    2013-01-01

    Various surgical treatment procedures for plantar fasciitis, such as open surgery, percutaneous release, and endoscopic surgery, exist. Skin trouble, nerve disturbance, infection, and persistent pain associated with prolonged recovery time are complications of open surgery. Endoscopic partial plantar fascia release offers the surgeon clear visualization of the anatomy at the surgical site. However, the primary medial portal and portal tract used for this technique have been shown to be in close proximity to the posterior tibial nerves and their branches, and there is always the risk of nerve damage by introducing the endoscope deep to the plantar fascia. By performing endoscopic partial plantar fascia release under ultrasound assistance, we could dynamically visualize the direction of the endoscope and instrument introduction, thus preventing nerve damage from inadvertent insertion deep to the fascia. Full-thickness release of the plantar fascia at the ideal position could also be confirmed under ultrasound imaging. We discuss the technique for this new procedure. PMID:24265989

  19. Elastography for the pancreas: Current status and future perspective

    PubMed Central

    Kawada, Natsuko; Tanaka, Sachiko

    2016-01-01

    Elastography for the pancreas can be performed by either ultrasound or endoscopic ultrasound (EUS). There are two types of pancreatic elastographies based on different principles, which are strain elastography and shear wave elastography. The stiffness of tissue is estimated by measuring the grade of strain generated by external pressure in the former, whereas it is estimated by measuring propagation speed of shear wave, the transverse wave, generated by acoustic radiation impulse (ARFI) in the latter. Strain elastography is difficult to perform when the probe, the pancreas and the aorta are not located in line. Accordingly, a fine elastogram can be easily obtained in the pancreatic body but not in the pancreatic head and tail. In contrast, shear wave elastography can be easily performed in the entire pancreas because ARFI can be emitted to wherever desired. However, shear wave elastography cannot be performed by EUS to date. Recently, clinical guidelines for elastography specialized in the pancreas were published from Japanese Society of Medical Ultrasonics. The guidelines show us technical knacks of performing elastography for the pancreas. PMID:27076756

  20. Elastography for the pancreas: Current status and future perspective.

    PubMed

    Kawada, Natsuko; Tanaka, Sachiko

    2016-04-14

    Elastography for the pancreas can be performed by either ultrasound or endoscopic ultrasound (EUS). There are two types of pancreatic elastographies based on different principles, which are strain elastography and shear wave elastography. The stiffness of tissue is estimated by measuring the grade of strain generated by external pressure in the former, whereas it is estimated by measuring propagation speed of shear wave, the transverse wave, generated by acoustic radiation impulse (ARFI) in the latter. Strain elastography is difficult to perform when the probe, the pancreas and the aorta are not located in line. Accordingly, a fine elastogram can be easily obtained in the pancreatic body but not in the pancreatic head and tail. In contrast, shear wave elastography can be easily performed in the entire pancreas because ARFI can be emitted to wherever desired. However, shear wave elastography cannot be performed by EUS to date. Recently, clinical guidelines for elastography specialized in the pancreas were published from Japanese Society of Medical Ultrasonics. The guidelines show us technical knacks of performing elastography for the pancreas.

  1. Detection and Measurement of Stones With Ultrasound Strain Elastography: A Phantom Study.

    PubMed

    Li, Qian; Chen, Lei; Halpern, Elkan F; Samir, Anthony E

    2015-12-01

    The sonoelastographic appearances of stones in a phantom were evaluated in this study. Ten stones were embedded into a tissue-mimicking meat phantom. The stone axial (vertical) and transverse (horizontal) dimensions measured by an electronic digital caliper, gray-scale ultrasound, and strain elastography (SE) were compared in 5 groups with stones embedded at different depths. In this study, physically measured axial and transverse stone dimensions were 1.17 to 6.86 and 1.30 to 11.15 mm, respectively. Strain elastography showed a characteristic 3-layer pattern associated with stones, comprising a superficial transition region, a hard region, and a deep transition region. As SE data were available in group 5, only data of groups 1 to 4 were analyzed. Compared with physical measurements, measurement mean errors of SE horizontal and SE vertical dimensions ranged from -0.20 to 0.42 mm and from -1.28 to -0.05 mm, respectively, in the 4 groups. Paired t testing demonstrated a significant horizontal dimension measurement error difference between B mode and SE method in group 4 (0.44 vs -0.20 mm, P < 0.05; F = 1.18, P > 0.05), but not in the other groups. Strain elastography horizontal dimension measurement error was not statistically correlated with stone size in the 4 groups. Strain elastography vertical dimension measurement error significantly correlated with stone size only in group 4 (P < 0.05). Preliminary results indicate that stone horizontal and vertical dimensions can be measured using SE in a soft tissue phantom, including when shadowing precludes measurement of vertical dimension on conventional 2-dimensional ultrasound. These results provide substantial motivation to further investigate SE as a modality to image stones in clinical practice.

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

    PubMed Central

    Slapa, Rafal Z.; Piwowonski, Antoni; Jakubowski, Wieslaw S.; Bierca, Jacek; Szopinski, Kazimierz T.; Slowinska-Srzednicka, Jadwiga; Migda, Bartosz; Mlosek, R. Krzysztof

    2012-01-01

    Although elastography can enhance the differential diagnosis of thyroid nodules, its diagnostic performance is not ideal at present. Further improvements in the technique and creation of robust diagnostic criteria are necessary. The purpose of this study was to compare the usefulness of strain elastography and a new generation of elasticity imaging called supersonic shear wave elastography (SSWE) in differential evaluation of thyroid nodules. Six thyroid nodules in 4 patients were studied. SSWE yielded 1 true-positive and 5 true-negative results. Strain elastography yielded 5 false-positive results and 1 false-negative result. A novel finding appreciated with SSWE, were punctate foci of increased stiffness corresponding to microcalcifications in 4 nodules, some not visible on B-mode ultrasound, as opposed to soft, colloid-inspissated areas visible on B-mode ultrasound in 2 nodules. This preliminary paper indicates that SSWE may outperform strain elastography in differentiation of thyroid nodules with regard to their stiffness. SSWE showed the possibility of differentiation of high echogenic foci into microcalcifications and inspissated colloid, adding a new dimension to thyroid elastography. Further multicenter large-scale studies of thyroid nodules evaluating different elastographic methods are warranted. PMID:22685685

  3. Head and neck ultrasound: technical advances, novel applications and the role of elastography.

    PubMed

    McQueen, A S; Bhatia, K S

    2017-10-03

    High-resolution ultrasound (US) provides superb anatomical detail in the superficial anatomy of the neck and has become the first-line imaging investigation for neck lumps and a crucial component of clinical pathways. In this article, a wide range of advances in neck US are described with a focus on the emerging role of ultrasound elastography. Selected examples of clinical utility are presented across a spectrum of scenarios with discussion of newer applications, service delivery, and training issues. The changing role of the neck ultrasound practitioner and the future of the technique in the head and neck are considered. Copyright © 2017 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  4. Real-time ultrasound elastography: an assessment of enlarged cervical lymph nodes.

    PubMed

    Lo, Wu-Chia; Cheng, Po-Wen; Wang, Chi-Te; Liao, Li-Jen

    2013-09-01

    To determine the efficacy of real-time elastography (RTE), compared with our previously proposed prediction model, in the detection of malignancy in cervical lymph nodes (LNs). One hundred and thirty-one patients underwent ultrasound-guided fine needle aspiration biopsy (ultrasound FNAB) after ultrasound and RTE evaluation. The formula of the RTE scoring system was a four-point visual scale, based on a previously determined model. The formula of the prediction model was: [Formula: see text]. An extended model was constructed with four previous predictors and elasticity scores, using a logistic regression model. Final histology revealed 77 benign and 54 malignant LNs. In the elasticity score system, sensitivity was 66.7 %, specificity was 57.1 %, the positive predictive value (PPV) was 52.2 % and the negative predictive value (NPV) was 71.0 %. In the prediction model system, sensitivity was 79.6 %, specificity was 92.2 %, the PPV was 87.8 % and the NPV was 86.6 %. When the extended and the original model were compared, the areas under the receiver operating characteristic curve (c-statistic) was 0.94 and 0.95, respectively (P > 0.05). Qualitative RTE offers no additional value over conventional ultrasound in predicting malignancy in cervical LNs. • An ultrasound system can help in the assessment of cervical lymph nodes. • Grey-scale and power Doppler ultrasound remain fundamental for neck nodal evaluation. • Qualitative real-time elastography provided no additional value compared with current prediction models.

  5. Ultrasound elastography assessment of bone/soft tissue interface

    NASA Astrophysics Data System (ADS)

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

    2016-01-01

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

  6. The ultrasound elastography inverse problem and the effective criteria.

    PubMed

    Aghajani, Atefeh; Haghpanahi, Mohammad; Nikazad, Touraj

    2013-11-01

    The elastography (elasticity imaging) is one of the recent state-of-the-art methods for diagnosis of abnormalities in soft tissue. The idea is based on the computation of the tissue elasticity distribution. This leads to the inverse elasticity problem; in that, displacement field and boundary conditions are known, and elasticity distribution of the tissue is aimed for computation. We treat this problem by the Gauss-Newton method. This iterative method results in an ill-posed problem, and therefore, regularization schemes are required to deal with this issue. The impacts of the initial guess for tissue elasticity distribution, contrast ratio between elastic modulus of tumor and normal tissue, and noise level of the input data on the estimated solutions are investigated via two different regularization methods. The numerical results show that the accuracy and speed of convergence vary when different regularization methods are applied. Also, the semi-convergence behavior has been observed and discussed. At the end, we signify the necessity of a clever initial guess and intelligent stopping criteria for the iterations. The main purpose here is to highlight some technical factors that have an influence on elasticity image quality and diagnostic accuracy, and we have tried our best to make this article accessible for a broad audience.

  7. Use of shear wave ultrasound elastography to quantify muscle properties in cerebral palsy.

    PubMed

    Lee, Sabrina S M; Gaebler-Spira, Deborah; Zhang, Li-Qun; Rymer, William Z; Steele, Katherine M

    2016-01-01

    Individuals with cerebral palsy tend to have altered muscle architecture and composition, but little is known about the muscle material properties, specifically stiffness. Shear wave ultrasound elastography allows shear wave speed, which is related to stiffness, to be measured in vivo in individual muscles. Our aim was to evaluate the material properties, specifically stiffness, as measured by shear wave speed of the medial gastrocnemius and tibialis anterior muscles in children with hemiplegic cerebral palsy across a range of ankle torques and positions, and fascicle strains. Shear wave speed was measured bilaterally in the medial gastrocnemius and tibialis anterior over a range of ankle positions and torques using shear wave ultrasound elastography in eight individuals with hemiplegic cerebral palsy. B-mode ultrasound was used to measure muscle thickness and fascicle strain. Shear waves traveled faster in the medial gastrocnemius and tibialis anterior of the more-affected limb by 14% (P=0.024) and 20% (P=0.03), respectively, when the ankle was at 90°. Shear wave speed in the medial gastrocnemius increased as the ankle moved from plantarflexion to dorsiflexion (less affected: r(2)=0.82, P<0.001; more-affected: r(2)=0.69, P<0.001) and as ankle torque increased (less affected: r(2)=0.56, P<0.001; more-affected: r(2)=0.45, P<0.001). In addition, shear wave speed was strongly correlated with fascicle strain (less affected: r(2)=0.63, P<0.001; more-affected: r(2)=0.53, P<0.001). The higher shear wave speed in the more-affected limb of individuals with cerebral palsy indicates greater muscle stiffness, and demonstrates the clinical potential of shear wave elastography as a non-invasive tool for investigating mechanisms of altered muscle properties and informing diagnosis and treatment. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Ultrasound elastography in the differential diagnosis of benign and malignant cervical lesions.

    PubMed

    Lu, Rong; Xiao, Ying; Liu, Minhui; Shi, Dazun

    2014-04-01

    This study aimed to evaluate the clinical value of ultrasound elastography in the differential diagnosis of benign and malignant cervical lesions and to compare the accuracy of the elasticity score and strain ratio in differentiating cervical lesions. B-mode sonography and ultrasound elastography were performed on 84 cervical lesions (40 benign and 44 malignant) in 84 patients. All of the images were obtained transvaginally. The elasticity score was determined by a 5-point scoring method. Calculation of the strain ratio was based on a comparison of the average strain measured in the lesion with the adjacent tissue of the same depth, size, and shape. The findings were compared with histopathologic results. With the use of receiver operating characteristic curves, the diagnostic value of the elasticity score and strain ratio methods was determined. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of the elasticity score in the differential diagnosis of cervical lesions were 81.8%, 85.0%, 83.3%, 85.7%, and 81.0%, respectively, whereas those of the strain ratio were 90.9%, 90.0%, 90.5%, 90.9%, and 90.0%. A strain ratio cutoff value of 4.525 was used as a standard to distinguish benign from malignant lesions. The strain ratio values of malignant lesions were much higher than those of benign lesions (range, 4.85-8.91 versus 0.62-4.50). The differences were statistically significant (P < .01). Ultrasound elastography is a promising technique that is easy and rapid to perform and can help identify cervical lesions that are likely to be malignant. It is obvious that the strain ratio yielded better results than the elasticity score. Both methods are semiquantitative, but quantification of the strain ratio is finer than that of the elasticity score.

  9. Correlation between Ultrasound Elastography and Histologic Characteristics of Papillary Thyroid Carcinoma

    PubMed Central

    Yi, Li; Qiong, Wu; Yan, Wang; Youben, Fan; Bing, Hu

    2017-01-01

    The aim of this study was to investigate the correlation between elastography and histologic characteristics including fibrosis and calcification. We also wanted to investigate whether other clinicopathologic indexes influence the strain ratio (SR) of papillary thyroid carcinomas (PTCs). We retrospectively reviewed 126 papillary thyroid carcinomas (PTCs) from 103 patients who underwent ultrasonography and elastography before surgery. The histologic characteristics and clinicopathologic indexes were compared with the SR of ultrasound elastography (UE). The results showed that there was a significantly positive correlation between fibrosis degree and SR measurements (r = 0.754, p = 0.000); the SR was significantly different between the groups with and without calcification (11.34 ± 10.08 vs. 6.81 ± 7.33, p = 0.000). The standard coefficients of collagen and stromal calcification were 0.684 and 0.194, respectively. There was no significant correlation between SR and indices such as size, position, co-existence with Hashimoto’s thyroiditis (HT), multifocality or cervical lymph node (CLN) metastasis. In conclusion, we found that the SR of UE is positively correlated with the fibrosis of PTC. Stromal calcification will elevate the SR dramatically, but psammoma bodies will not when they exist in the absence of stromal calcification. PMID:28327620

  10. Endoscopic Ultrasound-Guided Management of Bleeding Rectal Varices.

    PubMed

    Philips, Cyriac Abby; Augustine, Philip

    2017-01-01

    Rectal variceal bleeding, though rare, can pose significant morbidity and mortality in the wake of treatment failure. Conventional treatment utilizing endoscopic glue injection might not be feasible in all cases due to poor visualization and inadvertent missing of variceal source of bleed. Endoscopic ultrasound (EUS)-guided rectal variceal management is a promising and effective modality. We provide real-time images and a video of EUS-guided precision management of rectal variceal bleed using coiling and glue in a cirrhotic.

  11. Prediction of cervical lymph node metastasis in patients with papillary thyroid cancer using combined conventional ultrasound, strain elastography, and acoustic radiation force impulse (ARFI) elastography.

    PubMed

    Xu, Jun-Mei; Xu, Xiao-Hong; Xu, Hui-Xiong; Zhang, Yi-Feng; Guo, Le-Hang; Liu, Lin-Na; Liu, Chang; Bo, Xiao-Wan; Qu, Shen; Xing, Mingzhao; Li, Xiao-Long

    2016-08-01

    To investigate the value of combined conventional ultrasound (US), strain elastography (SE) and acoustic radiation force impulse (ARFI) elastography for prediction of cervical lymph node metastasis (CLNM) in papillary thyroid cancer (PTC). A consecutive series of 203 patients with 222 PTCs were preoperatively evaluated by US, SE, and ARFI including virtual touch tissue imaging (VTI) and virtual touch tissue quantification (VTQ). A multivariate analysis was performed to predict CLNM by 22 independent variables. Receiver operating characteristic (ROC) curve analysis was used to evaluate the diagnostic performance. Multivariate analysis demonstrated that VTI area ratio (VAR) > 1 was the best predictor for CLNM, followed by abnormal cervical lymph node (ACLN), capsule contact, microcalcification, capsule involvement, and multiple nodules (all P < 0.05). ROC analyses of these characteristics showed the areas under the curve (Az), sensitivity, and specificity were 0.600-0.630, 47.7 %-93.2 %, and 26.9 %-78.4 % for US, respectively; and they were 0.784, 83.0 %, and 73.9 %, respectively, for VAR > 1. As combination of US characteristics with and without VAR, the Az, sensitivity, and specificity were 0.803 and 0.556, 83.0 % and 100.0 %, and 77.6 % and 11.2 %, respectively (P < 0.001). ARFI elastography shows superior performance over conventional US, particularly when combined with US, in predicting CLNM in PTC patients. • Conventional ultrasound is useful in predicting cervical lymph node metastasis preoperatively. • Virtual touch tissue imaging area ratio is the strongest predicting factor. • Predictive performance is markedly improved by combining ultrasound characteristics with VAR. • Acoustic radiation force impulse elastography may be a promising complementary tool.

  12. Remote ultrasound palpation for robotic interventions using absolute elastography.

    PubMed

    Schneider, Caitlin; Baghani, Ali; Rohling, Robert; Salcudean, Septimiu

    2012-01-01

    Although robotic surgery has addressed many of the challenges presented by minimally invasive surgery, haptic feedback and the lack of knowledge of tissue stiffness is an unsolved problem. This paper presents a system for finding the absolute elastic properties of tissue using a freehand ultrasound scanning technique, which utilizes the da Vinci Surgical robot and a custom 2D ultrasound transducer for intraoperative use. An external exciter creates shear waves in the tissue, and a local frequency estimation method computes the shear modulus. Results are reported for both phantom and in vivo models. This system can be extended to any 6 degree-of-freedom tracking method and any 2D transducer to provide real-time absolute elastic properties of tissue.

  13. Added value of Virtual Touch IQ shear wave elastography in the ultrasound assessment of breast lesions.

    PubMed

    Ianculescu, Victor; Ciolovan, Laura Maria; Dunant, Ariane; Vielh, Philippe; Mazouni, Chafika; Delaloge, Suzette; Dromain, Clarisse; Blidaru, Alexandru; Balleyguier, Corinne

    2014-05-01

    To determine the diagnostic performance of Acoustic Radiation Force Impulse (ARFI) Virtual Touch IQ shear wave elastography in the discrimination of benign and malignant breast lesions. Conventional B-mode and elasticity imaging were used to evaluate 110 breast lesions. Elastographic assessment of breast tissue abnormalities was done using a shear wave based technique, Virtual Touch IQ (VTIQ), implemented on a Siemens Acuson S3000 ultrasound machine. Tissue mechanical properties were interpreted as two-dimensional qualitative and quantitative colour maps displaying relative shear wave velocity. Wave speed measurements in m/s were possible at operator defined regions of interest. The pathologic diagnosis was established on samples obtained by ultrasound guided core biopsy or fine needle aspiration. BIRADS based B-mode evaluation of the 48 benign and 62 malignant lesions achieved 92% sensitivity and 62.5% specificity. Subsequently performed VTIQ elastography relying on visual interpretation of the colour overlay displaying relative shear wave velocities managed similar standalone diagnostic performance with 92% sensitivity and 64.6% specificity. Lesion and surrounding tissue shear wave speed values were calculated and a significant difference was found between the benign and malignant populations (Mann-Whitney U test, p<0.0001). By selecting a lesion cut-off value of 3.31m/s we achieved 80.4% sensitivity and 73% specificity. Applying this threshold only to BIRADS 4a masses, we reached overall levels of 92% sensitivity and 72.9% specificity. VTIQ qualitative and quantitative elastography has the potential to further characterise B-mode detected breast lesions, increasing specificity and reducing the number of unnecessary biopsies. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  14. Modeling Transversely Isotropic, Viscoelastic, Incompressible Tissue-like Materials with Application in Ultrasound Shear Wave Elastography

    PubMed Central

    Qiang, Bo; Brigham, John C.; Aristizabal, Sara; Greenleaf, James F.; Zhang, Xiaoming; Urban, Matthew W.

    2015-01-01

    In this paper, we propose a method to model the shear wave propagation in transversely isotropic, viscoelastic and incompressible media. The targeted application is ultrasound-based shear wave elastography for viscoelasticity measurements in anisotropic tissues such as the kidney and skeletal muscles. The proposed model predicts that if the viscoelastic parameters both across and along fiber directions can be characterized as a Voigt material, then the spatial phase velocity at any angle is also governed by a Voigt material model. Further, with the aid of Taylor expansions, it is shown that the spatial group velocity at any angle is close to a Voigt type for weakly attenuative materials within a certain bandwidth. The model is implemented in a finite element code by a time domain explicit integration scheme and shear wave simulations are conducted. The results of the simulations are analyzed to extract the shear wave elasticity and viscosity for both the spatial phase and group velocities. The estimated values match well with theoretical predictions. The proposed theory is further verified by an ex vivo tissue experiment measured in a porcine skeletal muscle by an ultrasound shear wave elastography method. The applicability of the Taylor expansion to analyze the spatial velocities is also discussed. We demonstrate that the approximations from the Taylor expansions are subject to errors when the viscosities across or along the fiber directions are large or the maximum frequency considered is beyond the bandwidth defined by radii of convergence of the Taylor expansions. PMID:25591921

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

    PubMed

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

    2015-01-01

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

  16. Visualizing the stress distribution within vascular tissues using intravascular ultrasound elastography: a preliminary investigation.

    PubMed

    Richards, Michael S; Perucchio, Renato; Doyley, Marvin M

    2015-06-01

    A methodology for computing the stress distribution of vascular tissue using finite element-based, intravascular ultrasound (IVUS) reconstruction elastography is described. This information could help cardiologists detect life-threatening atherosclerotic plaques and predict their propensity to rupture. The calculation of vessel stresses requires the measurement of strain from the ultrasound images, a calibrating pressure measurement and additional model assumptions. In this work, we conducted simulation studies to investigate the effect of varying the model assumptions, specifically Poisson's ratio and the outer boundary conditions, on the resulting stress fields. In both simulation and phantom studies, we created vessel geometries with two fibrous cap thicknesses to determine if we could detect a difference in peak stress (spatially) between the two. The results revealed that (i) Poisson's ratios had negligible impact on the accuracy of stress elastograms, (ii) the outer boundary condition assumption had the greatest effect on the resulting modulus and stress distributions and (iii) in simulation and in phantom experiments, our stress imaging technique was able to detect an increased peak stress for the vessel geometry with the smaller cap thickness. This work is a first step toward understanding and creating a robust stress measurement technique for evaluating atherosclerotic plaques using IVUS elastography.

  17. Numerical characterization of quasi-static ultrasound elastography for the detection of deep tissue injuries.

    PubMed

    Hamaluik, Kenton; Moussa, Walied; Ferguson-Pell, Martin

    2014-07-01

    Deep tissue injuries are subcutaneous regions of tissue breakdown associated with excessive mechanical pressure for extended period of time. These wounds are currently clinically undetectable in their early stages and result in severe burdens on not only the patients who suffer from them, but the health care system as well. The goal of this work was to numerically characterize the use of quasi-static ultrasound elastography for detecting formative and progressive deep tissue injuries. In order to numerically characterize the technique, finite-element models of sonographic B-mode imaging and tissue deformation were created. These models were fed into a local strain-estimation algorithm to determine the detection sensitivity of the technique on various parameters. Our work showed that quasi-static ultrasound elastography was able to detect and characterize deep tissue injuries over a range of lesion parameters. Simulations were validated using a physical phantom model. This work represents a step along the path to developing a clinically relevant technique for detecting and diagnosing early deep tissue injuries.

  18. In Vivo Estimation of Perineal Body Properties Using Ultrasound Quasistatic Elastography in Nulliparous Women

    PubMed Central

    Chen, Luyun; Low, Lisa Kane; DeLancey, John OL; Ashton-Miller, James A

    2015-01-01

    Objective The perineal body must undergo a remarkable transformation during pregnancy to accommodate an estimated stretch ratio of over 3.3 in order to permit vaginal delivery of the fetal head. Yet measurements of perineal body elastic properties are lacking in vivo, whether in the pregnant or non-pregnant state. The objective of this study, therefore, was to develop a method for measuring perineal body elastic modulus and to test its feasibility in young nulliparous women. Methods An UltraSONIX RP500 ultrasound system was equipped with elastography software. Approximately 1 Hz free-hand sinusoidal compression loading of the perineum was used to measure the relative stiffness of the perineal body compared to that of a custom reference standoff pad with a modulus of 36.7 kPa. Measurements were made in 20 healthy nulliparous women. Four subjects were invited back for second and third visits to evaluate within- and between-visit repeatability using the coefficient of variation. Results The mean± SD elastic compression modulus of the perineal body was 28.9 ± 4.7 kPa. Within- and between-visit repeatability averaged 3.4% and 8.3%, respectively. Conclusion Ultrasound elastography using a standoff pad reference provides a valid method for evaluating the elastic modulus of the perineal body in living women. PMID:25801422

  19. Comparison of fractional wave equations for power law attenuation in ultrasound and elastography.

    PubMed

    Holm, Sverre; Näsholm, Sven Peter

    2014-04-01

    A set of wave equations with fractional loss operators in time and space are analyzed. The fractional Szabo equation, the power law wave equation and the causal fractional Laplacian wave equation are all found to be low-frequency approximations of the fractional Kelvin-Voigt wave equation and the more general fractional Zener wave equation. The latter two equations are based on fractional constitutive equations, whereas the former wave equations have been derived from the desire to model power law attenuation in applications like medical ultrasound. This has consequences for use in modeling and simulation, especially for applications that do not satisfy the low-frequency approximation, such as shear wave elastography. In such applications, the wave equations based on constitutive equations are the viable ones. Copyright © 2014 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  20. A stochastic filtering approach to recover strain images from quasi-static ultrasound elastography

    PubMed Central

    2014-01-01

    Background Model-based reconstruction algorithms have shown potentials over conventional strain-based methods in quasi-static elastographic image by using realistic finite element (FE) or bio-mechanical model constraints. However, it is still difficult to properly handle the discrepancies between the model constraint and ultrasound data, and the measurement noise. Methods In this paper, we explore the usage of Kalman filtering algorithm for the estimation of strain imaging in quasi-static ultrasound elastography. The proposed strategy formulates the displacement distribution through biomechanical models, and the ultrasound-derived measurements through observation equations. Through this filtering strategy, the discrepancies are quantitatively modelled as one Gaussian white noise, and the measurement noise of ultrasound data is modelled as another independent Gaussian white noise. The optimal estimation of kinematic functions, i.e. the full displacement and velocity field, are computed through this Kalman filter. Then the strain images can be easily calculated from the estimated displacement field. Results The accuracy and robustness of our proposed framework is first evaluated in synthetic data in controlled conditions, and the performance of this framework is then evaluated in the real data collected from elastography phantoms and patients with favourable results. Conclusions The potential of our algorithm is to provide the distribution of mechanically meaningful strain under a proper biomechanical model constraint. We address the model-data discrepancy and measurement noise by introducing process noise and measurement noise in our framework, and then the mechanically meaningful strain is estimated through the Kalman filter in the minimum mean square error (MMSE) sense. PMID:24521481

  1. Ultrasound Elastography Based on Multiscale Estimations of Regularized Displacement Fields

    PubMed Central

    Frouin, Frédérique; Insana, Michael F.; Herment, Alain

    2009-01-01

    Elasticity imaging is based on the measurements of local tissue deformation. The approach to ultrasound elasticity imaging presented in this paper relies on the estimation of dense displacement fields by a coarse-to-fine minimization of an energy function that combines constraints of conservation of echo amplitude and displacement field continuity. The multiscale optimization scheme presents several characteristics aimed at improving and accelerating the convergence of the minimization process. This includes the nonregularized initialization at the coarsest resolution and the use of adaptive configuration spaces. Parameters of the energy model and optimization were adjusted using data obtained from a tissue-like phantom material. Elasticity images from normal in vivo breast tissue were subsequently obtained with these parameters. Introducing a smoothness constraint into motion field estimation helped solve ambiguities due to incoherent motion, leading to elastograms less degraded by decorrelation noise than the ones obtained from correlation-based techniques. PMID:14964561

  2. Investigation of the acute plantar fasciitis with contrast-enhanced ultrasound and shear wave elastography - first results.

    PubMed

    Putz, Franz Josef; Hautmann, Matthias G; Banas, Miriam; Jung, Ernst Michael

    2017-09-04

    The plantar fasciitis is a common disease with a high prevalence in public and a frequent cause of heel pain. In our pilot study, we wanted to characterise the feasibility of shear-wave elastography and contrast-enhanced ultrasound (CEUS) in the assessment of the plantar fasciitis. 23 cases of painful heels were examined by B-Mode ultrasound, Power Doppler (PD), shear wave elastography and contrast-enhanced ultrasound before anti-inflammatory radiation. Time-intensity-curves were analysed by the integrated software. The results for area-under-the-curve (AUC), peak, time-to-peak (TTP) and mean-transit-time (MTT) were compared between the plantar fascia and the surrounding tissue. All cases showed thickening of the plantar fascia, in most cases with interstitial oedema (87.0%). Shear wave elastography showed inhomogeneous stiffness of the plantar fascia. 83.3% of cases showed a visible hyperperfusion in CEUS at the proximal plantar fascia in comparison to the surrounding tissue. This hyperperfusion could also be found in 75.0% of cases with no signs of vascularisation in PD. AUC (p = 0.0005) and peak (p = 0.037) were significantely higher in the plantar fascia than in the surrounding tissue. CEUS and shear wave elastography are new diagnostic tools in the assessment of plantar fasciitis and can provide quantitative parameters for monitoring therapy.

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

    PubMed Central

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

    2015-01-01

    Purpose To investigate the effects of macrocalcifications and clustered microcalcifications associated with benign breast masses on shear wave elastography (SWE). Methods SuperSonic Imagine (SSI) and comb-push ultrasound shear elastography (CUSE) were performed on three sets of phantoms to investigate how calcifications of different sizes and distributions influence measured elasticity. To demonstrate the effect in vivo, three female patients with benign breast masses associated with mammographically-identified calcifications were evaluated by CUSE. Results Apparent maximum elasticity (Emax) estimates resulting from individual macrocalcifications (with diameters of 2mm, 3mm, 5mm, 6mm, 9mm, 11mm, and 15mm) showed values over 50 kPa for all cases, which represents more than 100% increase over background (~21kPa). We considered a 2cm-diameter circular region of interest for all phantom experiments. Mean elasticity (Emean) values varied from 26 kPa to 73 kPa, depending on the macrocalcification size. Highly dense clusters of microcalcifications showed higher Emax values than clusters of microcalcification with low concentrations, but the difference in Emean values was not significant. Conclusions Our results demonstrate that the presence of large isolated macrocalcifications and highly concentrated clusters of microcalcifications can introduce areas with apparent high elasticity in SWE. Considering that benign breast masses normally have significantly lower elasticity values than malignant tumors, such areas with high elasticity appearing due to presence of calcification in benign breast masses may lead to misdiagnosis. PMID:26368939

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

    PubMed

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

    2016-05-01

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

  5. Endoscopic Ultrasound-Guided Management of Bleeding Rectal Varices

    PubMed Central

    Augustine, Philip

    2017-01-01

    Rectal variceal bleeding, though rare, can pose significant morbidity and mortality in the wake of treatment failure. Conventional treatment utilizing endoscopic glue injection might not be feasible in all cases due to poor visualization and inadvertent missing of variceal source of bleed. Endoscopic ultrasound (EUS)-guided rectal variceal management is a promising and effective modality. We provide real-time images and a video of EUS-guided precision management of rectal variceal bleed using coiling and glue in a cirrhotic. PMID:28879206

  6. Endoscopic Ultrasound-Guided Therapies in Pancreatic Neoplasms

    PubMed Central

    Yang, Dennis; DiMaio, Christopher J.

    2015-01-01

    Endoscopic ultrasound (EUS) has evolved from being primarily a diagnostic modality into an interventional endoscopic tool for the management of both benign and malignant gastrointestinal illnesses. EUS-guided therapy has garnered particular interest as a minimally invasive approach for the treatment of pancreatic cancer, a disease often complicated by its aggressive course and poor survival. The potential advantage of an EUS-guided approach revolves around real-time imaging for targeted therapy of a difficult to reach organ. In this review, we focus on EUS-guided therapies for pancreatic neoplasms. PMID:25802863

  7. Lung transthoracic ultrasound elastography imaging and guided biopsies of subpleural cancer: a preliminary report.

    PubMed

    Sperandeo, Marco; Trovato, Francesca M; Dimitri, Lucia; Catalano, Daniela; Simeone, Anna; Martines, Giuseppe Fabio; Piscitelli, Angela Pamela; Trovato, Guglielmo M

    2015-07-01

    Despite the usefulness of elastography in assessing the stiffness/elasticity of tissues, and its proven diagnostic accuracy in thyroid, breast, and prostate cancers, among others, it is not yet applied in transthoracic ultrasound (TUS) scans to investigate lung nodules. To investigate the potential clinical utility of TUS elastography in diagnosing lung cancer proven by fine-needle aspiration biopsy (FNAB). TUS elastography was performed in 95 consecutive patients (71 men, 24 women; age, 62.84 ± 7.37 years) with lesions suspected of involving the chest wall or the pleura detected on chest X-ray or computed tomography (CT). Patients with pleural effusions were not enrolled, but were further evaluated by pleural fluid cytology. Patients were excluded from the study if a diagnosis had already been made based on sputum cytology and/or bronchoscopic histology (making TUS biopsy unnecessary) or if their lung lesions could not be visualized under standard US. Under FNAB, 34 consolidations were ascribed to pneumonia and 65 to cancer. Under TUS, tissue stiffness, detected using a convex multifrequency 2-8-mHz probe and a MyLab™Twice - ElaXto, was scored from 1 (greatest elasticity) to 5 (no elasticity). Subpleural solid masses (2-5 cm) were initially detected by TUS and subsequently assessed by FNAB. Histological diagnoses were: small cell lung cancer (4/61), adenocarcinoma (29/61), squamous cell carcinoma (SCC) (12/61), large cell lung carcinoma (12/61), and lymphomas (4/61). Patients' age and mass sizes (3.06 ± 0.88 cm) were not significantly associated with any histological type. A significant lower elasticity of SCC (4.67 ± 0.492) was observed versus other types of lung cancer (P < 0.005), and versus pneumonia (2.35 ± 0.48). Since only squamous cell lung carcinoma displays the feature of significantly reduced elasticity, and since no clear-cut diagnostic key is yet available, the clinical usefulness of TUS elastography is currently limited

  8. [Differential diagnostic value of real-time tissue elastography and three dimensional ultrasound imaging in breast lumps].

    PubMed

    Li, M H; Liu, Y; Liu, L S; Li, P X; Chen, Q

    2016-05-24

    To investigate the real-time tissue elastography and 3D contrast-enhanced ultrasonography(CEUS) in breast lumps differential diagnostic value. A total of 126 patients (180 lumps) with breast mass were retrospectively analyzed from December 2012 to December 2014 in Tumor Hospital Affiliated To Xinjiang Medical University.All patients were divided into three groups by using stratified random method.Each group was detected by real-time tissue elastography, 3D CEUS and two joint inspection.Each group of 42 cases (60 lumps) was confirmed by the pathological results as gold standard.Diagnostic sensitivity, specificity and coincidence rate of different methods were compared. The benign masses of ultrasound contrast showed the punctate, linear and nodular enhancement, and the border of enhancement was smooth.The malignant tumors were mainly dominated by uneven and high enhancement. There was no statistical difference in sensitivity, specificity and coincidence rate between elastography group and 3D CEUS group (64.7% vs 73.5%, 69.2% vs 76.9%, 66.7% vs 75.0%, all P>0.05). The sensitivity, specificity and coincidence rate of two joint inspection group were higher than those of elastography group and 3D CEUS group, the differences were statistically significant (97.1%, 92.3% and 98.3% , all P<0.05). 3D CEUS combined with real-time tissue elastography is of high value in the diagnosis of breast masses.

  9. Reprint of "Update on ultrasound elastography: Miscellanea. Prostate, testicle, musculo-skeletal".

    PubMed

    Correas, J M; Drakonakis, E; Isidori, A M; Hélénon, O; Pozza, C; Cantisani, V; Di Leo, N; Maghella, F; Rubini, A; Drudi, F M; D'ambrosio, F

    2014-03-01

    Nowadays ultrasound elastosonography is an established technique, although with limited clinical application, used to assess tissue stiffness, which is a parameter that in most cases is associated with malignancy. However, although a consistent number of articles have been published about several applications of elastosonography, its use in certain human body districts is still not well defined. In this paper we write on the use of elastosonography in prostate, testicle and musculo-skeletal apparatus. We report and compare the work of several authors, different type of elastosonography (shear wave, strain elastography, etc.) and instrumental data obtained in the study of both benign and malignant lesions. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  10. Cervical strain determined by ultrasound elastography and its association with spontaneous preterm delivery

    PubMed Central

    Hernandez-Andrade, Edgar; Romero, Roberto; Korzeniewski, Steven J.; Ahn, Hyunyoung; Aurioles-Garibay, Alma; Garcia, Maynor; Schwartz, Alyse G.; Yeo, Lami; Chaiworapongsa, Tinnakorn; Hassan, Sonia S.

    2014-01-01

    Objective To determine if there is an association between cervical strain, evaluated using ultrasound elastography, and spontaneous preterm delivery (sPTD) <37 weeks of gestation. Methods One hundred and eighty nine (189) women at 16–24 weeks of gestation were evaluated. Ultrasound elastography was used to estimate cervical strain in three anatomical planes: one mid-sagittal in the same plane used for cervical length measurement, and two cross sectional images: one at the level of the internal cervical os, and the other at the level of the external cervical os. In each plane, two regions of interest (endocervix and entire cervix) were examined; a total of six regions of interest were evaluated. Results The prevalence of sPTD was 11% (21/189). Strain values from each of the six cervical regions correlated weakly with cervical length (r= −0.24, p<0.001 to r= −0.03, p=0.69). Strain measurements obtained in a cross sectional view of the internal cervical os were significantly associated with sPTD. Women with strain values ≤25th centile in the endocervical canal (0.19) and in the entire cervix (0.14) were 80% less likely to have a sPTD than women with strain values >25th centile (endocervical: odds ratio [OR] 0.2; 95% confidence interval [CI], 0.03–0.96; entire cervix: OR 0.17; 95% CI, 0.03–0.9). Additional adjustment for gestational age, race, smoking status, parity, maternal age, pre-pregnancy body mass index and previous preterm delivery did not appreciably alter the magnitude or statistical significance of these associations. Strain values obtained from the external cervical os and from the sagittal view were not associated with sPTD. Conclusion Low strain values in the internal cervical os were associated with a significantly lower risk of spontaneous preterm delivery <37 weeks of gestation. PMID:24356388

  11. Application of high-resolution ultrasound, real-time elastography, and contrast-enhanced ultrasound in differentiating solid thyroid nodules

    PubMed Central

    Zhang, Yu-Zhi; Xu, Ting; Gong, Hai-Yan; Li, Cui-Ying; Ye, Xin-Hua; Lin, Hong-Jun; Shen, Mei-Ping; Duan, Yu; Yang, Tao; Wu, Xiao-Hong

    2016-01-01

    Abstract High-resolution ultrasound (HRUS) is a sensitive tool for identifying thyroid nodules. Real-time elastography (RTE) and contrast-enhanced ultrasound (CEUS) are newly developed methods which could measure tissue elasticity and perfusion features. The aim of the present study was to evaluate and compare the diagnostic efficiency of HRUS, RTE, CEUS and their combined use in the differentiation of benign and malignant solid thyroid nodules. In total, 111 consecutive patients with 145 thyroid nodules who were scheduled for surgery were included in the study. All of them underwent HRUS, RTE, and CEUS examination. The independent ultrasound (US) predictors for malignancy were determined and quantified using logistic regression analysis, based on which a risk-scoring model was established for each method. The diagnostic efficiency of each method was assessed by receiver operating characteristic (ROC) curve analysis. HRUS showed the best diagnostic efficiency among the 3 US methods, with 74.6% sensitivity and 87.8% specificity. CEUS had higher sensitivity (85.7%), whereas RTE alone did not show much advantage. Combined use of RTE and HRUS increased the sensitivity (92.1%). The HRUS-RTE-CEUS combination could increase both the sensitivity and specificity (87.3%, 91.5%), with the best AUC (0.935) among all the methods. The overall diagnostic value of HRUS in predicting malignancy is the best among the 3 US methods. Combined use of RTE and CEUS and HRUS could improve the diagnostic efficiency for solid thyroid nodules. PMID:27828854

  12. Comparison Between Neck and Shoulder Stiffness Determined by Shear Wave Ultrasound Elastography and a Muscle Hardness Meter.

    PubMed

    Akagi, Ryota; Kusama, Saki

    2015-08-01

    The goals of this study were to compare neck and shoulder stiffness values determined by shear wave ultrasound elastography with those obtained with a muscle hardness meter and to verify the correspondence between objective and subjective stiffness in the neck and shoulder. Twenty-four young men and women participated in the study. Their neck and shoulder stiffness was determined at six sites. Before the start of the measurements, patients rated their present subjective symptoms of neck and shoulder stiffness on a 6-point verbal scale. At all measurement sites, the correlation coefficients between the values of muscle hardness indices determined by the muscle hardness meter and shear wave ultrasound elastography were not significant. Furthermore, individuals' subjective neck and shoulder stiffness did not correspond to their objective symptoms. These results suggest that the use of shear wave ultrasound elastography is essential to more precisely assess neck and shoulder stiffness. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  13. Ultrasound elastography in diagnosis and follow-up for patients with chronic recurrent parotitis.

    PubMed

    Zengel, Pamela; Reichel, Christoph A; Vincek, Teresa; Clevert, Dirk André

    2017-09-04

    Chronic recurrent parotitis (CRP) is a non-obstructive disease with episodes characterized by painful swelling of the parotid gland. It presents in both a juvenile and an adult form, with no clear information on its actual origin. Diagnosis is based on patient medical history and ultrasound examination but is frequently not correctly identified. Acoustic Radiation Force Impulse Imaging (ARFI) is a novel ultrasound elastography technology that has recently been implemented in the diagnostic work-up of patients with malignancies. This study aimed to answer whether ARFI can reasonably be employed in the initial examination and follow-up during therapy in patients with CRP. Mechanical tissue properties of the salivary glands were analyzed by ARFI in 37 parotid glands of patients with CRP. Having integrated ARFI into our diagnostic protocol for CRP, affected parotid glands were found to exhibit lower tissue elasticity compared to both healthy contralateral glands in the same individuals as well as those of healthy individuals. Most importantly, this method enabled us to quantitatively assess the patient benefit of therapy regarding the recovery of the glands' diseased parenchyma. ARFI provides a quick, easy, and reliable diagnostic tool for the assessment of disease severity and progression in patients with CRP that can be seamlessly implemented into preexisting ultrasound protocols.

  14. Microscale characterization of the viscoelastic properties of hydrogel biomaterials using dual-mode ultrasound elastography.

    PubMed

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

    2016-05-01

    Characterization of the microscale mechanical properties of biomaterials is a key challenge in the field of mechanobiology. Dual-mode ultrasound elastography (DUE) uses high frequency focused ultrasound to induce compression in a sample, combined with interleaved ultrasound imaging to measure the resulting deformation. This technique can be used to non-invasively perform creep testing on hydrogel biomaterials to characterize their viscoelastic properties. DUE was applied to a range of hydrogel constructs consisting of either hydroxyapatite (HA)-doped agarose, HA-collagen, HA-fibrin, or preosteoblast-seeded collagen constructs. DUE provided spatial and temporal mapping of local and bulk displacements and strains at high resolution. Hydrogel materials exhibited characteristic creep behavior, and the maximum strain and residual strain were both material- and concentration-dependent. Burger's viscoelastic model was used to extract characteristic parameters describing material behavior. Increased protein concentration resulted in greater stiffness and viscosity, but did not affect the viscoelastic time constant of acellular constructs. Collagen constructs exhibited significantly higher modulus and viscosity than fibrin constructs. Cell-seeded collagen constructs became stiffer with altered mechanical behavior as they developed over time. Importantly, DUE also provides insight into the spatial variation of viscoelastic properties at sub-millimeter resolution, allowing interrogation of the interior of constructs. DUE presents a novel technique for non-invasively characterizing hydrogel materials at the microscale, and therefore may have unique utility in the study of mechanobiology and the characterization of hydrogel biomaterials.

  15. Automated 3D ultrasound elastography of the breast: a phantom validation study

    NASA Astrophysics Data System (ADS)

    Hendriks, Gijs A. G. M.; Holländer, Branislav; Menssen, Jan; Milkowski, Andy; Hansen, Hendrik H. G.; de Korte, Chris L.

    2016-04-01

    In breast cancer screening, the automated breast volume scanner (ABVS) was introduced as an alternative for mammography since the latter technique is less suitable for women with dense breasts. Although clinical studies show promising results, clinicians report two disadvantages: long acquisition times (>90 s) introducing breathing artefacts, and high recall rates due to detection of many small lesions of uncertain malignant potential. Technical improvements for faster image acquisition and better discrimination between benign and malignant lesions are thus required. Therefore, the aim of this study was to investigate if 3D ultrasound elastography using plane-wave imaging is feasible. Strain images of a breast elastography phantom were acquired by an ABVS-mimicking device that allowed axial and elevational movement of the attached transducer. Pre- and post-deformation volumes were acquired with different constant speeds (between 1.25 and 40.0 mm s-1) and by three protocols: Go-Go (pre- and post-volumes with identical start and end positions), Go-Return (similar to Go-Go with opposite scanning directions) and Control (pre- and post-volumes acquired per position, this protocol can be seen as reference). Afterwards, 2D and 3D cross-correlation and strain algorithms were applied to the acquired volumes and the results were compared. The Go-Go protocol was shown to be superior with better strain image quality (CNRe and SNRe) than Go-Return and to be similar as Control. This can be attributed to applying opposite mechanical forces to the phantom during the Go-Return protocol, leading to out-of-plane motion. This motion was partly compensated by using 3D cross-correlation. However, the quality was still inferior to Go-Go. Since these results were obtained in a phantom study with controlled deformations, the effect of possible uncontrolled in vivo tissue motion artefacts has to be addressed in future studies. In conclusion, it seems feasible to implement 3D ultrasound

  16. Utility of endoscopic ultrasound in pancreatitis: A review

    PubMed Central

    Rizk, Maged K; Gerke, Henning

    2007-01-01

    The close proximity of the endoscopic ultrasound probe to the pancreas results in superior spatial resolution compared to CT scan and MRI. In addition, endoscopic ultrasound (EUS) is a minimally invasive procedure that does not share the relatively high complication rate of ERCP. Due to these advantages, EUS has evolved into an important technique to assess pancreatobiliary disease. This review will discuss the role of EUS in patients with pancreatitis. The indications can be divided into acute pancreatitis and chronic pancreatitis. In acute pancreatitis, EUS is used to determine the etiology; in suspected chronic pancreatitis it is helpful to establish the diagnosis. Lastly, this review will discuss biliary pancreatitis with suspicion for persistent choledocholithiasis. PMID:18081219

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

    PubMed

    Fromageau, Jérémie; Lerouge, Sophie; Maurice, Roch Listz; Soulez, Gilles; Cloutier, Guy

    2008-11-21

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

  18. Endoscopic ultrasound for chronic abdominal pain and gallbladder disease.

    PubMed

    Dill, B; Dill, J E; Berkhouse, L; Palmer, S T

    1999-01-01

    Endoscopic ultrasound (EUS) is a major advance in gastrointestinal endoscopy. EUS, which is invaluable in the diagnosis and staging of gastrointestinal cancer, is now being used in the diagnosis of chronic upper abdominal pain. EUS combined with stimulated biliary drainage (EUS/SBD) aids in the diagnosis of choledocholithiasis, cholecystitis, microlithiasis, and various conditions of the upper gastrointestinal tract. This article describes the EUS/SBD procedure and nursing care. Two case histories illustrating potential benefits to patients are presented.

  19. Endoscopic ultrasound guided vascular access and therapy: A promising indication

    PubMed Central

    Vazquez-Sequeiros, Enrique; Olcina, Jose Ramon Foruny

    2010-01-01

    Endoscopic ultrasound (EUS) is an imaging technique that has consolidated its role as an important tool for diagnosis and therapeutics. In recent years we have seen a dramatic increase in the number of EUS-guided therapeutic indications (celiac plexus neurolysis/block, pseudocyst drainage, etc). Preliminary reports have suggested EUS may also be used to guide vascular access for both imaging and treating different vascular diseases. This review aims to objectively describe the existing evidence in the field. PMID:21160933

  20. Location of recurrent asymptomatic ovarian cancer through endoscopic ultrasound.

    PubMed

    Carvalho, Joaquim; Formighieri, Beatriz; Filippi, Sheila; Rossini, Lucio

    2015-01-01

    Ovarian cancer is frequent and recurrence happens in about 75% of patients. As it presents high rates of relapse, the exams for this diagnosis are widely discussed. Beside this, there have been discussions about benefits for early anatomic diagnosis and whether endoscopic ultrasound (EUS) can be used to track the relapse of the disease. We present a case, in which anatomic location and histological definition of an asymptomatic recurrence of the ovarian cancer was misdiagnosed with conventional methods, but was possible through EUS.

  1. Comparison of shear wave velocities on ultrasound elastography between different machines, transducers, and acquisition depths: a phantom study.

    PubMed

    Shin, Hyun Joo; Kim, Myung-Joon; Kim, Ha Yan; Roh, Yun Ho; Lee, Mi-Jung

    2016-10-01

    To investigate consistency in shear wave velocities (SWVs) on ultrasound elastography using different machines, transducers and acquisition depths. The SWVs were measured using an elasticity phantom with a Young's modulus of 16.9 kPa, with three recently introduced ultrasound elastography machines (A, B and C from different vendors) and two transducers (low and high frequencies) at four depths (2, 3, 4 and 5 cm). Mean SWVs from 15 measurements and coefficient of variations (CVs) were compared between three machines, two transducers and four acquisition depths. The SWVs using the high frequency transducer were not acquired at 5 cm depth in machine B, and a high frequency transducer was not available in machine C. The mean SWVs in the three machines were different (p ≤ 0.002). The CVs were 0-0.09 in three machines. The mean SWVs between the two transducers were different (p < 0.001) except at 4 and 5 cm depths in machine A. The SWVs were affected by the acquisition depths in all conditions (p < 0.001). There is considerable difference in SWVs on ultrasound elastography depending on different machines, transducers and acquisition depths. Caution is needed when using the cutoff values of SWVs in different conditions. • The shear wave velocities (SWVs) are different between different ultrasound elastography machines • The SWVs are also different between different transducers and acquisition depths • Caution is needed when using the cutoff SWVs measured under different conditions.

  2. Endoscopic ultrasound-guided drainage of pancreatic fluid collections.

    PubMed

    Fabbri, Carlo; Luigiano, Carmelo; Maimone, Antonella; Polifemo, Anna Maria; Tarantino, Ilaria; Cennamo, Vincenzo

    2012-11-16

    Pancreatic fluid collections (PFCs) develop secondary to either fluid leakage or liquefaction of pancreatic necrosis following acute pancreatitis, chronic pancreatitis, surgery or abdominal trauma. Pancreatic fluid collections include acute fluid collections, acute and chronic pancreatic pseudocysts, pancreatic abscesses and pancreatic necrosis. Before the introduction of linear endoscopic ultrasound (EUS) in the 1990s and the subsequent development of endoscopic ultrasound-guided drainage (EUS-GD) procedures, the available options for drainage in symptomatic PFCs included surgical drainage, percutaneous drainage using radiological guidance and conventional endoscopic transmural drainage. In recent years, it has gradually been recognized that, due to its lower morbidity rate compared to the surgical and percutaneous approaches, endoscopic treatment may be the preferred first-line approach for managing symptomatic PFCs. Endoscopic ultrasound-guided drainage has the following advantages, when compared to other alternatives such as surgical, percutaneous and non-EUS-guided endoscopic drainage. EUS-GD is less invasive than surgery and therefore does not require general anesthesia. The morbidity rate is lower, recovery is faster and the costs are lower. EUS-GD can avoid local complications related to percutaneous drainage. Because the endoscope is placed adjacent to the fluid collection, it can have direct access to the fluid cavity, unlike percutaneous drainage which traverses the abdominal wall. Complications such as bleeding, inadvertent puncture of adjacent viscera, secondary infection and prolonged periods of drainage with resultant pancreatico-cutaneous fistulae may be avoided. The only difference between EUS and non-EUS drainage is the initial step, namely, gaining access to the pancreatic fluid collection. All the subsequent steps are similar, i.e., insertion of guide-wires with fluoroscopic guidance, balloon dilatation of the cystogastrostomy and insertion of

  3. WFUMB guidelines and recommendations for clinical use of ultrasound elastography: Part 1: basic principles and terminology.

    PubMed

    Shiina, Tsuyoshi; Nightingale, Kathryn R; Palmeri, Mark L; Hall, Timothy J; Bamber, Jeffrey C; Barr, Richard G; Castera, Laurent; Choi, Byung Ihn; Chou, Yi-Hong; Cosgrove, David; Dietrich, Christoph F; Ding, Hong; Amy, Dominique; Farrokh, Andre; Ferraioli, Giovanna; Filice, Carlo; Friedrich-Rust, Mireen; Nakashima, Kazutaka; Schafer, Fritz; Sporea, Ioan; Suzuki, Shinichi; Wilson, Stephanie; Kudo, Masatoshi

    2015-05-01

    Conventional diagnostic ultrasound images of the anatomy (as opposed to blood flow) reveal differences in the acoustic properties of soft tissues (mainly echogenicity but also, to some extent, attenuation), whereas ultrasound-based elasticity images are able to reveal the differences in the elastic properties of soft tissues (e.g., elasticity and viscosity). The benefit of elasticity imaging lies in the fact that many soft tissues can share similar ultrasonic echogenicities but may have different mechanical properties that can be used to clearly visualize normal anatomy and delineate pathologic lesions. Typically, all elasticity measurement and imaging methods introduce a mechanical excitation and monitor the resulting tissue response. Some of the most widely available commercial elasticity imaging methods are 'quasi-static' and use external tissue compression to generate images of the resulting tissue strain (or deformation). In addition, many manufacturers now provide shear wave imaging and measurement methods, which deliver stiffness images based upon the shear wave propagation speed. The goal of this review is to describe the fundamental physics and the associated terminology underlying these technologies. We have included a questions and answers section, an extensive appendix, and a glossary of terms in this manuscript. We have also endeavored to ensure that the terminology and descriptions, although not identical, are broadly compatible across the WFUMB and EFSUMB sets of guidelines on elastography (Bamber et al. 2013; Cosgrove et al. 2013).

  4. Ultrasound dynamic micro-elastography applied to the viscoelastic characterization of soft tissues and arterial walls.

    PubMed

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

    2010-09-01

    Quantitative noninvasive methods that provide in vivo assessment of mechanical characterization of living tissues, organs and artery walls are of interest because information on their viscoelastic properties in the presence of disease can affect diagnosis and treatment options. This article proposes the dynamic micro-elastography (DME) method to characterize viscoelasticity of small homogeneous soft tissues, as well as the adaptation of the method for vascular applications [vascular dynamic micro-elastography (VDME)]. The technique is based on the generation of relatively high-frequency (240-1100 Hz) monochromatic or transient plane shear waves within the medium and the tracking of these waves from radio-frequency (RF) echoes acquired at 25 MHz with an ultrasound biomicroscope (Vevo 770, Visualsonics). By employing a dedicated shear wave gated strategy during signal acquisition, postprocessed RF sequences could achieve a very high frame rate (16,000 images per s). The proposed technique successfully reconstructed shear wave displacement maps at very high axial (60 mum) and lateral (250 mum) spatial resolutions for motions as low as a few mum. An inverse problem formulated as a least-square minimization, involving analytical simulations (for homogenous and vascular geometries) and experimental measurements were performed to retrieve storage (G') and loss (G'') moduli as a function of the shearing frequency. Viscoelasticity measurements of agar-gelatin materials and of a small rat liver were proven feasible. Results on a very thin wall (3 mm thickness) mimicking artery enabled to validate the feasibility and the reliability of the vascular inverse problem formulation. Subsequently, the G' and G'' of a porcine aorta showed that both parameters are strongly dependent on frequency, suggesting that the vascular wall is mechanically governed by complex viscoelastic laws.

  5. TSI ultrasound elastography for the diagnosis of chronic allograft nephropathy in kidney transplanted patients

    PubMed Central

    Slowinski, Torsten; Thomas, Anke; Filimonow, Sergej; Fischer, Thomas

    2013-01-01

    Purpose To answer the question whether the TSI (tissue strain imaging) sonoelastography technique can contribute to the diagnosis of chronic renal allograft damage. Material and methods A prospective study of 112 patients between June 2010 and April 2011 was conducted to compare elastography data with biopsy results and laboratory parameters in order to determine whether any correlations exist. Elastography parameters were acquired with a high-end ultrasound system and analyzed using the semiquantitative strain ratio. For comparison, patients were divided into three groups based on biopsy findings (Banff classification): group A: biopsy not necessary; group B: Banff grade I; group C: Banff grades II and III. Correlations were assessed by means of correlation (Pearson) and regression analysis. Differences between ordinal groups were tested for statistical significance by the Mann-Whitney U test. Results Mean patient age was 54.2 ± 15.01 years. Fifty-nine percent of the patients were male. The calculated TSI strain ratio of groups A and C differed significantly (p = 0.024). Groups B and C (p = 0.056) and groups A and B (p = 0.88) showed no significant difference. The TSI strain ratio did not correlate with glomerular filtration rate (r = 0.105) or creatinine (r = 0.092). Conclusion The TSI sonoelastography technique can contribute to the differentiation of different stages of renal graft damage (according to Banff classification). However, significant results were not observed for all investigated features. The TSI technique should be further evaluated in future studies including larger numbers of patients. PMID:26674928

  6. Quantification of pancreatic stiffness on intraoperative ultrasound elastography and evaluation of its relationship with postoperative pancreatic fistula.

    PubMed

    Hatano, Masahide; Watanabe, Jota; Kushihata, Fumiki; Tohyama, Taiji; Kuroda, Taira; Koizumi, Mitsuhito; Kumagi, Teru; Hisano, Yoshiko; Sugita, Atsuro; Takada, Yasutsugu

    2015-03-01

    "Soft pancreas" has often been reported as a predictive factor for postoperative pancreatic fistula (POPF) after pancreatectomy. However, pancreatic stiffness is judged subjectively by surgeons, without objective criteria. In the present study, pancreatic stiffness was quantified using intraoperative ultrasound elastography, and its relevance to POPF and histopathology was investigated. Forty-one patients (pancreatoduodenectomy, 30; distal pancreatectomy, 11) who underwent intraoperative elastography during pancreatectomy were included. The elastic ratio was determined at the pancreatic resection site (just above the portal vein) and at the remnant pancreas (head or tail). Correlations between the incidence of POPF and patient characteristics, operative variables, and the elastic ratio were examined. In addition, the relationship between the elastic ratio and the percentage of the exocrine gland at the resection stump was investigated. For pancreatoduodenectomy patients, main pancreatic duct diameter < 3.2 mm and elastic ratio < 2.09 were significant risk factors for POPF. In addition, the elastic ratio, but not main pancreatic duct diameter, was significantly associated with the percentage of exocrine gland area at the pancreatic resection stump. Pancreatic stiffness can be quantified using intraoperative elastography. Elastography can be used to diagnose "soft pancreas" and may thus be useful in predicting the occurrence of POPF.

  7. Sphincter lesions observed on ultrasound after transanal endoscopic surgery

    PubMed Central

    Mora López, Laura; Serra-Aracil, Xavier; Navarro Soto, Salvador

    2015-01-01

    AIM: To assess the morphological impact of transanal endoscopic surgery on the sphincter apparatus using the modified Starck classification. METHODS: A prospective, observational study of 118 consecutive patients undergoing Transanal Endoscopic Operation/Transanal Endoscopic Microsurgery (TEO/TEM) from March 2013 to May 2014 was performed. All the patients underwent an endoanal ultrasound prior to surgery and one and four months postoperatively in order to measure sphincter width, identify sphincter defects and to quantify them in terms of the level, depth and size of the affected anal canal. To assess the lesions, we used the “modified” Starck classification, which incorporates the variable “sphincter fragmentation”. The results were correlated with the Wexner incontinence questionnaire. RESULTS: Of the 118 patients, twelve (sphincter lesions) were excluded. The results of the 106 patients were as follows after one month: 31 (29.2%) lesions found on ultrasound after one month, median overall Starck score of 4 (range 3-6); 10 (9.4%) defects in the internal anal sphincter (IAS) and 3 (2.8%) in the external anal sphincter (EAS); 17 patients (16%) had fragmentation of the sphincter apparatus with both sphincters affected in one case. At four months: 7 (6.6%) defects, all in the IAS, overall median Starck score of 4 (range 3-6). Mean IAS widths were 3.5 mm (SD 1.14) preoperatively, 4.38 mm (SD 2.1) one month postoperatively and 4.03 mm (SD 1.46) four months postoperatively. The only statistically significant difference in sphincter width in the IAS measurements was between preoperatively and one month postoperatively. No incontinence was reported, even in cases of ultrasound abnormalities. CONCLUSION: TEO/TEM may produce ultrasound abnormalities but this is not accompanied by clinical changes in continence. The modified Starck classification is useful for describing and managing these disorders. PMID:26674666

  8. [Transabdominal ultrasound examination, contrast-enhanced ultrasound examination and endoscopic ultrasound scanning in the determination of the aetiology and the degree of severity in acute pancreatitis].

    PubMed

    Møller Andersen, Anders; Malmstrøm, Marie Louise; Novovic, Srdan; Jørgensen, Lars Nannestad; Nissen, Flemming Helge; Hansen, Mark Berner

    2013-05-20

    A transabdominal ultrasound examination is part of the standard work-up for patients with acute pancreatitis. Transabdominal ultrasound examination displays a high sensitivity for the detection of gallbladder stones. With the recent introduction of contrast enhancement in ultrasound it has become possible to determine the severity of acute pancreatitis. Endoscopic ultrasound has shown a high sensitivity in the diagnosis of stones in the common bile duct and is an important peroperative surgical tool in endoscopic transgastric necrosectomi as well.

  9. A coupled subsample displacement estimation method for ultrasound-based strain elastography

    NASA Astrophysics Data System (ADS)

    Jiang, Jingfeng; Hall, Timothy J.

    2015-11-01

    Obtaining accurate displacement estimates along both axial (parallel to the acoustic beam) and lateral (perpendicular to the beam) directions is an important task for several clinical applications such as shear strain imaging, modulus reconstruction and temperature imaging, where a full description of the two or three-dimensional (2D/3D) deformation field is required. In this study we propose an improved speckle tracking algorithm where axial and lateral motion estimations are simultaneously performed to enhance motion tracking accuracy. More specifically, using conventional ultrasound echo data, this algorithm first finds an iso-contour in the vicinity of the peak correlation between two segments of the pre- and post-deformation ultrasound radiofrequency echo data. The algorithm then attempts to find the center of the iso-contour of the correlation function that corresponds to the unknown (sub-sample) motion vector between these two segments of echo data. This algorithm has been tested using computer-simulated data, studies with a tissue-mimicking phantom, and in vivo breast lesion data. Computer simulation results show that the method improves the accuracy of both lateral and axial tracking. Such improvements are more significant when the deformation is small or along the lateral direction. Results from the tissue-mimicking phantom study are consistent with findings observed in computer simulations. Using in vivo breast lesion data we found that, compared to the 2D quadratic subsample displacement estimation methods, higher quality axial strain and shear strain images (e.g. 18.6% improvement in contrast-to-noise ratio for shear strain images) can be obtained for large deformations (up to 5% frame-to-frame and 15% local strains) in a multi-compression technique. Our initial results demonstrated that this conceptually and computationally simple method could improve the image quality of ultrasound-based strain elastography with current clinical equipment.

  10. A Coupled Subsample Displacement Estimation Method for Ultrasound-Based Strain Elastography

    PubMed Central

    Jiang, Jingfeng; Hall, Timothy J.

    2015-01-01

    Obtaining accurate displacement estimates along both axial (parallel to the acoustic beam) and lateral (perpendicular to the beam) directions is an important task for several clinical applications such as shear strain imaging, modulus reconstruction and temperature imaging, where a full description of the two or three dimensional (2D/3D) deformation field is required. In this study we propose an improved speckle tracking algorithm where axial and lateral motion estimations are simultaneously performed to enhance motion tracking accuracy. More specifically, using conventional ultrasound echo data, this algorithm first finds an iso-contour in the vicinity of the peak correlation between two segments of the pre- and post-deformation ultrasound radiofrequency echo data. The algorithm then attempts to find the center of the iso-contour of the correlation function that corresponds to the unknown (sub-sample) motion vector between these two segments of echo data. This algorithm has been tested using computer-simulated data, studies with a tissue-mimicking phantom, and in vivo breast lesion data. Computer simulation results show that the method improves the accuracy of both lateral and axial tracking. Such improvements are more significant when the deformation is small or along the lateral direction. Results from the tissue-mimicking phantom study are consistent with findings observed in computer simulations. Using in vivo breast lesion data we found that, compared to the 2D quadratic subsample displacement estimation methods, higher quality axial strain and shear strain images (e.g. 18.6% improvement in contrast-to-noise ratio for shear strain images) can be obtained for large deformations (up to 5% frame-to-frame and 15% local strains) in a multi-compression technique. Our initial results demonstrated that this conceptually and computationally simple method could improve the image quality of ultrasound-based strain elastography (SE) with current clinical equipment. PMID

  11. A coupled subsample displacement estimation method for ultrasound-based strain elastography.

    PubMed

    Jiang, Jingfeng; Hall, Timothy J

    2015-11-07

    Obtaining accurate displacement estimates along both axial (parallel to the acoustic beam) and lateral (perpendicular to the beam) directions is an important task for several clinical applications such as shear strain imaging, modulus reconstruction and temperature imaging, where a full description of the two or three-dimensional (2D/3D) deformation field is required. In this study we propose an improved speckle tracking algorithm where axial and lateral motion estimations are simultaneously performed to enhance motion tracking accuracy. More specifically, using conventional ultrasound echo data, this algorithm first finds an iso-contour in the vicinity of the peak correlation between two segments of the pre- and post-deformation ultrasound radiofrequency echo data. The algorithm then attempts to find the center of the iso-contour of the correlation function that corresponds to the unknown (sub-sample) motion vector between these two segments of echo data. This algorithm has been tested using computer-simulated data, studies with a tissue-mimicking phantom, and in vivo breast lesion data. Computer simulation results show that the method improves the accuracy of both lateral and axial tracking. Such improvements are more significant when the deformation is small or along the lateral direction. Results from the tissue-mimicking phantom study are consistent with findings observed in computer simulations. Using in vivo breast lesion data we found that, compared to the 2D quadratic subsample displacement estimation methods, higher quality axial strain and shear strain images (e.g. 18.6% improvement in contrast-to-noise ratio for shear strain images) can be obtained for large deformations (up to 5% frame-to-frame and 15% local strains) in a multi-compression technique. Our initial results demonstrated that this conceptually and computationally simple method could improve the image quality of ultrasound-based strain elastography with current clinical equipment.

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

    PubMed Central

    Jain, Deepanshu; Thosani, Nirav; Singhal, Shashideep

    2016-01-01

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

  13. Endoscopic Ultrasound-Guided Pancreatobiliary Endoscopy in Surgically Altered Anatomy

    PubMed Central

    Jirapinyo, Pichamol; Lee, Linda S.

    2016-01-01

    Endoscopic retrograde cholangiopancreatography (ERCP) has become the mainstay of therapy for pancreatobiliary diseases. While ERCP is safe and highly effective in the general population, the procedure remains challenging or impossible in patients with surgically altered anatomy (SAA). Endoscopic ultrasound (EUS) allows transmural access to the bile or pancreatic duct (PD) prior to ductal drainage using ERCP-based techniques. Also known as endosonography-guided cholangiopancreatography (ESCP), the procedure provides multiple advantages over overtube-assisted enteroscopy ERCP or percutaneous or surgical approaches. However, the procedure should only be performed by endoscopists experienced in both EUS and ERCP and with the proper tools. In this review, various EUS-guided diagnostic and therapeutic drainage techniques in patients with SAA are examined. Detailed step-by-step procedural descriptions, technical tips, feasibility, and safety data are also discussed. PMID:27894187

  14. Endoscopic ultrasound guided vascular access and therapy (with videos)

    PubMed Central

    Saxena, Payal; Lakhtakia, Sundeep

    2015-01-01

    The continued need to develop minimally invasive alternatives to surgical and radiologic interventions has driven the development of endoscopic ultrasound (EUS)-guided treatments. EUS has now stepped into the therapeutic arena. EUS provides the unique advantage of both real-time imaging and access to structures within and adjacent to the gastrointestinal (GI) tract. Hence, EUS-guided therapeutic techniques continue to evolve in several directions enabling a variety of minimally invasive therapies for pancreatic and biliary pathologies. Furthermore, the close proximity of the GI tract to vascular structures in the mediastinum and abdomen permits EUS-guided vascular access and therapy. Studies have demonstrated several EUS-guided vascular interventions by using standard endoscopic accessories and available tools from the interventional radiology armamentarium. This article provides an overview of the literature including clinical and nonclinical studies for the management of nonvariceal and variceal GI bleeding, formation of intrahepatic portosystemic shunts (IPSS), and EUS-guided cardiac access and therapy. PMID:26374574

  15. Monitoring of high-intensity focused ultrasound treatment by shear wave elastography induced by two-dimensional-array therapeutic transducer

    NASA Astrophysics Data System (ADS)

    Iwasaki, Ryosuke; Takagi, Ryo; Nagaoka, Ryo; Jimbo, Hayato; Yoshizawa, Shin; Saijo, Yoshifumi; Umemura, Shin-ichiro

    2016-07-01

    Shear wave elastography (SWE) is expected to be a noninvasive monitoring method of high-intensity focused ultrasound (HIFU) treatment. However, conventional SWE techniques encounter difficulty in inducing shear waves with adequate displacements in deep tissue. To observe tissue coagulation at the HIFU focal depth via SWE, in this study, we propose using a two-dimensional-array therapeutic transducer for not only HIFU exposure but also creating shear sources. The results show that the reconstructed shear wave velocity maps detected the coagulated regions as the area of increased propagation velocity even in deep tissue. This suggests that “HIFU-push” shear elastography is a promising solution for the purpose of coagulation monitoring in deep tissue, because push beams irradiated by the HIFU transducer can naturally reach as deep as the tissue to be coagulated by the same transducer.

  16. Endoscopic Ultrasound-Guided Oncologic Therapy for Pancreatic Cancer

    PubMed Central

    Suzuki, Rei; Irisawa, Atsushi; Bhutani, Manoop S.

    2013-01-01

    Since the development of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) in the early 1990s, its application has been extended to various diseases. For pancreatic cancer, EUS-FNA can obtain specimens from the tumor itself with fewer complications than other methods. Interventional EUS enables various therapeutic options: local ablation, brachytherapy, placement of fiducial markers for radiotherapy, and direct injection of antitumor agents into cancer. This paper will focus on EUS-guided oncologic therapy for pancreatic cancer. PMID:23533319

  17. Endoscopic ultrasound in pancreatic cancer: innovative applications beyond the basics

    PubMed Central

    Yoo, Joseph; Kistler, C. Andrew; Yan, Linda; Dargan, Andrew

    2016-01-01

    Endoscopic ultrasound (EUS) has become a mainstay in assisting in the diagnosis and staging of pancreatic cancer. In addition, EUS provides a modality to treat chronic pain through celiac plexus neurolysis. Currently, there is growing data and utilization of EUS in more diverse and innovative applications aimed at providing more sophisticated diagnostic, prognostic and therapeutic options for patients with pancreatic cancer. EUS delivery of chemotherapy, viral and biological vectors and fiducial markers may eventually revolutionize the way clinicians approach the care of a patient with pancreatic cancer. PMID:28078128

  18. Dynamic contrast-enhanced endoscopic ultrasound: A quantification method

    PubMed Central

    Dietrich, Christoph F.; Dong, Yi; Froehlich, Eckhart; Hocke, Michael

    2017-01-01

    Dynamic contrast-enhanced ultrasound (DCE-US) has been recently standardized by guidelines and recommendations. The European Federation of Societies for US in Medicine and Biology position paper describes the use for DCE-US. Comparatively, little is known about the use of contrast-enhanced endoscopic US (CE-EUS). This current paper reviews and discusses the clinical use of CE-EUS and DCE-US. The most important clinical use of DCE-US is the prediction of tumor response to new drugs against vascular angioneogenesis. PMID:28218195

  19. Endoscopic ultrasound in the diagnosis and management of carcinoma pancreas

    PubMed Central

    Puri, Rajesh; Manrai, Manish; Thandassery, Ragesh Babu; Alfadda, Abdulrahman A

    2016-01-01

    Endoscopic ultrasound (EUS) has become an important component in the diagnosis and treatment of carcinoma pancreas. With the advent of advanced imaging techniques and tissue acquisition methods the role of EUS is becoming increasingly important. Small pancreatic tumors can be reliably diagnosed with EUS. EUS guided fine needle aspiration establishes diagnosis in some cases. EUS plays an important role in staging of carcinoma pancreas and in some important therapeutic methods that include celiac plexus neurolysis, EUS guided biliary drainage and drug delivery. In this review we attempt to review the role of EUS in diagnosis and management of carcinoma pancreas. PMID:26839647

  20. Endoscopic ultrasound in the diagnosis and management of carcinoma pancreas.

    PubMed

    Puri, Rajesh; Manrai, Manish; Thandassery, Ragesh Babu; Alfadda, Abdulrahman A

    2016-01-25

    Endoscopic ultrasound (EUS) has become an important component in the diagnosis and treatment of carcinoma pancreas. With the advent of advanced imaging techniques and tissue acquisition methods the role of EUS is becoming increasingly important. Small pancreatic tumors can be reliably diagnosed with EUS. EUS guided fine needle aspiration establishes diagnosis in some cases. EUS plays an important role in staging of carcinoma pancreas and in some important therapeutic methods that include celiac plexus neurolysis, EUS guided biliary drainage and drug delivery. In this review we attempt to review the role of EUS in diagnosis and management of carcinoma pancreas.

  1. Location of recurrent asymptomatic ovarian cancer through endoscopic ultrasound

    PubMed Central

    Carvalho, Joaquim; Formighieri, Beatriz; Filippi, Sheila; Rossini, Lucio

    2015-01-01

    Ovarian cancer is frequent and recurrence happens in about 75% of patients. As it presents high rates of relapse, the exams for this diagnosis are widely discussed. Beside this, there have been discussions about benefits for early anatomic diagnosis and whether endoscopic ultrasound (EUS) can be used to track the relapse of the disease. We present a case, in which anatomic location and histological definition of an asymptomatic recurrence of the ovarian cancer was misdiagnosed with conventional methods, but was possible through EUS. PMID:25789287

  2. [Digital scanning converter for medical endoscopic ultrasound imaging].

    PubMed

    Chen, Xiaodong; Zhang, Hongxu; Zhou, Peifan; Wen, Shijie; Yu, Daoyin

    2009-02-01

    This paper mainly introduces the design of digital scanning converter (DSC) for medical endoscopic ultrasound imaging. Fast modified vector totational CORDIC (FMVR-CORDIC) arithmetic complete coordinate conversion is used to increase the speed of ultrasonic scanning imaging. FPGA is used as the kernel module to control data transferring, related circuits and relevant chips' working, and to accomplish data preprocessing. With the advantages of simple structure, nice flexibility and convenience, it satisfies the demand for real-time displaying in this system. Finally, the original polar coordinate image is transformed to rectangular coordinate grey image through coordinate transformation. The system performances have been validated by the experimental result.

  3. Performance of 2-Dimensional Ultrasound Shear Wave Elastography in Liver Fibrosis Detection Using Magnetic Resonance Elastography as the Reference Standard: A Pilot Study.

    PubMed

    Song, Pengfei; Mellema, Daniel C; Sheedy, Shannon P; Meixner, Duane D; Karshen, Ryan M; Urban, Matthew W; Manduca, Armando; Sanchez, William; Callstrom, Matthew R; Greenleaf, James F; Chen, Shigao

    2016-02-01

    To investigate the correlation between 2-dimensional (2D) ultrasound shear wave elastography (SWE) and magnetic resonance elastography (MRE) in liver stiffness measurement and the diagnostic performance of 2D SWE for liver fibrosis when imaging from different intercostal spaces and using MRE as the reference standard. Two-dimensional SWE was performed on 47 patients. One patient was excluded from the study. Each of the remaining 46 patients underwent same-day MRE for clinical purposes. The study was compliant with the Health Insurance Portability and Accountability Act and approved by the Institutional Review Board. Informed consent was obtained from each patient. Two-dimensional SWE measurements were acquired from the ninth, eighth, and seventh intercostal spaces. The correlation with MRE was calculated at each intercostal space and multiple intercostal spaces combined. The performance of 2D SWE in diagnosing liver fibrosis was evaluated by receiver operating characteristic curve analysis using MRE as the standard. The 47 patients who initially underwent 2D SWE included 22 female and 25 male patients (age range, 19-77 years). The highest correlation between 2D SWE and MRE was from the eighth and seventh intercostal spaces (r = 0.68-0.76). The ranges of the areas under the receiver operating characteristic curves for separating normal or inflamed livers from fibrotic livers using MRE as the clinical reference were 0.84 to 0.92 when using the eighth and seventh intercostal spaces individually and 0.89 to 0.90 when combined. The results suggest that 2D SWE and MRE are well correlated when SWE is performed at the eighth and seventh intercostal spaces. The ninth intercostal space is less reliable for diagnosing fibrosis with 2D SWE. Combining measurements from multiple intercostal spaces does not significantly improve the performance of 2D SWE for detection of fibrosis. © 2016 by the American Institute of Ultrasound in Medicine.

  4. Comparison between shear wave dispersion magneto motive ultrasound and transient elastography for measuring tissue-mimicking phantom viscoelasticity.

    PubMed

    Almeida, Thiago W J; Sampaio, Diego R Thomaz; Bruno, Alexandre Colello; Pavan, Theo Z; Carneiro, Antonio A O

    2015-12-01

    Several methods have been developed over the last several years to analyze the mechanical properties of soft tissue. Elastography, for example, was proposed to evaluate soft tissue stiffness in an attempt to reduce the need for invasive procedures, such as breast biopsies; however, its qualitative nature and the fact that it is operator-dependent have proven to be limitations of the technique. Quantitative shearwave- based techniques have been proposed to obtain information about tissue stiffness independent of the operator. This paper describes shear wave dispersion magnetomotive ultrasound (SDMMUS), a new shear-wave-based method in which a viscoelastic medium labeled with iron oxide nanoparticles is displaced by an external tone burst magnetic field. As in magnetomotive ultrasound (MMUS), SDMMUS uses ultrasound to detect internal mechanical vibrations induced by the interaction between a magnetic field and magnetic nanoparticles. These vibrations generated shear waves that were evaluated to estimate the viscoelastic properties of tissue-mimicking phantoms. These phantoms were manufactured with different concentrations of gelatin and labeled with iron oxide nanoparticles. The elasticity and viscosity obtained with SDMMUS agreed well with the results obtained by traditional ultrasound-based transient elastography.

  5. In vivo measurement of rotator cuff tendon strain with ultrasound elastography: an investigation using a porcine model.

    PubMed

    Hatta, Taku; Yamamoto, Nobuyuki; Sano, Hirotaka; Itoi, Eiji

    2014-09-01

    To clarify the relationship between the strain ratio measured by ultrasound elastography and the mechanical properties of the tendon measured by a universal testing machine. We also attempted to determine the effect of the type and depth of soft tissue overlying the tendon on the elastographic measurement. Twelve fresh porcine shoulders were prepared. Elastographic measurement was performed on the infraspinatus tendon by manually applying repetitive compressions from an ultrasound probe with an acoustic coupler consisting of an elastomer with definite elasticity as a reference material. The strain ratio, defined as tendon/reference strain, was obtained by 4 different approaches: with the probe placed on the skin, on the subcutaneous fat after removing the skin, on the muscle after removing the subcutaneous fat, and directly on the tendon. The strain ratios measured by these approaches were compared statistically. The relationship between the depth of the tendon measured on elastography and the strain ratio was also investigated. We also attempted to clarify the relationship between the strain ratio of the tendon and its elastic property. The tendon was mounted on a testing machine, and compressive force was applied. Tendon compliance was calculated as the reciprocal of the Young modulus in the range of 5% to 10% strain, which was compared to its strain ratio. The tendon/reference strain ratio significantly correlated with the tendon compliance (r = 0.73; P < .01). The strain ratio was not affected by differences in the measuring approaches (P = .4) or by the depth to the tendon level (P = .8). Our results indicated that the strain ratio of the rotator cuff tendon could be measured with minimal influence by overlying soft tissues if its depth from the skin was less than 22 mm. We believe that ultrasound elastography would be a useful tool for assessment of tendon elasticity in clinical practice. © 2014 by the American Institute of Ultrasound in Medicine.

  6. Cystic Pancreatic Lymphangioma - Diagnostic Role of Endoscopic Ultrasound.

    PubMed

    Carvalho, Diana; Costa, Mariana; Russo, Pedro; Simas, Luís; Baptista, Teresa; Ramos, Gonçalo

    2016-01-01

    Pancreatic cystic lymphangiomas are rare benign lesions that arise from lymphatic vessels, accounting for less than 0.2% of all pancreatic cysts. Typically it is asymptomatic and discovery occurs during imaging exams for non-pancreatic disease. In the past, a definite diagnosis was made through surgery, with complete resection of all tumoral tissue to prevent recurrence. Nowadays, the development of endoscopic ultrasound (EUS) made it possible to identify these cysts combining morphologic ultrasound features, macroscopic aspirated fluid appearance, biochemical and cytological evaluation of the sample. We report two cases of cystic pancreatic lymphangioma diagnosed through EUS, allowing conservative management without surgery. These cases show that cystic pancreatic lymphangioma should be considered in the differential diagnosis of cystic pancreatic lesions and that EUS is an important tool for their recognition.

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

    PubMed

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

    2016-05-01

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

  8. Ultrasound elastography for carpal tunnel pressure measurement: A cadaveric validation study.

    PubMed

    Kubo, Kazutoshi; Zhou, Boran; Cheng, Yu-Shiuan; Yang, Tai-Hua; Qiang, Bo; An, Kai-Nan; Moran, Steven L; Amadio, Peter C; Zhang, Xiaoming; Zhao, Chunfeng

    2017-07-21

    Carpal tunnel pressure is a key factor in the etiology of carpal tunnel syndrome. Numerous approaches have been conducted to measure carpal tunnel pressure. However, most techniques are invasive and take time and effort. We have developed an innovative approach to noninvasively assess the tunnel pressure by using the ultrasound surface wave elastography (USWE) technique. In a previous study it was shown that the shear wave speed in a tendon increased linearly with increasing tunnel pressure enclosed the tendon in a simple tendon model. This study aimed to examine the relationship between the carpal tunnel pressure and the shear wave speeds inside and outside the carpal tunnel in a human cadaveric model. The result showed that the shear wave speed inside the carpal tunnel increased linearly with created carpal tunnel pressure, while the shear wave speed outside the carpal tunnel remained constant. These findings suggest that noninvasive measurement of carpal tunnel pressure is possible by measuring the shear wave speed in the tendon. After fully establishing this technology and being applicable in clinic, it would be useful in the diagnosis of carpal tunnel syndrome. For that reason, further validation with this technique in both healthy controls and patients with carpal tunnel syndrome is required. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  9. [Ultrasound role in assessment of vesicoureteral reflux endoscopic treatment results].

    PubMed

    Serrano Durba, A; Bonillo García, M A; Domínguez Hinarejos, C; Sanguesa, C; Muro, D; García Ibarra, F

    2006-04-01

    Since the beginning of the application of the RVU treatment, the use of the ultrasound was used taking into account two main indications/symptoms: a) identification of the complications; b) assessment of the result (visualization of the implanted material and the presence of the "uretheral jet" by means or through/of ecodoppler-color). To determine the value of the ultrasound in the assessment of the result of the endoscopic treatment of the RVU and in the detection of its complications. From 2001-2002 we have carried out the endoscopic treatment to an overall of 261 ureteral units of all degree and etiology. 246 were assessed post-operation with an ultrasound per month and all of them were evaluated with a cistography after 3 months. In a random sample of 92 units, the result of the isotopic cistography has been compared with the visualization of the implanted material in the bladder; and in a random sample of 56 units, the result of the isotopic cistography has been compared with the presence of ureteral jet in the study with ecodoppler-color after moisturizing of the patient. In order to do, we have done two corresponding comparative charts 2 x 2 and we have calculated the Sensibility and Specificity of the tests, as well as their predictive positive and negative values, the degree of similarity of both tests with the Kappa index, and the degree of statistical relevance with Chi squared. The ultrasound did not show significant changes if compared to previous studies in 213 units (86,58 %) although in 5 patients an ectasia has been identified as attributed to the treatment. 3 of this patients have developed renoureteral pain, and in 2 pain has spontaneously disappeared as shown in later tests. The S and the E of the presence of implanted material is 94% and 10%respectively and its VPP and VPN of 80% and 10% and estadistical. The S and E of the jet visualization is 82% and 30%, with a VPP of 84% and a VPN of 27%, a level of statistical relevance of 0.836 and a

  10. Endoscopic ultrasound and computer tomography are inaccurate methods of classifying cystic pancreatic lesions.

    PubMed

    Gerke, H; Jaffe, T A; Mitchell, R M; Byrne, M F; Stiffler, H L; Branch, M S; Baillie, J; Jowell, P S

    2006-01-01

    Despite advances in imaging modalities, preoperative diagnosis of pancreatic cystic lesions remains difficult. To assess the accuracy of endoscopic ultrasound and computer tomography to preoperatively distinguish benign from potentially malignant and malignant pancreatic cystic lesions. Photograph series obtained from endoscopic ultrasound examinations of 66 patients with cystic pancreatic lesions were blindly reviewed by three endoscopic ultrasonographers. Forty-one of those 66 patients also underwent a computer tomography scan at our institution, which was blindly reviewed by a single radiologist. Computer tomography and endoscopic ultrasound classification into benign and malignant and potentially malignant pancreatic cystic lesions was correlated with the final diagnosis, which was established by surgical pathology (n = 43), diagnostic fine needle aspiration (n = 13) or follow-up imaging (n = 10). Interobserver agreement was measured using kappa statistics. Endoscopic ultrasound classification by the three examiners into benign versus malignant or potentially malignant cystic lesions was correct in 65-67%. Interobserver agreement was 50%. Kappa values for pairs of endoscopic ultrasound examiners were 0.16, 0.43 and 0.53. Computer tomography classification was correct in 71% and in agreement with the endoscopic ultrasound classification in 56-61% (kappa 0.12 to 0.27). Endoscopic ultrasound and computer tomography cannot accurately distinguish between benign pancreatic cystic lesions and malignant or potentially malignant ones. There is poor-to-modest interobserver agreement in classifying these lesions.

  11. Endoscopic ultrasound and endoscopic retrograde cholangiopancreatography: Can they be successfully combined?

    PubMed

    Gornals, Joan B; Esteban, José Miguel; Guarner-Argente, Carlos; Marra-Lopez, Carlos; Repiso, Alejandro; Sendino, Oriol; Loras, Carme

    2016-11-01

    Endoscopic ultrasound (EUS) and endoscopic retrograde cholangiopancreatography (ERCP) have much in common, including their main indications (biliopancreatic disorders), powerful therapeutic capacities and a steep learning curve. Over the years they have evolved from novel diagnostic procedures to interventional therapeutic techniques, but along different paths (different scopes or devices and endoscopists specializing exclusively in one or the other technique). However, EUS has gradually developed into a therapeutic technique that requires skills in the use of ERCP devices and stents, leading some ERCP specialists to explore the therapeutic potential of EUS. The corresponding literature, which has grown exponentially, includes recent experiments on combining the two techniques, which have gradually come to be used in routine care in a number of centers, with positive technical, clinical and financial outcomes. We review EUS and ERCP as individual or combined procedures for managing biliopancreatic disorders. Copyright © 2016 Elsevier España, S.L.U. y AEEH y AEG. All rights reserved.

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

    PubMed

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

    2016-02-01

    In the last 12 - 18 months nearly all ultrasound manufacturers have arrived to implement ultrasound shear wave elastography modality in their equipment for the assessment of chronic liver disease; the few remaining players are expected to follow in 2016.When all manufacturers rush to a new technology at the same time, it is evident that the clinical demand for this information is of utmost value. Around 1990, there was similar demand for color Doppler ultrasound; high demand for contrast-enhanced ultrasonography was evident at the beginning of this century, and around 2010 demand increased for strain elastography. However, some issues regarding the new shear wave ultrasound technologies must be noted to avoid misuse of the resulting information for clinical decisions. As new articles are expected to appear in 2016 reporting the findings of the new technologies from various companies, we felt that the beginning of this year was the right time to present an appraisal of these issues. We likewise expect that in the meantime EFSUMB will release a new update of the existing guidelines 1 2.The first ultrasound elastography method became available 13 years ago in the form of transient elastography with Fibroscan(®) 3. It was the first technique providing non-invasive quantitive information about the stiffness of the liver and hence regarding the amount of fibrosis in chronic liver disease 3. The innovation was enormous, since a non-invasive modality was finally available to provide findings otherwise achievable only by liver biopsy. In fact, prior to ultrasound elastography, a combination of conventional and Doppler ultrasound parameters were utilized to inform the physician about the presence of cirrhosis and portal hypertension 4. However, skilled operators were required, reproducibility and diagnostic accuracy were suboptimal, and it was not possible to differentiate the pre-cirrhotic stages of fibrosis. All these limitations were substantially improved by

  13. Transient MR elastography (t-MRE) using ultrasound radiation force: theory, safety, and initial experiments in vitro.

    PubMed

    Souchon, Rémi; Salomir, Rares; Beuf, Olivier; Milot, Laurent; Grenier, Denis; Lyonnet, Denis; Chapelon, Jean-Yves; Rouvière, Olivier

    2008-10-01

    The purpose of our study was to assess the feasibility of using ultrasound radiation force as a safe vibration source for transient MR elastography (t-MRE). We present a theoretical framework to predict the phase shift of the complex MRE signal, the temperature elevation due to ultrasound, and safety indicators (I(SPPA), I(SPTA), MI). Next, we report wave images acquired in porcine liver samples in vitro. MR thermometry was used to estimate the temperature elevation induced by ultrasound. Finally, we discuss the implications of our results with regard to the feasibility of using radiation force for t-MRE in a clinical setting, and a specific echo-planar imaging (EPI) MRE sequence is proposed.

  14. The AutoQual ultrasound elastography method for quantitative assessment of lateral strain in post-rupture Achilles tendons.

    PubMed

    Brown, Phillip G; Alsousou, Joseph; Cooper, Ashley; Thompson, Mark S; Noble, J Alison

    2013-10-18

    This paper presents the AutoQual elastography method: a novel algorithm that improves the quality of 2D displacement field calculation from ultrasound radio frequency (RF) sequences of acutely ruptured Achilles tendons to determine image-lateral strain fields and has potential use for ligaments and muscles. This method uses 2D bicubic spline interpolation of the RF signal, Quality Determined Search, Automatic Search Range and Adaptive Block Size components as a novel combination that is designed to improve continuity and decrease displacement field noise, especially in areas of low signal strength. We present a simple experiment for quantitatively comparing the AutoQual method to a multiscale (MS) elastography method from ultrasound RF sequences of a 5% agar phantom for rigid body motion and known lateral strain loads with speeds up to 5mm/s. We finally present examples of four in vivo Achilles tendons in various damage states and with manual or artificially controlled passive flexion of the foot. Results show that the AutoQual method offers a substantial improvement on the MS method, achieving similar performance for rigid body tracking at all speeds, a lower normalized square error at all strains induced and a more continuous strain field at higher compression rates. AutoQual also showed a greater average normalized cross correlation for image blocks in the area of interest, a lower standard deviation of the strain field and a visually more acceptable point tracking for in vivo examples. This work demonstrates lateral ultrasound elastography which is robust to the complex passive motion of the Achilles and to various imaging artifacts associated with imaging tendon rupture. This method potentially has a wide clinical application for assessing in vivo strains in and hence mechanical function of any near skin surface tissues that are longitudinally loaded.

  15. A unified approach to combine temperature estimation and elastography for thermal lesion determination in focused ultrasound thermal therapy.

    PubMed

    Liu, Hao-Li; Li, Meng-Lin; Tsui, Po-Hsiang; Lin, Ming-Shi; Huang, Sheng-Min; Bai, Jing

    2011-01-07

    Sonogram-based temperature estimation and elastography have both shown promise as methods of monitoring focused ultrasound (FUS) treatments to induce thermal ablation in tissue. However, each method has important limitations. Temperature estimates based on echo delays become invalid when the relationship between sound speed and temperature is nonlinear, and are further complicated by thermal expansion and other changes in tissue. Elastography can track thermal lesion formation over a wider range of elasticity, but with low specificity and high noise. Furthermore, this method is poor at small lesion detection. This study proposes integrating the two estimates to improve the quality of monitoring FUS-induced thermal lesions. Our unified computational kernel is tested on three types of phantoms. Experiments with type I and type II phantoms were conducted to calibrate the thermal mapping and elastography methods, respectively. The optimal settings were then used in experiments with the type III phantom, which contains ex vivo swine liver tissue. Three different spatial-peak temporal-average intensities (I(spta); 35, 133 and 240 W cm(-2)) were delivered with a sonication time of 60 s. The new procedure can closely monitor heating while identifying the dimensions of the thermal lesion, and is significantly better at the latter task than either approach alone. This work may help improve the current clinical practice, which employs sonograms to guide the FUS-induced thermal ablation procedure.

  16. A PDE-based Regularization Algorithm toward Reducing Speckle Tracking Noise: A Feasibility Study for Ultrasound Breast Elastography

    PubMed Central

    Guo, Li; Xu, Yan; Xu, Zhengfu; Jiang, Jingfeng

    2015-01-01

    Obtaining accurate ultrasonically-estimated displacements along both axial (parallel to the acoustic beam) and lateral (perpendicular to the beam) directions is an important task for various clinical elastography applications (e.g. modulus reconstruction and temperature imaging). In this study, a partial differential equation (PDE)-based regularization algorithm was proposed to enhance motion tracking accuracy. More specifically, the proposed PDE-based algorithm, utilizing two-dimensional displacement estimates from a conventional elastography system, attempted to iteratively reduce noise contained in the original displacement estimates by mathematical regularization. In this study, the physical constraint used by the above-mentioned mathematical regularization was tissue incompressibility. This proposed algorithm was tested using computer-simulated data, a tissue-mimicking phantom and in vivo breast lesion data. Computer simulation results showed that the method significantly improved the accuracy of lateral tracking (e.g. 17X at 0.5% compression). From in vivo breast lesion data investigated, we have found that, as compared to the conventional method, higher quality axial and lateral strain images (e.g. at least 78% improvements among the estimated contrast-to-noise ratios of lateral strain images) were obtained. Our initial results demonstrated that this conceptually and computationally simple method could be useful to improve the image quality for ultrasound elastography with current clinical equipment as a post-processing tool. PMID:25452434

  17. A unified approach to combine temperature estimation and elastography for thermal lesion determination in focused ultrasound thermal therapy

    NASA Astrophysics Data System (ADS)

    Liu, Hao-Li; Li, Meng-Lin; Tsui, Po-Hsiang; Lin, Ming-Shi; Huang, Sheng-Min; Bai, Jing

    2011-01-01

    Sonogram-based temperature estimation and elastography have both shown promise as methods of monitoring focused ultrasound (FUS) treatments to induce thermal ablation in tissue. However, each method has important limitations. Temperature estimates based on echo delays become invalid when the relationship between sound speed and temperature is nonlinear, and are further complicated by thermal expansion and other changes in tissue. Elastography can track thermal lesion formation over a wider range of elasticity, but with low specificity and high noise. Furthermore, this method is poor at small lesion detection. This study proposes integrating the two estimates to improve the quality of monitoring FUS-induced thermal lesions. Our unified computational kernel is tested on three types of phantoms. Experiments with type I and type II phantoms were conducted to calibrate the thermal mapping and elastography methods, respectively. The optimal settings were then used in experiments with the type III phantom, which contains ex vivo swine liver tissue. Three different spatial-peak temporal-average intensities (Ispta; 35, 133 and 240 W cm-2) were delivered with a sonication time of 60 s. The new procedure can closely monitor heating while identifying the dimensions of the thermal lesion, and is significantly better at the latter task than either approach alone. This work may help improve the current clinical practice, which employs sonograms to guide the FUS-induced thermal ablation procedure.

  18. Strain elastography of abnormal axillary nodes in breast cancer patients does not improve diagnostic accuracy compared with conventional ultrasound alone.

    PubMed

    Park, Young Mi; Fornage, Bruno D; Benveniste, Ana Paula; Fox, Patricia S; Bassett, Roland L; Yang, Wei Tse

    2014-12-01

    The purpose of this study was to determine the diagnostic value of strain elastography (SE) alone and in combination with gray-scale ultrasound in the diagnosis of benign versus metastatic disease for abnormal axillary lymph nodes in breast cancer patients. Patients with breast cancer and axillary lymph nodes suspicious for metastatic disease on conventional ultrasound who underwent SE of the suspicious node before ultrasound-guided fine-needle aspiration biopsy (FNAB) were included in this study. On conventional ultrasound, the long- and short-axis diameters, long-axis-to-short-axis ratio, cortical echogenicity, thickness, and evenness were documented. The nodal vascularity was assessed on power Doppler imaging. Elastograms were evaluated for the percentage of black (hard) areas in the lymph node, and the SE-ultrasound size ratio was calculated. Two readers assessed the images independently and then in consensus in cases of disagreement. ROC AUCs were calculated for conventional ultrasound, SE, and both methods combined. Interreader reliability was assessed using kappa statistics. A total of 101 patients with 104 nodes were examined; 35 nodes were benign, and 69 had metastases. SE alone showed a significantly lower AUC (62%) than did conventional ultrasound (92%) (p<0.001). There was no difference between the AUC of conventional ultrasound and the AUC of the combination of conventional ultrasound and SE (93%) (p=0.16). Interreader reliability was moderate for all variables (κ≥0.60) except the SE-ultrasound size ratio (κ=0.35). Added SE does not improve the diagnostic ability of conventional ultrasound when evaluating abnormal axillary lymph nodes.

  19. The diagnosis value of acoustic radiation force impulse (ARFI) elastography for thyroid malignancy without highly suspicious features on conventional ultrasound

    PubMed Central

    Liu, Bo-Ji; Lu, Feng; Xu, Hui-Xiong; Guo, Le-Hang; Li, Dan-Dan; Bo, Xiao-Wan; Li, Xiao-Long; Zhang, Yi-Feng; Xu, Jun-Mei; Xu, Xiao-Hong; Qu, Shen

    2015-01-01

    Objective: The aim of this study was to evaluate the potential diagnostic performance of acoustic radiation force impulse (ARFI) elastography in identifying malignancy in nodules that do not appear highly suspicious on conventional ultrasound (US). Methods: 330 pathologically confirmed thyroid nodules (40 malignant and 290 benign; mean size, 22.0±11.6 mm) not suspicious of malignancy on conventional US in 330 patients (mean age 52.8±11.7 years) underwent ARFI elastography before surgery. ARFI elastography included qualitative ARFI-induced strain elastography (SE) and quantitative point shear wave elastography (p-SWE). ARFI-induced SE image was assessed by SE score, while p-SWE was denoted with shear wave velocity (SWV, m/s). The diagnostic performance of four criteria sets was evaluated: criteria set 1 (ARFI-induced SE), criteria set 2 (p-SWE), criteria set 3 (either set 1 or 2), criteria set 4 (both set 1 and 2). Receiver operating characteristic curve (ROC) analyses were performed to assess the diagnostic performance. Results: SE score ≥4 was more frequently found in malignant nodules (32/40) than in benign nodules (30/290, P<0.001). The mean SWV of malignant nodules (3.64±2.23 m/s) was significantly higher than that of benign nodules (2.02±0.69 m/s) (P<0.001). ARFI-induced SE (set 1) had a sensitivity of 80.0% (32/40) and a specificity of 89.7% (260/290) with a cut-off point of SE score ≥4; p-SWE (set 2) had a sensitivity of 80.0% (32/40) and a specificity of 57.9% (168/290) with a cut-off point of SWV ≥2.15 m/s. When ARFI-induced SE and p-SWE were combined, set 3 had the highest sensitivity (92.5%, 37/40) while set 4 had the highest specificity (95.2%, 276/290). Conclusion: ARFI elastography can be used for differential diagnosis of malignant thyroid nodules without highly suspicious features on US. The combination of ARFI-induced SE and p-SWE leads to improved sensitivity and specificity. PMID:26629025

  20. Performance of 2-D ultrasound shear wave elastography in liver fibrosis detection using magnetic resonance elastography as the reference standard: A pilot study

    PubMed Central

    Song, Pengfei; Mellema, Daniel C.; Sheedy, Shannon P.; Meixner, Duane D.; Karshen, Ryan M.; Urban, Matthew W.; Manduca, Armando; Sanchez, William; Callstrom, Matthew R.; Greenleaf, James F.; Chen, Shigao

    2015-01-01

    Objective To investigate the correlation between 2-D ultrasound shear wave elastography (SWE) and magnetic resonance elastography (MRE) in liver stiffness measurement and the diagnostic performance of 2-D SWE for liver fibrosis when imaging from different intercostal spaces and using MRE as the reference standard. Methods 2-D SWE was performed on 47 patients (22 females and 25 males, age 19–77) using the GE LOGIQ E9 scanner. Each of the 47 patients had same day MRE obtained for clinical purposes. The study was HIPAA-compliant and approved by the institutional review board. Informed consent was obtained from each subject. 2-D SWE measurements were acquired from the 9th, 8th, and 7th intercostal spaces. Correlation with MRE was calculated at each intercostal space and multiple intercostal spaces combined. The performance of 2-D SWE in diagnosing liver fibrosis was evaluated with receiver operating characteristic (ROC) curve analysis using MRE as the standard. Results The highest correlation between 2-D SWE and MRE was from the 8th and 7th intercostal spaces (r = 0.68 – 0.76). The range of the areas under the ROC curve for separating normal or inflamed livers from fibrotic livers using MRE as the clinical reference were 0.84 – 0.92 when using 8th and 7th intercostal spaces individually, and 0.89 –0.9 when combined. Conclusion The results suggest that 2-D SWE and MRE are well correlated when SWE is performed at the 8th and 7th intercostal spaces. The 9th intercostal space is less reliable for diagnosing fibrosis using 2-D SWE. Combining measurements from multiple intercostal spaces does not significantly improve 2-D SWE performance for the detection of fibrosis. PMID:26782164

  1. Ultrasonic Elastography

    NASA Astrophysics Data System (ADS)

    Souchon, Rémi

    Elastography is a new ultrasound-based imaging technique that provides images (called elastograms) of internal strain in soft tissues under a static compression. The strain is related to the stiffness of the tissues, which is in turn related to the pathological state of tissues. For example, it has been known for long that breast and prostate cancer are stiffer than normal tissues, and palpation is a standard medical practice.

  2. Feasibility and Reliability of Quantifying Passive Muscle Stiffness in Young Children Using Shear Wave Ultrasound Elastography

    PubMed Central

    Brandenburg, Joline E.; Eby, Sarah F.; Song, Pengfei; Zhao, Heng; Landry, Bradford W.; Kingsley-Berg, Shirley; Bamlet, William R.; Chen, Shigao; Sieck, Gary C.; An, Kai-Nan

    2014-01-01

    Objective To investigate the feasibility and reliability of passive muscle stiffness measurements in children through use of shear wave ultrasound elastography. Methods This is a prospective cross -sectional study quantifying the passive stiffness of bilateral lateral gastrocnemii muscles during passive stretch in twenty typically developing children (age range, 2.0–12.6 years). Data collected included passive stiffness of the lateral gastrocnemius muscle (shear modulus in kilopascal [kPa]) at four positions of progressive passive foot dorsiflexion; demographic characteristics of the child participants; and comparison of demographic characteristics with the shear modulus. Results Passive stiffness increased with increasing stretch (mean [SD] range of stretch, 7.1 [2.0]–36.2 [22.0] kPa). For all four foot positions, no significant difference was found between right and left legs (range P=0.42 to P=0.98) or between the sexes (range P=0.28 to P> 0.99). No correlation of passive muscle stiffness to age, body mass index, or ankle range of motion was found. Reliability of measurements was good to excellent (mean [95% CI] range of reliability 0.67 [0.44–0.83] to 0.80 [0.63–0.90]). Conclusions Measurements of passive stiffness of the lateral gastrocnemius muscle are feasible and reliable in children as young as 2 years. Because the present study found no significant difference between sex and the side tested in this age-group, future studies involving children of this age range may not need to be stratified on the basis of these parameters. Defining normal passive muscle stiffness in children is critical for identifying and understanding the implications of abnormal passive muscle stiffness in children with neuromuscular disorders. PMID:25792582

  3. Evaluation of Post-stroke Spastic Muscle Stiffness Using Shear Wave Ultrasound Elastography.

    PubMed

    Wu, Chueh-Hung; Ho, Yu-Chun; Hsiao, Ming-Yen; Chen, Wen-Shiang; Wang, Tyng-Guey

    2017-03-09

    Current clinical evaluations of post-stroke upper limb spasticity are subjective and qualitative. We proposed a quantitative measurement of post-stroke spastic muscle stiffness by using shear-wave ultrasound elastography and tested its reliability. Acoustic radiation force impulse with shear wave velocity (SWV) detection was used to evaluate stiffness of the biceps brachii muscles at 90° and 0° elbow flexion. In 21 control subjects, SWV did not significantly differ between dominant and non-dominant sides at either flexion angle (0°: p = 0.311, 90°: p = 0.436). In 31 patients who had recent stroke, SWV was significantly greater on the paretic side than on the non-paretic side at both 90° (2.23 ± 0.15 m/s vs. 1.88 ± 0.08 m/s, p = 0.036) and 0° (3.28 ± 0.11 m/s vs. 2.93 ± 0.06 m/s, p = 0.002). The physical appearance of arms and forearms of our patients and controls prevented blinding of the rater to paretic or non-paretic side. At 90°, SWV on the paretic side correlated positively with modified Ashworth scale and modified Tardieu scale (spasticity severity) and negatively with Stroke Rehabilitation Assessment of Movement score (motor function impairment). The intra-class correlation coefficients of intra-rater and inter-rater reliability for SWV measurements were classified as excellent. In conclusion, high SWV was associated with high spasticity and poor function of the post-stroke upper limb, suggesting possible use as a reliable quantitative measure for disease progression and treatment follow-up.

  4. A regularization-free elasticity reconstruction method for ultrasound elastography with freehand scan.

    PubMed

    Pan, Xiaochang; Liu, Ke; Bai, Jing; Luo, Jianwen

    2014-09-07

    In ultrasound elastography, reconstruction of tissue elasticity (e.g., Young's modulus) requires regularization and known information of forces and/or displacements on tissue boundaries. In practice, it is challenging to choose an appropriate regularization parameter; and the boundary conditions are difficult to obtain in vivo. The purpose of this study is to develop a more applicable algorithm that does not need any regularization or boundary force/displacement information. The proposed method adopts the bicubic B-spline as the tissue motion model to estimate the displacement fields. Then the estimated displacements are input to the finite element inversion scheme to reconstruct the Young's modulus of each element. In the inversion, a modulus boundary condition is used instead of force/displacement boundary conditions. Simulation and experiments on tissue-mimicking phantoms are carried out to test the proposed method. The simulation results demonstrate that Young's modulus reconstruction of the proposed method has a relative error of -3.43 ± 0.43% and root-squared-mean error of 16.94 ± 0.25%. The phantom experimental results show that the target hardening artifacts in the strain images are significantly reduced in the Young's modulus images. In both simulation and phantom studies, the size and position of inclusions can be accurately depicted in the modulus images. The proposed method can reconstruct tissue Young's modulus distribution with a high accuracy. It can reduce the artifacts shown in the strain image and correctly delineate the locations and sizes of inclusions. Unlike most modulus reconstruction methods, it does not need any regularization during the inversion procedure. Furthermore, it does not need to measure the boundary conditions of displacement or force. Thus this method can be used with a freehand scan, which facilitates its usage in the clinic.

  5. Carotid plaque elasticity estimation using ultrasound elastography, MRI, and inverse FEA - A numerical feasibility study.

    PubMed

    Nieuwstadt, H A; Fekkes, S; Hansen, H H G; de Korte, C L; van der Lugt, A; Wentzel, J J; van der Steen, A F W; Gijsen, F J H

    2015-08-01

    The material properties of atherosclerotic plaques govern the biomechanical environment, which is associated with rupture-risk. We investigated the feasibility of noninvasively estimating carotid plaque component material properties through simulating ultrasound (US) elastography and in vivo magnetic resonance imaging (MRI), and solving the inverse problem with finite element analysis. 2D plaque models were derived from endarterectomy specimens of nine patients. Nonlinear neo-Hookean models (tissue elasticity C1) were assigned to fibrous intima, wall (i.e., media/adventitia), and lipid-rich necrotic core. Finite element analysis was used to simulate clinical cross-sectional US strain imaging. Computer-simulated, single-slice in vivo MR images were segmented by two MR readers. We investigated multiple scenarios for plaque model elasticity, and consistently found clear separations between estimated tissue elasticity values. The intima C1 (160 kPa scenario) was estimated as 125.8 ± 19.4 kPa (reader 1) and 128.9 ± 24.8 kPa (reader 2). The lipid-rich necrotic core C1 (5 kPa) was estimated as 5.6 ± 2.0 kPa (reader 1) and 8.5 ± 4.5 kPa (reader 2). A scenario with a stiffer wall yielded similar results, while realistic US strain noise and rotating the models had little influence, thus demonstrating robustness of the procedure. The promising findings of this computer-simulation study stimulate applying the proposed methodology in a clinical setting.

  6. A Hertzian contact mechanics based formulation to improve ultrasound elastography assessment of uterine cervical tissue stiffness.

    PubMed

    Briggs, Brandi N; Stender, Michael E; Muljadi, Patrick M; Donnelly, Meghan A; Winn, Virginia D; Ferguson, Virginia L

    2015-06-25

    Clinical practice requires improved techniques to assess human cervical tissue properties, especially at the internal os, or orifice, of the uterine cervix. Ultrasound elastography (UE) holds promise for non-invasively monitoring cervical stiffness throughout pregnancy. However, this technique provides qualitative strain images that cannot be linked to a material property (e.g., Young's modulus) without knowledge of the contact pressure under a rounded transvaginal transducer probe and correction for the resulting non-uniform strain dissipation. One technique to standardize elastogram images incorporates a material of known properties and uses one-dimensional, uniaxial Hooke's law to calculate Young's modulus within the compressed material half-space. However, this method does not account for strain dissipation and the strains that evolve in three-dimensional space. We demonstrate that an analytical approach based on 3D Hertzian contact mechanics provides a reasonable first approximation to correct for UE strain dissipation underneath a round transvaginal transducer probe and thus improves UE-derived estimates of tissue modulus. We validate the proposed analytical solution and evaluate sources of error using a finite element model. As compared to 1D uniaxial Hooke's law, the Hertzian contact-based solution yields significantly improved Young's modulus predictions in three homogeneous gelatin tissue phantoms possessing different moduli. We also demonstrate the feasibility of using this technique to image human cervical tissue, where UE-derived moduli estimations for the uterine cervix anterior lip agreed well with published, experimentally obtained values. Overall, UE with an attached reference standard and a Hertzian contact-based correction holds promise for improving quantitative estimates of cervical tissue modulus. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Clinical, endoscopic and endoscopic ultrasound features of duodenal varices: A report of 10 cases

    PubMed Central

    Rana, Surinder Singh; Bhasin, Deepak Kumar; Sharma, Vishal; Chaudhary, Vinita; Sharma, Ravi; Singh, Kartar

    2014-01-01

    Background: Duodenal varices (DV) although an uncommon cause, are an important cause due to the severe nature of the bleed and associated adverse outcome. Materials and Methods: We retrospectively evaluated patients with DV seen at our institution over past 4 years. Results: A total of 10 patients (nine males; mean age was 35.8 ± 7.68 years) with DV were studied. Five patients had underlying cirrhosis and five had DV because of non-cirrhotic portal hypertension (four patients had extra-hepatic portal venous obstruction and one patient had non-cirrhotic portal fibrosis). Five patients presented with upper gastrointestinal (GI) bleed, whereas in the remaining five patients DV were detected on endoscopy performed for evaluation of portal hypertension. Endoscopy revealed submucosal lesion in nine patients, whereas in one patient an initial endoscopic diagnosis of Dieulafoy's lesion was made. However endoscopic ultrasound (EUS) could clearly identify DV in all patients. Of five patients presenting with upper GI bleed, three had the esophageal varices eradicated and two presented 1st time with bleed form DV and did not have esophagogastric varices. All patients with acute upper GI bleed were initially treated with intravenous terlipressin followed by glue (n-butyl cyanoacrylate) injection in 4/5 patients with one patient refusing further endoscopic therapy. The variceal obliteration was documented by EUS in all these four patients and there has been no recurrence of bleed in these four patients over a follow-up period of 4-46 months. The five non-bleeding DV were already on beta- blockers and the same were continued. Two of these five patients succumbed to progressive liver failure with none of these five patients having GI bleed on follow-up. Conclusion: EUS is a useful investigational modality for evaluating patients with DV and endoscopic injection of glue is an effective therapy for controlling and preventing recurrence of bleed from DV. PMID:24949411

  8. Reconstruction of elasticity: a stochastic model-based approach in ultrasound elastography

    PubMed Central

    2013-01-01

    Background The convectional strain-based algorithm has been widely utilized in clinical practice. It can only provide the information of relative information of tissue stiffness. However, the exact information of tissue stiffness should be valuable for clinical diagnosis and treatment. Methods In this study we propose a reconstruction strategy to recover the mechanical properties of the tissue. After the discrepancies between the biomechanical model and data are modeled as the process noise, and the biomechanical model constraint is transformed into a state space representation the reconstruction of elasticity can be accomplished through one filtering identification process, which is to recursively estimate the material properties and kinematic functions from ultrasound data according to the minimum mean square error (MMSE) criteria. In the implementation of this model-based algorithm, the linear isotropic elasticity is adopted as the biomechanical constraint. The estimation of kinematic functions (i.e., the full displacement and velocity field), and the distribution of Young’s modulus are computed simultaneously through an extended Kalman filter (EKF). Results In the following experiments the accuracy and robustness of this filtering framework is first evaluated on synthetic data in controlled conditions, and the performance of this framework is then evaluated in the real data collected from elastography phantom and patients using the ultrasound system. Quantitative analysis verifies that strain fields estimated by our filtering strategy are more closer to the ground truth. The distribution of Young’s modulus is also well estimated. Further, the effects of measurement noise and process noise have been investigated as well. Conclusions The advantage of this model-based algorithm over the conventional strain-based algorithm is its potential of providing the distribution of elasticity under a proper biomechanical model constraint. We address the model

  9. Reconstruction of elasticity: a stochastic model-based approach in ultrasound elastography.

    PubMed

    Lu, Minhua; Zhang, Heye; Wang, Jun; Yuan, Jinwei; Hu, Zhenghui; Liu, Huafeng

    2013-08-10

    The convectional strain-based algorithm has been widely utilized in clinical practice. It can only provide the information of relative information of tissue stiffness. However, the exact information of tissue stiffness should be valuable for clinical diagnosis and treatment. In this study we propose a reconstruction strategy to recover the mechanical properties of the tissue. After the discrepancies between the biomechanical model and data are modeled as the process noise, and the biomechanical model constraint is transformed into a state space representation the reconstruction of elasticity can be accomplished through one filtering identification process, which is to recursively estimate the material properties and kinematic functions from ultrasound data according to the minimum mean square error (MMSE) criteria. In the implementation of this model-based algorithm, the linear isotropic elasticity is adopted as the biomechanical constraint. The estimation of kinematic functions (i.e., the full displacement and velocity field), and the distribution of Young's modulus are computed simultaneously through an extended Kalman filter (EKF). In the following experiments the accuracy and robustness of this filtering framework is first evaluated on synthetic data in controlled conditions, and the performance of this framework is then evaluated in the real data collected from elastography phantom and patients using the ultrasound system. Quantitative analysis verifies that strain fields estimated by our filtering strategy are more closer to the ground truth. The distribution of Young's modulus is also well estimated. Further, the effects of measurement noise and process noise have been investigated as well. The advantage of this model-based algorithm over the conventional strain-based algorithm is its potential of providing the distribution of elasticity under a proper biomechanical model constraint. We address the model-data discrepancy and measurement noise by introducing

  10. Endoscopic ultrasound-fine needle injection for oncological therapy

    PubMed Central

    Kaplan, Jeremy; Khalid, Amaara; Cosgrove, Natalie; Soomro, Ayesha; Mazhar, Syed Mohsin; Siddiqui, Ali A

    2015-01-01

    The minimal invasiveness and precision of endoscopic ultrasound (EUS) has lead to both its widespread use as a diagnostic and staging modality for gastrointestinal and pancreaticobiliary malignancies, and to its expanding role as a therapeutic modality. EUS-guided celiac plexus neurolysis is now a well-accepted modality for palliation of pain in patients with pancreatic cancer. EUS-guided ablation, brachytherapy, fiducial marker placement, and antitumor agent injection have been described as methods of performing minimally invasive oncological therapy. EUS-fine needle injection may be performed as adjunctive, alternative, or palliative treatment. This review summarizes the studies to date that have described these methods. A literature search using the PubMed/MEDLINE databases was performed. While most published studies to date are limited with disappointing outcomes, the concept of a role of EUS in oncological therapy seems promising. PMID:26691224

  11. New Scopes, New Accessories, New Stents for Interventional Endoscopic Ultrasound

    PubMed Central

    Chapman, Christopher G.; Siddiqui, Uzma D.

    2016-01-01

    Technological advances have rapidly expanded the therapeutic potential of endoscopic ultrasound (EUS). Innovations in stent technology; directed adjunctive therapy for pancreatic tumors, including radiofrequency ablation and fiducial marker placement; advanced imaging modalities, including needle-based confocal laser endomicroscopy; and new echoendoscopes, such as the forward-viewing linear echoendoscope, are emerging as safe and effective tools and devices for providing a broad range of treatments and therapies previously not thought possible. In this review, we summarize and discuss the new echoendoscopes, accessories, and stents for interventional EUS and highlight the recent literature on technical and therapeutic efficacy. The therapeutic role and indications for EUS are rapidly evolving well beyond its current limits as new EUS-specific designed tools are designed, and ultimately, should help achieve the goal of improving patient outcomes. PMID:26855923

  12. Endoscopic ultrasound in the papilla and the periampullary region.

    PubMed

    Castillo, Cecilia

    2010-08-16

    Endoscopic ultrasound (EUS) provides relevant information when an ampullary or periampullary tumor is suspected. Early detection, T and N staging and Fine Needle Aspiration plus cithologic confirmation, are some of the expected benefits. Exclusion of benign findings like choledocholithiasis or chronic pancreatitis is also important. A correct understanding of the complex ampullary and periampullary anatomy is needed. Knowledge of the individual clinical history and other previous diagnostic images all contribute to a successful EUS examination. Radial and lineal EUS images are uniquely detailed and, at the moment, it seems to be the best way to exclude or confirm malignant or benign findings. We propose a procedural algorithm, including EUS, for suspected ampullary or periampullary tumors. This review summarizes the vast amount of information to be found spread in the literature, and recognizes this small anatomic area as the origin for a clinical entity with proper clinical presentation, proper imaging and proper therapeutic resolutions. The benefits of performing EUS for its study are highlighted.

  13. Duplication cysts: Diagnosis, management, and the role of endoscopic ultrasound.

    PubMed

    Liu, Roy; Adler, Douglas G

    2014-07-01

    Gastrointestinal tract duplication cysts are rare congenital gastrointestinal malformation in young patients and adults. They consist of foregut duplication cysts, small bowel duplication cysts, and large bowel duplication cysts. Endoscopic ultrasound (EUS) has been widely used as a modality for the evaluation and diagnosis of duplication cysts. EUS is the diagnostic tool of choice to investigate duplication cysts since it can distinguish between solid and cystic lesions. The question of whether or not to perform EUS-fine needle aspiration (EUS-FNA) on a lesion suspected of being a duplication cyst is controversial as these lesions can become infected with significant consequences, although EUS-FNA is often required to obtain a definitive diagnosis and to rule out more ominous lesions. This manuscript will review the literature on duplication cysts throughout the body and will also focus on the role of EUS and FNA with regards to these lesions.

  14. Endoscopic ultrasound-guided interventions in special situations

    PubMed Central

    Prachayakul, Varayu; Aswakul, Pitulak

    2016-01-01

    Endoscopic ultrasound (EUS) was introduced in 1982 and has since become a popular advanced procedure for diagnosis and therapeutic intervention. Initially, EUS was most commonly used for the diagnosis of pancreatobiliary diseases and tissue acquisition. EUS was first used for guided cholangiography in 1996, followed by EUS-guided biliary drainage in 2001. Advancements in equipment and endoscopic accessories have led to an expansion of EUS-guided procedures, which now include EUS-guided drainage of intra-abdominal abscesses or collections, intra-vascular treatment of refractory variceal and nonvariceal bleeding, transmural pancreatic drainage, common bile duct stone clearance, enteral feeding tube placement and entero-enteric anastomosis. Patients with surgically altered upper gastrointestinal anatomies have greatly benefited from EUS also. This systematic review describes and discusses EUS procedures performed in uncommon diseases and conditions, as well as applications on more vulnerable patients such as young children and pregnant women. In these cases, routine approaches do not always apply, and thus may require the use of innovative and unconventional techniques. Increased knowledge of such special applications will help increase the success rates of these procedures and provide a foundation for additional advances and utilizations of the technique. PMID:26839650

  15. Clinical effects of eosinophilic esophagitis observed using endoscopic ultrasound.

    PubMed

    Yamabe, Akane; Irisawa, Atsushi; Shibukawa, Goro; Abe, Yoko; Saito, Akiko; Imbe, Koh; Hoshi, Koki; Igarashi, Ryo

    2014-08-01

    A 50-year-old woman was referred to our hospital for dysphagia and several episodes of esophageal food impaction during the prior three months. Complete blood count and basic biochemical tests were normal. No eosinophilia was found. Esophagogastroduodenoscopy (EGD) revealed the presence of concentric rings (esophageal "trachealization") and stenosis along the middle and distal esophagus. Endoscopic ultrasound (EUS) showed circumferential thickening of all layers in the same part. Cytopathologic evaluation of a specimen obtained by endoscopic biopsy of the thickened area in the distal esophagus showed eosinophilic infiltration (20 eosinophils per high-powered field). She was diagnosed as having eosinophilic esophagitis (EoE). Topical steroid therapy was started. A tendency of dysphagia for relief and improvement of characteristic EGD findings began early, but wall thickening in EUS remained. Past reports of the related literature have described that thickness of submucosa and muscularis propria remained after therapy, although significant reduction in the mucosal thickness was provided by short-term steroid therapy. One explanation for early relapse is insufficient reduction in the submucosa and muscularis propria. Consequently, our patient was given steroids until thickness on EUS improved. EUS is regarded as useful for evaluating the curative effect in patients with EoE.

  16. Technical tips for endoscopic ultrasound-guided hepaticogastrostomy

    PubMed Central

    Ogura, Takeshi; Higuchi, Kazuhide

    2016-01-01

    Interventional procedures using endoscopic ultrasound (EUS) have recently been developed. For biliary drainage, EUS-guided trans-luminal drainage has been reported. In this procedure, the transduodenal approach for extrahepatic bile ducts is called EUS-guided choledochoduodenostomy, and the transgastric approach for intrahepatic bile ducts is called EUS-guided hepaticogastrostomy (EUS-HGS). These procedures have several effects, such as internal drainage and avoiding post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis, and they are indicated for an inaccessible ampulla of Vater due to duodenal obstruction or surgical anatomy. EUS-HGS has particularly wide indications and clinical impact as an alternative biliary drainage method. In this procedure, it is necessary to dilate the fistula, and several devices and approaches have been reported. Stent selection is also important. In previous reports, the overall technical success rate was 82% (221/270), the clinical success rate was 97% (218/225), and the overall adverse event rate for EUS-HGS was 23% (62/270). Adverse events of EUS-biliary drainage are still high compared with ERCP or PTCD. EUS-HGS should continue to be performed by experienced endoscopists who can use various strategies when adverse events occur. PMID:27099437

  17. Diagnostic Criteria and Accuracy of Categorizing Malignant Thyroid Nodules by Ultrasonography and Ultrasound Elastography with Pathologic Correlation.

    PubMed

    Elsayed, Naglaa Mostafa; Elkhatib, Yasser Atta

    2016-03-01

    Thyroid nodules are a common medical and surgical concern. Thyroid ultrasound (US) is the primary imaging modality used for initial evaluation and assortment of nodules for fine needle aspiration (FNA) cytology/biopsy. Ultrasound elastography (USE) is believed to improve the diagnostic accuracy of US in distinguishing benign from malignant nodules. The aim of the work described here is to evaluate the diagnostic criteria and accuracy of US and USE in the diagnosis of malignant thyroid nodules. A prospective study of 88 patients who have thyroid nodules was performed. US, color Doppler, and USE were evaluated using a Philips iU22 equipped with a 5 to 12 MHz, linear transducer, followed by FNA of the each scanned nodule. The most sensitive US criteria for malignant nodules were a height-to-width ratio greater than one and the absence of a halo sign (sensitivity 0.875% and 1.000%, respectively). The most specific criteria for malignancy were a spiculated/blurred margin and the presence of microcalcifications (specificity 0.968% and 0.888%, respectively). The receiver operating characteristic curve showed that the cutoff diagnostic criteria of malignancy are two US characteristics and an elastography score of 4. The diagnostic accuracy of US for malignant thyroid nodules increases by combining US and USE.

  18. A scanning-mode 2D shear wave imaging (s2D-SWI) system for ultrasound elastography.

    PubMed

    Qiu, Weibao; Wang, Congzhi; Li, Yongchuan; Zhou, Juan; Yang, Ge; Xiao, Yang; Feng, Ge; Jin, Qiaofeng; Mu, Peitian; Qian, Ming; Zheng, Hairong

    2015-09-01

    Ultrasound elastography is widely used for the non-invasive measurement of tissue elasticity properties. Shear wave imaging (SWI) is a quantitative method for assessing tissue stiffness. SWI has been demonstrated to be less operator dependent than quasi-static elastography, and has the ability to acquire quantitative elasticity information in contrast with acoustic radiation force impulse (ARFI) imaging. However, traditional SWI implementations cannot acquire two dimensional (2D) quantitative images of the tissue elasticity distribution. This study proposes and evaluates a scanning-mode 2D SWI (s2D-SWI) system. The hardware and image processing algorithms are presented in detail. Programmable devices are used to support flexible control of the system and the image processing algorithms. An analytic signal based cross-correlation method and a Radon transformation based shear wave speed determination method are proposed, which can be implemented using parallel computation. Imaging of tissue mimicking phantoms, and in vitro, and in vivo imaging test are conducted to demonstrate the performance of the proposed system. The s2D-SWI system represents a new choice for the quantitative mapping of tissue elasticity, and has great potential for implementation in commercial ultrasound scanners.

  19. Endoscopic Ultrasound Does Not Accurately Stage Early Adenocarcinoma or High-Grade Dysplasia of the Esophagus

    DTIC Science & Technology

    2010-01-01

    MeSH search terms: " endoscopic ultrasound," "Barrett’s esophagus ," "adeno· carcinoma," "Barrett’s esophagus and high grade dyspla.c;ia...adenocarcinoma of the esophagus ; EMR, endoscopic mucosal resection; EUS, endoscopic ul- trasound; HGD, high-grade dysplasia. <D 2010 by the AGA Institute... esophagus and early adenocarcinoma found EUS examination to have perfecr accuracy for differentiating Tl CLINICAL GASTROENTEROLOGY AND HEPATOLOGY Vol

  20. Solid hypo-echoic thyroid nodules on ultrasound: the diagnostic value of acoustic radiation force impulse elastography.

    PubMed

    Xu, Jun-Mei; Xu, Hui-Xiong; Xu, Xiao-Hong; Liu, Chang; Zhang, Yi-Feng; Guo, Le-Hang; Liu, Lin-Na; Zhang, Jin

    2014-09-01

    The aim of the study described here was to evaluate the diagnostic performance of acoustic radiation force impulse (ARFI) elastography in the differential diagnosis between benign and malignant solid hypo-echoic thyroid nodules (SHTNs) on ultrasound. In this retrospective study, 183 histologically proven SHTNs in 159 patients were enrolled. Conventional US, as well as Virtual Touch tissue imaging (VTI) and Virtual Touch tissue quantification (VTQ) of ARFI elastography, was performed on each nodule. The VTI features of SHTNs were divided into six grades, where higher grades represent harder tissue. VTQ was expressed as shear wave velocity, where higher shear wave velocity values indicate stiffer tissue. The sensitivity, specificity, accuracy, positive predictive value, negative predictive value and Youden index for ultrasound and ARFI were assessed. The 183 pathologically proven SHTNs included 117 benign and 66 malignant lesions. Nodules classified as VTI grades IV to VI were more frequently malignant (49/66, 74.2%) than benign (10/117, 8.5%) (p < 0.001). The mean shear wave velocity of VTQ for malignant SHTNs (mean ± standard deviation, 4.65 ± 2.68 m/s; range, 1.36-9 m/s) was significantly higher than that for benign SHTNs (2.34 ± 0.85 m/s, 0-5.7 m/s) (p < 0.001). The sensitivity, specificity, accuracy, positive predictive value, negative predictive value and Youden index were 27.3%-84.8%, 13.7%-89.7%, 39.3%-69.4%, 35.7%-60%, 61.5%-78.5%, and -0.015 to 0.37 for ultrasound; 68.2%, 76.9%, 73.8%, 62.5%, 81.1% and 0.451 for VTQ; and 74.2%, 91.5%, 85.2%, 83.1%, 86.3% and 0.657 for VTI, respectively. ARFI elastography performed at a superior level, compared with conventional ultrasound, in the differential diagnosis between malignant and benign SHTNs. The diagnostic performance of VTI is higher than that of VTQ.

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

    PubMed

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

    2017-10-01

    In previous studies of acoustic radiation force impulse (ARFI) elastography, using Virtual Touch tissue quantification (VTQ) (Siemens Acuson S2000), it was reported that the measurement of renal shear wave speed in patients with chronic kidney disease (CKD) is not influenced exclusively by renal fibrosis. The purpose of the present study was to analyze the role of VTQ in patients with diabetic kidney disease, considered the main cause of CKD. The study group included 164 patients: 80 patients with diabetic kidney disease (DKD) and 84 without renal disease or diabetes mellitus. In each subject in lateral decubitus, five valid VTQ measurements were performed in each kidney and a median value was calculated, the result being expressed in meters/second. The following means of the median values were obtained In DKD patients, the means of the median values were for VTQ right kidney, 2.21 ± 0.71 m/s, and for VTQ left kidney, 2.13 ± 0.72 m/s, whereas in the normal controls statistically significant higher values were obtained: 2.58 ± 0.78 m/s for VTQ right kidney (p = 0.0017) and 2.46 ± 0.81 m/s for VTQ left kidney (p = 0.006). Patients with an estimated glomerular filtration rate (eGFR) >60 mL/min (DKD stages 1 and 2 together with normal controls) had a significantly higher kidney shear wave speed compared with patients with an eGFR <60 mL/min (2.53 m/s vs. 2.09 m/s, p < 0.05). In the DKD group, there was a significant correlation between eGFR and VTQ levels for the right kidney (r = 0.28, p = 0.04). There was no correlation of VTQ values with proteinuria level, stage of diabetic retinopathy or glycated hemoglobin. Our study indicates that shear wave speed values in patients with diabetic kidney disease and eGFRs <60 mL/min are significantly lower compared with those of patients with eGFRs >60 mL/min (either normal controls or diabetic patients with DKD stages 1 and 2), and values decrease with the decrease in eGFR. However, proteinuria

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

    PubMed

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

    2014-01-01

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

  3. 3-D visualization and non-linear tissue classification of breast tumors using ultrasound elastography in vivo.

    PubMed

    Sayed, Ahmed; Layne, Ginger; Abraham, Jame; Mukdadi, Osama M

    2014-07-01

    The goal of the study described here was to introduce new methods for the classification and visualization of human breast tumors using 3-D ultrasound elastography. A tumor's type, shape and size are key features that can help the physician to decide the sort and extent of necessary treatment. In this work, tumor type, being either benign or malignant, was classified non-invasively for nine volunteer patients. The classification was based on estimating four parameters that reflect the tumor's non-linear biomechanical behavior, under multi-compression levels. Tumor prognosis using non-linear elastography was confirmed with biopsy as a gold standard. Three tissue classification parameters were found to be statistically significant with a p-value < 0.05, whereas the fourth non-linear parameter was highly significant, having a p-value < 0.001. Furthermore, each breast tumor's shape and size were estimated in vivo using 3-D elastography, and were enhanced using interactive segmentation. Segmentation with level sets was used to isolate the stiff tumor from the surrounding soft tissue. Segmentation also provided a reliable means to estimate tumors volumes. Four volumetric strains were investigated: the traditional normal axial strain, the first principal strain, von Mises strain and maximum shear strain. It was noted that these strains can provide varying degrees of boundary enhancement to the stiff tumor in the constructed elastograms. The enhanced boundary improved the performance of the segmentation process. In summary, the proposed methods can be employed as a 3-D non-invasive tool for characterization of breast tumors, and may provide early prognosis with minimal pain, as well as diminish the risk of late-stage breast cancer.

  4. Real-time 1-D/2-D transient elastography on a standard ultrasound scanner using mechanically induced vibration.

    PubMed

    Azar, Reza Zahiri; Dickie, Kris; Pelissier, Laurent

    2012-10-01

    Transient elastography has been well established in the literature as a means of assessing the elasticity of soft tissue. In this technique, tissue elasticity is estimated from the study of the propagation of the transient shear waves induced by an external or internal source of vibration. Previous studies have focused mainly on custom single-element transducers and ultrafast scanners which are not available in a typical clinical setup. In this work, we report the design and implementation of a transient elastography system on a standard ultrasound scanner that enables quantitative assessment of tissue elasticity in real-time. Two new custom imaging modes are introduced that enable the system to image the axial component of the transient shear wave, in response to an externally induced vibration, in both 1-D and 2-D. Elasticity reconstruction algorithms that estimate the tissue elasticity from these transient waves are also presented. Simulation results are provided to show the advantages and limitations of the proposed system. The performance of the system is also validated experimentally using a commercial elasticity phantom.

  5. An evaluation of ocular elasticity using real-time ultrasound elastography in primary open-angle glaucoma.

    PubMed

    Agladioglu, Kadir; Pekel, Gökhan; Altintas Kasikci, Seher; Yagci, Ramazan; Kiroglu, Yilmaz

    2016-01-01

    The aim of this study was to compare sonoelastographic findings in the retina-choroid-sclera (RCS) complex and vitreous in glaucomatous and healthy eyes. For this cross-sectional comparative study, 20 patients with primary open-angle glaucoma and 20 healthy volunteers were recruited. Ultrasound elastography measurements were taken with a sonographic scanner of the RCS complex, anterior vitreous (AV), posterior vitreous (PV), retrobulbar fat tissue (RFT), optic disc (OD) and optic nerve (ON) in each eye. The elasticity index of the RCS complex, RFT, OD, ON, AV and PV was similar in both groups (p  >  0.05), although the AV/PV strain ratio in the group of patients with glaucoma was significantly higher (p  =  0.04). Glaucoma increases the AV/PV strain ratio. In providing reproducible and consistent values, the real-time elastography (RTE) technique may be helpful in elucidating the mechanisms of glaucoma in some aspects. This study can help to evaluate the elasticity of the RCS complex and vitreous in glaucomatous eyes with RTE.

  6. EFSUMB guidelines and recommendations on the clinical use of ultrasound elastography. Part 1: Basic principles and technology.

    PubMed

    Bamber, J; Cosgrove, D; Dietrich, C F; Fromageau, J; Bojunga, J; Calliada, F; Cantisani, V; Correas, J-M; D'Onofrio, M; Drakonaki, E E; Fink, M; Friedrich-Rust, M; Gilja, O H; Havre, R F; Jenssen, C; Klauser, A S; Ohlinger, R; Saftoiu, A; Schaefer, F; Sporea, I; Piscaglia, F

    2013-04-01

    The technical part of these Guidelines and Recommendations, produced under the auspices of EFSUMB, provides an introduction to the physical principles and technology on which all forms of current commercially available ultrasound elastography are based. A difference in shear modulus is the common underlying physical mechanism that provides tissue contrast in all elastograms. The relationship between the alternative technologies is considered in terms of the method used to take advantage of this. The practical advantages and disadvantages associated with each of the techniques are described, and guidance is provided on optimisation of scanning technique, image display, image interpretation and some of the known image artefacts. © Georg Thieme Verlag KG Stuttgart · New York.

  7. Endoscopic ultrasound description of liver segmentation and anatomy.

    PubMed

    Bhatia, Vikram; Hijioka, Susumu; Hara, Kazuo; Mizuno, Nobumasa; Imaoka, Hiroshi; Yamao, Kenji

    2014-05-01

    Endoscopic ultrasound (EUS) can demonstrate the detailed anatomy of the liver from the transgastric and transduodenal routes. Most of the liver segments can be imaged with EUS, except the right posterior segments. The intrahepatic vascular landmarks include the major hepatic veins, portal vein radicals, hepatic arterial branches, and the inferior vena cava, and the venosum and teres ligaments are other important intrahepatic landmarks. The liver hilum and gallbladder serve as useful surface landmarks. Deciphering liver segmentation and anatomy by EUS requires orienting the scan planes with these landmarkstructures, and is different from the static cross-sectional radiological images. Orientation during EUS requires appreciation of the numerous scan planes possible in real-time, and the direction of scanning from the stomach and duodenal bulb. We describe EUS imaging of the liver with a curved linear probe in a step-by-step approach, with the relevant anatomical details, potential applications, and pitfalls of this novel EUS application. © 2013 The Authors. Digestive Endoscopy © 2013 Japan Gastroenterological Endoscopy Society.

  8. Portal cavernoma cholangiopathy: an endoscopic ultrasound based imaging approach.

    PubMed

    Sharma, Malay; Rameshbabu, Chittapuram S

    2014-02-01

    In patients with portal cavernoma cholangiopathy (PCC), appearance and location of collateral channels depends on extent and location of occlusive thrombus in the porto-mesenteric venous system. If the porto-mesenteric venous system is occluded near the formation of portal vein, blood tends to flow through collateral channels that form varices in and around the common bile duct. Though endoscopic ultrasound (EUS) is considered the investigative modality of choice for evaluating common bile duct obstruction, its role in evaluating collateral pathways in and around the common bile duct is poorly defined. This article reviews the anatomy, genesis and appearance of these collateral pathways in PCC. EUS identifies different layers of the common bile duct (CBD) wall and, in PCC, where varices are in close contact with or part of these different layers, can establish the relationship between them. Thus, EUS appears to be the investigation of choice for tracing the origin and course of collaterals in PCC. Careful study of varices in the common bile duct wall prior to ERCP for bile duct stones or biliary strictures may help to plan the procedure and to manage anticipated complications such as hemobilia.

  9. Endoscopic ultrasound-guided celiac plexus block and neurolysis.

    PubMed

    Yasuda, Ichiro; Wang, Hsiu-Po

    2017-05-01

    Endoscopic ultrasound-guided celiac plexus neurolysis (EUS-CPN) is widely used for reducing pain originating from upper abdominal organs. It is mainly indicated to treat pancreatic cancer pain, but also to relieve pain as a result of chronic pancreatitis. Real-time guidance and color Doppler imaging by EUS made the procedure easier and safer, resulting in greater pain relief. Currently, two techniques are used for EUS-CPN. The classic approach, known as the central technique, involves injection of a neurolytic agent at the base of the celiac axis. In the bilateral technique, the neurolytic agent is injected on both sides of the celiac axis. In addition, EUS-guided direct celiac ganglia neurolysis (EUS-CGN) was introduced recently. Pain relief is achieved by EUS-CPN in 70-80% of patients with pancreatic cancer and in 50-60% of those with chronic pancreatitis. The bilateral technique may be more efficient than the central technique, although the central technique is easier and possibly safer. Moreover, EUS-CGN may provide greater pain relief than conventional EUS-CPN. Procedure-related complications include transient pain exacerbation, transient hypotension, transient diarrhea, and inebriation. Although most complications are not serious, major adverse events such as retroperitoneal bleeding, abscess, and ischemic complications occasionally occur. © 2017 Japan Gastroenterological Endoscopy Society.

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

    PubMed Central

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

    2017-01-01

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

  11. New developments in endoscopic ultrasound-guided therapies.

    PubMed

    Bhutani, Manoop S; Arora, Ayush

    2015-01-01

    Endoscopic ultrasound (EUS) has opened new horizons in minimally invasive therapies for diverse gastrointestinal pathologies. Digestive Disease Weak 2015 held in Washington, DC., USA featured exciting research articles on EUS-guided therapeutic procedures. EUS-guided biliary drainage has been attempted and described for many years. There seems to be a lot of interest among various international groups to compare this technique with other alternatives in terms of efficacy and safety. Similarly, EUS-guided pancreatic drainage of cysts and fluid collections continues to evolve with new stents and devices being developed specifically for deployment under endosonographic guidance. EUS-guided ablation of cystic pancreatic tumors is innovative but not always effective. Combining alcohol ablation with injecting chemotherapeutic agents may improve long-term results regarding efficacy. Similarly, for solid pancreatic tumors there appears to be ongoing interest and continuing efforts in injecting different chemotherapeutic or ablative agents, delivering fiducials for radiation guidance and even attempting ablation with radiofrequency. Gastric variceal treatment and EUS-guided anastomoses also continue to be investigated. This review article is focused on the recent developments in EUS-guided therapies presented at Digestive Disease Week (DDW) 2015.

  12. The role of endoscopic ultrasound in pancreatic cancer screening

    PubMed Central

    Bhutani, Manoop S.; Koduru, Pramoda; Joshi, Virendra; Saxena, Payal; Suzuki, Rei; Irisawa, Atsushi; Yamao, Kenji

    2016-01-01

    Pancreatic cancer (PC) is a highly lethal cancer. Despite a significant advancement in cancer treatment, the mortality rate of PC is nearly identical to the incidence rates. Early detection of tumor or its precursor lesions with dysplasia may be the most effective approach to improve survival. Screening strategies should include identification of the population at high risk of developing PC, and an intense application of screening tools with adequate sensitivity to detect PC at an early curable stage. Endoscopic ultrasound (EUS) and magnetic resonance imaging (MRI) seem to be the most promising modalities for PC screening based on the data so far. EUS had an additional advantage over MRI by being able to obtain tissue sample during the same examination. Several questions remain unanswered at this time regarding the age to begin screening, frequency of screening, management of asymptomatic pancreatic lesions detected on screening, timing of resection, and extent of surgery and impact of screening on survival. Novel techniques such as needle-based confocal laser endomicroscopy (nCLE), along with biomarkers, may be helpful to identify pancreatic lesions with more aggressive malignant potential. Further studies will hopefully lead to the development of strategies combining EUS with other technological/biological advancements that will be cost-effective and have an impact on survival. PMID:26879161

  13. The effects of fatty deposits on the accuracy of the Fibroscan® liver transient elastography ultrasound system

    NASA Astrophysics Data System (ADS)

    Cournane, S.; Browne, J. E.; Fagan, A. J.

    2012-06-01

    A new generation of ultrasound transient elastography (TE) systems have emerged which exploit the well-known correlation between the liver's pathological and mechanical properties through measurements of the Young's elastic modulus; however, little work has been carried out to examine the effect that fatty deposits may have on the TE measurement accuracy. An investigation was carried out on the effects on the measurement accuracy of a TE ultrasound system, the Fibroscan®, caused by overlaying fat layers of varying thickness on healthy liver-mimicking phantoms, simulating in vivo conditions for obese patients. Furthermore, a steatosis effect similar to that in non-alcoholic fatty liver disease (NAFLD) and alcoholic liver disease (ALD) was simulated to investigate its effect on the TE system. A range of novel elastography fat-mimicking materials were developed using 6-10 wt% poly(vinyl alcohol) cryogel capable of achieving a range of acoustic velocities (1482-1530 m s-1) and attenuation coefficients (0.4-1 dB MHz-1 cm-1) for simulating different liver states. Laboratory-based acoustic velocities and attenuation coefficients were measured while the Young's modulus was established through a gold standard compression testing method. A significant variation of the Young's elastic modulus was measured in healthy phantoms with overlaying fat layers of thicknesses exceeding 45 mm, impinging on the scanners region of interest, overestimating the compression tested values by up to 11 kPa in some cases. Furthermore, Fibroscan® measurements of the steatosis phantoms showed a consistent overestimation (˜54%), which strongly suggests that the speed of sound mismatch between that of liver tissue and that assumed by the scanner is responsible for the high clinical cut-offs established in the case of ALD and NAFLD.

  14. Fabrication and Performance of a Miniaturized and Integrated Endoscope Ultrasound Convex Array for Digestive Tract Imaging.

    PubMed

    Peng, Jue; Peng, Xiaojian; Tang, Hu; Li, Xiaozhen; Chen, Ruimin; Li, Yang; Wang, Tianfu; Chen, Siping; Shung, Koping; Zhou, Qifa

    2017-04-24

    This work presents the design, fabrication and testing of a miniaturized and integrated ultrasound endoscope for use as an in situ digestive diagnostic device to facilitate real-time ultrasound guidance of intervention treatments. We designed an optimal structure to integrate an auto-focus 5-megapixel camera module with an 8-MHz, 64-element curvilinear ultrasonic array in one miniaturized package. A novel three-axis auto-focusing voice coil motor (VCM) was designed and manufactured for the camera module to move the lens position for auto-focusing and to adjust the lens tilt. The results showed that the array had a center frequency of 8.09 MHz and a -6-dB fractional bandwidth of 83%. At the center frequency, the two-way insertion loss was 40.6 dB. Endoscopic ultrasound imaging demonstrated satisfactory performance for imaging an anthropomorphic phantom of the esophagus. By slightly adjusting the tilt angle of the optical axis of the lens, the optical image captured by the auto-focusing lens obtained improved definition regardless of changes in the view angle of the camera with respect to the objects being captured. The integrated convex ultrasound endoscope, possessing minimal size, improved optical imaging definition, and good ultrasound imaging performance, can become a useful tool in digestive tract imaging. The miniaturized and integrated convex ultrasound endoscope can facilitate real-time ultrasound intervention guidance, reducing risks associated with the operation.

  15. Ultrasound strain elastography in assessment of cortical mechanical behavior in acute renal vein occlusion: in vivo animal model.

    PubMed

    Gao, Jing; He, Wen; Cheng, Ling-Gang; Li, Xiao-Ya; Zhang, Xiou-Ru; Juluru, Krishna; Al Khori, Noor; Coya, Adrienne; Min, Robert

    2015-01-01

    To assess the correlation of quantitative ultrasound strain parameters with the severity of cortical edema in renal vein occlusion, we prospectively performed ultrasound strain elastography on a canine acute renal vein occlusion model prior to and following 10, 20, and 40min of renal vein ligation. Strain and strain relaxation time representing the deformation and relaxation of the renal cortices and reference soft tissue were produced by the external compression with the ultrasound transducer and estimated using commercially available 2-D speckle tracking software. Cortical thickness was additionally measured. Repeated-measures analysis of variance was used to examine the difference in cortical thickness, strain ratio (mean cortical strain divided by mean reference tissue strain), and strain relaxation time ratio (cortical relaxation time divided by reference tissue relaxation time) prior to and after renal vein ligation. Pearson's correlation coefficient was applied to test the relationship between strain parameters and the time of the renal vein ligation. There was a strong positive correlation between the duration of renal vein ligation and strain (R(2)=0.97) and strain relaxation time (R(2)=0.98) ratios. Significant differences in strain and strain relaxation time ratios were found at all measured timepoints (all P≪.001). Cortical thickness, however, showed no significant difference between timepoints (P=.065). Our result suggest that strain and strain relaxation time ratios may be used as quantitative markers for the assessment of the renal cortical mechanical behavior in subclinical acute renal vein occlusion.

  16. Noninvasive assessment of the activity of the shoulder girdle muscles using ultrasound real-time tissue elastography.

    PubMed

    Ishikawa, Hiroaki; Muraki, Takayuki; Sekiguchi, Yusuke; Ishijima, Takahiro; Morise, Shuhei; Yamamoto, Nobuyuki; Itoi, Eiji; Izumi, Shin-Ichi

    2015-10-01

    The purpose of this study was to clarify whether the activity of the shoulder girdle muscles could be estimated by measuring the elasticity of these muscles under several levels of muscle contraction through ultrasound real-time tissue elastography (RTE). Ten healthy men performed submaximal voluntary contractions (MVC) in each manual muscle testing position for the middle deltoid, upper trapezius, supraspinatus, levator scapulae, and rhomboid major. The elasticity of these muscles was measured using ultrasound RTE during the task. The strain ratio of the muscle to an acoustic coupler was calculated as an assessment index of the muscle elasticity. Higher strain ratio values imply lower elasticity. In addition, the electromyographic activity was recorded from surface electrodes attached only to the middle deltoid and upper trapezius. The strain ratios were negatively correlated with the normalized root mean square values for the middle deltoid (r=-0.659, p<0.001) and upper trapezius (r=-0.554, p<0.001). The strain ratios of all the muscles decreased with an increase from 10% MVC force to 30% MVC force. Ultrasound RTE may be useful for noninvasively assessing the activity of the shoulder girdle muscles at certain shoulder positions with low levels of muscle contraction. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Comb-push ultrasound shear elastography (CUSE): a novel method for two-dimensional shear elasticity imaging of soft tissues.

    PubMed

    Song, Pengfei; Zhao, Heng; Manduca, Armando; Urban, Matthew W; Greenleaf, James F; Chen, Shigao

    2012-09-01

    Fast and accurate tissue elasticity imaging is essential in studying dynamic tissue mechanical properties. Various ultrasound shear elasticity imaging techniques have been developed in the last two decades. However, to reconstruct a full field-of-view 2-D shear elasticity map, multiple data acquisitions are typically required. In this paper, a novel shear elasticity imaging technique, comb-push ultrasound shear elastography (CUSE), is introduced in which only one rapid data acquisition (less than 35 ms) is needed to reconstruct a full field-of-view 2-D shear wave speed map (40 × 38 mm). Multiple unfocused ultrasound beams arranged in a comb pattern (comb-push) are used to generate shear waves. A directional filter is then applied upon the shear wave field to extract the left-to-right (LR) and right-to-left (RL) propagating shear waves. Local shear wave speed is recovered using a time-of-flight method based on both LR and RL waves. Finally, a 2-D shear wave speed map is reconstructed by combining the LR and RL speed maps. Smooth and accurate shear wave speed maps are reconstructed using the proposed CUSE method in two calibrated homogeneous phantoms with different moduli. Inclusion phantom experiments demonstrate that CUSE is capable of providing good contrast (contrast-to-noise ratio ≥ 25 dB) between the inclusion and background without artifacts and is insensitive to inclusion positions. Safety measurements demonstrate that all regulated parameters of the ultrasound output level used in CUSE sequence are well below the FDA limits for diagnostic ultrasound.

  18. [Reversal of portal blood flow in cirrhosis. Clinical, endoscopic and ultrasound endoscopic correlations in 72 patients].

    PubMed

    Letard, J C; Boustière, C; Romy, P; Jouffre, C; Patouillard, B; Etaix, J P; Barthélémy, C; Veyret, C; Audigier, J C

    1993-01-01

    From January to December 1991, the portal venous system was evaluated by Doppler ultrasonography in 72 patients with liver cirrhosis. The objectives of this study were to evaluate the prevalence of spontaneous reversal of blood flow in the portal vein and to assess the relationship between Doppler ultrasound investigation and clinical, biochemical, endoscopic (70 patients), and endosonographic (44 patients) features. Reversed flow was quite frequent (alternating: 17%, permanent: 22%) and its prevalence did not differ in relation to age, sex, serum gammaglobulin concentration and Child-Pugh class. In patients with reversed portal venous flow, the prevalence of hepatic encephalopathy was higher (39% vs 13.5%, P < 0.05), but the prevalence of esophageal or gastric varices was not related to that pattern. Endosonography detected gastric wall abnormalities in a higher proportion of patients with reversed portal flow than in patients without it (P < 0.05). This study suggests that reversal of flow in the portal vein could play a role in the development of the gastric wall abnormalities in liver cirrhosis, which are detected by endosonography but not by endoscopy.

  19. Quantification of dry needling and posture effects on myofascial trigger points using ultrasound shear-wave elastography.

    PubMed

    Maher, Ruth M; Hayes, Dawn M; Shinohara, Minoru

    2013-11-01

    To determine (1) whether the shear modulus in upper trapezius muscle myofascial trigger points (MTrPs) reduces acutely after dry needling (DN), and (2) whether a change in posture from sitting to prone affects the shear modulus. Ultrasound images were acquired in B mode with a linear transducer oriented in the transverse plane, followed by performance of shear-wave elastography (SWE) before and after DN and while sitting and prone. University. Women (N=7; mean age ± SD, 46±17y) with palpable MTrPs were recruited. All participants were dry needled in the prone position using solid filament needles that were inserted and manipulated inside the MTrPs. SWE was performed before and after DN in the sitting and prone positions. MTrPs were evaluated by shear modulus using SWE. Palpable reductions in stiffness were noted after DN and in the prone position. These changes were apparent in the shear modulus map obtained with ultrasound SWE. With significant main effects, the shear modulus reduced from before to after DN (P<.01) and from the sitting to the prone position (P<.05). No significant interaction effect between time and posture was observed. The shear modulus measured with ultrasound SWE reduced after DN and in the prone position compared with sitting, in agreement with reductions in palpable stiffness. These findings suggest that DN and posture have significant effects on the shear modulus of MTrPs, and that shear modulus measurement with ultrasound SWE may be sensitive enough to detect these effects. Copyright © 2013 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

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

    PubMed Central

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

    2017-01-01

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

  1. Ultrasound Elastography Combined With BI-RADS-US Classification System: Is It Helpful for the Diagnostic Performance of Conventional Ultrasonography?

    PubMed

    Hao, Shao-Yun; Jiang, Qiong-Chao; Zhong, Wen-Jing; Zhao, Xin-Bao; Yao, Ji-Yi; Li, Lu-Jing; Luo, Bao-Ming; Ou, Bing; Zhi, Hui

    2016-06-01

    To evaluate the additive diagnostic performance of ultrasound elastography (UE) to ultrasound (US) with the 2003 or 2013 Breast Imaging Reporting and Data System (BI-RADS)-US classification systems for the differentiation of benign and malignant breast lesions. From June 2010 to December 2012, 738 women with 770 breast lesions were recruited into this retrospective study. Breast lesions were evaluated separately by US, UE, and both. US assessment was based on the 2003 or 2013 BI-RADS-US, and UE assessment was based on a previously reported 5-point scale. Diagnostic performance of US, UE, and both was compared. Before category 4 lesions were subdivided, the area under the receiver operating characteristic curve (AUC) for US, UE, and both were, respectively, 0.735, 0.877, 0.878 (P < .01). When subcategories of 4 lesions were considered, the AUC for US, UE, and both were, respectively, 0.865, 0.877, and 0.883 (P > .05). Adding UE to analysis of 4A lesions can decrease the percentages of malignancy to 2.56%. When the 2003 BI-RADS was considered, UE could give US some help in differentiating breast lesions. However, when the 2013 BI-RADS was considered, UE gave little help to US, although it reduced unnecessary biopsies of benign category 4A lesions. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Monitoring Radiofrequency Ablation Using Ultrasound Envelope Statistics and Shear Wave Elastography in the Periablation Period: An In Vitro Feasibility Study

    PubMed Central

    Tsui, Po-Hsiang; Wang, Chiao-Yin; Zhou, Zhuhuang; Wan, Yung-Liang

    2016-01-01

    Radiofrequency ablation (RFA) is a minimally invasive method for treating tumors. Shear wave elastography (SWE) has been widely applied in evaluating tissue stiffness and final ablation size after RFA. However, the usefulness of periablation SWE imaging in assessing RFA remains unclear. Therefore, this study investigated the correlation between periablation SWE imaging and final ablation size. An in vitro porcine liver model was used for experimental validation (n = 36). During RFA with a power of 50 W, SWE images were collected using a clinical ultrasound system. To evaluate the effects of tissue temperature and gas bubbles during RFA, changes in the ablation temperature were recorded, and image echo patterns were measured using B-mode and ultrasound statistical parametric images. After RFA, the gross pathology of each tissue sample was compared with the region of change in the corresponding periablation SWE image. The experimental results showed that the tissue temperature at the ablation site varied between 70°C and 100°C. Hyperechoic regions and changes were observed in the echo amplitude distribution induced by gas bubbles. Under this condition, the confounding effects (including the temperature increase, tissue stiffness increase, and presence of gas bubbles) resulted in artifacts in the periablation SWE images, and the corresponding region correlated with the estimated final ablation size obtained from the gross pathology (r = 0.8). The findings confirm the feasibility of using periablation SWE imaging in assessing RFA. PMID:27603012

  3. [Strategies for screening for pancreatic adenocarcinoma in high-risk patients: the place of endoscopic ultrasound].

    PubMed

    Béchade, Dominique

    2011-03-01

    Screening high-risk individuals with imaging tests, such endoscopic ultrasound and computed tomography, can lead to the detection and treatment of predominantly asymptomatic premalignant lesions. These pancreatic lesions consist of resectable, mostly branch-type non invasive intraductal papillary mucinous neoplasms. Endoscopic ultrasound features of chronic pancreatitis are highly prevalent in high-risk individuals and these directly correlate with multifocal lobulocentric parenchymal atrophy due to pancreatic intraepithelial neoplasia. Long-term, multi-prospective studies are needed to determine if screening for early pancreatic adenocarcinoma and timely intervention results in decreased pancreatic cancer incidence and mortality in high-risk individuals.

  4. Trainee anaesthetist diagnosis of intraneural injection-a study comparing B-mode ultrasound with the fusion of B-mode and elastography in the soft embalmed Thiel cadaver model.

    PubMed

    Munirama, S; Zealley, K; Schwab, A; Columb, M; Corner, G A; Eisma, R; McLeod, G A

    2016-12-01

    The incidence of intraneural injection during trainee anaesthetist ultrasound guided nerve block varies between 16% in experts and up to 35% in trainees. We hypothesized that elastography, an ultrasound-based technology that presents colour images of tissue strain, had the potential to improve trainee diagnosis of intraneural injection during UGRA, when integrated with B-Mode ultrasound onto a single image. We recorded 40 median nerve blocks randomly allocated to 0.25 ml, 0.5 ml, 1 ml volumes to five sites, on both arms of two soft embalmed cadavers, using a dedicated B-Mode ultrasound and elastography transducer. We wrote software to fuse elastogram and B-Mode videos, then asked 20 trainee anaesthetists whether injection was intraneural or extraneural when seeing B-Mode videos, adjacent B-Mode and elastogram videos, fusion elastography videos or repeated B-Mode ultrasound videos. Fusion elastography improved the diagnosis of intraneural injection compared with B-Mode ultrasound, Diagnostic Odds Ratio (DOR) (95%CI) 21.7 (14.5 - 33.3) vs DOR 7.4 (5.2 - 10.6), P < 0.001. Compared with extraneural injection, intraneural injection was identified on fusion elastography as a distinct, brighter translucent image, geometric ratio 0.33 (95%CI: 0.16 - 0.49) P < 0.001. Fusion elastography was associated with greater trainee diagnostic confidence, OR (95%CI) 1.89 (1.69 - 2.11), P < 0.001, and an improvement in reliability, Kappa 0.60 (0.55 - 0.66). Fusion elastography improved the accuracy, reliability and confidence of trainee anaesthetist diagnosis of intraneural injection. © The Author 2016. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  5. DOES ENDOSCOPIC ULTRASOUND IMPROVE DETECTION OF LOCALLY RECURRENT ANAL SQUAMOUS CELL CANCER?

    PubMed Central

    Peterson, Carrie Y.; Weiser, Martin R.; Paty, Philip B.; Guillem, Jose G.; Nash, Garrett M.; Garcia-Aguilar, Julio; Patil, Sujata; Temple, Larissa K.

    2015-01-01

    Background Evaluating patients for recurrent anal cancer after primary treatment can be difficult due to distorted anatomy and scarring. Many institutions incorporate endoscopic ultrasound to improve detection, but the effectiveness is unknown. Objective To compare the effectiveness of digital rectal exam and endoscopic ultrasound during routine follow-up of anal cancer patients in detecting locally recurrent disease. Design Retrospective, single-institution review Settings Oncologic tertiary referral center Patients 175 patients with nonmetastatic anal squamous cell cancer without persistent disease after primary chemoradiotherapy who had at least one post-treatment ultrasound and examination by a colorectal surgeon. Main Outcome Measures First modality to detect local recurrence, concordance, crude cancer detection rate, sensitivity, specificity, and predictive value. Results 855 endoscopic ultrasounds and 873 digital rectal exams were performed during 35 months median follow-up. Overall, ultrasound detected 7 (0.8%) mesorectal and 32 (3.7%) anal canal abnormalities; digital exam detected 69 (7.9%) anal canal abnormalities. Locally recurrent disease was found on biopsy in 8 patients, all detected first or only with digital exam. Four patients did not have an ultrasound at the time of diagnosis of recurrence. The concordance of ultrasound and digital exam in detecting recurrent disease was fair at 0.37 (SE 0.08, 95% CI 0.21-0.54) and there was no difference in crude cancer detection rate, sensitivity, specificity, and negative or positive predictive values. Limitations The heterogeneity of follow-up timing and exams is not standardized in this study but is reflective of general practice. Conclusions Endoscopic ultrasound did not provide any advantage over digital rectal examination in identifying locally recurrent anal cancer, and should not be recommended for routine surveillance. PMID:25585077

  6. Building a virtual simulation platform for quasistatic breast ultrasound elastography using open source software: A preliminary investigation.

    PubMed

    Wang, Yu; Helminen, Emily; Jiang, Jingfeng

    2015-09-01

    Quasistatic ultrasound elastography (QUE) is being used to augment in vivo characterization of breast lesions. Results from early clinical trials indicated that there was a lack of confidence in image interpretation. Such confidence can only be gained through rigorous imaging tests using complex, heterogeneous but known media. The objective of this study is to build a virtual breast QUE simulation platform in the public domain that can be used not only for innovative QUE research but also for rigorous imaging tests. The main thrust of this work is to streamline biomedical ultrasound simulations by leveraging existing open source software packages including Field II (ultrasound simulator), VTK (geometrical visualization and processing), FEBio [finite element (FE) analysis], and Tetgen (mesh generator). However, integration of these open source packages is nontrivial and requires interdisciplinary knowledge. In the first step, a virtual breast model containing complex anatomical geometries was created through a novel combination of image-based landmark structures and randomly distributed (small) structures. Image-based landmark structures were based on data from the NIH Visible Human Project. Subsequently, an unstructured FE-mesh was created by Tetgen. In the second step, randomly positioned point scatterers were placed within the meshed breast model through an octree-based algorithm to make a virtual breast ultrasound phantom. In the third step, an ultrasound simulator (Field II) was used to interrogate the virtual breast phantom to obtain simulated ultrasound echo data. Of note, tissue deformation generated using a FE-simulator (FEBio) was the basis of deforming the original virtual breast phantom in order to obtain the postdeformation breast phantom for subsequent ultrasound simulations. Using the procedures described above, a full cycle of QUE simulations involving complex and highly heterogeneous virtual breast phantoms can be accomplished for the first time

  7. Building a virtual simulation platform for quasistatic breast ultrasound elastography using open source software: A preliminary investigation

    PubMed Central

    Wang, Yu; Helminen, Emily; Jiang, Jingfeng

    2015-01-01

    Purpose: Quasistatic ultrasound elastography (QUE) is being used to augment in vivo characterization of breast lesions. Results from early clinical trials indicated that there was a lack of confidence in image interpretation. Such confidence can only be gained through rigorous imaging tests using complex, heterogeneous but known media. The objective of this study is to build a virtual breast QUE simulation platform in the public domain that can be used not only for innovative QUE research but also for rigorous imaging tests. Methods: The main thrust of this work is to streamline biomedical ultrasound simulations by leveraging existing open source software packages including Field II (ultrasound simulator), VTK (geometrical visualization and processing), FEBio [finite element (FE) analysis], and Tetgen (mesh generator). However, integration of these open source packages is nontrivial and requires interdisciplinary knowledge. In the first step, a virtual breast model containing complex anatomical geometries was created through a novel combination of image-based landmark structures and randomly distributed (small) structures. Image-based landmark structures were based on data from the NIH Visible Human Project. Subsequently, an unstructured FE-mesh was created by Tetgen. In the second step, randomly positioned point scatterers were placed within the meshed breast model through an octree-based algorithm to make a virtual breast ultrasound phantom. In the third step, an ultrasound simulator (Field II) was used to interrogate the virtual breast phantom to obtain simulated ultrasound echo data. Of note, tissue deformation generated using a FE-simulator (FEBio) was the basis of deforming the original virtual breast phantom in order to obtain the postdeformation breast phantom for subsequent ultrasound simulations. Using the procedures described above, a full cycle of QUE simulations involving complex and highly heterogeneous virtual breast phantoms can be accomplished for

  8. Accuracy of Tumor Sizing in Breast Cancer: A Comparison of Strain Elastography, 3-D Ultrasound and Conventional B-Mode Ultrasound with and without Compound Imaging.

    PubMed

    Stachs, Angrit; Pandjaitan, Alexander; Martin, Annett; Stubert, Johannes; Hartmann, Steffi; Gerber, Bernd; Glass, Änne

    2016-12-01

    The objective of this study was to compare the accuracy of strain elastography (SE), 3-D ultrasound (US), B-mode US with compound imaging (CI) and B-mode US without compound imaging for lesion sizing in breast cancer. The prospective study included 93 patients with invasive breast cancer. The largest tumor diameters measured by B-mode US, B-mode US with CI, SE and 3-D US were compared in Bland-Altman plots versus pathology as reference. A general linear model repeated measures (GLM Rep) was applied to investigate factors influencing tumor sizing. All methods underestimated pathologic size, with SE (-0.08 ± 7.7 mm) and 3-D US (-1.4 ± 6.5 mm) having the smallest mean differences from pathology. Bland-Altman plots revealed that B-mode US, B-mode US with CI and 3-D US systematically underestimated large tumor sizes, and only SE was technically comparable to pathology. The study indicates that sonographic underestimation of tumor size occurs mainly in tumors >20 mm; in this subgroup, SE is superior to other ultrasound methods.

  9. Treatment of a Splenic Artery Pseudoaneurysm by Endoscopic Ultrasound-Guided Thrombin Injection

    SciTech Connect

    Robinson, Mark Richards, Dafydd; Carr, Nicholas

    2007-06-15

    We present a case of a splenic artery pseudoaneurysm secondary to pancreatitis that was successfully treated by transgastric injection of thrombin under endoscopic ultrasound guidance. There has been no recurrence on follow-up CT angiography, and thus complex surgery or endovascular intervention has been avoided.

  10. Computationally-efficient optical coherence elastography to assess degenerative osteoarthritis based on ultrasound-induced fringe washout (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Tong, Minh Q.; Hasan, M. Monirul; Gregory, Patrick D.; Shah, Jasmine; Park, B. Hyle; Hirota, Koji; Liu, Junze; Choi, Andy; Low, Karen; Nam, Jin

    2017-02-01

    We demonstrate a computationally-efficient optical coherence elastography (OCE) method based on fringe washout. By introducing ultrasound in alternating depth profile, we can obtain information on the mechanical properties of a sample within acquisition of a single image. This can be achieved by simply comparing the intensity in adjacent depth profiles in order to quantify the degree of fringe washout. Phantom agar samples with various densities were measured and quantified by our OCE technique, the correlation to Young's modulus measurement by atomic force micrscopy (AFM) were observed. Knee cartilage samples of monoiodo acetate-induced arthiritis (MIA) rat models were utilized to replicate cartilage damages where our proposed OCE technique along with intensity and birefringence analyses and AFM measurements were applied. The results indicate that our OCE technique shows a correlation to the techniques as polarization-sensitive OCT, AFM Young's modulus measurements and histology were promising. Our OCE is applicable to any of existing OCT systems and demonstrated to be computationally-efficient.

  11. The difference in passive tension applied to the muscles composing the hamstrings - Comparison among muscles using ultrasound shear wave elastography.

    PubMed

    Nakamura, Masatoshi; Hasegawa, Satoshi; Umegaki, Hiroki; Nishishita, Satoru; Kobayashi, Takuya; Fujita, Kosuke; Tanaka, Hiroki; Ibuki, Satoko; Ichihashi, Noriaki

    2016-08-01

    Hamstring muscle strain is one of the most common injuries in sports. Therefore, to investigate the factors influencing hamstring strain, the differences in passive tension applied to the hamstring muscles at the same knee and hip positions as during terminal swing phase would be useful information. In addition, passive tension applied to the hamstrings could change with anterior or posterior tilt of the pelvis. The aims of this study were to investigate the difference in passive tension applied to the individual muscles composing the hamstrings during passive elongation, and to investigate the effect of pelvic position on passive tension. Fifteen healthy men volunteered for this study. The subject lay supine with the angle of the trunk axis to the femur of their dominant leg at 70° and the knee angle of the dominant leg fixed at 30° flexion. In three pelvic positions ("Non-Tilt", "Anterior-Tilt" and "Posterior-Tilt"), the shear elastic modulus of each muscle composing the hamstrings (semitendinosus, semimembranosus, and biceps femoris) was measured using an ultrasound shear wave elastography. The shear elastic modulus of semimembranosus was significantly higher than the others. Shear elastic modulus of the hamstrings in Anterior-Tilt was significantly higher than in Posterior-Tilt. Passive tension applied to semimembranosus is higher than the other muscles when the hamstring muscle is passively elongated, and passive tension applied to the hamstrings increases with anterior tilt of the pelvis. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Acute effect of static stretching on passive stiffness of the human gastrocnemius fascicle measured by ultrasound shear wave elastography.

    PubMed

    Hirata, Kosuke; Kanehisa, Hiroaki; Miyamoto, Naokazu

    2017-03-01

    Passive muscle stiffness and muscle architecture at a given joint angle, as well as slack angle of the muscle have been shown to change after an acute bout of stretching. However, it remains unclear whether passive muscle stiffness at a given fascicle length is reduced after stretching. We aimed to elucidate the acute effect of static stretching on the passive fascicle stiffness using ultrasound shear wave elastography. Shear modulus, fascicle length, and slack angle of the medial gastrocnemius (MG) as well as passive plantar flexion torque during passive dorsiflexion were measured before and after a 5-min static stretching in 14 healthy males. After stretching, passive torques were significantly reduced at >50% of range of motion (ROM). Shear modulus at a given fascicle length was significantly reduced at >80% of the change in fascicle length during passive dorsiflexion. Slack angle of MG was observed at the middle part of ROM and significantly shifted toward more dorsiflexed position after stretching. The present study showed the significant effectiveness of static stretching on the passive fascicle stiffness. Furthermore, the present results suggest that both the shift in slack angle and the reduction in passive fascicle stiffness contribute to produce the change in passive torque-joint angle relationship during passive dorsiflexion. Notably, the contribution of the reduced passive fascicle stiffness to the decrease in passive torque is substantial over the latter part of ROM.

  13. A pilot study evaluating real-time shear wave ultrasound elastography of miscellaneous non-nodal neck masses in a routine head and neck ultrasound clinic.

    PubMed

    Bhatia, Kunwar S S; Yuen, Edmund H Y; Cho, Carmen C M; Tong, Cina S L; Lee, Yolanda Y P; Ahuja, Anil T

    2012-06-01

    A pilot study was performed to evaluate shear wave ultrasound elastography (SWE) for miscellaneous non-nodal/salivary/thyroid neck lesions. Forty-six lesions undergoing conventional sonography also underwent SWE. Elastic moduli from the stiffest areas in lesions were correlated with diagnosis. Forty lesions were benign (9 lipomas, 8 lymphatic/venous vascular malformations, 7 thyroglossal duct cysts, 4 branchial cleft cysts, 4 abscesses/phlegmons, 3 neurogenic tumors and 1 each of paraganglioma, sebaceous cyst, pseudotumor, hypertrophic scar, ranula) and 6 were malignant (1 malignant fibrous histiocytoma, 2 primary squamous cell carcinomas and 3 intramuscular metastases [2 squamous cell carcinomas, 1 malignant melanoma]).Median stiffness of malignant lesions (226.4 kPa, range 55.6 to 300.0) was higher than benign lesions (28.3 kPa, range 4.0 to 300.0) (p < 0.001). SWE cut-off with highest accuracy (174.4 kPa) achieved 83.3% sensitivity and 97.5% specificity, and the cut-off with 100% sensitivity (55.6 kPa) achieved 75% specificity. All malignant lesions were suspected on conventional sonography. The preliminary data indicate that SWE is feasible for miscellaneous neck lesions. SWE would not have altered management in terms of detecting undisclosed malignancies, although as a quantitative technique, it may increase the diagnostic confidence of less experienced operators performing head and neck ultrasound. Copyright © 2012 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  14. A case report of intraoperative endoscopic ultrasound during robotic assisted Heller myotomy for severe esophageal achalasia.

    PubMed

    Abdel Khalek, Mohamed; Abbas, Abbas; Joshi, Virendra; Hariri, Nizar; Kandil, Emad

    2011-01-01

    Esophageal achalasia is the best described primary esophageal motility disorder. Endoscopic ultrasound (EUS) is considered a useful adjunct for grading and establishing the prognosis of these patients. Recent experience using Da Vinci robotic assisted myotomy has demonstrated that this is a safe and effective approach of treatment. The benefit of magnification and three dimensional imaging helps prevent esophageal perforation and identify residual circular muscle fibers. This paper reports the relative efficacy and safety of intraoperative ultrasound during robotic assisted myotomy in a patient with severe achalasia. Intraoperative esophageal endoscopic ultrasound is a safe technique that may improve the success rate of surgery by confirming the adequacy of myotomy, thereby decreasing the likelihood of recurrent symptoms.

  15. Feasibility and reliability of quantifying passive muscle stiffness in young children by using shear wave ultrasound elastography.

    PubMed

    Brandenburg, Joline E; Eby, Sarah F; Song, Pengfei; Zhao, Heng; Landry, Bradford W; Kingsley-Berg, Shirley; Bamlet, William R; Chen, Shigao; Sieck, Gary C; An, Kai-Nan

    2015-04-01

    The purpose of this study was to investigate the feasibility and reliability of passive muscle stiffness measurements in children by shear wave ultrasound elastography. We conducted a prospective cross-sectional study quantifying the passive stiffness of bilateral lateral gastrocnemius muscles during passive stretching in 20 typically developing children (age range, 2.0-12.6 years). Data collected included passive stiffness of the lateral gastrocnemius muscle (shear modulus in kilopascals) at 4 positions of progressive passive foot dorsiflexion, demographic characteristics of the participants, and comparison of demographic characteristics with the shear modulus. Passive stiffness increased with increasing stretching (mean [SD] range of stiffness, 7.1 [2.0] to 36.2 [22.0] kPa). For all 4 foot positions, no significant difference was found between right and left legs (range, P = .42 to P = .98) or between the sexes (range, P = .28 to P > .99). No correlation of passive muscle stiffness with age, body mass index, or ankle range of motion was found. The reliability of measurements was good to excellent (mean [95% confidence interval] range of reliability, 0.67 [0.44-0.83] to 0.80 [0.63-0.90]). Measurements of passive stiffness of the lateral gastrocnemius muscle are feasible and reliable in children as young as 2 years. Because this study found no significant difference between sex and the side tested in this age group, future studies involving children of this age range may not need to be stratified on the basis of these parameters. Defining normal passive muscle stiffness in children is critical for identifying and understanding the implications of abnormal passive muscle stiffness in children with neuromuscular disorders. © 2015 by the American Institute of Ultrasound in Medicine.

  16. Ultrasound shear wave elastography in assessment of muscle stiffness in patients with Parkinson's disease: a primary observation.

    PubMed

    Du, Li-Juan; He, Wen; Cheng, Ling-Gang; Li, Shuo; Pan, Yue-Song; Gao, Jing

    The aim of this study was to assess the capability of ultrasound shear wave elastography (SWE) in evaluating the muscle stiffness in patients with Parkinson's diseases (PD). Ultrasound SWE of the longitudinal biceps brachii was performed on 46 patients with PD and 31 healthy controls from May 2013 to October 2013. The stiffness of the biceps brachii muscles measured with quantitative Young's modulus (kPa) was compared between the remarkably symptomatic arms and mildly symptomatic arms in the PD and between PD and controls with unpaired t test. The correlation between the Young's modulus of the biceps brachii measured by SWE and motion scores assessed by unified Parkinson's disease rating scale (UPDRS) part III was analyzed by Pearson's correlation coefficient. The reliability of SWE in assessment of biceps brachii stiffness was tested using intraclass correlation coefficient (ICC). The mean Young's modulus of biceps brachii in remarkably symptomatic arms, mildly symptomatic arms, and healthy controls was 59.94±20.91 kPa, 47.77±24.00 kPa, and 24.28±5.09 kPa, respectively. A significant difference in Young's modulus of biceps brachii was found between healthy controls and all PD patients (all P<.05); however, it was not between remarkably symptomatic and mildly symptomatic arms. A positive linear correlation was found between the Young's modulus of the biceps brachii and the motion score by UPDRS in patients with PD (r=0.646, P=.000). The ICC for interobserver and intraobserver variation in measuring Young's modulus of the biceps brachii with SWE was 0.74 (95% confidence interval 0.68-0.78) and 0.78 (95% confidence interval 0.75-0.82), respectively. SWE of the biceps brachii can be used as a quantitative assessment of muscle stiffness in the patients with PD. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Cardiac shear-wave elastography using a transesophageal transducer: application to the mapping of thermal lesions in ultrasound transesophageal cardiac ablation

    NASA Astrophysics Data System (ADS)

    Kwiecinski, Wojciech; Bessière, Francis; Constanciel Colas, Elodie; Apoutou N'Djin, W.; Tanter, Mickaël; Lafon, Cyril; Pernot, Mathieu

    2015-10-01

    Heart rhythm disorders, such as atrial fibrillation or ventricular tachycardia can be treated by catheter-based thermal ablation. However, clinically available systems based on radio-frequency or cryothermal ablation suffer from limited energy penetration and the lack of lesion’s extent monitoring. An ultrasound-guided transesophageal device has recently successfully been used to perform High-Intensity Focused Ultrasound (HIFU) ablation in targeted regions of the heart in vivo. In this study we investigate the feasibility of a dual therapy and imaging approach on the same transesophageal device. We demonstrate in vivo that quantitative cardiac shear-wave elastography (SWE) can be performed with the device and we show on ex vivo samples that transesophageal SWE can map the extent of the HIFU lesions. First, SWE was validated with the transesophageal endoscope in one sheep in vivo. The stiffness of normal atrial and ventricular tissues has been assessed during the cardiac cycle (n=11 ) and mapped (n= 7 ). Second, HIFU ablation has been performed with the therapy-imaging transesophageal device in ex vivo chicken breast samples (n  =  3), then atrial (left, n= 2 ) and ventricular (left n=1 , right n=1 ) porcine heart tissues. SWE provided stiffness maps of the tissues before and after ablation. Areas of the lesions were obtained by tissue color change with gross pathology and compared to SWE. During the cardiac cycle stiffness varied from 0.5   ±   0.1 kPa to 6.0   ±   0.3 kPa in the atrium and from 1.3   ±   0.3 kPa to 13.5   ±   9.1 kPa in the ventricles. The thermal lesions were visible on all SWE maps performed after ablation. Shear modulus of the ablated zones increased to 16.3   ±   5.5 kPa (versus 4.4   ±   1.6 kPa before ablation) in the chicken breast, to 30.3   ±   10.3 kPa (versus 12.2   ±   4.3 kPa) in the atria and to 73.8   ±   13

  18. Cardiac shear-wave elastography using a transesophageal transducer: application to the mapping of thermal lesions in ultrasound transesophageal cardiac ablation.

    PubMed

    Kwiecinski, Wojciech; Bessière, Francis; Colas, Elodie Constanciel; N'Djin, W Apoutou; Tanter, Mickaël; Lafon, Cyril; Pernot, Mathieu

    2015-10-21

    Heart rhythm disorders, such as atrial fibrillation or ventricular tachycardia can be treated by catheter-based thermal ablation. However, clinically available systems based on radio-frequency or cryothermal ablation suffer from limited energy penetration and the lack of lesion's extent monitoring. An ultrasound-guided transesophageal device has recently successfully been used to perform High-Intensity Focused Ultrasound (HIFU) ablation in targeted regions of the heart in vivo. In this study we investigate the feasibility of a dual therapy and imaging approach on the same transesophageal device. We demonstrate in vivo that quantitative cardiac shear-wave elastography (SWE) can be performed with the device and we show on ex vivo samples that transesophageal SWE can map the extent of the HIFU lesions. First, SWE was validated with the transesophageal endoscope in one sheep in vivo. The stiffness of normal atrial and ventricular tissues has been assessed during the cardiac cycle (n = 11) and mapped (n = 7). Second, HIFU ablation has been performed with the therapy-imaging transesophageal device in ex vivo chicken breast samples (n  =  3), then atrial (left, n = 2) and ventricular (left n = 1, right n = 1) porcine heart tissues. SWE provided stiffness maps of the tissues before and after ablation. Areas of the lesions were obtained by tissue color change with gross pathology and compared to SWE. During the cardiac cycle stiffness varied from 0.5   ±   0.1 kPa to 6.0   ±   0.3 kPa in the atrium and from 1.3   ±   0.3 kPa to 13.5   ±   9.1 kPa in the ventricles. The thermal lesions were visible on all SWE maps performed after ablation. Shear modulus of the ablated zones increased to 16.3   ±   5.5 kPa (versus 4.4   ±   1.6 kPa before ablation) in the chicken breast, to 30.3   ±   10.3 kPa (versus 12.2   ±   4.3 kPa) in the atria and to 73.8

  19. Two-dimensional and shear wave elastography ultrasound: A reliable method to analyse spastic muscles?

    PubMed

    Mathevon, Laure; Michel, F; Aubry, S; Testa, R; Lapole, T; Arnaudeau, L F; Fernandez, B; Parratte, B; Calmels, P

    2017-05-31

    Few data exist on the feasibility and reliability of measuring muscular atrophy in 2 dimensions (2D) by ultrasonography (US) and elasticity with shear wave elastography (SWE) in spastic muscles. Fourteen patients with chronic stroke took part in 2 intersession reliability experiments performed with 1-week intervals between sessions. Pennation angle (PA), muscle thickness (MT), and shear elastic modulus (µ) were measured in spastic gastrocnemius medialis (GM) muscles at rest and at maximal passive stretching in paretic and nonparetic legs. On the paretic side, the coefficient of variation (CV) in GM was 6.30% for MT and 6.40% for PA at rest and was 7.53% and 8.26% for MT and PA, respectively, at maximal passive stretching. The reliability of the µ measurement was good only for GM at rest on the paretic side (CV = 9.86%). 2D US associated with SWE shows promise for assessing structural changes in muscles. With some methodological adaptations, this approach could help guide spasticity treatment. Muscle Nerve, 2017. © 2017 Wiley Periodicals, Inc.

  20. Ultrasound shear wave elastography and liver fibrosis: A Prospective Multicenter Study

    PubMed Central

    Sande, Joyce Anyona; Verjee, Suleman; Vinayak, Sudhir; Amersi, Farin; Ghesani, Munir

    2017-01-01

    AIM To assess the accuracy of shear wave elastography (SWE) alone and in combination with aminotransferase platelet ratio index (APRI) score in the staging of liver fibrosis. METHODS A multicenter prospective study was conducted to assess the accuracy of SWE (medians) and APRI to predict biopsy results. The analysis focused on distinguishing the different stages of liver disease, namely, F0 from F1-4, F0-1 from F2-4, F0-2 from F3-4 and F0-3 from F4; F0-F1 from F2-F4 being of primary interest. The area under the receiver operating characteristic (AUROC) curve was computed using logistic regression model. The role of age, gender and steatosis was also assessed. RESULTS SWE alone accurately distinguished F0-1 from F2-4 with a high probability. The AUROC using SWE alone was 0.91 compared to 0.78 for using the APRI score alone. The APRI score, when used in conjunction with SWE, did not make a significant contribution to the AUROC. SWE and steatosis were the only significant predictors that differentiated F0-1 from F2-4 with an AUROC of 0.944. CONCLUSION Our study validates the use of SWE in the diagnosis and staging of liver fibrosis. Furthermore, the probability of a correct diagnosis is significantly enhanced with the addition of steatosis as a prognostic factor. PMID:28105257

  1. Radiation force of ultrasound as shear wave source in microscopic magnetic resonance elastography

    NASA Astrophysics Data System (ADS)

    Othman, Shadi F.; Ozer, M. Bulent; Xu, Huihui; Royston, Thomas J.; Magin, Richard L.

    2005-09-01

    Microscopic magnetic resonance elastography (micro-MRE) is a high-resolution imaging technique for measuring the viscoelastic properties of small synthetic and biological samples. Taking MRE to the microscopic scale requires stronger static fields, stronger magnetic field gradients, higher performance RF coils, and more compact, higher frequency shear wave actuators. Prior work by our group has been conducted at 11.74 T. A needle attached to a vibrating cantilever beam was placed in contact with the surface of the sample to generate shear waves up to 800 Hz. At higher frequencies, the excited shear waves attenuate within an extremely short distance such that only a very small region in the vicinity of the actuator can be studied due to inherent dynamic range limitations. In principle, modulated focused radiation force of US should be able to create a localized shear wave source within the test sample at a distance from the US transducer, thereby enabling micro-MRE probing of the sample at very high frequencies (up to 5 kHz). A confocal US transducer was fabricated to create such a source within the working constraints of the micro-MRE system. Initial feasibility studies are reviewed in this presentation. [Research supported by NIH Grant No. EB004885-01.

  2. Utility of endoscopic ultrasound in the diagnosis and management of esophagogastric varices

    PubMed Central

    Wang, An-Jiang; Li, Bi-Min; Zheng, Xue-Lian; Shu, Xu; Zhu, Xuan

    2016-01-01

    Endoscopic ultrasound (EUS) has significantly improved our understanding of the complex vascular structural changes in patients with portal hypertension. At present, EUS is a useful diagnostic tool for the evaluation of esophagogastric varices (EGVs) and guidance of endoscopic therapy. Several studies have employed this new technique for the diagnosis and management of esophageal and gastric varices, respectively. In the present review, we have summarized the current status of EUS for the diagnosis and management of EGVs and clarified the clinical feasibility of this procedure. New indications for EUS can be developed in the future after adequate validation. PMID:27503152

  3. Forward-viewing endoscopic ultrasound-guided NOTES interventions: A study on peritoneoscopic potential

    PubMed Central

    Jeong, Seung Uk; Aizan, Hassanuddin; Song, Tae Jun; Seo, Dong Wan; Kim, Su-Hui; Park, Do Hyun; Lee, Sang Soo; Lee, Sung Koo; Kim, Myung-Hwan

    2013-01-01

    AIM: To evaluate the feasibility of diagnostic and therapeutic transgastric (TG) peritoneoscopic interventions with a forward-viewing endoscopic ultrasound (FV-EUS). METHODS: This prospective endoscopic experimental study used an animal model. Combined TG peritoneoscopic interventions and EUS examination of the intra-abdominal organs were performed using an FV-EUS on 10 animal models (1 porcine and 9 canine). The procedures carried out include EUS evaluation and endoscopic biopsy of intraperitoneal organs, EUS-guided fine needle aspiration (EUS-FNA), EUS-guided radiofrequency ablation (EUS-RFA), and argon plasma coagulation (APC) for hemostatic control. The animals were kept alive for 7 d, and then necropsy was performed to evaluate results and complications. RESULTS: In all 10 animals, TG peritoneoscopy, followed by endoscopic biopsy for the liver, spleen, abdominal wall, and omentum, was performed successfully. APC helped control minor bleeding. Visualization of intra-abdominal solid organs with real-time EUS was accomplished with ease. Intraperitoneal EUS-FNA was successfully performed on the liver, spleen, and kidney. Similarly, a successful outcome was achieved with EUS-RFA of the hepatic parenchyma. No adverse events were recorded during the study. CONCLUSION: Peritoneoscopic natural orifice transluminal endoscopic surgery (NOTES) interventions through FV-EUS were feasible in providing evaluation and performing endoscopic procedures. It promises potential as a platform for future EUS-based NOTES. PMID:24222961

  4. Evaluation of human muscle hardness after dynamic exercise with ultrasound real-time tissue elastography: a feasibility study.

    PubMed

    Yanagisawa, O; Niitsu, M; Kurihara, T; Fukubayashi, T

    2011-09-01

    To assess the feasibility of ultrasound real-time tissue elastography (RTE) for measuring exercise-induced changes in muscle hardness and to compare the findings of RTE with those of a tissue hardness meter for semi-quantitative assessment of the hardness of exercised muscles. Nine male participants performed an arm-curl exercise. RTE measurements were performed by manually applying repetitive compression with the transducer on the scan position before exercise, immediately after exercise, and at 30 min after exercise; strain ratios between muscle and a reference material (hydrogel) were calculated (muscle strain/material strain). A tissue hardness meter was also used to evaluate muscle hardness. The intraclass correlation coefficients (ICCs) for the three repeated measurements at each measurement time were calculated to evaluate the intra-observer reproducibility of each technique. Immediately after exercise, the strain ratio and the value obtained using the tissue hardness meter significantly decreased (from 1.65 to 1.35) and increased (from 51.8 to 54.3), respectively. Both parameters returned to their pre-exercise value 30 min after exercise. The ICCs of the RTE (and the ICCs of the muscle hardness meter) were 0.971 (0.816) before exercise, 0.939 (0.776) immediately after exercise, and 0.959 (0.882) at 30 min after exercise. Similar to the muscle hardness meter, RTE revealed the exercise-induced changes of muscle hardness semi-quantitatively. The intra-observer reproducibility of RTE was very high at each measurement time. These findings suggest that RTE is a clinically useful technique for assessing hardness of specific exercised muscles. Copyright © 2011 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  5. Non-invasive assessment of human multifidus muscle stiffness using ultrasound shear wave elastography: A feasibility study.

    PubMed

    Moreau, Baptiste; Vergari, Claudio; Gad, Hisham; Sandoz, Baptiste; Skalli, Wafa; Laporte, Sébastien

    2016-08-01

    There is a lack of numeric data for the mechanical characterization of spine muscles, especially in vivo data. The multifidus muscle is a major muscle for the stabilization of the spine and may be involved in the pathogenesis of chronic low back pain (LBP). Supersonic shear wave elastography (SWE) has not yet been used on back muscles. The purpose of this prospective study is to assess the feasibility of ultrasound SWE to measure the elastic modulus of lumbar multifidus muscle in a passive stretching posture and at rest with a repeatable and reproducible method. A total of 10 asymptotic subjects (aged 25.5 ± 2.2 years) participated, 4 females and 6 males. Three operators performed 6 measurements for each of the 2 postures on the right multifidus muscle at vertebral levels L2-L3 and L4-L5. Repeatability and reproducibility have been assessed according to ISO 5725 standard. Intra-class correlation coefficients (ICC) for intra- and inter-observer reliability were rated as both excellent [ICC=0.99 and ICC=0.95, respectively]. Reproducibility was 11% at L2-L3 level and 19% at L4-L5. In the passive stretching posture, shear modulus was significantly higher than at rest (µ < 0.05). This preliminary work enabled to validate the feasibility of measuring the shear modulus of the multifidus muscle with SWE. This kind of measurement could be easily introduces into clinical routine like for the medical follow-up of chronic LBP or scoliosis treatments. © IMechE 2016.

  6. Quantitative assessment of muscular stiffness in children with cerebral palsy using acoustic radiation force impulse (ARFI) ultrasound elastography.

    PubMed

    Bilgici, Meltem Ceyhan; Bekci, Tumay; Ulus, Yasemin; Ozyurek, Hamit; Aydin, Omer Faruk; Tomak, Leman; Selcuk, Mustafa Bekir

    2017-09-12

    To evaluate the feasibility of quantitative analysis of muscle stiffness in the medial gastrocnemius muscle (GCM) by acoustic radiation force impulse (ARFI) ultrasound elastography in children with spastic cerebral palsy (CP). Seventeen children with spastic CP and 25 healthy children participated in the study between the years 2016-2017. The medial GCM in the CP group was assessed using the Modified Ashworth Scale (MAS) by a physiatrist. ARFI was used to measure the shear-wave velocities (SWVs) of the medial GCM. The mean SWV value for each MAS score was calculated and used for statistics. The mean SWV values of the medial GCM in the CP and healthy groups were 3.17 ± 0.81 m/s (mean ± SD) and 1.45 ± 0.25 m/s (mean ± SD), respectively. The SWV of the medial GCM significantly increased in the CP patients when compared with controls (p < 0.001). In addition, the SWV values were correlated with the MAS scores (p < 0.001). The interobserver agreement expressed as the interclass correlation coefficient was 0.65 (95% CI 0.33-0.84, p < 0.001). ARFI imaging demonstrated a difference in muscle stiffness in the medial GCM between the CP and healthy groups. This method is a feasible imaging modality for the noninvasive assessment of contracting muscles in children with CP.

  7. Quantifying differences in the material properties of the fiber regions of the pectoralis major using ultrasound shear wave elastography.

    PubMed

    Leonardis, Joshua M; Desmet, David M; Lipps, David B

    2017-08-10

    The sternocostal and clavicular regions of the pectoralis major are independently harvested to provide shoulder stability, but surgical decision making does not consider the biomechanical consequences that disinsertion of one fiber region over the other has on shoulder function. Differences in material properties between the fiber regions could influence which tissue is more optimal for surgical harvesting. The current study utilized ultrasound shear wave elastography (SWE) to investigate whether the in vivo material properties differ between the fiber regions. Shear wave velocities (SWVs) were collected from the sternocostal and clavicular fiber regions of the pectoralis major from ten healthy young male participants. Participants produced isometric shoulder torques of varying magnitudes (passive, 15%, and 30% MVC) and directions (horizontal and vertical adduction). Four shoulder positions encompassing different vertical abduction and external rotation angles were examined. One-way ANOVAs tested the hypotheses that differences in SWVs during rest existed between the fiber regions asa function of shoulder position, and differences in SWVs during contraction existed asa function of shoulder position and torque direction. In all shoulder positions, the clavicular region exhibited greater SWVs during rest than the sternocostal region (P<0.001). In shoulder positions that did not include external rotation, the clavicular region exhibited greater SWVs during contraction when producing horizontal adduction torques (P<0.001), while the sternocostal region exhibited greater SWVs during contraction when producing vertical adduction torques at 30% MVC (P<0.01). Our results suggest that each fiber region of the pectoralis major provides unique contributions to passive and active shoulder function. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Applications of contrast-enhanced harmonic endoscopic ultrasound on biliary, focal liver lesions and vascular diseases

    PubMed Central

    Choi, Jun-Ho; Seo, Dong-Wan

    2017-01-01

    Over the last decade, the clinical applications of contrast-enhanced harmonic endoscopic ultrasound (CH-EUS) have increased steadily. The development of second-generation ultrasound contrast agents has allowed superior visualization of the microvasculature and tissue perfusion of the target lesion. This methodology has proven useful in the differential diagnosis of solid pancreatic masses and lymph nodes. In addition, the applicability of CH-EUS has expanded to nonpancreas structures such as biliary, focal liver lesions, and vascular disease. This article focuses primarily on the novel applications of CH-EUS in biliary tract and visceral vascular diseases. PMID:28218196

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

    PubMed Central

    Storm, Andrew C; Lee, Linda S

    2016-01-01

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

  10. A Man with Pancreatic Head Mass Lesion on Endoscopic Ultrasound and Granuloma on Cytopathology

    PubMed Central

    Rad, Neda; Heidarnezhad, Arash; Soheili, Setareh; Mohammad-Alizadeh, Amir Houshang; Nikmanesh, Arash

    2016-01-01

    Primary pancreatic lymphoma is an unlikely malignancy accounting for less than 0.5% of pancreatic tumors. Clinical presentation is often nonspecific and may be clinically misdiagnosed as pancreatic adenocarcinoma. Here we present an Iranian case of primary pancreatic lymphoma in a 47-year-old male suffering from jaundice and 20% weight loss. Endoscopic ultrasound revealed a mixed echoic mass lesion at the head of pancreas. The patient underwent endoscopic ultrasound-guided fine needle aspiration of solid pancreatic mass and histopathologic diagnosis revealed granuloma. Computed tomography-guided core needle biopsy was performed and eventually histological examination showed granuloma that was coherent with the diagnosis of primary pancreatic lymphoma. Primary pancreatic lymphoma is a rare entity presenting with nonspecific symptoms, laboratory and radiological findings. Computed tomography results in combination with clinical and radiological studies generally provide guidance for appropriate investigation. PMID:28100998

  11. Giardia lamblia infection diagnosed by endoscopic ultrasound-guided fine-needle aspiration.

    PubMed

    Carter, J Elliot; Nelson, John J; Eves, Matthew; Boudreaux, Carole

    2007-06-01

    The protozoan Giardia lamblia is a major cause of gastrointestinal disease worldwide. We report the case of a 59-yr-old male who presented to his primary care physician with complaints of abdominal pain and weight loss. Imaging studies revealed a liver mass and a pancreatic head mass. Biopsy of the liver mass proved to be benign, and endoscopic ultrasound-guided fine-needle aspiration of the mass in the head of the pancreas showed no evidence of malignancy; however, numerous pear-shaped, binucleated, flagellated organisms morphologically consistent with trophozoites of Giardia lamblia were identified in the specimen. With the increasing use of endoscopic ultrasound-guided fine-needle aspiration for sampling of gastrointestinal, hepatobiliary, and pancreatic lesions, cytopathologists examining such specimens will need to be familiar with the diagnostic characteristics of this protozoal parasite.

  12. The role of endoscopic ultrasound in the diagnosis of gallbladder diseases.

    PubMed

    Chantarojanasiri, Tanyaporn; Hirooka, Yoshiki; Kawashima, Hiroki; Ohno, Eizaburo; Kongkam, Pradermchai; Goto, Hidemi

    2017-01-01

    Endoscopic ultrasound (EUS) has recently played an increasing role in the diagnosis of gallbladder diseases. This review aims to summarize the role of EUS in the diagnosis of gallbladder lesions. EUS provides high-resolution images that can improve the diagnosis of gallbladder polypoid lesions and microlithiasis, in addition to evaluating gallbladder thickness and staging of gallbladder carcinoma. Contrast-enhancing agents may be useful for the differential diagnosis of gallbladder lesions, but the evidence of their effectiveness is still limited and further studies are required in this area to establish its usefulness. Endoscopic ultrasound combined with fine needle aspiration has played an increasing role in providing histological diagnosis of gallbladder tumors in addition to gallbladder thickening.

  13. Sudden appearance of free fluid during endoscopic ultrasound-guided fine-needle aspiration

    PubMed Central

    Rimbaş, Mihai; Deaconu, Marian; Croitoru, Alexandru; Haidar, Andrei

    2016-01-01

    During endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) of a pancreatic malignancy, a small quantity of free fluid, not seen before, suddenly appeared in the view, and time was spent ruling out ongoing hemorrhage. However, during follow-up, the patient gradually developed peritoneal signs and was referred for surgery. The images presented elucidate the diagnosis and raise the question of a theoretical change in diagnostic and therapeutic approach. PMID:26879168

  14. Sudden appearance of free fluid during endoscopic ultrasound-guided fine-needle aspiration.

    PubMed

    Rimbas, Mihai; Deaconu, Marian; Croitoru, Alexandru; Haidar, Andrei

    2016-01-01

    During endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) of a pancreatic malignancy, a small quantity of free fluid, not seen before, suddenly appeared in the view, and time was spent ruling out ongoing hemorrhage. However, during follow-up, the patient gradually developed peritoneal signs and was referred for surgery. The images presented elucidate the diagnosis and raise the question of a theoretical change in diagnostic and therapeutic approach.

  15. Accuracy of endoscopic ultrasound in the evaluation of cystic pancreatic neoplasms: a community hospital experience.

    PubMed

    Wright, Gerald Paul; Morrow, Jay Bradley; Shaheen, Michael; Goslin, Brent J; Baatenburg, Lorel; Chung, Mathew H

    2014-04-01

    Reports on the use of endoscopic ultrasound (EUS) in differentiating benign, premalignant, and malignant pancreatic lesions have been widely variable, particularly with cystic neoplasms. We evaluated the use of EUS for cystic pancreatic lesions in a community hospital setting. All patients who underwent EUS for cystic pancreatic neoplasms from 2007 to 2010 were reviewed. A final EUS diagnosis was determined based on the examiner's impression and fine-needle aspiration results if available. Lesions were stratified as benign, premalignant, or malignant. Patients underwent surgical resection, serial imaging studies, or medical oncology/palliative care consultation as indicated. One hundred eighteen patients with cystic pancreatic lesions underwent EUS during the study period. Endoscopic ultrasound diagnoses included 75 benign (63.6%), 35 premalignant (29.7%), and 8 malignant (4.2%) lesions. Thirty-eight patients (32.2%) underwent surgery, 77 (65.3%) were monitored with imaging, and 3 (2.5%) had unresectable malignancies. Elevated carcinoembryonic antigen levels showed a trend toward predicting mucinous cysts (P = 0.062). Accuracy, sensitivity, specificity, positive predictive value, and negative predictive value for cystic lesions were 87.3%, 86.8%, 87.5%, 76.7%, and 93.3%, respectively. Endoscopic ultrasound is a valuable diagnostic modality in the evaluation of cystic pancreatic neoplasms in a community hospital setting.

  16. [Ultrasound elastography in assessing efficacy of treatment for lower limb varicose veins with a phlebotrophic drug containing a micronized purified flavonoid fraction].

    PubMed

    Zubarev, A R; Krivosheeva, N V; Demidova, a K; Rychkova, I V

    2014-01-01

    Venous hypertension combined with other pathogenetic links of the development of chronic venous insufficiency creates conditions for activation of an inflammatory process. Chronization of inflammation leads to alterations in the histological structure of the vascular wall and perivasal tissues, which is reflected by changes in their physical properties (elasticity or compressibility), which may be studied by means of ultrasound elastography (USEG). The study was aimed at exploring the possibility of using ultrasound elastography for monitoring efficacy of conservative treatment of varicose disease of lower extremities with an agent containing a micronized purified flavonoid fraction (MPFF). we examined a total of 19 patients (38 limbs) presenting with varicose disease of clinical class C2 according to the CEAP classification. The standard ultrasound examination and USEG were carried out using the unit of expert-class "Toshiba" (Japan) with a multi-frequency linear transducer 5-12 Hz. We examined the great saphenous vein in the area of the femur and crus, its tributaries, and the small saphenous vein. All examinations were performed with the patient in the supine, prone and standing positions from the standard approaches in the second half of the day prior to treatment with a phlebotrophic agent containing MPFF (Detralex) and three months after taking the drug at a dose of 1,000 mg/day. at baseline, according to the findings of USEG the intact veins of the lower limbs had a homogeneous pattern of the elastogram in the perivasal area. The presence of varicose transformation was associated with an inhomogeneous elastographic picture. On the background of treatment with MPFF, all patients showed a positive clinical effect in the form of decreased intensity of manifestations of complaints or complete disappearance thereof. According to the findings of ultrasound examination, there was a tendency towards a decrease in the wall thickness and diameter of the examined veins

  17. Three-dimensional electrode displacement elastography using the Siemens C7F2 fourSight four-dimensional ultrasound transducer.

    PubMed

    Bharat, Shyam; Fisher, Ted G; Varghese, Tomy; Hall, Timothy J; Jiang, Jingfeng; Madsen, Ernest L; Zagzebski, James A; Lee, Fred T

    2008-08-01

    Because ablation therapy alters the elastic modulus of tissues, emerging strain imaging methods may enable clinicians for the first time to have readily available, cost-effective, real-time guidance to identify the location and boundaries of thermal lesions. Electrode displacement elastography is a method of strain imaging tailored specifically to ultrasound-guided electrode-based ablative therapies (e.g., radio-frequency ablation). Here tissue deformation is achieved by applying minute perturbations to the unconstrained end of the treatment electrode, resulting in localized motion around the end of the electrode embedded in tissue. In this article, we present a method for three-dimensional (3D) elastographic reconstruction from volumetric data acquired using the C7F2 fourSight four-dimensional ultrasound transducer, provided by Siemens Medical Solutions USA, Inc. (Issaquah, WA, USA). Lesion reconstruction is demonstrated for a spherical inclusion centered in a tissue-mimicking phantom, which simulates a thermal lesion embedded in a normal tissue background. Elastographic reconstruction is also performed for a thermal lesion created in vitro in canine liver using radio-frequency ablation. Postprocessing is done on the acquired raw radio-frequency data to form surface-rendered 3D elastograms of the inclusion. Elastographic volume estimates of the inclusion compare reasonably well with the actual known inclusion volume, with 3D electrode displacement elastography slightly underestimating the true inclusion volume.

  18. Acoustic radiation force impulse elastography for chronic liver disease: comparison with ultrasound-based scores of experienced radiologists, Child-Pugh scores and liver function tests.

    PubMed

    Kim, Ji Eun; Lee, Jae Young; Kim, Yoon Jun; Yoon, Jung Hwan; Kim, Se Hyung; Lee, Jeong Min; Han, Joon Koo; Choi, Byung Ihn

    2010-10-01

    The purpose of our study was to investigate whether acoustic radiation force impulse (ARFI) elastography provides better diagnostic performance for diagnosis of chronic liver disease and correlates better with Child-Pugh scores and liver function tests, compared with an ultrasound (US) scoring system based on visual assessment of conventional B-mode US images by experienced radiologists. Five hundred and twenty-one patients with clinically proven chronic liver disease (n = 293), fatty liver (n = 95) or normal liver (n = 133) were included in this study. B-mode liver US and ARFI elastography were performed in all patients. ARFI elastography was performed at least five times, with each measurement obtained at a different area of the right hepatic lobe; mean shear wave velocity (SWV) was calculated for each patient. The mean SWV was compared with US-based scores from two radiologists (based on liver surface nodularity, parenchyma echotexture and hepatic vein contour), Child-Pugh scores and liver function tests. The mean SWV of the normal liver group was 1.08 m/s ± 0.15; of the fatty liver group, 1.02 m/s ± 0.16; and of the chronic liver disease group, 1.66 m/s ± 0.60 (p < 0.001). The area under the receiver operating characteristics curve of the mean SWV in ARFI elastography was significantly higher than that of the conventional B-mode US-based scores by two radiologists (0.89 vs. 0.74 and 0.77, p < 0.05), with a sensitivity of 75.4% and a specificity of 89.5% at the cut-off value of 1.22 m/s. The sensitivity of the mean SWV was significantly higher than the US-based scores (p < 0.001), although the specificity was not (p > 0.05). The mean SWV was better correlated with Child-Pugh scores and all liver function tests (except total protein) than the US-based scores from two radiologists. In conclusion, ARFI elastography showed better diagnostic performance than visual assessment of experienced radiologists for diagnosis of chronic liver disease, as well as for

  19. SU-E-J-76: Incorporation of Ultrasound Elastography in Target Volume Delineation for Partial Breast Radiotherapy Planning: A Comparative Study

    SciTech Connect

    Juneja, P; Harris, E; Bamber, J

    2014-06-01

    Purpose: There is substantial observer variability in the delineation of target volumes for post-surgical partial breast radiotherapy because the tumour bed has poor x-ray contrast. This variability may result in substantial variations in planned dose distribution. Ultrasound elastography (USE) has an ability to detect mechanical discontinuities and therefore, the potential to image the scar and distortion in breast tissue architecture. The goal of this study was to compare USE techniques: strain elastography (SE), shear wave elastography (SWE) and acoustic radiation force impulse (ARFI) imaging using phantoms that simulate features of the tumour bed, for the purpose of incorporating USE in breast radiotherapy planning. Methods: Three gelatine-based phantoms (10% w/v) containing: a stiff inclusion (gelatine 16% w/v) with adhered boundaries, a stiff inclusion (gelatine 16% w/v) with mobile boundaries and fluid cavity inclusion (to mimic seroma), were constructed and used to investigate the USE techniques. The accuracy of the elastography techniques was quantified by comparing the imaged inclusion with the modelled ground-truth using the Dice similarity coefficient (DSC). For two regions of interest (ROI), the DSC measures their spatial overlap. Ground-truth ROIs were modelled using geometrical measurements from B-mode images. Results: The phantoms simulating stiff scar tissue with adhered and mobile boundaries and seroma were successfully developed and imaged using SE and SWE. The edges of the stiff inclusions were more clearly visible in SE than in SWE. Subsequently, for all these phantoms the measured DSCs were found to be higher for SE (DSCs: 0.91–0.97) than SWE (DSCs: 0.68–0.79) with an average relative difference of 23%. In the case of seroma phantom, DSC values for SE and SWE were similar. Conclusion: This study presents a first attempt to identify the most suitable elastography technique for use in breast radiotherapy planning. Further analysis will

  20. The Expanding Role of Contrast-Enhanced Endoscopic Ultrasound in Pancreatobiliary Disease

    PubMed Central

    Choi, Jun-Ho; Seo, Dong Wan

    2015-01-01

    Since its introduction into clinical practice in the 1980s, endoscopic ultrasound (EUS) has been described as a good imaging modality for the diagnosis of pancreatobiliary diseases. However, differential diagnosis of certain lesions based only on B-mode ultrasound images can be challenging. Clinical use of ultrasound contrast agents has expanded the utility of EUS from that of detection to characterization of pancreatobiliary lesions based on the enhancement features of contrast-enhanced EUS (CE-EUS). Current low mechanical index techniques for CE-EUS using second-generation contrast agents have a number of distinct advantages over conventional diagnostic modalities in evaluating pancreatobiliary lesions, including real-time assessment of perfusion pattern, availability, and the absence of exposure to radiation. This article describes the technical aspects of CE-EUS and reviews the expanding indications in pancreatobiliary diseases and further development of this technique. PMID:26503571

  1. Endoscopic ultrasound-guided biliary drainage versus percutaneous transhepatic biliary drainage after failed endoscopic retrograde cholangiopancreatography: a meta-analysis

    PubMed Central

    Baniya, Ramkaji; Upadhaya, Sunil; Madala, Seetharamprasad; Subedi, Subash Chandra; Shaik Mohammed, Tabrez; Bachuwa, Ghassan

    2017-01-01

    The failure rate of endoscopic retrograde cholangiopancreatography for biliary cannulation is approximately 6%–7% in cases of obstructive jaundice. Percutaneous transhepatic biliary drainage (PTBD) is the procedure of choice in such cases. Endoscopic ultrasound-guided biliary drainage (EGBD) is a novel technique that allows biliary drainage by echoendoscopy and fluoroscopy using a stent from the biliary tree to the gastrointestinal tract. Information in PubMed, Scopus, clinicaltrials.gov and Cochrane review were analyzed to obtain studies comparing EGBD and PTBD. Six studies fulfilled the inclusion criteria. Technical (odds ratio (OR): 0.34; confidence interval (CI) 0.10–1.14; p=0.05) and clinical (OR: 1.48; CI 0.46–4.79; p=0.51) success rates were not statistically significant between the EGBD and PTBD groups. Mild adverse events were nonsignificantly different (OR: 0.36; CI 0.10–1.24; p=0.11) but not the moderate-to-severe adverse events (OR: 0.16; CI 0.08–0.32; p≤0.00001) and total adverse events (OR: 0.34; CI 0.20–0.59; p≤0.0001). EGBD is equally effective but safer than PTBD. PMID:28408850

  2. Endoscope

    MedlinePlus

    An endoscope is a medical device with a light attached. It is used to look inside a body cavity ... sigmoidoscopy . A medical procedure using any type of endoscope is called an endoscopy . See also: Colonoscopy Cystourethroscopy ...

  3. Utility and interobserver agreement of ultrasound elastography in the detection of malignant thyroid nodules in clinical care.

    PubMed

    Merino, S; Arrazola, J; Cárdenas, A; Mendoza, M; De Miguel, P; Fernández, C; Ganado, T

    2011-12-01

    Malignancy correlates with hardness of tissues and US elastography can potentially analyze the stiffness of lesions. Our aim was to evaluate the utility of US elastography in the detection of malignant nodules and to investigate interobserver agreement with this technique. One-hundred three consecutive patients with 106 thyroid nodules were examined prospectively with conventional B-mode sonography and real-time US elastography. All patients were referred for FNAB. Conventional B-mode sonography and US elastographic examinations were performed, and images were separated and independently interpreted by 2 radiologists blinded to pathologic results. US elastogram evaluation was based on a simplified classification of stiffness based on gray-scale patterns, tumor size compared with B-mode, and margins. Interobserver agreement was studied. FNAB was used as the reference standard for the diagnosis of benign nodules, but histopathologic evaluations were performed when results suspicious for malignancy or malignant results were obtained on FNAB as well as in indeterminate lesions. In our study, pattern of stiffness based on gray-scale and classification proposed were statistically significant and predicted malignancy with 100% sensitivity and 40.6% specificity. Tumor size when compared with B-mode images or margins was not statistically significant in our study. No false-negatives were found, and an NPV of 100% was seen. Interobserver agreement for US elastography was excellent in our study, with a κ index of 0.82 (95% CI). We believe that US elastography is a promising technique that can assist in the evaluation of thyroid nodules and can potentially diminish the number of FNAB procedures needed. We believe that it may be useful to introduce US elastography into routine clinical practice.

  4. [Contrastive study on conventional ultrasound, compression elastography and acoustic radiation force impulse imaging in the differential diagnosis of benign and malignant breast tumors].

    PubMed

    Zhang, Lu; Zhou, Ping; Deng, Jin; Tian, Shuangming; Qian, Ying; Wu, Xiaomin; Ma, Shuhua; Li, Jiale

    2014-12-01

    To evaluate the diagnostic performance of conventional ultrasound, compression elastography (CE) and acoustic radiation force impulse imaging (ARFI) in differential diagnosis of benign and malignant breast tumors. A total of 98 patients with liver lesions were included in the study. The images of conventional ultrasound, CE and the values of virtual touch tissue quantification (VTQ) of breast lesions were obtained. The diagnostic performance of conventional ultrasound, CE and ARFI were assessed by using pathology as the gold standard, and then evaluate the diagnosis efficiency of these three approaches in differential diagnosing benign and malignant breast tumors. The specificity, sensitivity and accuracy in the diagnosis of malignant breast tumors for conventional ultrasound were 80.0%, 81.1% and 81.7%, respectively, whereas for CE elastic score were 85.7%, 86.7% and 86.3%, respectively. With a cutoff value of 3.71 for the SR, the sensitivity, specificity, accuracy in diagnosis of malignant breast tumors were 97.1%, 83.3% and 88.4%, respectively. With a cutoff value of 3.78 m/s for VTQ, the sensitivity, specificity, accuracy in diagnosis of malignant breast tumors were 94.3%, 91.7% and 92.6%, respectively. The difference in diagnosis efficiency among ARFI, CE and conventional ultrasound in differential diagnosis of benign and malignant breast tumors was significant (P< 0.05). Conventional ultrasound, CE and ARFI are all useful for the differential diagnosis of benign and malignant breast tumors. But the diagnosis efficiency of ARFI is superior to CE and conventional ultrasound. The three approaches can help each other in differential diagnosis of benign and malignant breast tumors.

  5. Endoscopic ultrasound-guided ethanol ablation therapy for tumors

    PubMed Central

    Zhang, Wen-Ying; Li, Zhao-Shen; Jin, Zhen-Dong

    2013-01-01

    Endoscopic ultrasonography (EUS) has evolved into a useful therapeutic tool for treating a broad range of tumors since being introduced into clinical practice as a diagnostic modality nearly three decades ago. In particular, EUS-guided fine-needle injection has proven a successful minimally invasive approach for treating benign lesions such as pancreatic cysts, relieving pancreatic pain through celiac plexus neurolysis, and controlling local tumor growth of unresectable malignancies by direct delivery of anti-tumor agents. One such ablative agent, ethanol, is capable of safely ablating solid or cystic lesions in hepatic tissues via percutaneous injection. Recent research and clinical interest has focused on the promise of EUS-guided ethanol ablation as a safe and effective method for treating pancreatic tumor patients with small lesions or who are poor operative candidates. Although it is not likely to replace radical resection of localized lesions or systemic treatment of metastatic tumors in all patients, EUS-guided ablation is an ideal method for patients who refuse or are not eligible for surgery. Moreover, this treatment modality may play an active role in the development of future pancreatic tumor treatments. This article reviews the most recent clinical applications of EUS-guided ethanol ablation in humans for treating pancreatic cystic tumors, pancreatic neuroendocrine tumors, and metastatic lesions. PMID:23801831

  6. Assessment of the accuracy of an ultrasound elastography liver scanning system using a PVA-cryogel phantom with optimal acoustic and mechanical properties

    NASA Astrophysics Data System (ADS)

    Cournane, S.; Cannon, L.; Browne, J. E.; Fagan, A. J.

    2010-10-01

    The accuracy of a transient elastography liver-scanning ultrasound system was assessed using a novel application of PVA-cryogel as a tissue-mimicking material with acoustic and shear elasticity properties optimized to best represent those of liver tissue. Although the liver-scanning system has been shown to offer a safer alternative for diagnosing liver cirrhosis through stiffness measurement, as compared to the liver needle biopsy exam, the scanner's accuracy has not been fully established. Young's elastic modulus values of 5-6 wt% PVA-cryogel phantoms, also containing glycerol and 0.3 µm Al2O3 and 3 µm Al2O3, were measured using a 'gold standard' mechanical testing technique and transient elastography. The mechanically measured values and acoustic velocities of the phantoms ranged between 1.6 and 16.1 kPa and 1540 and 1570 m s-1, respectively, mimicking those observed in liver tissue. The values reported by the transient elastography system overestimated Young's elastic modulus values representative of the progressive stages of liver fibrosis by up to 32%. These results were attributed to the relative rather than absolute nature of the measurement arising from the single-point acoustic velocity calibration of the system, rendering the measurements critically dependent on the speed of sound of the sample under investigation. Given the wide range of acoustic velocities which exist in the liver, spanning healthy tissue to cirrhotic pathology, coupled with the system's assumption that the liver is approximately elastic when it is rather highly viscoelastic, care should be exercised when interpreting the results from this system in patient groups.

  7. Assessment of the accuracy of an ultrasound elastography liver scanning system using a PVA-cryogel phantom with optimal acoustic and mechanical properties.

    PubMed

    Cournane, S; Cannon, L; Browne, J E; Fagan, A J

    2010-10-07

    The accuracy of a transient elastography liver-scanning ultrasound system was assessed using a novel application of PVA-cryogel as a tissue-mimicking material with acoustic and shear elasticity properties optimized to best represent those of liver tissue. Although the liver-scanning system has been shown to offer a safer alternative for diagnosing liver cirrhosis through stiffness measurement, as compared to the liver needle biopsy exam, the scanner's accuracy has not been fully established. Young's elastic modulus values of 5-6 wt% PVA-cryogel phantoms, also containing glycerol and 0.3 µm Al(2)O(3) and 3 µm Al(2)O(3), were measured using a 'gold standard' mechanical testing technique and transient elastography. The mechanically measured values and acoustic velocities of the phantoms ranged between 1.6 and 16.1 kPa and 1540 and 1570 m s(-1), respectively, mimicking those observed in liver tissue. The values reported by the transient elastography system overestimated Young's elastic modulus values representative of the progressive stages of liver fibrosis by up to 32%. These results were attributed to the relative rather than absolute nature of the measurement arising from the single-point acoustic velocity calibration of the system, rendering the measurements critically dependent on the speed of sound of the sample under investigation. Given the wide range of acoustic velocities which exist in the liver, spanning healthy tissue to cirrhotic pathology, coupled with the system's assumption that the liver is approximately elastic when it is rather highly viscoelastic, care should be exercised when interpreting the results from this system in patient groups.

  8. Liver elastography, comments on EFSUMB elastography guidelines 2013

    PubMed Central

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

    2013-01-01

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

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

    PubMed Central

    Săftoiu, Adrian; Vilmann, Peter; Bhutani, Manoop S.

    2016-01-01

    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 of intensity of the contrast signal through time-intensity curve analysis. Thus, contrast harmonic imaging-EUS has been used to differentiate pancreatic adenocarcinoma based on lower values of the peak enhancement. Future applications of CE-EUS in pancreatic adenocarcinoma include not only use of targeted 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 through sonoporation and ultrasound-induced release of the drugs locally. PMID:28000627

  10. The role of endoscopic ultrasound in the evaluation of rectal polypoid lesions in 25 dogs.

    PubMed

    Hayashi, Kohtaro; Okanishi, Hiroki; Kagawa, Yumiko; Asano, Kazushi; Watari, Toshihiro

    2012-11-01

    We investigated the role of endoscopic ultrasound in the evaluation of rectal polypoid lesions in 25 dogs. Twenty-five cases of rectal polypoid lesions in dogs who underwent surgery after endoscopic and EUS assessment were studied. The invasion depth of the polypoid lesion was classified as M stage (lesions in the mucosa only), SM stage (lesions in the mucosa and submucosa), and MP stage (lesions extending to the muscularis propria). Transabdominal ultrasound was performed in nine cases, but not all were evaluated in detail. EUS provided detailed images for all cases and showed a significant correlation with surgical pathology in the T stage (accuracy, 92%; K = 0.77). As per classification by invasion depth, inflammatory polyps were only M polypoid lesions, whereas SM and MP polypoid lesions were only adenocarcinomas (P < 0.05). The average survival time according to specific condition was as follows: 1,235 days for inflammatory polyps, and 804 days for M adenocarcinoma. The survival time of two SM adenocarcinoma cases was 756 and 2,114 days, respectively, and the survival time of two MP adenocarcinoma cases was 16 and 42 days, respectively. EUS were useful for the evaluation of rectal polypoid lesions in dogs, whereas transabdominal ultrasound was not. Determination of the invasion depth of polypoid lesions using EUS may be useful for the evaluation of malignancy and prognosis.

  11. The role of viscosity estimation for oil-in-gelatin phantom in shear wave based ultrasound elastography.

    PubMed

    Zhu, Ying; Dong, Changfeng; Yin, Yin; Chen, Xin; Guo, Yanrong; Zheng, Yi; Shen, Yuanyuan; Wang, Tianfu; Zhang, Xinyu; Chen, Siping

    2015-02-01

    Shear wave based ultrasound elastography utilizes mechanical excitation or acoustic radiation force to induce shear waves in deep tissue. The tissue response is monitored to obtain elasticity information about the tissue. During the past two decades, tissue elasticity has been extensively studied and has been used in clinical disease diagnosis. However, biological soft tissues are viscoelastic in nature. Therefore, they should be simultaneously characterized in terms of elasticity and viscosity. In this study, two shear wave-based elasticity imaging methods, shear wave dispersion ultrasound vibrometry (SDUV) and acoustic radiation force impulsive (ARFI) imaging, were compared. The discrepancy between the measurements obtained by the two methods was analyzed, and the role of viscosity was investigated. To this end, four types of gelatin phantoms containing 0%, 20%, 30% and 40% castor oil were fabricated to mimic different viscosities of soft tissue. For the SDUV method, the shear elasticity μ1 was 3.90 ± 0.27 kPa, 4.49 ± 0.16 kPa, 2.41 ± 0.33 kPa and 1.31 ± 0.09 kPa; and the shear viscosity μ2 was 1.82 ± 0.31 Pa•s, 2.41 ± 0.35 Pa•s, 2.65 ± 0.13 Pa•s and 2.89 ± 0.14 Pa•s for 0%, 20%, 30% and 40% oil, respectively in both cases. For the ARFI measurements, the shear elasticity μ was 7.30 ± 0.20 kPa, 8.20 ± 0.31 kPa, 7.42 ± 0.21 kPa and 5.90 ± 0.36 kPa for 0%, 20%, 30% and 40% oil, respectively. The SDUV results demonstrated that the elasticity first increased from 0% to 20% oil and then decreased for the 30% and 40% oil. The viscosity decreased consistently as the concentration of castor oil increased from 0% to 40%. The elasticity measured by ARFI showed the same trend as that of the SDUV but exceeded the results measured by SDUV. To clearly validate the impact of viscosity on the elasticity estimation, an independent measurement of the elasticity and viscosity by dynamic mechanical analysis (DMA) was conducted on these four types of gelatin

  12. Placement of multiple metal stents for malignant intrahepatic biliary obstruction via an endoscopic ultrasound-guided choledochoduodenostomy fistula.

    PubMed

    Akiyama, Dai; Hamada, Tsuyoshi; Nakai, Yousuke; Isayama, Hiroyuki; Takagi, Kaoru; Mizuno, Suguru; Koike, Kazuhiko

    2015-01-01

    Endoscopic ultrasound-guided choledochoduodenostomy (EUS-CDS) using a fully-covered self-expandable metal stent (SEMS) is increasingly used as an alternative to failed endoscopic retrograde cholangiopancreatography. An EUS-CDS fistula can provide endoscopists with a new approach route for intrahepatic bile ducts. Here, we present successful placement of multiple SEMS for intrahepatic biliary obstruction via an EUS-CDS fistula.

  13. Endoscopic ultrasound-guided fine needle aspiration: How to obtain a core biopsy?

    PubMed Central

    Fuccio, Lorenzo; Larghi, Alberto

    2014-01-01

    Endoscopic ultrasound (EUS)-guided fine needle aspiration has emerged as the procedure of choice to obtain samples to reach a definitive diagnosis of lesions of the gastrointestinal tract and of adjacent organs. The obtainment of a tissue core biopsy presents several advantages that can substantially contribute to the widespread diffusion of EUS utilization in the community and in countries where cytology expertise may be difficult to be achieved. This article will review the EUS-guided fine needle biopsy techniques developed so far, the clinical results, their limitations as well as their future perspective. PMID:24955336

  14. Endoscopic ultrasound-guided fine-needle aspiration needles: which one and in what situation?

    PubMed

    Karadsheh, Zeid; Al-Haddad, Mohammad

    2014-01-01

    Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is increasingly used as a diagnostic and therapeutic tool for pancreatic and other gastrointestinal disorders. Several factors affect the outcome of EUS-FNA, one of which is needle size. The decision to use a specific needle depends on factors including location, consistency, and type of the lesion; presence of onsite cytopathologist; and need for additional tissue procurement for histology. This review provides a balanced perspective on the use of different needle sizes available, highlighting the differences among them and potential niche applications of each to maximize diagnostic yield of EUS-FNA. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. Role of Endoscopic Ultrasound for the Diagnosis of Isolated Gastric Cavernous Haemangioma

    PubMed Central

    Hu, Jinlong; Sao, Hua

    2016-01-01

    Isolated gastric cavernous haemangioma is extremely rare in the stomach. Historically, endoscopy, computed tomography and MRI had been used to diagnose gastric cavernous haemangioma. Biopsy, is not an option due to its vascular nature and submucosal location. We report an isolated gastric cavernous haemangioma that was diagnosed by end-oscopic ultrasound in a 25-year-old male and treated by laparotomy. The final diagnosis of cavernous haemagioma was confirmed by post-operative pathology. There was no recurrence during 3-month follow-up period. PMID:27790564

  16. Estimation of polyvinyl alcohol cryogel mechanical properties with four ultrasound elastography methods and comparison with gold standard testings.

    PubMed

    Fromageau, Jérémie; Gennisson, Jean-Luc; Schmitt, Cédric; Maurice, Roch L; Mongrain, Rosaire; Cloutier, Guy

    2007-03-01

    Tissue-mimicking phantoms are very useful in the field of tissue characterization and essential in elastography for the purpose of validating motion estimators. This study is dedicated to the characterization of polyvinyl alcohol cryogel (PVA-C) for these types of applications. A strict fabrication procedure was defined to optimize the reproducibility of phantoms having a similar elasticity. Following mechanical stretching tests, the phantoms were used to compare the accuracy of four different elastography methods. The four methods were based on a one-dimensional (1-D) scaling factor estimation, on two different implementations of a 2-D Lagrangian speckle model estimator (quasistatic elastography methods), and on a 1-D shear wave transient elastography technique (dynamic method). Young's modulus was investigated as a function of the number of freeze-thaw cycles of PVA-C, and of the concentration of acoustic scatterers. Other mechanical and acoustic parameters-such as the speed of sound, shear wave velocity, mass density, and Poisson's ratio-also were assessed. The Poisson's ratio was estimated with good precision at 0.499 for all samples, and the Young's moduli varied in a range of 20 kPa for one freeze-thaw cycle to 600 kPa for 10 cycles. Nevertheless, above six freeze-thaw cycles, the results were less reliable because of sample geometry artifacts. However, for the samples that underwent less than seven freeze-thaw cycles, the Young's moduli estimated with the four elastography methods showed good matching with the mechanical tensile tests with a regression coefficient varying from 0.97 to 1.07, and correlations R2 varying from 0.93 to 0.99, depending on the method.

  17. Endoscopic ultrasound findings predict the recurrence of esophageal varices after endoscopic band ligation: a prospective cohort study.

    PubMed

    Masalaite, Laura; Valantinas, Jonas; Stanaitis, Juozas

    2015-01-01

    Variceal recurrence following endoscopic band ligation (EBL) is common. Esophageal collateral veins (ECV) are observed by endoscopic ultrasound (EUS) in patients with portal hypertension. The aim of the present study was to assess the role of EUS in predicting the recurrence of esophageal varices following EBL. Forty patients who had undergone EBL for eradication of varices were examined over a 12-month period to detect variceal recurrence. EUS was performed before ligation to detect and describe the type, grade, and the number of ECV. EUS findings obtained prior to EBL were compared in the variceal recurrence and non-recurrence groups. Of the 40 patients, 19 (47.5%) had variceal recurrence within 12 months of EBL. Univariate logistic regression analysis showed that severe peri-ECV (p < 0.001), multiple peri-ECV (p < 0.001), and the presence of perforating veins (p < 0.014) were statistically significantly related to the variceal recurrence after EBL. Multivariate logistic regression model found that only severe peri-ECV (odds ratio [OR] = 24.39; 95% confidence interval [CI]: 2.34-253.78) and multiple peri-ECV (OR = 24.39; 95% CI: 2.34-253.78) remained as independent prognostic factors for variceal recurrence. The sensitivity and specificity of multivariate logistic regression model in predicting variceal recurrence was 89.2% and 90.5%, respectively (prognostic value (AUC) = 0.946). Recurrence rate of esophageal varices after EBL is high (47.5%). EUS can clearly depict ECV and has a value in predicting variceal recurrence after EBL; severe peri-ECV and multiple peri-ECV were significant and independent prognostic factors associated with variceal recurrence risk.

  18. Novel Use of Ultrasound Elastography to Quantify Muscle Tissue Changes After Dry Needling of Myofascial Trigger Points in Patients With Chronic Myofascial Pain.

    PubMed

    Turo, Diego; Otto, Paul; Hossain, Murad; Gebreab, Tadesse; Armstrong, Katherine; Rosenberger, William F; Shao, Hui; Shah, Jay P; Gerber, Lynn H; Sikdar, Siddhartha

    2015-12-01

    To compare a mechanical heterogeneity index derived from ultrasound vibration elastography with physical findings before and after dry-needling treatment of spontaneously painful active myofascial trigger points in the upper trapezius muscle. Forty-eight patients with chronic myofascial pain enrolled in a prospective interventional trial of 3 weekly dry-needling treatments for active myofascial trigger points. Trigger points were evaluated at baseline and at treatment completion using palpation, the pressure-pain threshold, and the mechanical heterogeneity index. Thirty patients were reevaluated at 8 weeks. Trigger points that "responded" changed to tissue that was no longer spontaneously painful, with or without the presence of a palpable nodule. Trigger points that "resolved" changed to tissue without a palpable nodule. The mechanical heterogeneity index was defined as the proportion of the upper trapezius muscle that appeared mechanically stiffer on elastography. Statistical significance for comparisons was determined at P < .05. Following 3 dry needle treatments, the mechanical heterogeneity index decreased significantly for the 38 myofascial trigger points (79% of 48) that responded to treatment. Among these, the baseline mechanical heterogeneity index was significantly lower for the 13 trigger points (27% of 38) that resolved, but the decrease after 3 dry needle treatments did not reach significance. The pressure-pain threshold improved significantly for both groups. At 8 weeks, the mechanical heterogeneity index decreased significantly for the 22 trigger points (73% of 30) that responded and for the 10 (45% of 22) that resolved. The pressure-pain threshold improvement was significant for trigger points that responded but did not reach significance for resolved trigger points. The mechanical heterogeneity index identifies changes in muscle tissue properties that correlate with changes in the myofascial trigger point status after dry needling. © 2015 by the

  19. Real-time elastography of the prostate.

    PubMed

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

    2014-01-01

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

  20. Real-Time Elastography of the Prostate

    PubMed Central

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

    2014-01-01

    Palpation of organs is one of the oldest clinical examination techniques, for instance, if you think of the palpation of the breast or the digital rectal examination of the prostate, where hard palpable regions are suspicious for cancer. This is the basic principle of real-time elastography, an ultrasound technique, which is able to visualise tissue elasticity. Since prostate cancer features an increased stiffness due to the higher cell and vessel density than the normal surrounding tissue, real-time elastography has been used for several years for prostate cancer detection. This review introduces the different techniques of ultrasound elastography and furthermore summarises its limitations and potentials. PMID:24967334

  1. Endoscopic ultrasound evaluation in the surgical treatment of duodenal and peri-ampullary adenomas

    PubMed Central

    Azih, Lilian C; Broussard, Brett L; Phadnis, Milind A; Heslin, Martin J; Eloubeidi, Mohamad A; Varadarajulu, Shayam; Arnoletti, Juan Pablo

    2013-01-01

    AIM: To investigate endoscopic ultrasound (EUS) for predicting depth of mucosal invasion and to analyze outcomes following endoscopic and transduodenal resection. METHODS: Records of 111 patients seen at our institution from November 1999 to July 2011 with the post-operative pathological diagnosis of benign ampullary and duodenal adenomas were reviewed. Records of patients who underwent preoperative EUS for diagnostic purposes were identified. The accuracy of EUS in predicting the absence of muscular invasion was assessed by comparing EUS reports to the final surgical pathological results. In addition, the incidence of the post-operative complications over a period of 30 d and the subsequent long-term outcome (recurrence) over a period of 30 mo associated with endoscopic and transduodenal surgical resection was recorded, compared and analyzed. RESULTS: Among 111 patients with benign ampullary and duodenal adenomas, 47 underwent preoperative EUS for 29 peri-ampullary lesions and 18 duodenal lesions. In addition, computed tomography was performed in 18 patients, endoscopic retrograde cholangio-pancreatography in 10 patients and esophagogastroduodenoscopy in 22 patients. There were 43 patients with sporadic adenomas and 4 patients with familial adenomatous polyposis (FAP)/other polyposis syndromes. In 38 (81%, P < 0.05) patients, EUS reliably identified absence of submucosal and muscularis invasion. In 4 cases, EUS underestimated submucosal invasion that was proven by pathology. In the other 5 patients, EUS predicted muscularis invasion which could not be demonstrated in the resected specimen. EUS predicted tumor muscularis invasion with a specificity of 88% and negative predictive value of 90% (P < 0.05). Types of resection performed included endoscopic resection in 22 cases, partial duodenectomy in 9 cases, transduodenal ampullectomy with sphincteroplasty in 10 cases and pancreaticoduodenectomy in 6 cases. The main post-operative final pathological results included

  2. Role of endoscopic ultrasound in idiopathic acute pancreatitis with negative ultrasound, computed tomography, and magnetic resonance cholangiopancreatography

    PubMed Central

    Rana, Surinder Singh; Bhasin, Deepak Kumar; Rao, Chalapathi; Singh, Kartar

    2012-01-01

    Background Idiopathic acute pancreatitis (IAP) is a diagnostic challenge. Finding a treatable cause after appropriate investigation may help to prevent recurrent pancreatitis and further management. The aim of our study was to retrospectively report our experience with endoscopic ultrasound (EUS) in investigating patients with IAP. Methods Forty patients (26 males; age range: 17-72 years) of IAP with no underlying cause identified on transabdominal ultrasound, computed tomography and magnetic resonance cholangiopancreatography were studied. In 23 patients (57.5%), it was the first attack of acute pancreatitis whereas in 17 patients (42.5%) there was at least one previous attack of documented acute pancreatitis. EUS examination was done using a radial echoendoscope. Results Twenty (50%) of the patients had biliary tract disease (cholelithiasis in 3, gallbladder sludge in 13, choledocholithiasis in 1 and common bile duct sludge in 3 patients). One each had an 8 mm tumor in the head of pancreas and pancreas divisum. No underlying cause could be found in 18 (45%) patients. Nine patients had features of chronic pancreatitis (CP) and the remaining had a normal pancreas. Conclusions Occult biliary pathology is the predominant cause of IAP. Half of the cases without identified etiology already had an underlying CP. EUS is a very important tool in evaluating IAP especially after an initial negative diagnostic workup. PMID:24714266

  3. A Risk Model for Predicting Central Lymph Node Metastasis of Papillary Thyroid Microcarcinoma Including Conventional Ultrasound and Acoustic Radiation Force Impulse Elastography

    PubMed Central

    Xu, Jun-Mei; Xu, Hui-Xiong; Li, Xiao-Long; Bo, Xiao-Wan; Xu, Xiao-Hong; Zhang, Yi-Feng; Guo, Le-Hang; Liu, Lin-Na; Qu, Shen

    2016-01-01

    Abstract The aim of this prospective study was to propose a new rating system using a risk model including conventional ultrasound (US) and acoustic radiation force impulse (ARFI) elastography for predicting central lymph node metastasis (LNM) in patients with papillary thyroid microcarcinoma (PTMC). A total of 252 patients with PTMCs were enrolled, who were preoperatively evaluated by US and ARFI elastography including virtual touch tissue imaging (VTI) and virtual touch tissue quantification (VTQ). Risk factors of independent variables for central LNM were analyzed by univariate and multivariate analyses. A multivariate analysis was performed to create a predicting model and rating system. Of the 252 patients, 72 (28.6%) had central LNMs. Multivariate analysis revealed that rare internal flow (odds ratio [OR]: 4.454), multiple suspicious foci on US (OR: 5.136), capsule involvement (OR: 20.632), and VTI area ratio (VAR) > 1 (OR: 5.621) were independent risk factors for central LNM. The final predicting model was obtained and the risk score (RS) was defined as 1.5 × (if rare internal flow) + 1.6 × (if multiple suspicious foci on US) + 1.7 × (if VAR > 1) + 3.0 × (if capsule involvement). The rating system was divided into 5 stages. Stage I, <1.5; Stage II, 1.5 to 3.0; Stage III, 3.1 to 4.7; Stage IV, 4.8 to 6.3; and Stage V, 6.4 to 7.8. The risk rates of central LNM were 3.4% (2/59) in Stage I, 13.3% (13/98) in Stage II, 54.2% (39/72) in Stage III, 72.2% (13/18) in Stage IV, and 100% (5/5) in Stage V (P < 0.001). The results indicated that rare internal flow, multiple suspicious foci, capsule involvement on US, and VAR > 1 on ARFI elastography are the risk factors for predicting central LNM. The risk model developed in the study clearly predicts the risk of central LNM in patients with PTMC and thus has a potential to avoid unnecessary central compartment node dissection. PMID:26817907

  4. Evaluation of Elastic Stiffness in Healing Achilles Tendon After Surgical Repair of a Tendon Rupture Using In Vivo Ultrasound Shear Wave Elastography.

    PubMed

    Zhang, Li-ning; Wan, Wen-bo; Wang, Yue-xiang; Jiao, Zi-yu; Zhang, Li-hai; Luo, Yu-kun; Tang, Pei-fu

    2016-04-09

    BACKGROUND There has been no published report assessing the mechanical properties of a repaired Achilles tendon after surgery using shear wave elastography (SWE). The aim of this study was to investigate the changes in mechanical properties of the healing Achilles tendon after surgical repair of a tendon rupture using ultrasound SWE and how these changes correlate with tendon function. MATERIAL AND METHODS Twenty-six patients who underwent surgical repair for Achilles tendon rupture were examined with ultrasound SWE coupled with a linear array transducer (4-15 MHz). The elasticity values of the repaired Achilles tendon in a longitudinal view were measured at 12, 24, and 48 weeks postoperatively. Functional outcomes were assessed with the American Orthopedic Foot and Ankle Society (AOFAS) rating system at 12, 24, and 48 weeks postoperatively. General linear regression analysis and correlation coefficients were used to analyze the relationship between elasticity and the AOFAS score. RESULTS There were significant differences with respect to the mean elasticity values and functional scores of the repaired Achilles tendon at 12, 24, and 48 weeks postoperatively (all P<0.05). Tendon function was positively correlated with the elasticity of the repaired Achilles tendon (P=0.0003). CONCLUSIONS Our findings suggest that SWE can provide biomechanical information for evaluating the mechanical properties of healing Achilles tendon and predict Achilles tendon function.

  5. Evaluation of Elastic Stiffness in Healing Achilles Tendon After Surgical Repair of a Tendon Rupture Using In Vivo Ultrasound Shear Wave Elastography

    PubMed Central

    Zhang, Li-ning; Wan, Wen-bo; Wang, Yue-xiang; Jiao, Zi-yu; Zhang, Li-hai; Luo, Yu-kun; Tang, Pei-fu

    2016-01-01

    Background There has been no published report assessing the mechanical properties of a repaired Achilles tendon after surgery using shear wave elastography (SWE). The aim of this study was to investigate the changes in mechanical properties of the healing Achilles tendon after surgical repair of a tendon rupture using ultrasound SWE and how these changes correlate with tendon function. Material/Methods Twenty-six patients who underwent surgical repair for Achilles tendon rupture were examined with ultrasound SWE coupled with a linear array transducer (4–15 MHz). The elasticity values of the repaired Achilles tendon in a longitudinal view were measured at 12, 24, and 48 weeks postoperatively. Functional outcomes were assessed with the American Orthopedic Foot and Ankle Society (AOFAS) rating system at 12, 24, and 48 weeks postoperatively. General linear regression analysis and correlation coefficients were used to analyze the relationship between elasticity and the AOFAS score. Results There were significant differences with respect to the mean elasticity values and functional scores of the repaired Achilles tendon at 12, 24, and 48 weeks postoperatively (all P<0.05). Tendon function was positively correlated with the elasticity of the repaired Achilles tendon (P=0.0003). Conclusions Our findings suggest that SWE can provide biomechanical information for evaluating the mechanical properties of healing Achilles tendon and predict Achilles tendon function. PMID:27072885

  6. Assessing Age-Related Changes in the Biomechanical Properties of Rabbit Lens Using a Coaligned Ultrasound and Optical Coherence Elastography System

    PubMed Central

    Wu, Chen; Han, Zhaolong; Wang, Shang; Li, Jiasong; Singh, Manmohan; Liu, Chih-hao; Aglyamov, Salavat; Emelianov, Stanislav; Manns, Fabrice; Larin, Kirill V.

    2015-01-01

    Purpose. To evaluate the capability of a novel, coaligned focused ultrasound and phase-sensitive optical coherence elastography (US-OCE) system to assess age-related changes in biomechanical properties of the crystalline lens in situ. Methods. Low-amplitude elastic deformations in young and mature rabbit lenses were measured by an US-OCE system consisting of a spectral-domain optical coherence tomography (OCT) system coaligned with a focused ultrasound system used to produce a transient force on the lens surface. Uniaxial compressional tests were used to validate the OCE data. Results. The OCE measurements showed that the maximum displacements of the young rabbit lenses were significantly larger than those of the mature lenses, indicating a gradual increase of the lens stiffness with age. Temporal analyses of the displacements also demonstrate a similar trend of elastic properties in these lenses. The stress-strain measurements using uniaxial mechanical tests confirmed the results obtained by the US-OCE system. Conclusions. The results demonstrate that the US-OCE system can be used for noninvasive analysis and quantification of lens biomechanical properties in situ and possibly in vivo. PMID:25613945

  7. Novel Use of Ultrasound Elastography to Quantify Muscle Tissue Changes After Dry Needling of Myofascial Trigger Points in Patients With Chronic Myofascial Pain

    PubMed Central

    Turo, Diego; Otto, Paul; Hossain, Murad; Gebreab, Tadesse; Armstrong, Katherine; Rosenberger, William F.; Shao, Hui; Shah, Jay P.; Gerber, Lynn H.; Sikdar, Siddhartha

    2017-01-01

    Objectives To compare a mechanical heterogeneity index derived from ultrasound vibration elastography with physical findings before and after dry-needling treatment of spontaneously painful active myofascial trigger points in the upper trapezius muscle. Methods Forty-eight patients with chronic myofascial pain enrolled in a prospective interventional trial of 3 weekly dry-needling treatments for active myofascial trigger points. Trigger points were evaluated at baseline and at treatment completion using palpation, the pressure-pain threshold, and the mechanical heterogeneity index. Thirty patients were reevaluated at 8 weeks. Trigger points that “responded” changed to tissue that was no longer spontaneously painful, with or without the presence of a palpable nodule. Trigger points that “resolved” changed to tissue without a palpable nodule. The mechanical heterogeneity index was defined as the proportion of the upper trapezius muscle that appeared mechanically stiffer on elastography. Statistical significance for comparisons was determined at P < .05. Results Following 3 dry needle treatments, the mechanical heterogeneity index decreased significantly for the 38 myofascial trigger points (79% of 48) that responded to treatment. Among these, the baseline mechanical heterogeneity index was significantly lower for the 13 trigger points (27% of 38) that resolved, but the decrease after 3 dry needle treatments did not reach significance. The pressure-pain threshold improved significantly for both groups. At 8 weeks, the mechanical heterogeneity index decreased significantly for the 22 trigger points (73% of 30) that responded and for the 10 (45% of 22) that resolved. The pressure-pain threshold improvement was significant for trigger points that responded but did not reach significance for resolved trigger points. Conclusions The mechanical heterogeneity index identifies changes in muscle tissue properties that correlate with changes in the myofascial trigger

  8. Endoscopic Ultrasound-Guided Treatment of Pancreatic Cystic and Solid Masses

    PubMed Central

    2015-01-01

    Pancreatic tumor is one of the most difficult diseases to diagnose and treat because of its anatomical location and characteristics. Recently, there have been several innovative trials on the treatment of pancreatic tumors using endoscopic ultrasound (EUS) because it allows selective access to the difficult to reach target organ along the gastrointestinal tract and can differentiate vessels by color Doppler. Among these trials, several have investigated EUS-guided ethanol lavage with or without paclitaxel for pancreatic cystic tumors. These studies show a 33% to 79% complete resolution rate with a favorable safety profile. Compared to EUS-guided ethanol lavage for pancreatic cystic tumors, EUS-guided radiofrequency ablation is considered a less invasive treatment method for pancreatic cancer. Although there are still several difficulties and concerns about complications, one clinical study reported 72.8% feasibility with favorable safety, and therefore, we anticipate the results of ongoing studies with these new less invasive techniques. PMID:26240804

  9. Diagnostic yield of endoscopic ultrasound in patients with hypoglicemia and insulinoma suspected

    PubMed Central

    Téllez-Ávila, Félix Ignacio; Acosta-Villavicencio, Gladys Yolanda; Chan, Carlos; Hernández-Calleros, Jorge; Uscanga, Luis; Valdovinos-Andraca, Francisco; Ramírez-Luna, Miguel Ángel

    2015-01-01

    Background and Objectives: Noninvasive imaging techniques have shown limitations to identify insulinomas. In few studies reported so far, endoscopic ultrasound (EUS) has proven to be able to locate lesions. The aim of this study was to compare the performance of computed tomography versus EUS for the detection of insulinomas. Materials and Methods: In a retrospective manner prospectively collected data were analyzed. Patients with hypoglucemia and hyperinsulinemia were included. Diagnostic yield was measured in relationship to sensitivity, specificity, positive predictive value, negative predictive value and accuracy. Surgical specimens were considered the gold standard. Results: Sensitivity, positive predictive value, and accuracy of EUS was 100%, 95.4% and 95.4%, respectively. In the case of CT the sensitivity was 60%, specificity 100%, positive predictive value 100%, negative predictive value 7%, and accuracy were 68%. Conclusions: EUS is useful in the preoperative assessment of patients with hypoglycemia and serum hyperinsulinemia. PMID:25789285

  10. Endoscopic ultrasound guided fine needle tissue acquisition: Where we stand in 2013?

    PubMed Central

    Karadsheh, Zeid; Al-Haddad, Mohammad

    2014-01-01

    Since its introduction, endoscopic ultrasound (EUS) guided fine needle aspiration and fine needle biopsy have become an indispensable tool for the diagnosis of lesions within the gastrointestinal tract and surrounding organs. It has proved to be an effective diagnostic method with high accuracy and low complication rates. Several factors can influence the accuracy and the diagnostic yield of this procedure including experience of the endosonographer, availability of onsite cytopathology services, the method of cytopathology preparation, the location and physical characteristics of the lesion, sampling techniques and the type and size of the needle used. In this review we will outline the recent studies evaluating EUS-guided tissue acquisition and will provide practical recommendations to maximize tissue yield. PMID:24605016

  11. Endoscopic ultrasound-guided fine-needle aspiration in the diagnosis of adrenal lesions

    PubMed Central

    Patil, Rashmee; Ona, Mel A.; Papafragkakis, Charilaos; Duddempudi, Sushil; Anand, Sury; Jamil, Laith H.

    2016-01-01

    The use of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) appears to be a safe and feasible means of confirming or excluding malignancy in the adrenal glands. EUS-FNA with biopsy of suspicious masses in either adrenal gland allows for assessment of these lesions while keeping complications relatively rare. The main advantages of EUS-FNA are that it can be done as an outpatient procedure, with good results, minimal morbidity, and a short hospital stay. Nevertheless, EUS-FNA of adrenal masses should be indicated only in selected cases, in which there is potential to either decrease unnecessary treatment or guide therapy in cancer patients by aiding in either staging of malignancy or treatment of recurrence.v PMID:27366030

  12. The Role of Endoscopic Ultrasound in the Diagnosis and Management of Primary Gastric Lymphoma

    PubMed Central

    Schizas, Dimitrios; Ntanasis-Stathopoulos, Ioannis; Tsilimigras, Diamantis I.; Scotiniotis, Ilias

    2017-01-01

    Endoscopic ultrasound (EUS) is considered a valuable diagnostic tool during the workup of malignant gastric lesions, including primary gastric lymphomas (PGL). Although endoscopy combined with multiple biopsies remains essential in the establishment of PGL diagnosis, EUS utilization in locoregional disease staging has been well documented in the literature. Data also support the possible role of EUS in prediction of response to first-line treatment, that is, Helicobacter pylori eradication. However, its application in the posttreatment setting remains problematic, since concordance rates between endosonography and histology findings during follow-up seem to vary substantially. The aim of the present review is to summarize all available data regarding the role of EUS in the management of PGL. PMID:28400819

  13. Glomus tumor of the stomach: cytologic diagnosis by endoscopic ultrasound-guided fine-needle aspiration.

    PubMed

    Debol, Steven M; Stanley, Michael W; Mallery, Shawn; Sawinski, Elizabeth; Bardales, Ricardo H

    2003-06-01

    The glomus tumor is usually a benign solitary neoplasm that arises from modified smooth muscle cells of the glomus body, a type of neuromyoarterial receptor that plays a role in the regulation of arterial blood flow. We report a case of gastric glomus tumor diagnosed by endoscopic ultrasound-guided fine-needle aspiration. Smears exhibited groups of cohesive, uniform, small, round to polygonal cells with scant cytoplasm, indistinct cell borders, and round, hyperchromatic nuclei with homogeneous chromatin. The cell block contained fragments of cells with similar morphologic features and immunohistochemical staining exhibited positivity for smooth muscle actin and vimentin. The diagnosis was confirmed by the surgically resected specimen. Ultrastructural examination revealed prominent pinocytotic vesicles lining the plasmalemma. In this report, we discuss the differential diagnosis of gastric glomus tumor and compare the cytologic features of this case with two others reported in the literature. Copyright 2003 Wiley-Liss, Inc.

  14. Role of contrast harmonic-endoscopic ultrasound in pancreatic cystic lesions

    PubMed Central

    Serrani, Marta; Lisotti, Andrea; Caletti, Giancarlo; Fusaroli, Pietro

    2017-01-01

    Incidental pancreatic cysts (PCs) are frequently encountered in the general population often in asymptomatic patients who undergo imaging tests to investigate unrelated conditions. The detection of a PC poses a significant clinical dilemma, as the differential diagnosis is quite broad ranging from benign to malignant conditions. Endoscopic ultrasound (EUS) with fine-needle aspiration (FNA) has been reported to be an accurate tool in the differential diagnosis; however, its sensitivity is suboptimal and false negative results do occur. Contrast harmonic EUS (CH-EUS) was demonstrated to be a useful tool to investigate pancreatic solid lesions to differentiate between benign and malignant ones. In the setting of PCs, CH-EUS could help identify areas of malignant growth inside the cystic cavities. Several studies have reported promising results showing malignant areas in PCs as hyperenhanced lesions. Confirmation of malignancy can then be obtained by FNA, which should be precisely targeted according to the findings of the contrast harmonic study. PMID:28218197

  15. Esophageal seeding after endoscopic ultrasound-guided fine-needle aspiration of a mediastinal tumor.

    PubMed

    Yokoyama, Kensuke; Ushio, Jun; Numao, Norikatsu; Tamada, Kiichi; Fukushima, Noriyoshi; Kawarai Lefor, Alan; Yamamoto, Hironori

    2017-09-01

    Background and study aims  Tumor seeding after endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is rare. A 53-year-old man underwent transesophageal EUS-FNA for diagnosis of a 6-cm mass in the mediastinum as seen by computed tomography (CT). Four weeks later, repeat CT scan revealed a mass in the esophageal wall. Upper gastrointestinal endoscopy confirmed a lesion in the mid-esophagus, which was biopsied and found to be consistent with needle tract seeding after EUS-FNA. Tumor seeding in the gastrointestinal wall or peritoneum after EUS-FNA is rare, but may adversely affect the prognosis. Indications for EUS-FNA must be carefully considered.

  16. Current status of endoscopic ultrasound for the upper gastrointestinal tract in Asia.

    PubMed

    Yoshinaga, Shigetaka; Hilmi, Ida Normiha; Kwek, Boon Eu Andrew; Hara, Kazuo; Goda, Kenichi

    2015-04-01

    We summarize the current status of endoscopic ultrasound (EUS) for the upper gastrointestinal (GI) tract solely in Asia, focusing on the staging of superficial cancers and the diagnosis of submucosal tumors (SMT), by analysis of questionnaire responses and a literature review. EUS for assessing the depth of superficial cancers of the upper GI tract is useful; however, evidence is lacking to support that EUS is superior to other modalities. The current status of EUS varies across different Asian countries, and standardization of the methods used both during the procedure and for depth subclassification is necessary to evaluate the diagnostic accuracy. Although EUS alone is limited in the diagnosis of SMT, EUS-guided fine-needle aspiration is an effective and safe diagnostic tool. Although there is a role for EUS, there are still many limitations both technically and in terms of accessibility. © 2014 The Authors. Digestive Endoscopy © 2014 Japan Gastroenterological Endoscopy Society.

  17. Combining endoscopic ultrasound with Time-Of-Flight PET: The EndoTOFPET-US Project

    NASA Astrophysics Data System (ADS)

    Frisch, Benjamin

    2013-12-01

    The EndoTOFPET-US collaboration develops a multimodal imaging technique for endoscopic exams of the pancreas or the prostate. It combines the benefits of high resolution metabolic imaging with Time-Of-Flight Positron Emission Tomography (TOF PET) and anatomical imaging with ultrasound (US). EndoTOFPET-US consists of a PET head extension for a commercial US endoscope and a PET plate outside the body in coincidence with the head. The high level of miniaturization and integration creates challenges in fields such as scintillating crystals, ultra-fast photo-detection, highly integrated electronics, system integration and image reconstruction. Amongst the developments, fast scintillators as well as fast and compact digital SiPMs with single SPAD readout are used to obtain the best coincidence time resolution (CTR). Highly integrated ASICs and DAQ electronics contribute to the timing performances of EndoTOFPET. In view of the targeted resolution of around 1 mm in the reconstructed image, we present a prototype detector system with a CTR better than 240 ps FWHM. We discuss the challenges in simulating such a system and introduce reconstruction algorithms based on graphics processing units (GPU).

  18. Endoscopic Ultrasound of the Upper Gastrointestinal Tract and Mediastinum: Diagnosis and Therapy

    SciTech Connect

    Prasad, Priyajit; Wittmann, Johannes; Pereira, Stephen P.

    2006-12-15

    Endoscopic ultrasound (EUS) has developed significantly over the last two decades and has had a considerable impact on the imaging and staging of mass lesions within or in close proximity to the gastrointestinal (GI) tract. In conjunction with conventional imaging such as helical computed tomography and magnetic resonance imaging, the indications for EUS include (1) differentiating between benign and malignant lesions of the mediastinum and upper GI tract, (2) staging malignant tumors of the lung, esophagus, stomach, and pancreas prior to surgery or oncological treatment, (3) excluding common bile duct stones before laparoscopic cholecystectomy, thereby avoiding the need for endoscopic retrograde cholangiopancreatography (ERCP) in some patients, and (4) assessing suspected lesions that are either equivocal or not seen on conventional imaging. In recent years, EUS has charted a course similar to that taken by ERCP, evolving from a purely diagnostic modality to one that is interventional and therapeutic. These indications include (5) obtaining a tissue diagnosis by EUS-guided fine-needle aspiration or trucut-type needle biopsy and (6) providing therapy such as coeliac plexus neurolysis and pancreatic pseudocyst drainage-in many cases, more accurately and safely than conventional techniques. Emerging investigational techniques include EUS-guided enteric anastomosis formation and fine-needle injection therapy for malignant disease.

  19. Endoscopic ultrasound criteria to predict the need for intervention in pancreatic necrosis

    PubMed Central

    2012-01-01

    Background The natural course and treatment strategies for asymptomatic or oligosymptomatic pancreatic necrosis are still poorly defined. The aim of this retrospective study was to establish criteria for the need of intervention in patients with pancreatic necrosis. Methods A total of 31 consecutive patients (18 male, median age 58 yrs.) diagnosed with pancreatic necrosis by endoscopic ultrasound, in whom a decision for initial conservative treatment was made, were followed for the need of interventions such as endoscopic or surgical intervention, or death. Results After a median follow-up of 243 days, 21 patients remained well without intervention and in 10 patients an endpoint event occurred. In a multivariate logistic regression analysis of the clinical and endosonographic parameters, liquid content was the single independent predictor for intervention (p = 0.0006). The presence of high liquid content in the pancreatic necrosis resulted in a 64% predicted endpoint risk as compared to 2% for solid necrosis. Conclusions Pancreatic necrotic cavities with high liquid content are associated with a high risk of complications. Therefore, close clinical monitoring is needed and early elective intervention might be considered in these patients. PMID:22584080

  20. Endoscopic ultrasound-guided treatments: Are we getting evidence based - a systematic review

    PubMed Central

    Fabbri, Carlo; Luigiano, Carmelo; Lisotti, Andrea; Cennamo, Vincenzo; Virgilio, Clara; Caletti, Giancarlo; Fusaroli, Pietro

    2014-01-01

    The continued need to develop less invasive alternatives to surgical and radiologic interventions has driven the development of endoscopic ultrasound (EUS)-guided treatments. These include EUS-guided drainage of pancreatic fluid collections, EUS-guided necrosectomy, EUS-guided cholangiography and biliary drainage, EUS-guided pancreatography and pancreatic duct drainage, EUS-guided gallbladder drainage, EUS-guided drainage of abdominal and pelvic fluid collections, EUS-guided celiac plexus block and celiac plexus neurolysis, EUS-guided pancreatic cyst ablation, EUS-guided vascular interventions, EUS-guided delivery of antitumoral agents and EUS-guided fiducial placement and brachytherapy. However these procedures are technically challenging and require expertise in both EUS and interventional endoscopy, such as endoscopic retrograde cholangiopancreatography and gastrointestinal stenting. We undertook a systematic review to record the entire body of literature accumulated over the past 2 decades on EUS-guided interventions with the objective of performing a critical appraisal of published articles, based on the classification of studies according to levels of evidence, in order to assess the scientific progress made in this field. PMID:25024600

  1. An anthropomorphic tissue-mimicking phantom of the oesophagus for endoscopic ultrasound.

    PubMed

    Inglis, Scott; Ramnarine, Kumar V; Plevris, John N; McDicken, W Norman

    2006-02-01

    This study details the design and construct of an anthropomorphic phantom of the oesophagus suitable for use with endoscopic ultrasound (EUS) and 3-D volume measurements. The phantom was constructed using agar-based tissue-mimicking material (TMM) of different acoustical properties to simulate various anatomical and pathologic features. The acoustical properties were measured with a scanning acoustical macroscope. An Olympus GF-UM200 echo-endoscope and digital position measurement arm were used to scan the phantom at 7.5 and 12 MHz. Comparative dimensional measurements were performed on the phantom via 2-D and 3-D EUS. TMM attenuation varied between 0.1 and 0.5 dB/cm.MHz. Backscatter power, relative to normal TMM, was from 0 to -12.2 dB, with an average speed of sound of 1537 +/- 1.9 m/s. Measurements of objects within the phantom by 2-D and 3-D EUS had mean errors of 8% and 2.2%, respectively. The construction of the anthropomorphic EUS phantom facilitated EUS training and research and development studies.

  2. PMN-PT single crystal for endoscopic ultrasound 2D array application

    NASA Astrophysics Data System (ADS)

    Zhu, Yuhang; Liang, Huageng; Zhu, Benpeng; Zhou, Dan; Yang, Xiaofei

    2017-03-01

    Based on lead magnesium niobate-lead titanate single crystal, a 24 × 24 row-column addressing endoscopic two-dimensional array has been successfully fabricated using novel flanged electrodes and "semi-kerf" technologies. Each row/column array element was measured to have an electromechanical coupling coefficient of 0.81, a center frequency of 5MHz, and a fractional bandwidth of approximately 88% at -6 dB. Of particular significance was that the lead magnesium niobate-lead titanate element exhibits much higher sensitivity compared with lead zirconate titanate-based 2D arrays with similar operational frequency and element area. According to the Field II simulated results, although the obtained beamwidth at -6 dB was a little inferior to that of the fully sampled 24 × 24 two-dimensional array, it is believed that the beamwidth can be improved by appropriately increasing the element number. These results demonstrated that the lead magnesium niobate-lead titanate single-crystal 2D array is a promising candidate for real-time three-dimensional endoscopic ultrasound imaging.

  3. Efficiency of B-mode Ultrasound and Strain Elastography in Differentiating Between Benign and Malignant Cervical Lymph Nodes.

    PubMed

    Turgut, Eser; Celenk, Cetin; Tanrivermis Sayit, Asli; Bekci, Tumay; Gunbey, Hediye Pinar; Aslan, Kerim

    2017-09-01

    The purpose of this study was to evaluate the diagnostic accuracy and efficiency of ultrasonography (US), especially when combined with strain elastography (SE), in differentiating between benign and malignant cervical lymph nodes (LNs). Forty-one LNs were examined by B-mode US, power Doppler US, and SE. The following imaging features were analyzed: shape, echogenicity, echogenic hilum, calcification, intranodal vascular pattern, elasticity scores (5 categories), and strain ratio. The average strain ratio was calculated as the mean strain of the adjacent sternocleidomastoid muscle divided by the mean strain of the target LN. The results of the US and SE features were compared with the histopathologic findings. The imaging features that were significantly associated with malignant LNs were an increased short-to-long axis diameter ratio, abnormal or absence of hilum, microcalcification, type 2-3-4 vascularity, 3-4-5 elasticity scores, and a high level of strain ratio (P < 0.05). The cutoff value of the strain index was detected as 1.18. According to this, there was a significant difference (P = 0.004) in the strain index between benign and malignant LNs. Strain elastography is useful in differentiating between benign and malignant cervical LNs, thereby informing decisions to perform a biopsy and/or surgery, and facilitating follow-up.

  4. Magnetic resonance elastography for the noninvasive staging of liver fibrosis.

    PubMed

    Huwart, Laurent; Sempoux, Christine; Vicaut, Eric; Salameh, Najat; Annet, Laurence; Danse, Etienne; Peeters, Frank; ter Beek, Leon C; Rahier, Jacques; Sinkus, Ralph; Horsmans, Yves; Van Beers, Bernard E

    2008-07-01

    The purpose of our study was to prospectively compare the success rate and diagnostic accuracy of magnetic resonance elastography, ultrasound elastography, and aspartate aminotransferase to platelets ratio index (APRI) measurements for the noninvasive staging of fibrosis in patients with chronic liver disease. We performed a prospective blind comparison of magnetic resonance elastography, ultrasound elastography, and APRI in a consecutive series of patients who underwent liver biopsy for chronic liver disease in a university-based hospital. Histopathologic staging of liver fibrosis according to the METAVIR scoring system served as the reference. A total of 141 patients were assessed. The technical success rate of magnetic resonance elastography was higher than that of ultrasound elastography (133/141 [94%] vs 118/141 [84%]; P = .016). Magnetic and ultrasound elastography, APRI measurements, and histopathologic analysis of liver biopsy specimens were technically successful in 96 patients. The areas under the receiver operating characteristic curves of magnetic resonance elasticity (0.994 for F >or= 2; 0.985 for F >or= 3; 0.998 for F = 4) were larger (P < .05) than those of ultrasound elasticity, APRI, and the combination of ultrasound elasticity and APRI (0.837, 0.709, and 0.849 for F >or= 2; 0.906, 0.816, and 0.936 for F >or= 3; 0.930, 0.820, and 0.944 for F = 4, respectively). Magnetic resonance elastography has a higher technical success rate than ultrasound elastography and a better diagnostic accuracy than ultrasound elastography and APRI for staging liver fibrosis.

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

    PubMed Central

    Lachter, Jesse

    2014-01-01

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

  6. Results from the commissioning of a multi-modal endoscope for ultrasound and time of flight PET

    SciTech Connect

    Bugalho, Ricardo

    2015-07-01

    The EndoTOFPET-US collaboration has developed a multi-modal imaging system combining Ultrasound with Time-of-Flight Positron Emission Tomography into an endoscopic imaging device. The objective of the project is to obtain a coincidence time resolution of about 200 ps FWHM and to achieve about 1 mm spatial resolution of the PET system, while integrating all the components in a very compact detector suitable for endoscopic use. This scanner aims to be exploited for diagnostic and surgical oncology, as well as being instrumental in the clinical test of new biomarkers especially targeted for prostate and pancreatic cancer. (authors)

  7. Right adrenal gland prospective evaluation through transgastric endoscopic ultrasound: an alternative approach

    PubMed Central

    Figueiredo, Pedro C.; Pinto-Marques, Pedro; Almeida, Ines; Gomes, Pedro C.; Serra, David

    2016-01-01

    Background and aims: Endoscopic ultrasound (EUS) guided right adrenal gland (RAG) evaluation is frequently unsuccessful and, when feasible, requires a cumbersome maneuver through the duodenum. In our experience, the use of a recent ultrasound platform has enabled transgastric detection of the RAG with a simple maneuver. The aim of this study was to determine the RAG transgastric EUS detection rate and identify predictive factors for failure. Methods: Consecutive patients referred to EUS in a single center were prospectively included over a 6-month period. Success was defined as RAG transgastric EUS detection within 180 seconds. Logistic regression analysis was used to assess factors associated with failure. Results: Among 100 patients, the success rate for RAG transgastric EUS detection was 75 %, with a median maneuver duration of 45 seconds [interquartile range, 25 – 70 seconds]. Two incidental RAG lesions were detected. Of possible demographic and anthropometric predictive factors for failure, only age (OR 1.04; P = 0.04) was statistically significant on multivariate analysis. Conclusions: The transgastric EUS approach for RAG detection is simple, fast and effective. PMID:27853745

  8. Venous elastography: validation of a novel high-resolution ultrasound method for measuring vein compliance using finite element analysis.

    PubMed

    Biswas, Rohan; Patel, Prashant; Park, Dae W; Cichonski, Thomas J; Richards, Michael S; Rubin, Jonathan M; Hamilton, James; Weitzel, William F

    2010-01-01

    Ultrasonography for the noninvasive assessment of tissue properties has enjoyed widespread success. With the growing emphasis in recent years on arteriovenous fistulae (AVFs) for dialysis vascular access in patients with end-stage renal disease, and on reducing AVF failures, there is increasing interest in ultrasound for the preoperative evaluation of the mechanical and elastic properties of arteries and veins. This study used high-resolution ultrasound with phase-sensitive speckle tracking to obtain in vivo vein elasticity measurements during dilation. The results of this novel ultrasound technique were then compared to a computer model of venous strain. The computer model and ultrasound analysis of the vessel wall demonstrated internally consistent positive and negative longitudinal strain values as the vein wall underwent dilation. These results support further investigation of the use of phase-sensitive speckle tracking for ultrasound venous mapping for preoperative vascular access evaluation.

  9. Contrast-enhanced harmonic endoscopic ultrasound imaging: basic principles, present situation and future perspectives.

    PubMed

    Alvarez-Sánchez, María-Victoria; Napoléon, Bertrand

    2014-11-14

    Over the last decade, the development of stabilised microbubble contrast agents and improvements in available ultrasonic equipment, such as harmonic imaging, have enabled us to display microbubble enhancements on a greyscale with optimal contrast and spatial resolution. Recent technological advances made contrast harmonic technology available for endoscopic ultrasound (EUS) for the first time in 2008. Thus, the evaluation of microcirculation is now feasible with EUS, prompting the evolution of contrast-enhanced EUS from vascular imaging to images of the perfused tissue. Although the relevant experience is still preliminary, several reports have highlighted contrast-enhanced harmonic EUS (CH-EUS) as a promising noninvasive method to visualise and characterise lesions and to differentiate benign from malignant focal lesions. Even if histology remains the gold standard, the combination of CH-EUS and EUS fine needle aspiration (EUS-FNA) can not only render EUS more accurate but may also assist physicians in making decisions when EUS-FNA is inconclusive, increasing the yield of EUS-FNA by guiding the puncture with simultaneous imaging of the vascularity. The development of CH-EUS has also opened up exciting possibilities in other research areas, including monitoring responses to anticancer chemotherapy or to ethanol-induced pancreatic tissue ablation, anticancer therapies based on ultrasound-triggered drug and gene delivery, and therapeutic adjuvants by contrast ultrasound-induced apoptosis. Contrast harmonic imaging is gaining popularity because of its efficacy, simplicity and non-invasive nature, and many expectations are currently resting on this technique. If its potential is confirmed in the near future, contrast harmonic imaging will become a standard practice in EUS.

  10. Contrast-enhanced harmonic endoscopic ultrasound imaging: Basic principles, present situation and future perspectives

    PubMed Central

    Alvarez-Sánchez, María-Victoria; Napoléon, Bertrand

    2014-01-01

    Over the last decade, the development of stabilised microbubble contrast agents and improvements in available ultrasonic equipment, such as harmonic imaging, have enabled us to display microbubble enhancements on a greyscale with optimal contrast and spatial resolution. Recent technological advances made contrast harmonic technology available for endoscopic ultrasound (EUS) for the first time in 2008. Thus, the evaluation of microcirculation is now feasible with EUS, prompting the evolution of contrast-enhanced EUS from vascular imaging to images of the perfused tissue. Although the relevant experience is still preliminary, several reports have highlighted contrast-enhanced harmonic EUS (CH-EUS) as a promising noninvasive method to visualise and characterise lesions and to differentiate benign from malignant focal lesions. Even if histology remains the gold standard, the combination of CH-EUS and EUS fine needle aspiration (EUS-FNA) can not only render EUS more accurate but may also assist physicians in making decisions when EUS-FNA is inconclusive, increasing the yield of EUS-FNA by guiding the puncture with simultaneous imaging of the vascularity. The development of CH-EUS has also opened up exciting possibilities in other research areas, including monitoring responses to anticancer chemotherapy or to ethanol-induced pancreatic tissue ablation, anticancer therapies based on ultrasound-triggered drug and gene delivery, and therapeutic adjuvants by contrast ultrasound-induced apoptosis. Contrast harmonic imaging is gaining popularity because of its efficacy, simplicity and non-invasive nature, and many expectations are currently resting on this technique. If its potential is confirmed in the near future, contrast harmonic imaging will become a standard practice in EUS. PMID:25400439

  11. Design of a phased array for the generation of adaptive radiation force along a path surrounding a breast lesion for dynamic ultrasound elastography imaging.

    PubMed

    Ekeom, Didace; Hadj Henni, Anis; Cloutier, Guy

    2013-03-01

    This work demonstrates, with numerical simulations, the potential of an octagonal probe for the generation of radiation forces in a set of points following a path surrounding a breast lesion in the context of dynamic ultrasound elastography imaging. Because of the in-going wave adaptive focusing strategy, the proposed method is adapted to induce shear wave fronts to interact optimally with complex lesions. Transducer elements were based on 1-3 piezocomposite material. Three-dimensional simulations combining the finite element method and boundary element method with periodic boundary conditions in the elevation direction were used to predict acoustic wave radiation in a targeted region of interest. The coupling factor of the piezocomposite material and the radiated power of the transducer were optimized. The transducer's electrical impedance was targeted to 50 Ω. The probe was simulated by assembling the designed transducer elements to build an octagonal phased-array with 256 elements on each edge (for a total of 2048 elements). The central frequency is 4.54 MHz; simulated transducer elements are able to deliver enough power and can generate the radiation force with a relatively low level of voltage excitation. Using dynamic transmitter beamforming techniques, the radiation force along a path and resulting acoustic pattern in the breast were simulated assuming a linear isotropic medium. Magnitude and orientation of the acoustic intensity (radiation force) at any point of a generation path could be controlled for the case of an example representing a heterogeneous medium with an embedded soft mechanical inclusion.

  12. Acute effects of static stretching on the hamstrings using shear elastic modulus determined by ultrasound shear wave elastography: Differences in flexibility between hamstring muscle components.

    PubMed

    Umegaki, Hiroki; Ikezoe, Tome; Nakamura, Masatoshi; Nishishita, Satoru; Kobayashi, Takuya; Fujita, Kosuke; Tanaka, Hiroki; Ichihashi, Noriaki

    2015-08-01

    Static stretching (SS) with hip flexion and knee extension is often used to stretch the hamstrings. However, it is unclear whether there are the differences in the acute effect of this SS maneuver on flexibility between each component of the hamstrings, namely the semitendinosus (ST), semimembranosus (SM), and biceps femoris (BF) muscles. The aims of this study were to investigate the acute effects of SS on the flexibility of the individual muscle components of the hamstrings, and to examine the difference in the acute effect of SS between these components using shear elastic modulus as the index of muscle flexibility. Twenty healthy men (age, 23.4 ± 2.3 years) volunteered for this study. The shear elastic modulus of the ST, SM and BF muscles were measured using ultrasound shear wave elastography before (PRE) and immediately after (POST) 5 min of SS. Measurements of shear elastic modulus were taken with the knee at 90° (slack position) and 45° (extension position) of flexion. In all muscles, the shear elastic modulus at both knee angles decreased significantly after SS. The percentage change in the shear elastic modulus from PRE to POST in the muscles at 45° of knee flexion was greatest in the SM. These results suggest that SS with hip flexion and knee extension has acute effects on increasing flexibility of the hamstring muscle components, especially the SM muscle. Copyright © 2015. Published by Elsevier Ltd.

  13. Guided waves in pre-stressed hyperelastic plates and tubes: Application to the ultrasound elastography of thin-walled soft materials

    NASA Astrophysics Data System (ADS)

    Li, Guo-Yang; He, Qiong; Mangan, Robert; Xu, Guoqiang; Mo, Chi; Luo, Jianwen; Destrade, Michel; Cao, Yanping

    2017-05-01

    In vivo measurement of the mechanical properties of thin-walled soft tissues (e.g., mitral valve, artery and bladder) and in situ mechanical characterization of thin-walled artificial soft biomaterials in service are of great challenge and difficult to address via commonly used testing methods. Here we investigate the properties of guided waves generated by focused acoustic radiation force in immersed pre-stressed plates and tubes, and show that they can address this challenge. To this end, we carry out both (i) a theoretical analysis based on incremental wave motion in finite deformation theory and (ii) finite element simulations. Our analysis leads to a novel method based on the ultrasound elastography to image the elastic properties of pre-stressed thin-walled soft tissues and artificial soft materials in a non-destructive and non-invasive manner. To validate the theoretical and numerical solutions and demonstrate the usefulness of the corresponding method in practical measurements, we perform (iii) experiments on polyvinyl alcohol cryogel phantoms immersed in water, using the Verasonics V1 System equipped with a L10-5 transducer. Finally, potential clinical applications of the method have been discussed.

  14. Acoustic Radiation Force Impulse Elastography for Efficacy Evaluation after Hepatocellular Carcinoma Radiofrequency Ablation: A Comparative Study with Contrast-Enhanced Ultrasound

    PubMed Central

    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

  15. Quantitative assessment of the supraspinatus tendon on MRI using T2/T2* mapping and shear-wave ultrasound elastography: a pilot study.

    PubMed

    Krepkin, Konstantin; Bruno, Mary; Raya, José G; Adler, Ronald S; Gyftopoulos, Soterios

    2017-02-01

    To determine whether there is an association between T2/T2* mapping and supraspinatus tendon mechanical properties as assessed by shear-wave ultrasound elastography (SWE). This HIPAA-compliant prospective pilot study received approval from our hospital's institutional review board. Eight patients (3 males/5 females; age range 44-72 years) and nine shoulders underwent conventional shoulder MRI, T2/T2* mapping on a 3-T scanner, and SWE. Two musculoskeletal radiologists reviewed the MRI examinations in consensus for evidence of supraspinatus tendon pathology, with tear size measured for full-thickness tears. T2/T2* values and ultrasound shear-wave velocities (SWV) were calculated in three corresponding equidistant regions of interest (ROIs) within the insertional 1-2 cm of the supraspinatus tendon (medial, middle, lateral). Pearson correlation coefficients between T2/T2* values and SWV, as well as among T2, T2*, SWV and tear size, were calculated. There was a significant negative correlation between T2* and SWV in the lateral ROI (r = -0.86, p = 0.013) and overall mean ROI (r = -0.90, p = 0.006). There was significant positive correlation between T2 and measures of tear size in the lateral and mean ROIs (r range 0.71-0.77, p range 0.016-0.034). There was significant negative correlation between SWV and tear size in the middle and mean ROIs (r range -0.79--0.68, p range 0.011-0.046). Our pilot study demonstrated a potential relationship between T2* values and shear wave velocity values in the supraspinatus tendon, a finding that could lead to an improved, more quantitative evaluation of the rotator cuff tendons.

  16. [Assessment of amylase and lipase levels following puncture biopsy and fine needle aspiration guided by endoscopic ultrasound in pancreatic lesions].

    PubMed

    Membrillo-Romero, Alejandro; Gonzalez-Lanzagorta, Rubén; Rascón-Martínez, Dulce María

    2016-12-14

    Puncture biopsy and fine needle aspiration guided by endoscopic ultrasound has been used as an effective technique and is quickly becoming the procedure of choice for diagnosis and staging in patients suspected of having pancreatic cancer. This procedure has replaced retrograde cholangiopancreatography and brush cytology due to its higher sensitivity for diagnosis, and lower risk of complications. To assess the levels of pancreatic enzymes amylase and lipase, after the puncture biopsy and fine needle aspiration guided by endoscopic ultrasound in pancreatic lesions and the frequency of post-puncture acute pancreatitis. A longitudinal and descriptive study of consecutive cases was performed on outpatients submitted to puncture biopsy and fine needle aspiration guided by endoscopic ultrasound in pancreatic lesions. Levels of pancreatic enzymes such as amylase and lipase were measured before and after the pancreatic puncture. Finally we documented post-puncture pancreatitis cases. A total of 100 patients who had been diagnosed with solid and cystic lesions were included in the study. Significant elevation was found at twice the reference value for lipase in 5 cases (5%) and for amylase in 2 cases (2%), none had clinical symptoms of acute pancreatitis. Eight (8%) of patients presented with mild nonspecific pain with no enzyme elevation compatible with pancreatitis. Pancreatic biopsy needle aspiration guided by endoscopic ultrasound was associated with a low rate of elevated pancreatic enzymes and there were no cases of post-puncture pancreatitis. Copyright © 2016 Academia Mexicana de Cirugía A.C. Publicado por Masson Doyma México S.A. All rights reserved.

  17. [Contribution of endoscopic ultrasound to the diagnosis of pancreatic metastases from renal carcinoma. Apropos of two cases].

    PubMed

    Repiso, Alejandro; Gómez-Rodríguez, Rafael; Aso, Sonsoles; Domper, Francisco; Buendía, Encarnación; González de Frutos, Concepción; Pérez-Grueso, María José; Rodríguez-Merlo, Rufo; Carrobles, José María

    2007-03-01

    Pancreatic metastases represent 2% of pancreatic tumors. The neoplasms most frequently metastasizing to the pancreas are breast, lung, melanoma and kidney tumors. We present the cases of two patients with pancreatic metastases from renal carcinoma diagnosed 4 and 8 years after the diagnosis and surgical treatment of the primary renal tumor. In both patients, endoscopic ultrasound was useful in the detection and characterization of these pancreatic lesions and allowed fine-needle aspiration for cytological study to be performed.

  18. Clear cell neuroendocrine tumor of pancreas: Endoscopic Ultrasound-guided fine needle aspiration diagnosis of an uncommon variant

    PubMed Central

    Kaur, Gagandeep; Bakshi, Pooja; Singla, Vikas; Verma, Kusum

    2016-01-01

    The cytomorphologic features of clear cell neuroendocrine tumor of pancreas have been rarely reported in cytology literature. The cytomorphology of this rare variant mimics many primary and metastatic clear cell tumors of the pancreas. However, a precise cytological diagnosis can be rendered by awareness of this entity and judicious use of immunohistochemistry. We report one such case in a young woman diagnosed on endoscopic ultrasound fine needle aspiration. The tumor cells showed positive staining with synaptophysin, chromogranin, and also with inhibin. PMID:27081395

  19. Intrasurgical dignity assessment of hepatic tumors using semi-quantitative strain elastography and contrast-enhanced ultrasound for optimisation of liver tumor surgery.

    PubMed

    Platz Batista da Silva, N; Schauer, M; Hornung, M; Lang, S; Beyer, L P; Wiesinger, I; Stroszczynski, C; Jung, E M

    2016-01-01

    To evaluate the efficacy of strain elastography (SE) using semi-quantitative measurement methods compared to constrast enhanced ultrasound during liver tumor surgery (Io-CEUS) for dignity assessment of focal liver lesions(FLL). Prospective data acquisition and retrospective analysis of US data of 100 patients (116 lesions) who underwent liver tumor surgery between 10/2010 and 03/2016. Retrospective reading of SE color patterns was performed establishing groups depending on dominant color (>50% blue = stiff, inhomogenous, >50% yellow/red/green = soft tissue). Semi-quantitative analysis was performed by Q-analysis based on a scale from 0 (soft) to 6 (stiff). 2 ROIs were placed centrally, 5 ROIs in the lesion's surrounding tissue. Io-CEUS was performed by bolus injection of 5-10 ml sulphurhexaflourid microbubbles evaluating wash-in- and -out- kinetics in arterial, portal venous and late phase. Histopathology after surgical resection served as goldstandard. 100 patients (m: 65, f: 35, mean age 60.5 years) with 116 liver lesions were included. Lesion's size ranged from 0.5 to 8.4 cm (mean 2.42 cm SD±1.44 cm). Postoperative histology showed 105 malignant and 11 benign lesions. Semi-quantitative analysis showed central indurations of >2.5 in 76/105 cases suggesting malignancy. 7 benign lesions displayed no central indurations correctly characterized benign by SE. ROC-analysis and Youden index showed a sensitivity of 72.4% and specificity of 63.6% assuming a cut-off of 2.5. Io-CEUS correctly characterized 103/105 as malignant. Sensitivity was 98%, specificity 72.7%. Strain elastography is a valuable tool for non-invasive characterization of FLLs. Semi-quantitative intratumoral stiffness values of >2.5 suggested malignancy. However, sensitivity of Io-CEUS in detecting malignant lesions was higher compared to SE. In conclusion SE should be considered for routine use during intraoperative US in addition to Io-CEUS for optimization of curative liver surgery.

  20. Endoscopic ultrasound sedation in the United Kingdom: Is life without propofol tolerable?

    PubMed Central

    Campbell, Jennifer Anne; Irvine, Andrew James; Hopper, Andrew Derek

    2017-01-01

    There is compelling evidence to support the quality, cost effectiveness and safety profile of non-anesthesiologist-administered propofol for endoscopic ultrasound (EUS). However in the United Kingdom, it is recommended that the administration and monitoring of propofol sedation for endoscopic procedures should be the responsibility of a dedicated and appropriately trained anaesthetist only. The majority of United Kingdom EUS procedures are performed with opiate and benzodiazepine sedation rather than anaesthetist led propofol lists due to anaesthetist resource availability. We sought to prospectively determine the tolerability and safety of EUS with benzodiazepine and opiate sedation in single United Kingdom centre. Two hundred consecutive patients undergoing either EUS or oesophago-gastroduodenoscopy (OGD) with conscious sedation were prospectively recruited with a 1:1 enrolment ratio. Patients completed questionnaires pre and post procedure detailing anticipated and actual pain experienced on a 1-10 visual analogue scale. Demographics, procedure duration, sedation doses and willingness to repeat the procedure were also recorded. EUS procedures lasted significantly longer than OGDs (15 min vs 6 min, P < 0.0001), however, there was no difference in anticipated pain scores between the groups (EUS 3.37/10 vs OGD 3.47/10, P = 0.46). Pain scores indicated EUS was better tolerated than OGD (1.16/10 vs 1.88/10, P = 0.03) although higher doses of sedation were used for EUS procedures. There were no complications identified in either group. We feel our study demonstrates that the tolerability of EUS with opiate and benzodiazepine sedation is acceptable. PMID:28210094

  1. Is endoscopic ultrasound examination necessary in the management of esophageal cancer?

    PubMed Central

    DaVee, Tomas; Ajani, Jaffer A; Lee, Jeffrey H

    2017-01-01

    Despite substantial efforts at early diagnosis, accurate staging and advanced treatments, esophageal cancer (EC) continues to be an ominous disease worldwide. Risk factors for esophageal carcinomas include obesity, gastroesophageal reflux disease, hard-alcohol use and tobacco smoking. Five-year survival rates have improved from 5% to 20% since the 1970s, the result of advances in diagnostic staging and treatment. As the most sensitive test for locoregional staging of EC, endoscopic ultrasound (EUS) influences the development of an optimal oncologic treatment plan for a significant minority of patients with early cancers, which appropriately balances the risks and benefits of surgery, chemotherapy and radiation. EUS is costly, and may not be available at all centers. Thus, the yield of EUS needs to be thoughtfully considered for each patient. Localized intramucosal cancers occasionally require endoscopic resection (ER) for histologic staging or treatment; EUS evaluation may detect suspicious lymph nodes prior to exposing the patient to the risks of ER. Although positron emission tomography (PET) has been increasingly utilized in staging EC, it may be unnecessary for clinical staging of early, localized EC and carries the risk of false-positive metastasis (over staging). In EC patients with evidence of advanced disease, EUS or PET may be used to define the radiotherapy field. Multimodality staging with EUS, cross-sectional imaging and histopathologic analysis of ER, remains the standard-of-care in the evaluation of early esophageal cancers. Herein, published data regarding use of EUS for intramucosal, local, regional and metastatic esophageal cancers are reviewed. An algorithm to illustrate the current use of EUS at The University of Texas MD Anderson Cancer Center is presented. PMID:28223720

  2. Endoscopic ultrasound sedation in the United Kingdom: Is life without propofol tolerable?

    PubMed

    Campbell, Jennifer Anne; Irvine, Andrew James; Hopper, Andrew Derek

    2017-01-21

    There is compelling evidence to support the quality, cost effectiveness and safety profile of non-anesthesiologist-administered propofol for endoscopic ultrasound (EUS). However in the United Kingdom, it is recommended that the administration and monitoring of propofol sedation for endoscopic procedures should be the responsibility of a dedicated and appropriately trained anaesthetist only. The majority of United Kingdom EUS procedures are performed with opiate and benzodiazepine sedation rather than anaesthetist led propofol lists due to anaesthetist resource availability. We sought to prospectively determine the tolerability and safety of EUS with benzodiazepine and opiate sedation in single United Kingdom centre. Two hundred consecutive patients undergoing either EUS or oesophago-gastroduodenoscopy (OGD) with conscious sedation were prospectively recruited with a 1:1 enrolment ratio. Patients completed questionnaires pre and post procedure detailing anticipated and actual pain experienced on a 1-10 visual analogue scale. Demographics, procedure duration, sedation doses and willingness to repeat the procedure were also recorded. EUS procedures lasted significantly longer than OGDs (15 min vs 6 min, P < 0.0001), however, there was no difference in anticipated pain scores between the groups (EUS 3.37/10 vs OGD 3.47/10, P = 0.46). Pain scores indicated EUS was better tolerated than OGD (1.16/10 vs 1.88/10, P = 0.03) although higher doses of sedation were used for EUS procedures. There were no complications identified in either group. We feel our study demonstrates that the tolerability of EUS with opiate and benzodiazepine sedation is acceptable.

  3. Is endoscopic ultrasound examination necessary in the management of esophageal cancer?

    PubMed

    DaVee, Tomas; Ajani, Jaffer A; Lee, Jeffrey H

    2017-02-07

    Despite substantial efforts at early diagnosis, accurate staging and advanced treatments, esophageal cancer (EC) continues to be an ominous disease worldwide. Risk factors for esophageal carcinomas include obesity, gastroesophageal reflux disease, hard-alcohol use and tobacco smoking. Five-year survival rates have improved from 5% to 20% since the 1970s, the result of advances in diagnostic staging and treatment. As the most sensitive test for locoregional staging of EC, endoscopic ultrasound (EUS) influences the development of an optimal oncologic treatment plan for a significant minority of patients with early cancers, which appropriately balances the risks and benefits of surgery, chemotherapy and radiation. EUS is costly, and may not be available at all centers. Thus, the yield of EUS needs to be thoughtfully considered for each patient. Localized intramucosal cancers occasionally require endoscopic resection (ER) for histologic staging or treatment; EUS evaluation may detect suspicious lymph nodes prior to exposing the patient to the risks of ER. Although positron emission tomography (PET) has been increasingly utilized in staging EC, it may be unnecessary for clinical staging of early, localized EC and carries the risk of false-positive metastasis (over staging). In EC patients with evidence of advanced disease, EUS or PET may be used to define the radiotherapy field. Multimodality staging with EUS, cross-sectional imaging and histopathologic analysis of ER, remains the standard-of-care in the evaluation of early esophageal cancers. Herein, published data regarding use of EUS for intramucosal, local, regional and metastatic esophageal cancers are reviewed. An algorithm to illustrate the current use of EUS at The University of Texas MD Anderson Cancer Center is presented.

  4. Real-time 3-d intracranial ultrasound with an endoscopic matrix array transducer.

    PubMed

    Light, Edward D; Mukundan, Srinivasan; Wolf, Patrick D; Smith, Stephen W

    2007-08-01

    A transducer originally designed for transesophageal echocardiography (TEE) was adapted for real-time volumetric endoscopic imaging of the brain. The transducer consists of a 36 x 36 array with an interelement spacing of 0.18 mm. There are 504 transmitting and 252 receive channels placed in a regular pattern in the array. The operating frequency is 4.5 MHz with a -6 dB bandwidth of 30%. The transducer is fabricated on a 10-layer flexible circuit from Microconnex (Snoqualmie, WA, USA). The purpose of this study is to evaluate the clinical feasibility of real-time 3-D intracranial ultrasound with this device. The Volumetrics Medical Imaging (Durham, NC, USA) 3-D scanner was used to obtain images in a canine model. A transcalvarial acoustic window was created under general anesthesia in the animal laboratory by placing a 10-mm burr hole in the high parietal calvarium of a 50-kg canine subject. The burr-hole was placed in a left parasagittal location to avoid the sagittal sinus, and the transducer was placed against the intact dura mater for ultrasound imaging. Images of the lateral ventricles were produced, including real-time 3-D guidance of a needle puncture of one ventricle. In a second canine subject, contrast-enhanced 3-D Doppler color flow images were made of the cerebral vessels including the complete Circle of Willis. Clinical applications may include real-time 3-D guidance of cerebrospinal fluid extraction from the lateral ventricles and bedside evaluation of critically ill patients where computed tomography and magnetic resonance imaging techniques are unavailable.

  5. Combination of two-dimensional shear wave elastography with ultrasound breast imaging reporting and data system in the diagnosis of breast lesions: a new method to increase the diagnostic performance.

    PubMed

    Li, Dan-Dan; Xu, Hui-Xiong; Guo, Le-Hang; Bo, Xiao-Wan; Li, Xiao-Long; Wu, Rong; Xu, Jun-Mei; Zhang, Yi-Feng; Zhang, Kun

    2016-09-01

    To evaluate the diagnostic performance of a new method of combined two-dimensional shear wave elastography (i.e. virtual touch imaging quantification, VTIQ) and ultrasound (US) Breast Imaging Reporting and Data System (BI-RADS) in the differential diagnosis of breast lesions. From September 2014 to December 2014, 276 patients with 296 pathologically proven breast lesions were enrolled in this study. The conventional US images were interpreted by two independent readers. The diagnosis performances of BI-RADS and combined BI-RADS and VTIQ were evaluated, including the area under the receiver operating characteristic curve (AUROC), sensitivity and specificity. Observer consistency was also evaluated. Pathologically, 212 breast lesions were benign and 84 were malignant. Compared with BI-RADS alone, the AUROCs and specificities of the combined method for both readers increased significantly (AUROC: 0.862 vs. 0.693 in reader 1, 0.861 vs. 0.730 in reader 2; specificity: 91.5 % vs. 38.7 % in reader 1, 94.8 % vs. 47.2 % in reader 2; all P < .05). The Kappa value between the two readers for BI-RADS assessment was 0.614, and 0.796 for the combined method. The combined VTIQ and BI-RADS had a better diagnostic performance in the diagnosis of breast lesions in comparison with BI-RADS alone. • Combination of conventional ultrasound and elastography distinguishes breast cancers more effectively. • Combination of conventional ultrasound and elastography increases observer consistency. • BI-RADS weights more than the 2D-SWE with an increase in malignancy probability.

  6. Endoscopic Ultrasound-Guided Vascular Therapy: The Present and the Future

    PubMed Central

    Hall, Philip S.J.; Teshima, Christopher; May, Gary R.; Mosko, Jeffrey D.

    2017-01-01

    Endoscopic ultrasound (EUS) offers access to many intra-abdominal vessels that until now have only been accessible to the surgeon and interventional radiologist. In addition to assisting with diagnostics, this unique access offers the potential for therapeutic intervention for a host of indications. To date, this has had the most clinical impact in the treatment of gastroesophageal varices, with EUS-guided coil and glue application growing in use worldwide. Although randomised controlled trial data is lacking, we discuss the growing body of literature behind EUS-guided therapy in the management of varices. EUS has also been used in specialized centres to assist in non-variceal gastrointestinal bleeding. The treatment of bleeding from Dieulafoy lesions, tumours and pancreatic pseudoaneurysms has all been described. The potential applications of EUS have also extended to the placement of portal vein stents and porto-systemic shunts in animal models. As medicine continues to move to increasingly less invasive interventions, EUS-guided therapies offer substantial promise for the safe and effective delivery of targeted treatment for a widening array of vascular disorders. PMID:28391673

  7. Endoscopic ultrasound-guided gastrojejunostomy with a lumen-apposing metal stent: a multicenter, international experience

    PubMed Central

    Tyberg, Amy; Perez-Miranda, Manuel; Sanchez-Ocaña, Ramon; Peñas, Irene; de la Serna, Carlos; Shah, Janak; Binmoeller, Kenneth; Gaidhane, Monica; Grimm, Ian; Baron, Todd; Kahaleh, Michel

    2016-01-01

    Background: Surgical gastrojejunostomy and enteral self-expanding metal stents are efficacious for the management of gastric outlet obstruction but limited by high complication rates and short-term efficacy. Endoscopic ultrasound-guided gastrojejunostomy (EUS-GJ) is a novel alternative option. Patients and methods: Patients who underwent EUS-GJ between March 2014 and September 2015 as part of a prospective multicenter registry at four academic centers in two countries were included. Technical success was defined as successful placement of a gastrojejunal lumen-apposing metal stent. Clinical success was defined as the ability of the patient to tolerate an oral diet. Post-procedural adverse events were recorded. Results: The study included 26 patients, of whom 11 (42 %) were male. Technical success was achieved in 24 patients (92 %). Clinical success was achieved in 22 patients (85 %). Of the 4 patients in whom clinical success was not achieved, 2 had persistent nausea and vomiting despite a patent EUS-GJ and required enteral feeding for nutrition, 1 died before the initiation of an oral diet, and 1 underwent surgery for suspected perforation. Adverse events, including peritonitis, bleeding, and surgery, occurred in 3 patients (11.5 %). Conclusion: EUS-GJ is an emerging procedure that has efficacy and safety comparable with those of current therapies and should hold a place as a new minimally invasive option for patients with gastric outlet obstruction. Clinical trial identification number: NCT01522573 PMID:27004243

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

    PubMed

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

    2011-11-01

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

  9. Clinical outcomes of endoscopic ultrasound-guided ethanol injection for hepatocellular carcinoma in the caudate lobe

    PubMed Central

    Nakaji, So; Hirata, Nobuto; Mikata, Rintaro; Kobayashi, Masayoshi; Shiratori, Toshiyasu; Ogasawara, Sadahisa; Ooka, Yoshihiko; Tsuyuguchi, Toshio; Yamaguchi, Taketo; Yokosuka, Osamu

    2016-01-01

    Background and study aims: Accurately puncturing hepatocellular carcinomas (HCC) that arise from the caudate lobe is generally considered to be technically difficult. We conducted a retrospective study to evaluate the feasibility and safety (the therapeutic outcomes and adverse events) of endoscopic ultrasound (EUS)-guided ethanol injection as a novel treatment for HCC in the caudate lobe. Patients and methods: Twelve patients with early-stage HCC of the caudate lobe that were treated with EUS-guided ethanol injection at two tertiary referral centers were reviewed retrospectively. To evaluate the therapeutic effect of the treatment, a local control curve and an overall survival curve were constructed using the Kaplan–Meier method. Results: The mean follow-up duration was 31.0 months. The 1-year local control rate was 80.2 %, and recurrent lesions developed in 2 cases (after 3 and 9 months, respectively). The overall survival rate was 91.7 %, 75.0 %, and 53.3 % at 1, 2, and 3 years, respectively. Concerning procedure-related adverse events (AEs), 2 patients suffered episodes of fever lasting a few days; however, no serious AEs occurred. Conclusions: EUS-guided ethanol injection could be a useful treatment for early-stage HCC in the caudate lobe because of its simplicity and reduced invasiveness. PMID:27747288

  10. Endoscopic ultrasound characteristics of pancreatic lymphoepithelial cysts: A case series from a large referral center

    PubMed Central

    Dalal, Kunal S.; DeWitt, John M.; Sherman, Stuart; Cramer, Harvey M.; Tirkes, Temel; Al-Haddad, Mohammad A.

    2016-01-01

    Background and Objectives: Lymphoepithelial cysts (LECs) of the pancreas are benign lesions that can mimic cystic neoplasms on imaging. Endoscopic ultrasound (EUS) features have not been well described. We aimed to describe the clinical and EUS characteristics of LECs and the present outcomes of management at a high-volume referral center. Materials and Methods: We identified patients who underwent EUS and were found to have LECs based on fine-needle aspiration (FNA) cytology or surgical pathology from existing databases. EUS features, imaging characteristics, and pathology results were described. Results: Sixteen patients were found to have 17 LECs. The mean size was 33 mm ± 15 mm. Locations within the pancreas included 10 lesions in the tail, 3 in the body, 1 in the uncinate process; the remaining 3 were exophytic. Six lesions were anechoic, 6 were hypoechoic, and 5 had mixed echogenicity. Nine lesions had mixed solid/cystic components, 7 were purely cystic, and 1 was solid. Cyst fluid was thick or viscous in six cases and thin in three. Eleven patients had diagnostic cytopathology. Six patients ultimately underwent surgery due to symptoms, nondiagnostic FNA, or other clinical concerns for malignancy. Conclusions: Pancreatic LECs have variable morphology and echogenicity on EUS, but the appearance of a cyst with variable solid and cystic components combined with the appearance of thick, turbid, and viscous aspirate should raise suspicion for an LEC. The majority of patients with LECs at our center avoided surgery for LECs on the basis of diagnostic EUS-FNA. PMID:27503157

  11. Endoscopic ultrasound guided fine needle aspiration of non‐pancreatic lesions: an institutional experience

    PubMed Central

    Anand, Dipti; Barroeta, Julieta E; Gupta, Prabodh K; Kochman, Michael; Baloch, Zubair W

    2007-01-01

    Background Endoscopic ultrasound guided fine needle aspiration biopsy (EUS‐FNA) has proven to be an effective diagnostic modality for the detection and staging of pancreatic malignancies. In recent years EUS‐FNA has also been used to diagnose lesions of non‐pancreatic sites such as structures in close proximity to the gut wall within the mediastinum, abdomen, pelvis and retro‐peritoneum. Aims To evaluate experience with EUS‐FNA of non‐pancreatic sites at a large university medical centre. Methods The study cohort included 234 patients who underwent EUS‐FNA of 246 lesions in non‐pancreatic sites (122 peri‐pancreatic and coeliac lymph nodes; 9 peri‐pancreatic masses; other sites: mediastinum 12, gastric 25, liver 27, oesophagus 17, duodenum/colon/rectum 15, retro‐peritoneum 8, lung 7, miscellaneous 4). Results The cytology diagnoses were classified as non‐neoplastic/reactive in 82 (33%), atypical/suspicious for malignancy in 25 (10%), malignant in 86 (35%) and non‐diagnostic in 53 (22%) cases. Surgical pathology follow‐up was available in 75 (31%) cases. Excluding the non‐diagnostic cases there were 7 false negative and 3 false positive cases. The sensitivity, specificity and positive predictive value of EUS‐FNA in the diagnosis of lesions of non‐pancreatic sites was 92%, 98% and 97%, respectively. Conclusions EUS‐FNA can be effectively used as a diagnostic modality in the diagnosis of lesions from non‐pancreatic sites. PMID:17220205

  12. Performance and Clinical Role of Endoscopic Ultrasound Fine Needle Aspiration for Diagnosing Gastrointestinal Intramural Lesions

    PubMed Central

    Sung, Hea Jung; Park, Eun Young; Moon, Sung Jin; Lim, Chul Hyun; Kim, Jin Su; Park, Jae Myung; Lee, In Seok; Kim, Sang Woo; Choi, Myung-Gyu; Choi, Kyu Yong

    2013-01-01

    Background/Aims We evaluated the performance, clinical role, and diagnostic accuracy of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) in gastrointestinal intramural lesions. Methods Procedural and pathologic data were reviewed from consecutive patients undergoing EUS-FNA for intramural lesions. Final diagnoses were determined by surgical histopathologic conformation and the diagnosis of malignancy, including clinical follow-up with repeat imaging. Results Forty-six patients (mean age, 47 years; 24 males) underwent EUS-FNA. Lesions were located in the stomach (n=31), esophagus (n=5), and duodenum (n=10). The median lesion size was 2 cm (range, 1 to 20.6). Final diagnoses were obtained in 22 patients (48%). EUS-FNA was diagnostic in 40 patients (87%). The diagnostic accuracy of cytology for differentiating between benign and malignant lesions was 82%; diagnostic error occurred in three patients (6%). The cytologic results influenced clinical judgment in 78% cases. The primary reasons for negative or no clinical impact were false-negative results, misdirected patient management, and inconclusive cytology. Conclusions EUS-FNA exhibited an 87% diagnostic yield for gastrointestinal intramural lesions; the accuracy of cytology for differentiating malignancy was 82%. The limitations of EUS-FNA were primarily because of nondiagnostic sampling (9%) and probable diagnostic error (6%); these factors may influence the clinical role of EUS-FNA. PMID:24340255

  13. Role of contrast-enhanced harmonic endoscopic ultrasound in submucosal tumors

    PubMed Central

    Alvarez-Sanchez, Maria Victoria; Gincul, Rodica; Lefort, Christine; Napoleon, Bertrand

    2016-01-01

    With the widespread use of endoscopy, gastrointestinal submucosal lesions are now more commonly discovered. Although endoscopic ultrasound (EUS) is superior to all other imaging techniques for the diagnosis of submucosal tumors (SMTs), it is still suboptimal for differentiating hypoechoic lesions arising from the fourth sonographic gastrointestinal wall layer, which encompass tumors with very different prognosis. EUS tissue acquisition has provided with the unique opportunity to obtain histological confirmation, but it is not accurate enough to evaluate the malignant potential of gastrointestinal stromal tumors (GISTs). In the last years, contrast-enhanced harmonic EUS (CH-EUS) emerged as a powerful imaging modality to assess the microperfusion patterns of pancreatic tumors. Based on the distinct microvascularity of malignant SMTs, it was hypothesized that CH-EUS might also assist in the differential diagnosis of SMTs. Preliminary experience in this field is now available and suggests CH-EUS as a performant modality to distinguish between benign SMTs and GISTs and to evaluate the malignant potential of GISTs. High expectations are also relied on CH-EUS for the monitoring of antiangiogenic treatments of GISTs and the evaluation of gastrointestinal neuroendocrine tumors (NETs). PMID:28000626

  14. Role of contrast-enhanced harmonic endoscopic ultrasound in submucosal tumors.

    PubMed

    Alvarez-Sanchez, Maria Victoria; Gincul, Rodica; Lefort, Christine; Napoleon, Bertrand

    2016-01-01

    With the widespread use of endoscopy, gastrointestinal submucosal lesions are now more commonly discovered. Although endoscopic ultrasound (EUS) is superior to all other imaging techniques for the diagnosis of submucosal tumors (SMTs), it is still suboptimal for differentiating hypoechoic lesions arising from the fourth sonographic gastrointestinal wall layer, which encompass tumors with very different prognosis. EUS tissue acquisition has provided with the unique opportunity to obtain histological confirmation, but it is not accurate enough to evaluate the malignant potential of gastrointestinal stromal tumors (GISTs). In the last years, contrast-enhanced harmonic EUS (CH-EUS) emerged as a powerful imaging modality to assess the microperfusion patterns of pancreatic tumors. Based on the distinct microvascularity of malignant SMTs, it was hypothesized that CH-EUS might also assist in the differential diagnosis of SMTs. Preliminary experience in this field is now available and suggests CH-EUS as a performant modality to distinguish between benign SMTs and GISTs and to evaluate the malignant potential of GISTs. High expectations are also relied on CH-EUS for the monitoring of antiangiogenic treatments of GISTs and the evaluation of gastrointestinal neuroendocrine tumors (NETs).

  15. Bench-top testing of suction forces generated through endoscopic ultrasound-guided aspiration needles.

    PubMed

    Katanuma, Akio; Itoi, Takao; Baron, Todd H; Yasuda, Ichiro; Kin, Toshifumi; Yane, Kei; Maguchi, Hiroyuki; Yamazaki, Hajime; Sano, Itsuki; Minami, Ryuki; Manabu, Sen-yo; Ikarashi, Satoshi; Osanai, Manabu; Takahashi, Kuniyuki

    2015-05-01

    Adequate needle size and tissue acquisition techniques for endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) need further elucidation. Moreover, the actual negative pressure and suction forces of FNA needles remain unknown. We evaluated the suction forces of 19-gauge, 22-gauge, and 25-gauge conventional FNA needles and side hole aspiration needles using conventional negative pressure and the slow pull technique. Using a manometer, we determined the mean (SD) negative pressure and suction force for needle gauge, aspiration volume, and aspiration technique. We also evaluated the time to reach the maximum negative pressure. Suction force was comparatively higher in the 19-gauge needle when 50 ml of negative pressure was applied. Suction force using the slow pull method was very weak at 5% of pressure found with conventional methods. With the use of a 20-ml syringe, the time to reach the maximum negative pressure was 4 s in the 19-gauge needle, 11 s in the 22-gauge needle, and 80 s in the 25-gauge needle. Bench-top testing showed that suction force increases with a larger gauge needle and larger aspiration volume. The slow pull method produces a very weak suction force. The time to reach the maximum negative pressure was longest in the 25-gauge needle. © 2015 Japanese Society of Hepato-Biliary-Pancreatic Surgery.

  16. Role of endoscopic ultrasound in the molecular diagnosis of pancreatic cancer

    PubMed Central

    Bournet, Barbara; Gayral, Marion; Torrisani, Jérôme; Selves, Janick; Cordelier, Pierre; Buscail, Louis

    2014-01-01

    Pancreatic ductal adenocarcinoma remains one of the most deadly types of tumor. Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is a safe, cost-effective, and accurate technique for evaluating and staging pancreatic tumors. However, EUS-FNA may be inconclusive or doubtful in up to 20% of cases. This review underlines the clinical interest of the molecular analysis of samples obtained by EUS-FNA in assessing diagnosis or prognosis of pancreatic cancer, especially in locally advanced tumors. On EUS-FNA materials DNA, mRNA and miRNA can be extracted, amplified, quantified and subjected to methylation assay. Kras mutation assay, improves diagnosis of pancreatic cancer. When facing to clinical and radiological presentations of pseudo-tumorous chronic pancreatitis, wild-type Kras is evocative of benignity. Conversely, in front of a pancreatic mass suspected of malignancy, a mutated Kras is highly evocative of pancreatic adenocarcinoma. This strategy can reduce false-negative diagnoses, avoids the delay of making decisions and reduces loss of surgical resectability. Similar approaches are conducted using analysis of miRNA expression as well as Mucin or markers of invasion (S100P, S100A6, PLAT or PLAU). Beyond the diagnosis approach, the prediction of response to treatment can be also investigated form biomarkers expression within EUS-FNA materials. PMID:25152579

  17. Endoscopic Ultrasound-Guided Fine-Needle Aspiration of the Adrenal Glands: Analysis of 21 Patients

    PubMed Central

    Puri, Rajesh; Choudhary, Narendra S.; Kotecha, Hardik; Misra, Smruti Ranjan; Bhagat, Suraj; Paliwal, Manish; Madan, Kaushal; Saraf, Neeraj; Sarin, Haimanti; Guleria, Mridula; Sud, Randhir

    2015-01-01

    Background/Aims Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) cytology of adrenal masses helps in etiological diagnosis. The aim of this study was to evaluate the diagnostic yield of EUS-FNA of adrenal masses in cases where other imaging methods failed and/or were not feasible. Methods Twenty-one consecutive patients with adrenal masses, in whom adrenal FNA was performed because conventional imaging modalities failed and/or were not feasible, were prospectively evaluated over a period of 3 years. Results Of the 21 patients (mean age, 56±12.2 years; male:female ratio, 2:1), 12 had pyrexia of unknown origin and the other nine underwent evaluation for metastasis. The median lesion size was 2.4×1.6 cm. Ten patients were diagnosed with tuberculosis (shown by the presence of caseating granulomas [n=10] and acid-fast bacilli [n=4]). Two patients had EUS-FNA results suggestive of histoplasmosis. The other patients had metastatic lung carcinoma (n=6), hepatocellular carcinoma (n=1), and adrenal lipoma (n=1) and adrenal myelolipoma (n=1). EUS results were not suggestive of any particular etiology. No procedure-related adverse events occurred. Conclusions EUS-FNA is a safe and effective method for evaluating adrenal masses, and it yields diagnosis in cases where tissue diagnosis is impossible or has failed using conventional imaging modalities. PMID:25844346

  18. Endoscopic ultrasound-guided drainage of an amoebic liver abscess extending into the hepatic subcapsular space.

    PubMed

    Koizumi, Kazuya; Masuda, Sakue; Uojima, Haruki; Ichita, Chikamasa; Tokoro, Shinnosuke; Sasaki, Akiko; Egashira, Hideto; Kimbara, Takeshi; Kako, Makoto

    2015-08-01

    Here, we report a case of an amoebic liver abscess (ALA) successfully treated with endoscopic ultrasound (EUS)-guided liver abscess drainage (EUS-LAD). A 37-year-old male with a liver abscess was referred to our hospital due to disease progression despite receiving antibiotic therapy. Computed tomography showed an intrahepatic abscess extending into the hepatic subcapsular space. The abscess could not be punctured through the hepatic parenchyma percutaneously due to the presence of hepatic subcapsular lesions. Hence, EUS-LAD was performed via the transhepatic approach through the stomach. A 5-Fr pigtail-type nasocystic tube was inserted into the abscess through the hepatic parenchyma, with no procedure-related complications. The contents of the abscess had the appearance of anchovy paste which made us suspect an amoebic abscess; therefore, we started antibiotic therapy with metronidazole. Afterwards, serum anti-amoebic antibodies were found to be positive and the diagnosis of ALA was confirmed. Two weeks later, the size of the abscess decreased, and the patient's clinical symptoms disappeared. Hence, the tube was removed. There were no signs of recurrence during the follow-up period. The use of EUS-LAD for pyogenic or tuberculous abscesses has been reported previously. EUS-LAD for an ALA, similar to that for other liver abscesses, is an effective alternative to percutaneous transhepatic abscess drainage or surgical treatment.

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

    PubMed Central

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

    2014-01-01

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

  20. Role of endoscopic ultrasound in evaluation of unexplained common bile duct dilatation on magnetic resonance cholangiopancreatography.

    PubMed

    Rana, Surinder Singh; Bhasin, Deepak Kumar; Sharma, Vishal; Rao, Chalapathi; Gupta, Rajesh; Singh, Kartar

    2013-01-01

    Dilated common bile duct (CBD) without obvious cause is a not uncommon finding on magnetic resonance cholangiopancreatography (MRCP). The aim of this study was to evaluate the diagnostic performance of endoscopic ultrasound (EUS) in patients with unexplained dilated CBD on MRCP. Patients referred for EUS evaluation of a dilated CBD were retrospectively analyzed with respect to serum alkaline phosphatase prior to EUS and subsequent outcome after EUS. Over a 3-year period, 40 patients (24 males; mean age 38.9±9.9 years) with dilated CBD were retrospectively identified. Ten patients had elevated serum alkaline phosphatase. The diagnosis reached after EUS examination was: CBD stones in 15 (37.5%) with largest size of CBD stone being 9 mm, mass in CBD in 2 (5%), benign biliary stricture in 2 (5%), biliary stricture with underlying chronic pancreatitis in 1 (2.5%) patient respectively. EUS examination revealed normal CBD in 20 (50%) patients and two of these patients had periampullary diverticulum. All the patients with abnormal liver function tests had a detectable CBD pathology whereas 20/30 (66.6%) patients with normal liver biochemistry had normal EUS findings. There was no significant difference in the mean CBD diameter between the groups with demonstrable pathology compared with those without (P=0.64). EUS is a useful investigational modality for patients with unexplained dilated CBD on MRCP. The mean CBD diameter and the presence of normal liver function tests are not predictive of underlying pathology.

  1. Role of endoscopic ultrasound in evaluation of unexplained common bile duct dilatation on magnetic resonance cholangiopancreatography

    PubMed Central

    Rana, Surinder Singh; Bhasin, Deepak Kumar; Sharma, Vishal; Rao, Chalapathi; Gupta, Rajesh; Singh, Kartar

    2013-01-01

    Background Dilated common bile duct (CBD) without obvious cause is a not uncommon finding on magnetic resonance cholangiopancreatography (MRCP). The aim of this study was to evaluate the diagnostic performance of endoscopic ultrasound (EUS) in patients with unexplained dilated CBD on MRCP. Methods Patients referred for EUS evaluation of a dilated CBD were retrospectively analyzed with respect to serum alkaline phosphatase prior to EUS and subsequent outcome after EUS. Results Over a 3-year period, 40 patients (24 males; mean age 38.9±9.9 years) with dilated CBD were retrospectively identified. Ten patients had elevated serum alkaline phosphatase. The diagnosis reached after EUS examination was: CBD stones in 15 (37.5%) with largest size of CBD stone being 9 mm, mass in CBD in 2 (5%), benign biliary stricture in 2 (5%), biliary stricture with underlying chronic pancreatitis in 1 (2.5%) patient respectively. EUS examination revealed normal CBD in 20 (50%) patients and two of these patients had periampullary diverticulum. All the patients with abnormal liver function tests had a detectable CBD pathology whereas 20/30 (66.6%) patients with normal liver biochemistry had normal EUS findings. There was no significant difference in the mean CBD diameter between the groups with demonstrable pathology compared with those without (P=0.64). Conclusion EUS is a useful investigational modality for patients with unexplained dilated CBD on MRCP. The mean CBD diameter and the presence of normal liver function tests are not predictive of underlying pathology. PMID:24714761

  2. Promising outcomes of screening for pancreatic cancer by genetic testing and endoscopic ultrasound.

    PubMed

    Sud, Anchal; Wham, Deborah; Catalano, Marc; Guda, Nalini M

    2014-04-01

    This study aimed to determine if screening patients based on certain cancer syndromes or family history criteria can lead to early detection of pancreatic cancer. This was a cohort study from 2008 to 2011 at a large tertiary referral center. A total of 30 patients met high-risk criteria after genetic counseling and were referred to a gastroenterologist for possible endoscopic ultrasound (EUS). Of the 30 patients, 16 underwent EUS. Subsequently, 3 patients had fine needle aspiration. Two patients had pancreatic adenocarcinoma, and 1 patient had an intraductal papillary mucinous neoplasm with low-grade dysplasia. The 2 patients with pancreatic adenocarcinoma both had breast cancer and BRCA2 mutations. The patient with the intraductal papillary mucinous neoplasm had Peutz-Jeghers syndrome. All 3 patients underwent surgery and have remained cancer free. Genetic risk assessment with EUS +/- fine needle aspiration in high-risk patients may lead to earlier detection of pancreatic cancer and potentially improve overall morbidity and mortality. Greater emphasis should be placed on screening patients for hereditary cancer syndromes that increase the risk of pancreatic cancer.

  3. High Frame-Rate Imaging Applied to Quasi-static Elastography

    NASA Astrophysics Data System (ADS)

    Ramalli, Alessandro; Boni, Enrico; Basset, Olivier; Cachard, Christian; Tortoli, Piero

    Ultrasound elastography is an imaging technique addressed to investigate the tissue elastic properties. In freehand elastography, the ultrasound probe is moved by the operator to compress the tissue while the echo RF-data are processed to estimate the axial strain tensor by calculating the gradient of the corresponding displacement.

  4. Development of EndoTOFPET-US, a multi-modal endoscope for ultrasound and time of flight positron emission tomography

    NASA Astrophysics Data System (ADS)

    Pizzichemi, M.

    2014-02-01

    The EndoTOFPET-US project aims at delevoping a multi-modal imaging device that combines Ultrasound with Time-Of-Flight Positron Emission Tomography into an endoscopic imaging device. The goal is to obtain a coincidence time resolution of about 200 ps FWHM and sub-millimetric spatial resolution for the PET head, integrating the components in a very compact detector suitable for endoscopic use. The scanner will be exploited for the clinical test of new bio-markers especially targeted for prostate and pancreatic cancer as well as for diagnostic and surgical oncology. This paper focuses on the status of the Time-Of-Flight Positron Emission Tomograph under development for the EndoTOFPET-US project.

  5. Endoscopic ultrasound guided drainage of pancreatic fluid collections: Assessment of the procedure, technical details and review of the literature

    PubMed Central

    Puri, Rajesh; Thandassery, Ragesh Babu; Alfadda, Abdulrahman A; Kaabi, Saad Al

    2015-01-01

    Endoscopic ultrasound (EUS) guided drainage of pancreatic fluid collections (PFC) has become increasingly popular and become first line management option in many centers. Use of therapeutic echoendoscopes has greatly increased the applicability of EUS guided transmural drainage. Drainage is indicated in symptomatic PFCs, PFC related infection, bleed, luminal obstruction, fistulization and biliary obstruction. EUS guided transmural drainage of PFCs is preferred in patients with non bulging lesions, portal hypertension, bleeding tendency and in those whom conventional drainage has failed. In the present decade significant progress has been made in minimally invasive endoscopic techniques. There are newer stent designs, access devices and techniques for more efficient drainage of PFCs. In this review, we discuss the EUS guided drainage of PFCs in acute pancreatitis. PMID:25901214

  6. Endoscopic ultrasound guided drainage of pancreatic fluid collections: Assessment of the procedure, technical details and review of the literature.

    PubMed

    Puri, Rajesh; Thandassery, Ragesh Babu; Alfadda, Abdulrahman A; Kaabi, Saad Al

    2015-04-16

    Endoscopic ultrasound (EUS) guided drainage of pancreatic fluid collections (PFC) has become increasingly popular and become first line management option in many centers. Use of therapeutic echoendoscopes has greatly increased the applicability of EUS guided transmural drainage. Drainage is indicated in symptomatic PFCs, PFC related infection, bleed, luminal obstruction, fistulization and biliary obstruction. EUS guided transmural drainage of PFCs is preferred in patients with non bulging lesions, portal hypertension, bleeding tendency and in those whom conventional drainage has failed. In the present decade significant progress has been made in minimally invasive endoscopic techniques. There are newer stent designs, access devices and techniques for more efficient drainage of PFCs. In this review, we discuss the EUS guided drainage of PFCs in acute pancreatitis.

  7. Effects of premedication with Pronase for endoscopic ultrasound of the stomach: A randomized controlled trial

    PubMed Central

    Wang, Guo-Xin; Liu, Xiang; Wang, Sheng; Ge, Nan; Guo, Jin-Tao; Sun, Si-Yu

    2016-01-01

    AIM To analyze the effects of premedication with Pronase for endoscopic ultrasound (EUS) examination of the stomach. METHODS This was a prospective, randomized and controlled clinical study. All patients were randomly assigned to either the Pronase group or placebo group. The pretreatment solution was a mixed solution of 20000 U of Pronase and 60 mL sodium bicarbonate solution in the Pronase group, while an equal amount of sodium bicarbonate solution was administered to the placebo group. All operators, image evaluators and experimental recorders in EUS did not participate in the preparation and allocation of pretreatment solution. Two blinded investigators assessed the obscurity scores for the EUS images according to the size of artifacts (including ultrasound images of the gastric cavity and the gastric wall). Differences in imaging quality, the duration of examination and the usage of physiological saline during the examination process between the Pronase group and the control group were compared. RESULTS No differences existed in patient demographics between the two groups. For the gastric cavity, the Pronase group had significantly lower mean obscurity scores than the placebo group (1.0476 ± 0.77 vs 1.6129 ± 0.96, respectively, P = 0.000). The mean obscurity scores for the gastric mucosal surface were significantly lower in the Pronase group than the placebo group (1.2063 ± 0.90 vs 1.7581 ± 0.84, respectively, P = 0.001). The average EUS procedure duration for the Pronase group was 11.60 ± 3.32 min, which was significantly shorter than that of the placebo group (13.13 ± 3.81 min, P = 0.007). Less saline was used in the Pronase group than the placebo group, and the difference was significant (417.94 ± 121.38 mL vs 467.42 ± 104.52 mL, respectively, P = 0.016). CONCLUSION The group that had Pronase premedication prior to the EUS examination had clearer images than the placebo group. With Pronase premedication, the examination time was shorter, and the

  8. Quality assessment and factor analysis of systematic reviews and meta-analyses of endoscopic ultrasound diagnosis.

    PubMed

    Liu, Danlu; Jin, Jiaxin; Tian, Jinhui; Yang, Kehu

    2015-01-01

    Comprehensive monitoring of the quality of systematic reviews (SRs) and meta-analyses (MAs) of endoscopic ultrasound (EUS) requires complete and accurate reporting and methodology. To assess the reporting and methodological quality of SRs/MAs on EUS diagnosis and to explore the potential factors influencing articles' quality. The quality of the reporting and methodology was evaluated in relation to the adherence of papers to the PRISMA checklist and the AMSTAR quality scale. The total scores for every criterion and for every article on the two standards were calculated. Data were evaluated and analyzed using SPSS17.0 and RevMan 5.1 in terms of publication time, category of reviews, category of journals, and funding resource. A total of 72 SRs/MAs was included, but no Cochrane Systematic Reviews (CSRs) were obtained. The number of SRs/MAs ranged from 1 in 1998 to 15 in 2013; 88.1% used the QUADAS tool; the average overall scores by PRISMA statement and AMSTAR tool were 19.9 and 5.4, respectively. Scores on some items showed substantial improvement after publication of PRISMA and AMSTAR. However, no reviews followed the criterion of protocol and registration, and only 11.1% of articles fulfilled the criterion of literature search. SRs/MAs from the Science Citation Index (SCI) were of better quality than non-SCI studies. Funding resource made no difference to quality. Regression analysis showed that time of publication and inclusion in the SCI were significantly correlated with total scores on the two standards. The reporting and methodological quality of SRs/MAs on EUS diagnosis has improved measurably since PRISMA and AMSTAR checklists released. It is hoped that CSR in this field will be produced. Literature searching and protocol criteria, as well as QUADAS-2 tool need to be addressed more in the future. Time of publication and SCI relate more to the overall quality of SRs/MAs than does funding resource.

  9. Contrast-enhanced endoscopic ultrasound in discrimination between benign and malignant mediastinal and abdominal lymph nodes.

    PubMed

    Hocke, Michael; Menges, Markus; Topalidis, Theodor; Dietrich, Christoph F; Stallmach, Andreas

    2008-04-01

    Enlarged lymph nodes in the mediastinum reflect neoplastic, infectious or other diseases. The classification of these nodes is crucial in the management of the patient. Currently, only invasive measures obtaining tissue samples reach satisfying specificity. Contrast-enhanced endoscopic ultrasound (EUS) may offer a non-invasive alternative. A total of 122 patients (age: 63 +/- 15 years, 92 males, 30 females) with enlarged mediastinal and/or paraaortic lymph nodes diagnosed by CT scan were included in the study. EUS-guided fine needle aspiration was performed and cytologic specimens were diagnosed as representing a malignant or benign process in case of Papanicolau IV and V, or Papanicolau I and II, respectively. Based on cytology results, the investigated lymph nodes were classified as neoplastic (n = 48) or non-neoplastic lymph nodes. Using the B-mode criteria the preliminary diagnosis was confirmed in 64 out of 74 benign lymph nodes (specificity 86%). Regarding malignant lymph nodes 33 of 48 were confirmed (sensitivity 68%). Using the advanced contrast-enhanced EUS criteria the diagnosis was confirmed in 68 of 74 benign lymph nodes (specificity 91%). However, in case of malignant lymph nodes the number of correct diagnoses dropped to 29 of 48 lymph nodes (sensitivity 60%). The contrast-enhanced EUS criteria to identify benign lymph nodes and node enlargement in malignant lymphoma do not differ. If those ten patients with malignant lymphoma are excluded, the sensitivity of the contrast enhanced EUS for malignant lymph nodes rises to 73%. Contrast-enhanced EUS improves the specificity in diagnosing benign lymph nodes as compared to B-mode EUS. It does not improve the correct identification of malignant lymph nodes and cannot replace EUS-guided fine-needle aspiration.

  10. Performance of novel tissue harmonic echo imaging using endoscopic ultrasound for pancreatic diseases.

    PubMed

    Matsumoto, Kazuyuki; Katanuma, Akio; Maguchi, Hiroyuki; Takahashi, Kuniyuki; Osanai, Manabu; Yane, Kei; Kin, Toshifumi; Takaki, Ryo; Matsumori, Tomoaki; Gon, Katsushige; Tomonari, Akiko; Nojima, Masanori

    2016-01-01

    Recently, tissue harmonic echo (THE) imaging has advanced with the development of a new endoscopic ultrasound (EUS) monitor/processing unit. With this new technology, penetration (THE-P) and resolution (THE-R) images can be obtained. The aim of this study was to investigate the performance of this novel THE imaging using a new processing unit for pancreatic diseases. Fifty patients with pancreatic lesions (38 cystic, 12 solid) were retrospectively analyzed. At each examination, 3 EUS images of the same pancreatic lesion were obtained using B-mode, THE-P mode, and THE-R mode imaging. Each set of EUS images was randomly arranged and evaluated independently by 4 physicians blinded to the imaging technique. Images were compared using a Likert scale 5-point grading system for each parameter. For cystic lesions, THE-P mode images were significantly superior to conventional B-mode images for visualizing the boundary, septum, nodules, and total image quality (P < 0.05). THE-R mode images were significantly superior to conventional B-mode images for visualizing the boundary, septum, and total image quality (P < 0.05). However, for solid lesions, there was no significant difference in all the evaluation points between THE-P and conventional B-mode images. THE-R mode images were inferior to conventional B-mode images for visualizing the boundary, internal structure, and total image quality (P < 0.05). For pancreatic cystic lesions, THE mode images provided better lesion characterization than conventional B-mode images. Further research is required to determine if this improvement will result in improved EUS diagnostics.

  11. When trainees reach competency in performing endoscopic ultrasound: a systematic review

    PubMed Central

    Shahidi, Neal; Ou, George; Lam, Eric; Enns, Robert; Telford, Jennifer

    2017-01-01

    Background/Study aim The American Society for Gastrointestinal Endoscopy (ASGE) recommends that trainees complete 150 endoscopic ultrasound (EUS) procedures before assessing competency. However, this recommendation is largely based on limited evidence and expert opinion. With new evidence suggesting that this historical threshold is underestimating training requirements, we evaluated the learning curve for achieving competency in EUS. Patients/Materials and methods Two investigators independently searched MEDLINE for full-text citations assessing the learning curve for achieving competency in EUS in the period 1946 to 25 March 2016. A learning curve was defined as either a tabulated or graphic representation of competency as a function of increasing EUS experience. Results Eight studies assessing 28 trainees and 7051 EUS procedures were included. When stratifying studies based on procedural indication: three studies assessed competency in evaluating mucosal lesions, three studies assessed competency in EUS fine-needle aspiration (EUS-FNA), and two studies assessed comprehensive competency. Among studies assessing mucosal lesion T-staging accuracy, competency was achieved by 65 to 231 procedures. Among studies assessing EUS-FNA, competency was achieved by 30 to 40 procedures. Among the two studies assessing comprehensive competency in EUS, competency was not achieved in either study across all trainees. Only four of 17 trainees reached competency by 225 to 295 EUS procedures. Conclusion As EUS competency assessment has evolved to more closely reflect independent clinical practice, the number of procedures required to achieve competency has risen well above ASGE recommendations. Advanced endoscopy training programs and specialty societies need to re-assess the structure of EUS training. PMID:28367496

  12. The cellularity yield of three different 22-gauge endoscopic ultrasound fine needle aspiration needles.

    PubMed

    Othman, Mohamed O; Abdelfatah, Mohamed M; Padilla, Osvaldo; Hussinat, Maha; Elhanafi, Sherif; Eloliby, Mohamed; Torabi, Alireza; Hakim, Nawar; Boman, Darius A

    2017-05-01

    Endoscopic ultrasound (EUS) fine needle aspiration (FNA) is an integral part in the diagnosis of pancreatic, intestinal and extra-intestinal masses or lesions. There is no clear data on the superiority of the core biopsy needle over standard 22-gauge needles. The aim of this study is to prospectively compare the cellularity yield of three commonly used 22-gauge FNA needles available in the US market. This is a prospective, randomized study comparing the cellularity yield of three commercially available EUS needles (two standard FNA needles and core biopsy needle). Two blinded pathologists evaluated the cytology specimens based on an already agreed upon cytology score. We included adult patients (18-80 years old) who presented to our endoscopy unit for FNA of pancreatic or extrapancreatic masses. 109 patients (57 F, 52 M) were recruited to the study, 88 lesions were pancreatic lesions. 39 patients were recruited in the EZ Shot 2™ group, 36 in the Procore(®) group and 34 in the Expect™ group. The average cellularity score and the mean number of passes (SD) were not different between the three needles; P = 0.91 and P = 0.16, respectively. There was no difference between the three needles in obtaining an onsite diagnosis (P = 0.627) and no difference in reported adverse events between the three groups. The cellularity yields, the mean number of passes and reported adverse events were similar in the three compared 22-gauge needles. Diagn. Cytopathol. 2017;45:426-432. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  13. Performance of endoscopic ultrasound in staging rectal adenocarcinoma appropriate for primary surgical resection.

    PubMed

    Ahuja, Nitin K; Sauer, Bryan G; Wang, Andrew Y; White, Grace E; Zabolotsky, Andrew; Koons, Ann; Leung, Wesley; Sarkaria, Savreet; Kahaleh, Michel; Waxman, Irving; Siddiqui, Ali A; Shami, Vanessa M

    2015-02-01

    Endoscopic ultrasound (EUS) often is used to stage rectal cancer and thereby guide treatment. Prior assessments of its accuracy have been limited by small sets of data collected from tumors of varying stages. We aimed to characterize the diagnostic performance of EUS analysis of rectal cancer, paying particular attention to determining whether patients should undergo primary surgical resection. We performed a retrospective observational study using procedural databases and electronic medical records from 4 academic tertiary-care hospitals, collecting data on EUS analyses from 2000 through 2012. Data were analyzed from 86 patients with rectal cancer initially staged as T2N0 by EUS. The negative predictive value (NPV) was calculated by comparing initial stages determined by EUS with those determined by pathology analysis of surgical samples. Logistic regression models were used to assess variation in diagnostic performance with case attributes. EUS excluded advanced tumor depth with an NPV of 0.837 (95% confidence interval [CI], 0.742-0.908), nodal metastasis with an NPV of 0.872 (95% CI, 0.783-0.934), and both together with an NPV of 0.767 (95% CI, 0.664-0.852) compared with pathology analysis. Incorrect staging by EUS affected treatment decision making for 20 of 86 patients (23.3%). Patient age at time of the procedure correlated with the NPV for metastasis to lymph node, but no other patient features were associated significantly with diagnostic performance. Based on a multicenter retrospective study, EUS staging of rectal cancer as T2N0 excludes advanced tumor depth and nodal metastasis, respectively, with an approximate NPV of 85%, similar to that of other modalities. EUS has an error rate of approximately 23% in identifying disease appropriate for surgical resection, which is lower than previously reported. Copyright © 2015 AGA Institute. Published by Elsevier Inc. All rights reserved.

  14. Contrast-harmonic endoscopic ultrasound for the diagnosis of pancreatic adenocarcinoma: a prospective multicenter trial.

    PubMed

    Gincul, Rodica; Palazzo, Maxime; Pujol, Bertrand; Tubach, Florence; Palazzo, Laurent; Lefort, Christine; Fumex, Fabien; Lombard, Alexandra; Ribeiro, Daniel; Fabre, Monique; Hervieu, Valerie; Labadie, Michel; Ponchon, Thierry; Napoléon, Bertrand

    2014-05-01

    Histology is the gold standard for the diagnosis of pancreatic adenocarcinoma. However, the negative predictive value of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) for the diagnosis remains low. The aims of this prospective multicenter study were: (1) to compare the performance of contrast-harmonic EUS (CH-EUS) with that of EUS-FNA for the diagnosis of pancreatic adenocarcinoma; (2) to assess the intra- and interobserver concordances of CH-EUS. A total of 100 consecutive patients with a solid pancreatic mass of unknown origin were prospectively included at three centers (July 2009 - April 2010). All patients were examined by CH-EUS followed by EUS-FNA. Absence of vascular enhancement at CH-EUS was regarded as a sign for pancreatic adenocarcinoma. The final diagnosis (gold standard) was based on pathological examination (EUS-FNA, surgery) or 12-month follow-up.  The final diagnoses were: 69 adenocarcinoma, 10 neuroendocrine tumors, 13 chronic pancreatitis, and 8 other lesions. In diagnosing adenocarcinoma, CH-EUS and EUS-FNA had respective accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of 95 %, 96 %, 94 %, 97 %, and 91 %, and of 95 %, 93 %, 100 %, 100 %, and 86 % without significant difference. Five false-negative cases with EUS-FNA were correctly classified by CH-EUS. Interobserver agreement (seven endosonographers) was good (kappa 0.66). Intraobserver agreement was good to excellent (kappa 0.76 for junior, 0.90 for senior). The performance of CH-EUS for the diagnosis of pancreatic adenocarcinoma was excellent. The good intra- and interobserver concordances suggest an excellent reproducibility. CH-EUS could help to guide the choice between surgery and follow-up when EUS-FNA is inconclusive. © Georg Thieme Verlag KG Stuttgart · New York.

  15. Endoscopic ultrasound-guided needle-based confocal laser endomicroscopy in solid pancreatic masses.

    PubMed

    Giovannini, Marc; Caillol, Fabrice; Monges, Geneviève; Poizat, Flora; Lemaistre, Anne-Isabelle; Pujol, Bertrand; Lucidarme, Damien; Palazzo, Laurent; Napoléon, Bertrand

    2016-10-01

    The differential diagnosis of solid pancreatic masses by endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is currently suboptimal in centers that are not equipped with rapid on-site evaluation. Needle-based confocal laser endomicroscopy (nCLE) enables real-time in vivo microscopic imaging during endoscopy. This study aimed to describe nCLE interpretation criteria for the characterization of pancreatic masses, with histopathological correlation, and to perform the first validation of these criteria. A total of 40 patients were evaluated by EUS-FNA combined with nCLE for the diagnosis of pancreatic masses. Final diagnosis was based on EUS-FNA histology and follow-up at 1 year. Five unblinded examiners defined nCLE criteria for adenocarcinoma, chronic pancreatitis, and neuroendocrine tumor (NET) using a set of video sequences from 14 patients with confirmed pathology (Step 1). These criteria were retrospectively validated by four independent, blinded examiners using sequences from 32 patients (Step 2). nCLE criteria were described for adenocarcinoma (dark cell aggregates, irregular vessels with leakages of fluorescein), chronic pancreatitis (residual regular glandular pancreatic structures), and NET (black cell aggregates surrounded by vessels and fibrotic areas). These criteria correlated with the histological features of the corresponding lesions. In the validation review, a conclusive nCLE result was obtained in 75 % of cases (96 % correct). Statistical evaluation provided promising results, with high specificity, and negative and positive predictive values for all types of pancreatic masses. Considering the low negative predictive value of EUS-FNA, nCLE could help to rule out malignancy after a previous inconclusive EUS-FNA. Larger studies are required to confirm these findings and to establish the role of nCLE in the diagnosis of pancreatic masses. ClinicalTrials.gov (NCT01563133). © Georg Thieme Verlag KG Stuttgart · New York.

  16. Accuracy of endoscopic ultrasound-guided fine-needle aspiration in the suspicion of pancreatic metastases

    PubMed Central

    2013-01-01

    Background Metastases to the pancreas are rare, and usually mistaken for primary pancreatic cancers. This study aimed to describe the histology results of solid pancreatic tumours obtained by endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) for diagnosis of metastases to the pancreas. Methods In a retrospective review, patients with pancreatic solid tumours and history of previous extrapancreatic cancer underwent EUS-FNA from January/1997 to December/2010. Most patients were followed-up until death and some of them were still alive at the end of the study. The performance of EUS-FNA for diagnosis of pancreatic metastases was analyzed. Symptoms, time frame between primary tumour diagnosis and the finding of metastases, and survival after diagnosis were also analyzed. Results 37 patients underwent EUS-FNA for probable pancreas metastases. Most cases (65%) presented with symptoms, especially upper abdominal pain (46%). Median time between detection of the first tumour and the finding of pancreatic metastases was 36 months. Metastases were confirmed in 32 (1.6%) cases, 30 of them by EUS-FNA, and 2 by surgery. Other 5 cases were non-metastatic. Most metastases were from lymphoma, colon, lung, and kidney. Twelve (32%) patients were submitted to surgery. Median survival after diagnosis of pancreatic metastases was 9 months, with no difference of survival between surgical and non-surgical cases. Sensitivity, specificity, positive and negative predictive values, and accuracy of EUS-FNA with histology analysis of the specimens for diagnosis of pancreatic metastases were, respectively, 93.8%, 60%, 93.8%, 60% and 89%. Conclusion EUS-FNA with histology of the specimens is a sensitive and accurate method for definitive diagnosis of metastatic disease in patients with a previous history of extrapancreatic malignancies. PMID:23578194

  17. The Use of Standard Gastrointestinal Endoscopic Ultrasound to Assess Cardiac Anatomy.

    PubMed

    Sentissi, Kinza; Sawhney, Mandeep S; Pleskow, Douglas; Sepe, Paul; Mella, Jose M; Kwittken, Benjamin; Ketwaroo, Gyanprakash; Subramaniam, Balachundhar

    2016-09-01

    In this prospective observational study, conducted at an academic medical center, we evaluated the feasibility of performing a basic transesophageal echocardiography (TEE) examination using endoscopic ultrasound (EUS) technology to determine what cardiac structures could be assessed. This may be potentially beneficial during hemodynamic emergencies in the endoscopy suite resulting from hypovolemia, depressed ventricular function, aortic dissection, pericardial effusions, or aortic stenosis. Of the 20 patients enrolled, 18 underwent EUS with a linear echoendoscope for standard clinical indications followed by a cardiac assessment performed under the guidance of a TEE-certified cardiac anesthesiologist. Eight of the 20 standard views of cardiovascular structures per the 1999 American Society of Echocardiography/Society of Cardiovascular Anesthesiologists guidelines for TEE could be obtained using the linear echoendoscope. The following cardiac valvular structures were visualized: aortic valve (100%), mitral valve (100%), tricuspid valve (33%), and pulmonic valve (11%). Left ventricular and right ventricular systolic function could be assessed in 89% and 67% of patients, respectively. Other structures such as the ascending and descending aorta, pericardium, left atrial appendage, and interatrial septum were identified in 100% of patients. Doppler-dependent functions could not be assessed. Given that the EUS images were not directly compared with TEE in these patients, we cannot comment definitively on the quality of these assessments and further studies would need to be performed to make a formal comparison. Based on this study, EUS technology can consistently assess the mitral valve, aortic valve, aorta, pericardium, and left ventricular function. Given its limitations, EUS technology, although not a substitute for formal echocardiography, could be a helpful early diagnostic tool in an emergency setting.

  18. Performance of novel tissue harmonic echo imaging using endoscopic ultrasound for pancreatic diseases

    PubMed Central

    Matsumoto, Kazuyuki; Katanuma, Akio; Maguchi, Hiroyuki; Takahashi, Kuniyuki; Osanai, Manabu; Yane, Kei; Kin, Toshifumi; Takaki, Ryo; Matsumori, Tomoaki; Gon, Katsushige; Tomonari, Akiko; Nojima, Masanori

    2016-01-01

    Background and study aims: Recently, tissue harmonic echo (THE) imaging has advanced with the development of a new endoscopic ultrasound (EUS) monitor/processing unit. With this new technology, penetration (THE-P) and resolution (THE-R) images can be obtained. The aim of this study was to investigate the performance of this novel THE imaging using a new processing unit for pancreatic diseases. Patients and methods: Fifty patients with pancreatic lesions (38 cystic, 12 solid) were retrospectively analyzed. At each examination, 3 EUS images of the same pancreatic lesion were obtained using B-mode, THE-P mode, and THE-R mode imaging. Each set of EUS images was randomly arranged and evaluated independently by 4 physicians blinded to the imaging technique. Images were compared using a Likert scale 5-point grading system for each parameter. Results: For cystic lesions, THE-P mode images were significantly superior to conventional B-mode images for visualizing the boundary, septum, nodules, and total image quality (P < 0.05). THE-R mode images were significantly superior to conventional B-mode images for visualizing the boundary, septum, and total image quality (P < 0.05). However, for solid lesions, there was no significant difference in all the evaluation points between THE-P and conventional B-mode images. THE-R mode images were inferior to conventional B-mode images for visualizing the boundary, internal structure, and total image quality (P < 0.05). Conclusions: For pancreatic cystic lesions, THE mode images provided better lesion characterization than conventional B-mode images. Further research is required to determine if this improvement will result in improved EUS diagnostics. PMID:26793784

  19. Prognostic significance of the endoscopic ultrasound defined lymph node metastasis count in esophageal cancer.

    PubMed

    Twine, C P; Roberts, S A; Rawlinson, C E; Davies, L; Escofet, X; Dave, B V; Crosby, T D; Lewis, W G

    2010-11-01

    The key prognostic factor which predicts outcome after esophagectomy for cancer is the number of malignant lymph node metastases, but data regarding the accuracy of endoscopic ultrasound (EUS) in determining and predicting the metastatic lymph node count preoperatively are limited. The aim of this study was to assess the prognostic significance of EUS defined lymph node metastasis count (eLNMC) in patients diagnosed with esophageal cancer. Two hundred and sixty-seven consecutive patients (median age 63 years, 187 months) underwent specialist EUS followed by stage directed multidisciplinary treatment (183 esophagectomy [64 neoadjuvant chemotherapy, 19 neoadjuvant chemoradiotherapy], 79 definitive chemoradiotherapy, and 5 palliative therapy). The eLNMC was subdivided into four groups (0, 1, 2 to 4, >4) and the primary measure of outcome was survival. Survival was related to EUS tumor (T) stage (P < 0.0001), EUS node (N) stage (P < 0.0001), EUS tumor length (p < 0.0001), and eLNMC (P < 0.0001). Multivariable analysis revealed EUS tumor length (hazard ratio [HR] 1.071, 95% CI 1.008-1.138, P= 0.027) and eLNMC (HR 1.302, 95% CI 1.133-1.496, P= 0.0001) to be significantly and independently associated with survival. Median and 2-year survival for patients with 0, 1, 2-4, and >4 lymph node metastases were: 44 months and 71%, 36 months and 59%, 24 months and 50%, and 17 months and 32%, respectively. The total number of EUS defined lymph node metastases was an important and significant prognostic indicator. © 2010 Copyright the Authors. Journal compilation © 2010, Wiley Periodicals, Inc. and the International Society for Diseases of the Esophagus.

  20. When trainees reach competency in performing endoscopic ultrasound: a systematic review.

    PubMed

    Shahidi, Neal; Ou, George; Lam, Eric; Enns, Robert; Telford, Jennifer

    2017-04-01

    Background/Study aim The American Society for Gastrointestinal Endoscopy (ASGE) recommends that trainees complete 150 endoscopic ultrasound (EUS) procedures before assessing competency. However, this recommendation is largely based on limited evidence and expert opinion. With new evidence suggesting that this historical threshold is underestimating training requirements, we evaluated the learning curve for achieving competency in EUS. Patients/Materials and methods Two investigators independently searched MEDLINE for full-text citations assessing the learning curve for achieving competency in EUS in the period 1946 to 25 March 2016. A learning curve was defined as either a tabulated or graphic representation of competency as a function of increasing EUS experience. Results Eight studies assessing 28 trainees and 7051 EUS procedures were included. When stratifying studies based on procedural indication: three studies assessed competency in evaluating mucosal lesions, three studies assessed competency in EUS fine-needle aspiration (EUS-FNA), and two studies assessed comprehensive competency. Among studies assessing mucosal lesion T-staging accuracy, competency was achieved by 65 to 231 procedures. Among studies assessing EUS-FNA, competency was achieved by 30 to 40 procedures. Among the two studies assessing comprehensive competency in EUS, competency was not achieved in either study across all trainees. Only four of 17 trainees reached competency by 225 to 295 EUS procedures. Conclusion As EUS competency assessment has evolved to more closely reflect independent clinical practice, the number of procedures required to achieve competency has risen well above ASGE recommendations. Advanced endoscopy training programs and specialty societies need to re-assess the structure of EUS training.

  1. Optimal biliary access point and learning curve for endoscopic ultrasound-guided hepaticogastrostomy with transmural stenting

    PubMed Central

    Oh, Dongwook; Park, Do Hyun; Song, Tae Jun; Lee, Sang Soo; Seo, Dong-Wan; Lee, Sung Koo; Kim, Myung-Hwan

    2016-01-01

    Background: Although endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS) with transmural stenting has increased for biliary decompression in patients with an inaccessible papilla, the optimal biliary access point and the learning curve of EUS-HGS have not been studied. We evaluated the optimal biliary access point and learning curve for technically successful EUS-HGS. Methods: 129 consecutive patients (male n = 81, 62.3%; malignant n = 113, 87.6%) who underwent EUS-HGS due to an inaccessible papilla were enrolled. EUS finding and procedure times according to each needle puncture attempt in EUS-HGS were prospectively measured. Learning curves of EUS-HGS were calculated for two main outcome measurements (procedure time and adverse events) by using the moving average method and cumulative sum (CUSUM) analysis, respectively. Results: A total of 174 EUS-HGS attempts were performed in 129 patients. The mean number of needle punctures was 1.35 ± 0.57. Using the logistic regression model, bile duct diameter of the puncture site ⩽ 5 mm [odds ratio (OR) 3.7, 95% confidence interval (CI): 1.71–8.1, p < 0.01] and hepatic portion length [linear distance from the mural wall to the punctured bile duct wall on EUS; mean hepatic portion length was 27 mm (range 10–47 mm)] > 3 cm (OR 5.7, 95% CI: 2.7–12, p < 0.01) were associated with low technical success. Procedure time and adverse events were shorter after 24 cases, and stabilized at 33 cases of EUS-HGS, respectively. Conclusions: Our data suggest that a bile duct diameter > 5 mm and hepatic portion length 1 cm to ⩽ 3 cm on EUS may be suitable for successful EUS-HGS. In our learning curve analysis, over 33 cases might be required to achieve the plateau phase for successful EUS-HGS. PMID:28286558

  2. Successful Xenograft of Endoscopic Ultrasound-Guided Fine-Needle Aspiration Specimen from Human Extrahepatic Cholangiocarcinoma into an Immunodeficient Mouse

    PubMed Central

    Jang, Se Young; Bae, Han Ik; Lee, In Kyu; Park, Hwan Ki; Cho, Chang-Min

    2015-01-01

    Patient-derived tumor xenograft is the transfer of primary human tumors directly into an immunodeficient mouse. Patient-derived tumor xenograft plays an important role in the development and evaluation of new chemotherapeutic agents. We succeeded in generating a patient-derived tumor xenograft of a biliary tumor obtained by endoscopic ultrasound-guided fine-needle aspiration from a patient who had an inoperable extrahepatic cholangiocarcinoma. This patient-derived tumor xenograft will be a promising tool for individualized cancer therapy and can be used in developing new chemotherapeutic agents for the treatment of biliary cancer in the future. PMID:26087785

  3. Is Endoscopic Ultrasound (EUS) necessary in the pre-therapeutic assessment of Barrett’s esophagus with early neoplasia?

    PubMed Central

    Fernández-Sordo, Jacobo Ortiz; Konda, Vani J.A.; Chennat, Jennifer; Madrigal-Hoyos, Erika; Posner, Mitchell C.; Ferguson, Mark K.

    2012-01-01

    Endoscopic ultrasound (EUS) is considered the most accurate tool for the TNM staging of esophageal cancer, but its role in early Barrett’s neoplasia is still debatable. The aim was to evaluate the utility of EUS in Barrett’s patients prior to therapy. Retrospective review of 109 patients enrolled in a treatment protocol for Barrett’s neoplasia in our institution. EUS assessment was classified as suspicious for invasion in 19 patients; 84% of them had no evidence of invasion in final pathology. The assessment of depth of invasion of Barrett’s neoplasia based solely on EUS findings leads to overstaging in most patients. PMID:23205307

  4. Endoscopic Ultrasound-Guided Drainage of Intra-Abdominal Abscess after Gastric Perforation in a Patient Receiving Ramucirumab and Paclitaxel for Advanced Gastric Cancer

    PubMed Central

    Mandai, Koichiro; Shirakawa, Atsushi; Uno, Koji; Yasuda, Kenjiro

    2017-01-01

    Gastrointestinal perforation is a serious adverse event that occurs in approximately 1% of patients receiving ramucirumab and paclitaxel. A 67-year-old man with unresectable advanced gastric cancer was admitted to our hospital and treated with ramucirumab and paclitaxel. Gastric perforation occurred during the second cycle of chemotherapy. Although the patient's condition improved without surgery, an abscess developed in the intra-abdominal fluid collection resulting from the perforation. We performed endoscopic ultrasound-guided abscess drainage. The patient improved and was discharged in satisfactory condition. Endoscopic ultrasound-guided drainage is a treatment option for patients with intra-abdominal abscess following gastric perforation due to ramucirumab. PMID:28203161

  5. Endoscopic Ultrasound-Guided Drainage of Intra-Abdominal Abscess after Gastric Perforation in a Patient Receiving Ramucirumab and Paclitaxel for Advanced Gastric Cancer.

    PubMed

    Mandai, Koichiro; Shirakawa, Atsushi; Uno, Koji; Yasuda, Kenjiro

    2017-01-01

    Gastrointestinal perforation is a serious adverse event that occurs in approximately 1% of patients receiving ramucirumab and paclitaxel. A 67-year-old man with unresectable advanced gastric cancer was admitted to our hospital and treated with ramucirumab and paclitaxel. Gastric perforation occurred during the second cycle of chemotherapy. Although the patient's condition improved without surgery, an abscess developed in the intra-abdominal fluid collection resulting from the perforation. We performed endoscopic ultrasound-guided abscess drainage. The patient improved and was discharged in satisfactory condition. Endoscopic ultrasound-guided drainage is a treatment option for patients with intra-abdominal abscess following gastric perforation due to ramucirumab.

  6. A pilot study estimating liver fibrosis with ultrasound shear-wave elastography: does the cause of liver disease or location of measurement affect performance?

    PubMed

    Beland, Michael D; Brown, Sanford F; Machan, Jason T; Taliano, Ross J; Promrat, Kittichai; Cronan, John J

    2014-09-01

    The purpose of this study was to evaluate the diagnostic accuracy of real-time shear-wave elastography for assessment of liver fibrosis in an unselected patient population, comparing shear-wave elastography measurements obtained at and remote from the site of random liver biopsy. In a prospective study of 50 patients (21 with and 29 without hepatitis C) referred for clinically indicated random liver biopsy for diffuse liver disease, shear-wave elastography measurements were taken from four locations before biopsy: one at the left lobe, two at the right lobe, and one at the biopsy location. The mean, minimum, maximum, and SD of shear-wave elastography were compared with pathologic grading. Steatosis and serum markers were analyzed using multiple logistic regression. Optimized shear-wave elastography thresholds were calculated using AUC analysis. The AUC (95% CI) at the biopsy site, ipsilateral lobe, and contralateral lobe were 0.82 (0.63-1.0), 0.84 (0.67-1.0), and 0.59 (0.19-0.99) in hepatitis C patients; 0.89 (0.75-1.0), 0.88 (0.73-1.0), and 0.93 (0.80-1.0) in nonhepatitis C patients; and 0.85 (0.74-0.96), 0.89 (0.79-0.99), and 0.80 (0.67-0.93) in all patients, respectively. Optimized biopsy site shear-wave elastography values for detecting Metavir score F2 or greater were 1.87 m/s (75% sensitivity and specificity), 2.00 m/s (80% sensitivity and specificity), and 1.89 m/s (76% sensitivity and specificity) in hepatitis C, nonhepatitis C, and all patients, respectively. Steatosis and serum markers were not significant. Real-time shear-wave elastography accurately predicted significant fibrosis (stage ≥ 2) in an unselected patient population with diffuse disease, including patients with and without hepatitis C. Shear-wave elastography best predicts pathologic grading when taken at the biopsy site or ipsilateral lobe in hepatitis C patients. Percentage steatosis was not predictive of shear-wave elastography results.

  7. Posterior Shoulder Capsules Are Thicker and Stiffer in the Throwing Shoulders of Healthy College Baseball Players: A Quantitative Assessment Using Shear-Wave Ultrasound Elastography.

    PubMed

    Takenaga, Tetsuya; Sugimoto, Katsumasa; Goto, Hideyuki; Nozaki, Masahiro; Fukuyoshi, Masaki; Tsuchiya, Atsushi; Murase, Atsunori; Ono, Tetsuya; Otsuka, Takanobu

    2015-12-01

    Posterior and posteroinferior capsules in the shoulder joints of throwing athletes have been reported to be thicker in throwing than nonthrowing shoulders, and this has a relationship to glenohumeral internal rotation deficit (GIRD). However, the stiffness of these thickened capsules has not been reported. Shear-wave ultrasound elastography is a new technology that can measure tissue elasticity quantitatively. The posterior and posteroinferior capsules are stiffer as well as thicker in the throwing shoulders of baseball players than in their nonthrowing shoulders. The thickness and elasticity of these capsules are inversely correlated with glenohumeral internal rotation. Cross-sectional study; Level of evidence, 3. Forty-five male college baseball players were examined. The thickness and elasticity of the posterior capsule beneath the infraspinatus and the posteroinferior capsule beneath the teres minor were measured using an ultrasonic device equipped with shear-wave elastographic technology. Glenohumeral internal rotation at 90° of shoulder abduction and humeral retrotorsion were also measured. The mean thickness and elasticity of the posterior capsule were significantly greater for the throwing compared with the nonthrowing shoulder (thickness: 1.34 vs 1.04 mm, respectively; elasticity: 40.0 vs 32.2 kPa, respectively; P < .001 for both). The mean thickness and elasticity of the posteroinferior capsule were also significantly greater in the throwing compared with the nonthrowing shoulder (thickness: 1.40 vs 1.04 mm, respectively; elasticity: 39.4 vs 31.6 kPa, respectively; P < .001 for both). After correcting the range of motion for bilateral differences in retrotorsion, correlation coefficients showed that posterior capsule thickness and elasticity (Pearson r = -0.43 and -0.56, respectively; P < .001 for both) and posteroinferior capsule thickness and elasticity (Pearson r = -0.51 and -0.52, respectively; P < .001 for both) were negatively correlated with the

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

    PubMed

    Thiele, Maja; Kjaergaard, Maria; Thielsen, Peter; Krag, Aleksander

    2015-10-13

    The risk and speed of progression from fibrosis to compensated and decompensated cirrhosis define the prognosis in liver diseases. Therefore, early detection and preventive strategies affect outcomes. Patients with liver disease have traditionally been diagnosed at an advanced stage of disease, in part due to lack of non-invasive markers. Ultrasound elastography to measure liver stiffness can potentially change this paradigm. The purpose of this review was therefore to summarize advances in the field of ultrasound elastography with focus on diagnosis of liver fibrosis, cirrhosis and clinically significant portal hypertension, techniques and limitations. Four types of ultrasound elastography exist, but there is scarce evidence comparing the different techniques. The majority of experience concern transient elastography for diagnosing fibrosis and cirrhosis in patients with chronic viral hepatitis C. That said, the role of elastography in other aetiologies such as alcoholic- and non-alcoholic liver fibrosis still needs clarification. Although elastography can be used to diagnose liver fibrosis and cirrhosis, its true potential lies in the possibility of multiple, repeated measurements that allow for treatment surveillance, continuous risk stratification and monitoring of complications. As such, elastography may be a powerful tool for personalized medicine. While elastography is an exciting technique, the nature of ultrasound imaging limits its applicability, due to the risk of failures and unreliable results. Key factors that limit the applicability of liver stiffness measurements are as follows: liver vein congestion, cholestasis, a recent meal, inflammation, obesity, observer experience and ascites. The coming years will show whether elastography will be widely adapted in general care.

  9. Endoscopic ultrasound-guided inoculation of transmissible venereal tumor in the colon: A large animal model for colon neoplasia

    PubMed Central

    Bhutani, Manoop S.; Uthamanthil, Rajesh; Suzuki, Rei; Shetty, Anil; Klumpp, Sherry A.; Nau, William; Stafford, Roger Jason

    2016-01-01

    Background: To develop and evaluate the feasibility of emerging interventions, animal models with accurate anatomical environment are required. Objectives: We aimed to establish a clinically relevant colorectal tumor model with canine transmissible venereal tumor (CTVT) utilizing endoscopic ultrasound (EUS) imaging guidance. Design: Survival study using a canine model. Setting: Endoscopic animal research laboratory at a tertiary cancer center. Materials and Methods: This study involved five canines. Interventions: A colorectal tumor model was established and evaluated in five canines under cyclosporine immune suppression. Under endoscopic imaging guidance, saline was injected into the submucosal layer forming a bleb. Subsequently, CTVT was inoculated into the bleb under EUS guidance. Endoscopy was the primary method of assessing tumor growth. Tumors developed in 60-130 days. Upon detection of lesions >1 cm, the animals were euthanized and the tumors were harvested for histopathological characterization. Main outcome measurements: Success rate of tumor growth. The presence or absence of vasculature inside tumors. Results: Colorectal tumor successfully developed in three out of the five animals (60%). Among the ones with tumor growth, average inoculated CTVT volume, incubation time, and tumor size was 1.8 cc, 65.7 days, and 2.0 cm, respectively. The two animals without tumor growth were observed for >100 days. In all the tumors, vascular structure was characterized with CD31 imunohistochemical stain. Limitations: Small number of animals. Conclusion: We succeeded in creating a new colorectal tumor canine model with CTVT utilizing EUS. PMID:27080606

  10. Hegemony and cost-effectiveness of endoscopic ultrasound (EUS) in the field of gastroenteropancreatic-neuroendocrine tumors (GEP-NETs).

    PubMed

    De Angelis, C; Manfrè, S F; Bruno, M; Pellicano, R

    2014-10-01

    Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are a group of neoplasms arising from the diffuse neuroendocrine system of the gastrointestinal (GI) tract. They often represent a diagnostic challenge because of their little dimensions, the deep localization into the retroperitoneum or in extramucosal sites, the possibility to be multilocated and the heterogeneous patterns of presentation. Endoscopic ultrasound (EUS) is a cost-effective technique that enables to look very definitely at a suspicious mass and at the surrounding area both within the GI wall and in the pancreas, allowing to precisely assess T and N stage. Under EUS-guidance it is possible to obtain tissue samples in order to reach a definitive diagnosis and to establish the tumor grade. In the therapeutic field, EUS is crucial to assess the safety and the feasibility of resective endoscopic techniques for the GI-wall NETs and it can guide local ablative techniques for pancreatic NETs. After treatment, EUS can be successfully useful to assess complete endoscopic resection and to follow-up resected or ablated patients. It is so evident that EUS has a role in the whole route of NETs management, from diagnosis, evaluation, grading and staging assessment, to therapy and consequent follow-up.

  11. Endoscopic Ultrasound-Guided Biliary Drainage: A Systematic Review and Meta-Analysis.

    PubMed

    Khan, Muhammad Ali; Akbar, Ali; Baron, Todd H; Khan, Sobia; Kocak, Mehmat; Alastal, Yaseen; Hammad, Tariq; Lee, Wade M; Sofi, Aijaz; Artifon, Everson L A; Nawras, Ali; Ismail, Mohammad Kashif

    2016-03-01

    Variable success and adverse event rates have been reported for endoscopic ultrasound-guided biliary drainage (EUS-BD) utilizing either extrahepatic or intrahepatic approach. We aimed to conduct a proportion meta-analysis to evaluate the cumulative efficacy and safety of EUS-BD and to compare the two approaches and transluminal methods of EUS-BD. We searched MEDLINE, Embase, Cochrane Central Register of Controlled Trials, ISI Web of Science, and Scopus from January 2001 through January 5, 2015, to identify studies reporting technical success and adverse events of EUS-BD. A sample size of more than 20 patients was a further criterion. Weighted pooled rate (WPR) for technical success and post-procedure complications was calculated for overall studies and predefined subgroups. Pooled odds ratios were calculated for technical success and adverse events for two approaches and transluminal methods of EUS-BD for distal common bile duct (CBD) strictures. The WPR with 95% confidence interval (CI) for technical success and post-procedure adverse events was 90% (86, 93%) and 17% (13, 22%), respectively, with considerable heterogeneity (I(2) = 77%). For high-quality studies, the WPR for technical success was 94% (91, 96 %), I(2) = 0% and WPR for post-procedure adverse event was 16% (12, 19%), I(2) = 39%. In meta-regression model, distal CBD stricture and transpapillary drainage were associated with higher technical success and intrahepatic access route was associated with higher adverse event rate. There was no difference in technical success using either approach OR 1.27 (0.52, 3.13), I(2) = 0% or transluminal method OR 1.32 (0.51, 3.38), I(2) = 0%. However, the extrahepatic approach appeared significantly safer as compared to the intrahepatic approach OR 0.35 (0.19, 0.67), I(2) = 27%. Likewise, choledochoduodenostomy was found to have less adverse events as compared to hepaticogastrostomy, OR 0.40 (0.18, 0.87), I (2) = 0%. In cases of failure of traditional ERC to achieve

  12. Sampling of the adrenal glands by endoscopic ultrasound-guided fine-needle aspiration.

    PubMed

    Stelow, Edward B; Debol, Steven M; Stanley, Michael W; Mallery, Shawn; Lai, Rebecca; Bardales, Ricardo H

    2005-07-01

    Endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA) has proven to be a valuable modality for the primary diagnosis and staging of gastrointestinal, and perigastrointestinal malignancy. Aside from assessing thoracic and abdominal lymph nodes and the liver for metastases, EUS can assess and sample the adrenal glands, which are frequently involved by metastatic disease, but can also harbor benign primary neoplasms. The cytology files at our institution were reviewed for all cases of EUS-guided FNA of the adrenal glands. Clinical histories, sonographic findings, and cytologic findings of all cases were reviewed. Results were compared with overall EUS-guided FNA performance and the performance of non-EUS-guided FNA of the adrenal. The utility of cell block immunohistochemistry (IHC) in these cases was reviewed. Between 1/1/00 and 5/15/04 there were 24 cases of EUS-guided FNA of the adrenal gland from 22 different patients (13 men; 9 women) at our institution. This represented 1.4% of overall EUS-guided FNA and 77% of adrenal gland FNA. Patient ages ranged from 37 to 86 yr (mean 69 +/- 11 yr). Most patients had other cancers or mass lesions and were being staged at the time of the procedure (19 of 22). Almost all FNAs were of the left adrenal gland (23 of 24). Lesion size ranged from 0.9 to 7.9 cm (mean 2.5 +/- 1.6 cm). Diagnostic material was present in all cases when compared with an overall EUS-guided FNA diagnostic rate of 88%. Material for cell block was present in 21 cases, and IHC was used in 3 cases. Final diagnoses were as follows: cortical tissue consistent with cortical adenoma (19), metastatic adenocarcinoma (3), pheochromocytoma (1), and adrenal cortical carcinoma (1). EUS-guided FNA of the adrenal gland is primarily used in the staging of other malignancies when lesions of the left adrenal are recognized sonographically. Diagnostic tissue is easily obtained, including material for cell block IHC, which allows definitive diagnosis in cases that

  13. Role of endoscopic ultrasound-guided fine needle aspiration in the diagnosis of mass lesions

    PubMed Central

    Han, Chaoqun; Lin, Rong; Zhang, Qin; Liu, Jun; Ding, Zhen; Hou, Xiaohua

    2016-01-01

    Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is an accurate technique for sampling the pancreas and mediastinum; however, limited data are available for other mass lesions. The aim of this study was to explore the value of EUS-FNA in the differential diagnosis of all mass lesions. Data from patients who underwent EUS-FNA for the diagnosis of mass lesions, including pancreatic, mediastinal, celiac and retroperitoneal lesions were retrospectively analyzed. The accuracy was calculated by comparing the results of FNA with the results of pathological examination or follow-up surveillances in non-operated cases. A total of 150 cases were included. The location of the mass varied from the pancreas (n=62) to the mediastinum (n=29), gastrointestinal tract (n=36), celiac cavity and retroperitoneum (n=23). The sensitivity and Youdens index of EUS-FNA in the diagnosis of all lesions were 92.97% and 0.93 respectively. The accuracy of diagnosis of pancreatic, mediastinal, gastrointestinal, celiac and retroperitoneal lesions was 85.48, 89.66, 83.33 and 78.23%, respectively. Masses were categorized into parenchymal organs (n=66), luminal organs (n=36) and enlarged lymph nodes (n=33). Lesions in parenchymal organs were likely to be bigger than those in luminal organs (P=0.03) and enlarged lymph nodes (P=0.01). For solid and cystic masses, which constituted 63.3 and 14.7% of the total masses, no significant difference in diagnostic accuracy was observed (P=0.56); however, lesion sizes were significantly different between these two groups (P=0.04) and the majority of cystic masses were identified in women (P=0.03). Malignant lesions were more common in older (P=0.01) and male (P=0.03) patients. In conclusion, EUS-FNA is an effective tool in the diagnosis of unexplained mass lesions; it influences the management of patients by enabling the appropriate treatment to be identified. PMID:27446324

  14. Repeat endoscopic ultrasound fine needle aspiration after a first negative procedure is useful in pancreatic lesions

    PubMed Central

    Téllez-Ávila, Félix I.; Martínez-Lozano, Jorge Adolfo; Rosales-Salinas, Anamaría; Bernal-Méndez, Ambrosio Rafael; Guerrero-Velásquez, Camilo; Ramírez-Luna, Miguel Ángel; Valdovinos-Andraca, Francisco

    2016-01-01

    Background and Objectives: There is no consensus about the ideal method for diagnosis in patients who have already undergone endoscopic ultrasound fine needle aspiration (EUS-FNA), and the inconclusive material is often obtained. The aim was to evaluate the diagnostic yield of the second EUS-FNA of pancreatic lesions. Materials and Methods: A retrospective analysis of prospectively collected data of patients with EUS-FNA of pancreatic lesions is performed. All patients who underwent more than one EUS-FNA for the evaluation of suspected pancreatic cancer over a 7-year period were included in the analysis. Results: A total of 296 EUS-FNAs of the pancreas were performed in 257 patients. The diagnostic yield with the first EUS-FNA was 78.6% (202/257). Thirty-nine (13.3%) FNAs were repeated in 34 patients; 17 (50%) patients were women. The mean ± standard deviation (SD) age was 58.8 ± 16.1 years. The location of the lesions in the pancreatic gland, from which the second biopsies were taken, was head of the pancreas, n = 28 (82.4%), body of the pancreas, n = 3 (8.8%), and tail, n = 3 (8.8%). The mean ± SD of the size of the lesion was 36.3 ± 14.6 mm. The second EUS-FNA was more likely to be positive for diagnosis in patients with an “atypical“ histological result in the first EUS-FNA (odds ratio [OR]: 4.04; 95% confidence interval [CI]: 0.9–18.3), in contrast to patients with a first EUS-FNA reported as “normal” (OR: 0.21; 95% CI: 0.06–0.71). Overall, the diagnostic yield of the second EUS-FNA was 58.8% (20/34) with an increase to 86.3% overall (222/257). Conclusion: Repeat EUS-FNA in pancreatic lesions is necessary in patients with a negative first EUS-FNA because it improves the diagnostic yield. PMID:27503159

  15. Endoscopic ultrasound-guided fine-needle aspiration for suspected malignancies adjacent to the gastrointestinal tract.

    PubMed

    Gambitta, Pietro; Armellino, Antonio; Forti, Edoardo; Vertemati, Maurizio; Colombo, Paola Enrica; Aseni, Paolo

    2014-07-14

    To investigate the impact of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) in association with a multidisciplinary team evaluation for the detection of gastrointestinal malignancies. A cohort of 1019 patients with suspected malignant lesions adjacent to the gastrointestinal tract received EUS-FNA after a standardized multidisciplinary team evaluation (MTE) and were divided into 4 groups according to their specific malignant risk score (MRS). Patients with a MRS of 0 (without detectable risk of malignancy) received only EUS without FNA. For patients with a MRS score ranging from 1 (low risk) - through 2 (intermediate risk) - to 3 (high risk), EUS-FNA cytology of the lesion was planned for a different time and was prioritized for those patients at higher risk for cancer. The accuracy, efficiency and quality assessment for the early detection of patients with potentially curable malignant lesions were evaluated for the whole cohort and in the different classes of MRSs. The time to definitive cytological diagnosis (TDCD), accuracy, sensitivity, specificity, positive and negative predictive values, and the rate of inconclusive tests were calculated for all patients and for each MRS group. A total of 1019 patients with suspected malignant lesions were evaluated by EUS-FNA. In 515 patients of 616 with true malignant lesions the tumor was diagnosed by EUS-FNA; 421 patients with resectable lesions received early surgical treatment, and 94 patients received chemo-radiotherapy. The overall diagnostic accuracy for the 1019 lesions in which a final diagnosis was obtained by EUS-FNA was 0.95. When patients were stratified by MTE into 4 classes of MRSs, a higher rate of patients in the group with higher cancer risk (MRS-3) received early treatment and EUS-FNA showed the highest level of accuracy (1.0). TDCD was also shorter in the MRS-3 group. The number of patients who received surgical treatment or chemo-radiotherapy was significantly higher in the MRS-3 patient

  16. Endoscopic ultrasound-guided fine-needle aspiration for suspected malignancies adjacent to the gastrointestinal tract

    PubMed Central

    Gambitta, Pietro; Armellino, Antonio; Forti, Edoardo; Vertemati, Maurizio; Colombo, Paola Enrica; Aseni, Paolo

    2014-01-01

    AIM: To investigate the impact of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) in association with a multidisciplinary team evaluation for the detection of gastrointestinal malignancies. METHODS: A cohort of 1019 patients with suspected malignant lesions adjacent to the gastrointestinal tract received EUS-FNA after a standardized multidisciplinary team evaluation (MTE) and were divided into 4 groups according to their specific malignant risk score (MRS). Patients with a MRS of 0 (without detectable risk of malignancy) received only EUS without FNA. For patients with a MRS score ranging from 1 (low risk) - through 2 (intermediate risk) - to 3 (high risk), EUS-FNA cytology of the lesion was planned for a different time and was prioritized for those patients at higher risk for cancer. The accuracy, efficiency and quality assessment for the early detection of patients with potentially curable malignant lesions were evaluated for the whole cohort and in the different classes of MRSs. The time to definitive cytological diagnosis (TDCD), accuracy, sensitivity, specificity, positive and negative predictive values, and the rate of inconclusive tests were calculated for all patients and for each MRS group. RESULTS: A total of 1019 patients with suspected malignant lesions were evaluated by EUS-FNA. In 515 patients of 616 with true malignant lesions the tumor was diagnosed by EUS-FNA; 421 patients with resectable lesions received early surgical treatment, and 94 patients received chemo-radiotherapy. The overall diagnostic accuracy for the 1019 lesions in which a final diagnosis was obtained by EUS-FNA was 0.95. When patients were stratified by MTE into 4 classes of MRSs, a higher rate of patients in the group with higher cancer risk (MRS-3) received early treatment and EUS-FNA showed the highest level of accuracy (1.0). TDCD was also shorter in the MRS-3 group. The number of patients who received surgical treatment or chemo-radiotherapy was significantly

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

    PubMed

    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.

  18. Two-dimensional ultrasound and ultrasound elastography imaging of trigger points in women with myofascial pain syndrome treated by acupuncture and electroacupuncture: a double-blinded randomized controlled pilot study.

    PubMed

    Müller, Cristina Emöke Erika; Aranha, Maria Fernanda Montans; Gavião, Maria Beatriz Duarte

    2015-04-01

    Chronic pain has been often associated with myofascial pain syndrome (MPS), which is determined by myofascial trigger points (MTrP). New features have been tested for MTrP diagnosis. The aim of this study was to evaluate two-dimensional ultrasonography (2D US) and ultrasound elastography (UE) images and elastograms of upper trapezius MTrP during electroacupuncture (EA) and acupuncture (AC) treatment. 24 women participated, aged between 20 and 40 years (M ± SD = 27.33 ± 5.05) with a body mass index ranging from 18.03 to 27.59 kg/m2 (22.59 ± 3.11), a regular menstrual cycle, at least one active MTrP at both right (RTPz) and left trapezius (LTPz) and local or referred pain for up to six months. Subjects were randomized into EA and AC treatment groups and the control sham AC (SHAM) group. Intensity of pain was assessed by visual analogue scale; MTrP mean area and strain ratio (SR) by 2D US and UE. A significant decrease of intensity in general, RTPz, and LTPz pain was observed in the EA group (p = 0.027; p < 0.001; p = 0.005, respectively) and in general pain in the AC group (p < 0.001). Decreased MTrP area in RTPz and LTPz were observed in AC (p < 0.001) and EA groups (RTPz, p = 0.003; LTPz, p = 0.005). Post-treatment SR in RTPz and LTPz was lower than pre-treatment in both treatment groups. 2D US and UE effectively characterized MTrP and surrounding tissue, pointing to the possibility of objective confirmation of subjective EA and AC treatment effects. © The Author(s) 2014.

  19. Sonographic Elastography of the Thyroid Gland

    PubMed Central

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

    2016-01-01

    Summary Thyroid gland disorders include benign and malignant thyroid nodules and diffuse thyroid disorders. The incidence of malignant thyroid nodules is low and the prognosis is good. The diagnosis of thyroid cancer and diffuse parenchymal disorders is generally based on clinical manifestations and histopathological evaluation. Ultrasonography has its place in the diagnostics and follow-up of thyroid disorders. Ultrasonographic elastography is a new, developing method that shows increase in clinical practice. In this study, we aimed to review the data on thyroid ultrasound elastography. PMID:27103947

  20. Texture generation in compressional photoacoustic elastography

    NASA Astrophysics Data System (ADS)

    Schmid, J. W.; Zabihian, B.; Widlak, T.; Glatz, T.; Liu, M.; Drexler, W.; Scherzer, O.

    2015-03-01

    Elastography is implemented by applying a mechanical force to a specimen and visualizing the resulting displacement. As a basis of elastographic imaging typically ultrasound, optical coherence tomography or magnetic resonance imaging are used. Photoacoustics has not been viewed as a primary imaging modality for elastography, but only as a complementary method to enhance the contrast in ultrasound elastography. The reason is that photoacoustics is considered speckle free [3], which hinders application of speckle tracking algorithms. However, while conventional ultrasound only uses a single frequency, photoacoustics utilizes a broad frequency spectrum. We are therefore able to generate artificial texture by using a frequency band limited part of the recorded data. In this work we try to assess the applicability of this technique to photoacoustic tomography. We use Agar phantoms with predefined Young's moduli and laterally apply a 50μm static compression. Pre- and post compression data are recorded via a Fabry Pérot interferometer planar sensor setup and reconstructed via a non-uniform-FFT reconstruction algorithm. A displacement vector field, between pre- and post compressed data is then determined via optical flow algorithms. While the implementation of texture generation during post processing reduces image quality overall, it turns out that it improves the detection of moving patterns and is therefore better suited for elastography.

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

    PubMed

    Park, So Hyun; Kim, So Yeon; Suh, Chong Hyun; Lee, Seung Soo; Kim, Kyoung Won; Lee, So Jung; Lee, Moon-Gyu

    2016-09-01

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

  2. High-flow nasal oxygen availability for sedation decreases the use of general anesthesia during endoscopic retrograde cholangiopancreatography and endoscopic ultrasound.

    PubMed

    Schumann, Roman; Natov, Nikola S; Rocuts-Martinez, Klifford A; Finkelman, Matthew D; Phan, Tom V; Hegde, Sanjay R; Knapp, Robert M

    2016-12-21

    To examine whether high-flow nasal oxygen (HFNO) availability influences the use of general anesthesia (GA) in patients undergoing endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic ultrasound (EUS) and associated outcomes. In this retrospective study, patients were stratified into 3 eras between October 1, 2013 and June 30, 2014 based on HFNO availability for deep sedation at the time of their endoscopy. During the first and last 3-mo eras (era 1 and 3), no HFNO was available, whereas it was an option during the second 3-mo era (era 2). The primary outcome was the percent utilization of GA vs deep sedation in each period. Secondary outcomes included oxygen saturation nadir during sedation between periods, as well as procedure duration, and anesthesia-only time between periods and for GA vs sedation cases respectively. During the study period 238 ERCP or EUS cases were identified for analysis. Statistical testing was employed and a P < 0.050 was significant unless the Bonferroni correction for multiple comparisons was used. General anesthesia use was significantly lower in era 2 compared to era 1 with the same trend between era 2 and 3 (P = 0.012 and 0.045 respectively). The oxygen saturation nadir during sedation was significantly higher in era 2 compared to era 3 (P < 0.001) but not between eras 1 and 2 (P = 0.028) or 1 and 3 (P = 0.069). The procedure time within each era was significantly longer under GA compared to deep sedation (P ≤ 0.007) as was the anesthesia-only time (P ≤ 0.001). High-flow nasal oxygen availability was associated with decreased GA utilization and improved oxygenation for ERCP and EUS during sedation.

  3. High-flow nasal oxygen availability for sedation decreases the use of general anesthesia during endoscopic retrograde cholangiopancreatography and endoscopic ultrasound

    PubMed Central

    Schumann, Roman; Natov, Nikola S; Rocuts-Martinez, Klifford A; Finkelman, Matthew D; Phan, Tom V; Hegde, Sanjay R; Knapp, Robert M

    2016-01-01

    AIM To examine whether high-flow nasal oxygen (HFNO) availability influences the use of general anesthesia (GA) in patients undergoing endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic ultrasound (EUS) and associated outcomes. METHODS In this retrospective study, patients were stratified into 3 eras between October 1, 2013 and June 30, 2014 based on HFNO availability for deep sedation at the time of their endoscopy. During the first and last 3-mo eras (era 1 and 3), no HFNO was available, whereas it was an option during the second 3-mo era (era 2). The primary outcome was the percent utilization of GA vs deep sedation in each period. Secondary outcomes included oxygen saturation nadir during sedation between periods, as well as procedure duration, and anesthesia-only time between periods and for GA vs sedation cases respectively. RESULTS During the study period 238 ERCP or EUS cases were identified for analysis. Statistical testing was employed and a P < 0.050 was significant unless the Bonferroni correction for multiple comparisons was used. General anesthesia use was significantly lower in era 2 compared to era 1 with the same trend between era 2 and 3 (P = 0.012 and 0.045 respectively). The oxygen saturation nadir during sedation was significantly higher in era 2 compared to era 3 (P < 0.001) but not between eras 1 and 2 (P = 0.028) or 1 and 3 (P = 0.069). The procedure time within each era was significantly longer under GA compared to deep sedation (P ≤ 0.007) as was the anesthesia-only time (P ≤ 0.001). CONCLUSION High-flow nasal oxygen availability was associated with decreased GA utilization and improved oxygenation for ERCP and EUS during sedation. PMID:28058020

  4. Creation of multiple transluminal gateway during endoscopic ultrasound-guided drainage of pancreatic necrosis by enlarging tract of impending rupture in duodenum

    PubMed Central

    Rana, Surinder Singh; Sharma, Vishal; Gorka, Suresh; Sharma, Ravi; Bhasin, Deepak Kumar

    2015-01-01

    Necrotic pancreatic collections are difficult to treat endoscopically due to a concern for inadequate drainage of the necrotic debris. Multiple techniques including the use of metallic stents, endoscopic necrosectomy and use of hybrid approaches utilizing endoscopic and percutaneous approaches have been described for the management of pancreatic necrotic collections. Furthermore, multiple transluminal gateway technique has been used to create endosonography guided multiple tracts to drain a perigastric or periduodenal collection. We hereby report about a patient with walled off necrosis resulting as a complication of alcohol related acute pancreatitis that was drained using endoscopic ultrasound-guided approach. However, a spontaneous cystoduodenal fistula was used to create another tract and place transmural stents resulting in a quick resolution of symptoms. PMID:26374587

  5. Breast Ultrasound: Indications and Findings.

    PubMed

    Gundry, Kathleen R

    2016-06-01

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

  6. Pancreatic and Gastric Plasmacytoma Presenting with Obstructive Jaundice, Diagnosed with Endoscopic Ultrasound-Guided Fine Needle Aspiration.

    PubMed

    Padda, Manmeet S; Milless, Tiffani; Adeniran, Adebowale J; Mahooti, Sepi; Aslanian, Harry R

    2010-09-28

    Pancreatic plasmacytoma is a rare disorder which may present with obstructive jaundice. Only eighteen cases have been reported in the English language literature. We present the first case of pancreatic plasmacytoma and gastric plasmacytoma diagnosed with endoscopic ultrasound-guided fine needle aspiration (EUS-FNA). A 75-year-old male with a known history of multiple myeloma presented with obstructive jaundice and a pancreatic mass. A concomitant gastric mass due to gastric plasmacytoma was seen. The diagnosis was established via EUS-FNA of the pancreatic mass. Pancreatic plasmacytoma should be suspected in patients with a history of myeloma. EUS-FNA is a safe and effective modality in the diagnosis of pancreatic plasmacytoma. Radiation therapy should be the first-line of therapy in treating pancreatic plasmacytomas.

  7. Pancreatic and Gastric Plasmacytoma Presenting with Obstructive Jaundice, Diagnosed with Endoscopic Ultrasound-Guided Fine Needle Aspiration

    PubMed Central

    Padda, Manmeet S.; Milless, Tiffani; Adeniran, Adebowale J.; Mahooti, Sepi; Aslanian, Harry R.

    2010-01-01

    Pancreatic plasmacytoma is a rare disorder which may present with obstructive jaundice. Only eighteen cases have been reported in the English language literature. We present the first case of pancreatic plasmacytoma and gastric plasmacytoma diagnosed with endoscopic ultrasound-guided fine needle aspiration (EUS-FNA). A 75-year-old male with a known history of multiple myeloma presented with obstructive jaundice and a pancreatic mass. A concomitant gastric mass due to gastric plasmacytoma was seen. The diagnosis was established via EUS-FNA of the pancreatic mass. Pancreatic plasmacytoma should be suspected in patients with a history of myeloma. EUS-FNA is a safe and effective modality in the diagnosis of pancreatic plasmacytoma. Radiation therapy should be the first-line of therapy in treating pancreatic plasmacytomas. PMID:21060710

  8. Endoscopic Ultrasound-Guided Fine-Needle Aspiration of Pancreatic Lesions: A Systematic Review of Technical and Procedural Variables.

    PubMed

    Jani, Bhairvi S; Rzouq, Fadi; Saligram, Shreyas; Lim, Diego; Rastogi, Amit; Bonino, John; Olyaee, Mojtaba

    2016-01-01

    Endoscopic ultrasound (EUS)-guided tissue acquisition has emerged over the last decade as an invaluable diagnostic tool in approaching the different pancreatic lesions. Given the safety and minimal invasiveness of this approach combined with the high diagnostic yield, it became the standard of care when dealing with different pancreatic pathologies. However, some variables regarding this procedure remain not fully understood. These can influence the diagnostic yield of the procedure and include the presence of the on-site cytopathologist, the type and size of the needle used as well as obtaining aspiration versus core biopsy, the number of passes and the sampling technique, and the role of suction and stylet use among others. We performed a comprehensive literature search using PubMed, Google Scholar, and Embase for studies that assessed these variables. Eligible studies were analyzed using several parameters such as technique and procedure, with the aim of reviewing results from an evidence-based standpoint.

  9. Integration of single-fiber reflectance spectroscopy into ultrasound-guided endoscopic lung cancer staging of mediastinal lymph nodes.

    PubMed

    Kanick, Stephen Chad; van der Leest, Cor; Aerts, Joachim G J V; Hoogsteden, Henk C; Kascáková, Slávka; Sterenborg, Henricus J C M; Amelink, Arjen

    2010-01-01

    We describe the incorporation of a single-fiber reflectance spectroscopy probe into the endoscopic ultrasound fine-needle aspiration (EUS-FNA) procedure utilized for lung cancer staging. A mathematical model is developed to extract information about the physiological and morphological properties of lymph tissue from single-fiber reflectance spectra, e.g., microvascular saturation, blood volume fraction, bilirubin concentration, average vessel diameter, and Mie slope. Model analysis of data from a clinical pilot study shows that the single-fiber reflectance measurement is capable of detecting differences in the physiology between normal and metastatic lymph nodes. Moreover, the clinical data show that probe manipulation within the lymph node can perturb the in vivo environment, a concern that must be carefully considered when developing a sampling strategy. The data show the feasibility of this novel technique; however, the potential clinical utility has yet to be determined.

  10. The value of endoscopic ultrasound in a 47-year-old man with cystic lesions of the liver and pancreas.

    PubMed

    Mohammad Alizadeh, Amir Houshang; Parhizkar, Baran; Rajabalinia, Hassan

    2014-01-01

    Most neuroendocrine tumors (NETs), like other tumors, are clinically silent, producing symptoms only as a consequence of tumor growth. Pancreatic NETs account for only 1% of pancreatic cancers by incidence, while representing 10% of all pancreatic cancers by 28-year limited duration prevalence. Here, we present a 47-year-old man with abdominal pain, icterus, itching and 8 kg weight loss during 5 months. Elevated liver enzymes, direct bilirubin and alkaline phosphatase were observed. Magnetic resonance cholangiopancreatography showed a prominence at the head of the pancreas and also liver cysts. Endoscopic ultrasound of the pancreas was performed and a specimen was obtained via fine needle aspiration. Immunohistochemical staining was performed and the result was compatible with NET. The patient referred to receive chemotherapy.

  11. Integration of single-fiber reflectance spectroscopy into ultrasound-guided endoscopic lung cancer staging of mediastinal lymph nodes

    NASA Astrophysics Data System (ADS)

    Kanick, Stephen Chad; van der Leest, Cor; Aerts, Joachim G. J. V.; Hoogsteden, Henk C.; Kaščáková, Slávka; Sterenborg, Henricus J. C. M.; Amelink, Arjen

    2010-01-01

    We describe the incorporation of a single-fiber reflectance spectroscopy probe into the endoscopic ultrasound fine-needle aspiration (EUS-FNA) procedure utilized for lung cancer staging. A mathematical model is developed to extract information about the physiological and morphological properties of lymph tissue from single-fiber reflectance spectra, e.g., microvascular saturation, blood volume fraction, bilirubin concentration, average vessel diameter, and Mie slope. Model analysis of data from a clinical pilot study shows that the single-fiber reflectance measurement is capable of detecting differences in the physiology between normal and metastatic lymph nodes. Moreover, the clinical data show that probe manipulation within the lymph node can perturb the in vivo environment, a concern that must be carefully considered when developing a sampling strategy. The data show the feasibility of this novel technique; however, the potential clinical utility has yet to be determined.

  12. Core needle versus standard needle for endoscopic ultrasound-guided biopsy of solid pancreatic masses: a randomized crossover study.

    PubMed

    Vanbiervliet, Geoffroy; Napoléon, Bertrand; Saint Paul, Marie Christine; Sakarovitch, Charlotte; Wangermez, Marc; Bichard, Philippe; Subtil, Clément; Koch, Stéphane; Grandval, Philippe; Gincul, Rodica; Karsenti, David; Heyries, Laurent; Duchmann, Jean-Christophe; Bourgaux, Jean François; Levy, Michaël; Calament, Gilles; Fumex, Fabien; Pujol, Bertrand; Lefort, Christine; Poincloux, Laurent; Pagenault, Maël; Bonin, Eduardo Aimé; Fabre, Monique; Barthet, Marc

    2014-12-01

    A new core biopsy needle for endoscopic ultrasound (EUS)-guided sampling has recently been developed. The aim of this prospective multicenter study was to compare this needle with a standard needle in patients with solid pancreatic masses. Consecutive patients with solid pancreatic masses referred to 17 centers for EUS-guided sampling were included. Each patient had two passes with a standard 22G needle and a single pass with a 22G core needle performed in a randomized order. Samples from both needles were separately processed for liquid-based cytology and cell-block preparation and were assessed independently by two blinded expert pathologists. The primary endpoint was the accuracy of the detection of malignancy. The reference standard was based on further cytohistological analysis obtained under ultrasound or computed tomography scanning, endoscopic or surgical guidance, and/or by clinical follow-up with repeated imaging examinations for at least 12 months. The secondary endpoints were the rate of technical failure and the quality of the cytohistological samples obtained. Of the 80 patients included (49 men; mean age 67.1 ± 11.1), 87.5 % had final malignant diagnoses (adenocarcinoma n = 62, 77.5 %). There was no difference between the needles in diagnostic accuracy (standard needle 92.5 % vs. core needle 90 %; P = 0.68) or technical failure. Both pathologists found the overall sample quality significantly better for the standard needle (expert 1, P = 0.009; expert 2, P = 0.002). The diagnostic accuracy of EUS sampling for solid pancreatic masses using standard and core needles seems comparable but with a better overall histological sample quality for the former. ClinicalTrial.gov identifier: NCT01479803. © Georg Thieme Verlag KG Stuttgart · New York.

  13. Endoscopic ultrasound-guided forceps biopsy from upper gastrointestinal subepithelial lesions using a forward-viewing echoendoscope

    PubMed Central

    Matsuzaki, Ippei; Miyahara, Ryoji; Hirooka, Yoshiki; Funasaka, Kohei; Yamamura, Takeshi; Ohno, Eizaburo; Nakamura, Masanao; Kawashima, Hiroki; Watanabe, Osamu; Kobayashi, Makoto; Shimoyama, Yoshie; Nakamura, Shigeo; Goto, Hidemi

    2016-01-01

    Background and study aims: Endoscopic tissue acquisition techniques using needle-knife and biopsy forceps allow abundant tissue acquisition from upper gastrointestinal subepithelial lesions; however, these techniques cannot capture real-time intratumor information. The aim of this study was to evaluate the feasibility of endoscopic ultrasound-guided forceps biopsy (EUS-FB) from upper gastrointestinal subepithelial lesions using a forward-viewing echoendoscope. Patients and methods: This study was a prospective case series. After mucosal cuts, several specimens were taken using a hot biopsy forceps under real-time EUS visualization. The incision was closed using hemoclips. Diagnostic yield, rate of diagnosable samples obtained under EUS visualization, procedure time, and adverse events were assessed. Results: Ten patients (median lesion size 16 mm, range 15 – 44 mm) underwent EUS-FB. The overall rate of histological diagnosis by EUS-FB was 100 % (10/10). The rate of diagnosable samples among all cases was 97.6 % (41/42). The median procedure times for EUS-FB and complete closure were 28.5 and 4.5 minutes, respectively. No adverse events occurred. Conclusions: This newly developed EUS-FB is feasible and allowed forceps biopsy from upper gastrointestinal subepithelial lesions. Study registration: UMIN000015364 PMID:27556070

  14. Multicentric solid pseudopapillary neoplasms of the pancreas diagnosed by endoscopic ultrasound-guided fine needle aspiration: a case report.

    PubMed

    Yamaguchi, Megumi; Fukuda, Toshikatsu; Nakahara, Masahiro; Amano, Mio; Takei, Daisuke; Kawashima, Masumi; Sumi, Yusuke; Amano, Hironobu; Yonehara, Shuji; Hanada, Keiji; Noriyuki, Toshio

    2015-12-01

    Solid pseudopapillary neoplasm (SPN) of the pancreas is a rare tumor. This neoplasm usually arises as a single mass; multicentricity is exceptionally rare. We report the preoperative diagnosis of multicentric SPNs by endoscopic ultrasound-guided fine needle aspiration (EUS-FNA). A 32-year-old woman presented to the hospital with a pancreatic tumor that was detected on abdominal echography. Contrast-enhanced computed tomography (CT) scans revealed a 5-mm low-density mass in the body of the pancreas and a 10-mm mass in the tail of the pancreas. Magnetic resonance imaging (MRI) also revealed two tumors in the body and tail of the pancreas. On endoscopic ultrasonography (EUS), two indistinct and heterogeneous echogenic masses were found, and EUS-FNA was performed for each of these tumors. Cytological analysis revealed that the two masses were highly cellular with papillary groups of small, uniform, oval cells surrounding a fibrovascular core. Immunohistochemistry was positive for α-1 antitrypsin, vimentin, neuron-specific enolase (NSE), CD10, and progesterone receptor. These features confirmed the preoperative diagnosis of multicentric SPNs. The patient underwent laparoscopic distal pancreatectomy with splenectomy. The final pathologic diagnosis was multicentric SPNs. During 2 years of follow-up, she has not developed any recurrence.

  15. Prostate elastography: preliminary in vivo results

    NASA Astrophysics Data System (ADS)

    Alam, S. K.; Feleppa, E. J.; Kalisz, A.; Ramchandran, S.; Ennis, R. D.; Lizzi, Frederick L.; Wuu, C.-S.; Ketterling, Jeffrey A.

    2005-04-01

    We report preliminary results from our investigation of in vivo prostate elastography. Fewer than 50% of all prostate cancers are typically visible in current clinical imaging modalities. Elastography displays a map of strain that results when tissue is externally compressed. Thus, elastography is ideal for imaging prostate cancers because they are generally stiffer than the surrounding tissue and stiffer regions usually exhibit lower strain in elastograms. In our study, digital radio-frequency (RF) ultrasound echo data were acquired from prostate-cancer patients undergoing brachytherapy. Seed placement is guided by a transrectal ultrasound (TRUS) probe, which is held in a mechanical fixture. The probe can be moved in XYZ directions and tilted. The probe face, in contact with the rectal wall, is used to apply a compression force to the immediately adjacent prostate. We also used a water-filled (acoustic) coupling balloon to compress the prostate by increasing the water volume inside the balloon. In each scan plane (transverse), we acquired RF data from successive scans at the scanner frame rate as the deformation force on the rectal wall was continuously increased. We computed strain using 1D RF cross-correlation analysis. The compression method based on fixture displacement produced low-noise elastograms that beautifully displayed the prostate architecture and emphasized stiff areas. Balloon-based compression also produced low-noise elastograms. Initial results demonstrate that elastography may be useful in the detection and evaluation of prostate cancers, occult in conventional imaging modalities.

  16. Comparison of Ultrasound-Guided Core Needle Biopsy and Endoscopic Ultrasound-Guided Fine-Needle Aspiration for Solid Pancreatic Lesions.

    PubMed

    Sur, Young Keun; Kim, Young Chul; Kim, Jai Keun; Lee, Jei Hee; Yoo, Byung Moo; Kim, Young Bae

    2015-12-01

    The objective of our study was to compare the diagnostic yield of endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA) using a 25-gauge needle and ultrasound (US)-guided core needle biopsy (CNB) using an 18-gauge core needle for diagnosis of solid pancreatic lesions. This retrospective study was approved by our Institutional Review Board, and the requirement for informed consent was waived. Patients who underwent either EUS-guided FNA or US-guided CNB for a solid pancreatic lesion from January 2008 to December 2012 were included and reviewed. Fine-needle aspirations and CNBs were performed by experienced endoscopists and radiologists. The diagnostic yield, accuracy, technical failure rate, sensitivity, and specificity for malignancy were calculated and compared. A total of 106 biopsy attempts were undertaken in 89 patients (EUS-guided FNA, n = 70; US-guided CNB, n = 36). Biopsy specimens were successfully obtained in 98 biopsy attempts (EUS-guided FNA, n = 63; US-guided CNB, n = 35). The accuracy, technical failure rate, sensitivity, and specificity of EUS-guided FNA for malignancy (73.02%, 10.00%, 77.78%, and 44.44%, respectively) was not significantly different from those of US-guided CNB (88.57%, 2.78%, 87.10%, and 100%, respectively; P ≥ .089). Diagnostic performance did not differ between the modalities according to the size and the location of the lesion in the pancreas. However, the diagnostic yield of US-guided CNB (86.11%) was higher than that of EUS-guided FNA (65.71%, P = .035). The diagnostic yield of US-guided CNB for solid pancreatic lesions is superior to that of EUS-guided FNA. © 2015 by the American Institute of Ultrasound in Medicine.

  17. Fine-needle aspiration of histoplasmosis in the era of endoscopic ultrasound and endobronchial ultrasound: cytomorphologic features and correlation with clinical laboratory testing.

    PubMed

    Gailey, Michael P; Klutts, J Stacey; Jensen, Chris S

    2013-09-01

    Histoplasmosis has a textbook cytologic description with numerous intracellular organisms that are readily apparent on routine stains. This is based on series and reports describing histoplasmosis in immunosuppressed patients with disseminated disease. With the advent of ultrasound-guided (US) fine-needle aspiration (FNA) techniques, a marked increase in the cytologic diagnosis of histoplasmosis in immunocompetent patients is noted. A search identified all cytology cases diagnosed with Histoplasma within the past 10 years. Cases were reviewed, along with patient demographic, clinical, and laboratory data. A total of 40 FNA cases of histoplasmosis were identified. Patients ranged in age from 15 years to 86 years. There were 23 female patients and 17 male patients; 37 were immunocompetent and 3 were immunosuppressed. Sixteen patients were being staged for primary tumors of other sites; others presented with primary pulmonary symptoms or histoplasmosis was noted incidentally. Specimens were composed of bland acellular necrosis, most commonly with granulomas (77.5%); only rare intracellular organisms were present on routine stains, and variable extracellular organisms were noted on Grocott methenamine silver stain (GMS) stain. GMS stain on direct smears was found to be more sensitive than cell block. Laboratory studies for urine antigen, yeast, and mycelial antibody (by compliment fixation), serum antibody (by immunodiffusion), and culture were positive in 11.8%, 59.1%, 4.5%, 47.6%, and 3.4% of cases, respectively. In an endemic region, histoplasmosis presents more commonly in immunocompetent patients as localized fibrocaseous disease on FNA and is often identified by high-resolution imaging. FNA is increasingly used in the diagnosis because of endoscopic ultrasound and endobronchial ultrasound. GMS stain on direct smears is more sensitive than cell block. In general, laboratory tests have low sensitivity in this patient population. Copyright © 2013 American Cancer

  18. Prospective international multicenter study on endoscopic ultrasound-guided biliary drainage for patients with malignant distal biliary obstruction after failed endoscopic retrograde cholangiopancreatography

    PubMed Central

    Khashab, Mouen A.; Van der Merwe, Schalk; Kunda, Rastislav; El Zein, Mohamad H.; Teoh, Anthony Y.; Marson, Fernando P.; Fabbri, Carlo; Tarantino, Ilaria; Varadarajulu, Shyam; Modayil, Rani J.; Stavropoulos, Stavros N.; Peñas, Irene; Ngamruengphong, Saowanee; Kumbhari, Vivek; Romagnuolo, Joseph; Shah, Raj; Kalloo, Anthony N.; Perez-Miranda, Manuel; Artifon, Everson L.

    2016-01-01

    Background and aims: Endoscopic ultrasound-guided biliary drainage (EUS-BD) has emerged as an alternative to traditional radiologic and surgical drainage procedures after failed endoscopic retrograde cholangiopancreatography (ERCP). However, prospective multicenter data are lacking. The aims of this study were to prospectively assess the short- and long-term efficacy and safety of EUS-BD in patients with malignant distal biliary obstruction. Patients and methods: Consecutive patients at 12 tertiary centers (5 US, 5 European, 1 Asian, 1 South American) with malignant distal biliary obstruction and failed ERCP underwent EUS-BD. Technical success was defined as successful stent placement in the desired position. Clinical success was defined as a reduction in bilirubin by 50 % at 2 weeks or to below 3 mg/dL at 4 weeks. Adverse events were prospectively tracked and graded according to the American Society for Gastrointestinal Endoscopy (ASGE) lexicon’s severity grading system. Overall survival and duration of stent patency were calculated using Kaplan–Meier analysis. Results: A total of 96 patients (mean age 66 years, female 45 %, pancreatic cancer 55 %) underwent EUS-BD. Stent placement (technical success) was achieved in 92 (95.8 %) patients (metallic stent 84, plastic stent 8). Mean procedure time was 40 minutes. Clinical success was achieved in 86 (89.5 %) patients. A total of 10 (10.5 %) adverse events occurred: pneumoperitoneum (n = 2), sheared wire (n = 1), bleeding (n = 1), bile leak (n = 3), cholangitis (n = 2), and unintentional perforation (n = 1); 4 graded as mild, 4 moderate, 1 severe, and 1 fatal (due to perforation). A total of 38 (44 %) patients died of disease progression during the study period. The median patient survival was 167 days (95 %CI 112 – 221) days. The 6-month stent patency rate was 95 % (95 %CI 94.94 – 95.06 %) and the 1-year stent patency was 86 % (95 %CI 85.74 – 86

  19. Endoscopic ultrasound-guided hepaticogastrostomy versus percutaneous transhepatic drainage for malignant biliary obstruction after failed endoscopic retrograde cholangiopancreatography: a retrospective expertise-based study from two centers

    PubMed Central

    Sportes, Adrien; Camus, Marine; Greget, Michel; Leblanc, Sarah; Coriat, Romain; Hochberger, Jürgen; Chaussade, Stanislas; Grabar, Sophie; Prat, Frédéric

    2017-01-01

    Background: Percutaneous transhepatic biliary drainage (PTBD) is widely performed as a salvage procedure in patients with unresectable malignant obstruction of the common bile duct (CBD) after failed endoscopic retrograde cholangiopancreatography (ERCP) or in case of surgically altered anatomy. Endoscopic ultrasound-guided hepaticogastrostomy (EU-HGS) is a more recently introduced alternative to relieve malignant obstructive jaundice. The aim of this prospective observational study was to compare the outcome, efficacy and adverse events of EU-HGS and PTBD. Methods: From April 2012 to August 2015, consecutive patients with malignant CBD obstruction who underwent EU-HGS or PTBD in two tertiary-care referral centers were included. The primary endpoint was the clinical success rate. Secondary endpoints were technical success, overall survival, procedure-related adverse events, incidence of adverse events, and reintervention rate. Results: A total of 51 patients (EU-HGS, n = 31; PTBD, n = 20) were included. Median survival was 71 days (range 25–75th percentile; 30–95) for the EU-HGS group and 78 days (range 25–75th percentile; 42–108) for the PTBD group (p = 0.99). Technical success was achieved in all patients in both groups. Clinical success was achieved in 25 (86%) of 31 patients in the EU-HGS group and in 15 (83%) of 20 patients in the PTBD group (p = 0.88). There was no difference in adverse events rates between the two groups (EU-HGS: 16%; PTBD: 10%) (p = 0.69). Four deaths within 1 month (two hemorrhagic and two septic) were considered procedure related (two in the EU-HGS group and two in the PTBD group). Overall reintervention rate was significantly lower after EU-HGS (n = 2) than after PTBD (n = 21) (p = 0.0001). Length of hospital stay was shorter after EU-HGS (8 days versus 15 days; p = 0.002). Conclusions: EU-HGS can be an effective and safe mini invasive-procedure alternative to PTBD, with similar success and adverse-event rates, but with lower

  20. Maximizing the endosonography: The role of contrast harmonics, elastography and confocal endomicroscopy

    PubMed Central

    Seicean, Andrada; Mosteanu, Ofelia; Seicean, Radu

    2017-01-01

    New technologies in endoscopic ultrasound (EUS) evaluation have been developed because of the need to improve the EUS and EUS-fine needle aspiration (EUS-FNA) diagnostic rate. This paper reviews the principle, indications, main literature results, limitations and future expectations for each of the methods presented. Contrast-enhanced harmonic EUS uses a low mechanical index and highlights slow-flow vascularization. This technique is useful for differentiating solid and cystic pancreatic lesions and assessing biliary neoplasms, submucosal neoplasms and lymph nodes. It is also useful for the discrimination of pancreatic masses based on their qualitative patterns; however, the quantitative assessment needs to be improved. The detection of small solid lesions is better, and the EUS-FNA guidance needs further research. The differentiation of cystic lesions of the pancreas and the identification of the associated malignancy features represent the main indications. Elastography is used to assess tissue hardness based on the measurement of elasticity. Despite its low negative predictive value, elastography might rule out the diagnosis of malignancy for pancreatic masses. Needle confocal laser endomicroscopy offers useful information about cystic lesions of the pancreas and is still under evaluation for use with solid pancreatic lesions of lymph nodes. PMID:28104978

  1. Randomized controlled study of the safety and efficacy of nitrous oxide-sedated endoscopic ultrasound-guided fine needle aspiration for digestive tract diseases

    PubMed Central

    Wang, Cai-Xia; Wang, Jian; Chen, Yuan-Yuan; Wang, Jia-Ni; Yu, Xin; Yang, Feng; Sun, Si-Yu

    2016-01-01

    AIM To evaluate the efficacy and safety of nitrous oxide-sedated endoscopic ultrasound-guided fine needle aspiration. METHODS Enrolled patients were divided randomly into an experimental group (inhalation of nitrous oxide) and a control group (inhalation of pure oxygen) and heart rate, blood oxygen saturation, blood pressure, electrocardiogram (ECG) changes, and the occurrence of complications were monitored and recorded. All patients and physicians completed satisfaction questionnaires about the examination and scored the process using a visual analog scale. RESULTS There was no significant difference in heart rate, blood oxygen saturation, blood pressure, ECG changes, or complication rate between the two groups of patients (P > 0.05). However, patient and physician satisfaction were both significantly higher in the nitrous oxide compared with the control group (P < 0.05). CONCLUSION Nitrous oxide-sedation is a safe and effective option for patients undergoing endoscopic ultrasound-guided fine needle aspiration. PMID:28028373

  2. Shear wave elastography with a new reliability indicator.

    PubMed

    Dietrich, Christoph F; Dong, Yi

    2016-09-01

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

  3. Sensitivity of endoscopic ultrasound, multidetector computed tomography, and magnetic resonance cholangiopancreatography in the diagnosis of pancreas divisum: a tertiary center experience.

    PubMed

    Kushnir, Vladimir M; Wani, Sachin B; Fowler, Kathryn; Menias, Christine; Varma, Rakesh; Narra, Vamsi; Hovis, Christine; Murad, Faris M; Mullady, Daniel K; Jonnalagadda, Sreenivasa S; Early, Dayna S; Edmundowicz, Steven A; Azar, Riad R

    2013-04-01

    There are limited data comparing imaging modalities in the diagnosis of pancreas divisum. We aimed to: (1) evaluate the sensitivity of endoscopic ultrasound (EUS), magnetic resonance cholangiopancreatography (MRCP), and multidetector computed tomography (MDCT) for pancreas divisum; and (2) assess interobserver agreement (IOA) among expert radiologists for detecting pancreas divisum on MDCT and MRCP. For this retrospective cohort study, we identified 45 consecutive patients with pancreaticobiliary symptoms and pancreas divisum established by endoscopic retrograde pancreatography who underwent EUS and cross-sectional imaging. The control group was composed of patients without pancreas divisum who underwent endoscopic retrograde pancreatography and cross-sectional imaging. The sensitivity of EUS for pancreas divisum was 86.7%, significantly higher than the sensitivity reported in the medical records for MDCT (15.5%) or MRCP (60%) (P < 0.001 for each). On review by expert radiologists, the sensitivity of MDCT increased to 83.3% in cases where the pancreatic duct was visualized, with fair IOA (κ = 0.34). Expert review of MRCPs did not identify any additional cases of pancreas divisum; IOA was moderate (κ = 0.43). Endoscopic ultrasound is a sensitive test for diagnosing pancreas divisum and is superior to MDCT and MRCP. Review of MDCT studies by expert radiologists substantially raises its sensitivity for pancreas divisum.

  4. ANTHROPOMORPHIC BREAST PHANTOMS FOR TESTING ELASTOGRAPHY SYSTEMS

    PubMed Central

    Madsen, Ernest L.; Hobson, Maritza A.; Frank, Gary R.; Shi, Hairong; Jiang, Jingfeng; Hall, Timothy J.; Varghese, Tomy; Doyley, Marvin M.; Weaver, John B.

    2006-01-01

    Two equivalent anthropomorphic breast phantoms were constructed, one for use in ultrasound elastography and the other in magnetic resonance (MR) elastography. A complete description of the manufacturing methods is provided. The materials used were oil-in-gelatin dispersions, where the volume percent oil differentiates the materials, primarily according to Young’s moduli. Values of Young’s moduli are in agreement with in vitro ranges for the corresponding normal and abnormal breast tissues. Ultrasound and nuclear magnetic resonance (NMR) properties are reasonably well represented. Phantoms of the type described promise to aid researchers who are developing hardware and software for elastography. Examples of ultrasound and MR elastograms of the phantoms are included to demonstrate the utility of the phantoms. Also, the level of stability of elastic properties of the component materials is quantified over a 15-month period. Such phantoms can serve as performance-assessing intermediaries between simple phantoms (consisting, for example, of homogeneous cylindrical inclusions in a homogeneous background) and a full-scale clinical trial. Thus, premature clinical trials may be avoided. PMID:16785008

  5. [Frequency of visualization of celiac ganglia by endoscopic ultrasound and its potential in assessing neural invasion in patients with pancreatic lesions].

    PubMed

    Peláez-Luna, M; Borbolla-Arizti, J P; Herrera-Lozano, A; Baquera-Heredia, J

    2013-01-01

    Celiac ganglia (CG) can be seen by endoscopic ultrasound; they play an important role in pain management and are a potential site for extrapancreatic tumor neural invasion. To evaluate the frequency of CG visualization during endoscopic ultrasound examination and to evaluate the feasibility of this technique to identify extrapancreatic tumor neural invasion in patients with pancreatic lesions. We retrospectively reviewed all endoscopic ultrasound studies performed between November 2007 and June 2010. Images of the celiac region were presented to an endosonographer, who reported the presence or absence of CG. We included 31 cases. CG were identified in 14 (45%) cases. Average size was 10mm (range 4-25mm) by±1mm (range 1-7mm). In 2 cases, fine needle aspiration biopsy was performed and reported nerve cell bodies; in one case malignant cells were seen. CG were identified in 45% of the cases. Fine needle aspiration biopsy can detect unanticipated extrapancreatic tumor neural invasion in pancreatic malignancies. Copyright © 2013 Asociación Mexicana de Gastroenterología. Published by Masson Doyma México S.A. All rights reserved.

  6. Cost-Effectiveness Analysis of Endoscopic Ultrasound versus Magnetic Resonance Cholangiopancreatography in Patients with Suspected Common Bile Duct Stones

    PubMed Central

    Morris, Stephen; Gurusamy, Kurinchi S.; Sheringham, Jessica; Davidson, Brian R.

    2015-01-01

    Background Patients with suspected common bile duct (CBD) stones are often diagnosed using endoscopic retrograde cholangiopancreatography (ERCP), an invasive procedure with risk of significant complications. Using endoscopic ultrasound (EUS) or Magnetic Resonance CholangioPancreatography (MRCP) first to detect CBD stones can reduce the risk of unnecessary procedures, cut complications and may save costs. Aim This study sought to compare the cost-effectiveness of initial EUS or MRCP in patients with suspected CBD stones. Methods This study is a model based cost-utility analysis estimating mean costs and quality-adjusted life years (QALYs) per patient from the perspective of the UK National Health Service (NHS) over a 1 year time horizon. A decision tree model was constructed and populated with probabilities, outcomes and cost data from published sources, including one-way and probabilistic sensitivity analyses. Results Using MRCP to select patients for ERCP was less costly than using EUS to select patients or proceeding directly to ERCP ($1299 versus $1753 and $1781, respectively), with similar QALYs accruing to each option (0.998, 0.998 and 0.997 for EUS, MRCP and direct ERCP, respectively). Initial MRCP was the most cost-effective option with the highest monetary net benefit, and this result was not sensitive to model parameters. MRCP had a 61% probability of being cost-effective at $29,000, the maximum willingness to pay for a QALY commonly used in the UK. Conclusion From the perspective of the UK NHS, MRCP was the most cost-effective test in the diagnosis of CBD stones. PMID:25799113

  7. A comparison between endoscopic ultrasound-guided rendezvous and percutaneous biliary drainage after failed ERCP for malignant distal biliary obstruction

    PubMed Central

    Bill, Jason G.; Darcy, Michael; Fujii-Lau, Larissa L.; Mullady, Daniel K.; Gaddam, Srinivas; Murad, Faris M.; Early, Dayna S.; Edmundowicz, Steven A.; Kushnir, Vladimir M.

    2016-01-01

    Background and study Aims: Selective biliary cannulation is unsuccessful in 5 % to 10 % of patients undergoing endoscopic retrograde cholangiopancreatography (ERCP) for malignant distal biliary obstruction (MDBO). Percutaneous biliary drainage (PBD) has been the gold standard, but endoscopic ultrasound guided rendezvous (EUSr) have been increasingly used for biliary decompression in this patient population. Our aim was to compare the initial success rate, long-term efficacy, and safety of PBD and EUSr in relieving MDBO after failed ERC Patients and methods: A retrospective study involving 50 consecutive patients who had an initial failed ERCP for MDBO. Twenty-five patients undergoing EUSr between 2008 – 2014 were compared to 25 patients who underwent PBD immediately prior to the introduction of EUSr at our center (2002 – 2008). Comparisons were made between the two groups with regard to technical success, duration of hospital stay and adverse event rates after biliary decompression. Results: The mean age at presentation was 66.5 (± 12.6 years), 28 patients (54.9 %) were female. The etiology of MDBO was pancreaticobiliary malignancy in 44 (88 %) and metastatic disease in 6 (12 %) cases. Biliary drainage was technically successful by EUSr in 19 (76 %) cases and by PBD in 25 (100 %) (P = 0.002). Median length of hospital stay after initial drainage was 1 day in the EUSr group vs 5 days in PBD group (P = 0.02). Repeat biliary intervention was required for 4 patients in the EUSr group and 15 in the PBD group (P = 0.001). Conclusions: Initial technical success with EUSr was significantly lower than with PBD, however when EUSr was successful, patients had a significantly shorter post-procedure hospital stay and required fewer follow-up biliary interventions. Meeting presentations: Annual Digestive Diseases Week 2015 PMID:27652305

  8. Gangliocytic paraganglioma, a rare cause of upper gastrointestinal bleeding: Endoscopic ultrasound findings presented

    SciTech Connect

    Smithline, A.E.; Hawes, R.H.; Kopecky, K.K.; Cummings, O.W.; Kumar, S. )

    1993-01-01

    Gangliocytic paraganglioma (GP) is an uncommon benign neurogenic tumor of the digestive tract that is usually located in the descending duodenum. Patients with GP usually present with upper gastrointestinal hemorrhage, which reflects the tendency of the tumor to ulcerate the mucosa. The authors report a patient in whom the tumor was overlooked on routine radiologic examinations and initial endoscopy. It was discovered in the distal transverse duodenum at small bowel enteroscopy. The findings of endoscopic ultrasonography are correlated with radiographic and histologic examination. 10 refs.

  9. Elastography in Chronic Liver Disease: Modalities, Techniques, Limitations, and Future Directions.

    PubMed

    Srinivasa Babu, Aparna; Wells, Michael L; Teytelboym, Oleg M; Mackey, Justin E; Miller, Frank H; Yeh, Benjamin M; Ehman, Richard L; Venkatesh, Sudhakar K

    2016-01-01

    Chronic liver disease has multiple causes, many of which are increasing in prevalence. The final common pathway of chronic liver disease is tissue destruction and attempted regeneration, a pathway that triggers fibrosis and eventual cirrhosis. Assessment of fibrosis is important not only for diagnosis but also for management, prognostic evaluation, and follow-up of patients with chronic liver disease. Although liver biopsy has traditionally been considered the reference standard for assessment of liver fibrosis, noninvasive techniques are the emerging focus in this field. Ultrasound-based elastography and magnetic resonance (MR) elastography are gaining popularity as the modalities of choice for quantifying hepatic fibrosis. These techniques have been proven superior to conventional cross-sectional imaging for evaluation of fibrosis, especially in the precirrhotic stages. Moreover, elastography has added utility in the follow-up of previously diagnosed fibrosis, the assessment of treatment response, evaluation for the presence of portal hypertension (spleen elastography), and evaluation of patients with unexplained portal hypertension. In this article, a brief overview is provided of chronic liver disease and the tools used for its diagnosis. Ultrasound-based elastography and MR elastography are explored in depth, including a brief glimpse into the evolution of elastography. Elastography is based on the principle of measuring tissue response to a known mechanical stimulus. Specific elastographic techniques used to exploit this principle include MR elastography and ultrasonography-based static or quasistatic strain imaging, one-dimensional transient elastography, point shear-wave elastography, and supersonic shear-wave elastography. The advantages, limitations, and pitfalls of each modality are emphasized. (©)RSNA, 2016.

  10. Endoscopic Ultrasound-Guided Fine Needle Aspiration versus Percutaneous Ultrasound-Guided Fine Needle Aspiration in Diagnosis of Focal Pancreatic Masses.

    PubMed

    Okasha, Hussein Hassan; Naga, Mazen Ibrahim; Esmat, Serag; Naguib, Mohamed; Hassanein, Mohamed; Hassani, Mohamed; El-Kassas, Mohamed; Mahdy, Reem Ezzat; El-Gemeie, Emad; Farag, Ali Hassan; Foda, Ayman Mohamed

    2013-10-01

    Pancreatic carcinoma is one of the leading cancer morbidity and mortality world-wide. Controversy has arisen about whether the percutaneous approach with computed tomography/ultrasonography-guidance fine needle aspiration (US-FNA) or endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is the preferred method to obtain diagnostic tissue. Our purpose of this study is to compare between the diagnostic accuracy of EUS-FNA and percutaneous US-FNA in diagnosis of pancreatic cancer. A total of 197 patients with pancreatic masses were included in the study, 125 patients underwent US-FNA (Group 1) and 72 patients underwent EUS-FNA (Group 2). EUS-FNA has nearly the same accuracy (88.9%) as US-FNA (87.2%) in diagnosis of pancreatic cancer. The sensitivity, specificity, positive predictive value and negative predictive value for EUS-FNA was 84%, 100%, 100%, 73.3% respectively. It was 85.5%, 90.4%, 94.7%, 76% respectively for US-FNA. EUS-FNA had a lower complication rate (1.38%) than US-FNA (5.6%). EUS-FNA has nearly the same accuracy as US-FNA of pancreatic masses with a lower complication rate.

  11. Endoscopic Ultrasound-Guided Fine Needle Aspiration versus Percutaneous Ultrasound-Guided Fine Needle Aspiration in Diagnosis of Focal Pancreatic Masses

    PubMed Central

    Okasha, Hussein Hassan; Naga, Mazen Ibrahim; Esmat, Serag; Naguib, Mohamed; Hassanein, Mohamed; Hassani, Mohamed; El-Kassas, Mohamed; Mahdy, Reem Ezzat; El-Gemeie, Emad; Farag, Ali Hassan; Foda, Ayman Mohamed

    2013-01-01

    Objective: Pancreatic carcinoma is one of the leading cancer morbidity and mortality world-wide. Controversy has arisen about whether the percutaneous approach with computed tomography/ultrasonography-guidance fine needle aspiration (US-FNA) or endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is the preferred method to obtain diagnostic tissue. Our purpose of this study is to compare between the diagnostic accuracy of EUS-FNA and percutaneous US-FNA in diagnosis of pancreatic cancer. Patients and Methods: A total of 197 patients with pancreatic masses were included in the study, 125 patients underwent US-FNA (Group 1) and 72 patients underwent EUS-FNA (Group 2). Results: EUS-FNA has nearly the same accuracy (88.9%) as US-FNA (87.2%) in diagnosis of pancreatic cancer. The sensitivity, specificity, positive predictive value and negative predictive value for EUS-FNA was 84%, 100%, 100%, 73.3% respectively. It was 85.5%, 90.4%, 94.7%, 76% respectively for US-FNA. EUS-FNA had a lower complication rate (1.38%) than US-FNA (5.6%). Conclusion: EUS-FNA has nearly the same accuracy as US-FNA of pancreatic masses with a lower complication rate. PMID:24949394

  12. Harmonic contrast-enhanced endoscopic ultrasound fine-needle aspiration: Fact or fiction?

    PubMed

    Seicean, Andrada; Jinga, Mariana

    2017-01-01

    The negative predictive value of endoscopic ultrasonography fine-needle aspiration is relatively low. To achieve the improvement of the diagnostic yield, the following were proposed: a higher number of passes, the presence of the rapid on-site cytopathologist evaluation, the fanning technique, or the repetition of the fine needle biopsy. Harmonic contrast-enhanced endosonography may better identify the targeted area in the lesions by avoiding the inside necrosis and the vessels of fibrosis, so it can guide the fine-needle aspiration. Both techniques are complementary, not competitive, and they can be done in the same session. The combined technique is simple, safe, and requires only a few minutes with minimal extra costs compared to standard fine-needle aspiration. It minimally increases the diagnostic rate, and it permits the decrease of the number of passes. However, we will know its real clinical impact only in the future and whether it will be incorporated into the lesion assessment process.

  13. Endoscopic Ultrasound Guided Rendezvous Drainage of Biliary Obstruction Using a New Flexible 19-Gauge Fine Needle Aspiration Needle

    PubMed Central

    Tang, Zhouwen; Igbinomwanhia, Efehi; Elhanafi, Sherif

    2016-01-01

    Background and Aim. A successful endoscopic ultrasound guided rendezvous (EUS-RV) biliary drainage is dependent on accurate puncture of the bile duct and precise guide wire manipulation across the ampulla of Vater. We aim to study the feasibility of using a flexible 19-gauge fine aspiration needle in the performance of EUS-RV biliary drainage. Method. This is a retrospective case series of EUS-RV biliary drainage procedures at a single center. Patients who failed ERCP during the same session for benign or malignant biliary obstruction underwent EUS-RV using a flexible, nitinol covered, 19-gauge needle for biliary access and guide wire manipulation. Result. 24 patients underwent EUS-RV biliary drainage via extrahepatic access while 1 attempt was via intrahepatic access. The technical success rate was 80%, including 83.3% of cases via extrahepatic access. There was no significant difference in success rate of inpatient and outpatient procedures, benign or malignant indications, or type of guide wire used. Adverse events included mild pancreatitis (3 patients) and cholangitis (1 patient). Conclusion. A flexible 19-gauge needle for biliary access can be safe and effective when used to perform EUS-RV biliary drainage. Direct comparison between the nitinol needle and conventional metal needles in the performance of EUS guided biliary drainage is needed. PMID:27822005

  14. Eosinophilic esophageal myositis diagnosed by endoscopic ultrasound-guided fine-needle aspiration biopsy: a case report.

    PubMed

    Igarashi, Ryo; Irisawa, Atsushi; Shibukawa, Goro; Yamabe, Akane; Fujisawa, Mariko; Sato, Ai; Maki, Takumi; Arakawa, Noriyuki; Yoshida, Yoshitsugu; Yamamoto, Shogo; Ikeda, Tsunehiko

    2016-10-01

    Eosinophilic esophagitis (EoE) is diagnosed by microscopic findings of eosinophilic infiltration into the squamous epithelium. In contrast, another disease concept termed "eosinophilic esophageal myositis (EoEM)" has been proposed, whereby there is eosinophilic infiltration into the muscularis propria instead. A 60-year-old man was referred to our hospital for chest pain, dysphagia, and several episodes of esophageal food impaction. Although EoE was suspected based on clinical features, biopsy specimens showed no mucosal eosinophilic infiltration. Endoscopic ultrasound (EUS) showed thickening of the muscularis propria layer and subsequent EUS-guided fine-needle aspiration biopsy (EUS-FNA) revealed eosinophilic infiltration into the muscularis propria. Although the patient's symptoms gradually improved after steroid administration, complete remission was not achieved after 1 year of treatment. This case may reflect a disorder distinct from typical EoE based on eosinophilic infiltration of the muscularis propria but not the squamous epithelium, and we, therefore, diagnosed it as EoEM using the EUS-FNA findings as reference.

  15. Endoscopic ultrasound-guided fine-needle aspiration diagnosis of Merkel cell carcinoma metastatic to the pancreas.

    PubMed

    Bernstein, Jane; Adeniran, Adebowale J; Cai, Guoping; Theoharis, Constantine G A; Ustun, Berrin; Beckman, Danita; Aslanian, Harry R; Harigopal, Malini

    2014-03-01

    Merkel cell carcinoma (MCC) is a rare and highly aggressive primary neuroendocrine carcinoma of the skin with a high propensity for local, regional, and distant spread. Distant metastasis of MCC to the pancreas is uncommonly seen and may impose a diagnostic challenge cytologically. Here we report a case of MCC with pancreatic metastasis, which was diagnosed by endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA). The aspirates revealed both single and clustered epithelial cells with scant cytoplasm and round nuclei with stippled chromatin and inconspicuous nucleoli. Immunocytochemically, the tumor cells were positive for CK20, synaptophysin, CD56, and CD117. The neoplastic cells were also identified by flow cytometry as non-hematopoietic cells which were positive for CD56 and negative for CD45. To our knowledge, this is only the second case report of MCC metastatic to the pancreas diagnosed by EUS-FNA. There have been several reports of MCC metastatic to the pancreas diagnosed only at the time of surgical resection. However, a preoperative diagnosis allows for appropriate management while sparing a patient the morbidity of unnecessary procedures.

  16. Diagnosis of pancreatic lesions collected by endoscopic ultrasound-guided fine-needle aspiration using next-generation sequencing

    PubMed Central

    Kameta, Eri; Sugimori, Kazuya; Kaneko, Takashi; Ishii, Tomohiro; Miwa, Haruo; Sato, Takeshi; Ishii, Yasuaki; Sue, Soichiro; Sasaki, Tomohiko; Yamashita, Yuki; Shibata, Wataru; Matsumoto, Naomichi; Maeda, Shin

    2016-01-01

    Endoscopic ultrasound-guided fine-needle aspiration (EUF-FNA) has improved the diagnosis of pancreatic lesions. Next-generation sequencing (NGS) facilitates the production of millions of sequences concurrently. Therefore, in the current study, to improve the detectability of oncogenic mutations in pancreatic lesions, an NGS system was used to diagnose EUS-FNA samples. A total of 38 patients with clinically diagnosed EUS-FNA specimens were analyzed; 27 patients had pancreatic ductal adenocarcinoma (PDAC) and 11 had non-PDAC lesions. DNA samples were isolated and sequenced by NGS using an Ion Personal Genome Machine system. The Cancer Hotspot Panel v2, which includes 50 cancer-related genes and 2,790 COSMIC mutations, was used. A >2% mutation frequency was defined as positive. KRAS mutations were detected in 26 of 27 PDAC aspirates (96%) and 0 of 11 non-PDAC lesions (0%). The G12, G13, and Q61 KRAS mutations were found in 25, 0, and 1 of the 27 PDAC samples, respectively. Mutations were confirmed by TaqMan® polymerase chain reaction analysis. TP53 mutations were detected in 12 of 27 PDAC aspirates (44%). SMAD4 was observed in 3 PDAC lesions and cyclin-dependent kinase inhibitor 2A in 4 PDAC lesions. Therefore, the current study was successfully able to develop an NGS assay with high clinical sensitivity for EUS-FNA samples. PMID:27895743

  17. Differential diagnosis between pancreatic neuroendocrine and solid pseudopapillary neoplasms on endoscopic ultrasound-guided fine-needle aspiration

    PubMed Central

    Raddaoui, Emad M.; Almadi, Majid A.; Aljebreen, Abdulrahman M.; Alsaif, Faisal A.; AlShedoukhy, Ahlam A.; Al-Lehibi, Abed H.; Almohameed, Khalid A.; Tsolakis, Apostolos V.; AlAbbadi, Mousa A.; Almutrafi, Amna R.

    2016-01-01

    Objectives: To evaluate the role of applying a limited panel of immunohistochemical stains on the cellblock preparation from samples obtained by endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) in the aim of differentiating solid pseudopapillary neoplasms (SPNs) from neuroendocrine tumors (NETs). Methods: We retrospectively retrieved all the EUS-FNAs of the pancreas that have a diagnosis of NET or SPN that were performed at 2 tertiary care hospitals in Riyadh, Kingdom of Saudi Arabia from May 2004 to December 2014. Diff-Quik, Papanicolaou, and Immunohistochemistry stains on cellblock preparations were performed. Results: Twenty cases were available (16 pancreatic neuroendocrine tumors (pNETs) and 4 SPNs). The pNETs were immunoreactive for synaptophysin, chromogranin A and CD56 while E-cadherin was diffusely to focally cytoplasmic positive. β-catenin was negative or showed focal cytoplasmic immunoreactivity. In comparison, SPNs were positive for vimentin, CD10, CD-56, focally positive for progesterone receptors and synaptophysin, and revealed nuclear immunostaining for β-catenin. They were negative for chromogranin A and E-cadherin. Conclusion: Based on EUS-FNA samples, nuclear immunoreactivity for β-catenin with loss of membranous immunostaining for E-Cadherin can potentially facilitate differentiating SPNs from pNETs. PMID:27381533

  18. Diagnosis of primary squamous cell carcinoma of the pancreas using endoscopic ultrasound-guided core needle biopsy.

    PubMed

    Kashani, Amir; Kahn, Melissa; Jamil, Laith H

    2015-05-16

    Primary squamous cell carcinoma (SCC) of the pancreas is a particularly rare entity. Diagnosis of this tumor is tentatively made after ruling out metastatic SCC from another primary site and adenosquamous carcinoma (ASC) of the pancreas. Here we discuss the case of a 76-year-old woman who was found to have a solitary pancreatic lesion and multiple hepatic lesions. Results of computed tomography-guided biopsy of the liver lesions were consistent with a metastatic carcinoma displaying squamous differentiation; therefore, an endoscopic ultrasound (EUS)-guided core-needle biopsy (CNB) of the pancreatic mass was performed. Meticulous histopathological examination of the pancreatic specimen at multiple levels revealed moderately well-differentiated SCC with no glandular component. An extensive metastatic work-up did not reveal an extra-pancreatic origin for this SCC; hence, a diagnosis of primary SCC of the pancreas was established. To our knowledge, this is the first report of the diagnosis of a primary SCC of the pancreas using EUS-guided CNB. We believe that CNB has a diagnostic yield equivalent to that of fine-needle aspiration for recognizing pancreatic adenocarcinoma; however, when cytological examinations reveal atypical squamous epithelial cells suggestive of malignancy, CNB may provide a better tissue specimen, from which to determine the presence of a glandular component. Such an assessment will differentiate pancreatic SCC from ASC.

  19. A comparison of endoscopic ultrasound, magnetic resonance imaging, and exam under anesthesia for evaluation of Crohn's perianal fistulas.

    PubMed

    Schwartz, D A; Wiersema, M J; Dudiak, K M; Fletcher, J G; Clain, J E; Tremaine, W J; Zinsmeister, A R; Norton, I D; Boardman, L A; Devine, R M; Wolff, B G; Young-Fadok, T M; Diehl, N N; Pemberton, J H; Sandborn, W J

    2001-11-01

    To determine accuracy of endoscopic ultrasound (EUS) and magnetic resonance imaging (MRI) for evaluation of Crohn's disease perianal fistulas. Thirty-four patients with suspected Crohn's disease perianal fistulas were prospectively enrolled in a blinded study comparing EUS, MRI, and examination under anesthesia (EUA). Fistulas were classified according to Parks' criteria, and a consensus gold standard was determined for each patient. Acceptable accuracy was defined as agreement with the consensus gold standard for > or =85% of patients. Three patients did not undergo MRI; 1 did not undergo EUS or EUA; and consensus could not be reached for 1. Thirty-two patients had 39 fistulas (20 trans-sphincteric, 5 extra-sphincteric, 6 recto-vaginal, 8 others) and 13 abscesses. The accuracy of all 3 modalities was > or =85%: EUS 29 of 32 (91%, confidence interval [CI] 75%-98%), MRI 26 of 30 (87%, CI 69%-96%), and EUA 29 of 32 (91%, CI 75%-98%). Accuracy was 100% when any 2 tests were combined. EUS, MRI, and EUA are accurate tests for determining fistula anatomy in patients with perianal Crohn's disease. The optimal approach may be combining any 2 of the 3 methods.

  20. Predictors for Surgical Referral in Patients With Pancreatic Cystic Lesions Undergoing Endoscopic Ultrasound: Results From a Large Multicenter Cohort Study.

    PubMed

    Ge, Phillip S; Gaddam, Srinivas; Keach, Joseph W; Mullady, Daniel; Fukami, Norio; Edmundowicz, Steven A; Azar, Riad R; Shah, Raj J; Murad, Faris M; Kushnir, Vladimir M; Ghassemi, Kourosh F; Sedarat, Alireza; Watson, Rabindra R; Amateau, Stuart K; Brauer, Brian C; Yen, Roy D; Hosford, Lindsay; Hollander, Thomas; Donahue, Timothy R; Schulick, Richard D; Edil, Barish H; McCarter, Martin D; Gajdos, Csaba; Attwell, Augustin R; Muthusamy, V Raman; Early, Dayna S; Wani, Sachin

    2016-01-01

    Endoscopic ultrasound (EUS) plays an integral role in the evaluation of pancreatic cysts lesions (PCLs). The aim of the study was to determine predictors of surgical referral in patients with PCLs undergoing EUS. We performed a multicenter retrospective study of patients undergoing EUS for evaluation of PCLs. Demographics, EUS characteristics, and fine-needle aspiration results were recorded. Patients were categorized into surgery or surveillance groups on the basis of post-EUS recommendations. Univariate and multivariate analyses were performed to identify predictors of surgical referral. 1804 patients were included. 1301 patients were recommended to undergo surveillance and 503 patients were referred for surgical evaluation, of which 360 patients underwent surgery. Multivariate analysis revealed the following 5 independent predictors of surgical referral: symptoms of weight loss on presentation (odds ratio [OR], 2.69; 95% confidence interval [CI], 1.44-5.03), EUS findings of associated solid mass (OR, 7.34; 95% CI, 3.81-14.16), main duct communication (OR, 4.13; 95% CI, 1.71-9.98), multilocular macrocystic morphology (OR, 2.79; 95% CI, 1.78-4.38), and fine-needle aspiration findings of mucin on cytology (OR, 3.06; 95% CI, 1.94-4.82). This study identifies factors associated with surgical referral in patients with PCLs undergoing EUS. Future studies should focus on creation of risk stratification models to determine the need for surgery or enrollment in surveillance programs.

  1. Endoscopic ultrasound as an adjunctive evaluation in patients with esophageal motor disorders subtyped by high-resolution manometry

    PubMed Central

    Krishnan, Kumar; Lin, Chen-Yuan; Keswani, Rajesh; Pandolfino, John E; Kahrilas, Peter J; Komanduri, Srinadh

    2015-01-01

    Background and aims Esophageal motor disorders are a heterogenous group of conditions identified by esophageal manometry that lead to esophageal dysfunction. The aim of this study was to assess the clinical utility of endoscopic ultrasound in the further evaluation of patients with esophageal motor disorders categorized using the updated Chicago Classification. Methods We performed a retrospective, single center study of 62 patients with esophageal motor disorders categorized according to the Chicago Classification. All patients underwent standard radial endosonography to assess for extra esophageal findings or alternative explanations for esophageal outflow obstruction. Secondary outcomes included esophageal wall thickness among the different patient subsets within the Chicago Classification Key Results EUS identified 9/62 (15%) clinically relevant findings that altered patient management and explained the etiology of esophageal outflow obstruction. We further identified substantial variability in esophageal wall thickness in a proportion of patients including some with a significantly thickened non-muscular layer. Conclusions EUS findings are clinically relevant in a significant number of patients with motor disorders and can alter clinical management. Variability in esophageal wall thickness of the muscularis propria and non-muscular layers identified by EUS may also explain the observed variability in response to standard therapies for achalasia. PMID:25041229

  2. Usefulness of strain elastography of the musculoskeletal system

    PubMed Central

    2016-01-01

    Ultrasound elastography is a widely used technique for assessing the mechanical characteristics of tissues. Although there are several ultrasound elastography techniques, strain elastography (SE) is currently the most widely used technique for visualizing an elastographic map in real time. Among its various indications, SE is especially useful in evaluating the musculoskeletal system. In this article, we review the SE techniques for clinical practice and describe the images produced by these techniques in the context of the musculoskeletal system. SE provides information about tissue stiffness and allows real-time visualization of the image; however, SE cannot completely replace gray-scale, color, or power Doppler ultrasonography. SE can increase diagnostic accuracy and may be useful for the follow-up of benign lesions. PMID:26810195

  3. Ultrasound

    MedlinePlus

    Ultrasound is a type of imaging. It uses high-frequency sound waves to look at organs and ... liver, and other organs. During pregnancy, doctors use ultrasound to view the fetus. Unlike x-rays, ultrasound ...

  4. The impact of endoscopic ultrasound findings on clinical decision making in Barrett's esophagus with high-grade dysplasia or early esophageal adenocarcinoma.

    PubMed

    Bulsiewicz, W J; Dellon, E S; Rogers, A J; Pasricha, S; Madanick, R D; Grimm, I S; Shaheen, N J

    2014-07-01

    The clinical utility of endoscopic ultrasound (EUS) for staging patients with Barrett's esophagus and high-grade dysplasia (HGD) or intramucosal carcinoma (IMC) prior to endoscopic therapy is unclear. We performed a retrospective analysis of patients with HGD or IMC referred to an American medical center for endoscopic treatment between 2004 and 2010. All patients had pretreatment staging by EUS. We examined the frequency that EUS findings consistent with advanced disease (tumor invasion into the submucosa, lymph node involvement, or regional metastasis) led to a change in management. The analysis was stratified by nodularity and pre-EUS histology. We identified one hundred thirty-five patients with HGD (n = 106, 79%) or IMC (n = 29, 21%) had staging by EUS (79 non-nodular, 56 nodular). Pathologic lymph nodes or metastases were not found by EUS. There were no endosonographic abnormalities noted in any patient with non-nodular mucosa (0/79). Abnormal EUS findings were present in 8/56 patients (14%) with nodular neoplasia (five IMC, three HGD). Endoscopic mucosal resection was performed in 44 patients with a nodule, with 13% (6/44) having invasive cancer. In nodular neoplasia, the EUS and endoscopic mucosal resection were abnormal in 24% (5/21) and 40% (6/15) of those with IMC and 9% (3/35) and 0% (0/29) of those with HGD, respectively. In this study we found that EUS did not alter management in patients with non-nodular HGD or IMC. Because the diagnostic utility of EUS in subjects with non-nodular Barrett's esophagus is low, the value of performing endoscopic mucosal resection in this setting is questionable. For patients with nodular neoplasia, resection of the nodule with histological examination had greater utility than staging by EUS.

  5. Endoscopic ultrasound versus multidetector computed tomography in preoperative gastric cancer staging.

    PubMed

    Cimavilla Román, Marta; de la Serna Higuera, Carlos; Loza Vargas, Luz Andrea; Benito Fernández, César; Barrio Andrés, Jesús; Madrigal Rubiales, Beatriz; Fernández Pérez, Gabriel; Pérez-Miranda, Manuel

    2017-09-25

    Endoscopic ultrasonography (EUS) is the gold standard technique in loco-regional staging of gastric adenocarcinoma (GAC). Nevertheless, the introduction of multidetector-row computed tomography (MDCT) allows accurate studies to be performed. To compare the diagnostic yield of EUS and MDCT in loco-regional preoperative staging of gastric adenocarcinoma. This was a retrospective and comparative study of all surgical patients with GAC and preoperative staging by EUS and 64-row MDCT. The results for each case were compared with the histological data. Seventy seven surgical patients with GAC were identified and forty two had a complete preoperative staging and were finally included in the study. With regard to overall accuracy of T staging, EUS was superior to MDCT (62% vs 50%). In a subanalysis of early stages (T1-T2) and advanced stages (T3-T4), accuracy and sensitivity (S) were higher for EUS than for MDTC (83.3% vs 64.29% and 84.4% vs 59.5% respectively), although this did not reach statistical significance. The overall accuracy and sensitivity of EUS for N staging was lower than that for MDCT, although neither comparison reached statistical significance (57% vs 64% and 29% vs 55%). EUS diagnostic yield is similar to new MDCT with regard to T and N preoperative staging of GAC. Nevertheless, both techniques should be considered as complementary until more extensive and randomized studies can confirm these results.

  6. Photodynamic therapy (PDT) with endoscopic ultrasound for the treatment of esophageal cancer

    NASA Astrophysics Data System (ADS)

    Woodward, Timothy A.; Wolfsen, Herbert C.

    2000-05-01

    In 1995, PDT was approved for palliative use in patients with esophageal cancer. We report our experience using PDT to treat esophageal cancer patients previously treated with combination chemotherapy and radiation therapy. In our series, nine patients referred for PDT with persistent esophageal cancer after chemo-radiation therapy. We found: (1) All patients were men with a mean age of 63 years and eight out of nine had adenocarcinoma with Barrett's esophagus; (2) All patients required endoscopic dilation after PDT; (3) At a mean follow up of 4 months, two T2N0 patients had no demonstrable tumor and all three T3N0 patients had greater than 50% tumor reduction (the partially responsive T3N0 patients will be offered repeat PDT); (4) Patients with metastatic disease (T3N1 or M1) had effective dysphagia palliation. Thus, PDT is safe and effective in ablating all or most tumor in patients with persistent esophageal cancer after chemotherapy and radiation therapy.

  7. The Diagnostic Accuracy of Linear Endoscopic Ultrasound for Evaluating Symptoms Suggestive of Common Bile Duct Stones.

    PubMed

    Wang, Min; He, Xu; Tian, Chuan; Li, Jian; Min, Feng; Li, Hong-Yan

    2016-01-01

    Background. In order to assess the diagnostic accuracy of linear EUS for evaluating clinically suggestive CBD stones in high-risk groups. Methods. 202 patients with clinically suggestive CBD stones in high-risk groups who underwent linear EUS examination between January 2012 and January 2015 were retrospectively reviewed. Endoscopic retrograde cholangiopancreatography (ERCP) with stone extraction or surgical choledochoscopy was only performed when a CBD stone was detected by linear EUS. Cases that were negative for CBD stones were followed up for at least 6 months. Results. Of 202 enrolled patients, 126 were positive for CBD stones according to linear EUS findings. 124 patients successfully underwent ERCP, and ERCP failed in 2 who were later successfully treated by surgical intervention. There were 2 false-positive cases with positive findings for CBD stones on ERCP. Among 76 patients without CBD stones, no false-negative cases were identified during the mean 6-month follow-up. Linear EUS had sensitivity, specificity, and positive and negative predictive values for the detection of CBD stones of 100%, 92.88%, 98.21%, and 100%, respectively. Conclusions. Linear EUS is a safe and efficacious diagnostic tool for evaluating clinically suggestive CBD stones with high risk of choledocholithiasis. Performing linear EUS prior to ERCP in patients with symptoms suggestive of CBD stones can reduce unnecessary ERCP procedures.