Elastography, ultrasound, musculoskeletal pathology, functional study 1. Radiographic technique sonoelastography sonoelastography is the term used when ultrasound is used to assess elastography. Novel methods for elastography of soft tissue using. The basic principle of te is that the propagation velocity of a wave. Neil cozens, in clinical ultrasound third edition, 2011. To evaluate diagnostic performance of realtime tissue elastography rte with a low frequency convex array probe for distinguishing benign from malignant hepatic tumors through transabdominal examination, elasticity images of 210 liver tumors were obtained by eub7500 hitachi medical systems and 3. Inadequate margins in breastconserving surgery bcs are associated with an increased likelihood of local recurrence of breast cancer. Compression, or strain, is the most affordable and commonly found ultrasound elastography option. So called shear wave transient elastography applied in fibroscan apparatus is a type of the aforementioned imaging method. Ge healthcare has announced that elastography capabilities have been added to its flagship logiq e9 ultrasound platform. Implementation of elastography score and strain ratio in. Object detection in ultrasound elastography for use in. Elastography uses mechanical compression to analyze the stiffness of.
In terms of accuracy, swe compares well with fibroscan and has been shown to be more reliable in obese patients and those with ascites. Ultrasound elastography allows our radiologists to map the elastic properties of soft tissue. Youngs modulus cannot be reconstructed as the stress within the tissues. Philips shear wave elastography simplifies liver assessment, making obtaining liver stiffness measurements fast and easy.
Highfrequency sound waves are used to measure the softness or hardness of tissue, which helps your doctor diagnose or track certain conditions and diseases. The elastic image provides more information and less noise. Upon completion of this educational activity the participant will be able to outline the strengths and weaknesses of both strain and shear wave elastography and discuss the principles and capabilities of both methods. Introduction displacement or time delay estimation in ultrasound images is an essential step. Ultrasound elastography naked engineering nakedscientists. Magnetic resonance elastography mre shows significant. This noninvasive, reproducible, and easily performed method of assessing liver tissue stiffness may help reduce, or even avoid, the need for conventional liver biopsies 1. Ultrasound elastography provides a functional assessment of the liver, informing on tissue elasticity and thus on the disease stage. Review article jsum ultrasound elastography practice guidelines breast kazutaka nakashima1 tsuyoshi shiina2 masaru sakurai3 katsutoshi enokido4 tokiko endo5 hiroko tsunoda6 etsuo takada7 takeshi umemoto8 ei ueno8 1 department of general surgery, kawasaki medical school, okayama, japan. Ultrasound elastography, elasticity imaging, strain imaging, ablation, liver, hepatocellular carcinoma, hcc, expectation maximization, em, physicsbased priors 1. Efsumb guidelines and recommendations on the clinical use of ultrasound elastography. Ge adds elastography capability to logiq e9 ultrasound.
To show that segmentation was possible on elastic images, nine algorithms were implemented in matlab and used on three distinct images for object detection. Regularized tracking of shearwave in ultrasound elastography mahmoud derakhshan horeh, amir asif, and hassan rivaz electrical and computer engineering, concordia university, montreal, qc, canada h3g 1m8 perform centre, concordia university, montreal, qc, canada h4b 1r6 abstract ultrasound elastography involves imaging tissue while it undergoes. Ultrasound project report langechuan liu october 2009 this report has two parts. In part i, the answers to the questions asked in the project will be answered. Ultrasound elastography is a noninvasive imaging method which introduced about two decade ago to image the elasticity of soft tissues. Review article jsum ultrasound elastography practice. Ultrasound elastography using three images hassan rivaz, emad m.
A matlab toolbox for working with magnetic resonance elastography mre images. There are two common elastography techniques found on ultrasound machines. In particular, ageing processes, the appearance of acute and chronic inflammation, or malignant processes have a lasting effect on the elastic nature. Furthermore, the bmode imaging capabilities of a diagnostic ultrasound system can be leveraged to provide image guidance of the exact location where shear wave elastography is performed, helping to ensure that a stiffness. An swe procedure also allows for a formal ultrasound study of the liver and upper abdomen at the same time. Visualization of the strain map calculated from this displacement can help identify tissue features, such as. Department of radiology, molecular imaging program at stanford, stanford university, school of medicine, stanford, ca, usa. Substituting these values in the equation for the bulk modulus b gives us.
Quasistatic elastography involves comparing precompression and postcompression ultrasound us images to measure the displacement of speckles. Two elastography ultrasound units were installed in the same room, and the interval between shearwave and strain elastography. Hence, the elastography has attracted attentions as a diagnostic technique especially about diseases that lead to. Velocity c l varies from 1410 ms in fat to approximately 1630 ms in muscles. We talk to graham treese about how he is improving ultrasound machines to make them better at diagnosing cancer. This measurement is used to determine elasticity of the tissue, which is useful in distinguishing hard and soft areas. After i used the ultrasound on the patient, after the acquisition of the images, i can use the machines software in postprocessing use of roi at different points to get to know the value of kilopascal. Elastography provides a noninvasive evaluation of the stiffness of a lesion. Principles of elastography ultrasound video lecture by.
Ultrasoundbased elastography provides noninvasive approaches for assessing hepatic fibrosis. I can use matlab to do in post processing measurements of. Noninvasive imaging of youngs modulus and poissons. Displacement estimation is an essential step for ultrasound elastography and numerous techniques have been proposed to improve its quality using two frames of ultrasound rf data. A noninvasive technique in which the elasticity of soft tissue is assessedusually by ultrasonographyduring application of mechanical compression or vibration. Breast elastography is a new sonographic imaging technique which provides information on breast lesions in addition to conventional ultrasonography us and mammography. This measurement, known as an metavir score, helps in diagnosing or confirming a condition what should i expect during my elastography ultrasound. This means it can be reflected off very small surfaces. Stiffness abbreviations age advanced glycation end products csa crosssectional area ecm extracellular matrix mre magnetic resonance elastography rf rectus femoris use ultrasound elastography vi vastus intermedius vl vastus lateralis vm vastus medialis introduction agerelated effects on skeletal muscle. Ultrasound elastography, also termed sonoelastography, is being used increasingly in clinical practice to aid the diagnosis and management of. Tanter is cofounder and shareholder of supersonic imagine company.
This technique is based on ultrasound tracking of quasistatic. Application of realtime tissue elastography with a low. Shear wave elastography is a noninvasive technique used in ultrasound to determine fibrosis, or stiffness of liver tissue. In this report i will provide supplementary explanations and discussions to the questions. Shear wave ultrasound liver assessment philips ultrasound. A sonographer will perform an abdominal scan to evaluate your liver, gallbladder, pancreas and spleen. Among the various approaches to elastography, perhaps the most common is that pioneered by ophir and coworkers ophir et al 1991. Elastographic imaging makes it possible to image tissue density, something which is not necessarily discernible with norma bmode imaging. Elastography is a newer technique that exploits the fact that a pathological process alters the elastic properties of the involved tissue. Ultrasonic transducers technical notes basic ultrasonic principles 404 a.
Implementation of elastography score and strain ratio in combination with bmode ultrasound avoids unnecessary biopsies of breast lesions. Ultrasound elastography in the head and neck 257 be problematic if there is a focal convex bulge of the skin overlying the tissue of interest because, under these cir. Besides vibration controlled transient elastography vcte, which is available only on the fibroscan 502 touch device and is the most validated technique for the assessment of liver stiffness, shear wave elastography techniques are implemented in conventional ultrasound systems, thus allowing the morphological evaluation of the liver in bmode. Elastography minisite home lectures journal articles news stories press release white papers welcome to the sonoworld elastography minisite on ultrasound elastography principles, clinical applications, diagnosis and recent developments. The speaker discusses principles surrounding strain and shear wave elastography. Lots of cancers cause stiff masses that arent recognized simply by conventional ultrasound. This change in elasticity is detected and imaged using elastography. Implementation of an accurate, intraoperative margin assessment tool may reduce this reexcision rate. For most of the questions, please refer to the commented matlab code attached to this report. A reliable, noninvasive marker to help clinicians evaluate. Ultrasoundbased hepatic elastography origins, limitations, and applications eric b. Elastography is a new dynamic technique that combines manual transducer compression, or the electronic equivalent, with ultrasound to provide an estimation of tissue stiffness by measuring the degree of distortion of the thyroid nodule. Because cancer is 5 to 28 times stiffer than normal surrounding soft tissue, strain images of tissues with cancer have been used to detect and classify tumours. The input is raw rf data, while the output can be normal ultrasound bmode image, a velocity image axial velocity distribution, an axial strain image or an elastrographic image.
Review of techniques and clinical applications rosa m. A matlab toolbox for working with magnetic resonance elastography mre images gruss mrrcmre matlabtoolbox. Static elastography static elastography uses a uniform compression at the surface of the body to cause deformation of the tissue. The purpose of this article is to provide an overview of ultrasound and mr elastography, including a glossary of relevant terminology, a classification of elastography techniques, and a discussion of their respective strengths and limitations. Ultrasound elasticity imaging, or elastography, offers an attractive adjunct to. Mechanics of ultrasound elastography article pdf available in proceedings of the royal society a mathematical physical and engineering sciences 4732199 march 2017 with 384 reads. Ultrasound elastography use 1, ultrasound shear wave elastography swe 2 and magnetic resonance elastography mre 3 techniques have shown to be capable of generating ym images 4,5,6. Hi, everybody, im using an ultrasound scanner that allows you to acquire data with elastosonography shear wave method. Ultrasound elastography, allows complete automation of hifu treatment due to the enhanced image, that elastography provides.
Research suggests that instead of a costly and painful biopsy procedure, an easy ultrasound exam could. It is an ultrasoundbased modality that quantitatively assesses liver stiffness ls as a surrogate for fibrosis. Elastography definition of elastography by medical. The benefits of elastography in ultrasound providian medical. This information is obtained with greatest ease, non invasively and very rapidly at the bedside. Introduction thirty athletes practicing professional sports were evaluated in the steps after posttrauma muscular distraction of the inferior limb, using a stateoftheart ultrasound equipment provided with elastography method.
Using various methods, the ultrasound can display or quantify various levels of stiffness in tissue. Other methods for assessing liver fibrosis, including liver biopsy, magnetic resonance elastography, and serologic testing, are discussed separately. Early reports suggest that elastography may help to differentiate malignant from. Currently, approximately 20% of bcs patients require repeat surgery due to inadequate margins at the initial operation. The compression is applied by the user and the ultrasound scanner calculates and displays the induced deformation in the imaging plane.
448 389 321 338 268 163 457 1427 558 1440 1191 811 797 738 593 1093 98 215 755 233 1215 1174 420 871 1562 154 743 52 481 1023 35 931 724 801