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Auswahl der wissenschaftlichen Literatur zum Thema „Quantitative Transient Elastography“
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Zeitschriftenartikel zum Thema "Quantitative Transient Elastography"
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Lupsor-Platon, Monica, Teodora Serban, Alexandra-Iulia Silion, Alexandru Tirpe und Mira Florea. „Hepatocellular Carcinoma and Non-Alcoholic Fatty Liver Disease: A Step Forward for Better Evaluation Using Ultrasound Elastography“. Cancers 12, Nr. 10 (28.09.2020): 2778. http://dx.doi.org/10.3390/cancers12102778.
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The increasing prevalence of non-alcoholic fatty liver disease (NAFLD) in the general population prompts for a quick response from physicians. As NAFLD can progress to liver fibrosis, cirrhosis, and even hepatocellular carcinoma (HCC), new non-invasive, rapid, cost-effective diagnostic methods are needed. In this review, we explore the diagnostic performance of ultrasound elastography for non-invasive assessment of NAFLD and NAFLD-related HCC. Elastography provides a new dimension to the conventional ultrasound examination, by adding the liver stiffness quantification in the diagnostic algorithm. Whilst the most efficient elastographic techniques in staging liver fibrosis in NAFLD are vibration controlled transient elastography (VCTE) and 2D-Shear wave elastography (2D-SWE), VCTE presents the upside of assessing steatosis through the controlled attenuation parameter (CAP). Hereby, we have also critically reviewed the most important elastographic techniques for the quantitative characterization of focal liver lesions (FLLs), focusing on HCC: Point shear wave elastography (pSWE) and 2D-SWE. As our paper shows, elastography should not be considered as a substitute for FLL biopsy because of the stiffness values overlap. Furthermore, by using non-invasive, disease-specific surveillance tools, such as US elastography, a subset of the non-cirrhotic NAFLD patients at risk for developing HCC can be detected early, leading to a better outcome. A recent ultrasomics study exemplified the wide potential of 2D-SWE to differentiate benign FLLs from malignant ones, guiding the clinician towards the next steps of diagnosis and contributing to better long-term disease surveillance.
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Liu, Yu, Jingfei Liu, Brett Z. Fite, Josquin Foiret, Asaf Ilovitsh, J. Kent Leach, Erik Dumont, Charles F. Caskey und Katherine W. Ferrara. „Supersonic transient magnetic resonance elastography for quantitative assessment of tissue elasticity“. Physics in Medicine and Biology 62, Nr. 10 (20.04.2017): 4083–106. http://dx.doi.org/10.1088/1361-6560/aa6674.
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Taru, Madalina-Gabriela, Lidia Neamti, Vlad Taru, Lucia Maria Procopciuc, Bogdan Procopet und Monica Lupsor-Platon. „How to Identify Advanced Fibrosis in Adult Patients with Non-Alcoholic Fatty Liver Disease (NAFLD) and Non-Alcoholic Steatohepatitis (NASH) Using Ultrasound Elastography—A Review of the Literature and Proposed Multistep Approach“. Diagnostics 13, Nr. 4 (19.02.2023): 788. http://dx.doi.org/10.3390/diagnostics13040788.
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Non-alcoholic fatty liver disease (NAFLD), and its progressive form, non-alcoholic steatohepatitis (NASH), represent, nowadays, real challenges for the healthcare system. Liver fibrosis is the most important prognostic factor for NAFLD, and advanced fibrosis is associated with higher liver-related mortality rates. Therefore, the key issues in NAFLD are the differentiation of NASH from simple steatosis and identification of advanced hepatic fibrosis. We critically reviewed the ultrasound (US) elastography techniques for the quantitative characterization of fibrosis, steatosis, and inflammation in NAFLD and NASH, with a specific focus on how to differentiate advanced fibrosis in adult patients. Vibration-controlled transient elastography (VCTE) is still the most utilized and validated elastography method for liver fibrosis assessment. The recently developed point shear wave elastography (pSWE) and two-dimensional shear wave elastography (2D-SWE) techniques that use multiparametric approaches could bring essential improvements to diagnosis and risk stratification.
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Shirokova, Elena N., Chavdar S. Pavlov, Anna D. Karaseva, Aliya M. Alieva, Alla V. Sedova und Vladimir T. Ivashkin. „Elastography in the Diagnosis of Non-Alcoholic Fatty Liver Disease“. Annals of the Russian academy of medical sciences 74, Nr. 1 (03.04.2019): 5–13. http://dx.doi.org/10.15690/vramn1071.
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Currently, there has been a progressive increase in prevalence of one of the most common diffuse chronic liver diseases ― non-alcoholic fatty liver disease (NAFLD). Assessment of the stages of liver fibrosis and steatosis is prognostically significant in diagnosis of NAFLD. Routine diagnostic methods are either not able to accurately assess the severity of fibrosis and steatosis (ultrasound, laboratory tests), or cannot be used as a simple screening tool (liver biopsy) due to such limitations as invasiveness, dependence on pathologist qualification, high cost, and limited region of interest. Over the last two decades, the great progress has been made in non-invasive visualization of pathological changes in liver diseases. In this review, we examined the diagnostic characteristics of the most widely used non-invasive imaging methods in clinical practice, available for quantitative determination of fat and fibrosis in the liver: transient elastography with controlled attenuation parameter (CAP), acoustic radiation force impulse (ARFI) and shear wave elastography (SWE). Comparing these methods and their limitations, we came to conclusion, that elastographic methods (slightly more ARFI and SWE) are able to verify the F3, F4 stages of fibrosis in NAFLD with high sensitivity and specificity (90%); however, they are less accurate for early stages. Elastographic techniques have moderate accuracy in identifying the degree of steatosis due to the lack of uniform standardized cut-off values of CAP.
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Patra, Sayantan, und Shabnam Bhandari Grover. „Physical Principles of Elastography: A Primer for Radiologists“. Indographics 01, Nr. 01 (Januar 2022): 027–40. http://dx.doi.org/10.1055/s-0042-1742575.
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AbstractElastography is the noninvasive method of qualitative and quantitative evaluation of strain and elastic modulus distribution in soft tissues. In simpler terms, elastography is the science of measuring tissue stiffness, the deviation of which correlates with pathology of the tissue/organs being evaluated. Whereas, elasticity, refers to the property of solid matter to return to their original shape and size after removal of the deforming forces. In all forms of elastography, irrespective of the types of deforming forces or moduli, the deformation of tissue occurs in the form of shear deformation. The velocity of shear waves in the deformed tissue depends on its density and on the shear modulus. The direction of propagation of shear wave is perpendicular to the inciting mechanical or acoustic wave. The shear wave is then subsequently tracked using multiple tracking pulses, which measures tissue displacement in response to the passing shear wave. The calculated speed of the shear wave is then converted to conventional Young's modulus for the purpose of computing the tissue stiffness.The currently used elastography techniques are static or quasi-static elastography and dynamic elastography. Strain elastography (a form of static or quasi-static elastography) is based on the principle of acquisition of radio-frequency (RF) signals before and after the application of a deforming force in the form of slight compression of tissue by a transducer. RF signals are compared between the pre-compression image data set and the post-compression image data set and correlated between the two data sets.Dynamic elastography may be either ultrasound (US) based or magnetic resonance (MR) based. The types of dynamic US elastography are: acoustic radiation force impulse imaging (ARFI), transient elastography (TE), point shear wave elastography (pSWE), and shear wave elastography (SWE). ARFI uses a standard transducer to produce and propagate rapid bursts of long focused ultrasound pulses, also called as “push pulses” which cause tissue deformity, the propagation of which is tracked using radio-frequency echo tracking. In TE, a probe mounted on a vibrator is used to produce a small thump by piston like motion of transducer. The shear wave which arises from the edges of the transducer is tracked using high pulse repetition frequency tissue Doppler and computed using M-mode for display of quantitative parameters. Point shear wave, also known as quantitative ARFI, uses shear waves generated using transient tissue displacement caused by ARFI and are subsequently subjected to tracking by Doppler. Shear wave elastography is based on the principles of imaging shear wave speed. An acoustic radiation force impulse is transmitted along the acoustic axis to produce tissue displacement and deformation at points of acoustic axis. The generated shear wave is imaged using RF echo tracking over a grid of points, which is translated into a real time image. MR elastography is a dynamic technique and the basic principles of MR elastography are the same as other forms of dynamic elastography. MR elastography has limited utility in iron-overload states and in addition, due to the large amount of time required for acquisition, the technique is not suitable for unstable patients.This review presents a simplified summary of the principles of elastography along with definition of the terms and the types of elastography which are currently available to radiologists for clinical application and concludes with a brief on the newer developments for the future.
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Sporea, Ioan, Ruxandra Mare, Raluca Lupușoru, Alexandra Sima, Roxana Șirli und Romulus Timar. „Liver Stiffness Evaluation by Transient Elastography in Type 2 Diabetes Mellitus Patients with Ultrasound-proven Steatosis“. Journal of Gastrointestinal and Liver Diseases 25, Nr. 2 (01.06.2016): 167–74. http://dx.doi.org/10.15403/jgld.2014.1121.252.lsf.
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Background & Aims: Nonalcoholic fatty liver disease (NAFLD) is one of the most common chronic liver diseases worldwide. The aim of our study was to evaluate a population of diabetic patients regarding the severity of liver steatosis and liver fibrosis.
Methods: The study included 392 type 2 diabetic patients prospectively randomized, evaluated in the same session by transabdominal ultrasound to assess steatosis and by liver elastography to assess fibrosis (Transient Elastography – TE, FibroScan, EchoSens). Steatosis severity was graded using a semi-quantitative scale (S0-no steatosis; S1-mild steatosis; S2-moderate steatosis; S3-severe steatosis). For differentiation between stages of liver fibrosis, the following cut-off values were used (Wong et al., 2010): F2-F3: 7-10.2kPa, F4≥10.3 kPa.
Results: Reliable elastographic measurements were obtained in 76% (298/392) patients. By using the proposed cut-off values, significant fibrosis (F2-F3) was found in 18.8% (56) patients with steatosis, while 13.8% (41) had cirrhosis (F4). Significant fibrosis (F2-F3) was found in 20.4% (20/98) of the patients with S1, in 18.6% (22/118) of those with S2 and in 31.8% (14/44) of those with S3, while cirrhosis (F4) was diagnosed in 7.1% (7/98) patients with S1, in 20.3% (24/118) of those with S2 and in 22.7% (10/44) of those with S3.
Conclusions: Liver steatosis diagnosed by ultrasound is very frequently found in type 2 diabetes mellitus patients, more than half of them having moderate/severe steatosis. A significant liver stiffness increase was found in more than 30% of these patients. Liver stiffness assessment in type 2 diabetic patients should be performed systematically to identify those with significant liver fibrosis. .
Abbreviations: 2D-SWE: Two Dimensional Shear Waves Elastography; ALT: alanine aminotransferase; AP: alkaline phosphatase; ARFI: Acoustic Radiation Force Impulse; AST: aspartate aminotransferase; AUROC: area under the receiver operating characteristic; BMI: body mass index; DM: diabetes mellitus; GGT: gammaglutamyl transpeptidase; HbA1c: glycated hemoglobin; HBsAg: hepatitis B virus surface antigen; HBV: hepatitis B virus; HCV: hepatitis C virus; LC: liver cirrhosis; LS: liver stiffness; NAFLD: nonalcoholic fatty liver disease; NASH: nonalcoholic steatohepatitis; TE: transient elastography; US: ultrasound.
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Diomidova, Valentina N., Olga V. Valeeva, Lidiya N. Vasilyeva und Ekaterina A. Razbirina. „INFORMATIVENESS OF TRANSIENT AND TWO-DIMENSIONAL SHEAR WAVE ELASTOGRAPHY IN ASSESSING OF LIVER STIFFNESS IN POST-COVID-19 AND CARDIOHEPATIC SYNDROMES“. Acta medica Eurasica, Nr. 4 (27.12.2023): 31–43. http://dx.doi.org/10.47026/2413-4864-2023-4-31-43.
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Ultrasound elastography of diffuse liver diseases allows to assess liver stiffness and predict the further course of the disease, determine the tactics of patient’s management for post-Covid and cardiohepatic syndrome. The purpose of the research – to study the diagnostic informativeness and evaluate the correlation between one-dimensional and two-dimensional shear wave elastography technologies with elastometry in assessing liver stiffness in patients with post-COVID and cardiohepatic syndromes. Materials and methods. A comparative analysis of the information content and correlation between the results of one-dimensional and two-dimensional shear wave elastography of the liver was carried out in 85 patients with post-COVID (N1; n = 30) and cardiohepatic (N2; n = 25) syndromes. The control group (N3; n = 30) consisted of patients without the new coronavirus infection COVID-19 and without any pathology of the liver and biliary system. In the control group, the study of liver parenchyma stiffness using shear wave elastography was carried out by lobes and segments. Standard variation statistics algorithms were used, taking into account the type of data distribution in the statistical analysis. Quantitative indicators with a normal distribution were described using arithmetic means (M) and standard deviations (SD), boundaries of the 95% confidence interval (95% CI). In the absence of a normal distribution, quantitative data were described using the median (Me) and lower and upper quartiles (Q1–Q3). Research results. The stiffness values (Emean) in the projection of segments VI, VII had larger values (p = 0.02) when compared with other segments. We obtained the following Emean values in transient elastography: in the group of patients with post-COVID syndrome (N1) – 10.02 kPa; in the group of patients with chronic heart failure (N2) – 14.09 kPa, which turned out to be significantly higher than the stiffness of the liver parenchyma among healthy individuals, where the Emean value was 4.90 kPa (p = 0.05). With shear wave elastography, the results were also higher in the group of patients with chronic heart failure (N2), where Emean was 20.90 kPa, compared to the group of patients with post-COVID syndrome (N1) – 11.86 kPa. Conclusions. The results of shear wave elastography were successful in 100% of cases, the results of transient elastography in 84.6% of cases. Correlation analysis of connections in a group of patients with chronic heart failure according to TE and SWE showed a weak positive direct linear correlation. A positive direct linear correlation of medium strength was obtained in assessing the correlation in the group of patients with post-COVID syndrome.
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Kim, Hyun-Jin, Hae-Kag Lee, Jae-Hwan Cho und Han-Jun Yang. „Quantitative comparison of transient elastography (TE), shear wave elastography (SWE) and liver biopsy results of patients with chronic liver disease“. Journal of Physical Therapy Science 27, Nr. 8 (2015): 2465–68. http://dx.doi.org/10.1589/jpts.27.2465.
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Esposto, Giorgio, Paolo Santini, Linda Galasso, Irene Mignini, Maria Elena Ainora, Antonio Gasbarrini und Maria Assunta Zocco. „Shear-wave elastography to predict hepatocellular carcinoma after hepatitis C virus eradication: A systematic review and meta-analysis“. World Journal of Gastroenterology 30, Nr. 10 (14.03.2024): 1450–60. http://dx.doi.org/10.3748/wjg.v30.i10.1450.
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BACKGROUND Direct-acting antiviral agents (DAAs) are highly effective treatment for chronic hepatitis C (CHC) with a significant rate of sustained virologic response (SVR). The achievement of SVR is crucial to prevent additional liver damage and slow down fibrosis progression. The assessment of fibrosis degree can be performed with transient elastography, magnetic resonance elastography or shear-wave elastography (SWE). Liver elastography could function as a predictor for hepatocellular carcinoma (HCC) in CHC patients treated with DAAs. AIM To explore the predictive value of SWE for HCC development after complete clearance of hepatitis C virus (HCV). METHODS A comprehensive literature search of clinical studies was performed to identify the ability of SWE to predict HCC occurrence after HCV clearance. In accordance with the study protocol, a qualitative and quantitative analysis of the evidence was planned. RESULTS At baseline and after 12 wk of follow-up, a trend was shown towards greater liver stiffness (LS) in those who go on to develop HCC compared to those who do not [baseline LS standardized mean difference (SMD): 1.15, 95% confidence interval (95%CI): 020-2.50; LS SMD after 12 wk: 0.83, 95%CI: 0.33-1.98]. The absence of a statistically significant difference between the mean LS in those who developed HCC or not may be related to the inability to correct for confounding factors and the absence of raw source data. There was a statistically significant LS SMD at 24 wk of follow-up between patients who developed HCC vs not (0.64; 95%CI: 0.04-1.24). CONCLUSION SWE could be a promising tool for prediction of HCC occurrence in patients treated with DAAs. Further studies with larger cohorts and standardized timing of elastographic evaluation are needed to confirm these data.
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Leung, Vivian Yee-fong, Jiayun Shen, Vincent Wai-sun Wong, Jill Abrigo, Grace Lai-hung Wong, Angel Mei-ling Chim, Shirley Ho-ting Chu et al. „Quantitative Elastography of Liver Fibrosis and Spleen Stiffness in Chronic Hepatitis B Carriers: Comparison of Shear-Wave Elastography and Transient Elastography with Liver Biopsy Correlation“. Radiology 269, Nr. 3 (Dezember 2013): 910–18. http://dx.doi.org/10.1148/radiol.13130128.
Der volle Inhalt der QuelleDissertationen zum Thema "Quantitative Transient Elastography"
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Lorée, Hugo. „Élastographie impulsionnelle : étude des artefacts et développement d’une méthode de guidage par ondes élastiques monochromatiques“. Electronic Thesis or Diss., Sorbonne université, 2020. http://www.theses.fr/2020SORUS446.
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La fibrose hépatique est une maladie chronique du foie en constante augmentation dans les pays industrialisés. Le degré de fibrose présente la particularité d’être directement corrélé à l’élasticité du foie. En quantifiant l’élasticité des tissus de manière non invasive, l’élastographie impulsionnelle fournit au praticien un outil de diagnostic majeur des maladies chroniques du foie. Couramment utilisée dans les services d’hépatologie, elle consiste à générer, à l’aide d’une sonde ultrasonore mono élément, une vibration impulsionnelle à la surface de la peau, qui va se propager dans les tissus sous forme d’une onde de cisaillement. Sa propagation est suivie en temps réel par ultrasons. Pour obtenir une mesure d’élasticité hépatique fiable, l’opérateur doit placer la sonde en regard d’une zone homogène du foie. Cette phase de localisation peut s’avérer difficile suivant l’expérience de l’opérateur, ou encore notamment lors de la mesure de patients obèses massifs.Deux axes majeurs ont été explorés au cours de cette thèse, d’une part pour améliorer l’applicabilité de l’examen sur patients obèses massifs, et d’autre part pour faciliter la localisation d’une zone de mesure optimale. Dans un premier temps, une étude des artefacts perturbant l’estimation de l’élasticité a été conduite sur simulations et in vitro. Ses résultats ont permis une meilleure compréhension de l’influence des artefacts les plus courants en élastographie impulsionnelle. Les résultats ont également conduit au développement de prototypes adaptés à la mesure du foie des patients obèses massifs. Dans un second temps, un outil de localisation a été développé pour aider l’opérateur à repérer une zone de mesure optimale. Enfin, les prototypes de sonde ainsi que la nouvelle méthode de localisation ont été testées dans le cadre d’un protocole clinique conduit à l’hôpital la Pitié-Salpêtrière sur des patients obèses massifsThe incidence of chronic liver diseases, and particularly liver fibrosis, is constantly growing in industrialized countries. Liver stiffness, which is a good surrogate marker to stage liver fibrosis, can be estimated noninvasively through transient elastography. This technique thus provides an important diagnosis tool to the specialists. Commonly used in hepatology, it consists in using a mono element ultrasound probe to generate a transient pulse at the surface of the skin that will propagate within the liver as a shear wave. Its propagation is tracked in real time using ultrafast ultrasound pulses. In order to obtain a reliable liver stiffness estimation, the probe has to be placed in front of a homogeneous region of the liver. This localization phase may be difficult depending on the experience of the operator, and the morphology of the patient, with obese patients being particularly difficult to measure.In this thesis, a first axis of research was dedicated to improve the applicability of transient elastography on massively obese patients. A second focus of research aimed at facilitating the localization of an optimal measurement window. First, the artefacts disturbing the stiffness estimation were studied through simulations and in vitro studies. It led to a better understanding of the influence of the most common artifacts in transient elastography and to the manufacturing of probe prototypes adapted to measuring massively obese patients. Secondly, a liver localization tool has been developed in order to help the operator detect an optimal measurement window. Lastly, the probe prototypes as well as the liver localization tool were tested on massively obese patients during a clinical trial carried out at the hospital la Pitié-Salpêtrière
Konferenzberichte zum Thema "Quantitative Transient Elastography"
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Marmin, Agathe, Gabrielle Laloy-Borgna, Sybille Facca, Sylvain Gioux, Stefan Catheline und Amir Nahas. „Quantitative full-field transient elastography based on digital holography“. In Optical Elastography and Tissue Biomechanics VIII, herausgegeben von Kirill V. Larin und Giuliano Scarcelli. SPIE, 2021. http://dx.doi.org/10.1117/12.2578581.
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Ramzanpour, Mohammadreza, Mohammad Hosseini-Farid, Jayse McLean, Mariusz Ziejewski und Ghodrat Karami. „A Logistic Regression Analysis for Tissue Stiffness Categorization Through Magnetic Resonance Elastography“. In ASME 2020 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/imece2020-23929.
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Abstract Magnetic resonance elastography (MRE) is commonly used as an image-based alternative for palpation of the internal organs of human body. The presence of tumor or other kind of pathologies in biological tissues can increase its stiffness. Therefore, while MRE technique is capable to provide a quantitative measurement, the qualitative description of the tissue stiffness could be potentially informative as well for physicians. MRE can be divided into several steps including the generation of waves in the tissue, measuring the field displacement of the tissue by magnetic resonance imaging devices, and then applying the constitutive based inversion algorithms to measure the material properties of the tissue. The inversion algorithms are dependent to the constitutive model in use, and moreover, it could be computationally expensive. To overcome this hindrance, in this paper, we propose a machine learning framework for categorizing the tissue stiffness based on the magnetic resonance elastography finite element simulation data. In our finite element simulation, the shear waves are generated in an axisymmetrical model by applying harmonic displacement at the center of the model with the known excitation frequency. To obtain the field displacement of the model, in the first step, the natural frequencies of the system will be calculated through numerical Block-Lanczos eigensolver algorithm. Thereafter, a transient dynamic modal analysis is carried out to find the corresponding displacement response of the tissue in different time steps of the simulation. To obtain the training dataset, ten simulations with the pre-assigned linear elastic modulus in the range of 2 to 6 kPa is conducted and the displacement of the tissue in three points at the end of the first and second cycle will be recorded as the features of the dataset. Each instance of the dataset is labelled as “Low“ or “High”, corresponding to its stiffness quantitative value lying in ranges of 2–4 kPa or 4–6 kPa. A machine learning classifying algorithm, a logistic regression hypothesis will be trained on this dataset. The trained hypothesis will be then tested on six new unseen simulation data with known elastic modulus values. The trained logistic regression was able to classify the tissue stiffness with the perfect accuracy score of 1.0. The findings of this study can be used for qualitative description of the tissue stiffness that can be beneficial for pathology diagnosis and moreover, it eliminates the need on the usage of inversion algorithms which leads to reduction in the computational complexity of tissue characterization.