Plaque characterization using shear wave elastography—evaluation of differentiability and accuracy using a combined ex vivo and in vitro setup

As a skeletal muscle is being stretched, it reacts with increasing passive resistance. This passive force component is important for normal muscle function [1]. Unfortunately, direct measurement of muscle force is still beyond the current state-of-the-art. In the present study, we investigate the feasibility of using Supersonic shear wave elastography (SWE) to indirectly measure passive muscle force using an ex-vivo chicken model.

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The effect of stretching on transmural shear wave anisotropy in cardiac shear wave elastography: An ex vivo and in silico study

2017 IEEE International Ultrasonics Symposium (IUS) ◽

10.1109/ultsym.2017.8091930 ◽

2017 ◽

Cited By ~ 1

Author(s):

Annette Caenen ◽

Abdullah Thabit ◽

Mathieu Pernot ◽

Darya Shcherbakova ◽

Luc Mertens ◽

...

Keyword(s):

Shear Wave ◽

In Silico ◽

Ex Vivo ◽

Shear Wave Elastography ◽

In Silico Study

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Shear Wave Elastography Quantifies Stiffness in Ex Vivo Porcine Artery with Stiffened Arterial Region

Ultrasound in Medicine & Biology ◽

10.1016/j.ultrasmedbio.2016.05.021 ◽

2016 ◽

Vol 42 (10) ◽

pp. 2423-2435 ◽

Cited By ~ 25

Author(s):

Erik Widman ◽

Elira Maksuti ◽

Carolina Amador ◽

Matthew W. Urban ◽

Kenneth Caidahl ◽

...

Keyword(s):

Shear Wave ◽

Ex Vivo ◽

Shear Wave Elastography ◽

Porcine Artery

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Smart ultrasound device for real-time myocardial stiffness quantification of the human heart

European Heart Journal - Cardiovascular Imaging ◽

10.1093/ehjci/jeaa356.008 ◽

2021 ◽

Vol 22 (Supplement_1) ◽

Author(s):

O Pedreira ◽

C Papadacci ◽

S Chatelin ◽

M Correia ◽

M Tanter ◽

...

Keyword(s):

Real Time ◽

Shear Wave ◽

Acoustic Radiation ◽

Ex Vivo ◽

Radiation Force ◽

Septal Wall ◽

Shear Wave Imaging ◽

Wave Imaging ◽

Good Agreement

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – EU funding. Main funding source(s): ERC Introduction Myocardial stiffness (MS) is crucial to understand cardiac biomechanics and evaluate cardiac function. We recently demonstrated that shear wave imaging using acoustic radiation force can provide quantitative end-diastolic MS in human patients [1] . However, the dependence of shear wave velocity with myofiber orientation remained a limitation and required to perform Shear Wave Velocity (SWV) estimations from different probe orientations which is challenging in clinical practice. We propose a new approach to provide real-time quantitative assessment of MS without dependence of the probe orientation based on a dedicated smart ultrasound (US) device. Methods A new US probe was designed and manufactured to generate acoustic radiation force along the central axis and track the SWV simultaneously along three different orientations to obtain an elliptic profile of SWS. The probe was connected to dedicated electronics and software to provide real-time end-diastolic MS with ECG gating. Validation was performed on 4 in-vitro calibrated phantoms (0.92 – 1.49 – 2.58 – 3.49 m/s) and on ex vivo porcine hearts. MS along and across the fibers were compared to the values measured by conventional shear wave imaging with a linear probe mounted on a rotation motor (angular step of 10°) (Aixplorer, Supersonic imaging). Finally, the in vivo feasibility and reproducibility of measuring MS of the antero-septal wall and of the right ventricular (RV) wall was assessed transthoracically on four human volunteer . Results In vitro results on phantoms showed a good agreement with calibrated value (r2 = 0.98, std = 4.8%). Elliptic profiles on ex-vivo porcine heart showed good agreement with Aixplorer measurements acquired at different angles, with a relative difference along the long axis (LA) of: Δ=7.0%, Δ=7.1%, Δ=9% respectively for left ventricle (LV), right ventricle (RV) and septum. Finally, myocardial SWV assessment in human volunteers was obtained successfully on the RV and on the septum in late diastole. The mean MS was 1.79+/- 0.15 m/s along the fiber direction, the fractional anisotropy (FA) was 0.25 +/- 0.06 on septal wall in good agreement with previous results [1] and 1.06 +/- 0.11 m/s along fibers orientation and a FA of 0.27 +/- 0.08 on RV. Finally the beat to beat reproducibility of MS measurement was estimated to be 8.22%. Conclusion The new smart US device allowed non-invasive quantification of anisotropic myocardial tissues in real time. Results showed the accuracy of the methods. This approach could offer a new clinical tool for the evaluation of the myocardium in cardiomyopathies and in heart failure patients. Abstract Figure. SWV on myocardium human volonteer

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A Cross-Machine Comparison of Shear-Wave Speed Measurements Using 2D Shear-Wave Elastography in the Normal Female Breast

Applied Sciences ◽

10.3390/app11209391 ◽

2021 ◽

Vol 11 (20) ◽

pp. 9391

Author(s):

Emma Harris ◽

Ruchi Sinnatamby ◽

Elizabeth O’Flynn ◽

Anna M. Kirby ◽

Jeffrey C. Bamber

Keyword(s):

Adipose Tissue ◽

Shear Wave ◽

Subcutaneous Adipose Tissue ◽

Wave Speed ◽

Shear Wave Elastography ◽

Shear Wave Speed ◽

Skin Region ◽

Subcutaneous Adipose

Quantitative measures of radiation-induced breast stiffness are required to support clinical studies of novel breast radiotherapy regimens and exploration of personalised therapy, however, variation between shear-wave elastography (SWE) machines may limit the usefulness of shear-wave speed (cs) for this purpose. Mean cs measured in four healthy volunteers’ breasts and a phantom using 2D-SWE machines Acuson S2000 (Siemens Medical Solutions) and Aixplorer (Supersonic Imagine) were compared. Shear-wave speed was measured in the skin region, subcutaneous adipose tissue and parenchyma. cs estimates were on average 2.3% greater when using the Aixplorer compared to S2000 in vitro. In vivo, cs estimates were on average 43.7%, 36.3% and 49.9% significantly greater (p << 0.01) when using the Aixplorer compared to S2000, for skin region, subcutaneous adipose tissue and parenchyma, respectively. In conclusion, despite relatively small differences between machines observed in vitro, large differences in absolute measures of shear wave speed measured were observed in vivo, which may prevent pooling of cross-machine data in clinical studies of the breast.

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Ex Vivo Assessment of Sentinel Lymph Nodes in Breast Cancer Using Shear Wave Elastography

Journal of Ultrasound in Medicine ◽

10.7863/ultra.15.03039 ◽

2015 ◽

Vol 35 (2) ◽

pp. 271-277 ◽

Cited By ~ 18

Author(s):

Fahrettin Kilic ◽

Mehmet Velidedeoglu ◽

Tulin Ozturk ◽

Sedat Giray Kandemirli ◽

Atilla Suleyman Dikici ◽

...

Keyword(s):

Breast Cancer ◽

Lymph Nodes ◽

Shear Wave ◽

Ex Vivo ◽

Shear Wave Elastography ◽

Sentinel Lymph Nodes

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Influencing Factors of 2D Shear Wave Elastography of the Muscle – An Ex Vivo Animal Study

Ultrasound International Open ◽

10.1055/a-0619-6058 ◽

2018 ◽

Vol 04 (02) ◽

pp. E54-E60 ◽

Cited By ~ 5

Author(s):

Marga Rominger ◽

Pascal Kälin ◽

Monika Mastalerz ◽

Katharina Martini ◽

Volker Klingmüller ◽

...

Keyword(s):

Shear Wave ◽

Ex Vivo ◽

Operation Mode ◽

Region Of Interest ◽

Shear Wave Elastography ◽

Longitudinal Direction ◽

Test Configuration ◽

Linear Probe ◽

The Impact ◽

Placement Depth

AbstractTo evaluate measurement confounders on 2D shear wave elastography (2D-SWE) elastography of muscle. Ex vivo, porcine muscle was examined with a GE LOGIQ E9 ultrasound machine with a 9 L linear (9 MHz) and C1-6 convex probe (operating at 2.5 or 6 MHz). The influence of different confounders on mean shear wave velocity (SWVmean) was analyzed: probes, pressure applied by probe, muscle orientation, together with the impact of different machine settings such as frequency, placement depth and size of region of interest (ROI). The mean of twelve repeated SWVmean measurements (m/s) and coefficient of variation (CV; standard deviation/mean in %) were assessed for each test configuration. Reproducibility (CV) and maximum possible tissue depth of the linear probe were inferior to the convex probe. With the linear probe, there was a linear decrease of SWVmean with placement depth from 4.56 m/s to 1.81 m/s. A significant increase of SWVmean (p<0.001) was observed for larger ROI widths (range 3.96 m/s to 6.8 m/s). A change in the machine operation mode ('penetration' instead of 'general') led to a significant increase of SWVmean (p=0.04). SWVmean in the longitudinal direction of muscle was significantly higher than in cross section (p<0.001) (e. g. 4.56 m/s versus 3.42 m/s). An increase of linear probe pressure significantly increased muscle SWVmean from 5.29 m/s to 7.21 m/s (p<0.001). 2D-SWE of muscle is influenced by a wealth of parameters. Therefore, standardization of measurement is advisable before application in clinical research studies and routine patient assessment.

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