ACUSON Sequoia ultrasound system
VA25 SW release
Virtual Touch 2D SWE
Quick Reference Card
siemens-healthineers.com/ultrasound
Using 2D shear wave elastography (SWE) to measure
shear velocity (Vs) in meters per second (m/s) and
elasticity (E) in kilopascal (kPa) | Liver Application
Step 1 Step 3
• Select compatible transducer1 and • Select SWE tab on touch screen
Abdomen exam preset
• If needed, roll trackball to reposition
2D SWE region of interest (ROI)
Step 2 • If desired, press Set key and roll
trackball to resize ROI
• Press VT (Virtual Touch) located on
control panel
Step 4
• Press Update on control panel to
begin acquisition
Note: During freeze, a cooling timer indicates remaining seconds
until transducer is available for image acquisition. During a short
cooling time (e.g., 1–2 seconds), the timer appears and then
disappears very quickly.
1
2D SWE imaging is compatible with 5C1, DAX: General, Abdomen;
10L4: General, Thyroid, Breast, MSK; 18L6: General, Thyroid, Breast.
Step 5 Step 7
• When acquisition is complete, system automatically • Roll trackball to position
freezes, emits one audible “beep” and activates measurement ROI
Velocity or Elasticity display mode
• If needed, rotate ROI Diameter
• Adjust Min and/or Max Velocity or Elasticity to adjust to resize measurement ROI
range of measurements displayed in ROI
• Shear wave measurements and
- Increase range if measured value exceeds range by measurement ROI depth and
displaying “High” or, diameter are displayed next to
- Decrease range if better visualization of velocity of image
stiffness differences is needed
• Rotate Shear Wave to view Quality and Displacement
displays Step 8
To enter measurement into report:
• Press Image to store image or,
• If desired, select SWE to hide / display • Press right or left Set key
2D SWE or,
• Rotate VT on control panel to change
transparency of 2D SWE
Step 9
• Unfreeze, repeat steps 4–9 to make
additional measurements
• If desired, select Unit m/s to display
the 2D SWE image as an elasticity
image in kPa
• If desired, select Live Dual to display Step 10
the 2D SWE image in full-screen
• Select Report
format
• View, delete, store, print or transfer
shear wave measurements
Step 6
• Press Caliper
• Select same measurement label each time
2 siemens-healthineers.com/ultrasound
Virtual Touch
2D SWE Liver
Application
Best Practice Techniques1
Fig. 1: Optimal technique
Fasting for at least 4 hours In the non-fasting state, the liver can have falsely increased values.
Position patient supine or slight (30°) left Optimal positioning to improve intercostal access.
lateral decubitus position with right arm
raised above head
Transducer perpendicular (90°) to skin A transducer angle < 50° to the skin surface, or use of inadequate
surface using ample gel amount of gel, can result in artificially low shear wave measurements
due to loss of transducer contact.
Take measurements in right lobe of liver, Optimal ROI placement to obtain reproducible results and avoid
in either segment 8 or 5 (Fig. 1), using cardiac motion.
intercostal scanning approach
Position the measurement ROI at least The 2D SWE ROI can be positioned closer to the liver capsule, if
1.5–2 cm below liver capsule (Fig. 1) reverberation artifacts are avoided; however, the measurement ROI
should be positioned at least 1.5-2 cm below the liver capsule.
Scanning parallel to ribs and in an Rib shadows on either side of the ROI result in poor generation and
intercostal space to avoid rib shadow propagation of the shear wave from the Acoustic Radiation Force
artifacts, optimize B-mode image (Fig. 1) Impulse (ARFI) push pulse.
so liver parenchyma is bright and large
vessels, bile ducts and rib shadows are
avoided
Perform acquisition during suspended Valsalva or deep inspiration can cause an undesired increase in central
respiration; patient may resume normal venous pressure which can falsely elevate shear wave measurements.
breathing after audible “beep” is heard Instruct patient to breath normally and then to momentarily stop
breathing during acquisition. When acquisition is complete, the system
freezes and emits one audible “beep”; resume normal breathing.
Obtain 5 measurements at same site Multiple measurements to ensure the median value is reliable.
Maintain an Interquartile Range (IQR) / Indicates variability of measurements lie within reasonable variability
Median ratio of ≤ 0.3 for values in range. It is the recommended quality control measure for adequate
kilopascals and ≤ 0.15 for values in technical quality. The IQR/Median ratio for elasticity in units of kPa will
meters per second be twice the IQR/Median ratio for shear wave velocity in units of m/s as
the conversion of m/s to kPa is nonlinear.
1
Barr, RG, et al. (2020), “Update to the Society of Radiologists in Ultrasound Liver Elastography Consensus Statement.”
Radiology, 00:1-12. doi.org/10.1148/radiol.2020192437. https://pubs.rsna.org/doi/10.1148/radiol.2020192437
siemens-healthineers.com/ultrasound 3
For the proper use of the software or hardware, please always use At Siemens Healthineers, our purpose is to enable healthcare
the Operator Manual or Instructions for Use (hereinafter collectively providers to increase value by empowering them on their journey
“Operator Manual”) issued by Siemens Healthineers. This material is towards expanding precision medicine, transforming care delivery,
to be used as training material only and shall by no means substitute and improving patient experience, all enabled by digitalizing
the Operator Manual. Any material used in this training will not be healthcare.
updated on a regular basis and does not necessarily reflect the latest
version of the software and hardware available at the time of the An estimated 5 million patients globally everyday benefit from our
training. The Operator Manual shall be used as your main reference, innovative technologies and services in the areas of diagnostic and
in particular for relevant safety information like warnings and therapeutic imaging, laboratory diagnostics and molecular medicine,
cautions. as well as digital health and enterprise services.
Note: Some functions shown in this material are optional and might We are a leading medical technology company with over 170 years
not be part of your system. of experience and 18,000 patents globally. With more than 48,000
dedicated colleagues in 75 countries, we will continue to innovate
Certain products, product related claims or functionalities described and shape the future of healthcare.
in the material (hereinafter collectively “Functionality”) may not
(yet) be commercially available in your country. Due to regulatory
requirements, the future availability of said functionalities in
any specific country is not guaranteed. Please contact your local
Siemens Healthineers sales representative for the most current
information. The reproduction, transmission or distribution of this
training or its contents is not permitted without express written
authority. Offenders will be liable for damages.
All names and data of patients, parameters and configuration
dependent designations are fictional and examples only. All rights,
including rights created by patent grant or registration of a utility
model or design, are reserved.
ACUSON Sequoia and Virtual Touch are trademarks of Siemens
Medical Solutions USA, Inc.
Siemens Healthineers Ultrasound owns the rights to all images.
Siemens Healthineers Headquarters Legal Manufacturer
Siemens Healthcare GmbH Siemens Medical Solutions USA, Inc.
Henkestr. 127 Ultrasound
91052 Erlangen, Germany 22010 S.E. 51st Street
Phone: +49 9131 84-0 Issaquah, WA 98029, USA
siemens-healthineers.com Phone: 1-888-826-9702
siemens-healthineers.com/ultrasound
Published by Siemens Medical Solutions USA, Inc. · HOOD05162003112648 · 8985 0820 online · © Siemens Medical Solutions USA, Inc., 2020
