ACUSON Sequoia 3.5 (VB30) Elastography Presentation

SIEMENS Healthineers .. ACUSON Sequoia Ultrasound System Virtual Touch Elastography Release 3.5 (VB30) Unrestricted © Siemens Healthineers 2024 Unrestricted Speaker Notes: No speaker notes. Notes No. 1 Objectives SIEMENS . Healthineers ... • Explain the basis of Virtual Touch technologies and tissue biomechanics • Demonstrate imaging controls and techniques for: • Strain imaging • Point shear wave (pSWE) • Auto point shear wave (Auto pSWE) • 2D shear wave (2D SWE) • Outline technology comparisons, clinical considerations and supporting clinical evidence for elastography exams 2 Unrestricted © Siemens Healthineers 2024 Speaker Notes: Upon successful completion of this presentation, you will be able to: • Explain Virtual Touch technologies and tissue biometrics • Demonstrate Strain imaging controls and techniques • Demonstrate 2D shear wave elastography controls and techniques in small parts and Musculoskeletal (MSK) applications • Demonstrate point shear wave (pSWE), Auto point shear wave (Auto pSWE) and 2D shear wave (2D SWE) elastography controls and techniques in liver applications • Outline technology comparisons, clinical considerations and supporting evidence for elastography exams Image: HOOD05162003330011 Notes No. 2 The next dimension of diagnostic information SIEMENS. Healthineers ... Additional information towards Anatomy clinical diagnosis and patient care B-mode Elastography Mechanical Doppler stiffness Vascular flow 3 Unrestricted © Siemens Healthineers 2024 Speaker Notes: Elastography provides a new dimension of diagnostic information to the ultrasound exam. With B-mode imaging, a diagnosis is based on the appearance of tissue in levels of gray and the presence of clinical markers, such as shadowing or enhancement. Doppler provides information on the presence or absence, speed and direction, of vascular flow. Elastography allows us to assess the mechanical stiffness of tissue, providing additional information towards the clinical diagnosis and care of the patient. Notes No. 3 Elastography provides information about the mechanical SIEMENS. Healthineers ... properties (stiffness) of tissue Hooke’s Law: No applied force Deformation is proportional to stiffness of material (𝐸) (object at rest) Force applied Where: Deformation is the relative change in shape or size of tissue after stressed And: L₀ L₁ Stress (𝜎)= Force/Area Strain (𝜖) = ∆ Length/Original Length 𝐿1 − 𝐿0 O- 𝜖 𝜖 = 𝐸 = 𝐿0 𝜎 4 Unrestricted © Siemens Healthineers 2024 Speaker Notes: To obtain information on mechanical properties or stiffness, the tissue needs to be deformed. Elastography uses the concept of Hooke’s Law to determine tissue stiffness. Hooke’s Law, or the law of elasticity, states that the strain in a solid is proportional to the applied stress within the elastic limit of that solid. In simpler terms, it means that the amount of deformation that occurs in an object when a force is applied is proportional to the stiffness of the object in question. Let’s take a closer look at this concept. The image on the right side of the slide shows two cylindric objects that represent biologic tissue. The first column, L0, is tissue “at rest” where there is no force applied. This column has a [resting] length of L0. If we take that same column of tissue and apply a known amount of force to it, the tissue will deform. This deformation results in a change in over length of the tissue; the new length is represented by L1. To determine the strain or deformation on the object, we then take both length values, L0 and L1, calculate the difference between the two values and divide that difference by the original length. The result is the amount of strain, or 𝜖 value, is then calculated. Once the amount of strain is determined we can then use that value divided by the known applied force to determine a quantitative stiffness level of the tissue (E). Note: Stress is the force you are applying normalized over the area over which you are pressing. Strain is how much deformation you are inducing in the object. Notes No. 4 Applied force and relative stiffness information SIEMENS. Healthineers ... • Pressure applied to soft objects (light gray circle) cause considerable deformation • Pressure applied to stiff/hard objects (black circle) have little or no deformation • The amount of deformation can be determined and depicted on an ultrasound image ACUSON ACUSON 10L4 10L4 No force applied Force applied 5 Unrestricted © Siemens Healthineers 2024 Speaker Notes: If we take Hooke’s Law and apply it to ultrasound, we can determine the stiffness of a lesion or mass within the tissues of the body using the transducer to apply force on an area or lesion. This example shows the 10L4 transducer at rest on the skin surface above two types of lesions. The black circle represents a hard mass, while the gray circle represents a softer lesion. When the user presses down on the tissue with the transducer, the force acts differently on the two lesions. The stiff black lesion shows little to no deformation, while the softer gray lesion has markedly deformed and compressed. Adding specialized elastography software to the mix will allow us to better see this deformation and visually highlight the stiffness level of each lesion in the resulting elastogram. Now let’s go over how we display this result as an elastogram during an ultrasound exam. Notes No. 5 Relative stiffness information on elastogram SIEMENS . Healthineers ... Hard tissue = less deformation Soft tissue = more deformation Grayscale or color-coded stiffness 6 Unrestricted © Siemens Healthineers 2024 Speaker Notes: Here we have a column of tissue elements that might appear identical on the B-mode image. When a stress is applied, the tissue elements can behave differently based on their stiffness level as we saw in the previous slide. The middle tissue element experiences almost no deformation because it is hard. The elements at the periphery of the column, however, experience more deformation because they are soft. Using the difference between the original and stressed image, the original image can now be labelled and displayed with stiffness information. We look to the grayscale or color bar that is displayed next to the image and, by convention, a dark shade is used to indicate stiff or hard tissue and lighter shades are used to indicate softer tissue. If a color map is selected, the color bar indicates which color represents soft or hard tissues. These gray or color shades are then used to assign and display the relative stiffness of tissue on the elastogram. Notes No. 6 Methods to deform tissue SIEMENS. Healthineers ... Manual compression • Manual compression is one way to deform tissue • Manual compression is traditionally known as Strain imaging • Compression is performed using the ultrasound transducer to push on the tissue surface • Deep structures are challenging to compress ACUSON 10L4 7 Unrestricted © Siemens Healthineers 2024 Speaker Notes: There are two ways to deform tissue in ultrasound using a transducer – manual and acoustic. Manual compression was the first type of strain we became familiar with in the field of ultrasound, and as such, manual compression has been traditionally described as Strain imaging. Using manual compression, stress is created by the user to an area or structure within the body by applying minimal compression with the transducer. While an effective technique, it can have a high degree of user variability. Additionally, it can be challenging to use this type of compression to generate enough stress on deeper tissue elements or structures that are located behind difficult to compress areas such as the rib cage. Notes No. 7 Methods to deform tissue SIEMENS. Healthineers ... Acoustic compression • Challenges of depth and user variability lead to using an acoustic wave to compress tissue • Acoustic Radiation Force Impulse (ARFI) was born out of this idea • ARFI uses a “push pulse” sent into the tissue by the Push pulse transducer to deform instead of manual compression Shear wave 8 Unrestricted © Siemens Healthineers 2024 Speaker Notes: This challenge of compression at depth and user variability led to development of the technology that is primarily used in ultrasound elastography today - Acoustic Radiation Force Impulse imaging, or ARFI. Unlike manual compression, ARFI uses an acoustic “push pulse” produced by the transducer to deform tissue. Using ARFI, we can now penetrate and strain deeper tissues than we could with a manual compression technique. Additionally, since the push is generated by the transducer, the user variability in amount of applied [manual] pressure is negated. Notes No. 8 Acoustic Radiation Force Impulse (ARFI) SIEMENS. Healthineers ... An introduction • A long duration push-pulse induces a small amount of displacement in the tissue • Ultrasound uses conventional transmits and signal processing (like Doppler) to monitor the displacement • With time, a shear wave propagates away from the push • The speed at which the shear wave propagates away is directly related to the stiffness of tissue 9 Unrestricted © Siemens Healthineers 2024 Speaker Notes: So, how does current ultrasound elastography – that is ARFI – work? To start, a long-duration transmit, or pushing-pulse, is initiated that induces a small amount of displacement in the tissue (approximately 10 microns or one one-hundredth of a millimeter). Ultrasound then uses conventional ultrasound transmits and signal processing similar to Doppler to monitor this displacement within the tissue. As time elapses after the push, a shear wave propagates away (perpendicular) from the pushes’ focus. Conceptually, this push and resulting shear wave can be compared to dropping a pebble into water and seeing the waves ripple out from the location of the pebble impact. In biological tissue, the speed at which the wave propagates away from the pushes’ focus (or impact point) is directly related to the stiffness of the tissue as described by continuum mechanics. Therefore, by estimating this shear wave speed in the tissue we obtain a quantitative estimate of the tissue stiffness. Notes No. 9 Viscoelasticity impact on estimated shear wave speed SIEMENS . Healthineers ... Viscoelastic tissue response • Shear wave elastography methods assume tissue is linear, elastic, homogeneous and isotropic • Viscoelasticity is the response of a solid to a force applied where the response is dependent on the rate at which the force is applied relative to its amplitude • Biological tissues are Viscoelastic, resulting in a frequency dependent shear wave • Shear wave speed increases with increased frequency of shear wave 10 Unrestricted © Siemens Healthineers 2024 Speaker Notes: Tissue make-up and ultrasound frequency do affect the resulting shear wave speed. Shear wave elastography methods typically assume that tissue is linear, elastic, homogenous and isotropic. However, this is not the case – in reality, most biological tissues are viscoelastic. Viscoelasticity is the continuum mechanics principle that describes the response of a solid to a force applied where the response is dependent on the rate at which the force is applied in addition to its amplitude. A real-world, everyday-life example of a viscoelastic material is a memory foam pillow or mattress. If you press in on the memory foam, it compresses relative to how hard you pressed (amplitude). When you release the memory foam, the original shape is slowly recovered, but at a different speed (rate) than when you originally compressed. Viscoelasticity is the material’s response to this combination of amplitude and rate dependent effects. Tissues that are viscoelastic result in a frequency dependent shear wave speed. Shear wave speed increases with increasing frequency, thus the higher the frequency at which the shear wave [exam] is performed, the higher the resulting shear wave speed. Notes No. 10 Virtual Touch applications SIEMENS . Healthineers .. ARFI + Manual Technology Shear Wave Compression Strain Point Shear Auto Point 2D Shear Application Strain Wave Shear Wave Wave Imaging Elastography Elastography Elastography (pSWE) (Auto pSWE) (SWE) Images 11 Unrestricted © Siemens Healthineers 2024 Speaker Notes: The ACUSON Sequoia ultrasound system has a comprehensive suite of Virtual Touch applications including Strain imaging, pSWE, Auto pSWE and SWE. Strain imaging uses manual compression to produce an elastogram image based on displacement of the tissue and relative tissue stiffness. pSWE, Auto pSWE and 2D SWE use ARFI to deform tissue and quantitative shear wave measurements can be made. Notes No. 11 Virtual Touch applications display SIEMENS . Healthineers ... Strain imaging pSWE and Auto pSWE 2D SWE O O Displacement correlation B-mode image Shear wave velocity image image Qualitative Quantitative Qualitative and Quantitative (Soft to hard scale) (Shear wave measurement) (Shear wave measurement scale) 12 Unrestricted © Siemens Healthineers 2024 Speaker Notes: Strain imaging creates a displacement correlation image, mapping relative stiffness, which can be qualitatively assessed. Notice that the gray or color bar next to the strain image indicates hard or soft and has no numerical values. pSWE displays only the B-mode image along with a shear wave measurement in units of m/s and kPa; hence, it can be quantitatively assessed. Auto pSWE uses the same shear wave technology but acquires up to 15 individual pSWE measurements at the same time. 2D SWE creates a color-coded shear wave velocity, or elasticity, image that can be both qualitatively and quantitatively assessed in units of m/s and kPa. Notes No. 12 ACUSON Sequoia ultrasound system SIEMENS . Healthineers ... Access VT Update 13 Unrestricted © Siemens Healthineers 2024 Speaker Notes: All technologies are available within the Virtual Touch elastography mode. To access the technologies, select the VT key on the Control Panel to activate the advanced application. Once activated, select a compatible transducer and exam preset to meet the needs of the anatomy exam. Notes No. 13 Virtual Touch application compatibility matrix SIEMENS. Healthineers ... Application/Transducer 5C1 DAX 4V1 9C2 10L4 14L5 15L4 18L6 9EC4 HLX Strain imaging Thyroid Thyroid Thyroid Thyroid Prostate Thyroid Breast Breast Breast Breast Breast MSK Testes Vascular Access Point Shear Wave Abdomen Abdomen Abdomen Abdomen Abdomen Elastography (pSWE) Auto Point Shear Wave Abdomen Abdomen Elastography (Auto pSWE) 2D Shear Wave Abdomen Abdomen Abdomen Thyroid Thyroid Thyroid Thyroid Elastography (2D SWE) Breast Breast Breast Breast MSK MSK Testes Vascular Access 14 Unrestricted © Siemens Healthineers 2024 Speaker Notes: All four applications have different transducers and exam preset availability. This matrix lists each technology, compatible transducers, and exam preset types. Notes No. 14 Objectives SIEMENS . Healthineers ... • Explain the basis of Virtual Touch technologies and tissue biomechanics • Demonstrate imaging controls and techniques for: • Strain imaging • Point shear wave (pSWE) • Auto point shear wave (Auto pSWE) • 2D shear wave (2D SWE) • Outline technology comparisons, clinical considerations and supporting clinical evidence for elastography exams 15 Unrestricted © Siemens Healthineers 2024 Speaker Notes: We will now discuss each individual technology beginning with strain imaging. Notes No. 15 Strain imaging SIEMENS. Healthineers ... Region of interest 14L5 Breast TIB:0.03 TIC 0.05 TIS:0.03 Transducer MI:0.66 15fps 95% dB/DR65 Strain Map 1 Soft Tissue Region of Stiff Lesion Interest 3cm QF: 81 16 Unrestricted © Siemens Healthineers 2024 Speaker Notes: Strain imaging provides a visual assessment of tissue stiffness and can, for example, allow a subtle lesion in soft tissue to be more clearly visualized and assessed. When a uniform stress is applied, each tissue type will deform differently. The resultant mapping of these different degrees of deformation clearly illustrates relative tissue stiffness. When Strain imaging is activated, the B-mode image will display side-by-side with the elastogram and the region of interest (ROI) box can be resized and repositioned over the desired area. Using real-time correlation methods, the system continuously estimates the degree of tissue deformation and displays the relative stiffness in either a gray scale or colorized elastogram. Notes No. 16 Strain imaging SIEMENS . Healthineers .. Relative stiffness Qualitative gray map 10L4 TIC 0.21 • Stiff lesion • Darker gray = harder than surrounding H High 3 DR65 Strain tissue Color 0 Map 0 Qualitative color map • Stiff lesion • Red = harder than surrounding tissue Teres DRES Map o 17 Unrestricted © Siemens Healthineers 2024 Speaker Notes: When using Strain imaging, it is important to understand what the gray shades and color shades indicate on the elastogram in terms of “relative stiffness”. The qualitative gray map and color map in these two images indicates that the lesion is stiffer, or harder, relative to the surrounding tissue. As shown in the image on the top, the gray bar located next to the image indicates that tissue displayed in darker gray shades are “harder” while lighter gray shades are “softer”. In the image on the bottom, the color bar located next to the image indicates that tissue displayed in redder colors are “harder” while pinker colors are “softer”. Notes No. 17 Strain imaging controls SIEMENS . Healthineers .. 5C ABLG 15L4 9C2 Workflow Patient 20 Virtual Touch Color Imaging Strain SWE 0 Review Report End Exam Color 1 Live Dual × Frequency Color Map Index Mid Color 2 18 Unrestricted © Siemens Healthineers 2024 Speaker Notes: Virtual Touch elastography mode will display the dedicated elastography applications that are available for the selected transducer and exam preset. Each application has its own dedicated tab folder containing the controls that can be used to perform the application. If needed, users select the Strain tab to activate Strain imaging and display its controls on the Touch Screen. When Strain imaging is activated, the B-mode image and elastogram display in a live, dual format as shown here in the image of a breast lesion. • If needed, the region of interest can be resized and repositioned over the area of interest • The image can be zoomed before or after acquisition • A color map can be selected to display the strain image in in soft pink to soft red shades or vibrant red to vibrant blue shades • The color maps are labelled 0 thru 2 and can be altered using the Color soft key on the Touch Screen menu • Three different Map Index settings are also available: 1 = Standard default map, 2 = Normalized map to compensate for non-uniform stress applied with the transducer and 3 = Inverted map • The key to select the Map Index is located on the Touch Screen soft keys as shown on this slide Notes No. 18 Strain imaging techniques SIEMENS . Healthineers ... • Position patient to obtain perpendicular plane to Avoid gray overlay box as shown here skin 10L4 Thyroid Minimal compression (use respirations or cardiac TIB:0.08 • TO:0.21 motion) TIS:0.08 1.15 6fps • Avoid lateral or rocking motion during acquisition 2D sigh • Quality Factor (QF) > 50 Strain Color • Optimize elastogram, then Freeze • Cine to obtain desired frames 3cm QF: 0 19 Unrestricted © Siemens Healthineers 2024 Speaker Notes: Use best practice techniques when performing Strain imaging for reliable and repeatable results. First, users optimize the scan direction by positioning the patient to obtain as much of a perpendicular plane to skin surface for good axial motion. Then, users apply minimal compression. In some cases, the natural compressions generated by a patient’s respirations and cardiac motion may be sufficient to generate the elastogram. If you see a gray overlay on the elastogram, as seen in this image of a thyroid lesion, it indicates one of the following conditions: too much lateral movement or rocking motion, too little pressure, or too much pressure, which causes the lesion to slip in and out of the plane. The system also displays a real-time Quality Factor score. Maintain a Quality Factor greater than 50 for optimal results. Optimize the elastogram and then press Freeze on the Control Panel. At this point, users review the cine buffer to obtain the desired frames and then choose a frame that contains several consecutive frames with the same Quality Factor score. Notes No. 19 Strain imaging techniques SIEMENS . Healthineers ... Effects of precompression 18L6 Breast TIB:0.06 Too much pressure substantially changes TIC:0.08 • H19: 0.06 elastography results -MI:0.47 1.5fps 95% 2D • Soft tissue can appear hard High 3dB/DR65 Strain Color 0 Map 0 • Minimize precompression by using minimal compression D=1.25 cm 3.5cm OF: 37 20 Unrestricted © Siemens Healthineers 2024 Speaker Notes: It is important to utilize proper scan technique to minimize the effect of precompression. If too much pressure is applied with the transducer, elastography results can substantially change. Fat can appear to have the same elasticity as cancer when too much pressure is applied. In this image of a breast mass, the soft tissue in the near field appears to show an increase in stiffness due to the effect of precompression. Also note that the quality factor is 37, indicating a less than optimal result. Precompression is a substantial factor in obtaining accurate results with elastography. Precompression should be minimized in obtaining clinical images.* *Barr, R. G. and Zhang, Z. (2012), “Effects of Precompression on Elasticity Imaging of the Breast.” Journal of Ultrasound in Medicine, 31: 895-902. doi:10.7863/jum.2012.31.6.895. Notes No. 20 Measurement options SIEMENS . Healthineers ... Shadow measurement Default Virtual Touch Exam Package 10LA Patient Right Left Shadow 95% Imaging 2D H High OdB/DR65 Review Mass 1 Mass 2 Mass 3 Report End Exam 1 D=0.51 cm O Ellipse ... Open Trace % EVE Ratio - D EINER Ratio - A Volume 3cm OF: 53 Clear Screen Last Caliper Hide Results 21 Unrestricted © Siemens Healthineers 2024 Speaker Notes: When the Shadow measurement is active, the system duplicates and displays the measurement on the adjacent image for a comparison of lesion size and/or location. Shadow calipers are often used with strain imaging. To perform a Shadow measurement, select Live Dual, if needed, and then press Caliper on the Control Panel to enter the measurement menu. Select Shadow on the Touch Screen to activate and measure either image. The measurement displays in the measurement display area, as shown here in the image of a thyroid lesion. Notes No. 21 Measurement options SIEMENS. Healthineers ... Strain ratio measurement Strain ratio = ROI 1/ROI 2 10L4 Breast TIB:0.05 TIC:0.17 TIS:0.05 • Place ROI 1 in tissue MI:1.20 15fps 95% 2D • Place ROI 2 in lesion (same size and at same H Mid dB/DR65 depth) Strain Color 0 Map 0 • Results: > 1 = Lesion is harder than the surrounding tissue • Results: 0 - 1 = Lesion is softer or the same as the surrounding tissue Strain Ratio=3.47 1 1 (Reference)=0. 111 % 2 ROI 2 (Mass)=0.032 % 4cm QF: 98 22 Unrestricted © Siemens Healthineers 2024 Speaker Notes: Strain ratio compares the relative stiffness of tissue within two ROIs. The strain ratio is the result of dividing ROI 1 by ROI 2. In this example, it has been used to compare the average strain of a breast lesion with the average strain of the surrounding tissue. When the first ROI is placed in the surrounding tissue and the second ROI is placed in the lesion, a strain ratio greater than 1 indicates that the lesion is harder than the surrounding tissue. A strain ratio less than or equal to 1 indicates that the lesion is softer or the same as the surrounding tissue. The strain ratio and the average strain percentage for both regions of interest are displayed in the measured results. In this image, the strain ratio of 3.47 indicates that the breast lesion is much harder than the surrounding tissue. The strain ratio and average strain (%) for both ROIs are displayed. Note: The first ROI is labeled ROI 1 (Reference) and the second ROI is labeled ROI 2 (Mass) to indicate placement location. Notes No. 22 Measurement options SIEMENS . Healthineers .. Elasticity imaging/B-mode (EI/B) ratio Exam rackaye 10L4 Default Virtual Touch Breast Breast TIB:0.05 TIC:0.17 Patient TIS:0.05 MI:1:20 Right Left Shadow 15fps Imaging 2D Review H Mid Mass 1 Mass 2 Mass 3 2dB/DR65 Strain Report Color 0 Map 0 End Exam × Distance O Open Tr. ELIB Ratio - A Volume El/B Distance Ratio=1.26 Clear Screen Edit Caliper Hide Results 1 8 3 2-34 cm [Select Cine 4cm QF: 98 23 Unrestricted © Siemens Healthineers 2024 Speaker Notes One of the most sensitive indicators for the likelihood of breast lesion malignancy is the ratio of the lesion size in the elastogram compared to the lesion size in the B-mode image. Research has shown that suspicious breast lesions appear measurably larger with elasticity imaging versus B-mode imaging. It is hypothesized that this is due to the detection of tentacle formation and/or desmoplasia, which is the growth of fibrous or connective tissue. When the ratio is >1, the probability of malignancy is increased.* In this example, the elasticity imaging to B-mode ratio diameter measurement has been used to compare the size of a breast lesion visualized in the elastogram with the size of a breast lesion visualized in the B-mode image. The ratio of the elastogram measurement divided by the B-mode measurement is displayed as 1.26 in the measured results, indicating that the lesion size is measuring larger in the elastogram then in the B-mode image. *Barr, R. G., De Silvestri, A. , Scotti, V. , Manzoni, F. , Rebuffi, C. , Capittini, C. and Tinelli, C. (2019), “Diagnostic Performance and Accuracy of the 3 Interpreting Methods of Breast Strain Elastography: A Systematic Review and Meta-analysis.” J Ultrasound Med, 38: 1397-1404. doi:10.1002/jum.14849. Notes No. 23 Common elastographic presentations SIEMENS . Healthineers .. “Bull’s-eye” appearance in cysts • Dark ring surrounding echogenic center 10L4 with posterior white spot Breast TIB:0.16 TIC:0.31 TIS:0.16 MI:1.17 15fps • Clinical marker for cysts 95% 2D H High dB/DR60 Applies to all organs opeed of Sound 2 • LD 1 UA 2 MapC/T4 P2 Strain • Occurs from decorrelation between images Color 0 Map 0 caused by fluid movement in cyst Scm OF : 91 24 Unrestricted © Siemens Healthineers 2024 Speaker Notes: A characteristic of Strain imaging is the “bull’s-eye” appearance in cysts. As shown in this image of a breast cyst, the “bull’s-eye” appears as a dark ring surrounding a bright, echogenic center, with a posterior white spot. It is a useful clinical marker for cysts in any organ imaged with Strain imaging. The bull’s-eye occurs from decorrelation between images caused by fluid movement in the cyst. Notes No. 24 Common elastographic presentations SIEMENS. Healthineers ... Solid, complex cyst or complicated cyst 18L6 Breast TIB:0.06 Lesion with internal echoes on B-mode image TIC:0.11 • TIS:0.06 MI:0.60 15fps 95% • Solid, complex cyst or complicated cyst 2D Mid 5dB/DR65 • Bull’s-eye appearance on elastogram Strain Color 0 Map 1 25 Unrestricted © Siemens Healthineers 2024 Speaker Notes: Complicated cysts contain low level internal echoes or internal debris which may produce an appearance like that of a solid mass or a complex cyst (containing both solid and cystic components). It is important to differentiate a complicated cyst from a complex cyst or a solid mass to best assess lesion management for follow-up, aspiration or biopsy. This slide shows how strain imaging can be used to support the differential diagnosis between a solid mass, a complex cyst or a complicated cyst. Notes No. 25 Common elastographic presentations SIEMENS . Healthineers ... Shadowing Shadowing displayed on B-mode image 10L4 • Difficult to distinguish or measure borders of lesion 2D H High • Shadowing does not affect the elastogram OdB/DR65 Strain Color 0 Map 0 • Borders and size can be more confidently determined Image Courtesy of Richard Barr, M.D., Ph.D., Radiology Consultants, Youngstown, OH 26 Unrestricted © Siemens Healthineers 2024 Speaker Notes: In this example, the B-mode image displays acoustic shadowing, characterized by the loss of signal around the lateral and posterior borders of a thyroid lesion due to strong absorption or reflection of the ultrasound waves. Shadowing makes it difficult to distinguish or measure the borders of this lesion. Notice how shadowing does not affect the elastogram. The borders of the lesion can be identified, and the size of the lesion can be determined with greater confidence. Notes No. 26 Objectives SIEMENS . Healthineers ... • Explain the basis of Virtual Touch technologies and tissue biomechanics • Demonstrate imaging controls and techniques for: • Strain imaging • Point shear wave (pSWE) • Auto point shear wave (Auto pSWE) • 2D shear wave (2D SWE) • Outline technology comparisons, clinical considerations and supporting clinical evidence for elastography exams 27 Unrestricted © Siemens Healthineers 2024 Speaker Notes: No speaker notes. Image: HOOD05162003330011 Notes No. 27 Point Shear Wave Elastography (pSWE) SIEMENS . Healthineers ... Multiple detection pulses Region of interest 9C2 Liver Site 1 Abdomen Push pulse Vs=1.04 m/s TIB:1.17 Push pulse E=3.2 kPa TIC:2.59 Depth=5.0 cm TIS:1.17 MI:1.22 63fps 95% 2D H Low 0dB/DR65 c=1540 LD 1 Shear Shear UA 2 MapD/T5 P2 waves waves PSWE Region of interest 28 Unrestricted © Siemens Healthineers 2024 Speaker Notes: pSWE applies multiple push pulses on both sides of the ROI producing shear waves that are propagated perpendicular to the push pulse throughout the tissue and in the ROI. Multiple detection pulses are sent through the ROI to monitor the speed of the shear wave. The speed correlates to the tissue stiffness. The quantitative result is instantly displayed next to the image in m/s and kPa along with the depth of the ROI. Notes No. 28 pSWE SIEMENS . Healthineers ... Correlation with the progression of liver stiffness The stiffer the tissue, the higher the pSWE measurement DAX Abdomen 5-3.2 kPO TIB:0.41 TIC:1.70 TIS:0.41 MI:1.38 18fps 95% 20 H Mid 0dB/DR60 PSWE Liver Site 1: 4 Voltar4 Y VS = 1.04 m/s V S = 1.47 m/s VS = 3.64 m/s 29 Unrestricted © Siemens Healthineers 2024 Speaker Notes: Liver assessment using gray scale ultrasound findings alone can be difficult. One of the reasons pSWE has become quite useful is the correlation between the progression of liver stiffness with quantitative tissue stiffness values. In these first two examples, the B-mode image is fairly similar overall but note how the shear wave measurements differ. In the third example, a small liver presents with ascites and a higher shear wave measurement value which, research reports, increases proportionally to the degree of liver stiffness. Image: HOOD05162003288405 Notes No. 29 pSWE SIEMENS. Healthineers ... Correlation with progression of liver stiffness* Radiology REVIEWS AND COMMENTARY . STATEMENTS AND GUIDELINES Update to the Society of Radiologists in Ultrasound Liver Elastography Consensus Statement Richard G. Barr, MD, PhD . Stephanie R. Wilson, MD . Deborah Rubens, MD . Guadalupe Garcia-Tsato, MD . Giovanna Ferraioli, MD From the Department of Radiology, Northeastern Ohio Medical University, Rootstown, Ohio (R.G.B.); Department of Radiology, University of Calgary, Calgary, Canada (S.R. W.); Departments of Imaging Science, Oncology, and Biomedical Engineering, University of Rochester Medical Center, Rochester, NY (D.R.); Section of Digestive Diseases, Department of Medicine, Yale University, New Haven, Conn (G.G.T.); and Ultrasound Unit, Department of Clinical Sciences and Infectious Diseases, Fondazi one IRCCS Policlinico San Matteo, University of Pavia, Pavia, Italy (G.F.). Received October 31, 2019; revision requested December 11; revision received April 2, 2020; accepted April 23. Address correspondence to R.G.B ., Southwoods Imaging, 7623 Market St, Youngstown, OH 44512 (e-mail: rgbam 525 @gmail.com). Conflicts of interest are listed at the end of this article. Radiology 2020, 00:1-12 . https://doi.org/10.1148/radiol.2020192437 . Content codes: GI JUS This multidisciplinary update of the Society of Radiologists in Ultrasound consensus statement on liver elastography incorporates the large volume of new information available in the literature since the initial publication. The recommended procedure for acquiring stiffness measurements is reviewed. There has been substantial improvement in the acoustic radiation force impulse (ARFI) technology-most notably the addition of a quality assessment of the shear wave propagation. Due to the efforts of the Quantitative Imaging Biomarkers Alliance, or QIBA, the variability of liver stiffness measurements between systems had decreased. There are now effective treatments for hepatitis B and hepatitis C, and follow-up after effective treatment should be based on the use of the delta change of the value obtained at viral eradication or suppression. Because the detection of compensated advanced chronic liver disease (cACLD) is very important, the new guidelines are made based on the probability of cACLD for given stiffness values. The panel recommends a vendor-neutral rule of four for interpretation for ARFI techniques. This new method simplifies interpretation of liver stiffness results and is more clinically relevant. @ RSNA, 2020 *Barr, RG, et al. (2021),“Update to the Society of Radiologists in Ultrasound Liver Elastography Consensus Statement.” Radiology, 00:1-12. doi.org/10.1148/radiol.2021192437. https://pubs.rsna.org/doi/10.1148/radiol.2021192437 30 Unrestricted © Siemens Healthineers 2024 Speaker Notes: The gold standard for diagnosing and monitoring the progression of liver fibrosis is liver biopsy. Yet there are known limitations of liver biopsy that make it less than ideal for ongoing assessment of disease progression (e.g., potential complications, availability and costs, intraobserver and interobserver variability and sampling error). The Update to the Society of Radiologists in Ultrasound Liver Elastography Consensus Statement, published in 2021, discusses the correlation between the progression of liver tissue stiffness and shear wave measurements.* Recommended protocols and procedures for acquiring stiffness measurements have been updated to reflect improvements in ARFI technology. *Barr, RG, et al. (2021),“Update to the Society of Radiologists in Ultrasound Liver Elastography Consensus Statement.” Radiology, 00:1-12. doi.org/10.1148/radiol.2021192437. https://pubs.rsna.org/doi/10.1148/radiol.2021192437 Notes No. 30 pSWE controls SIEMENS . Healthineers ... 5C1 SCT Abdomen 1816 15L4 ₼ 902 Workflow Liver Site 1 Abdomen 1 Vs 1.45 m/s TIB:1.17 E=6.3 kPa TIC:2.59 Depth=4.6 cm TIS:1.17 Patient 2D Virtual Touch MI:1.22 23fps 98% Imaging 2D PSWE / UDFF SWE H Mid 4dB/DR60 Review c=1540 PSWE Report PSWE UDFF End Exam Site Liver Segment Site 1 No Label Mass No Label X Compounding Liver Site 1: 4 Valid ( 4 Total Frequency 9cm Cooling 1 31 Unrestricted © Siemens Healthineers 2024 Speaker Notes: pSWE offers a highly reproducible technique using ARFI to correlate liver stiffness with shear wave quantification. When a compatible transducer and exam preset are selected, the pSWE tab will display in the Virtual Touch elastography mode and the pSWE ROI will display on the image. Site 1 is the default measurement label. If desired, select an alternate label. If No Label is selected, the measurements will appear next to the image but will not be sent to the report or added to the overall statistics. Roll the trackball to reposition the 2 cm cursor depth marker on the liver capsule to avoid subcapsular reverberation artifacts (artifactually induced area of increased stiffness) and to aid in reproducibility. Notes No. 31 pSWE acquisition SIEMENS . Healthineers ... 5C1 Liver Site 1 Abdomen 1 Vs 1.45 m/s TIB:1.17 E=6.3 kPa TIC.2 50 1 Update Depth=4.6 cm 23fps 98% x ... X 2D Caliper clip H Mid 4dB/DR60 c=1540 PSWE ABC 3 3 Image 2 Freeze 9cm Cooling 1 Liver Site 1: 4 Valid / 4 Total 4 Report 32 Unrestricted © Siemens Healthineers 2024 Speaker Notes: 1. To begin the acquisition, press Update on the Control Panel 2. When the acquisition is complete, the system automatically freezes (2), emits an audible “beep” and displays the shear wave measurement and ROI depth next to the image 3. To enter the measurement into the report, press Image to store the image or, press the right or left Set key. To make additional measurements, unfreeze the image and repeat the acquisition steps 4. Select Report located on the left side of the Touch Screen to view, delete, store, print, or transfer shear wave measurements Note: During freeze, a cooling timer indicates remaining seconds until the transducer is available for image acquisition. During a short cooling time (e.g., ~2 seconds depending on ROI depth), the timer appears and then disappears very quickly. Notes No. 32 Best practice techniques SIEMENS. Healthineers ... Patient preparation and positioning • Fast at least four hours • Supine or left lateral decubitus, right arm raised • Use ample gel 7 8 4a 2 • Transducer perpendicular to skin surface, maintain adequate contact 4b 3 • Intercostal approach, right lobe of liver 9 5 33 Unrestricted © Siemens Healthineers 2024 Speaker Notes: Use best practice techniques when performing point shear wave elastography for reliable and repeatable results. • In the non-fasting state, the liver can have falsely increased elastography values; therefore, the recommendation is to have the patient fast for at least four hours prior to the exam • Optimal patient positioning is supine or slight 30° left lateral decubitus with the right arm elevated above the head to improve intercostal access • Use ample gel so that the transducer surface is in continuous contact with the skin surface • In general, use a transducer angle of 90° to the skin surface for the highest measurement accuracy. An out-of-plane transducer angle less than 50° to the skin surface can result in artificially low shear wave measurements due to the loss of transducer contact with the flat scanning surface • To obtain reproducible results in the liver and to avoid cardiac motion, take measurements in the right lobe of the liver in either segment 5 or 8, using an intercostal scanning approach Notes No. 33 Best practice techniques SIEMENS . Healthineers .. Liver assessment • Place the ROI perpendicular to the liver capsule • Position the 2 cm cursor depth marker on the liver capsule • Image parallel to ribs with bright liver parenchyma • Avoid large vessels, bile ducts and rib shadows Aber Site 1: @ Valid / 1 Total Poor pSWE Technique Better pSWE Technique 34 Unrestricted © Siemens Healthineers 2024 Speaker Notes: Use best practice techniques when placing the measurement ROI for reliable and repeatable results. Avoid increased subcapsular reverberation artifacts by placing the ROI perpendicular to, and at least 1.5 to 2 cm below, the liver capsule. This can be achieved by placing the 2 cm cursor depth marker on the liver capsule, aiding in reproducibility. Scan parallel to the ribs in an intercostal space to avoid rib shadow artifacts. Optimize the B-mode image so that the liver parenchyma is bright and large vessels, bile ducts and rib shadows are avoided. As shown here, the image on the left displays poor technique and invalid measurements due to poor propagation of the push pulse through the ribs. In addition, the cursor is angled and the ROI is too close to the liver capsule. The image on the right displays proper technique and valid measurements. Notes No. 34 Best practice techniques SIEMENS . Healthineers ... Liver assessment • Perform acquisition during suspended respiration Liver Site 1 Abdomen 1 Vs=1.39 m/s TIB:1.17 TIC:2.59 Patient may breathe after audible “beep” is heard E=5.8 kPa • Depth=4.6 cm TIS:1.17 MI:1.22 23fps 98% • Obtain 10 measurements at same site; fewer can 2D H Mid be made (at least five)* 4dB/DR60 c=1540 PSWE • Maintain IQR/Median ratio of ≤ 0.3 for values in kPa and ≤ 0.15 for values in m/s* 9cm Cooling 0 Liver Site 1: 10 Valid / 10 Total *Barr, RG, et al. (2021),“Update to the Society of Radiologists in Ultrasound Liver Elastography Consensus Statement.” Radiology, 00:1-12. doi.org/10.1148/radiol.2021192437. https://pubs.rsna.org/doi/10.1148/radiol.2021192437 35 Unrestricted © Siemens Healthineers 2024 Speaker Notes: When taking measurements, advise the patient to breathe normally and then to momentarily pause breathing during acquisition. Avoid taking measurements during Valsalva or deep inspiration and breath hold to avoid an undesired increase in central venous pressure. Elevated central venous pressure can falsely elevate shear wave measurements. When the acquisition is complete, the system automatically emits one audible “beep”. The patient may resume normal breathing when the audible “beep” is heard. At least 10 measurements should be taken in the same location to aid in measurement repeatability with the median shear wave measurement value representing the most reliable single measure when there are measurement outliers. Fewer than 10 measurements can be made (at least five); however, the IQR/Median ratio should be within the recommended range. Maintain an IQR/Median ratio of ≤ 0.3 for values in kPa and ≤ 0.15 for values in m/s for adequate technical quality and to ensure that the variability of measurements lies within a reasonable variability range.* Note: The IQR/Median ratio for elasticity in units of kPa will 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. Notes No. 35 pSWE measurements SIEMENS . Healthineers ... Liver assessment If X.XX value is displayed: 5C1 Liver Site 1 Abdomen Low shear wave signal-to-noise ratio 1 Vs=X.XX TIB:0.88 E=XX.X TIC:2.20 • Depth=4.0 cm TIS:0.88 MI:1.39 24fps • Proximity of ROI to a rib shadow (poor 98% 2D technique) H Mid 3dB/DR60 c= 1540 • Measurements exceed the maximum PSWE displayable value • Excessive motion, such as liver tissue movement 11cm Liver Site 1: 0 Valid / 1 Total 36 Unrestricted © Siemens Healthineers 2024 Speaker Notes: If the system displays the shear wave measurement as an invalid “X” value, the confidence interval threshold for measurement quality was not reached. You will need to repeat the acquisition until the system displays a numerical value. Most commonly, this results from a low shear wave signal-to-noise ratio due to either a high tissue stiffness, a large patient body habitus or a thick sono-opaque adipose layer. The push pulse cannot generate enough shear wave magnitude and is grossly attenuated. Invalid “X” values can also be caused by the proximity of the ROI to a rib shadow, due to poor technique. It can also display if the measurements exceed the current maximum displayable value. Excessive motion in the tissue that disrupts the shear wave measurement estimate may also produce invalid results. Notes No. 36 pSWE liver assessment report SIEMENS . Healthineers .. Liver Site 1 • Valid result: Interquartile Range (IQR)/Median Vs E Depth ratio of ≤ 0.3 for values in kPa and ≤ 0.15 for m/s kPa cm values in m/s* 5.0 4.7 1.26 4.8 4.7 1.52 6.9 4.7 • The recommended quality control measure for 1.36 5.6 4.7 adequate technical quality* 1.28 4.9 4.7 1.37 5.7 4.7 1.34 5.3 1.37 5.6 1.24 4.6 1.81 9.9 81000 VOUIAWN - Mean 1.39 5.8 Std Dev 0.17 1.6 Median 1.35 5.4 D -0.00 IQR/Median 0.07 0.1 Overall Statistics Mean 1.39 m/s Std Dev 0.17 m/s Median 1.35 m/s IQR 0.09 m/s IQR/Median 0.07 Mean 5.8 kPa Std Dev 1.6 kPa Median 5.4 kPa IQR 0.8 kPa IQR/Median 0.1 Note: Shear Wave Speed and Elasticity values may vary among manufacturers! *Barr, RG, et al. (2021),“Update to the Society of Radiologists in Ultrasound Liver Elastography Consensus Statement.” Radiology, 00:1-12. doi.org/10.1148/radiol.2021192437. https://pubs.rsna.org/doi/10.1148/radiol.2021192437 37 Unrestricted © Siemens Healthineers 2024 Speaker Notes: Displayed here is the liver assessment report containing each of the measurements along with the statistical data in units of m/s and kPa. The report includes the Interquartile Range (IQR), which is the range of the spread of values in a repeated data set, from the 25th to 75th percentile. It is sometimes referred to as the “middle fifty”. It removes outlying measurements to more accurately represent the spread of values in a data set. The median shear wave value is used with the IQR to calculate the Interquartile Range to Median (IQR/Median) ratio. An IQR/Median ratio of ≤ 0.3 for values in kPa and ≤ 0.15 for values in m/s indicates that the variability of measurements lies within a reasonable variability range. It is the recommended quality control measure for adequate technical quality. A higher ratio indicates significant variability in the shear wave measurements, decreasing the reliability of measurement results. The IQR will be higher with advancing fibrosis; since the IQR/Median ratio normalizes for this increase, it is an important indicator of technical accuracy. Note: The IQR/Median ratio for elasticity in units of kPa will 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. Absolute values for shear wave measurements may vary among different manufacturers due to multiple system-dependent factors, including shear wave frequency, excitation beam (push beam) frequency, shear wave detection techniques, and shear wave measurement estimation methods. Notes No. 37 Objectives SIEMENS . Healthineers ... • Explain the basis of Virtual Touch technologies and tissue biomechanics • Demonstrate imaging controls and techniques for: • Strain imaging • Point shear wave (pSWE) • Auto point shear wave (Auto pSWE) • 2D shear wave (2D SWE) • Outline technology comparisons, clinical considerations and supporting clinical evidence for elastography exams 38 Unrestricted © Siemens Healthineers 2024 Speaker Notes: No speaker notes. Image: HOOD05162003330011 Notes No. 38 Auto pSWE – 9C2 SIEMENS . Healthineers .. • Acquires up to 12 individual pSWE measurements Liver Site 1 Abdomen in a single acquisition Vs Median=1.10 m/s TIB:1.05 E Median=3.6 kPa TIC:2.05 Depth=4.2 cm TIS:1.05 MI:1.29 • Automatically removes any invalid measurements 53fps 2D • Dots visually indicate stiffness value in each sub- H Low -2dB/DR65 ROI c=1540 LD 1 UA 2 MapD/T5 P2 PSWE 8cm 39 Unrestricted © Siemens Healthineers 2024 Speaker Notes: Auto pSWE is a workflow enhancement available on the 9C2 and DAX transducers. It allows the user to acquire up to 15 individual pSWE measurements with a single acquisition on DAX and up to 12 individual pSWE measurements on the 9C2. On the 9C2, a large ROI is divided into 12 individual sub-ROIs that are equal in sample size to an individually acquired pSWE ROI. The large ROI is placed within the right lobe of the liver following the same technique as a single pSWE acquisition ROI. A “grid” of up to the 12 sub- ROIs only appears once the acquisition has been completed. Any invalid measurements are removed from the overall total and the sub-ROI is not displayed within the grid. The results for each sub-ROI are displayed on the left panel of the imaging screen and in the patient report. Each valid sub-ROI also contains up to four dots that indicate the level of stiffness contained in that specific sample area. The dots are only a visual cue to be used as a quick reference and aid workflow – the precise value of the sub-ROI can be found in the report or onscreen display. Here is an example of the ROI display grid using Auto pSWE on the 9C2. Notes No. 39 Auto pSWE – DAX SIEMENS . Healthineers ... • Acquires up to 15 individual pSWE DAX measurements in a single acquisition Liver Site 2 Abdomen Vs Median=1.19 m/s TIB:0.91 E Median=4.2 kPa TIC:2.48 • Automatically removes any invalid UDFF=5 % TIS:0.91 Depth=5.6 cm MI:1.38 measurements 19fps 95% 2D Dots visually indicate stiffness value in each H Low • 0dB/DR60 sub-ROI c=1540 PSWE 17cm Cooling 11 40 Unrestricted © Siemens Healthineers 2024 Speaker Notes: Here is an example of the ROI grid using Auto pSWE on the DAX. On the DAX, a large ROI is divided into 15 individual sub-ROIs that are equal in sample size to an individually acquired pSWE ROI. The large ROI is placed within the right lobe of the liver following the same technique as a single pSWE acquisition ROI. A “grid” of up to the 15 sub- ROIs only appears once the acquisition has been completed. Any invalid measurements are removed from the overall total and the sub-ROI is not displayed within the grid. Notes No. 40 Auto pSWE acquisition pattern SIEMENS. Healthineers ... • Push pulse is focused on a specific sub-ROI during acquisition • Displays median values for Vs and E in MDA • Summary of all measurements is displayed onscreen in left panel DAX • Available on DAX and 9C2 • Can be used at the same time with Ultrasound Derived Fat Fraction (UDFF) 41 Unrestricted © Siemens Healthineers 2024 Speaker Notes: Auto pSWE using the same push pulse and detection pulse technology to obtain multiple (up to 15) shear wave measurements in a single instance. Auto pSWE acquires each of the 12 or 15 measurement values in a specific pattern with the push pulse being focused on the individual sub-ROI it is measuring. The [up to] 15 measurements happen very quickly and begin in the lower left corner and travel from bottom to top and left to right across the entire ROI. The last sub-ROI sampled is in the upper right corner of the large ROI. Once the last sub-ROI has been measured, a grid of all valid measurements and associated stiffness dot(s) will appear within the large ROI. Any values that are not valid will not display a square and dots within the sub-ROI. The measurement display area (MDA) will display the median values for velocity (Vs) and elasticity (E) of all valid measurements (up to 15). The Auto pSWE option is currently available on the 9C2 and the deep abdominal (DAX) transducers in the Abdomen exam preset. Additionally, Auto pSWE can be used simultaneously with the Ultrasound Derived Fat Fraction (UDFF) measurement. While inherently different technologies, Auto pSWE uses the same overall ROI as UDFF measurement. When used together, both the liver stiffness values and the fat fraction value will be displayed in the MDA when the acquisition is complete. Note that using Auto pSWE in conjunction with UDFF will increase the cooling time. For more information on UDFF please refer to the dedicated UDFF educational materials. Notes No. 41 Auto pSWE measurement order SIEMENS. Healthineers ... • Measurement display order differs from acquisition order • Display is from left to right, in rows, moving down DAX the image • Important to know for correlation of individual sub-ROIs 1 5 6 10 11 ----- 15 42 Unrestricted © Siemens Healthineers 2024 Speaker Notes: The measurement display order for Auto pSWE differs from the measurement acquisition order. As we saw in the previous slide, the acquisition order is done in columns beginning in the lower left corner of the same sample box and concluding in the right upper corner. The measurements are displayed and thus numbered, from left to right in rows, moving down the image. Measurement “number 1” is associated with the sub-ROI in the top left corner of the grid whereas measurement “number 15” would correspond to the sub-ROI in the lower right corner of the grid. This layout is important to know and understand when correlating individual sub-ROIs with the overall list of posted stiffness results. Same order goes for the 9C2, 1-4, 5-8 and 9-12 from top to bottom, respectively. Notes No. 42 Auto pSWE controls SIEMENS. Healthineers ... • Auto pSWE key located in the Virtual 1816 15L4 ₱ Abdome Workflow Touch tab > pSWE option on the Touch Screen Patient 2D Virtual Touch BuiBewy PSWE / UDF SWE • Default active measurement label is Review Site 1 Report PSWE UDFF uto PSWE Select the Auto pSWE control to End Exam • Site Liver Segment Mass activate the feature Site 1 No Label No Label Compounding X 6 Frequency H Mid 43 Unrestricted © Siemens Healthineers 2024 Speaker Notes: The Auto pSWE key is located on the Touch Screen within the Virtual Touch pSWE tab next to the UDFF key. When the Auto pSWE key is activated, the Site 1 measurement label will automatically be selected. Acquiring an Auto pSWE measurement follows the same best practice technique as an individual pSWE acquisition. Notes No. 43 Auto pSWE image layout SIEMENS . Healthineers .. MDA displays in Liver capsule marker DAX both m/s and kPa Liver Site 1 Abdomen Vs Median=1.20 m/s TIB:0.90 E Median=4.4 kPa TIC:2.47 Depth=5.6 cm TIS:0.90 MI:1.38 19fps 95% 2D H Low 0dB/DR60 12 or 15 sub-ROI’s c=1540 PSWE Dot Values # Dots Stiffness 1 < 5 kPa 2 5-9 kPa 3 9-13 kPa 17cm Cooling 12 4 > 13 kPa 44 Unrestricted © Siemens Healthineers 2024 Speaker Notes: This image depicts an Auto pSWE acquisition in which all 15 sub-ROIs are considered valid. The MDA displays the measurement depth and median values for velocity (Vs) and elasticity (E.) Each individual pSWE value will be displayed in the left panel on the imaging screen and in the report. These displays will be covered later in this presentation. The dots contained within each valid sub-ROI are a visual representation to the user of the level of stiffness within a given sub-ROI. The dot values are not displayed on the system or in the report – they are only to be used as a workflow aid. It is not necessary to memorize the values of the dots listed on this slide, but rather remember that the greater the number of dots the greater the stiffness value will be for that sub-ROI. Notes No. 44 Auto pSWE image layout – 9C2 SIEMENS . Healthineers ... ▪ ROI Size: 2.5cm x 2.0cm Liver Site 3 9C2 Vs Median=1.20 m/s Abdomen TIB:1.05 ▪ Sub-ROI Size (Acquisition): 1.0cm x .75cm E Median=4.4 kPa UDFF=8 % TIC:2.04 Depth=5.6 cm TIS:1.05 MI:1.29 88fps ▪ Sub-ROI Size (Displayed): .833cm x .5cm 95% 2D H Mid -5dB/DR65 c=1540 LD 1 UA 2 MapD/T5 PSWE 45 Unrestricted © Siemens Healthineers 2024 Speaker Notes: On the 9C2, the acquisition size of each sub-ROI is 1.0 x 0.75 cm. While the grid depicts a side- by-side layout, there is overlap between each sub-ROI during the acquisition. The size displayed on the screen (“display size”) for each sub-ROI within the overall grid is 0.83 x 0.5 cm. This difference in size is only visual so all 12 sub-ROIs will fit within the 2.5 x 2.0 cm ROI. Notes No. 45 Auto pSWE image layout – DAX SIEMENS. Healthineers ... ▪ ROI Size: 3.0cm x 3.0cm DAX Abdomen Liver Site 3 TIB:0.90 ▪ Sub-ROI Size (Acquisition): 1.5cm x 1.0cm Vs Median=1.20 m/s TIC:2.47 E Median=4.4 kPa TIS:0.90 UDFF=8 % MI:1.38 Depth=5.6 cm ▪ Sub-ROI Size (Displayed): 1.0cm x .75cm 95% 2D H Low 0dB/DR60 c=1540 PSWE 17cm Cooling 12 46 Unrestricted © Siemens Healthineers 2024 Speaker Notes: On the DAX, the acquisition size of each sub-ROI on DAX is 1.5 x 1.0 cm. While the grid depicts a side-by-side layout, there is overlap between each sub-ROI during the acquisition. The size displayed on the screen (“display size”) for each sub-ROI within the overall grid is 1.0 x 0.75 cm. This difference in size is only visual so all 15 sub-ROIs will fit within the 3 x 3 cm ROI. Notes No. 46 Auto pSWE “invalid” ROIs SIEMENS . Healthineers .. DAX Liver Site 2 Abdomen Vs Median=0.77 m/s TIB:0.91 E Median=1.8 kPa TIC:2.49 Depth=5.6 cm TIS:0.91 MI:1.38 18fps 95% 2D H Low Sub-ROI will not 0dB/DR60 c=1540 display if PSWE measurement is invalid 18cm Cooling 11 47 Unrestricted © Siemens Healthineers 2024 Speaker Notes: Unlike conventional pSWE where a single measurement is taken and the MDA displays the “X.XX” value in the MDA if invalid, Auto pSWE acts a little different. Since Auto pSWE obtains multiple measurements in a single acquisition, the chances of having the entire sample be invalid is extremely small. If a sub-ROI value is considered invalid by the ultrasound system (i.e. due to an artifact) it is not displayed within the resulting acquisition grid. The value is not used for any calculations and will not be displayed in the left panel or within the patient report. The sub-ROI contained in that area will be blank. The MDA will still display the median values for velocity and elasticity for all valid measurements. Notes No. 47 Auto pSWE and UDFF SIEMENS . Healthineers .. DAX Measurement Liver Site 3 Abdomen TIB:0.90 display area Vs Median=1.20 m/s E Median=4.4 kPa TIC:2.47 UDFF=8 % TIS:0.90 shows both Depth=5.6 cm MI:1.38 19fps values 95% 2D H Low 0dB/DR60 c=1540 PSWE Auto pSWE and UDFF measurements calculated within the same area 17cm Cooling 12 48 Unrestricted © Siemens Healthineers 2024 Speaker Notes: As noted earlier, Auto pSWE can be used simultaneously with UDFF to generate both values. While the two technologies use different technologies to calculate their respective values, the overall ROI used is the same. Visually, the only indicator on the imaging screen that both technologies are engaged is through the MDA, which will display the values related to both technologies. Combining the two technologies is a workflow advantage, as it allows the user to perform two advanced complementary applications at one time, as from a clinical standpoint, [high] fat content within the liver is related to an increase in liver tissue stiffness. The ability to obtain both stiffness and fat fraction values simultaneously negates the need for the user to perform an additional exam based on the individual results of either a pSWE or UDFF exam. Notes No. 48 Auto pSWE onscreen results display SIEMENS . Healthineers ... • If a label is used, results will display on the left panel and in the report Frozen PSWE Measurements Liver 5hte 1 . • Only median Vs and E values will be Liver Säu 1 Vs Median=1.07 m/s E Median=3.4 kPa Depth=5.4 cm displayed in the MDA onscreen if no label is 1.21 75 1.46 2.9 used 1.21 44 DEB/DR60 1.30 DOWE 1.04 1.07 3.4 0.99 3.0 10.83 2.1 • UDFF values will not be displayed in the left 0.99 29 1.23 4.6 1.00 panel but will display in the measurement 15 25 display area and patient report 1.13 15 1.07 Dvesall Statistics - Liver 1.13 4.0 1.07 3.4 10.24 16.18 49 Unrestricted © Siemens Healthineers 2024 Speaker Notes: The median value for Vs and E for the acquired sub-ROI measurements will be displayed on the image screen within the MDA. To aid in workflow, each individual pSWE result will be displayed in the left panel of the imaging screen once the acquisition has been completed and/or the Set key is pressed. This display negates the need to open the patient report page to view the individual values. The statistical values for the multi-acquisition will also be displayed including the IQR/median in both m/s and kPa. Note that Auto pSWE measurements can also be obtained without using a measurement label. If no measurement label is selected, only the Vs median and E median will be displayed in the MDA – there will be no individual pSWE measurements for each sub-ROI displayed in the left panel. If UDFF is used in conjunction with Auto pSWE, the UDFF measurements will only be displayed within the MDA and the patient report – they will not appear in the left measurement panel outlined in orange above. Notes No. 49 Auto pSWE liver assessment report SIEMENS . Healthineers .. • Valid result: Interquartile Range (IQR)/Median ratio of ≤ 0.6 for values in kPa and ≤ 0.3 for values Liver Site 1 Vs E Depth in m/s* m/s kPa cm 1.28 4.9 4.4 1.09 3.5 4.4 The recommended quality control measure for 1.13 3.8 4.4 • 1.17 4.1 4.4 adequate technical quality* 1.03 3.2 4.4 1.17 4.1 4.4 1.12 3.8 4.4 1.07 3.4 4.4 Shear wave values may vary note on report page 1.04 3.2 4.4 • 1.01 3.1 4.4 1.12 3.8 4.4 1.06 3.4 4.4 0.98 2.9 4.4 1.05 3.3 4.4 1.04 3.2 4.4 GEWNESONOQUIOWN- Mean 1.09 3.6 Std Dev 0.08 0.5 Median 1.07 3.4 0.09 0.6 IOR/Median 0.08 0.18 Overall Statistics Mean 1.09 m/s Std Dev 0.08 m/s Median 1.07 m/s IQR 0.09 m/s IQR/Median 0.08 Mean 3.6 kPa Std Dev 0.5 kPa Median 3.4 kPa IQR 0.6 kPa IQR/Median 0.18 *Barr, RG, et al. (2021),“Update to the Society of Radiologists in Ultrasound Liver Elastography Consensus Statement.” Radiology, 00:1-12. doi.org/10.1148/radiol.2021192437. https://pubs.rsna.org/doi/10.1148/radiol.2021192437 50 Unrestricted © Siemens Healthineers 2024 Speaker Notes: Displayed here is the liver assessment report for Auto pSWE. Note that it only differs from a conventional pSWE report on the number of samples listed. The Auto pSWE report contains the same statistical aspects and the results are garnered by the same metrics as conventional pSWE. Notes No. 50 Best practice techniques Auto pSWE SIEMENS. Healthineers ... Liver assessment • Place the ROI perpendicular to the liver capsule Poor Technique Good Technique • Position the 2 cm cursor depth marker on the liver capsule • Image parallel to ribs with bright liver parenchyma DAX • Avoid large vessels, bile ducts and rib shadows X DAX L 51 Unrestricted © Siemens Healthineers 2024 Speaker Notes: Follow the same best practice techniques when performing an Auto pSWE measurement as you would for conventional (individual) pSWE acquisitions by: 1. Ensuring the marker is parallel to the liver capsule 2. The ROI is at least 1.5 to 2 cm deep 3. Avoid any large vessels, ducts, or rib shadows within the ROI Notes No. 51 Objectives SIEMENS . Healthineers ... • Explain the basis of Virtual Touch technologies and tissue biomechanics • Demonstrate imaging controls and techniques for: • Strain imaging • Point shear wave (pSWE) • Auto point shear wave (Auto pSWE) • 2D shear wave (2D SWE) • Outline technology comparisons, clinical considerations and supporting clinical evidence for elastography exams 52 Unrestricted © Siemens Healthineers 2024 Speaker Notes: Next, lets review 2D shear wave elastography. Image: HOOD05162003330011 Notes No. 52 2D SWE SIEMENS . Healthineers' ... Push pulse 2D SWE region of interest Shear Shear waves waves Detection Detection O SWE pulses pulses Geschwindigkei Transparenz. 60% 1 Gs Median=1,54 m/s E Median=7,1 kPa Tiefe=1,99 cm 2D SWE Diam=0,30 cm 2D Shear Wave Elastography (SVE) Velocity Map Image courtesy of Martin Daniatar, M.D. University of lanstuck, Austr region of Measurement region interest of interest 53 Unrestricted © Siemens Healthineers 2024 Speaker Notes: 2D SWE applies high density push pulses sequentially across the ROI resulting in shear wave propagation across the ROI. A series of ultrasound detection pulses follow in a quick push pulse, detect pulse, push pulse sequence. Shear wave speed estimates are then calculated for each pixel with exceptional color-coded resolution. Measurement ROIs can then be placed at precise locations to measure tissue stiffness in m/s and kPa. Notes No. 53 2D SWE controls SIEMENS . Healthineers ... ›SC1 18L6 15L4 Abdomen Workflow Patient 2D Virtual Touch 1 Imaging PSWE / UDFF SWE Update Review Report End Exam Quality 4 ABC m/s 5 Live Dual X Freeze Transparency 60% + Compounding 2 Frequency Min Veloci 3 Max Velocity Min Elasticity Max Elasticity H Mid 0.5 50 54 Unrestricted © Siemens Healthineers 2024 Speaker Notes: 2D SWE is activated by selecting the SWE tab. A full-screen or live dual format can be displayed, and the ROI can be repositioned and resized over the area of interest. 1. To begin the acquisition, press the Update key on the Control Panel. 2. When the acquisition is complete, the system automatically freezes, emits an audible “beep” and applies the display mode in the ROI. 3. The minimum and maximum velocity or elasticity scale can be altered by using the rotary keys on the Control Panel. 4. If Elasticity is the desired parameter/unit, then select the option from the available display modes. 5. Transparency is available and located on the Touch Screen. Note: Unless both Elasticity and Velocity are selected for the dual display options, only the chosen display option (Elasticity or Velocity) will be active and adjustable on the Touch Screen denoted by (3) on this slide. Note: During freeze, a cooling timer indicates the remaining time (in seconds) until the transducer is available for image acquisition. During a short cooling time (e.g., 1-2 seconds), the timer appears and then disappears very quickly. Notes No. 54 2D SWE Touch Screen controls SIEMENS. Healthineers .. 10L4 10L4 Thyroid TIB:0.47 Thyroid TIB:0.47 TIC:0.71 TIC:0.71 TIS:0.47 TIS:0.47 MI:1.37 42fps MI:1.37 42fps 95% 95% 2D odB/DR65 OdB/DR65 SWE Velocity Transp: 60% Velocity Transp: 60% Min Velocity Max Velocity Min Velocity Max Velocity 0.5 7.5 0.5 4 55 Unrestricted © Siemens Healthineers 2024 Speaker Notes: The measurement range of the ROI can be adjusted by rotating the Min or Max Velocity/Elasticity soft key controls (Note: display of velocity or elasticity option is dependent on mode). The system updates the shear wave display in the ROI and on the color bar to depict the selected range. If needed, the range can be decreased for better visualization of stiffness differences. The range can be increased if the measured value exceeds the range and displays “High” in the measurement display area. The Max Velocity has been decreased from 7.5 to 4.0 in these two images as displayed on the color bar. Notice the improvement in visualization of stiffness variability in the image of a thyroid lesion on the right. Notes No. 55 2D SWE display modes SIEMENS . Healthineers ... • Velocity or Elasticity - higher in hard tissue and lower in soft tissue • Quality - green indicates high confidence in measurement accuracy • Displacement - higher in soft tissue and lower in hard tissue Velocity Quality Displacement 56 Unrestricted © Siemens Healthineers 2024 Speaker Notes: There are three shear wave display modes for 2D SWE. Each of these modes provides additional information for evaluating and interpreting the 2D SWE image. The first display mode, as shown in the image on the left, is a color-coded display of shear wave values in Velocity or Elasticity. Refer to the color bar to determine which colors indicate higher values and which colors indicate lower values. Shear wave values are lower in soft tissue and higher in stiff tissue. The second display mode, as shown in the image in the middle, is the Quality map. The Quality map differentiates where the shear wave measurement estimate is accurate and where it is poor. Refer to the color bar next to the image to determine which colors represent high quality or low quality areas. Measurements should only be taken in regions with high quality (green to yellow-green). The third display mode, as shown in the image on the right, is the Displacement map. The Displacement map indicates the relative stiffness in tissue, similar to a Strain image, but without the need for manual compression. Refer to the color bar next to the image to determine which colors represent higher tissue displacement and which colors represent lower tissue displacement. Displacement is higher in soft tissue and lower in hard tissue. Correlate the areas in the Velocity or Elasticity image with the shear wave signal-to-noise ratio and the Displacement amplitude. The Displacement map may also help to improve visualization of lesion boundaries. Notes No. 56 2D SWE Displacement maps SIEMENS . Healthineers ... Two map choices for Displacement – black and white or a blue map Displacement Velocity Displacement Velocity Black and white Blue 57 Unrestricted © Siemens Healthineers 2024 Speaker Notes: There are two options for viewing the Displacement map of the elastogram – a black and white map or a blue map. Each map displays the same information. A customized preset can be created to reflect the user’s viewing preference. Notes No. 57 2D SWE Dual Map display SIEMENS. Healthineers ... • Map display can be changed to any combination and/or Quality Velocity units • Select Live Dual > toggle to desired side > used Touch Screen options to select map type Quality Velocity m/s Velocity Quality Displacement Displacement 2D Only Live Dual kPa Quality • Last used is remembered for transducer and can be saved as preset 58 Unrestricted © Siemens Healthineers 2024 Speaker Notes: The Dual Map Display allows the user to view two different maps side-by-side. The maps that are displayed can be customized by toggling to one side of the display and selecting the desired map from the Touch Screen options. If a change is made to the default display, it will be remembered by the system. A customized preset can also be created with the desired settings. Notes No. 58 B-mode reference image SIEMENS. Healthineers ... Rotate VT to change 2D SWE transparency in ROI 10L4 10L4 Breast Breast TIB:0.36 TIB:0.36 TIC.0.77 TIC:0.77 TIS:0.36 TIS:0.36 ML:1.31 MI:1.31 46fps VT 46fps 95% 95% 2D 2D H Mid H Mid 0dB/DR65 OdB/DR65 SWE SWE Velocitv Velocity Transp: 100%% Transp: 20% 3.5 cm 3.5cm Transparency: 100 % Transparency: 20 % 59 Unrestricted © Siemens Healthineers 2024 Speaker Notes: To better correlate anatomic locations between the B-mode image and the 2D SWE image, you can rotate the VT control located on the Control Panel to change the transparency of the 2D SWE image. In this image, the transparency has been changed from 100% to 20% to better assess the B-mode image correlation with the 2D SWE image. Notes No. 59 2D SWE measurement controls SIEMENS . Healthineers ... Default Virtual Touch Exam Package Breast Mamma TIB:0,46 TIC:0,93 Patient Right Left Shadow MI:1.16 Imaging 95% 2D Hoch Review 08 0865 Mass 1 Mass 2 Mass 3 Site 1 Site 2 Site 3 geschw2 LD 1 Report JA 2 End Exam O Transparenz. 80% Gs Median=1,54 m/s O E Median=7,1 kPa Distance Ellipse Open Trace Tiefe=1,99 cm Stenosis A %Stenosis Diam=0,30 cm Clear Screen Last Caliper Ol Diamet 3 mm Hide Results Image courtesy of Martin Danialex, D. University of Innsbruck, Austria 60 Unrestricted © Siemens Healthineers 2024 Speaker Notes: Shear wave measurements can be performed in the Velocity or Elasticity, Quality or Displacement maps. Multiple shear wave measurements can be made anywhere within the 2D SWE ROI on a single acquisition. 2D SWE supports both measure-then-label and label-then- measure methods and includes a set of measurement labels: Up to ten sites or masses. Note: MSK measurement labels are not available; however, thyroid measurement labels are available if needed. To measure, you would first press Caliper on the Control Panel. The system activates the Shear Velocity measurement tool. Roll the trackball to position the measurement ROI inside the 2D SWE ROI and rotate ROI Diameter to adjust its size anywhere from 3-20 mm in diameter as needed. When Shadow is activated in Live Dual, the measurement is duplicated and displayed on the adjacent image for a comparison of lesion size and/or location. The shear wave measurements, depth and diameter are displayed near the image. To enter a measurement into the report, you would select a measurement label and press the right or left Set key. To perform additional measurements, roll the trackball, select a measurement label and press the right or left Set key. Select Delete on the Control Panel to delete the measurement(s) on the monitor (this will not delete measurements stored to the Report). Select Report on the left side of the Touch Screen to view, delete, store, print, or transfer shear wave measurements. Notes No. 60 2D SWE measurements SIEMENS . Healthineers ... Values exceeding maximum Values are lower than Values are not detected in ROI measurement setting minimum setting or measured outside ROI 1 Vs Median=High 1 Vs Median=Low 1 Vs Median=X.XX E Median=High E Median=Low E Median=XX.X Depth=2.00 cm Depth=2.00 cm Depth=2.00 cm Diam=0.30 cm Diam=0.30 cm Diam=0.30 cm 61 Unrestricted © Siemens Healthineers 2024 Speaker Notes: If the measurement ROI value exceeds the current maximum velocity or elasticity setting, the measured results display HIGH for the shear wave value. If the measurement ROI value is lower than the current minimum velocity or elasticity setting, the measured results display LOW. The measured results will display an “X” value if the shear wave was not detected within the measurement ROI or if a measurement is performed outside of the 2D SWE ROI. Notes No. 61 Best practice techniques 2D SWE SIEMENS . Healthineers' ... 10L4 • Position patient to obtain perpendicular plane to MSK TIB:0.34 skin TIC:0.67 TIS:0.34 MI:1.37 33fps Use ample gel to maintain adequate contact 95% • 2D H High B /CR65 • Use minimal scanning pressure to avoid 580 elevated shear wave values and unreliable measurements SWE -1 Vs Median=11.51 m/s E Median=397.5 kPa Depth=0.73 cm Diam=0.30 cm Vs Median=11.25 m/s E Median=379.8 kPa Depth=0.73 cm Diam=0.30 cm 5 Vs Median=11.07 m/s E Median=367.5 kPa Depth=0.72 cm Diam=0.30 cm 62 Unrestricted © Siemens Healthineers 2024 Speaker Notes: Use best practice techniques when performing 2D SWE for reliable and repeatable results. Optimize the scan direction by positioning the patient to obtain as much of a perpendicular plane to skin surface as possible. Use ample gel so that the transducer surface is in continuous contact with the skin surface. Apply the appropriate amount of scanning pressure, using minimal compression for optimal results. Excessive pressure with the transducer may artificially elevate shear wave values and result in unreliable shear wave measurements. The 10L4 transducer has been specifically optimized for musculoskeletal elastography. It works best for linear structures that are parallel to the transducer face as displayed here in the Achilles tendon. Notes No. 62 Shear waves in cysts SIEMENS . Healthineers ... Velocity Quality Displacement 20 H Md 20 5dB/DRES 58B/DR85 H MIC 50B/DASS c# 1446 c-1446 C# 1446 SWE SWE Velocity Cualty SWE Transp: 60% Deplacement Transp: 60% Transp: 80% 63 Unrestricted © Siemens Healthineers 2024 Speaker Notes: It is important to understand what happens when the ultrasound beam encounters a “pure” cyst when performing shear wave elastography. Shear waves cannot travel in clear, non-viscous liquid. In this fluid-filled “pure” cyst, shear waves are not induced; therefore, the shear wave velocity or elasticity is undetectable, and a blank signal with no color is displayed. The “Quality” map shows us that the shear waves within the cyst are of low quality, they are not detectable or non-determinant. The Displacement map reveals the characteristic “bull’s-eye” appearance of a cyst. The “bull’s-eye” appears as a dark ring surrounding a bright, echogenic center, with a posterior white spot. The “bull’s-eye” occurs from decorrelation between images caused by fluid movement in the cyst. Notes No. 63 Shear waves in very stiff lesion SIEMENS . Healthineers ... Velocity Quality Displacement 3.Son 64 Unrestricted © Siemens Healthineers 2024 Speaker Notes: The Displacement map should be used in conjunction with the other maps to help identify potential artifacts, especially in very stiff lesions. For example, the “Blue Cancer” appearance, is the result of a very stiff breast lesion that attenuates the Acoustic Radiation Force Imaging (ARFI) beam resulting in a lower SWE velocity and a soft appearance or “Blue cancer”.* The Quality map shows, in red and yellow, that the lesion has low quality shear wave signals that are not reliable estimates of true stiffness. The Displacement map in this example would indicate an artificially low velocity in a very hard lesion. *Barr, Richard G and Zheng Zhang. “Shear-wave elastography of the breast: value of a quality measure and comparison with strain elastography.” Radiology 275 1 (2015): 45-53. DOI:10.1148/radiol.14132404. Notes No. 64 2D SWE breast lesion assessment SIEMENS . Healthineers ... • Area of stiff tissue, breast clip and high resolution of small calcification • Stiffness heterogeneity well visualized in 2D SWE • Quality is good for confidence in measurement placement and accuracy TOLA isipe 20 Strain Color D Map O 65 Unrestricted © Siemens Healthineers 2024 Speaker Notes: Breast lesions can span an unusually wide range of elastic values. Strain imaging provides information about the relative stiffness differences of all the tissue represented in the region of interest (ROI); whereas, in 2D SWE, the image is composed of many thousands of discrete shear wave measurement samples, thus stiffness heterogeneity is well visualized. These discrete shear wave measurement samples also contribute to 2D SWE’s high spatial resolution for greater confidence in measurement placement and accuracy. In this example, the strain image on the left displays an area of stiffness. The known breast clip and area of calcification displayed on the B-mode image are difficult to visualize on the elastogram. The 2D SWE image in the middle shows an area of moderately high shear wave velocities (in green), a small area of high velocities (in red) where the breast clip is located and a second, even smaller area, of high shear wave velocity (in red) where a small calcification is located . The Quality display on the right is mostly green with a small area of red; therefore, if the measurement ROI is placed in the green area of the Quality display (i.e., not in the clip and calcification), we can feel confident about its accuracy in measuring tissue. The quality display adds information that is helpful in interpreting shear wave images. Notes No. 65 2D SWE thyroid lesion assessment SIEMENS . Healthineers ... • Stiffness heterogeneity • Quality is good for confidence in measurement placement and accuracy • FNA (fine needle aspiration) guidance to the “hot spots” 18LG Thyroid TIB:0.57 TIC:0.73 TIS.0.57 51.11 42fps YOcity DEcliccon Vs Median=2.87 m/s Vs Median=2.87 m/s E Median-24.8 kPa E Median-24.8 kPa Vs Median=2.87 m/s E Median-24.8 kPa Depth=1.58 cm Depth=1.58 cm Depth=1.58 cm Diam=0,30 cm 2 Vs Median=2.30 m/s Diam=0,30 cm 2 Vs Median=2.30 m/s Diam=0,30 cm 2 Vs Median=2.30 m/s E Median=15.9 kPa E Median=15.9 kPa E Median=15.9 kPa Depth=1,79 cm Diam=0.30 cm Depth=1,79 cm Depth=1,79 cm Diam=0.30 cm 3 Vs Median=2.23 m/s 3 Vs Median=2.23 m/s Diam=0.30 cm E Median=14.9 kPa E Median=14.9 kPa 3 Vs Median=2.23 m/s E Median=14.9 kPa Depth=1.18 cm Depth=1.18 cm Diam=0.30 cm Diam=0.30 cm Depth=1.18 cm Diam=0.30 cm 66 Unrestricted © Siemens Healthineers 2024 Speaker Notes: Thyroid lesions can be heterogeneous. Research has shown that elastography is an additional tool for thyroid lesion differentiation and may guide the user to the “hot spots” for measurement and guides the FNA (fine needle aspiration) to the stiffest areas.* *Cosgrove, D, et al. (2013). “EFSUMB Guidelines and Recommendations on the Clinical Use of Ultrasound Elastography. Part 2: Clinical Applications.” Ultraschall in Der Medizin - European Journal of Ultrasound, 34(03): 238-253. doi:10.1055/s-0033-1335375. Notes No. 66 2D SWE musculoskeletal assessment SIEMENS . Healthineers ... • Very stiff, echogenic, linear structures • Degenerative disease monitoring • Injury/repair evaluation 10L4 10L4 MSK TIB:0.34 TIC:0.67 TIS:0.34 MI:1.37 33fps 95% 2D 2D O.O.C H High dB/CR65 C=1580 SWE MapC/TE Blocity SWE Velocity Transp: 70% .1 Vs Median=11.51 m/s E Median=397.5 kPa Depth=0.73 cm Diam=0.30 cm 67 Unrestricted © Siemens Healthineers 2024 Speaker Notes: Conventional 2D ultrasound is widely used to assess the musculoskeletal system because ultrasound enables clinicians to assess structures dynamically in real-time. Shear wave elastography adds another dimension to the ultrasound exam by allowing clinicians to diagnosis tissue characteristics of tendons, ligaments, and muscles. 2D SWE is can be used to image these very stiff and linear structures for degenerative disease monitoring or progress of healing post injury or repair. Ryu, J., & Jeong, W. K. (2017). Current status of musculoskeletal application of shear wave elastography. Ultrasonography (Seoul, Korea), 36(3), 185–197. https://doi.org/10.14366/usg.16053 Notes No. 67 2D SWE liver assessment SIEMENS . Healthineers ... 5C1 DAX Abdomen Workflow 501 Segugio 1 Vs Median=0.85 m/s Abdomen E Median=2.2 kPa TIB:0.71 Patient 2D Virtual Touch Depth=4 33 cm TIC:1.49 Diam=1.00 cm TIS:0.71 MI:1.39 26fps Imaging 98% PSWE / UDFF SWE 20 Review 0GB DR60 SWE Report Socity O End Exam Quality Velocity m/s Live Dual Transparency 60% Compounding × Frequency Min Velocity Max Velocity Min Elasticity Max Elasticity H Low 0.5 50 68 Unrestricted © Siemens Healthineers 2024 Speaker Notes: The ACUSON Sequoia system offers flexibility for user preference in Virtual Touch liver applications. It provides an image of stiffness that can be used to assess stiffness heterogeneity in the liver. It can be used during placement of the measurement ROI in a homogeneous region of the liver to help avoid potential sources of artifact (e.g., areas not visualized on the B-mode image) for less measurement variability and greater measurement reliability. Note that there is no B-mode degradation upon entering 2D SWE. The controls are similar to the controls previously covered for small parts applications. The recommended technique is similar to the technique recommended when using pSWE; however, five measurements can be made (versus 10 measurements recommended for pSWE). The 2D SWE ROI can be positioned closer to the liver capsule, if reverberation artifacts are avoided; however, the measurement ROI should be positioned at least 1.5 – 2 cm below the liver capsule. Perform one measurement per acquisition. Studies have shown that the level of variability between consecutive acquisitions, assessed by means of IQR/Median ratio, is the most important quality criterion.* *Barr, RG, et al. (2021),“Update to the Society of Radiologists in Ultrasound Liver Elastography Consensus Statement.” Radiology, 00:1-12. doi.org/10.1148/radiol.2021192437. https://pubs.rsna.org/doi/10.1148/radiol.2021192437 Notes No. 68 2D SWE liver assessment report SIEMENS. Healthineers .. Liver Shear Wave Elastography Measurements (SWE) • Valid result: Interquartile Range (IQR)/Median ratio of ≤ 0.3 for values in Liver Site 1 Median Mean Max Median Mean Max Depth Diam (m/s) (kra) (kPa) (kPa) (cm) (cm) kPa and ≤ 0.15 for values in m/s 1.04 1.08 1.40 3.5 5.9 5.05 1.00 1.06 1.38 3.1 E'E 3.4 5.8 15.04 1.00 The recommended quality control 0.99 1.05 1.39 2.9 3.3 5.8 5.01 1.00 • 1.09 1.10 1.40 3.7 5.9 5.10 1.00 1.10 1.11 1.40 3.6 9'E 3.7 5.9 5.12 1.00 measure for adequate technical quality* Mean 1.05 1.08 1.39 3.3 3.5 5.9 Std Dev 0.05 0.03 0.01 0.3 0.2 0.1 Median 1.04 1.08 1.40 3.5 5.9 • Shear wave values may vary note on IQR 0.10 0.05 0.02 0.6 E'E 0.4 0.1 IQR/Median 0.10 0.00 0.00 0.2 0.1 0.0 report page Overall Statistics Mean 1.05 m/s Std Dev 0.05 m/s Median 1.04 m/s IQR 0.10 m/s QR/Median 0.10 Mean 3.3 kPa Std Dev 0.3 kPa Median 3.3 kPa QR 0.6 kPa QR/Median 0.2 Note: Shear Wave Speed and Elasticity values may vary among manufacturers! *Barr, RG, et al. (2021),“Update to the Society of Radiologists in Ultrasound Liver Elastography Consensus Statement.” Radiology, 00:1-12. doi.org/10.1148/radiol.2021192437. https://pubs.rsna.org/doi/10.1148/radiol.2021192437 69 Unrestricted © Siemens Healthineers 2024 Speaker Notes: Displayed here is the liver assessment report containing each of the measurements along with the statistical data in units of m/s and kPa. It includes the Interquartile Range (IQR), which is the range of the spread of values in a repeated data set, from the 25th to 75th percentile. It is sometimes referred to as the “middle fifty”. It removes outlying measurements to more accurately represent the spread of values in a data set. The median shear wave value is used with the IQR to calculate the Interquartile Range to Median (IQR/Median) ratio. An IQR/Median ratio of ≤ 0.3 for values in kPa and ≤ 0.15 for values in m/s indicates that the variability of measurements lies within a reasonable variability range. It is the recommended quality control measure for adequate technical quality. A higher ratio indicates significant variability in the shear wave measurements, decreasing the reliability of measurement results. The IQR will be higher with advancing fibrosis; since the IQR/Median ratio normalizes for this increase, it is an important indicator of technical accuracy. Note: The IQR/Median ratio for elasticity in units of kPa will 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. Absolute values for shear wave measurements may vary among different manufacturers due to multiple system-dependent factors, including shear wave frequency, excitation beam (push beam) frequency, shear wave detection techniques, and shear wave measurement estimation methods. Notes No. 69 Objectives SIEMENS . Healthineers ... • Explain the basis of Virtual Touch technologies and tissue biomechanics • Demonstrate imaging controls and techniques for: • Strain imaging • Point shear wave (pSWE) • Auto point shear wave (Auto pSWE) • 2D shear wave (2D SWE) • Outline technology comparisons, clinical considerations and supporting clinical evidence for elastography exams 70 Unrestricted © Siemens Healthineers 2024 Speaker Notes: No speaker notes. Image: HOOD05162003330011 Notes No. 70 Strain imaging SIEMENS. Healthineers ... High sensitivity, but difficulty defining the lesion size (boundaries) in isoelastic benign lesions reduces specificity Site Total Lesion Malignant EI/B-mode Sensitivity Benign EI/B-mode Specificity Lesions Ratio≥1 Lesions Ratio<1 1 251 54 54 100% 197 188 95.4% 2 79 40 40 100% 39 26 66.7% 3 206 90 87 96.7% 116 100 86.2% 4 52 14 14 100% 38 29 76.3% 5 34 18 18 100% 16 12 75.0% 6 13 6 6 100% 7 6 85.7% Total 635 222 219 98.6% 413 361 87.4% Evaluation of Breast Lesions Using Ultrasound Elasticity Imaging: A Multi-centered Trial Barr RG, Destounis S, Lackey LB, Svensson WE, Balleyguier C, Smith C., Journal of Ultrasound in Medicine, 2012 Feb; 31(2): 281-7 71 Unrestricted © Siemens Healthineers 2024 Speaker Notes: Strain imaging has been widely used in breast and thyroid imaging and is still relevant today as a highly sensitive indicator of relative tissue stiffness in focal lesions. In this multi-centerstudy at six locations around the world, the reproducibility of strain imaging used in breast lesions yielded 97 – 100% sensitivity in all locations. Specificity was lower, primarily due to the difficulty in defining the lesion size (boundaries) in benign lesions, which are relatively isoelastic when compared to normal breast tissue. Notes No. 71 Patient factors SIEMENS . Healthineers ... Liver assessment Patient factors can result in an overestimation of liver Laboratory findings Acute hepatocellular Cholestatic joundice Chronic alcoholic stiffness damage cirrhosis Serum total bilirubin • Liver function – elevated alanine aminotransferase Serum conjugated bilirubin (ALT) or aspartate aminotransferase (AST) Serum unconjugated bilirubin N • Underlying disorders or diseases such as ALT 111 N/ obstructive cholestasis, liver congestion, acute AST 11 N/1 hepatitis and infiltrative liver disease ALP 111 GGT 111 -- Serum albumin N N 72 Unrestricted © Siemens Healthineers 2024 Speaker Notes: Patient factors can also result in abnormal shear wave measurement values. These factors should be checked before performing liver stiffness measurements in order to avoid overestimation and should be considered when interpreting the results.* Alanine aminotransferase (ALT) levels or aspartate aminotransferase (AST) are blood tests that check for liver damage. When they are significantly elevated above the normal limit, they can indicate liver inflammation as shown here in the table on the right. Underlying disorders or diseases such as obstructive cholestasis, liver congestion, acute hepatitis and infiltrative liver disease can also result in overestimation of liver stiffness. Be aware of the patient’s medical history prior to performing a shear wave examination. *Dietrich, CF, et al. (2017), “EFSUMB Guidelines and Recommendations on the Clinical Use of Liver Ultrasound Elastography, update 2017 (long and short version).” Ultraschall in Der Medizin European Journal of Ultrasound, 38(03), 327-329. doi:10.1055/s-0043-111135. - https://www.thieme-connect.de/products/ejournals/pdf/10.1055/s-0043-103955.pdf Notes No. 72 Complimentary applications SIEMENS . Healthineers ... Property Strain imaging 2D SWE Quantitative + ++++ Cyst characterization ++++ ++ Sensitivity (Is it Positive?) ++++ ++ Specificity (Is it Negative?) ++ ++++ 73 Unrestricted © Siemens Healthineers 2024 Speaker Notes: Siemens Healthineers offers complimentary Virtual Touch applications for breast and thyroid. Advantages of one application can be the challenge of the other. The combination increases the sensitivity and specificity of the exam, increasing confidence in the diagnosis. Property relative ranking for each application: + (least) to ++++ (greatest) advantage. Notes No. 73 Flexibility in applications SIEMENS. Healthineers ... Liver Property pSWE Auto pSWE 2D SWE Quantitative ++++ ++++ ++++ Measurement depth ++++ +++ +++ Cooling time ++++ +++ ++ Heterogeneity assessment ++ +++ ++++ Artifact identification ++ ++ ++++ # of measurements per + ++++ +++ acquisition (workflow) 74 Unrestricted © Siemens Healthineers 2024 Speaker Notes: Siemens Healthineers offers flexibility for user preference in Virtual Touch applications for the liver. Property relative ranking for each application from + (least) to ++++ (greatest) advantage. Notes No. 74 Viscoelasticity impact on estimated shear wave speed SIEMENS . Healthineers ... Difference between vendors • Different signal processing optimizations use different frequency bands 4.5 • Shear wave speeds can be estimated by using either the lower High Viscosity Low Viscosity or higher frequency bands Linear, Elastic 4 Siemens Vendor A Example • Vendors differ in which portion of the frequency spectrum that Vendor B Example they emphasize 3.5 CS = [2.24, 2.33, 2.65] m/s CA = [2.24, 2.37, 2.92] m/s Estimates of the SWS using either portion of the spectrum are CE = [2.24, 2.40, 3.46] m/s • 3 valid, accurate and demonstrate the same trends in tissues of Estimated SWS (m/s) increasing stiffness 2.5 2 Shear Wave Center Frequency (Hz) Note: frequency bands for display only, not the actual frequency bands used in SWS estimation 75 Unrestricted © Siemens Healthineers 2024 Speaker Notes: Shear wave values do differ from vendor to vendor. This is due to what portion of the shear wave spectrum is used in the speed calculation. As we discussed earlier in this presentation, viscoelastic tissues like the liver, have a frequency dependent shear wave speed which increases with increasing frequency of the shear wave. The signal processing algorithms used in optimization to estimate the shear wave speed influence the frequency content and therefore the final estimated shear wave speed. Differential signal processing optimizations (such as found between vendors) result in using different frequency bands for estimating shear wave speed. An example of this impact is shown in the plot on the right, which displays three examples emphasizing three different frequency bands resulting in three different estimates of the same shear wave speed. Siemens Healthineers ultrasound products tend to emphasize lower frequency bands while other vendors emphasize higher frequency bands. Vendors that emphasize higher frequency bands will have results that are higher in estimated shear wave speed in viscoelastic tissues than those that emphasize the lower portion of the spectrum. All estimates of shear wave speed are valid, accurate and demonstrate the same trends in tissues of increasing stiffness regardless of which section of the spectrum is used to generate the result. Notes No. 75 Shear wave cut-off values ACUSON Sequoia ultrasound system* SIEMENS. Healthineers ... Virtual Touch Reference Values Absent or mild fibrosis Significant fibrosis Severe fibrosis Cirrhosis IQR/Median Ratio Recommendations PSWE/2DSWE: <15% (m/s), <30% (kPa) Auto pSWE: <30% (m/s), <60% (kPa) Metavir Score FO-F1 F2 F3 F4 Siemens Healthineers 1.2 m/s 1.3 ml 1.5 m/s 1.7 m/s valuest 4 kPa 5 kPa 7 kPa 9 kPa 1.3 m/s 1.7 mls 2.1 mls Society of Radiologists <5 kPa Likely Normal Not applicable < 9 kPa rules out cACLD in the in Ultrasound (SRU)++ absence of other clinical signs 9-13 kPa suggestive of cACLD > 13 kPa rules in CACLD needs further testing 10 sample median; IQRIMedian < 15% m/s, < 30% kPa. CACLD - compensated Advanced Chronic Liver Disease. This guide is based on meta-analysis and clinical studies using Siemens Healthineers Ultrasound. This guide is not intended to be used as a conversion table for liv ge or replace the performing physician's judgment for the final diagnosis. a conversion table for liver stiffness readings to fibrosis stage or replace the performing physician's judgment for the fi *Data on file. 76 Unrestricted © Siemens Healthineers 2024 Speaker Notes: As mentioned in the previous slide, different vendors use different proprietary methods to measure the shear wave speed. These variations should be noted when interpreting the threshold values used to assign patients into a fibrosis (F0, F1, F2, and F4) category and a manufacturer-specific chart should be consulted. A detailed chart of the values for the ACUSON Sequoia ultrasound system can be found on this slide. Image: HOOD05162003264616 Notes No. 76 Siemens Healthineers Virtual Touch technologies SIEMENS. Healthineers ... Clinical evidence • Siemens Healthineers first to have ARFI-based technologies Radiology • Worldwide adoption since 2008 • Several hundred papers Thyroid • Multiple specialties • Nearly 1,000 sites worldwide IRSN JOURNAL OF HEPATOLOGY 77 Unrestricted © Siemens Healthineers 2024 Speaker Notes: When you expand your clinical offering with a critical new technology such as elastography, it is important to choose a partner that has industry leading advanced elastography solutions with strong clinical validation so that you can be confident of its adoption into personalized clinical pathways. Siemens Healthineers provides this partnership with confidence leading the way with over 400 publications since the introduction of elastography in 2008. We encourage you to investigate and discover for yourself the clinical validity of our technology at the third-party research database at www.mendeley.com. Notes No. 77 Trademarks and disclaimers SIEMENS . Healthineers ... ACUSON Sequoia and Virtual Touch are registered trademarks of Siemens Medical Solutions USA, Inc. 78 Unrestricted © Siemens Healthineers 2024 Speaker Notes: No speaker notes. Notes No. 78 Thank you for your enthusiasm! SIEMENS. Healthineers ... Questions? 79 Unrestricted © Siemens Healthineers 2024 Speaker Notes: No speaker notes. Notes No. 79