Description:
Background:
Ultrasound elastography, specifically shear wave elastography (SWE), is essential for non-invasive assessment of tissue stiffness, an important biomarker for diagnosing and monitoring diseases such as liver fibrosis, cancer, and ocular conditions. While conventional two-dimensional SWE provides valuable clinical insights, accurately characterizing tissue mechanical properties requires comprehensive three-dimensional (3D) and four-dimensional (4D) imaging (3D spatial plus temporal). Current volumetric SWE technologies face significant constraints, primarily due to hardware limitations inherent to standard ultrasound systems, which are incompatible with the large 2D matrix arrays required for true high-resolution 3D imaging. Existing methods using mechanical scanning or smaller arrays compromise spatial coverage, resolution, and imaging speed, resulting in fragmented shear wave reconstructions and reduced diagnostic accuracy.
Technology Overview:
Sequential-based Excitation Shear Wave Elastography (SE-SWE) addresses these challenges through advanced ultrasound imaging, achieving high-resolution 4D elastography using a 1024-element two-dimensional matrix array operated with a standard 256-channel ultrasound system. The approach partitions the array into four sub-sections, sequentially stimulated by an external mechanical shaker. During each excitation, high-frame-rate radiofrequency data is captured from one array subsection using multi-angle plane wave transmissions. This collected data undergoes offline beamforming and compounding, producing a comprehensive volumetric shear wave propagation image. Shear wave velocity, derived from phase changes in the wave propagation, allows generation of high-resolution volumetric tissue stiffness maps with approximately 1.6 mm spatial resolution. SE-SWE thus significantly improves volumetric imaging by circumventing multiplexing complexities, enabling detailed dynamic tissue stiffness characterization without necessitating specialized high-channel-count ultrasound hardware.
Benefits:
Enables comprehensive four-dimensional (volumetric plus temporal) shear wave elastography. Overcomes hardware limitations of standard ultrasound systems, facilitating the use of large matrix arrays. Delivers detailed tissue stiffness mapping with high spatial resolution (~1.6 mm). Provides rapid volumetric imaging for accurate assessment of dynamic tissue properties.
Applications: