Ultrasound hepatic elastography: A non-invasive indicator of insulin resistance in the pediatric population: A systematic review

Figure 7 The principle of shear wave elastography for fibrosis assessment. This schematic illustrates how shear wave elastography and acoustic radiation force impulse measure liver stiffness [shear wave velocity (SWV), measured in m/second or converted to kPa]. Unlike transient elastography, the shear wave is generated by a focused, acoustic push pulse emitted from a conventional ultrasound probe. This pulse perturbs the tissue, creating a shear wave that travels laterally. In normal liver tissue (low fibrosis), the wave travels slower, yielding a low SWV value. In fibrotic liver tissue (high stiffness), the wave travels faster. The system measures this speed and presents the result as a quantitative value (SWV) and often as a 2D color map, enabling real-time visualization of the stiffness distribution. This technique provides a non-invasive assessment of the inflammatory and fibrotic components of metabolic dysfunction-associated steatotic liver disease. ARFI: Acoustic radiation force impulse; SWE: Shear wave elastography; SWV: Shear wave velocity.