Crutison Joseph, Sun Michael, Royston Thomas J
Richard and Loan Hill Department of Biomedical Engineering, University of Illinois Chicago, 851 South Morgan Street, MC 063, Chicago, Illinois 60607, USA.
J Acoust Soc Am. 2022 Apr;151(4):2403. doi: 10.1121/10.0010110.
Dynamic elastography, whether based on magnetic resonance, ultrasound, or optical modalities, attempts to reconstruct quantitative maps of the viscoelastic properties of biological tissue, properties that are altered by disease and injury, by noninvasively measuring mechanical wave motion in the tissue. Most reconstruction strategies that have been developed neglect boundary conditions, including quasistatic tensile or compressive loading resulting in a nonzero prestress. Significant prestress is inherent to the functional role of some biological tissues currently being studied using elastography, such as skeletal and cardiac muscle, arterial walls, and the cornea. In the present article, we review how prestress alters both bulk mechanical wave motion and wave motion in one- and two-dimensional waveguides. Key findings are linked to studies on skeletal muscle and the human cornea, as one- and two-dimensional waveguide examples. This study highlights the underappreciated combined acoustoelastic and waveguide challenge to elastography. Can elastography truly determine viscoelastic properties of a material when what it is measuring is affected by both these material properties and unknown prestress and other boundary conditions?
动态弹性成像，无论是基于磁共振、超声还是光学模态，都试图通过非侵入性地测量组织中的机械波运动，来重建生物组织粘弹性特性的定量图谱，这些特性会因疾病和损伤而改变。大多数已开发的重建策略都忽略了边界条件，包括导致非零预应力的准静态拉伸或压缩载荷。显著的预应力是目前使用弹性成像研究的一些生物组织功能作用所固有的，如骨骼肌、心肌、动脉壁和角膜。在本文中，我们回顾了预应力如何改变一维和二维波导中的体机械波运动和波动。关键发现与作为一维和二维波导示例的骨骼肌和人角膜的研究相关。这项研究突出了弹性成像中未得到充分重视的声弹性和波导综合挑战。当弹性成像所测量的受这些材料特性以及未知预应力和其他边界条件影响时，它真的能确定材料的粘弹性特性吗？
