生物组织弹性成像方法及其新技术进展

Advances in New Technologies for Tissue Elastography

弹性是一种描述物质物理意义的重要参数,在描述物质在热力学和动力学的变化过程中有着重要的意义。在医学上,弹性的变化往往和病变联系在一起。然而,绝大多数生物组织在他们的力学特性上所表现出的复杂性并不是弹性模量一项参数就可以完全表述的,在对于他们的粘弹性表征和流变学行为的描述中,粘滞性往往和弹性一样的重要。现在被广泛用来对生物组织机械特性表征的成像技术是弹性成像,其基本原理是给组织施加一个激励,组织会产生一个响应,而该响应的分布结合技术的处理方法,可以反映出其弹性模量等力学属性的差异。本文介绍了生物组织常见的弹性成像方法:超声弹性成像,磁共振弹性成像以及光学相干弹性成像;详细阐述了新发展起来的技术-光声弹性成像和光声粘弹成像,并讨论分析其应用前景。

Elastic property is an important parameter closely connected to the thermodynamic properties of materials and can be related to a wide range of physical parameters. Changes in elasticity of tissues are often related to pathology.However,elasticity is insufficient to fully describe the complexity of mechanical properties of most biological tissues,and in the description of viscoelastic rheological characterization,viscosity is also important. The present method used widely to characterize the mechanical properties of tissue is elasticity imaging,its basic principle is that the biological tissue is excited,and the tissue will produce a response. The distribution of response is combined with the processing method of technology,which directly or indirectly reflects the differences in the elastic modulus and other mechanical properties.This paper introduces the common imaging methods for the elasticity of biological tissue： ultrasounic elastography,magnetic resonance elastography and optical coherence elastography; it elaborates two new development technologies： photoacoustic elastography and photoacoustic viscoelasticity imaging,and discusses their application prospect.