Static and dynamic light and ultrasound measurements for the elucidation of biological and biomaterial structure and function

静态和动态光和超声波测量，用于阐明生物和生物材料的结构和功能

• 批准号: 216986-2012
• 负责人: Kolios, Michael
• 金额: $ 3.72万
• 依托单位: Ryerson University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2013
• 资助国家: 加拿大
• 起止时间: 2013-01-01 至 2014-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=523650
• 关键词: Static; dynamic; light; ultrasound; measurements

The objective of the proposal is to develop optical and ultrasound techniques to characterise the functional state of cells and tissues using optical, ultrasound and photoacoustic techniques. My work to date has been focused on using static optical and ultrasound scattering. In the proposed work these static techniques will be refined based on new knowledge generated from recent theoretical and experimental findings. The main novelty of the new work proposed will be a) to extend the techniques developed to include photoacoustic tissue characterization and b) to extended the static ultrasound and optical scattering measurements to include dynamic scattering measurements (fluctuations of scattering intensity as a function of time) to infer the states of cells and tissues. Whereas the field of photoacoustic imaging has recently gained a lot of attention, fundamental questions as to the origin of the photoacoustic signal and how to characterize the signal when blood vessels (the main generator of photoacoustic signals) are unresolved remain unanswered. As for most clinically relevant ultrasound frequencies blood vessels of interest cannot be resolved, a new technique is required to analyze the photoacoustic signals. New techniques based on modeling the photoacoustic signals generated by individual blood vessels will be used to develop methods for photoacoustic tissue characterization. In parallel, techniques will be also developed based on the fluctuations of (optical / ultrasound) scattering intensity as a function of time. We recently discovered that dying cells exhibit significantly shorter optical coherence tomography speckle decorrelation times (faster fluctuations of scattering intensity as a function of time), and that the speckle decorrelation time can be used to assess intracellular motion of the main scattering sources within cells / tissues. While the most common application relates to blood flow measurements, in these new techniques signals from blood are supressed so as to assess motion in tissues and cells alone. The optical and ultrasound techniques developed will aid in the non-invasive monitoring of the functional states of cells and tissues.

该提案的目标是开发光学和超声技术，以利用光学、超声和光声技术来检测细胞和组织的功能状态。迄今为止，我的工作一直集中在使用静态光学和超声散射。在拟议的工作中，这些静态技术将根据最近的理论和实验结果产生的新知识进行改进。所提出的新工作的主要新奇将是a）将所开发的技术扩展到包括光声组织表征和B）将静态超声和光学散射测量扩展到包括动态散射测量（散射强度作为时间的函数的波动）以推断细胞和组织的状态。鉴于光声成像领域最近获得了很多关注，光声信号的起源以及如何在血管（光声信号的主要产生器）未解决时表征信号的基本问题仍然没有得到回答。由于大多数临床相关的超声频率的感兴趣的血管不能解决，需要一种新的技术来分析光声信号。基于模拟单个血管产生的光声信号的新技术将用于开发光声组织表征的方法。与此同时，还将开发基于（光学/超声）散射强度随时间变化的波动的技术。我们最近发现，垂死的细胞表现出显着更短的光学相干断层扫描散斑去相关时间（散射强度作为时间的函数的更快的波动），并且散斑去相关时间可以用来评估细胞/组织内的主要散射源的细胞内运动。虽然最常见的应用涉及血流测量，但在这些新技术中，来自血液的信号被抑制，以便单独评估组织和细胞中的运动。开发的光学和超声技术将有助于对细胞和组织的功能状态进行非侵入性监测。