Bubble Based Acoustic Force Elasticity for Presbyopia

基于气泡的声力弹性治疗老花眼

• 批准号: 6921094
• 负责人: KYLE W HOLLMAN
• 金额: $ 22.16万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-04-01 至 2007-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6921094
• 关键词: animal tissue; bioengineering /biomedical engineering; bioimaging /biomedical imaging; biophysics; elasticity; eye refraction disorder; human tissue; lasers; lens; mathematical model; model design /development; phantom model; postmortem; radiation; technology /technique development; ultrasound biological effect; viscosity

DESCRIPTION (provided by applicant): The main goal of this project is to develop new technology to measure tissue elasticity by deforming it with acoustic radiation force applied to femtosecond laser produced microbubbles. First we will study physical functional relationships by measuring bubble motion in gelatin phantoms with known elastic and viscoelastic properties. Bubbles will be placed in these specimens with photodisruption from a femtosecond pulsed laser so that bubble size and position can be controlled. The bubble is displaced by acoustic radiation force from a high amplitude tone burst originating from one ultrasonic transducer and tracked by a broadband, low amplitude signal from a secondary high-frequency (50-100 MHz) transducer. Relationships between physical parameters can be used to determine elastic and viscoelastic properties in unknown specimens. After initial development, the technique will be validated on animal and then human lenses, and then used to map the spatial variation in these tissues. Preliminary experiments for this proposal would be limited to cadaverous tissues. These results will be helpful for future research with this technique on manipulating lens elasticity by photodisrupting small areas of tissue in a loosely spaced grid. In another application, with further development of equipment, this technique could be modified to measure elasticity of structures within individual cells. It is the aim, therefore, of this proposed work to address the following issues in detail: 1) Experimentally determine the relationship between physical parameters in three main areas: elastic media, acoustics, and bubbles. 2) Develop theory and mathematical models to yield insight on experimental results and to calculate unknown viscoelastic properties of specimens from measured properties. 3) Test and refine this method by mapping the spatial distribution of elasticity in tissue with medical significance, the intraocular lens.

描述（由申请人提供）：该项目的主要目标是开发新技术，通过对飞秒激光产生的微泡施加声辐射力使组织变形来测量组织弹性。首先，我们将通过测量具有已知弹性和粘弹性特性的明胶模型中的气泡运动来研究物理功能关系。通过飞秒脉冲激光的光致破裂，将气泡放置在这些样本中，以便控制气泡的大小和位置。气泡被来自一个超声换能器的高振幅音调爆发的声辐射力所取代，并被来自第二高频 (50-100 MHz) 换能器的宽带、低振幅信号跟踪。物理参数之间的关系可用于确定未知样本的弹性和粘弹性特性。 经过初步开发后，该技术将在动物和人类镜头上进行验证，然后用于绘制这些组织的空间变化。该提议的初步实验仅限于尸体组织。这些结果将有助于未来研究通过光破坏松散网格中的小区域组织来操纵晶状体弹性的技术。在另一个应用中，随着设备的进一步发展，可以修改该技术来测量单个细胞内结构的弹性。 因此，这项拟议工作的目的是详细解决以下问题： 1) 通过实验确定三个主要领域的物理参数之间的关系：弹性介质、声学和气泡。 2) 开发理论和数学模型，以深入了解实验结果并根据测量的特性计算样本的未知粘弹性特性。 3）通过绘制具有医学意义的组织（人工晶状体）的弹性空间分布来测试和完善该方法。