Multiscale Modeling of Accommodation and Presbyopia

调节和老花眼的多尺度建模

• 批准号: 7618167
• 负责人: Jane Koretz
• 金额: $ 5.94万
• 依托单位: RENSSELAER POLYTECHNIC INSTITUTE
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-04-01 至 2010-09-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7618167
• 关键词: Address; Aging; Biomechanics; Blindness; Ciliary Muscle; Complement; Cornea; Crystalline Lens; Data; Data Set; Elements; Eye; Fellowship; Goals; Human; Image; Implant; Intraocular lens implant device; Iris; Knowledge; Lead; Lens Fiber; Link; Literature; Measures; Modeling; Molecular; National Eye Institute; Nature; Optics; Presbyopia; Primates; Process; Property; Refractive Indices; Retina; Role; Scientist; Shapes; Simulate; Societies; Specific qualifier value; Surface; Surgical sutures; System; Testing; Thick; Unconscious State; Update; Vision; Vision Disorders; Work; age related; aged; base; design; economic cost; eye formation; fiber cell; fovea centralis; insight; lens; mathematical model; multi-scale modeling; nonhuman primate; response; symposium

DESCRIPTION (provided by applicant): Mathematical modeling can provide insight into a mechanism or process, and can be used to make predications that can be tested experimentally. The long-term goal of the proposed work is to develop a multiscale model that will increase understanding of the human focusing mechanism (accommodation) and the age-related loss of accommodative range (presbyopia). Presbyopia is a multifactorial process, the mechanism of which remains the subject of controversy and disagreement, as does the accommodation mechanism itself. Understanding how presbyopia develops may ultimately lead to strategies for slowing or stopping the process. It is even more important in developing new designs for intraocular lens implants that can take advantage of the eye's unique focusing system to restore a measure of accommodative amplitude. It is the hypothesis of this senior fellowship proposal that most or all of the information necessary to understand the human accommodation mechanism is currently available in the literature, but not in an organized form. This long-term goal has been broken down into three specific aims. Aim 1 is to create an updated and expanded analytic biomechanical model of the crystalline lens and ciliary muscle in human accommodation, using well-defined strain tensor elements as the basis for inverse calculations leading to the incremental change in tractions and forces with an incremental change in refraction. This model will be complemented by a finite element representation using the same data sets and assumptions. Aim 2 is to create an updated and expanded model of image formation by the eye, using paraxial and non-paraxial ray- tracing approaches to test current and theoretical ideas about the shape of the refractive index gradient. This will be used to correlate optical function with biomechanical changes in lens shape, both on the surface and internally. Aim 3 will be concerned with the biomechanical and optical constraints created by crystalline lens structural organization and ultrastructure, and will be the bridge linking the molecular and macromolecular properties of the lens fiber cells with lens function in accommodation. Presbyopia is the most common visual disorder of people aged 40 and over, and, according to the National Eye Institute, "represents a significant economic cost to society". The way that the focusing process changes with aging can provide clues for ways to arrest or slow the loss of visual range. It is also important in the design of intraocular lens implants that can effectively restore focusing ability.

描述（由申请人提供）：数学建模可以提供对机制或过程的深入了解，并可用于进行可通过实验进行测试的预测。拟议工作的长期目标是开发一个多尺度模型，以增加对人类聚焦机制（调节）和与年龄相关的屈光范围损失（老花眼）的理解。老花眼是一个多因素的过程，其机制仍然是有争议和分歧的主题，调节机制本身也是如此。了解老花眼是如何发展的，最终可能会导致减缓或停止这一过程的策略。这在开发眼内透镜植入物的新设计中甚至更重要，所述眼内透镜植入物可以利用眼睛的独特聚焦系统来恢复测量的屈光幅度。这是这个高级奖学金提案的假设，大部分或所有必要的信息，以了解人类的住宿机制，目前可在文献中，但不是在一个有组织的形式。这一长期目标分为三个具体目标。目的1是创建一个更新和扩展的分析生物力学模型的晶体透镜和睫状肌在人类的住宿，使用定义良好的应变张量元素作为基础的逆计算导致的增量变化的牵引力和力的增量变化折射。该模型将通过使用相同数据集和假设的有限元表示来补充。目的2是创建一个更新和扩展的眼睛成像模型，使用近轴和非近轴光线跟踪方法来测试当前和理论上的想法的形状的折射率梯度。这将用于将光学功能与透镜形状的生物力学变化（表面和内部）相关联。目的3是研究晶体透镜结构组织和超微结构对生物力学和光学特性的制约，并将成为连接透镜纤维细胞的分子和大分子特性与透镜调节功能的桥梁。老花眼是40岁及以上人群中最常见的视觉障碍，根据国家眼科研究所的说法，老花眼“对社会造成了重大的经济损失”。聚焦过程随年龄变化的方式可以为阻止或减缓视觉范围的丧失提供线索。在设计能够有效恢复聚焦能力的眼内透镜植入物时也很重要。