Biomechanical mapping of the optic nerve head and peripapillary sclera using high frequency ultrasonic elastography

使用高频超声弹性成像对视神经乳头和视乳头周围巩膜进行生物力学测绘

• 批准号: 10356053
• 负责人: Qifa Zhou
• 金额: $ 49.16万
• 依托单位: UNIVERSITY OF SOUTHERN CALIFORNIA
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-03-01 至 2024-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10356053
• 关键词: 3-Dimensional; Acoustics; Address; Affect; Age; American; Area; Bilateral; Biomechanics; Blindness; California; Characteristics; Computer software; Cornea; Crystallization; Development; Disease; Early Diagnosis; Elasticity; Elements; Engineering; Evaluation; Eye; Frequencies; Gender; Glaucoma; Goals; Image; Imaging Techniques; Institutes; Measurement; Measures; Mechanics; Monitor; Needles; Optic Disk; Optic Nerve; Oryctolagus cuniculus; Pathogenesis; Patients; Persons; Phase; Physiologic Intraocular Pressure; Principal Investigator; Property; Race; Radiation; Research; Research Personnel; Resolution; Resources; Retina; Risk Factors; Scientist; Sclera; Severities; Shapes; Site; Speed; Statistical Data Interpretation; Stress; System; Techniques; Technology; Testing; Time; Tissues; Transducers; Ultrasonic Transducer; Ultrasonics; Ultrasonography; United States National Institutes of Health; Universities; Variant; aging population; base; blind; clinical practice; disorder risk; elastography; ex vivo imaging; experience; imaging modality; imaging platform; imaging system; in vivo imaging system; mechanical properties; nerve damage; new technology; non-invasive imaging; novel; optic nerve disorder; optical imaging; success; tool; ultrasound

Project Summary Glaucoma is a leading cause of irreversible blindness worldwide, affecting over 2.2 million Americans. With an aging population, it is estimated that by 2020 the number of people suffering from glaucoma will reach 80 million worldwide, with 11 million being bilaterally blind. Although elevated intraocular pressure (IOP) is the primary risk factor for the development of glaucomatous optic nerve damage , the mechanisms by which elevated IOP eventually leads to damage are still unclear. Thus, there is a need to develop novel non-invasive imaging modalities that can measure the fundamental mechanical properties of the posterior sclera, and characterize how they contribute to damage in patients particularly as it relates to age, race, and severity of glaucomatous damage. Such a tool would be an important step forward in ocular research and clinical practice, providing the much-needed ability to evaluate the risk of disease based on person- and eye-specific characteristics. The goal of this study is to develop a novel high-resolution ultrasound-based imaging platform non-invasively measure biomechanical properties of the posterior sclera. To address this goal, we propose two imaging systems utilizing dual frequency configuration. One system consists of a low-frequency (4.5 MHz) ring shape transducer to “push” the tissue, and a needle single element transducer inside to “track” micron-level displacement; Another system is to replace the needle transducer with a high-frequency single crystal linear phased array as receiver for elastography imaging to first acquire real time and high speed elastography imaging of the posterior sclera. 2D/3D acoustic radiation force impulse (ARFI) imaging and shear wave elasticity imaging (SWEI) will be performed on ex-vivo unscaled rabbit sclera that will be preloaded with various IOP levels for evaluation. Our preliminary results have demonstrated the principle of using the dual frequency ultrasonic elastography technique on obtaining the biomechanical properties of the sclera and cornea. Integrating high-resolution ARFI imaging with quantified tissue stiffness measurements via the propagation speed of the associated shear wave can potentially allow us to characterize in detail the association between age and gender on the mechanical properties of the sclera and allow us to explore the relationship with glaucoma

项目概要 青光眼是全球不可逆转失明的主要原因，影响超过 220 万美国人。与一个 人口老龄化，预计到2020年患青光眼的人数将达到8000万 全世界有 1100 万人双眼失明。尽管眼压（IOP）升高是主要风险 青光眼性视神经损伤发生的因素、眼压升高的机制 最终导致损害仍不清楚。因此，需要开发新型非侵入性成像 可以测量后巩膜基本机械特性的模式，并表征 它们如何对患者造成损害，特别是与年龄、种族和青光眼严重程度有关 损害。这样的工具将是眼科研究和临床实践向前迈出的重要一步，提供 急需根据人和眼睛的特定特征评估疾病风险的能力。 本研究的目标是开发一种新型高分辨率非侵入性超声成像平台 测量后巩膜的生物力学特性。为了实现这一目标，我们提出了两种成像系统 利用双频配置。一个系统由低频 (4.5 MHz) 环形传感器组成 “推动”组织，内部的针状单晶传感器“跟踪”微米级位移；其他 系统是用高频单晶线性相控阵代替针式换能器作为接收器 用于弹性成像首先获取后巩膜的实时高速弹性成像。 2D/3D声辐射力脉冲（ARFI）成像和剪切波弹性成像（SWEI）将 在离体未缩放的兔巩膜上进行，该巩膜将预加载各种 IOP 水平以进行评估。我们的 初步结果证明了双频超声弹性成像的原理 获得巩膜和角膜生物力学特性的技术。集成高分辨率 ARFI 通过相关剪切波的传播速度进行量化组织硬度测量成像 可能使我们能够在机械上详细描述年龄和性别之间的关联 巩膜的特性，让我们能够探索与青光眼的关系