In vivo optical coherence elastography of the cornea: mapping shear and tensile moduli

角膜体内光学相干弹性成像：绘制剪切模量和拉伸模量

• 批准号: 10706960
• 负责人: Seok-Hyun Andy Yun
• 金额: $ 40.12万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-30 至 2025-07-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10706960
• 关键词: Age; Biomechanics; Body part; Caring; Clinic; Clinical; Clinical Data; Collagen Fiber; Cornea; Corneal Stroma; Data; Degenerative Disorder; Dependence; Development; Devices; Diagnosis; Disease; Elasticity; Elements; Error Sources; Eye; Fibrillar Collagen; Fostering; Frequencies; Glaucoma; Goals; Human; Intervention; Keratoconus; Laser In Situ Keratomileusis; Longitudinal Studies; Maps; Measurement; Measures; Mechanics; Mission; Modulus; Monitor; Morphology; Natural regeneration; Ocular Hypertension; Operative Surgical Procedures; Optics; Outcome; Pathologic; Pathological Dilatation; Patients; Physiologic Intraocular Pressure; Play; Procedures; Process; Property; Public Health; Reading; Research; Resolution; Role; Safety; Shapes; Structure; Study models; System; Technology; Testing; Tissues; Ultrasonic Transducer; United States National Institutes of Health; Vision; Visual; Visual Acuity; biomechanical test; clinically relevant; crosslink; diagnostic biomarker; elastography; first-in-human; human study; improved; in vivo; innovation; instrument; interest; mechanical properties; novel; prevent; public health relevance; response; screening; tonometry; tool; viscoelasticity

ABSTRACT The mechanical stability of the cornea supports visual acuity by maintaining corneal curvature, with important implications for refractive surgery and the management of cornea ectasia. However, clinical options for mechanical characterization are limited, particularly when compared to well-established tools for morphological characterization of the cornea. Several commercial and investigational instruments have highlighted the potential value of corneal biomechanical analysis, but these devices have limited accuracy and cannot fully characterize the anisotropic, nonlinear, and spatially varying elastic stiffness of the cornea. The overarching goal of this project is to develop advanced optical coherence elastography (OCE) for comprehensive characterization of corneal biomechanics. The proposed technology harnesses both extensional and flexural elastic waves guided along the cornea to measure in-plane tensile (Young’s) and shear moduli at mm-scale resolution. The first specific aim is to develop an OCE system using non-contact ultrasound transducers optimized to excite both elastic waves efficiently at high frequencies spanning 4- 10 kHz. The second specific aim is to test this OCE system with healthy subjects and investigate the dependence of tensile and shear moduli on age and intraocular pressure in vivo. The third specific aim is to measure tensile and shear moduli in patients diagnosed with keratoconus and to monitor mechanical changes after corneal crosslinking treatment. The fourth specific aim is to analyze changes in the moduli as a result of different corneal refractive surgeries. Various ex vivo measurements and finite-element modeling studies will also be undertaken in order to interpret the clinical data and relate the measured moduli to the microstructure of the cornea. This project will advance our understanding of corneal biomechanics in relation to various natural, pathological, and interventional processes and may lead to a new clinical tool that can improve the diagnosis and treatment of keratoconus, the safety and visual outcome of refractive surgery, and the accuracy of tonometry.

摘要 角膜的机械稳定性通过维持角膜曲率来支持视力， 这对屈光手术和角膜扩张症的治疗具有重要意义。但临床 机械特性的选择是有限的，特别是当与成熟的工具相比时 用于角膜的形态表征。一些商业和研究仪器已经 强调了角膜生物力学分析的潜在价值，但这些设备的准确性有限 并且不能完全表征角膜的各向异性、非线性和空间变化的弹性刚度。 该项目的总体目标是开发先进的光学相干弹性成像（OCE）， 角膜生物力学的综合表征。所提出的技术利用了 沿角膜沿着引导的拉伸和弯曲弹性波，以测量面内拉伸（杨氏）， 剪切模量在毫米级分辨率。第一个具体目标是开发一个使用非接触式 优化的超声换能器，以在跨越4- 100 Hz的高频下有效地激发两种弹性波， 10千赫。第二个具体目标是用健康受试者测试该OCE系统，并研究OCE系统的功能。 拉伸和剪切模量对年龄和体内眼内压的依赖性。第三个具体目标是 测量圆锥角膜患者的拉伸模量和剪切模量， 角膜交联治疗后的变化。第四个具体目标是分析模量的变化， 不同的角膜屈光手术的结果。各种离体测量和有限元 还将进行建模研究，以解释临床数据并将测量的 角膜的微结构的模量。该项目将促进我们对角膜的理解 生物力学与各种自然，病理和介入过程有关，并可能导致 一种新的临床工具，可以提高圆锥角膜的诊断和治疗， 屈光手术的结果和眼压测量的准确性。