Biomechanics of accommodation

点击翻译按钮获取中文摘要

PROJECT ABSTRACT Presbyopia, the progressive age-related loss of near visual function, is associated with a stiffening of the crystalline lens. There are currently several investigational approaches for presbyopia treatment that rely on lens softening or lens replacement with softer materials. Lens softening approaches are expected to have a transformative impact on the field because they are non-invasive and they preserve the anatomical relationship between the lens and other tissues involved in accommodation. They have therefore the potential to restore the natural dynamic accommodative function. However, one of the fundamental roadblocks towards the development of lens softening procedures is that there is currently no method available to directly measure lens stiffness and thus assess the efficacy of lens softening procedures in vivo. The goal of the project is to develop new technology capable of precise spatially-resolved non-destructive, noninvasive and depth-resolved quantitative measurements of the lens mechanical properties in a clinical setting. The technology will combine Brillouin microscopy, Optical Coherence Tomography (OCT), and Optical Coherence Elastography (OCE) - BOE. The instrument will be used to generate the first age-dependent data on lens mechanical properties quantified in vivo as well as quantitatively assess therapeutic procedures aimed to restore accommodation. Our overall hypothesis is that the novel BOE technology can acquire absolute measurements of the lens stiffness gradient with the accuracy and precision required to detect both age-related changes and changes induced by lens softening treatments. The ability to quantify lens softening in vivo will have a major impact on pre-clinical and clinical testing, validation and optimization of lens softening procedures. The project has three specific aims: Aim 1: Develop a combined BOE imaging device for depth-resolved quantitative lens elastography. Aim 2: Validate BOE measurements in animal and human lens ex vivo and animal lens in vivo. Aim 3: Quantify the mechanical properties of the human lens in vivo To accomplish our objective, we have assembled a multidisciplinary team with expertise in optical coherence tomography and elastography (Larin), Brillouin technology (Scarcelli), biomechanical modeling (Aglyamov), clinical ophthalmic instrumentation and crystalline lens physiology (Manns, Parel, Ruggeri, Yoo).