STTR Phase I: Refractive correction using non-invasive laser-induced refractive index change

这个小企业技术转让（STTR）第一阶段项目能够开发激光诱导折射率变化（LIRIC），用于角膜和水凝胶材料的非侵入性视力矫正。 在美国，有1.5亿成年人使用某种形式的视力矫正，随着人口老龄化，这一数字预计将稳步增长。LIRIC有可能改变激光屈光手术的执行方式以及基于水凝胶的解决方案（例如，接触透镜、眼内透镜）。 对于角膜使用，LIRIC是一种可以改变角膜光学质量而无需切割、消融或去除组织的过程。此外，只有角膜的一薄层得到治疗，这使得患者能够在其一生中随着处方的变化而不断调整其光学器件。这与目前的激光屈光手术技术有很大的不同，后者具有高度侵入性，不允许将来进行调整。在水凝胶材料中，传统的制造技术使用金刚石车削的模具来实现期望的透镜形状。LIRIC可以通过实现即时制造来改变生产模式，降低库存成本。此外，由于LIRIC可以实现任意屈光矫正，因此患者将能够接受定制矫正的处方。 该项目的智力价值在于在低于损伤阈值的情况下操作超快飞秒激光来改变角膜或水凝胶材料的折射率。通过动态改变激光参数（功率和/或扫描速度），可以在角膜或水凝胶中创建任意折射率分布，从而实现近视、远视、散光、老花眼和高阶像差的光学矫正。该提案的研究目标围绕LIRIC工艺的优化。通过研究激光参数和激光传输系统的光学设计的影响，将有可能提高体内LIRIC的有效性和安全性。此外，还将评估配戴LIRIC角膜接触镜的眼睛的视觉性能。通过矫正眼睛的波前像差，LIRIC光学设备有望显著改善患者的视觉质量，超出当前可用技术的能力。

This Small Business Technology Transfer (STTR) Phase I project enables the development of laser-induced refractive index change (LIRIC) for non-invasive vision correction in cornea and hydrogel materials. In the United States, 150 million adults use some form of vision correction, and this number is projected to increase steadily with the aging population. LIRIC has the potential to transform how laser refractive surgery is performed and how hydrogel-based solutions (e.g., contact lenses, intraocular lenses) are produced. For use in the cornea, LIRIC is a process that can alter the optical quality of the cornea without cutting, ablating or removing tissue. Also, only a thin layer of the cornea is treated, which allows a patient to continuously adjust their optics as their prescription changes over their lifetime. This is vastly different from current laser refractive surgery techniques, which are highly invasive and do not allow for future adjustment. In hydrogel materials, traditional manufacturing techniques use diamond-turned molds to achieve desired lens shape. LIRIC can change the production paradigm by enabling just-in-time manufacturing, reducing inventory costs. Additionally, because arbitrary refractive corrections are achievable with LIRIC, patients will be able to receive prescriptions with customized corrections. This capability is unavailable using today's typical manufacturing methods.The intellectual merit of this project resides in operating an ultrafast femtosecond laser below the damage threshold to modify the refractive index of corneal or hydrogel material. By dynamically changing laser parameters (power and/or scan velocity), it is possible to create arbitrary refractive-index profiles in cornea or hydrogel, enabling the optical correction of myopia, hyperopia, astigmatism, presbyopia and higher order aberrations. Research objectives for this proposal are centered around the optimization of the LIRIC process. By investigating the impact of laser parameters and optical design of the laser delivery system, it will be possible to enhance the efficacy and safety of in-vivo LIRIC. In addition, visual performance will also be assessed in eyes wearing LIRIC contact lenses. By correcting the eye's wavefront aberrations, LIRIC optical devices are expected to significantly improve visual quality in patients beyond the capacity of currently available techniques.