AGING EFFECTS ON HUMAN CRYSTALLINE LENS PROPERTIES

调节，即眼睛聚焦在附近物体的过程，发生在 人类通过控制睫状肌的收缩而耦合 晶状体的受控弹性松弛。后者 事件导致透镜形状改变，从而改变其折射率 属性。然而，连接这两个过程的方法是 这是一个有争议的问题，而目前公认的两种理论都不能 充分解释与年龄有关的调节幅度的侵蚀 (老花眼)。这项相互竞争的延续建议的目的是 描述人类晶状体特性的变化作为 通过非侵入性原位技术和体外技术提高晶状体年龄 使用隔离的验尸镜片，并考虑住宿和 在这些研究中的适应性损失。精选黄曲霉毒素的体内研究 作为年龄函数的人类受试者将包括标准临床 诸如厚度测量和角膜曲率测量等技术，以及使用 Scheimpflg法采集收容人员的裂隙灯照片 每个受试者的透镜在整个调节器上的屈光度间隔为2 范围；当分析时，这些照片将提供有关 角膜、晶状体前表面和晶状体后表面的位置， 以及与以下内容相关的所有可辨别曲率的表征 透镜(例如，相邻间断区之间的边界)作为 调节状态的功能。体外研究将使用这两种方法 表征镜片物理弹性的标准和创新方法 和生物化学特性，以及光学特性 镜片是年龄和性别的函数。基于计算机的统计资料包 将用于将这些结果与年龄、性别和 (在适用的情况下)视力，以及基于计算机的修订模型 食宿，包括这些数据，适用于所有人 年龄，将被制定。这些研究旨在填补这一领域的空白 目前对人类晶状体老化过程的了解，并要考虑 直接人类晶状体的变化，这可能与 老花眼的发展。一些可以研究的参数 非侵入性的，以及那些可以侵入性研究的是 与受试者年龄直接相关，因此可用作 老化的过程。

Accommodation, the process by which eyes focus on near objects, occurs in humans through the controlled contraction of the ciliary muscle coupled with controlled elastic relaxation of the crystalline lens. The latter event results in a change in lens shape which alters its refractive properties. The means by which the two processes are coupled, however, is a matter of controversy, and neither of the currently accepted theories can adequately explain the age-related erosion of accommodative amplitude (presbyopia). The purpose of this competing continuation proposal is to characterize changes in human crystalline lens properties as a function of increasing lens age, both in situ with non-invasive techniques and in vitro using isolated post-mortem lenses, and to consider accommodation and accommodative loss in terms of these studies. In vivo studies on selected human subjects as a function of age will include standard clinical techniques such as pachymetry and keratometry, and the use of the Scheimpflug method to collect slit-lamp photographs of the accommodating lens for each subject at 2 diopter intervals over the entire accommodative range; when analyzed, these photos will supply information on relative locations of the cornea, anterior lens surface, and posterior lens surface, as well as characterization of all discernible curvatures associated with the lens (e.g., boundaries between adjacent zones of discontinuity) as functions of accommodative state. In vitro studies will employ both standard and innovative methods to characterize lens elasticity, physical and biodhemical properties, and optical properties of isolated post-mortem lenses as a function of age and sex. Computer-based statistical packages will be used to correlate these results as a function of age, sex, and (where applicable) visual acuity, and a revised computer based model on accommodation, which incorporates these data and which is applicable to all ages, will be formulated. These studies are designed to fill gaps in the current understanding of the human lens aging process, and to consider directly the changes in the human lens which may be associated with the development of presbyopia. Some of the parameters which can be studied non-invasively, as well as those that can be studied invasively, are directly correlated to subject age and can thus be used as "biomarkers" for the aging process.