DESCRIPTION (provided by applicant): Accommodation is a main function of the lens. During dynamic focusing, the shape of the lens is changed. The accommodative ability of the lens decreases throughout life, such that it becomes a noticeable problem by around the age of 40. It is proposed that unique structural features and organization of fiber cells enables them to interface at the sutures. This interfacing results in a change in surface curvature of the lens, as well as an increase in thickness, allowing near focus to occur. Using inter- and intra-lens analysis of post- mortem human lenses, the characterization of these changes has provided an explanation for the differences in accommodative range seen across age. During both aging and accommodation, the lens undergoes characteristic changes that have been measured using wavefront analysis. However, the connection between the subtle changes in appearance of the higher order aberrations and ultrastructure of the lens has not been investigated. Using slit lamp and ray-tracing aberrometry, we plan to create an understanding of normal changes in sutures during accommodation, as well as across age. A normal database of slit lamp suture appearance and aberration patterns will then be used to provide an objective measure for accommodative dysfunction, particularly in younger children, that are not able to report their problems effectively.
PUBLIC HEALTH RELEVANCE: Changes occur in the lens shape and structure with age. We propose to improve methods to detect these changes. We want to provide clinicians with better tools to detect and understand how these changes can affect our ability to focus on a near object throughout life.