Adding Personalized Wavefront-Compensating Optics to a Contact Lens After Lens Manufacture

University Of Houston, Houston TX

Investigators

Abstract

Project Summary/Abstract: Keratoconus (KC) is a disease of the cornea that induces higher-order optical aberrations (HOAs). Soft contact lenses cannot correct for HOAs, therefore, rigid forms of sphero- cylindrical correction (corneal and scleral gas permeable contact lenses) are commonly prescribed in KC. While rigid corrections quantitatively target sphere and cylinder, they rely on refractive index matching of the tears between the lens and cornea to reduce HOA. However, index matching is an incomplete form of correction, leaving eyes of individuals with KC highly aberrated, and with reduced vision. In today’s clinic, residual HOA renders entire forms of correction (soft lenses) useless for individuals with KC, and reduces the effectiveness of the limited options that are available (rigid lenses). The National Institutes of Health has recognized the need to deliver corrections that reduce HOA, funding work that that targeted residual HOA with a technique known as wavefront-guided (WFG) correction. This method treats HOA in the same quantitative manner as sphero-cylindrical error, targeting the eye-specific level of measured HOA. WFG corrections work, leading to better visual outcomes than index-matching, but while interest exists in WFG soft lenses, WFG corrections are limited clinically to delivery in scleral lenses. Overall, the method has found limited clinical success, with only a small number of scleral lens manufacturers offering HOA correction. This is because current WFG correction methods do not integrate with clinical norms, making them less attractive for clinicians and manufacturers, which keeps them out of reach for patients. This gap in equitable access to low-cost, clinically efficacious corrections for individuals with KC will be bridged by this grant, which will evaluate a process where KC patients work with their clinician to identify any commercially available lens (soft or rigid) that meets their cost, comfort, wear time and care system needs (as a typically-sighted patient would), and applies the HOA-compensating optical correction to that lens after the fact. The premise of this R21 is that any sphero-cylindrical lens prescribed in clinic (scleral or soft) can be modified to become a WFG correction by changing the way HOA correction is applied to the lens. Instead of a lens manufacturer designing the HOA correction into an iterative build of their lens, a 3rd party will modify an already-built lens to include HOA correction. Adding WFG correction to existing commercial sphero-cylindrical (soft or scleral) lenses will usher in a paradigm shift in the delivery of effective, ubiquitous, lower-cost corrections for KC.