Presbyopia is an age-related disorder in which the crystalline lens becomes less flexible, leading to an inability to focus on near objects. External appliances such as bifocal and progressive addition spectacle lenses have routinely been used to overcome the lack of accommodation. More sophisticated technologies such as multifocal contact lenses and intraocular lenses (IOLs) have been successfully employed to treat presbyopia. However, these technologies trade contrast in the final image for multiple planes of focus. This downside is especially apparent in low lighting conditions. To overcome these limitations, accommodating IOLs have been aggressively pursued in recent years, but the performance of existing technologies has been marginal at best. The first generation of accommodating IOLs operates by translating the optic within the eye. The translation provides an effective power change to the total power of the eye, but the magnitude of translation is enormous compared to the force and movement provided by the ciliary muscle. Consequently, these translation-based technologies have demonstrated little or no benefit to the presbyope. The next generation of accommodating IOLs uses a curvature change in one or more of the lens surfaces to produce a change in power. Substantial power changes can be achieved with only small changes in curvature, and as a result this next generation of lenses is likely to lead to better treatment of presbyopia. This proposal examines the development and ex vivo testing of a novel curvature changing accommodating IOL to determine its potential to treat presbyopia. The goal is to demonstrate the feasibility of a lens that can restore accommodation to pseudophakic individuals.
An accommodating intraocular lens based on changing the curvature of one of its optical surfaces is proposed. The new technology overcomes the limitations of existing designs and provides a simpler solution for treating presbyopia. Development of this technology will enable the restoration of accommodation in patients with intraocular implants, allowing them to focus at a continuum of ranges from distant to near objects.
