With the current non-invasive methods of correcting presbyopia (i.e., bifocal or multifocal progressive spectacle lenses) falling out of favor because of the increased desire for spectacle independence, we look toward the new generation of novel concepts of presbyopia treatment. Unfortunately, the majority of these devices were explanted because of the aggressive rates of stromal thinning, melting, haze, inlay decentration, and corneal opacification. These new materials showed promise in that they were transparent and permeable to fluids and nutrients, which provided some assurance the corneal tissue would tolerate them. Two decades after Barraquer experimented with his initial prototype, the concept was revived with the discovery of more biocompatible materials, like hydrogel. However, the abhorrent rates of implant extrusion and corneal necrosis from reactions to the material quickly resulted in these inlays becoming out of favor. These early inlays showed initial signs of success in treating the targeted refractive error. Created for the treatment of high myopia or aphakia, it was designed from polymethylmethacrylate or flint glass. Then, in 1949, we were introduced to Jose Barraquer’s first corneal inlay prototype. An early effort included addition of human donor corneal tissue to a patient’s host cornea to change the refraction, a procedure called additive refractive keratoplasty. The history of surgical presbyopia treatment has oscillated with numerous promising ideas that have fallen short of success. It is a simple method to describe the continuum of progression associated with age related crystalline lens changes that can help patients achieve a better grasp of their presbyopia. Dysfunctional lens syndrome is a term that is gaining more popularity in use for patient education and satisfaction. There have been many other postulated theories of presbyopia to challenge Helmholtz’s theory, yet not one has been universally accepted. This accounts for the diminished power of the lens in cycloplegia. The opposite occurs in cycloplegia: when the ciliary muscle is relaxed, the tension on zonular fibers is increased causing the lens to assume a more flattened shape from the radial zonular tension. This relaxed zonular state allows the lens to obtain a more spherical shape, which leads to an overall increase in refractive power. During accommodation, the ciliary muscle contracts, relaxing the tension on the zonular fibers, thus resulting in a reduced overall lens diameter. The Helmholtz theory of accommodation is the most widely accepted proposed mechanism, which is based on the assumption that the change in the lens shape is due to the change in the ciliary muscle diameter. One of the difficulties associated with presbyopia is that its pathophysiology remains poorly understood. The symptoms of presbyopia begin around the age of 40 years old. With a projected prevalence of 2.1 billion people affected worldwide by 2020, combined with the documented negative health-related impacts, the treatment spectrum has been evolving rapidly. The impact presbyopia has on the quality of life on our aging global population has placed presbyopia treatment in the forefront of significant research. Presbyopia is an age-related progressive decline in the crystalline lens’ ability to accommodate, resulting in the inability to focus on near objects.
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