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Raymond Myers, Suzanne Lakamp; From Accommodation Restoration to the Antioxidant Lens Sink: Theoretical Basis for Lenticular Refractive Surgery. Invest. Ophthalmol. Vis. Sci. 2013;54(15):1817.
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Modifying lenticular structure with a femtosecond laser may restore functions in a younger lens. We propose modifications for lenticular refractive surgery which go beyond accommodation restoration and flexure changes, to restoring a lens antioxidative sink and altering hardness and opacification in specific lens regions.
Physical and chemical properties from the literature suggest a modification potential using a femtosecond laser. Modifiable features include flexure and returning ionic transport through microchannels and grids. Potentially modifiable properties are suggested by the following: 1)Property differences in the pre-presbyopic versus presbyopic eyes; 2)Inert and sequestered properties seen in lens foreign bodies imbedded up to 60 years without cataract development; 3)Association of vitrectomy and cataract development in presbyopic versus non-presbyopic eyes; and 4)Variations of regional oxygen ion concentrations in anterior and posterior chambers with possible effects upon specific diseases including cataracts.
The femtosecond laser applies thousands of pulses to stretch the interstices among lens fibers and modifies covalent bonds. Morphologically, the lens is defined by multiple growth shells where later formed shells are more modifiable for flexural changes. The laser can also produce microchannels and networking where antioxidants and nutrients travel into the depths of the lens. Even a 30 year lens has regions without the essential antioxidant that maintains flexure and clarity.
The hypothesis is modifications occur from inducing functional differences in flexibility or ionic transfer. The flexible non-presbyopic lens is like a sponge secured and stretched while in solution, imbibing nutritional components and ions. A non-flexible lens in a presbyope is like a sponge in a fluid secured but not stretched, and transport occurs through the slow mechanism of osmosis. Lenticular refractive surgery is the modification of refractive parameters including shape and volume. Other lens modifications might stave off presbyopia in 20 or 30 year old eyes past the usual onset in the 40’s. Also, the return of an active lens antioxidative sink treats oxygen ions with glutathione in contrast to increase intralens bonding and opacification sites, and possibly to reduce oxygen in the aqueous fluids.
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