Synchrony dual optic accommodating lens
It is likely that the ultimate mechanism for presbyopia is a culmination of many factors together resulting in a loss of accommodative amplitude (multifactorial theory).However, it is unclear if these documented changes in the ciliary muscle and the lens sclerosis occur together or if one is a consequence of the other.The elasticity of the capsule is held in check by the normal tension in the zonule so that accommodation consists in the relaxation of the tension in the zonule by the contraction of the ciliary muscle.This permits the capsule to mold the lens into a more strongly curved system (Table 1).Nevertheless, pseudoaccommodation is not a real restoration of accommodation [1, 5].
The aging population, especially in western countries, has created millions of candidates around the world for such interventions.
Pseudoaccommodation may be accomplished by the induction of certain amounts of higher order aberrations and achromatization, among other less important methods , and they should be studied in lenses wherein real accommodation is the target as it is often masqueraded in the outcomes of AIOLs .
Some of these techniques are based on the adequate performance of the ciliary body using part of the physiological accommodative mechanism, but a surgery for the “real” restoration of accommodation has not yet arrived for clinical practice.
Helmholtz (1856) proved that accommodation is accomplished by the change of the power of the crystalline lens associated with the active action of the ciliary body.
It is the difference in refractive power of the eye in the two states of complete relaxation and maximal accommodation.A truly accommodative IOL (AIOL) would be the one capable of undergoing a progressive change in its power in relation with the active contraction of the ciliary body .