You can view the forward movement of the anterior optic with high-frequency ultrasound biomicroscopy."The challenge with the Synchrony involved getting the large lens into the eye, however.

"When we started our studies of the lens," recalls Colombian surgeon and Visiogen consultant Ricardo Alarcon-Jimenez, "we used forceps to implant it, which was really difficult because it's two lenses in one."Early on during the evolution of lens, the company knew it needed a reliable injector, says Dr. "A pre-loaded injector system was eventually developed, and it has made implantation of this complicated lens design surprisingly manageable.

It is the only implant in the world which expands and contracts naturally to give a continuous change in focus without compromising the quality of vision – just like our natural lens when we are young.

In order to achieve that goal, dual-optic accommodating Intraocular Lenses have been designed, whose anterior optic displaces axially to increase ocular power, and focus near objects.

Although dual-optic accommodating IOLs are relatively new, their outcomes are promising, as they provide large amplitudes of accommodation and a greater IOL displacement than single-optic accommodating IOLs.

Como consecuencia, disminuye la capacidad de acomodación, lo que dificulta el enfoque de los objetos cercanos.

Con el fin de restaurar la visión de cerca, se han desarrollado e introducido diferentes dispositivos que producen múltiples focos.

With the aim of restoring near vision, different devices that produce multiple focuses have been developed and introduced.

However, these devices are still unable to restore accommodation.

Sin embargo, dichos dispositivos no son aún capaces de restaurar la acomodación.

A fin de lograr este objetivo, se han diseñado las lentes intraoculares acomodativas de doble óptica, cuya óptica anterior se desplaza axialmente para incrementar la potencia ocular, y enfocar los objetos cercanos.

"The concept behind a dual-optic accommodating system is to be able to place a very high-powered moving optic in every eye and then use a rear minus optic to adjust the net power to whatever is needed for the individual eye," he says.

"What varies is how much minus is in the rear optic, while the anterior optic is greater than 30 D in every eye.""The Synchrony operates according to the Helmholtz mechanism of accommodation," he explains, "with tensing and relaxation of the zonules in response to ciliary muscle contraction and relaxation.

Presbyopia occurs in the aging eye due to changes in the ciliary muscle, zonular fibers, crystalline lens, and an increased lens sclerosis.