Crystalens™ was the first to be approved by the FDA in 2003. This implant mimics the eye’s natural accommodation – the ability to change focus from far to near or vice-versa.
In natural accommodation, the ciliary muscle inside the eye contracts to move the lens forward, bending it somewhat to accomplish close focusing. With presbyopia, beginning around age forty, the lens begins to lose its flexibility and it becomes harder for the ciliary muscle to move and re-shape it.
The Crystalens™ implant is designed to move within the eye, changing focus so that you can see clearly at distance, arm’s length, and near. Its design features flexible hinges that move the implant forward when the ciliary muscle contracts, and backwards as it relaxes.
This implant design really isn’t used anymore as much better designs are available now.