The accommodating style IOLs are actually able to flex in response to the ciliary muscle contracting – in a manner similar to how a natural lens would change shape in the younger eye. Very slight motion and flexing of the lens allows the eye to gain more “power” when a patient focuses from distant to near objects.(Figure 5 A & 5 B)
The other mechanism by which an intraocular lens may replace the loss of accommodation is through multifocal optics. The multifocal system has a modified optic (lens portion of the IOL) which is able to modify the light entering the eye and focus some light for near visualization and another portion focuses the energy to allow visualization of distant images. Simply speaking, the multifocal implants, apportions the light to different focal lengths so different distances are in focus; this occurs without effort from the patient and is a totally passive system. Thus, patients do not have to worry about looking through a certain portion of their implant to see at a specific distance.
In summary, advances in cataract surgery and its outcomes have gone hand-in-hand with the evolution of intraocular lenses. The latest quantum leap in IOL technology is the introduction of presbyopic intraocular lenses. Unlike standard monofocal IOLs, these lenses restore the eye’s ability to have a range of clear vision.
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