الفهرس 
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Abstract
Presbyopia (Greek word ”presbys” meaning ”old person”) describes the condition where the eye exhibits a progressively diminished ability to focus on near objects with age. Presbyopia’s exact mechanisms are not known with certainty; however, the research evidence supports a loss of elasticity of the crystalline lens, although changes in the lens’s curvature from continual growth and loss of power of the ciliary muscles have also been postulated as its cause.
The Presbyopia in patients with primary senile cataract could be managed with cataract extraction then presbyopia correction with glasses, contact lens or refractive surgery, or simultaneous correction of cataract and presbyopia by implantation of presbyopia correcting IOL.
Glasses: simple reading glasses, bifocal,trifocl and varifocal
Contact lenses: Monovision or Bifocaland Trifocal which can be either simultaneous or translating.
Refractive surgery: PresbyLASIK, Conductive Keratoplasty, Intracorneal inlays and onlay.
Presbyopia IOLs can be either Multifocal or Accommodating
There are many presbyopic IOLS but there are only few that got the FDA approval and they are the refractive IOL (ReZoom IOL), the diffractive IOL (ReSTOR IOL) as well as the accommodating IOL (Crystalens IOL).
Some recent advances have been introduced aiming to improve the quality of vision of the presbyopic patients like:
Power Vision IOL which depends on hydraulically induced shape change that is controlled by the ciliary muscle depending on Accomodation change.
LiquiLens IOL Which is gravity dependent, the optics consists of a fluid chamber. Looking on downward gaze the high refractive index fluid fills the pupillary space creating a more plus power.
Light Adjustable Lens (LAL) it’s a soft and injectable light adjustable Silicone polymer that could be injected into the capsular bag and then irradiated postoperatively by ultraviolet rays to achieve emmetropia ,This could then be followed by further modification in the power of central zone of the optic to create a multifocal Lens.
The injectable IOL in which there is Lens refilling with an injectable polymer after cataract extraction, this material replaces the hard presbyopic lens and thus accommodation could be restored.
Smart IOL is an example of the injectable polymers which has a thermodynamic propriety at temperatures below 20˚ C it is a rigid solid while at temperature above 30˚ C it is a soft gel so it’s a solid rod outside the eye while it transforms into soft gel after filling the capsular bag.
All of those can be great options for many patients, but are not necessarily perfect for everyone. Motivation to achieve spectacle independence is likely to be the deciding factor