The ageing process of the lens cause different effect at different age:

Between the 40 and 50: the lens loose elasticity and subjects lose the capacity of keeping on focus objects at close distance or reading. This is when we start wearing reading glasses and the condition is called Presbyopia.

Between 50 and 70 when the progressive cloudiness of the lens cause the continue changes of the vision and therefore the continue change of glasses.

Over 70 the lens start to reach that level of cloudiness when even glasses can not overcome it and maintain a good level of vision.

Treatments:  Surgery involves removal of the cloudy lens and replacing with an artificial new lens. 

Artificial lens can be:

Monofocal lens able to give good vision for distance but requiring reading glasses (the preferred option) will or vice versa

Multifocal lens able to give a good range of vision for distance and reading although glasses will be required for small printing or fine details. Not all the eyes are suitable for this option.

Toric lens able to correct refractive issue called astigmatism where the lens has not the same curvature in all his circumference. This would otherwise require glasses.

Secondary Cataract or Posterior Capsular Opacity

Posterior Capsular Opacity (PCO) also know as Secondary Cataract is a visually impairing condition that can manifest at any time after Cataract surgery. When the cataract is removed, the surgeon leaves intact its envelope (capsule) intact to host the new artificial Intra-Ocular Lens (IOL). This envelope is very thin and transparent (as a skin onion) soon after surgery and this may maintain its clarity forever or at any time can gradually become hazier and thicker and therefore impairing the vision. This condition is reversible by breaking the centre of the capsule with a special Laser and so by restoring the clarity of the lens achieve full recovery of the vision. This is a one-off treatment as the capsule does not grow again once lasered.

Treatment: YAG Laser Capsulotomy