Presbyopia – or reading vision problems – is a condition that affects everyone as they get older. It is caused by changes in the crystalline lens, which is located inside the eye. The crystalline lens in the eye is very flexible in youth. This means that it can easily change shape, allowing us to focus over a range of distances, This is a reflex and is done automatically without thought or effort. It is called accommodation. As we age, the lens becomes a stiffer, more rigid structure and it becomes harder for the muscles to get the lens to increase in thickness to become more powerful. As such, focusing up close becomes more problematic.

The decrease in accommodating capability starts very early on in life but presbyopia symptoms are not noticed until patients can no longer read without holding items further away. Presbyopia symptoms include:

• Needing to hold reading material further away in order to be able to read
  
• Eye strain or headaches when reading over long periods of time
  
• Things keep going in and out of focus and you can often have a headache which gets worse as the day goes on

Patients often first notice the deterioration in the winter months when lighting is worse. There is no cure for presbyopia, and no way of slowing its progression. Without intervention it results in blurred near vision.

Presbyopia is caused through changes in the crystalline lens that occur over time. It is a different condition to hyperopia or long sightedness, which it is often confused with. Long sightedness is a refractive error that when corrected will allow clear vision at all distances, whilst presbyopia is a “near vision” only eye condition and any correction given will result in clear near vision but will blur the distance vision.

Age related long sightedness (presbyopia) happens because the lens in your eye thickens as you grow older. Your eye sees by allowing light to pass through the cornea and lens and focus on the retina at the back of the eye. In younger people with normal eyesight, the lens flexes so that the light is focused accurately on the retina no matter what the reading distance is.

However, in people over the age of forty, the lens has less flexibility so cannot always focus accurately when you’re looking at something close up. This deteriorates further the older we get and we find ourselves needing more and more power in our reading glasses to cope.

Traditionally, reading glasses can be prescribed to help patients read clearly, but with them on, distance vision will be blurred. Patients with presbyopia can also be prescribed glasses that have either 2 (bifocal) powers (one for distance and one for near), or multiple powers (multifocal) to allow a more blended vision.

Surgical options are available, however. It is important to discuss these options with your eye surgeon, who will explain which presbyopia treatment option may be best for you. This will depend on a number of factors including the severity of your presbyopia and any other eye conditions you may have.

Clear Lens Extraction or Refractive Lens Exchange, also called permanent lens replacement is an excellent option for treatment of presbyopia. This involves inserting a multifocal intra-ocular lens implant which gives good distance, intermediate and near vision. The surgery is similar to cataract surgery.

Read more about refractive lens exchange surgery at Forest Eye Surgery