Types of eye correction surgery explained

By Ali Mearza, consultant ophthalmologist at Chiswick Medical Centre


It has been predicted half of the world’s population could be short-sighted by 2050, with more than two million people in the UK reporting they have eyesight issues. The increase in short-sightedness is in the main being blamed on the amount of time people spend looking at their computer screens and smartphone devices. Glasses and contact lenses are often the solution for poor eyesight, however both have their flaws.

If you are a glasses wearer, then you will be all too familiar with the heavy weight glasses bear on the bridge of your nose or the top of your ears by the end of the day. And it is likely, at some point in your life, you will have left your glasses somewhere.

Contact lenses also have their limitations. It is advised you do not swim or shower when using contact lenses as this encourages bacterial infection. Sleeping with lenses in can cause your eyes to become dry and irritated which increases the risk of infection.

How to improve your eyesight?

One of the most popular alternatives to wearing glasses or contact lenses has been laser eye surgery – a procedure which, I believe, has helped correct the vision of many patients over the last 30 years. However, not many people know that this is just one of many treatments available.


At Chiswick Medical Centre, we have a team of leading ophthalmology consultants who are on-hand to provide you with an initial consultation and investigate any eyesight concerns you may have, before offering the most appropriate treatment option for you. At our centre, our ethos is to provide the very best personalised care using state-of-the-art technology and techniques. We’re skilled in reducing patients’ dependence on glasses with laser or lens-based vision correction techniques.


We highlight a few of these vision correction techniques and eye treatments below:

What is laser eye surgery?

This procedure corrects focusing problems by reshaping the cornea (the transparent ‘window’ at the front of the eye) with a laser. The laser technology in the UK market is becoming so advanced that it can accurately treat a prescription of -5 in less than 10 seconds. Besides being able to correct patients’ vision, laser beam technology can also be used to remove superficial scarring at the top of the cornea and treat certain diseases such as deposits in the cornea and recurrent erosion syndrome – where the top layer of the cornea breaks down and causes irritation.


Of course, the primary reason that ophthalmologists use laser technology is to correct vision. There are two main types of laser eye surgery that we use – LASIK and LASEK – but what are they and what are the differences?

How does Lasik work?

During LASIK treatment, the first laser will create a very thin protective flap on the clear layer of the eye (your cornea). This protective flap is then lifted, and the second laser is used to correct your vision. Both eyes are usually treated on the same day.

What is the difference between Lasik and Lasek?

LASEK is often a better option if you have a thin cornea or medical condition that makes laser eye surgery more challenging to complete. During the surgery, only one laser will be used to correct your vision – rather than the two used in LASIK. For this procedure, an alcohol solution is placed on the surface of your eye via a micro-well. The alcohol solution loosens the thin layer of cells on your eye’s surface. This is then gently moved to the side of your eye, giving your surgeon access to the layer of your cornea which will be treated by the laser.

Who is suitable for laser eye procedures?

  1. Those who require the correction of short-sightedness, also known as myopia
  2. Treatment of long-sightedness and astigmatism up to -6.00
  3. Those older than the age of 18 who have had a stable prescription for more than two years.

What is refractive lens exchange?

Refractive lens exchange is a more involved form of eye surgery and could be an option if laser eye surgery is not suitable. If you have refractive lens exchange, your natural eye lens is removed and replaced with an artificial lens made from silicone or high-grade plastic. The optical properties of the inserted lens can correct almost any refractive defect, including short-sightedness, long-sightedness and astigmatism.


Refractive lens exchange is almost identical to traditional cataract surgery; both operations involve replacing the natural lens with a clear, synthetic implant. The only difference is that cataract surgery is performed to correct blur or light scatter when the vision is not correctable with glasses, whereas refractive lens exchange is used to reduce the need for glasses or contact lenses.

Who is suitable for refractive lens exchange?

This procedure is often offered to patients who are not suitable for laser eye surgery, or for people who need eyesight correction and are already starting to form cataracts. This procedure is likely to be successful if you are:


  1. Aged over 45
  2. Have early signs of cataract formation
  3. Your short or long sight is too marked to make you a good candidate for laser eye surgery.

Duet lens procedure. What is it?

While refractive lens exchange surgery involves the replacement of a natural lens with an artificial lens, the innovative Duet procedure involves the replacement of a natural lens with two artificial lenses. The first artificial lens is a distance lens and is placed within the natural capsule that holds the original lens. This lens is permanent. The second lens is a trifocal lens that restores vision at intermediate and near distances and is positioned in the space just in front of the first lens.

As a living tissue, the health of the eye can deteriorate as we grow older. With the add-on trifocal lens, there is the life-long ability to reverse the multi-focal lens technology should it for any reason become unsuitable. This provides another layer of safety to lens exchange surgery.

The two lenses can be inserted as part of the refractive lens exchange procedure but for those patients who have already had lens surgery with a standard lens, an add-on trifocal lens can be inserted to reduce spectacle dependence.

Who might need a duet lens procedure?

This treatment is often suited to patients who may have already undergone cataract surgery with standard lenses and want to reduce dependence on reading glasses. It could also be suitable for patients who might want to remove the lenses at a later date.

What is phakic IOL surgery?

Phakic lens implant surgery is a type of surgery for severe short-sightedness. It involves implanting an artificial lens into your eye through a small opening in your cornea. The lenses are specifically designed to help focus light more clearly on the retina and are placed into your eye without removing your natural lens; usually preferred for younger people whose natural reading vision is normal.

Who is suitable for phakic IOL surgery?

This procedure can be particularly helpful in improving the vision of people with very severe short-sightedness, or those who have difficulty wearing glasses or contact lenses but are not suitable for laser vision correction.


At Chiswick Medical Centre, our consultants are able to provide clinically appropriate and bespoke advice on all of the vision correction treatments mentioned above. If you would like further detail on any of the procedures discussed, or you would like to book an initial eyesight consultation, get in touch today by calling 020 3993 3684