What is an ICL and how does it work?

What is an ICL and how does it work?The implantable collamer lens (ICL) is an extremely small and thin lens implanted inside the eye. The lens sits behind the iris and in front of the natural crystalline lens.

In 1997 the ‘V4’ ICL model was approved for use in the UK, and quickly became the go-to treatment option for patients who were not candidates for corneal laser treatment. A few years ago an updated model of the lens was introduced, which has further improved the safety of these lenses, particularly with respect to the risk of cataract formation by introducing a tiny hole in the centre of the lens. To date, over 1 million ICLs have been implanted worldwide.

In the UK, the lens is available to treat myopia (near-sightedness) from -0.50 to -20.00 D, hyperopia (far-sightedness) from +0.50 D to +10.00 D and astigmatism up to +6.00 D. The lens comes in 4 different sizes to accommodate for a range of eye sizes.

The most advanced method for ICL sizing is to use the Artemis Insight 100 VHF digital ultrasound scanner and directly measure the area inside the eye behind the iris where the lens will be sitting. It seems intuitively obvious that direct measurement of this space inside the eye will provide better information as to which ICL size to choose, than estimating this size from external measurements. It is important that patients be aware of the different sizing methods and ensure that surgeons are using this most advanced method to minimize the chance of complications or needing an ICL lens exchange surgery.

What is the procedure like?

ICL surgery is typically performed 1 eye at a time with 1 to 3 days between eyes. However, some clinics may operate on both eyes in the same day. The surgery takes approximately 10 minutes. First, a small keyhole incision is made in the cornea. Then, the lens is rolled up and inserted through the small incision. Finally, the lens slowly unfolds inside the eye and then is gently maneuvered into position.

After treatment, you will remain at the clinic for anywhere between 30-60 minutes before receiving a final check which includes eye pressure and lens position review. Eye drops are needed for approximately 1-2 weeks after surgery and you will need to attend a number of follow-up appointments.

Benefits of ICLs?

  • The procedure is reversible. Should your vision change you can have laser treatment to refine your vision. Alternatively, the lens implants can be replaced or removed if need be.
  • Can treat higher and more complex prescriptions.
  • May be able to treat patients with corneal conditions that might not qualify for laser eye surgery such as keratoconus.

Risks of ICLs?

  • As ICL surgery is more invasive than laser eye surgery, it carries greater risks than LASIK or ReLEX SMILE.
  • Minor risks include a short-term increase in eye pressure, and inflammation inside the eye.
  • Expected side effects are similar to laser eye surgery and include mild irritation and halos at night that usually subside over time.
  • Most patients experience only minimal discomfort and are able to go back to work within a few days of the procedure.

If you want to find out if you are suitable for ICL surgery or other treatment options, you can call our friendly team of Patient Care Coordinators on 020 7224 1005, or send us a message.

What is an ICL and how does it work?