Benefits and Risks of ICL surgery

  • Realistic expectations are vital in refractive surgery. Although greatly reduced spectacle dependence can virtually be guaranteed, thin spectacles may still be required where particularly accurate distance vision is desirable, such as night driving. Increasing reliance on reading glasses is the norm for all patients from mid-40s on. Current refractive surgery techniques do not alter this, but the majority of patients are able to enjoy sport, swimming and social life without glasses or contact lenses after ICL implantation, and straightforward enhancement procedures are available for most patients who do not achieve their aims with the initial surgery.
  • Recent clinical trials suggest that 90% of patients implanted for either short- or long-sight end up within just ±1.00D of their target outcome. Many patients in this group would be able to drive comfortably without glasses.
  • Serious loss of sight = less than 1/1000. Because ICL surgery involves placing an artificial lens inside the eye, there is a risk of introducing infection, which may result in serious loss of sight. Based on figures for cataract surgery, which also involves placing an artificial lens inside the eye, the risk of infection is less than 1/1000. An array of precautions is taken to prevent infection, and we aim to ensure that one eye is recovering without any signs of infection before performing surgery on the other. This is the reason why lens implantation operations, unlike eye surface reshaping operations such as LASIK, are not performed on both eyes on the same day. We normally wait a minimum period of 4 days between ICL operations for the right and left eye.
  • Cataract. Contact between the natural lens and the ICL may, in some cases, cause the natural lens to become opaque. If it begins to affect vision, the cloudy lens is called a cataract. Recent studies suggest that the chances of developing a cataract within 3 years of ICL surgery are less than 1%. ICL removal can be combined easily with cataract surgery, in which a new artificial lens, equivalent in focusing power to the ICL, is implanted to take the place of the natural lens. Good distance vision is normally maintained.
  • Revision surgery. One of the key advantages of ICL surgery is that the lens is removable. If any signs of an adverse reaction to ICL implantation are observed during follow-up appointments, the ICL can be removed relatively easily. More commonly, revision surgery involves replacing one ICL with a smaller or larger ICL to improve the fit in the eye. The operation feels much the same as the original implantation, with a similar, rapid recovery. If early revision surgery is required, there is no additional charge.
  • Retinal detachment is a sight-threatening problem, which is more common in people with severe myopia (short sight). Cataract surgery, in which the natural lens is replaced with a new lens, is known to increase slightly the risk of retinal detachment in highly myopic patients. ICL implantation is less invasive, and is not known to increase the risk of retinal detachment. The overriding point is that retinal detachment is a condition that any high myopic patient should be aware of, regardless of whether or not you have refractive surgery. Danger signs are flashing lights within the eye, a sudden new shower of floaters, or the sense that part of your visual field is missing. Careful examination of your eye before ICL surgery will help to identify any predisposition to retinal detachment, and preventative treatment may then be performed.

The risks and benefits of ICL implantation must be set against those for alternative techniques, contact lenses and glasses. Glasses are risk-free, but the ‘bottle bottom’ lenses required to correct high myopia (short sight) and the thick magnifying lenses to correct high hypermetropia (long sight), can be visually unappealing and also have inherent optical limitations, including reduced visual field, edge distortions, and altered image size. Contact lenses produce excellent visual correction for most patients, but may be uncomfortable and inconvenient, and long-term usage can be associated with an increased risk of sight threatening infection. Whilst the risk is low, contact lens wearers should bear it in mind when considering implant-based refractive surgical techniques such as ICL implantation.