Implantable Contact Lenses (ICL)

An Implantable Contact Lens (ICL) is a small implanted lens that is placed inside the eye to correct near or far (short or long) sightedness, with or without astigmatism.

There are now a number of different ways to correct focusing errors with surgery. The choice of which surgery is best depends on many factors. These include:

• age
• level of focusing error
• suitability for laser eye surgery,
• and personal expectations from the surgery

Our surgeon will be able to advise you on which technique will best suit you. In general, those patients currently choosing ICL are those who are not suitable for laser eye surgery, or those who prefer a technique that adds an increased component of ‘reversibility’.

Whilst laser eye surgery works very well for most focusing errors, there are areas where ICL’s are preferred. For nearsightedness, the clarity of vision may start to become reduced after laser surgery above a level of -8. For other patients, even a -6 prescription may be too high because of an unacceptable risk of introducing reduced quality of vision, especially in dim lighting conditions. Levels above +4 for farsightedness may cause similar problems with laser surgery.

Occasionally, we find patients eyes are not suitable because they are structurally weaker, or more prone to eye diseases, meaning laser surgery could permanently make their vision worse.

In these cases ICL surgery may provide a solution as the procedure does not weaken the cornea (front surface of the eye).

Therefore in many cases, particularly those with a large focusing error, a patient’s clarity of vision will be better with an ICL than with laser eye surgery.

Over 125,000 Visian ICL’s have been implanted worldwide. Large scientific studies (as early as October 2001) have demonstrated ICL’s to be safe, effective and provide accuracy of results. Though no surgery is ever 100% safe, ICL implants have been given preliminary approval for use by the FDA in the United States. In the FDA trial, 523 eyes with ICL implantation were followed. 47.3% of eyes gained 20/20 (100% perfect vision) or better and 91.8% 20/40 (legal driving vision) or better.

All eyes implanted with the STAAR™ ICL at Auckland Eye have achieved unaided vision of better than or equal to driving requirements.

67% achieved 20/20 vision, and 71% are seeing better after ICL implantation than they were able to with their glasses preoperatively. No patients have lost any vision, and all have either had their second eye implanted or expressed a desire to do so.

Patients who are particularly suitable for this lens are as follows:

• Inadequate corneal thickness for a laser eye surgery
• Forme Fruste or Clinical Keratoconus
• Previous herpetic eye disease
• Near-Sightedness (Myopia) > -8D
• Far-Sightedness (Hypermetropia) >4D
• Collagen vascular disease or other contraindications for laser

Patients who are unsuitable are:

• Small eyes (inadequate anterior chamber depth (<2.8mm))
• Irregular astigmatism rendering poor BCVA
• Glaucoma
• Cataract

ICL Implants have a very similar recovery period to modern laser eye surgery. It is unusual, but not uncommon for patients to see quite well after 4 hours. Almost all patients are achieving a very satisfactory level of vision within the first 24 hours. Except for swimming, there are no activities that are specifically restricted during the recovery period. Recommendations regarding activities may be made depending on the vision in the other eye.

Compared to laser eye surgery the ICL procedure utilises an expensive implant manufactured to high quality Swiss standards. The ICL is not held in stock and is ordered, couriered and in some instances ‘hand-made’ to fit a specific patient’s eye, thus production costs are significant.

As opposed to laser eye surgery, the ICL implant requires a fully sterile operating theatre environment and the presence of an anaesthetist, which adds considerably to the cost of the procedure.

Infection

This is exceedingly uncommon, but a critical and potential complication with any eye surgery. Because ICL implantation is a short and relatively non-invasive operation, the best estimate of risk is very low around 1:3000.

Should an infection occur the eventual visual outcome would depend on the speed of diagnosis, delay in antibiotic administration, type of bacteria or organism involved, and host/pathogen response.

Actual outcomes post infection can range from excellent (where the infection has had no effect on the post-operative result) to blindness. Post operative monitoring is therefore critical.

Cataract

In the FDA trial leading to the approval of ICL, only 0.8% of 523 eyes implanted with the ICL developed symptomatic lens opacities (cataract). Removal of these cataracts has not been associated with a significant increase in poor visual outcome.

Recent reports indicate that this complication is much rarer than previously thought. The worst scenario is that a cataract can develop and impair eyesight, which means cataract surgery would be needed to restore eyesight to an acceptable level of vision. Cataract surgery at the present time is the most successful surgical procedure in medicine and is a great backup should this unlikely outcome arise. The reason that this procedure is not undertaken rather than ICL implantation is that in highly nearsighted patients there is increased risk for retinal detachment, and in both near and far sighted candidates there is generally immediate loss of near vision without the addition of reading glasses. This risk is still a very significant factor if cataract surgery becomes necessary as a result of a cataract forming following the ICL procedure.

Residual refractive error (blurriness)

Estimates made to determine the most appropriate ICL though very accurate are not 100% accurate. In a small group of patients, around 3%, the ICL will need to be exchanged for a more suitable power. The costs involved in this further surgery will be borne by STAAR™ and Auckland Eye, however further surgery would only be offered if the risk/benefit ratio was clearly in your best interests. As with all refractive, laser, incisional or intraocular surgery, there is no guarantee that a given level of vision will be achieved. The likelihood of improving unaided vision to a level of your satisfaction is however very high.

Glaucoma

There is a potential long-term risk of glaucoma. The ultimate result in patients with uncontrolled glaucoma is blindness. In this country, this is an extremely unlikely outcome for patients because you will be monitored long term. Any risk of glaucoma will be identified very early and treatment either in the form of drops, laser or incisional surgery will be administered in order to minimise the chance of any visual loss. The incidence of glaucoma with this implant remains exceedingly low. There were no cases reported in the FDA trial.