Like many people who wear spectacles and contact lenses to improve their eyesight, you would probably have longed for a solution that does away with the inconvenience and risks from using them. You would also have probably heard of LASIK and how as a surgical procedure, it is able to give you the desired freedom from using spectacles and contact lenses.
LASIK or more accurately Laser Vision Correction (LVC), corrects refractive errors such as myopia (short-sightedness), hyperopia (long-sightedness) and astigmatism. As its name suggests, it utilises a laser to correct the refractive errors. There are 3 main types of LVC: ReLEx SMILE, LASIK and Advanced Surface Ablation (PRK, Epi-LASIK, LASEK, TransPRK) – refer to the table in the next section for the differences.
As long as LVC has been around however (since the 1990s), there is another procedure which is able to give you the independence from spectacles and contact lenses but with greater flexibility and benefits. The Implantable Collamer Lens (also colloquially known as Implantable Contact Lens) (ICL) surgery, involves placing a permanent contact lens in your eye to correct myopia, hyperopia and astigmatism. It is considered an additive vision correction procedure, which works in harmony with your eye in a natural fashion. The procedure is a day surgery, takes only about 20 minutes for each eye and has the following key benefits:
- Minimally invasive with a small incision of 2 to 3mm
- Suitable for thin corneas and better preservation of cornea integrity as unlike LVC, ICL does not remove corneal tissue from the eye
- Provides a better quality of vision than LVC especially at higher levels of prescription
- Lower incidence of dry eye and seeing haloes and starbursts at night compared to LVC at high levels of refraction error
- Reversible: Should the need arise, the ICL can be removed
People who were previously rejected for LVC due to perhaps a higher degree of myopia or astigmatism, dry eye, thin or irregularly shaped corneas, can now look at having an ICL surgery done instead.
Key Aspects and Benefits: ICL Surgery Vs Laser Vision Correction
| Aspects of the Procedure | ICLSurgery | Laser Vision Correction (LVC) | ||
|---|---|---|---|---|
| LASIK | ReLEx SMILE | Advanced Surface Ablation | ||
| Suitable for higher prescriptions of myopia, hyperopia & astigmatism |  |  | ||
| Maintaining corneal integrity – to retain clear and good vision | (as it does not remove corneal tissue) | | ||
| UV protection | | | ||
| Process is reversible | (see next section) | | ||
| Possibility of future procedures | | Limited if it involves the cornea | ||
| Minimallyinvasive | (incision of only 2mm to 3mm) | (flap of only 22mm) | (incision of only 4mm) | (flapless) |
| Suitable forthincorneas | (does not involve the thinning of corneas like in LVC) | Limited (as cornea may be too thin to allow for the creation of a flap) | Limited (as cornea may be too thin to allow for the removal of a lenticule) | (as no flap is needed to be made) |
| Causesdryeye | | (highest level of the 3 LVC) | Sometimes | Sometimes |
| Haloes & starbursts | Sometimes (lower incidence than LVC) | Sometimes | Sometimes | Sometimes (takes the longest time among the 3 LVC procedures to diminish) |
| Resumption to work | 1 week | 3 days | 3 days | 1 week |
*If you currently have dry eye,ICL surgerywhich does not involve the removal of corneal tissue like in LVC,willnot exacerbateyour condition.However, if dry eye is the result of wearing contact lenses, thennot having to wear them after ICL surgery willresult in a decreased incidence of dry eye.
Key Aspects and Benefits: ICL Surgery Vs Laser Vision Correction
| Aspects of the Procedure | ICLSurgery | Laser Vision Correction (LVC) | ||
|---|---|---|---|---|
| LASIK | ReLEx SMILE | Advanced Surface Ablation | ||
| Suitable for higher prescriptions of myopia, hyperopia & astigmatism | No | |||
| Maintaining corneal integrity – to retain clear and good vision | Yes (as it does not remove corneal tissue) | No (as it removes corneal tissue) | ||
| UV protection | Yes | No | ||
| Process is reversible | Yes (see next section) | No (as it removes corneal tissue) | ||
| Possibility of future procedures | Yes | Limited if it involves the cornea | ||
| Minimallyinvasive | Yes (incision of only 2mm to 3mm) | Yes (flap of only 22mm) | Yes (incision of only 4mm) | Yes (flapless) |
| Suitable forthincorneas | Yes (does not involve the thinning of corneas like in LVC) | Limited (as cornea may be too thin to allow for the creation of a flap) | Limited (as cornea may be too thin to allow for the removal of a lenticule) | Yes (as no flap is needed to be made) |
| Causesdryeye | No* | Yes (highest level of the 3 LVC) | Sometimes | Sometimes |
| Haloes & starbursts | Sometimes (lower incidence than LVC) | Sometimes | Sometimes | Sometimes (takes the longest time among the 3 LVC procedures to diminish) |
| Resumption to work | 1 week | 3 days | 3 days | 1 week |
*If you currently have dry eye,ICL surgerywhich does not involve the removal of corneal tissue like in LVC,willnot exacerbateyour condition.However, if dry eye is the result of wearing contact lenses, thennot having to wear them after ICL surgery willresult in a decreased incidence of dry eye.
The Implantable Collamer Lens (ICL)
In ICL surgery, there is no need to remove the natural lens. The ICL is permanently positioned inside the eye between the iris and the natural lens.
ICLs are designed to last over a long period, usually until the time when cataract surgery is required. As indicated in the table in the previous section, the procedure is reversible, so if the need arises, for example, a major change in prescription or to keep pace with technology, the ICLs can be removed.
At Atlas Eye, we use the EVO and EVO+ Visian ICLs that are developed by STAAR Surgical. The product first received the CE mark in 1997 which indicates that it is approved by the European Union and other countries including Singapore that recognise the mark.
The ICL is made of Collamer®, a proprietary material that contains collagen, a naturally occurring protein inside your body, which makes it compatible with your eyes. In addition to being soft, flexible, and comfortable when implanted, the ICL also provides UV protection.
Suitability For ICL Surgery
- Aged 18 and above
- Have myopia (short-sightedness) in the range of -0.50 to -18.00
- Have hyperopia (long-sightedness) in the range of +0.50 to +10.00
- Have astigmatism in the range of -0.50 to -6.00
- Have an anterior chamber depth (space between iris and corneal endothelium) > 2.9 mm and angle > Grade III ¹
- Have a stable prescription for the past 12 months
- Not pregnant or breastfeeding
- Ocular hypertension in either eye
- A previous or pre-existing ocular disease that would preclude post-operative visual acuity of 20/60 or better
- Cataract in the operative eye or non-traumatic cataract in the non-operative eye
- Glaucoma that is primary open angled or narrow angled (glaucoma is a condition where the optic nerve is damaged which may lead to blindness)
- Low/abnormal corneal endothelial cell density, Fuch’s dystrophy or other corneal pathology
- Amblyopia (lazy eye) or are blind in the non-operative eye.
To ascertain your suitability for ICL surgery, you would need to schedule an ICL evaluation with your eye surgeon to undergo a proper evaluation.
Pre-ICL Evaluation
During the evaluation, your eyes will be checked for the level of refractive error (via manifest refraction), corneal thickness and shape, intraocular pressure (fluid pressure within the eye), etc.
You would need to stop using your contact lenses 3 days prior to evaluation if you are using soft contact lenses, and 14 days prior to evaluation if you are using hard contact lenses.
On evaluation day, eyedrops will be administered to dilate the pupils. A temporary effect of this is that you need to remove your glasses for near vision (far vision remains unaffected). Your eyes will also be more sensitive to bright lights so you might want to bring your sunglasses along as the effects of dilation will usually wear off after 4 to 6 hours.
What To Expect When Undergoing ICL Surgery
Before surgery, you would need to stop using your contact lenses in the same manner as before undergoing the evaluation; 3 days prior to surgery for soft contact lenses, and 14 days prior to surgery for hard contact lenses.
On surgery day, you should not drive, so take a taxi or get someone to drive you home. Be prepared to stay in the hospital for about 2 hours, even though the surgery for both eyes itself takes about 30 to 40 minutes.
The first thing that happens when you arrive is for the doctor to administer eyedrops to anaesthetise your eyes and to dilate your pupils – bring your sunglasses to wear after the surgery to minimise sensitivity to bright light.
The surgery begins with a small incision of about 2 to 3mm being made at the base of your cornea. This is relatively painless due to the anaesthetic eyedrops applied earlier.
Next, the surgeon folds the ICL and inserts it through the incision. Adjustments will then be made to ensure that it is positioned correctly. The procedure is repeated for the other eye if required, after which the surgery is completed.
You will be prescribed eyedrops to cleanse your eye and prevent infection from occurring. The incision will self-heal and your vision will start to improve over the next 48 hours. Follow your doctor’s instructions including returning for follow-up visits.
Recovery Post-ICL Surgery
Within a day of the surgery, you should recover about 75% of your vision. You should be fit to return to work the following week.
For the next month or so, you may experience some fluctuation in your vision. This is a normal part of the healing process so there is no need for concern. You can expect your vision to fully stabilise within 3 months.
After surgery, ensure you return for your follow-up visits during the following times: the next day, the week after, 1 month after, and 6 months after.
Guidelines To Ensure A Quick Recovery
In addition to strictly following all the medication instructions given by your eye surgeon, you are to observe the following to prevent any delay in your recovery:
- As with all procedures, you should not drive, operate heavy machinery, or drink alcohol during the first 24 hours.
- Avoid too much reading, computer work, and watching television during the first week after your surgery.
- While sleeping during the first week, use the eye shields that are provided to protect your eyes from being rubbed on accidentally. It is also advisable not to travel during this first week.
- Stay indoors if you can during the first week. If you are unable to do so, avoid going to dusty and smoky areas as particles may enter and irritate the eyes. Better yet, wear protective glasses if you have to leave the house.
- Likewise, during the first week, avoid water entering your eyes when you are having a bath or washing your hair. The same goes for applying makeup and cooking during this time as the chemicals in makeup and cooking fumes may irritate the eyes.
- During the first 1 month after the surgery, you should not swim, do hot yoga, or use the jacuzzi, sauna, and hot tub. Also, avoid contact sports and heavy lifting during this period. Use a headband when you are exercising to prevent sweat from entering your eyes.
Side Effects & Complications Of ICL Surgery
As with any form of surgery, there may be side effects and complications arising from the procedure. However, ICL is considered to be a low-risk surgery, for example, the risk of infection is about 1 in 1,000 people.
When it comes to side effects, they are usually temporary. The more common ones are haloes and starbursts around lights, especially at night. When compared to laser vision correction, these side effects are mild and will usually go away after about 3 months.
Regarding complications arising from surgery, there is a small probability of the following occurring:
- Early onset of cataract – as the ICL is positioned next to the natural lens, the immediate contact may inadvertently precipitate cataracts to form earlier.
- Secondary glaucoma – a condition arising from increased eye pressure which may result in optic nerve damage and vision loss. In the rare event of this occurring, your surgeon will prescribe eyedrops to lower the pressure in the eye. If the eyedrops are still ineffective, the ICL can be removed to prevent further complications.
With the standard of today’s technology and equipment, the likelihood of early onset of cataract, secondary glaucoma and other types of complications, is generally low albeit they are still risk factors you must consider before proceeding with the surgery.
