What is Implantable Collamer Lens (ICL) surgery? Implantable Collamer Lens surgery (ICL), as the name itself suggests, is a procedure, wherein a pair of lens is implanted into the eyes which do not require to be removed like normal contact lenses. These lenses are similar to contact lenses but are inserted within the eyes for long-term vision correction. These lenses, therefore, work with the natural lens of your eyes to improve your vision. During the procedure, the lens is inserted between your iris and your natural lens thru a tiny incision near the cornea.
How is ICL surgery performed? ICl surgery consists of two separate procedures:

• The pre-procedure (iridotomy)
• The main procedure (ICL)

The Pre-procedure (Iridotomy)

• This procedure known as iridotomy is performed at least two weeks prior to the surgery.
• At the outset, the doctor applies anesthesia drops on the eyes to numb the surface of the eyes. An eyelid holder is used to keep your eyelids open and prevent you from blinking during the procedure.
• The surgeon then makes one or two small holes in the edge of the iris (the coloured part of the eye), using laser, to ensure that there will be no intraocular fluid build-up behind the implanted lenses after the surgery, which can lead to glaucoma.
• This procedure takes only a few seconds and prevents pressure build-up after the implant.

The Main ICL Procedure

• On the day of the surgery, the doctor applies anesthetic drops on your eye to numb it.
• Eyelids holders are used to keep your eyelids open and prevent you from blinking.
• The surgeon makes two tiny micro incisions at the base of the cornea.
• Through the incisions, he injects the lens into the eye. The lens is positioned behind the iris and in front of the natural lens.
  (Please Note: The lens is folded in a cartridge, and as soon as it is injected into the eye, it unfolds itself. Since the lens is made of highly biocompatible material it is not perceived as a foreign object by the immune system of the body.)
• A gel-like substance is placed in your eye, to keep your eye safe while the lens is being positioned.
• After the positioning of the lens, the gel is removed from the eye.
• The surgeon then applies eyedrops on your eye to prevent inflammation and infection.
  
  

You will be required to continue with the eye drops for a number of days. 
Once this procedure is complete and you will notice the difference in vision quality immediately. 
The same procedure will be repeated with the other eye after a span of 2-4 weeks.  
There are exceptions though, depending on the patient’s condition sometimes both the eyes are operated on the same day. 
What are the side effects of ICL surgery? The iridotomy procedure performed in the first stage of the ICL surgery may have side effects such as:

• increasing eye pressure for a couple of hours after the procedure,
• glare, or double vision.

More serious side effects of this procedure include:

• inflammation or iritis
• hyphema or bleeding in the anterior chamber of the eye or the space between the cornea and the iris
• injury to the cornea leading to corneal oedema
• retinal burns

These side effects, though rare, can be treated with medication and/or additional surgeries. 
Possible side-effects that may occur post the ICL surgery are:

• infections
• night glare or halos around light sources
• pressure build-up in the eyes which happens not only if the iridotomy is not big enough, but also if the lenses are too big for your eyes. The size of the eye lenses vary for different people. Although the measurement is taken prior to the surgery, it is not an exact science, and therefore at times, bigger lenses block the little openings made during iridotomy. This can be corrected by removing the bigger lenses and inserting smaller ones.  
• overcorrection or under-correction of eyesight. When overcorrection occurs nearsightedness gets altered to farsightedness, and it is vice versa for under-correction. These residual power error conditions can be corrected through enhancement or retreatment surgeries. If however, your cornea is too thin or steep the surgeon will advise you to not go in for additional surgeries and will instead prescribe you glasses or lenses to correct your vision.

A major advantage ICL surgery has over other refractive surgeries is that unlike other refractive surgeries it does not induce dry eyes. 
Please be advised, that ICL does increase the long-term risk of getting cataract earlier in your life.
Are There Any Pre-Surgery and Post-Surgery Guidelines for ICl surgery? You need to avoid wearing contact lenses at least 4 weeks prior to the evaluation of your eyes for ICL surgery. 
The first stage of ICL surgery is the iridotomy procedure. On the day of the procedure:

• you need to avoid applying any makeup, creams or lotions on your face and especially around your eyes
• avoid any form of makeup after the procedure
• if you are a diabetic it would be better for you to discuss with your doctor at length about your insulin intake and the effects of the surgery on your condition
• wear something comfortable on the day of the surgery. Avoid wearing pullovers, turtlenecks, or t-shirts and jewellery

After the main ICL surgery you need to:

• refrain from rubbing your eyes
• wear the protective shield on your eyes for a period of 2 weeks after the surgery, which will prevent you from rubbing your eyes accidentally whilst asleep
• you should avoid direct sunlight and wear sunglasses for at least 1 week after the surgery  
• avoid washing your face and avoid shampooing your hair or using face wash or soap on your face for at least three days
• avoid any rigorous forms of exercises including, weightlifting, swimming, yoga, aerobics, for at least 4 weeks
• avoid sexual activity for at least 1-2 weeks
• avoid hot tubs  
• avoid bending over for at least 2-4 days after the surgery
• avoid using eye makeup for at least 2 weeks after the surgery. And after that, avoid using your old eye makeup on your eyes which may contain bacteria.  
• religiously apply the eye drops given to you after the surgery and also take any medication that is prescribed by the doctor.
• How long will it take to recover from an ICL surgery?It takes a span of 2-4 weeks for each eye to stabilize after an ICL surgery. 
  You will notice your improved vision immediately after the surgery. Over the next couple of days as the eye heals you might find the vision becoming blurry suddenly. It gradually stabilizes, and after about a week you should be able to experience optimum vision. 
  You eye will completely heal over a period of two months.  
  Am I eligible or an ideal candidate for ICL surgery?If you are between 21-45 years of age, are nearsighted (myopic), astigmatism, possess general good health, you have thin corneas (not eligible for LASIK), and do not have a history of glaucoma, iritis, and diabetic retinopathy then you are a good candidate for ICL surgery. 
  You should also have sufficient anterior chamber depth within your eye. The anterior chamber is the area between the iris and the cornea which is filled with fluid. If it is of the proper size it will have sufficient space for the implanted contact lens. 
  Your surgeon will confirm the depth of the chamber during the evaluation to determine your candidacy for ICL surgery. 
  
  
  What is the cost of ICL surgery in India? Depending on the eye power an ICL procedure in which spherical lenses are required will cost around Rs. 55,000 per eye, and the cylindrical power will cost Rs. 80,000 per eye. 
  Are the results of ICL surgery permanent?The results of ICL surgery are considered permanent. However, there exists the possibility of early cataract, which comes as a side effect of this procedure, in which case, additional cataract surgery will be required. This may happen when contact occurs between the natural lens of the eye and the ICL. Due to the contact, the natural lens can become opaque. This condition can be treated by cataract surgery. 
  During the surgery, the natural lens, as well as the Collamer lens, will be removed and new intraocular lens will be inserted.
  If there is no cataract formation, and no other severe side effects, the ICL procedure is considered to have more or less permanent results.