What are Implantable Collamer Lens? An Expert Guide to ICL
What is an ICL?
An ICL, or implantable Collamer lens, is a vision correction technique meant to correct a medium to a high amount of refractive error called myopia -also known as nearsightedness- which may be uncorrectable via other methods. During the procedure, a lens is inserted into the posterior chamber of the eye, which lies behind the iris. The new lens acts like an implantable contact lens, refocusing the light within your eye instead of in front of it, which complements the refraction from your natural lens. An ICL can correct a much higher degree of nearsightedness compared to LASIK and PRK and usually entails a faster recovery time. The Collamer lens itself is an FDA-approved product made up of a biocompatible collagen copolymer, hence the name. Collagen is a naturally occurring protein found in your eye, and the polymer is similar to the substance found in contact lenses.
What is the ICL surgery?
The surgery itself is very similar to cataract surgery. Before the procedure, you will have to come into the office to measure the dimensions of the eye, and to ensure the ICL is safe to implant. If the surgeon decides the ICL is the best course of action, a procedure date will be set. Depending on which version of the ICL is chosen (Visian ICL has several models), you might require a procedure called an iridotomy before inserting the ICL. An iridotomy places two microscopic holes in the iris, which serve as a prophylactic measure against Glaucoma. Newer versions of the ICL have a hole in the center of them, which removes the need for an iridotomy. The iridotomy can be done in the office, and so may be done on the same day as the measurements.
Two days prior to the surgery, you will be started on antibiotic drops. On the day of the surgery, your eyes will be dilated, and you will be given topical and IV sedation. The ICL procedure is painlessly performed under anesthesia, usually in under 30 minutes. The surgeon will create a small opening in the cornea, the clear front layer of the eye, where the lens will be inserted. The packaged ICL is pushed through the opening and then unfurls in the eye. The ICL position is adjusted until perfection, and then the procedure is over. Eye drops and ointments may be placed in the eye to help with healing and to prevent scarring. After the procedure, the surgeon may give you a regimen of eye drop and pills to take to reduce the risk of any healing complications.
You will have a follow-up appointment the day after, and then additional follow-ups in the weeks and months after. Depending on the patient, yearly checkups might be recommended to guarantee the best final vision possible. Most patients can get back to normal activities within a day, although some activities like intense exercise may be limited for a week.
Benefits and Drawback Compared to LASIK?
LASIK is undoubtedly the most popular procedure to correct nearsightedness, but it cannot correct all kinds of myopias. Myopia is measured in diopters, with more negative numbers meaning a more severe degree of nearsightedness. Those with greater than -12 diopters can not be corrected by LASIK. However, the ICL can fully correct up to -15 diopters and can reduce the nearsightedness in those with up to -20. LASIK is also irreversible because it is reshaping the corneal surface, which is not true of ICLs. Although the lens are meant to stay in forever, if the need arises, they can be removed.
The risks and complications are different as well. The ICL procedure does not involve the removal of corneal tissue, which is what leads to many of the complications seen in LASIK, including dry eyes. However, the ICL procedure is eye surgery which can lead to complications not seen in LASIK, including rotation of the lens and an increased risk of Glaucoma. It should be noted that these are exceeding rare.
Who is a Good Candidate? And who isn't?
The specific criteria for candidacy will be measured at the pre-operative eye exam, but overall, the following people should consider an ICL:
- Those with too great a prescription for laser refractive surgeries like LASIK or PRK to correct
- People between the ages of 21 and 45 with a stable prescription for over a year prior to implantation.
- People with generally healthy eyes
- Those with thin corneas who were denied for LASIK
Anyone with the following conditions should be aware and consult a physician before considering an ICL procedure:
- Underlying eye conditions or family history of Glaucoma, Retina detachments, or macular degeneration.
- High Glaucoma risk like in patients with diabetes
- Patients who are pregnant or nursing
- Those with high levels of astigmatism. The ICL can correct moderate astigmatism, up to -2.5 diopters.