ICL for High Myopia and Thin Corneas: What to Do When LASIK Is Not an Option

Why some eyes cannot have laser vision correction

One of the most common disappointments in an eye clinic is hearing that you are not a candidate for laser vision correction. Many international patients arrive at our Silom clinic having already been declined somewhere else, often with very little explanation of why. This article, prepared by the YOUNIFY Clinic medical team, explains the reasons behind that answer and what an implantable collamer lens (ICL) can and cannot do.

Laser vision correction works by removing a small amount of corneal tissue to change the curvature of the eye. If the cornea is already thin, or the prescription is high enough that a large amount of tissue would be needed, laser treatment can leave too little cornea behind and raise the risk of long-term structural problems.

A cornea thinner than the accepted threshold. Corneal thickness is a finite resource that does not grow back. The ophthalmologist calculates how much tissue will remain after treatment. If the answer is too little, declining laser surgery protects your eye — it is not a refusal to treat you.

A prescription beyond the range laser can handle safely. The higher the myopia, the more curvature has to be changed and the more tissue is consumed. Past a certain point, outcomes become less predictable and night-vision complaints such as halos and starbursts become more likely.

An irregular corneal shape. Corneal mapping may show distortion or a pattern that suggests a risk of keratoconus, a condition in which the cornea thins and bulges. This is an important warning sign, because laser treatment can accelerate the process.

Significant pre-existing dry eye. Laser treatment temporarily disturbs the nerves of the corneal surface, which can make established dry eye worse during recovery. Our medical team will usually treat the dry eye first and reassess afterwards. If this sounds familiar, read dry eye and digital eye strain as well.

What an ICL is, and how it differs from laser surgery

An ICL (implantable collamer lens) is a very thin lens placed inside the eye through a small incision, behind the iris and in front of your own natural lens. The concept is additive: a lens is added rather than corneal tissue removed, so the thickness and structure of your cornea are left intact.

Three differences matter most. First, no corneal tissue is removed, which makes it a consideration for thin corneas. Second, it covers a range of myopia higher than laser treatment can address. Third, the lens can be removed later if there is a medical indication — laser treatment cannot be undone, because removed tissue does not come back.

The lens material is designed to sit well against the tissues inside the eye, and each lens is ordered individually according to your prescription and the internal dimensions measured during screening. That custom order is the reason an ICL involves a waiting period and costs more than laser correction.

ICL compared with laser vision correction

In short, laser reshapes the cornea permanently, while an ICL adds a lens inside the eye and leaves the cornea alone. Both aim to reduce dependence on glasses, but they suit different eyes and require different follow-up.

These are starting prices benchmarked to the Thai market in 2026 (draft figures, pending ophthalmology sign-off). Your quoted price depends on your prescription and on what the package includes.

If screening shows your eyes are still suitable for laser, see LASIK and FemtoLASIK, and compare the full price picture in how much LASIK costs in Thailand.

Who qualifies for an ICL — and who does not

ICL screening is more detailed than laser screening, because it has to assess your prescription, the internal dimensions of the eye and the health of the inner cell layer of the cornea. None of this can be judged from a spectacle prescription or an old report; it requires measurement.

An ICL is often a reasonable option for people who:

• have myopia beyond the range that laser correction can address safely
• have a cornea thinner than the threshold for a comfortable laser treatment
• live with chronic dry eye that makes laser treatment a poor choice
• are within a suitable age range with a reasonably stable prescription
• have enough internal space in the eye for the lens, as confirmed by measurement
• Special assessment or a different plan is needed if the internal space is too shallow to seat a lens properly
• the inner corneal cell count is below the accepted threshold
• there is raised eye pressure or glaucoma
• a cataract is already affecting vision, in which case another approach may suit better
• there is chronic inflammation inside the eye or retinal disease that needs treating first
• you are pregnant or breastfeeding

The exact numerical thresholds — anterior chamber depth, endothelial cell count, the range of prescriptions accepted — are set by our ophthalmologist from your own measurements rather than published as a general rule.

If ICL turns out to be unsuitable, other routes remain: PRK in selected cases where corneal thickness allows, or continuing safely with glasses and contact lenses designed for high prescriptions, combined with regular retinal checks — which matter a great deal in high myopia.

Planning your trip: screening first, lens ordering, then surgery

The ICL pathway has one step that laser does not: waiting for a custom lens. International patients should plan around it rather than assume a single short visit will cover everything.

• Detailed screening — refraction, dilated retinal examination, measurement of the internal dimensions of the eye, inner corneal cell count, eye pressure and drainage-angle assessment. Contact lenses must be left out beforehand for the period we specify, so build that into your travel dates.
• Consultation with our ophthalmologist — why you are or are not suitable, the lens power to be ordered, your individual risks, and what can realistically be expected.
• Ordering the custom lens — the wait depends on manufacturing and shipping cycles. Our team will give you a clear time frame in writing so you can book flights around it.
• Procedure day — topical anaesthetic drops, you stay awake throughout, the lens is inserted through a small incision, and the time per eye is short. Afterwards you rest, your eye pressure is checked, and someone should accompany you home.
• Close follow-up — a check the next day and then at set intervals to review eye pressure, lens position and clarity, followed by long-term annual review.

Screening and all follow-up appointments take place at our clinic on Silom Road. The implantation itself, being intraocular surgery, is performed by our own medical team in a fully equipped operating theatre at an affiliated hospital.

If you cannot stay in Thailand for the whole sequence, many patients split the trip: screening and lens ordering on one visit, surgery and the first follow-up on the next. Discuss this with our team before you book, and arrange an ophthalmologist at home for the later reviews.

Recovery, aftercare and monitoring back home

Aftercare comes down to three things: take every drop on schedule, do not rub your eyes, and do not skip follow-up. Eye pressure and lens position are the two things being watched, and neither can be judged by how your vision feels.

Before the procedure:

• stop wearing contact lenses for the period the medical team specifies
• complete any preparatory step that has been scheduled for you, exactly as instructed
• no eye make-up on the day, and arrange someone to accompany you
• tell the medical team about every regular medication and any drug allergies
• Afterwards, use anti-inflammatory and antibiotic drops exactly as prescribed for the full course
• do not rub the eye in the early period, and wear the shield at night as instructed
• keep water out of the eye — no swimming or sauna — and avoid heavy lifting for the advised period
• contact the clinic immediately if you have severe pain, increasing redness, rapidly worsening vision, flashes of light or a sudden shower of floaters
• attend every follow-up appointment, including once your vision feels good

Before you fly home, ask us for a written summary of your lens power, your surgery and the follow-up schedule, so that any ophthalmologist can pick up your care. Air travel is usually acceptable once the early check-ups are complete, but the timing should be confirmed by the medical team rather than assumed.

Risks you should understand before you book

Every procedure inside the eye carries risks that you should understand in advance. ICL is a long-established approach with a substantial evidence base, but it is not a risk-free one. Knowing what to watch for is what makes follow-up meaningful.

• Raised eye pressure, particularly in the early period, which is why pressure is measured at each visit
• Suboptimal lens position — if the lens size does not match the internal dimensions of the eye, adjustment or exchange may be considered
• Earlier cataract formation in some patients, which is a long-term monitoring point
• Changes in the inner corneal cell layer, which is why cell counts are done before surgery and repeated afterwards
• Night-vision quality — some people see halos or starbursts around lights, which commonly settles with adaptation
• Infection inside the eye, which is uncommon but requires immediate medical attention if warning signs appear

Our medical team will always explain your individual risk profile from your own measurements before you decide. YOUNIFY uses techniques and equipment certified to international standards.

Cost, and what to check before you compare quotes

In the Thai market in 2026, ICL starts from THB 160,000 for both eyes. The gap between that and laser correction comes from the custom-ordered lens, the more detailed screening, and the longer follow-up commitment. The final figure depends on your prescription and on what the package includes (draft figures, pending ophthalmology sign-off).

When comparing quotes across countries, check the same five lines each time: the screening package, the lens itself, the facility fee for the operating theatre, medication, and how many follow-up visits are included. A headline number that excludes screening and follow-up is not comparable to one that includes them.

If you have been told you cannot have LASIK, that answer deserves a proper explanation and a full set of measurements before you accept it. See ICL — implantable collamer lens to review the service and arrange a screening appointment with our team in Silom, Bangkok.