Is FLAAK keratopigmentation a safe procedure?

The FLAAK technique uses certified biocompatible pigments and a high-precision femtosecond laser. The pigment is placed within the thickness of the cornea: there is no surgery inside the eye (iris, lens, retina), unlike iris implants. Like any corneal surgery, it carries risks (dryness, glare, inflammation, infection), which Dr Gozlan explains during the consultation; the preoperative assessment is there to rule out eyes that should not be operated on. Dr Gozlan has operated on more than 1,000 patients.

Is the procedure painful?

The procedure is performed under local anesthesia with eye drops, which greatly reduce the eye's sensitivity: during the operation, you mainly feel pressure or contact. Pain or stinging is, however, common in the following hours and days: in a survey of 42 patients treated with the FLAAK technique (BMC Ophthalmology, 2023), 81% reported pain during or after the procedure. These symptoms were temporary in every case and had gone within 48 hours for about half of the patients.

How long does the operation last?

The procedure takes approximately 15 to 20 minutes per eye. It is performed on an outpatient basis — you go home the same day. Full recovery is achieved within 48 to 72 hours.

Can I choose any color?

We offer a palette of natural shades carefully selected to harmonize with each morphology and skin tone. During the initial consultation, Dr Gozlan will guide you toward the colors best suited to your face and aesthetic desires.

What are the eligibility criteria?

A prior ophthalmological consultation is mandatory. Contraindications include certain eye diseases (active glaucoma, severe keratoconus), pregnant or breastfeeding women, and immunocompromised patients. The recommended minimum age is 18 years. The complete preoperative assessment will precisely evaluate your eligibility.

Is the result permanent?

FLAAK keratopigmentation is designed to be permanent: the pigment is placed in the corneal stroma. The shade may change slightly during the first weeks as the pigments integrate into the tissue. In some cases a touch-up may be needed; this is discussed with you during the consultation.

What is the cost of the procedure?

FLAAK keratopigmentation costs €5,500 for both eyes, whatever color you choose, even if the procedure is done in two stages. This price includes the pre-operative consultation, the femtosecond laser procedure and certified pigments. On the day of the procedure, I give you your post-operative prescription, to take to a pharmacy, along with an eye colour change certificate to keep with your passport: when you next renew it, your new eye colour can be shown on it. For reference, the Neoris Eyes clinic list shows, as of October 2026, prices ranging from €5,500 to €10,000 in Europe, depending on the clinic and the country (source: Neoris Eyes clinic list).

→ Price, what's included and booking in detail

→ Compare keratopigmentation prices in Europe

What is the difference between FLAAK keratopigmentation and iris implants?

Iris implants are placed inside the eye; the American Academy of Ophthalmology (AAO) has described serious complications (glaucoma, cataract, corneal damage). With the FLAAK technique, the pigment is placed within the thickness of the cornea: there is no surgery inside the eye. It is corneal surgery, with its own risks, which are explained during the consultation.

Is it possible to return to one's natural color after the procedure?

FLAAK keratopigmentation is designed to be permanent. The pigment integrated into the corneal stroma cannot be removed by a simple procedure. This is why a thorough and considered consultation beforehand is essential before any decision.

Does FLAAK keratopigmentation affect vision?

The pigments are placed in the periphery of the corneal stroma, leaving the central optical zone clear. The technique is designed to change only the apparent color of the eye. Like any corneal surgery, it carries risks (including glare), which are explained during the consultation. Regular eye check-ups remain recommended.

October 26, 2026 — 8 min read

Patient at a slit lamp during a follow-up eye examination

Keratopigmentation complications and touch-ups: what can be corrected

Creator: Dr Yoni Gozlan
Published: 2026-10-26T07:35:10+00:00
Keywords: keratopigmentation complications

Dr Yoni Gozlan

Ophthalmic Surgeon — FLAAK Keratopigmentation Specialist

SFO · SAFIR member · Paris 16th

RPPS 10101201803 · See his background

Upcoming sessions:Nov 19 Dec 23

Before keratopigmentation, many patients ask the same question: "If I don't like the result, can it be fixed?" The honest answer depends on the problem. A colour that is too light or uneven can usually be improved with a touch-up. Other, rarer complications can only be partly corrected, and some consequences cannot be corrected at all. Yoni Gozlan, M.D., ophthalmic surgeon in Paris 16, reviews what the published studies on keratopigmentation show.

Key points

Colour touch-ups are part of the technique: in a reference study, more than one eye in three had a second procedure to adjust the shade.
Light sensitivity, discomfort and dryness in the first days are common and, in published series, usually temporary.
A shade that is too light, uneven or fading can usually be improved by adding pigment. Removing pigment is much harder.
A rare complication, progressive thinning and bulging of the cornea (ectasia), can be stabilised but not reversed.
Your natural eye colour does not come back: the decision should be considered permanent.

Why talk about touch-ups before the procedure

Keratopigmentation places a pigment inside the cornea, in a ring-shaped tunnel created with a femtosecond laser. The amount of pigment, how it spreads and how light passes through the cornea vary from one eye to another. So the first procedure does not always give exactly the shade you want.

The published figures confirm this. In a series of 79 eyes followed for an average of 29 months by Prof. Jorge Alió's team (Cornea, 2021), 35.4% of eyes had a colour touch-up: 8.9% twice and 5.1% three times. After these touch-ups, all patients in the study said they were satisfied with the appearance. A 2023 survey on the FLAAK technique was in fact carried out among patients who had come back for a colour touch-up (BMC Ophthalmology, 2023).

Knowing that touch-ups are common helps you approach the procedure with realistic expectations: a first result that is a little light or uneven does not mean the procedure has failed.

What can usually be corrected

A shade that is too light, uneven or fading

This is the most common reason for a touch-up. The surgeon can add pigment or fill in an area with less coverage. In the 2021 study, a change in colour (7.5%) and colour fading (5%) were among the complications reported, and the authors state that most complications could be managed adequately.

A simple rule follows: it is easier to add pigment than to remove it. That is why the shade is chosen with caution, with the option of intensifying it later.

Symptoms in the first weeks

In the 2021 series, light sensitivity during the first month was the most common complication (30%). In the 2023 survey on the FLAAK technique, 42 patients described their symptoms after the procedure: pain (81%), dry eyes (76%), tingling (71%), red eyes (67%) and glare (56%). All were temporary. Pain, tingling, glare and redness had gone within 48 hours in about half of the patients, and the median duration was 7 days when they lasted longer. In an older series of 234 eyes treated for medical or cosmetic reasons (British Journal of Ophthalmology, 2018), light sensitivity had disappeared at 6 months in 81.8% of the patients affected.

What can only be partly corrected

Corneal ectasia

Ectasia is a progressive change in the shape of the cornea that can affect vision. It is rare, but it has been described after cosmetic keratopigmentation: a series published in 2024 reports 5 patients (10 eyes) in whom it appeared between 6 months and 4 years after the procedure (Cornea). Among them, one patient had had an MRI scan, another rubbed his eyes intensely because of an allergy, and a third had previously had LASIK for myopia. Three patients were treated with cross-linking, a treatment that aims to stiffen the cornea and stop the progression. It stabilises the cornea but does not restore its original shape.

Removing the pigment

Removing the pigment is not a routine procedure. Two published cases illustrate this. In 2025, a team in Barcelona described a patient whose vision had decreased after keratopigmentation: a corneal flap had to be created with a femtosecond laser and the pigmented tissue removed with an excimer laser, which made the cornea clear again and improved vision (Journal of Refractive Surgery). In 2026, a Korean team reported a removal using another lamellar flap technique (Korean Journal of Ophthalmology). These are isolated cases involving a new corneal surgery: removal should not be seen as a simple way back.

What cannot be corrected

Going back to your original colour: even after removal, the cornea is not the same as before. The French National Academy of Medicine points out that the effects of keratopigmentation are considered permanent (2025).
Slight measurable changes: in a study of 166 eyes (2025), visual acuity, eye pressure and visual field had not changed significantly at 12 months. However, the number of cells in the inner layer of the cornea (endothelium) had decreased slightly, from 2,393 to 2,309 cells/mm² on average, and contrast sensitivity in low light was a little lower, while remaining within normal values.
A ring that does not widen with the pupil: the diameter of the clear central zone is set by the pigment. In the 2021 study, one patient had a visual field limitation (2.5%). The French National Academy of Medicine also notes that this fixed diameter can make it harder to examine the back of the eye, especially its periphery.
How the colour looks: a shade can look more uniform than a natural iris, and the original colour remains visible around the edge of the cornea. A touch-up can adjust the intensity, not change the nature of the result.

What helps limit complications

A complete assessment before the procedure: shape and thickness of the cornea, pupil size in dim light, history of refractive surgery. This assessment helps rule out risk situations such as keratoconus.
Do not rub your eyes: this is one of the recommendations of the authors of the ectasia series.
Mention your keratopigmentation before an MRI scan: some pigments contain metallic compounds.
Choose the shade gradually: starting in a measured way leaves room to intensify.
See an ophthalmologist without delay if pain gets worse, vision drops or the eye becomes very red.

FAQ: complications and touch-ups

Are colour touch-ups common?

Yes. In a series of 79 eyes published in 2021, 35.4% of eyes had a second procedure to adjust the colour, sometimes two or three times. A touch-up usually means adding pigment where the shade is too light or uneven.

Can I go back to my original eye colour?

Not reliably. A few cases of pigment removal have been published, each involving a new laser surgery on the cornea. Keratopigmentation should be considered permanent.

Is light sensitivity permanent?

In published series, it is common at first and usually temporary: in the 2023 survey on the FLAAK technique, all the symptoms reported after the procedure were transient.

Can a shade that is too dark be lightened?

It is harder than darkening a shade, because pigment would have to be removed. This is one of the reasons the colour is chosen with caution during the consultation.

Sources

D'Oria F, Alió JL, Rodriguez AE, Amesty MA, Abu-Mustafa SK. Cosmetic keratopigmentation in sighted eyes: medium- and long-term clinical evaluation. Cornea. 2021;40(3):327-333.
Alafaleq M, van Haselen R, Ferrari F. The safety and effectiveness of a novel annular keratopigmentation technique; a cross-sectional survey of patients. BMC Ophthalmol. 2023;23(1):292.
Alió J, Sanginabadi A, Hojabr AT, Jafari B. Femtosecond laser-assisted keratopigmentation outcomes for pure cosmetic purposes. Am J Ophthalmol Case Rep. 2025;38:102297.
Nouzovská K, Noveyri BB, Abu-Mustafa S, Alió JL. Corneal ectasia following cosmetic keratopigmentation. Cornea. 2025;44(6):779-787.
Alió JL, Al-Shymali O, Amesty MA, Rodriguez AE. Keratopigmentation with micronised mineral pigments: complications and outcomes in a series of 234 eyes. Br J Ophthalmol. 2018;102(6):742-747.
Castanera-Gratacós D, Cerro-Clusella S, Sánchez-Aparicio FI, Gala-Núñez C. Removal of a cosmetic femtosecond laser-assisted keratopigmentation. J Refract Surg. 2025;41(12):e1360-e1363.
Song JY, Shin GY. Surgical reversal of cosmetic femtosecond laser-assisted keratopigmentation using a pupil-sparing stromal lamellar flap: a case report. Korean J Ophthalmol. 2026;40(5):582-584.
French National Academy of Medicine (Académie nationale de médecine), “La kérato-pigmentation des yeux : un essor qui n’est pas sans risques”, press release, 18 June 2025.

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