RISKS – LASIK EYE LASER SURGERY

Before deciding to undergo surgery, you should definitely inform yourself about possible complications.

The risk of seeing worse after LASIK surgery than before is very low.

However, as with all medical procedures, a residual risk can never be completely ruled out. The complication rate for LASIK is less than 1%. Possible complications are as follows:

Dry eye
A problem that occurs more frequently with LASIK than with LASEK is dry eye. This can last up to six months (up to a year) and requires frequent use of artificial tears. Almost all patients experience this problem.

Glare
During LASIK, only a portion of the cornea is treated, essentially “reshaped.” The smaller this treated portion is, the higher the refractive error. The refractive error remains in the rest of the cornea. In bright light and during the day, this does not cause problems because the pupil constricts in bright light, allowing light to enter the eye only through the treated portion of the cornea. However, when the pupil dilates, especially in twilight or darkness, increased glare and the perception of halos and double vision can occur. This can lead to problems while driving at night. These changes, however, generally only occur with myopia greater than -5 diopters and hyperopia.

Healing delay

If you have rheumatic diseases, healing may be delayed. During this time, you must have regular check-ups with your ophthalmologist.

Corneal flap displacement
In rare cases, the corneal flap can shift up to a few days after LASIK, for example, due to rubbing the eye, requiring further surgery. Therefore, please do not rub your eyes for the first 48 hours after the procedure!

Residual refractive error after surgery
Depending on the degree of preoperative refractive error, a small number of patients may have a slight residual refractive error after surgery. In such cases, assuming a stable correction, a re-LASIK procedure can be performed to correct this residual refractive error with a laser.

Regression
The risk of worsening vision after surgery is very low. However, refractive error can increase again after treatment if it was not stable at the time of the procedure or due to wound healing processes. In these cases, a follow-up operation for fine-tuning is sometimes necessary, although the residual refractive error can also be corrected with mild glasses or contact lenses.

Flap complications

During the LASIK procedure, a corneal lamella, known as a flap, is prepared using a so-called automated keratome. With the help of an oscillating blade, a corneal flap with a thickness of 0.16 mm is created and lifted upwards like a hinge. In some rare cases (less than 1%), complications may occur during the preparation of this flap:

Thin flap: During cutting, the flap may turn out to be very thin, which can lead to wrinkling of the cornea. In such cases, the eye must be fitted with a contact lens immediately after the procedure and monitored regularly. If this is done carefully, no further problems will arise.

The so-called buttonhole refers to a very thin corneal lamella that has a hole in the central area. In such cases, no laser treatment should be performed; instead, the flap should be repositioned and protected with a contact lens. After around 3 to 4 months, a slightly deeper cut can then be made and the laser procedure carried out.

Free flap: In extremely rare cases, the corneal flap may become completely detached. In such situations, the corneal flap or lenticule should be repositioned, possibly secured with a temporary suture, and/or protected with a contact lens. After approximately 3 to 4 months, a new cut can be prepared and the LASIK treatment can be carried out without difficulty.

Incision-related complications can be almost completely avoided with the new femto-LASIK procedure, in which the microkeratome used for cutting is replaced by a specialised laser.

Epithelial ingrowth

As a further rare complication, ingrowth of the superficial corneal layer, known as the epithelium, may occur under the corneal flap during the first few weeks and may need to be removed by an additional procedure. This side effect only becomes apparent 4 to 6 weeks after LASIK. It is therefore essential that you attend the scheduled follow-up appointments.

Cornea with protrusion

In extremely rare cases, excessive weakening of the cornea with bulging (keratectasia) and significant deterioration of vision may occur. In exceptional cases, a corneal transplant is required to treat this complication.

Infections
In extremely rare cases, an infection with scarring may occur. Effective antibiotic medications are available in the event of an infection.

Other risks associated with LASEK/PRK

Mild, reversible corneal opacities may occur after LASEK/PRK. These can be corrected with medication. In the long term, they usually disappear spontaneously (within 1 to 2 years).

What can you do to see well after surgery?

• Please indicate if you have a rheumatic disease.
• Do not rub your eyes for the first few days after surgery!
• Use the provided eye drops regularly; however, only use the eye drops for as long as your doctor has prescribed; prolonged use of these highly potent medications could damage your eyes.
• Please attend all scheduled follow-up appointments.
• If you experience severe pain or a sudden deterioration in your vision, consult your ophthalmologist immediately.