Femto-LASIK

Femto-LASIK (synonyms: femtosecond LASIK, intra-LASIK, laser LASIK) is an ophthalmic laser treatment that can be used for both myopia (nearsightedness – defective vision that can result from both an elongation of the bulb (eyeball) and an increased refractive power of the anterior portions of the eye) and hypermetropia (farsightedness – also a defective vision that results from a change in the length of the bulb). However, unlike myopia, in hypermetropia the bulb is shortened, so the relationship between refractive power and bulb length results in decreased vision. Femto-LASIK can also be used for astigmatism (astigmatism of the cornea), as the treatment does not require the use of mechanical devices. This allows a complete abandonment of the surgical incision technique, so that the use of a knife can be replaced by the use of the laser in a high-quality and more than equivalent way. The use of Femto-LASIK has been approved in the United States since 2001 and shortly thereafter was approved in Germany.

Indications (areas of application)

  • No optimization of visual acuity (vision) possible despite wearing a visual aid (e.g., in anisometropia/condition of different refractive ratios of left and right eyes).
  • Intolerance for contact lenses (e.g., triggered by sicca syndrome – symptom complex of mouth (xerostomia) and eye dryness (xerophthalmia)) and visual acuity can not be improved.
  • Need for corrected visual acuity without the use of an additional visual aid (eg, divers or pilots).

Contraindications

The surgical procedure

The abbreviation LASIK stands for laser in situ keratomileusis, which is currently the most commonly used surgical technique in the treatment of refractive anomalies (nearsightedness and farsightedness). The LASIK procedure is composed of the combination of the use of a lamellar corneal incision (incision pattern in which a flap – a thin slice of the cornea – is detached from the cornea and “unfolded”) and excimer laser ablation (excimer lasers produce electromagnetic radiation used for the surgical treatment of refractive anomalies). At this point, the difference between conventional LASIK and Femto-LASIK becomes clear, because in modern Femto-LASIK, the creation of the flap is no longer achieved by a computer-controlled microkeratome (plane specific to the cornea), but by using a femtosecond laser (laser technology based on the principle of emitting light beams whose speed is in the range of a femtosecond (10-15 seconds)). The procedure of femto-LASIK consists of several steps:

  • After cleaning the conjunctiva and superficial eye tissue to reduce the risk of infection, the eye is covered.
  • An eyelid retractor is used to prevent involuntary closure of the patient’s eyelid.
  • After adjusting the settings of the laser to the patient and fixing the bulb (eyeball) by means of a fixation eye ring, a flap is now cut into the upper corneal layer with the femtosecond laser (laser scalpel), as already described above.
  • By viewing the process through a surgical microscope with a monitor, an accurate assessment of the progress of the laser treatment is visible to the doctor.
  • After the completion of the cutting process, the bulb fixation is removed.
  • Now that the incision is complete, the excised portion of the cornea is “flipped” to the side, now allowing the use of an excimer laser.
  • The excimer laser “abrades” the cornea, offering the possibility of correction of refractive error.
  • Subsequently, a reduction (rearrangement) of the corneal folded to the side is performed. Due to the physiological properties of the cornea sucks it without external influence.

Advantages of the femtolaser

  • High peak intensity (high power of the laser).
  • Minimal transfer of heat from the laser to the cornea (cornea).

Possible complications

  • Pain, a watery eye, or the sensation of a burning eye
  • Infection of the cornea (cornea)
  • Scarring of the cornea with possible follow-up surgery (for correction).
  • Detachment of the flap (corneal flap cut in the uppermost corneal layer in conventional LASIK and femto-LASIK).
  • Higher sensitivity to light, so that there may be glare
  • Visual acuity deterioration (in rare cases).

Benefit

Femto-LASIK is one of the most modern procedures of laser treatment of the cornea (cornea). Particularly noteworthy are:

  • Fast surgery, as with all LASIK procedures, and the rapid healing and improvement of vision immediately after the procedure.
  • After 250,000 treatments complication-free incision technique.
  • High precision of the method, which allows precise tissue extraction (tissue removal), which exceeds the standard LASIK procedure.
  • With Femto-LASIK, in addition to the flap thickness, the flap diameter can also be individually adjusted for the patient. Compared to the conventional microkeratome of standard LASIK, the deviations from the intended flap thickness are only 10 µm instead of 30 µm. Furthermore, significantly fewer too thin or too thick corneal flaps are cut.

Especially recommended as a result of the highlighted advantages of the treatment is the use of the femtolaser in patients with fear of using a knife on the eye and those who value a perfect and customized operation.