Laser Surgery: All-laser LASIK surgery
WHAT IS IT?
This is the most advanced, safe and precise method to carry out an operation to correct myopia, hyperopia and astigmatism with the LASIK technique (the procedure most commonly used in the world).
The difference with conventional LASIK is that the need to use a microkeratome to create a flap by cutting the cornea with a blade is dispensed with. Instead, the flap is created using a specially designed laser known as a femtolaser.
The femtolaser is capable of releasing each pulse’s energy at a predetermined depth in the cornea. Beneath the outer layer of the cornea, thousands of tiny bubbles of carbon dioxide and water vapour are created which evaporate once the superficial outer layer of the cornea has been separated to form a flap. Next, another laser, the excimer laser, is used to sculpt the cornea modifying the curvature and eliminating the visual defect.
The use of the femtolaser, which is controlled by a computer throughout the whole procedure, allows us to adjust the desired parameters in terms of the thickness, diameter, position and width of the flap’s hinge as well as the angle at the edge.
The combined use of two lasers, the femtolaser to make the flap and the excimer laser to remodel the surface of the cornea, makes this procedure the most precise due to the increased accuracy of the laser and the safest because any risks associated with using a bladed microkeratome are eliminated.
Candidates
The all-laser LASIK procedure is recommended for all patients who are suitable candidates for laser surgery to correct myopia, hyperopia or astigmatism. Even many patients who have previously been advised that they are unsuitable candidates for laser surgery due to a variety of problems such as not having the required thickness of cornea can now be operated on because the femtolaser gives us the ability to create a much finer and better quality flap. This allows us to preserve a much greater quantity of corneal tissue and at the same time increases the range of dioptres that can be treated as well as the number of patients that may be considered suitable for refractive surgery of this type.
Why is the operation safer now?
Until now the first stage of the LASIK procedure consisted of making a cut using a mechanical microkeratome with a sterile blade. Although the results achieved with this method have been very good, we can now use a computerised laser which eliminates many of the potential complications that occasionally arise through the use of this type of mechanical instrument.
Why is it more precise?
The creation of the corneal flap using a laser is 100 times more precise than that carried out using a mechanical microkeratome with a conventional surgical blade.
The femtolaser gives us great precision over the dimensions of the corneal flap that is created. Dimensions such as the thickness, diameter, position and width of the hinge and the angle at the edge of the flap are all precisely controlled by the laser.
This high level of accuracy opens up the possibility of creating a corneal flap that is very fine and of a high quality allowing us to preserve a greater proportion of the cornea’s tissue and at the same time increase the range of dioptres that can be treated and the number of patients that are suitable for this type of refractive surgery.
Is the procedure painful?
Because the procedure is carried out using anaesthetic eye drops, LASIK surgery is never painful whether the procedure is carried out using the microkeratome or all-laser LASIK surgery.
However, the treatment carried out with all-laser LASIK is less aggressive than with the conventional microkeratome and, therefore, causes less discomfort. In fact, in tests on patients that had one eye operated on with the microkeratome and the other with the femtolaser, when asked which they would choose, without exception they opted for the second procedure because it caused less discomfort and stress.
