New at Vision Clinic : The Femtosecond laser

... LASIK - without cut

This form of LASIK often has the following names: IntraLASE, IntraLASIK, Premium LASIK or First Class LASIK. In this procedure ´the flap`is produced, not by a microkeratome (special scalpel) but by a Femtosekundenlaser. The final correction of the cornea, however is still carried out by the Excimer laser.

Term “LASIK without blade” or “LASIK very Laser” are theoretically correct. They often induce however a mistake in interpretation bus whereas the patient believes that one will not carry out any more cutting in his cornea, the Femtoseconde laser remains a surgery with cutting of the cornea… This one is carried out with a laser instead of a microkeratome.

The Femtosecond laser is an infrared laser with a wave length of 1053 nm. This sends out ultra short light pulses (minute portion of a millionth of a second) with a miniature spot diameter (1/100 mm). The energy of the laser beam is released in the cornea at a predetermined depth and is not, like the excimer laser, discharged on the corneal surface. The photodisruption then divides the tissue forming thousands of tiny bubbles. The Femtosekundenlaser works like a scanner going from one corneal rim to another.

Advantages of the Femtosecond Laser

The advantages of the femtosecond laser are:

• it makes it possible individually to determine the thickness of the corneal cap with a great exactitude and that the incision is more precise than with a traditional microkeratome. This is why it is possible to propose FemtoLASIK to certain patients who presented a too fine cornea for a traditional LASIK.
• it makes it possible to treat corneas of abnormal curve while reducing the risk related to cutting (the too cambered corneas or too punts can increase the risk of “free course” or “short prop hole” at the time of cutting with a traditional microkératome.

Its disadvantages are:

• A longer surgical operation with a time of cutting higher than with a traditional microkeratome
• A slower visual recovery because cutting with the laser induces a certain degree of corneal edema (appearance of liquid in the apaissor of the cornea which disappears into 24 to 48 hours).
• Complications specific to cutting with the laser: Inflammatory syndrome idiopathic, peripheral epithelial invasion more frequent,…

The comparative studies between the techniques of cutting with and without blade did not highlight significant differences in terms of results.

In conclusion, each technique (PRK, LASEK, EpiLASIK, LASIK, FemtoLASIK) has advantages and disadvantages in terms of results, risks, of time of recovery, or cost,…. It will be up to the ophtalmologist to choose with the patient the most adequate technique according to the examination preoperative (importance of the defect to be corrected, keratometric values, thickness of the cornea, time of incapacity, profession, sports activities,….