LFemtosecond laser is a new device manufactured for performing flaps. Its applications are: refractive surgery (Lasik for myopia, hypermetropia and astigmatism), therapeutic treatment (lamellar corneal graft) corneal tunnel for intracorneal rings…
Other clinical indications are under study.
Femtosecond treatment is FDA approved. Clinical studies began in 1980 and commercialization in the beginning of the 90’s.
Femtosecond laser uses very short impulse nearly to 10-15 seconds (Femto second). This very short impulse time reduces thermal effect on electrons creating several thousands of micro bubbles of gaz. Lifting of the flat is then possible with a spatula that the surgeon uses to go through the level of the micro bubbles in the cornea.
Femtosecond laser flap allows the pre-calculation of the diameter of the flap, its thickness and the width of the hinge.
Like micro-keratom it needs applying of a corneal suction ring.
Ideal indications of Femtosecond laser are very flat or very steep corneas and narrow lids.
Doctor Assaf is using Femtosecond LDV from the firm Ziemer.
FEMTOSECOND versus Micro-Keratom:
Clinical results comparing Lasik with Femtosecond and with Micro-Keratom show no significant differences.
Clinical studies comparing Lasik with micro-keratom and Lasik with Femtosecond did not show any superiority of one technique compared to another. From the personal experience of Doctor Assaf, the Femtosecond laser would have its ideal indications in very flat and very thin corneas and narrow lids. One micro-keratom ideal indication is hyperopia because it’s easier to perform decentred flaps in hyperopic patients because visual axis is decentred.
The other disadvantage of Femtosecond is longer time-duration of suction to perform the flap. This can induce more dryness according to some studies. Other disadvantage of Femtosecond Lasik is the cost which is 25 % more than Lasik with micro-keratom because this technique uses disposable expensive material and the laser itself is also very expensive.
(Link: www.ziemergroup.com/ldv)
Different technologies for Refractive Surgery used by Doctor Jean Assaf :