The whole truth about laser surgery

The correction of myopia, hyper-metropia or astigmatism by laser technique has been done for many years and is actually already very well established. It is still a surgery. By this we mean that, like any other surgical intervention, it has its risks and potential complications. unlikely, but they exist. We say this because it has often come to be seen as an almost miraculous, very rapid technique that does not entail any danger, nor does it need any special care. It is true that, as this is a more superficial technique, it involves fewer risks, but it is not 100% free of them. In order to achieve optimum results, very specific pre- and post-operative guidelines need to be followed. Let us look at all these issues in a little more detail.

What is the laser surgery?

The laser to correct refractive defects (myopia, hypermetropy, and astigmatism) is called Excimer laser. It’s just a concentrated ultraviolet light. A sophisticated system makes it possible to focus this light on a very specific point. A great deal of heat is generated there, allowing very precise and controlled burns to be made in the form of shots. Each burn is performed at the exact point at a high speed, successfully remodeling the cornea’s surface in a few seconds. This polishing succeeds in correcting the refractive defect of the patient, i.e. eliminating its myopia, hypermetropy, or astigmatism.

It should be noted that the Excimer laser has a control device capable of following the movements of the eye (less small) and firing in the exact area with a precision of crecres. Thanks to this system, polishing on the cornea is extremely accurate so that the visual results are truly excellent.

How long does it take to intervene?

It is much longer the preparation time of the instrument and the patient himself than the surgical time itself. Laser treatment lasts only 10–20 seconds. But each eye is operated separately and a number of slices, anesthetic drops, sterilizing the area around the eye, covering the tabs, separating the eyelids, etc. are needed. All this takes time, although it will be no more than 10 minutes per eye. Therefore, in a matter of 15-20 minutes the two-eye speech will be over.

Will I need help after the intervention?

The first hours after the intervention are the most sensitive. Even though some patients are feeling an improvement in their vision at once, it is normal for them to find it difficult to approach at first, to disturb the light or to have a blurry vision.

You will be able to go home on your own foot, but it is imperative that you come with it. Note that the patient will not be able to drive, may feel photophobia (for which we recommend the use of sunglasses) and a sense of sand in the eyes.

The next day the patient will notice a radical change in his vision, which, although it will not be 100% yet, will allow him to make a virtually normal life.

Is there more than one technique?

There are two types of techniques mainly: LASIK and PRK. The choice of one technique or another will depend on the anatomical features of the patient’s eye and the criterion of the ophthalmologist.

What is the difference between LASIK and PRK?

The difference lies in the surface on which laser treatment is applied. The LasIK technique dissects a thin corneal lamella, called a flap, to be able to perform the laser’s features on the resulting surface.

In exchange for the PRK technique, the corneal epithellium is removed, which is a thin layer at the top of the cornea, by a soft scratch, and the laser is applied on it.

Pre and postoperative care

Both a technique and the other require preoperative treatment with very specific drops. In addition, a series of previous biometric tests and calculations must be carried out in order, among other things, to be able to decide which technique is most appropriate, to calculate exactly the graduation to be corrected, etc.

The post-operative care is also different. In LASIK, it is very important that the flap cicatritzi properly. For this, it is essential not to touch or rub one’s eyes for at least the first month after the intervention. Otherwise, the flap could move. This would force repositioning and restarting with the healing process.

In the PRKno technique there is a danger of flap displacement because it does not exist. The main drawback of this technique is that by removing all the epithelium, an open ulcer remains, which it must heal. During this time the patient may experience some pain and fluctuations in vision. The healing process takes about 3 or 4 days. A protective contact lens is placed to reduce the pain as much as possible, and a specific medicinal pattern is prescribed.


Both techniques correct the refractive defect of the patient very precisely. As we have said before, the choice is due to medical criteria, which can be conditioned by the morphological characteristics of the patient’s eye.

What we can say quite clearly is that after treatment is done the patient will not need to re-use his glasses or contact lenses and will get an excellent vision.