REFRACTIVE SURGERY

Laser In Situ Keratomileusis (LASIK)
Photorefractive Keratectomy (PRK)

The Laser vision correction helps patients decrease or eliminate dependence on spectacles or contact lenses. The heavy demand for laser vision correction has pushed research to develop new and even more reliable technologies to achieve precise results; and nowadays, there are a variety of safe and effective treatment options for different patients that want to reduce their dependence on spectacles or contact lenses.
 
The decision to have refractive surgery is important and should be made with as much information as possible. It is very important to have realistic expectations: the goal of any refractive surgery procedure is to reduce your dependence on corrective lenses.
 
Before deciding if you are a candidate for refractive surgery, a thorough examination of your eyes needs to take place in our office. This will include a thorough history of past eye conditions, medications, an accurate measurement of your current prescription and some features of your eye anatomy, including a thorough exam of the back of your eye through your dilated pupils.  We will also obtain a corneal topography, which is a measurement of the surface of your eyes. We will put all these pieces together and discuss your goals and expectations. This will determine not only if you are a candidate for Refractive Surgery, but also which of the variety of treatment modalities suits you best.
 


Laser In Situ Keratomileusis (LASIK) is performed by creating a thin flap in the surface of your cornea, which remains attached to the rest of the cornea through a hinge. This flap is folded back to expose the corneal tissue underneath it, and the laser technology is used to “sculpt” the corneal tissue into the desired shape. After the cornea has been reshaped, the flap is placed back in its original position and in a couple of days it will heal in.
The LASIK flap used to be created with an instrument called a Microkeratome, which is a mechanical blade. With the development of new technologies, now we can create the flap using a laser instead of a blade. While the results are the same the laser may have a even better safety profile reducing even further the small risks of the procedure.
LASIK patients recover very quickly, and most of them experience very little, if any, pain or discomfort.  Functional vision also recovers very rapidly, ranging between a couple of days to a week.
Once the flap has been created even though it heals back in place after a couple of days, that portion of the cornea will no longer contribute to the strength of the cornea. This is no problem in patients with thick, strong corneas but, in some patients with normal but thinner corneas, it is necessary to choose a procedure that will not significantly compromise the corneal strength.
 
This is why Photorefractive Keratectomy (PRK) is recommended for some patients with thinner corneas. In this procedure, the epithelium, which is the superficial thin layer covering the cornea, is removed, and the laser reshaping treatment is performed more superficially. After the procedure, a contact lens is placed to ensure regular and smooth healing of the surface layer, which grows back within a couple of days.

 With this treatment, there is no flap creation, and the tensile strength of the cornea is better retained.
 
In terms of the final visual acuity, patients who have PRK achieve outstanding results but tend to have more discomfort in the early postoperative period, and find that the time to achieve the final visual acuity result is much longer than to LASIK.
 
When performing refractive surgery, any final visual outcome can be targeted. For those patients experiencing Presbyopia or loss of near vision may choose to target their dominant eye for a sharp vision at a distance, and to target their non-dominant eye for a sharp vision at near. This way, the brain eventually learns to rely on the distance eye for distance tasks, and on the near eye for near tasks; thus decreasing the need for spectacles to the minimum. This strategy is called Monovision or Blended Vision.
 
If you are interested in refractive surgery, do not hesitate to schedule an appointment with our doctors for a full evaluation and discussion of your options.