Whats the difference between lasik and relex surgery?
TRSC International LASIK Center offers a variety of different technologies refractive error correction. Although newer advanced technologies offer increased opportunity for excellent vision, the necessity for using them varies with the individual qualities of each patient’s eyes (such as spectacle prescription, pupil size, corneal thickness, internal higher-order aberrations, and corneal curvature). TRSC’s LASIK Refractive Surgery Specialists will consult with each patient and help guide their decision in order to provide the best possible results.
To help your understanding of the different types of technology available, here is a brief overview of the steps involved in LASIK:
The laser treatment must be made in the middle layer of the cornea in order for the correction to be permanent. A flap is created in the cornea, consisting of about 1/3 the corneal thickness, allowing the surgeon access to the middle layer. This step can be done with either a microkeratome blade or a femtosecond laser.
2. Reshaping of the cornea by an excimer laser
The corneal flap is lifted and folded back, and then an excimer laser is applied to the now-exposed middle layer of the cornea. A cool beam excimer laser is used and causes no damage to the adjacent tissue. At TRSC, we use the Carl Zeiss MEL 80 excimer laser which is capable of performing wavefront correction.
3. Repositioning of the flap
After the excimer laser has reshaped the cornea, the surgeon will place the corneal flap back down on the cornea and smooth it out, making sure there are no wrinkles.
Creating the corneal flap with Bladeless Carl Zeiss FemtoLASIK
Use of the femtosecond laser to create the flap in LASIK has been used by refractive surgeons worldwide for several years. It is the latest technology available in LASIK surgery, and allows LASIK to be an all-laser, bladeless procedure. Carl Zeiss Meditec (Germany) is one of the top manufacturers of high performance optics, including the MEL 80 excimer laser. The MEL 80 is the excimer laser most recently approved by the FDA of the United States, being approved in 2006. The VisuMax femtosecond laser received FDA approval in 2007.
The VisuMax is able to create a very thin corneal flap in 20-30 seconds. The advantage of the VisuMax over the conventional microkeratome is its consistency and precision, using a corneal contact surface that is specifically designed with a curved surface in order to maximize patient comfort and minimize the increase of intraocular pressure during the flap creation process, and result in less damage to the adjacent tissue compared to other top femtosecond lasers. Its 3D ability allows for precise corneal cuts in all three dimensions, meaning everything down to the thickness and angle of the flap edges can be customized for every patient.
Refractive Lenticule Extraction or ReLEx is the newest treatment for correction of refractive errors (myopia and astigmatism). ReLEx uses the femtosecond laser from Carl Zeiss VisuMax in its most advanced form. Similar to the LASIK approach, ReLEx changes the corneal curvature to correct for the refractive error. However, instead of creating a flap, it uses the femtosecond laser to make a small (3-4mm) incision for more accuracy and precision. With a special software program from Carl Zeiss Meditec, Germany, the Visumax calculates the amount and shape of corneal curvature change required to correct the refractive error and makes a customized lenticule in the middle layer of the cornea. This refractive lenticule is extracted (instead of using excimer laser to change curvature of the cornea as in LASIK/FemtoLASIK/PRK) from the small incision.
Advantages of ReLEx: