LASIK surgery is performed to correct someone’s vision by creating a thin flap of corneal tissue using a Microkeratome or femtosecond laser. The flap has a hinge and the corneal flap is flipped over out of the way on its hinge. The excimer laser is used to remove corneal tissue in a manner such that the curvature of the cornea is now properly shaped to correct the person’s refractive error. The flap is turned back over the cornea and put into proper position.
Cornea is the Major Component Responsible for Focusing Light onto the Retina
The cornea is the clear portion in front of the iris (colored portion of the eye) and is the major structure in the eye responsible for focusing light or images onto the retina. The cornea is made up of several layers;
Epithelium (outer layer)
Endothelium (inner layer)
PRK, LASEK, Epi-LASIK
These vision correction procedures are performed by removing the epithelium (surface ablation) in different methods and then the excimer laser is used to change the shape of the cornea.
Trans-Epithelial Surface Correction
Trans-Epithelial surface ablation is a newer form of surgery developed to correct people’s vision and allow them to be glasses free. It is performed in two stages;
The excimer laser is used to remove the corneal epithelium in a precise manner. The ablation can be controlled to a 1 micron level.
Once the epithelium is removed, the excimer laser performs the removal of the proper amount of corneal tissue to change the corneal curvature to correct the person’s vision. A bandage contact lens is placed on the eye to cover the cornea during the healing process. The contact lens is removed after a few days when the epithelium has healed.
Trans-Epithelial Advantages Versus PRK, LASEK. or Epi-LASIK
No alcohol is used to remove the epithelium as in LASEK
No mechanical separation of the epithelium with PRK or Epi-LASIK
Trans-Epithelial laser removal of the epithelium is accurate to micron amounts
Avoids alcohol toxicity
Poor flap quality
No suction devices are applied to the eye
Quicker re-epithelialization compared to the other techniques
Tran-Epithelial Advantages Versus LASIK or Intra-LASIK
Less painful procedure as it is a no touch procedure without any suction devices used
Avoids flap complications associated with LASIK or Intra-LASIK
No late flap complications after the surgery
Greater pain after the surgery for the first few days
Vision recovery is longer versus LASIK or Intra-LASIK
Risk of corneal haze after the procedure compared to LASIK or Intra-LASIK
Summary of Trans-Epithelial Surface Laser Correction
Trans-Epithelial treatment is a newer method for which eye surgery can be done to correct a person’s vision. It is very useful in patients with borderline thin corneas in which flap procedures may not be done, deep set eyes where the suction device may not work well, people who participate in contact sports, risk of ocular trauma in their job, patients who may have fear of a flap being done, and patients with a history of retinal detachment or retina tear.