refractive surgical problem
In this case, a young patient has poor BCVA (0.2) in both eyes that is mainly related to corneal scarring and irregular astigmatism. In addition, the patient has an increasing myopia, which means the corneas are changing with time. He is also contact lens intolerant. Therefore, to improve the BCVA, we must solve the scarring and irregular astigmatism problems.
Several treatment alternatives are available to approach these problems. The residual corneal thickness will be the most important limiting factor in choosing any of them.
- Phototherapeutic keratectomy with viscoelastic material as a masking agent is a simple procedure for removing the damaged cornea, but it does not prevent haze reappearance.
- A single intraoperative application of mitomycin-C 0.02% after superficial keratectomy with a microkeratome seems a better option than a simple PTK, although long-term effects are not well known.
- Automated lamellar keratoplasty, with or without suture, in which a 200 μm thick corneal disc is removed is an excellent option with good results. With this technique, one can use a thicker donor corneal disc if extra tissue is needed for the recipient cornea.
- A deep lamellar graft is another option that is used mainly in cases of a very thin or ectastic cornea. New deep lamellar keratoplasty techniques1 offer good results and allow restoration of normal corneal thickness.
Once the cornea is clear and smooth and the normal corneal thickness restored if necessary, the residual refractive error can be managed in a second step.
© 2001 by Lippincott Williams & Wilkins, Inc.
1. Melles GRJ, Lander F, Rietveld FJR, et al. A new surgical technique for deep stromal, anterior lamellar keratoplasty. Br J Ophthalmol 1999; 83:327-333