With Lasik, my -9 power was removed, and I had cornea thickness of 560 micrometer. Now again, my eyesight has dropped. Can I have the enhancement Lasik or what other options?

You should always be careful about LASIK enhancements. I also think it is a good idea to separate LASIK "enhancements" from "re-treatments." At our facility, the former refers to a secondary laser treatment fairly soon (3-6 months) when the results were not what was the goal. The latter refers to what I suspect is your situation, a laser re-treatment years later for a change in vision.

While not every LASIK surgeon would totally agree, I would not have used LASIK to treat such a high Rx. [There are other options.] The reason is because the risks and possible instability of LASIK tend to go up as the Rx treated gets higher. The more myopia treated, the thinner the cornea left over. You need to establish why this change has occurred in your eyes. Over-thinning a cornea with LASIK or PRK can produce a delayed, slow increase in myopia due to its weakened state ("ectasia"). To treat this "new" myopia with further thinning of the cornea risks accelerating this weakening, in the worst case possible to the point of needing a corneal transplant!

If the cause is not ectasia, it is possible to re-treat with laser, but it would probably be safer to use the surface treatment (PRK) on the healed flap. This is much less likely to cause further problems than further LASIK.

_Written by J. Trevor Woodhams, M.D. - Chief of Surgery, Woodhams Eye Clinic