Here is an excerpt and link to a comment posted by Optometrist Dr. Greg Gemoules who specializes in the treatment of patients damaged by refractive surgery by fitting them with rigid gas permeable contact lenses.
Says Dr. Gemoules:
"Up to 40% of post-RK patients develop progressive hyperopia because of peripheral corneal ectasia due to the cornea being weakened by the incisions. Taking away tissue from the periphery, as is done with PRK or LASIK will not make the cornea any stronger."
DrG: The trend now is to ablate more tissue in the periphery in an attempt to reduce spherical aberration that is typically induced by refractive surgery and is responsible for a portion of the night vision disturbances and loss of visual quality experience by refractive surgery patients. We're just now seeing the long term effects of RK. One would expect that other corneal refractive surgical procedures, all of which compromise corneal strength and integrity, will have similar long term effects.