Management of slipped laser in situ keratomileusis flap following intrastromal corneal ring implantation in post-LASIK ectasia

Two cases of intrastromal corneal ring (Intacs, Addition Technology) implantation to treat post-laser in situ keratomileusis (LASIK) ectasia developed progressive slippage of the flap over the stromal bed, resulting in progressive flattening of the affected meridian. The flattening was thought to have occurred because the poorly healed flap edge could not withstand the change in corneal shape induced by the ring segments. The flap was lifted, debris was removed, and the flap was sutured to the residual stromal bed using interrupted 10-0 nylon sutures passed through two thirds of the cornea. The sutures induced a localized area of scarring that acted as "welding spots" and prevented further flap slippage. Refractive stability after suture removal supports the hypothesis that a sutured flap restores (at least partially) the biomechanical strength of post-LASIK corneas.