Corneal ectasia is one of the most devastating complications after LASIK surgery. Ectasia is considered in patients who developed increasing myopia, with or without increasing astigmatism, loss of uncorrected visual acuity, often loss of best-corrected visual acuity, with keratometric steepening.
Corneal ectasia may develop many years after LASIK surgery and symptoms could go undetected for some time. It is one of the most feared complication following LASIK. It is characterized by progressive thinning with central and inferior steepening of the cornea.
Current theories suggest that the two main causes of post-LASIK ectasia are preexisting corneal pathology (keratoconus or forme fruste keratoconus), mechanical instability produced by the weakening of the residual corneal stromal bed induced by the flap creation, the effect of laser ablation, and probably eye rubbing. Careful pre-operative assessment of the cornea can greatly reduce the risk of ectasia, although it may occur in previously healthy and unsuspected corneas.
In addition, EXTRA caution is urged before proceeding with LASIK enhancements. Because LASIK patients who present for an enhancement with myopic astigmatism may potentially have early ectasia. Careful examination of the topography for asymmetry is always advised. Also, it is important to confirm that the topography and refraction are relatively stable, which means obtaining old records for LASIK procedures performed elsewhere.
In many cases the patient with corneal ectasia is told that a corneal graft or replacement would be required to restore functional vision. However we have found that in the majority of cases excellent quality of vision can be achieved with custom fitted scleral lenses. We have seen many patients with ectasia avoid further unnecessary surgeries and achieve quality of vision with our lenses and custom optics.