Ectasia after LASIK may not be caused by increased central thickness of LASIK flaps, according to a study.
“Measured central flap thickness was not thicker than estimated in most eyes developing ectasia after LASIK. Thus, excessively thick flaps do not appear to be a major contributing factor to the pathogenesis of ectasia after LASIK,” the study authors said.
The retrospective, comparative case series included 50 eyes of 29 patients who developed post-LASIK ectasia. The researchers evaluated central flap thickness using confocal microscopic analysis and compared the results with the anticipated flap thickness based on mean published values for each flap creation device.
In addition, patient demographics, preoperative corneal topographies and residual stromal bed thickness calculations were evaluated.
No significant differences were found between measured and estimated flap thickness or residual stromal bed thickness, according to the study. Also, no significant differences in flap thickness were found for eyes that developed ectasia with normal corneal topographies vs. those with abnormal corneal topographies.