Reproducibility of corneal flap thickness in LASIK

BACKGROUND: The purpose of the microkeratome in laser assisted in situ kera tomileusis (LASIK) is to create a corneal flap of desired thickness, thus e xposing the stroma. The accuracy and repeatability of intended flap thickne ss with the current microkeratome system has not been documented. The purpo se of this study was to determine the precision and consistency of creating a corneal flap thickness of 160 mu m with the Moria LSK-One microkeratome (distributed by Microtech, Inc., Doylestown, PA). PATIENTS AND METHODS: The records of 93 eyes from 67 patients who underwent LASIK were reviewed. The central corneal thickness was measured at baselin e. The microkeratome using a "130" footplate was used to create an intended flap 160 mu m thick, RESULTS: The mean flap thickness for both eyes combined was 153 mu m (S.D. = 28), There was no significant correlation between pre-flap corneal thickn ess or average K and the corneal flap thickness. CONCLUSION: This study provides evidence that the Moria LSK-One microkerato me creates reproducible LASIK flaps consistently near the intended 160 mu m corneal flap thickness. This knowledge enables the surgeon to make a corne al flap with great confidence in the thickness of the excision. In addition , this study provides a clinical, in vivo model for testing corneal flap th ickness.