Accuracy of LASIK Flap Thickness Obtained Using 2 Types of Moria M2 Single-use Head Microkeratome Measured Postoperatively by Optical Coherence Tomography

Abstract

Background: To investigate the accuracy of corneal flap thickness (FT) and to examine the potential factors that can influence flap thickness obtained using Moria M2 microkeratomes with two kinds of single-use heads. Methods: A retrospective review of the records of 90 patients who had undergone LASIK between Jun 2011 and Jan 2012 at Tri-Service General Hospital was performed. Creation of corneal flap was achieved by automated Moria M2 microkeratome with two different types of single-use head (SU90 and SU130). The right eye was operated before the left eye in each patient, using the same blade. Additionally, the corneal flap thickness was measured in all cases using the Fourier-domain anterior segment optical coherence tomography (AS-OCT) one week later. Results: The mean central thickness of corneal flap was 114.26±4.49μm (Range, 106~127μm) in the SU 90 head and 146.98±3.62μm (Range, 140~157μm) in the SU130 head. The difference between the first and second eye operated was not significant. There were no free flaps, incomplete flaps or flaps with buttonholes in any of our cases. Conclusions: Moria M2 SU 90 and SU 130 produce accurate, reproducible, safe and cost-effective corneal flap. Thin flaps achieved by both single-use heads did not increase the rate of flap-related complications. Furthermore, AS-OCT is a noncontact, rapid, and repeatable tool for measuring corneal flap thickness and making morphological observations.