Reproducibility of the thickness of Lasik corneal flaps made by IntraLase FS 60 laser femtosecond (IntraLase, AMO USA) measured by OCT spectral domain (Heidelberg, Germany)

Purpose The objective of this study was to appreciate the reproducibility of the thickness of Lasik corneal flaps made by the IntraLase FS60 laser femtosecond (IntraLase, AMO USA). Methods It was a retrospective, randomized, double-blind study.Twenty eight eyes were included in the study. Every flap was program to measure 120 µm. The flaps were measured by Spectral Domain OCT (Heidelberg), one month after surgery in five points on a horizontal line through the center of the pupil (center, 1mm and 2 mm from the center pupil in nasal and temporal) The scheduled and the obtained thicknesses were compared in each point. Results Double reading by two different doctors showed no significant difference in the thickness flap measurements (p<0.3). Average obtained thickness was 6, 84 µm greater than desired thickness (standard deviation of 7, 27 µm), (p<0, 01). The average thickness flap was significantly greater: nasal 2mm: 128µm +/-7µm, nasal 1mm: 124.4µm+/-6µm, central: 127.7µm+/-8µm, temporal 1mm: 125.9µm +/-7µm, temporal 2mm: 128.2µm +/-8 µm (p<0.01). Conclusion We have shown in this study that the cutting of a corneal stromal flap during a LASIK procedure is significant thicker with the IntraLase FS60, but the standard deviation is low.