Fig 1: Protein expression in tear film before and after Femto-LASIK. (A) Evaluation of MMP-9 values pre-OP as well as 5 and 90 days after Femto-LASIK revealed no significant differences. (B) The NGF level at all three investigation points was nearly the same. (C) The amount of the pro-inflammatory cytokine IL1-β was not altered following Femto-LASIK. (D) The same levels for the pro-inflammatory chemokine IL-8 were identified in all samples. (E) The CGRP level at 5 days post-OP was significantly downregulated in comparison to pre-OP, but not in comparison to 90 days post-OP. Values are mean ± SEM ± SD; * p < 0.05. Abbreviations: CGRP = calcitonin gene-related peptide; IL = interleukin; MMP-9 = matrix metalloproteinase-9; NGF = nerve growth factor.