Does Bowman's layer determine the biomechanical properties of the cornea?

BACKGROUND Bowman's layer is believed to be the stabilizing element of corneal curvature due to its assumed mechanical stiffness. METHODS Uniaxial stress-strain analysis was performed in paired corneal strips to compare the contribution from Bowman's layer. Two central strips were taken from each cornea and Bowman's layer was removed from one of them with the excimer laser. RESULTS Pairwise comparison yielded no statistical difference in elastic or viscoelastic properties according to presence or absence of Bowman's layer. At a strain of 2%, the stress was measured to be (5.06 +/- 2.01) x 10(3) N/m2 with Bowman's layer and (4.72 +/- 1.3) x 10(3) N/m2 without Bowman's layer. Also, the two relaxation times did not differ significantly. CONCLUSIONS These findings imply that Bowman's layer does not contribute significantly to mechanical stability within the cornea.