Analysis of actual corneal flap thickness and confounding factors between first and second operated eyes.

BACKGROUND AND

OBJECTIVE

To calculate the actual corneal flap thickness during laser in-situ keratomileusis.

PATIENTS AND

METHODS

Fifty-four women and 26 men with refractive error were enrolled in the study. Flaps were created using a MK-2000 microkeratome (Nidek, Gamagori, Japan) with a 130-microm head. The comparisons between both operated eyes of a patient and the correlations between flap thickness and confounding factors were analyzed.

RESULTS

The average flap thicknesses were 134.0 + or - 16.5 and 112.3 + or - 14.4 microm in the first and second operated eye groups, respectively, and the data showed a significant difference between the two groups (P < .001). There were positive correlations between central corneal thickness and flap thickness (first group, P = .017; second group, P = .041).

CONCLUSION

The flap thicknesses of the first operated eye group were thicker than those of the second operated eye group and there was a positive correlation between the flap thickness and central corneal thickness. The coefficient of variation of the flap thickness was greater in the second group than in the first group.